| cross-reactive proteins of borrelia burgdorferi. | the specificity of serological tests for lyme borreliosis is impaired by cross-reacting antibodies. in order to select antigens for more specific tests, specific and cross-reactive proteins of borrelia burgdorferi must be identified. therefore, to analyze cross reactions of borrelia burgdorferi with other bacteria, rabbit immune sera against heterologous bacteria (borrelia hermsii, treponema pallidum, treponema phagedenis, leptospira interrogans (serogroup grippotyphosa), neisseria meningitidis, ... | 1992 | 1597198 |
| augmentation of host resistance to listeria monocytogenes infection by a traditional chinese medicine, ren-shen-yang-rong-tang (japanese name: ninjin-youei-to). | ren-shen-yang-rong-tang (japanese name: ninjin-youei-to, nin), a traditional chinese medicine, is a drug made of spray-dried powder of hot water extract obtained from twelve species of medical plants. an intraperitoneal (ip) injection with nin 2 days before intravenous (iv) infection with listeria monocytogenes (l. monocytogenes) accelerated elimination of viable bacteria in the spleen in the early stage of infection (from day 1) and protected mice from the lethal infection. it was suggested tha ... | 1992 | 1597654 |
| identification of the bactericidal domain of lactoferrin. | we report the existence of a previously unknown antimicrobial domain near the n-terminus of lactoferrin in a region distinct from its iron-binding sites. a single active peptide representing this domain was isolated following gastric pepsin cleavage of human lactoferrin, and bovine lactoferrin, and sequenced by automated edman degradation. the antimicrobial sequence was found to consist mainly of a loop of 18 amino acid residues formed by a disulfide bond between cysteine residues 20 and 37 of h ... | 1992 | 1599934 |
| administration of anti-il-4 monoclonal antibody 11b11 increases the resistance of mice to listeria monocytogenes infection. | the role of endogenous il-4 in resistance to listeria monocytogenes infection was investigated by in vivo administration of an anti-il-4 mab (11b11). mice treated with 0.01 to 0.4 mg of anti-il-4 mab before l. monocytogenes challenge demonstrated a significantly reduced peak bacterial burden in their livers and spleens and accelerated bacterial clearance from these organs. in addition, histopathologic damage to the liver was reduced. maximal protection was achieved by i.p. injection of 0.1 mg of ... | 1992 | 1602140 |
| feto-maternal listeriosis in denmark 1981-1988. | we collected clinical information about 30 cases of listeria monocytogenes infections in pregnancy, which occurred in denmark between 1981 and 1988. the incidence of feto-maternal listeriosis was approximately one case per 100,000 live births in the early 1980s but increased to 25.3 cases per 100,000 live births in 1986. listeriosis in denmark occurred in two different patterns: endemic, in which the feto-maternal cases were a small proportion of the total, and epidemic: cases due to strains whi ... | 1992 | 1602149 |
| fatal septicaemia due to listeria monocytogenes in a patient with systemic lupus erythematosus receiving cyclosporin and high prednisone doses. | cyclosporin a is widely used in organ transplantation, preventing the rejection of multiple types of organ allografts. it is also being increasingly used as an immunosuppressive agent to treat various autoimmune diseases in patients refractory to more commonly used immunosuppressive therapy. several trials are currently evaluating the utility of this drug associated with corticosteroids in the treatment of systemic lupus erythematosus. this case, describing a lethal septicaemia caused by listeri ... | 1992 | 1603211 |
| genetic basis of tetracycline resistance in clinical isolates of listeria monocytogenes. | the genetic basis of tetracycline resistance was studied in 25 clinical isolates of listeria monocytogenes. resistance to tetracycline was associated with resistance to minocycline and due to the presence of the tet(m) gene in 24 strains. association of tet(m) with int-tn, the gene encoding the protein required for the movements of tn1545-like conjugative transposons, was found in all strains. cotransfer of tet(m) and int-tn among l. monocytogenes cells and from l. monocytogenes to enterococcus ... | 1992 | 1605611 |
| effect of macrophage activation on killing of listeria monocytogenes. roles of reactive oxygen or nitrogen intermediates, rate of phagocytosis, and retention of bacteria in endosomes. | the role of macrophage activation in the killing of l. monocytogenes is unclear. some studies suggest that activation for enhanced production of reactive oxygen and nitrogen intermediates may not be of central importance. recent data have indicated an important role for interferon-gamma (ifn-gamma) induced retention of l. monocytogenes in endosomes. data from the present study indicate that proteose peptone-elicited macrophages from dba2/j, cd-1, and c3h/hen mice are listericidal. activation of ... | 1992 | 1606735 |
| induction of a cellular immune response to a foreign antigen by a recombinant listeria monocytogenes vaccine. | a recombinant strain of listeria monocytogenes that stably and constitutively expresses escherichia coli beta-galactosidase was used as a live vaccine vector. balb/c mice were immunized orally or parenterally with the recombinant l. monocytogenes, and their cellular and humoral immune responses to beta-galactosidase were measured. spleen cells taken 1 week after oral inoculation or 5 weeks after oral or parenteral inoculation (with a boost at 4 weeks) showed beta-galactosidase-specific ctl respo ... | 1992 | 1607662 |
| from the food and drug administration. | | 1992 | 1608124 |
| novel form of growth cone motility involving site-directed actin filament assembly. | regulation of cytoskeletal structure and motility by extracellular signals is essential for all directed forms of cell movement and underlies the developmental process of axonal guidance in neuronal growth cones. interaction with polycationic microbeads can trigger morphogenic changes in neurons and muscle cells normally associated with formation of pre- and postsynaptic specializations. furthermore, when various types of microscopic particles are applied to the lamellar surface of a neuronal gr ... | 1992 | 1608453 |
| inhibition of listeria monocytogenes by fatty acids and monoglycerides. | fatty acids and monoglycerides were evaluated in brain heart infusion broth and in milk for antimicrobial activity against the scott a strain of listeria monocytogenes. c12:0, c18:3, and glyceryl monolaurate (monolaurin) had the strongest activity in brain heart infusion broth and were bactericidal at 10 to 20 micrograms/ml, whereas potassium (k)-conjugated linoleic acids and c18:2 were bactericidal at 50 to 200 micrograms/ml. c14:0, c16:0, c18:0, c18:1, glyceryl monomyristate, and glyceryl mono ... | 1992 | 1610184 |
| differentiation of listeria monocytogenes, listeria innocua, listeria ivanovii, and listeria seeligeri by pulsed-field gel electrophoresis. | clamped homogeneous electric field analysis of listeria dna with apai, asci, smai, or noti revealed species- and serotype-specific differences in genomic fingerprints. clamped homogeneous electric field analysis may prove useful, therefore, in epidemiologic studies. also, the summation of individually sized asci fragments of genomic dna from l. monocytogenes serotype 4b 101m and scott a indicated genome lengths of 2,925 and 3,046 kb, respectively. | 1992 | 1610193 |
| suitability of the prfa gene, which encodes a regulator of virulence genes in listeria monocytogenes, in the identification of pathogenic listeria spp. | the pathogenesis of listerial infections is complex and involves a number of virulence factors expressed by virulent listeria species. we have recently described a regulator gene, prfa, that positively regulates the expression of a number of virulence factors in listeria monocytogenes. when the prfa gene was used as a dna probe, we found it to be extremely specific for the pathogenic species l. monocytogenes. no reaction was obtained with strains of all other species of this genus. by using this ... | 1992 | 1610204 |
| l. monocytogenes oligonucleotide probe. | | 1992 | 1610206 |
| delayed type hypersensitivity (dth): studies on necrotising dth-reactions against listerial antigen in the skin of guinea pigs. | delayed type hypersensitivity (dth) to facultative intracellular bacteria which leads to destructive skin reactions was so far only investigated against mycobacterial antigens in guinea pigs whereas this work investigates destructive dth-reactions in the skin of guinea pigs which are directed against listerial antigens. toxic factors of viable listerias induced an enhancement of destructive skin reactions in non-immunised guinea pigs as compared to immunised ones. in contrast, heat killed lister ... | 1992 | 1611210 |
| effects of administration of murine recombinant il-4 on the resistance of mice to listeria monocytogenes infection. | mice given recombinant murine interleukin-4 as a single i.v. bolus concomitant with a listeria monocytogenes challenge did not display increased anti-listeria resistance. under certain conditions, il-4 administration slightly increased the bacterial burdens in the spleens and livers of infected mice. this finding is consistent with previous reports that endogenous il-4, or transfer of il-4 producing th2 cells, can be detrimental to host defense against microbial infection. | 1992 | 1612642 |
| capacity of listeriolysin o, streptolysin o, and perfringolysin o to mediate growth of bacillus subtilis within mammalian cells. | the listeria monocytogenes hemolysin listeriolysin o (llo) plays a major role in mediating the escape of l. monocytogenes from a vacuolar compartment. in a previous report, it was shown that bacillus subtilis expressing llo could escape from a host vacuolar compartment and grow in the cytoplasm (j. bielecki, p. youngman, p. connelly, and d. a. portnoy, nature [london] 345:175-176, 1990). in the present study, two related thiol-activated hemolysins, streptolysin o (slo) and perfringolysin o (pfo) ... | 1992 | 1612739 |
| review of the in vitro antibacterial activity of cefprozil, a new oral cephalosporin. | cefprozil is a newer oral cephalosporin with a spectrum of activity against organisms that include gram-positive and gram-negative pathogens. a review of published data shows that cefprozil is active (susceptibility, less than or equal to 8 micrograms/ml; moderate susceptibility, 16 micrograms/ml; resistance, greater than or equal to 32 micrograms/ml) against gram-positive species such as streptococci, methicillin-susceptible staphylococci, and listeria monocytogenes; it may have marginal activi ... | 1992 | 1617037 |
| how listeria exploits host cell actin to form its own cytoskeleton. i. formation of a tail and how that tail might be involved in movement. | after listeria is phagocytosed by a macrophage, it dissolves the phagosomal membrane and enters the cytoplasm. the listeria then nucleates actin filaments from its surface. these actin filaments rearrange to form a tail with which the listeria moves to the macrophage surface as a prelude to spreading. since individual actin filaments appear to remain in their same positions in the tail in vitro after extraction with detergent, the component filaments must be cross-bridged together. from careful ... | 1992 | 1618908 |
| how listeria exploits host cell actin to form its own cytoskeleton. ii. nucleation, actin filament polarity, filament assembly, and evidence for a pointed end capper. | after listeria, a bacterium, is phagocytosed by a macrophage, it dissolves the phagosomal membrane and enters the cytoplasm. the listeria than nucleates actin filaments from its surface. these newly assembled actin filaments show unidirectional polarity with their barbed ends associated with the surface of the listeria. using actin concentrations below the pointed end critical concentration we find that filament elongation must be occurring by monomers adding to the barbed ends, the ends associa ... | 1992 | 1618909 |
| [listeria monocytogenes: the cause of cholangitis in a liver transplant?]. | | 1992 | 1620950 |
| hemolytic interactions of dermatophilus congolensis. | the strains of dermatophilus congolensis grew on blood agar with washed sheep erythrocytes with marked total hemolysis. in testing for hemolytic interactions they gave a significant synergistic effect of a characteristic shape with rhodococcus equi and streptococcus agalactiae, whereas with staphylococcus aureus producing beta hemolysin and with staphylococcus aureus producing delta hemolysin a simultaneous synergistic as well as antagonistic effect were observed. first of all a conspicuous inhi ... | 1992 | 1621476 |
| use of polymerase chain reaction for detection of listeria monocytogenes in food. | a previously described polymerase chain reaction (pcr) assay (b. furrer, u. candrian, c. höfelein, and j. lüthy, j. appl. bacteriol. 70:372-379, 1991) was used to analyze food for the presence of listeria monocytogenes. food samples were artificially contaminated to develop two procedures to detect the organism following enrichment steps. procedure a was based on dilution of the enrichment broth followed by lysis of the bacteria and direct analysis of the lysate with pcr. with procedure a and ar ... | 1992 | 1622226 |
| api listeria, a new and promising one-day system to identify listeria isolates. | api listeria is a new 10-test strip for 24-h biochemical identification of listeria isolates. with this commercial system, 85% of 646 listeria strains, including atypical isolates selected for this study, were recognized at the species and subspecies level without a complementary test. a new test differentiates listeria monocytogenes from l. innocua on the basis of the absence of arylamidase from the former. with this system, 97.7% (252 of 258) of the l. monocytogenes strains tested were correct ... | 1992 | 1622261 |
| monoclonal antibody specific for listeria monocytogenes associated with a 66-kilodalton cell surface antigen. | a monoclonal antibody (mab), em-7g1, specific for listeria monocytogenes was developed by using a previously developed mab, c11e9 (a. k. bhunia, p. h. ball, a. t. fuad, b. w. kurz, j. w. emerson, and m. g. johnson, infect. immun. 59:3176-3184, 1991), to mask epitopes shared by l. monocytogenes and listeria innocua in a 66-kda cell surface protein. mab em-7g1 was an immunoglobulin subclass g1 antibody with kappa light chains. this mab reacted with all 34 strains of l. monocytogenes tested and sho ... | 1992 | 1622267 |
| thermotolerance of heat-shocked listeria monocytogenes in milk exposed to high-temperature, short-time pasteurization. | the effect of prior heat shock (48 degrees c for 15 min) on the thermotolerance of listeria monocytogenes at the minimal high-temperature, short-time (71.7 degrees c for 15 s) parameters required by the pasteurized milk ordinance was examined. the mean d71.7 degrees c value for heat-shocked l. monocytogenes was 4.6 +/- 0.5 s (control d = 3.0 +/- 1.0 s); the ratio of d to control d was 1.5. the increased thermotolerance of heat-shocked listeria cells was not significant and appeared unlikely to h ... | 1992 | 1622288 |
| sites of action by propionate on listeria monocytogenes. | exposure of listeria monocytogenes to a solution of sodium propionate (8% w/v) for 60 min caused 87% of the population to be injured. injury was evidenced by inability of the bacterium to tolerate 6% sodium chloride in tryptose agar as compared to ability to grow on tryptose agar with no added salt. injured cells were allowed to repair in tryptose broth and the repair process was studied by addition to tryptose broth of sublethal amounts of metabolic or synthetic inhibitors. repair of injured ce ... | 1992 | 1622747 |
| characterisation of danish isolates of listeria monocytogenes by multilocus enzyme electrophoresis. | a total of 84 strains of listeria monocytogenes were analysed by multilocus enzyme electrophoresis at twelve enzyme loci. eight enzyme loci were polymorphic with between 2 and 4 alleles per locus. fourteen electrophoretic types (ets) were identified. among 62 human clinical isolates from denmark, 8 different ets were defined. two ets, designated et 1 and et 6, accounted for 77% of the human clinical isolates investigated. these ets are identical with those responsible for several epidemics in sw ... | 1992 | 1622759 |
| bioluminescent listeria monocytogenes provide a rapid assay for measuring biocide efficacy. | | 1992 | 1624105 |
| [results of studies with aborted cattle fetuses]. | the laboratory of the animal health service of south holland investigated 2410 cases of spontaneous abortion (twins (112) were considered one case). seventy-eight afterbirths without foetuses were also examined. the aim of the study was not only to find the cause of abortion but also to see whether there was a relation between the results of the different bacteriological, virological and histological tests used. the presence of igg in the blood of foetuses older than 5 months was also determined ... | 1992 | 1626316 |
| macroepidemiology of the hivs-aids (haids) pandemic. insufficiently considered zoological and geopolitical aspects. | the human immunodeficiency viruses (hivs)-acquired immunodeficiency syndrome (aids) or haids pandemic originated from lentiviruses of nonhuman primates (thus qualifying as a zoonosis) that moved into humans in africa. the haids patients eventually die of opportunistic infections, all potentially zoonotic. the haids infection remained parochial, first endemically and then epidemically, until the african urbanization that occurred in each of the countries postindependence. the latter included wars ... | 1992 | 1626879 |
| transfer of both protection and delayed-type hypersensitivity against live listeria is mediated by the cd8+ t cell subset: a study with listeria-specific t lymphocytes recovered from murine infected liver. | the recruitment of specific t lymphocytes in murine liver is thought to be a key event in the ultimate control of listeria monocytogenes growth during primary infection. however, there has been little functional characterization of the cell populations recruited in this non-lymphoid organ. therefore in this study, the recruited lymphomyeloid cells were isolated from the liver of c57bl/6 mice at the peak of the immune response (day 7) triggered by a non-lethal l.monocytogenes infection. the anti- ... | 1992 | 1627496 |
| a general method for cloning reca genes of gram-positive bacteria by polymerase chain reaction. | an internal fragment of the reca gene from eight gram-positive organisms has been amplified by using degenerate primers in a polymerase chain reaction. the internal 348- or 360-bp reca dna segments from bacillus subtilis, clostridium acetobutylicum, lactobacillus bulgaricus, lactobacillus helveticus, leuconostoc mesanteroides, listeria monocytogenes, staphylococcus aureus, and streptococcus salivarus subsp. thermophilus were amplified, cloned, and sequenced. the g + c contents of the dna from th ... | 1992 | 1629178 |
| [listeria monocytogenes in food]. | as in recent years laboratory diagnostics of listeria has become part of food microbiology, the frequency of occurrence of the bacteria listeria monocytogenes has been followed in various kinds of foods for a year. a total of 51 strains of l. monocytogenes (7.2%) was isolated from 700 kinds of samples (raw milk, pasteurized milk, meat surface, poultry, cheeses, thermally not treated meat products, food--industry machinery). as can be seen in tab. i, the highest number of strains was isolated fro ... | 1992 | 1632053 |
| depletion of proton motive force by nisin in listeria monocytogenes cells. | the basal proton motive force (pmf) levels and the influence of the bacteriocin nisin on the pmf were determined in listeria monocytogenes scott a. in the absence of nisin, the interconversion of the ph gradient (z delta ph) and the membrane potential (delta psi) led to the maintenance of a fairly constant pmf at -160 mv over the external ph range 5.5 to 7.0. the addition of nisin at concentrations of greater than or equal to 5 micrograms/ml completely dissipated pmf in cells at external ph valu ... | 1992 | 1637163 |
| listericidal and nonlistericidal mouse macrophages differ in complement receptor type 3-mediated phagocytosis of l. monocytogenes and in preventing escape of the bacteria into the cytoplasm. | listeria monocytogenes is a facultative intracellular bacterium that escapes phagocytic vesicles and replicates in the cytoplasm, where it becomes coated with f-actin. macrophages, important anti-listeria effector cells, are heterogeneous in their ability to kill listeria. complement receptor type 3 (cr3) mediates most phagocytosis of listeria by listericidal macrophages. experiments described here tested whether nonlistericidal macrophages also phagocytosed listeria through cr3 and whether the ... | 1992 | 1640177 |
| altered host resistance to listeria monocytogenes in mice exposed to 1-chloroacetophenone (cn) vapours. | short term repeated exposure of 1-chloroacetophenone (cn) vapours at a concentration of 0.153 mg per litre for 15 minutes daily on 10 consecutive days in swiss albino male mice resulted in increased mortality to listeria monocytogenes. significantly elevated bacterial growth was observed in the spleen and liver of the cn exposed animals. the increased bacterial count in these organs was evident within 4-6 days post challenge as compared to vehicle exposed infected and unexposed infected animals. ... | 1992 | 1642788 |
| prevalence of listeria (spp.) in wild rats captured in the kanto area of japan. | in the kanto area a total of 245 wild rats were captured. all rats captured in ikebukuro (110 rats) and 9 out of 41 rats in yokohama were rattus rattus, and all other 126 rats were rattus norvegicus. in kashima and ikebukuro, listeria was isolated from 28 rats (77.8%) and 27 rats (24.5%), respectively, but in the other 4 areas listeria was isolated from 0-7% rats. listeria monocytogenes was isolated from 12 rats (10.9%) captured in ikebukuro and 2 rats in kashima and numazu. the frequent isolati ... | 1992 | 1643170 |
| detection of a gene encoding a phosphatidylinositol-specific phospholipase c that is co-ordinately expressed with listeriolysin in listeria monocytogenes. | a phosphatidylinositol-specific phospholipase c (pi-plc) that is unique to the pathogenic listeria species l. monocytogenes and l. ivanovii has been detected. deletion analysis performed with escherichia coli recombinants expressing pi-plc activity together with maxicell analysis showed that a 34 kda polypeptide was responsible for this activity. nucleotide sequencing revealed that the gene encoding this polypeptide comprises 317 amino acid residues with a 22-amino-acid signal peptide. this gene ... | 1991 | 1645838 |
| identification of phosphatidylinositol-specific phospholipase c activity in listeria monocytogenes: a novel type of virulence factor? | a phospholipase c which cleaves phosphatidylinositol and glycosylphosphatidylinositol (gpi) anchors was identified in listeria monocytogenes. this 36 kda protein is encoded by the gene plca, and is homologous to the bacillus cereus, bacillus thuringiensis and eukaryotic phosphatidylinositol-specific phospholipases c (pi-plc). expression of the plca gene in escherichia coli correlates with the appearance of pi-plc activity in the cells. in listeria monocytogenes, the activity is secreted to the c ... | 1991 | 1645839 |
| alveolar macrophage activation in experimental legionellosis. | legionella pneumophila is a facultative intracellular parasite of alveolar macrophages. in vitro studies have shown that lymphokine-activated mononuclear phagocytes inhibit intracellular replication of l. pneumophila. to determine if recovery from legionellosis is associated with activation of alveolar macrophages in vivo to resist l. pneumophila, we studied an animal model of legionnaires' disease. rats were exposed to aerosolized l. pneumophila and alveolar macrophages were harvested during th ... | 1991 | 1646846 |
| induction of anti-mycobacterial and anti-listerial activity of human monocytes requires different activation signals. | the requirements for activation of anti-mycobacterial and anti-listerial activity of human monocytes were investigated. human monocytes could be activated to display enhanced anti-mycobacterial activity by a 24-h treatment with lipopolysaccharide. the mediator induced by this treatment was identified as being tumour necrosis factor-alpha (tnf-alpha). addition of recombinant tnf-alpha (rtnf-alpha) to the cultures of human monocytes for 24 h yielded comparable results (minimal dose required for in ... | 1991 | 1649023 |
| in vitro activity of ly264826 compared to other glycopeptides and daptomycin. | ly264826 a new naturally occurring glycopeptide inhibited 90% of methicillin-susceptible and -resistant staphylococcus aureus at 1 micrograms/ml. ly264826 had similar activity against methicillin-susceptible and -resistant coagulase-negative staphylococci. the ly264826 mic90 for streptococcus pyogenes was 0.25 microgram/ml, twofold more active than vancomycin and twofold less active than teicoplanin. ly264826 was eightfold more active than vancomycin and twofold more active than teicoplanin agai ... | 1991 | 1651826 |
| pleiotropic control of listeria monocytogenes virulence factors by a gene that is autoregulated. | evidence for pleiotropic activation of virulence genes in listeria monocytogenes is presented. a complementation study of a spontaneous prfa-deletion mutant and analysis of cassette and transposon insertion mutants showed that the gene prfa activates the transcription of four independent genes which code for a phosphatidyl-inositol-specific phospholipase c (gene plca), listeriolysin o (gene hlya), a metallo-protease (gene prta) and a lecithinase (gene prtc). transcription of prfa is not constitu ... | 1991 | 1662763 |
| comparison of methods for discrimination between strains of listeria monocytogenes from epidemiological surveys. | total cellular dna from 28 strains of listeria monocytogenes isolated from food implicated in food-borne illness and from patients with listeriosis was digested with the restriction endonucleases hindiii, haeiii, and ecori. following agarose gel electrophoresis, the fragments were subjected to southern blot hybridization with a digoxigenin-labeled cdna probe transcribed from escherichia coli 16s and 23s rrna. the patterns of bands from genomic (dna fingerprints) and rdna fingerprints (ribotypes) ... | 1991 | 1662932 |
| phosphatidylinositol-specific phospholipase c activity as a marker to distinguish between pathogenic and nonpathogenic listeria species. | in this study, 468 listeria strains were checked for the presence of phosphatidylinositol-specific phospholipase c (pi-plc) activity by using a simple assay that consisted of overlaying colonies formed on agar plates with l-alpha-phosphatidylinositol as substrate. in this assay, pi-plc-active colonies show turbid halos around the colonies as a result of the release of insoluble diacylglycerol from the substrate. this activity was detected only in the pathogenic species listeria monocytogenes and ... | 1991 | 1662937 |
| in vitro activity of sparfloxacin (ci-978, at-4140, and pd 131501). a quinolone with high activity against gram-positive bacteria. | sparfloxacin (ci-978, at-4140 and pd 131501) is a new antimicrobial agent of the piperazinyl quinolone class. relative to other quinolones, it is a potent antistaphylococcal and antistreptococcal drug in vitro: the microbroth 90% minimum inhibitory concentration (mic90) (in microgram/ml) was 0.25 vs 26 methicillin-resistant and -sensitive coagulase-positive and -negative staphylococci and 20 streptococcus pneumoniae; 0.5 vs 20 strains each of s. pyogenes, s. agalactiae, and enterococcus faecalis ... | 1991 | 1665775 |
| guinea-pig alveolar macrophage killing of mycobacterium tuberculosis, in vitro, does not require hydrogen peroxide or hydroxyl radical. | alveolar macrophages from the lungs of guinea-pigs that had been vaccinated, boosted and then intravenously challenged with mycobacterium bovis bcg, killed both a hydrogen-peroxide-resistant and a hydrogen-peroxide-sensitive strain of m. tuberculosis, in vitro. pretreatment of the alveolar macrophages, in vitro, with catalase or mannitol, agents which remove hydrogen peroxide and the hydroxyl radical, respectively, did not decrease the extent of killing of either strain. in contrast, pretreatmen ... | 1991 | 1667538 |
| listeriosis surveillance: 1990. | the annual numbers of reports of listeriosis in england, wales and northern ireland received by the phls communicable disease surveillance centre (cdsc) and the division of microbiological reagents (dmr) have shown remarkable changes in recent years. there was a near doubling in 1987 compared to 1986; a further increase in 1988; a sharp decline in 1989 (which occurred in the second half of that year) and, finally, the total in 1990 was the lowest since 1984. the rise and fall particularly (but n ... | 1991 | 1669746 |
| [recent data on the spread of listeria spp. in the province of ferrara]. | the results of the investigations of listeria held from 1985 to 1989 in samples of foods, surface waters and stools are reported. on the whole 98 strains of listeria were isolated, 38 of which were l. monocytogenes. the first isolation of l. grayi from human stools is pointed out. | 1991 | 1670053 |
| hospital green salads and the effects of washing them. | each week from april 1989 to february 1990, a plate of green salad prepared in the hospital kitchen was examined microbiologically. of the 256 plates examined, 51% had total viable counts (tvcs) of greater than or equal to 10(5) colony forming units (cfu) g-1. staphylococcus aureus was present in 13 samples and escherichia coli in one sample. no listeria monocytogenes, clostridium perfringens or salmonella spp. were isolated. the effect of washing mustard and cress, cucumber and the different la ... | 1991 | 1674258 |
| early gamma interferon production by natural killer cells is important in defense against murine listeriosis. | a spot enzyme-linked immunosorbent assay was used to show that subcutaneous inoculation of a sublethal number of listeria monocytogenes resulted in the early appearance of gamma interferon (ifn-gamma)-producing cells in the draining lymph nodes. in contrast, inoculation of uv-killed l. monocytogenes failed to cause the appearance of ifn-gamma-producing cells. the appearance of ifn-gamma-secreting cells in response to the living organisms peaked at 24 h of infection and then declined. the drainin ... | 1991 | 1679040 |
| endogenous gamma interferon-independent host resistance against listeria monocytogenes infection in cd4+ t cell- and asialo gm1+ cell-depleted mice. | the effects of in vivo administration of antibodies against t-cell subsets and asialo gm1 (asgm1)-bearing cells on endogenous gamma interferon (ifn-gamma) production and host defense in listeria monocytogenes-infected mice were investigated. endogenous ifn-gamma titers in the bloodstreams and spleen extracts of mice on day 2 of infection were partially suppressed by administration of rabbit anti-asgm1 antibody, but not by anti-cd4 monoclonal antibody (mab) or anti-cd8 mab. of the different combi ... | 1991 | 1680104 |
| functional analysis of macrophages, b cells and splenic dendritic cells as antigen-presenting cells in west nile virus-specific murine t lymphocyte proliferation. | in this paper, the relative efficacy of macrophages, b cells and splenic dendritic cells (sdc) in presenting west nile virus (wnv) antigens to wnv memory cd4+ t cells is examined. the results indicate that, under appropriate conditions, all these cell types can function as antigen-presenting cells (apc). listeria-induced peritoneal macrophages induced higher proliferative responses than sdc or b cells derived from naive or 14 day wnv-primed mice. the ability of listeria-induced macrophage popula ... | 1991 | 1680803 |
| heat-killed listeria monocytogenes and l. monocytogenes soluble antigen induce clonable cd4+ t lymphocytes with protective and chemotactic activities in vivo. | in the present study we attempted to analyze the possibility to induce in mice a t-cell response using killed listeria monocytogenes in adjuvant. clearly, nonviable antigen is capable of inducing protective and granuloma-forming t cells in c57bl/6 mice when emulsified in complete freund's adjuvant. these t cells were cloned in vitro by using antigen and irradiated splenocytes, as antigen-presenting cells, and the clones were characterized in vivo. listeria-specific t-cell clones showed protectiv ... | 1991 | 1682264 |
| dynamics of lymphocytes and inflammatory cells recruited in liver during murine listeriosis. a cytofluorimetric study. | during primary infection of mice by listeria monocytogenes, bacterial elimination is dependent on the recruitment of myelomonocytic cells in the infectious foci and the activation of their bactericidal mechanisms through cytokines secreted by listeria-specific t lymphocytes. the immune events occurring in the liver, one of the main infected organs, have not yet been studied in detail. in the present quantitative study, we describe the dynamics of recruitment of cells belonging to the lymphoid or ... | 1991 | 1682378 |
| resolution of primary murine listeriosis and acquired resistance to lethal secondary infection can be mediated predominantly by thy-1+ cd4- cd8- cells. | mice depleted of cd4+, cd8+, thy-1+ cd4- cd8-, or all three types of cells by appropriate monoclonal antibody treatment were tested for their ability to express resistance against a primary and secondary listeria monocytogenes infection. it was found that mice depleted of cd8+, cd4+, or both of these subsets of t cells remained capable of controlling and then resolving both a primary infection and a secondary infection lethal for normal animals. in contrast, depleting mice of a population of thy ... | 1991 | 1682394 |
| lowbury lecture. listeriosis: epidemiology, virulence and the significance of contaminated foodstuffs. | recent epidemiological evidence confirms that sporadic, as well as outbreak-associated, cases of listeriosis are primarily foodborne in origin. implicated foodstuffs include meat products, dairy products, fruit, seafood and raw and processed vegetables. large community-acquired outbreaks in north america and europe have been complemented by smaller outbreaks involving hospitalized patients. anecdotal reports and case clusters of nosocomial cases also support foodborne transmission. cross-infecti ... | 1991 | 1686033 |
| bacteriological safety of cook-chill food at the royal free hospital, with particular reference to listeria. | cook-chill food prepared by the catering department of the royal free hospital was examined over an 8-month period commencing october 1989. total aerobic viable counts (tavcs) were performed on 200 food specimens which were also examined for listeria using selective enrichment culture. ten of 200 food samples tested had tavcs greater than 10(5) colony forming units (cfu) g-1, and nine of these were from non-vegetarian (meat) dishes. although most of the food prepared by cook-chill had microbial ... | 1991 | 1686034 |
| isolation of listeria species from precooked chilled foods. | cook-chill food prepared commercially was introduced to serve our patients and staff in 1989. the presence of listeria monocytogenes in samples taken before regeneration was examined over two periods. for period a (april-november 1989), c. 0.2 g of food was examined; 2.7% of 992 meat samples and 0.6% of 1084 samples of other types of food were found to contain the organism. as a result, cold sliced meat was withdrawn from the patients' menu. for period b (february-july 1990), following the intro ... | 1991 | 1686035 |
| induction of macrophage-mediated tumor cytotoxicity by a hamster monoclonal antibody with specificity for lipopolysaccharide receptor. | experiments have been carried out to assess the immunostimulatory activity of a hamster igm mab (mab5d3) with specificity for an 80-kda lps-binding protein expressed on murine macrophages and monocytes. the addition of mab5d3 to cultures of murine bone marrow-derived macrophages activated these cells to become tumoricidal for mastocytoma cells in vitro. the activity of mab5d3 was enhanced in the presence of ifn-gamma. neither mab5d3 nor lps were able to activate macrophages from the lps-hyporesp ... | 1990 | 1694209 |
| [new knowledge of pathogenesis and immunity in listeria infection]. | | 1990 | 1694371 |
| bacteria-infected fibroblasts have enhanced susceptibility to the cytotoxic action of tumor necrosis factor. | the susceptibility of bacteria-infected fibroblasts to the cytotoxic action of tumor necrosis factor was investigated. l cells infected with shigella flexneri, salmonella typhimurium, or listeria monocytogenes, had an enhanced susceptibility to the cytotoxic activity of tnf-alpha. this enhanced susceptibility was dependent upon the challenge dose of bacteria, the concentration of tnf, and upon the exposure time of bacteria-infected cells to tnf. l cells infected with s. flexneri were susceptible ... | 1990 | 1694886 |
| examination of immune parameters and host resistance mechanisms in b6c3f1 mice following adult exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin. | adult female b6c3f1 mice were given a single ip dose of 0, 01, 1.0, or 10.0 micrograms/kg 2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd) and examined for immune function and host resistance 7-10 d later. exposure to tcdd resulted in a significant dose-related decrease in induction of both igm and igg antibody-forming cells. this suppression was noted for both t-dependent and t-independent antigens. tcdd at a dosage of 10 micrograms/kg was shown to suppress production of antibody to viral hemagglutin ... | 1990 | 1700136 |
| canine hepatic vein branches associated with subendothelial mast cells and an adventitial lymphatic plexus. | branches of the hepatic veins in the dog are equipped with peculiar, periodically arranged sphincter muscles which are known to constrict in response to hematogenous shock agents, causing the severe hepatic congestion characteristic of this species. as was confirmed in this study, the sphincters are more strongly and effectively disposed in the peripheral portion of the veins, including the sublobular and central veins. mast cells were numerous around the sublobular branches, being specifically ... | 1990 | 1701311 |
| revision of the o antigenic scheme of listeria. | factor sera against listeria o antigens (serologic reference strains) were produced. the results confirm the validity of the o antigenic scheme established for listeria, but show slight discrepancies in strains of serovars 4b, 4ab and 6b. | 1990 | 1702255 |
| identification of a new operon involved in listeria monocytogenes virulence: its first gene encodes a protein homologous to bacterial metalloproteases. | the region flanking the transposon in a tn1545-induced lecithinase-negative mutant of listeria monocytogenes egd was cloned and sequenced. the transposon had inserted in orf d, the open reading frame previously identified downstream from hlya, the gene encoding listeriolysin o. the complete sequence of orf d from strain egd has been determined as well as that of two other strains: lo28, a clinical isolate; and lm8, an epidemic strain. orf d is 1,533 bp long and encodes a protein highly homologou ... | 1991 | 1705239 |
| role of listeriolysin-o (llo) in the t lymphocyte response to infection with listeria monocytogenes. identification of t cell epitopes of llo. | using a murine model, we investigated the role of the bacterial exotoxin listeriolysin o (llo) in cellular immunity to listeria monocytogenes. a correlation between llo production by infecting bacteria and generation of protective immunity to virulent llo-producing bacteria was noted. using isogeneic hemolysin (hly+ or hly-) strains of l. monocytogenes, we demonstrated that llo production by infecting bacteria is required to elicit t cells reactive both to bacteria-associated ag and to the secre ... | 1991 | 1709197 |
| gamma/delta t cells and bacteria. | | 1990 | 1710367 |
| [prevalence of listeria monocytogenes infection in a rome population group]. | | 1990 | 1711344 |
| neonatal listeria monocytogenes infection is refractory to interferon. | despite aggressive treatment, early onset neonatal listeria monocytogenes infection continues to have high morbidity and mortality. we recently showed that pretreatment of newborn l. monocytogenes-infected rats with interferon (ifn)-alpha/beta or recombinant rat ifn-gamma dramatically improves survival. however, in the present experiment, when newborn rats were treated with ifn-alpha/beta or recombinant rat ifn-gamma after intraperitoneal injection with listeria there was no benefit. because mos ... | 1991 | 1712935 |
| phylogenetic analysis of the genus listeria based on reverse transcriptase sequencing of 16s rrna. | the phylogenetic interrelationships of members of the genus listeria were investigated by using reverse transcriptase sequencing of 16s rrna. the sequence data indicate that at the intrageneric level the genus listeria consists of the following two closely related but distinct lines of descent: (i) the listeria monocytogenes group of species (including listeria innocua, listeria ivanovii, listeria seeligeri, and listeria welshimeri) and (ii) the species listeria grayi and listeria murrayi. at th ... | 1991 | 1713054 |
| development and characterization of a monoclonal antibody specific for listeria monocytogenes and listeria innocua. | balb/c mice were immunized with crude cell surface proteins of listeria monocytogenes v7. approximately 1,680 hybridomas were generated after two fusions, and the monoclone c11e9 was selected and used for further characterization. the monoclonal antibody (mab) produced by c11e9 was immunoglobulin subclass g2b with kappa light chains. dot and colony blot results indicated that mab c11e9 was reactive to all the l. monocytogenes (34 of 34) and listeria innocua (6 of 6) isolates without any cross-re ... | 1991 | 1715321 |
| dna polymorphism in strains of listeria monocytogenes. | dna polymorphism in 35 listeria monocytogenes strains belonging to serovars 1/2a, 1/2b, 1/2c, and 4b was studied by genomic dna digestion. the restriction endonucleases apai and noti, which cleave dna at rare sequences, were used, and dna fragments were analyzed by pulsed-field gel electrophoresis. restriction fragment length polymorphism varied among different serovars and was used for epidemiological studies, but serovar 1/2c isolates could not be analyzed because their restriction patterns we ... | 1991 | 1715882 |
| enhanced resistance against listeria monocytogenes achieved by pretreatment with granulocyte colony-stimulating factor. | phagocytosis, h2o2 production, mac-1 expression, and in vivo elimination of listeria monocytogenes were enhanced in granulocyte colony-stimulating factor (g-csf)-treated mice. transfer of polymorphonuclear leukocytes prolonged survival of mice infected with a lethal dose of l. monocytogenes. g-csf augments the functions of polymorphonuclear leukocytes and thus plays a role in protection. | 1991 | 1718880 |
| precise prediction of a dominant class i mhc-restricted epitope of listeria monocytogenes. | listeria monocytogenes is a gram-positive bacterium which grows in the cytoplasm of eukaryotic cells and can cause severe disease in immunocompromised individuals. in murine systems cd8+ t lymphocytes have been shown to be important effectors of acquired protective immunity against l. monocytogenes. class i mhc-restricted cd8+ cytotoxic t lymphocytes (ctl), which lyse j774 macrophage-like targets infected with l. monocytogenes, are induced following in vivo injection of live organisms. natural p ... | 1991 | 1719425 |
| specific interaction between listeria monocytogenes and glycosylated albumins. | we have previously shown that listeria monocytogenes serovar 1/2b can bind strongly to bovine albumin (ba) glycosylated by glucosamine or fucosylamine with about 20 to 30 carbohydrate residues per albumin molecule. we now show that the binding is time-dependent, reversible, saturable and specific. the two glycosylated compounds inhibit each other competitively. scatchard analysis showed that about 100 molecules of ba-glucosamide (heptameric configuration) and 14,300 molecules of ba-fucosylamide ... | 1991 | 1719588 |
| [review of the distribution of listeria monocytogenes and listeriosis]. | | 1990 | 1719994 |
| development of a 16s rrna-based oligomer probe specific for listeria monocytogenes. | crude rrna was isolated from listeria monocytogenes, l. innocua, and l. ivanovii and sequenced by a reverse transcriptase method. only two sequence regions were found to differ for l. monocytogenes versus l. innocua or l. ivanovii. two oligonucleotide probes (rl-1 and rl-2) complementary to these two regions of rrna of l. monocytogenes were synthesized. the rl-1 probe had one base while the rl-2 probe had two bases which differed for l. monocytogenes versus l. innocua and l. ivanovii. use of a d ... | 1991 | 1723868 |
| bacterial determinants of intracellular growth of listeria monocytogenes. | | 1991 | 1726613 |
| coordinate regulation of virulence genes in listeria monocytogenes requires the product of the prfa gene. | the prfa gene of listeria monocytogenes encodes a protein that activates transcription of the listeriolysin gene (lisa). in order to explore the role of the prfa gene product in the pathogenesis of listerial infection, we constructed a site-directed insertion mutation in prfa by the chromosomal integration of a novel suicide vector containing a portion of the prfa coding region. this mutation not only transcriptionally silenced the listeriolysin (lisa) gene but also abrogated production of speci ... | 1992 | 1729245 |
| macrophage functions are regulated by murine decidual and tumor extracellular matrices. | because of their paternal antigens, the fetus and placenta may be considered an allograft in the maternal host. understanding the mechanisms which prevent maternal immunological rejection of the fetus remains a fundamental unsolved problem in immunology. we have previously reported that macrophages are inhibited by maternal decidual stromal cells residing at the maternal-fetal interface. in view of the central role of macrophages in cell-mediated immunity, this inhibition may contribute to preve ... | 1992 | 1729266 |
| metabolic requirements for macrophage presentation of listeria monocytogenes to immune cd8 cells. | though ingested ag are readily degraded into peptides within endocytic vesicles, apc usually cannot present these fragments to cd8 cells. despite this generalization, some exceptions have been noted. for example, murine macrophage targets readily process heat-killed listeria monocytogenes (hklm) into a form recognizable by immune cd8 ctl. using an assay of listeria-specific, cd8-mediated cytotoxicity to quantitate ag presentation by c57bl/6 macrophage targets, we have examined some of the cellul ... | 1992 | 1729372 |
| role of gamma interferon and tumor necrosis factor alpha in resistance to salmonella typhimurium infection. | in mice infected with a sublethal dose of salmonella typhimurium, the injection of an anti-gamma interferon (ifn-gamma) monoclonal antibody increased bacterial proliferation in the spleen and led to death on day 7 or 8. depletion of both cd4+ and cd8+ t cells with monoclonal antibodies in vivo had a much less marked effect during the first week of infection than the administration of anti-ifn-gamma antibodies, suggesting that cells other than t lymphocytes participate in the production of ifn-ga ... | 1992 | 1730475 |
| endogenous tumor necrosis factor, interleukin-6, and gamma interferon levels during listeria monocytogenes infection in mice. | mice were infected intravenously with a sublethal dose of listeria monocytogenes cells and then levels of tumor necrosis factor (tnf), interleukin-6 (il-6), and gamma interferon (ifn-gamma) in the bloodstreams, spleens, and livers were monitored. the maximum level of tnf was detected at 72 h in the spleens and livers, but tnf was never detected in the bloodstreams. il-6 appeared in the bloodstreams and spleens and peaked at 48 h. the maximum level of ifn-gamma could be detected in all three spec ... | 1992 | 1730485 |
| the expression of virulence genes in listeria monocytogenes is thermoregulated. | the expression of listeriolysin, a major virulence factor of the gram-positive facultative intracellular pathogen listeria monocytogenes, is positively regulated by a transcriptional activator, the prfa gene product. we had previously shown that mutations within the prfa gene lead to loss of listeriolysin production. in this communication, the regulation of expression of listeriolysin by a specific environmental condition, namely, temperature, was studied in wild-type strains of listeria monocyt ... | 1992 | 1732227 |
| the prevalence of potential pathogenic micro-organisms in the endocervix of pregnant women at tygerberg hospital. | the prevalence of potential pathogenic organisms cultured from the endocervix in 206 pregnant patients was: ureaplasma urealyticum 63%, mycoplasma hominis 39%, candida albicans 20%, chlamydia trachomatis 11%, neisseria gonorrhoeae 7%, group b beta-haemolytic streptococcus 6% and listeria monocytogenes 1%. the most common complications of pregnancy found were: preterm labour 14%, urinary tract infection 8% and premature rupture of membranes 4%. significantly more patients in whom c. trachomatis o ... | 1992 | 1734556 |
| transcriptional activation of the listeria monocytogenes hemolysin gene in bacillus subtilis. | the prfa gene of listeria monocytogenes was recently reported to be required for expression of hly, which encodes a pore-forming hemolysin essential for pathogenicity (m. leimeister-wachter, c. haffner, e. domann, w. goebel, and t. chakraborty, proc. natl. acad. sci. usa 87:8336-8340, 1990). we demonstrate here that a hly-lacz fusion introduced into bacillus subtilis is strongly activated when the prfa gene product is supplied in trans under the control of an isopropyl-beta-d-thiogalactopyranosi ... | 1992 | 1735720 |
| survey of neonatal meningitis in australia: 1987-1989. | to identify incidence, bacterial aetiology, outcome after treatment and risk factors for poor outcome of neonatal meningitis. | 1992 | 1738323 |
| listeria monocytogenes causing endovascular infection. | listeria monocytogenes is an uncommon cause of mycotic aneurysms, endocarditis, and other endovascular infections. when they occur, these infections usually involve patients with relatively normal host defenses, but with abnormal vascular intima or cardiac valves. we have reported a listeria monocytogenes infection at the site of a posttraumatic aortic aneurysm. | 1992 | 1738888 |
| listeria monocytogenes meningitis at king edward viii hospital, durban. a 10-year experience, 1981-1990. | nine cases, 3 adults and 6 children, with listeria monocytogenes meningitis were seen over a 10-year period at king edward viii hospital, durban. these cases accounted for 0.8% (3/374) and 0.6% (6/1,210) of all culture-positive cases of acute bacterial meningitis in adults and children, respectively, and represented 2.9% (4/136) of all culture-positive cases in the neonatal age group and 5.7% (3/53) of culture-positive cases in adults 50 years and older. the patients had positive blood and cereb ... | 1992 | 1738904 |
| l. monocytogenes-induced actin assembly requires the acta gene product, a surface protein. | the intracellular pathogenic bacterium l. monocytogenes can spread directly from cell to cell without leaving the cytoplasm. the mechanism of this movement, generated through bacterially induced actin polymerization, is not understood. by analyzing an avirulent tn917-lac mutant defective for actin polymerization, we have identified a bacterial component involved in this process. the transposon had inserted in acta, the second gene of an operon. gene disruption of downstream genes and transformat ... | 1992 | 1739966 |
| induction of macrophage interleukin-1 production by listeria monocytogenes hemolysin. | listeriolysin o produced by a hemolytic strain of listeria monocytogenes was purified from the ammonium sulfate precipitate of a culture supernatant through the steps of ion-exchange chromatography and gel filtration. the purified hemolysin finally gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with a molecular weight of 58,000. when peritoneal exudate macrophages were stimulated with purified hemolysin, we found a high level of il-1 activity as determined by thy ... | 1992 | 1739985 |
| protective immunity and granulomatous inflammation is mediated in vivo by t cells reactive to epitopes common to avirulent and listeriolysin-negative mutants of listeria monocytogenes. | the ability of several listeriolysin o-negative mutants of the egd and nctc 7973 strains of listeria monocytogenes to activate specific t cell responses in vitro and in vivo was determined. t cell lines from different inbred mouse strains and derived t cell clones elicited by l. monocytogenes, strain egd, which are able to adoptively transfer protection and granuloma formation were examined. specificity testing revealed no differences between listeriolysin-positive and -negative strains to induc ... | 1992 | 1739988 |
| intraepithelial airway dendritic cells: a distinct subset of pulmonary dendritic cells obtained by microdissection. | dendritic cells (dc), in general, and pulmonary dc, in particular, are a heterogeneous population of cells, their phenotype and function being dependent on their anatomic location, their state of activation, and the regulatory effect of locally secreted cytokines. using a novel microdissection technique, the epithelium from the trachea and entire airway system was harvested, and the contained dc isolated at greater than 90% purity. the phenotype and function of these airway dc (adc) was compared ... | 1992 | 1740664 |
| the protective activity of immunostimulants against listeria monocytogenes infection in mice. | the function of peritoneal macrophages induced by intraperitoneal (i.p.) injection of attenuated streptococcus pyogenes (ok-432), bacillus calmette guérin (bcg), protein-bound polysaccharide preparation isolated from coriolus vesicolor (psk) or lactobacillus casei was examined. the pma-triggered respiratory burst (production of o2- and h2o2) of macrophages induced by ok-432, bcg or lac. casei was greater than that of resident or thioglycollate-stimulated macrophages and was similar to that of bc ... | 1992 | 1740781 |
| the effect of microwave and conventional cooking on the temperature profiles and microbial flora of minced beef. | beef mince samples were cooked to the rare, medium and well done states by microwave and conventional oven methods. the raw samples all contained large numbers of contaminating organisms and low numbers of listeria monocytogenes were detected in the majority of samples. a substantial proportion of the contaminating flora survived in mince cooked by microwaves to the rare, medium and well done states, prior to a 30-min standing period. listeria monocytogenes survived in all samples cooked by micr ... | 1991 | 1742174 |
| the effects of temperature, ph, sodium chloride and sodium nitrite on the growth of listeria monocytogenes. | an automated turbidimetric system using multiwelled plates was used to examine the effects of different combinations of nacl (0.5-8.0% w/v), nano2 (0-400 micrograms/ml) ph (4.6-7.4) and temperature (5-30 degrees c) on the growth of listeria monocytogenes in tryptone soya broth. the data presented clearly illustrate the combinations that permit visible growth of the organism. the ability of l. monocytogenes to grow at low ph levels was strongly influenced by incubation temperature as well as nano ... | 1991 | 1742175 |
| development of an improved chemically defined minimal medium for listeria monocytogenes. | a chemically defined minimal medium for listeria monocytogenes has been developed by modification of welshimer's medium. the growth factors required by l. monocytogenes scott a are leucine, isoleucine, arginine, methionine, valine, cysteine (each at 100 mg/liter), riboflavin and biotin (each at 0.5 micrograms/ml), thiamine (1.0 micrograms/ml), and thioctic acid (0.005 micrograms/ml). growth was stimulated by 20 micrograms of fe3+ per ml as ferric citrate. glucose (1%) and glutamine (600 mg/liter ... | 1991 | 1746963 |