Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| deficiency of serum bactericidal activity against salmonella typhimurium in sickle cell anaemia. | systemic salmonellosis is a recognized complication of sickle cell anemia (sca). in our initial study of sca host defences against salmonella, we evaluated the bactericidal activity of serum against salmonella typhimurium. when compared to controls, sera from eight out of nineteen sca patients were deficient in bactericidal function. levels of factor b, haemolytic complement and agglutinating antibody were similar in sca and control sera. however, abnormalities that might theoretically account f ... | 1977 | 342154 |
| mutagenicity of carcinogenic mycotoxins in salmonella typhimurium. | 1978 | 342092 | |
| mutagenicity of some congeners of benzidine in the salmonella typhimurium assay system. | the analogs of benzidine were assay for mutagenicity using salmonella typhimurium ta-98 and ta-100 and a mouse liver enzyme preparation. only 4-aminobiphenyl produced both frameshift and base pair substitution mutations and 3,3'-dichlorobenzidine was the only compound which was mutagenic without the mammalian enzyme factor. when hydrochloride salts of the parent compounds were made to improve their stability for animal feeding experiments, the mutagenicity for the salmonella tester strains was r ... | 1978 | 342090 |
| sodium-dependent binding of p-nitrophenyl alpha-d-galactopyranoside to membrane vesicles isolated from salmonella typhimurium. | 1978 | 341975 | |
| the response of foetal sheep to the somatic and flagellar antigens of salmonella typhimurium. | following the injection of polymeric flagellin (pol), foetal sheep older than 70 days gestation produced haemagglutinating antibody and synthesized igm. the maximum titre of antibody in the blood increased with the age at which the foetus was injected. all foetuses synthesized 2-mercapto-ethanol-sensitive antibodies, while older foetuses (approximately 120 days gestation) also produced 2-mercaptoethanol-resistant antibodies and synthesized igg1. during the primary immune response, there was a po ... | 1977 | 341873 |
| [physiological characteristics of salmonella typhimurium treated with penicillin]. | growing bacteria of the two strains of salmonella typhimurium differing in the sensitivity levels to uv-light formed multinuclear non-septal filaments in the penicillin-containing nutrient medium. the maximum number of the lifefull filaments was formed by the 4th hour of incubation in the beaf-peptone broth at a temperature of 37 degrees c in the presence of 5 gamma/ml of penicillin. the strains exposed to penicillin were less sensitive to uv-light. exclusion of penicillin from the nutrient medi ... | 1978 | 341800 |
| endocytosis of salmonella typhimurium 395 ms and mr10 by hela cells. | monolayer of hela cells were examined for their ability to endocytose salmonella typhimurium 395 ms (wild) and mr10 (chemotype rd). monolayers treated with the glycolytic inhibitors iodoacetic acid (iaa) or n-ethylmaleimide (nem) or the respiratory inhibitor sodium azide (nan3) or cytochalasin b (cb) were incubated with s. typhimurium. the numbers of cell-associated (intracellular plus cell-membrane attached extracellular) and intracellular bacteria were determined by viable counts, together wit ... | 1977 | 341644 |
| association of some enterobacteria with the intestinal mucosa of mouse in relation to their partition in aqueous polymer two-phase systems. | the association of enterobacteria with mouse intestinal mucosa has been investigated by pumping heat-killed, radioactively-labelled bacteria through the gut lumen in vitro. approximately 20 cm of the small intestine proximal to the ileo-caecal valve was rinsed, excised and maintained in an organ bath. by using two different bacteria labelled with different radioactive isotopes, the relative association of the two bacterial pumped through the same piece of gut was determined. cross-labelling show ... | 1977 | 341643 |
| the structure of the cyscdhij region in unstable cysteine or methionine requiring mutants of salmonella typhimurium. | a genetic method was devised to test the hypothesis that in some cysteine or methionine requiring (cym) mutants of salmonella typhimurium suppression of auxotrophy is due to an insertion at the site of the cym mutation. it was found that suppressed strains have an insertion of about 9kb in the cyscdhij region and that in unstable suppressed strains it is the instability of this insertion which results in the segregation of cym auxotrophs. | 1977 | 340911 |
| an effect of f-like plasmids on the maintenance of flac in a dnac mutant of salmonella typhimurium. | flac maintenance was aberrant at permissive temperature in a temperature-sensitive dnac mutant of salmonella typhimurium when the normally resident plt2 plasmid was present. flac was, however, efficiently transferred into the dnac plt2+ strain and the resulting flac derivative was almost as efficient in transferring flac as was dnac+ plt2+ flac strains indicating that aberrant flac maintenance was not associated with appreciable inhibition of transfer replication. a range of f-like plasmids beha ... | 1977 | 340909 |
| biochemical characteristics and in-vitro drug sensitivity of salmonella typhimurium, copenhagen variety isolated from domestic and feral pigeons, crows, a kite, chickens and animals in japan. | 1977 | 340743 | |
| quinoline: conversion to a mutagen by human and rodent liver. | quinoline, a hepatocarcinogen in rats, and 23 quinoline derivatives were tested for mutagenic activity with the ames salmonella typhimurium assay. quinoline, 5-hydroxyquinoline, and 8-hydroxyquinoline were mutagenic in strain ta 100 when aroclor 1254-induced rat (male outbred sprague-dawley) liver homogenate was present in the incubation mixture. enzyme preparations from rats pretreated with p-448-dependent aryl hydrocarbon hydroxylase inducers [3-methylcholanthrene (mca) and beta-naphthoflavone ... | 1978 | 340706 |
| the effect of defined lipopolysaccharide core defects upon antibiotic resistances of salmonella typhimurium. | 1977 | 340606 | |
| mutagenic activity of thiocarbamate herbicides in salmonella typhimurium. | 1978 | 340488 | |
| increased susceptibility of trypanosoma lewisi infected, or decomplemented rats to salmonella typhimurium. | rats infected with trypanosoma lewisi or decomplemented by injection of cobra venom factor or complement activating factor of trypanosomes were found to be more susceptible to infection with salmonella typhimurium. decomplemented rats subsequently infected with t. lewisi developed higher blood parasitemia than did normal t. lewisi infected rats. | 1978 | 340247 |
| silver sulfadiazine: lack of mutagenic activity. | silver sulfadiazine was found to be devoid of mutagenic potential in a sensitive mutagenicity assay using salmonella typhimurium. in view of the close relationship between mutagenicity in this system and carcinogenicity in animals, these findings suggest that silver sulfadiazine is apparently also devoid of carcinogenic properties. | 1978 | 340170 |
| [r-factor distribution and characteristics of the e. coli isolated from pigs]. | studied was the occurrence of the r-factors in escherichia coli isolated from pigs. it was demonstrated that in 73.3 per cent of the cases drug resistance could be transmitted to citrobacter. in this instance an occasional drop-out of the markers of resistance to kanamycin, neomycin, ampicillin, tetracycline, and chloramphenicol was observed. in the author's experiments no transmission of the marker of resistance to furazolidon was established. the transmission of the signs of resistance to kana ... | 1977 | 339513 |
| mutagenicity of fume particles from stainless steel welding. | welding fume particles collected from different welding procedures were tested for mutagenicity in escherichia coli, with the inhibition zone in pol a- as compared to pol a+, and in salmonella typhimurium, ta 100 strain. while no mutagenicity was found with mild steel welding, a mutagenic effect was established with samples from stainless steel welding. this mutagenicity was particularly associated with manual metal arc (mma) welding, and less so with metal inert-gas welding. a decrease in or an ... | 1977 | 339336 |
| mutagenicity of hydroxamic acids for salmonella typhimurium. | p-butoxyphenylacethydroxamic acid, benzohydroxamic acid, salicylhydroxamic acid, 2-naphthohydroxamic acid, indole-2-carbohydroxamic acid and benzoylaminoacethydroxamic acid were synthesized, and their mutagenicity for salmonella typhimurium strains ta98 and ta100 were determined. except for p-butoxyphenylacethydroxamic acid, all the hydroxamic acids were mutagenic for both strains. the mutagenicity progressed in the following order: 2-naphthohydroxamic acid greater than benzohydroxamic acid and ... | 1977 | 339075 |
| mutagenicity screening of five methyl carbamate insecticides and their nitroso derivatives using mutants of salmonella typhimurium lt2. | the mutagenic activity of five methyl carbamate insecticides-carbaryl, baygon, bux-ten, landrin and methomyl-and their nitroso derivatives were investigated using histidine auxotrophs-his ta98, his ta100, his ta1535, his ta1537 and his ta1538--of salmonella typhimurium lt2 derived by ames. the methyl carbamate insecticides did not cause a signficant increase in the number of revertant colonies in any of the strains used. in contrast, the nitroso derivatives of the carbamate insecticides greatly ... | 1977 | 339072 |
| carcinogen activation by human liver enzymes in the ames mutagenicity test. | liver post-mitochondrial supernatants derived from 10 individuals were used as the source of metabolic activation for carcinogens in the ames quantitative mutagenicity test using salmonella typhimurium ta 100. the liver samples were obtained from brain-dead donors and autopsy cases. the ability of human enzymes to activate aromatic amines ranged from the undetectable to highly active for 2-acetylaminofluorene. none of the samples exhibited any ability to activate benzidine. a generally low activ ... | 1977 | 339071 |
| intrasanguine host-mediated assay with salmonella typhimurium. | 1977 | 339068 | |
| nitramino acids. synthesis and biological evaluation of 1-nitroproline, 1-nitropipecolic acid, and n-nitrosarcosine. | the n-nitro derivatives of secondary alpha-amino acids, viz., 1-nitroproline (1a) (l and d), 1-nitro-dl-pipecolic acid (2a), and n-nitrosarcosine (3a), were prepared by the oxidation of the corresponding nitrosamino acids with peroxytrifluoroacetic acid. these nitramino acids (1a-3a) were not active against escherichia coli, candida albicans, pseudomonas aeruginosa, or mycobacterium smegmatis, and 1a and 2a did not show mutagenic activity in a salmonella typhimurium ta-100 system, with or withou ... | 1977 | 338899 |
| role of phagocytosis in mouse virulence of salmonella typhimurium recombinants with o antigen 6,7 or 4,12. | the quality of lipopolysaccharide has previously been shown to influence the mouse virulence of salmonella so that strains with o antigen 4,12 were more virulent than their o-9,12 sister strains. immunosuppression did not alter this o-antigen-dependent difference in virulence. i have now constructed smooth o-4,12 and o-6,7 sister hybrid strains of salmonella typhimurium. no other phenotypic differences were found between these strains; they were all "common antigen" positive. in intraperitoneal ... | 1977 | 338484 |
| a mutant of the antibiotic resistance factor r124 with altered copy number. | a mutation conferring increased antibiotic resistance on salmonella typhimurium strain 11g carrying r124 was plasmid determined; strains harbouring the mutant plasmid contained more dna as ccc plasmid than those harbouring r124. the increased copy number was manifested at all growth rates tested. | 1977 | 338336 |
| selection of an in vitro carcinogenicity test for derivatives of the carcinogen hexamethylphosphoramide. | the demonstration that hexamethylphosphoramide (hmpa) possesses potent carcinogenic properties has raised doubts about the safety of exposure to other phosphoric amides. in order to define a suitable short-term test with which to evaluate such analogues, the response of the salmonella typhimurium mutation assay of ames and cell transformation assay of styles to hmpa and 3 selected analogues has been studied. these analogues were the related leukaemogen phosphoramide, the putative non-carcinogen, ... | 1977 | 337998 |
| properties of the cell envelope and a cell-envelope protein of pseudomonas facilis. | the molecular weight of the protein moiety of a phospholipoprotein complex isolated from pseudomonas facilis has been examined with a variety of sodium dodecylsulfate-polyacrylamide gel electrophoretic systems. a molecular weight of 35 000 was determined for the protein in all analyses. a 35 000-dalton protein was present in the edta extract of p. facilis and in the cytoplasmic and outer membrane fractions, but not in the lipopolysaccharide and peptidoglycan. prior inoculation of mice with the p ... | 1977 | 337920 |
| saccharin and other sweeteners: mutagenic properties. | saccharin preparations commonly distributed as artificial sweeteners exhibited mutagenic activity in bacterial tests. when administered orally to mice, mutagenic activity was demonstrable in the urines of these animals as well as in a host-mediated assay. highly purified saccharin was not mutagenic in the direct assay, but the urines of mice to which this material had been administered exhibited mutagenic effects on one tester strain (salmonella typhimurium ta100). two other sweeteners, neohespe ... | 1977 | 337489 |
| [iron overload: effect on specific and nonspecific immunity]. | acute overload with an iron salt in mice enhanced the virulence of a relatively avirulent type of salmonella typhimurium in a dose-dependent fashion. iron administration also partly abolished specific immunity. ferritin iron did not display the virulence-enhancing effect. | 1977 | 337471 |
| transcription termination at the trp operon attenuators of escherichia coli and salmonella typhimurium: rna secondary structure and regulation of termination. | transcription termination at the attenuators of the trp operons of escherichia coli and salmonella typhimurium was studied in vitro using dna restriction fragments as templates. readthrough transcription beyond the terminators occurred with 5 and 30% efficiency, respectively, in e. coli and s. typhimurium. this difference is correlated with the stability of proposed secondary structures of the respective trp leader transcripts. secondary structure analyses of the two leader transcripts revealed ... | 1977 | 337297 |
| identification of the sid outer membrane receptor protein in salmonella typhimurium sl1027. | a protein of molecular weight 78,000 daltons, missing in albomycin and phage es18 resistant mutants, has been identified in the outer membrane of salmonella typhimurium sl1027. mutants with a tonb like resistance and over production of outer membrane proteins due to iron shortage were also isolated. the mutation which leads to the protein deficiency maps in the sid gene region, the mutation related to overproduction of proteins maps near trp. although the s. typhimurium and the e. coli protein m ... | 1977 | 337132 |
| genetic studies of hybrids between coliphage lambda and salmonella phage p22: genetic analysis of the p22-lambda hybrid class. | p22-lambda hybrids which retain the protein coat of p22 have been isolated and characterized into two types. type 1 hybrids which have the c through o-p genes of lambda are unable to grow lytically on salmonella typhimurium. on the other hand, type 2 hybrids which contain only the c region of lambda, plated on s. typhimurium. both hybrid types retained the generalized transducing and antigenic conversion capabilities of p22. | 1977 | 337122 |
| the utilization of pentoses and pentitols by different biotypes of salmonella typhimurium. | 1977 | 336843 | |
| a salmonella typhimurium endonuclease that converts native dna to fragments of about 8 x 10(5) daltons. | crude extracts of salmonella typhimurium were found to contain an endonuclease that degraded double-stranded linear dna from bacteria and phages to fragments with a molecular weight of about 8 x 10(5). the nuclease did not have an absolute requirement for mg2+. one discrete intermediate product had a molecular weight of 6-6 x 10(6). extracts from two different mutants were tested: one completely lacked the endonuclease activity (strain db5575), and the other showed an absolute requirement for mg ... | 1977 | 336842 |
| clonal distribution of resistance plasmid-carrying salmonella typhimurium, mainly in the middle east. | strains of salmonella typhimurium of predominantly middle eastern origin, but distributed from england to india, were found to carry at least three types of resistance plasmid. the most important was initially identified as an f(i) plasmid by compatibility tests, but differs from the f factor on the one hand and the f(i) factors r162 and colv on the other. the three groups of f(i) plasmids can be distinguished by their compatibility reactions with the mp10 plasmid of s. typhimurium (smith, humph ... | 1977 | 336792 |
| effects of antibiotics on the survival of salmonella in the american cockroach. | the faecal survival of salmonella typhimurium orally administered to restrained american cockroaches maintained on an antibiotic diet was investigated. significant reductions in median numbers of total aerobic faecal microorganisms were noted in insects fed antibiotics daily, and when salmonella was introduced to this modified micro-environment, it persisted for 44 days in all specimens. multiplication of the pathogen was also observed in these insects, with numbers often exceeding 10(3) times t ... | 1977 | 336789 |
| survival of salmonella eastbourne and salmonella typhimurium in milk chocolate prepared with artificially contaminated milk powder. | milk chocolate mass containing salmonellas was prepared by mixing artificially contaminated milk powder with the other ingredients at a temperature of about 40 degrees c. from this mass bars were made. two series were prepared, with s. eastbourne and s. typhimurium respectively. the number of surviving salmonellas was counted after various periods of storage, up to 19 months. s. eastbourne was reduced in numbers during 19 months from an initial count of ca. 3 x 10(4) to ca. 3 x 10(2) per 100 g o ... | 1977 | 336788 |
| salmonella-associated conjunctivitis in a cat. | salmonella typhimurium-associated conjunctivitis in an adult female cat was characterized by epiphora and blepharospasm. the cat also harbored intestinal s typhimurium, as did one other cat in the same shipment of 7 cats obtained from a commercial cat dealer. the 3 isolates were resistant to ampicillin, cephaloridine, cephalothin, streptomycin, triple sulfonamides, and tetracycline. all 3 isolates were capable of transferring a part of the antibiotic resistance pattern to an escherichia coli k-1 ... | 1977 | 336590 |
| mouse virulence of salmonella typhimurium mutants deficient in two major outer membrane proteins. | the role of several outer membrane components as virulence factors is well established. we have now isolated spontaneous mutants and conjugational hybrids of smooth mouse virulent salmonella typhimurium deficient in two major outer-membrane proteins. the lack of the 34,000- and/or 36,000-dalton proteins was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. mutants and recombinants were then tested for their mouse virulence by intraperitoneal inoculation and were found to be ... | 1977 | 336546 |
| effect of some r factors on the sensitivity of rough enterobacteriaceae to human serum. | eight plasmids out of 26 tested confer partial serum resistance to escherichia coli k-12 strains (bhs character). four bhs+ plasmids were tested in a rough salmonella typhimurium host, and three conferred partial serum resistance to this host as well. plasmids representative of 19 different incompatibility groups were examined; the bhs+ property was found in some (but not all) representatives of groups n, o, s, t, w, and f'lac (fi), and there was no apparent association between other plasmid mar ... | 1977 | 336539 |
| liability to hydrophobic and charge interaction of smooth salmonella typhimurium 395 ms sensitized with anti-ms immunoglobulin g and complement. | sensitization of smooth salmonella typhimurium 395 ms bacteria with hyper-immune anti-ms immunoglobulin g (igg) antibodies increased the liability to hydrophobic interaction as assessed by the affinity for a column of octyl-sepharose. after sensitization, the material originally eluted with 1 m (nh4)so4 in a 0.01 m phosphate buffer (ph 6.8) was not desorbed until the ionic strength was reduced to nil, and 0.1% (vol/vol) triton x-100 in the 0.01 m phosphate buffer was used as eluant. furthermore, ... | 1977 | 336538 |
| effect of salmonella typhimurium on myoelectrical activity in the rabbit ileum. | 1978 | 336451 | |
| mutagenesis by 4-nitrobenzofurazans and furoxans. | 15 nitrobenzofurazans and 10 nitrobenzofuroxans synthesized primarily for testing as potential anti-rheumatic drugs were also tested for mutagenicity in salmonella typhimurium strains ta98 and ta100. the method used involved placing each compound in a "well" cut out of a plate of selective medium previously seeded with the appropriate tester strain, and then adding a rat liver microsome/cofactor mixture to one of the two wells on each plate. this method is considerably cheaper and more convenien ... | 1977 | 336231 |
| inhibitory effects of selenium on 1,2-dimethylhydrazine and methylazoxymethanol colon carcinogenesis: correlative studies on selenium effects on the mutagenicity and sister chromatid exchange rates of selected carcinogens. | selenium (se) inhibition of either the activation of test compounds and/or mutagenic events elicited by activated compounds is suggested by experimental rat assays, mutagenesis assays, and assays with human lymphocytes in culture. the colon tumor incidence in 1,2-dimethylhydrazine (dmh)-treated rats was reduced from 87% to 40% by 4 ppm se supplements in the drinking water. supplemental se decreased the total number of colon tumors induced by dmh more than three-fold and by methylazoxymethanol (m ... | 1977 | 336188 |
| complex medium toxicity to some dna repair-deficient strains of salmonella typhimurium. | the recovery of several strains of salmonella typhimurium lt-2 which had first been grown in minimal medium varies when the organisms are grown on minimal medium agar and complex medium agar. the strains tested included mutants with deficiencies in dna-repair systems (uvrb-and rec-), a deep rough (rfa-) mutant, and a double mutant carrying both the uvrb- and the rfa-mutation. the uvrb- and rec-mutations imparted sensitivity to complex medium agar. the rfa-mutation suppressed the sensitivity of t ... | 1977 | 336166 |
| transport of [14c]gly-pro in a proline peptidase mutant of salmonella typhimurium. | the transport of [14c]gly-pro was examined using a mutant of salmonella typhimurium (strain tn87) deficient in an x-pro dipeptidase and an x-pro-y iminopeptidase. the dipeptide was taken up by one saturable transport system having a km of 5.3-10(-7)m and a v of 1.4 nmol/mg dry wt cell per min. the uptake of gly-pro was not inhibited by amino acids or tripeptides and the transport system exhibited a rather broad side chain specificity for dipeptides. dipeptides containing hydrophobic residues wer ... | 1977 | 336092 |
| properties of the ames salmonella mutants lodged in the gastrointestinal tract of gnotobiotic rats. | an association of the histidine auxotroph of salmonella typhimurium (strain ta1538) within the gastrointestinal tract of otherwise germ-free sprague-dawley rats is maintained during observations for up to 7 months. the bacteria exceed concentrations of 10(7)/g in the forestomach and exceed concentrations of 10(8)/g in the lower bowel and feces. when carcinogens are ingested, the number of revertants in the feces increases. the ingestion of structurally related compounds which are not mutagenic t ... | 1977 | 335870 |
| mandelonitrile beta-glucuronide: synthesis and characterization. | mandelonitrile beta-glucuronide, the compound patented as laetrile, has been synthesized from rabbit liver uridine diphosphate-glucuronosyl transferase immobilized on beaded sepharose, has been analyzed by thin-layer chromatography, nuclear magnetic resonance, and gas chromatography-mass spectrometry, and has been tested for cytotoxicity and mutagenic activity with salmonella typhimurium strains ta 98 and ta 100. several commercial laetrile preparations contained no glucuronide; they contained a ... | 1977 | 335509 |
| spontaneous, ultraviolet and ionizing radiation mutagenesis in two auxotrophic strains of salmonella typhimurium carrying an r plasmid. | ultraviolet-induced, gamma-induced and spontaneous mutation yields were studied in two different auxotrophic strains of salmonella typhimurium in the presence and absence of the uv-protecting drug resistance transfer factor r-utrecht. one strain, carrying the hisc527 (amber) mutation, showed significantly increased spontaneous, uv- and gamma-induced mutability in the presence of the r-utrecht plasmid. the other strain, carrying the trpd1 mutation (thought to be a missense mutation), also showed ... | 1977 | 335234 |
| virulence of salmonella typhimurium harbored in the feces of carrier-dog for mice. | 1977 | 335142 | |
| enzymatic degradation of polygalacturonic acid by yersinia and klebsiella species in relation to clinical laboratory procedures. | as scored by several specified plating procedures, clinical and environmental strains of yersinia enterocolitica, yersinia pseudotuberculosis, and klebsiella pneumoniae "oxytocum" showed detectable, albeit generally weak, ability to digest polygalacturonic (pectic) acid. none of these bacterial strains had the vigorous and rapid pectolytic activity on these polygalacturonic acid-containing media that is typical of soft-rot erwinia species, although some of the oxytocum strains came fairly close. ... | 1977 | 334794 |
| sugar transport. a pleiotropic membrane mutant of salmonella typhimurium. | 1977 | 334769 | |
| periplasmic space in salmonella typhimurium and escherichia coli. | the volume of the periplasmic space in escherichia coli and salmonella typhimurium cells was measured. this space, in cells grown and collected under conditions routinely used in work with these bacteria, was shown to comprise from 20 to 40% of the total cell volume. further studies were conducted to determine the osmotic relationships between the periplasm, the external milieu, and the cytoplasm. results showed that there is a donnan equilibrium between the periplasm and the extracellular fluid ... | 1977 | 334768 |
| [salmonella typhimurium--test system for detecting the mutagenic activity of environmental pollutants. ii. mutagenic effect of heavy metal salts in an in vitro system with metabolic activation]. | mutagenic effect of zinc chloride on salmonella typhimurium strain was detected using in vitro metabolic activation system. cadmium chloride showed no significant mutagenic activity in the same system. it is recommended to use both in vitro and in vivo metabolic activation systems in mutagenicity testing of chemicals. | 1977 | 334635 |
| the separation and properties of two penicillin-binding proteins from salmonella typhimurium. | 1977 | 334539 | |
| mutagenicity studies with praziquantel, a new anthelmintic drug: tissue-, host-, and urine-mediated mutagenicity assays. | praziquantel, a new anthelmintic drug with activity against all species of schistosomes pathogenic to man, and against a wide range of cestodes, was tested for mutagenic potential. for the detection of both base substitutions and frameshift mutations, salmonella typhimurium ta 100 and ta 98 were used as tester strains. using the plate assay with and without added s-9, host-mediated assay and urine-mediated assay without and after incubation with beta-glucuronidase/arylsulfatase, no mutagenic act ... | 1977 | 334117 |
| an epidemic of salmonella typhimurium infection among aircraft passengers. | in february 1976 an outbreak of gastroenteritis occurred among 819 aircraft passengers to and from gran canaria. 360 of them had gastroenteritis and 88 were hospitalized. fecal specimens were collected from 710 of the passengers and 344 of them were positive for salmonella typhimurium phage type 15. food served on the flight was the source of infection. the repeated incidences of this kind support the necessity of laying down rules and recommendations for the control of air catering services. | 1977 | 333553 |
| salmonella typhimurium arthritis in rheumatoid disease. | septic arthritis is a well recognized complication of rheumatoid arthritis (british medical journal, 1976; mitchell et al., 1976), particularly after joint replacement (freeman, 1976). we report here infection with an unusual organism--salmonella typhimurium. | 1977 | 333539 |
| mutagenicity of fungal metabolites related to aflatoxin biosynthesis. | fungal metabolites identified as the intermediates in aflatoxin biosynthetic pathway were screened for their mutagenic activity to salmonella typhimurium ta98. norsolorinic acid, averufin, and versiconal acetate were found to possess questionable mutagenic activity, but versicolorin a, and sterigmatocystin were significant mutagens relative to aflatoxin b1. the mutagenic activity appears to be related to the bisfuran and not the anthraquinone moiety of the molecule, even though the latter is a k ... | 1977 | 333283 |
| mutagenicity of isomeric diol-epoxides of benzo[a]pyrene and benz[a]anthracene in s. typhimurium ta98 and ta100 and in v79 chinese hamster cells. | pairs of isomeric vicinal diol-epoxides derived from benzo[a]pyrene 7,8- and 9,10-dihydrodiols and from benz[a]anthracene 8,9-dihydrodiol were tested for their abilities to revert salmonella typhimurium strains ta98 and ta100 to histidine prototrophy and to induce the formation of 8-azaguanine- or of ouabain-resistant v79 chinese hamster cells. all six diol-epoxides were active in both bacterial strains, but 7beta,8alpha-dihydroxy-9beta,10beta-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (the syn iso ... | 1977 | 333280 |
| frameshift mutagenesis in bacteria by 8-methoxypsoralen (methoxalen) in the dark. | we confirm that 8-methoxypsoralen (8-mop) in the dark induces frameshift mutations in both escherichia coli and salmonella typhimurium when present in adequate concentration under growth conditions. the dose response is sigmoidal with a threshold or quasi-threshold at concentrations below about 10 microgram/ml. frameshift mutagenesis by 8-mop in the dark is unaffected by mutations at the uvra or uvrb genes, in contrast to base pair substitution mutagenesis by 8-mop plus near uv light. reca (but ... | 1977 | 333279 |
| translocation of phospholipids between the outer and inner membranes of salmonella typhimurium. | the reversibility and specificity of phospholipid translocation between the inner and outer membrane of salmonella typhimurium has been investigated by incorporating exogenous lipids from phospholipid vesicles into the outer membrane of intact cells. translocation of newly incorporated phospholipids to the inner membrane was demonstrated by decarboxylation of vesicle-derived phosphatidylserine and by recovery of vesicle constituents in both inner and outer membrane fractions. all salmonella phos ... | 1977 | 332696 |
| interaction of salmonella typhimurium with phospholipid vesicles. incorporation of exogenous lipids into intact cells. | incubation of intact cells of salmonella typhimurium with bilayer phospholipid vesicles results in significant transfer of vesicle lipids to the cells. the transfer requires ca2+ or spermine, and is dependent on time, temperature, the concentration and composition of the vesicles, and the nature of the cellular lipopolysaccharide. the process results in bulk transfer of vesicle lipids to the cells rather than reciprocal molecular exchange between vesicles and the outer membrane. all components o ... | 1977 | 332695 |
| interactions between salmonellae and macrophages of guinea pigs. iv. relationship between migration inhibition and antibacterial action of macrophages. | the in vitro macrophage migration inhibition test was used to detect the development of delayed-type hypersensitivity in guinea pigs infected with salmonella typhimurium. four different preparations from supernatants of s. typhimurium cultures were used as the antigens in this test. they included the concentrated bacterial antigens, the high-molecular-weight (>50,000) antigens, the ammonium sulfate-precipitated antigens, and the ribonuclease-treated antigens. all four antigen preparations were s ... | 1977 | 332643 |
| increased resistance of iron-deficient mice to salmonella infection. | nutritional iron deficiency in mice attenuated salmonella typhimurium infection compared with both iron-substituted littermates and normal diet control animals. | 1977 | 332634 |
| [salmonella typhimurium as a test system for detecting the mutagenic activity of environmental pollutants. i. the mutagenic action of heavy metal salts in in vivo and in vitro systems without metabolic activation]. | the work presents the data on mutagenic effects of heavy metal salts (zn and cd) on salmonella typhimurium test strains using mutagenicity test in vitro without metabolic activation and host-mediated assay. the techniques used enabled to determine also the types of mutations arising from the exposure to zncl2 and cdcl2. | 1977 | 332590 |
| mutagenicity of 3a,8a-dihydrofuro[2,3-b]benzofuran, a model of aflatoxin b1, for salmonella typhimurium ta100. | 1977 | 332158 | |
| [change in the protective activity of the ribosomal fractions of salmonella typhimurium in mutations in the rfa region and the transduction replacement of the rfb region]. | it was shown that mutation in the rfa region causing disturbances in the structure of the basal part of the polysaccharide of the cell wall or the absence of o-specific side chains led to the loss of protective activity of the ribosomal fractions isolated from the cells of the murine typhoid salmonella by sedimentation with dihydrostreptomycine sulphate. ribosomal fractions isolated from the murine typhoid salmonella transductants with the replaced rfb region failed to protect the animals from t ... | 1977 | 331765 |
| mutagenicity and cytotoxicity of benz[alpha]anthracene diol epoxides and tetrahydro-epoxides: exceptional activity of the bay region 1,2-epoxides. | three diastereomeric pairs of diol epoxides, two tetrahydro-epoxides, and the k-region oxide of the polycyclic aromatic hydrocarbon benz[a]anthracene were evaluated for mutagenic activity in strain ta 100 of salmonella typhimurium and in line v79-6 of chinese hamster lung cells. the two diastereomeric 1,2-epoxides of the trans-3,4-dihydrodiol of benz[a]anthracene are 15 to 35 times more mutagenic to the bacteria and 65 to 125 times more mutagenic to the mammalian cells than are the diastereomeri ... | 1977 | 331315 |
| biosynthesis of trna in histidine regulatory mutants of salmonella typhimurium. | hisu mutants of salmonella typhimurium are depressed in the histidine operon since they have lower intracellular concentration of histidyl-trnahis. in this paper we present evidences showing that a strain carrying a hisu mutation (hisul206) is altered in a nucleolytic enzyme involved in trna maturation process. the analysis of several hisu mutants indicates that hisu region of bacterial genome may account for more than one function involved in trna biosynthesis. | 1977 | 331266 |
| a study of the photoinduced mutagenicity of methylene blue. | illumination of salmonella typhimurium strains in the presence of methylene blue resulted in the production of mutations of the base-substitution type. this photodynamic effect mediated by the dye was separable from the genetic event seen when bacteria are illuminated in the absence of added photosensitizers. | 1977 | 331101 |
| testing of some azo dyes and their reduction products for mutagenicity using salmonella typhimurium ta 1538. | a series of ten azo dyes as well as various single ring aromatic amines substituted on the benzene ring were tested for bacterial mutagenicity with salmonella typhimurium ta 1538 using a soft-agar overlay method. two dyes, sudan 2 and chrysoidin induced mutation but only in the presence of a rat liver preparation. chrysoidin was the more active. testing of its reduction products, aniline and 1,2,4-triaminobenzene showed a liver metabolite of the latter compound could be responsible for the mutag ... | 1977 | 331098 |
| dna degradation in wild-type and repair-deficient strains of salmonella typhimurium exposed to ultraviolet light of photodynamic treatment. | five mutants of salmonella typhimurium strain lt2 trp di (colei)+, initiallly detected because they released little or no colicin when tested on solid medium, proved to be sensitive to ultraviotet light (u.v.). further testing indicated that one of the mutants was deficient in genetic recombination and was probably a reca-type mutant, while three of the others were deficient in dna polymerase activity and appeared to be typical pola mutants. the fifth mutant was less sensitive than the others to ... | 1977 | 330821 |
| infection of hela cells with salmonella typhimurium 395 ms and mr10 bacteria. | after interaction with hela cells cultured in vitro, the fraction of adhering extracellular and that of internalized smooth salmonella typhimurium 395 ms and rough 395 mr10 have been determined by two different techniques. (i) by using the indirect fluorescent-antibody technique on unfixed and acetone-fixed hela cell preparations, intracellular bacteria were considered to become stained only after acetone fixation. (ii) based on the assumption that gentamicin affects only extracellular bacteria, ... | 1977 | 330403 |
| a comparison of the amino-terminal sequences of several carbohydrate binding proteins from escherichia coli and salmonella typhimurium. | 1977 | 330247 | |
| in vitro mutagenicity of the soil nematicide 1,3-dichloropropene. | the cis- and trans-isomers of 1,3-dichloropropene have been tested in the ames mutagenicity assay system on salmonella typhimurium tester strain ta 1535. both isomers have been found to be mutagenic even without microsomal activation. | 1977 | 330205 |
| humoral response to salmonella typhimurium antigens in normal and thymectomized urodele amphibian pleurodeles waltlii michah. | 1977 | 330172 | |
| transfer of episome f'lac+ and chromosomal trp+ genes from erwinia amylovora to salmonella typhimurium. | the f'lac+ episome of escherichia coli origin was transferred by conjugation with frequencies of 10(-7) to 10(-5) from erwinia amylovora to 14 out of 15 salmonella typhimurium trp female parents. the chromosomal trp+ genes were transferred with frequencies of 10(-7) to 10(-6) only to one trpb and 2 trpd female parents, which have a point mutation in the 2nd and fourth structural genes, respectively, of the tryptophan operon. the transferred male trp+ genes became integrated at the selected sites ... | 1977 | 330120 |
| mutagenicity of smoke condensates from cigarettes, cigars and pipe tobacco. | smoke condensates from cigarettes, cigars and pipe tobacco were mutagenic on salmonella typhimurium ta100 and ta98 when activated with rat liver microsomal system. mutagenicity of a unit weight of smoke condensate was rather high in cigars, low in pipe tobacco and intermediate in cigarettes. specific mutagenic activity was almost comparable among smoke condensates from low- to high-tar cigarettes, although some variations were observed depending upon the country producing the cigarettes. marked ... | 1977 | 329976 |
| histidinol dehydrogenase from salmonella typhimurium and escherichia coli. purification, some characteristics and the amino acid sequence around a reactive thiol group. | the purification and some physical properties of histidinol dehydrogenase, l-histidinol-nicotinamide adenine dinucleotide oxido-reductase (ec 1.1.1.23) from either salmonella typhimurium or escherichia coli are reported in this paper. modification of histidinol dehydrogenase with one equivalent of n-(4-dimethylamino-3,5-dinitrophenyl)maleimide at ph 6.8 yields an enzyme that is inactive toward the oxidation of l-histidinol. the modified cysteine residue was located in an acid insoluble tryptic c ... | 1977 | 329890 |
| nutritional effects of salmonellosis in mice. | mice infected with a standard challenge of salmonella typhimurium manifest a number of changes associated with endotoxemia. these changes result in profound alterations in the nutritional and metabolic status of the host. food and water intake approaches levels of total inanition, blood glucose declines more rapidly than in fasted controls, hepatic phosphoenolpyruvate carboxykinase (the enzyme that is rate limiting in gluconeogenesis) shows diminished activity and loss of cortisol inducibility, ... | 1977 | 329666 |
| the tendency of smooth and rough salmonella typhimurium bacteria and lipopolysaccharide to hydrophobic and ionic interaction, as studied in aqueous polymer two-phase systems. | in aqueous two-phase system, the partition of bacteria and lipopolysaccharide from a rough (r) strain (rd-mutant) of salmonella typhimurium is influenced by polymers with covalently linked hydrophobic groups indicating hydrophobic structures accessible at the cell surface. furthermore, the partition of the r bacteria is influenced by a number of inorganic positive and negative ions, presumably as a consequence of interaction with negatively charged surface structures. in contrast, smooth (s) bac ... | 1977 | 329639 |
| [salmonella typhimurium infection during systemic lupus erythematosus]. | 1977 | 329376 | |
| effect of mutant host rna polymerase on the bifunctional activities of p22 gene c1. | the product of phage p22 gene c1 has two functions: (1) it promotes synthesis of repressor and (2) during the first minutes of infection it retards expression of some lytic genes. we call the second, negative function "c1 retardation". we investigated c1 retardation in a mutant host of salmonella typhimurium that is resistant to rifampicin and carries an altered rna polymerase. no c1 retardation of dna synthesis was detectable in this host after infection with wild-type phages. this elimination ... | 1977 | 329118 |
| on the ability of salmonella typhimurium cells to form deoxycytidine nucleotides. | it is known that cdd- s. typhimurium mutants selected for resistance to 5-fluorodeoxycytidine (fdcyd) possess no deoxycytidine kinase activity. the present study postulates that this method of screening selects double mutants defective in cytidine deaminase and in deoxycytidine kinase. to prove this hypothesis, the cdd mutant of s. typhimurium was constructed by p1-mediated transfer of ccd- gene into a new genetic background, and the activity of deoxycytidine kinase was assayed. transductants ex ... | 1977 | 329115 |
| internal reinitiation of translation in polar mutants of the trpb gene of salmonella typhimurium. | 1977 | 329111 | |
| [salmonella typhimurium isolated from the spinal fluid of 2 children]. | in this article isolation of s. typhimurium bacteria from cebrospinal fluid of two children is reported. | 1977 | 329073 |
| physicochemical consequences of opsonization: perturbation of liposomal membranes by salmonella typhimurium 395 ms opsonized with igg antibodies. | when phagocytosis-resistant salmonella typhimurium 395 ms bacteria sensitized with anti-ms igg antibodies were incubated with liposomes composed of phosphatidylcholine, cholesterol, and dicetylphosphate, a previously sequestered liposomal marker (4-methylumbelliferylphosphate) was released. unsensitized or f(ab')2-sensitized bacteria had no such effect. this perturbation was neither dependent upon negatively charged dicetylphosphate nor upon cholesterol. it was further evident that palmitoyl-pol ... | 1977 | 328778 |
| the immunization of mice and calves with gal e mutants of salmonella typhimurium. | a galactose epimeraseless (gal e) mutant of salmonella typhimurium was investigated in mice and calves for its suitability as a live vaccine. in mice, a very highly significant difference in the mortality rates was observed when vaccinated and non-vaccinated animals were challenged with virulent strains of s. typhimurium and s. dublin. in calves, doses of 10(6) and above of gal e mutant injected subcutaneously provided highly significant protection both in terms of mortality and prevalence of sy ... | 1977 | 328767 |
| phosphoenolpyruvate:sugar phosphotransferase system in ancalomicrobium adetum. | ancalomicrobium adetum possesses a membrane-associated phosphoenolpyruvate:sugar phosphotransferase system, the components of which exhibited enzymatic cross-reactivity with those from salmonella typhimurium. | 1977 | 328495 |
| role of endotoxin contamination in ribiosomal vaccines prepared from salmonella typhimurium. | ribosomal vaccines prepared from salmonella typhimurium sr-11 and 6707 an re mutant bacterium of strain lt2, were effective immunogens in a/j and c3h/hedub inbred mice. only sr-11 ribosomes were able to induce significant protection in c3h/hej mice. c57bl/6j mice were not protected by either ribosomal preparation. a/j mice were protected against salmonella infection by purified sr-11 endotoxin preparations. neither the c3h/hedub, the c3h/hej, nor the c57bl/6j mice were protected by the endotoxin ... | 1977 | 328399 |
| ochre suppression in salmonella typhimurium. | a bacterial strain was constructed which permitted positive selection for ochre suppressor mutations as well as for the loss of suppressor function. a derivative bearing an ochre suppressor mutation was selected following mutagenesis with n-methyl-n-nitroso-n'-nitroguanidine. the suppressor-bearing strain was treated with nitrous acid to eliminate suppressor function by mutation, and a strain lacking suppressor activity was selected. the selected strain which had lost suppressor function was the ... | 1977 | 328342 |
| isolation of mutants conditionally blocked in the biosynthesis of the 3-deoxy-d-manno-octulosonic-acid--lipid-a part of lipopolysaccharides derived from salmonella typhimurium. | a procedure is described for the selection of conditional 3-deoxy-d-manno-octulosonic-acid--lipid a mutants which depends on temperature sensitivity for both synthesis of complete lipopolysaccharide and for growth. using this procedure new types of mutants were isolated which cease growth and accumulate lipid a precursors following a shift to nonpermissive temperatures. all precursor molecules differ in their charge as judged by deae-cellulose chromatography. while they all contain glucosamine, ... | 1977 | 328282 |
| mutagenicity testing of styrene and styrene epoxide in salmonella typhimurium. | 1977 | 328090 | |
| stereoselectivity and stereospecificity of the alpha,beta-dihydroxyacid dehydratase from salmonella typhimurium. | 1. in addition to the known 2r,3r- and 2r, 3s-2,3-dihydroxy-3-methylpentanoic acids (dhi), the 1s,3s- and ss,dr-isomers were prepared. 2s-2,3-dihydroxy-3-methylbutanoic acid (dhv) was also prepared in addition to the known 2r-isomer. 2. the six dihydroxy acids were examined for their ability to promote the growth of isoleucine-valine (ilv)-requiring strains of salmonella typhimurium and to serve as substrates for the alpha,beta-dihydroxyacid dehydratase of the same organism. 3. only 2r,3r-2,3-di ... | 1977 | 328058 |
| beta-lactamase-directed barrier for penicillins of escherichia coli carrying r plasmids. | strains of escherichia coli and salmonella typhimurium carrying r plasmids, which were obtained from ampicillin-resistant clinical isolates of e. coli and klebsiella spp. and specified either the type iiia (tem-type) or type va (oxacillin-hydrolyzing) beta-lactamase, are resistant not only to ampicillin but also to carbenicillin and sulbenicillin. the latter two derivatives, however, are poorly hydrolyzed in vitro by the beta-lactamases. although values of k(m) of the enzymes are lower for sulbe ... | 1977 | 327924 |
| r factor types found in salmonella typhimurium and escherichia coli isolated from calves in a confined environment. | typing of r factors by genetic properties was done with salmonella typhimurium and escherichia coli isolated from calves on a feedlot where epizootics of clinical or subclinical calf salmonellosis had repeatedly occurred during 5 years. forty-nine r factors from s typhimurium were fi- (no fertility inhibition) and spp- (no restriction against phage lambda vir). twenty-three (46.9%) of them belonged to compatibility group ialpha and the remainder were nontypable. fourteen r factors from e coli be ... | 1977 | 327875 |
| mutagenic activity of quercetin and related compounds. | the mutagenic activities of several flavonoids and flavonoid metabolites were examined by means of salmonella typhimurium mutants that reveal base-pair substitution and frameshift mutagens. of the compounds tested (naringin, rutin, neohesperetin, hesperetin, dihydroquercetin, quercetin, quercetin pentaacetate, permethylquercetin, m-hydroxyphenylacetic acid, and m,p-dihydroxyphenylacetic acid), only quercetin was mutagenic without microsomal activation. with activation, however, the mutagenic act ... | 1977 | 327550 |
| relation between chemical constituents of tobacco and mutagenic activity of cigarette smoke condensate. | mutagenic activities of cigarette smoke condensate were assayed in the presence of s-9 mix using salmonella typhimurium ta 98. the results were examined in relation to chemical data of tobacco leaves. among the nitrogenous constituents examined, the contents of total nitrogen and protein nitrogen and the soluble nitrogenous fraction were positively and significantly related to an increase in mutagenic activity of the smoke condensate, whereas nicotine and nitrate were not important in contributi ... | 1977 | 327316 |
| mutagenicity of nitrovin--a nitrofuran feed additive. | nitrovin, a nitrofuran feed additive, is shown to be directly mutagenic in salmonella typhimurium ta 98 and ta 100 between 0.1 and 2.5 microgram per plate (0.09--2.3 micrometer). addition of a rat-liver homogenate reduces the mutation rates. nitrovin inhibits growth of the same bacteria in suspension cultures at concentrations above 0.09 micrometer. | 1977 | 327315 |