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antimicrobial activity of quaternary ammonium salts of some saturated heterocycloalkyl amines [1].antimicrobial activity of n-alkyl-n-dodecylpiperidinium bromides and n-ethyl-n-dodecylheterocycloalkyl ammonium bromides (pyrrolidine, morpholine, perhydroazepine) determined on grampositive and gramnegative bacteria, yeasts and moulds, presented as minimum inhibition concentration (mic). comparison of the effect of change of structure: lengthening of alkyl chain, change of heterocyclic ring. change in the length of alkyl chain markedly affects the antimicrobial activity, change of heterocyclic ...1979157009
idiotype-related cellular events during the anamnestic immune response to salmonella typhi in rabbits.himalayan rabbits of a closed colony were immunized with injections of heat-killed salmonella typhi and antiidiotypic antibodies against the induced anti- s. typhi antibodies were produced in rabbits of the same colony as well as in random-bred rabbits. rabbits of the closed colony showed no proliferative response in a mixed lymphocyte culture of peripheral blood. antiidiotypic sera from himalayan rabbits recognized the idiotype in the corresponding immunizing sera alone, while one of sera from ...1979157100
[differential diagnosis of back pain--a rare case of spondylitis]. 1979157636
intestinal and serum antibody responses in mice after oral immunization with salmonella, escherichia coli, and salmonella-escherichia coli hybrid strains.after oral feeding of mice with avirulent salmonella, escherichia coli, or hybrid strains, only certain bacterial strains were able to multiply and persist within the small intestinal peyer's patches. after oral vaccination alone, or oral priming and subsequent parenteral boosting, antibody class and titers were detected, using a radioimmunoassay on serum and intestinal fluid or a plaque-forming cell assay on spleens. only those strains that persisted in the peyer's patches stimulated the produc ...1979157980
[epidemiologic relationships between frequency of salmonellae in surface waters and sewage and incidence of human salmonellosis in hamburg (1969--1978) (author's transl)]. 1979158154
[prevention of pullorum disease-fowl typhus in poultry]. 1979158252
activity of the escherichia coli reca-gene product. 1979158477
modelling of the small-angle x-ray diffraction arising from the surface lattices of phages lambda and p22. 1979158660
[systematic control of infectious diseases in slesvig holstein (author's transl)]. 1979158720
correlation between the toxicity of platinum drugs to l1210 leukaemia cells and their mutagenic properties. 1979159050
[salmonella in various types of meat products]. 1979159063
[epidemic of salmonelloses in the south moravian region (author's transl)]. 1979159132
[isolation of salmonellae from humans in the south moravian region during the 15-year period (1962--1976) (author's transl)]. 1979159134
short-term tests for carcinogens and mutagens. 1979159413
bacterial lipopolysaccharide activates suppressor b lymphocytes.lipopolysaccharide (lps) extracted from the outer cell wall of gram-negative bacteria modulates the immune response in vivo and in vitro. depending on the experimental conditions, it may enhance or inhibit the production of humoral antibody. the pathway by which lps suppresses antibody production is examined in this study. c57bl/6 spleen cells incubated with lps (greater than 10 micrograms/ml) not only fail to produce antibody to sheep erythrocytes in vitro but also, when transferred 24 hr after ...1979159461
tumor induction in swiss mice by filtrable agent and salmonella typhimurium.combined inoculation of a cell-free extract of leukotic tissue of d103 mice and salmonella typhimurium into adult swiss mice induced leukosis and solid tumors. the induced solid tumors were histologically multifarious, and were transplantable in swiss mice, but not in other strains of mice.1979160187
response to a metal ion-citrate complex in bacterial sensing.salmonella typhimurium responds chemotactically to gradients of divalent cations in the presence of citrate ions. the actual chemoeffector is the citrate-metal ion complex, which acts as an attractant. citrate (which is also a chemoeffector for salmonella) and the citrate-metal ion complex are recognized by different receptors. the response of salmonells, which can transport citrate through its membrane, is quite different than that of escherichia coli, which cannot.1979160411
gene for the rna polymerase sigma subunit mapped in salmonella typhimurium and escherichia coli by cloning and deletion.the genes for the rna polymerase sigma subunit (rpod) and dna primase (dnag) of salmonella typhimurium have been cloned into lambda vectors. combined restriction, deletion and functional analysis of the cloned fragment allows us to map the genes precisely on the fragment, establishes the direction in which rpod is transcribed, and reveals the existence of at least one new gene in the vicinity. a closely homologous, smaller fragment of escherichia coli dna, also cloned into lambda, contains rpod ...1979160566
[use of the antibody neutralization test to study water]. 1979160876
[results of 28 years of observations of the circulation of biologically nonuniform varieties of salmonella typhimurium]. 1978161090
[food poisoning in a hospital with salmonella hadar (author's transl)]. 1979161372
the effects of sodium metaperiodate on t and b lymphocytes. 1975163144
the effects of humoral, cellular and non-specific immunity on intracerebral bordetella pertussis infections in mice.when mice were injected intracerebrally with doses of bordetella pertussis vaccine greater than 5 imd 50 and challenged intracerebrally 14 days later with virulent b. pertussis there was an immediate reduction in the numbers of organisms. an analysis of this in vivo bactericidal effect has shown that large doses of an unrelated vaccine, salmonella typhosa, equivalent in cell mass to about 50 imd 50 of b. pertussis vaccine can achieve this effect, so for such doses the effect must be partly non-s ...1975163275
inactivation of viruses and bacteria by ozone, with and without sonication.selected organisms with public health significance were placed in a reaction chamber for treatment by ozonation, by ozonation and sonication, by sonication, or by sonication during oxygenation. vesicular stomatitis virus, encephalomyocarditis virus, gdvii virus, staphylococcus aureus, pseudomonas fluorescens, salmonella typhimurium, enteropathogenic escherichia coli, vibrio cholerae, and shigella flexneri were inactivated by treatment with ozone. when microorganisms were suspended in phosphate-b ...1975163616
control of expression of the pyr genes in salmonella typhimurium: effects of variations in uridine and cytidine nucleotide pools.the differential rate of synthesis of five of the pyrimidine biosynthetic enzymes coded for by pyrb-f, and the endogenous concentrations of the individual pyrimidine nucleotides were determined in specially constructed mutants of salmonella typhimurium. in the mutants employed the different pyrimidine nucleotide pools may be manipulated individually during exponential growth. the results obtained indicate the following. (i) the expression of pyrb, pyre, and pyrf is controlled by a uridine nucleo ...1975163814
treatment and control of neonatal diarrhea in calves.treatment and control of acute neonatal diarrhea in calves are outlined and discussed. the difficulty in making a definitive etiological diagnosis makes effective treatment and control also difficult and largely empirical. physiological events in calves with diarrhea are known, and fluid therapy is directed toward treating dehydration and acidosis. whether affected calves should receive antibacterial agents orally is an open question. principles of control of diarrhea in calves are outlined and ...1975163850
mechanism of the suppressive effect of interferon on antibody synthesis in vivo.mouse interferon preparations significantly suppress the in vivo antibody response to sheep red blood cells (srbc), a thymus-dependent antigen, and to salmonella typhimurium lipopolysaccharide (lps), a thymus-independent antigen. it is also possible to effect the late responses of antigen sensitive "memory" cells observed during secondary immunization by administration of interferon prior to primary immunization. the immunosuppressive activity of interferon was time- and dose-dependent. maximum ...1975163863
travelers' diarrhea and toxigenic escherichia coli.in a group of 133 united states students studied for 18 days after arriving in mexico, diarrhea developed in 38 (29 per cent). diarrhea rarely began before the fourth day, and the mean onset was 13 days after arrival. symptoms lasted an average of 3.4 days but persisted in 21 per cent of sick students. heat-labile enterotoxin-producing escheria coli was found in the stools of 72 per cent of sick and 15 per cent of healthy students. none had heat-labile esch. coli when they entered mexico. the in ...1975163964
effect of infectious bursal disease on the response of chickens to s typhimurium and e coli infections. 1975164080
the effect of cyclophosphamide on the defense to infection in calves. 1975164724
comparative studies on the reactivity of t-cells and non t-cells in lymphocyte transformation experiments and cytotoxicity tests. 1975165006
detection of carcinogens as mutagens: bacterial tester strains with r factor plasmids.we described previously a simple test on petri plates for detecting chemical carcinogens as mutagens, using an especially sensitive set of bacterial strains to detect mutagenic acitivty and a mammalian liver extract for carcinogen activity. we now extend the utility of the method by introducing two new bacterial strains which can detect with great sensitivity many carcinogens which we did not detect before or detected with less sensitivity. among these carcinogens are aflatoxin b-1, sterigmatocy ...1975165497
fetal malnutrition and postnatal immunocompetence. 1975165712
n-acetylmannosamine kinase. 1975166277
[studies to the in-vitro-effectiveness of spectacillin (author's transl)].in this study the sensibility of important disease germs of a clinical and an ambulatory test material has been investigated to the substances "epicillin" and "ampicillin". thereby could be found that 67% (43%) of the e. coli and 55% (36%) of the proteus type, as well as 96% (96%) of the enterococcus type of the ambulatory (clinical) test material were sensitive to epicillin and ampicillin. staphylococcus not producing penicillinase, were well-sensitive, while staphylococcus producing penicillin ...1975166291
antigen-stimulated changes in cyclic nucleotide levels in the mouse.mice injected intravenously with sheep erythrocytes (srbc) demonstrate a transient increase in splenic camp levels (4-fold), which peak at 2 min after injection and return to basal levels by 20 min. in addition to the change in camp, an increase in splenic cgmp levels (1.5-fold) occurs beginning 5-10 min after srbc injection, and persists for up to 7 days. during this period camp levels remain at or below control levels in the spleen. there is no change in 3':5' cyclic nucleotide levels in the l ...1975166385
estimation of in vivo aminoacylation by periodate oxidation: trna alterations and iodate inhibition. 1975166571
interferon production in mice by the capsular polysaccharide of klebsiella pneumoniae.the capsular polysaccharide of klebsiella pneumoniae (cps-k) type 1, kasuya strain, induces interferon production in the blood of mice when injected intravenously. cps-k resembles bacterial endotoxin (lipopolysaccharide) in the time pattern of interferon production, with peak levels 2h after injection. cps-k on a weight basis exhibits a more potent interferon-inducing effect than lipopolysaccharide. the active substance responsible for the interferon-inducing activity of cps-k is the neutral cps ...1975166921
comparison of the tumorigenic effects of chemical carcinogens and hormones. 1975166971
carbamylphosphate synthetase from salmonella typhimurium. regulations, subunit composition, and function of the subunits.carbamylphosphate synthetase was purified to homogeneity from a derepressed strain of salmonella typhimurium by a procedure based on affinity chromatography employing immobilized glutamine. the enzyme catalyzes the synthesis of carbamylphosphate from either ammonia or glutamine together with atp and bicarbonate. the atp saturation curve of either nitrogen donor is sigmoidal (n equals 1.5) but the affinity for atp is higher with ammonia. in addition to the feedback inhibition by ump and activatio ...1975166993
inactivation of salmonella phosphoribosylpyrophosphate synthetase by oxidation of a specific sulfhydryl group with potassium permanganate.phosphoribosylpyrophosphate synthetase from salmonella typhimurium contains four cysteine residues per subunit. three of these react readily with 5, 5'-dithiobis(2-nitrobenzoic acid) (dtnb), forming an active derivative with kinetic and physical properties similar to the native enzyme, but one reacts only under denaturing conditions. stoichiometric amounts of kmno4 inactivate the dtnb-treated enzyme. the loss of activity is correlated with the oxidation of the remaining cysteinyl group to cystei ...1975167011
a procedure for removing red cells and dead cells from lymphoid cell suspensions.a procedure is described for simultaneously removing red cells and dead cells from lymphoid cell suspensions, based on the observation that when populations of lymphoid cells are centrifuged on a mixture of isopaque/ficoll, dead cells and red cells sediment whereas viable cells float. the technique very efficiently removed red cells from a wide range of lymphoid cell suspensions and eliminated lymphocytes killed by mechanical stress, by antibody and complement and by prolonged tissue culture. th ...1975167077
mutagenicity testing with salmonella typhimurium strains. ii. the effect of unusual phenotypes on the mutagenic response.the enhanced sensitivity of some salmonella typhimurium strains to the mutagenic action of a number of chemicals appears to be due to the defect in the uvrb gene product and not to an inability to produce h-2-s or to the absence of formic acid hydrogenlyase which also characterizes these strains.1975167280
cyclic 3', 5'-adenosine monophosphate phosphodiesterase mutants of salmonella typhimurium.positive selection procedures for mutants of salmonella typhimurium lacking cyclic 3', 5'7-adenosine monophosphate (camp) phosphodiesterase have been devised. the gene (cpd) coding for this enzyme has been located on the chromosome and shown to be 25% co-transducible with metc using phage p22. the mutants have been used to investigate the role of the enzyme in the control of genes whose expression is known to be dependent on camp. significant alterations in the regulation of some but not others ...1975168178
immunologic effects of neonatal infection with mouse thymic virus.mouse thymic virus is a herpesvirus that causes extensive thymic necrosis when given to newborn mice. during the time of acute infection spleen cells have markedly diminished reactivity to t cell phytomitogens and to allogeneic cells and are incapable of effecting a primary in vitro response to a "t-dependent" antigen; responses to b cell mitogens and to a t-independent antigen are unimpaired. spleens from acutely infected mice have low theta antigen normal numbers of immunoglobulin-bearing cell ...1975168265
pyrr identical to pyrh in salmonella typhimurium: control of expression of the pyr genes.mutants of salmonella typhimurium showing constitutive synthesis of the pyrimidine biosynthetic enzymes coded for by the pyra-f genes (g. a. o'donavan and j. c. gerhart, 1972) have been reinvestigated. the high rate of expression of the pyrb-f genes in these mutants as well as their pyrimidine excretion is shown to be due to mutations in the gene pyrh encoding uridine 5'-monophosphate kinase. thus, the term pyrr used for these mutants should be replaced by the designation pyrh.1975169229
tryptophan biosynthesis in salmonella typhimurium: location in trpb of a genetic difference between strains lt2 and lt7.salmonella typhimurium prototrophs carrying a trpr mutation synthesize tryptophan biosynthetic enzymes constitutively. when feedback inhibition of anthranilate synthetase but not 5'-phosphoribosylpyrophosphate phosphoribosyltransferase activity was by-passed by growing cells on media supplemented with anthranilic acid, all trpr prototrophs overproduced and excreted tryptophan. however, the rate of tryptophan production depended on both the ancestry of the trpr strain and the integrity of its trp ...1975169230
coordinate regulation of adenylate cyclase and carbohydrate permeases by the phosphoenolpyruvate:sugar phosphotransferase system in salmonella typhimurium.adenylate cyclase (ec 4.6.1.1) and several carbohydrate permeases are inhibited by d-glucose and other substrates of the phosphoenolpyruvate:sugar phosphotransferase system. these activities are coordinately altered by sugar substrates of the phosphotransferase system in a variety of bacterial strains which contain differing cellular levels of the protein components of the phosphotransferase system: enzyme i, a small heat-stable protein, and enzyme ii. it is suggested that the activities of aden ...1975169265
effect of klebsiella pneumoniae enterotoxin on intestinal transport in the rat.the effects on intestinal transport of either a semipurified preparation of enterotoxin elaborated by klebsiella pneumoniae or similaryly prepared control material were tested by marker perfusion studies in the small intestine of rats. at a concentration of 2 mg/ml, the enterotoxin produced net secretion of water, na, and cl in both jejunal and ileal segments; hco3 transport was not affected. net secretion was evident within 30 min after intorduction of the toxin and was maximal after 90 min. th ...1975169297
[salmonellosis: retrospective study of 136 cases hospitalized at the c.h.u. of tours].136 cases of salmonellosis were seen in the tours hospital center from 1965 to 1971. salmonella typhi produced 32 cases of typhoid fever and 2 focal infections: a bacterial pleural effusion and an osteoarthritis. salmonella para b induced 16 cases of typhoid fever. all these 50 patients were given chloramphenicol that was effective in vitro and in vivo as well. they usually exhibited very few and mild signs or symptoms but long lasting fever. complications were very rare. there was no death. par ...1975169589
recent developments in immunization against diarrheal diseases. 1975169592
action of polymyxin b on bacterial membranes: morphological changes in the cytoplasm and in the outer membrane of salmonella typhimurium and escherichia coli b.though the primary action of the cationic antibiotic polymyxin b is against the membrane of susceptible bacteria, severe morphological changes are detected in the cytoplasm. using fluorescence microscopy and a mono-n-dansyl-polymyxin b derivative, we could demonstrate aggregations of the antibiotic with cellular material, possibly nucleic acids and/or ribosomes. these aggregations were only produced by minimum inhibitory or higher concentrations of the antibiotic as shown with salmonella and esc ...1975169730
regulation of gmp reductase in salmonella typhimurium.the levels of guanosine 5'-phosphate reductase (ec 1.6.6.8) in salmonella typhimurium appear to be modulated by changes in the ratio of the adenine and guanine nucleotide pools. alterations of this ratio may be induced by high levels of guanosine in the culture medium or by genetic lesions in one of several purine interconversion enzymes, such as pur a or pur b mutants. the induction of the reductase requires transcription and translation processes and, in contrast to earlier observation with es ...1975169910
characterization of monkey peripheral neutrophil granules during infection.rhesus monkey (macaca mulatta) neutrophils were shown to contain the azurophilic granule maker enzymes myeloperoxidase and beta-glucuronidase but were deficient in the specific granule markers alkaline phosphatase (akp) and lysozyme. isopycnic centrifugation of leukocyte homogenates on linear sucrose gradients resulted in cosedimentation of myeloperoxidase and beta-glucuronidase with an equilibrium density of 1.18. after an intravenous inoculation of monkeys with salmonella typhimurium akp activ ...1975170208
wildlife and environmental health: raccoons as indicators of zoonoses and pollutants in southeastern united states.inasmuch as terrestrial fauna are an integral part of our natural environment and are directly exposed to disease and pollutants, it follows that certain wild populations could serve to detect subtle alterations within ecosystems. a collection of studies on raccoons is presented to stimulate other researchers to develop the potential of our wildlife resources as monitors of environmental health. raccoons have been used as serologic sentinels for st louis encephalitis and venezuelan equine enceph ...1975170239
studies of the quaternary structure and the chemical properties of phosphoribosylpyrophosphate synthetase from salmonella typhimurium.phosphoribosylpyrophosphate (prpp) synthetase (ec 2.7.6.1) was purified to virtual homogeneity from salmonella typhimurium cells by a modification of previously published procedures. the molecular weight of the subunit was determined to be 31,000 +/- 3,000 by polyacrylamide gel electrophoresis in sodium dodecyl sulfate and sedimentation equilibrium analysis of the enzyme dissolved in 6 m guanidine hydrochloride. the amino acid composition of the enzyme was determined. proline was identified as t ...1975170262
regulation of intracellular adenosine cyclic 3':5'-monophosphate levels in escherichia coli and salmonella typhimurium. evidence for energy-dependent excretion of the cyclic nucleotide.sugars and other energy sources were found to lower intracellular concentrations of adenosine 3':5'-monophosphate (cyclic amp) in strains of escherichia coli and salmonella typhimurium which were deficient for cyclic amp phosphodiesterase. this effect required the presence of the specific transport system responsible for entry of that sugar into the cell and depended on the intracellular catabolic enzymes. metabolizable sugars were more effective than nonmetabolizable sugars in reducing cellular ...1975170265
mutants of salmonella typhimurium responding to cysteine or methionine: their nature and possible role in the regulation of cysteine biosynthesis.nineteen mutants of salmonella typhimurium responding to either cysteine or methionine (cym) have been identified amongst cysteine (cys) and methionine (met) auxotrophs. their growth responses to known intermediates in the related pathways of cysteine and methionine biosynthesis and complementation patterns in abortive transduction tests divided the mutants into six groups. results of conjugation, cotransduction and deletion mapping experiments substantiated these groups, each of which carried a ...1975170364
food poisoning--four unusual episodes.four unusual outbreaks of food poisoning occurring in the dunedin health district during the period 1971-1973 are described. these involved a contaminated cordial, a death associated with a clostridium perfringens outbreak, salmonellosis and infectious hepatitis in persons eating uncooked shellfish and symptoms associated with the ingestion of a normally edible fish--the trumpeter.1975170567
altered dna synthesis in a mutant of salmonella typhimurium that channels bacteriophage p22 toward lysogeny.pox-1, a mutant of salmonella typhimurium, strongly channels p22 toward lysogeny. viral dna synthesis in this slow-growing mutant is delayed to a greater extent than viral protein synthesis. the relative enhancement of c2 repressor synthesis results in much higher repressor/dna synthesis ratios in pox-1 than in wild-type cells. this probably accounts for the high frequency of lysogenization.1975171446
host influence on the activity of genes c1 and c3 in regulating the decision between lysis and lysogency in bacteriophage p22.a polymyxin b-sensitive mutant of salmonella typhimurium (pox-1) channels all infecting wild-type p22 toward lysogenization. the efficiency of this channeling is sufficiently high that p22c+ (wild type) cannot form plaques on pox-1; phage mutants defective in repressor synthesis (p22c1, c2, c3) or refractory toward repressor (p22vir b) can form plaques. the lytic growth of all phages which have a functional c1 gene is retarded in pox-1; this retardation is seen even in phages which cannot make r ...1975171449
[the mutagenic effect of methyl methanesulfonate (mms) in vitro and in the host-mediated assay (author's transl)].the concentration- and time-dependent genetic activity of methyl methanesulfonate (mms) was investigated in vitro and in the host-mediated assay using four different indicator organisms. dose/effect curves achieved with the different indicator organisms are similar.1975172045
endotoxic lipopolysaccharides stimulate steroidogenesis and adenylate cyclase in adrenal tumor cells.lipopolysaccharides (endotoxins) from escherichia coli, serratia marcesens and salmonella typhosa stimulated steroid production in y-1 adrenal tumor cells in culture with a latent period of 3-4 h. lipid a, derived from escherichia coli lipopolysaccharide, also stimulated steroidogenesis. lipopolysaccharides and lipid a also stimulate adenylate cyclase activity and cause rounding of the cells. in contrast, lipopolysaccharides do not stimulate steroidogenesis in receptor-deficient adrenal tumor ce ...1975172155
[resistance to association of antibiotics (polymyxin and penicillin) in relation to cell concentration of two bacterial species in the same inoculum. complementary inoculum effect].dense suspensions of sa. typhi (polys penr) and of st. aureus (polyr pens) proliferate on gelose medium added with the two antibiotics only if the inoculum is mixed. the growth is probably due to the partial neutralization of the antibiotics following the formation of complexes between these antibiotics and some constituents of the two strains.1975172250
on the mechanism of inhibition of enzyme induction in escherichia coli by distamycin a.the mechanism of the interference of the antiviral antibiotic distamycin a with the bacterial cell has been investigated. labelled distamycin a is firmly bound by e. coli cells and the binding process does not require metabolic energy as indicated by the use of inhibitors. the antibiotic does not induce gross alteration in the cell membrane but inhibits cyclic amp accumulation in the cells exposed to a glucose-free medium. this inhibition is concomitant with that exerted on the synthesis of an i ...1975172369
pathogenesis of salmonella-mediated intestinal fluid secretion. activation of adenylate cyclase and inhibition by indomethacin.salmonella typhimurium, an organism that invades intestinal mucosa but does not elaborate a traditional enterotoxin, evokes ileal secretion by causing alterations in active sodium and chloride transport mechanisms. to evaluate the possibility that these changes in transport might be related to the adenylate cyclase-cyclic amp or na+-k+-adenosine triphosphatase (atpase) systems, mucosal adenylate cyclase, camp phosphodiesterase, na+-k+ and mg++ atpase activities, and camp concentrations were meas ...1975172399
immune response and the b blood group locus in chickens.chickens of three blood group genotypes, b1b1, b1b2 and b1b19, were compared in their ability to produce antibodies. the b locus is the major histocompatibility locus in this species. homozygous b1 pullets had significantly higher adult mortality than did the b1 heterozygotes. in two separate experiments the b1b1 females produced significantly fewer antibodies to salmonella pullorum than did the b1 heterozygotes. also the b1b1 pullets responded with lower antibody titers following immunization w ...1975172405
bacterial food-poisoning. 1975173111
oxygen-18 studies of the mechanism of pyrophosphoryl group transfer catalyzed by phosphoribosylpyrophosphate synthetase. 1975173242
cysteine biosynthesis in salmonella typhimurium: the presence of atp-sulfurylase and aps-kinase in various cysteine-requiring mutants.enzymatic tests were performed on a series of cysteine-requiring mutants for the presence of the sulfate activating enzymes. atp-sulfurylase (sulfate adenylyltransferase ec 2.7.7.4) and aps-kinase (adenylylsulfate kinase ec 2.7.1.25). the enzymatic products adenosine 5'-[35s]sulfatophosphate and adenosine 3'-phosphate 5'-[35s]sulfatophosphate were identified by paper electrophoresis and measured quantitatively without elution from the paper. cys mutants mapping in cistrons, a, h, i, j, g, and ea ...1975173451
increased susceptibility to bacterial infection as a sequela of exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin.the effects of subclinical levels of 2,3,7,8-tetrachloridibenzo-p-dioxin (tcdd) on the response of mice to infection with either salmonella bern or herpesvirus suis, also known as pseudorabies virus, are reported. tcdd is a contaminant of certain commercially useful chemicals, such as chlorinated phenols or herbicides. it has been shown to cause thymic atrophy and to suppress cell-mediated immunity in laboratory animals. sublethal levels of tcdd were used: 0.5, 1,5, 10, or 20 mug/kg, given throu ...1975173655
transformation of escherichia coli by chromosomal deoxyribonucleic acid from salmonella typhi.the genetic transformation of escherichia coli k-12 with chromosomal deoxyribonucleic acid purified from salmonella typhi is described.1976173714
tumor regression caused by endotoxins and mycobacterial fractions.a transplantable hepatocarcinoma of guinea pigs was used as an experimental model for immunotherapy of cancer. earlier work showed that complete regression of 6- to 7-day-old tumors could be obtained in about 60% of cases by inoculation of the tumors with live bcg or certain fractions of bcg attached to minute oil droplets and suspended in tween-saline. one of the most essential fractions was p3, a nonsensitizing, nonantigenic trehalose mycolate related to, but not identical with, cord factor. w ...1975173865
inhibition of lipopolysaccharide-initiated activation of serum complement by polymyxin b.treatment of bacterial lipopolysaccharides (endotoxins) isolated from salmonella minnesota r595 or purified lipid a with the antibiotic polymyxin b has been demonstrated to abrogate the ability of these molecules to activate serum complement. the inhibition is a function of the ratio of polymyxin b to lipopolysaccharide.1976175019
occurrence of reo-like calf viruses in young children with acute gastroenteritis. diagnoses established by electron microscopy and complement fixation, using the reo-like virus as antigen.in the course of a six-month-study of acute gastroenteritis in children of ages up to six years, a reo-like virus was found in 54 per cent of the faecal specimens obtained at an early stage of the disease, using electron microscopy as screening test. by means of a concentrated complement fixation antigen, composed of a related calf diarrhoea virus cultivated in tissue culture, the rise in titre was found to be significant in 96 per cent of the patients whose faeces contained the reo-like virus. ...1976175639
release of xenotropic type c rna virus in response to lipopolysaccharide: acitivity of lipid-a portion upon b lymphocytes.the present studies demonstrate that lipopolysaccharide (lps) causes the release of endogenous xenotropic type-c rna virus from balb/c spleen cells. the evidence suggests that virus release is stimulated by the lipid-a portion of lps and primarily involves an action of lps on b lymphocytes. lps had little or no effect on virus release by t lymphocytes, macrophages, or fibroblasts. these results indicate that the differentiated state of the cell plays an important role in the regulation of endoge ...1976176273
orphan airlift. enteric pathogens isolated from vietnamese children immigrating to the united states.isolation studies for bacterial and parasitic agents were carried out on stool specimens from vietnamese infants at the time of their mass airlift to the united states. one or more bacterial pathogens were found in 49% of the 367 stool specimens cultured. the isolates included enteropathogenic escherichia coli (161), shigella (16), salmonella (15), but no salmonella typhi or vibrio cholerae. parasites identified in 88 stool specimens included giardia lamblia (10), ascaris lumbricoides (7), and e ...1976176481
[obtaining the beta-globulin fractions from swine and cattle sera and a study of their immunological activity].the rivanol precipitation was used to obtain beta-globulin fractions from specific swine sera against edema disease, paratyph and aujeszky's disease as well as from normal ovine and swine sera. agar electrophoresis revealed that the preparations produced contained beta-globulin (86 per cent), gamma-globulin (5 per cent), and alpha2-globulin (9 per cent). the beta-globulin preparations were studied for the presence of antibodies against e. coli, salmonellae, staphylococci, myxovirus parainfluenza ...1976176771
action of polymyxin b on bacterial membranes: phosphatidylglycerol- and cardiolipin-induced susceptibility to polymyxin b in acholeplasma laidlawii b.to identify the polymyxin receptor molecules in the membranes of living microorganisms, fusion of intact acholeplasma laidlawii b with lipid vesicles was investigated according to the procedure of grant and mcconnell (1973). the naturally polymyxin-resistant a. laidlawii b was treated with phospholipid vesicles prepared from purified phospholipids of the polymyxin-susceptible salmonella typhimurium g30. a. laidlawii b absorbed between 15 and 45% of its own lipid content of the added tritium-labe ...1976176930
growth rate modulation of four aminoacyl-transfer ribonucleic acid synthetases in enteric bacteria.the specific activities of arginyl- glutamyl- seryl-, and valyl-transfer ribonucleic acid (trna) synthetases were measured in the wild-type and mutant strains of salmonella typhimurium lt2 and escherichia coli b/r. in media restricted only by carbon and energy source availability, the specific activities of all four enzymes were proportional to the growth rate, with the exception of seryl-trna synthetase in s. typhimurium, which remained essentially constant. structural gene densities were calcu ...1976177401
[bacterial resistance factors as vectors for gene manipulation and gene therapy (author's transl)].bacterial resistance factors are extrachromosomal elements, consisting of circular closed, double stranded dna. they may contain genes which make the host bacterium resistant to certain antibiotics. such resistance factors have become important vectors for selective replication of specific segments of all kinds of dna. suitable dna segments are obtained by treating dna with restriction endonucleases of defined cutting properties. they can then be linked to the respective vector. it was thus poss ...1975177861
in vivo synergy between 6 beta-amidinopenicillanic acid derivatives and other antibiotics.both an oral and a parenteral form of a 6beta-amidinopenicillanic acid derivative were found to have appreciable activity against gram-negative bacteria and poor activity against gram-positive bacteria in vivo. when administered orally or parenterally, definite synergy was demonstrated between the amidinopenicillins and ampicillin, amoxicillin, benzylpenicillin, cefazolin, or carbenicillin in infections with a number of gram-negative bacteria, including klebsiella, enterobacter, escherichia, pro ...1976178275
effect of delayed evisceration on the microbial quality of meat.the postomortem invasion of muscle and other tissues by bacteria from the intestinal tract was studied with the use of radioactive tracers. the injection of 14c-labeled bacteria or spores into the intestines of guinea pig carcasses within 24 h of death resulted in the rapid spread of 14c throughout carcasses. when live bacteria were injected along with the labeled cells, it was not possible to isolate viable organisms from the body tissues if the living animal had been exposed to the bacteria. i ...1976178276
adenyl cyclase activity of mouse liver membranes after incubation with endotoxin and epinephrine.adenyl cyclase activity in isolated mouse liver cell membranes was stimulated two-fold by endotoxin. furthermore, endotoxin inhibited epinephrine induction of adenyl cyclase activity, apparently through interruption of the phospholipid moiety of the enzyme complex.1976178522
the role of camp in flagellation of salmonella typhimurium.a mutational alteration either in adenylate cyclase (cya-) or in cyclic-3'5'-amp (camp) receptor protein (crp-) rendered salmonella typhimurium incapable of producing flagella. the amount of mrna specific for flagellin in these mutants was almost negligible when assayed in an in vitro protein synthesizing system. a secondary mutation cfs, partially suppressing the cya- mutation, was identified among the revertants of cya-. a mutation in the same cistron as cfs resulted in a non-flagellate phenot ...1976178991
[health aspects of the study of bdellovibrio bacteriovorus as a natural factor in the self-purification of reservoirs]. 1975179245
inhibition of growth and aspartokinase activity of salmonella typhimurium by thialysine.thialysine (s-2-aminoethyl cysteine) is an analog of lysine and has been reported to inhibit the lysyl-trna synthetase activity of escherichia coli. this analog inhibits the growth of salmonella typhimurium when added to glucose minimal medium at concentrations of 1.25 mm or greater. the addition of lysine with thialysine restores the normal growth rate, whereas, methionine, valine, or leucine each enhances the growth inhibition casued by thialysine. enzyme assays demonstrate that thialysine inh ...1976179582
further studies on the relative antiviral efficacies of interferons induced by poly i:c and mengo virus.mouse serum interferons induced by polyi:c, vesicular stomatitis virus (vsv), reovirus, and mengo virus were assayed in monolayers of mouse l-929 cells by the plaque-reduction method using both vsv and mengo as challenge viruses. titers obtained with mengo virus as challenge were all lower than with vsv. with the interferons induced by vsv, reovirus, and ployi:c, the reductions were of the order of two- to three-fold. with mengo virus-induced interferon the reduction was much greater (about 17-f ...1976179687
effects of crp mutations on adenosine 3',5'-monophosphate metabolism in salmonella typhimurium.wild-type salmonella typhimurium could not grow with exogenous cyclic adenosine 3',5'-monophosphate (amp) as the sole source of phosphate, but mutants capable of cyclic amp utilization could be isolated provided the parental strain contained a functional cyclic amp phosphodiesterase.all cyclic amp-utilizing mutants had the growth and fermentation properties of cyclic amp receptor protein (crp) mutants, and some lacked cyclic amp binding activity in vitro. the genetic defect in each such mutant w ...1976179973
laboratory investigation of diarrhea in travelers to mexico: evaluation of methods for detecting enterotoxigenic echerichia coli.a laboratory investigation was conducted on cultures collected from travelers before, during, and after a trip to mexico to characterize the etiology of traveler's diarrhea. four laboratory methods for detecting enterotoxigenicity of escherichia coli were evaluated: the infant mouse assay, the chinese hamster ovary (cho) cell assay, the y1 adrenal cell assay, and the rabbit ileal loop. although a number of common enteric pathogens were identified as a cause of traveler's diarrhea, including six ...1976180047
natural infections of guinea-pigs. 1976180326
does cyclic amp have a role in the pathogenesis of fever in the rabbit? 1976180436
[hygienic evaluation of the finding of the causative agents of food poisoning in food products]. 1975180687
[the inhibitory effect of alkyl-aryl-sulfonate on the swarming of proteus bacteria].tests were carried out on 16 strains of proteus to determine the smallest amount of alkylarylsulfone that prevents complete swarming of the bacteria, restricting it to band only 1-2 mm wide. this was achieved by adding 0.0075% of detergent to gassner's medium. the result was easily visible on the surface of inoculated plates. it was also shown that this inhibitory effect on the flagellar apparatus of proteus and also salmonella was purely temporary being due to a reversible reduction of this app ...1975180922
stimulation of lymphocyte proliferation by killed mycobacteria and other bacterial species.killed mycobacteria and some mycobacterial fractions induced spleen cells from normal c3h mice to incorporate tritiated thymidine to a relatively high degree. thymocytes under the same conditions were not activated. however, incorporation of thymidine was significantly increased when mixtures of thymus and spleen cells were cultured in the presence of the inducers. a similar activation of spleen cells was displayed in the presence of gram-positive and gram-negative non-mycobacterial species.1976181325
the effect of bacterial infections on ketone concentrations in rat liver and blood and on free fatty acid concentrations in rat blood.the concentrations of cytoplasmic lactate and pyruvate and the nad+/nadh ratio and the concentrations of mitochondrial acetoacetate, beta-hydroxybutyrate, and the nad+/nadh ratio were determined in normal, fed, and fasted rats, and in rats infected with streptococcus pneumoniae, francisella tularensis, and salmonella typhimurium. the various infections were found to have little or no effect on the cytoplasmic parameters. in normal rats, fasting caused a marked increase in blood and hepatic keton ...1976181658
adjuvant disease induced by mycobacteria, determinants of arthritogenicity.genetic, endocrine and immunological factors are probably involved in adjuvant polyarthritis. the nature of the vehicle and of the mycobacterial components administered also has a major influence. it was originally assumed that arthritogenicity and adjuvanticity of mycobacterial fractions such as wax d were intimately related. our previous findings showed that the water soluble adjuvant (wsa) of m.smegmatis which could substitute for mycobacterial cells in freund's complete adjuvant and induce d ...1976181972
simultaneous selection of mutants in gluconeogenesis and nucleoside catabolism in salmonella typhimurium.penicillin selection in minimal thymidine medium, used to select mutants in deoxynucleoside catabolism, also yields a high percentage (37%) of mutants in fructose diphosphatase. the expression of the deo regulon is retarded in the mutants defective in the glyconeogenic pathway.1976182268
non-specific immunity after local immunization.the most important advantage of local immunization is the non-specific effect. the active protection test in mice shows an immunity against oral infection with virulent salmonella typhimurium bacteria after oral immunization with heterologous inactivated enterobacteria. we observed the same non-specific protection in a viral model. after oral immunization with inactivated s. typhimurium bacteria, the mice are protected against oral infection with a virulent parapoliomyelitis virus. in the phagoc ...1976182583
effect of polymyxin on the ultrastructure of the outer membrane of wild-type and polymyxin-resistant strain of salmonella.the effect of polymyxin on two sets of salmonella mutants was studied by thin-section and scanning electron microscopy. polymyxin (in increasing concentrations, starting just below bactericidal effect) caused the appearance of the previously described rodlike projections on the cell surface of wild-type (smooth, polymyxin-sensitive) bacteria. these projections seemed to involve the outer membrane of the cell wall. in rough mutants, which are deficient in lipopolysaccharide, the projections were ...1976182675
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