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Mechanism of compact-colony formation by strains of Staphylococcus aureus in serum soft agar.
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Compact-colony forming active substance (CCFAS), the material responsible for the compact colonies of Staphylococcus aureus observed in serum soft agar, was found to be an alkaline-stable, associated polysaccharide containing galactose, N-acetylglucosamine, ribitol, phosphorus and a small quantity of alanine. This substance, when extracted from strains unable to produce protein A clumping factor, was able to absorb the serum-reacting factor whereas a teichoic acid preparation of one strain could not. The formation of CCFAS was unaffected by the age of the cells, whereas when staphylococci were cultured at alkaline pH, young cells produced more clumping factor than old ones. Both fibrinogen and its degradation products were capable of inducing compact colonies in a strain of S. aureus. The ability of human sera to interact in compact-colony formation was independent of the immunoglobin content. Thus neither protein A, clumping factor, nor teichoic acid participate in the CCFAS reaction.
| 64,587
|
Erythrocyte-UFA (Eufa) mobility test for multiple sclerosis: implications for pathogenesis and handling of the disease.
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Erythrocytes from patients with Multiple Sclerosis (MS) show a highly significant reduction in their absolute electrophoretic mobility in the presence of linoleic and arachidonic acids (LA; AA). Patients with other (destructive) neurological disease (OND) and normal subjects show an increased absolute mobility of their erythrocytes in the presence of LA and AA. About 40 per cent of blood relatives of MS patients show an intermediate type of reaction - being slowed by LA and speeded up by AA. Administration of LA (or gamma linolenate) to an MS patient for some months leads to change in the mobilities from the MS to normal type, the AA result altering first. The effect of LA and AA on the absolute mobility of RBC may thus be used as a simple laboratory test involving a long established technique and eliminating the animal and other needs of the macrophage electrophoretic mobility (MEM) test. The implications of these findings for our understanding and handling of MS are briefly discussed.
| 64,595
|
Toxic polyneuropathies after sniffing a glue thinner.
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In West Berlin in the autumn of 1975 through the following 5 months we observed 18 juvenile patients who had a toxic polyneuropathy and had sniffed a glue thinner. The neurological picture consisted of a symmetrical, progressive, ascending, mainly motor, polyneuropathy with pronounced muscle atrophy and characteristic vegetative alterations. The height of the disease was reached after 1 1/2-2 1/2 months and was characterized by tetraplegia in 7 patients. After 8 months all patients still had a motor deficit. Nerve biopsy showed paranodal axon swelling, dense masses of neurofilaments and secondary myelin retraction. The neurological and morphological data correspond to the "glue sniffer's neuropathy" and the n-hexane and MBK polyneuropathy after industrial exposure, as described in 10 cases to date. However, there was no MBK in the glue thinner. The polyneuropathies occurred in close time relation with the denaturation of the thinner with MEK (2-butanone). It is concluded from the data n-hexane and MBK have a common toxic mechanism with primary axonal changes and that there is an additional synergistic effect of MEK.
| 64,597
|
Comparison of attitudes and cognitive achievement of nursing students in three instructional strategies.
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This study is a comparison of the attitudes and the cognitive achievement of nursing students in three instructional strategies (the traditional lecture, black and white televised instruction, and independent color televised instruction via the Dial Access Information Retrieval System). Though only thirty-one percent (31%) of students indicated prior exposure to independent study methology, sixty percent (60%) identified a desire for active involvement in courses of study. The only significant finding regarding attitudes toward the three strategies was a preference for an greater interest in color videotapes than for black and white televised material. No significant differences in cognitive achievement were noted between any of the three strategies. Implications from the study for curriculum revision are discussed, stressing the probable value of maintaining traditional techniques concurrent with innovative methodological experimentation.
| 64,603
|
Lymphocyte purine 5'-nucleotidase edficiency in primary hypogammaglobulinaemia.
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The mean activity of purine 5'-nucleotidase (E.C.3.1.3.5) in lymphocytes was significantly lower in patients with non-familial adult onset "variable" primary hypogammaglobulinaemia than in non-hypogammaglobulinaemic control subjects. These findings suggest that 5'-nucleotidase activity is necessary for normal lymphocyte function. This may be related to its role in facilitating the transfer of newly formed purines across cell membranes by converting them from nucleotides to nucleosides. This enzyme defect may be a characteristic metabolic lesion in at least some of the patients; alternatively, it may be secondary to some other metabolic defect or plasma-membrane change.
| 64,699
|
Prenatal diagnosis of beta-thalassaemia and sickle-cell anaemia. Experience with 24 cases.
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Prenatal diagnosis of beta-thalassaemia and sickle-cell anaemia was attempted in 24 pregnancies. Adequate amounts of fetal blood (for studying globin-chain synthesis) were obtained in 22 cases. 4 cases of homozygous beta-thalassaemia and 2 of sickle-cell anaemia were diagnosed. The difference between the homozygous and non-homozygous states was well defined. Fetal bleeding from cord puncture and amnionitis resulted in the loss of three fetuses, and methods to avoid these complications are being devised. It is concluded that prenatal diagnosis of disorders of beta-globin synthesis is feasible.
| 64,802
|
Soybean-protein diet in the treatment of type-II hyperlipoproteinaemia.
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A soybean textured protein induced a 14% decrease of plasma-cholesterol levels after two weeks and 21% after three when substituted for animal proteins in a group of 20 patients with type-II hyperlipoproteinaemia. Comparison of soybean diet with a standard low-lipid diet in the same patients, according to a cross-over protocol, indicated that this hypocholesterolaemic effect was not due to differences in the lipid composition of the two diets. The hypothesis that a soy protein has a hypocholesterolaemic action per se is supported by the results of a subsequent experiment in 8 type-II patients in whom the addition of cholesterol (500 mg/day) to soy protein did not modify the hypocholesterolaemic response.
| 64,804
|
Concentrations of pregnancy-specific beta 1-glycoprotein in maternal blood in normal pregnancy and in intrauterine growth retardation.
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A radioimmunoassay has been developed for pregnancy-specific beta 1-glycoprotein (S.P.1), a product of the human placenta. Circulating concentrations of S.P.1 were measured in 153 women in the third trimester of normal pregnancy and in 27 women who delivered children with birth-weight below the 10th centile of the normal range--i.e., with intrauterine growth regardation (I.U.G.R.). Concentrations of S.P.1 showed a skewed distribution and rose progressively to reach a plateau in the last four weeks of pregnancy. In over 70% of women with I.U.G.R. of the fetus, concentrations of S.P.1 were low. Measurement of serum-S.P.1 may provide a new index of fetal wellbeing.
| 64,859
|
Ten model mutagens evaluated by the micronucleus test.
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The following ten mutagenic compounds were subjected to the micronucleus bone marrow test (MNT) in the mouse: cyclophosphamide (CTX), thiotepa (TT), vincristin (VCR), colcemid (COLC), adriamycin (AM), bleomycin (BM), cytosin arabinoside (ARA C), 6-mercaptopurine (6-MP), methotrexate (MTX) and 5-fluorouracil (5-FU). Dose-effect curves were established for all compounds. With the exception of CTX, COLC and AM, the drugs also were subjected to chromosome analyses on Chinese hamster fibroblasts in vitro. The MNT revealed loss of chromatin due to chromosome breakage and rearrangements by CTX, TT and AM, to breakage by ARA C, 6-MP, MTX and 5-FU, as well as loss of entire chromosomes caused by impairment of the spindle by VCR and COLC. With the exception of BM, the effects were demonstrable in the therapeutic dose range. The MNT, provided it is carried out by the methodology of the authors, not only reveals chromatin loss but permits important conclusions in regard to the proliferative state of the bone marrow and the specific time of action of the mutagens in the cell cycle. If arrest of the cell cycle occurs, as in the case of anti-metabolites MTX and 5-FU particularly, the routine scheme of investigation needs to be modified since micronucleated cells appear only after release of the metabolic block, i.e. after a delay of 24 h. The negative bone marrow results obtained with BM emphasize the importance of combining in vivo and in vitro tests.
| 64,925
|
Cytogenetic analysis of human chromosomes and its value for the estimation of genetic risk.
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A short review of present-day contradictory opinions on the usefulness of human chromosomal analysis in the system of chemical mutagen testing is illustrated by examples of the results achieved by both conventional and banding techniques. The results include exposures of human chromosomes to ECHH and TEPA in vitro, and to ECHH, vinyl chloride and Imuran in vivo. Exposures of human lymphocytes in vitro to the chemical to be tested for mutagenicity are recommended as one of the tests to be included in the system of mutagenicity testing, parallel with all other tests on mammalian and submammalian levels. The testing of human chromosomes of people exposed to chemicals in vivo is considered essential.
| 64,926
|
Rates, sample sizes, and the neutrality hypothesis for electrophoresis in evolutionary studies.
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It is shown that electrophoretic genetic distance estimates are highly correlated with albumin immunological distances between the same pairs of species. The bimodality of rates of electrophoretic differentiation at various loci is then documented and the electrophoretic clocks involved are calibrated. The differences between the systematics and population genetics uses of electrophoretic data are then discussed. Finally, a direct electrophoretic test of the neutral alleles hypothesis is presented and exemplified on a set of Thomomys bottae-umbrinus data.
| 64,931
|
An appraisal of symptom relief after coronary bypass grafting.
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Subjective symptomatic improvement is experienced by 90% of patients after coronary bypass surgery. Objective exercise testing reduces this incidence to 70%. An analysis of the multifactorial genesis of pain relief based on data of non-randomized trials reveals that graft patency plays a dominant but not unique role in causing improved symptomatology. In a number of cases, intra-operative myocardial infarctions seem to explain the pain relief but may also have opposite effects. Changes in left ventricular function operate bidirectionally but data on this variable in relation to changes in symptomatology are not amenable for detailed analysis. Progression in native vessel lesions apparently opposes pain relief and has its greatest impact in connection with graft closure. Residual post-operative angina is evidently related also to incomplete revascularization.
| 64,978
|
Albumin phylogeny for clawed frogs (Xenopus).
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Comparisons of albumin indicate that the frogs commonly used by North American molecular and developmental biologists under the name of Xenopus muelleri belong to another species, X. borealis. Phylogenetic analysis of the albumin data reveals two major groups of Xenopus species, one containing only X. tropicalis and the other, called the X. laevis grou, containing the remaining species of the genus. The phylogenetic tree, in conjunction with evidence from chromosomes and DNA content, leads to the hypothesis that total genome duplication occurred in the common ancestor of the X. laevis group.
| 65,013
|
Cell mediated lympholysis in man: an attempt to type with cytotoxic lymphocytes.
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From approximately 3,000 CML combinations, originally established in order to evaluate the qualitative and quantitative influence of the serologically defined HLA-A, B, and C antigens on cellular, complement independent cytolysis, 12 combinations were selected yielding reproducible positive cytolysis on allogenic target cells, although no HLA-antigenic sharing could be demonstrated between stimulator and target lymphocytes. These 12 CytoToxic Lymphocytes (CTL's) have been tested in parallell as "CML typing combinations" against lymphocytes from a random population sample of 100 unrelated Danes. Based on a pairwise analysis 11 of these CTL's could be classified into two groups of significantly correlated CTL's. These two groups do not define monospecific traits of allelic genetic origin as judged by a mutually positive correlation and a poor fit to Hardy-Weinberg equilibrium. The traits defined by these groups may be either partially identical or governed by closely linked loci. The same groups were identified and the same conclusions reached after exclusion of those individuals in the population sample where HLA-A, B, C, or D antigens may be targets for destruction. Thus, this study gives direct evidence that known HLA antigens are not sole target determinants in CML or that cytotoxic lymphocytes recognize HLA molecules in a different way than lymphocytotoxic antibodies. The studies underline the immunogenetic complexity of CML although this reaction is most probably governed by genes in the HLA region. It is suggested that cytotoxic lymphocytes may recognize "backbone structures" of the HLA molecules.
| 65,022
|
[Effect of Filatov's tissue preparation and and a globulin preparation on weight gain in calves].
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A comparitive experiment was carried out with 81 calves, aged 4-15 days, to establish the effect of a tissue preparation of swine embryos after Filatov, colostral lactoplasmin, and bovine gammaglobulin as prophylactic and therapeutic means, on the sera proteins. It was found that these preparations show no influence on the protein fraction ratio. It has also been pointed out that these agents produce a strong stimulative effect on the average daily weight gain of calves up to the sixtieth day following treatment.
| 65,047
|
Adenylate energy charge and the steroid 11 alfa-hydroxylase activity in Monosporium olivaceum during growth and starvation.
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During growth of Monosporium olivaceum its energy charge, E.C., (i.e. the adenylates ratio ATP + 0.5 ADP/ATP + ADP + AMP) increased from an initial value of 0.59 up to 0.85 after 25 hr of growth and then decreased to 0.51. The increase of energy charge was followed by the decrease of the activity of the 11 alpha-hydroxylase of cortexolone. This occured very clearly in the starved mycelium. Highest hydroxylation activity was observed when the lowest E.C. level (0.39-0.33) was reached.
| 65,105
|
Physiology and characterization of a fungal milk-clotting enzyme from Aspergillus flavus.
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Aspergillus flavus produced extracellularly an active rennin-like enzyme when grown aerobically in whey media. The enzyme was detected at early stages of growth reaching a maximum after three to four days at 25 degrees. The activity was destroyed by heating to temperatures higher than 50 degrees, whereas the presence of skim milk during heating preserved the enzyme activity, at least, up to 70 degrees. Calcium chloride significantly stimulated the milk-clotting activity up to 1% final concentration. The clotting time was inversely proportional to protein concentration in the range 0.2-0.6 mg/ml and the enzyme exhibited marked stability when stored at 37 degrees at pH 6.
| 65,107
|
[Hydroxy-ethyl-starch as plasma substitute in transurethral prostatectomy with the "cold-punch" method (author's transl)].
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Each of 24 patients undergoing transurethral prostatectomy under spinal anaesthesia received 1000 ml HES and, depending from the clinical situation, some patients received blood-transfusion. Afterwards two groups were formed: group A (11 patients), who received HES only, and group B (13 Patients) with additional blood-transfusions. The following parameters were monitored simultaneously: blood pressure, heart rate, stroke index, cardiac output, active blood volume, hemoglobin and hematocrit in whole blood as well as in the irrigatin fluid of the bladder. They showed HES to be a useful plasma substitute for older patients. It is well tolerated and has a slow stabilising effect on circulation, which was effective for several hours. Furthermore, HES-infusion reduced the average need of bloodtransfusion by 500 ml.
| 65,133
|
Immunological comparison of enzymes of the beta-ketoadipate pathway.
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beta-Carboxy-cis,cis-muconate lactonizing enzyme and gamma-carboxymuconolactone decarboxylase catalyze sequential reactions in the beta-ketoadipate pathway; the subunit sizes of the enzymes from Pseudomonas putida, biotype A, are 40 000 and 13 000, respectively. The cross reaction of antisera prepared against the enzymes was tested with the isofunctional enzymes formed by representatives of other bacterial species. Despite the differences in the subunit sizes of the enzymes, the antisera revealed the same general pattern: cross reaction was observed with the corresponding enzymes formed by other strains in the fluorescent Pseudomonas RNA homology group I and generally was not observed with enzymes from other Pseudomonas species or from other bacterial genera. Exceptions were provided by representatives of Pseudomonas cepacia. Members of this species are classified outside the fluorescent Pseudomonas RNA homology group. Nevertheless, the gamma-carboxymuconolactone decarboxylases from these organisms formed precipitin bands with antisera prepared against the corresponding enzyme from P.putida, biotype A; the lactonizing enzymes from the two species did not appear to cross react. Immunodiffusion experiments with gamma-carboxymuconolactone decarboxylase indicated that a common set of antigenic determinants for the enzyme is conserved among strains that have been classified together by other criteria; the relative immunological distances of the decarboxylases of each taxon from the reference P.putida, biotype A, enzyme were indicated by spurring patterns on Ouchterlony plates. These results suggested that the interspecific transfer of the structural gene for the enzyme is not a common event in Pseudomonas.
| 65,161
|
Heterologous specificity of reticulin RS antibodies.
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Reticulin antibodies were detected by the indirect immunofluorescence technique in 1450 sera from miscellaneous patients. R1 pattern on human and rat tissues was found only in 2 cases with adult coeliac disease. Reticulin Rs staining, involving intrasinusoidal cells of rat liver as well as interstitial and endothelial structures of various rat tissues, was demonstrated in 3.7% of cases, without correlation with gastro-intestinal or skin disorders. Rs pattern, due to IgG antibodies, could be absorbed by rat erythrocytes. Only Rs positive sera showed high titres of anti-rat IgG-type hemoagglutinins. Rat RBC agglutinating activity was demonstrated by a modified indirect Coomb's test. Heterologous Rs antibodies appear unrelated to particular diseases and should not be mistaken for the R1 and R2 patterns, which may be useful for diagnostic procedures.
| 65,175
|
Antigens in human glioblastomas and meningiomas: Search for tumour and onco-foetal antigens. Estimation of S-100 and GFA protein.
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Extracts of glioblastomas and meningiomas were analysed by quantitative immunoelectrophoresis for the presence of foetal brain antigens and tumour-associated antigens, and levels of 2 normal brain-specific proteins were also determined. The following antibodies were used: monospecific anti-S-100 (glia specific); monospecific anti-GFA (glial fibrillary acidic protein), (astroglia specific); polyspecific anti-foetal brain (12-16th week of gestation); a polyspecific anti-glioblastoma antiserum, absorbed with insolubilized serum, haemolysate and normal brain extract; polyspecific anti-alpha-foetoprotein; and monospecific anti-ferritin. Using the antibodies raised against the tumours, several antigens not present in foetal or adult normal brain were found in the glioblastomas and the meningiomas. These antigens cross-reacted with antigens present in normal liver and were therefore not tumour-associated. S-100 was found in glioblastomas in approximately one tenth the amount in whole brain homogenate, whereas GFA was found 2-4 times enriched. The 2 proteins were absent in meningiomas. The possible use of the GFA protein as a marker for astroglial neoplasia is discussed. Five foetal antigens were found in foetal brain, but none in the tumours. alpha-Foetoprotein could only be demonstrated in foetal tissue extracts, including foetal brain, but not in tumours. Ferritin was detected in all tumour extracts, although the amounts determined were unrelated to histological tumour type.
| 65,176
|
Reaction of peptide 89-169 of bovine myelin basic protein with 2-(2-nitrophenylsulfenyl)-3-methyl-3'-bromoindolenine.
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The C-terminal half of the bovine myelin basic protein, peptide 89-169, was treated with BNPS-skatole [2-(2-nitrophenylsulfenyl)-3-methyl-3'-bromoindolenine], and the products were isolated by repeated gel filtration through Sephadex G-50. They consisted of uncleaved peptide 89-169 in which approximately 30% of the tyrosine had been monobrominated and the tryptophan converted to oxindolealanine, peptide 116-169 modified by partial bromination (30%) of the tyrosine, and two chromatographic forms of peptide 89-115. The major form contained the lactone of dioxindolealanine at the C terminus; the minor form contained the uncyclized oxidation product. Each form of peptide 89-115 was resolved into several components by electrophoresis in polyacrylamide gels (10%, w/w) containing 1 M acetic acid and 8 M urea. The presence of three of these components could be explained by partial deamidation of Asn-91 and Gln-102. Studies on the oxidation of tryptophan-containing model peptides by BNPS-skatole indicated that the reaction can also include partial bromination of the dioxindole and its lactone and partial cleavage at the amino peptide bond of the tryptophan.
| 65,177
|
Cytochemical aspects of Mercenaria mercenaria hemocytes.
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The hemocytes of the hard clam M. mercenaria were of three types: an agranulocyte, a small, and a large granulocyte. The agranulocyte, with only a thin periphery of cytoplasm surrounding the nucleus, had no visible cytoplasmic granules in living preparations but did exhibit a few centers of nonspecific esterase activity. This cell type represented 2% of the hemocyte population. The small granulocyte possessed four distinct granule types and comprised 61% of the total cell population. Large granulocytes accounted fro 37% of all hemocytes. While they contained the same four granule types identified in the small granulocyte, only one-third the total number were present. The nucleus of all three hemocyte types appeared morphologically similar. The four types of granules observed were a blunt, dot-like, a refractile and a filamentous granule. Blunt granules were identified as mitochondria, based on their ability to reduce Janus Green B to diethyl safranin, the presence of NADH dehydrogenase activity and boundary staining with Sudan black B. Dot-like granules were identified as lysosomes on the basis of neutral red staining, localization of acid phosphatase and nonspecific esterase activity and staining with Sudan black B. Refractile granules were demonstrated to be membrane-bound, lipid-filled structures that reacted positively with Sudan black B and Oil red O, respectively; these granules act as lipid storage centers. Nuclear similarity of the three cell types suggest that these cells might represent different stages of maturity, rather than three distinct cell lines. This was also indicated by the similar yet graded cytochemical reactions and the varying degree of motility and phagocytic activity demonstrated by hemocyte types.
| 65,187
|
The place of radiation therapy in the treatment of non-Hodgkin's lymphomas.
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The use of Hodgkin's disease as a model for the evaluation and management of the non-Hodgkin's lymphomas may not be appropriate. This latter group of different syndromes and diseases differs significantly in their clinical presentation from each other as well as from Hodgkin's disease. Survival must be separated from relapse-free survival since the latter is a measure of the effectiveness of any individual therapy being applied. Localized nodal lymphoma is uncommon, but important to identify since it is potentially curable by irradiation. Stage I nodular, non-histiocytic lymphomas treated by radiation results in significant, extended, relapse-free survival. All other localized nodal lymphoma is associated with a high proportion of patients relapsing outside the treatment portal. Whole body irradiation is a useful systemic agent causing regression for an extended period of time in stage III or stage IV nodular lymphoma. Chemotherapy seems to have a limited value in nodular lymphomas, with no clear evidence that combination chemotherapy is more effective than single agents. In diffuse lymphomas, aggressive chemotherapy shows more promise, with diffuse histiocytic lymphoma having extended relapse-free survival.
| 65,208
|
Eight-drug combination chemotherapy (MOPP and ABDV) and local radiotherapy for advanced Hodgkin's Disease.
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Thirty-seven patients with advanced Hodgkin's disease have been treated for greater than or equal to 3 months with a protocol consisting of alternate monthly courses of MOPP (mechlorethamine, Oncovin [vincristine], procarbazine, and prednisone) and ABDV (adriamycin, bleomycin, DTIC, and vinblastine) with local radiotherapy (RT) to areas of originally bulky disease. This therapy produced CR in 19 of 19 previously untreated patients (100%), eight of nine previously treated with RT (89%), and six of nine previously treated with RT and MOPP (67%). The remaining patients are all PRs tending toward CR status. The median time to CR was 3.0 months. The median time in remission to date for the previously untreated patients is 8+ months (2+-14+). After an induction period of eight cycles of chemotherapy patients are maintained on alternate-month treatment continuing the alternating sequence. During this phase three patients have experienced reappearance of disease (one recurrence, one possible second primary lymphoma, and one recurrence in a patient whose original diagnosis is in doubt). The regimen has been well tolerated. All patients were treated as outpatients. Alopecia and neurotoxicity were mild and myelosuppression was moderate. Clinically significant cardiopulmonary toxicity has been limited to mild radiation pneumonitis in one patient and bleomycin pneumonitis which cleared during prednisone in a second patient.
| 65,221
|
Ultrastructural studies on the secretory cycle of the neurosecretory cells and the formation of Herring bodies in the paraventricular nucleus of the rat.
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The ultrastructure of the neurosecretory cells in the paraventricular nucleus of the normal male rat was studied by electron microscopy during various functional states. Four morphologically distinct types of neurosecretory cells were observed. It appears that they do not represent different classes of cells but different phases of secretory activity of a single cell type. The perikarya of the neurosecretory cells show a definite cycle of formation and transportation of secretory granules. We have designated the phases of this cycle as: (1) phase of synthesis, (2) phase of granule production, (3) phase of granule storage and (4) phase of granule transport. The neurosecretory granules appear to be moved in bulk into the axons, forming a large axonal swelling filled with granules as a result of one cycle in the neurosecretory process. Thus it may be postulated that a secretory cycle in the perikaryon of the neurosecretory cell seems to result in the formation of a Herring body in its axon, and that its content is then conveyed to the posterior pituitary.
| 65,228
|
Further evidence for the existence of intralobular nerves in the rat liver.
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In a recent study (Skaaring and Bierring, 1976) we found cholinesterase-positive nerve-like structures in the lobules of rat liver, and scanning electron microscopy revealed cords having a distribution pattern similar to that of the cholinesterase-positive structures. To obtain further evidence for an intralobular nerve supply the methods of cobalt and Procion Yellow nerve staining (Stretton and Kravitz, 1968; Iles and Mulloney, 1971; Pitman, Tweedle and Cohen, 1972) were adapted, iontophoretic introduction of the dyes being attempted through cut axonal ends in the surface of small excised blocks of rat liver.
| 65,229
|
Hippocampal RSA (theta), apnea, bradycardia and effects of atropine during underwater swimming in the rat.
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Hippocampal RSA (theta), neocortical EEG, and heart rate were recorded during surface and underwater swimming in the rat. RSA was present with slightly reduced frequency during the apnea, bradycardia, and vibrissae arrest associated with under water swimming. Atropine sulfate (50 mg/kg) blocked bradycardia did not affect RSA. Contrary to previous suggestions, no causal relation was found between RSA and respiration, heart rate, or vibrissae movement. The study supports the view that RSA is related to the neural control of voluntary movement. It is suggested that the slight reduction in RSA frequency during underwater swimming may be part of an oxygen conservation process.
| 65,274
|
Organization of sequences of avian globin mRNA.
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Formamide polyacrylamide gel electrophoresis shows that chicken globin mRNA contains about 6.50 nucleotides, and since only 435 of these code for globin, a further 215 are not translated, and their function and position are not known. This work has produced the following conclusions. 1. 45-50 of these untranslated nucleotides are present as poly (A) at the 3' terminus. 2. The 3' untranslated region of chicken globin mRNA is at least 90 nucleotides in length. This minimal estimate is based on data derived from hybridization of defined lenghts of chicken globin cDNA to rabbit globin mRNA. The percentage of avian globin cDNA sequences which hybridize to rabbit globin mRNA is directly proportional to the length of the cDNA in each case. This relationship holds for lengths of cDNA from 115 up to 620 nucleotides. The low percentage homology for short cDNA molecules is not due to their being short per se. In homologous mRNA excess hybridizations (chicken cDNA/chicken mRNA), all cDNA preparations were completely protected from S1 nuclease digestion. 3. It is probable that there is greater evolutionary divergence in the 3' untranslated region of chicken and rabbit globin mRNA when compared with the coding regions of these molecules; The combined data is sued to formulate a regional map of chicken globin mRNA,
| 65,281
|
Argyrophilic cells in the larynx of the guinea-pig demonstrated by the method of Grimelius.
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Argyrophilic cells with branching processes are shown in both the surface epithelium and in the glands in the larynx of adult guinea-pigs using the Grimelius silver technique after GPA fixation. When Bouin's fixative or neutral formalin were used as fixatives argrophilic cells could not be identified.
| 65,349
|
Study of the pituitary-thyroid functions at high altitude in man.
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The alterations in serum levels of T3, T4, TSH and TBG, TSH response to 100 mug iv TRH, and urinary excretion of T3 and T4 were studied in 8 healthy men at sea level (SL), on days 1, 2, 4, 8 and 16 after arrival by air at high altitude (3,700 m, HA), and during days 5 to 7 after their return to SL. No significant alterations in serum levels of TSH and TBG or TSH response to TRH were observed during exposure to HA or on return to SL. There was, however, an acute elevation in both serum total T3 and T4. Serum total T3 from a mean basal+/-SE value of 128+/-13 ng/dl increased to 320+/-18 on day 1 and remained significantly elevated at 225+/-48 up to day 8 after arrival at high altitude. Similarly serum total T4 increased from basal level of 9+/-0.92 mug/dl to 15.2+/-1.2 and remained elevated till day 16 and it was 11+/-1.19 mug/dl during days 5 to 7 after return to SL. The urinary excretion of both T3 and T4 was decreased. These changes perhaps were the result of complex physiologic adjustments on acute exposure to high altitude, like shrinkage of the T3 and T4 distribution pools, altered binding capacities of thyroid hormones binding proteins, and a reduction in clearance of thyroid hormones from the plasma compartment; and were probably not suggestive of an enhanced thyroid activity. Their actual significance in high altitude adaptation in man is not clearly understood.
| 65,358
|
The organization of the facial nucleus of the brush-tailed possum (Trichosurus vulpecula).
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The facial nucleus of the brush-tailed possum has been studied using Nissl staining and the horseradish peroxidase (HRP) retrograde tracing technique. In Nissl stained sections the nucleus is seen to comprise five distinct subnuclei. Injections of HRP into individual facial muscle groups have shown that these subnuclei reflect the peripheral innervation pattern of efferents from this nucleus. Although in most cases, injection of HRP into a single facial muscle group resulted in the labelling of neurons in more than one facial subnucleus, the following subnuclei were most completely labelled subsequent to intramuscular injection of HRP: the dorsal intermediate subnucleus was labelled with HRP reaction product following injection of m. auricularis anterior; the middle intermediate subnucleus was labelled following injection of the muscle underlying the malar vibrissae; the ventral intermediate subnucleus was labelled following injection of the m. mentalis; the medial subnucleus was labelled following injection of the m. auricularis posterior; the lateral subnucleus was labelled following injection of the m. nasolabialis with HRP. In general there is a mediolateral representation in the facial nucleus of neurons innervating facial muscle groups which are found in anteroposterior succession along the head of the animal. Muscle groups found in dorsoventral succession on the animal are represented dorsoventrally in the facial nucleus.
| 65,363
|
Temperature and acid concentration in the search for optimum Feulgen hydrolysis conditions.
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Exposure and removal of aldehyde groups during Feulgen acid hydrolysis were studied at a wide range of temperature and acid concentrations. Temperatures between 9 and 75degreesC were found to influence only the rate of the hydrolysis reaction over the entire range from high (6 M) to low (0.05 M) HCl concentrations. The temperature dependence was high, and around +5degreesC was sufficient to double the reaction rate. The influence of acid concentrations between 0.02 and 6 M was studied, and the extraction rates that determine the peak values of the Feulgen hydrolysis curve were found to depend in the same way on the (H+) concentration. A diagram is given that makes it possible to determine the time to reach the point during hydrolysis where the maximum amount of aldehyde groups are developed for a wide range of temperatures and acid concentrations. Temperatures slightly above room temperature in combination with high acid concentration is recommended for Feulgen hydrolysis.
| 65,418
|
Antigen recognition: the specificity of an isolated T lymphocyte population.
|
Guinea pig lymph node lymphocytes were separated into T and B cell fractions on immunoabsorbent columns. Separated cells were functionally distinct: T cells proliferated in response to ConA, PHA, soluble and alloantigen, whereas anti-Ig reagents only stimulated B cells. The in vitro proliferative response of guinea pig lymph node T lymphocytes was then shown to be highly discriminating when elicited by a series of structurally similar synthetic DNP-oligolysine antigens. Proliferation was always most extensive in response to the homologous, immunizing antigen, and less intense to cross-reacting DNP-oligolysines. Specificity of proliferation was maintained in the absence of both B lymphocytes and antibody secreting cells, suggesting that T cell recognition is not "acquired" from B cells or secreted antibody, but is a property inherent to the T cell.
| 65,426
|
An antigenic subunit present in rotavirus infected faeces.
|
It has been found by immune electron microscopy that rotavirus-infected faeces, calf or human, contain an antigenic subunit associated with the inner of the two virus capsids. This internal component represents the group specific antigen for the rotavirus group and the subunit reacts with both homologous and heterologous antiserum. It can therefore be used in diagnostic tests and in this paper its use as a reagent for immunodiffusion is described.
| 65,444
|
Intensive immunosuppression with cyclophosphamide in multiple sclerosis. Follow up of 110 patients for 2-6 years.
|
140 MS patients were treated with intensive I.V. cyclophosphamide immunotherapy and 110 were followed over 2-4 years. Annual relapse rate incidence was calculated over a period of 2 years before and after treatment and repeated neurological scores were made during this period. The conclusions are that 62% of the patients were stabilized during 2-4 years and that clinical improvement of the neurological signs was observed in most of the cases. It is concluded that intensive immunosuppression is able to interfere with the pathological processes involved in the pathogenesis of disseminated sclerosis.
| 65,452
|
Comparison of radiolabeled bleomycins and gallium citrate in tumor-bearing mice.
|
Radioiodinated bleomycin is a chemically stable radiopharmaceutical that can be prepared with high specific activity using 123I. Its pharmacokinetics were compared with those of 99mTc,- 111In-, and 57Co-bleomycin, and 67Ga citrate in mice bearing a transplanted KHJJ tumor. The in vivo kinetics and stability of 123I- and 57Co-bleomycin were similar: both were acceptable, although not equivalent, tags for bleomycin and, along with 67Ga citrate, both had biologic properties suitable for tumor detection. Both 99mTc- and 111In-bleomycin dissociated rapidly in vivo and hence do not represent legitimate tags for bleomycin. However, 111In-bleomycin may have tumor-localizing properties related to its biochemical properties after the indium and chelate separate in vivo. Iodine-123 is superior to either 57Co or 55Co. Tumor-to-blood and tumor-to-liver ratios were higher for I-bleomycin than for 67Ga or Co-bleomycin. The nearly ideal nuclear properties of 123I should complement the biologic properties of bleomycin and lead to a useful tumor radiodiagnostic agent.
| 65,460
|
Hyalin material bounding dystrophic calcification in the epithelial lining of odontogenic cysts.
|
Areas of dystrophic calcification present in the epithelial lining of two apical periodontal cysts have been shown to exhibit an outer layer of hyalin material. Similar calcific areas in the connective tissue walls do not show hyalin boundaries. Hyalin material has been found around muscle fibers present in the epithelial lining of a residual dental cyst. It is believed that the hyalin material is secreted by the epithelial cells and these observations are considered to be supporting evidence that hyalin bodied arise as an epithelial secretion.
| 65,463
|
Prevention of Fatal Postoperative pulmonary embolism by low doses of heparin. Reappraisal of results of international multicentre trial.
|
The results of a multicentre trial, designed to assess the efficacy of low-dose heparin in preventing fatal postoperative pulmonary embolism, were published in July 1975. In view of inconsistencies which have now become apparent in the data from one of the twenty-eight centres which took part in the trial, the results of the trial have been re-examined, excluding the data from this centre. Of 4031 patients remaining after exclusion of these data, 2033 were in the control group and 1998 in the heparin group. 170 (4-2%) patients died during the postoperative period, 94 in the control group and 76 in the heparin group; 70-2% of deaths in the control group and 65-7% in the heparin group had necropsy examination. 15 patients in the control group and none in the heparin group were found at necropsy to have died due to acute massive fatal pulmonary embolism (P less than 0-001). Exclusion of data from the one centre did not alter already published significant differences in the total incidence of deep-vein thrombosis, nor in the frequency of operative and post-operative bleeding complications observed in the control group and the heparin group.
| 65,660
|
A fluorescence staining method for the examination of microorganisms on natural substrates.
|
A fluorescence staining technique is described which uses the magnesium salt of 1-anilino-8-naphthalene sulfonic acid as a protein stain. At a concentration of 2.5 or 3.0 mg ml-1 in distilled water or phosphate buffer the compound does not fluoresce under ultra-violet or far blue illumination until it is bound to a protein or similar compound. It can be applied to natural substrates such as soil, food materials, organic material in water, etc., and can be examined immediately without any washing procedures. The application of this staining method to detect microorganisms on dead green algae (detritus) is described.
| 65,720
|
Chemical modification of DNA polymerase phosphoprotein from avian myeloblastosis virus.
|
Fractionation of purified avian myeloblastosis virus DNA polymerase, after phosphorylation in vitro, revealed the presence of a small acidic proten, a phosphate acceptor polypeptide with high specific activity. Its presence in the phosphorylated form with the polymerase resulted in as much as a 10-fold increase in the rate of DNA synthesis. Its presence in the dephosphorylated form with the polymerase had no effect in the rate of DNA synthesis.
| 65,734
|
[Evaluation of the relations between serum proteins electrophoresis and other laboratory tests in monoclonal gammopathies (author's transl)].
|
We have considered interesting to determine monoclonal gammopathies incidence, in 2191 serum proteins electrophoresis performed in our laboratory from January to December 1974. We have found 15 cases of monoclonal gammopathies, some cases combined with Mieloma (3 cases), some other with other with non specific diseases. We have considered the relations between type of gammopathy and other laboratory tests useful for any other diagnose: they are: immunochemical analysis, E.S.R., red and white count, total proteins, Bence Jones protein.
| 65,779
|
[Is there any bimodality of the age distribution of male mammary cancer (author's transl)?].
|
The authors study the pattern of the curve concerning breast cancer incidence in males as a function of age. The demonstration is made that such a curve is bimodal and, more precisely, could be satisfactorily considered as being made up of the juxtaposition of two normal distribution curves. The interval thus individualized between the mean age of both groups is remarkably steady between 17 and 20 yrs. The phenomenon is not blurred by regrouping the data and the patients population could be divided into two subgroups: one with a mean age of 147 yrs, with a standard deviation of 9 yrs, and bearing on 246 patients, the other one including 1.100 patients averaging 66.5 yrs old with a standard deviation of 9.9 yrs.
| 65,784
|
[A vertebral body implant for use in palliative surgery of spinal tumors (author's transl)].
|
A newly developed vertebral body implant is discussed which is used to support and stabilize the spine after surgical removal of a vertebra in spinal tumors.
| 65,845
|
[The influence of zink and lead on the formation of antibodies (author's transl)].
|
Female NMRI-mice were injected intraperitoneally and subcutaneously with zinc chloride and lead chloride as well as with a mixture of both. The mice were also immunized with foreign-proteins. To demonstrate the interconections, the heavy metals and the proteins were injected separately, as was the heavy-metal-protein-suspension. The results of the studies are as follows: 1. Intraperitoneal application of lead leads to a significant elevation of the antibody titer, using bovine immunglobuline while zinc applications showed no rise or slightly raised antibody formation. 2. It could be demonstrated that the admixtion of zinc chloride depresses the stimulatory effect of lead chloride on the immunization. 3. With the heavy metal-protein-mixture is proved that lead chloride stimulates the antibody production more than zinc chloride. To explain these results, it is discussed whether the adjuvant effect of lead is inhibited by zinc whereas zinc itself stimulates the immunsystem through another working mechanism.
| 65,877
|
Effect of encephalitogenic protein on migration in agarose of leukocytes from patients with multiple sclerosis. Variable effect of the antigen in a large dose range, with a literature review.
|
The literature on in vitro test of sensitivity to brain antigen in multiple sclerosis is summarized in the tables. A study is presented using leukocyte migration in agarose as test system and a wide range of concentration of bovine encephalitogenic protein as antigen. Definite reactivity was seen in 12 out of 28 patients with MS. Some occurred in patients who had had no signs of disease activity for at least 5 years. Reactivity occurred more often in patients with active disease studied within 5 days after a relapse. The significance of the in vitro reactivity is briefly discussed.
| 65,893
|
Molecular interactions in human atherosclerotic plaques.
|
Most plasma proteins appear to be present in intima at concentrations that are a linear function of molecular weight and concentration in the plasma. Thus low density lipoprotein (LDL) (molecular weight, 2 X 10(6)) has the greatest retention relative to its plasma concentration, whereas the relative retention of albumin is only 15% of the relative retention of LDL. This gives rise to the concept that "whole plasma" crosses endothelium, and the steady state concentrations reflect rates of egress of the macromolecules, which in turn depend on molecular sieving. Fibrinogen is a major plasma protein in intima in addition to LDL and albumin, and there are also substantial amounts of the protease inhibitors alpha2-macroglobulin and alpha1-antitrypsin. Intima also contains insoluble derivatives of plasma--extracellular cholesterol, both free and esterified, and fibrin. The balances of intact LDL/"deposited" cholesterol and of fibrinogen/fibrin are closely linked with intimal morphology. Fibrinogen and electrophoretically mobile LDL are increased about threefold in gelatinous lesions, whereas there are only slight rises in fibrin and deposited cholesterol. In the deep layers of fibrous plaques, fibrin is increased fivefold and cholesterol up to thirtyfold. In these lipid-rich layers, LDL is rapidly lost on incubation of tissue samples, but in some gelatinous lesions it first increases and only decreases on longer incubation, suggesting release of a previously immobilized lipoprotein fraction. This immobilized lipoprotein was investigated by subjecting tissue samples to immunoelectrophoresis to remove mobile LDL and tissue enzymes, followed by treatment of the tissue with enzyme and measurement of the lipoprotein released on fresh immunoelectrophoresis plates. Plasmin or a crude collagenase released large amounts of lipoprotein from samples of amorphous atheroma lipid. For all samples the amount of lipoprotein released was highly correlated with the accumulation of deposited cholesterol, suggesting that immobilization of LDL may be an intermediate step in the irreversible deposition of extracellular cholesterol. Plasmin is highly effective in releasing immobilized lipoprotein, and the concentration of immobilized lipoprotein is significantly correlated with the concentration of insoluble fibrin, suggesting that the lipoprotein may in some way be immobilized by fibrin.
| 65,917
|
Further evidence for a central regulation of free fatty acid mobilization in the rat.
|
Previous studies have shown that anterior hypothalamic deafferentation in rats completely suppresses the increase in plasma free fatty acid (FFA), but not the hyperglycemia induced by administration of 2-deoxyglucose, suggesting a specific central regulation of FFA mobilization. The physiological importance of this finding was further investigated by examining in deafferented rats the response to several stimuli that modify the rate of lipomobilization in normal rats. The results show that the hypothalamic lesion interferes with FFA mobilization mainly when increased sympathetic activity is required: during cold exposure or forced muscular activity, and after insulin-induced hypoglycemia or a relatively long period of fasting. Changes in blood sugar responses, when observed, could be interpreted as secondary to an initial block in FFA mobilization. The data support our hypothesis that there are areas in the central nervous system sensitive to glycopenia and activated in situations requiring rapid mobilization of metabolic reserves that can specifically influence FFA mobilization through an activation of the sympathetic fibers of adipose tissue.
| 65,918
|
[Effect of prolonged glucidic starvation on the contents of starch and tannins of Blechnum brasiliense L. gametophytes].
|
Some Blechnum brasiliense gametophytes have been maintained in darkness, in a purely mineral medium, for the purpose of investigating the effect of prolonged glucidic starving on the amount of tannins and starch that they contain. During the first two months the tannin contents undergoes a fast decrease. The starch variations are different : a transitory increase simultaneous with the fall in tannin; a decrease after the disappearance of 3/4 of the tannin contents; and lastly, a new amylogenese which precedes the prothallus necrosis. It seems that the gametophytes, in order to survive, degrade first their tannoidic reserves, and they utilize the starch that they contain only with difficulty. This behaviour can be explained by the distribution of the two metabolites; by the acid pH of the medium, which is not very propitious to the phosphorylases activity and lastly by the presence of chlorogenic acids, which are inhibitors of those enzymes.
| 65,957
|
[Decrease in maximum consumption of oxygen after blockage of beta-andrenergic receptors].
|
VO2 max, maximum oxygen uptake, has been measured in 4 normal young men, before and after beta-adrenergic blockade (0.5 to 5 mg Pindolol by mouth). Pindolol induces bradycardia and reduces VO2 max. A statistically significant positive correlation appears between posology of Pindolol and bradycardia, this posology and reduction of VO2 max, and finally between bradycardia and reduction of VO2 max. These correlations indicate that the reduction of VO2 max is best explained by a circulatory limitation of oxygen supply to active muscles.
| 66,035
|
[Free amino acids in sera of Cymothoidae (crustacean, isopods, parasites of fishes) and some teleosts].
|
The free amino-acid composition of the sera of 4 species of Isopods Cymothoidae (Meinertia oestroides, Meinertia parallela, Emetha audouini, Anilocra physodes) are very similar, and present the same characteristics, both quantitatively and qualitatively, as those of free marine Isopods of the family Sphaeromatidae and Idoteidae. Five amino acids are preponderant (serin, prolin, glycin, alanin and taurin). The total concentration is relatively high (154.6-356.4 mg/100 ml) with respect to Decapods. In the parasites studied so far, the free amino-acid pattern (except prolin) is rather like that of the Teleost Fishes, whether they are potential hosts of Cymothoidae or not. The free amino-acid concentration of the blood of the Fishes does not seem to be impaired by the Cymothoidae parasitism.
| 66,040
|
[Free amino acids of hemolymph of marine isopods, Sphaeroma hookers Sphaeroma serratum (Flabellifera) and Idotea balthica (Valvifera)].
|
The total concentration of the free amino acids in the hemolymph is higher (about twice the amount in three species of marine Isopods (Sphaeroma hookeri, S. serratum and Idotea balthica) than in Decapods. In the three species so far studied, the proportions of glycine and taurine are always rather high. In the Sphaeromatidae, serine is the most concentrated amino acid while the proline concentration is comparatively low. The situation is reversed in Idotea balthica. In Crustaceans, the free amino acid composition of the hemolymph thus appears, both quantitatively and qualitatively, to be a biochemical character of marine Isopods when compared to Oniscoids Isopods and to Decapods.
| 66,041
|
Osmium dependent argentaffin reaction in the pancreatic islet.
|
By applying at the ultrastructural level the silver methenamine impregnation method to glutaraldehyde-osmium fixed pancreatic tissue of Snell-Bagg mice it was found that two islet cell types show deposition of reduced silver on their secretory granules: B cells and another cell type. Histochemical analyses indicate that very likely the osmium dependent argentaffinity is due to S-S groups. After alkaline treatment the reactivity of B cells is lost, while that of the other cells remains unaffected. It is suggested that the third cell type stores the pancreatic somatostatin, an S-S containing polypeptide hormone.
| 66,046
|
Pharmacodynamic actions of midodrine, a new alpha-adrenergic stimulating agent, and its main metabolite, ST 1059.
|
Pharmacodynamic actions of alpha-(2,5-dimethoxyphenyl)-beta-glycinamido-ethanol-hydrochloride (midodrine, Gutron) and alpha-(2,5-dimethoxy-phenyl)-beta-aminoethanol (ST 1059), the main metabolite of midodrine, were investigated in various experimental procedures. Midodrine raises arterial blood pressure both after parenteral and enteral administration in animal experiments. Midodrine increases peripheral vascular tone when given in doses still ineffective in raising blood pressure. The d(+)-isomer of midodrine is by far less effective than the racemic mixture. Pretreatment with atropine, reserpine, guanethidine or hexamethonium has no influence on midodrine activity. Midodrine effects are greatly reduced by phentolamine but rather enhanced by propranolol pretreatment. Midodrine raises blood pressure in pithed rats, too; in the experiments performed the drug is devoid of central effects even when high doses are given. Chronic pretreatment with midodrine over a longer period reduces the effect of a subsequent single injection of this substance. Because of the results cited above midodrine may be classified as a direct peripheral alpha-adrenergic stimulating agent. alpha-Adrenergic receptor stimulation induced by midodrine can be demonstrated in various smooth muscle organs (blood vessels, nictitating membrane, intestine, pupil, urinary bladder, bronchi). In contrast to other pressor sympathomimetic agents, midodrine is of long duration of action and good efficacy after enteral administration. ST 1059, the main metabolite of midodrine, is an active alpha-adrenergic stimulating agent with a shorter duration of action than midodrine. It is suggested that midodrine is the well-absorbed "transport form", from which ST 1059, the actural pressor agent, is formed enzymatically in organism.
| 66,056
|
[Properties and the protein composition of lymph and blood in burns].
|
Experiments conducted on 25 dogs demonstrated that burn was accompanied by a regular redistribution of plasma proteins between the fluid media of the organism and an intensification of lymphogenic resorption. Properdin, albumin, and alpha2-globulin retardation in tissues in case of burn was demonstrated indirectly. The degree of burn proved to depend on the initial properdin level.
| 66,073
|
Classification and audiovisuals.
|
The University of Connecticut Health Center Library's substantial investment in audiovisuals has prompted careful examination of its organization of the AV collection and its effectiveness in answering user needs. While an accession number system worked for a small collection, increased size quickly generated access problems, especially because shelves are open to users. With the present collection of over 2,500 audiovisual items, adoption of the NLM classification promises convenient and continued flexibility in the future.
| 66,078
|
Mean velocity of optically detected intraaxonal particles measured by a cross-correlation method.
|
A method which uses by the cross correlation of optical signals is described for the determination of the mean velocity of somatopetally moving particles within nerve fibers. The method was validated by simulation experiments and by comparing the results with those obtained by averaging collections of velocities of individual particles. The significant contribution of the method is that it allows objective and rapid serial evaluation of mean particle velocity within individual nerve fibers with good accuracy and precision. A series of results from normal myelinated nerve fibers from Xenopus laevis is presented. Considerable variation (up to 50%) in mean velocity was found between individual nerve fibers. The mean of all determinations indicates that the mean velocity of somatopetally moving particles in axons with diameters greater than 10mum is in the region of 1.14 mum/s at a temperature of 22-24 degrees C. The findings are compared with small collection of such determinations which have been reported in the literature.
| 66,091
|
Far field somatosensory potentials in the rat.
|
Averaged somatosensory evoked potentials (SEPs) in the rat were recorded from skull electrodes. The cortical component of the SEP was preceded by at least three low amplitude potentials. Surface distribution of these potentials, correlation with depth recording from posterior columns, posterior column nuclei, inferior cerebellar peduncle, medial lemniscus, ventral posterior thalamus and sensory radiation, and the effect of brain stem and medullospinal transections on these potentials showed that: (1) All potentials preceding the cortical SEP are far field reflections of activity generated at a distance from the site or recording. (2) Component I originates in posterior columns. (3) Component II reflects summated activities in posterior column nuclei and medial lemniscus. (4) Anterior component III reflects summated activities in the ventral posterior thalamus and sensory radiation. (5) Posterior component III probably reflects activities originating in cerebellar pathways and cerebellum.
| 66,129
|
New sphenoidal electrode assembly to permit long-term monitoring of the patient's ictal or interictal EEG.
|
A new sphenoidal wire electrode is described which greatly increases the clinical and diagnostic usefulness of sphenoidal electrode recordings. These very fine wire electrodes are easy to insert; they are comfortable and acceptable to the patient. In contrast to sphenoidal needle electrodes they expose the patient to no risk should he have a seizure during recording. These electrodes also allow one to extend the recording time to several days, thus increasing the chances of recording a spontaneous seizure, for instance while the patient's EEG is being recorded with a telemetry system. The extended recording time also allows for continuous automatic sampling of the interictal EEG over a period of several days. The quality and the reliability of the EEG record are also enhanced. The new sphenoidal electrodes have been used on over 100 patients and are now being used routinely on suspected temporal lobe epileptics recorded with conventional techniques, while 50 of the patients have also been recorded with a cable-telemetry seizure monitoring system which has captured 65 spontaneous seizures.
| 66,141
|
Immunoglobulin-like messenger RNA in a mouse T cell lymphoma.
|
RNA-driven complementary DNA (cDNA) hybridization experiments have been carried out in order to detect complementary sequences in RNA prepared from a mouse T cell lymphoma line (EL4). In conditions where efficient hybridization of L-chain cDNA with homologous P3 myeloma mRNA was observed, poor hybridization was observed with EL4 mRNA unless a low criterion of hybrid formation was employed (i.e. hydroxyapatite fractionation). The hybrid formed between EL4 mRNA and L-chain cDNA was found to melt about 5 degrees C below the homologous hybrid indicating that the sequence detected in EL4 mRNA is similar but not identical with the P3 mRNA sequence. However, a similar sequence was detectable in a Clambda-producing myeloma cell line but in this line the concentration of the sequence was found to be an order of magnitude lower than in EL4 cells.
| 66,149
|
The macrophage electrophoretic mobility test: Results on carcinoma of the colon and rectum.
|
The macrophage electrophoretic mobility (MEM) test was performed on guinea-pig macrophages treated with the interaction products of encephalitogenic protein and peripheral lymphocytes from 44 patients with colorectal cancer and 33 "healthy" controls. In 54/60 tests involving patients, statistically significant reductions in electrophoretic mobilities were observed, compared with 12/33 in controls. Our overall results on the reductions in macrophage mobilities by lymphocyte products are in accord with the work of some other workers, but not all. In contrast to many other studies, the standard procedures used here to express the results should permit an exchange of data on an international basis and allow a more rapid, general appraisal of the MEM test.
| 66,210
|
RNA-dependent DNA polymerase of avian sarcoma virus B77. I. Isolation and partial characterization of the alpha, beta2, and alphabeta forms of the enzyme.
|
Three forms of the RNA-dependent DNA polymerase were isolated from highly purified avian sarcoma virus B77 grown in duck embryo fibroblasts, using sequential chromatography on DEAE-cellulose, phosphocellulose, and poly(U)-cellulose. One form, which sedimented with about 5.2 S, contained only one species of polypeptide, with a molecular weight of 63,000; a second sedimented with about 7.8 S and contained only one species of polypeptide with a molecular weight of 81,000; and a third form, which sedimented with about 7.3 S, contained two species of polypeptides with molecular weights of 63,000 and 81,000. The molecular constitution of the three enzyme forms were therefore alpha, beta2, and alphabeta. All three possessed almost the same specific activity with poly(rA)-oligo(dT) as the primer-template. Forms alpha and alphabeta of avian sarcoma virus DNA polymerase have already been described in the literature; form beta2 is a new form. All three forms possessed ribonuclease H activity, the relative specific activities of the alpha, beta2, and alphabeta forms being about 1:4:5. All three enzyme forms were inhibited by antiserum to the alphabeta form, but whereas the alpha and alphabeta forms could be inhibited about 95%, the maximum degree of inhibition of the beta2 form was about 80%. The three enzyme forms also differed with respect to heat stability at 46 degrees, the monomeric alpha form of the enzyme being only about one-half as stable as the two dimeric forms.
| 66,234
|
Inhibition of the mixed lymphocyte culture response with anti-Lyb-4.1 serum 1,2,.
|
C57BL/Ks anti-L1210 serum, which recognized a non-H-2-linked B cell alloantigen, designated Lyb-4.1, specifically blocked the mixed lymphocyte culture (MLC) response to allogeneic cells that expressed the Lyb-4.1 determinant. Anti-Lyb-4,1 serum blocked the MLC response across H-2 and MLC disparities. To test that this effect was not the result of a toxic or nonspecific cell-coating action, the response of parental cells to F1 lymphocytes was studied in combinations in which only one parent expressed the recognized allele. MLC stimulation was blocked only when the responding parental cell recognized on the F1 cell H-2 or MLs disparities which were derived from the parent which possessed the Lyb-4.1 antigen. Several DBA/2 tumors were characterized by cytotoxic and quantitation absorption assays for the presence of the B cell antigen. The presence of the antigen correlated with the ability of a limited number of tumors to stimulate the MLC response of H-2d identical BALB/c lymphocytes. An increased representation of the B cell alloantigen was found on the transformed B lymphoblast cell line in comparison to splenic B lymphocytes.
| 66,278
|
Genetics of cell-mediated lympholysis in man.
|
Cell-mediated lympholysis (CML) was studied in a family containing two siblings in who genetic recombinaiton had occurred in the HLA comples. In one sibling, recombination occurred between the HLA-A locus and the HLA-B locus. In the second sibling recombination occurred between the HLA-B locus and the HLA-D locus. Strong CML activity was generated in mixed lymphocyte cultures (MLC) when stimulator and responder cells differed in HLA-A, B, and D antigens. MLC involving HLA-D differences alone did not generate CML. Weak, but definite CML activity was generated during MLC with cells differing at HLA-A and HLA-B but sharing HLA-D. HLA-B antigens were good targets for lysis in all combinations studied. HLA-A antigens were poor targets in some but not in all combinations. However, combinations where HLA-A antigens seemed to be good targets could have involved HLA-B differences due to polymorphism of HLA-B7 antigens each inherited from a different parent. HLA-D antigens did not serve as targets for lysis. In three cell experiments, excellent CML activity was generated when responder cells were stimulated by HLA-D antigens and by HLA-A and B antigens present on separate stimulator cells.
| 66,285
|
Antigen-binding lymphocytes in guinea pigs. I.B cell expansion to the monovalent antigen L-tyrosine-p-azophenyl trimethylammonium (tyr(TMA)) in the absence of antibody production.
|
The monofunctional antigen L-tyrosine-p-azophenyltrimethylammonium chloride, tyr(TMA), and the polyfunctional antigen, TMA-human gamma-globulin (TMA-HGG), were used to investigate the antigen structural requirements necessary for clonal proliferation of B cells. This clonal expansion was characterized with respect to receptor immunoglobulin class and affinity maturation. Antigen-binding analysis revealed that inoculation of tyr(TMA), although only of m.w. 344, triggers clonal expansion of B lymphocytes 9-fold in the absence of any apparent antibody production. There does not appear to be any maturation with respect to antibody class since greater than 90% of the tyr(TMA)-specific B cells bear the micron receptor in the nonimmune and immune state. However, the average avidity of the B cells for this antigen increases with time after immunization. In contrast, immunization with TMA-HGG results in an 18-fold increase in B lymphocytes with significant amounts of anti-TMA antibody production. With time after immunization, both maturation of average avidity and class of Ig receptor (micron leads to gamma shift) occur. These findings indicate that the functionally T cell-specific antigen tyr(TMA) can trigger clonal B cell expansion and affinity maturation at the receptor level in the absence of detectable antibody production.
| 66,287
|
Ionic selectivity, saturation and block in gramicidin A channels: I. Theory for the electrical properties of ion selective channels having two pairs of binding sites and multiple conductance states.
|
A model for the gramicidin A channel is proposed which extends existing models by adding a specific cationic binding site at each entrance to the channel. The binding of ions to these outer channel sites is assumed to shift the energy levels of the inner sites and barriers and thereby alter the channel conductance. The resulting properties are analyzed theoretically for the simplest case of two inner sites and a single energy barrier. This for-site model (two outer and two inner) predicts that the membrane potential at zero current (Uo) should be a Goldman-Hodgkin-Katz equation with concentration-dependent permeability ratios. The coefficients of the concentration-dependent terms are shown to be related to the peak energy shifts of the barrier and to the binding constants of the outer sites. The thory also predicts the channel conductance in symmetrical solutions to exhibit three limiting behaviors, from which the properties of the outer and inner sites can be characterized. In two-cation symmetrical mixtures the conductance as a function of mole fraction is shown to have a minimum, and the related phenomenon of inhibition and block exerted by one ion on the other is explained explicitly by the theory. These various phenomena, having ion interactions in a multiply occupied channel as a common physical basis, are all related (by the theory) through a set of measurable parameters describing the properties of the system.
| 66,317
|
Studies on an adrenal antigen common to man and different animals.
|
Precipitating adrenal antibodies, originally described by Andrada et al., are often associated with patients suffering from the moniliasis-polyendocrinopathy syndrome. The syndrome may include contemporarily several organ-specific autoimmune diseases such as hypoparathyroidism. Addison's disease, thyroiditis, pernicious anaemia, gastritis and ovarian failure and often combined with moniliasis and alopecia. These antibodies seem to differ from those demonstrable by immunofluorescence (IFL) and complement fixation. This conclusion was made as the titres of immunofluorescence antibodies did not correlate with the presence or absence of precipitating antibodies (Krohn et al., Clin Immunol Immunopathol 3:59-68, 1974; Heinonen et al., Ann Clin Res 8:262-265 1976). In this study we describe the subcellular localization and distribution of the precipitable adrenal antigens within some animal species. We found two precipitable adrenal antigens; one of them, designated P-antigen (particulate), was found in precipitable form only in the mitochondrial fractions, and the other, designated S-antigen, could be found in all subcellular fractions of some animal species. Bovine and equine S-antigen could be fractionated on a Sephadex G-200 column, revealing also the soluble nature of the S-antigen. The human S-antigen seemed to differ from the animal S-antigen as in addition to one common antigenic determinant (Sc), the human S contained a second determinant (Sh) not present in the animals. There was no difference in the antigenic character of the P-antigen within different species, although this conclusion is mainly based on the absorption studies.
| 66,422
|
Treatment of severe intermittent claudication by controlled defibrination.
|
Fifteen patients with severe intermittent claudication were treated by therapeutic defibrination with subcutaneous injections of ancrod for 5 weeks. Mean plasma-fibrinogen was maintained below 50% of the initial value throughout the treatment period. This reduction in plasma-fibrinogen was accompanied by a parallel fall in whole-blood viscosity and a pronounced clinical improvement. Objective measurements showed maximum benefit on the 21st day of treatment, when the mean resting ankle/arm pressure index had increased by 37%, the post-exercise pressure index had increased by 50%, and the time taken for the pressure index to return to a resting value after a constant exercise had decreased by 33%. (The claudication-count had increased by 59%).
| 66,429
|
Heart-rate variability in brain-damaged adults.
|
To test whether or not the characteristics of the adult heart-rate reflect the condition of the central nervous system (as they seem to do in the fetus), ten patients with neurological deficits of acute onset were studied. No patients had received drugs and none was hypoxic. The findings indicate that the normal cyclic changes in heart-rate are reduced in the presence of severe brain damage. Variability decreases rapidly if intracranial pressure rises, and the rate of return of variability reflects the subsequent state of neuronal function, even when intracranial pressure has been restored to normal. In this limited setting, then, it appears that heart-rate variability may reflect the functional state of the central nervous system.
| 66,430
|
Treatment of symptomatic diverticular disease with a high-fibre diet.
|
The therapeutic value of increasing the daily dietary fibre intake was assessed over 3 months in a double-blind controlled trial of 18 patients. Significantly greater symptomatic relief was obtained by those on a high fibre regimen than by those in the control group, despite a marked initial placebo effect. The effectiveness of a high-fibre diet increased over the 3-month period.
| 66,471
|
Cadmium and hypertension.
|
The cadmium concentration of renal tissue from 82 patients who had died at the age of 45-65 years has been determined by atomic absorption spectrophotometry; 43 were normotensive and 39 hypertensive. Renal cadmium concentration was higher in normotensives than in hypertensives. When smoking habits were taken into account, renal cadmium concentration was found to be 82% higher in normotensives than in hypertensives. Other workers have found the opposite relationship. It is proposed that this discrepancy might reflect either that variations due to age were not taken into account in previous investigations or that a difference exists between soft-water areas and hard-water areas such as the one studied.
| 66,476
|
[Distribution of certain enzymes in totally stained Cestode preparations].
|
The distribution of succinic dehydrogenase, HApi-diaphorase, glucose-6-phosphatdehydrogenase, alkaline and acid phosphatases and glucose-6-phosphatase was studied by means of the incubation of whole cestodes. Succinic dehydrogenase, NAD-diaphorase and glucose-6-phosphatdehydrogenase are connected in general with the fixating apparatus of the scolex and genital organs; phosphatases -- with the integument tissues, excretory system and calcareous corpuscles. The results obtained are in complete agreement with the available data on the distribution of the enzymes studied. The incubation method of whole cestodes can be useful for field works.
| 66,656
|
Expression of antigenic crossreactivity to RD114 p 30 protein in a human fibrosarcoma cell line.
|
An antigen crossreacting with the 30,000-molecular-weight protein (p30) of the feline endogenous oncornavirus (RD114) was detected in a well-characterized human fibrosarcoma cell line, HT1080, by indirect immunofluorescence. Three antisera against RD114 p30 gave similar positive results, while two antisera prepared against simian sarcoma virus p30, one antiserum prepared against murine leukemia virus p30, and one antiserum prepared against feline leukemia virus p30 gave no immunofluorescence. The reactivity observed with the antiserum against RD114 p30 was detected in 10-40% of the cells at early passages and was no longer expressed by the forty-first subculture. The reactivity could be removed by adsorption of the antiserum with RD114-infected dog or human cells, but not by uninfected cells or by cells infected with an antigenically unrelated oncornavirus, feline leukemia virus. Neither complete virus particles nor reverse transcriptase (RNA-dependent DNA nucleotidyltransferase) activity was detected in the culture. These experiments suggest that the fibrosarcoma cell line is expressing an antigen related to the p30 protein of RD114 baboon endogenous virus group of oncornaviruses without producing complete virions.
| 66,679
|
Histamine-releasing effect of a corticotrophin derivative. I. Histamine-releasing effect of a nonadecapeptide in comparison with that of other histamine liberators.
|
The histamine-liberating properties of a synthetic polypeptide (an a synthetic polypeptide (an alkylprolyl derivative of beta1-19-corticotrophin) were investigated under a variety of experimental conditions. It was found to be more potent in this respect than Compound 48/80, Melittin and Triton X-100. The degree of cell destruction observed in conjunction with the release of histamine induced by C 44 680-Ba suggests that the mode of action of the substance more closely resembles that of Compound 48/80 than that of Triton.
| 66,701
|
The absence of a human thymus lymphocyte antigen (HTLA) on basophils and mast cells.
|
Basophilic granulocytes and mast cells of different species have been reported to originate from thymocytes and other lymphocytes. These observations were recently confirmed when evidence was given that thymic antigen is present on rabbit basophilic granulocytes. In the study reported here, human leukocytes were tested by the immunofluorescence technique and the immunoelectron-microscopy technique to ascertain whether a human thymus lymphocyte antigen (HTLA) could be detected on their surface. We could demonstrate the presence of HTLA on T lymphocytes but not on basophilic granulocytes, nor on mast cells in Cryostat sections of various tissues.
| 66,740
|
Some characteristics of Mozambican Shangaans with primary hepatocellular cancer.
|
Certain characteristics of 328 Mozambican male Shangaans with primary hepatocellular cancer (PHC) have been compared with those of 163 Shangaan men with hepatomegaly from causes other than PHC and with those of 122 Black Southern African men with the same tumour but who belonged to tribes other than the Shangaan. Shangaans with PHC were significantly younger than non-Shangaans with the tumour (mean age 33,4 cf. 40,0 years; Pless than 0,001). They also had a significantly higher positivity rate of alpha-fetoprotein by immunodiffusion (71,4%) than the non-Shangaans (16%), although in other respects the tumours appeared to be similar. Cirrhosis of the non-tumorous part of the liver was present at necropsy in 62% of the Shangaans and in 66% of the non-Shangaans. The hepatitis B (surface) antigen (HBsAg) was detected in the serum of 60% of the Shangaans with PHC compared with only 9% of the controls. The antigen was present in 53,4% of the non-Shangaans with PHC (the difference between this fifure and that in the Shangaans was not significant). HBsAg was detected in the serum of 64% of the Shangaans with PHC and cirrhosis, but also in 74% of those with the tumour without associated cirrhosis. The possible role of the hepatitis B verus in the aetiology of PHC is considered in the light both of these findings and of the possibility that the frequency with which the tumour is associated with cirrhosis may be decreasing in Shangaans. Some of the dietary habits of the Shangaans with PHC were compared with those of the controls. Virtually all the patients with PHC, but also almost all the controls, ate groundnuts in large quantities from an early age, as well as cashew nuts in smaller amounts. Cycad pips, mopani leaves and pods, mopani worms and locusts were not eaten by significantly more of the Shangaans with PHC than the controls. The limitations of this type of dietary analysis are discussed.
| 66,757
|
Further evidence for the involvement of base and base sequence in the antigenic determination of thermally denatured DNA.
|
The antigenic determinant of thermally denatured salmon sperm (ss) DNA was extensively investigated with a radioimmunoassay technique using the ssDNA immune system. It was demonstrated that mixed sequences of purines and pyrimidines play a key role in the antigenic determination of DNA. On the other hand, the importance of the bases in the manifestation of DNA antigenicity was demonstrated by using brominated, methylated and/or ultraviolet irradiated ssDNA preparations.
| 66,773
|
Duplication of the haemoglobin alpha-gene.
|
Gene duplication is one of the basic processes underlying evolutionary changes. The gamma-chains of human foetal haemoglobin is coded by multiple structural genes. The delta-chains of Hb A2 can be regarded as a duplication of the beta-locus. We have presented the first evidence for the presence of two major alpha-chain loci in man. The alpha-gene appears to have duplicated recently, since apart of the single point mutations characterizing Hb J-Buda and Hb G-Pest, the two alpha-gene products seem to be identical. Sensitive immunochemical measurement techniques may reveal structural differences which might escape detection by chemical methods based on differences in charge and/or chromatographic behaviour. Anti-alpha-chain sera recognizing the single amino acid substitution in alphaJ-Buda could be raised in rabbits. The anti-alpha-chain sera were found to be more powerful tools for detecting differences in the primary structure of the chain than the immune sera raised against the whole tetramer. None of the immune sera could reliably differentiate Hb G-Pest from Hb A1. The relative strength of complement fixation of the alpha-chains from haemoglobin A1 F and A2 was compared by hybridizing these human haemoglobins with caninehaemoglobin and measuring the quantitative complement fixation of the different hybrids with anti-Hb A1 and anti-alphaA1 rabbit immune sera. No antigenic difference among the alpha-chains from haemoglobins A1, A2 and F could be detected by this method either with anti-A1 or with anti-alphaA1 sera. These results do not exclude the possibility of conformational differences between the alpha-chains in native Hb A and Hb F. The antigenic activity of the alpha-chains of Hb A from normal subjects (alphaA1) and of the alpha-chains of Hb A from a double heterozygote for alphaJ-Buda and alphaG-Pest (alphaA1) were compared by the complement fixation technique. Definite differences could be detected in the relative strength of complement fixation by alphaA1 and alphaA1 with anti-alphaA1 serum. Final decision as to whether alpha-chain duplication is a universal phenomenon or whether it is restricted to only a part of mankind cannot be drawn until the presence of a silent alpha-thalassaemia gene is not excluded in some debated cases by reliable chemical methods. Measurement of alpha-globin genes in Hb H disease with cDNA enriched in alpha-globin sequences provided direct evidence that a non-thalassaemic subject has to have at least four alpha-globin genes per diploid cell.
| 66,838
|
Atypical stromal hyperplasia of the prostate gland.
|
Hyperplastic lesions of the prostatic stroma with atypical changes are presented and discussed. One lesion was a leiomyoma with atypical organization and a limited area of nuclear pleomorphism without mitotic figures. One was a lesion which in many portions was histologically indistinguishable from leiomyosarcoma. It, however, had certain features probably connoting less sinister behavior, and at autopsy 16 months after resection there was no evidence of recurrence or metastasis. One lesion histologically resembled fibroadenoma of the female breast. These three lesions occurred in patients more than 50 years who had symptoms and signs of prostatism. Reference is made to two previously reported lesions reminiscent of cystosarcoma phyllodes of the female breast. All the lesions were located in the craniad prostate, which is estrogen-influenced. A parallel is drawn between these atypical changes in prostatic fibromuscular stroma and atypical changes in the connective tissue stroma of the female breast.
| 66,868
|
[Triggering of human peripheral blood B cells by supernatants of activated T cells: the role of Ia-like determinants].
|
Human peripheral blood B lymphocytes, isolated by Sephadex G-200 anti-Fab column chromatography, were non specifically induced by either pokeweed mitogen (PWM) or soluble products of antigen stimulated T cells, to differenciate into plaque directed against human Ia-like antigens (anti-p 23-30) inhibited the differenciation of B cells into antibody forming cells. Thus, while PWM induced proliferation was only mildly reduced by anti-p 23-30, the PWM induced PFC response was totally abrogated. Conversely, the antiserum abolished both the proliferative and the PFC responses generated by products of activated T cells. Using both Ouchterlony plates and co-precipitation techniques, we were unable to detect p 23-30 molecules on the active products present in the T cells supernatants. These data suggest that the inhibitory effects are secondary to interaction of the antiserum with B cells determinants.
| 66,895
|
Experimentally induced bleomycin sulfate pulmonary toxicity: histopathologic and ultrastructural study in the pheasant.
|
Morphological alterations in the lungs of pheasants after prolonged high-dosage administration of bleomycin sulfate were studied by light and electron microscopy. Nontreated birds acted as controls, and their lungs showed no abnormalities. Lungs of bleomycin-treated pheasants revealed collapse alternating with overexpansion, marked cuboidalization of atrial epithelium, and incipient interstitial fibrosis. There were neither lymphoplasmacytic or eosinophilic infiltrates, nor evidence of vasculitis. Ultrastructurally, type 1 alveolar epithelial cells were either reactive or conspicuously absent in the air capillaries. Type 2 alveolar epithelial cells appeared hyperplastic with numerous lamellar bodies, many of which extruded into air spaces. Immature fibroblasts were noted in the vicinity of collagen fibrils or amorphous material resembling elastin. No immune deposits were present in basement membranes. These findings are consistent with a direct toxic effect of bleomycin to the pheasant lung rather than a drug hypersensitivity reaction. Reproduction of the bleomycin lesion in a nonmammalian species corroborates even further the high propensity of the drug to affect the lung.
| 66,910
|
Alpha-foetoprotein and carcinoembryonic antigen in germ cell neoplasms.
|
Serum alpha-foetoprotein (AFP) and serum carcinoembryonic antigen (CEA) levels were measured, serially whenever possible, in 70 patients attending the Institute of Radiotherapy, Rotterdam, on account of testicular (65) or ovarian (4) germ cell tumours or, in one case, an endodermal sinus (yolk sac) tumour in the mediastinum. In 15 patients the disease was active; in the others it was in remission. Patients with active disease had raised serum AFP levels which correlated well with disease activity; no patient without evidence of active disease had raised serum AFP levels. None of the patients with active disease was found to have raised serum CEA levels. There was no correlation between serum AFP and CEA levels in patients with germ cell neoplasms, but good correlation between serum AFP levels and disease activity. Serum CEA levels did not correlate with disease activity, and serial determinations would therefore not be useful in monitoring progress in this group of diseases.
| 66,925
|
The secondary structure of myelin basic protein extracted by deoxycholate.
|
Because of the implication of myelin basic protein in some neurological diseases its in vivo structure is of particular interest. The protein is usually isolated using organic solvents and acid solutions and has previously been shown to contain little alpha-helical or beta-structure; but it is not known how the extraction methods influence the structure. Following recent observations that deoxycholate generally causes minimal structural perturbation when used to dissolve membrane proteins, this detergent has been used to extract the basic protein from bovine myelin. The protein contained in deoxycholate washes of myelin has been purified by gel chromatography and its secondary structure examined by circular dichroism spectroscopy. This protein and conventionally prepared bovine and human basic protein to which 1% deoxycholate has been added appear to have the same structure: they contain 8-14% more helical structure than the chloroform/methanol-extracted protein in pH 4.8 acetate buffer or in pH 9.15 Tris buffer. This conformational change is unaffected by addition of 0.25 M NaCl. The helical content will approach the upper limit if, as is expected, these ordered segments are short. It is suggested that basic protein may adopt this more ordered structure in myelin and possess activity not apparent in its water-soluble unordered conformation. Retention of its encephalitogenic activity following severe treatment may result from an ability to rapidly refold to the original conformation rather than from this activity being inherent in the unordered form.
| 66,935
|
[In vitro and inhibition of anaphylactic reactions 1-methyl-3-isobutylxanthine].
|
1-methyl-3-isobutylxanthine (MIBX), a potent antiphosphodiesterase drug, inhibited the anaphylactic reactions both in vitro and in vivo: anaphylactic histamine release from the isolated mast cells of rats, anaphylactic contracture of the isolated trachea of guinea pigs, passive cutaneous anaphylaxis (PCA) in mice and anaphylactic bronchial constriction (ABC) in guinea pigs. MIBX inhibited the anaphylactic reaction of the trachea, PCA and ABC more than the corresponding reactions induced by histamine.
| 66,950
|
The effect of cations on C-band formation in human chromosomes.
|
A number of salt solutions were tested for their ability to replace 2 X SSC in the production of C-bands with the so-called CT technique. Those containing monovalent cations, except for the ones with Ag+ ions, were capable of inducing C-bands in Ba(OH)2-pretreated human chromosomes. Cesium cations were the most effective in this respect. In contrast to the effect of the monovalent cations studied, di- or polyvalent cations (and Ag+ cations) were incapable of producing C-bands, but appeared to stabilize the Ba(OH)2-induced reverse-banding pattern, This stabilizing effect was obtainable with relatively low cation concentrations and persisted even when C-band-producing cations were present at the same time. The experiments clearly show that the cations present during salt incubations, generally used in the CT- and several other banding methods, can exert a pronounced influence on chromosome behavior.
| 67,010
|
Pathophysiology of generalized penicillin epilepsy in the cat: the role of cortical and subcortical structures. I. Systemic application of penicillin.
|
The mechanism of precipitation of generalized epileptiform discharges in feline generalized penicillin epilepsy, a model of human generalized corticoreticular ('centrencephalic') epilepsy, was studied in acute and chronic experiments in cats with implanted skull and intracerebral electrodes. Single shock and low frequency repetitive stimulation of subcortical sites from which prior to penicillin administration spindle activity and recruiting responses could be elicited, readily triggered epileptiform discharges in the same animals after penicillin. These structures comprised the intralaminar and midline thalamic nuclei, the neostriatum, and some posterior thalamic association nuclei (Pulvinar and nucleus lateralis posterior). Subcortical and cortical structures which prior to penicillin elicited neither spindle activity nor recruiting responses were significantly less effective in triggering generalized epileptic bursts after penicillin injection. The probability with which such bursts were elicited from these structures was still, however, in many instances above chance level. It is concluded that the generalized epileptiform discharges in feline generalized penicillin epilepsy can be triggered from a large number of brain sites, but most reliably so from subcortical nuclei involved in spindle generation and recruiting responses. The experimental evidence presented still does not allow one to determine whether epileptic alteration of neuronal function in this form of epilepsy primarily resides in cortical or subcortical nerve cells or in both.
| 67,024
|
General-purpose timer from transistor logic to auxiliary equipment.
|
This paper describes a low-cost circuit for the control and timing of auxiliary experimental equipment by a variety of signals from 5 V, integrated-circuit logic. The circuit is designed for variable timing and switching up to 240 AC V at 3 A, with two independent timing parameters, delay and duration, in response to positive-going or to negative-going logic signal transitions.
| 67,033
|
Comparison of diagnostic accuracy of different peripheric parameters of thyroid function.
|
Diagnostic value of a scope of peripheric parameters of thyroid function was assessed in an unselected group of untreated patients with suspected thyroid disorder, further in untraeted selected patients (without cardiac involvement) and in treated patients. Comparison of relative values of individual tests was performed, based on relation to plasma thyroid hormone level represented by PBI. It was found that: 1. The diagnostic value of heart rate, plasma cholesterol level, B. M. R. and Hegglin's sign (T-2s interval) is of a very limited degree. 2. The diagnostic accuracy of AJT, Q-Kd interval and PEP was found to be of considerable interest even in unselected patients. Values of IRVD and D indices found for these tests are comparable and allow the immediate estimation of thyroid function in bedside diagnosis. 3. The diagnostic value of PEP could be enhanced by exclusion of patients with suspected or proved cardiac disorder or myocardial failure; this may be useful for physiologic studies. 4. While heart rate is profoundly and inconsistently influenced by beta-blockade, AJT is influenced to a minimal degree only and Q-Kd and PEP are uniformly shifted to higher values, allowing thus diagnostic evaluation during this form of treatment also. 5. As Q-Kd is considerably age-and height-dependent, AJT and PEP are believed to be the most suitable test for immediated clinical diagnosis.
| 67,035
|
Multiple sclerosis: a clinico-biological study of 100 cases in Spain.
|
A study was carried out on 100 cases with the clinical diagnosis of multiple sclerosis. Several clinical and analytical factors were considered and correlated. Special attention was paid to data obtained from cerebrospinal fluid (CSF) electrophoresis. The degree of severity of the disease does not affect the selective evaluation frequency of gamma-globulin or its average values. A greater frequency of definite gamma-globulin increase is observed in patients with a stationary development than in those a progressive development although, in both instances, the average values of gamma-globulin do not show any significant difference. There is no correlation between the CSF data and the presumed clinical site of the lesion. Those patients with a single lesion have a lower incidence of pathological data in CSF than those with multiple lesions. A higher proportion of pathological results is seen in CSF of patients with a chronic evolution from the onset than in chronic-intermittent cases. The cases studied during a relapse show a marked decrease in the frequency of definite gamma-globulin increase and paretic colloidal curves. This group of patients gives lower average values of gamma-globulin, total protein and cells, than those patients examined out of relapse. These results are in agreement with recent immunopathological observations.
| 67,039
|
Fluorescent C bands of human chromosomes with 33 258 Hoechst stain.
|
Air-dried preparations of human metaphase chromosomes normally exhibit a Q band fluorescence pattern with 33 258 Hoechst stain while the C band regions of 1,9,16, and most acrocentric short arms appear dull. If these stained and mounted slides are stored at room temperature in the dark for several days, a spontaneous change from C-negative to C-positive band some times occurs. We postulate that the pH of the buffered saline mounting medium during storage of the slides causes the C band shift since the results can be duplicated experimentally by lowering the pH of the mounting buffer from 5.5 to 4.0.
| 67,076
|
Immunological properties of ampicillin polymers.
|
The immunologic effects of ampicillin polymers were studied in mice and rabbits. Polymerized ampicillin--in contrast to monomers--had a suppressive effect on the antibody response to penicilloylated proteins. Unfractionated ampicillin polymer, and high molecular weight fractions were found to have an immunogenic effect in mice, when tested by a haemolytic plaque assay. The immunogenic effect of variously sized polymers did not correspond to their antigenic activity as reflected by passive cutaneous anaphylaxis experiments.
| 67,086
|
Failure of increased intracranial pressure to affect rapid axonal transport at the optic nerve head.
|
In owl monkeys, elevation of intracranial pressure to 500 mm. saline for 4 to 7 hours failed to cause an accumulation at the optic nerve head of protein carried by rapid axonal transport. This suggests that the block of rapid transport observed by others during papilledema may be the result of axon swelling, not its cause. Alternatively, more than 8 hours may be required for intracranial pressure to show an effect, only the slow transport may be affected initially, or other factors than simple hydrostatic pressure may be operative in papilledema. In addition, the elevated intracranial pressure did not prevent the block of axonal transport at the lamina cribrosa produced by elevated intraocular pressure, even though the elevated intracranial pressure reduced the pressure gradient to which the axon is subjected as it crosses the lamina cribrosa. Perhaps the block produced by intraocular pressure is not due to a simple mechanical or hydrostatic mechanism.
| 67,095
|
Bladder wall tension in benign prostatic hypertrophy.
|
Two hundred forty-three synchronous urinary flow and intravesical pressure recordings were carried out on 51 men all of whom were over 50 years of age. They consisted of 12 normal subjects and 39 patients with benign prostatic hypertrophy in various stages of bladder outlet obstruction. Bladder wall tension was determined from each pressure and flow recording. Bladder wall tension at the commencement of micturition was found to be of value for the diagnosis of bladder outlet obstruction attributable to benign prostatic hypertrophy. A technique for direct recording of bladder wall tension is desirable.
| 67,098
|
Specificity of the Tumor-specific transplantation antigen induced by JC virus, a human polyomavirus.
|
The specificity of the tumor-specific transplantation antigen (TSTA) induced by JC virus was investigated by cross protection tests in weanling hamsters. Hamsters immunized with JC virus, BK virus, or SV40 were challenged 5 weeks later with known numbers of JC virus- or SV40-induced hamster tumor cells. Both the JC virus-immune and the SV40-immune hamsters showed resistance to challenge with homologous but not heterologous tumor cells, and the BK virus-immune hamsters were not resistant to either heterologous tumor cell. The TSTA induced by JC virus did not cross-react with that induced by SV40.
| 67,106
|
Microfluorometric analysis of cellular DNA following incorporation of bromodeoxyuridine.
|
Bromodeoxyuridine (BrdU) incorporation into cellular DNA has a differential effect on the cell-associated fluorescence of several DNA-specific dyes. After cells were treated with BrdU, flow microfluorometry was used to study the relative increase or decrease influorescence of stained cells. Bromodeoxyuridine incorporation into CHO cells increased the fluorescence of mithramycin-, olivomycin-, or chromomycin-stained cells, decreased that of propidium iodide-stained cells, and had little, if any, effect on the fluorescence of acriflavine Feulgen-stained cells. Changes in relative fluorescence of cell associated dyes are due to changes in the amounts of dye bound to cells with BrdU-substituted DNA. Colorimetric and absorbance measurement of DNA content showed that BrdU does not alter the diploid DNA content of CHO cells; however, BrdU induces perturbations in the distribution of cells about the cell cycle which cause an increase in average DNA content.
| 67,119
|
A comparison of the analgesic effect of oxymorphone by rectal suppository and intramuscular injection in patients with postoperative pain.
|
The relative analgesic potency of oxymorphone by rectal suppository and intramuscular injection was evaluated in a double-blind, twin-crossover comparison of graded single doses in 136 patients with postoperative pain. The time-effect curves of the two routes of administration differed substantially; rectal resulted in lower and more delayed peak analgesia and a longer duration of action than intramuscular administration. When both duration and intensity of analgesia are considered (total effect), rectal oxymorphone was 1/10 as potent as the intramuscular form; in peak effect, it was only 1/16 to 1/20 as potent. However, because intramuscular oxymorphone is nine to ten times as potent as intramuscular morphine, 5 to 10 mg oxymorphone by suppository provides analgesia comparable to that provided by the usually used doses of parenteral narcotics. Rectal oxymorphone produced no more, and perhaps somewhat fewer, side effects than doses of intramuscular oxymorphone producing equivalent total analgesic effect. None of the patients objected to the rectal route of analgesic administration. This study demonstrates the feasibility of well-controlled analgesic assays employing the double-dummy technique to compare suppositoreis with oral or parenteral analgesic dosage forms. Our observations also suggest that the rectal route is an acceptable and practical way of administering potent analgesics and is probably being underutilized by physicians in the control of moderate to severe pain.
| 67,128
|
Experimental infection with Ancylostoma caninum larvae in mice. IV. Serum protein pattern during primary infection.
|
Serum protein of Swiss albino mice infected with Ancylostoma caninum larvae, were analysed electrophoretically. Twenty mice were infected with a dose of 1000 larvae and the alterations in serum protein during an infection period of 30 days were recorded and compared with uninfected controls. The result showed a significant decrease in albumin and gamma globulin with an increase in beta globulin. There were no significant changes in the alpha-1 and alpha-2 globulins. The total globulins increased and A/G ratio decreased. These changes appeared to be remarkable on the 9th day after infection.
| 67,139
|
Murine plasma cells secreting more than one class of immunoglobulin heavy chain. II. SAMM 368--a plasmacytoma secreting IgG2b-kappa and IgA-kappa immunoglobulins which do not share idiotypic determinants.
|
SAMM 368 is a BALB/c plasmacytoma which secretes IgG2b-kappa and IgA-kappa paraproteins. Immunofluorescence studies of ascites cells from the tumor with purified, heavy chain class-specific antiglobulins demonstrate that single cells contain both IgG2 and IgA heavy chains. Idiotypic antisera prepared in mice and rabbits indicate that the two paraproteins produced by the tumor do not share idiotypic determinants. Analysis of the purified paraproteins for allotype markers showed that SAMM 368 IgA bears the BALB/c A12,13,14 determinants. SAMM 368 IgG2b does not carry any detectable allotypic determinants in spite of the fact that heterologous antisera identify the paraprotein as IgG2b.
| 67,144
|
Studies on H-2 specificities on mouse tumour cells by a new microradioassay.
|
Seven mouse tumour cell lines of different aetiology and origin were tested for the expression of surface alloantigens using twenty-four well defined H-2 alloantisera and anti-Thy 1.2. We used a new radioassay that involves antibody-complement treatment of the tumour target cells followed by postlabeling the surviving tumour cells with 14C-thymidine. With a relatively high frequency the anti-H-2 sera were reacting differently with the tumour cells than with respective syngeneic lymphoid cells. Thirty-six anomalous reactions out of 129 investigated were detected. Absorbtion experiments performed with H-2 antigen positive or negative lymphoid cells revealed a striking similarity between these extra-specificities and H-2 specificities of foreign haplotypes. The results are discussed in relation to the biological importance of the extra-specificities, both with regard to origin (derepression) and function (transplantation antigen properties).
| 67,153
|
Effect of combinations of penicillin and aminoglycosides on Streptococcus faecalis: a comparative study of seven aminoglycoside antibiotics.
|
The 50% inhibitory concentrations (IC50) of benzylpenicillin, streptomycin, sisomicin, gentamicin, tobramycin, kanamycin, amikacin, and butirosin were determined for 58 clinical isolates of Streptococcus faecalis, 28 of which were recovered from cultures of blood samples from patients with endocarditis. The IC50 of streptomycin was less than 100 microng/ml for 42 strains, 192-10,000 microng/ml for eight, and larger than or equal to 10,000 micron/ml for eight. One isolate that was highly resistant to streptomycin was also highly resistant to kanamycin and butirosin. Extraordinarily high resistance to the other aminoglycosides was not observed. The bactericidal effects of combinations of penicillin and aminoglycosides were studied in 20 strains of S. faecalis that represented different levels of resistance to streptomycin. Significant enhancement of the effect of the combination of penicillin and streptomycin was found only in strains with an IC50 of smaller than or equal to 190 microng/ml. Combinations of penicillin and sisomicin, gentamicin, or tobramycin were effective even against strains that were highly resistant to streptomycin and kanamycin.
| 67,159
|
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