Stable alterations at the cell membrane of Chinese hamster ovary cells resistant to the cytotoxicity of phytohemagglutinin. Chinese hamster ovary (CHO) cells selected for resistance to the cytotoxicity of phytohemagglutin (PHA) have been found to exhibit stable alterations at their plasma membranes. The PHA-resistant (PhaR) cells bind markedly less 125I-PHA than do sensitive CHO cells and also exhibit an increased sensitivity to the cytotoxicity of concanavalin A, a lectin of different receptor specificity. Mutagenesis with ethylmethanesulfonate increases the proportion of PhaR cells 20- to 100-fold. PHA-resistant cells maintained for up to 8 months in continuous culture in the absence of the selective agent have retained the PhaR phenotype. These and other characteristics of the experimental system suggest that CHO cells selected for PHA resistance are authentic somatic cell mutants. The Pha marker appears to behave recessively in hybrids formed between PhaR and PhaS cells.


Human intraspecific somatic cell hybrids: a genetic and karyotypic analysis of crosses between lymphocytes and D98/AH-2. A number of human intraspecific hybrids were produced by fusing the 8-azaguanine-resistant cell line D98/AH-2 with PHA-stimulated lymphocytes from a normal human male, followed by selection in HAT medium. The parent cells differed in zymogram patterns for 4 enzyme systems. Hypoxanthine-guanine phophoribosyltransferase was missing in D98/AH-2 and was determined in the hybrids by the normal gene derived from the lymphocyte donor's X chromosome. The HL-A antigens of the lymphocyte donor as well as the W28 specificity from HeLa were easily recognized by a cytotoxicity assay on the hybrid cells, while D98/AH-2 itself was not killed in the normal way by any HL-4 typing sera. The initial hybrid karyotype in all lines was relatively stable, but slow loss of chromosomes occurred following extended growth in culture. The importance of the culture conditions for the rate of chromosome loss was demonstrated. The behavior of several chromosomes was followed in the hybrids and their derivatives. There was relatively nonspecific loss of small numbers of chromosomes, showing that loss of chromosomes from both the D98/AH-2 and the normal lymphocyte parent can occur. Cell lines resistant to 6-thioguanine were selected from the sensitive hybrids. Most had lost the lymphocyte donor's X chromosome, thereby losing the only active allele for HGPRT present in the initial hybrids. However, one line, DMR41, apparently retained the X chromosome and may have a mutated allele for HGPRT. Two lines that are the products of spontaneous segregation are also described. DM4CS  and DM17A.


A human-mouse somatic hybrid line selected for human deoxycytidine deaminase. A new selective medium has been developed for cells containing the enzyme deoxycytidine deaminase. This medium contains hypoxanthine, aminopterin, and 5-methyldeoxycytidine (HAM medium). To survive in the presence of the aminopterin, the cells must utilize deoxycytidine deaminase to convert the 5-methyldeoxycytidine to thymidine. The cells must also have thymidine kinase and hypoxanthine phosphoribosyltransferase. A mouse cell line deficient in deoxycytidine deaminase has been isolated from a deoxycytidine kinase-deficient line, using 5-bromodeoxycytidine as the selective agent. A hybrid line between this double mutant and a human diploid fibroblast was isolated in HAM medium. The hybrid line contains the chromosomes expected of a human-mouse hybrid. The deoxycytidine deaminase isozyme patterns on cellogel show that the human-mouse hybrid cell line produces an enzyme with an electrophoretic mobility intermediate between that of the human and that of the mouse.


Biochemical genetics of Chinese hamster cell mutants with deviant purine metabolism: biochemical analysis of eight mutants. Purine biosynthesis was studied in 8 mutants of Chinese hamster cells which require purines for growth and in wild-type cells which do not show this nutritional requirement. Of these, 6 mutants, ade-B, ade-D, ade-E, ade-F, GAT-, and AT-, were shown to accumulate metabolic intermediates not accumulated by wild-type cells. These intermediates were shown to be compounds unique to the adenylic acid biosynthetic pathway by the following criteria: (a) their radioisotopic labeling properties, (b) their response to agents which specifically inhibit known enzymatic steps in the pathway, (c) their chromatographic properties, and (d) spectrophotometric analysis. Two mutants, ade-A and ade-C, accumulate no detectable compounds not accumulated by the wild type. These 2 mutants are believed to be defective in steps very early in the purine biosynthetic pathway. The sites of the defects in the other mutants are proposed, and the usefulness of these mutants is discussed.


Cell-mediated immunoselection against cell-surface antigens of somatic cell hybrids. Cytotoxic lymphoid cells derived from in vivo immunization of mice across H2 barriers were utilized in in vitro cytotoxicity assays. The target cells were somatic cell hybrids derived from parental cells differing at the H2 locus. The hybrid cells surviving cytotoxicity were grown to confluent populations and the H2 antigens selected against were no longer demonstrable by indirect immunofluorescence. Comparative karyology of hybrid cells expressing both parental H2 types before immunoselection with hybrid cells surviving immunoselection revealed a decrease in the number of murine chromosomes number 17, suggesting that those cells surviving cytotoxicity had spontaneously lost these chromosomes prior to the selection event. The possibility of immunoconstruction of somatic cell hybrids on the basis of their cell-surface antigens is discussed.


Incorporation of isolated chromosomes and induction of hypoxanthine phosphoribosyltransferase in Chinese hamster cells. Evidence is presented for the uptake of radioactive-labeled isolated Chinese hamster chromosomes following incubation with Chinese hamster cells. Metaphases were found which contained radioactive labeled chromosomes in a very low frequency, and in some of the labeled chromosomes only one chromatid was labeled. Incubation of hypoxanthine phosphoribosyltransferas (HPRT)-deficient Chinese hamster cells with chromosomes isolated from HPRT+ Chinese hamster or human cells resulted in the appearance of HPRT+ cells. Clones derived from these cells were isolated in HAT medium. Cells in mitosis during incubation with the chromosomes yielded thr-e times more HPRT+ clones than did cells in interphase. The intraspecies combination involving recipient cells and chromosomes from Chinese hamster origin yielded significantly higher numbers of HPRT+ clones than did the interspecies system using human chromsomes and Chinese hamster recipient cells (5 X 10(-5) and 6 X 10(-6) respectively). Electrophoresis of HPRT from Chinese hamster cells treated with human chromosomes revealed the pattern of the human enzyme.


Globin synthesis in fibroblasts fused with erythroblasts. I. Avian fibroblasts. Heterokaryons of chick embryo erythroblasts fused with other avian fibroblasts were studied with regard to globin production. After the incorporation of radioactive amino acids, soluble proteins were separated on SDS-urea polyacrylamide gels. There was a striking increase in radioactivity above background in the globin region from lysates of fusion cultures when compared with fibroblast cultures. This was maximal at 24 hours after fusion, and then declined. Electrophoresis on acid-or alkaline-urea gels further identified the material as globin chains. Tryptic digestion and fingerprinting revealed methionine-labeled peptides characteristic of chick embryo erythroblast globin. An apparent stimulation of globin chain synthesis by heterokaryons compared to erythroblasts was found to be due to a difference in the specific activity of the precursor amino acid pools in the different cell types.


Selection by [3H] amino acids of CHO-cell mutants with altered leucyl- and asparagyl-transfer RNA synthetases. Efficient selection procedures, using [3H]amino acids as the selecting agent, were developed for isolating temperature-sensitive (TS) mutations in CHO cells affecting protein synthesis. After chemical mutagenesis, leucyl-tRNA synthetase mutants were obtained when [3H]leucine was used as the selecting agent in two independent experiments. These mutations seem to involve the same genetic locus as the TSH1 mutant described previously (1). A selection with [3H]valine, in which all amino acids except leucine were at low concentration in the selective medium, resulted in a new class of mutants with reduced asparagyl-tRNA synthetase activity. These results were consistent with the finding that all mutants were phenotypically dependent on the concentration of amino acid, specific to the altered synthetase, in the medium. Our observations suggest that although leucyl synthetase mutations are a relatively common class of TS mutations in CHO cells, the spectrum of mutants obtained can be at least partially manipulated through concentrations of amino acids in selective media. The asparagyl-synthetase mutation was shown to be recessive and to complement the leucyl-synthetase mutation in cell-cell hybrids.


Interaction of male and female germ cells of two mammalian species in culture. When viewed by scanning electron microscopy, the heads of mouse spermatozoa are smaller than those of the hamster. The vitelline microvilli of hamster eggs are longer than those of the mouse egg. Both these factors may contribute to the enhanced interaction of mouse spermatozoa and hamster eggs. Treating unfertilized mouse eggs with Newcastle disease virus causes the viteline microvilli to elongate, thus improving the interaction between mouse eggs and hamster spermatozoa.


Genetics of somatic cell surface antigens. III. Further analysis of the AL marker. The AL antigen present on the surface of various human somatic cells, and on those hybrids of human and Chinese hamster ovary cells which have retained human chromosome number 11, has been resolved into at least two separate antigenic activities, a1 and a2. Specific antisera active against each antigen separately have been prepared. By treatment of the original AL+ hybrid with mutagenic agents and selection in particular antisera, stable clones are preparable whose phenotypic behavior corresponds to the antigenic compositions a1+ a2-, a1- a2+, and a1- a2-. The adsorption behavior of these variants for specific antisera is consistent with  their phenotypic assignments.


Human RNA transcripts in man-mouse somatic cell hybrids. II. Thermal denaturation studies and Cot analysis. The present report confirms an earlier finding that human RNA transcripts from a man-mouse somatic cell hybrid that has regularly retained only the human X chromosome can be identified by molecular hybridization on nitrocellulose filters. From thermal denaturation studies it is concluded that molecular hybrids between hybrid cell and human nucleic acids have higher Tm's, and thus greater specificity, than those between mouse and human nucleic acids. Additional data, utilizing the kinetics of molecular hybridization in solution (Cot analysis), demonstrate the presence of "few gene copy" DNA sequences in the above-mentioned hybrid cells that are complementary to human (HeLa) HnRNA. Also shown is a fraction of hybrid cell HnRNA that is complementary to "few gene copy" DNA sequences of human DNA. Thus, the experiments reported may represent a specific assay for identifying reiterated and "few gene copy" DNA sequences of the human X chromosome and their complementary RNA. Theoretically this experimental approach may be extended to any chromosome. Some of the short-term and long-term perspectives of these types of studies are discussed.


Synteny between the pro+ marker and human glutamate oxaloacetate transaminase. Chinese hamster ovary cells with a specific auxotrophy for proline were fused with human cells from a variety of sources and the resulting hybrids analyzed for human genetic markers. Of 63 hybrid clones examined, 27 possessed both proline and cytoplasmic glutamate oxaloacetate transaminase markers; 36 had neither; and no clones were found possessing one and not the other. These results constitute evidence that the proline and glutamate oxalocetate transaminase markers are syntenic. Evidence for absence of synteny between these and a variety of other human genes is presented. Biochemical tracer experiments established that the proline biosynthetic pathway through glutamate has been restored in the Pro+ hybrids.


Chinese hamster X mouse hybrid cells segregating mouse chromosomes and isozymes. Hybrid cells are readily formed by fusing clonal Chinese hamster cells to fresh, noncultured, adult mouse spleen cells followed by isolation in selective medium. The vast majority of such hybrids retain Chinese hamster chromosomes and isozymes while segregating mouse chromosomes and isozymes. The growth, plating efficiency, ease of karyology, and rapid segregation of mouse markers allows linkage tests in primary clones. Analysis of 13 isozymes showed 12 to be asyntenic and on epair (PGD-PGM2) to be syntenic This system will allow extensive somatic cell hybrid gene mapping in the mouse and permit a comparison of human and mouse linkage relationships.


Gene linkage analysis in the mouse by somatic cell hybridization: assignment of adenine phosphoribosyltransferase to chromosome 8 and alpha-galactosidase to the X chromosome. Somatic cell hybridization techniques were applied to gene linkage analysis in the laboratory mouse. Cells of an established line of Chinese hamster lung fibroblasts were fused with mouse embryo fibroblasts and with mouse peritoneal macrophages obtained from different inbred strains. From 3 hybridization experiments, 123 primary and secondary clones were isolated in HAT selective medium and 24 were back-selected in 8-azaguanine. Hybrid clones were characterized for the expression of 16 murine isozymes by starch, acrylamide, and Cellogel electrophoresis, and on the basis of segregation data, 3 syntenic associations could be made. Malate oxidoreductase decarboxylating (MOD) and mannose phosphate isomerase (MPI) segregated concordantly, confirming an established linkage relationship; adenine phosphoribosyltransferase (APRT) segregated concordantly with glutathione reductase (GR) which is known to be on chromosome 8; alpha-galactosidase was observed to be syntenic with hypoxanthine phosphoribosyltransferase (HPRT), and X-linked enzyme. All other isozymes examined segregated independently of one another.


The dose-response relationship for ultraviolet-light-induced mutations at the hypoxanthine-guanine phosphoribosyltransferase locus in Chinese hamster ovary cells. Exposure of Chinese hamster ovary (CHO) cells clone K1BH4 to ultraviolet (UV) light at doses up to 86 ergs/mm2 did not significantly reduce cell survival, but UV doses of 86-648 ergs/mm2 produced an exponential cell killing. Observed mutation frequency ro 6-thioguannine resistance induced by UV increases approximately in proportion to increasing doses up to 260 ergs/mm2 in a range of 5-648 ergs/mm2 examined. The pooled data of mutation frequency f(X) as a function of dose X from 0-260 ergs/mm2 is adequately described by f(X)=10(-6) (13.6 + 2.04 X). That the UV-induced mutations to 6-thioguanine resistance affects the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus is supported by the observation that all randomly isolated drug-resistant colonies contained highly reduced or undetectable HGPRT activity.


Abnormal umbilical vessels and systemic circulatory reversal in thoracopagus twins. A human thoracopagus of slightly unequal twins having a common umbilical cord with exomphalos is described with special reference to the cardiovascular system. The larger twin had single umbilical artery. The smaller twin had a large left umbilical artery which was in direct continuity with the aorta, a small right umbilical artery with sole connection to the right external and internal iliac arteries (right common iliac artery was absent), missing umbilical vein, a rudimentary nonfunctional heart with  atresia of the truncus arteriosus, and a right-sided aortic arch. Exomphalos of both twins is accounted by the possible defective growth of umbilical mesoderm caused by abnormal umbilical vessels. Reversal of sustemic circulation in the upper part of the body of small twin is discussed. The importance of a careful study of umbilical veins is emphasized.


[Clastogenic effect of trenimon on in vitro chromosomes of phemotypically healthy subjects with morphologically abnormal caryotype]. The effect of a given concentration of Trenimon (6 xpe was analysed in vitro. The research included 6 subjects with balanced translocations, one of them with a centric fusion. Of the remaining 5 subjects, 2 had a duplication in the paracentric region, 1 showed an inversion, and 2 had a marker chromosome. In the group with morphologically abnormal chromosomes a higher sensibility to the influence of Trenimon was found as compared with a control group with morphologically normal karyotype. The subjects with an atypical karyotype had 36 to 65% aberrations, the control group 28%. A localization of the breaks showed no increased aberration rates in the morphologically abnormal chromosomes.


Dermatoglyphic studies in patients with Cooley's anemia and Cooley's trait. The dermatoglyphic analysis of a group of Italiam patients with Cooley's anemia and Cooley's trait shows Cooley's anemia patients to undergo a significant increase of loops on fingers and a corresponding decrease of whorls. The total loops frequency correlates negatively with the ridge distribution per loop and the total ridge count is significantly decreased. The atd angles are larger. Minor changes in the distribution of patterns in the thenar and hypothenar areas are also observed. In the Cooley's trait patients, loops on fingers are more frequent than in controls, but no difference with Cooley's anemia series is observed. The above findings suggest that the gene(s) controlling loops formation in linkage disequilibrium with thalassemia mutant may have been favourably selected on the "thalassemia chromosome" in the malaria environment.


[Genetic counseling in congenital deafness]. The risk of having a child affected by isolated congenital deafness (or deafmutism) is high, if the two parents are affected, if only one parent is affected, but belonging to an affected family, and if the couple has already an affected child.


Interactive system for automatic analysis of human R-banded metaphases. A computer system analysing human metaphase images and finding banding patterns of R-banded chromosomes has been set up. This first paper describes the interactive procedure in selection of metaphase images, automatically digitized starting from microphotographic negatives.


Trisomy 2q.

Trisomy 2q. Two unrelated patients with trisomy 2q32 leads to q37, resulting from maternal balanced translocations t(2; 13) (q32 q33) and t(2; 15) (q32 q26) are reported. Conparison of the clinical findings suggests that trisomy 2q is associated with a rather characteristic constellation of symptoms and malformations.


A case of "g 2 deletion syndrome": ring or partial monosomy? (46,XX,22r or 46,XX,22p- ?). A case of "G2 Deletion Syndrome" is reported, based on concordant cytogenetic, clinical and dermatoglyphic findings. The definition if the syndrome, as associated with either a ring or a partially deleted chromosome 22, is discussed. The resulting interpretation favours the hypotheses of deletion of the short arm extending into the centromere.


Inheritance of a peculiar type of hypodonitia. A peculiar type of hypodontia is described in two opposite sexed siblings and considered to be inherited as an autosomal recessive trait.


Distribution of  Gm and Inv factors in two samples of the Greek population. Gm and Inv polymorphism has been investigated on a sample of the general Greek population (N = 256) and on a sample of the Achaia population of Northwestern Peloponnusus (N = 150). The estimated frequencies were, respectively in the two groups: Gm1, 0.156 vs. 0.180; Gm1,2,0.010 vs. 0.017; Gm4,12, 0.834 vs. 0.803; Inv (+1), 0.125 vs. 0.140.


The Gm and Inv factors in rheumatoid arthritis. The Gm(1), Gm(2), Gm(4), Gm(12), and Inv (1) factors were studied in the sera of 56 patients suffering from rheumatiod arthritis and 26 from various rheumatic diseases, by the hemagglutination inhibition test, using optimally reacting mixtures of Ragg and Nagg sera. The distribution of these factors was found to agree with that of healthy Greeks. No correlation was found between hypergammaglobulinemia and the discovery of the Gm(1) and Inv (1) factors. The presence of the rheumatoid factor was independent of the Gm and Inv phenotypes.


The red cell acid phosphatase polymorphism in Greek b-thalassemia patients. Red cell acid phosphatase polymorphism was studied by starch gel electrophoresis in 70 b-thalassemia patients and in 310 healthy Greeks. Our results gave the following gene frequencies; b-thalassemia patients: pa 0.321, pb 0.643, pc 0.036; healthy Greeks: pa 0.302, p b 0.653, pc 0.045. No statistically significant differences were found between the two groups.


Mid-phalangeal hair, hand clasping and handedness among Khatris and Baniyas of Patiala, India. Mid-phalangeal hair, hand clasping and handedness have been examined in 425 adult subjects from two endogamous groups of Patiala, Hindu Khatris (230) and Baniyas (195). In a majority of subjects (53.73% in males and 46.35% in females) mid-phalangeal hair appears to be completely absent. The highest frequency of this trait is found in the combination III-IV and, when considering individual digits, on IV (around 50%). As for hand clasping, R-type appears to be more frequent in Khatris and L-type in Baniyas. Right handedness appears to be by large more frequent in both groups and sexes.


Effect of the immunizing dose of soluble and immobilized immunglobulins on the production of antibodies. The role of the immunizing dose on antibody production was studied in rabbits. The humoral immune response to soluble and insoluble human IgG was evaluated by the measurement of the amount of specific antibodies. The immobilizations of antigen was made by antigen-antibody precipitation and attachment of the protein to polyacrylamide and agarose matrices. It was found, that the antibody production did not decrease when the antigen dose was reduced from 100 microng to 300 microng; application of the antigen in immobilized form did not enhance the antibody response.


Behaviour of polyclonal human IgE in the course of fractionation. Normal human pooled plasma was fractionated by a variety of methods. The IgE concentration of the different fractions was determined by a solid-phase radioimmunoassay. The results of these studies indicate, that polyclonal IgE behaves similarly to IgE of myeloma origin. A biospecific method was worked out to purify IgE from fraction III of the cold ethanol fractionation procedure.


Improved method for isolation of human IgM as a by-product. The authors describe a simple method for isolating heterogeneous IgM from fraction I obtained as a by-product of the large scale fractionation of human plasma. The optimum circumstances of fractionation were determined and it was found that the majority of IgM is precipitated between 2 and 5% polyethylene glycol concentration and 1.1 and 1.8 M ammonium sulphate concentration. After a simple fractionation and gel filtration, a preparation of high purity can be obtained.


Distribution of HB antigen carriers in the population of Budapest according to age, sex, subtypes and occupation. The authors investigated serum samples of 5000 inhabitants (age 0 to 85 years) in a crowded industrial area, by means of the counterimmunoelectrophoretic method. They evaluate their results in relation of age, sex and occupation and presented literary data about the subtypes of the carriers in Budapest. They compared them with data of Hungarian and several other authors respectively. Some possible reasons of the differences are discussed and the importance of the non-parental transmission is emphasized.


A quick method for the estimation of the potency of tuberculin purified protein derivative in guinea pig. By the statiscal analysis of the data the linear regression equation and standard deviation of the dose response function of the Hungarian Reference Purified Protein Derivative of Tuberculin (HR--PPD) have been determined. From the values of reaction diameters of the HR-PPD and of their standard deviation a diagram was plotted that can be used to estimate the identity of test material by comparison with the reference preparation. The diagram meets the condition that the limits of the standard deviation of the reference and test materials together are wider than the predetermined limits of +/-20%. The inaccurate titrations can be detected with its help at once. Using the diagram, the potency of test material can be promptly estimated in the biological assay of tuberculin made in guinea pig.


Antigen analysis of Staphylococcus aureus strains sensitive and resistant to antibiotics. The analysis of the antigens produced by the disintegration of Staphylococcus aureus (Wood 46, 211, 223 strains) bacteria treated with antibiotics was carried out by the authors with immunochemical methods. It appears from the analyses strikingly that established resistance produces changes in the antigenic structure. This is manifest in the number of the antigen-antibody systems and, within the multiple system, in the character of certain antigens. The decrease in the number of the precipitogens is considerable. In the case of all the three strains, the presence of an antigen band was shown which is identical in the antibiotic-resistant bacteria, but is not to be found in the antigens of the corresponding antibiotic-sensitive bacteria. The authors' experience shows that one possibility of approaching the problem of antibiotic resistance is to clarify with immunochemical methods the differences found in the protein spectra of the antibiotic-resistant varieties.


The circumstances of freezing in the freeze-drying process of haemoderivatives. It appears from the experiments of the authors that the macroscopic changes taken place during freezing and heating could be explained by the formation of an eutectic crystalline structure in the case of human plasma and albumin solutions. The temperature interval of eutectic spot formation showed good agreement with the temperature range of initial thawing as determined by the DTA method, i.e. with the working zone freeze-drying. It was possible to determine the maximum temperature of complete solidification from the resistance curves of the haemoderivatives. Judging from the shape of the resistance curves, the phenomenon of undercooling did not emerge with the freezing rate applied. Examining the optimal freezing rate, it appeared on the basis of some quality characteristics of the freeze-dried end-product, that the best results were obtained with --30 degrees C freezing in the case of albumin and plasma, and with --45 degrees C freezing in the case of normal and iv immunoglobulins. But the authors deem it necessary to conduct further experiments in this respect.


Comparative testing of methods of protein concentration determination. The authors have carried out various tests for determining protein concentrations. They have compared the methods, and have found, as well as proved, that the spectrophotometric method I of protein determination can be employed with sufficient accuracy for the purpose of serial tests.


Examination of sterilization parameters with a view to improving the quality of infusion solutions. A determining time factor in the course of sterilization in autoclaves is the time required for killing microorganisms. Damaging of microorganisms takes its course as an exponential function of time. Taking into account this fact, the parameters of sterilization are determined by the technical standards of the equipment used for autoclaving. The authors present the sterilization problems of infusion solutions, with special regard to the sterilization conditions of heat labile preparations. The results of experiments carried out with autoclaves of different technical standards are discussed.


Significance of lymphoid atrophy in the pathogenesis of wasting syndrome. Mice with their lymphoid system made atrophic by neonatal thymectomy, showed increased sensitivity to DAD a lymphotropic cytostatic agent. Wasting syndrome developed earlier and in a higher per cent of neonatally thymectomized mice, when the animals were treated also with the subethal dose of DAD.


Effect of lymphotropic cytostatic agent in newborn and suckling mice. The sensitivity of newborn and suckling mice to a lymphotropic cytostatic agent (DAD) was found to be increased as compared to adult mice. Results indicated that a single dose of DAD being ineffective in adult mice, caused irreversible impairment in the lymphoid system of newborn and suckling mice with underdeveloped lymphoid system. This led to the development of lethal wasting resembling the wasting syndrome. On the basis of its consequences the DAD treatment, applied in newborn age, may be considered as "cytostatic thymectomy".


The effect of enhancing factor on the immunity of mice against tetanus. Enhancing factor was prepared from spleens of mice primed and reinjected with tetanus toxoid. The culture supernatant was separated by gel chromatography on Sephadex G-150, the resulted fractions were ultrafiltered and their enhancing activity was tested in vivo. The 1st fraction separated by gel chromatography proved to be active.


Comparison of antigen-type immunosorbents prepared by different ways. 7 types of IgG-containing immunosorbents were compared from different respects by using them for adsorption of antibodies. The human IgG was insolubilized by ethylchlorophormate and glutaraldehyde, thereafter it was bound to activated agarose and polyacrylamide gels and 3 new types of polyacrylamide immunosorbent were prepared by polymerizing the acrylamide in the protein solution and by coupling the protein to the matrix by different ways. Using batch technique, the ethylchlorophormate, the glutaraldehyde and some of the new polyacrylamide immunosorbents proved to be useful, but in almost every respect the immunosorbent prepared from Sepharose gel was the best.


Investigation of saliva immunoglobulins in monoclonal gammopathies. Salivary immonoglobulins of patients with multiple myeloma, lymphoid leukaemia, agammaglobulinaemia and of normal healthy adults were examined. Higher IgG level was identified in 4 cases IgG monoclonal gammopathy. In these cases extremely large quantities of IgG monoclonal protein were transmitted from serum into salivary secretions. On the basis of the results it appears that monoclonal IgA is transferred to external secretions in patients with IgA monoclonal gammopathy. High IgM level was found in both serum and saliva of agammaglobulinaemic patients. "IgM secretory component" complex could be identified in saliva. In lymphoid leukaemic patients the salivary immunoglobulins presented normal values except of a patient whose tigA lacked in serum and also in saliva.


Variations in pain complaint threshold in psychiatric and neurological patients with pain. The threshold at which noxious stimulation with a pressure algometer gives rise to a complaint of pain has been studied in neurological and psychiatric patients with pain and in two patients with fluctuating pain of organic origin. A correlation of r = 0.69 (P less than 0.0025) was demonstrated between two observers using the pressure algometer independently. Patients with organic causes for their pain had higher pain complaint thresholds. The threshold was also raised, outside the affected areas, in the two patients with fluctuating pain when the latter was more severe. Some requirements for an improved technique of pressure algometry are discussed.


Cutaneous pain threshold changes after sympathetic block in reflex dystrophies. In a group of 30 subjects suffering from sympathetic reflex dystrophies of the limbs, the sympathetic ganglia of the affected side were blocked with a local anesthetic. Using an original method, we measured the cutaneous pain threshold before the block and at prefixed intervals after the block during a period of 2 days. In all subjects the cutaneous pain threshold showed damped oscillations both in the limb ipsilateral to the block and in the contralateral one. The analysis of these oscillations showed: (a) that the sympathetic control of the cutaneous pain threshold may be exerted through a negative feedback loop (skin-afferent input-CNS-sympathetic output-skin); (b) that the afferent discharge of a limb controls the contralateral sympathetic output through central mechanisms.


Personality changes associated with reduction of pain. Of 113 patients treated in a 2-year period, for whom complete data were available, 29 who received surgery for pain relief were compared with 84 who did not, both groups receiving psychological treatment and rehabilitation. Using an analysis of covariance to eliminate pre-treatment differences, the surgery patients showed significantly greater reductions on the MMPI Hysteria and Hypomania scales, and on the invalidism scale of a Health Index, and this was associated with a significantly greater reduction of pain. These differences obtained despite a greater increase in activity levels by the non-surgery patients at the time of testing. The results support the hypothesis that the neuroticism associated with chronic pain is the result of it, and may be reversible when the pain is reduced or abolished.


Laser emitted radiant heat for pain research. Controlled radiant heat stimulation for a combined psychophysical and electrophysiological research in pain was achieved by the use of an infrared Laser beam. The computer controlled stimuli, being of very brief duration (down to 5 msec) and sharply localized, are suitable for recording of averaged evoked responses as well as for determination of pain and thermal thresholds. These stimuli can be applied to any locus on the skin. The threshold energy delivered by this technique is similar to that obtained by the Hardy-Wolff-Goodell method. Special precautions were taken to avoid injury to the skin and the eyes.


The McGill Pain Questionnaire: major properties and scoring methods. The McGill Pain Questionnaire consists primarily of 3 major classes of word descriptors--sensory, affective and evaluative--that are used by patients to specify subjective pain experience. It also contains an intensity scale and other items to determine the properties of pain experience. The questionnaire was designed to provide quantitative measures of clinical pain that can be treated statistically. This paper describes the procedures for administration of the questionnaire and the various measures that can be derived from it. The 3 major measures are: (1) the pain rating index, based on two types of numerical values that can be assigned to each word descriptor, (2) the number of words chosen; and (3) the present pain intensity based on a 1-5 intensity scale. Correlation coefficients among these measures, based on data obtained with 297 patients suffering several kinds of pain, are presented. In addition, an experimental study which utilized the questionnaire is analyzed in order to describe the nature of the information that is obtained. The data, taken together, indicate that the McGill Pain Questionnaire provides quantitative information that can be treated statistically, and is sufficiently sensitive to detect differences among different methods to relieve pain.


[17-ketosteroids in the 24-hour urine of miners with vibration disease from local vibration exposure]. The 17-ketosteroid level in the urine secreted in 24 hours s studied in miners with vibration disease. The case material is analyzed according to age, working service, clinical syndromes and stage. It is demonstrated that the continuous effect of local vibrations lead to inhibition of the adrenal function, manifested by a 17-ketosteroids fall. Such a lowering is assumed as one of the adaptational syndrome-manifestations. Regulation of corticosteroid secretion is discussed in the light of complex interrelations--neuroendocrine, biochemical and homeostatic. The role played by oxidation processes is also emphasized. 17-ketosteroids content in the urine has certain diagnostical value, irrespective of the fact that its lowering is by no means a specific manifestation of the vibration disease.


[Determination of the optimum of physical loading in relation to the maximum potentialities of the body]. Determination of the maximum capacity of work is essential for prophylaxis, and is closely related to the problems of scientific organization of  work still awaiting solution. The maximum oxygen consumption among female textile workers ranges between 2.2 1/min and 1.6 1/min, while the reak heart rate--from 167 to 153 beats per minute. Allowable physical exertion among female textile workers should not exceed 3.5 kcal/min.


[Biological action of cement dust in intraperitoneal and intratracheal tests]. The morphological changes occuring upon intraperitoneal and intratracheal application of cement with free silica content amounting to 1.30% are described. Initially, the changes in the peritoneal cavity are mainly necrotic and exudative, while after subsiding, the granulomas formed around the uneliminated dust particles predominate without exhibiting fibrotic phenomena. Upon intratracheal application, lesions typical of cement occur, coined by the authors with the term "experimental cement pneumopathy". It is a matter of changes presenting as "pseudopolyp" formations around the small bronchi and bronchioli, slipping into their lumen and thus causing its obturation. In the final stages of the experiment, a definitive peribronchial fibrosis with perifocal and subpleural emphysema is developed around the involved bronchi.


[Simultaneous determination of trace amounts of zinc, cadmium, lead and copper by the method of anodic voltammetry using factor experimental design]. Using the method of factor planning of the experiment, the author studies and demonstrates the influence exerted by the potential and time of electrolysis, and by the concentration of the background and elements on the heights of anodal peaks upon simultaneous determination of zinc, cadmium, lead and copper microconcentrations. On the ground of statistical elaboration of the results, the optimal condition for polarographic determination through anodal voltamperometry are outlined. According to the cyclic voltametry method, the electrod processes reversibility for zinc, cadmium and lead, as well as the incomplete reversibility for copper are established; the number of electrons participating in the electrochemical reaction are found using the method of gas coulometry. The possibility of simultaneous determination of the four elements' ultramicroconcentrations after the method of voltamperometry with enrichment is proved. The standard deviation is in the range 3.02 to 4.9.


[Electron microscopic methods of studying pollution in the work environment from submicroscopic aerosols]. The existing method of electron microscope study of working environment pollutions caused by submicroscopic aerosols are summed up and subjected to critical analysis. More particularly, reference is made to the methods of detecting dust particles in the disperse medium for electron microscope study, to determination of the scope of application of these methods, as well as the determination of the effectiveness of detecting filters for submicroscopic aerosols, using electron microscope techniques.


[Reflection of gastric peristalsis influence on tis transmucous potential]. Some of the causes owing to which measurement of the gastric transmucous potential in animals and humans has failed to find practical application hitherto are listed. A method developed for operative agar bridges implantation within the abdomen of experimental animals is described. Several types of waves are observed in the electrograms of the gastric transmucous potential of rabbit and rats, obtained in the fashion outlined above. It is established that by changes in amplitude and by frequency, the type of waves just mentioned correspond to the peristalsis of the stomach. It is presumed that these waves are produced by changes in the gastric wall physical parameters upon contractions of the same.


[Effect of short-term fasting on liver lysosomes in rats, biochemical studies (preliminary report)]. The total activity of four lysosome enzymes--acid phosphatase, beta-glucuronidase, alpha-glucosidase and beta-N-acetylglucosaminidase--is studied in liver homogenate at 2, 6, 24 and 48 hours after the last meal in rats, previously sustained on a single-daily-feeding regimen. In addition, the free activity (percentage of the total) of the latter enzyme and its activity in the serum as well are investigated. A rise of the total activity of the first three enzymes is recorded within 48 hours after the beginning of starvation. The free activity of beta-N-acetylglucosaminidase shows an increase at 48 hours, while its activity in the serum--as early as 24 hours. The changes described above are interpreted as an expression of lysosome membrane permeability enhancement under fasting conditions.


[Changes in lysosome enzymatic activity during fasting following a regimen of once-a-day or all-day feeding]. The influence of fasting for 24-96 hours is studied in rats, subjected in advance to a regimen of all day long access to food, to a single feeding in 24 hours. Total activity of beta-N-acetylglucosaminidase (beta-N-AcG1), acid phosphatase (AP) and beta-glucuronidase, as well as the free activity of the first two enzymes are studied in liver homogenate. The activity of beta-N-AcG1 is determined in blood serum also. A rise of total beta-N-AcG1 activity is recorded in liver homogenate, increasing parallel to prolongation of the fasting period. The changes in free activity of AP and beta-N-AcG1, and in the plasma activity of the latter enzyme are similar. The above described changes are more strongly pronounced in the groups subjected in advance to a single feeding regimen. These changes are interpreted as an expression of the active participation of lysosomes and their enzymes in the transition to endogenic nutrition. The lysosome membrane proves to be more vulnerable to damage by starvation among the animals previously maintained on a single feeding regimen.


[Study of serum beta-N-acetylglucosaminidase activity in white rats treated with 1,2-dichloroethane]. In the course of a three-month long, chronic experiment using white male rats, the organic solvent 1,2-dichlorethane was administered per os at the following doses: 1/5000, 1/1000 and 1/200 LD50. The activity of the lysosome enzyme beta-N-acetylglucosaminidase is studied. A statistically significant increase (p less than 0.02) is established in the two higher doses.


[Changes in the liver transport of bile pigments in certain forms of jaundice under the influence of novobiocin and luminal]. The novobiocin and luminal test application increases the possibilities to differentiate premicrosome from postmicrosome jaundice and extends the knowledge on hyperbilirubinemia pathobiochemistry. Novobiocin (an antibiotic) inhibits the conjugation and glucuronidizing of bile pigments. Accordingly, the novobiocin test is strongly positive in any premicrosome jaundice form--Gilberts's disease, posthepatitis hyperbilirubinemia (PHHB) and hemolytic jaundice. It is negative in hepatocellular and hepatocanalicular jaundice, and in Dubin-Johnson's syndrome. In premicrosome jaundice with fluctuating bilirubinemia and normal bilirubin level at the time of examination, the novobiocin test may bring about manifestation of a latent or temporary compensated defect which proves to be most helpful in diagnosing. It is assumed that hemolytic jaundice is caused, apart from bile pigments hyperproduction, also by concomitant disorders in the intrahepatal transport of bile pigments. The latter hypothesis is corroborated by the data of the study. The luminal test is likewise markedly positive in premicrosome jaundice, and negative--in chronic hepatocellular and hepatocanalicular jaundice. In some instances with slight defect in the intrahepatal transport of pigments, the luminal test accounts for normalization of bilirubinemia and of the direct to total bilirubin ratio. The test is moderately positive in the syndrome of Dubin-Johnson. The latter fact supports the hypothesis that luminal, alongside the effect on transport mechanisms, exerts influence on bile pigments excretion also.


[Study of liver glucuronidase function in indirect hyperbilirubinemia and liver cirrhosis]. A discussion is made of the basic peculiarties and differences in the clinico-laboratory profile in various forms of pre- and postmicrosome jaundice. The importance of direct to total bilirubin ratio, and of quantitative bilirubin and urobilinogen bodies' determination in the urine is stressed. Bile pigments conjugation by the hepatic cells and free bilirubin conversion to glucuronose may be also assayed by resorting to some additional tests. The test with N-acetyl-paraaminophenol (NAPA) provides for an indirect assessment of the liver's glucuronidase function and has a good informative value. It is optimally characterized by the percentage of free (non-conjugated) NAPA with respect to the total. The latter indicator is normal in chronic hepatitis and in Dubin-Johnson's syndrome, and is at the uppermost normal limit in  hepatic cirrhosis and cholestatic jaundice. It is strongly increased (in the average three times with respect to normal values) in Gilbert's disease and posthepatitis hyperbilirubinemia (PHHB). It affords some information on the severity of the defect in transport of bile pigments in the mentioned affections. In hemolytic jaundice a normal percentage of free NAPA is usually found. Glucuronose conversion of bilirubin hardly plays an essential role in the pathogenesis of hyperbilirubinemia i the listed above diseases. This is also confirmed by the NAPA test, performed subsequent to novobiocin loading. The percentare of free NAPA under the conditions just outlined is furthermore increased in Gilbert's disease and PHHB, while in hemolytic jaundice it remains within normal limits. In Gibert's disease and PHHB, a strongly pronounced delay in the excretion of substances is noted. Not infrequently, a similar disorder is also observed in hepatic cirrhosis. It is interpreted as an expression of an overall disturbance in hepatic blood flow and function of the heavily affected hepatic parenchyma.


[Trace element and heavy metal content in the basic types of Bulgarian flour]. The content of total ashes, copper, manganese, zinc, molybdenum, lead and cadmium is investigated in the three basic Bulgarian flour brands--type 500, type 700 and type 1150. It is found out that the content of all the microelements under study shows an increase from white (type 500) to darker flour (type 1150). Zinc and manganese content is the highest in all three types of flour investigated, while cadmium content is the lowest. No essential difference is established in the individual microelements' content of the flour from various regions of the country, except for the higher content of molybdenum, found in the flour obtained from the Plovdiv mills.


[Morphological changes in the internal organs and endocrine glands of rats subjected to deficient nutrition and fasting]. Pathological studies on the internal organs, endocrine glands inclusive, are carried out in white rats under conditions of deficient alimentation and fasting. The results of the study show that complete starvation with preceding full value or restricted (2 hours daily) feeding brings about a variety of morphological reactions in the internal organs and endocrine glands. The liver proves to be the most sensitive to reduced food supply it shows a marked response with fatty dystrophy and subsequent atrophy. Next ranks the kidney. Myocardium, spleen, thyroid gland, adrenals and testes fall in the third group--with a weaker and rather delayed response. Small intestine, lung and hypophysis do not show changes worth noting. The investigations performed are related to the effect exerted by starvation and deficient nutrition, assumed as a stress factor for the organism.


[Changes in protein metabolism in white rats with limited feeding and a varying physical load]. Changes in some protein metabolism indicators are studied in white rats at different levels of the energy balance. It is established that the level of the so-called labile protein in the organism is closely related to the level of energy metabolism and also, that it is not invariably directly dependent on protein concentration within the organism. The inference is reached that adaptivity of protein metabolism is manifested not merely through changes in the value of proteins, which might be employed in the capacity of reserve, but also through changes in the degree of their lability, resp. in the ability of the organism to mobilize them. The amount of protein reserves depends rather more on the increased protein intake with the while food, while the degree of reserve protein lability is related to a higher degree to the muscular activity of the organism. Restricted motor activity combined with a high protein intake, against the background of an even minimum hypercaloric feeding, leads to a considerable reduction of protein reserves. Deficient feeding combined with restricted motor activity leads to reduction both of the amount and lability of reserve proteins. Physical exertions have a favourable effect on the ability of organism both to increase its protein reserves and to mobilize them, with the latter being rather pronounced under conditions of limited feeding. It is stressed that excretion of nitrogen, urea and creatinine in the urine in conditions of protein poor diet is in a position to afford essential information on the adaptability of protein metabolism within the organism.


[Experimental studies of the effect of the restoration of a balanced diet on the endocrine glands injured by food deficits]. The problem of the extent to which changes in endocrine glands in case of protein or fatty deficiency are reversible has a great theoretical and practical bearing. Its elucidation appears to be particularly relevant in the management of the various forms of deficient feeding where restored whole-food diets exert a pronounced therapeutical effect. However, literature data on the issue are very scanty and rather dissenting. The structural changes in adenohypophysis, thyroidea, adrenals and sex glands were studied in 72 albino rats of the Wistar line which, following treatment with a diet poor in proteins and fats, were subjected to a recovery regimen by feeding them whole-food diets. For the purpose, histomorphological and histochemical tests were used. It was established that while in the animals deprived of fats, realimentation estrored the mophological profile of all the glands under study, among the rats fed protein poor diets, irreversible tissue changes were found in the adrenals and gonads. The results obtained are related to the direct action of the nutrient deficit, or to its deleterious effect on the tropic secretion of the hypophysis.


[Changes in the serum activity of lysosome enzymes in rats after application of the insecticide propoxur (Baygon)]. The effect of repeated peroral introduction (4 times) of 1/4 and 1/20 LD50 of monomethylcarbamate insecticide Propoxur (Baygon) on the activity of two lysosomal enzymes (beta-N-acetylglucosaminidase and alpha-mannosidase) is studied in the serum of white male rats with starting weight 300 g. Upon using the higher dose, a statistically significant rise (p less than 0.02) of the activity of either of the enzymes is established. The results obtained are interpreted as a sign of impaired permeability of the lysosomal and cell membrane.


[Study of glucose resorption during rhythmic protein feeding in a chronic experiment on white rats]. In three experimental groups of white rats receiving cacein in the morning, at noon and at night, over a period of one month, glucose resorption was studied in the hours of casein alimentation. The method of accumulating preparation from the mucosa "in vitro" was employed, and parallel to glucose resorption, maltase activity was also investigated. The results obtained are discussed in the light of modern concepts on membranous digestion and active transport, and more particularly, on interactions of the monomers at membrane level. Interpretation is made of the marked resorption of glucose, observed in the experimental group receiving casein at noon, and the possibility of practical application of the results recovered in rational dietetic nutrition is discussed.


[Changes in the gonads and reproductive capacity of white rats after oral maneb poisoning]. Changes in the gonads and reproduction capacity of white rats following oral intoxication with maneb are studied. The preparation at doses 1/10, 1/50, 1/100 and 1/5000 LD50 is administered to the starting generation of white rats twice weekly. Changes in the gonads--biochemical, histological, histoenzymatic and electron microscopic--are established, as well as a capacity for reproduction of the starting I and II offspring. The results show a clearcut gonadotropic effect of the preparation, manifested by morphological changes in the starting generation, and by changes in fertility, gestation, survival and lactation of the starting I and II offspring.


[Cumulative action of Gramoxone and Reglone]. Two dipyridilium herbicides--Gramoxon and Reglon, at doses 1/3, 1/10 and 1/20 LD50--are administered to rats per os, daily over a period of one month. The values of the cumulation coefficients (CC) are calculated on the ground of lethality data. The clinical picture of intoxication caused by the above preparations is also studied. Daily, one-month long introduction of LD50 fractions demonstrates the presence of a cumulative action, much more strongly pronounced for Gramoxon as compared to Reglon. Parallel to reduction of the doses given, the cumulation effect di minisches and at 1/20 LD50, it is but weakly pronounced. The latter fact warrants the assumption that although being comparatively toxic, the dipyridium herbicides do not represent a serious hazard in terms of sustaining chronic oral intoxications. This is furthermore corroborated by the clinical picture of intoxication by either of the preparations at the different dose levels employed. The dipyridium herbicides Gramoxon and Reglon do not form storage depots. In this particular case, it is a matter of functional cumulation subsequent to decompensation of the regulatory mechanisms ascribed to the toxic effect of the preparations, exerted mainly on the respiratory system.


[Comparative study of the changes in the EEG and cholinesterase activity in experimental Dipterex poisoning]. A systematic study is conducted on cats, poisoned with the organophosphorus insecticide Dipterex. The changes in spontaneous and induced cortical activity along with those in serum and erythrocyte cholinesterase after intraperitoneal and intramuscular injection of Dipterex are investigated. Against the background of lowered cholinesterase activity, recorded in all the experiments , the changes in EEG appear to be discrete and inconstant. Uron single treatment with Dipterex, desynchronization prevails in the spontaneous EEG, whereas in the responses induced by light stimulants an increase of delayed negative potentiale prevails. Upon repeated Dipterex introduction, theta-like waves appear, associated with activation of paroxysmal manifestations existing in advance. Finally, the correlation between changes in cholinesterase activity and EEG is discussed.


[Metabolism and the dynamics of the urinary excretion of Sayfos in rabbits]. The splitting of Sayphos into metabolites inhibiting indoxyl acetate esterase activity is investigated. Also the dynamics of Sayphos excretion in the urine is studied. It is established that in the urine of unpoisoned rabbits, normally a compound with Rf 0.79 is contained, inhibiting indoxyl acetate esterase activity. Sayphos and metabolite I with Rf 0.08 are demonstrable both in the blood and urine at 2 hours after peroral introduction of the poison. Within 24 hours no traces of the pesticide and metabolite I are discovered in the blood, and in the urine--within 96 hours since the beginning of the experiment. Most of the indoxyl acetate esterase activity inhibitors (Sayphos and metabolite I), excreted via urine (mean 95%), are emitted up to the 24th hour inclusive.


[Determination of the minimal times for safe work following the Sayfos spraying of tobacco]. The semidisintegration period of Sayphos over tobacco leaves is determined--2.5 days at angular coefficient of the disintegration straight line K=0.12 1 ppm/ 1 mg/kg concentration of Sayphos over tobacco leaves is considered as harmless and accordingly safe for work. A table for minimal terms of safe work computation is also suggested. Because of the slow Sayphos decomposition in soil, the preparation should be employed but once--after the planting of tobacco.


[Appraisal of the feasibility of the accepted Bulgarian MPEL for lead in the air of the working environment using modern criteria]. The MAC for lead in the workplace atmosphere adopted in Bulgaria, amounting to 0.01 mg/m3, appears to be much lower than abroad. Upon investigation of groups of workers employed in the lead mining and processing industry, working under conditions of lead exposure up to 0.10 mg/m3 and exceeding 0.11 mg/m3, no changes were found in the delta-amino-levulinic acid and coproporphyrin level in the urine--the early signs of lead damage--nor in plumburia mong the workers exposed to lead concentrations up to 0.10 mg/m3 which is a concentration exceeding ten times the MAC accepted in this country. A reassessment of the later on the basis of up-to-date biochemical criteria is deemed necessary.


[Action of the herbicide Ramrod on the embryogenesis of white rats]. The embryotoxic and teratogenic activity of the acetanilide Ramrod is subjected to experimental testing. Studies are conducted on 103 white unbred female rats, to which the preparation was administered throughout the full gestation period, at doses 1/5, 1/10, 1/30 and 1/40 LD50. Following in reduction of the preparation, an increase in the total embryonal lethality was noted, conditioned entirely by the considerable rise, as compared to controls, of the pre-implantation deaths of embryos. The embryotoxic action of the preparation was furthermore manifested with a decrease in body weight and in the craniocaudal fetal sizes. Upon giving 1/5 and 1/10 LD50 Ramrod, a slight teratogenic effect was recorded. Ramrod at dose 1/40 LD50 exerted no effect whatsoever on embryogenesis.


[Problems of work hygiene in the manufacture of penicillin and streptomycin]. During the production of penicillin and streptomycin, substantially high concentrations of butyl alcohol and butylacetate are measured in the working environment atmosphere. The penicillin and streptomycin dust appears to be the chief unfavourable factor of the workplace in the drying, sorting and packing processes of the antibiotics. An unfavourable microclimate is observed only in the fermentation sections-- in the extraction and chemical purification, and particularly, in the drying process of the two antibiotics. The specific features of the working activities performed by vial examiners and sorters constitute factors predisposing to visual analysor strain. The latter might be also explained by changes taking place in the working ability and steadiness of attention in the course of the working shift.


[Early criteria for the diagnosis of chronic carbon monoxide exposure]. A clinico-laboratory study is carried out on 100 workers from the coke-chemical plant "Mining Complex Kremikovtzy", exposed to chronic effect of carbon oxide, at concentrations close to MAC. A wide range of laboratory indicators are employed for the purpose: hematologic, biochemical and enzymatic. Increased alkaline phosphatase and aldolase activity, increased fibrinogen values and leucineaminopeptidase inhibition are pointed out as being most demonstrative of the early carbon oxide effects on the organism.


[Study of the changes in serum enzyme activity in acute phenol poisoning]. The activity of some serum enzymes is followed up under conditions of acute phenol intoxication. Analysis is made in dynamics within 2, 12 and 24 hours after toxic substance administration. An increase in the activity of the parenchyma non-specific enzymes SChE, LDH and LAP is noted. No changes are established in the activity of Al.Ph. The hyperfermentemia present is most likely attributable to disturbed cellular membrane permeability and cell destruction.


[Neurovascular reactivity in vibration disease]. It is pointed out that neurovascular derangements are among the earliest and primary changes in individuals exposed to the effect of vibrations. The manifestations of vasoconstriction with a tendency for generalization prevail. Angiospasm associated with hypopallesthesia, hypalgesia and hypothermy in miners with continuous service in hard rocks processing, using high-frequency drilling hammers, constitute in many aspects the complex of symptoms, typical of the vibration disease. It is emphasized that neurovascular reactivity might be assumed as having certain diagnostic-prognostic significance provided it is estimated against the background of the other clinical data and indicators.


Superposition of chromatic error and beam broadening in transmission electron microscopy of thick carbon and organic specimens. The chromatic error is calculated using our scattering cross sections obtained from contrast experiments and a distribution function of energy losses from Misell and Burge. The assumed ratio of total inelastic and elastic cross sections was 3.5. Monte-Carlo calculations were performed for the multiple scattering problem of thick carbon specimens using these values for single scattering. As expected, a minimum confusion of the chromatic error disc exists at underfocusing. The half width broadening of an edge is in good agreement with experiments at 100 keV if the experimental method of determining the half width is also taken into consideration theoretically. The lateral displacements of electron paths normal to the direction of the electron incidence, which give rise to poorer resolution at the bottom of a thick specimen in scanning transmission electron microscopy, cannot simply be added to the chromatic error in the normal mode of transmission electron microscopy. Calculations show that there is no difference in edge resolution at 100 keV to be expected, in agreement with experiment. With increasing energy, the influence of beam broadening increases relative to the chromatic error. Considering only the chromatic error (1-2 nm), at 1 MeV and optimum defocus details on the top of a 2 micron specimen will be imaged with nearly twice the value of edge half width as they will at the bottom.


Thick specimens in the CEM and STEM. Resolution and image formation. A theory of resolution and image formation is presented for thick amorphous specimens in transmission electron microscopes. Eight modes of operation are considered, four in the scanning transmission electron microscope (STEM) and four in the conventional electron microscope (CEM). A thick specimen is defined here as one in which the resolution of detail is limited by plural scattering of the electron beam. In practice this includes films on the order of a micron in thickness. An analytic theory of plural incoherent scattering is developed which is general with respect to material and beam voltage. The theory gives the distribution of elastically scattered electrons as a function of transverse coordinate and angles, and is directly applicable to optical systems. The theory applies to all thicknesses normally encountered, and includes thin specimens as well as thick specimens. Criteria are proposed for evaluation of the quality of microscope images, and the modulation transfer function is applied to determine some practical estimates of picture quality. The STEM is found to have distinct advantages over the CEM for thick specimens. For a carbon specimen one micron thick a STEM operating in bright field at 90 keV produces an image which is roughly equivalent to that of a CEM operating in bright field at 1 MeV. Improvement can be obtained in the CEM by filtering out eneryg-loss electrons which degrade resolution due to chromatic aberration. This results in a reduction in signal intensity and usable thickness, however.


The microanalysis of light elements using transmitted energy loss electrons. The use of transmitted energy loss electrons is shown to hold considerable promise for the elemental analysis of light elements. In this technique, those electrons which have lost energy in exciting characteristic inner shell atomic levels are detected rather than X-rays resulting from the decay of the excited levels. The advantages of this technique are (1) a large fraction (0.1-1) of the information-carrying energy loss electrons can be detected, and (2) for each excited level, one energy loss electron is produced independent of the fluorescent yield. Thus the technique potentially offers higher sensitivity than X-ray analysis. We have begun a program to evaluate this technique both theoretically and experimentally for electron probe devices. First, we have developed the necessary theoretical framework to make predictions concerning relevant quantities of elemental analysis such as the minimum detectable mass (MDM) and mimimum detectable mass fraction (MMF). The results of these calculations for thin specimens indicate a potential reduction in the MDM by up to three orders of magnitude and in the MMF by up to 500 through the use of transmitted energy loss electrons rather than X-rays; the advantages over X-ray detection being greater for lower atomic number. Second, we have begun experimental measurements to verify our predictions. These experiments were performed in a field emission scanning microscope with known limitations in collection efficiency, but the results indicate the validity of the basic assumptions and also aid in the design of an instrument which can fully exploit this technique. The experimental results obtained indicate the ease of detection of characteristic K-shell energy levels in elements as light as lithium and indicate the mass detectability of less than 10(-18)g.


Development of methodology for low exposure, high resolution electron microscopy of biological specimens. Specimen damage resulting from inelastic scattering is one of the factors that limits high-resolution electron microscopy of biological specimens. We have, therefore, sought to develop a method to record images of periodic objects at a reduced electron exposure in order to preserve high-resolution structural detail. The resulting image will tend increasingly to be a statistically noisy one, as the electron exposure is reduced to lower and lower values. Construction of a statistically defined image from such data is possible by spatial averaging of the electron signals from a large number of identical unit cells. In this paper, we have first investigated the theory pertaining to the attainable resolution as a function of the electron exposure, the magnification, and several other relevant parameters. In addition, we report experimental results obtained with a commercial image intensifier and with nuclear track photographic emulsion, both of which are highly sensitive recording devices. Usable images can be recorded and processed at exposures in the image plane as low as 10(-3) electron/micron2 (1.6 x 10(-14) coulomb/cm2).


On dark field techniques in transmission electron microscopy. Different dark field techniques in transmission electron microscopy are investigated. In particular, a displaced aperture technique is developed, which produces high quality off-axis dark field images. The essential feature of the method is that the chromatic aberration of the objective and intermediate lenses is compensated for with the aid of a one-stage beam deflector in the object plane of the intermediate lens. In addition, the image distortion and the effect of the curvature of the image field are minimized by reducing the coefficient of sperical aberration of the intermediate lens. Diffracted beams, forming angles alpha up to 2.5 degrees with the optical axis, can be used for dark field imaging. Resolutions better than 30 A for alpha = 2 degrees, and 17 A for alpha = 1 degree, are obtained.


Electron microscope images of mercury atoms bound to DNA filament. Ultra-fine grids with holes of a few hundred angstroms in diameter were made from tropomyosin for specimen supporting media. DNA was mounted on the grid. Microscope images were obtained demonstrating one double-stranded DNA filament bridging a hole. Using mercurated DNA a few filamentous images were observed in a bridge, and series of faint fine sports were recognized along an edge of a hole. These spots were interpreted as the images of single mercury atoms bound to the filament. The control experiment was made on unstained DNA, some images of which showed only uniform intensity over the bridge, whereas others were disturbed to some extent by noise presumably due to extraneous molecules coating the filament.


A specimen preparation technique for transmission electron microscopy of surface layers. A TEM specimen preparation method is described, with the aid of which electron transparent foils can be obtained across the external surface of a specimen. After careful pre-treatment, steel specimens have been electrolytically coated with nickel. Conventional thinning in a plane cutting the substrate-coating interface, gave thin foils displaying the internal structure as a function of depth under the initial free surface. The method has also been applied to minute metal particles, of dimensions too small to allow manipulating and foil preparation by conventional methods. Image examples are shown, and the applicability of the method is discussed.


A method of using the incident beam tilt as a eucentric goniometer in transmission electron microscopy. The principal difficulties in constructing and operating a eucentric specimen tilting goniometer in a transmission electron microscope are discussed, together with the goniometric function of the incident beam tilt. The latter function is found easy to operate in a eucentric manner. The imaging beam then will have a non-axial path, which will increase particularly the field chromatic aberration. Earlier, however, a technique for the compensation of the chromatic aberration during displaced aperture dark field image formation has been developed. In combination with this technique, it proved possible to use the ordinary incident beam tilt as a eucentric goniometer. Image sequences were obtained, with accurately varied diffraction conditions. The tilt angles and the direction of the tilt axis can be very accurately determined from the displacements of the diffraction pattern.


Aperture contrast in thick amorphous specimens using scanning transmission electron microscopy. The contrast observed in thick amorphous specimens using a scanning transmission electron microscope (STEM) can be considerably improved by the use of an optimum collector aperture angle. The size of this angle can be calculated by considering the variation of electron current transmitted through the specimen as a function both of the specimen thickness and of the angle of collection subtended at the specimen. Typically these calculations predict optimum angles to be several times the half-width of the elastic scattering distribution, often 10(-1) rad or more. Observations of biological sections of up to 2 micron in thickness using scanning attachments of commercial transmission microscopes have verifie these results at beam voltages of 50, 100 and 200 kV. Wide angle convergent beam diffraction patterns were used to give accurate values of the effective angles represented by the various collector apertures. Once the linearity of the detector-amplifier system had been established, operation in a line modulation mode enabled quantitative measurements to be made of the image contrast. Such measurements also offer a quick effective method of comparing electron beam penetrations.


High resolution imaging properties of the STEM. The effect of the finite size of the atom on the resolution of the STEM is investigated. When the probe size becomes comparable to the size of the atom, the quality of the image depends on the scattering properties of the atom as well as the distribution of electrons in the probe. A technique for calculating the image of a single atom is developed by expanding the scattering amplitude. This allows the image of an atom or its spatial frequency to be expanded into various components. The specific case of dark field contrast formed with elastically scattered electrons is considered. The coefficients of the components are evaluated for carbon and thorium using complex scattering amplitudes derived from relativistic Hartree-Fock-Slater wavefunctions. The coefficients are evaluated for a 100 keV microscope using an immersion type objective lens whose aperture is limited to 12 mrad by primary spherical aberration and a 100 keV microscope using the same objective lens in conjunction with a corrector lens for spherical aberration. Secondary spherical aberration limits the objective aperture of the corrected microscope to 30 mrad.


Magnification variations in reflection electron microscopy using diffracted beams. In reflection electron microscope images obtained using electron beams diffracted at a small angle from the surfaces of bulk specimens, it is observed that the magnification in directions almost parallel to the incident beam appears to increase rapidly with distance from the in-focus position in both directions. An explanation for this effect is offered in terms of the curvature of the lines of energy flow around the cross-over of the electron beam formed by the condenser action of the fore-field of the objective lens.


Averaging of low exposure electron micrographs of non-periodic objects. The investigation concerns the possibility of extending to non-periodic objects the low exposure averaging techniques recently proposed for non-destructive electron microscopy of periodic biological objects. Two methods are discussed which are based on cross-correlation and are in principle suited for solving this problem.


A method for the improvement of the visibility of transmission electron microscope images. A method is presented of improving the visibility of transmission electron microscope images in any situation in which a high resolution in only one chosen direction is of interest. The technique is based on the use of slot shaped objective apertures. Such apertures are of reduced area relative to a circular aperture giving the same all round resolution. The background intensity due to inelastically scattered electrons is thus reduced. The aperture device developed is described, while the value of the method is demonstrated by its application to the observation of dislocations. Further possible applications are indicated.


Topographical contrast in the transmission electron microscope. An adaptation of the Foucault method for topographical imaging in the transmission electron microscope is described in detail. The image contrast is produced by selection of electrons which have suffered differential phase retardations in the specimen inner potential. Surface or interface displacements produce bright or dark image contrast, and the ultimate resolution approaches that of the atomic scale. The imaging method is applied in studies of both amorphous and crystalline objects. The possibility of performing quantitative measurements is demonstrated by the estimation of the inner potential of crystalline MgO.


[Development of infestations of corcyra cephalonica (Stainton, 1865) (Lepidoptera, Galleriidae) in some alimentary substrates (author's transl)]. Experiment to study the evolution of infestations of Corcyra cephalonica in peeled peanuts, grain corn, wheat flour and grain coffee, were carried out in Santos and in São Paulo (State of São Paulo, Brazil). In the experimental conditions, more emergence resulted from peanuts followed by grain corn and third by wheat flour; a very small number of moths emerged from the grain coffee. The place did not interfere with the results.


[Adenocarcinoma of the kidney in the dog. A case report treated by nefrectomy (author's transl)]. This authors describe a renal adenocarcinoma in a six years old made Saint Bernard dog. The clinical and radiological changes are presented. Urine and blood examination were also studied. Surgical treatment (nefrectomy) and results justify the present communications. Papillary adenocarcinoma is the histopathological diagnosis.


Analgesic activity of dimeric proanthocyanidins--Preliminary experiments. Pharmacological experiments with cacao and avocado proanthocyanidins were performed. Analgesic action was measured by the heated plate method: mice receiving 80mg/kg of the drugs showed a behaviour similar to those receiving morphine. Potentiation of "sleeping time" suggests a possible depressive action on the central nervous system.


[Toxicity of insecticides-acaricides were studied for three phytoghagous mites (Acari: Tetranychidae) using two different laboratory methods (author's transl)]. The aim of this work was to learn the toxicity of acaricides: monocrotophos, chlorobenzilate and chlorphenamidine when used as an immersion and as a spray on the phytophagous mites, Tetranychus (T) urticae, Tetranychus (T) cinnabarinus and Tetranychus (T) ludeni under laboratory conditions. It was concluded that the mite T. urticae was sensitive to chlorphenamidine at least when used as a spray without killing them in a significant level. However the mites T. cinnabarinus and T. ludeni were sensitive to chlorphenamidine when using immersion method. The monocrotophos and the chlorobenzilate were toxic of the three species of mites using though the employed methods.


[Isolation of rabies virus from brain, salivary and interscapular glands, heart, lungs and testis of the bat Desmodus rotundus, in the State of São Paulo (author's transl)]. Rabies virus was isolated from the brain, salivary and interscapular (brown fat) glands, heart, lungs and testis of naturally infected vampire bat Desmodus rotundus found paralyzed in the day at Barueri, São Paulo State. The rabies virus isolations were made by intracerebral inoculation in 4-5 days and 30 days old mice. The virus strain was identified as rabies virus by the Sellers and Faraco (Mann) techniques, the fluorescent antibody test and intracerebral inoculation of mice. The isolation of virus from lungs and testis was made only in suckling mice. Only one of eight and two of eight mice inoculated died with rabies.


[Analysis of cupric fungicides by complexometric potentiography (author's transl)]. This paper deals with a description of a potentiographic complexometric technique developed for determining copper in cupric fungicides. It is precise, accurate and specific in presence of zinc and manganese (iron and aluminium should be separated). Its great advantage in comparison with the classical method is the quickness.


[Isolation of rabies virus from an insectivorous bat Molossus obscurus (Geoffroy, 1805), in the State of São Paulo (author's transl)]. Rabies virus was isolated from insectivorous bat Molossus obscurus found in a semi-paralyzed condition, in broad daylight, in Campinas, São Paulo State. Suckling and adult mice inoculated intracerebrally with a 20% suspension of bat brain showed typical rabies symptoms within eight days. The mortality of inoculated mice was 100%. Negri bodies were seen in the brains of infected mice by Sellers and Fraco's methods. Rabies antigens was found in the brains of inoculated mice by fluorescent antibodies test.


[The complement-fixation test in rabies. I. Antibody titer of vaccinated dogs (author's transl)]. Complement-fixation test based in 50% hemolytic end point was applied to investigate the immune status to rabies of dogs vaccinated with heigh egg-passage Flury vaccine. The complement-fixation titer was compared with serum neutralization results. Twenty-five sera was employed and the complement fixation titer varied of 0 to 256. Three sera was anticomplementary. The results indicated a lack of quantitative correlation, but was found a qualitative correlation between the two methods.


[Experimental trial to reproduction enzootic haematuria in cattle by feeding bracken fern [Pteris aquilina (Kuhn)] (author's transl)]. Cattle were fed with a diet containing bracken fern in order to study the development of chronic bovine haematuria. The experimental 25 animals were randomly divided into 5 groups and such groups received different amounts of the plant. All groups were fed for 36 months, while no clinical effect of the disease was noted. After that time, the supplement of bracken fern to the diet was suspended and the animals still remained under observation. One of the animals (from group I) exhibit haematuria one month after the fern was removed from the diet. In the same occasion, four animals were slaughtered and only one of them presented haemorragic lesions in the urinary bladder. After 34 days another four animals were slaughtered and 114 days later three more were killed. All animals were chosen randomly and in spite of no clinical signs of the disease, all of them presented haemorragic lesions in the urinary bladder. The results obtained in this experiment confirmed that bracken fern (Pteris aquilina) is responsable for the development of chronic bovine haematuria in cattle. The disease is challenged by continuous ingestion of small amounts of bracken fern during a long period of time.


[Bacteriological study of the intestinal flora of bats (Desmodus rotundus) (author's transl)]. Stools of 100 bats trapped in the town of Anhembi, State os São Paulo, Brazil, were examined bacteriologically. Hemolityc and non hemolytic strains of Escherichia coli were found most frequently (29.5%) followed by Proteus group (27%) and Staphylococcus (20%). From nine samples of stools the authors isolated Salmonella typhimurium.


[Blood cultures-bacteriological and drug resistance culture (author's transl)]. Blood cultures of 24 patients from the Hospital das Clinicas da Faculdade de ciências Médicas e Biológicas de Botucatu showed a prevalence of gram-negative isolates (83%) over gram-positive (16%). Among the microorganisms Salmonella typhimurium was the most frequent (25%) followed by Klepsiella sp. (21%) and Escherichia coli (17%). It was also observed that the main cuase of death was the largest occurrence of Salmonella typhimurium and Pseudomonas aeruginosa among the isolates. Regarding drug resistance gentamycin revealed more active than other antibiotic tested.


[Hematological studies on cows pasturing on Brachiaria radicans napper in winter time (author's transl)]. A group of six adult cows Holstein-Frision was left grazing on a pasture formed exclusively with Brachiaria radicans Napper. This investigation was was undertaken during the rather dry winter with the graminea showing a low nitrat content. The animals failed to present any of the typical simptoms of intoxication and the weekly clinical and hematologycal examinations detected a hyperchromic macrocytic anaemia eventually jointed to anisocytosis and basophylic stippling in the red cells. The anaemia was controlled by removing the animals from the pasture.


[Studies on guinea pig fed on Brachiaria sp. (Tanner Grass) (author's transl)]. The investigation was developed with 80 female guinea pigs weighing about hundred grams. housed in groups of 15 or 20 animals. The daily treatments were: Brachiaria sp. (Tanner Grass), Brachiaria sp. (Tanner Grass) and meal, Brachiaria decumbens Stapf and the grass Napier. The guinea pigs fed on Brachiaria sp. did not show any symptomas observed in cattle grazing on that graminea. Liver and kidney damage detected upon histological investigation on those animals were different from those observed on intoxicated cattle. The metahemoglobinemic anemia also were not detected on guinea pigs feed on Brauchiaria sp. (Tanner Grass) (1, 2, 3, 7). The urine collected from these animals showed a dark colour, this pigmentation were not found in cattle urine. The dark urine colour of cattle grazing for about one month on "Tanner Grass" was due to hemoblobinuria. The survival time of the guinea pigs feed only with B. decumbens Stapf and the grass Napier was smoller as compared with the animals receiving Brachiaria sp. (Tanner Grass). The syndrome on cattle, the effect on guinea pig added to some other aspect like the fact that plant became more toxic (2) when green and luxurious suggest a similarity with the toxic activity of some species of Brassicas such as B. oleracea var. acephala D.C., B. olerace var. capitata L. and B napus L. (5, 8).


[Ultrastructural aspects of Parthenocissus tricuspidata (Planch.) (Vitaceae) "callus" kept in solid cultures (author's transl)]. The normal strain shows undifferentiated chloroplasts in opposition to the very well chlorophyllated "callus" which shows all the normal ultrastructural characteristics of the various organelles. The strain which has lost completely the capacity of chlorophyl synthesis shows a remarkable increase in the size and number of mitochondria. The tumor tissue shows deep lobulation in its nuclei as well as undifferentiated plastids in the cytoplasm. An increase of the smooth endoplasmic reticulum in the tumor tissue was also observed.


[Contribution to the study of the haemolytic streptococci isolated from dogs (author's transl)]. The authors studied bacteriologically 740 specimens from dogs maintained at the central kennel of the Faculdade de Ciências Médicas e Biológicas de Botucatu, being the main subject the isolation of streptococci strains from the tonsilar, vaginal conjuctival and preputial secretions. Strains with the same serological properties showed a different biochemical properties, which allowed us to appoint different biochemical types inside a same serological group. On the other hand, it was also possible to detect through the precipitation capillary tube technique, the serological groups G, C, A, D and B, being the G group (73%) the most frequent one. Biochemical properties of the human G group streptococci compared with the canine G group streptococci showed a statistically significant difference in the reactions of fibrinolysis of human plasma, glicerol, sorbitol, esculin, mannitol, inulin, raffinose, salicin, trehalos, hydrolysis of the sodium hypurate, growth on 20% bile broth, and growth at 45 degrees C. The authors stress the utility of the fibrinolysis of human plasma test for the characterization of canine origin streptococci.


Virus diarrhea of the infant mice. Ultrastructure of the intestinal epithelium (author's transl). The authors studying ultrastructure of epithelium of infant mice infected with the agent of diarrhea, detected virus particles agglutinated in vesicles measuring 59 +/- 2.00 (0.988) nm. This particles had a core more dense with 30 +/- 2.00 (0.705) nm and was found in all animals studied, sick, normal or with inapparent disease.


[A bacteriological study of otitis in dogs (author's transl)]. Bacteriological examination of 100 cases of otitis in dogs revealed pure cultures of different microorganisms as follows: Staphylococcus aureus from 25 animals; Escherichia coli from 10; Proteus mirabilis from 20; Enterobacter sp. from 18 and Klepsiella sp. from 7. Mixed cultures of Proteus mirabilis, Pseudomonas aeruginosa and Klepsiella sp. were found in 3 animals; Staphylococcus aureus and Enterobacter sp. in 5; Staphylococcus aureus and Proteus mirabilis in 4. Enterobacter sp. and Klepsiella sp. in 2 and Staphylococcus aureus, Proteus mirabilis and Escherichia coli in 6. Theses results indicated that Staphylococcus aureus appeared as the most frequent microorganism (36%) followed by Proteus mirabilis (23%) and Klepsiella sp. (16%). Drug resistance studies showed that all tested strains were resistant to the antibiotics and to the nalidixic acid in levels higher than 20microgram/ml except gentamycin which showed for Pseudomonas aeruginosa a resistance level for 10microgram/ml.


Canine hepatitis virus infections in dogs of São Paulo city, Brazil. Infectious Canine Hepatitis virus was isolated from 10 of 51 tested dogs caught in São Paulo and neighbouring Districts. The viruses were isolated in dog kidney cell cultures from fecal specimens and, in two instances, from the non-inoculated cell cultures themselves. All the isolated virus strains presented biological and physicochemical characteristics proper to the adenovirus and were immunologically identified as ICH virus. Specific neutralizing antibodies to the ICH virus were found in 50% of the dogs with negative virus isolations in titers from 1/500 to 1/25,000. These results point to a very high frequency of infection by the ICH virus in the sample studied.


Androgen binding in the testis: in vitro production of androgen binding protein (ABP) by Sertoli cell cultures and measurement of nuclear bound androgen by a nuclear exchange assay. Androgen binding activity in the testis has two components. One component, ABP, has been shown to be produced by Sertoli cell cultures for at least 9 days in the absence of exogenously added hormones. FSH (10-100 microgram/ml) markedly enhances the secretion of ABP. MIX has a potentiating effect after long treatment intervals (7 days). In order to study the second component, intracellular androgen receptor, a nuclear exchange assay was developed. Competition for exchange activity using 3H-dihydrotestosterone was significant for a 500 fold excess of testosterone, dihydrotestosteron, progesterone, and cyproterone acetate. The exchange activity was increased 2-10 fold by prior treatment in vitro or in vivo with testosterone. Significant exchange activity was found in long-term hypophysectomized adult and immature animals and in tubule and germ cell fractions. In isolated germ cell fractions, the highest concentration of exchange activity was associated with the most mature elements. These data suggest that androgen exchange activity may exist in both Sertoli cell and germ cell fractions and suggest that the mechanism of action of androgens in the testis is quite complex.


Analysis of the peptide composition of purified beef-heart complex III by dodecylsulfate electrophoresis. The peptides of purified complex III from beef heart mitochondria have been studied by electrophoresis on dodecylsulfate gels. Of the 12 peptides consistently observed, only eight appear to be integral peptides of the functional complex. Attempts to identify these peptides have been made through co-electrophoresis of complex III and fractions in which the individual peptides were either purified or greatly enriched. Electrophoresis of complex III preparations which were not reduced by mercaptoethanol indicates that intermolecular disulfide bonds play no significant role in stabilizing the complex.


The specificity of a neutral deoxyribonuclease from Cancer pagurus. The recently isolated neutral deoxyribonuclease from crab (Cancer pagurus) testes has been characterized in its mode of action and its specificity. The enzyme is a typical endonuclease, forming 5'-phosphate oligonucleotides of large average size; after extensive digestion of calf thymus DNA over 75% of the fragments have a size larger than pentanucleotides and mononucleotides are absent. As far as specificity is concerned, thymidine is very abundant in the 5'-penultimate position (approximately 50%) and in the 3'-terminal position (37%) and almost absent in the 5'-terminal position (approximately 1%), the values quoted concerning Escherichia coli digests of average size (Pn) between 50 and 10.


Tryptic digestion of native small-intestinal sucrase - isomaltase complex: isolation of the sucrase subunit. Limited tryptic digestion of native sucrase - isomaltase complex produced a more rapid destruction of isomaltase activity than sucrase activity. It was possible to isolate a partially fragmented sucrase subunits in high yields with a specific activity twice that of the native complex. Amino acid and carbohydrate analyses are reported and compared with the results obtained for sucrase - isomaltase complex and isomaltase subunit obtained by a different method.


Chlorophylls attached to lipid and protein globules, absorption and fluorescence spectra, photo-oxidation. The precipitation of chlorophylls upon lipid and protein globules suspended in an aqueous buffer yields a partial model of photosynthetic membranes. The absorption and fluorescence spectra of the model are investigated as well as the photo-oxidation of the chlorophylls (bleaching) by dissolved oxygen. It is shown that pigment--pigment interactions occur in such systems, by (a) the appearance of absorption bands characteristic of crystalline or highly ordered chlorophyll at high pigment concentrations, (b) the chlorophyll a-type of fluorescence of systems containing chlorophyll a and chlorophyll b where the latter is selectively excited, and (c) the kinetics of photo-oxidation which suggest that chlorophylls can only be bleached when they are dimerized.


The amino-acid sequence of a peptide (PS-1) from Drosophila funebris: a paragonial peptide from males which reduces the receptivity of the female. The substance, PS-1, produced in the paragonial gland of adult male Drosophila funebris influences the mating behavior of virgin female flies after injection. The substance was isolated and characterized as a 27-residue peptide. The complete amino acid sequence was determined by manual sequence analysis of tryptic peptides, automated Edman degradation, and carboxypeptidase A digestion. The sequence is Asp-Val/Leu-Pro-Ser-Ala-Asn-Ala-Asn-Ala-Asn-Gln-Arg-Thr-Ala-Ala-Ala-Lys-Pro-Gln-Ala-Asn-Ala-Glu-Ala-Ser-Ser. The ratio of Val : Leu in the second position of the sequence is 7:3. This is the first detailed report on an insect peptide which causes a biological response in the opposite sex following mating.


Behaviour of tyrosyl residues of calf-thymus histone F3. Difference-spectroscopy studies. We have studied the behaviour of microenvironments containing tyrosine of calf thymus histone F3 (or histone H3) by using the difference spectroscopy techniques of thermal and solvent perturbation. By comparison of the parameters found for the models L-tyrosine methyl ester and N-acetyl-L-tyrosine ethyl ester with those for the protein at various conditions, several aspects of the tertiary structure of histone F3 become apparent. The raising of ionic strength produces a general burial of tyrosyl residues of the histone, whereas low pH or urea treatment causes a complete exposure of tyrosyl groups with respect to the solvent. Anomalously high values can also be observed of accessibility of the perturbants sucrose and ethylene glycol at low concentrations of phosphate buffer. The relevance of these findings towards a better understanding of the tertiary structure of histone F3  and of its interactions with DNA is discussed.


Complexes of metal phthalocyanines with globin as the models of heme proteins. The reaction between iron and cobalt tetrasulfonated phthalocyanines and globin results in the formation of the green complexes, as has been proved by difference spectroscopy. Spectrophotometric titration data indicate the formation of those complexes at the molar ratio 1:1. The complexes of ferrous, ferric and cobaltous tetrasulfonated phthalocyanines with globin have been isolated from the reaction mixtures by separation on Sephadex G-50 and precipitation of the protein fractions with ammonium sulfate. The visible spectra of these complexes are characterised by the main intensive peak at 641 nm, 678 nm, and 675 nm for ferric, ferrous and cobaltous derivatives, respectively. The new globin complexes have the property of reversible combination with oxygen and coordination with cyanide ions. It is evidence from the results of the spectrophotometric titrations of hemoglobin and methemoglobin with cobaltous tetrasulfonated phthalocyanine that iron protoporphyrins are displaced by this cobalt derivative; this suggests that phthalocyanine and porphyrin are bonded in a similar manner.


Studies on the role and mode of operation of the very-lysine-rich histone H1 (F1) in eukaryote chromatin. The conformation of histone H1. Proton magnetic resonance, circular dichroism and other studies of whole and cleaved calf thymus histone H1 (formerly F1) reveal the presence of specific folded structures in the region approximately from residue 40--115. Ionic, hydrogen-bond and hydrophobic interactions all appear to contribute to the stability of the structure, which is predicted to contain alpha-helices in regions 42--55 and 58--75. No evidence was found for beta-structures, either inter or intramolecular, or for any structure formation outside the region 40--115. At 18 degrees C and a protein concentration of 2 mM the first-order exchange rate between random-coil and structured forms is slower than 80 s-1; at 40 degrees C the exchange rate is faster than 330 s-1.