Long-term follow-up of a hypertension screening program. Of 185 people found to be hypertensive in a shopping centre screening program who went to their physician and had medication prescribed, then were contacted 18 months later, 33 had discontinued the medication at their physician's request. But of 152 who were to continue taking medication 139 (91.4%) had complied. Blood pressure had decreased to less than 160 mm Hg systolic or less than 95 mm Hg diastolic, or both, in 65.1% of the 152; was 160 to 169 mm Hg systolic or 95 to 99 mm Hg diastolic, or both, in 13.8%; was mildly or moderately decreased but still above 169 mm Hg systolic or 99 mmHg diastolic, or both, in 8.6%; and was higher than before the onset of treatment in 3.9%. Adequacy of blood pressure control was not related to age, sex, initial blood pressure values, awareness before the screening of having hypertension, or treatment for hypertension before the screening. Diuretics had been prescribed for 93.5% of the 139 patients, most often as single-pill combinations with other antihypertensive agents.


Adriamycin, 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU-NSC 409462), and cyclophosphamide in refractory adenocarcinoma of the breast and other tumors. Eighty-two patients with metastatic tumor received a therapeutic regimen consisting of BCNU, 100 mg/m2, and cyclophosphamide, 400 mg/m2, both intravenously on day 1, followed by adriamycin, 40 mg/m2, on day 2. Treatment was repeated every 4 weeks. Of 14 evaluable patients with adenocarcinoma of the breast, all resistant to previous chemotherapy and 12 resistant to a five-drug combination chemotherapy program, 12 had objective responses of which seven were good partial responses. Osseous, visceral, and cutaneous metastases responded equally well. Overall, 53% of 68 evaluable patients had objective responses, and 32% had complete or good partial responses. The most encouraging results were in patients with carcinoma of the head and neck, ovarian carcinoma, and multiple myeloma refractory to standard therapy. Significant responses were observed in previously untreated patients with epidermoid carcinoma of the lung, carcinoma of the prostate, and carcinoma of undermined primary. Remissions lasted a median of 5 months. Myelosuppression was moderate in degree and was maximal 2 weeks after treatment. Cumulative thrombocytopenia was apparent but not dose limiting with repeated courses.


The metabolism of cyclophosphamide. Dose dependency and the effect of long-term treatment with cyclophosphamide. Studies on the metabolism of cyclophosphamide-14C were performed in 10 subjects at different single dose levels within the range of 0.02-10 mg/kg body-weight and in five subjects before and following an average 22 days treatment with cyclophosphamide in daily doses of 2 mg/kg. The parameters of cyclophosphamide metabolism--serum half-life of unchanged cyclophosphamide, serum concentration of metabolites, and rates of excretion of cyclophosphamide and metabolites in the urine--were all independent of dose. No change of the metabolism was demonstrated after treatment with cyclophosphamide for 22 days.


Burkitt's lymphoma: a clinical study of 110 patients. One hundred and ten previously untreated patients with Burkitt's lymphoma were studied prospectively over a period ranging from over 1 year to 5 years. Of 103 patients who were treated with cyclophosphamide as a single agent, 79 (77%) achieved complete remission. Vincristine plus methotrexate or cytosine arabinoside induced complete remissions in only two of 24 patients who failed to respond to cyclophosphamide. Fifty-two percent of patients who entered complete remission subsequently relapsed with tumor. Relapse was significantly higher in patients who presented with disseminated disease (Stage III-IV) than in patients with localized disease (Stage I-II). Patients who relapsed early (remission duration  less than 12 weeks) had a significantly worse prognosis than patients who relapsed late (remission duration greater than 12 weeks). Actuarial calculated 2- and 4-year survival for all patients was 44% and 38%, respectively. Factors that adversely affected survival were primary resistance to cyclophosphamide, early tumor relapse, central nervous system disease, and involvement of abdominal organs.


Immunologic assessment of regional lymph node histology in relation to survival in head and neck carcinoma. Histologic material from 84 cases of squamous cell carcinoma of head and neck regions was studied by double blind retrospective analysis. Sections of lymph nodes draining the tumors were examined microscopically to assess the morphologic pattern of response. Patients whose lymph nodes demonstrated active immunologic responses in the form of expanded inner cortices or increased numbers of germinal centers had 5-year survival rates significantly greater than those patients whose regional lymph nodes showed an unstimulated pattern. None of the patients whose lymph nodes showed the depleted pattern survived 5 years. These correlations were independent of the stage or grade of the tumor. Metastases occurred much more frequently in patients having regional nodes showing an unstimulated or depleted pattern than in those whose regional nodes showed evidence of immunologic activity. The data support the concept of a relationship between immunologic activity, progression of neoplasia, and survival. Morphologic assessment of immunologic activity in lymph nodes draining malignant tumors appear to be of significant value in the predicting survival.


Immunologic impairment in patients with non-lymphoid cancer: correlation with the tumoral stage, response to treatment and survival. The cellular immunity has been studied in 121 patients by solid nonlymphoid tumors, and in 50 healthy patients, 11 with benign tumors, with the use of techniques of in vivo dinitrochlorobenzene (DNCB) and in vitro lymphocyte response to phytohemagglutinin to observe the correlation between both tests and the clinical stage of the disease, the response to chemotherapy and surgery, prognosis, and survival. Patients with anergy presented tumoral irresectability, lack of response to chemotherapy, advanced disease, and limited survival. In the patients with good immune response, the disease was limited, responding with greater frequency to therapy and presenting a higher rate of survival. Consequently, the immunologic study of a neoplastic patient can guide us toward a therapeutic behavior and a prognosis.


Chromosomes and causation of human cancer and leukemia. XIV. Origin of a large number of markers in a cancer. A cancerous effusion from a patient with cancer of the breast, with a high modal number of chromosomes (81-83) and with 11-13 abnormal chromosomes (markers) of eight different origins, has been examined in detail karyotypically with C-, G-, and Q-banding techniques. Except for a rare chromosome, all the normal chromosomes were identified and, more importantly, the origin of all markers was ascertained. This study indicates the feasibility of identifying all the chromosomes in cancer cells, even in those with highly polyploid and complicated chromosome constitutions.


Sinus histiocytosis with massive lymphadenopathy: fifteen new cases. Fifteen cases of chronic lymphadenitis with massive hemophagocytic sinus histiocytosis were analyzed. Fourteen patients were whites, 13 were Europeans, and 11 were males; 10 patients were under 10, 4 were over 20, and 2 over 60 years old. The oldest patient died; all other either healed without therapy or are in excellent condition. We studied the cytologic features of lymph node imprints. A 5-year-old girl was examined more thoroughly. High antibody titers to Klebsiella antigens were found repeatedly. The patient also had a constant lymphocytopenia. Phytohemagglutinin-induced blast transformation and lymphotoxin production were within normal limits. No serum Epstein-Barr virus-antibodies could be detected.


Extraskeletal myxoid chondrosarcoma: a clinicopathological study. Extraskeletal myxoid chondrosarcoma is a rare tumor of cartilagenous origin, with only 41 previously reported cases. It has a distinctive histologic pattern and should be distinguished from chondrosarcoma of bone because of its different behavioral pattern. The light microscopic, histo-chemical and electron microscopic features of such a tumor are reported.


Favorable prognosis for survival in children with coincident opso-myoclonus and neuroblastoma. Case reports of 28 neuroblastoma patients who had opso-myoclonus as their presenting feature are reviewed. As compared with the 30%-34% two-year survival rate for the overall population of patients with neuroblastoma, those who exhibited the opso-myoclonus/neuroblastoma combination had a tumor-free two-year survival rate of 89.3%. This excellent prognosis may be explained partially by earlier diagnosis and a higher percentage (71% vs. 33%) of patients with Stage I, II, and IV-S disease in the opso-myoclonus sub-group. However, these factors are not, of themselves, sufficient to explain totally the differences in survival rate since five of seven patients with Stage III-IV disease also exhibited long-term survival. This raises the question as to whether the neurologic dysfunction in these patients is pathogenetically related to an unknown factor (possibly autoimmune) which also controls growth and spread of the tumor.


Clear cell adenocarcinoma of the cervix and vagina. A clinicopathologic study of 21 cases with and without a history of maternal ingestion of estrogens. Twenty-one cases of clear cell adenocarcinoma of the cervix and vagina have been reviewed. Fifteen cases occurred in females under 25 years of age and four in women over 45 years. In seven cases, a positive history of maternal ingestion of diethylstilbestrol (DES) was obtained. One mother gave a history of medication with conjugated estrogens and ethisterone. Of the 13 patients with a negative history, three were born during the time period when DES was commonly used to prevent abortion. Fifteen carcinomas were cervical in origin; seven of these also involved the vagina. In six cases the carcinoma  was entirely vaginal. Vaginal involvement of the carcinomas was more common in the estrogen-related group. Two non-estrogen-related cases had coexisting congenital malformations with double uterus and vagina and unilateral renal agenesis. The histopathologic appearance was similar in both groups. In most cases, a mixture of papillary, microcystic, tubular, and solid features was seen. Vaginal adenosis was found in nine cases, six of which were estrogen-related. Surgical therapy was employed in most cases and was generally superior to radiation therapy. Five patients had lymphatic involvement. All died from carcinoma. The survival rate among sixteen patients followed for 2 years or more was 62.5%. The probable müllerian origin of clear cell adenocarcinoma is discussed. It is suggested that DES, by virtue of being an estrogen, interferes with the normal process of differentiation and degeneration of müllerian epithelium in the fetal vagina. The persistence of müllerian cells altered at the subcellular level could form the basis for development of carcinoma in later life. However, a similar sequence of events must also be accepted to occur "spontaneously" since clear cell adenocarcinoma can develop in women without a history of maternal estrogens.


Primary cardiac neurilemoma.

Primary cardiac neurilemoma. A rare case of primary cardiac neurilemoma arising in the right atrium is reported. The patient was a 55-year-old woman who was treated for 20 years with  drug and radiation therapy for a metastatic ovarian carcinoma. The cardiac tumor was an incidental finding at autopsy. Both light and electron microscopic examination of the tumor confirmed the Schwann cell origin of the neoplasm. Review of the literature reveals only one other unequivocal report of a primary cardiac neurilemoma.


Alcohol pain in Hodgkin's disease.

Alcohol pain in Hodgkin's disease. Thirty-five patients with Hodgkin's disease experienced alcohol pain. Nodular sclerosis was the predominant histological grade (77%). Alcohol pain was associated with other factors generally considered to indicate an unfavorable prognosis--systemic symptoms, Stage II disease with multiple site involvement, Stage III or IV disease. Enlargment and a rise in temperature of lymph nodes  were both present at or appeared at the site of pain in the majority (86%) of patients with this symptom.


Massive hematuria successfully treated by bladder irrigations with formalin solution. A report is presented on the use of formalin irrigation of the bladder in the management of massive hematuria in patients with inoperable tumors or as a result of radiation therapy. In 7 of 8 patients in whom this method was adopted, bleeding from the bladder stopped completely.


Chronic pain control by means of an epidural catheter: report of a case with description of the method. The feasibility of long-term epidural catheterization for control of chronic pain from sacral metastases has been demonstrated. Infection was not a problem and obstruction of the catheter did not occur. The short duration of action of currently available drugs was the major limitation of the technique. The technique described merits further investigation as an alternative to currently available methods.


Primary malignant lymphomas of the salivary glands. Primary malignant lymphomas of the salivary glands are rare, and only 43 possible cases have been reported. Four new cases from the Johns Hopkins Hospital are described, including clinical presentation, histologic findings, and subsequent course. The literature on this subject is reviewed, including cases arising in preexisting benign lymphoepithelial lesion with or without Sjögren's syndrome. Although the number of reported cases with complete documentation and follow-up information is too small for significant statistical analysis, these patients appear to have a better prognosis than the usual lymphoma patient. The possible reasons for this are discussed.


Epidermoid carcinoma of the bulbar conjuctiva in Ethiopia. We report 26 patients with epidermoid carcinoma of the bulbar conjunctiva seen in Ethiopia, in a 29-month period. The increased frequency and aggressiveness of this neoplasm is emphasized and related to increased amount and scattering of ultraviolet radiation in the tropics.


Carcinoma of the anterior tongue in adolescence. Carcinoma of the oropharyngeal region is one of the most common malignant lesions seen in western India, comprising about 47% of all cases seen at the Gujarat Cancer and Research Institute. Of these, carcinoma of the tongue has the maximum incidence. In India the ratio between carcinoma of the anterior and posterior tongue is 33:66, the reverse of that published in Europe and America. The highest incidence of carcinoma of the anterior tongue appears in males 50 to 60 years of age; only 11 cases have been reported in patients under 20 years of age. From 1969 to 1974, 218 cases of carcinoma of the anterior tongue was seen at the M.P. Shah Hospital. This paper reports five cases of carcinoma of the anterior tongue found in patients under 20 years of age. Although the anterior tongue is a visible and approachable site, all five lesions were too advanced to cure. There did not seem to be any contributory factor to produce this malignant lesion at such a young age. The patients were all male, the youngest 11 years old. Two cases were treated with surgery; one also received postoperative radiotherapy. The remaining three cases were treated with palliative radiotherapy and chemotherapy. The pathology and the current view of management are discussed.


Multiple diffuse fibrosarcoma of bone.

Multiple diffuse fibrosarcoma of bone. Light and electron microscopic observations of a case of multiple diffuse fibrosarcoma of bone are presented. Two cases of diffuse fibrosarcoma of bone have been previously reported. Clinically the tumor presented as multiple osteolytic lesions involving the pelvis bone, vertebral bodies and skull with the radiologic appearance of a multiple plasma cell myeloma. Histologically the tumor was a spindle-cell fibrosarcoma. At the ultrastructural level the tumor cells represent fibroblasts separated by a scanty amount of collagen fibers. Electron microscopic findings substantiate the fibroblastic origin of multiple diffuse fibrosarcoma of bone.


Familial colon cancer.

Familial colon cancer. Study was made of a kindred with a strong history of carcinoma of the colon. Twenty-three family members were screened for the tumor with carcinoembryonic antigen (CEA) assay, barium enema, and proctoscopy; one occult colon cancer was diagnosed. Identification and surveillance of families at high colon cancer was diagnosed. Identification and surveillance of families at high risk of cancer can provide unusual opportunities for early tumor detection.


Thymoma in a 12-year-old boy.

Thymoma in a 12-year-old boy. A case of thymoma in a 12-year-old boy is presented. The patient had a history of thymic irradiation in infancy, and a family history of leukemia. The mass was readily resected and the patient is well 10 years later. The tumor contained an unusual admixture of normal thymic tissue with the neoplastic epithelial elements. This peculiar histologic pattern is discussed in relationship to the patient's age and history.


Ganglioneuroblastoma in adults.

Ganglioneuroblastoma in adults. Ganglioneuroblastoma is a rare neoplasm of adults. Some information about the natural history and response to therapy can be obtained from two cases seen recently at our hospital and 17 cases in the literature. These tumors occur in adults of any age and are usually located in the retroperitoneum, mediastinum, or neck. Evidence of the tumor may be present years before diagnosis. Elevations of urinary catecholamines were documented in three cases and the levels correlated with progression or resection of the neoplasm. The tumor spreads either by local invasion or distant metastasis. Attempts at radiotherapy and chemotherapy in the treatment of unresectable or disseminated tumor has not resulted in objective improvement. This contrasts  with the widely reported objective successes and cures of ganglioneuroblastomas occurring in childhood. Surgical excision of localized disease was the only curative therapeutic modality in the cases we reviewed.


The role of orchiectomy in the management of advanced male breast cancer. Nine men with advanced carcinoma of the breast were evaluated after orchiectomy at the National Institutes of Health over 19 years. Of patients followed for greater than one year, five had complete remissions, one had a partial remission, and two patients did not respond to orchiectomy. The average disease-free interval was 20 months; the average survival from the time of orchiectomy in those who responded was 55.8 months and in nonresponders was 26.7 months. Orchiectomy appears to be a safe and effective way to produce an objective response and prolong survival in over 50 percent of men with advanced breast cancer.


Acute leukemia as a delayed consequence of cancer chemotherapy. Acute myelocytic leukemia occurring many years after intensive radiotherapy and/or chemotherapy has been reported in 82 patients with Hodgkin's disease, 58 patients with multiple myeloma, and 40 patients with chronic lymphocytic leukemia. The precise incidence of this occurrence is uncertain, since the total number of patients at risk is unknown. Most patients with Hodgkin's disease had received intensive radiation therapy. Many also received chemotherapy. One-third of the patients with myeloma were treated only with melphalan. Acute leukemia may occur as part of the natural history of Hodgkin's disease and multiple myeloma; it has been seen with increasing frequency in recent years due to improved survival secondary to better treatment. It is also possible that radiotherapy and/or chemotherapy may be causally related to the development of acute leukemia.


The cardiotoxicity of adriamycin and daunomycin in children. Eight (16%) of 50 children receiving adriamycin and 2 (3%) of 60 receiving daunomycin had severe cardiomyopathy with congestive heart failure. All 110 patients received cumulative doses of over 500 mg/m2. The incidence was significantly higher in those who also had incidental cardiac radiation. The electrocardiogram, with few exceptions, provided the first indication of cardiac abnormality. There were no deaths from heart failure. Two had thromboembolic episodes. Recommendations are discussed.


Radiation carcinogenesis: laboratory studies. A brief review of animal studies following external radiation suggested the following generalizations. For low LET radiation several different dose-response relationships were obtained over a wide range of doses; lengthening the time over which the radiation is given generally lowers the risk of tumor induction. For high LET radiation the dose-response relationship usually appears to be linear and lengthening the time over which the radiation is spread does not lower the risk of tumor induction. No single RBE value for high LET radiation for tumor induction can be given but current studies point in the direction of an inverse relationship between RBE value and dose. Animal studies of radiation carcinogenesis provide information of more qualitative than quantitative significance in regard to human radiation carcinogenesis.


The association between systemically administered radioisotopes and subsequent malignant disease. There is a long history recording the association of x radiation and the subsequent development of malignant tumors. For systematically administered isotopes this came into prominence when Martland discovered the association between cancer, particularly of the bone, and ingestion of radioactive isotopes by radium dial painters. This association was amplified by the development of cancer in patients given thorotrast as a contrast medium for diagnostic radiologic examination. Acute leukemia was reported 30 years ago in patients with polycythemia vera treated with 32P. Acute leukemia also occurs in patients with polycythemia vera treated only with phlebotomy or drugs. A controlled study is now underway to provide a more definite answer to question what is the incidence of acute leukemia in patients with polycythemia vera treated by phlebotomy alone, chlorambucil, or 32P. 131I for the treatment of hyperthyroidism probably does not induce cancer, but in the doses used for thyroid cancer there was an increased incidence of neoplasms (12/200 in one study). This was higher than the expected incidence of neoplasms. The doses of radioactive isotopes used currently for diagnostic purposes have not induced cancer, but it is difficult and probably impossible to verify this with absolute certainty.


The histopathologic basis for functional decrements in late radiation injury in diverse organs. As more and more patients respond favorably to combined cancer therapies, the time of survival from radiotherapy will become the most important single factor in the incidence and progression of late radiation changes. The late sequelae of irradiation are the sum of the following: 1) residua of the direct and indirect early changes in responsive cell populations; 2) progressive vascular sclerosis with its associated effect upon connective tissue and the parenchymal cells; and 3) the reactive or replacement connective tissue proliferation which is responding to 1) and 2). From this it may be seen that further investigative efforts need direction toward: 1) reducing the magnitude and permanence of the early principal parenchymal cell injury; 2) diminishing the severity of the early microvascular change which adds significantly to the early parenchymal cell damage; 3) determining the mechanics of the progressive vascular sclerosis with a view to retarding this effect; and 4) lessening the reactive fibrosis.


Residual disabilities in children treated for intracranial space-occupying lesions. A retrospective study of 30 long-term survivors of cranial or craniospinal irradiation for intracranial space-occupying lesions has demonstrated physical and mental handicaps in the majority. This is most severe in those cases treated before the age of 11 years, and is not confined to those children having craniospinal or whole-brain irradiation. The mental handicap also appears to be progressive, but cannot be easily examined in this retrospective study.


Late effects of therapeutic irradiation on the skeleton and bone marrow. Sequelae in the skeleton and bone marrow can be important late consequences for survivors following radiation therapy of cancer. Skeletal sequelae of radiation therapy often are predictable, although they may not be avoidable. The growth suppressive effects of therapeutic irradiation may occur in any bone, but most often are noted in the spine after doses in excess of 2000 rads. Mature bone and cartilage may be devitalized by irradiation without clinical consequence until stressed. Although malignant tumors may arise in irradiated bone and cartilage, the risk is minimal and is readily accepted in modern-day radiation oncology. Radiation-induced suppression of bone marrow function usually is of immediate rather than late consequence; however, functional recovery after therapeutic irradiation, while prolonged, is more complete than formerly thought. Leukemia rarely develops secondary to therapeutic irradiation.


Decreased risk of radiation-associated second malignant neoplasms in actinomycin-D-treated patients. One hundred two long-term survivors of childhood cancers with second malignant neoplasms (SMNs) were collected from 10 institutions. Forty-seven cases fulfilling study criteria were studied to determine the risk of developing a SMN in irradiated fields after exposure to various chemotherapeutic agents. The case control method was used. The risk of developing such tumors was decreased by a factor of 7 in patients receiving actinomycin-D (AMD). The "protective" effect of AMD was more pronounced in patients receiving repeated courses of the agent. No change in relative risk was found for children given antifolates, the vinca alkaloids, or alkylating agents. AMD "protection" is an unexpected finding because the agent is an oncogen in animals and an enhancer of radiation, the latter being a known carcinogen. Possible mechanisms, which remain speculative, are discussed. These results indicate the need for careful long-term observation of cancer survivors to gain understanding of the late effects of multimodal treatments.


Acute and late effects on normal tissues following combined chemo- and radiotherapy for childhood rhabdomyosarcoma and Ewing's sarcoma. Twenty-three patients with rhabdomyosarcoma and 15 patients with Ewing's sarcoma, treated with radiation therapy to the local site and systemic multiagent chemotherapy are described. Acute reactions from combination chemotherapy and radiation therapy were noted in both groups of patients. These reactions often appeared after low doses of irradiation, required unplanned interruptions of treatments, and in some patients, led to discontinuation of radiation therapy. The chronic effects on normal tissues in both groups of patients have been severe in several cases.


Late effects of cancer therapy: the role of the clinical pharmacologist. The clinical pharmacologist, by increasing our knowledge of the molecular mode of action of drugs and their specific anticancer mechanisms, can help to predict which therapies would be expected to have late effects that were progeric, infectious, or oncogenic, and in which organs such effects could arise. By insisting upon the inclusion of appropriate controls, the pharmacologist can help attribute any observed late effects to a primary host-disease diathesis, or to the direct effects of therapy, or to the indirect effects of prolongation of the life of the host. Finally, by participating in the design and including appropriate control groups from the start of new clinical trials, the clinical pharmacologist can help restrict clinical therapies whose antitumor effects are absent or small but whose late toxic potentials are high.


Bacillus Calmette-Guérin vaccination and cancer prevention: a critical review of the human experience. Published studies of the cancer experiences of children vaccinated with Bacillus Calmette-Guérin in antituberculosis programs were reviewed and the strengths and weaknesses of each evaluated. There is little evidence that vaccination outside of the neonatal period is effective. If there is an effect of neonatal vaccination, it must convey only a small amount of "protection." Follow-up studies adequate to assess the long-term effects of such vaccination, particularly the risk of lymphoma, have not been done, and recent evidence indicates that such evaluation is warranted.


Current epidemiological evidence for transmission of Hodgkin's disease. The epidemiological evidence relating to the possibility of person-to-person transmission of Hodgkin's disease is reviewed. A number of studies are found to be difficult to interpret because of the absence of control data. It is concluded that, although certain studies are consistent with the hypothesis of person-to-person transmission, the evidence is a present weak and further epidemiological studies are needed.


Evidence for infectious component of Hodgkin's disease and related considerations. The four epidemiological approaches used to evaluate the hypothesis that Hodgkin's disease might have an infectious component are reviewed. The limitations of each approach are summarized and some related questions are raised. The emerging picture for Hodgkin's disease is that a variety of factors, both environmental and genetic, might be important in the etiology of this disorder.


An animal model for DNA-RNA virus interaction based upon virological and histological findings. The presence of endogenous oncornavirus and herpesvirus in guinea pigs has been established. The oncornavirus apparently is present in all guinea pigs but is expressed only under certain conditions. Expression of the latent herpesvirus is generally age and strain dependent as is the development of spontaneous guinea pig leukemia. Following special laboratory manipulation, expression of both virus types was accomplished in vitro. Studies of the role played by these two virus types in the development of neoplastic disease in guinea pigs revealed that, in the presence of the endogenous oncornavirus, a superinfection with herpesvirus led to the development of self-limited lymphoproliferative changes. Together with the studies reported by other investigators, it appears that interaction between the DNA and RNA viruses may play an important role in the natural occurrence of viral oncogenesis. Guinea pigs provide an intriguing animal model for the study of herpesvirus and oncornavirus interaction both in vivo and in vitro.


Epstein-Barr virus behavior in different populations and implications for control of Epstein-Barr virus-associated tumors. The epidemiology of Epstein-Barr virus (EBV) infection in populations at different risk for EBV-associated diseases indicates significant differences between the populations. EBV infection takes place much earlier in Uganda, where all children are infected before the age of 2 to 3 years, than in Southeast Asia, where nasopharyngeal carcinoma is prevalent. It is proposed that such early infection in Equatorial Africa is related to the risk for Burkitt's lymphoma. Four possible interventions to control EBV-associated diseases are presented: (a) simple hygienic measures to delay natural primary infection by EBV; (b) EBV vaccine; (c) intervention against cofactors such as malaria in Burkitt's lymphoma; and (d) characterization of high-risk groups to allow early detection and successful treatment.


In vivo and in vitro studies of immunotherapy of nasopharyngeal carcinoma with transfer factor. Epstein-Barr virus, the apparent cause of infectious mononucleosis, may also be an etiological agent in nasopharyngeal carcinoma and Burkitt's lymphoma. Lymphocytes from normal individuals with anti-Epstein-Barr virus antibody activity may be sensitized to Epstein-Barr virus and contain transfer factor with the potential to program and/or recruit other lymphocytes to react against the virus and/or viral antigens. A patient with nasopharyngeal carcinoma refractory to conventional therapy was treated with transfer factor obtained from normal, young adults with previous history of infectious mononucleosis. Following immunotherapy, apparent slowing of tumor growth was observed, which was associated with intense lymphocytic infiltration of the tumor and reconstitution of delayed cutaneous hypersensitivity reactions to microbial recall antigens. A double-blind randomized clinical trial has been initiated to determine whether transfer factor immunotherapy is a useful adjunct to radiotherapy in the primary treatment of patients with nasopharyngeal carcinoma. If successful, a similar trial might be considered for African patients with Burkitt's lymphoma.


Murine and rat mammary tumors as models for the immunological study of human breast cancer. The human breast cancer process and some aspects of experimental mammary cancer are compared in the light of Huxley's hypothesis that each neoplastic cell line may be viewed as a new obligate parasitic species derived from metazoan cells. Sufficient correlations are found to justify the hope that the viral-induced mouse mammary oncogenic process and the carcinogen-induced rat mammary system may serve as reasonable models of the human disease for immunological studies.


In vitro immune responses to viral and tumor antigens in murine breast cancer. Inhibition of migration of peritoneal exudate cells proved to be a useful measurement of cell-mediated immunity which correlated in several respects with blastogenic transformation reactions. Lectins (phytohemagglutinin and concanavalin A) inhibited the migration of peritoneal exudate cells from normal and tumor-bearing mice, whereas tumor antigen caused inhibition of migration of cells from tumor-bearing animals only. The disparity in immunogenic capacity previously observed with lymphocyte transformation studies was also manifested in migration inhibition, i.e., D1-DMBA-3 tumor being immunogenic and D1-DMBA-2 being nonimmunogenic. Using the migration inhibition and blastogenic transformation reactions, responses were obtained to mammary tumor virus (MTV) antigen(s) in cells from BALB/cCrgl mice, which are free of MTV. In contrast, cells from MTV-positive BALB/cfC3H mice failed to respond to this antigen(s) in both reactions, suggesting a form of tolerance. However, the reactions became positive after implantation with MTV-containing spontaneous mammary tumors. Two possible explanations of the origin of reactive lymphocytes, horizontal transmission, or activation of a gene coding for an MTV antigen(s), are discussed.


Microcytotoxicity assay of immune responses to non-mammary tumor virus-induced, preneoplastic, and neoplastic mammary lesions in BALB/c mice. Using a microcytotoxicity assay we have studied the immune responses to the preneoplastic, hyperplastic alveolar nodule (HAN) lines D1 and D2 and to the mammary tumors arising spontaneously from them in BALB/c mice. Lymph node cells (LNC) from mice bearing HAN implants, or from mice whose implants had been removed greater than 1 week prior to testing, failed significantly to inhibit survival of HAN cells in culture. Specific inhibition of HAN cells was found, however, in 9 of 28 experiments with LNC from mice whose implants had been removed within the week of testing, and not with LNC from sham-operated controls. On the other hand, increased survival of HAN cells was also seen with LNC from sensitized, as opposed to normal, mice. This was more frequent for tests with D1 than with D2 HAN cells (38 versus 9%) and when the LNC donors were still bearing HAN IMPLANTs (60% of tests versus 27% when implants removed). Following sensitization by implantation and subsequent removal of D1 or D2 tumors, LNC-mediated inhibition of tumor cell survival, specific for each tumor, was found in about 25% of the tests. Increased survival of tumor cells, however, was seen in 30 to 40% of the tests. This increased survival cross-reacted between D1 and D2 tumors and between D1-D2 and mammary tumor virus-induced tumors, but not between D1-D2 and chemically induced mammary tumors or fibrosarcomas. Increased survival could be blocked by sera from sensitized mice. In contrast to mammary tumor virus-induced mammary lesions, the immune responses to D1 and D2 HAN lines and tumors are "weak" and indeed perhaps stimulate hyperplastic and neoplastic cell survival.


Regulatory approach toward vaccines against cancer: the benefit/risk ratio. Decisions regarding investigational new drug applications for testing of all biologicals to be used in humans, including those designed to prevent or treat cancers, must be considered in terms of benefit/risk ratios. In order for a regulatory organization to make the appropriate decision regarding the testing of new biologicals in humans, it must have an extremely broad dialog within the critical scientific public and the general public, which are represented on committees functioning in the Bureau of Biologics. There must be a generaly consensus regarding the benefit/risk ratio of proposed new biologicals for scientific progress and the effective regulation of biologicals.


Long-term organ culture of human bronchial epithelium. Human bronchial epithelium has been maintained in organ culture in serum-supplemented medium for 4 months. After 4 to 6 weeks in culture, various changes in morphology were apparent. There was an increase in autophagic vacuoles in mucous, ciliated, and basal cells, a reduction in the height of the columnar cells, a decrease in the number of goblet mucous cells, and an increase in cells with small mucous granules. After 3 months in culture, the basal lamina was frequently covered by 2 or 3 layers of epithelial cells consisting of nonkeratinizing squamous cells with short microvilli and small mucous granules. Less frequently, keratinizing squamous cells were seen. Differentiated epithelium incorporated precursors into macromolecules in serum-free medium, supplemented with vitamin A, at 1 week of culture. These explants exhibited changed epithelium by 2 weeks, similar to that described for epithelium in serum-supplemented medium after 4 to 6 weeks.


Binding of (3H)benzo(a)pyrene to DNA in cultured human bronchus. The studies reported here demonstrate some of the factors affecting the binding of benzo(a)pyrene (BP) to macromolecules in cultured human bronchial mucosa. Bronchial specimens were obtained at either surgy or "immediate" autopsy from patients with and without lung cancer. Grossly normal-appearing pieces of bronchus were cultured in a chemically defined medium, i.e., CMRL 1066 medium containing 1 mug insulin per ml, 0.1 mug beta-retinyl acetate per ml,, 0.1 mug hydrocortisone hemisuccinate per ml, 2 mM L-glutamine, 100 units penicillin G per ml, and 100 mug streptomycin per ml. After 7 days, explant cultures were exposed to [3H]BP, usually for 24 hr, and then binding to total cellular macromolecules was studied by autoradiography, and binding to DNA was measured following isolation of DNA from bronchial mucosal cells. The extent of binding of [3H]BP was dependent on dose of BP, length of exposure to [3H]BP, and temperature. By autoradiography, bronchial epithelial cells bound more [3H]BP than stromal fibroblasts. Both 7,8-benzoflavone and butylated hydroxytoluene appeared to reduce the level of [3H]BP bound to DNA, while nicotine apparently did not alter the level of binding. These studies demonstrate that the bronchial mucosa, an important human cancer target tissue, has the capability to form metabolites of BP which bind to macromolecules including DNA. In addition, 7,8-benzoflavone and butylated hydroxytoluene, both known to alter the microsomal metabolism of BP, reduce the level of [3H]BP bound to DNA.


Synergism between neutron radiation and diethylstilbestrol in the production of mammary adenocarcinomas in the rat. When young female A X C rats were given 9.6 rads of 0.43-MeV neutrons, 32 of 33 survived a 50-week follow-up period, 2 rats developed a total of 3 mammary adenocarcinomas, and 3 rats developed a total of 4 mammary fibroadenomas. For 25 rats implanted with a 20-mg pellet containing 5 mg diethylstilbestrol and 15 mg cholesterol, average survival was 284 days; 22 rats developed a total of 182 mammary adenocarcinomas, and 21 rats developed a pituitary tumor. When diethylstilbestrol was given 2 days before neutron radiation to 35 rats, the average survival was 239 days; 32 rats developed a total of 842 mammary adenocarcinomas, 1 rat developed a single mammary fibroadenoma, and 34 rats developed a pituitary tumor. All of the 31 control rats survived the 50-week study period, and none developed tumors. Twenty-one of the rats that received both diethylstilbestrol and neutron radiation and 1 rat that received only diethylstilbestrol exhibited a multiple mammary adenocarcinoma response with a range of 18 to 72 mammary adenocarcinomas per rat. These results were interpreted to mean that a synergistic interaction between diethylstilbestrol and neutron radiation on mammary adenocarcinoma formation occurs in terms of an earlier onset and a larger number of mammary adenocarcinomas. These results confirm and complement a previously reported synergistic interaction between diethylstilbestrol and X-radiation on mammary adenocarcinoma formation in A X C female rats.


Detergent lysis for isolation of intact polysomes of Nivikoff hepatoma ascites cells. An efficient, rapid procedure for the isolation of polysomes from Novikoff hepatoma ascites cells that avoids mechanical shear was developed, and Ivory was used as the detergent to lyse the cells. This method yields classes of large polysomes and 3- to 5-fold increased yields over that of routine homogenization procedures. Up to 70% of the polysome population is larger than tetramers. The polysomes and ribosomes are morphologically intact and contain undegraded ribosomal RNA and biologically active messenger RNA. This procedure also yields nuclei free of cytoplasmic contamination as a by-product of polysome isolation. These nuclei do not show evidence of protein degradation and are enzymatically active with respect to RNA polymerases I and II.


A transient thermotolerant survival response produced by single thermal doses in HeLa cells. Continuous exposure of HeLa cells in culture to elevated temperatures (41-45 degrees) results in cell killing which increases exponentially as the time at the elevated temperature increases linearly. When cells are returned to 37 degrees after an initial thermal dose, cellular sensitivity to subsequent hyperthermic doses is reduced. Cell inactivation rates for cultures previously treated with 44 degrees for either 0.5 or 1 hr followed by incubation at 37 degrees for 2 hr, showed D0's of 1.1 and 1.5 hr, respectively, for subsequent thermal treatments at 44 degrees. Cultures receiving no prior hyperthermic dose had a D0 of 0.5 hr for treatments at 44 degrees for up to 3.5 hr. The viable progeny of cells treated with 44 degrees for 1 hr, however, had the same sensitivity to thermal doses at 44 degrees as did previously unheated cells. These results and others demonstrate that (a) single thermal dose produce a state of thermotolerance in HeLa cells to subsequent hyperthermic doses; (b) the degree of thermotolerance produced is dependent on the magnitude (i.e., temperature and time at the elevated temperature) of the first thermal dose; (cy thermotolerance does not develop at the elevated temperature but requires a return of culture temperatures to 37 degrees; (d) cellular acquisition of thermal tolerance is dependent on cell metabolism, as demonstrated by an inhibition of the effect at 0 degrees; and (e) this effect is a transient phenomenon which is lost as cells divide following the first thermal dose.


Effects of N-acetoxy-2-acetylaminofluorene and N'-nitro-N-nitrosoguanidine on nuclear DNA synthesis in rat liver. A system for the study of DNA synthesis in isolated nuclei is described for sham and regenerating rat liver. The system has been characterized with respect to nuclear purity, conditions for optimum incorporation of [5-methyl-3H]thymidine triphosphate, time course of incorporation, product analysis by neutral and alkaline sucrose gradients, and the effect of exogenously added DNA. No difference in the basal level of activity was detected between nuclei prepared from normal or regenerating liver when isolated 24 hr after operation. However, exogenous activated DNA preferentially stimulated [5-methyl-3H]thymidine triphosphate incorporation in nuclei from regenerating liver. Activated DNA caused to react with the carcinogen N-acetoxy-2-acetylaminofluorene was a less effective primer-template in this system and decreased in a dose-dependent fashion the incorporation of [5-methyl-3H]thymidine triphosphate to below basal levels in nuclei from both normal and regenerating liver. The carcinogen N-methyl-N'-nitro-N-nitrosoguanidine had no inhibitory effect when assayed in this fashion.


Metastasizing tumors from serum-supplemented and serum-free cell lines from a C57BL mouse lung tumor. A tissue culture cell line was established from an alveologenic lung carcinoma from a C57BL/lcrf-at mouse. The cells can be maintained in a completely defined serum-free medium. Tumors derived from the tissue culture cells grown in serum-free or serum-supplemented medium give rise to lung metastases. The ultrastructure of the tissue culture cells in both media is similar to that of spontaneous or induced alveologenic mouse lung tumors.


Isonucleolinosis in cell cultures of human meningiomas. In cell cultures of 13 human meningiomas the internal structure of the nucleolus was stained by the toluidine blue-molybdate method and compared with the karyotype of the tumors. Although some of the meningiomas had lost or gained one or more chromosomes and had undergone structural aberrations, all of them showed isonucleolinosis, which is normally found only in cells with normal karotype. It seems possible that the occurrence of iso- or anisonucleolinosis is not a specific sign of euploidy or aneuploidy, but of benignity or malignancy of the examined tissue.


Purification, analysis, and subunits of myeloma (MOPC 21) DNA-dependent RNA polymerase A (1) by polyriboadenylate-sepharose. DNA-dependent RNA polymerase A (or 1) was purified from murine myeloma MOPC 21 by diethylaminoethyl Sephadex chromatography. Further separation from DNA polymerases, protein kinase and DNA endonuclease was accomplished by polyriboadenylate-Sepharose affinity chromatography followed by gradient centrifugation. Yields following chromatography were 100%, but following gradient centrifugation only 25 to 30% of the activity remained. Addition of low-molecular-weight components increased yields to 50 to 60%. Several species of myeloma polymerase A could be detected, and subunits of 190,000 and 125,000 daltons were identified. No evidence of phosphorylation of the polymerase was found.


Alkylating properties of phosphoramide mustard. The relative alkylating activities of two of the cytotoxic metabolites of cyclophosphamide, phosphoramide mustard and nornitrogen mustard, have been studied at pH 4.6 and 7.4. The products formed on alkylation of ethanethiol by these metabolites have been identified, confirming that phosphoramide mustard undergoes alkylation reactions as an intact molecule. Deuterated analogs of the two metabolites have been synthesized, namely N,N-bis(2,2-dideutero-2-chloroethyl)-phosphorodiamidic acid and N,N-bis(2,2-dideutero-2-chloroethyl)amine and used to determine that alkylation proceeds directly via an aziridinium intermediate rather than a direct SN2 displacement of the chlorine atom.


Close reproduction by different laboratories of characteristics of circadian rhythm in 1-beta-D-arabinofuranosylcytosine tolerance by mice. The tolerance of BALB/c X DBA/2 F1 mice to the popular cytostatic drug 1-beta-D-arabinofuranosylcytosine (ara-C) was tested in two laboratories about 1000 km apart. According to the same plan and on the same days in Little Rock, Ark., and Minneapolis, Minn., nine groups of 20 mice each received four courses of ara-C treatment, with 4-day intervals between them beginning February 7, 1973. In each course, a total dose of 240 mg/kg was divided among eight separate injections administered at 3-hr intervals. One group of mice received equal doses of ara-C every 3 hr (the homeostatic schedule). The eight other groups in each location received the same total dose per course but in gradually increasing and decreasing doses (the sinusoidal schedule). The timing of the highest doses on the latter schedule differed among the eight groups (by integer multiples of 3 hr). As predicted from earlier work, survival times after treatment with ara-C on different sinusoidal schedules differed drastically. However, the timing of the sinusoidal schedules yielding the longest survival was similar in the two locations. The survival times from all sinusoidal treatments from a given location were fitted by a 24-hr cosine curve. The timing of the rhythm in tolerance as a whole as thereby computed as the lag from local midnight of the peak in the cosine curve best fitting all data. The timing of this tolerance rhythm (briefly, circadian chronotolerance), computed separately for data from Arkansas and Minnesota, agreed within 1 hr. There also was close agreement in the results obtained by the 2 laboratories in mean survival time; the percentage of survivors when mice were treated according to certain of the selected sinusoidal schedules was much greater than for mice treated on the homeostatic schedule. This large and reproducible difference in tolerance and the similar timing of the overall fitted function describing chronotolerance in the hands of different investigators underlines the urgency of testing potential benefits from timed clinical treatment.


Electron spin resonance spin-label studies of intercalation of ethidium bromide and aromatic amine carcinogens in DNA. A spin-labeled technique has been developed for the study of carcinogen-DNA intercalation mechanisms utilizing a modified ethidium bromide as a model ligand and specifically synthesized spin labels of carcinogenic aromatic amines such as 2-aminofluorene, 2-aminoanthracene, and 6-aminochrysene. The technique takes advantage of the characteristic electron spin resonance anisotropy of the corresponding spin labels complexed with DNA. Analysis of the orientation-dependent information thus obtained has clearly shown that the lignad moieties in all 4 respective complexes are accommodated in adjacent base-pair layers of the DNA with the nitroxide reporter oriented in 1 preferential direction. The geometry of the nitroxide rings with respect to their respective constraining ligands in a particular complex appeared to be largely dependent upon the size of the ligand moiety and the position of the reporter attachment on the ligand molecule. A coplanar configuration is most favored for the spin labels in which the ligand moiety per se is a 3-fused ring with the nitroxide substituted at a position on or close to the longitudinal end of the ligand molecule. Temperature studies in which the heat-induced release of the bound label is monitored by electron spin resonance gives an accurate measure of the complex dissociation characteristics that appear to parallel the helical coil cooperative melting transition monitored by absorbance measurements. The extent of dissociation of the bound spin labels parallels almost exactly the melting, i.e., unzipping of the DNA double helix, suggesting that the spin labels are immobilized by intercalation at the site on the DNA directly involved in the maintenance of the double helical structure. Analysis of the electron spin resonance spectra of the complexes in terms of the extent of immobilization indicates that, for aromatic amine spin labels, two different binding species exist, one strongly immobilized presumably at a guanine-cytosine base-pair region and the other partially immobilized in a region other than guanine-cytosine base pair. Competitive binding of the labels with respect to their parent ligand and binding isotherm results show that nitroxide substitution does not affect the type of binding but does affect the extent of binding, i.e.. binding constant with the labeled compound having a lower affinity.


The age-dependent efficacy of polyadenylic-polyuridylic acid therapy upon the development of spontaneous leukemia in AKR mice. The synthetic double-stranded polynucleotide, polyadenylic-polyuridylic acid, has been shown to increase the long-term survival of AKR mice. In order to determine whether this effect was age dependent, polyadenylic-polyuridylic acid was administered to AKR mice starting at 2, 4, 6, or 8 months of age. The best therapeutic effect was achieved when polyadenylic-polyuridylic acid treatments were begun at 2 months of age, and there was no beneficial effect when begun at 8 months of age.


The influence of tumor volume and the degree of heating on the response of the solid Yoshida sarcoma to hyperthermia (40-42 degrees). The solid Yoshida sarcoma implanted on the feet of rats was subjected to local hyperthermia by water bath immersion. Tumor response was governed by the temperature and duration of heating (i.e., the degree of heating) and by tumor volume. With small tumors (1.0- to 1.5-ml volume) an intratumor temperature of 42 degrees maintained for 1 hr led to tumor regression in 11 to 13 days, and the tumor volume was halved every 2.6 days. Following 2 hr hyperthermia (42 degrees) the tumors disappeared in 6 to 7 days, and tumor volume was halved every 1.2 days. Tumors of 2 to 3-mol volume had left the exponential phase of the growth curve and required 2 hr at 42 degrees for cure. Following heating at 40 degrees for 1 hr, there was a 50% increase in O2 uptake and anaerobic CO2 production by the tumor, accompanied by enhanced dissemination by lymphatic, vascular, and direct routes, and tumor was found in organs not usually the site of metastases (e.g., testis and stomach). With large tumors (3.0 to 4.5 ml), the survival time of the rats was significantly reduced. These results occurred in the absence of a rise in body temperature of the animals. It is concluded that in this animal-tumor system, hyperthermia at a temperature inadequate for tumor destruction (40 degrees) can result in changes in the tumor that represent a hazard to the host.


Polyadenylic acid content and electrophoretic behavior of in vitro released RNA's in chemical carcinogenesis. Cytoplasmic RNA from control and thioacetamide-intoxicated rat livers was compared with regard to components separated by polyacrylamide electrophoresis and for the proportion containing polyadenylic acid segments. A further comparison was made with the RNA's released from rat liver nuclei in vitro. Exposure in vivo to thioacetamide was associated with more cytoplasmic RNA's with migrations of 9 to 16 S and with both an acute and prolonged increase in the relative quantity of polyadenylic acid-containing polyribonucleotides. Incubation of control nuclei in vitro was associated with a leakage of approximately 1 to 2% of nuclear RNA with a major migration band at 9 S. Addition of adenosine 5'-triphosphate increased the transport 20-fold, and 9 and 16 S species were transported as well as a 4 S group. Following exposure to thioacetamide, an enhanced "leakiness" released 9 S RNA. Addition of adenosine 5'-triphosphate doubled the quantity of released RNA, which consisted of 9 and 4 S species. Both leaked and adenosine 5'-triphosphate-transported RNA's contained polyadenylic acid segments in roughly 20% of the macromolecules. These studies extend the observation of less stringent control of RNA release and transport in carcinogen exposure and suggest the potential usefulness of the in vitro release system for assaying cellular regulatory phenomena.


The significance of hematogenous tumor cell clumps in the metastatic process. The relationship between the size distribution of vessels in an implanted tumor, the size distribution of tumor cell clumps collected in the venous effluent of the tumor, and the development of pulmonary metastases have been studied. The purpose is to evaluate the importance of clumps and their site of formation in the metastatic process. The results demonstrate a negative exponential character for both the size distribution of effluent tumor clumps and the tumor vessel population. Tumor trauma or massage increases total tumor cells and clumps released into the effluent. Serial amputation demonstrates that tumor cells are continuously being released on a day-by-day basis in vivo. A linear relationship exists between the proportion of vessels with diameters large enough to pass a tumor clump of a given size and the proportion of clumps of that size within the venous effluent. Injection of tumor cells in clumps of 6 to 7 cells produces a significantly greater number of metaststic foci than does a similar number of single tumor cells; larger clumps produce significantly more metastatic foci than do smaller clumps matched for the number of cells. These studies verify the significance of tumor clumps in the metastatic process. It is suggested that tumor cell clumps arise locally within the vascular bed of the tumor.


The 7.1 S nuclear DNA polymerase and DNA replication in intact liver. Just as after 70% hepatectomy, the activity of the 7.1 S DNA polymerase, but not the 3.2 S polymerase, is elevated in liver nuclei from unoperated animals in which hepatic DNA replication has been induced with a mixture of biochemicals or by a dietary manipulation. Again as with regenerating liver, the stimulated intact livers show a relationship between the increases in the enzyme activity and thymidine incorporation in vivo over a wide range of hepatic responses. These observations are consistent with a role for the 7.1 S activity in nuclear DNA replication. Cytosine arabinoside 5'-triphosphate and novobiocin can be used to distinguish between the 3.2 S and 7.1 S polymerases from nuclei of stimulated intact liver as well as of regenerating liver.


High-pressure liquid chromatographic separation of 10 benzo(a)pyrene phenols and the identification of 1-phenol and 7-phenol as new metabolites. The separation of ten isomeric benzo(a)pyrene phenols has been accomplished by the use of high-pressure liquid chromatography utilizing a newly developed recycling technique and new column and solvent systems. Using this new system and comparing the metabolites obtained with authentic standards, we have isolated 1-hydroxybenzo(a)pyrene and 7-hydroxybenzo(a)pyrene and identified them as metabolites formed by rat liver microsomes. In previously reported chromatography systems, the new metabolites migrated with another metabolite, 3-hydroxybenzo(a)pyrene.


Increased cell killing by metronidazole and nitrofurazone of hypoxic compared to aerobic mammalian cells. Nitromidazole and nitrofuran derivatives comprise a large family of compounds, some of which have been shown to be hypoxic cell specific radiosensitizers in vivo and in vitro. The effects of metronidazole (2-methyl-5-nitroimidazole-1-ethanol) and nitrofurazone (5-nitro-2-furaldehyde semicarbazone) were studied on cell viability in vitro in the presence of air or nitrogen in the absence of radiation. Exponential-phase Chinese hamster ovary cells were placed in suspension culture in complete medium in the presence of air, made hypoxic by flowing nitrogen (less then 0.001% oxygen), and exposed to various concentrations of these drugs. As a function of time, aliquots were removed and plated to determine cell viability. After 8 hr of incubation of Chinese hamster ovary cells in 29 mM metronidazole or 500 muM nitrofurazone, the absolute plating efficiency remains relatively constant (80 to 40%) in the presence of air. In contrast, under hypoxic conditions the plating efficiency of the cells dropped to 1% after 6 hr of incubation in 29 mM metronidazole or 500 muM nitrofurazone. This phenomenon of hypoxic cell specific toxicity was found to be dependent upon cell type, concentration of drug, temperature of incubation, and oxygen concentration. The results of these experiments indicate an increased toxicity of these drugs under hypoxic conditions and suggest that further investigation into the mechanism and specificity of these effects is warranted.


Glutathione-S-epoxide transferase activity during development and the effect of partial hepatectomy. The specific activity of glutathione-S-epoxide transferase with styrene oxide and 3-methylcholanthrene-11, 12-oxide was determined in rat liver and lung during development from the fetal to the adult stage and after partial hepatectomy. Enzyme activity in fetal liver or lung at 18 days of gestation was about 20% of that observed in the adult; it rose rapidly to the adult value by 21 days of age. Hepatic enzyme activity was reduced to 50% of control values by 12 hr after partial hepatectomy; enzyme activity returned to control values by 48 hr. No diurnal variation in the activity of glutathione-S-epoxide transferase was observed in rat liver.


The effect of levamisole on cell-mediated immunity and suppressor cell function. The immunopotentiating drug, levamisole, was found to augment human lymphocyte responses to allogeneic cells and plant mitogens in vitro. The effect was critically dose dependent and, at high doses, suppression rather than augmentation of the immune response was observed. Our hypothesis that augmentation of immune responses by the drug is due to the selective impairment of immunoregulatory suppressor activity was tested in a model using human splenic and thymic suppressor cells. Contrary to expectation, the drug was found to be capable of augmenting suppressor activity rather than abolishing it. It is concluded that levamisole is a nonspecific stimulator of lymphocyte function, irrespective of the role played by these cells in the human response.


Evaluation of vitamin A analogs in modulating epithelial differentiation of 13-day chick embryo metatarsal skin explants. Seventeen vitamin A compounds were evaluated in organ culture for activity in altering epithelial differentiation of metatarsal skin explants from 13-day-old chick embryos. The explants keratinized in 6 to 8 days and, when cultured in the presence of beta-retinoic acid (RA), inhibition of keratinization occurred and a mucous metaplasia developed. A cyclopentenyl analog of retinoic acid was approximately 10-fold more effective than RA in producing mucous metaplasia. Six other analogs exhibited about the same activity as RA: trimethylmethoxyphenyl analog of retinoic acids, alpha-retinoic acid, 13-cis-retinoic acid, methyl retinoate, ethyl retinoate, and N-ethylretinamide. The following 5 vitamin A compounds were about one-fourth as effective as RA: the trimethylmethoxyphenyl analog of ethylretinamide, the phenyl analog of retinoic acid, the trimethylmethoxyphenyl analog of ethyl retinoate, beta-retinyl acetate, and retinol. The furyl analog of retinoic acid and N,N-diethylretinamide were approximately one-tenth and one-fifteenth less effective than RA in inhibiting keratinization. The analog, alpha-retinyl acetate, was about one-hundredth as effective as RA and the pyridyl analog of retinoic acid (2.5 X 10(-5) M) did not inhibit keratinization. Since the property of altering epithelial differentiation may be a fundamental requirement for the prophylaxis and/or treatment of malignant epithelial lesions, this system can be used to determine whether the new synthetic analogs of vitamin A are active in modulating epithelial differentiation.


The influence of retinyl acetate on the postinitiation phase of preneoplastic lung nodules in rats. The effects of retinyl acetate (RA) on the development of carcinogen-induced metaplastic lung nodules were investigated. Four mg of 3-methylcholanthrene were administered intratracheally to F344 rats maintained on a vitamin A-free diet and receiving 31.4 nmoles of RA per week by intragastric intubation. At 3, 5, and 10 weeks after intratracheal instillation of 3-methylcholanthrene, one group of 24 rats each was started on a weekly dose of 31,400 nmoles of RA; a control group was continued on the low-RA dose. Fifty-two weeks after 3-methylcholanthrene injection, the incidence of metaplastic lung nodules was found to be 3% in the combined high-RA-dose groups as compared with 42% in the low-RA-dose group. It is therefore concluded that RA has a significant effects on the postinitiation phase of preneoplastic lung nodules in rats.


The relationship of polyamines in cerebrospinal fluid to the presence of central nervous system tumors. Cerebrospinal fluid (CSF) polyamine concentrations were assayed in patients with and without central nervous system tumors, using a high-pressure liquid chromatographic technique. Definite elevations were found in the CFS polyamine concentrations of patients with untreated malignant central nervous system tumors when compared with those concentrations observed in the CSF of patients without neoplasia. Patients undergoing successful tumor therapy for malignant central nervous system tumors showed CSF polyamine concentrations that closely approximated the concentrations found in the CSF of patients without tumor.


Ultrastructure of a murine mammary carcinoma exposed to hyperthermia in vivo. The ultrastructural changes following local hyperthermic therapy was studied in a solid murine mammary carcinoma. A few hr after treatment, a pronounced lysosomal activity was observed in the cytoplasm of the tumor cells, together with mitochondrial destruction and disaggregation of the polyribosomes. Later, more destructive changes with intense cell shrinkage and cytoplasmic lysis occurred, and within 24 hr the entire cytoplasm of all the tumor cells was completely destroyed. In the nuclei shrinkage and condensation of heterochromatin were early features. The nucleoli were gradually degranulated, but with preservation of the fibrillary component. However, here, too, complete destruction occurred within the first few days after treatment. Cells in mitosis were also arrested and destroyed in the same way. The nonmalignant cells of the tumor tissue presented only minor reversible morphological changes, and within a few days the tumor area was replaced by ingrowth of fibroblasts and macrophages. The morphological changes are discussed in the light of our present knowledge of the hyperthermic effect on tumor cells. As regards the mechanism of hyperthermic destruction of solid tumors in vivo, the hypothesis is advanced that a primary, lysosomally conditioned, selective destruction of the malignant cells occurs and that this reaction is intensified by a high acidity in the tumor milieu.


Contrasting pulmonary blood flow profiles in children with atrial and ventricular septal defects. Instantaneous pulmonary blood flow profiles and other measures of haemodynamic functioning were studied in children with atrial septal defects (ASD) and children with ventricular septal defects (VSD) and normal pulmonary pressures and resistance at the time of defect closure. Though most parameters measured were comparable in the patient populations, several significant differences were found in the shape of the flow profile.


Influence of frequency of atrial contraction on coronary blood flow and ventricular performance in the conscious dog with myocardial infarction. The effects of alterations in the frequency of contraction on coronary blood flow and ventricular performance were studied in 12 conscious, unsedated dogs with established myocardial infarction. Total and regional coronary blood flow was measured using radioactive microspheres. The peak increase in flow to the right ventricle was 71% to the infarcted area of the left ventricle was 72% to the non-infarcted area of the left ventricle was 90% and to the ventricular septum was 104%. Despite the generalized increases in regional myocardial blood flow, flow tended to decrease to the subendocardial portion of the infarcted area of the left ventricle. The peak increases in coronary flow and the reduction in flow to the subendocardial portion of the infarcted area occurred at a heart rate of approximately 200/min provided by atrial pacing. Myocardial contractility, as evidenced by peak increases of 16% in maximum LV dP/dt and 12% in dP/dtP, was only enhanced with abrupt incremental changes in heart rate and not with continuous atrial pacing over 15-min periods. Despite the generalized increases in coronary perfusion coronary sinus oxygen content decreased with a widening of the coronary arteriovenous oxygen difference indicating increased myocardial oxygen usage. Thus increasing frequency of contraction in myocardial infarction results in a slight initial but not sustained inotropic effect, a moderate and generalized increase in regional myocardial blood flow, increased myocardial oxygen consumption, and the potential for subendocardial extension of the area of myocardial damage within the infarcted area.


Effects of drugs on the negative (backflow) component of velocity patterns in the dog aorta. Using an accurately calibrated flowmeter in the descending thoracic aorta of the dog, a study was made of alterations in aortic flow patterns following intravenous and intra-arterial injections of vasoactive drugs. When injected distal to the flowmeter, vasopressors caused marked backflow while vasodilators raised the level of the lowest portion of the pulsatile flow curve. When injected into the brachiocephalic artery, vasopressors prevented the development of a significant negative component whereas vasodilators caused the appearance of backflow, or augmented that which was already present. All acute elevations or decreases in peripheral resistance due to drugs were accompanied by increases in the negative or "backward" phase of flow in diastole. A significant negative flow component was noted only during these acute adjustments. A temporary differential in resistances of the upper and lower portions of the arterial circulation protected cerebral and coronary blood flow during acute haemodynamic adjustments.


Mathematical formulation of post-occlusion hyperaemia and autoregulation of blood flow in the capillaron model. A mathematical formulation of the blood flow behaviour through a capillaron model is described. The formulation is applied to the analysis of post-occlusion (reactive) hyperaemia and autoregulation.


A note on the phase-plane technique representation of cardiac action potentials. In this study the applicability of the phase-plane technique for interpreting membrane properties of cardiac cells in a two-dimensional structure is discussed. The conditions are derived for which the effects of two-dimensionality of a sheet can be neglected and for which the one-dimensional phase-plane technique for estimation of the membrane current densities remains valid. The usual phase-plane technique appears to be applicable to nodal and atrial tissue.


Electrophysiological effects of ajmaline in isolated cardiac tissue. The electrophysiological effects of increasing molar concentrations of ajmaline were studied in isolated cardiac tissue, including sino-atrial node and Purkinje fibre. Ajmaline produced significant shortening of the plateau of Purkinje fibre action potential associated with marked depression of dV/dt and directly measured conduction velocity. A negative chronotropic effect was noted both in the sinus node and in spontaneously beating Purkinje fibres. Ajmaline's major electrophysiological effect appears to be depression of Purkinje fibre conduction velocity.


Effects of practolol on exercise tolerance and cardiac haemodynamics and metabolism in patients with coronary artery disease. Sixteen male patients with typical angina pectoris secondary to coronary atherosclerosis performed two daily standardized exercise tests during two consecutive days. Three hours before each exercise they received placebo or 400 mg practolol administered orally in double-blind fashion in order to complete a cross-over design. Practolol significantly prolonged the exercise duration by 30.6% and delayed the appearance time of ischaemic electrocardiographic changes by 67.7%. Maximal heart rate, systolic pressure, and pressure-rate product were also reduced after medication. In order to investigate further the effects of this beta blocking agent, myocardial function and metabolism at rest and during supine exercise were assessed in 12 male patients with coronary artery disease before and after practolol 30 mg, iv. At rest, practolol produced a decrease in tension-time index (18%), cardiac index (17%), heart rate (10%), and stroke index (7%). A significant reduction was also observed in resting stroke work index (14%) and systolic and mean aortic pressure (6%). Left ventricular end-diastolic pressure remained unchanged. During supine exercise, only time-tension index (12%), heart rate (12%), and cardiac index (10%) were significantly reduced after the beta blocking agent. Practolol did not significantly change the arterial glucose, lactate, inorganic phosphate, potassium, calcium, magnesium, pH, PCO2, or PO2. The beta blocking agent did not modify the myocardial extraction of any of these substrates at rest or during exercise. In the dosage used in both studies, practolol significantly improved the exercise tolerance and reduced the ischaemic manifestations. The efficacy of practolol in angina pectoris may result mostly from its ability to decrease heart rate and systolic pressure during exercise.


Pulmonary valve incompetence. I. Evaluation using electromagnetic flow velocity catheters and a new valve insufficiency analyser. In animal experiments regurgitant flow through competent and incompetent pulmonary valves was evaluated with electromagnetic flow velocity catheters by using the ratio of the separately integrated backward and forward flow velocity signals. This ratio was obtained with a special purpose analog computing circuit set by an in-vitro zero flow reference signal, which was in good agreement with in-vivo zero flow signals.


Pulmonary valve incompetence. II. Application of electromagnetic flow velocity catheters in children. During cardiac catheterization in 49 children regurgitant flow through competent and incompetent pulmonary valves was evaluated with electromagnetic flow velocity catheters using the ratio of the separately integrated backward and forward flow velocity signals (vb/vf). When the pulmonary valve was normal, vb/vf was less than or equal to 0.10. After operation for pulmonary valve stenosis or tetralogy of Fallot larger values were often found. In patients with an outflow patch across the pulmonary valve ring vb/vf values of up to 0.54 were found.


The accuracy of caridac function indices derived from ultrasonic time-position scans. A study has been made of Time-Position ultrasonic scanning as a means of obtaining measurements related to cardiac performance. The errors involved in determining these measurements have been estimated. It has been shown that the greatest accuracy can be achieved for quantities which depend on action rather than shape, such as ejection fractions and rates of myocardial fibre shortening. Attention is drawn to the fact that the ultrasonic method, unlike angiography, in no way alters the quantities being measured.


Effects of intra-arterial ethanol in cardiogenic shock. Unanaesthetized mongrel dogs in cardiogenic shock received a 30-min intra-arterial infusion of 1 X 9 g/kg of 40% ethanol. Alcohol produced significant vasodilatation and improvements in the mean blood pressure and cardiac output. Arterial pH and the arteriovenous oxygen difference were markedly reduced, and the blood glucose concentration was significantly increased. Despite a considerable reduction in serum CPK levels, survival was not improved by ethanol.


Distribution of coronary collateral flow in acute myocardial ischaemic injury: effect of propranolol. The local distribution of coronary collateral flow was mapped using 8 mu tracer microspheres following circumflex coronary occlusions in dogs. Overall flow to the ischaemic posterior papillary muscle and subjacent myocardium decreased to 21% of anterior free wall flow. Collateral flow was non-uniform, however, and was lower in the subendocardium (14%) than in the subepicardium (27%). Brief temporary occlusions with and without propranolol therapy showed that collateral flow was less and the inner/outer wall ratio was unaltered in treated animals. Although propranolol reduces infarct size after coronary occlusions, this effect appears not to be related to increases in collateral flow.


Selective versus non-selective His bundle pacing. His bundle pacing was achieved in 10 anaesthetized open chest dogs by stimulation from bipolar electrode catheters positioned in the aortic root and right heart. Recordings were taken directly through plunge wires from the right atrium, high ventricular septum, and epicardial sites on the right and left ventricles. Six types of response were seen during A-V junctional stimulation: (1) low atrial pacing; (2) combined atrial and His bundle pacing; (3) His bundle pacing; (4) combined atrial, ventricular septal, and His bundle pacing; (5) combined septal and His bundle pacing; and (6) ventricular pacing. Pacing of the His bundle in combination with the atrium and/or ventricular septum is designated as non-selective, whereas stimulation of the His bundle alone is considered selective pacing. Non-selective His bundle pacing can be recognized from the surface leads by changes in onset and amplitude of the QRS with appreciable T-wave alterations. Although electrode position was an important determinant of the type of pacing achieved, a variety of patterns of stimulation resulted from variation in the modalities of the pacing stimulus, ie, polarity, intensity, and duration. Unless these factors are considered, selective His bundle pacing may not be achieved.


Scanning electron microscopy of the glomerular filtration membrane in the rat kidney. The rat kidney was perfused with saline and glutaraldehyde, treated with Murakami's tannin-osmium impregnation method, ethanol-freeze cracked and dried by the critical point method. Gold-palladium evaporated specimens were observed in a field-emission scanning electron microscope. The glomerular filtration membrane, fractured in different planes was observed with the following results: 1. Adjacent pedicles originate from different podocytes. No interpedicular bridges of apparent cytoplasmic nature could be found. 2. The basement membrane, in grazing fractures shows a horizontally layered architecture. 3. The attenuated endothelial sheet (lamina fenestrata) is divided into compartments, which we suggest should be called "areolae fenestratae", by cytoplasmic crests radiating from the nucleated portion of the endothelial cell. A crest also occurs along the cell margin, which contacts a similar crest at the margin of the adjacent cell. 4. The pores in the areolae fenestratae are variable in size (30-150 nm diameter). A knob-like projection from the apparently naked basement membrane is found in a portion of the pores. 5. Numerous microvilli may occur on the endothelium. Some of them anastomose and fuse with one another to form a net whose meshes appear identical with the endothelial pores. Domes and shelves formed of a fenestrated cytoplasmic sheet also occur above the ordinary level of the endothelial lining. A hypothesis implicating microvilli in the partial renewal of the endothelial sheet is proposed.


Relationship between ciliary rootlets and smooth endoplasmic reticulum. In ciliated cells of thymic cysts in Nude mice, ciliary rootlets are constantly and closely related to smooth endoplasmic reticulum and clear vesicles. This special association suggests that this structure does not play only an anchoring role but must be involved in the general metabolism of the cilium.


The housefly interfacetal hair: ultrastructure of a presumed mechanoreceptor. The external and internal fine structure of the housefly interfacetal hair and its sensory dendrite was studied with the scanning and transmission (high and low voltage) electron microscopes. The hair shaft contains no dendrites, and is usually situated within a socket on the lens surface. Immediately beneath and directly connected to the base of each hair is a bipolar neuron whose dendrite tip is enveloped in a shealth cell which, in turn, is surrounded by a second sheath cell. Septate junctions are seen between all these cells and contiguous portions of a large pigment cell. At the hair base, the dendrite of the neuron terminates in a tubular body only 1.5 mum in diameter which is filled with about 400 microtubules in highly ordered (in parallel pentagonal and hexagonal) arrays and whose sides are fused to neurofilaments in parallel. Another filament (ca. 70 A diameter) is in the center of each microtubule-neurofilament polygon. Structures proximal to the tubular body are typical for a scolopoid sensillum, i.e., connecting cilium (9 times 2 + 0 microtubules) with rootlet and basal bodies, unmodified dendrite, perikaryon and axon. The axon has not been traced to its synapse. The high degree of internal organization and shortness of the tubular body, as well as its eccentric insertion into the hair shaft lead to the hypothesis that this hair may be a highly sensitive mechanoreceptor. On the basis of their single innervation, these hairs could monitor flight speed from the degree of hair deflection caused by wind in general or particular laminar air currents flowing past the eyes during flight.


Correlation between suckling-induced changes in the ultrastructure of mammotrophs and prolactin release. Effects of suckling on the structure of mammotrophs and the release of prolactin, were studied in rats on the 10th day of lactation with the use of electron microscopy and radioimmunoassay techniques. Nursing animals were separated from their young for 8 hr and subsequently united and permitted to nurse for 1, 5, 15, 30 min; or 1, 2 and 4 hr. Blood samples were obtained prior to and throughout the suckling interval and pituitary glands were processed for electron microscopy. Control animals consisted of normal lactating females and animals separated from their young for 8 hr. Normally lactating controls had high prolactin serum levels (501 +/- 95 ng/ml) and synthetically active appearing mammotrophs. An 8 hr separation from the pups induced a dramatic lowering of serum prolactin (32 +/- 5 ng/ml), an increase in secretory granule storage, and a great dilation of rough endoplasmic reticulum (RER) cisternae. Five min of renewed suckling resulted in a rise of plasma prolactin levels (605 +/- 183 ng/ml) which remained high thereafter. The major ultrastructural changes observed during the first 30 min of suckling were as follows: 1) at 1 min, the RER became cmone?); 2) AT 5 MIN, AND MUCH MORE OBVIOUSLY AT 15 AND 30 MIn, a massive discharge of secretory granules was observed; and 3) at 15 min, the collapsed RER underwent transformation for 1,2 and 4 hr) induced new hormone synthesis as suggested by the presence of hypertrophied Golgi elements and numerous immature granules. This was accompanied by a new transformation of the RER from the vesicular into a lamellar form now consisting of very slender cisternae lined with numerous ribosomes, presumably involved in the renewal of the synthetic process. The morphologic findings described correlate well with the time table of prolactin release. In addition, the dramatic early changes in the structure of the RER suggest a possible involvement of this organelle in the storage and release of a proposed rapidly releasable pool of prolactin.


An ultrastructural examination of the action of vinblastine on microtubules, neurofilaments and muscle filaments in vitro. In vitro incubation of autonomic nerves with vinblastine sulphate (1 times 10(-4) M) caused a disappearance of microtubules within 15 min; during the following 15 min paracrystalline arrays appeared within the axons. An increase in the abundance of microfilaments was also observed, but these did not appear to arise from disaggregated microtubules since the increase in microfilament numbers was noted at an incubation time when crystal formation was extensive. Pretreatment of autonomic nerves with colchicine (2.5 times 10(-4) M) caused a reduction of approximately 80% in the numbers of microtubules, but did not prevent the formation of crystals on subsequent exposure to vinblastine. No ultrastru"tural changes were observed in myofilaments on incubation with vinblastine.


Fine structure of the fetal rat thyroid and parathyroid glands at term and during prolonged gestation. The fine structure of the fetal rat thyroid and parathyroid glands was studied at term and during prolonged gestation, which was induced by subcutaneous injections of progesterone to the mothers from gestational days 20 through 24. At term, the follicular and parafollicular cells of the thyroid as well as cells of the parathyroid exhibited well developed cytoplasmic organelles. Morphological changes were not detected in either of the endocrine glands during prolonged gestation. The results are discussed in relationship to 1) thyroid follicular cell activity during stress and 2) the function of thyroid parafollicular and parathyroid cells in calcium homeostasis.


Cytoplasmic actomyosin fibrils in tissue culture cells: direct proof of contractility by visualization of ATP-induced contraction in fibrils isolated by laser micro-beam dissection. A special cell line derived from a rat mammary adenocarcinoma (RMCD cells) displays a distinct pattern of actomyosin fibrils (AM fibrils) visible with phase contrast, Nomarski interference and polarized light optics. It was shown that the cytoplasmic AM fibrils are arranged as bundles of highly parallel F-actin filaments. The chimical nature of the filaments was identified by incubation with heavy meromyosin from rabbit skeletal muscle. These cytoplasmic actomyosin fibrils actively contract under isotonic conditions. This was shown by contraction experiments under polarized light optics, by cinematographic analysis and by direct proof of the contractility of AM fibrils isolated by laser micro-dissection. Thus, cytoplasmic AM fibrils can be assumed to represent structures essential for motive force generation in contraction processes in non-muscle cells.


Synaptoid profiles in regenerating crustacean peripheral nerves. Synapse-like structures occurring in regenerating crayfish peripheral nerves are characterized by aggregates of small (250 to 600 A) electron lucent vesicles adjacent to a thickened "presynaptic" membrane. Such synaptoid profiles are seen opposite other axons, glial processes or extracellular fibrous material. Junctions with cellular elements do not show "postsynaptic" specializations. These complexes are compared to axo-glial synapses in the developing spinal cord and to synaptoid configurations observed by others in vertebrate and invertebrate neurosecretory systems.


Localization of dopamine in the endocrine hypothalamus of the rat. Microspectrofluorometry, fluorescence histochemistry and light and electron microscopic autoradiography have established the presence of sub-populations of neurons in the arcuate-periventricular region of the rat hypothalamus that sequester both radiolabeled dopamine and demonstrate formaldehyde-induced fluorescence. These characteristics are consistent with a catecholaminergic function. Selective sequestration of 3H-dopamine at the light and ultrastructural level is discussed in the context of an ultrashort loop autoregulatory mechanism for this neuronal population.


Neurosecretory cell types in the eyestalk of the freshwater prawn Palaemon paucidens: an electron microscopic study. In the medulla terminalis ganglionic X-organ (MTGX) of the eyestalk of the freshwater prawn, Palaemon paucidens, six peptidergic neurosecretory cell types (A-, B-, C-, D-, E-, and F-cells) are distinguishable on the basis of the different morphology of their elementary granules and rough endoplasmic reticulum (rER). All of these cell types seem to correspond to Type-IIIa cells or dispersing Type-IV cells, that have previously been differentiated at the light microscopic level (Hisano, 1974), as judged from the dimensions of their cell bodies and nuclei. Two other peptidergic neurosecretory cell types that are apparently comparable to the Type-II and Type-IIIb cells (Hisano, 1974), respectively, are recognized in parts of the optic ganglia other than MTGX, and these are now designated as G- and H-cells, respectively. All the remaining cell types, designated as Type-I, cluster-forming Type-IV, Type-V and Type-VI cells in our previous light microscopic study, have small cored-vesicles in their cytoplasm. It remains undecided whether these, possibly aminergic, neurons are neurosecretory or not.


The lateral recess of the third ventricle in teleosts: an electron microscopic and Golgi study. The ependyma lining the lateral recess of the third ventricle of the teleost inferior lobe has been studied by light and electron microscopy, including Golgi impregnation methods. As many as five different cell types appear to line the ventricle, but some of these may be similar cells in different stages of activity. One cell type contains small dense-cored vesicles and appears to have processes extending into deeper portions of the lobe. Golgi preparations reveal subependymal cells with apical processes extending to the ventricle and basal extensions which may reach the pial surface. The present observations are discussed in relation to similar studies in other fishes, amphibians and mammals. Possible functions for the various cells observed are suggested.


A structural study of the anal papillae of the midge Chironomus riparius Meigen (Diptera: Chironomidae). Larvae of the midge, Chironomus riparius Mg., have four anal papillae arranged as two pairs, one dorsal to and the other ventral to the anus. Structural study with light and electron microscopes has revealed that their integument consists of a thin cuticle overlaying a thick, syncytial epidermis which is specialised to facilitate ion transport. There is a distinct neck or collar region at the junction of each papilla with the rest of the body wall. Although in many respects these structures resemble those in mosquitoes, there are both morphological and physiological features which suggest that differences exist in the means by which ion exchange with the environment is controlled and effected in the two families.


Fat and glycogen utilization in the larynx Muscles of fire-bellied toads (Bombina bombina L.) during calling activity. Both fat and glycogen are present in abundance in the larynx muscles of anurans. To clarify their role, the Musculus dilatator laryngis of the male fire-bellied toad, Bombina bombina was studied. In untreated males, the mean fat content of this larynx muscle was 14%; the muscle contained glycogen amounting to 57% of that measured in the liver tissue of the same animal. After thirteen days of continual calling activity induced by administration of a gonadotropin, the fat content fell to 6%, the glycogen to 34%. The fat content was essentially unchanged (13%) by four hours of electrical stimulation of the muscle; the glycogen content, however, had fallen to 42% after this treatment. Neither component was altered in amount by castration, the fat content being about 13% and that of glycogen, 52%. Nor did treatment with gonadotropic hormone reduce either the fat content (13%) or the amount of glycogen (59%). From these results it was concluded that fats represent a direct source of energy for the larynx muscles, which is used up gradually over long periods of calling. The glycogen in these muscles, on the other hand, is a short-term store sufficient to supply energy for only a few hours of calling activity.


The saccus vasculosus of Anguilla anguilla (L.) from larva to adult. I. Ultrastructural modifications of the coronet cells. The ultrastructure of coronet cells of the saccus vasculosus has been studied in specimens of Anguilla anguilla (L.) at different stages of its life cycle. At all the stages observed coronet cells are composed of a basal and an apical part, the latter bearing globules with primary vesicles. In the larva (a marine form) and in the fully metamorphosed small eel at the time of entry into freshwater the narrow lumen and the vesicles within the apical globules are filled with electron-dense material. In forms in which adaptation to freshwater has occurred, the saccus lumen appears expanded, the apical globules are better developed, and the electron-dense material has disappeared. It is suggested that the two situations observed represent different functional states of the organ, in relation to different conditions of environmental salinity.


Pituicytes in normal and Jimpy Mice.

Pituicytes in normal and Jimpy Mice. Neural lobes of control and "Jimpy" mice were examined electron microscopically. The ultrastructure and incidence of pituicytes was examined following reports of reductions in astrocyte and oligodendrocyte populations in areas of the CNS of Jimpy mice. The failure to demonstrate any modification of structure or numbers of the pituicytes in the affected animals suggests that the pituicytes are not as closely related to the satellite cells of the CNS as has previously been proposed.


Fate of 3H-thymidine labelled myogenic cells in regeneration of muscle isografts. Intact and denervated extensor digitorum longus (EDL) muscles of 20-day-old inbred Lewis-Wistar rats were labelled with 3H-thymidine. Ninety minutes after the injection of the isotope 4.0% of the nuclei were labelled in the intact (i.e. innervated) and 9.6% in the muscles, denervated 3 days before administration of the isotope. The labelled EDL muscles were grafted into the bed of the previously removed EDL muscles of inbred animals and these isografts were studied 30 days later. In the EDL muscles, regenerated from innervated isografts only occasionally labelled endothelial cells were found whereas in the muscles regenerated from denervated isografts also parenchymal muscle nuclei were regularly labelled. The incidence of labelled nuclei in the regenerated EDL muscles was, however, about 20 times lower than in the donor EDL muscles. The presen experiments provide a direct proof of utilization of donor satelite cell nuclei for regeneration in grafted muscle tissue. With respect to the low incidence of labelled nuclei in regenerated EDL muscles, other sources of cells apparently also contribute to the regeneration process.


Ultrastructure of the endocrine cell types in the adenohypophysis of the teleost, Poecilial latipinna--a morphometric model. A morphometric model providing detailed quantitative information on the ultrastructure of the adenohypophysial endocrine cells has been developed for Poecilia latipinna. The model consists of various morphological components quantified in terms of volumes, surfaces or numbers. For prolactin and growth hormone cells, appropriate results are expressed relative to the average volume of that cell type. The difficulties of quantifying EM data on pituitary glands, together with the various sources of error to which the data are clearly open, have been discussed. Some practical application of quantitative EM to problems in fish pituitary research are outlined.


Oogenesis in the malaria Mosquito Anopheles gambiae. Oogenesis has been followed with the electron microscope in 2 strains of the malaria mosquito Anopheles gambiae, from the emergence of the adult (oocytes at leptonema) till shortly before the oocytes are ready for oviposition. After pachynema the chromosomes form a karyosphere and a fibrous capsule develops around it. Work on other mosquitoes suggests that the capsule may be related to the synaptonemal complexes. Bot Anopheles strains contain at some time an extrachromosomal (not DNA-containing) body comparable to the karyosphere in size. Clusters of granules are present at the surface of the nucleolus and free in the nucleoplasm. Tentative results indicate that they may contain DNA. During oogenesis the nucleolus becomes very large, mainly because of proliferation of the nucleolonema. Towards the end of oocyte development of the nucleus assumes the large canoe-shape also seen in Aedes and Culex. Nucleolonema traverse the entire nucleus, and modified granular clusters are found throughout.


The ultrastructure and calcification of the scales of Tilapia mossambica (Peters). The scales of Tilapia are surrounded by an envelope of scleroblasts responsible for the production of layers of collagen that constitute the bulk of the scale. The scleroblasts adjoining the lateral face of the oldest scale region gradually atrophy. New Collagen layers are deposited against the inner face of the scale, the adjoining scleroblasts showing evidence of high metabolic activity. Calcification occurs by inotropic deposition of crystals alongside the fibres. There is no sharp demarcation between calcified and non-calcified scale regions, a calcification front gradually moving towards newly formed collagen layers. It is felt that fish scales should be considered as calcified derivatives of dermal collagen layers.


Histological and electron microscopical observations on the effects of different salinities and heavy metal ions, on the gills of Jaera nordmanni (Rathke) (Crustacea, Isopoda). The effects of different salinities and concentrations of copper, mercury and cadmium ions on the gills of Jaera nordmanni are investigated by means of light and electron microscopy. After exposure to 10% and 50% sea water the gill epithelium cells show a marked uniformity in appearance, possessing characteristically large, sub-cuticular spaces which are prominent between microvilli. With exposure to the heavy metal ions a similar sequence of histological and ultrastructural changes occur in all the gill epithelial cells, culminating in cell breakdown. The ultrastructural changes include distended microvilli, dilated endoplasmic reticulum, dissociated ribosomes, diffuse (swollen) cytoplasm, swollen mitochondria and a basal membrane withdrawn from the basal lamina. An increase in the number of haemocytes is also commonly observed in the haemolymph spaces during heavy metal ion exposure. The significance of the morphological changes undergone by the gill epithelial cells after exposure to different salinities and heavy metal ion concentration, are discussed in relation to the physiological functioning of the gill.