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HLA-DW3 associated with coeliac disease.
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28 patients with coeliac disease (C.D.) were typed for the HLA-A, -B, and -D loci by several techniques. It was found that C.D. is primarily associated with the DW3 determinant and only secondarily with HLA-B8. The previously described association with HLA-B8 is explained by linkage disequilibrium between HLA-B8 and DW3.
| 55,781
|
Enhanced preservation of the ischaemic kidney with inosine.
|
The function of rat kidneys subjected to 60 minutes of warm ischaemia at body-temperature was notably protected by the prior administration of the purine nucleoside inosine as a 40 mg/ml solution maintained at 37 degrees C. With direct intrarenal arterial perfusion of the kidney at the onset of ischaemia or with intraperitoneal (i.p.) injection 40 minutes before ischaemia, the plasma-creatinine at 24 hours was significantly lower (P less than 0-001) than that of untreated 60-minute-ischaemia controls and not significantly different from that of non-ischaemic unilateral-nephrectomy controls. Intravenous inosine 20 minutes beforehand also afforded significant (P less than 0-01) protection. 7-day survival was 100% in 30 inosine-pretreated rats and 65% in 45 rats with all other types of pre-treatment (P less than 0-001). Although i.p. adenosine was better (P less than 0-05) than no treatment, i.p. inosine was better (P less than 0-02) than i.p. adenosine. Allopurinol, phenoxybenzamine, A.T.P., or cyclic A.M.P. caused no improvement over controls. Kidneys perfused with inosine maintained higher purine-nucleotide levels during ischaemia and rapidly resynthesised A.T.P. when blood-flow was restored in vivo.
| 55,837
|
The chemical nature of human atrial specific granules.
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The nature of human auricular specific granules was assessed by a variety of cytochemical and histochemical methods. The specific granules were found to be argentaphobic when ultrathin sections of Araldite-embedded auricular appendages were stained according to the periodic acid-thiocarbohydrazide-silver proteinate technique of Thiery. The entire core of these granules was moderately positive after ultrathin sections of glutaraldehyde-fixed, glycol methacrylate (GMA)-embedded auricles were stained with phosphotungstic acid (PTA) at a low pH. A similar reaction was shown by the cell coat, residual bodies (C-granules), lysosomes, Z-discs as well as by a very small portion of the Golgi complex. Analogous results were obtained in semithin sections of GMA-embedded auricles stained by the periodic acid-Schiff (PAS) technique. Incubation of ultrathin sections (fixed in glutaraldehyde and embedded in GMA) with proteolytic enzymes (pronase, pepsin, trypsin, or alpha-chymotrypsin) elicited selective digestion of atrial specific granules and Z-bands and, to a much lesser degree, of the cell coat. It is concluded that human auricular specific granules, as in rat atrial cardiocytes, are composed mostly of proteins. In addition, these granules may contain complex carbohydrates.
| 56,022
|
[Influence of nutrition on hormone secretion. I. Study in Agua Preta (author's transl)].
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A positive correlation between the circulating growth hormone levels and the nutritional status was reported in 9 children of both sexes, aged 1 to 6 years, suffering from 2nd degree malnutrition. The mean serum insulin levels, the mean urinary 17-KS and 17-OHCS levels were low before the dietary therapy. No significant correlation between the levels of these hormones and the nutritional status was found. The hormone levels gradually returned to normal after the dietary therapy and the nutritional status of the children improved, according to the observed biochemical, clinical and anthropometric data.
| 56,017
|
Induction of histamine release and desensitization in human leukocytes.
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Histamine release from normal human leukocytes can be induced by anti-IgE or protein A from Staphylococcus aureus. After incubation in buffer at 37 degrees C for various time intervals or repeated washings with buffer, or both procedures, the leukocytes lose most of their reactivity to protein A, whereas the reactivity to anti-IgE is unaltered. Cells deprived of their protein A reactivity can be induced to release histamine by IgG complexed with protein A. Maximal release (23%-81%) from 0.6-1.0 times 10(7) leukocytes per ml is obtained if the mixture contains 1-2 mug protein A and 8-16 mug IgG per ml. The ratio between protein A and IgG in the most active mixtures is 1:8 or 1:16 on a weight basis, which corresponds to 2-4 IgG molecules per protein A molecule. Heat treatment does not destroy the capacity of IgG to mediate histamine release. Mixtures of protein A and the Fc part of IgG can also initiate the release. Futhermore, it is shown that the protein A-IgG mixture and anti-IgE induce cross-desensitization to each other. This indicates that, like cell-bound IgG, IgG in complex with protein A triggers partially the same reaction sequence as IgE.
| 56,030
|
[Lupus syndrome during treatment with isoniazid].
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In a young girl, aged 17 years, there occurred, 9 months after starting treatment with isoniazid and rifampicin, clinical signs of rheumatoid arthritis with facial erythema of vespertilio type. The presence of L.E. cells and antinuclear antibodies with a high titer, the rapid disappearance of all the clinical signs on stopping isoniazid, and the transient exacerbation of the syndrome on giving a single dose of isoniazid, gave the diagnosis of systemic lupus erythematosus induced by isoniazid. 18 months after stopping the drug, the patient is apparently cured, but there persists in the serum antinuclear antibodies in low concentration (1/200). A study of acetylation of isoniazid in this patient and her 3 sisters, showed that they were all of the slow acetylating phenotype. The late prognosis of this disease and the physiopathological value of the slow acetyl phenotype are worth discussion.
| 56,040
|
HL-A8 and LD-8a in patients with myasthenia gravis.
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The frequency of HL-A8 in myasthenia gravis is markedly increased in women (60-80%) but not in men. The MLC determinant, LD-8a, is frequently associated with HL-A8. Of the 37 female MS patients, 15 were LD-8a positive (41%), whereas of the males only one of seven was LD-8a positive. The frequency of HL-A8 was 68% in women and 29% in men with the disease. We therefore conclude that the gene which is responsible for the increased susceptibility to myasthenia gravis in women and which is present in the MHS region, is more closely linked to the SD-2 than to the LD-1 locus.
| 56,059
|
[The effect of drugs on "sino-atrial conduction time" and on sinus-node automaticity in man].
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The effect of atropine, propafenone, and disopyramide on sinus node automaticity and "sino-atrial conduction" was tested in normal patients and patients with the sick sinus-syndrome. "Sino-atrial conduction time" was estimated indirectly by the extrastimulus technique. Atropine (n = 11) caused a significant increase in heart rate in all patients. The sinus node recovery time was shortened in 10 patients. "Sino-atrial conduction time" decreased on an average 35% (P less than 0.01). Three patients with a sick sinus-syndrome demonstrated a change of the pattern of the postextrasystolic pauses indicating great improvement in sino-atrial conduction. Propafenone (n = 10) led to a significant prolongation of the sinus node recovery time by 17% and of the "sino-atrial conduction time" by 27%. Disopyramide (n = 8) had no significant influence on heart rate and "sino-atrial conduction time". Sinus node recovery time was not changed in 6 patients. However, in two patients with a sick sinus-syndrome a dangerous prolongation of the sinus node recovery time after application of disopyramide occurred. The results indicate that atropine enhances sinus node function and sino-atrial conduction. On the other hand, propafenone and disopyramide exert either a depressant influence on sinus node automaticity or on sino-atrial conduction.
| 56,094
|
[The influence of brain dysfunction on child development].
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In childhood and adolescence two forms of so-called ''psychoorganic syndrome" are distinguished. The early form, in the English and American literature called minimal brain dysfunction, impairs the entire development of the personality in its somatic and psychic aspects. It requires extensive therapeutic efforts. Early diagnosis therefore is of great preventive importance. The infantile psychoorganic syndrome which is acquired later in childhood can be distinguished from the early form by the fact that the impairment is usually only temporary, the etiology is understood and therefore understanding for the child is present. Minimal brain dysfunction when it continues into adolescence is called juvenile psychoorganic syndrome. The emotional liability and irritability which characterises the pubescent period are intensified in the early adolescent with juvenile psychoorganic syndrome and therefore stand out. The brain damage acquired in adolescence resembles the one acquired in adulthood. It is characterised however by the problems of this age group (identity, vocational decisions, social sexual maturations etc).
| 56,104
|
Reversible inhibition of rapid axonal transport in vivo by lidocaine hydrochloride.
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Rats were given standardized injections of 3H-L-proline into the trigeminal ganglion and 14C-lidocaine hydrochloride at the infraorbital foramen. The 3H-L-proline was always injected 2.5 h before removal of the nerve. Lidocaine, 1, 2, and 4%, produced a concentration-related inhibition of entry of 3H-labeled rapid axonal transport into the distal portions of the nerve. Addition of epinephrine, 1:200,000, doubled the intensity of the effect. The time delay of recovery was also concentration-related, and with 4% lidocaine recovery still seemed incomplete after 4.5. h. It is concluded that inhibition of rapid axonal transport is probably a usual byproduct of nerve block with local anesthetics such as lidocaine. The inhibition seems attributable in part to a disturbance of the energy metabolism of the nerve.
| 56,150
|
Gene dosage and antigenic expression on the cell surface of bovine erythrocytes.
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Electron microscopic and serological techniques have been used to study the relationship between cell surface expression of bovine erythrocyte antigens and the genes coding for these antigens. Using cells which are genetically and serologically defined for their zygosity with respect to the Z allele, it was found that homozygous (Z/Z) cells have approximately twice as much surface Z antigen as heterozygous (Z/-) cells. Cells labeled for the J antigen, a soluble serum substance which secondarily adsorbs to the erythrocyte surface, display a quantity of antigen which is directly related to the J titer of the cells. A new antigen is described which is independent of the J antigen, and which is detectable by EM labeling and by indirect agglutination, but not by hemolysis.
| 56,151
|
A trial of utilizing antibodies as carriers of alkylating agents. I. Influence of cyclophosphamide and chlormethine on antigenic properties of serum proteins.
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Electrophorograms of human and rabbit sera before and after incubation with various concentrations of cyclophosphamide and chlormethine (Nitrogranulogen) were compared. Sera of rabbits injected with chlormethine and cyclophosphamide in therapeutic doses for humans were examined for antibodies reacting with homologous and antologous gamma-globulins. Immunoelectrophorograms of sera incubated with both alkylating agents differed from those of preincubation sera with regard to number and intensity of precipitin lines. The changes in electrophorograms were related to the type and concentration of alkylating agent. No antibodies to homologous or autologous serum antigens of rabbits treated with chlormethine or cyclophosphamide were found.
| 56,161
|
Antigenic determinants of hen egg-white lysozyme in delayed hypersensitivity. II. Antigenicity and immunogenicity of the N- and C-terminal peptide.
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Various small fragments of (see article) which is one of the immunodominant groups of hen egg-white lysozyme (HL), were tested for macrophage migration inhibition (MMI) of peritoneal exudate cells (PEC) from guinea pigs immunized with HL. P17 was split in the middle with cyanogen bromide. The terminal portion of (see article) showed positive MMI, whereas the non-terminal half of P17, P17i (sequence 13-27) only showed very weak MMI activity. A fragment derived from the middle portion of P17, P17m (sequence 11-22), was inactive. When P17 were reduced and alkylated, one of the resultant peptides, P17N (sequence 1-[CM-Cys-6]-27) still has MMI activity with PEC taken from guinea pigs immunized with HL, although no antibody reacting with it was detected, but P17C (sequence 123-[CM-Cys-127]-129) was inactive. The peptides P17 and P17N were both immunogenic in guinea pigs in respect to the delayed hypersensitivity response. Again P17t and P17N were immunodominant groups, but the reactivity of P17i in MMI assay of this group of animals was greater than that in guinea pigs immunized with HL. The reactivities of HL with PEC taken from guinea pigs immunized with P17 or P17N were generally weaker than those of the antigens used for immunization.
| 56,172
|
Rabbit collagenase. Immunological identity of the enzymes released from cells and tissues in normal and pathological conditions.
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1. The immunological cross-reactivity between rabbit collagenases from a variety of normal and pathological sources was examined. The specific antibody raised against collagenase secreted from normal rabbit synovial fibroblasts gave reactions of complete identity with collagenases secreted from fibroblasts derived from rabbit skin, and from synovium from experimentally arthritic rabbits. 2. The rabbit fibroblast collagenase was immunologically identical with collagenases obtained from the organ culture medium of normal rabbit skin, synovium, ear fibrocartilage and subchondral bone. 3. Collagenases from the culture media of normal rabbit synovium and from hyperplastic synovium of rabbits made experimentally arthritic were identical. 4. The collagenase secreted from rabbit fibroblasts gave a reaction completely identical with that of a collagenase extracted directly from a rabbit carcinoma. 5. IgG (immunoglobulin G) from a specific antiserum to rabbit fibroblast collagenase was a potent inhibitor of the collagenases obtained from the culture media of the various rabbit cells and tissues. 6. Collagenases from human synovium and from mouse macrophages and bone were neither precipitated nor inhibited by antibodies to rabbit collagenase. 7. No immunoreactive material was found in lysates of rabbit polymorphonuclear leucocyte granules with the specific antisera to rabbit fibroblast collagenase. No evidence for inactive forms of rabbit collagenase in lysates of the rabbit synovial fibroblasts could be found, either by double immunodiffusion against the specific collagenase, or by displacement of active enzyme from inhibition by the IgG.
| 56,176
|
Histamine release in human subjects by modified gelatin (Haemaccel) and dextran: an explanation for anaphylactoid reactions observed under clinical conditions?
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Histamine release by modified gelatin (Haemaccel) and dextran (Macrodex) has been demonstrated in volunteers by direct and indirect methods. In a pilot study of Haemaccel, histamine release was observed in six of seven volunteers. The highest plasma histamine concentration was 4.8 ng/ml, the lowest 1.7 ng/ml: two of the subjects showed slight allergic reactions. Using Haemaccel batch 2551, 10 out of 12 subjects reacted to the rapid infusion of Haemaccel with increased plasma histamine concentrations, whereas none reacted to Ringer's solution. None of the 10 subjects had an allergic reaction, but an increase in gastric secretion was observed in eight. Changes in the venous basophil granulocyte count were found in both those who reacted and those who did not react to Haemaccel. After the rapid infusion of dextran the highest plasma histamine concentration was 5.0 ng/ml, the lowest 1.3 ng/ml. The withdrawal of blood had no influence on plasma histamine concentration. The incidences of histamine release produced by Haemaccel varied with different batches. Thus, it seems unlikely that immunological mechanisms are principally responsible. Nine instances of allergic and anaphylactoid reactions to plasma substitutes have been reported, seven after Haemaccel infusion, and two after dextran administration. One of the patients who received dextran died. Histamine release was always associated with Haemaccel infusion and corresponded in extent to the clinical symptoms observed, but there was no significant histamine release associated with the reactions to dextran.
| 56,183
|
Production of beta-(4-hydroxyphenyl)ethanol and beta-(4-hydroxyphenyl)lactic acid by Candida species.
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Two crystalline compounds were isolated from the culture filtrates of Candida species grown in synthetic medium supplemented with L-tyrosine as the sole source of nitrogen. These compounds were characterized as beta-(4-hydroxyphenyl)ethanol (HOPEA) and beta-(4-hydroxyphenyl)lactic acid (HOPLA). The production of these compounds in five species (both pathogenic and non-pathogenic) was compared and marked differences were revealed. Experiments using L-[14C]tyrosine indicated that both HOPEA and HOPLA are synthesized from L-tyrosine.
| 56,213
|
Human nucleolar organizer chromosomes: satellite associations.
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The D and G group chromosomes from cultured human lymphocytes exhibit single and multiple satellite associations when stained with silver. Unlike earlier methods this simple and highly repeatable procedure shows physical attachments between satellited regions of various acrocentric autosomes. After studying 1,000 satellite associations from 118 normal individuals, it was found that both single and multiple associations occur with frequencies that correlate with random expectancies.
| 56,257
|
[EEG effects of sodium nitroprusside and hemodynamic references].
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A study was performed on baboons (Papio papio) of various hemodynamic and EEG effects of sodium nitroprussiate (SNP), substance with powerful vasodilator action. Three different procedures of drug injection were used: (1) in isolation, either in doses close to those used in clinical practice or in high doses; (2) after neuroleptanalgesia (NLA); (3) after causing vasospasm. With isolated SNP, effects on blood pressure were unstable; in certain cases hypotension could be maintained only with toxic doses. Hypotension was facilitated when NLA had been previously induced. At low doses the cerebral blood flow (CBF) was practically unmodified, whereas at toxic doses it first increased then decreased. In animals under NLA, the CBF drop was only moderate, suggesting persistence of adequate spasm, CBF was significantly improved through SNP. The EEG did not undergo sizeable change at low SNP doses given in isolation; toxic doses always induced alterations with peculiar morphology, but developing only tardily after SNP perfusion was begun. This lag may indicate that hypotensive and toxic SNP effects are dissociated. These alterations suggest that screening of the EEG is necessary during prolonged administration of SNP, e.g., in surgical procedures. Combining NLA and SNP (at low doses) causes EEG deceleration, but no great alteration of the rhythms, as observed during other types of controlled experimental hypotension. Hence, cerebral circulation may be relatively well protected during SNP hypotension.
| 56,263
|
Visual evoked response in senile and presenile dementia.
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The visual cortical evoked response was studied in 19 patients suffering from a condition diagnosed as senile or presenile (type Alzheimer) dementia. When compared with a group of normal subjects used as reference group, the latencies of waves II through VI were increased or markedly increased in these patients, and the amplitudes of waves III and VI (and, less consistently, those of waves II and IV) were increased. This corroborates the sparse data on other types of dementia available in the literature.
| 56,264
|
Postnatal development of human brainstem potentials during the first year of life.
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Average brainstem potentials evoked by auditory stimuli were recorded from the scalp's surface of human newborns and infants, 6 weeks, 3 months, 6 months and 1 year of age as well as from normal adults. The auditory processes related to peripheral transmission (PT) and central transmission (CT) were shown to mature at differential rates during the first year of life. By the 6th week PT had reached the adult latency. In contrast, CT through the brainstem did not match that of the adult until approximately 1 year of age. In addition, the waveform of the brainstem evoked potential (BEP) displayed an independent time course for development. The adult configuration replaced the infantile response by 3--6 months. Despite considerable inter-subject variability in the BEP amplitude during the neonatal period, a general wave-form pattern could easily be delineated. Preliminary results revealed the BEP to be quite resistant to habituation following continuous stimulus presentation. Longitudinal follow-ups on several babies paralleled the transverse data.
| 56,268
|
Specific immunological test for the rapid identification of members of the genus Histoplasma.
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A sensitive and specific immunological method was developed for rapid identification of the mycelial forms of Histoplasma capsulatum var. capsulatum, H. capsulatum var. duboisii, and H. farciminosum and for separation of these pathogenic fungi from morphologically similar hyphomycetes and other fungal pathogens. This method is based on the fact that all of the Histoplasma spp. produce H and M histoplasmin antigens, whereas the other fungi do not. Inocula consisting of heavy mycelial growth from a pure, full-grown culture were transferred into flasks containing small volumes of brain heart infusion broth. These cultures were placed on a shaker and grown at 25 C. Using the micro-immunodiffusion technique and antisera containing antibodies to H and M precipitinogens, we detected exoantigens in 3-day-old brain heart infusion culture supernatants concentrated 25 and 50 times. The ability of the procedure to identify Histoplasma spp. was evaluated by testing 96 unknown mycelial cultures that grossly or microscopically resembled Histoplasma spp. Three- and six-day-old concentrated culture supernatants prepared from each unknown were tested against rabbit anti-Arthroderma tuberculatum, Chrysosporium keratinophilum, H. capsulatum var. duboisii, and Corynascus (Thielavia) sepedonium sera and human histoplasmosis case serum. Each unknown was also identified by conventional laboratory procedures involving cultural and, where necessary, in vivo studies. In the comparative evaluation the immunological test was observed to be 100% sensitive. It permitted the accurate generic identification of the Histoplasma spp. within 5 days, in contrast to the average of 33 days required by the routine mycological procedure.
| 56,339
|
Quantitative fluorescence spectrophotometry of acridine orange-stained unfixed cells. Potential for automated detection of human uterine cancer.
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After staining with acridine orange (AO), the nuclei of unfixed cells from the human female genital tract exhibited the same fluorescence behavior previously observed for human and murine leukocytes and mouse ascites tumor cells. With staining conditions chosen to assure saturation of the green-fluorescing AO-nucleic acid complex in normal cells, corrected fluorescence emission spectra were recorded from the entire nucleus of 341 cells taken from 32 normal and 28 abnormal patients. Intensity of the recorded spectra was expressed in phosphor particle units, a fixed arbitrary unit of fluorescence intensity, to display intensity differences among the spectra from the various cell types. In all abnormal samples, one or more cells were found with 530-nm nuclear fluorescence intensity considerably greater than the maximum intensity recorded from normal cells. Determination of the adequacy of 530-nm nuclear fluorescence intensity as a criterion for cancer detection requires additional investigation. Additional criteria, if needed, may be supplied by the metachromasy of AO-stained unfixed cells.
| 56,389
|
Dimethyl sulfoxide-lead tetraacetate method for histochemical oxidation of polysaccharides.
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Oxidation of fixed tissues and unfixed peripheral blood smears by 1% (w/v) lead tetraacetate in dimethyl sulfoxide for 10 to 60 min resulted in facile induction of tissue carbonyls readily demonstrable with Schiff's reagent and by sodium bisulfite addition reaction, followed by toluidine blue staining at controlled pH. Tissue carbonyls represented a broad range of oxidation-labile substrates and included neutral polysaccharides (glycogen). The oxidation procedures were not destructive to tissues and were characterized by technical simplicity and consistent reproducibility, thus affording a substantial improvement over the hitherto used methods of histochemical oxidation by lead tetraacetate.
| 56,394
|
Effect of proteolytic digestion on the structure and function of human properdin.
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Human properdin (P) was found to be sensitive to the action of trypsin, chymotrypsin, pepsin, and Streptomycetes caesipitosus protease. Incubation of P with these enzymes resulted in loss of its functional activity and the production of antigenically deficient components compared to untreated P. Upon incubation with trypin, P was initially cleaved into a minor fragment and a major fragment. Further degradation ot the fragments occurred with prolongation of inculation time. The minor fragment was highly susceptible to further proteolysis compared to the major fragment which contained the carbohydrate moiety of the molecule. SDS-polyacrylamide gel electrophoretic analysis of trypsin-digested P suggested that the subunit polypeptide chains were initially cleaved at similar points to produce the major and minor fragments. The sedimentation velocity of the major fragment was higher than that of the intact molecule. The implications of these observations of the configuration of P are discussed.
| 56,403
|
Gangliosides as markers for murine lymphocyte subpopulations.
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Antibodies to GM1 ganglioside were used to study murine lymphocyte populations. In A, AKR, and BALB/c mice, anti-GM1 reacts with thymocytes and peripheral T cells. This reactivity of anti-GM1, studied by immunofluorescence, is independent of Thy-1 type and appears to be related to the reactivity of cross-reacting antibodies to asialo GM1 and GD1b, rather than GM1 itself. In addition, a subpopulation of lymphocytes reacting with anti-GM1 and anti-immunoglobulin has been found in approximately 26% of the peripheral lymphocytes of C3H mice, nude mice, and nude heterozygotes. This subpopulation is found in small numbers in A, AKR, and BALB/c mice. These studies demonstrate that antibodies to a chemically defined antigen can be used to identify T cells in many strains of mice and may delineate previously unrecognized lymphocyte subpopulations.
| 56,418
|
Idiotypic analysis of lymphocytes in vitro. II. Genetic control of T-helper cell responsiveness to anti-idiotypic antibody.
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When the IgG1 fraction of anti-idiotypic antibodies raised in guinea pigs is injected into mice, sensitization of idiotypic T and B lymphocytes occurs (1-3). In the present study we analyze the genetic requirements for T-helper cell sensitization by anti-idiotypic antibody. This was done by measuring, in a suitable panel of mouse strains, helper cell responsiveness to two anti-idiotypic reagents which recognize distinct, strain-specific idiotypes, namely the A5A and the S117 marker. Whenever helper cell sensitization by anti-idiotypic antibody was successful, helper function could be specifically inhibited by the same and only the same anti-idiotype. This indicates that helper cells induced by anti-idiotypic antibody express idiotypic determinants on their receptors for antigen. Helper cell sensitization by anti-idiotypic antibody was found in all strains expressing the corresponding or a cross-reactive idiotype at the immunoglobulin level. Idiotype-negative strains were always unresponsive to anti-idiotypic stimulation. In addition, responsiveness did not depend on the H-2 haplotype. Since the A5A and the S117 idiotype are markers for V genes in the heavy-chain linkage group, the present results support the view that the same genes in the Ig-1 complex code for variable portions of immunoglobulins and T-helper cell receptors.
| 56,419
|
Educational materials reviewed for AVLINE.
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The need for a central source of information regarding the availability, suitability, and quality of educational materials has led to the development of AVLINE. AVLINE is a computer information service available through the MEDLARS system of the National Library of Medicine. The Association of American Medical Colleges is gathering information from faculty members concerning useful materials and is bringing together content specialists, instructional designers, and technical specialists to review these materials. Information on materials that are recommended is provided to the National Library of Medicine to be cataloged, indexed, and abstracted for ultimate listing in AVLINE. Twenty-eight percent of the material has not been recommended; the many reasons for low ratings are categorized under content quality, instructional design, and technical quality.
| 56,441
|
Comparison of histocompatibility antigens on cultured human tumor cells and fibroblasts by quantitative antibody absorption and sensitivity to cell-mediated cytotoxicity.
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Human tumor and febroblast tissue culture cells were compared to determine the suitability of fibroblasts as control cells in experiments on human tumor serology and cellular immunology. Fibroblasts expressed the same HL-A antigen profile as did melanoma cells. Furthermore, the quantitative expression of the determinants was similar on both cell types. In four of five pairs tested, the fibroblasts displayed similar sensitivity to effector cells generated by mixed lymphocyte culture as did the tumor cells from the same donor, but there were some differences in the effects of specific alloimmune effector cells at high and low effector-to-target ratios on the two types of target cells. Results indicated that fibroblasts are legitimate control target cells for studies in human tumor immunology, if screening assays are done to verify their antigenicity and sensitivity to cell-mediated cytolysis.
| 56,444
|
Dissociation of alpha beta DNA polymerase of avian myeloblastosis virus by dimethyl sulfoxide.
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The alpha beta DNA polymerase of avian myeloblastosis virus was treated with dimethyl sulfoxide to dissociate the enzyme subunits. The dimethyl sulfoxide treated enzymes were passed over phosphocellulose to purify and characterize the dissociated subunits as well as to remove the dimethyl sulfoxide. RNA-directed DNA polymerase, RNase H, and nucleic acid-binding activity were monitored, as well as the subunit structure (on sodium dodecyl sulfate-polyacrylamide gels) of the various enzyme species obtained. With 30% dimethyl sulfoxide, the majority of DNA polymerase and RNase H activities as well as the alpha subunit were displaced from the alpha beta DNA polymerase position on phosphocellulose (0.23 M potassium phosphate) to the alpha DNA polymerase position (0.1 M). The association of DNA polymerase and RNase H activities with the alpha subunit suggests that alpha is the enzymatically active subunit in alpha beta. In addition to alpha DNA polymerase, a minor polymerase species eluted from phosphocellulose at 0.4 M potassium phosphate. The dissociated beta subunit eluted from phosphocellulose at a wide range of salt concentrations (0.28 to 0.5 M potassium phosphate). The dissociated beta subunit bound 3H-labeled murine leukemia virus RNA and [3H]poly(dT)-poly(dA) approximately 20-fold more avidly than alpha DNA polymerase alone. In contrast to the results with the alpha subunit, there was no correlation between DNA polymerase and RNase H activity profiles and the elution profile of the beta subunit from phosphocellulose. These observations suggest the beta subunit is either enzymatically inactive or possesses limited DNA polymerase and RNase H activity when compared with the alpha subunit.
| 56,461
|
Mechanism of interaction of avian myeloblastosis virus reverse transcriptase with avian myeloblastosis virus RNA.
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The synthesis of DNA on avian myeloblastosis virus (AMV) RNA as the primer-template using AMV reverse transcriptase in vitro has been examined as a function of the concentrations of these components, as well as a function of the ionic strenth of the assay medium. The results are consistent with the hypothesis that two types of sites exist on the AMV RNA: inactive "dead-end" sites that merely bind the enzyme, and active binding sites that lead to DNA synthesis. Velocity sedimentation studies of reverse transcriptase reveal that the enzyme becomes a dimer (or oligomer) at low salt concentrations and it is at these concentrations that the two types of sites are evident on the RNA. At high salt concentration the enzyme, which exists primarily as a monomer, is inactive with AMV RNA, although it is active when poly(rA)dT10 is used as the primer-template. We have shown that inactive sites are not due to binding of the reverse transcriptase to nicked regions or to partially denatured RNA molecules. We deduce that inactive sites are those containing incorrect 4S primer molecules. These results are discussed in terms of the mechanism of the interaction of the reverse transcriptase with AMV RNA.
| 56,463
|
Effect of age and cigarette smoking on carcinoembryonic antigen levels.
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Serum carcinoembryonic antigen (CEA) levels were determined by the Hansen-Z-gel technique in 276 healthy volunteers, of whom 154 were smokers and 122 nonsmokers. The mean CEA level was significantly higher in smokers (2.7 ng/ml) than in nonsmokers (1.9 ng/ml) (P less than .001), and a significantly higher percentage of smokers had elevated CEA levels (P less than .05). In both groups, CEA levels were directly related to age. Seventy-six of the 154 smokers who entered the study ceased smoking. Their CEA levels were determined at one, three, and six months after cessation of smoking. Within three months after cessation, elevated CEA levels declined to within the range of nonsmokers and did not appear to be influenced by previous smoking habits. Both age and smoking history must be considered for accurate evaluation of CEA levels. A reappraisal of the diseases associated with elevated CEA levels that considers the influence of age and smoking may invalidate some of the correlations previously reported.
| 56,468
|
Reduction of menstrual blood-loss by prostaglandin-synthetase inhibitors.
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Six patients with menorrhagia due to dysfunctional uterine bleeding and one patient with an intrauterine contraceptive device were treated with prostaglandin-synthetase inhibitors in an attempt to reduce their excessive menstrual blood-loss. Mefenamic acid (six patients) or flufenamic acid (one patient) taken during menstruation for 2-3 cycles reduced menstrual loss in each patient. These preliminary observations suggest a new treatment for a common gynaecological problem and could imply that prostaglandins are involved in the aetiology of excessive menstrual blood-loss in such patients.
| 56,590
|
The activation of antigens of the basement membrane zone by proteolytic enzymes in vitro.
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Following brief exposure of cryostat sections of human skin to the action of proteolytic enzymes (papain or trypsin), there was a pronounced increase in the antibody binding sites of the basement membrane zone, shown in indirect immunofluorescence by an increased intensity in fluorescence of the basement membrane zone as compared with preparations which had not previously undergone incubation, and by an increase of 5-6 (papain) or 4-5 (trypsin) titre dilution steps. This effect was practically absent when guinea-pig tongue was used as the antigenic substrate. In conjunction with findings published in the literature, our results can be interpreted as indicating that the activation of the basement membrane zone antigens by proteolytic enzymes is associated with an increase in antigenicity which results in the formation of "auto-antibodies" of the basement membrane zone antibody type.
| 56,855
|
Pharmacokinetics in drug therapy. I: Propranolol hydrochloride as adjunct therapy in the treatment of thyrotoxicosis.
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A case study in which propranolol hydrochloride was used as adjunct therapy in the treatment of atrial fibrillation with rapid ventricular response, thyrotoxicosis and high output heart failure is presented to illustrate the pharmacokinetics of this drug. The relationship of propranolol dosage to blood levels, the effect of blood levels on pharmacological response, the metabolism and elimination of propranolol, and determination of rational dosage of the drug, are discussed.
| 56,890
|
A new actinomycin complex produced by a Micromonospora species: fermentation, isolation, and characterization.
|
A species of Micromonospora, Micromonospora floridensis NRRL 8020, has been found to produce an actinomycin complex consisting of at least 25 active components. After solvent extraction of the complex, separation of the individual components was carried out by preparative thin-layer chromatography. Hydrolysis and subsequent electrophoretic and chromatographic identification of the amino acid content of each of the isolated components have shown differences from known actinomycins, and the probability exists that these contain a number of amino or imino acids not previously found in other members of this group of antibiotics.
| 56,917
|
Chemically-induced temperature sensitive mutants of dengue virus type 2. I. Isolation and partial characterization.
|
Temperature sensitive (ts) mutants of dengue virus type 2 (DEN-2, TH-36 isolate) were induced by replication in primary hamster kidney cells treated with 5-azacytidine. Seven ts mutants were obtained from 138 clones isolated by an immunofluorescent cloning technique. Of these 7 ts mutants, 5 were sufficiently stable to permit partial characterization. Complementation was detected at very low but statistically significant levels between some ts mutants at 40 degrees C. Viral double-stranded RNA production was evaluated in LLC-MK2 cells at 30 degrees and 40 degrees C by micro-quantitative complement fixation. The results of complementation tests and RNA production tests indicated that the 4 of 5 stable ts mutants constitute 3 separate complementation groups (2 RNA+ and 1 RNA-groups), while a fifth ts mutant was RNA- but non-complementable. The data presented here indicate that a genetic system can be developed without employing traditional plaque or cytopathology methods. Further, the 5 DEN-2 ts mutants are believed to represent the only set of complementation-positive flavivirus mutants so far isolated.
| 56,929
|
[An uncommon pseudo tumoral skin disease; the so-called Papillomatosis cutis carcinoides. A review (author's transl)].
|
The review of the current literature on the subject is followed by the exposure of the clinical and histopathological data concerning a case of papillomatosis cutis carcinoides. The Authors conclude on the opportunity to maintain this nosographic pattern, to be enclosed among the cutaneous pseudo tumoral affections.
| 56,941
|
Anaesthesia for cardioversion: a comparison of diazepam, thiopentone and propanidid.
|
Three groups of 50 patients were anaesthetized with diazepam 0.32 mg/kg or thiopentone 3.7 mg/kg or propanidid 4.6 mg/kg for elective carfioversion. Propanidid caused more hypotension than diazepam or thiopentone. Apnoea was most frequent following thipentone and excitatory side-effects were most prominent following propanidid; the electric countershock worsened the excitatory phenomena. The success rate of conversion was higher in the diazepam group than in the other groups, but the difference was not statistically significant. Diazepam failed to produce amnesia in about 33% of the patients. Thiopentone is suitable and pleasant for cardioversion. Diazepam is recommended in poor-risk patients and in emergency situations.
| 56,946
|
Primary intracranial yolk sac tumor: immunofluorescent demonstration of alpha-fetoprotein synthesis.
|
An autopsy case of 20-year-old male with primary intracranial yolk sac tumor (endodermal sinus tumor) is reported. Whereas the biopsy specimen obtained from the pineal region showed diffuse proliferation of atypical tumor cells, the metastatic subdural tumor removed from lumbar spinal region had the characteristic histologic appearance of yolk sac tumor. The histologic diagnosis was intracranial yolk sac tumor originating in the pineal gland. The elevated amount of alpha-fetoprotein in the cerebrospinal fluid and in the serum further supported the diagnosis. At autopsy, only metastatic tumor was present in the posterior fossa. The immunofluorescence study demonstrated the presence of intra- and extracellular alpha-fetoprotein globules in the tumor tissue. The intra- and extracellular distribution of alpha-fetoprotein, in general, appeared to coincide with that of the PAS-positive hyaline globules in the tumor.
| 56,986
|
Production of antisera with specificity for malignant melanoma and human fetal skin.
|
Complement-dependent cytotoxic antibodies to common cell surface antigens of cultured melanoma cells were produced in guinea pigs. At appropriate dilution, melanoma antisera were cytotoxic only to melanoma target cells. Following absorption with pooled lymphoid cells, additional absorption with melanoma cells but not absorption with fibroblasts or carcinoma cells was found to remove all cytotoxic activity from melanoma antisera. Absorption with human fetal skin cells but not with autologous fetal visceral cells was found to remove cytotoxicity from melanoma antisera. Tissue type-specific antigens may be shared by human malignant melanomas and fetal skin of black racial origin (at 16 to 18 weeks of gestation). The methods may be useful in the production of xenogeneic antisera with "operational monospecificity" for common melanoma-specific antigens. Sera from 47 patients with malignant melanoma failed to evidence specific cytotoxicity for melanoma target cells.
| 56,991
|
Effect of anti-alpha1-fetoprotein on alpha1-fetoprotein-producing rat tumors in vivo and in vitro.
|
Active or passive immunization of rats to alpha1-fetoprotein (AFP) does not consistently inhibit the growth of AFP-producing transplantable hepatomas in vivo, and anti-AFP does not kill these hepatomas in vitro. However, 3 of 14 rats in 1 experiment responded to passive immunization by reversal of tumor growth as evidenced by normalization of elevated AFP serum concentrations, and 1 of 9 rats actively immunized with rat AFP in complete Freund's adjuvant had suppressed growth of transplantable hepatoma 7777.
| 56,992
|
Isolation and characterization of an antigen of the bovine C-type virus.
|
By means of gel filtration and isoelectric focusing, an antigen of the bovine C-type leukemia virus was isolated in a highly purified form from extracts of infected cells. The antigen has a molecular weight of approximately 25,000 daltons and an isoelectric point of 6.4 to 6.6. In immunodiffusion experiments, the antigen forms a line of identity with an antigen extracted from highly purified bovine C-type leukemia virus by treatment with ether or Triton X-100. As determined by immunodiffusion analyses, the bovine C-type leukemia virus antigen does not have antigenic determinants in common with the murine or feline leukemia viruses, the foamy-like bovine syncytia virus, or the Mason Pfizer monkey virus.
| 56,993
|
Ultrastructural study of pulmonary bleomycin toxicity.
|
Ultrastructural manifestations of bleomycin A2 toxicity in the human lung were studied in three patients. In addition to the appearance of nucleolar fibrillar centers, an increase in membranous, beaded, and granular nuclear bodies was found in nuclei of type 1, type 2 alveolar epithelial cells, and interstitial fibroblasts in all treated patients. Few such nuclear bodies were found in specimens of untreated patients.
| 56,994
|
Reference interval for maternal serum alpha-fetoprotein.
|
Maternal serum alpha-fetoprotein (AFP) concentration was measured in 237 samples taken throughout the pregnancies of 28 normal pregnant women who all gave birth to normal infants. The patterns from these 28 individuals curves were compared graphically with an earlier published non-parametric 90% reference interval based upon single serum samples from other normal, pregnant women. The two "reference areas" were found to be quite similar. Maternal serum AFP values before and after induced abortion in a case of acrania and spina bifida demonstrated the value of serial maternal serum AFP quantitations in cases of suspected neural tube defects (NTD).
| 57,017
|
Thalamic evoked potentials to somatosensory stimulation in man.
|
Thalamic somatosensory evoked potentials (ThSEPs) were recorded by averaging technique from various thalamic structures during 59 stereotactic operations. From 372 records, response patterns and latency characteristics were analysed in relation to the intrathalamic localization. The findings can be summarized as follows. In N. ventro-caudalis (VC) and ventro caudalis parvocellularis (Vcpc) ThSEPs showed the most definite (and exclusively contralateral) responses characterized by a single positive (P1) deflection. The latency was shortest in VC (mean value, 17.5 msec) and in Vcpc (15.6 msec). Responses from N. centrum medianum (CM), parafascicularis (Pf) and limitans (Lim) were composed of early P1-N1 and of later P2-N2 components. The P1 latency was relatively consistent, with a mean value of 28.2 msec. Pulvinar responses showed a pattern similar to CM, with a mean P1 latency at 30.5 msec. Responses of N. dorsalis medialis (DM) were small, variable and longest, with a mean P1 latency of 54.2 msec. To ipsilateral stimulation, CM, Pul, DM and N. ventro-lateralis (VL) showed comparable wave forms. The possible role of the CM-Pf-Lim complex and of Pulvinar in the "extra-lemniscal" sensory system was considered. The usefulness of ThSEP recording to identify electrode locations in the thalamus is thus confirmed.
| 57,036
|
[Contingent negative variation in 10-year-old children. Relations with the type of performance in a task of spatial localization].
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CNV magnitude was studied in a task involving spatial localization and discrimination Subjects were 18 children 10 years of age. The CNV amplitude of half the subjects increased when the performance decreased and, in the other half, CNV amplitude decreased when the performance decreased. However, it seems that CNV magnitude increases as task difficulty increases but only above a minimal threshold varying with the subject. The results suggest that CNV amplitude cannot be related to a single psychological factor.
| 57,043
|
Single cell studies on the antibody-forming potential of fractionated, hapten-specific B lymphocytes.
|
This study addresses itself to the problem of antibody formation in vitro by mouse splenic B lymphocytes enriched for reactivity to the hapten NIP by the hapten-gelatine binding and melting technique of Haas and Layton (1975). Small numbers of NIP-gelatine-bound B cells were placed in microcultures either by bulk dispensing of dilute cell suspensions, or by micromanipulation under direct microscopic visualization. Antibody formation was induced by the T cell-independent hapten-protein conjugate NIP-polymierized flagellin, using 10(4) thymus cells per microlitre as 'filler' cells. The frequency of precursors of NIP-specific antibody-forming cells among bound cells was about 2-2 X 10(-2) (one cell in forty-five) by both statistical and direct evaluation, after adjustment for a background frequency of 6-10 X 10(-8) precursors in the thymus filler cells. Single clones commenced antibody secretion asynchronously, as shown by the fact that the incidence of positive cultures continued to rise over the whole three days of culture, and that very small clones of one to four plaque-forming cells (PFC) were still found on day 3. The mean PFC number per positive culture rose from 1-2 at day 1 to 4-7 at day 2 and about 20 at day 3.
| 57,094
|
Antigenicity of the M proteins of group A hemolytic streptococci: further evidence for shared determinants among serotypes.
|
Shared antigenic determinants between M proteins of group A streptococci appear to be widespread among serotypes. This is demonstrated by the ability of purified M proteins to absorb opsonic antibody from a variety of heterologous antisera prepared against whole cells or purified M proteins. This absorption procedure has the capacity to separate passive mouse protecting and passive hemagglutinating antibodies from opsonic antibodies measured in vitro. When whole cells or M proteins are used as heterologous absorbents, immunoglobulin may be recovered from the cells or precipitates. The recovered antibody has most of the opsonic and some of the precipitating qualities of the original unabsorbed serum, but hemagglutinating titers are significantly lower. These data provide additional evidence that shared antigenicity among M proteins can be the result of common antigenic determinants. Arguments are presented that these cross-reactions are not the result of a nonspecific protein fraction associated with purified M proteins.
| 57,101
|
[A new instruction theory: possibility of a reverse flow of information from polypeptide sequences to RNA particularly in antibody synthesis, and the mechanisms of tolerance induction and immunosuppression (author's transl)].
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A new instruction theory for antibody formation is presented. The reverse flow of information from the amino-acid sequences of small antigenic determinants to an antideterminant RNA (aRNA) seems feasible. Prerequisites are specific activating enzymes, tRNAs, ATP as well as some kind of membrane assembling the anticodons of tRNAs linearly, analogous to the linear primary structure of stretched polypeptides. Once synthesized, aRNA might be replicated, utilized as transfer factor and transcribed by means of Reverse Transcriptase into aDNA. Further steps would be the fusion of this aDNA with genetical performed DNA-molecules already coding for the basic strucures of different classes of immunoglobulins by means of a terminal deoxynucleotidyl-transferase. This could be a chromosomal or extrachromosomal integration. The second hypothesis concerns antigen-induced immunosuppression and the phenomenon of nonresponsiveness (tolerance). An overwhelming proteolysis might give rise to a degradation of antigens or receptor templates for antigenic determinants located on the surface of macrophages. On later exposure to a similar antigen proteolytic enzymes are already preformed abolishing rapidly antigenic information. The third hypothesis concerns antibody-induced immunosuppression and tolerance. Antideterminant information is integrated into the genome or established extra-chromosomally. The continuous presence of antibodies sets in motion a sequence of reactions causing an accumulation of all information intermediates including a complementary DNA strand to the aRNA. On exposure to the corresponding antigen aRNA is transcribed. However, translation might be inhibited by hybridisation with the complementary aDNA strand as well as specific RNA hydrolysis by RNase H. Concerning the immunogenity of antibodies, a proteolytical mechanism might also be possible. Taking this into account a tolerance could be suspended in the following way: 1. by influencing the overwhelming proteolytical degradation of antigenic determinants with simultaneous antigenic stimulation; 2. by substitution of aRNA to induce blocked antibody synthesis.
| 57,102
|
Histochemical localization of estrogen induced sulfated glycoprotein in rabbit uterus.
|
Histochemical localization of the estrogen-induced sulfated glycoproteins was made in the estrogen-treated rabbit uterus. Biochemical studies by a group of Endo et al, affirmed these particular glycoproteins were PAS-positive and metachromatic as stained with TB. No sign of digestion, however, has been detected in a series of tests with alpha-amylase, testicular hyaluronidase, streptomyces hyaluronidase, chondroitinase AC and chondroitinase ABC, and heparinase. The apical portions of the epithelial and glandular cells, obviously expanded by the estrogen treatment, display strong beta-metachromasia with TB (pH 4.0), saliva-resistant PAS-positive reactions, and also alcianophilia with AB (pH 2.5). These reactions are not reduced after the treatment with the enzymes above-mentioned. Meanwhile, in the stromal matrix, the same enzymes give an influence to diminish the reactions to various extent. Our results suggest that the estrogen-induced sulfated glycoprotein is definitely localized in the apical portions of the epithelial and glandular cells. The identity is emphasized between the substance that is elucidated in the histochemical sections and the sulfated glycoproteins that have been specified solely by means of biochemical assays.
| 57,108
|
Role of a lipopolysaccharide gene for immunogenicity of the enterobacterial common antigen.
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It is known that only certain strains of the family of Enterobacteriaceae, notably rough (R) mutants with the type R1 or R4 core, evoked antibodies in high titers against the common enterobacterial antigen (CA) after immunization of rabbits with heated cell suspensions. The present investigation deals with genetic and immunochemical aspects of certain R1 and R4 mutants isolated from Escherichia coli 08 and various Shigella serotypes which, unexpectedly, do not induce CA antibody formation. Immunochemical and genetical (transduction and conjugation) experiments revealed that the rough phenotype of these special mutants was evoked by a mutation of pyrE-linked rfa gene, called rfaL, which is involved in translocation of O-specific polysaccharides onto the lipopolysaccharide core. The transduction of the defective rfaL, allele into appropriate rough recipients results in transductants which have simultaneously lost the ability to evoke CA antibodies. This finding suggests that a close connection exists between the function of the rfaL gene and the expression of CA immunogenicity in R1 and R4 mutants. One of the strains synthesized neither O-hapten nor CA, suggesting a mutation in a region equivalent to the rfe genes of Salmonella.
| 57,114
|
The preparation, use, and evaluation of recorded material for teaching ultrasonics in a university Master of Science course in medical physics.
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The potential value of using recorded instructional material in a university Master's course module in medical ultrasonics is discussed. The procedure for preparation and evaluation of a program of slides with synchronized audio tape is reported. The evaluation indicates that the flexibility of this form of recorded material can make several unique contributions to the teaching program, in acquainting students with clinical problems, in simulating expensive equipment, and encouraging students to use the literature.
| 57,123
|
Inhibition of antigen-induced histamine release by ouabain.
|
The effect of ouabain, a specific sodium-potassium dependent adenosine triphosphatase (Na+-K+-ATPase) inhibitor, on antigen-induced histamine release was studied using guinea pig lung fragments sensitized in vitro with rabbit antibodies against bovine serum albumin. Histamine was assayed spectrofluorometrically. When sensitized tissue had been preincubated with ouabain (less than or equal to 1.0 x 10(-4) M) for 10 min prior to antigenic challenge, release of histamine was significantly inhibited (maximum 54%, p less than 0.001, N=9, paired t test). The most significant inhibition was obtained near the optimal concentration of antigen. The inhibition was dependent on the length of preincubation (less than or equal to 20 min), and was partially reversible upon washing the tissue removing the ouabain. Ouabain did not seem to prolong the duration of the histamine release process. Increase in potassium ion (less than or equal to 1.1 x 10(-2)M) inhibited the histamine release and had additive effects to ouabain action. Dibutyryl cyclic AMP (less than or equal to 5 x 10(-3) M), which could enhance the release, strongly antagonized the inhibition. Glucose removal from the medium did not abolish the ouabain effect. The results seem to indicate that immunologic release of histamine is under the influence of the membrane Na+-K+-ATPase activity.
| 57,130
|
Coexisting ventricular and blocked atrial parasystole.
|
A rare instance showing non-conducted atrial parasystole coexisting with ventricular parasystole is presented and a related subject is briefly discussed. The importance of recognizing parasystole is again emphasized because the ordinary extrasystoles, particularly ventricular in origin, are frequently digitalis-induced, while parasystole, which superficially resembles the ordinary extrasystoles, does not seem to be related to digitalis.
| 57,203
|
Quantitative electromyography in the detection of the carriers in Duchenne type muscular dystrophy.
|
The quantitative EMG technique was used to detect Duchenne muscular dystrophy carriers. The tests were carried out, measuring the parameters of M.U. potentials (the duration, the phase, and the 0 index according to Van den Bosch, modified by Gardner-Medwin), and using the Willison analyzer, in a group of carriers and normal subjects. Ten M.U. potentials from the deltoid, biceps brachii and quadriceps muscles were photographed and measured in each subject, and the right and the left biceps were examined with the Willison analyzer. An high detection rate was obtained by manual EMG, measuring traditional values such as mean number of phases, A.P. duration and 0 index. The Willison analyzer was significant in 2 known carriers. The total EMG detection rate was higher than the CPK tests both in the known carriers and the possible carriers. It is concluded that the quantitative EMG technique is an useful and specific test to detect carriers of the gene of Duchenne muscular dystrophy.
| 57,226
|
The Paneth cell population of the small intestine of the rat-effects of fasting and zinc deficiency on total count and on dithizone-reactive count.
|
The distribution of Paneth cells in the rat small intestine was found to be approximately one per crypt in the duodenum, two to three per crypt in the jejunum and four to six per crypt in the ileum. The ileum has more Paneth cells containing dithizone-reactive zinc than the duodenum and jejunum. Zinc deficiency had no significant effect on the total Paneth cell count but no dithizone-reactive Paneth cells were found in any area of the small intestine examined in zinc-deficient animals. Fasting for 3 days had no significant effect on the Paneth cell count but after a 4-day fast there was a significant rise in the total Paneth cell count accompanied by a fall in the percentage of Paneth cells containing dithizone-reactive zinc in all areas examined.
| 57,232
|
Effects of ethanol on the permeability of toad urinary bladder epithelium.
|
Ethanol (9%) decreases the potential difference across the toad bladder when present at the mucosal surface, the short-circuit current was unchanged. The electrical resistance decreased indicating a change in ion movements across the bladder. Unidirectional 22Na and 36Cl flux measurements showed an increase in the movement of Cl, but no change in Na. The vasopressin-induced increase in Na transport (natriferic response) was also unaffected by the presence of ethanol. It is suggested that ethanol may be altering the apical tight junctions and affecting an anion selective pathway. The hydro-osmotic response of the toad bladder to vasopressin was decreased by 70% in the presence of 3% ethanol. The hydro-osmotic action of cyclic adenosine monophosphate was also inhibited by ethanol, indicating an action subsequent to the endogenous formation of this nucleotide. Tritiated water fluxes (in the absence of an osmotic gradient) were reduced by 30% in the presence of 3% ethanol. The vasopressin-induced increase in diffusional water flow was similarly reduced. Osmotic water movements across glutaraldehyde and N-ethylmaleimide-"fixed" vasopressin-stimulated bladders were also decreased in the presence of ethanol. However, 3% ethanol had no effect on osmotic water transfer across artificial collodion membranes. Ethanol, therefore, probably interacts with the bladder membrane. The Ktrans (permeability coefficient) of ethanol and water is increased by vasopressin. suggesting that their movement is through similar pathways. It is suggested that ethanol empedes the flow of water across the toad bladder by facilitating a physicochemical interaction between the membrane "pore" and the water molecules.
| 57,235
|
Enhancement of encephalitogenic activity by the formation of myelin basic protein-brain acidic protein complex.
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Encephalitogenic protein fraction (BEC) was isolated from bovine brain tissue by extraction with salt-ethanol mixture at neutral pH, instead of employing dilute mineral acid. The fraction BEC was separated into two fractions. An acid-soluble protein was encephalitogenic and the major component was very alike to the basic protein of myelin (Al). The other was acid-insoluble acidic protein that was not encephalitogenic even at a dose of 100 mug. The acidic protein formed an insoluble complex with Al rotein which was purified by Eylar's method. Encephalitogenic activity of the complex was higher than Al protein in young guinea pigs when injected with complete Freund's adjuvant.However, this enhancement of encephalitogenic activity was not observed in aged guinea pigs. The complex showed higher blastogenic activity than Al protein alone with peripheral blood lymphocytes from guinea pigs immunized with Al protein and complete Freund's adjuvant. These results show that an adjuvant-like acidic protein is present in brain tissue and the complex with Al protein enhances the induction of experimental allergic encephalomyelitis (EAE).
| 57,252
|
Doxorubicin/B.C.N.U. chemotherapy for multiple myeloma in relapse.
|
A combination of doxorubicin ('Adriamycin") and B.C.N.U. (1,3 di[2-chloroethyl]-1-nitrosourea) (30 mg/m2 of each intravenously every 3-4 weeks) was used to treat thirteen multiple-myeloma patients who did not respond or were in relapse after remission produced by alkylating-agent/prednisone therapy. All cases were staged according to total-body myeloma-cell number and followed quantitatively for response to therapy. Seven of the thirteen patients responded (54%). Two had complete clinical remissions and a greater than 75% reduction in tumour-cell mass lasting 12 and 16 months. Five others had partial remissions with lesser degrees of tumour-mass reduction and bone pain and improved haemoglobin and serum-albumin concentrations. Toxicity was limited to occasional myelo-suppression, mild alopecia, and nausea. The results indicate the usefulness of doxorubicin/B.C.N.U. for myeloma patients who have relapsed during previously effective alkylating-agent therapy.
| 57,335
|
Relation between postphlebitic changes in the deep veins and results of surgical treatment of venous ulcers.
|
41 patients with venous ulceration, investigated by ascending phlebography, had operations to ligate incompetent calf perforating veins. Recurrent ulceration developed within five years of operation in all 23 patients with evidence of deep-vein damage on the initial phlebograms. Only 1 of the seventeen patients with normal deep veins had a recurrent ulcer during the same period of follow-up. Thus local surgery to the perforating veins in postphlebitic limbs was shown to be ineffective.
| 57,339
|
Man in transit: Biochemical and physiological changes during intercontinental flights.
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Fifteen members of the passengers and crew of a plane flying from Buenos Aires to London have been studied, before, during, and after the 20-hour flight. Even allowing for circadian variation, there were clear rises in the urinary excretion of noradrenaline in the first part of the flight, and of both noradrenaline and adrenaline in the 2 days afterwards.
| 57,437
|
Breast and thyroid cancer and malignant melanoma promoted by alcohol-induced pituitary secretion of prolactin, T.S.H. and M.S.H.
|
In interview data from the U.S.A.'s Third National Cancer Survey, alcohol ingestion was associated with a higher occurrence of cancers of the breast, thyroid, and amlignant melanoma. Data from other studies support the first two associations. A unifying hypothesis to explain these seemingly diverse associations suggests that alcohol stimulates anterior pituitary secretion of prolactin, thyroid-stimulating hormone (T.S.H.), and melanocyte-stimulating hormone (M.S.H.). Under the stimulations of these hormones, the three target tissues exhibit increased mitotic activity and hence an increase susceptibility to the development of a malignancy. A wide variety of findings from other studies indicate plausibility for this hypothesis. The implications could be grave. In addition to alcohol, several common drugs acting in similar manner could be cancer promoters, including: resperine, methyldopa, phenothiaznes, d-amphetamine, tricyclic antidepressants, and antihistamines. Over 20000 (25%) ofall new breast-cancer cases each year in the U.S.A. could be preventable if this hypothesis is correct.
| 57,445
|
Place of azathioprine for Crohn's disease.
|
The clinical effects of azathioprine have been compared with those of corticosteroids in a group of 112 patients who have come under the care of a single unit between 1963 and 1975. There is no clear evidence that azathioprine alters the course of the disease in the long term; it is of value in obtaining a remission, particularly when the disease affects the large intestine.
| 57,449
|
Variable response to long-term 1alpha-hydroxycholecalciferol in haemodialysis osteodystrophy.
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Ten uraemic patients on regular haemodialysis were treated with 1alpha-hydroxycholecalciferol (1alpha-H.C.C.) for 5 to 14 months. Five patients who had histological osteitis fibrosa with or without osteomalacia responded well, with resolution of musculoskeletal pain, return of raised serum-alkaline-phosphatase concentrations to normal, resolution of radiological subperiosteal erosions, and improvement in histological signs of osteitis fibrosa and osteomalacia. In these patients 1alpha-H.C.C. proved a safe and effective drug. Five other patients did not improve. Characteristically these patients started with moderately severe histological osteomalacia and minimal, if any, osteitis fibrosa. Proximal myopathy was a prominent symptom and serum-alkaline-phosphatase was normal in four of them. Treatment with 1alpha-H.C.C. resulted in early troublesome hypercalcaemia, and repeat bone histology 5--11 months later showed no improvement. It is suggested that in these patients lack of 1,25-dihydroxycholecalciferol may not have been wholly responsible for the observed osteomalacia, hence 1alpha-H.C.C. alone was ineffective. Phosphate depeltion may have been an important contributing factor.
| 57,505
|
Comparison of antibody responses and reactivity of "Alice" and WRL 105 strain live influenza vaccines.
|
Groups of 45 adult volunteers were vaccinated intranasally with a single dose of either "Alice" or WRL 105 strain live influenza vaccines. Seroconversion rates against A/Scotland/840/74 were significantly greater following administration of WRL 105 but seroconversion rates against A/England/42/72, A/Port Chalmers/1/73, A/Finland/4/74, A/Victoria/3/75, and A/England/864/75 did not differ significantly between the two vaccines. Poor antibody responses were elicited by both "Alice" and WRL 105 strains against A/Victoria/3/75 and A/England/864/75. No severe reactions followed the administration of either vaccine.
| 57,520
|
[Tumor antigens in the diagnosis of gastroenterological diseases (author's transl)].
|
History, biochemical properties, techniques and normal range of carcino-embryonic proteins and their applications in clinical diagnosis are reviewed in detail. The importance of alpha1-fetoprotein, colon embryonic antigen, fetal sulfoglycoprotein, alpha2H-globulin and Regan-isoenzyme of alkaline phosphatase is discussed for carcinomas of the gastrointestinal tract, other malignant tumors and benign gastroenterological diseases. The results of prospective studies in cancer high risk patients and the indications for the determination of carcino-embryonic proteins in gastroenterology were described.
| 57,561
|
[Experiments with splenohepatoplasty in the rat].
|
The physiopathological premises for various methods of hepatic revascularisation are described and results wiht splenohepatoplasty in 40 rats are presented. This operation involves insertion of the upper pole of decapsulated spleen in the left hepatic lobe to create a new parenchymal supply and regenerate the liver cell. The clinical, functional and anatomopathological data are discussed. The experimental value of the procedure is asserted, though it is felt that no sure demonstration can be given of the establishment of newly formed vascular connections between the two organs.
| 57,580
|
Efficacy of tri-tab (T3 uptake diagnostic kit) under extreme temperature conditions.
|
A new surface adsorbent technique has been compared with the widely used resin sponge T3 uptake method. The new technique has the desired attributes, correlates very highly with the resin sponge method (r = 0.93) and has been accepted as a simple, rapid and reliable method under normal temperature conditions. However, under extreme conditions (0-20 degrees C and 30-60 degrees C) the test is unreliable.
| 57,627
|
Serologic differences in strains of Sporothrix schenckii.
|
To obtain evidence that Sporothrix scheneckii enters the body by contact with contaminated materials, the antigenic property of strains from different sources was investigated. The reciprocal absorption test of the antisera against a soil isolate and a human isolate (KO 4606) showed that the absorbed antisera against KO 4606 possessed unique antigen(s) in addition to the common antigen of both strains. Twenty-three clinical isolates were tested with absorbed antisera. Not all of them possessed the unique antigen(s), but there were serologic varieties among S. schenckii strains, regardless of their sources, clinical type of the disease and the morphology of the yeast phase cells.
| 57,646
|
[Lipodystrophia intestinalis (Whipple's disease)--a rare origin of a sprue syndrome].
|
An own case of lipodystrophia intestinalis (Whipple's disease) of a male patient who was 41 years old at the time of the first admission is reported and discussed using literature. The biopsy of the small intestine is of decisive importance for the establishment of the diagnosis as well as for the long-term therapy with antibiotics (1 g oxytetracycline a day).
| 57,673
|
[Reflex-dystrophic pseudo-arthritis or Sudeck syndrome (author's transl) ].
|
Local bone- and tissue dystrophies identical with Sudeck's syndrome and progressing in 3 stages are called reflex dystrophies. In the 1st and 2nd stages complete recovery is possible, in the 3rd stage only irreversible dysptrophic-ankylosing defect-healing. Etiologic significance of causal factors discussed is not certain. In, initially similar, inflammatory and rheumatic arthritis often only the further course and radiologic appearance provide a diagnosis. So far we have no desirable clear definition of reflex dystrophic conditions.
| 57,675
|
[Sub-ppm determination of thiouraciles applicated as thyreostatics in meat by high pressure liquid chromatography (author's transl)].
|
The thyreostatics 2-thiouracile, 4-methyl-2-thiouracile, and 2-propyl-2-thiouracile were extracted from meat and determined by High Pressure Liquid Chromatography to a limit of about one ppb.
| 57,680
|
Mortality after laparotomy. A 10-year series.
|
The Department of Surgery at the University Hospital, Linköping has 133 beds and serves a population of 130000. During the 10-year period 1962-1971 35039 in-patient operations were performed, of which 16719 (48%) were laparotomies. If fracture surgery and urological operations are excluded (during the relevant period these specialties were included under General Surgery) the proportion of laparotomies becomes 67%. Of patients subjected to this procedure 431 (2.58%) died. The mortality for appendicectomy was 0.2%, for gall-bladder surgery 1.3%, for gastric surgery 8.1%, for colon surgery 11.9% for small-gut surgery (including ileus) 15.2%, and for pancreatic surgery 22.2%. Over and above the target organ, malignancy and age exceeding 50 years appear to have contributed greatly to a lethal outcome.
| 57,687
|
Malignant lymphomas of the salivary glands. Review of the literature and report of 33 new cases, including four cases associated with the lymphoepithelial lesion.
|
Malignant lymphomas involving major salivary glands have been reported to occur in 31 cases. To these, we add 33 cases, 17 of which were studied in detail from the points of view of clinical presentation, classification (Rappaport), staging (Ann Arbor), therapy, and subsequent course. The parotid gland was involved much more frequently than the submandibular gland. No example of sublingual gland involvement was discovered in the present series. Most of the patients were in the sixth and seventh decades of life. Noteworthy is that all sub-types of lymphosarcoma were encountered, with only a single case of Hodgkin's disease present. In four of the patients, the characteristic histologic picture of lymphoepithelial lesion was found in juxtaposition to malignant lymphoma. The majority of patients received one or more courses of postoperative radiotherapy, which offered the best chance for long-term remission. However, only 40% of patients were free of disease after two years.
| 57,714
|
Acute monocytic leukemia. Cytologic, histologic, cytochemical, ultrastructural, and cytogenetic observations.
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A case of acute monocytic leukemia (AMoL) studied by cytologic, histologic, cytochemical, ultrastructural, and cytogenetic technics is reported. The immature monocytes were characterized by strong fluoride-sensitive nonspecific esterase activity. Nuclear irregularity, prominent nucleoli, erythrophagocytosis, and pinocytosis were observed on transmission electron microscopy, whereas broad-based ruffles, similar to those found on normal monocytes, were identified with scanning electron microscopy. Cytogenetic analysis showed an 8/9 translocation and four or five identical 8p- marker chromosomes in most bone marrow cells.
| 57,715
|
Senile ectropion and entropion: a comparative histopathological study.
|
A microscopic histopathological study was done on 500 full-eyelid-thickness surgical specimens: 25 with the diagnosis of senile ectropion and 25 with that of senile entropion. Five different staining techniques were used. There appears to be significantly more orbicularis and Riolan's muscle ischemia, atrophy, and collagen fragmentation with ectropion than with entropion. Entropion shows more septal and tarsal atrophy. In both conditions, the skin and conjunctiva show chronic inflammation and scarring as a constant feature. Statistical significance at the 1% level was present for all six characteristics studied. These histopathological changes, if not etiological, are at least concomitant features differentiating senile ectropion from entropion at the microscopic tissue level.
| 57,735
|
Observations on the automated calculation of radioimmunoassay results.
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Radioimmunoassay standard curves derived by four different automated calculation methods are compared with those derived manually for five assays of clinical importance (thyroxine, triiodothyronine, thyrotrophin, alphafetoprotein, and human growth hormone). The three curve fitting methods (linear or cubic regression on log x versus logit y, cubic regression on log x versus y) produced considerable distortion of the manually derived curves, which in some cases could have impaired the accuracy of an estimate in a clinical sample and altered the clinical interpretation. Distortion patterns varied with the particular antigen assayed and with experimental conditions. In contrast, a simple linear interpolation method produced little distortion and gave results which were close to those derived manually in each assay examined.
| 57,737
|
Production, isolation, and properties of azetomycins.
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Streptomyces antibioticus synthesizes five actinomycins that differ in the "proline site" of the molecule. When cultured in the presence of azetidine-2-carboxylic acid (AzC), antibiotic synthesis was stimulated 40 to 50%, synthesis of actinomycin IV was inhibited, and one or both prolines were replaced by AzC. AzC incorporation could not be reversed by concomitant supplementation with proline or sarcosine, and only pipecolic acid affected a minor reversal of AzC incorporation. AzC-containing actinomycins were isolated and designated azet-I and azet-II; a third unresolved component or mixture was called azet-III. The molar ratio of AzC to proline was: azet-I, 1:1; azet-II, 2:0. Azet-III was equivocal. These azetidine actinomycins (azetomycins) were found to be potently inhibitory to the growth of selected gram-positive but not as potent to the growth of gram-negative organisms. The relative inhibitory affect against growth and ribonucleic acid synthesis in Bacillus subtilis was: actinomycin IV =/> azet-I > azet-II >>> azet-III. Protein synthesis was affected similarly; however, kinetic studies with B. subtilis revealed that ribonucleic acid synthesis was inhibited rapidly followed by an inhibition of protein synthesis. At concentrations less than 1 mug/ml, deoxyribonucleic acid synthesis was stimulated by these actinomycins.
| 57,738
|
[Subtypes of serum hepatitis B antigen].
|
Rheophoresis improved gel diffusion technique was used for the determination of subtypes of HB antigen (HBAg) according to D (ad + y) and Y (ay +, d--) specificity. Although the relative small number of carriers of antigen was investigated, it seems that the distribution of subtypes is somewhat different from the results found by the american and scandinavian autors and is more similar to the results of Hadziyannis (Greece) and Mosley in Israel. The specifity of serum containing HB antibodies was also investigated. Five sera containing antibodies, revealed both ad and ay subtypes by the counter electrophoresis method, but two of them showed a significantly stronger precipitation line with subtype ay.
| 57,774
|
Excitability of human motoneurones after discharge in a conditioning reflex.
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A new method of exploring the H reflex excitability cycle is proposed which permits the exploration of motoneurones that discharged in response to the conditioning shock. This is made possible by using a test stimulus supramaximal for the alpha motor fibres of the nerve, which causes a collision in the alpha fibres between the orthodromic conditioning reflex volley and the antidromic motor volley. As a result of this collision, a test reflex contraction appears in the EMG, due to motoneurones that have already discharged in the conditioning response. This method permits studies in human subjects of the poststimulus refractory period of motoneurones as well as the early inhibitory phenomena related to the conditioning stimulus and response. It is shown that during the initial period of the classical H reflex excitability cycle, the test shock explores only alpha motoneurones corresponding to a fringe of cells subliminally excited by the conditioning stimulus. The difference between the populations of motoneurones tested by the two methods explains the differences between the features of the cycles obtained.
| 57,856
|
Regulation of slow potential shifts in nucleus reticularis thalami by the mesencephalic reticular formation and the frontal granular cortex.
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Novel stimuli or electric stimulation of the mesencephalic reticular formation (MRF) produced large positive slow potentials (SPs) in rostral nucleus reticularis thalami (RVA) that accompanied the negative SPs known to occur in frontal cortex. SP durations (20-30 sec) were similar to the periods of unit inhibition that occur in RVA following MRF stimulation. Trains of 8 c/sec medial thalamic stimuli produced phasic negative SPs in RVA similar in duration to the intervals of unit excitation that follow each stimulus pulse. These results suggest that the polarity and duration of the SPs in RVA reflect changes in excitation of the underlying neurons. Direct activation of a specific region of RVA produced complete inhibition of visual cortex responses evoked by optic tract stimuli, a finding which suggests that RVA has an inhibitory action on the thalamus. A tone reinforced by electric shock also elicited SPs in frontal cortex (negative) and RVA (positive). In contrast to the long duration of the MRF- or novelty-elicited SPs, the durations of the conditioned SPs were phasic and were regulated by the tone--shock interval. Bilateral cryogenic blockade of the interconnections between the frontal cortex and medial thalamus abolished SPs of all origins in the frontal cortex. The blockade also abolished conditioned SPs in RVA, but did not affect the MRF-elicited ones. Thus, the subcortical SPs that accompany orienting to novel stimuli are distinct from those which occur during the higher cognitive process of conditioned expectancy and require the integrity of the mediothalamic-frontocortical system.
| 57,857
|
Further studies on the possibility of differential demonstration of radicals of sulphur-containing amino-acids.
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The authors showed that in rat liver and brain sections with blocked SH groups and split S-S bonds mercury orange stains some tissue structures after treating the sections with BAL. Considering that the blockade of SH groups with N-ethylmaleimide in is stable the authors set forth the hypothesis that the use of BAL may enable the demonstration of a sulphur-containing amino-acid which is devoid of SH or SS groups but acquires them only when acted upon by BAL. The in vitro studies demonstrated that the effect of BAL makes it possible to stain methionine with mercury orange which otherwise does not stain this amino-acid.
| 57,909
|
A neutral subtilopeptidase inhibitor from porcine serum some evidence for alpha2-macroglobulin.
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An inhibitor of neutral subtilopeptidase [EC 3.4.24.4] was purified from porcine serum by salting out with (NH4)2SO4, chromatography on anion exchange sephadex, gel filtration with Sepharose 6B, and isoelectric focusing. The preparation was homogeneous by electrophoretic and ultracentrifugal criteria, and was shown to be a glycoprotein with a molecular weight of 740,000. It inhibited the caseinolytic activities of thermolysin, subtilisin, trypsin [EC 3.4.21.4], and alpha-chymotrypsin [EC 3.4.21.1] as well as that of neutral subtilopeptidase by an equimolar binding to those proteolytic enzymes. SDS-polyacrylamide gel electrophoresis after reduction with beta-mercaptoethanol indicated that the inhibitor was made up of four subunit monomers having a molecular weight of 190,000. From comparisons of its physiocochemical and inhibitory properties with those of well-investigated plasma proteins, the inhibitor was identified as alpha2-macroglobulin. On treatment of the inhibitor with neutral subtilopeptidase, a protein with a molecular weight of 95,000 appeared after treatment with SDS and beta-mercaptoethanol, suggesting that a peptide bond susceptible to the enzyme exists near the mid-point of the subunit chains.
| 57,960
|
Immunoassay of human TSH using dried blood samples.
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A sensitive, semi-quantitative radioimmunoassay method to screen for elevations of TSH concentration in blood is described. The method requires two 0.32 cm dots of dried blood-impregnated filter paper (equivalent to 3 mul plasma) and a 3-day incubation. Separation of bound and free is obtained using polyethylene glycol. The method can recognize TSH concentrations as low as 22 muU/ml using a highly sensitive antiserum developed by one of us (AFP). TSH in dried cord and newborn blood from 4 infants with congenital hypothyroidism was clearly higher than in normal infants. The method is suitable for use in a newborn screening program to confirm the suspicion of primary hypothyroidism in specimens with low T4 concentrations.
| 57,965
|
Volatilization of lindance from water in soil-free and flooded soil systems.
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Volatilization of 14C-lindane from water in planchets and under flooded soil ecosystem was investigated. Lindane disappeared faster than parathion from planchets. More rapid loss of both insecticides occurred from water than from chloroform. Loss of lindane and parathion was related to measured losses of water by evaporation. During 5-day incubation under flooded soil conditions, disappearance of lindane was faster from open vials than from sealed vials, whereas in nonflooded soil, no volatile loss of the insecticide was evident despite water evaporation. Over 5 day incubation under flooded conditions, greater volatile loss of lindane occurred in sandy soil than in alluvial soil apparanetly due to greater adsorption to the soil colloids decreasing the insecticide concentration in the standing water on the laterite soil. Under identical conditions of water evaporation, lindane loss was directly proportional to its initial concentration in the water. These results suggest that considerable loss of soil applied pesticides can occur by volatilization from the standing water in flooded rice fields, particularly under tropical conditions.
| 57,974
|
Early diagnosis of neonatal bacteremia by buffy-coat examination.
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This study demonstrates the value of the buffy-coat smear examination in the early diagnosis of neonatal bacteremia. It is inexpensive, easy to perform, and relatively efficient. In most situations large numbers of bacteria could be seen in each positive smear. Unfortunately, the presence of a positive buffy-coat smear was often associated with a poor prognosis; more than one half (four of seven) of infants with positive smears died.
| 58,058
|
Mechanism of release of active alpha subunit from dimeric alpha beta avian myeloblastosis virus DNA polymerase.
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Storage of the dimeric (alphabeta) form of avian myeloblastosis virus (AMV) DNA polymerase in glycerol resulted in the release of the smaller alpha subunit, as detected by glycerol gradient sedimentation. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of enzyme stored in glycerol showed the concomitant appearance of several polypeptides and a lowering in the level of both beta and alpha components. This reduction appears to be the result of cleavages introduced by traces of hydrolytic activity present in glycerol samples. An enhancement of alpha subunit released, as detected by activity profile, was also achieved upon direct but limited exposure of purified avian myeloblastosis virus DNA polymerase to carboxymethyl-cellulose-bound trypsin matrix. Electrophoretic analysis of digested enzyme revealed a progressive fragmentation, with simultaneous increase in the alpha subunit and decrease in the beta subunit.
| 58,080
|
Radiommunoassays for the 70,000-molecular-weight glycoproteins of endogenous mouse type C viruses: viral antigen expression in normal mouse tissues and sera.
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Genetic information coding for type C RNA viruses is transmitted within the DNA of mouse cells. At least three endogenous viruses have so far been immunologically distinguished by radioimmunoassays for their 12,000-molecular-weight polypeptides (p12). In the present study, the 70,000-molecular-weight glycoproteins (gp70) of three prototype viruses were purified, and competition radioimmunoassays were developed for each. By use of these immunoassays, the antigenic determinants of gp70's of different classes of endogenous virus, isolated from the same and from a variety of other mouse strains, were readily discriminated. In contrast, viruses of the same class were indistinguishable. These findings further document the existence of three distinct endogenous viruses of mouse cell. The levels of type C viral gp70 were quantitated in tissues and sera of several inbred strains. The pattern of immunological reactivity of the gp70 detected in serum was indistinguishable from that of the viral gp70 partially purified from tissues of the same strain. Moreover, in each case it was indistinguishable from that of a specific class of endogenous virus. In virus-negative tissues of BALB/c and NIH Swiss mice, the viral gp70 detected was shown to be representative of a class III endogenous virus whose p12 polypeptide was also expressed by the same cells.
| 58,081
|
[Recent details of the frequency and immunologic reactivity of sympathetic ophthalmia (author's transl)].
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When giving details of the frequency of Sympathetic Ophthalmia a clear distinction must be made between this disorder and the Phacogenic Ophthalmia also affecting the second eye. The latter is found with lens damage, whereas genuine Sympathetic Ophthalmia in relation to enucleation, eye damage and eye opening surgery at Heidelberg University between 1937 and 1973 is less than 1%, a figure markedly below figures quoted in the earlier literature. In two out of three patients with recent genuine Sympathetic Ophthalmia we found an augmented stimulation index in the LTT with retina antigen, not choroid antigen, as compared to control groups. This can be regarded as due to an individually augmented immunologic reactivity towards eye specific tissue antigens.
| 58,086
|
Death in acute upper gastrointestinal bleeding. Can endoscopy reduce mortality?
|
In a retrospective analysis of 64 deaths from acute upper gastrointestinal bleeding in Edinburgh Royal Infirmary, 46 of the patients (72%) were found to have been over 60 years of age. Recurrent or continuous bledding occurred in 24 cases; after exclusion of deaths from sudden exsanguination (9) and from bleeding varices with subsequent hepatic failure (11), only 4 patients died from recurrent bleeding. Other causes of death were postoperative complications (20) and other severe concomitant disease (20). These results suggest that improved diagnostic techniques such as endoscopy may not significantly reduce the mortality from acute upper gastrointestinal bleeding.
| 58,212
|
Pathogenesis of essential hypertension.
|
It is proposed that essential hypertension is an exaggeration of the tendency for blood-pressure to rise with age, that it results from a repeated sequence in which a small rise in pressure, possibly resulting from an autonomic nervous overactivity, produces changes in the kidney which maintain the rise of pressure and become the basis for a further rise.
| 58,262
|
Evidence of an agent transmissible from ulcerative colitis tissue.
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Five New Zealand White rabbits were injected intracolonically with homogenates (100 mum) of ulcerative-colitis tissue. Histological changes closely similar to those seen in the human donors were present in the mucosa and submucosa of the large intestine of four of these rabbits 3-12 months later. Similar changes were seen in the large intestine of three of four rabbits 6-13 months after intravenous or intracolonic inoculation of homogenates of rabbit mesenteric lymph-nodes after passage of human ulcerative colitis tissue (100 mum or 0.2 mum). Three of thirty A2G strain mice injected with similar tissue homogenates (100 mum or 0.2 mum) from patients with ulcerative colitis into the footpad or intraperitoneally, had granulomatous changes in footpad, bowel, liver and/or spleen 3-22 months later. Such changes did not develop in rabbits or mice inoculated with tissue from normal controls. The results of these experiments suggest that a transmissible factor is involved in the aetiology of ulcerative colitis.
| 58,307
|
Localization of alpha-fetoprotein in liver tissue of rats during postnatal development: comparison of the immunofluorescent and autoradiographic methods.
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Localization of alpha-fetoprotein has been followed in the liver of rats of the Wistar strain from birth up to 37th day of life, and its presence was detected by means of the immunofluorescent and the autoradiographic methods. The former has shown alpha-fetoprotein to be localized in hepatocytes and the number of positive hepatocytes to decline proportionally with that of alpha-fetoprotein concentration in the serum. In newborn rats almost all the hepatocytes were found to be positive. During the course of the subsequent development of the liver tissue the number of positive hepatocytes decreases and at the time of the formation of the lobular structure only certain groups of lobes remain positive. The number of positive cells, gradually diminishes from the periphery towards the vena centralis. The autoradiographic method revealed only small groups of individual cells to be alpha-fetoprotein positive, without any specific localization.
| 58,388
|
Labelling of bleomycin with cobalt-57, indium-111, technetium-99m, mercury-197, lead-203, and copper-67.
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The radiochemical purity of the cobalt-57 complex of bleomycin could be enhanced by adjusting the pH of the final product to a value between 5 and 6. This radiopharmaceutical appeared to have better tumor visualizing properties compared to the not neutralized preparation. The clinical use of the cobalt-57 bleomycin complex is however limited by the long physical half-life of the label, causing a risk of radioactive contamination. It appeared to be possible to label bleomycin with radioactive cations (111In3+, 99mTc4+, 197Hg2+ and 67Cu2+) having suitable gamma ray energies and short half-lifes. These bleomycin complexes showed a high radio-chemical purity judged by their behaviour on thin layer chromatography, paper chromatography, and electrophoresis, but their application as tumor visualizing radiopharmaceutical turned out to be disappointing compared with cobalt-57 bleomycin.
| 58,409
|
Human pituitary growth hormone: restoration of full biological activity by noncovalent interaction of two fragments of the hormone.
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The NH2-terminal 134 amino-acid fragment of the reduced-carbamidomethylated human somatropin molecule is found to react noncovalently with the COOH-terminal 51 amino-acid fragment in solutions of pH 8.4 at 2 degrees to restore full biological activity as evidenced by the rat tibia and pigeon crop-sac assays. In addition, circular dichroism spectra of the recombinant show the conformation to be completely repaired in comparison with that of the native hormone.
| 58,417
|
The 1971-72 epidemic of acute viral hepatitis in Godthaab, Greenland.
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Viral hepatitis has been known to occur among the Greenland population endemically as well as in smaller and larger epidemics. A large epidemic of acute hepatitis comprising around 9% of the entire population, viz. more than 4000 notified cases, swept through Greenland between October 1970 and December 1972. 996 verified cases were seen in the Godthaab district and subjected to more detailed studies. Most of the Godthaab cases were seen among children and adolescents, and no disease was observed in children less than one year of age. Out of 996 diagnosed cases 9 showed acute hepatic failure with coma. Two further cases of hepatic coma were referred for treatment from outside the district. Three of these 11 patients recovered spontaneously. Of the residual 8 cases 6 were treated with exchange transfusions and steroids. Four of these survived and recovered completely. No lasting sequelae had been registered in any of the surviving cases of the epidemic up to June 1975 (2 1/2 years after cessation of the epidemic). Prophylaxis with gamma-globulin was undertaken in a medium-sized settlement in which practically the entire population received gamma-globulin when the first case of hepatitis was diagnosed. In this settlement only 7 out of 297 inhabitants contracted hepatitis. By contrast, in a similar settlement where no gamma-globulin was given, more than 30% of the population developed icteric hepatitis. The clinical features and the prophylactic effect of gamma-globulin seem to indicate that the epidemic was caused by the hepatitis A virus. In accordance with this, transitory Australia-antigenaemia was demonstrated in the acute phase in only 2.6% of the cases, possibly inidicating a small admixture of acute hepatitis type B to the epidemic predominantly caused by hepatitis A virus.
| 58,437
|
The DNA provirus hypothesis.
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I have discussed the observations and experiments that led to the formulation and establishment of the provirus hypothesis and the DNA provirus hypothesis, which includes RNA-directed DNA synthesis for the formation of the provirus. I have also discussed some aspects of the present status of our knowledge of the mechanism of formation of the DNA provirus both to point out the work remaining to be done and to illustrate hypotheses for the origins of ribodeoxyviruses and the origins of other animal enveloped RNA viruses and of animal small DNA viruses. Finally, I have indicated that I do not believe that infectious viruses cause most human cancers, but I do believe that viruses provide models of the processes involved in the etiology of human cancer.
| 58,444
|
Assay of androgen binding sites by exchange with methyltrienolone (R 1881).
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Methyltrienolone (R 1881 - 17beta-hydroxy-17alpha-methyl-estra-4,9,11-trien-3-one) binds specifically to androgen receptor in rat prostate cytosol where, unlike androstanolone, it is not metabolized. By exchanging bound endogenous hormone in rat prostate cytosol with labelled R 1881, it is possible to measure total (free anc occupied) binding sites. This assay method has also been applied to the measurement of androgen receptor sites in human benign prostatic hypertrophy where R 1881 has the added advantage of not being bound by any contaminating plasma protein (sex hormone binding protein).
| 58,452
|
[Karyotypic analysis of human cell lines (CaVe and HeLa) by the method of differential staining of chromosomes].
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Karyological analysis of CaVe (human stomach cancer) and HeLa cell lines was carried out by means of differential Giemsa staining. In the CaVe cells 12 marker chromosomes were revealed, seven of them similar to those found in our HeLa cell strain. Four markers in our HeLa subline and seven in CaVe cells were similar to those of HeLa sublines described in literature. The authors have arrived at the conclusion that the CaVe line isolated in 1961 was contaminated and now represents a variant of HeLa cell line.
| 58,478
|
[Sensitivity of m. kansasii strains to various antibiotics and chemotherapeutics in vitro and in vivo (author's transl)].
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Sensitivity of 40 strains of M. kansasii (var. luciflava) to various antibiotics and chemotherapeutics in vitro and in vivo was examined. The strains showed considerable individual variability in their susceptibility in vitro, most were more resistant to isoniazid and PAS and about one half of the investigated strains to streptomycin, too, if correlated to "wild" strains of M. tuberculosis. Susceptibility to ethionamide, thiosemicarbazone (Conteben), viomycin, kanamycin and cycloserine appears to be the same as in the case of M. tuberculosis strains, but the resistance to pyrazinamide is higher. Good effect has been observed in vitro with rifampicin, ethambutol, capreomycin and phenazine derivative B 663. Oleandomycin and gentamycin are ineffectual in the dosages of drugs we used. The activity of most of these drugs was observed in experimental infections of white mice--in mono-therapy and in various combinations-provoked by different strains of M. kansasii. The main criterion of the effectivity of the treatment was the enumeration of viable mycobacterial units in the lungs of the mice in ten-days intervals; in one part of the experiments the histological examination of the various organs of the mice was performed. The drugs of the I. and II. line of antituberculotics were ineffective or showed only a slight effect. A very good effect of rifampicin, ethambutol and phenazine derivative B 663 in monotherapy and in multiply drug therapy was observed.
| 58,490
|
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