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RNA-metabolism in Streptomyces hydrogenans. Effect of 20beta-hydroxysteroid-dehydrogenase inducing dienediol on RNA-content and RNA-profile.
|
For the isolation of RNA and polysomes, logarithmically growing cells were disrupted by grinding with kieselgur. Other methods failed to produce undergraded m-RNA as shown by 10-50% sucrose gradient-centrifugation and electrophoresis in 2% mixed agarose-acrylamide gel columns. RNA was extracted by a modified phenol method or in presence of DEP. After the application of dienediol, the amount of acid precipitable RNA decreased by 20 to 50% in 20 min. Incorportation of precursors into RNA was much slower immediately after induction but increased during the next two hours. Three hours after induction there was no difference in the RNA-content of induced and control cultures. Degradation of stable as well as of unstable RNA was observed. Simultaneous addition of the inducer and rifamycin inhibited the production of 20beta-STDH suggesting the synthesis of special m-RNA. The effects of some other antibiotics have also been studied. The existence of a specific m-RNA in the induced system was established from differences in the 3H/14C quotients of gel fractions in the region between light r-RNA and t-RNA.
| 58,544
|
Bacillus subtilis RNA polymerase and its modification in sporulating and phage-infected bacteria.
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Bacillus subtilis RNA polymerase holoenzyme consists of the subunits beta', beta, sigma, alpha, delta, and omega. In sporulating bacteria and in bacteria infected with phages SP01 and SP82, this enzyme undergoes changes in subunit composition and transcriptional specificity that could play a regulatory role in gene transcription. Sporulating bacteria may contain a specific component that inhibits the activity of the sigma subunit of polymerase probably by interfering with the binding of sigma-polypeptide to core enzyme. The hypothetical inhibitor may be metabolically unstable, since its activity is rapidly depleted from sporulating cells in the presence of chloramphenicol. Inhibition of sigma-polypeptide activity may restrict the transcription of phage DNA an infected sporulating cells. Although lacking the sigma-subunit, RNA polymerase purified from sporulating cells contains sporulation-specific subunits of 85,000 and 27,000 daltons. In SP01-infected bacteria, the sigma-subunit is replaced by phage-induced subunits. Purified enzyme containing the protein product of SP01 regulatory gene 28 directs the transcription of phage middle genes in vitro, while enzyme containing phage-induced polypeptides V and VI preferentially copies late genes. Accurate transcription of middle and late genes in vitro requires the host delta-subunit of polymerase (or high ionic strength) but not sigma-subunit. Phage PBS2 induces an entirely new multisubunit RNA polymerase that specifically transcribes PBS2 DNA in vitro. This enzyme is synthesized de novo after infection and does not arise by modification of the B. subtilis holoenzyme.
| 58,549
|
Non-specific passive desensitization XX: two important technical details.
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For non-specific passive desensitization to be effective two steps are necessary: (1) dialyze concentrated gamma globulin precipitated from plasma or serum by ammonium sulfate and (2) allow time for complete recovery from the initial reaction to antigen aerosols before giving the desensitizing dose of gamma globulin.
| 58,571
|
Induction of tolerance in adult guinea-pigs by two antigen dosage levels and by antigenic competition.
|
The effect of prior injection of increasing doses of dinitrophenylated bovine serum albumin (DNP-BSA) mixed in Freund's complete (FCA) or incomplete (IFA) adjuvants on the antibody response to a subsequent challenge with an optimal immunizing dose of DNP-BSA in FCA has been examined and compared with the effect of competition with the unrelated antigen bovine gamma-globulin (BGG). An unresponsive state was induced by pretreatments with either a minimal dose of antigen, a large antigen excess or a competitive mixture in FCA. The specificity of this unresponsiveness was ascertained by the normal response of pretreated animals to the unrelated antigen arsanilic-human albumin (ARS-HSA). Prior injection of either a minimal dose (0,2 mug), an antigen excess (20 mg) of DNP-BSA or an optimal dose (20 mug) of DNP-BSA mixed with an excess of BGG, incorporated in IFA, also induced a specific tolerance to DNP-BSA. The former treatment induced a low zone tolerance whereas both later treatments induced a high zone tolerance.
| 58,574
|
Antithymocyte globulin in renal transplant recipients. Report of a prospective randomized controlled trial.
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Horse antihuman thymocyte globulin (HAHTG) combined with prednisone and azathioprine (lmuran) was used as immunosuppressive therapy in a randomized controlled sutdy in 50 renal allograft recipients. Side effects of HAHTG administration given intravenously were mostly mild. In the treated group, four patients out of 26 died of infectious complications, whereas in the control group, three patients out of 24 died of infectious complications (chi2 = .01,P greater than .05). The graft survival at 18 months was ten of 24 in the control group and ten of 26 in the treated group (chi2 = 1.26, P greater than .05). Cumulative graft survival was 58.3% in the control group and 38.1% in the treated group at 18 months. However, if we consider the people who died with a functioning graft not as graft failure but as if they left the study, then the cumulative graft survival is 64.5% in the control group and 65.9% in the treated group. Thus, the mortality from infective causes and graft survival were not significantly different between the two groups. Hence, we draw the conclusion that use of HAHTG did not exert a beneficial effect on the ultimate outcome.
| 58,651
|
Progressive combined amyloid-elastic stain.
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A progressive staining technique is described that will permit demonstration of elastic structures and amyloid deposits in the same section. It is satisfactory for animal as well as human tissues, and for both pericollagen and perirecticulin types of amyloidosis.
| 58,656
|
[Change in lipid-protein interactions in the membranes of bacteria exposed to gramicidin S].
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Effect of cyclopeptide antibiotic gramicidin S on some enzymes and physical state of isolated Micrococcus lysodeikticus membranes is studied. Malate and lactate dehydrogenases were monotonously inhibited under the increase of gramicidin S concentration, while the activity of NADH-dehydrogenase firstly decreased and then reversed to the initial level under further increase of gramicidin S concentration. The oxygen uptake under oxidation of NADH and malate with membranes almost completely inhibited by the antibiotic, while the activity of ascorbate-TMPD-oxidase activity slightly inhibited by the same concentration of gramicidin. The addition of Triton X-100 completely eliminated the inhibitory effect of gramicidin on malate dehydrogenase. The introduction into the membrane of spine probes (2,2,6,6-tetramethyl-4-palmitoylamidopiperidine-1-oxile and 2(14-carboxytetradecyl)-2-ethyl-4,4-dimethyl-3-oxyazolidinyloxile) revealed that gramicidin caused the condensation of membrane lipid component. It is suggested that ionic interaction of gramicidin S with membrane phospholipids brings to "a freezing" of lipids which is a direct cause of impairing the activity of membrane respiration enzymes and the change of their position in the lipid matrix, thus inhibiting energy-producing processes in cell.
| 58,672
|
Use of the Brompton mixture in treating the chronic pain of malignant disease.
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Physical, psychological, financial, interpersonal and spiritual factors all modify the appreciation of chronic pain. The Brompton mixture is a highly effective, flexible, safe and convenient means of controlling the chronic pain of malignant disease. The mixture is a solution containing morphine; the dose of narcotic can be varied with the need for analgesia. It is given regularly, usually every 4 hours, with a phenothiazine, the main aims of therapy being prevention of pain rather than treatment, an unclouded sensorium and a normal affect.
| 58,709
|
Presence of blood group H antigen on a carcinoembryonic antigen, and its enzymatic modification into blood group A and B specificities.
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A carcinoembryonic antigen (CEA-M) was purified from a hepatic metastasis obtained from a blood group O patient with cancer of the rectum. Using 125I-labeled carcinoembryonic antigen (CEA) and blood group antisera, H specificity has been found on the CEA-M. As the addition of anti-H to anti-CEA does not modify the extent of binding of labeled CEA-M to its antibodies (86%), the H and CEA determinants are carried by the same molecule. The affinity chromatography of CEA-M on an immunosorbent "anti-H-Sepharose" demonstrated that a proportion of CEA-M molecules might bear both H and CEA antigenic determinants. In addition, glycosyltransferases were used to modify the blood group H specificity into blood group A or B specificities.
| 58,713
|
Precancerous changes in the stomach.
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Intestinal metaplasia is often associated with human gastric carcinoma. Intestinalization seems to be a typical example of abnormal differentiation and is possibly a precancerous state. For investigation of intestinal metaplasia, a method for visualizing disaccharidases using Tes-Tape was developed; this method was applied to many specimens of stomach surgically removed for the treatment of gastric carcinoma. More than 130 specimens of human stomach were investigated. Intestinalization was classified into types I and II intestinal metaplasia. In type I intestinal metaplasia, sucrase, maltase, trehalase, alkaline phosphatase, goblet cells, and Paneth cells were present; while the type II intestinal metaplasia, sucrase and maltase were present but alkaline phosphatase and trehalase were absent. In type II, goblet cells were present but not Paneth cells. The histochemical technique for sucrase was newly devised. Some of the villi with goblet cells in the area of intestinalization in the stomach were not stained by sucrase activity, although most of the villi were stained. The presence of a third type of metaplasia was suggested. Purified sucrases obtained from the intestine and one case of type I intestinal metaplasia showed blood group reactivity due to the oligosaccharide side chain. However, purified sucrases obtained from two cases of type II intestinal metaplasia were negative in blood group reactivity. A close relation between distribution of alpha-fetoprotein and carcinoembryonic antigen in gastric carcinoma and that in surrounding intestinal metaplasia is discussed.
| 58,722
|
Hyperthyroidism: diagnosis and treatment.
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The clinical diagnosis in cases of suspected hyperthyroidism is very valuable. Laboratory diagnosis rests largely on measurements of circulating thyroid hormones, with radio-iodine studies playing only a minor part. No one test is infallible and some understanding of basic physiological considerations is essential if serious errors are to be avoided. The choice of treatment plan is logically-based, but should take into account the quality of available services.
| 58,763
|
A glass-insulated "Elgiloy" microelectrode for recording unit activity in chronic monkey experiments.
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A glass-coated microelectrode made of a stiff cobalt--nickel alloy is described. The thickness of the glass coating and the length of the uninsulated tip can be varied as desired. The electrode is stiff enough to insert through the relatively tough dura of the monkey in chronic experiments. Further, the recording site can be marked by electrolytic deposition of iron and the Prussian blue reaction.
| 58,772
|
[The search for hematologic-immunological parameters with prognostic value in children with various tumors].
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In a total of 35 children affected with malignant sufferings (except leucaemias) the haematological-immunological parameters of children surviving for a short time are compared with those surviving for a long time. Compared with children surviving for a short time those surviving for long time had a more "normal" finding initially and during the control examination made after more than 5 years of a survival time which was free of complaints and recidives. The immunologically intact condition of the organism is assumed to be decisive for this course of disease.
| 58,813
|
Acid-fast properties and pyridine extraction of M. leprae.
|
The reportedly unique pyridine extractability of acid-fastness as an identifying characteristic for M. leprae was examined in the leprosy bacilli and in eight other strains of mycobacteria. The initial findings were, in general, in accord with previous reports except that M. smegmatis and M. phlei likewise demonstrated two hour pyridine extractability of acid-fastness. Perhaps, more significantly, it was found that this characteristic in M. leprae is related to aged, probably nonviable bacilli. Some other strains of mycobacteria when tested in aged cultures showed the same phenomenon while M. leprae cultivated in vitro in a recently developed medium resisted pyridine extraction up to three weeks of growth, but thereafter as the culture aged pyridine extractability became characteristic. It is concluded that this pyridine extractability of acid-fastness is a characteristic of aging or nonviable bacilli. As such it is not definitive in the determination of whether or not in vitro cultivation of M. leprae has been achieved.
| 58,845
|
Glycoproteins of Sendai virus: purification and antigenic analysis.
|
Solubilized envelope antigens (glycoproteins) of Sendai virus were purified in a DEAE-Bio-Gel A column. Monospecific antisera were prepared against the antigens, designated HN and F glycoproteins. These glycoproteins are antigenically distinct. Immunodiffusion analyses of the envelope antigens of three representative paramyxoviruses (Sendai, Yucaipa, and Newcastle disease virus)did not reveal any cross-reactions among them with antisera specific for Sendai virus glycoproteins.
| 58,850
|
Lipoprotein from the outer membrane of Escherichia coli: purification, paracrystallization, and some properties of its free form.
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In the envelope of Escherichia coli, is a lipoprotein of molecular weight 7,200 as a major envelope protein. This lipoprotein was previously shown to exist in two different forms in the outer membrane of E. coli: the free form and the boundform, which is covalently linked to the peptidoglycau. The free form of the lipoprotein has been purified and paracrystallized by adding acetone to a sodium dodecyl sulfate solution in the presence of magnesium ion. The paracrystals were needle shaped. An electron micrograph of the negatively stained paracrystals showed a highly ordered ultrastructure. The chemical structure of the free form was compared with that of the bound form by (i) the amino acid composition, (ii) the fatty acid composition, and (iii) the peptide analysis after cyanogen bromide cleavage. The alpha-helical content of the free form of the lipoprotein was measured from the circular dichroism spectrum of the lipoprotein in 0.01% sodium dodecyl sulfate and found to be 87%. Using the purified lipoprotein as antigen, antiserum against the free form of the lipoprotein was obtained. Immunoprecipitation of the lipoprotein with the antiserum was found to be very specific, since only the free form of the lipoprotein was found as a major peak when the antiserum was reacted with the whole envelope proteins solubilized in 0.2% sodium dodecyl sulfate, and the immunoprecipitate thus formed was analyzed by polyacrylamide gel electrophoresis.
| 58,861
|
Importance of full size complementary DNA in nucleic acid hybridization.
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The size of the DNA product synthesized by RNA-directed DNA polymerase (isolated from avian myeloblastosis virus) was found to be important for complementary DNA (cDNA)-mRNA hybridization reactions. Incomplete cDNA to rabbit reticulocyte globin mRNA formed poor hybrids and presumably lacked sequences needed for hybridization. The size of the cDNA synthesized was influenced by the reaction conditions used. The complementary DNA product contained 10 S material when synthesis was done at high deoxynucleoside triphosphate concentrations (greater than 50 muM) while the product was smaller than the template when synthesis was at lower concentrations. The concentration and size (oligo(dT)6 to (dT)10) of primer had little or no effect on the product size. Increasing the concentration of 10 S globin mRNA caused the cDNA product to contain more small material. The cDNA synthesized at high deoxynucleoside triphosphate concentrations was fractionated into heavy, medium, and light fractions by alkaline sucrose density centrifugation. All hybridized to globin mRNA. The larger cDNAs had a higher TM when hybridized to globin mRNA, a lower dTMP/dCMP ratio (indicating that the poly(dT) region constituted a smaller fraction of the molecule), and gave increased protection of 125I-labeled mRNA from nuclease digestion. The full size cDNA was especially useful for studying the RNA transcribed from chromatin by RNA polymerase. The complement of the 5' end of the mRNA is contained only in full size cDNA; the 5' end is the part of the mRNA first transcribed by the RNA polymerase assuming correct transcription. Thus, full size cDNA can hybridize more effectively to the short RNA transcripts that are obtained than partial cDNA. RNA transcribed from rabbit bone marrow chromatin by Escherichia coli RNA polymerase hybridized twice as efficiently to complete cDNA as it did to partial cDNA demonstrating the usefulness of full size cDNA.
| 58,864
|
The effects of glutaraldehyde treatment and horesradish peroxidase conjugation on the immunoreactivity of bovine myelin encephalitogenic protein.
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The effects of the immunoreactivity of bovine myelin encephalitogenic protein (EP) of treatment with glutaraldehyde and conjugation with horeradish peroxidase (HRP) were investigated by complement fixation and immunohistochemistry. Both glutaraldehyde treatment and HRP conjugation of EP decreased but did not abolish the reactivity of EP with rabbit anti-EP. Conjugation of EP to HRP by the two-step method of Avrameas had less detrimental effects on the immunochemical reactivity of EP than did the one-step procecure. The use of EP-HRP conjugates to probe for antibodies to EP is an immunochemically sound system with the major limitation that the number of antibody-producing cells is likely to be underestimated due to the failure to detect cells producing low levels of antibody or antibodies directed toward determinants altered by the modification procedures.
| 58,926
|
Quantitative studies of Gm allotypes. I. Reappraisal of the method using an autoanalyzer.
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In this study, various parameters for the autoanalyzer hemagglutination-inhibition circuit applied to Gm studies, were examined. Details are given of modifications of this circiut and related methodology, that improve its precision and the reproducibility of results: use of a cells counter, effects of temperature, PVP, Tween 20, anti-Gm concentration, etc. The effects of age, storage and freezing on quantitative Gm allotypes antigenicity are also stressed.
| 58,943
|
High density lipoprotein (HDL) polymorphisms in rabbit. III. Quantitative determination of HDL and the inherited Hl 1 and R 67 antigens.
|
Immunological quantification of HDL and the inherited antigens Hl 1 and R 67 was performed on serum samples from two rabbit populations (Dutch and Albino) comprising a total of 106 animals. The female animals were found to have a higher concentration of both antigens and of HDL than the male animals. The amounts of antigens and of HDL were not obviously normally distributed, but appeared to be more bimodally distributed. The relationship between the amount of antigens and amount of HDL were tested for each animal. A significant positive correlation was found between the amount of R 67 antigen and HDL both for male and female animals in the Albino rabbit population, and for male animals in the Dutch rabbit population. A significant correlation was also found between amounts of Hl 1 and R 67 antigens in the Dutch rabbit population.
| 58,950
|
Streptococcal M protein extracted by nonionic detergent. I. Properties of the antiphagocytic and type-specific molecules.
|
Group A streptococcal M protein was extracted with nonionic detergent and subjected to a number of physical, chemical, and immunological tests. M protein thus extracted was composed of multiple protein bands, ranging from 35,000 down to 6,000 daltons, all having type-specific precipitating activity. The anti-phagocytic proteins, however, were limited to three molecular species having mol wt of 28,000, 31,000, and 35,000 daltons, and could be separated from those proteins that had only type specificity. Physical studies indicated that these proteins existed as individual asymmetrical molecules which were not aggregated. By radiolabeling M protein on living streptococci, it was determined that these protein bands were found on the streptococcal cell wall in this multiple form. Also, by pulse chase experiments supported by chemical and immunological data, evidence was obtained strongly suggesting that the smaller, type-specific molecules are used to assemble the larger, antiphagocytic proteins.
| 58,958
|
Electron microscopy of tobacco mosaic virus prepared with the aid of negative staining-carbon film techniques.
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The negative staining-carbon technique has been applied to suspensions of freshly prepared type strain tobacco mosaic virus particles in high concentrations. Electron microscope images show that paracrystalline arrays of the virus were formed, in which large areas of rods could be viewed along their long axes and in parallel arrays in horizontal positions. High-resolution micrographs showed the protein structure units in rods photographed in both vertical and horizontal orientations.
| 58,964
|
Protein synthesis in zinc deficient rats during tularemia.
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The effect of zinc deficiency on protein synthesis in rats during tularemia was studied. Five weeks prior to infection with the live vaccine strain of Francisella tularensis, rats had been assigned to one of three dietary groups: zinc deficient (-Zn), pair-fed (PF) or ad libitum (AL). Within 4 weeks, zinc deficiency manifested itself by diminished growth rate, decreased serum and liver zinc concentrations and alopecia. By 18 hour post infection, rats of all groups were febrile and exhibited an increased hepatic uptake of zinc. Despite initially lower concentrations of seromucoid in the PF and -Zn groups, infection elicited an increase in seromucoid concentration as well as enhanced incorporation of 3H-leucine into this fraction of comparable degree in all dietary groups. The same held true for ceruloplasmin. Alpha 2-macrofetoprotein also increased to the same extent in all dietary groups. Infection was associated with a decrease in extractable albumin in ad libitum and pair fed control groups. Only the -Zn group showed a significant decrease in specific activity suggestive of diminished albumin synthesis. Zinc deficiency of itself did not cause a decrement in radiolabel in muscle protein. Thus, despite documented zinc deficiency, rats subjected to the stress of infection respond by synthesizing increased amounts of acute phase globulins apparently at the expense of serum albumin and muscle protein synthesis.
| 58,980
|
Pigment containing lipid vesicles. I. Preparation and characterization of chlorophyll a-lecithin vesicles.
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Vesicles obtained by sonication of chlorophyll a-lecithin mixtures dispersed in anaqueous medium closely resemble the well-characterized vesicles similarly prepared from pure lipids. They are bounded by one spherical lipid bilayer which contains the chlorophyll a. Appropriate conditions for sonication prevent substantial degradation of the membrane constituents. Up to one chlorophyll a molecule per 55 lecithins can be incorporated into membranes. The average Stokes' radius of the vesicles determined by analytical sieve chromatography is 102 +/- 5 A and independent of the chloropyll a content. The membrane is visible in the electron-microscope when the vesicles are treated with osmium tetroxide prior to negative staining. The osmium fixation is, however, not strong enough to allow for a preparation of the vesicles for thin sectioning (dehydration, embedding in epoxide).
| 58,996
|
Plasma-urate measurements in predicting fetal death in hypertensive pregnancy.
|
The relation of perinatal mortality to plasma-urate concentrations and blood-pressure was studied in 332 pregnant patients with hypertension. Perinatal mortality was markedly increased when maternal plasma-urate concentrations were raised, generally in association with severe pre-eclampsia of early onset. Plasma-urate was a better indicator than blood-pressure of prognosis for the fetus. Maternal hypertension, even severe, without hyperuricaemia, was associated with an excellent prognosis for the fetus. Conversely, when maternal hypertension was mild and hyperuricaemia was severe, the prognosis for the fetus was poor. These findings suggest that, in terms of fetal health, changes in renal handling of urate may be a more important feature of pre-eclampsia than the hypertension.
| 59,013
|
Is lactase the receptor and uncoating enzyme for infantile enteritis (rota) viruses?
|
Rotaviruses are now regarded as important causes of diarrhoea in man, cattle, pigs, mice, and possibly other animals. Characteristically, disease occurs in newborn and young animals, and infection seems limited to the differentiated gut epithelial cells. The major surface polypeptide of the calf scours rotavirus is glycosylated, and highly purified beta-galactosidase (lactase) interacts with the virus in vitro causing removal of the outer shell of the capsid (uncoating). It is suggested that lactase present in the brush border of the intestinal epithelial cell performs a similar function in vivo by acting as a combined receptor and uncoating enzyme for the rotavirus. This hypothesis is consistent with the observations that rotaviruses seem to infect only gut epithelial cells, and that infant animals, whose lactase concentrations are generally higher than those of adult animals, seem more susceptible to rotavirus infections. Implications of the hypothesis include possible new approaches to laboratory cultivation of rotaviruses, which should be more successful in cells selected for surface lactase activity, and the suggestion that the epidemiology of human rotavirus infections may be influenced by the fact that different ethnic groups have different lactase levels (and hence lactose intolerance) in adulthood.
| 59,021
|
Von Willebrand disease San Diego, a new variant.
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A reduced level of factor XII has been observed in 9 of 39 patients with von Willebrand's disease. This apparent common variant of von Willebrand's disease has not previously been described, and its significance is not known.
| 59,075
|
Effect of beta-adrenergic blockade on plasma-renin activity and intractable hypertension in patients receiving regular dialysis treatment.
|
The effect of propranolol has been studied in two patients with chronic renal failure and hypertension which remained refractory despite the removal of excess sodium and water by dialysis. Measurements of plasma-renin, exchangeable sodium, and blood-volume demonstrated that in both patients hypertension was due to excess renin. The administration of propranolol was followed by a rapid fall in blood-pressure to normal, thereby obviating the need for bilateral nephrectomy. In both patients the fall in blood-pressure was accompanied by a striking fall in plasma-renin, and in one there was a highly significant association between plasma-renin activity and mean arterial pressure.
| 59,151
|
Cysteamine, methionine, and penicillamine in the treatment of paracetamol poisoning.
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60 patients with paracetamol poisoning have been treated with intravenous cysteamine, L-methionine, or D-penicillamine and the incidence and severity of hepatic necrosis compared with those observed in 70 patients receiving supportive therapy only. Of 31 patients with 4-hour plasma-paracetamol concentrations greater than 250 mug/ml given supportive therapy 22 sustained severe liver damage, 3 died in hepatic failure, and 4 developed acute renal failure. None of 23 similarly poisoned patients given cysteamine within 10 hours of ingestion suffered severe liver damage or renal failure and none died. Cysteamine was partially effective at 10-12 hours, but ineffective 12 hours or more after ingestion. Liver damage was absent or mild in 17 patients given L-methionine within 10-12 hours of ingestion but severe in 3 treated within 10 hours. Of 5 patients treated with D-penicillamine, 1 developed severe liver damage with acute renal failure. It is concluded that cysteamine prevents severe liver damage after paracetamol poisoning if given within 10 hours in adequate dosage.
| 59,181
|
Electron microscopic studies of viral agents in Crohn's disease.
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Viral agents isolated from ileal filtrates of patients with Crohn's disease have been successfully cultivated in continuous rabbit ileum tissue-culture and grown to titres sufficient to allow electron microscopic characterisation. Electron microscopic studies showed clusters of viral particles only in tissue-cultures inoculated with cultivated viruses originally obtained from tissues from patients with Crohn's disease. Control cultures showed no evidence of viral agents. The mean virus-particle diameter was 30 nm. An electron-dense central core was present and a spiculated coat was demonstrated. The physical chemical properties of this agent, as previously described, together with the electron microscopic appearance are consistent with the appearance of a picornavirus.
| 59,238
|
Swine influenza virus and the recycling of influenza-A viruses in man.
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Sera collected in 1967 and 1972 from people in the 0-100 age-group showed haemagglutination-inhibition (H.I.) antibody to swine virus A/Iowa/15/30 (Hsw1N1) in greatest number and with highest titre in people born before 1918. A slight decrease was observed from 1967 to 1972 in the number of sera with antibody to swine virus and in the height of the titres. The recently isolated A/New Jersey/10/76 (Hsw1N1) virus showed a result comparable to that of the Swine/1930 virus in sera of 1972. On the analogy of the findings in 1968, when the Hong Kong virus became epidemic in human populations and antibody to this virus was found in sera of people over 70 years, the suggestion is made that the recurrence of swine virus as an epidemic agent of human influenza may be expected around 1986. Fourfold or greater increase of antibody to Swine/1930 virus was observed in about 4--5% of people infected by or immunised with H3N2 viruses. This response occurred in people who had been in touch with the epidemic influenza-A viruses Hsw1N1, H0N1, and H1N1 during the swine era of 1918 to 1956. Following immunisation with H3N2 viruses of persons showing no response to H3N2 viruses in their serum 5% did show a fourfold or greater heterotypic H.I. antibody rise to swine virus. This finding is of consequence for the diagnostic serology of influenza.
| 59,252
|
Alpha-fetoprotein in the serum of patients with neoplasms of the gastrointestinal tract.
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Serum alpha-fetoprotein was estimated in 61 patients with neoplasms of the gastrointestinal tract, 29 healthy controls and 10 pregnant women. Almost half ot the patients had increased values of alpha-fetoprotein and no parellelism between alpha-fetoprotein and liver metastasis was found. Decreasing of the alpha-fetoprotein during the postoperative period could be considered a sign for a total removal of the tumor, and, on the contrary -- increasing of alpha-fetoprotein -- for a recurrence.
| 59,318
|
Protein histochemistry methods for colloid identification to metastases of thyroid carcinoma.
|
Evidence for a thyroid origin of tumorous metastases may be facilitated by a histochemical determination of colloid. It is supported by the presence of proteins, demonstrable especially by the reaction for tyrosine, and a simultaneous absence, or only traces of acid mucosubstances. Contrary to existing literary reports, an intraplasmatic formation of mucin has been detected in certain thyroid carcinomas and their metastases. The most difficult to diferentiate histochemically from thyroid colloid is the secrete of certain adenocarcinomas of the prostate.
| 59,319
|
Origin of amniotic fluid alpha-fetoprotein in normal and defective pregnancies.
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Alpha-fetoprotein was determined by electroimmunodiffusion and radioimmunoassay in 109 neonatal urine samples and 94 amniotic fluid samples. The samples were obtained from newborns and from pregnancies ranging in gestational age from 20 to 40 weeks. When alpha-fetoprotein values of neonatal urine and amniotic fluid were correspondingly correlated with gestational age, almost identical declining curves could be drawn. Twenty-one cerebrospinal fluid samples from newborns ranging from 25 to 40 weeks of gestation were similarly determined. No correlation between cerebrospinal fluid alpha-fetoprotein and gestational age could be demonstrated. It is concluded that fetal urine is the major source of alpha-fetoprotein in the amniotic fluid of normal pregnancy. In pregnancies associated with neural tube defects, alpha-fetoprotein elevation is probably not due to the leakage of cerebrospinal fluid into the amniotic cavity.
| 59,326
|
Combination chemothereapy with cis-diamminedichloroplatinum (II) and bleomycin in tumors of the head and neck.
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28 patients with head and neck tumors not suitable for definitive treatment with radiation or surgery were treated with cis-diamminedichloroplatinum (II) and bleomycin in combination. Of 24 adequately treated patients, there were 3 partial remissions lasting for 3,3 and 6 months, respectively. Toxicity of the regimen as given was substantial; 13 patients showed some evidence of nephrotoxicity and there were 2 drug deaths related to progressive renal failure. 1 patient developed bleomycin pulmonary toxicity.
| 59,332
|
Gastrointestinal changes in patients with hypogammaglobulinemia.
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Three cases of hypogammaglobulinemia are described. In all cases the first symptoms of disease manifesting as pneumonia were preceded by diarrhea. In gastric biopsy there was atrophic gastritis with lack of plasmocytes. All patients demonstrated gastric achylia and symptoms of malabsorption syndrome. The causes of gastrointestinal changes, most probably infections, with simultaneous defective mucosal barrier are discussed.
| 59,351
|
Prostatic tissue cell growth and assessment.
|
The potential for use of cell and organ culture systems in the study of prostatic tumors is high. The nature of this organ and our lack of basic information about it limit the usefulness of in vitro techniques at present but these shortcomings can be overcome by concerted effort of interested investigators. At the present time organ culture methods are available which can yield valuable information. To achieve notable success requires considerable understanding of the method in terms of principles, detail of technique, and interpretation. Several important questions must be resolved in order for cell culture methods to achieve their potential: (1) effect of disaggregation procedures on prostatic tissue, (2) appropriate selection of specimens, particularly with regard to controls, (3) ability to clearly identify and select cell types, and (4) how to overcome the variable of serum as a source of hormones. Considering the fact that less work has been done on the prostate than most tissues, recent developments in the area of cell and organ culture seem most encouraging and the future looks bright indeed. Two continuously propagated cell lines of pupative prostatic origin have been described. One of these developed in culture apparently as the result of a spontaneous transformation while the other was propagated from an adenocarcinoma. If these cell lines can be conclusively proved to be representative of the tissues of origin we already are well on the way to the application of in vitro systems to study of the prostate.
| 59,386
|
Alien cancers of the duodenum.
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Invasion of the duodenum by contiguous cancer or an isolated metastasis can manifest itself with the signs and symptoms of primary cancer of the duodenum. Fourteen patients were identified with this type of diagnostic confusion. All of their tumors were in the second or third portion of the duodenum. Although the median length of survival after excision of the tumor or palliative bypass operations in these patients was nine months, considerably longer survival times have also been described. Barium enema examinations and excretory urograms should be considered as diagnostic tests for any patient with a tumor of the duodenum to identify the contiguous carcinomas of the colon and kidney subject to long palliation.
| 59,394
|
Cell mediated lympholysis in man. The impact of HLA-C antigens.
|
From a population of individuals, all HLA-A, B, and C tissue typed in relation to the Sixth International Histocompatibility Workshop, an experimental investigation has been performed to study the influence of the HLA-Cwl, w2, w3, w4, and w5 antigens in the Cell Mediated Lympholysis (CML) test. The average cytolysis obtained due to allogenic attack of one HLA-C antigen equals 12.6%, but like the HLA-A and B antigens, HLA-C antigens exhibit differences with regard to sensitizing and target potential. This indicates either a heterogeneity of these antigens or the existence of separate CML determinants. It is concluded that the HLA-C antigens may account for the cytolysis observed in some of the combinations exhibiting cytolysis which cannot be explained by the HLA-A and B antigens.
| 59,406
|
Hydroxyethyl lactamide, a dye solvent useful in vital staining.
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In a search for new vital stains to reveal the microanatomy of nudibranch mollusks, the slow or very low solubility of many dyes in sea water posed a serious problem. Preliminary dissolution in tap water proved impractical. Hydroxyethyl lactamide, an odorless liquid and dye solvent was found ideal since it permits immediate attainment of saturated solutions of dyes in sea water. Since hydroxyethyl lactamide passed the severe "eolid nudibranch test" and has been found nonirritating for the very sensitive rhinophorial structures, and furthermore since it has been used by the pharmaceutical industry as a vehicle in antibiotic preparations, it appears to be an ideal universal dye solvent for general use in vital staining. It has been used extensively in unpublished research by the writer on vital staining of nudibranchs. It has a low order of physiological activity and can be regarded an essentially inert when used in vital staining.
| 59,418
|
Improved microradiographic contrast for bone stain-historadiography.
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Microradiographs of 5-micron sections of methyl methacrylate embedded undemineralized bone show poor resolution, but prestaining with silver nitrate increases the radioopacity of the calcified tissues to soft x-rays without masking regional differences in microscopic mineralization. Identical results are achieved using aqueous (pH 5.8 and 7.5) or ammoniacal solutions (pH 7.9). Atomic absorption spectrometry detected no loss of calcium from the sections during staining. Osteoid in plastic-embedded bone is not rendered radiopaque by this technique even after prolonged staining times (5 min-2 hr).
| 59,423
|
Further evidence of heterogeneity within the Kidd blood group system.
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Serological studies on blood of selected individuals show that red blood cells from individuals genetically JkaJk and JkbJk give single dose agglutination reactions with anti-Jka and anti-Jkb respectively, but react as strongly with anti-JkaJkb as do cells from random individuals. A Jk(a+b-) Oriental person has been found whose red blood cells give a single dose reaction with anti-Jka, but react more weakly than do cells from random people in tests with anti-JkaJkb. The results support a conclusion that the antigen recognized by anti-JkaJkb is a distinct and separate antigen of the Kidd blood group system.
| 59,434
|
[Improvement of parenteral feeding through the additional administration of a serum protein solution].
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On 7 days - 5 postoperative - patients undergoing Billroth I or Billroth II were continuously infused apparatively witn an amino acid mixture of 100% and a glucose-xylitol-solution of 25% (group I). One group (group II) additionally received a serum protein solution. From the first preoperative day to the fifth day of the postoperative period we determined individual parameters in blood and urine. A decrease of serum phosphate level beginning on the first day after starting parenteral nutrition was observed. In the nitrogen balances, in total protein and albumin concentration there were no differences, but serum gamma-globulin concentration of group II was very low at the end of the parenteral nutrition period, a point which at present cannot be explained.
| 59,474
|
[Comparative studies on influences of physical and psychological strain on the ECG in coronary disease patients].
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In 7 patients suffering from heart infarction the electrocardiogram was telemetrically registered during telecast of the world championship in football 1974. The same patients were tested on a bicycle ergometer with standardized loads of 50, 75, 100 and 125 Watt for 3 minutes. Heart rate under psychial strain did not exceed the rate of 50 Watt on bicycle ergometer. Only 1 patient showed some extrasystoles during ergometry. Looking at television all patients developed extrasystoles, in one case 122. If the FRG took part in the game, ventricular extrasystoles were two times, auricular extrasystoles were four times more frequent than during games between foreign countries. It is concluded that psychical strain is able to produce dangerous arrhythmias in patients suffering from coronary heart disease. This danger cannot be proved by bicycle ergometry.
| 59,480
|
Assessment of the mid systolic click late systolic murmur syndrome by noninvasive methods.
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In patients with the mid systolic click/late systolic murmur syndrome (MSC/LSM Sy) a ballooning, billowing or aneurysmal protrusion of one or both mitral leaflets has previously been described in angiographic studies. It is accepted that besides angiography noninvasive methods such as dynamic electrocardiography, phonocardiography, apexcardiography and echocardiography can provide valuable information in the diagnosis of this syndrome. Little is known however about diagnostic value and sensitivity of these methods. The dynamic Ecg, recorded during an average of 10 hours, showed in 8/20 patients (40%) one or several significant arrhythmias such as frequent ventricular premature contractions (VPCs) (greater than 12/min), multifocal VPCs, VPCs in a row or ventricular tachycardia, or 2 degrees SA-block. 12/20 patients (60%) showed in the phonocardiogram a movement of the click toward the first heart sound when the patients' position was changed from supine to sitting. In 40% of the patients a double or triple click was recorded. A late systolic bulge in the apexcardiogram was seen in 13/20 patients (65%). In one patient the recording was not successful. Echocardiographic signs of abnormal posterior movement (prolapse) of one or both mitral leaflets were recorded in 15/20 patients (75%). Five echocardiograms did not show any abnormality, but all these cases demonstrated in their apexcardiogram a late systolic bulge. We believe that in patients with the MSC/LSM Sy a mitral valve abnormality can be documented adequately by noninvasive methods.
| 59,481
|
[Variable stainability of Purkinje cells].
|
The author refers about different staining of the Purkinje-cells with luxol-fast-blue, gallocyanin, thionin and toluidin blue, chrom-alum-hematoxylin-phloxin, impregnation according to Palmgren, lithium and iron-hematoxylin, combination of the staining with phloxin and the Palmgren-impregnation and about the different activity on the acid phosphatase. The phenomenon that in the same histological specimen the positive (dark, chromophile) and negative (light, chromophobe) cells are situated beside, is true for normal animals too, but the number of the dark Purkinje cells is conspicuous higher after stress situations (96-h. immobilisation, intermittent hypoxia). This finding interprets the author by the occurence of phospholipids by binding on the granulated endoplasmatic reticulum, but also as a property of the neuroplasm. The author emphasizes that the staining dualism "light -- dark" of the ganglion cells does not refer only to the ganglion cells of the spinal ganglions (et on some epithelial cells), but also on the Purkinje cells.
| 59,483
|
Histogenesis of mucin in follicular mucinosis. An electron microscopic study.
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Many dilated cystic ergastoplasms, including their granular, filamentous contents, the developed Golgi apparatuses, and vesicles were observed in the cytoplasm of affected root sheath cells, which were accompanied by much amorphous agglutination of fine granular or flocculent materials in the interstices. These extracellular substances were stained with ruthenium red and seemed to correspond to increased metachromatic materials, probably composed of hyaluronic acid. Possible structures for hyaluronic acid were discussed. Mucin in follicular mucinosis seemed to be produced by secretory function of follicle cells.
| 59,502
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Apoptosis in lichen planus and several other dermatoses. Intra-epidermal cell death with filamentous degeneration.
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In hyperplastic conditions of the skin, eosinophilic bodies are often observed in the epidermis and upper dermis. These have been named variously Civatte body of lichen planus and dyskeratotic cell of actinic keratosis. In the present studies, it was found that (i) these cells commonly contain whorls of distinct filaments (60-80 A), which may be attached to desmosomes; (ii) unlike keratinized cells, the cellular envelope was not thickened by the formation of the marginal band; (iii) the cytoplasm contains a large number of vacuoles; (iv) the nucleus is lost by condensation or diffuse disintegration; and (v) these cells could be dropped into the upper dermis and filamentous contents could be released to dermal phagocytes. From these observations it was concluded that Civatte bodies and other eosinophilic bodies of neoplastic and hyperplastic epidermis represent "filamentous degeneration" or premature keratinization of keratinocytes.
| 59,504
|
Molecular order of carbohydrate components in cell walls of bacteria, fungi and algae according to the topo-optical reaction of the vicinal OH groups.
|
Selective topo-optical staining of vicinal OH groups with aldehyde-bisulphite-toluidine blue (ABT) has been used for studying the molecular structural order of polysaccharide components in microbial cell walls and capsules. (i) By intensive metachromatic staining in the light microscope, the method demonstrates carbohydrates, containing free vicinal OH or acylaminohydroxyl groups. (ii) The birefringence induced by oriented toluidine blue binding of the ABT reaction, provides information about the linear order of the reacting carbohydrate chains, a possibility not offered by other ultrastructural methods. Furthermore the different optical character of birefringence induced by ABT is indicative of the presence of (a) tangentially oriented polysaccharide chains in the cell wall of the molds and bacterial capsules; or (b) radially oriented OH groups suggesting helical glycan chains of peptidoglucomannane and mucopeptide in the yeasts and bacterial cell walls.
| 59,521
|
The effect of rhizobiophages on the effectiveness of Rhizobium meliloti in symbiosis with lucerne. I. Effect of various strains of R. meliloti and rhizobiophages on the yield and nitrogen fixation in lucerne.
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Pot and test-tube experiments were carried out on the effect of phages on yield and nitrogen fixation in lucerne inoculated with effective and non-effective strains of Rhizobium meliloti. It was found that some strains of R. meliloti became activated by the phages, which was reflected in an increase in yield and in crude protein content in the plants, while others lost their effectiveness. The results of pot experiments were in line with those of the test-tube experiments and have demonstrated that the effect of phages on the effectiveness of Rhizobium is not simply negative or positive, but depends on the properties of the bacterial strains used.
| 59,525
|
Studies of blood clotting system during anaesthesia for prostatectomy. I. Epidural analgesia.
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The studies were carried out on 20 patients operated on for prostatic adenoma under epidural analgesia. It was observed that activation of the fibrinolytic system is due to trauma to the prostate and is connected with release of plasmin activators into circulating blood. Epidural analgesia has no effect on the blood clotting and fibrinolysis systems and is a safe method in prostatectomy.
| 59,555
|
Surgical management of carcinoma of the junction of the main hepatic ducts.
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Twenty-six patients are reviewed who had primary carcinomas involving the junction of the hepatic ducts. The majority had had an initial procedure of palliative biliary diversion elsewhere and were referred for further treatment. In three cases, en bloc resection of the tumor with total hepatectomy and orthotopic liver transplantation were performed. All tumor growth was encompassed in each case, but within 4 months all succumbed as a result of allograft rejection. Auxiliary (heterotopic) liver transplantation was performed in another patient because of recurrent disease after previous left hepatic resection in continuity with a hilar duct lesion. Five patients underwent hepatic lobectomy with en bloc resection of the hepatic duct junction. When adequate tumor excision was not feasible, biliary diversion could provide good palliation in some instances for extended periods of time. This is demonstrated by one patient who lived for 4 years and 4 months after the initial operation. In the meantime, the patient underwent 6 subsequent procedures of dilating of constricted bile ducts and tube cannulation of the biliary tree. Biliary diversion was achieved in 4 cases by intrahepatic cholangiojejunostomy. One of these patients, who is on chemotherapy, is asymptomatic one year after surgery.
| 59,580
|
Creatine phosphokinase levels in children with severe developmental disturbances.
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Serum creatine phosphokinase (CPK) levels were studied in individuals: 40 psychotic children suffering from childhood autism, atypical personality development, and childhood schizophrenia; five children with childhood aphasia; 22 children with severe personality disorders; 29 normal children and normal siblings of psychotic children; and 14 normal parents of psychotic children. Creatine phosphokinase levels from the entire population of adults and children were normally disturbed, and the mean CPK levels for the eight diagnostic groups were within normal limits. Those 22 children with personality disorders had significantly higher CPK levels than the other diagnostic groups. This relatively higher level of CPK may be related to vulnerability to later development of schizophrenic spectrum disorders. There was no apparent relationship between CPK levels and motor activity, nor was there any change in the level of CPK during a trial of psychoactive medication. Creatine phosphokinase levels remained relatively stable on test-retest determination.
| 59,582
|
HLA typing.
|
I present an overview of HLA typing, a method of evaluating donor-recipient compatibility. The major histocompatibility system in man, the HLA region, considered to control the immunologic response to transplantation and perhaps to certain diseases, is discussed in relation to chromosomal location, chromosomal mapping, association with other markers, nomenclature of the gene products (the HLA antigens), inheritance of the HLA antigens, and methods of determining these antigens. Use of HLA typing is currently most applicable in the correlation of certain diseases with HLA antigen frequency, in evaluating donor-recipient pairs for renal and bone marrow transplantation and for transfusion of platelets and granulocytes and in paternity testing.
| 59,584
|
Inhibition of denaturation of human gamma globulin by a mixture of L-histidine, L-cystine, and copper, and its clinical implication in rheumatoid arthritis.
|
A mixture of histidine, cystine, and copper mimicked gold thiomalate, N-ethylmaleimide, and p-chloro-mercuribenzoic acid in inhibiting sulfhydryl-disulfide interchange-mediated denaturation of human gamma globulin, bovine serum albumin, and diluted human serum. Measurable inhibitory effects were obtained with a mixture of physiologic concentrations of L-histidine, L-cystine, and copper. This work suggests a mechanism by which the hypohistidinemia of rheumatoid arthritis could contribute to the pathogenesis of the disease.
| 59,600
|
A kinetic study of the inhibition of human and bovine trypsins and chymotrypsins by the inter-alpha-inhibitor from human plasma.
|
Human plasma inter-alpha-inhibitor forms 1:1 inactive complexes with human and bovine trypsins (EC 3.4.21.4) and chymotrypsins (EC 3.4.21.1). The association and dissociation rate constants as well as the equilibrium dissociation constants (Ki) of the complexes formed of inter-alpha-inhibitor and the four proteases have been measured. The most stable complexes are those formed with the bovine enzymes. For instance, Ki = 2.1-10-11 M for bovine trypsin whereas Ki = 1.2 - 10-8 M for human trypsin. Whatever the species, the complexes formed with the chymotrypsins are less stable than those formed with the trypsins.
| 59,607
|
[Study of the complex between porcine plasmin and alpha2-macroglobulin (author's transl)].
|
Porcine plasmin (EC 3.4.21.7) is obtained from plasminogen activated by human urokinase. This enzyme can bind, in an equimolecular ratio, to an alpha2-macroglobulin isolated from porcine serum. The number of active sites of plasmin has been determined through a burst titration of nitroaniline during the presteady-state hydrolysis of an amide substrate (N-alpha-carbobenzoxy-L-arginine-p-nitroanilide). The kinetic constants relative to a very sensitive ester substrate (N-alpha-carbobenzoxy-L-lysine nitrophenylester) hydrolysis have been measured. The binding of plasmin to alpha2-macroglobulin results in a complete inhibition of proteolytic activity, a reduction of active sites number and a decrease of esterolytic activity towards this substrate. In the complex, the residual activity (about 60%) is protected from protein inhibitors. Absorbance difference spectra show that 1 mol of alpha2-macroglobulin binds 1 mol of plasmin and 2 mol of trypsin. When plasmin is first bound to alpha2-macroglobulin, only 1 mol of trypsin can gain access tothe second site without removing the plasmin, showing that a steric hindrance is implicated in the inhibition performed by alpha2-macroglobulin binding.
| 59,608
|
Membrane characteristics of established human T- and B-cell lines. Cross-reactivity of human T-antigenic determinants with peripheral lymphocytes of non-human primates and the presence of MLC antigens on cultured T-cell lines.
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Human T-cell lines (MOLT-4 and SOMMER-T) were injected into rabbits and monkeys (stumptail and squirrel monkeys). Rabbit anti-MOLT serum was absorbed with human liver and cultured B cells. Absorbed anti-MOLT serum was cytotoxic to lymphocytes of baboons and stumptail monkeys. Rabbit anti-MOLT and SOMMER-T sera after absorption with liver and B cell showed florescent ring formation in baboon and stumptail lymphocytes by using immunoflurescence techniques. On the other hand, antisera against MOLT and SOMMER-T cells in stumptail and squirrel monkeys were not only cytotoxic to MOLT and SOMMER-T cells, but also to other T-cell lines, CCRF-CEM and CCRF-HSB-2 cells. Cultured B-cell lines stimulated allogeneic and xenogeneic (rabbit and monkeys) lymphocytes far better than cultured T-cells lines did. T-cell lines, CCRF-HSB-2 and SOMMER-T (number 8402), gave small but significant stimulation to allogenic lymphocytes especially in the presence of foetal calf serum. MOLT-4B failed to stimulatie allogeneic lymphocytes. When lymphocytes of non-human primates and rabbit were cultured with human B- and T-cell lines in the presence of foetal calf serum, CCRF-HSB-2 and SOMMER-T cells stimulated xenogeneic lymphocytes of rabbit, squirrel monkey and stumptail monkey. MOLT-4 cells stimulated lymphocytes of baboon to some extent. These results indicate that although cultured B-cell lines had more mixed lyphocyte reaction (MLR) stimulating structure than T-cell lines, the latter still maintained some stimulating structure on the membrances.
| 59,650
|
Determinant competition during the immune response to N-acyl derivatives of ox insulin in the Hartley guinea-pig.
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Subgroups of female Hartley guinea-pigs were immunized with N-carbamylated ox insulin, N-maleylated ox insulin, N-phthaloylated ox insulin, or with the crystalline ox insulin from which the N-acylated insulins had been prepared. The immunogens were administered in water-in-oil emulsions containing pertussis vaccine as adjuvant. Sera obtained 20 days after secondary immunization were assayed for their antibody titres to iodo-ox insulin and their insulin-binding capacities. The data were log transformed for statistical comparison. N-carbamylated ox insulin seemed to be as immunogenic as crystalline ox insulin and no specific carbamyl hapten antibody could be found. N-maleylated and N-phthaloylated ox insulins yelded significantly less antibody cross-reactingwith iodo-ox insulin, but produced a complementary quantity of specific maleyl and phthaloyl hapten antibody respectively. Thus it was shown that in the system used the immune response was partitioned between different determinants, ox insulin and its N-acylated derivatives being equipotent immunogens.
| 59,652
|
Serum alpha1-fetoprotein in cystic fibrosis.
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In 38 children and adolescents with cystic fibrosis, in 19 normal children and 62 healthy adults the serum alpha1-fetoprotein concentrations were measured by radioimmunoassay. In cystic fibrosis patients 97.5% and in normal children 95% of the alpha1-fetoprotein values were within the normal range for healthy adults (1--9 ng/ml). Critical judgement of the reported findings in literature and our own results demonstrate that the investigation of alpha1-fetoprotein in the serum cannot serve for detecting homozygotes of cystic fibrosis genes or heterozygote carriers.
| 59,665
|
Immunological investigations of antigenicity and specificity of soluble collagen fractions. IV. Anaphylaxis and allergy experiments.
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Collagen prepared from rat, calf, or pig skin was tested on guinea pigs for active cutaneous anaphylaxis. Only one fraction of calf skin collagen gave a slight, positive reaction. No positive reactions were observed in 21 subjects submitted to patch tests and 12 subjects submitted to scratch tests with pig skin collagen. Therefore preparations of pig skin collagen may be used for wound treatment without any risk.
| 59,667
|
Immunity after infections with Myxoviruses.
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Influenza, parainfluenza and respiratory syncytial viruses cause respiratory infections in man with consequent transient and sometimes imperfect against reinfection. Humoral immunity and probably cell-mediated immunity contribute to resistance. Whereas circulating antibodies are more important for influenza viruses, secretory antibody are relatively speaking more important for parainfluenza and respiratory syncytial virsues. Measles and mumps induced longlasting immunity which can be correlated with circulating neutralizing antibodies. Certain immune responses against measles and respiratory syncytial virus cause pathological reactions after infection with the same virus.
| 59,707
|
Somatic cell hybrids between human lymphoma lines. II. Spontaneous and induced patterns of the Epstein-Barr virus (EBV) cycle.
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The regulation of spontaneous, IUDR-induced and P3HR-1 virus-induced EA and VCA production patterns was studied in two new somatic hybrids between human lymphoma lines. The hybrid 8A was derived from the crossing of the non-producer Raji with the spontaneous producer Daudi line. The second hybrid, 83, was produced by the fusion of Raji with the EBV-genome-negative B-lymphoma line, BJAB. The studies suggest the following EBV regulation patterns: (1) the spontaneous production of EA and VCA appears to be regulated by controls that differ from the regulators of P3HR-1 virus-induced or IUDR-induced EA synthesis. While spontaneous producer status was dominant over non-producer status, the level of EA inducibility was set by one of the parental cells, Raji ATG, and could either raise (in the previously studied Raji/Namalwa hybrid, cf Nyormoi et al. 1973) or depress (in Raji/Daudi) the level of relative EA inducibility found in the partner cell. (2) Although EA production is a prerequisite for VCA synthesis, the latter is under its own restriction mechanisms, quite independent of those that regulate the level of EA synthesis. (3) Inducibility of EA synthesis by P3HR-1 virus and by IUDR appear to be under the influence of at least partially identical controls. (4) EBV-negative lymphoma cells, exemplified by BJAB, may exert a "complementation" effect on the EA inducibility of their EBV-positive fusion partner, in spite of their own restrictivity against virus-induced EA synthesis. In more general terms, it is obvious that the EBV cycle is under the influence of multiple regulatory mechanisms in the human lymphoid cell. Depending on the parental cell and viral genomes that are allowed to interact, somatic cell hybrids may display a variety of patterns. At this time, cell hybridization is one of the few pathways that permit an approach to this complex and completely unknown world.
| 59,708
|
Further characterization of phosphatase activities using non-specific substrates.
|
The demonstration of non-lysosomal acid phosphatase has been the subject of a number of recent investigations. In the present study we compared the enzyme activities in rat liver and kidney that are revealed after incubation in the presence of either beta-glycerophosphate, p-nitrophenylphosphate or phenylphosphate at varying pH. As seen by others, the activity towards p-nitrophenylphosphate at pH 5-6 was confined to lysosomes, Golgi apparatus, endoplasmic reticulum (ER), nuclear envelope and plasmalemma. The reactivity of the plasmalemma and the ER was increased at pH 7. The TER of Küpffer cells in the liver stained intensely in contrast to the ER of the parenchymal cells, which stained only weakly. In the presence of NaF, all sites except the plasmalemma became negative. Addition of a levamisole-analogue, L-p-bromotetramisole, which is a specific inhibitor of alkaline phosphatase, resulted in the disappearance of the plasmalemmal activity whereas the activity at the other sites appeared unaltered. The rather unusual locations of activities with so-called non-specific substrates were further compared with those obtained with specific substrates such as glucose-6-phosphate and thiamine pyrophospate. The possible implication of these data in relation to the specificity of marker-enzymes for subcellular organelles is discussed.
| 59,721
|
IgA and IgG anti-ragweed antibodies in nasal secretions. Quantitative measurements of antibodies and correlation with inhibition of histamine release.
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Total secretory IgA and specific anti-antigen E (AgE) antibodies (ab) in the IgA and IgG classes were measured in concentrated nasal washings from ragweed allergic and normal individuals by antigen binding or anti-alpha-radioimmunoassays. Virtually all the allergic patients had significant IgA (45/49) and IgG (46/49) ab to AgE in their nasal washings. By contrast, washings from most normal persons contained no measurable IgA (13/15) ab or IgG (13/15) ab to AgE. The total IgA levels in allergic washings were not significantly different from those in normal washings and they were used to standardize the ab measurements. Parenteral immunotherapy with ragweed extract increased specific nasal IgA ab from 10.6 +/- 2.7 (SEM) to 39.0 +/- 8.7 ng AgE bound/mg IgA and IgG ab from 17.2 +/- 2.6 to 65.1 +/- 7.4 ng AgE bound/mg IgA (P less than 0.001 for both classes). The ratio of IgA:IgG ab was not affected by therapy, and for treated patients, there was no correlation (rs + 0.32, P greater than 0.1) between nasal IgG ab and serum IgG ab. These results suggest that at least part of the nasal IgG ab is produced locally. Blocking activity in the nasal washings was measured by inhibition of histamine release and was found to correlate directly (rs + 0.85, P less than 0.001) with binding activity for AgE. Some washings from normal persons caused slight inhibition of histamine release but others caused enhancement. Nasal washings were fractionated by passage over Sephadex G-200. Inhibition of histamine release by dilutions of the IgA-rich and IgG-rich fractions correlated well with binding activity in these fractions. None of these results support the hypothesis that allergic individuals are deficient in secretory IgA or secretory ab responses. These results, however, are in keeping with the theory that hay fever occurs in a high-responder population which is genetically able to respond to low doses of inhalant antigens.
| 59,737
|
Rosette formation between human lymphocytes and sheep erythrocytes. Inhibition of rosette formation by specific glycopeptides.
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Rosette formation with unsensitized sheep erythrocytes is a characteristic of human thymus dependent lymphocytes. Release of glycopeptides from the sheep erythrocyte by trypsin reduces rosette formation. These tryptic glycopeptides inhibit rosette formation by untrypsinized sheep erythrocytes; this suggests that rosetting is mediated by erythrocyte surface glycopeptides. To investigate the molecular nature of this interaction, we examined the abilities of various model compounds to act as haptenic inhibitors of rosette formation. Inhibition is given by glycopeptides bearing oligosaccharide units rich in sialic acid, galactose, N-acetylglucosamine, and mannose linked to asparagine residues through glycosylamine bonds. Among compounds tested, fetuin glycopeptide is most effective, but human transferrin glycopeptide and human erythrocyte glycopeptide I also inhibit rosette formation. Other compounds including human erythrocyte glycopeptide II, human IgG glycopeptide, lacto-N-neotetraose, 3'- and 6'-sialyllactose show no significant inhibition. Neither sialic acid, galactose, manose, nor N-acetyl-glucosamine alone inhibits rosette formation. Stepwise degradation of fetuin glycopeptide established the galactose residues as important determinants of inhibitory activity. Fetuin glycopeptide blocks rosette formation when added to a suspension of human lymphocytes and sheep erythrocytes or when preincubated with human lymphocytes, but not when preincubated with sheep erythrocytes. Studies of the binding of [3H] fetuin glycopeptide to normal lymphocytes demonstrate 7.5 x 10(6) saturable binding sites per cell. No saturable binding of this compound to sheep erythrocyte membranes is observed. Compared to normals, lymphocytes from patients with chronic lymphatic leukemia demonstrate decreased fetuin glycopeptide binding with a mean of 0.9 x 10(6) sites per cell. This decreased binding correlates with the impaired ability of these cells to form rosettes. The data suggest that fetuin glycopeptide inhibits rosette formation by binding to the thymus-dependent cell where competition occurs with sheep erythrocytes for specific lymphocyte surface receptors.
| 59,739
|
X-ray microanalysis of zinc and calcium in ultrathin sections of human sperm cells using the pyroantimonate technique.
|
X-ray microanalysis of pyroantimonate-fixed sperm cells indicates the retention of calcium and zinc subcellularly in similar proportions to air dried cells. The ultrastructure is well preserved and is corelated with the analysis. Sodium, potassium and chlorine are all removed during the fixation. CAlcium and zinc are found present intracellularly both in association with and independent of antimonate precipitation. There thus appears to be a varying degree of binding of those elements subcellularly, precipitation occurring where binding is reduced.
| 59,774
|
Histamine release by chemotactic, formyl methionine-containing peptides.
|
Certain formyl dipeptides and tripeptides containing methionine released histamine from human basophils at concentrations of 10(-4) to 10(-7) M. However, N-formyl amino acids did not release histamine. Tripeptides, in general, were more active than dipeptides. An acyl group was required for histamine release although an N-terminal position for Met was not essential. Histamine release from human basophils by these peptides correlated well with their chemotactic activity for rabbit leukocytes.
| 59,783
|
Humoral immune responses in Rana catesbiana frogs and tadpoles.
|
Rana catesbiana adult frogs and tadpoles were immunized with the bacteriophage F2, 0X-174, and T4 and the haptens 2,4 dinitrophenyl (DNP) and fluorescein (FTC). The haptens were conjugated with bovine serum albumin (BSA), bovine gamma globulin (BGG), or horsehoe crab hemocyanin (Hycn). Sera were obtained from immunized animals at invervals up to six months after immunization. The antibody activities were measured by bacteriophage neutralization techniques. Sucrose density gradients were used to separate the antibody classes. Both adults and tadpoles responded to each of the antigens tested. High molecular weight antibodies were predominant in both groups of animals. Low molecular weight antibody activity was not found in adults until nine weeks post immunization but, thereafter, this fraction increased throughout the immune response. Low molecular weight antibodies could also be identified in serum of tadpoles, but only under certain conditions.
| 59,790
|
Measurement of diphenylhydantoin and phenobarbital by enzyme immunoassay and gas-liquid chromatography.
|
A new enzyme-multiplied immunoassay technique (EMIT) was compared with Kupferberg's gas-liquid chromatography (GLC) for the determination of diphenylhydantoin and phenobarbital. 116 plasma samples of patients with epilepsy were examined simultaneously by EMIT and GLC. The precision of repeated determinations was similar for both procedures. There was good agreement between the EMIT and GLC results. The rapid and precise analysis, made possible by the EMIT system, is useful for the treatment of epilepsies.
| 59,797
|
The fatty acid composition of major glycosphingolipids (cerebrosides and sulfatides) in human cerebral white matter measured by a simple micromethod.
|
A micromethod for the investigation of the fatty acid composition of myelin glycosphingolipids (cerebrosides and sulfatides) suitable for general application in the investigation of neurological disorders, especially demyelinating diseases, is presented. Using the lipids extracted from 1 g of material these are freed of phospholipids by Florisil column chromatography and separated by thin-layer chromatography into 2 cerebroside and sulfatide fractions which are analyzed individually. The results obtained from the white matter of 13 normal adult brains are distributed within a narrow range which is most pronounced for the group of long chain fatty acids. Our results also agree with those quoted from literature.
| 59,798
|
Interaction of human Waldenström's IgM proteins with guinea pig and human complement.
|
The activity of purified human Waldenström's IgM protein to fix complement of human and guinea pig origins was compared at different temperatures using the polystyrene latex particle-adsorption method. It was shown that the interaction of the IgM proteins with complement differed depending on the source of complement and that a pronounced heterogeneity in complement-fixing activity was observed among the IgM proteins when tested with guinea pig complement. Thus, by the use of guinea pig complement, six human IgM proteins examined were classified roughly into two groups, one having a high and the other a low activity at 3 C as well as at 37 degrees C. With human complement, five proteins showed a rather uniform activity at 37 degrees C. However, there was one protein with no detectable activity, suggesting the presence of non-complement-fixing protein in the IgM class. All the six proteins showed no significant activity with human complement at 3 C. No antigenic difference has been found as yet in the Fc or Cmu2 region among these IgM proteins examined.
| 59,830
|
Persistent gastrointestinal bleeding due to angiodysplasia of the gut in von Willebrand's disease.
|
Gastronintestinal vascular dysplasia as a cause of persistently recurring melaena is reported in two patients with von Willebrand's disease. Colonic wall vasculature was affected in one patient, the abnormality being demonstrated both radiologically and at operative hemicolectomy undertaken to control bleeding. Abnormalities in the vasculature of the duodenal and jejunal walls were found in the second patient at operation and necropsy, though not demonstrated by angiography.
| 59,851
|
"Self": standard of comparison for immunological recognition of foreignness.
|
It is suggested that the markers of biological individuality--i.e. the HLA antigens--may serve as the standard profiles against which foreignness is directly compared.
| 59,859
|
Appraising current therapy for breast cancer. 2. Irradiation.
|
The best combination of methods for managing primary breast cancer may not yet be known. Radiation therapy has been proved effective in decreasing the incidence of local and regional recurrence following mastectomy. Thus, until a superior regimen is established, I recommend local and regional irradiation for patients at high risk for recurrence. Local irradiation is also an effective means of achieving palliation of symptoms associated with metastatic disease.
| 59,923
|
Euflavine: effect on brain heavy metal content and staining pattern, and on shuttle box behavior in goldfish.
|
Goldfish were exposed to euflavine in doses of 7-100 mg/l for 1h-14 days. The treatment resulted in a reduced stainability of the brain with the Timm histochemical procedure for "heavy metals". In contrast, analysis by flameless atomic absorption spectrophotometry showed no significant changes in the concentrations of zinc and of copper after euflavine treatment. In the shuttle box a significant increase in general activity was found. These results, compared to earlier work with other chelating agents, indicate that such drugs do not have a uniform effect on behavior, and that they do not cause a true depletion of heavy metals in the brain.
| 59,934
|
Radiotherapy of metastases of mammary carcinoma.
|
Radiotherapy is a very successful way of treating localized metastatic or recurrent breast cancer. The success of treatment depends largely on the site of the metastasis and the dose applied. It is not a substitute for systemic treatment, but superior in the treatment of localized disease.
| 59,936
|
HLA antigen (A & B loci) frequency in Addisonian pernicious anaemia.
|
Sixty-six patients with Addisonian pernicious anaemia have been HLA typed and compared with 86 controls of the same ethnic group. No deviation in antigen frequency was found to be specific for the disease group as a whole. The most significant deviation found was an increased frequency of HLA-B8 in those patients with coincident thyroid autoantibodies. Pernicious anaemia seems to be the exception to the demonstrated association between HLA-B8 and the organ specific autoimmune diseases studied up to the present time.
| 59,964
|
[Blood group specific properties of leucocyte nuclei (author's transl)].
|
The absorbing and precipitating capacity of leucocyte nuclear suspensions derived from conserved blood of various blood groups was examined with anti-A-, anti-B-, anti-H, anti-M-, anti-N-, and anti-CDE-, and anti-D-sera as well as with anti-AHP- and Evonymus-extracts. Nuclei of blood group A absorbed anti-A, but not anti-B; nuclei of blood group B absorbed anti-B, but not anti-A. Nuclei of blood group 0 absorbed anti-H, but neither anti-A nor anti-B. Anti-M-, anti-N-, anti-CDE-, and anti-D-sera showed no absorption effect after incubation with leucocyte nuclei of corresponding blood groups. A nuclei were strongly precipitated by anti-AHP; B- and 0-nuclei were markedly precipitated by Evonymus-extract. B- and 0-nuclei showed only a weak precipitation with anti-AHP-extract; A-nuclei were only slightly precipitated by Evonymus-extract. Hence, leucocyte nuclei possess blood group specific properties, which, according to the present studies, are limited to certain blood group systems.
| 60,008
|
[The concentration of antibodies to several exoenzymes of beta-hemolytic streptococci in commercial preparations of gamma globulin].
|
For the purpose of possible use of commercial preparations of homologous gamma-globulin in the outbreaks of streptococcus affections the authors studied the content of antibodies to some streptococcus antigens, namely to O-streptolysin, streptohyaluronidase and streptokinase. High antibody titres to streptokinase were observed in 62.7, to O-streptolysin--in 35.2 and to streptohyaluronidase--in 15.4% of the batches under study. The greatest amount of antibodies to all the antigens under study was revealed in gamma-globulin prepared from the blood sera collected during the automno-winter period of the year.
| 60,017
|
[The effect of D-penicillamine on experimental allergic arthritis in rabbits].
|
The effect of D-penicillamine on experimental allergic arthritis in rabbits (16 with arthritis and 15 controls) was investigated. After 40 days of treatment with D-penicillamine (intravenous) the arthritis had receded to a large extent. At the same time a maturation inhibition of the hematopoietic marrow had occurred in all the treated arthritic and control animals. The results suggest that D-penicillamine affects fast proliferating cells, to which the precursors of immunologically active cells in the synovial membrane also belong.
| 60,013
|
Intestinal absorption of L-tryptophan in scleroderma.
|
The purpose of this investigation was to study the intestinal absorption of L-tryptophan and to assess the absorptive function of the intestine in scleroderma. The oral L-tryptophan loading test was performed in 31 cases of systemic scleroderma (progressive systemic sclerosis, PSS) and 3 cases of localized scleroderma. Serum levels of tryptophan and urinary excretion of indole-acetic acid (IAA) and indican (IS) were determined in order to assess intestinal absorption of tryptophan. In 10 cases the D-xylose test and in 4 cases Schilling's test was also performed. Furthermore, in vitro binding of L-tryptophan by plasma proteins in PSS and in other skin diseases as controls was studied. The normal increase in serum tryptophan after loading was noted in 17 cases (in 14 cases of PSS with a mild, slow progression in 3 cases of PSS with a severe, rapidly progressing course). In 10 of these cases, urinary excretion of IAA was higher than normal and in normal and in 3 cases excretion of urinary IS was also above normal. On the other hand, in 14 cases of severe, rapidly progressing PSS and in 2 of 3 cases of widespread linear scleroderma, serum levels of tryptophan were markedly depressed after loading, while urinary excretion of IAA and IS was normal. In all 4 cases studied, Schilling's test was normal, and only in 2 of 10 cases of PSS was the D-xylose test abnormal. It is concluded that in the majority of cases of PSS, intestinal absorpiton of tryptophan is normal as also is the absorptive function of the intestine. The slight rise in serum tryptophan after loading in some cases of PSS may be a result of increased binding of tryptophan by albumin.
| 60,020
|
Tricuspid atresia: results of treatment in 160 children.
|
Experience in managing 160 patients with tricuspid atresia is reviewed. The majority of these children require operative treatment in the 1st year of life. Clinical management of this rather complex anomaly is simplified by classifying each child according to total pulmonary blood flow. An overall plan of management for patients with decreased pulmonary flow is suggested. This consists of a Potts shunt as an initial procedure, limiting its anastomotic growth so that pulmonary flow becomes inadequate at age 10 to 12 years. A Glenn anastomosis is then constructed as the second procedue. The Fontan procedure should be considered carefully as an alternative to the Glenn anastomosis in these older children. Children with increased pulmonary blood flow and transposition of the great arteries are likely to require pulmonary arterial banding in infancy. Otherwise, patients in this smaller group are managed with the same overall plan. Results of long-term palliation have been good.
| 60,052
|
Improved staining method for differentiating immature germ cells from white blood cells in human seminal fluid.
|
A new staining method for differentiating WBCs from immature germ cells in seminal fluid has been studied. It is a combination of Bryan's sperm stain, which particulary stains the acrosomal cap of the spermatozoa and the spermatid, and Leishman's blood stain which stains the WBCs in the same way as found in blood smears. The peroxidase positive granules in the cytoplasm of the PMN leukocytes are seen clearly. Thus, it is possible to differentiate PMN leukocytes from non-separated spermatids when they are present in a common cytoplasm. The staining of acrosomal cap permits differentiation between spermatids and lymphocytes.
| 60,068
|
Primary carcinoma of the liver.
|
Primary carcinoma of the liver is rare in Western countries but it is a common malignant tumour in many parts of the tropics. Much has been learnt in recent years about its pathology, manifestations, and aetiology that is relevant to the whole field of oncology. The important distinction between carcinomas of liver-cell and bile-duct origin, the phenomenon of alpha-fetoprotein production, and the role of cirrhosis are discussed in the context of newly discovered aetiological factors such as gonadal steroids, mycotoxins, and the hepatitis B virus.
| 60,075
|
A colour reaction for the differentiation of ascomycetous and hemibasidiomycetous yeasts.
|
Seventy yeast strains, representative of twenty-six ascogenous genera, four saprobic hemibasidiomycetous genera and thirteen genera of the Cryptococcales were tested for their reaction with the stabilized aromatic diazonium compound, Diazonium Blue B salt. An aqueous, buffered solution of this compound gave a characteristic red colouration with the colonies of the hemibasidiomycetous species and those Cryptococcales characterized by the hemibasidiomycetous cell-wall type. The characteristic colour reaction was not observed with colonies of either the ascomycetous yeasts or those Cryptococcales characterized by the ascomycetous cell-wall type. The possibly taxonomic use of the colour reaction with Diazonium Blue B salt as an affinitive characteristic is discussed.
| 60,081
|
Attempts to identify viruses in rheumatoid synovial cells.
|
Synovial fibroblast cell strains derived from the synovial membranes of 7 patients with rheumatoid arthritis were examined for the presence of viruses, in particular leucoviruses. Seven similar synovial strains derived from patients with other arthritic conditions were used as a control group. Evidence of the presence of a virus or a viral genome was looked for by several methods of induction followed by 3H-uridine labelling of the cultures. In addition, the culture supernatant, after induction and after the synovial strains had been co-cultivated with a variety of cell lines from several species, was assayed for the presence of viral RNA-dependent DNA polymerase activity. The DNA-polymerase activity of the synovial cells themselves was also determined. No evidence was found by any of these techniques to indicate the presence of virus or viral information within the synovial fibroblasts.
| 60,087
|
Influence of the adrenal glucocorticoids on the stimulation of synthesis of hepatic ribonucleic acid and plasma acute-phase globulins by leucocytic endogenous mediator.
|
An injection of unpurified leucocytice endogenous mediator into rats results in an increased incorporation of [6(-14)C]orotate into hepatic RNA, an increase in the concentration of RNA associated with the bound ribosomal fraction of liver, and increases in the concentrations in serum of acute-phase proteins such as alpha2-macrofoetoprotein and haptoglobin. If given 3 days after adrenalectomy or 7 days after hypophysectomy,, leucocyte factor did not induce the increase in RNA synthesis or alpha2-macrofoetoprotein concentrations but did stimulate an increase in serum haptoglobin. When hypophysectomized or adrenalectomized rats received daily subcutaneous injections of 0.5mg of cortisol, leucocyte factor again induced a significant increase in the synthesis of hepatic RNA and an increase in the concentration of serum alpha2-macrofoetoprotein. These observations suggest that leucocyte factor can regulate acute-phase-protein synthesis at several different sites, one or more of which requires permissive action of the glucocorticoid hormones. Futher, leucocyte factor will stimulate an increase rate of incorporation of orotate into hepatic ribosomes when added in vitro in the presence of cortisol to a liver-perfusion system. Thus the stimulatory effect of leucocyte factor may be directy on liver but may require the presence of other hormones to stimulate the incorporation of orotate into RNA.
| 60,101
|
Observations on the pyridoxal 5'-phosphate inhibition of DNA polymerases.
|
Pyridoxal 5'-phosphate at concentrations greater than 0.5 mM inhibits polymerization of deoxynucleoside triphosphate catalyzed by a variety of DNA polymerases. The requirement for a phosphate as well as aldehyde moiety of pyridoxal phosphate for inhibition to occur is clearly shown by the fact that neither pyridoxal nor pyridoxamine phosphate are effective inhibitors. Since the addition of nonenzyme protein or increasing the amount of template primer exerted no protective effect, there appears to be specific affinity between pyridoxal phosphate and polymerase protein. The deoxynucleoside triphosphates, however, could reverse the inhibition. The binding of pyridoxal 5'-phosphate to enzyme appears to be mediated through classical Schiff base formation between the pyridoxal phosphate and the free amino group(s) present at the active site of the polymerase protein. Kinetic studies indicate that inhibition by pyridoxal phosphate is competitive with respect to substrate deoxynucleoside triphosphate(s).
| 60,130
|
Alpha-foetoprotein and oestrogen metabolism. I. -Influence of alpha-foetoprotein on the metabolism of steroids by rat liver microsomes in vitro.
|
Rat alpha-foetoprotein (AFP) was shown to inhibit the formation of water soluble metabolities of oestrone and oestradiol by incubation with microsomes from rat liver in the presence of NADPH. The results support the proposal that in young animals the low activity of enzymes responsible of oestradiol metabolism may be due in part to the presence of AFP and not only to the low level of these enzymes.
| 60,142
|
Mesangial cell dysfunction detected by accumulation of aggregated protein in rats with streptozotocin induced diabetes.
|
Diminished renal glomerular mesangial phagocytic function has been found in rats with streptozotocin induced diabetes. Similar impairment was produced by high dose cortisone and growth hormone, whereas oestrogen had a stimulant effect. The findings could be relevant to the understanding of human diabetic nephropathy.
| 60,145
|
The subcellular localization of calcium in vertebrate smooth muscle; calcium-containing and calcium-accumulating structures in muscle cells of mouse intestine.
|
The intracellular localization of calcium by means of cytochemical techniques was studied in smooth muscle cells of mouse intestine. When the lead acetate method according to Carasso and Favard (1966) was used calcium was found in mitochondria and sarcoplasmic reticulum and occasionally between the myofilaments. The active ATP-dependent accumulation of calcium into cell structures was investigated by the oxalate method (Heumann and Zebe, 1967). After appropriate treatment the only structures of smooth muscle cells which contained calcium oxalate (identified by microprobe analysis) were elements of the sarcoplasmic reticulum. The results are discussed in relation to the role of calcium in the control of muscle activity during the contraction-relaxation cycle.
| 60,177
|
Enzymatic in vitro synthesis of globin genes.
|
Full-length, single-stranded rabbit globin cDNA, synthesized by AMV reverse transcriptase, apparently contains a small double-stranded sequence (hairpin) at the 3' terminus. This cDNA can serve as template-primer for E. coli DNA polymerase I, which synthesizes a strand complementary to the cDNA and covalently bound to it. The loop connecting the two strands can be cut by S1 nuclease. Reassociation, hybridization, and restriction endonuclease studies, as well as electrophoretic analyses, indicate that the sequential actions of reverse transcriptase, DNA polymerase 1, and S1 nuclease generate full-length, double-stranded synthetic globin genes.
| 60,178
|
[Morphological findings in the liver tissue of Australia antigen carriers].
|
In twenty-four blood-donors were performed, after the average period of seventy-four days following the evidence of HB Ag in blood, the punction biopsies of the hepatic tissue. In microscopical examination one finding corresponded with the picture of a moderate, chronically persisting hepatitis, and in the twenty-first sample we found non-characteristic alterations, especially in the form of matrix activation of Kupffer's cells and isolated, dispersing resorption histiocytary nodules. Demonstrated in ten blood-donors was HB Ag in the plasma of hepatocytes.
| 60,181
|
Hepatitis-B: a review.
|
The recent literature on various aspects of hepatitis-B is reviewed with emphasis on the interrelationships of viral structure, antigenic components, and host immune response in acute, chronic, and asymptomatic carrier states of the infection. The mode of replication and mechanisms of transmission are discussed. Special attention is paid to potential non-parenteral routes of spread. The role of hepatitis-B in associated immune complex diseases and in hepatoma is outlined. A guide to the interpretation of serologic tests for hepatitis-B associated antigen and antibody patterns is presented in relation to the clinical stage and prognosis of the infection. Therapy, except in conceptual terms, is not covered but a summary of the current status of active and passive immunization is given. The unresolved question of the infectivity of carrier medical staff for their patient contacts, and the reverse, is discussed.
| 60,200
|
Contingent negative variation and the distraction--arousal hypothesis.
|
Thirty-two normal volunteers were tested in three conditions: (1) a constant-foreperiod reaction-time situation consisting of a flash--tone--key-press sequence (control condition); (2) the addition of a short-term memory task consisting of four letters presented within the flash--tone interval with the requirement that they be repeated after key-press to tone (letters--recall); (3) the presentation of letters without short-term memory (letters--no recall). The task involving short-term memory of letters produced a significant reduction in amplitude of CNV for central (Cz) and parietal (Pz) recording sites. The association of CNV decrease and lengthened reaction time to tone was interpreted as a CNV distraction effect. The accompaniment of this distraction effect by elevated heart rate levels and increased frequency of eyeblinks was considered a distraction--arousal association and an important source of disruption in CNV development. These results were interpreted as support for the distraction--arousal hypothesis and appear to provide a sensitive complex of four measures for the evaluation of psychological processes, including the assessment of psychotropic drug effects. Eyeblink frequency in particular appears to be a sensitive indicator of distraction--arousal processes and a potentially useful measure of disturbed psychological functioning. The finding in control conditions of lower CNV amplitude in frontal than in central and posterior recording sites was viewed as a distraction effect due to efforts at eye movement control. The possibility was raised that frontal areas of the brain mediate sustained (tonic) distraction effects whereas centro-parietal regions mediate phasic distraction effects, at least when produced by stimuli of a lexical nature.
| 60,215
|
Human sleep and 5-HTP. Effects of repeated high doses and of association with benserazide (RO.04.4602).
|
On account of the conflicting data concerning the action of 5-HTP on human sleep, repeated high doses were administered to three healthy subjects. The paradoxical sleep time and percentage tend to show a decrease during the 2nd week of treatment, followed by a rebound effect after the end of the treatment. In two subjects who initially had a small amount of slow wave sleep (SWS), the treatment induced an increase in SWS that persisted after the end of the treatment. Similar results were obtained after administration of 5-HTP together with RO.04.4602.
| 60,227
|
Paromomycin and dihydrostreptomycin binding to Escherichia coli ribosomes.
|
Paromomycin binds specifically to a single type of binding site on the 70-S streptomycin-sensitive Escherichia coli ribosome. This site is different from that of dihydrostreptomycin since paromomycin binds to streptomycin-resistant ribosomes and sine dihydrostreptomycin does not compete for paromomycin binding. Paromomycin binding, unlike dihydrostreptomycin binding, is independent of changes in ribosome concentration but influenced by magnesium ion concentration. Moreover, paromomycin does not bind to the 30-S subunit of the streptomycin-sensitive ribosome, except in the presence of dihydrostreptomycin, which probably induces the conformational changes necessary for a paromomycin binding site. This induction does not occur with streptomycin-resistant ribosomes. Neither antibiotic binds to the 50-S subunit. In general, binding of the one antibiotic increases the number of sites available for binding of the other. Both antibiotics exhibit marked non-specific binding at high antibiotic/ribosome ratios. Competition studies have enabled the classification of other aminoglycosides according to their ability to compete for the paromomycin and dihydrostreptomycin binding sites. Derivatives structurally related to paromomycin compete for its binding, the degree of competition being related to antibacterial activity, but do not compete for dihydrostreptomycin binding; they, on the contrary, increase the number of dihydrostreptomycin binding sites. Neither gentamicin nor kanamycin derivatives, which induce a high level of misreading, nor kasugamycin and spectinomycin, which do not induce misreading, compete for paromomycin or dihydrostreptomycin binding sites. Other sites may be involved in the binding of these aminoglycosides and in inducing misreading.
| 60,235
|
[Identification of simian chromosomes by the differential staining method with Romanovskii-Giemza stain. II. Papio hamadryas].
|
By means of differential staining with the Romanovsky - Gimsa dye the distribution of G-bands was studied in chromosomes of bone marrow cells and of cultured peripheral blood lymphocytes in Papio hamadryas. All the homologous chromosome pairs were identified. It was shown, as compared Papio hamadryas karyotypes with that of Macaca mulatta, that patterns of most chromosomes differentiation were similar. Certain differences between these species were observed in the character of differentiation of chromosomes 1 and 5 and also in parameters of chromosomes 2 and 21 (X).
| 60,271
|
The dynamics and location of axonal transport blockade by acute intraocular pressure elevation in primate optic nerve.
|
Axonal transport in primate optic nerve axons was studied by autoradiography, scintillation counting, and electron microscopy under conditions of short-term intraocular pressure elevation. With elevation of intraocular pressure to 30 mm. Hg below mean arterial blood pressure, blockage of transport was detected within 2 hours by autoradiography and within 1 hour by electron microscopy. The earliest buildup of radioactively labeled protein and ultrastructurally visible cellular organelles was within the scleral lamina cribrosa. The degree of blockage, judged by amount of label buildup, increased with time. Some transported material traversed the lamina cribrosa despite pressure elevation at the level tested. Reversal of transport blockade occurred rapidly after normalization of intraocular pressure.
| 60,300
|
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