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Effects of phenethyl alcohol on Bacillus and Streptococcus.
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The activity of phenethyl alcohol (PEA) on Bacillus cereus, B. megaterium, and Streptococcus faecalis was studied by electron microscopy of thin sections and by the assay of intracellular K+ leakage. S. faecalis was unaffected by PEA at concentrations up to 0.5%, B. cereus was severely damaged by 0.5% PEA, and B. megaterium behaved intermediately. Important membrane ultrastructural alterations were observed in B. cereus cells treated with 0.5% PEA, namely the change in the geometry of the membrane profile from asymmetric to symmetric, the occurrence of prominent, complex mesosome-like structures, and membrane fracturing and solubilization. Protoplasts from B. megaterium were found to be quickly lysed by 0.5% PEA due to the disruption of the cytoplasmic membrane. The electron microscopic observations, together with the results of the study of the K+ efflux from B. cereus and B. megaterium, indicate that PEA primarily and directly damages the cytoplasmic membrane of sensitive bacteria. The breakdown of the permeability barrier probably is responsible for the observed bactericidal action of 0.5% PEA on B. cereus.
| 60,333
|
Lipid vesicle-cell interactions. III. Introduction of a new antigenic determinant into erythrocyte membranes.
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The introduction of a new antigenic determinant, 2,4-dinitrophenyl-aminocaproyl-phosphatidylethanolamine (DNP-Cap-PE), into the surface membranes of intact human erythrocytes is described. Fresh cells were incubated in the presence of liposomes composed of 10% DNP-Cap-PE, 5% stearylamine, 20% lysolecithin, and 65% lecithin. Such liposome-treated erythrocytes are shown to be susceptible to immune lysis by anti-DNP serum in the presence of complement. Uptake of DNP-Cap-PE by erythrocyte membranes is also demonstrated by immunofluorescence using indirect staining with rabbit anti-DNP serum followed by fluroescein-conjugated goat anti-rabbit IgG and by electron microscopy using ferritin-conjugated antibody. Antigen uptake did not occur at low temperatures or from vesicles lacking lysolecithin and stearylamine. Fluorescence microscopy shows that the antigen-antibody complexes are free to diffuse over the cell surface, eventually coalescing into a single area on the cell membrane. Electron microscopy suggests that a substantial proportion of the lipid antigen is incorporated by fusion of vesicles with the cell membrane. There are indications that vesicle treatment causes a small proportion of cells to invaginate.
| 60,342
|
Mobility restriction in vivo of the heavy ribosomal subunit in a secretory cell.
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Analysis in insect (Chironomus tentans) salivary gland cells of labeled RNA as a function of time after precursor injection and its distance to the nuclear membrane, cytoplasmic zone analysis, could previously be used to demonstrate the presence of short-lasting gradients in newly labeled ribosomal RNA. Since the gradients were sensitive to puromycin, they are likely to be a result of diffusion restriction due to an engagement of the subunits into polysomes. In the present paper the possibility was explored of recording gradients that were caused by labeled subunits in puromycin-resistant associations, which, in all probability, involve the endoplasmic reticulum. It was found that labeled 28 S and 5 S RNA but not 18 S RNA were present in radioactivity gradients lasting for at least 2 days but less than 6 days. The gradients also remained during inhibition of RNA synthesis by actinomycin, and they were completely resistant to puromycin whether given in vivo or in vitro. The semipermanent gradients formed fhere offer a unique parameter for the in vivo study of conditions for formation and maintenance of heavy subunits in puromycin-resistant bonds. An explanation for these and previous results is that the light subunit, although restricted in movement by engagement to polysomes, is nevertheless free to exchange and spread between rounds of translation, whereas at least part of the heavy subunit population is bound to the endoplasmic reticulum and less free to spread. These results offer a good in vivo correlate to previous results on in vitro exchangeability of subunits.
| 60,343
|
Single-strand nuclease action on heat-denatured spermiogenic chromatin.
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The aim of this study was to compare the sensitivity of chromatin from representative cellular stages of spermiogenesis to a single-strandeded nuclease after heat denaturation. Thermal denaturation of chromatin was assayed in situ in fixed round, elongating and elongated spermatids and in testicular sperm from mice. Production of single-stranded deoxyribonucleic acid (DNA) at elevated temperatures was monitored by digesting chromatin with endonuclease specific for single-stranded DNA (S1 nuclease), staining the residual DNA with gallocyanin-chrome alum (GAC) and measuring the stain content by absorption cytophotometry. Changes in GCA staining were minimal over the temperature range of 22-90 degrees C in each cell type not exposed to nuclease. Staining of undigested cells decreased progressively with advancing cell maturity. Nuclease had no effect on the GCA content of round spermatids below 60 degrees C, but above this temperature there was a progressive decrease in GCA-stainable chromatin. Both round and elongating spermatid stages showed a significantly greater sensitivity to nuclease digestion than did more mature stages; sperm showed no effects of nuclease action below 80 degrees C. Progressive chromatin condensation and a concomitant decrease in the number of available DNA phosphate groups during spermiogenic cell maturation may be responsible for the observed decline in sensitivity to nuclease and decreased GCA staining. Thermal denaturation of round spermatids labeled with 3H-thymidine produced no change in autoradiographic mean nuclear grain counts, indicating no loss of thymidine-labeled DNA from the slides during denaturation. When round spermatids and sperm were hydrolyzed with hot tricholoroacetic acid before staining, both nuclear GCA content and autoradiograph grain count were partially reduced, indicating incomplete DNA removal. Almost complete loss of Feulgen-stainable material occurred in these cells and may be due to depurination and elimination of Feulgren-reactant aldehyde groups.
| 60,438
|
Immune complex receptors on cell surface. I. Ultrastructural demonstration of macrophages.
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A method is described for ultrastructural localization of immune complex receptors on the surface of viable peritoneal exudate cells. The technique entails incubation with a soluble complex of horseradish peroxidase (HRP) and specific antibody to HRP at 4 degrees C followed by exposure to diaminobenzidine and processing for electron microscopy. The bound immune complexes were evident as focal deposits of HRP reaction product, adhering closely to the external surface of macrophages with an uninterrupted periodicity varying between 30 and 120 nm. Following incubation with an insoluble immune complex containing a higher proportion of antibody, receptor sites stained frequently, but large aggregates adhered to the cells. Rinsing cells after staining with soluble complexes partially displaced the bound immune complexes. Fixation prior to exposure to immune complexes largely eliminated the binding capacity of the immune complex receptors.
| 60,441
|
Synthetic glycolipid adjuvants.
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In the course of the organic synthesis of model compounds similar in some features to the lipid moiety of endotoxic lipopolysaccharide (LPS), Nacylated-D-glucosamine derivatives were prepared. One of these, N-palmitoyl-D-glucosamine, has been previously found to be mitogenic for athymic nude mouse B cells. This and other N-acylated homologs were tested for adjuvant activity in the immune response to human gamma-globulin (HGG) and sheep red blood cells (SRBC) in mice. Comparable or superior enhancement of the immune response was obtained for these glycolipids when compared to LPS in assays measuring anti-SRBC or HGG hemagglutinin titers. In the determination of hemolytic plaque formation, considerable adjuvant effect was shown by the lauroyl derivative, and less but still significant enhancement was achieved by the N-palmitoyl-D-glucosamine. In the rosette formation assay, in addition to the above two glycolipids, N-oleyl-D-glucosamine showed good adjuvant effect. In the latter two assays, the LPS was a superior adjuvant as compared to the synthetic glycolipids. The radiation protective effect of some of the better synthetic adjuvants was also investigated in mice. It was found that although LPS was more effective in this assay, the N-myristoyl-D-glucosamine and N-decanoyl-D-glucosamine compounds gave a definite protection, since up to 40% of the lethally irradiated (700 R) mice survived.
| 60,450
|
Cellular events in the induction of experimental allergic encephalomyelitis in rats.
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Although both the T and B cells of the Lewis rat have immunoglobulin receptors for basic protein (BP) of myelin, and both cell types are required for antibody production to BP, the present results demonstrate that the T cells are the only cells required for the induction of experimental allergic encephalomyelitis (EAE). Both EAE and anti-BP were readily induced in thymectomized, irradiated Lewis rats reconstituted with normal thymus and bone marrow cells and challenged with BP in complete Freund's adjuvant. If the thymus cells were first treated with BP heavily labeled with 125I so as to eliminate (sucide) specific T cells, the recipients neither develop EAE nor produce antibody to BP. On the other hand, if the thymus cells were untreated and the specific B cells of bone marrow were eliminated by treatment with 125I-BP, EAE was not inhibited, although no antibody was produced. These results strongly suggest that the T cell is responsible for the induction of EAE although both the T and B cells are competent to respond to BP. Evidence was presented which suggests that neither suppressor T cells nor circulating antibody are involved in the inhibition of EAE by injection of Lewis rats with nonencephalitogenic preparations of BP. The immune status of T and B cells of the Lewis rat to BP was compared with the immune status of these cells in other species to thyroglobulin, where only the B cells appear to be competent. In this context, Brown Norway rats, which are resistant to the induction of EAE, also appear to lack T cells reactive to BP, although competent B cells are present.
| 60,461
|
Some chemical principles applicable to some silver and gold staining methods for neuropathological studies.
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Some of the chemical principles involved in some silver and gold staining procedures for neuropathological studies are analyzed in the light of experience with methods for astrocytes, microglia, axons and reticulin fibers. The role of formalin fixation, and of treatment with ammonium bromide or oxidizing agents prior to staining for glial cells or reticulin fibers respectively, is described. The silver staining methods are divided into two fundamentally different groups. One is based on the use of silver diammine solutions with or without other substances such as carbonates or pyridine, and at varying times, gold toning. This group encompasses a great variety of techniques for staining glial cells, reticulin fibers and axons. The second group is based on the use of weak solutions of silver ions, reduction in a photographic developer, treatment with gold chloride, and a second reduction in oxalic acid. This group is represented by methods for staining axons and reticulin fibers. A brief analysis of the gold and mercuric chloride methods for astrocytes is also given.
| 60,469
|
Vinyl acetate casts of emphysematous rat lungs.
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Emphysema was induced in rats by chronic exposure to a papain aerosol according to established methods. The emphysematous changes were evaluated by previously described histological and biochemical parameters and by a new method employing infiltration of the lungs with vinyl acetate to make casts of the air spaces of the pulmonary tree. The weights and gross and microscopic appearance of the casts demonstrated the emphysematous changes in lungs of the papain-treated rats. Vinyl acetate casting may offer a new and useful tool in evaluating experimental induction of emphysema in rats.
| 60,483
|
Alterations in amounts and rates of serotonin transported in an axon of the giant cerebral neurone of Aplysia californica.
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1. The giant cerebral neurone of the sea hare, Aplysia californica, is a unipolar serotonergic cell. Its axon bifurcates, one branch travelling in the cerebrobuccal connective, the other in the posterior lip nerve. 2. I13H]serotonin was injected under pressure into the cell body of the giant cerebral neurone. We studied fast axonal transport of the radioactive transmitter substance along the lip nerve when the cerebrobuccal connective was cut close to the bifurcation. 3. When the connective was cut, more than twice as much [3H]serotonin was transported along the lip nerve compared to uncut control nervous systems. 4. The increased [3H]serotonin appearing in the nerve probably was originally destined to enter the connective, but was diverted from the cut stump which was occluded with backed-up material. 5. The incremental [3H]serotonin in the lip nerve was not the result of increased export from the soma in response to injury. 6. Not only was more [3H]serotonin transported along the lip nerve, but also a far greater fraction of the transmitter moved at very fast transport rates, approaching 120 mm/day. In uncut control nerves only a small fraction of total [3H]serotin moved faster than 70 mm/day. 7. These results are interpreted with a model for fast axonal transport. We suggest that serotonergic vesicles move at a fixed, maximal speed when attached to essentially immobile tracks, but that the vesicles are only intermittently associated with the tracks. We presume that the rate-limiting step in movement of vesicles is the concentration-dependent and reversible binding to the tracks. Transport along axons may be considered analogous to those enzymatic reactions in which formation of the enzyme-substrate complex limits the appearance of product. Translocation is here analogous to formation of product. The process may therefore be approached theoretically by modification of the Michaelis-Menten formulation.
| 60,486
|
Type C viruses from Kirsten sarcoma-transformed mink cells co-cultivated with primate cells and expressing p30 antigens related to feline leukemia virus.
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Two type C viruses with new antigenic and biological properties were isolated by co-cultivating secondary cell strains established from the kidneys of a baboon (Papio papio) and a patas monkey (Erythrocebus patas) with mink cells non-productively transformed by Kirsten sarcoma virus. Both new isolates (designated PP-1R and EP-1R) contain major structural proteins (p30) that are immunologically most closely related to the p30 proteins of feline leukemia viruses. The reverse transcriptases of both viruses, although antigenically related to polymerases of murine and rat type C viruses, are distinct from those of previously described type C viral groups. Both PP-1R and EP-1R can be transmitted to canine and feline cells and to sarcoma virus-transformed, but not normal, mink cells. Both viruses contain RNA genomes partially homologous to those of endogenous mouse and rat type C viruses and the Kirsten sarcoma virus. In addition, the RNA of PP-1R contains a portion of the nucleic acid sequences found in a type C virus isolated from the baboon species P. papio. We propose that both new isolates are genetic recombinants formed between endogenous primate type C viral genomes and sequences found in Kirsten sarcoma-transformed mink cells.
| 60,495
|
Administration of human fibroblast interferon in chronic hepatitis-B infection.
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One patient with hepatitis-B surface antigen (HBsAg)-positive chronic aggressive hepatitis, and two chimpanzee carriers of HBsAg, were each given seven doses of 10(7) I.U. of human fibroblast interferon over two weeks. The main differnce observed after treatment was a depression of the nucleocapsid hepatitis-0 core antigen in the liver, indicating that hepatitis-B virus infection is sensitive to interferon. Except for a short febrile reaction, no undesirable effects were seen after the administration of human fibroblast interferon which has not been previously given to man.
| 60,513
|
Effects of timolol and hydrochlorothiazide on blood-pressure and plasma renin activity. Double-blind factorial trial.
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The effects of timolol (10 mg thrice daily) and hydrochlorothiazide (50 mg/day) have been compared in a double-blind factorial trial in 20 patients with essential hypertension. There were four randomised test phases of 8 weeks each during which patients received timolol alone, hydrochlorothiazide alone, timolol plus hydrochlorothiazide, and no treatment (placebo). Blood-pressure was measured weekly, alternately at the outpatient clinic and at the patient's home. Supine mean arterial pressure fell from 119 mm Hg in the placebo phase to 110 mm Hg in the hydrochlorothiazide phase, 106 mm Hg in the timolol phase, and 101 mm Hg in the combined timolol plus hydrochlorothiazide phase. Factorial analysis revealed that these effects of the two drugs were additive without any potentiation or antagonism. Mean plasma-renin activity (P.R.A.) was 5-02 ng/ml/3 h in the placebo phase falling to 1-79 in the timolol phase and rising to 9-54 in the diuretic phase, but remaining unchanged in the combined treatment phase (5-40 ng/ml/3 h). The data suggest that the hypotensive action of timolol is not dependent on the concomitant fall in P.R.A. The methods described provide a valuable tool for quantitating the effects of a given drug, and hence a valid basis for objective comparison.
| 60,566
|
[Hepatitis: an international problem (author's transl)].
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Three kinds of virus hepatitis are recognized today: hepatitis A, B, and "non A-nonB". Hepatitis A is transmitted mainly by the anal-oral route, hepatitis B and probably also the third form of hepatitis principally by direct inoculation or close physical contact. Normal human immune serum globulin protects against hepatitis A, but only gives limited protection against hepatitis B and "non A-non B" hepatitis. Special immune serum globulin provides better protection but it is only available in small quantities and should be reserved for direct inoculation only. Vaccines for active immunization against hepatitis A and "non A- non B" hepatitis have not yet been developed and active immunization against hepatitis B with HBs-Ag is still in the experimental stage.
| 60,698
|
[Incidence of viral hepatitis in travelers in the tropics. Experiences with gamma globulin prophylaxis (author's transl)].
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The occurrence of virus hepatitis during their residence was determined in 2755 persons returning from the tropics in 1975. The incidence was particularly high in those returning from India, Pakistan and Afghanistan. There was also a greater risk of the disease for travelers in Ethiopia, the countries on the West coast of Africa and some South American States. On the average, persons returning form the tropics fell ill 10 times more frequently with virus hepatitis during their residence in the tropics than in the Federal Republic. Particularly endangered occupational groups were the staffs of the health services and the social workers. Immunization with gamma globulins prevented an attack of virus hepatitis in all cases for a period of 4-6 months. Later, the effect of the immunization could no longer be established.
| 60,699
|
The development of the blood-CSF barrier after birth.
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The serum/CSF concentration ratio of alpha-2-macroglobulin is used as parameter to follow the development of the blood-CSF barrier throughout childhood. The decline of the protein permeability within the first year of life has all characteristics of a maturation process. The tightening of the barrier is thought to be the last stage of a continuous developmental process of capillaries. It is accompanied by a compositional shift in favour of small molecular serum proteins.
| 60,727
|
Social learning approaches to health education: utilization of infant auto restraint devices.
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There has been little critical evaluation of which methods achieve the desired results in health education. Using purchase of proper infant auto restraint devices as an objective, we assessed the effectiveness of three educational approaches. Only 37% of control families had purchased an acceptable car seat, compared to 54% of those who received descriptive literature alone, 71% of those that received literature and had been shown a descriptive film, and 60% of those who were given literature, shown the film, and been provided with a demonstration of the seat. Purchase of car seats was positively correlated with social class and knowledge of auto safety, but not with a history of auto accidents. Utilization of auto restraint devices is an example of how social learning theory can be applied in health education.
| 60,736
|
An evaluation of a procedure for the isolation of myelin basic protein (BP).
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A detailed description and stepwise evaluation of a procedure that can be used to obtain myelin basic protein (BP) from whole brain is presented. The procedure involved the 0.001 MHC1 extraction of whole brain pre-treated in a sequential manner with chloroform-methanol (2:1 v/v), acetone, and deionized water. This is followed by a precipitation of the extract at pH 9.0, and gel filtration of the supernatant in 0.01 M HC1. Yields of canine and porcine BP and their disc gel evaluations are presented at several key points in the procedure. The final products possessed a high degree of homogeneity when examined on SDS gels stained with commonly used protein stains. When compared with six SDS-gel marker-protein standards, the canine and porcine final products had mobilities that correspond to an apparent molecular weight of 18,5000 +/- 5%. Quantitative binding of 125I-labeled canine and porcine BPs with standardized rabbit anti-BP antisera gave comparable results. Immunoelectrophoretic and immunodiffusion examinations demonstrated single components and complete identity. The canine and porcine BP's also reacted fully with syngeneic anti-BP antisera raised in Lewis-strain rats. The canine BP was tested for encephalitogenicity in Lewis-strain rats and found to be comparable to rat BP in producing experimental allergic encephalomyelitis.
| 60,758
|
Prenatal detection of anencephaly.
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Fetal anomalies were suspected clinically in 3 patients, during the second trimester of pregnancy, due to advanced maternal age, hydramnios and abnormal vaginal bleeding respectively. Sonography revealed anencephaly in all of them, confirmed by roentgenograms and also by high amniotic fluid leveal alpha-fetoprotein in 1 of them. The antenatal diagnosis was confirmed in the 3 abortuses. Early screening of all pregnancies at risk for neural tube malformations is strongly recommended.
| 60,775
|
HLA and juvenile chronic polyarthritis.
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HLA antigen have been identified in patients with juvenile chronic polyarthritis (J.C.P.) (n = 35). In J.C.P. the incidence of antigen B27 (57%) was found to be higher than in a normal population (n = 1,000). On recent evaluation of the clinical status, serology and x-rays, the patients with juvenile chronic polyarthritis who has been followed up many years, could be subdivided into four groups: Group 1: J.C.P. evolving to ankylosing spondylitis (n = 3); Group 2: J.C.P. with sacroiliitis (n = 17); Group 3: J.C.P. without sacroiliitis (n = 9); Group 4: juvenile rheumatoid arthritis characterised by a positive serology (n = 6). Groups 1 and 2 were characterized by a high incidence of antigen B27 (19/20). Only one subject of groups 3 and 4 had antigen B27. Sex distribution in groups 1 and 2 was found to be similar to that found in ankylosing spondylitis in adults and sex distribution in groups 3 and 4 was found to be similar to that found in rheumatoid arthritis in adults. It is concluded that if B27 positive develop juvenile chronic polyarthritis they have a high risk of developing sacroiliitis and acute uveitis. The authors propose to give the name Still's disease to the total group of children presenting initial symptoms corresponding to the criteria of Ansell & Bywaters (1959). Follow-up of the cases permitted their further classification as juvenile ankylosing spondylitis, as juvenile chronic polyarthritis with or without sacroiliitis or as juvenile rheumatoid arthritis.
| 60,796
|
[Antigenic analysis and immunological studies of the uterotropic bacterial strains SH6 and 01 isolated from aborted cows].
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The uterotropic strains SH6 and O1 were studied immunoelectrophoretically to establish their antigenic relationship. The more readily diffusing component of the O-antigenic fraction of the strains proved immunologically identical with LPA of the R Brucella organisms, while the slower component showed common determinants with the O-antigenic fraction of Yersinia pseudotuberculosis. Immunodiffusion revealed that the O-antigenic fraction of the O1 strain and LPA of the S Brucella organisms contained common antigenic determinants having a weak immunologic activity, and this could explain the agglutination reaction after Wright and Huddleson of the sera from cows with infections caused by the uterotropic strains described. It was established through electrophoresis that in contrast to Yersinia enterocolitica 373 the O-antigenic fraction of the uterotropic strains is immunologically identical with LPA of the R Brucellae. An analogy is shown to exist between the immunologic activity of cow sera from infected animals and the A substance as well as at higher agglutination titers after wright of substance B as described by Amarasinghe.
| 60,821
|
Cell-mediated immunity in lumphocytic choriomeningitis. I. The specificity of the cytotoxic T lymphocytes.
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The specificity of cytotoxic T lymphocytes (CTL) generated during murine lymphocytic choriomeningitis (LCM) has been investigated. CTL were obtained from the spleens of mice injected i.p. with LCM virus. The cytotoxic activity of the CTL was tested in an in vitro 51Cr cytotoxicity assay using infected macrophages or fibroblasts as target cells. At the peak of the cytotoxic T cell response (7-8 days after infection) the cytotoxic action was restricted to syngeneic virus-infected target cells. Using H-2 recombinant mice the target antigen of the CTL generated could be identified as products coded for by either the H-2 K or H-2 D region of the major histocompatibility complex. I region identity between CTL and infected target cells was insufficient for optimal lysis to occur. During the early phase of LCM virus infection there was a transient phase during which non-infected H-2 histocompatible targets were lysed as efficiently as virus-infected target cells. This finding may suggest, that during the early phase of LCM disease self-reactive cytotoxic T lymphocytes are temporarily present in LCM virus-infected mice.
| 60,840
|
Mixed leukocyte reaction in rats. Effect of immunization with bovine encephalitogenic protein and Freund's complete adjuvant.
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Rats of certain strains immunized with bovine encephalitogenic protein (EP) in Freund's complete adjuvant develop an impairment of the mixed leukocyte reaction (MLR) similar to that seen in rabbits with experimental autoimmune encephalomyelitis and in humans with certain diseases, including multiple sclerosis. The rats mount a cell-bound response to EP, but encephalomyelitis does not develop. The component causing the impairment was analysed in a culture system using inbred rat strains and F1 hybrids, thoracic duct cells as a source of lymphocytes, and blood as a supplement to the cultures. In normal rats, it was shown that the effects of responding and of stimulating lymphocytes could be separated and that the supportive action of the added blood was probably due to macrophages (monocytes); also that the added blood could in many experiments be replaced with 2-mercaptoethanol (2-ME). The impairment present in immunized rats is at least largely due to a defective supportive activity of the blood (monocytes) and can be restored with 2-ME. The results argue that the MLR impairment seen in immunized rats is due to a faulty macrophage function.
| 60,845
|
[Effectiveness of specific treatment of rabies. II. Analysis of cases of human death from rabies following a complete course of treatment with specific agents].
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Of 79318 persons treated of rabies in the Uzbek SSR in 1968--1974 there were recorded 16 cases of death of clinically manifest rabies. The course of treatment included injection of rabies gamma-globulin in a dose of 0.5 ml per 1 kg of body weight and the maximal dose of rabies vaccine. The incubation period lasted from 44 to 833 days (229.6 on the average). The authors considered that irrational use of high doses of rabies preparations was the cause of unsuccessful treatment of rabies.
| 60,857
|
[Isoelectric spectra of hepatitis B antigen antibodies to it].
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Isoelectric focussing in a stable pH-gradient of ampholines, serum and fraction 4-4, containing hepatitis B antigen demonstrated that the antigen occupied the pI 4.31--6.03 zone with the maximum activity at pI 4.31--5.56. The activity of antibodies to the hepatitis B antigen was revealed in a donor serum and in the gamma-globulin fraction in the pI 7.76--8.4 zone with the activity maximum at pI 8.03--8.23. It was demonstrated immunochemically that antibodies against hepatitis B antigen belonged to immunoglobulin G.
| 60,859
|
[Neurotropic activity of the gamma-globulin fraction in the serum of schizophrenic patients].
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The report is concerned with the influence of the blood sera of schizophrenic patients on the electric activity of neurons in snails and its 3 fractions containing respectively nonprotein compounds, gamma-globulins and the remaining proteins. It was established that the amount of neurotropic activity only of gamma-globulin fractions do not differ significantly from the respective figures of the blood sera of schizophrenic patients. In this connection the authors come to the conclusion of a possible immune nature of the neurotropic factor in the blood sera of schizophrenic patients.
| 60,860
|
Cytology of serous effusions: a comparative study of two slightly different preparative methods.
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A prospective study of 100 serous effusions was made by two slightly different technics of smearing cells from the centrifuged sediment onto glass slides. Those made with the cotton swab had greater cell concentration and better cell morphology than matching slides prepared by the pipette-"hematologic" two-slide technic. Exclusive use of the cotton swab, therefore, is recommended in making these preparations. On follow-up, in this series of 72 patients, there was a false positive rate of zero per cent, and a false negative rate of 29%.
| 60,862
|
Statistical analysis of the different factors which could affect postextrasystolic potentiation in the human heart.
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The effect of different coupling indices and intervals that could theoretically affect postextrasystolic potentiation has been investigated. A total of 150 ventricular premature beats corresponding to 20 patients submitted to routine cardiac catheterization were studied. Only single ventricular premature contractions following at least four regular sinus beats were considered. Percentage changes in left ventricular systolic pressure, end-diastolic pressure, and max dp/dt were correlated against seven indices and intervals. Index 2 (coupling interval/coupling interval + postextrasystolic pause) gave the better correlations. Besides, this Index includes two intervals that were demonstrated to have statistical significance when individually considered. It has been proved that in the first postextrasystolic beat the highest values of max dt/dt, or left ventricular systolic pressure occurred in early ventricular premature beats, giving a negative regression with Index 2, while in the second postextrasystolic beat the highest values of max dp/dt and left ventricular systolic pressure corresponded to late prematuring beats, giving therefore positive regressions with Index 2 (slope inversion phenomenon). The third and fourth postextrasystolic beats had similar positive regressions but with progressively smaller slopes. Correlations between left ventricular end-diastolic pressure and Index 2 were very poor. It is suggested that variations in baroreceptor activity could account for the different forms of potentiation observed in early and late extrasystoles. In five cases, there were no consistent differences in potentiation when premature beats were elicited from either right or left ventricles.
| 60,878
|
Protease inhibitors in plasma of patients with chronic urticaria.
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The hypothesis that deficiencies of plasma protease inhibitors might play a role in the pathogenesis of chronic urticaria was evaluated. Plasma levels were measured in patients with urticaria and a matched control group for alpha1-antitrypsin, alpha2-macroglobulin, total trypsin-inhibiting capacity, kallikrein-inhibiting capacity, and the complement factors C1 esterase inhibitor, C3, and C4. A total of 92 patients with chronic urticaria or more than three months' duration was studied. Patients with acquired cold urticaria had significantly decreased levels of alpha1-antitrypsin and total antitrypsin activity. In patients with acquired angioneurotic edema, alpha1-antitrypsin levels and antichymotrypsin activities were lowered, with less significant decreases in anti-trypsin and antikallikrein activities. Levels of C1 esterase inhibitor , C3, and C4 were normal in all groups. There was no correlation between the increased sensitivity to intracutaneously administered kallikrein injection and deficiencies of of protease inhibitors.
| 60,915
|
Chemosurgery for skin cancer: fixed tissue and fresh tissue techniques.
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Complete microscopical control of the excision of cancer of the skin is achieved by removing tissues layer by layer and examining the undersurface of each layer by means of frozen sections. If the cancer is extensive and complicated or if it is of a type readily spread over an excisional surface, the tissues are fixed in situ with zinc chloride prior to excision (chemosurgery, fixed tissue technique). If the cancer is not too extensive or complicated, the tissues are excised in the fresh, unfixed state (chemosurgery, fresh tissue technique). Both techniques are highly reliable; for example, in two consecutive series of basal cell carcinomas treated chemosurgically, the five-year rate of cure was 99.3% for the 9,351 lesions removed by the fixed tissue technique and 97% for the 127 lesions removed by the fresh tissue technique.
| 60,916
|
Lipoprotein lipase in the fat body of Triatoma brasiliensis.
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Lipoprotein lipase activity was detected and characterized in the fat body of Triatoma brasiliensis one of the vector of Chagas' disease. The enzyme activity was close to a free fatty acid production of 47 mumol FFA mg protein-1-h-1 when assayed in the complete system. 2. The enzyme presented maximum activity at pH 8.5. It appeared to be activated by heparin (2 U/ml) and to require a cofactor (rat serum lipoproteins) when assayed with simple triglyceride emulsions. The requirement for a FFA acceptor (albumin or CaCl2) was also observed. 3. Inhibition of enzyme activity by pyrophosphate, HDB, protamine sulphate and 1 m NaC1 indicated further that the enzyme from fat body of T. brasiliensis had the characteristic features of lipoprotein lipase from other sources.
| 60,918
|
Effect of certain organic compounds on saliva secretion in sheep.
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In two sheep fitted with esophageal cannulas the stimulation of resting saliva secretion by intrabuccal injections of volatile fatty acids (VFA) and of certain organic plant compounds was investigated. Volatile fatty acids, salicin and vanillin increased saliva flow rate by 100, 76 and 72% over 2.5 min after injection. Minor positive or negative effects were obtained with quercitrin, protocatechuic acid, grass juice, anethole and agaricinic acid. Injections of volatile fatty acids and of salicin induced chewing activities, which were significantly correlated with salivary flow rates. The results indicate that organic plant compounds can provide a stimulus for saliva secretion mediated in part by chewing activities.
| 60,921
|
Susceptibility to insecticides of Lasioderma serricorne (F.) (Coleoptera anobiidae) grown on vitamin-deficient diets.
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Variations in the susceptibility to pyrethrum and chlordane (two contact insecticides) of Lasioderma serricorne grown on different vitamin-deficient diets were studied and reasons for such variation were proposed.
| 60,974
|
[Effect of curarization on sensitivity of chicken latissimus dorsi to electric current].
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(1.) To test the sensitivity to electric current of the latissimus dorsi and, therefore, its ability to yield action potential, we have studied the effect of curarisation on the amplitude of the isometric tetanus during "massive" stimulations by alternative current. (2.) Curarisation causes a considerable but reversible reduction of the tetanic tension of the latissimus dorsi anterior (L.D.A.) but has no effect on the tetanus of the latissimus dorsi posterior (L.D.P.). It is concluded that a part of the L.D.A. is not sensitive to electric current and is thus unable to yield action potentials, unlike the opinion of some authors. (3.) Rising the temperature has an inverse effect on the speed of the tetanus ascending phase, depending on whether the L.D.A. has been curarised or not. This show the existence of two types of excitation processes of very different nature in this muscle. (4.) Direct current is much less efficient than alternative current on the curarised L.D.A.
| 60,976
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Post-tetanic changes of depressor responses evoked by stimulation of the aortic nerve.
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The effect of changes in duration of the conditioning tetanus on the size of the testing depressor response was studied in rabbits anaesthetized with urethane. Depressor responses were evoked by stimulation of the aortic nerve. The interval between the conditioning and testing stimulation was fixed at 40 and 120 sec. Two frequencies of conditioning tetanus were employed. Brief conditioning tetani facilitate the testing response. With lengthening of the conditioning stimulation the size of the testing response is decreased and when duration of the conditioning amounts to 20-60 sec depression of the testing fall of blood pressure reaches a steady level. Further increase in duration of the conditioning tetanus to 180 sec does not affect the plateau of depression of the testing response. The longest duration of conditioning affecting the size of the testing response is considered to determine the range of control of the testing response exerted by preceding conditioning tetanus. Since the levels of plateau of depression are different for two used frequencies of conditioning, it is suggested that this factor may control the size of the testing response beyond the range of control executed by the duration of the conditioning tetanus.
| 60,979
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[Morphological studies on cellfree induced sarcomas in syrian hamster (author's transl)].
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Morphological studies on sarcomas induced in syrian hamsters by cellfree transmission are described. The tumour tissue for the cellfree preparations stemmed from a sarcoma, containing C-particles. Basically, three histological groups have been distinguished: 1. neoplasms of the peripheral nerve-sheath, 2. undifferentiated sarcomas, and 3. liposarcomas. Furthermore, a rhabdomyosarcoma, an angiosarcoma and, in a heterotransfection on rat, an osteosarcoma have been established. The great majority of tumours could be transmitted by cellfree preparations. To this neoplasms belong the undifferentiated histological structure.
| 60,983
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The similarity of changes in segmental contraction patterns induced by postextrasystolic potentiation and nitroglycerin.
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Despite a fundamental difference in their underlying mechanisms, both postextrasystolic potentiation (PESP) and administration of nitroglycerin (TNG) have been utilized to predict reversibility of abnormal segmental wall motion in patients with ischemic heart disease. To determine whether these interventions induce the same changes in segmental contraction pattern, we analyzed biplane ventriculograms of 14 patients who had an adequately visualized PESP beat on a basal ventriculogram as well as a post-TNG ventriculogram. Four segments in each plane were defined and the area ejection fraction of each segment was calculated for a basal sinus, PESP, and post-TNG beat. To correct for global differences in the response to PESP and TNG, we normalized each segmental ejection fraction (NSEF) by the ventricular ejection fraction for that beat and then compared the differences in NSEF from the basal value after PESP and TNG. Eleven patients demonstrated similar responses to both interventions. The three patients whose responses were discordant had elevated or unchanged left ventricular systolic or end-diastolic pressures at the time of the TNG ventriculogram. Our data suggest that, provided these pressures are lower than basal values at the time of the TNG ventriculogram, PESP and TNG will induce similar changes in segmental contraction patterns. Seven patients with similar responses had a PESP beat on their post-TNG ventriculogram. Changes in NSEF after PESP+TNG were identical to those after either intervention. This implies that the combination of interventions does not induce further changes in segmental contraction pattern beyond that produced by either intervention alone.
| 61,073
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Serum cholesterol and bile acid in primary hepatoma.
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The close relationship between serum levels of cholesterol and bile acid has been confirmed in 46 patients with primary hepatoma. Serum levels of cholesterol and bile acid are roughly correlated with serum alpha-fetoprotein concentration. Because the relationship between serum cholesterol and bile acid did not exist in common hepatocellular diseases, the results suggest a peculiar sterol metabolism occurring in human hepatoma.
| 61,074
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The length of parallel fibers in the cat cerebellar cortex. An experimental light and electron microscopic study.
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Experimental light and electron microscopic studies were carried out to determine the length of parallel fibers in the cat cerebellar cortex. Using a fine surgical knife, vermal and hemispheral folia were cut perpendicular to their long axis. The animals were sacrificed 1-10 days after the operation. Sections of the transected folia were then stained with a Fink-Heimer procedure. The resulting degeneration appeared as fine dots that extended lateral to the lesion, as predictable from the course of the parallel fibers. Densitometer readings indicate that the density of degeneration declines gradually lateral to the lesion. The specificity of the silver impregnation was checked by processing silver stained sections for electron microscopy. This confirmed the location of the silver precipitate on degenerating parallel fibers. The pattern of parallel fiber degeneration in the molecular layer has a trapezoidal configuration centered on the lesion. The shorter parallel fibers are located at the base of the molecular layer and extend for 5 mm. The parallel fibers become progressively longer as they approach the pial surface where they attain a maximum length of 7 mm. Our studies suggest that in folia longer than 7 mm parallel fibers are 6 mm long on the average. In addition, it was determined on Golgi sections that the average center-to-center distance between en passant boutons of individual parallel fibers is 5.2 mum. The data indicate that an average parallel fiber, 6 mm long, forming approximately 1100 boutons, may synapse with each Purkinje dendritic tree it traverses.
| 61,126
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Correlation of light and electron micrographs of human metaphase chromosomes after incorporation of BUdR and staining with "33258 Hoechst" and Giemsa.
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Stained (Giemsa, "33258 Hoechst"1) and "33258 Hoechst" + Giemsa) and unstained metaphase chromosomes from human peripheral lymphocytes, after two rounds of replication in the presence of 5-bromodeoxyuridine (BUdR), have been prepared for electron microscopy. There is a positive correlation between light and electron micrographs. The same differential contrast on electron micrographs has been obtained whether the preparations have been stained or not. We attribute this differential contrast primarily to the lesser condensation of the bifilarly substituted chromatid.
| 61,129
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Effects of the liver homogenate obtained following partial hepatectomy on cirrhosis of the liver.
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The authors studied the influence of liver homogenates as a whole and collected at various intervals after partial hepatectomy on cirrhosis of the liver. The lyophilized homogenates were administered over a period of 6 weeks to various groups of albino rats pretreated with CCl4 for a period of 6 months. The normal liver homogenate did not influence the histological and biochemical picture of the hepatocirrhosis. The material collected 48 hours after partial hepatectomy causes a moderate stimulation of the mechanisms of parenchymatous regeneration. 7 days after partial hepatectomy (in the postmitotic period) the hepatic regenerate shows a biological effect with lysis of collagen fibres and protection of parenchymatous cells.
| 61,133
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The chemical structure of capreomycin.
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The chemical structure of capreomycin, antituberculous peptide antibiotic, was revised from the results of NMR-analysis in comparison with tuberactinomycins. Capreomycin IA and IB were concluded to possess the similar amino acid sequences in their cyclic peptide moieties to those of tuberactinomycins.
| 61,134
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[Rhinosporidiosis: clinical aspects, epidemiology and ultrastructural studies on Rhinosporidium seeberi].
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The author revises the main clinical aspect of the disease as well as its dignosis and its treatment. Rhinosporidium seeberi, first described by J.R. Seeber in 1900, then exhaustively investigated by J.H. Ashworth in 1923, has been accepted up to now as a phycomycete. Inside of the sporangial bodies, part of the polyp characteristic of the disease, are found spores, and in the spores, spherules, considered by Ashworth as food material. In 1955 the author did challenge the view of Ashworth because he had been able with the Feulgen stain to demonstrate the presence of DNA attached to the spherules. The results obtained by Vanbreuseghem were confirmed in 1964 by W.A.E Karunaratne and R. Cameron and Dorothy Russel. They were later confirmed in India by Lakshmanan. In an effort to understand better the real nature of Rhinosporidium seeberi which so far has never been successfully cultivated or inoculated in any animal, a study with the ultramicroscope has been done. Although it is difficult from the results obtained so far to decide of the real nature of R. seeberi, no proof has been found to confirm the theory of Ashworth. Quite evidently much has to be done to decide of the real nature of this interesting parasite.
| 61,137
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[New aspects and methods in gastroenterological diagnosis].
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Advances in the diagnosis of gastrointestinal diseases are achieved by development of new methods and by an improved analysis of the obtained data. New aspects of screening examinations for gastrointestinal cancer in high risk groups concern endoscopic-bioptic methods, the endoscopic retrograde cholangio-pancreaticography, the ultrasonically-guided percutaneous fine-needle biopsy and immunological procedures. An increasing number of gastrointestinal peptides can be determined by radioimmunoassay. Breath tests may improve diagnosis in malassimilation.
| 61,155
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Reverse plaque formation by hog cholera virus of the GPE-strain inducing heterologous interference.
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A simple and rapid plaque procedure was developed for the assay of hog cholera virus (HCV) of a particular strain, GPE-, based on its intrinsic interference with vesicular stomatitis virus (VSV) on the primary swine testicle cells and on an established swine kidney cell line; the procedure is called the reverse plaque formation (RPF) method. The plaques were produced as colonies of HCV-infected cells which were VSV-sensitive, disintegrated cell sheet. These plaques became visible after 15 to 20 h of superinfection with VSV done 2 days after an initial inoculation of the GPE- strain. The plaque formation was inhibited by a specific antiserum against HCV. All cells within the plaque had HCV antigen detectable by fluorescent-antibody staining. The variations of reverse plaque count were low enough to permit virus titration. The relationship between virus concentration and the number of plaques was essentially linear. The titer measured by the RPF method was a little higher than that of the tube culture interference method.
| 61,176
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Results of virological and serological studies of three influenza A Hong-Kong epidemics in Leningrad.
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An analysis of morbidity of the population in the course of 3 influenza A/Hong-Kong epidemics showed a pronounced decrease in influenza affection of adult population in the last epidemic in 1971--1972. Comparative studies of the diagnostic value of CFR and HIT demonstrated identical sensitivity of CFR as a method of influenza diagnostics in both the epidemic and interepidemic periods. HIT was suitable for the detection of influenza only in the epidemic period. In the interepidemic period, the percentage of influenza infection diagnosed by means of HIT amounted to only 23--24 of all serologically confirmed cases of influenza. The highest percentage of virus isolation was observed when material from patients with serologically confirmed influenza was used. All strains of influenza A virus isolated in 1969 and 1970 were similar in their sensitivity to inhibitors of animal sera. Suring the last influenza epidemic, 2 of the 136 isolated strains were found to be resistant to gamma inhibitors and highly sensitive to the inhibitors showed their close relationship to gamma inhibitors. Antigenic analysis of the influenza A strains isolated during the 3 influenza epidemics revealed changes in the antigenic structure of the agents of the influenza epidemic in Leningrad in comparison with the standard strain A/Hong-Kong/I/68 (H3N2).
| 61,243
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Effect of cyproterone acetate on androgen-dependent synthesis of alpha2u globulin in rats.
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Cyproterone acetate (CA, 2-5 mg/100 g body wt) inhibited androgenic induction of alpha2u globulin in spayed rats. In mature male rats, which normally produce alpha2u globulin, ten daily injections of CA did not inhibit synthesis of this protein. Long-term treatment of mature male rats (two injections every week for 12 weeks) showed only slight inhibition of alpha2u synthesis after 10 weeks of CA treatment. CA also failed to compete with 5alpha-dihydrotestosterone for the cytosol androgen-binding protein of male rat liver. The inhibitory effect of CA on the primary induction of alpha2u globulin in the spayed rat and its lack of effect on continued synthesis of this protein in maximally induced mature male rats are consistent with the hypothesis of a two-step mechanism for androgenic regulation of alpha2u synthesis, an initial CA-sensitive step followed later by a CA-insensitive step.
| 61,248
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Recovery curves of the blink reflex during wakefulness and sleep.
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The paired shock technique was used to study the effect of sleep on the excitability of the short latency R1 and long latency R2 components of the electrically elicited blink reflex. During wakefulness, R1 returned, after transient potentiation, to its original level in about 150 ms following the conditioning stimulus. Contrastingly, R2 remained profoundly suppressed up to 800 ms, suggesting sustained reduction of excitability of the polysynpatic reflex pathways after the passage of a preceeding impulse. During non-REM and REM sleep, the recovery curve of R1 was similar in character, although different in time course to the one obtained during wakefulness. However, R2 was potentiated rather than suppressed by the conditioning stimulus during both phases of sleep. These findings indicate that, during sleep, the polysynpatic reflex pathways are not inhibited by a preceeding impulse to the same degree as in wakefulness.
| 61,259
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[Electric-sensoric examination and EEG to localize the focus of symptomatic epilepsy (author's transl)].
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Somatosensory cortical evoked potentials (SRAP) have been studied in normal subjects and in epileptic patients. The value of this method with regard to intracerebral localization was compared with the results obtained by EEG, scintigraphy, arteriography and surgical exploration. Contralateral evoked potentials were recorded after electrical stimulation of the dorsum of the foot (spinal segment L5) and the ulnar side of the hand (spinal segment C7 or C8). Details of the methods are published elsewhere (Baust et al., 1972). In cases of symptomatic epilepsy the evoked potentials were abnormal, pathological or absent over the specific cortical area independent of whether there was an EEG focus or not. In cases with a normal EEG the changes in the evoked potentials were seen over that hemisphere which was localized by scintigramm, arteriography or surgery as being the side of the lesions (Fig. 1). The patients investigated here suffered from jacksonian epilepsy or grand mal with focal origin; pathologically the angiomas are to be mentioned in particular where the SRAP alterations, and not the EEG, demonstrate the damaged hemisphere (Fig.2). It can be concluded that the study of somatosensory evoked potentials can give more detailed information than the conventional EEG in cases of symptomatic epilepsy with a normal EEG.
| 61,261
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Rat alpha-fetoprotein: isolation, radioimmunoassay and fetal-maternal distribution during pregnancy.
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A method is described for the isolation of mg quantities of two forms of rat alpha-fetoprotein (AFP) from amniotic fluid by preparative disc-gel column electrophoresis using a continuous elution system. AFP isolated by this method is suitable for use as an antigen, can be labelled for use in a radioimmunoassay and serves as a reference standard. The characteristics of a new antiserum to AFP are also described. The protocol for a radioimmunoassay is outlined which permits the measurement of AFP in several fetal-maternal physiological compartments throughout gestation. Levels of AFP in fetal liver and fetal plasma suggest that secretion of AFP from liver occurs soon after synthesis with minimal hepatic storage. The pattern for AFP in maternal serum parallels that observed in amniotic fluid and fluctuations in maternal serum levels of AFP appear to be buffered by AFP accumulation in amniotic fluid. Fetal clearance of AFP under normal conditions may be relatively constant from Days 11-20 of gestation since an amniotic fluid: maternal serum AFP ratio of 30:1 is maintained during this period.
| 61,274
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Mouse virulent strain of Staphylococcus epidermidis. Relation of antiphagocytic activity to the protection-inducing antigen.
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Using 10(9) or 10(7) colony-forming units of a strain of Staphylococcus epidermidis (strain 1142) in saline or 5% mucin, respectively, 90 to 100% of mice died within 24 to 48 hr after intraperitoneal challenge infection. These organisms gradually multiplied in the peritoneal cavity when injected intraperitoneally into mice, while the mouse avirulent strain (strain 1124) rapidly decreased and no organisms were found there 20 hr after injection. This strain was capable of inducing resistance against challenge with homologous strains. The resistance appeared as early as the first week and disappeared the 4th week after the immunization. However, no resistance was induced with strain 1124 against challenge with strain 1142. Also, hyperimmune rabbit serum prepared with strain 1142 passively protected against challenge with homologous strain in mice. The protective antibody was absorbed out with homologous organisms but not with strain 1124. Subsequently, a surface substance was obtained from strains 1142 or 1124 by the method of Morse. The 1142 surface substance was capable of inducing a resistance against challenge with the homologous strain but not with the 1124 surface substance. Also, this substance absorbed the protective antibody in hyperimmune rabbit serum prepared with the homologous strain but not with the 1124 surface substance nor with the Smith surface antigen extracted from the Smith strain of Staphylococcus aureus. Conversely, the protective antibody in rabbit anti-Smith strain serum against challenge with the homologous strain was absorbed with the Smith surface antigen but not with the 1142 surface substance. In the agar diffusion test, the 1142 surface substance and the Smith surface antigen produced single precipitin lines only against homologous antisera. Biochemical analysis of the 1142 surface substance showed that the substance contained neither nucleic acids nor proteins but is composed of hexosamine, glycerol, phosphorus, alanine, glycine and phenylalanine.
| 61,300
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A suppressor T-cell defect in tropical splenomegaly syndrome.
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Serum-IgM is always abnormally high in tropical splenomegaly syndrome. It is postulated that patients with this disease have an abnormal immunoglobulin response to malaria because they lack effective T suppressor cells. This defect may be genetically determined, thus explaining the tribal and familial aggregation of the disease. Hypermacroglobulinaemia is associated with the formation of large amounts of high-molecular-weight immune complexes. These complexes are important in the pathogenesis of the clinical features of the syndrome.
| 61,346
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Rational choice of penicillins and cephalosporins based on parallel in-vitro and in-vivo tests.
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Because of the unavailability of strictly comparable data, seven representative penicillins and the five cephalosporins currently used in Britain were evaluated in parallel, both in vitro and in vivo. Penicillin sensitive and resistant strains of Staphylococcus aureus and Proteus mirabilis were the main test organisms. Minimum bacteriocidal concentrations of cloxacillin, flucloxacillin, cephalothin, and cephazolin in serum were much higher than conventional minimum inhibitory concentrations in the absence of serum. Cephalexin and cephradine showed the smallest divergence in these values. Staph, aureus beta-lactamase caused least damage to methicillin and cephradine, whereas enzymes from Escherichia, Klebsiella, and Bacillus cereus had least effect against cephradine followed by cephalexin. In mouse protection experiments, highly protein-bound antibiotics had relatively low efficacy. Cephradine had the highest mean activity followed closely by cephaloridine and cephalexin. From the data, cephradine was the cephalosporin of choice, and firm decisions were also made about the choice of penicillins.
| 61,353
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The management of stillbirth: coping with an unreality.
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With about 1 stillbirth occurring in every 80 deliveries, stillbirth is a common tragedy. Yet it is an event which, by common consent, is cloaked in secrecy, and which by its very nature seems unreal. There are thus strong forces operating on the bereaved mother and her family, and on the professionals who care for them, to keep the crisis of stillbirth hidden away, therby in fact hindering the mourning and healing process. Bourne has produced statistical evidence to show that family docotrs are astonishingly reluctant to know or remember anything about the patient who has had a stillbirth. I would like to put forward some suggestions for helping doctors to overcome their reluctance to face the problem of stillbirth.
| 61,354
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"Anabolic" effects of methandienone in men undergoing athletic training.
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After failure to confirm an anabolic action of testosterone and its derivatives in rats, methandienone ('Dianabol', an "anabolic steroid" used by athletes) has been given to 11 athletic men during a course of weight-training, in a double-blind, crossover experiment. The dose of methandienone was 100 mg/day for 6 wk. Body weight and composition, muscular strength and performance, and indices of endocrine function were studied. Compared with the placebo period, on methandienone the subjects gained weight (mean 3-3 kg +/- 0-6 kg) and accumulated a disproportionately large amount of potassium (420+/-68 mmol); the increase in weight was confined to the lean part of the body, and the muscles increased in size. Strength and performance improved over each training period, but not significantly differently on drug and placebo. On the drug, plasma-cortisol concentration and urinary cortisol excretion increased, and plasma-testosterone decreased. Although the weight and body-composition changes may demonstrate an anabolic action of methandienone in man, they may alternatively have been caused by an increase in intracellular fluid, and the question of anabolic action therefore remains open.
| 61,389
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Extra-amniotic prostaglandin E2 and the unfavourable cervix.
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A small dose of prostaglandin E2 suspended in a viscous medium was instilled as a single application into the extra-amniotic space of patients with unfavourable induction features the day before planned induction in an attempt to improve the condition of the cervix. Two groups of 15 patients were studied, one receiving prostaglandin E2 250 mug suspended in methyl ethyl cellulose ('Tylose') 6% solution, and the other tylose alone. Cervical status did not change in those receiving tylose alone, whereas a significant improvement occurred in 14 out of 15 patients receiving the prostaglandin. Labour began before formal induction in 1 patient receiving tylose and in 8 receiving prostaglandin.
| 61,394
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HLA antigens and atopic features in steroid-responsive nephrotic syndrome of childhood.
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Atopic systems were more common in children with steroid-responsive nephrotic syndrome (S.R.N.S.) than in matched controls, and HLA-B12 was more common in children with S.R.N.S. than in adult controls. Atopic symptoms (particularly hayfever), positive prick tests with grass pollen antigens, and a higher mean serum concentration of IgE antibody to timothy grass pollen were more common in nephrotic children with HLA-B12 than in those without HLA-B12. There was also an increased frequency of the haplotype HLA-A1 and HLA-B8, mainly among the non-atopic patients.
| 61,442
|
An integrated view of the metabolic and genetic basis for obesity.
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The propensity to obesity in animals and man identifies those individuals who are genetically favoured to survive when food supplies are scarce. Obese subjects are limited in their ability to produce heat, either in a cold environment or after food, because of a reduced activity in skeletal muscle of a "futile" cycle in glucose metabolism. The impaired thermogenesis reduces the maintenance requirement for energy in the pre-obese individual so that a "normal" energy intake can only be balanced by excessive exercise or the expansion of adipocytes. The basal metabolic rate rises as obesity develops and compensates for the impaired thermogenic mechanism.
| 61,444
|
Amine metabolism and the small bowel in uraemia.
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Intestinal intubation was carried out in 21 subjects: 9 with end-stage renal failure, 2 with early renal insufficiency, 7 untreated patients with blind-loop syndrome, and 3 normal volunteers. All 9 patients with uraemia had significantly raised duodenal dimethylamine (D.M.A.) concentrations compared with the other groups tested. Alteration of the intestinal bacterial flora with antibiotics markedly reduced serum D.M.A. and trimethylamine concentrations and modified the symptoms. Potentially toxic metabolites in the small bowel might have significant nutritional and toxic sequelae in uraemia and these findings suggest that current therapeutic approaches to the treatment of end-stage kidney disease should be re-examined in relation to bowel flora.
| 61,496
|
Propranolol in the treatment of thyrotoxicosis: a review.
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The clinical manifestations of hyperthyroidism have suggested to physicians for many years that the sympathetic nervous system may be involved in their production. Despite this, the precise interrelationship between the thyroid gland and the sympathetic nervous system has never been defined but controlled investigations have shown that hypersensitivity to catcholamines does not occur in animals or man with artificially produced thyrotoxicosis. In recent years beta-adrenoceptor blocking drugs, and in particular propranolol, have been used in patients with hyperthyroidism. Evidence exists that they control some of the peripheral manifestations of the disease, including nervousness, palpitations, tachycardia, increased cardiac output and tremor, but they do not appear to affect the underlying thyrotoxic process itself. Propranolol has been used with sucess in the treatment of acute hyperthyroid crisis, in pre-operative preparations for thyroidectomy, for the control of symptoms and signs following the administration of radioactive iodine therapy and antithyroid drugs, during the period of diagnostic thyroid investigations and occasionally as the sole therapy. The supportive role of propranolol in the management of hyperthyroidism is now established and in some instances such as radioactive iodine therapy, it has enabled improvements in the existing methods of treatment to be achieved.
| 61,585
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An RNA-dependent DNA polymerase, different from the known viral reverse transcriptases, in the chicken system.
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The properties of an RNA-dependent DNA polymerase (an RNA-dependent DNA nucleotidyltransferase), which occurs ubiquitously in the allantoic fluid of uninfected, leukosis-virus-free eggs, are described. It is shown that the enzyme can synthesize faithful transcripts from natural RNA (globin mRNA). By biochemical and immunological methods, the enzyme can be clearly distinguished from the reverse transcriptases of the known chicken RNA tumor viruses and therefore seems to be a member of a so far unknown class of chicken polymerases.
| 61,587
|
[Programmed typing in a school for the physically handicapped - testing a new audiovisual learning system (author's transl)].
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Within the framework of a test performed at a school for the physically handicapped, 10 pupils with disabilities varying in type and degree of severity completed a typing programme which was adapted to their individual physiological possibilities. The deliberate use of audiovisual media contributed both to an adaptation to the disability, motivation of the pupils and intensification of the learning process. The assessment of the test results illustrated the success rates which can be expected if such a learning programme is carried out with physically handicapped pupils.
| 61,606
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Effect of organ culture on the survival of thyroid allografts in mice.
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Mouse thyroid can be maintained in organ culture for 4 weeks. Uncultured BALB/c thyroid is rejected 10-15 days after transplantation under the kidney capsule of H-2 disparate recipients (C57BL, CBA). Organ culture of thyroid tissue prior to transplantation prolongs allograft survival. This prolongation of graft survival increases with increasing time in culture and 80-90% of BALB/c thyroids maintained in culture for 26 days survive in allogeneic CBA recipients for a 60- to 70-day test period. These allografts show normal function as measured by 125I uptake, and show no histological evidence of chronic rejection. Cultured allografts can be rejected if the host's immune system is stimulated with viable leukocytes of donor origin. Host animals carrying a functioning allograft are not tolerant of donor tissues and will reject a second uncultured allograft from the same donor strain.
| 61,634
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Immunological enhancement of rat renal allografts using rabbit antisera with specificity for rat transplantation antigens.
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Rabbits immunized with particulate and soluble preparations of rat lymphoid tissue of the HO strain produced antisera which reacted without strain specificity on rat lymphocytes. Absorption of the sera with tissue from the AS strain of rat removed the antibodies reacting with AS tissue leaving activity against HO cells only. Studies with backcross rats showed that the antigens detected by these sera were products of the AgB genes or genes segragating with them. The immunosuppressive activity of rabbit antisera specific for Ag-B5 rat transplantation antigens was tested in a rat renal allograft assay. Some of the antisera markedly prolonged the survival of (AS X HO)F1 kidneys transplanted to AS rats. The prolongation of graft survival was not due to ALS activity since the sera were active in the absence of antibody directed against recipient antigens. There was no correlation between in vivo enhancement and anti-donor lymphocytotoxic titres of the xenoantisera.
| 61,635
|
Ultrastructural study on the meiotic prophase nucleus of rat oocytes.
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Rat oocytes in the meiotic prophase are studied by means of classical techniques of electron microscopy, preferential staining methods for DNA and RNA and specific enzymatic hydrolysis. The axial cores in leptotene and the lateral arms in the pachytene synaptonemal complex are composed by fibrils that keep a positive contrast after the application of the ethylenediaminetetraacetic acid staining method. They disappear with RNAse treatment, which reveals the presence of chromatin fibrils in the zone occupied by the cores. Preferential staining for DNA corroborates this evidence. Medial arm and lateral-medial fibrils are formed by ribonucleoproteic filaments that form bridges between pairing homologues in the zygotene. In the advanced pachytene stage, the RNA becomes scarce in these structures. No DNA can be detected either in the lateral-medial fibrils or in the medial arm. During diplotene the synaptonemal complex loses its individually and the synaptic space becomes wider and irregular. At the same time, loss of chromatin and a large increase of RNA-containing particles occur. These processes lead to the typical interphasic arrangement of nuclear components seen in the dictyate stage.
| 61,697
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Immunological cross reactivity of four enzymes involved in the biosynthetic pathway of lysine, methionine and threonine in Escherichia coli K12.
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In Escherichia coli K12 the biosynthetic pathway of lysine, methionine and threonine is characterized by three isofunctional aspartokinases and two homoserine dehydrogenases. A single polypeptide chain carries the threonine-sensitive aspartokinase and homoserine dehydrogenase (AK I-HDH I), and a different polypeptide chain carries the methionine-repressible aspartokinase and homoserine dehydrogenase (AK II-HDH II). Immuno-adsorbants prepared with rabbit antibodies against AK I-HDH I bind the lysine-sensitive aspartokinase (AK III), the AK II-HDH II, and the homoserine kinase (HSK), an enzyme of the threonine biosynthetic pathway. Saturation of the immunoadsorbant with AK I-HDH I results in a decreased binding capacity for the other enzymes. Displacement of bound AK III or HSK can be obtained with pure AK I-HDH I, showing that the affinity of the antibodies to homologous antigens is higher than to heterologous ones. Immunoadsorbants prepared with anti-HSK antibodies show the same type of recognition: binding of the three aspartkinases and a capacity to displace the heterologous antigens bound. Accordingly, the same antibodies, implicated in the binding of the homologous antigen, bind the other enzymes. None of the other enzymes of the pathway, or the other kinases tested are recognized by the two immunoadsorbants. It can be postulated that in E. coli K12, duplication of a common ancestor gene gave rise to the three aspartokinases and to the homoserine kinase; two of the genes coding for the aspartokinases fused with those coding for the homoserine dehydrogenases. Indicating that only few epitopes are shared by these enzymes, by conventional immuno-diffusion techniques no precipitation lines appeared with antibodies against AK I-HDH I and the other proteins.
| 61,712
|
Histological localization of nervous-system antigens in the cerebellum by immunoperoxidase labeling.
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The indirect immunoperoxidase method was used to localize histologically on sagittal sections of mouse cerebellum antigenic determinants detected by the following antisera: anti-NS-2, anti-NS-3, anti-NS-4 rabbit anti-bovine corpus callosum, rabbit anti-mouse brain, rabbit anti-glial fibrillary acidic protein, and rabbit anti-neurofilament protein. Anti-alpha-bungarotoxin serum and normal rabbit serum were used as negative controls. The various sera showed similarities in staining pattern as well as differences. Anti-NS-2 antiserum labeled the somata of interneurons in the molecular layer, granule cell bodies, glial cells in the white matter, and along the surfaces of blood vessels. A similar pattern of staining is produced by the anti-NS-3 antiserum except that glial cells are less prominent in the white matter and the blood vessels are not visible at all. Anti-NS-4 antiserum does not label interneurons but does label glomeruli and, less intensely, granule cell bodies in the granular layer. Rabbit anti-mouse brain antiserum is similar to anti-NS-4 antiserum except that fiber tracts in the white matter are stained more intensely; Rabbit anti-bovine corpus callosum labels only white matter. Antisera to neurofilament ans astrocytes.
| 61,794
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Gene activation of molecules with carcinoembryonic antigen determinants in fetal development and in adenocarcinoma of the colon.
|
"Fingerprints" of 0.9% NaCl solution extracts obtained from fetal guts and individual adenocarcinoma of the colon show a randomized pattern of expression of carcinoembryonic antigen (CEA) determinants by CEA radioimmunoassay and isoelectric focusing. All CEA-containing antigens found in a pool of 20 primary adenomas were found at some stage in fetal development. No single CEA-reacting peak was typical of any one period of fetal development. When fetal gut profiles were grouped according to trimester in utero, however, an expanded gene pool was found in the second trimester which correlates well with maximum gastrointestinal growth and differentiation. Isoelectric focusing-CEA radioimmunoassay profiles of individual primary adenomas were similar to but never identical with individual fetal gut profiles. "Fingerprints" of metastatic adenomas of entodermal origin showed quantitative and qualitative increases in molecules with CEA determinants unlike these latter categories. Such data suggest that both integrator and controller gene activities may be lost in metastatic disease. Rather than "phase-specific gene sets" on different chromosomes being activated by various oncogenic modalities, it is more probable that individual chromosomes are involved in oncogenesis. While more data are needed to confirm this idea, it is safe to say that the expression of molecules with CEA determinants need not be caused by either derepressive or reexpressive gene activation. These data point to the individuality of gene expression of molecules with CEA determinants both in fetal development and in early neoplasia. Since CEA-reacting molecules were not found in tumors of ectodermal or mesodermal origin by these methods, such products should be termed carcino-developmental antigens of entodermal or colonic origin.
| 61,812
|
Cell surface antigens. IV. Immunological coorespondence between glycophorin and the a1 human cell surface antigen.
|
A stable human-Chinese hamster ovary cell hybrid has been produced which, in addition to the complement of Chinese hamster ovary (CHO-K1) chromosomes, contains only one human chromosome, No. 11. The human cell-surface antigens whose expression is controlled by human chromosome 11, and are expressed by this hybrid, have been defined as the AL immunogenetic complex. Although one component of this immunogenetic complex (a1) is also expressed by human red blood cells, a second component (a2) is not. Killing of an a1+ hybrid by anti-a1 serum and complement can be completely inhibited by glycophorin, the major glycoprotein component of the human erythrocyte membrane. In the presence of complement, antiserum prepared against glycophorin will kill only those cells which express a1. The anti-a1 killing activity of the anti-glycophorin can be absorbed out only by those cells which express a1. Therefore, it is concluded that the a1 cell-surface antigen has at least one antigenic component in common with glycophorin.
| 61,843
|
Effect of Hoechst 33258 on Chinese hamster chromosomes.
|
Cells of the Chinese hamster strain C-125 were treated for different time intervals with H 33258, a bibenzimidazole derivative. The same compound was used to stain fixed cells of the same strain. H 33258 induced in cells in culture specific areas of reduced spiralization on the metaphase chromosomes of some cells. These probably correspond to DNA segments rich in A-T bases interspersed along the chromosomes. Probably H 33258 acts during S period of cell cycle. The banding obtained by staining with H 33258 is similar to that induced by quinacrine dihydrochloride but shows a better resolution.
| 61,845
|
Activity of neuronal populations of human subcortical structures during sleep.
|
Multi-unit activity of 14 subcortical structures was studied during drowsiness and sleep in patients with depth electrodes implanted in the brain for therapeutic purposes. The mean firing rate of the multi-unit activity was found to decrease during "slow-wave" sleep in each cycle. The multi-unit activity was sharply increased during paradoxical sleep. In successive sleep cycles the mean firing rate somewhat increased from cycle to cycle during slow sleep. The mean firing rate was considerably increased during wakefulness after a sufficiently logn sleep, as compared with the initial background values. Fluctuations of the mean firing rate were characteristic of paradoxical sleep. When studying simultaneously 2 or 3 structures, both uniform or different changes of the neuronal activity were possible. Changes of the firing rate in separate structures may develop a few seconds prior to the "clinical display" of the REM phase. All (or nearly all) the structures, whose activity during sleep is rather independent, are presumed to be able to be a source of the REM phase.
| 61,850
|
Sleep patterns of the laboratory cat.
|
The effects of feeding schedule and external stimuli on sleep patterns were investigated in cats fed to maintain their mean body weight. The ECoG, EOG and EMG wer recorded from 3 male cats fed once daily and under a 12:12 light--dark schedule. The results for 15 working days were compared with those obtained at week-ends and under continuous lighting, fasting, reduced food intake or overfeeding. Feeding was also divided into 3 meals per day. Despite some differences in their responsiveness. All cats exhibited the usual values for the critical variables of SWS: diurnal placement, intermittency and total amount. A low percentage of PS per 24 h was recorded. This was related both to the restricted amount of food eaten and to the feeding schedule. Reduced external stimuli at week-ends resulted in concentration of sleep during daytime, whereas sleep was reduced during continuous lighting in conjunction with an increased percentage of drowsinessess. The most marked effect of fasting (pig fat) was fragmentation of sleep episodes. Divided meals and an increased food intake both increased the total sleep duration. It is suggested that the restricted amount of food and relatively enriched environment used, accompanied by a reduced sleep duration, may be comparable to that seen in free animals. Sleep patterns in the cat are very responsive to light--dark schedule, reduced external stimuli and fasting.
| 61,852
|
Conditioned EEG desynchronization and seizure occurrence in patients.
|
Five patients with seizures poorly controlled by standard anticonvulsant medication, underwent EEG operant conditioning. The operant paradigm reinforced the production of low voltage fast activity while decreasing frequencies below 10 c/sec. Seizure frequency decreased in 2 patients, seizure severity was attenuated in 2 others, and one patient who was only given reinforecement for scalp EMG suppression whowed no change in seizure parameters. Pseudoconditioning and control periods ruled out placebo effects. A rationale for this phenomenon is proposed.
| 61,854
|
Identification of the triploid genome by the C-banding method.
|
We report on cytogenetic studies of a malformed fetus, whose clinical symptoms indicated the diagnosis of triploidy. This was confirmed by chromosome analysis of peripheral lymphocytes of cord blood. Using the C-banding method it was possible to identify the origin of the extra haploid set: marker chromosomes indicate, that nonreduction of the first meiotic division in the father's spermiogenesis most probably leads to triploidy. However, in our case fertilization of the zygote by two sperms cannot be excluded.
| 61,860
|
Deletion of hinge region of human myeloma IgG1 molecule (protein LEC) associated with nonexpression of G1m (3) and Km (1, 2) allotypes. A possible genetic explanation at the DNA level.
|
In this paper we report the structural basis for the nonexpression of G1m(3) and Km (1,2) allotypes in an IgG1 (kappa) human myeloma protein (protein LEC). Heavy and light chains spontaneously dissociate in sodium dodecyl sulfate polyacrylamide gels. Light chains appear to be covalently S-S bonded. Analysis of cysteine-containing peptides shows that the heavy chain of the IgG protein LEC has a deletion of residues 216-230, thus encompassing the entire hinge region. An arginine residue, characteristic of the G1m(3) marker is present at position 214. An alanine at position 153 and a leucine at position 191 of the light chain, characteristic of the Km (1, 2) allotypes, are present. It is likely that the double Km and Gm lack of expression is the result of the deletion. The genetic implications of the sequence of this protein are discussed.
| 61,877
|
Effect of bilateral adrenalectomy and parenteral betamethasone on gastric mucosal mast cell population in albino rats.
|
The histamine-laden mast cells of gastric mucosa in albino rats are shown to degranulate on administration of Betamethasone, but they increase in number in adrenalectomized rats. It is concluded that Betamethasone, and also adrenal glucocorticoids increase gastric secretion by liberating histamine from mast cells and histamine in turn acts on the gastric glands.
| 61,891
|
Experimental allergic encephalomyelitis: role of fibrin deposition in immunopathogenesis of inflammation in rats.
|
The immunopathogenesis of experimental allergic encephalomyelitis (EAE) is reviewed with special focus on the role of central nervous system fibrin deposition in the inflammatory cascade characterizing this autoimmune disease. Among rats sensitized to whole spinal cord or myelin basic protein of either guinea pig or bovine origin, there is a striking degree of concordance of perivascular fibrin deposits and occurrence of clinical paralytic signs. Neither paralytic signs nor fibrin deposition are temporally related to development of perivascular cellular infiltrates. Rats sensitized to neuroantigen and treated with ancrod, a polypeptide derived from the venom of Agkistrodon rhodostoma, develop profound hypofibrinogenemia, have a marked inhibition of fibrin deposition, and often exhibit no paralytic signs whatsoever. In contrast, cellular infiltrates are not demonstrably influenced by ancrod treatment. Activation of the clotting cascade at loci of developing immune injury of nervous tissue appears to result from and lead to increasing neurovascular permeability and accumulation of edema fluid. Distention of the extracellular space in central and peripheral nervous system tissues by edema fluid appears to be directly responsible for clinical abnormalities characterizing EAE in rats. Cellular infiltrates, on the other hand, appear to be an independent immune response to neuroantigenic sensitization.
| 61,895
|
Effects of injury on the concentration of alpha1-macroglobulin and alpha2-macroglobulin in the plasmas of male and remale rats.
|
The effects of injury on the concentration of alpha1-macroglobulin and alpha2-macroglobulin in the plasmas of male and remale rats has been investigates. At 5 days after injury to the male rats the alpha1-macroglobulin concentration increased to 131% of its preinjury value. The alpha2-macroglobulin concentration increased more rapidly to a maximum of 86 times its initial value. In the female rats alpha2-macroglobulin increased only slightly and alpha1-macroglobulin not at all.
| 61,894
|
A comparative study of the effects induced by MCN-A-343 and acetylcholine on the isolated toad rectus abdominis.
|
McN-A-343 (McN), a non nicotinic ganglionic stimulant, induced slow contractile responses of the toad rectus abdominis. A relaxation was also observed when large doses were added in the presence of a contraction caused by acetylcholine (Ach). The relaxation induced by McN could not be overcome by increasing Ach concentration. Bell-shaped log dose-response curves were obtained for McN. d-Tubocurarine caused an unusual change on these curves, suggesting an indirect action of the agonist. This possibility was corroborated by the fact that hemicholinium, procaine, and cold storage of the muscle caused a marked decrease of the organ sensitivity to McN but not to ACh.
| 61,902
|
Practical approach to the diagnosis of sudden unexpected death of cardiac origin.
|
Experiences concerning the practical demonstration of recent myocardial lesion (infarction) with various conventional and enzyme-histochemical methods are explained. It has been found in our laboratory that besides careful inspection of the heart, additional useful information can be obtained with ordinary H-E staining and beta-OH butyrate dehydrogenase reaction on frozen sections. Myocardial cells are darkly eosinophilic in the areas of infarction. Uneven staining in the dehydrogenase reactions was regarded as a sign of lesion in that section. beta-OH butyrate dehydrogenases revealed the damage more clearly than succinate and malate dehydrogenase. The enzyme reactions were usable as late as 7 days after death if decomposition had not commenced.
| 61,930
|
The use of non-deparaffinized tissue sections for staining leprosy bacilli.
|
Reduced acid-fast staining of leprosy bacilli occurs during the dewaxing of paraffin sections by xylene and alcohols; the older and more decrepit bacilli being especially affected. By the use of non-deparaffinized sections, the leprosy bacilli which could not be stained with the usual carbol fuchsin are strongly stained. Moreover, non-deparafinized sections can be used for the periodic acid-carbol pararosanilin stain or methenamine silver stain for demonstrating mycobacteria.
| 61,950
|
[Alpha feto protein. Normal pregnancies and maternal diseases. Apropos of 3,010 radioimmunologic determinations].
|
Using an immunological technique limits of normal levels of AFP in maternal blood have been worked out during pregnancy from a series of 3010 samples of blood. Comparing mean curves for the levels of AFP in mothers suffering from anaemia and diabetes with normal curves shows that there is a significant rise in these levels in the third trimester of pregnancy. The possible mechanisms and their relationship to the variation levels of AFP are discussed.
| 61,982
|
Nucleoside specificity in the carrier IgG-dependent induction of tolerance.
|
Induction of tolerance to nucleoside haptens in BALB/c mice with isologous IgG conjugates bearing four nucleosides simultaneously (A, G, C, T)-IgG was confirmed. A mixture of separate nucleoside-IgG tolerogens (A-IgG, G-IgG, C-IgG, and T-IgG) was as effective or more effective that the (A, G, C,T)-IgG form in suppressing the response to (A, G, C, T)-KLH. The nucleosides acted independently and simultaneously, since tolerogens with varying combinations of nucleosides caused specific suppression of the respones to only those nucleosides present on the tolerogen. Nucleoside-IgG conjugates did not suppress the response to denatured DNA-methylated bovine serum albumin, in which larger oligonucleotide determinants predominate. In varying combinations, guanosine was the dominant nucleoside both for immunization and for induction of tolerance. After three or four immunizations, control immunized animals made mainly IgG anti-nucleoside antibodies and this IgG antibody formation was preferentially suppressed in tolerogen-treated animals. Tolerance could be established before the primary or secondary immunization and it then persisted for at least 75 days through a fourth course of immunization. The same dosage of tolerogen did not reverse a strongly established anti-nucleoside antibody production after a tertiary response.
| 61,997
|
Tryptic cleavage of antibody binding sites from hepatitis B surface antigen particles.
|
The sedimentation of radiolabelled 22 nm hepatitis B surface antigen particles was unaffected by treatment with either trypsin or SDS alone, but combined treatment disrupted the particulate nature of the radiolabelled material. Considerable antibody binding activity by the group-specific determinant (a) was preserved after combined SDS and trypsin treatment but was released from the bulk of the radiolabelled protein; gel filtration indicated an approximate mol. wt. of 5000 to 15000 for the released antibody binding material. This material was precipitated by concanavalin A, suggesting the presence of carbohydrate. Its serological activity was remarkably resistant to boiling and to proteolytic digestion, but was partially sensitive to treatment with 0-01 M-periodate or with mixed carbohydrases and neuraminidase, and was greatly reduced by treatment with reducing agent. These data suggest that the stability of the a determinant is due to the structure of the antibody binding site itself, rather than to involvement in the quaternary structure of the particle, and that intact disulphide bonds and carbohydrate, closely related to the antibody binding site, are necessary for the full expression of serological acitivity.
| 62,023
|
Plasma membranes of muscle in experimental myotonia in rats.
|
Determinations of protein and phospholipid composition, as well as enzymatic activity, were carried out in plasma membranes isolated from the muscle of rats, after different periods of 20,25-diazacholesterol administration. A decrease in the level of phospholipids, and in the total amount of plasma membrane proteins, connected with a relative reduction in the amount of protein of a molecular weight of 100000 daltons, was found. The activity of (Na+ + K+)-ATP-ase gradually decreased while a reverse tendency was observed in the case of 5'-nucleotidase. Changes in ATP-ase and phospholipids appeared even prior to electrophysiologically recorded signs of the myotonia. The mechanism of these changes and their possible role in myotonia are discussed.
| 62,035
|
Anatomical analysis of ventrolateral thalamic input to primate motor cortex.
|
1. The origin and topographical organization of input to the arm area of the primate motor cortex from the ventrolateral thalamus were examined using the method of retrograde transport of horseradish peroxidase (HRP). 2. A thin, continuous slab of labeled neurons was found in the ventrolateral thalamus followingmultiple injections of HRP into the arm area of the motor cortex. The slab of labeled neurons was flanked, medially and laterally, by groups of unlabeled neurons. 3. The origin of ventrolateral thalamic input was more extensive than previously thought. Labeled neurons were found from A10.0 to A6.0 and occurred in three ventolateral thalamic subdivisions: ventralis lateralis pars oralis (VLo), ventralis lateralis pars caudalis (VLc), and ventralis posterior lateralis pars oralis (VPLo). For simplicity this region containing labeled neurons has been termed the ventrolateral thalamic (VL) arm area. 4. Injections of HRP into the somatic sensory cortex indicated that the thalamic regions which project to the somatic sensory cortex are separate from the VL arm area. 5. The distribution of labeled neurons following single injections of HRP into different regions of the motor cortex arm area indicated that the VL arm area is topographically organized, particularly its caudal part. Ventral regions of the VL arm area were labeled following HRP injections into motor cortex regions adjacent to the central sulcus where the representation of largely distal musculature is localized. Dorsal regions of the VL arm area were labeled following HRP injections into motor cortex regions more rostral to the central sulcus where the representation of more proximal musculature is localized. 6. A larger region of the VL arm area was labeled following HRP injections adjacent to the central sulcus than following the more rostral motor cortex injections. This suggests that, like the arm area of the motor cortex, more of the VL arm area is allotted to the representation of distal than proximal musculature. 7. Following very small cortical HRP injections, isolated labeled thalamic neurons were diffusely scattered throughout a 3-mm rostrocaudal extent of the VL arm area. In addition, a small focal cluster of labeled thalamic neurons was also seen. The labeled cluster was limited to 0.5 mm rostrocaudally and 300 mum in width. The focal distribution of labeled thalamic neurons suggests that aspects of a point to point organization may exist in the connection between VL and the motor cortex arm area.
| 62,039
|
Comparison of graphical and computerized methods for calculating binding parameters for two strongly bound drugs to human serum albumin.
|
The determination of drug-protein binding parameters (n's and K's) can lead to important information on the required therapeutic dosage regimen and possible clinical complications associated with competitive displacement of one drug by a concurrently administered agent. Graphical and computer estimates of the data are often incorrectly formulated, and and seldom are adequate data obtained at low binding ratios. Commonly used graphical procedures, inadequately formulated computer methods, and a statistically correct computer method were used to compare results obtained from a circular dichroic examination of dicumarol-human serum albumin and fenoprofen-human serum albumin interactions. Literature binding constants for dicumarol-albumin range from 1 X 10(5) to 30 times that figure, and it is shown here that a wide range in parameter estimates may be obtained depending on the method of data analysis. The parameter estimates in the case of fenoprofen-albumin are even more variable.
| 62,049
|
Purification of the alpha subunit of avian myeloblastosis virus DNA polymerase by polyuridylic acid-sepharose.
|
The alpha subunit of the avian myeloblastosis virus DNA polymerase could be readily purified to near homogeneity using a polyuridylic acid-Sepharose column chromatography step.
| 62,057
|
New temperate bacteriophage for Bacillus subtilis, rho 11.
|
A new temperate bacteriophage, rho11, isolated by J. Hoch, has been characterized. This new phage is very similar to the temperate phage phi3T in size (380 nm), host range, homoimmunity, DNA buoyant density (1.694 g/ml), antigenicity, and molecular weight (around 6.0 X 10(7)) as determined in gels. Like phi3T, rho11 converts thymine auxotrophs to prototrophy at high frequency (250 out of 250 tested). Phage rho11 differs from phi3T in plaque morphology and in the endonuclease R-EcoRI digest pattern. Sixteen of the 20 rho11 DNA fragments have migration patterns corresponding to those of the 21 fragments of phi3T. The close similarities yet clear differences between these phages suggest that the two phages have a common ancestor.
| 62,060
|
Radioisotope investigation of continuous bladder irrigation after transurethral resection.
|
Radioisotope studies using 131I serum albumin were performed on 20 patients to investigate the possibility of intravascular absorption of the irrigating solution during continuous bladder irrigation after transurethral resection of the prostate. In only 5 of 20 patients was a minimal absorption of 1 to 34 cc observed. On the basis of these studies the routine use of continuous bladder irrigation after transurethral resection can be recommended, provided techniques are sterile.
| 62,061
|
Pneumocystis carinii pneumonia. Diagnosis by examination of pulmonary secretions.
|
To determine if examination of respiratory secretions is useful in diagnosing Pneumocystis carinii pneumonia, smear preparations of expectorated sputum, tracheal aspirates, and transtracheal aspirates stained by the Gomori methenamine silver nitrate method were examined. Pneumocysts were observed more frequently in material obtained by transtracheal aspiration than in secretions obtained by the other methods. Transtracheal aspiration yielded material containing pneumocysts in 8 (13%) of 60 patients; each had pulmonary infiltrates and clinical courses consistent with P carinii pneumonia. Of 330 smear preparations examined from expectorated sputum, three patients had pneumocysts in their sputum and one had organisms in both transtracheal aspiration and expectorated sputum; all three had pneumonia. This study provides evidence that transtracheal aspiration is a useful initial step in the approach to the diagnosis of P carinii pneumonia.
| 62,065
|
[Ventricular fibrillation and asystole precursors in myocardial infarct].
|
Ventricular fibrillation and asystole are a frequent cause of death in myocardial infarction. The data of continuous monitoring the heart in 134 patients with acute myocardial infarction and ventricular fibrillation and asystole. The immediate precursors of ventricular fibrillation were predominantly ventricular extrasystoles. A frequent precursor of ventricular fibrillation consists in paroxysmal ventricular tachycardia. In some patients the ventricular fibrillation was preceded by the block of the bundle of His, non-paroxysmal ventricular tathycardia, escaping contractions and some other arrhythmias. A factor providing for the development of ventricular fibrillation consists in the Q-T interval lengthening on ECG. Ventricular asystole is usually preceeded by atrioventricular block, Stage II-III, and the block of the bundle of His, as well as by ventricular tachycardia and extrasystole, in some cases--by sinus bradycardia and sinoauricular block (weakness of the sinus node). The examination of the rhythm and conductivity disorders preceeding the ventricular fibrillation is of great importance in view of the possibilities of prevention of "arrhythmic death".
| 62,076
|
Experimental induction of hepatocellular hyalin (Mallory bodies) in mice by griseofulvin treatment. 1. Light microscopic observation.
|
Griseofulvin (GF) feeding of mice resulted in protoporphyria, liver cell damage, bile duct alterations, and finally hepatoma formation. In addition, hepatocellular hyalin developed, resembling in its morphology classic Mallory bodies (MB) as seen in alcoholic and nonalcoholic liver disorders in man. Liver cells containing MB often displayed features of severe cell damage and MB were finally released into the sinusoids and degraded by macrophages. The rapid disappearance of MB following GF discontinuation and the reappearance after resumption of GF feeding suggest an intimate relationship between metabolic alterations in the hepatocytes exerted by the drug and MB formation. This assumption is further supported by the fact that MB change their tinctoreal properties in chromotrope aniline blue-stained sections after GF discontinuation, possibly relfecting degeneration. Long term GF treatment apparently primed the liver for MB formation since the cells were able to respond almost instantly with MB to a GF challenge after a 1-month GF-free period.
| 62,098
|
Warfarin sodium in prevention of deep venous thrombosis and pulmonary embolism in patients with fractured neck of femur.
|
In a prospective controlled randomised trial, the prophylactic value of warfarin sodium (in doses aimed at maintaining a "Thrombotest" value of 10% and given from the day of admission until independent mobility had been achieved or for 3 mo, whichever was the sooner) was assessed in 160 elderly patients who had sustained a fracture of the femoral neck. Treatment significantly reduced the frequency of deep venous thrombosis (D.V.T.), whether indicated by the 125I-fibrinogen test during life or assessed by detailed post-mortem studies. Pulmonary embolism was eliminated in treated patients, but the difference in mortality between the treatment and control groups was not significant, indicating that causes of death other than pulmonary embolism are of major importance in these elderly patients. A case is made out for prophylactic anticoagulation on a selective basis.
| 62,111
|
Active specific immunotherapy for ovarian cancer.
|
Ten patients with advanced or recurrent ovarian cancer were treated with a combination of chemotherapy and active specific immunotherapy after tumour stasis had been induced. They were inoculated with irradiated allogeneic cryopreserved tumour cells and B.C.G. once monthly in addition to receiving conventional chemotherapy. The overall duration of "remission", median survival, and projected 24-month actuarial survival in the patients receiving immunotherapy were apparently better than in a retrospectively matched control group treated by chemotherapy alone.
| 62,114
|
Pathogenesis and phenotypes of an X-linked recessive lymphoproliferative syndrome.
|
A new X-linked recessive lymphoproliferative syndrome has variable phenotypes: fatal infectious mononucleosis (I.M.), agammaglobulinaemia after I.M., American Burkitt's lymphoma, histiocytic lymphoma, immunoblastic sarcoma of B cells, or plasmacytoma. An immunodeficiency to rubeola and the Epstein-Barr virus probably ensues from the mutant gene. The phenotypes (spectrum of B-cell disorders) have a common inheritance and the aetiology is similar.
| 62,116
|
Pulsatile blood-flow in arterial grafts.
|
The distensibility of arterial wall is an important factor in the haemodynamics of pulsatile blood-flow. Autogenous-vein grafts have a dynamic response to the arterial pressure pulse (compliance) which approaches that of normal arterial wall, whereas synthetic prostheses are generally incompliant, or become so shortly after implantation. Although synthetic grafts have little effect on steady-state flow, their lack of compliance greatly interferes with pulsatile flow and this may be an important factor in explaining their lack of success as replacements for medium and small sized arteries.
| 62,175
|
Initial treatment of stage IIIA Hodgkin's disease. Comparison of radiotherapy with combined chemotherapy. British National Lymphoma Investigation.
|
117 patients with stage IIIA Hodgkin's disease were randomly allocated for treatment in a multicentre trial comparing the results of total nodal irradiation (T.N.I.) with those of combination chemotherapy. Staging procedures for most patients included laparotomy; a few patients whose staging did not include laparotomy were studied separately. Of the 81 patients staged by laparotomy, 40 out of 42 (95%) achieved complete remission (C.R.) after treatment by T.N.I. and 29 out of 39 (74%) achieved C.R. during treatment with mustine hydrochloride, vincristine ("Oncovin"), procarbazine, and prednisone (MOPP) (P=0.018). An analysis of the disease-free survival up to four years favoured the group of patients treated by T.N.I. (P less than 0.01) but differences in overall survival were not statistically significant. In the 36 patients with presumed IIIA disease whose staging did not include laparotomy no significant differences in the incidence of C.R. or rates of disease-free or overall survival were observed. It is concluded that T.N.I. is the optimum initial treatment for patients with IIIA disease whose staging includes laparotomy.
| 62,265
|
Antenatal diagnosis of neural tube defects.
|
One hundred women with pregnancies at risk for the recurrence of neural tube defects have entered our monitoring programme of echography and alphafetoprotein estimation (AFP) on amniotic fluid and maternal serum during the second trimester. The results of these pregnancies, the application of the programme, sources of error, and the reliability of alphafetoprotein levels are discussed. Conclusions regarding the value of the tests and routine antenatal screening are made.
| 62,270
|
Stepwise biosynthesis in vitro of globin genes from globin mRNA by DNA polymerase of avian myeloblastosis virus.
|
Two approaches have been explored for the synthesis of double-stranded DNA from single-stranded DNA template complementary to rabbit 9S globin mRNA (cDNA). (i) cDNA was elongated with dCMP or dTMP homopolymeric tracts using terminal deoxynucleotidyltransferase (EC 2.7.7.31; nucleosidetriphosphate:DNA deoxynucleotidylexotransferase). cDNA-dC, in the presence of an oligo(dG)10 primer, was an efficient template with either DNA polymerase of Escherichia coli (EC 2.7.7.7; deoxynucleosidetriphosphate:DNA deoxynucleotidyltransferase) or RNA-directed DNA polymerase of avian myeloblastosis virus. cDNA-dT [ with an oligo(dA)10 primer] functioned as template only with E. coli polymerase. (ii) cDNA, without homopolymeric tails, was also efficiently copied in the absence of oligonucleotide primer, by DNA polymerase of avian myeloblastosis virus or of E. coli. The product of the reaction consisted of long hairpin molecules which could be converted into DNA duplex (melting temperature, 93 degrees) by digestion with single-strand nuclease S1. The data indicate that a loop structure on the 3' end of cDNA allowed DNA synthesis to take place by a "self-priming" mechanism. Some of the double-stranded DNA synthesized corresponded to the entire sequence of the 9S mRNA template. The synthesis of full-length double-stranded DNA from mouse globin mRNA and immunoglobulin light chain mRNA is also discussed.
| 62,360
|
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