Vet Microbiol, 1997 Sep, 57(2-3), 171 - 80 Radioactive technetium-99m labelling of Salmonella abortusovis for the assessment of bacterial dissemination in sheep by in vivo imaging; Perin F et al.; We report the development and validation of a 99mTc-labelling technique of bacteria, applied to Salmonella abortusovis . The radioactive labelling is obtained using a pre-tinning step of the cells followed by direct incubation of S . abortusovis suspension with 99mTc-pertechnetate . Several procedures with different amounts of stannous tin (SnF2 or SnCl2) were evaluated . The selected method, respectful of bacterial viability, provided a 30% labelling yield . Viability of 99mTc-labelled bacteria was assessed by flow cytometry using rhodamine 123 and was demonstrated to be unchanged, turbidimetric measurements showing only a slight increase in the growth rate for radiolabelled cells . Incubation of 99mTc-labelled S . abortusovis with pronase, saponine and urea demonstrated labelling stability and suggested an intra-cellular localization for 99mTc . A preliminary study was also conducted in sheep to evaluate the value of the imaging of radiolabelled S . abortusovis . Spatial and temporal patterns of their in vivo dissemination in the lymphatic system after a sub-cutaneous injection were compared with control lymphoscintigraphic agents . These imaging data supported the assumption that the radioactivity detected in vivo was proportional to the number of 99mTc-labelled bacteria. Philos Trans R Soc Lond B Biol Sci, 1997 Sep 29, 352(1359), 1331 - 45 Immunogenetics of leishmanial and mycobacterial infections: the Belem Family Study; Blackwell JM et al.; In the 1970s and 1980s, analysis of recombinant inbred, congenic and recombinant haplotype mouse strains permitted us to effectively 'scan' the murine genome for genes controlling resistance and susceptibility to leishmanial infections . Five major regions of the genome were implicated in the control of infections caused by different Leishmania species which, because they show conserved synteny with regions of the human genome, immediately provides candidate gene regions for human disease susceptibility genes . A common intramacrophage niche for leishmanial and mycobacterial pathogens, and a similar spectrum of immune response and disease phenotypes, also led to the prediction that the same genes/candidate gene regions might be responsible for genetic susceptibility to mycobacterial infections such as leprosy and tuberculosis . Indeed, one of the murine genes (Nramp1) was identified for its role in controlling a range of intramacrophage pathogens including leishmania, salmonella and mycobacterium infections . In recent studies, multicase family data on visceral leishmaniasis and the mycobacterial diseases, tuberculosis and leprosy, have been collected from north-eastern Brazil and analysed to determine the role of these candidate genes/regions in determining disease susceptibility . Complex segregation analysis provides evidence for one or two major genes controlling susceptibility to tuberculosis in this population . Family-based linkage analyses (combined segregation and linkage analysis; sib-pair analysis), which have the power to detect linkage between marker loci in candidate gene regions and the putative disease susceptibility genes over 10-20 centimorgans, and transmission disequilibrium testing, which detects allelic associations over 1 centimorgan (ca . 1 megabase), have been used to examine the role of four regions in determining disease susceptibility and/or immune response phenotype . Our results demonstrate: (i) the major histocompatibility complex (MHC: H-2 in mouse, HLA in man: mouse chromosome 17/human 6p; candidates class II and class III including TNF alpha/beta genes) shows both linkage to, and allelic association with, leprosy per se, but is only weakly associated with visceral leishmaniasis and shows neither linkage to nor allelic association with tuberculosis; (ii) no evidence for linkage between NRAMP1, the positionally cloned candidate for the murine macrophage resistance gene Ity/Lsh/Bcg (mouse chromosome 1/human 2q35), and susceptibility to tuberculosis or visceral leishmaniasis could be demonstrated in this Brazilian population; (iii) the region of human chromosome 17q (candidates NOS2A, SCYA2-5) homologous with distal mouse chromosome 11, originally identified as carrying the Scl1 gene controlling healing versus nonhealing responses to Leishmania major, is linked to tuberculosis susceptibility; and (iv) the 'T helper 2' cytokine gene cluster (proximal murine chromosome 11/human 5q; candidates IL4, IL5, IL9, IRF1, CD14) controlling later phases of murine L . major infection, is not linked to human disease susceptibility for any of the three infections, but shows linkage to and highly significant allelic association with ability to mount an immune response to mycobacterial antigens . These studies demonstrate that the 'mouse-to-man' strategy, refined by our knowledge of the human immune response to infection, can lead to the identification of important candidate gene regions in man. Microbiology, 1997 Oct, 143 ( Pt 10), 3201 - 7 Peptides 14VIDLL18 and 96FEAAAL101 defined as epitopes of antibodies raised against amino acid sequences of enterotoxigenic Escherichia coli colonization factor antigen I fused to Salmonella flagellin; Luna MG et al.; Antibodies raised against four hybrid Salmonella flagellins carrying amino acid sequences derived from the fimbrial subunit of the colonization factor I antigen (CFA/I) of enterotoxigenic Escherichia coli (ETEC), i.e . hybrid flagellins Fla I (aa 1-15), Fla II (aa 11-25), Fla III (aa 32-45) and Fla IV (aa 88-102), were not able to inhibit the in vitro binding of CFA/I-expressing ETEC bacteria to enterocyte-like Caco-2 cells . However, one of the hybrid flagellins (Fla II) was recognized by a previously described anti-CFA/I subunit mAb (S-CFA/I 17:8) which was able to block adhesion of CFA/I-expressing bacteria to Caco-2 cells and to bind to the amino acid sequences 15IDLLQ19 of the CFA/I fimbrial subunit . Pepscan analysis of antibodies raised against the hybrid flagellins Fla II and Fla IV showed that they were specific for the sequences 14VIDLL18 and 96FEAAAL101, respectively, of the CFA/I fimbrial subunit . Thus, the discrepancy in the abilities of the anti-Fla II serum and the mAb S-CFA/I 17:8 to block binding might be ascribed to their slightly different fine specificity for epitopes. Zentralbl Hyg Umweltmed, 1996 Nov, 199(1), 84 - 90 An evaluation of certain Salmonella detection methods in surface water; Bernagozzi M et al.; Two different procedures were employed for detecting Salmonella spp . in environmental water samples: a rapid method (enrichment in Salmosyst Broth and plating in Rambach Agar-Merck) and a longer assay (pre-enrichment in Buffered Peptone Water, enrichment in Selenite-Cistyne Broth and plating in Brilliant Green Agar-Difco) . The efficiency of microbiological tests was measured by the following criteria: recovery, sensitivity and specificity . The results analysed by the Kendall concordance coefficients demonstrated that the rapid method appeared more effective even if poorly specific. Infect Immun, 1997 Nov, 65(11), 4624 - 33 Salmonellae activate tumor necrosis factor alpha production in a human promonocytic cell line via a released polypeptide; Ciacci-Woolwine F et al.; Invasive strains of Salmonella spp . cause both systemic and localized infections in humans . The ability to resist infection and some aspects of the tissue pathology associated with the presence of Salmonella in the gastrointestinal tract have been shown to be mediated in part by the induction of tumor necrosis factor alpha (TNF-alpha), a proinflammatory cytokine produced by activated macrophages and lymphocytes . Recent reports indicate that TNF-alpha is involved in the induction of human immunodeficiency virus replication by Salmonella in the latently infected human promonocytic cell line U1 . In the present study, we investigated the effects of Salmonella on TNF-alpha production in U1 cells and a related cell line, U38 . Unlike Escherichia coli or Yersinia enterocolitica, salmonellae rapidly induce TNF-alpha expression in these cells through a released factor(s) . Time course experiments show that the kinetics of TNF-alpha production by U38 cells stimulated with Salmonella conditioned medium closely resemble those observed in response to live Salmonella . The observation that TNF-alpha levels are elevated by 60 min after exposure to either bacteria or their conditioned medium suggests that the soluble inducer is continuously released or shed by the bacteria and that the signal acts rapidly to increase TNF-alpha production . Furthermore, the ability to produce the TNF-alpha inducer is shared by at least four Salmonella serotypes and does not correlate with the abilities to invade and to survive within phagocytes . Treatment of active conditioned medium with trypsin, but not low pH, high temperature, or urea, significantly inhibits its TNF-alpha-inducing effect on U38 cells, a finding which points to a polypeptide product of Salmonella as the mediator of TNF-alpha production . Gel filtration chromatography of Salmonella conditioned medium reveals two peaks of activity, consistent with molecular masses of approximately 150 and 110 kDa. J Bacteriol, 1997 Nov, 179(21), 6551 - 9 Evolutionary genetics of the isocitrate dehydrogenase gene (icd) in Escherichia coli and Salmonella enterica; Wang FS et al.; Sequences of the icd gene, encoding isocitrate dehydrogenase (IDH), were obtained for 33 strains representing the major phylogenetic lineages of Escherichia coli and Salmonella enterica . Evolutionary relationships of the strains based on variation in icd are generally similar to those previously obtained for several other housekeeping and for invasion genes, but the sequences of S . enterica subspecies V strains are unusual in being almost intermediate between those of the other S . enterica subspecies and E . coli . For S . enterica, the ratio of synonymous (silent) to nonsynonymous (replacement) nucleotide substitutions between pairs of strains was larger than comparable values for 12 other housekeeping and invasion genes, reflecting unusually strong purifying selection against amino acid replacement in the IDH enzyme . All amino acids involved in the catalytic activity and conformational changes of IDH are strictly conserved within and between species . In E . coli, the level of variation at the 3' end of the gene is elevated by the presence in some strains of a 165-bp replacement sequence supplied by the integration of either lambdoid phage 21 or defective prophage element e14 . The 72 members of the E . coli Reference Collection (ECOR) and five additional E . coli strains were surveyed for the presence of phage 21 (as prophage) by PCR amplification of a phage 21-specific fragment in and adjacent to the host icd, and the sequence of the phage 21 segment extending from the 3' end of icd through the integrase gene (int) was determined in nine strains of E . coli . Phage 21 was found in 39% of E . coli strains, and its distribution among the ECOR strains is nonrandom . In two ECOR strains, the phage 21 int gene is interrupted by a 1,313-bp insertion element that has 99.3% nucleotide sequence identity with IS3411 of E . coli . The phylogenetic relationships of phage 21 strains derived from sequences of two different genomic regions were strongly incongruent, providing evidence of frequent recombination. Lett Appl Microbiol, 1997 Oct, 25(4), 246 - 8 Use of antibody-coated cellulose sponges for enhanced isolation of salmonella; Davies RH et al.; One thousand, four hundred and fifty-one naturally contaminated samples from pig, poultry and cattle farms, poultry hatcheries and animal feed mills were examined in a trial in which transfer of small portions of cellulose sponge coated with salmonella somatic polyvalent antiserum was compared with transfer of standard liquid inocula from pre-enrichment to selective enrichment culture . Salmonella was found in 281 (19.4%) of the samples using the standard method, compared with 385 (26.5%) using the sponge method . It was therefore concluded that antibody-coated cellulose sponges could be a simple means of increasing the recovery of salmonellas from pre-enrichment broths and thereby enhancing the test sensitivity. J Appl Microbiol, 1997 Oct, 83(4), 445 - 55 The use of an automated growth analyser to measure recovery times of single heat-injured Salmonella cells; Stephens PJ et al.; A new approach to the study of recovery times of single heat-injured Salmonella cells is described . It comprises the generation of a standard heat-injured culture, serial dilution of this culture to near extinction, inoculation of the serial dilutions across many microtitre plates and measurement of the subsequent recovery and growth using an automated turbidometric analyser . Lag times for individual cells were estimated from turbidity data using a model that accurately extrapolated the growth curve back to the starting inoculum level . Lag times were compared using a number of different commercially available pre-enrichment media . The most typical result was a very broad distribution of lag times at the single cell inoculum level, with many values in excess of 20 h . Even at an inoculum level 10-fold higher, lag times for some injured cells were estimated to be > 10 h . More significantly, it was found that some media recovered more injured cells than others and vice versa . Between the worst and best media there were as many as 3 log10 cycles difference in the number of cells recoverable . No trends were apparent linking choice of medium with performance . The implications of these findings, in relation to traditional and rapid methodology, are discussed. J Appl Microbiol, 1997 Oct, 83(4), 438 - 44 Immersion heat treatments for inactivation of Salmonella enteritidis with intact eggs; Schuman JD et al.; The effects of water-bath immersion heat treatments on the inactivation of Salmonella enteritidis within intact shell eggs were evaluated . Six pooled strains of Salm . enteritidis (ca 3 x 10(8) cfu, inoculated near the centre of the yolk) were completely inactivated within 50-57.5 min at a bath temperature of 58 degrees C and within 65-75 min at 57 degrees C (an 8.4 to 8.5-D process per egg) . Following the initial 24 to 35-min come-up period, semilogarithmic survivor curves obtained at 58 and 57 degrees C yielded apparent decimal reduction times (D-values) of 4.5 and 6.0 min, respectively . Haugh unit values increased during heating, while yolk index and albumen pH values were unaffected . Albumen clarity and functionality were affected by the thermal treatments; therefore, extended whip times would be required for meringue preparation using immersion-heated egg whites . Immersion-heated shell eggs could provide Salmonella-free ingredients for the preparation of a variety of minimally-cooked foods of interest to consumers and foodservice operators. J Appl Microbiol, 1997 Oct, 83(4), 407 - 12 Determination of the influence of organic acids and nisin on shelf-life and microbiological safety aspects of fresh pork sausage; Scannell AG et al.; The effect of replacing sulphur dioxide with organic acids and nisin to reduce the microbial counts in fresh pork sausage was examined . The potential of sodium citrate or sodium lactate, used singly or in combination with nisin, was also assessed in sausage inoculated with Staphylococcus aureus MMPR 3 and Salmonella kentucky AT 1 . The results indicate that a combination of sodium lactate and nisin wa particularly effective in reducing total bacterial counts in this food product . It also appears that this combination provides an increased protection against common pathogenic contaminants of fresh pork sausage, i.e . Staph . aureus and Salmonella species. Acta Paediatr, 1997 Oct, 86(10), 1056 - 8 Salmonella meningitis: clinical experience of third-generation cephalosporins; Huang LT et al.; Fifteen paediatric patients with Salmonella meningitis were retrospectively reviewed . Presenting symptoms and signs included fever, vomiting, seizures, poor activity, diarrhoea and bulging anterior fontanelle in most patients . Seven out of eight patients with prolonged fever for > 10 days had neurologic sequelae; therefore, prolonged fever is a significant prognostic factor of a poor outcome (p < 0.005) . All 15 patients had a brain ultrasound or computed tomography in the acute stage and 11 patients had abnormal findings . The 14 surviving patients were treated with a third-generation cephalosporin for at least 3 weeks . Seven patients (47%) made complete recoveries; two of them were treated solely with a third-generation cephalosporin . Only one mortality (6%) occurred and there were no relapses . In conclusion, high frequencies of prolonged fever, neuroimaging abnormalities and neurologic sequelae were seen in patients with Salmonella meningitis treated with third-generation cephalosporins. J Clin Microbiol, 1997 Nov, 35(11), 2786 - 90 Human salmonellosis associated with exotic pets; Woodward DL et al.; During the period from 1994 to 1996, an increase in the number of laboratory-confirmed cases of human salmonellosis associated with exposure to exotic pets including iguanas, pet turtles, sugar gliders, and hedgehogs was observed in Canada . Pet turtle-associated salmonellosis was recognized as a serious public health problem in the 1960s and 1970s, and in February 1975 legislation banning the importation of turtles into Canada was enacted by Agriculture Canada . Reptile-associated salmonellosis is once again being recognized as a resurgent disease . From 1993 to 1995, there were more than 20,000 laboratory-confirmed human cases of salmonellosis in Canada . The major source of Salmonella infection is food; however, an estimated 3 to 5% of all cases of salmonellosis in humans are associated with exposure to exotic pets . Among the isolates from these patients with salmonellosis, a variety of Salmonella serotypes were also associated with exotic pets and included the following: S . java, S . stanley, S . poona, S . jangwani, S . tilene, S . litchfield, S . manhattan, S . pomona, S . miami, S . rubislaw, S . marina subsp . IV, and S . wassenaar subsp . IV. Am J Trop Med Hyg, 1997 Oct, 57(4), 438 - 44 Enteropathogenic bacteria in the La Paz River of Bolivia; Ohno A et al.; Diarrheal diseases often result from ingestion of contaminated water or food . The population of La Paz, Bolivia is directly or indirectly exposed to the sewage-contaminated La Paz River . We conducted a bacteriologic survey of the La Paz River to quantify the level of bacterial contamination, with particular reference to enteropathogens . A total bacterial count exceeding 10(6) colony-forming units (CFU)/ml, including lactose fermenting and nonfermenting, gram-negative bacilli of approximately 10(5) CFU/ml, respectively, were detected in river water samples collected near two densely populated areas . A total bacterial count of 10(5) CFU/ml was also detected at the most downstream area of the river near a sparsely populated area . At four sampling locations, several enteropathogens were detected, including five enterotoxigenic Escherichia coli (ETEC) (serotype O6, O15, and O159), two enteropathogenic E . coli (EPEC) (serotype O44), two enteroinvasive E . coli (EIEC) (serotype O29), and three Salmonella O4 group isolates . The heat-labile enterotoxin gene and the invasive toxin gene were detected in all ETEC and EIEC isolates by polymerase chain reaction analysis . Nine isolates of E . coli were found by the agar dilution method to be susceptible to ampicillin, kanamycin, nalidixic acid, tetracycline, and chloramphenicol, and ampicillin resistance was found in only two isolates of EIEC 7-4 (serotype O29) and EPEC 7-5 (serotype O44) . Ampicillin resistance was coded on plasmids and transferred conjugatively to E . coli chi1037 at a frequency of 10(-5) CFU/donor by the broth mating method . Strains of Aeromonas caviae, which can cause diarrheal disease in infants, were detected in vegetables grown in fields irrigated by water from the La Paz River . The survival of nine isolates of E . coli in filtered river water was compared with that of laboratory strains (E . coli chi1037, W3110, and ATCC29577) . The survival time of seven isolates, excluding two ampicillin-resistant isolates, was markedly longer than that of the laboratory strains . Our results show a high bacterial contamination of the La Paz river and suggest that such levels may contribute to the high incidence of diarrheal disease in the city of La Paz. J Med Assoc Thai, 1997 Sep, 80 Suppl 1, S149 - 54 Immunopharmacological activity of polysaccharide from the pericarb of mangosteen garcinia: phagocytic intracellular killing activities; Chanarat P et al.; Polysaccharides from the pericarbs of mangosteen, Garcinia mangostana Linn., was obtained by treating the dried ground pericarbs with hot water followed by ethanol precipitation (M fraction) . The extract was fractionated by anion exchange chromatography on a DEAE-cellulose column as MDE1-5 fractions . The fractions of MDE3 and MDE4 composed of mainly D-galacturonic acid and a small amount of neutral sugar (L-arabinose as the major one and L-rhamnose and D-galactose as the minor ones) were studied for immunopharmacological activities by phagocytic test to intracellular bacteria (Salmonella enteritidis) and nitroblue tetrazolium (NBT) and superoxide generation tests . The results showed that the number of S . enteritidis in cultured monocyte with extract of pericarb of mangosteen (MDE3) was killed . Activating score (mean +/- SD) of NBT test of 100 polymorphonuclear phagocytic cells were 145 +/- 78, 338 +/- 58, 222 +/- 73, 209 +/- 77, 211 +/- 63, 372 +/- 19, 369 +/- 20, 355 +/- 34 in normal saline control, phorbol myristate acetate (PMA), MDE3, MDE4, indomethacin (I), PMA + MDE3, PMA + MDE4 and PMA + I, respectively . Superoxide generation test was also done by color reduction of cytochrome c . Both MDE3 and MDE4 stimulate superoxide production . The number of S . enteritidis in cultured monocyte with extract of pericarb of mangosteen was killed . This paper suggests that polysaccharides in the extract can stimulate phagocytic cells and kill intracellular bacteria (S . enteritidis). West Afr J Med, 1997 Jul-Sep, 16(3), 195 - 8 Superficial Salmonella abscesses in two siblings with sickle cell diseases; Mansoury B et al.; Salmonella infection in sickle cell disease patients is generally well-known but presentation as superficial abscess is relatively uncommon . Two sisters aged 4 1/2 and 6 years presented with superficial subcutaneous abscesses that were caused by the same strain of Salmonella enteriditis group C . Despite in vitro susceptibility with a MIC of 0.03 microgram/ml and an adequate dosage of ciprofloxacin there was a relapse with widespread dissemination of the same organism in the younger sister who subsequently developed multiple osteolytic infections . Change of treatment to chloramphenicol produced a cure in both patients. Am J Vet Res, 1997 Oct, 58(10), 1125 - 31 Induction of gross and microscopic lesions of porcine proliferative enteritis by Lawsonia intracellularis; Joens LA et al.; OBJECTIVE: To evaluate experimental induction of porcine proliferative enteritis (PPE), using cell cultured Lawsonia intracellularis (ileal symbiont intracellularis), and to determine whether dexamethasone administration or age of the host or both affects susceptibility to L intracellularis infection . ANIMALS: Thirty-two 3- or 7-week-old pigs . PROCEDURES: Lawsonia intracellularis was extracted from tissue with lesions of PPE and was subcultured in a continuous Henle 407 cell line at 37 C under an atmosphere of 5% CO2 . Three- or 7-week-old pigs were inoculated orally with 100 ml of a 10-day-old cell culture preparation of the bacterium or infective intestinal homogenates . Control pigs were inoculated with uninfected Henle cells . Pigs were observed daily for clinical signs of infection and necropsied at death or at termination of the study . Lesions in the small and large intestines were recorded . RESULTS: Diarrhea was observed in pigs 4 to 7 days after inoculation with the pure culture agent or homogenates and lasted throughout the study period . Histologic lesions consistent with PPE were detected in pigs inoculated with pure culture . Intestinal lesions were absent in control pigs inoculated with uninfected Henle cells . Differences in lesions were not significant between treatment groups that varied in age or were receiving dexamethasone . Tissue specimens from pigs at necropsy were culture negative for Salmonella spp and Serpulina hyodysenteriae . CONCLUSION AND CLINICAL RELEVANCE: Gross and microscopic lesions typical of acute PPE were induced in pigs by use of a cell culture agent . Age differences and the stress induced by administration of dexamethasone had no effect on development of intestinal lesions. Am J Pathol, 1997 Oct, 151(4), 1163 - 9 Dephosphorylation of endotoxin by alkaline phosphatase in vivo; Poelstra K et al.; Natural substrates for alkaline phosphatase (AP) are at present not identified despite extensive investigations . Difficulties in imagining a possible physiological function involve its extremely high pH optimum for the usual exogenous substrates and its localization as an ecto-enzyme . As endotoxin is a substance that contains phosphate groups and is usually present in the extracellular space, we studied whether AP is able to dephosphorylate this bacterial product at physiological pH levels . We tested this in intestinal cryostat sections using histochemical methods with endotoxin from Escherichia coli and Salmonella minnesota R595 as substrate . Results show that dephosphorylation of both preparations occurs at pH 7.5 by AP activity . As phosphate residues in the lipid A moiety determine the toxicity of the molecule, we examined the effect of the AP inhibitor levamisole in vivo using a septicemia model in the rat . The results show that inhibition of endogenous AP by levamisole significantly reduces survival of rats intraperitoneally injected with E . coli bacteria, whereas this drug does not influence survival of rats receiving a sublethal dose of the gram-positive bacteria Staphylococcus aureus . In view of the endotoxin-dephosphorylating properties of AP demonstrated in vitro, we propose a crucial role for this enzyme in host defense . The effects of levamisole during gram-negative bacterial infections and the localization of AP as an ecto-enzyme in most organs as well as the induction of enzyme activity during inflammatory reactions and cholestasis is in accordance with such a protective role. Prev Med, 1997 Sep-Oct, 26(5 Pt 1), 599 - 602 Review--animal waste used as livestock feed: dangers to human health; Haapapuro ER et al.; Foodborne illness remains a common and serious problem, despite efforts to improve slaughterhouse inspection and food preparation practices . A potential contributor to this problem that has heretofore escaped serious public health scrutiny is the feeding of animal excrement to livestock, a common practice in some parts of the United States . In 1994, 18% of poultry producers in Arkansas collectively fed more than 1,000 tons of poultry litter to cattle, and the procedure is also common in some other geographic areas as a means of eliminating a portion of the 1.6 million tons of livestock wastes produced in the United States annually . While heat processing reliably kills bacterial pathogens, its use is limited by expense and other factors . Deep-stacking and ensiling are commonly used by farmers to process animal wastes, but the maximal temperatures achieved in stacked poultry litter are typically in the range of 43 to 60 degrees C (110 to 140 degrees F), below the inactivation temperatures of pathogenic salmonella and Escherichia coli species, and far below the USDA's recommended cooking temperatures of 71 to 77 degrees C (160 to 170 degrees F) for potentially manure-tainted meat products . In addition to the spread of potential pathogens, using animal wastes as feed presents the possibility that antibiotic-resistant bacteria may spread from one animal to another and that antibiotics or other chemicals may be passed between animals . Few research reports have addressed the safety of this practice, and those studies that have been published have generally been in controlled and artificial environments, rather than in on-farm conditions . Further microbiological studies are recommended to assess the extent of risk. Arzneimittelforschung, 1997 Sep, 47(9), 1052 - 5 Pharmacodynamic parameters of ofloxacin, tobramycin and ceftriaxone and their effect on the biological properties of salmonellae; Majtan V et al.; The postantibiotic effect and postantibiotic sub-MIC effect of ofloxacin (CAS 82419-36-1), tobramycin (CAS 32986-56-4) and ceftriaxone (CAS 73384-59-5) on two salmonella serotypes (S . typhimurium and S . enteritidis) were studied . The influence of postantibiotic effect and postantibiotic sub-MIC effect of the antibiotics on prophage induction of the lysogenic S . typhimurium strain and on Congo red binding by both serovars as indicator of their invasive ability was examined . The postantibiotic effect was induced by exposure of the bacteria to the 2x and 4x MIC concentrations of antibiotics studied for 0.5 h . The postantibiotic effects were different; ceftriaxone induced the longest postantibiotic effect against S . enteritidis, and the 4x MIC of tobramycin induced the longest postantibiotic effect against S . typhimurium . The postantibiotic sub-MIC effects lasted longer and in the case of subinhibitory concentrations of tobramycin on S . typhimurium and ceftriaxone on S . enteritidis did not allow any regrowth . The results showed that the postantibiotic effect and postantibiotic sub-MIC effect of ofloxacin induced a prophage of a lysogenic S . typhimurium strain, and the postantibiotic sub-MIC effects of tobramycin influenced Congo red binding by S . enteritidis cells. Clin Exp Immunol, 1997 Sep, 109(3), 431 - 8 Antagonistic effects of IL-4 and interferon-gamma (IFN-gamma) on inducible nitric oxide synthase expression in bovine macrophages exposed to gram-positive bacteria; Jungi TW et al.; Cytokine-mediated modulation of nitric oxide (NO) production by bacteria-stimulated bovine macrophages was studied . When Salmonella dublin, as a prototypic gram-negative organism, was used, NO generation was barely enhanced by recombinant bovine and ovine IFN-gamma, but was suppressed by IL-4 . Salmonella dublin-induced NO generation was not influenced by a panel of nine other cytokines . The panel included IL-1, tumour necrosis factor (TNF) and IFN-alpha, which are active in a similar mouse macrophage model . The tested cytokines were either homologous or known to interact with bovine cytokine receptors . Recombinant bovine and ovine IFN-gamma were the only cytokines which strongly enhanced NO synthesis by macrophages exposed to the gram-positive organism, Listeria monocytogenes . Listeria-induced NO generation was strongly suppressed by recombinant human and bovine IL-4, but not by IL-10 and transforming-growth-factor-beta . Thus, two cytokines characterizing a Th1 and a Th2 response up- and down-regulate, respectively, bacteria-induced NO generation in bovine macrophages, whereas nine other cytokines had little activity in this regard . This modulation was reflected in changes in the steady state levels of mRNA coding for inducible nitric oxide synthase . Combinations of IFN-gamma and IL-4 suggested that the relative proportion of these cytokines determined whether bacteria-induced NO generation was up- or down-regulated . At saturating IL-4 concentrations, stimulation of bacteria-induced NO generation in macrophages by T cell supernatants was solely dependent on IFN-gamma . This was shown by antibody neutralization experiments and by a close correlation between the capacity of supernatants to stimulate NO generation and the IFN-gamma content, as determined by immunoassay. Pediatr Cardiol, 1997 Nov-Dec, 18(6), 443 - 4 Right-sided endocarditis due to Salmonella typhi; du Plessis JP et al.; A case of right-sided endocarditis due to Salmonella typhi is described involving a native tricuspid valve in a child who was human immunodeficiency virus negative with no evidence of intravenous drug addiction . The patient had classic features of typhoid and tricuspid regurgitation without clinical evidence of bacterial endocarditis . Transthoracic echocardiography confirmed the tricuspid regurgitation . However, transesophageal echocardiography was necessary to demonstrate the vegetations affecting the tricuspid valve leaflets that made possible the diagnosis of endocarditis . The infection was cured with intravenous ceftriaxone and oral amoxicillin. Nature, 1997 Oct 16, 389(6652), 742 - 5 Lipopolysaccharide-binding protein is required to combat a murine gram-negative bacterial infection; Jack RS et al.; An invading pathogen must be held in check by the innate immune system until a specific immune response can be mounted . In the case of Gram-negative bacteria, the principal stimulator of the innate immune system is lipopolysaccharide (LPS), a component of the bacterial outer membrane . In vitro, LPS is bound by lipopolysaccharide-binding protein (LBP) and transferred to CD14--the LPS receptor on the macrophage surface--or to high-density lipoprotein (HDL) particles . Transfer to CD14 triggers an inflammatory response which is crucial for keeping an infection under control . Here we investigate how LBP functions in vivo by using LBP-deficient mice . Surprisingly, we find that LBP is not required in vivo for the clearance of LPS from the circulation, but is essential for the rapid induction of an inflammatory response by small amounts of LPS or Gram-negative bacteria and for survival of an intraperitoneal Salmonella infection. Cancer Res, 1997 Oct 15, 57(20), 4537 - 44 Tumor-targeted Salmonella as a novel anticancer vector; Pawelek JM et al.; There has been little investigation of bacteria as gene delivery vectors . Here, we demonstrate that genetically engineered Salmonella have many of the desirable properties of a delivery vector, including targeting of multiple tumors from a distant inoculation site, selective replication within tumors, tumor retardation, and the ability to express effector genes, such as the herpes simplex virus thymidine kinase (HSV TK) . When wild-type Salmonella were introduced into melanoma-bearing mice, the bacteria were found within the tumor at levels exceeding 10(9) per g, although as pathogens, they caused the death of the mice . However, when attenuated, hyperinvasive auxotrophic mutants were used, the tumor-targeting and amplification phenomena were retained, whereas their pathogenicity was limited . With such attenuated strains, the tumor:liver ratios ranged between 250:1 and 9000:1 . When these auxotrophs were inoculated i.p . into C57B6 mice bearing B16F10 melanomas, they suppressed tumor growth and prolonged average survival to as much as twice that of untreated mice . A plasmid containing the HSV TK gene with a beta-lactamase secretion signal was constructed that, when expressed, resulted in translocation to the periplasm and phosphorylation of the prodrug ganciclovir . Melanoma-bearing animals inoculated with HSV TK-expressing Salmonella showed ganciclovir-mediated, dose-dependent suppression of tumor growth and prolonged survival in addition to that seen with bacteria alone . The results demonstrate that attenuated Salmonella would be useful both for inherent antitumor activity and delivery of therapeutic proteins to cancer cells in vivo. Arthritis Rheum, 1997 Oct, 40(10), 1788 - 97 Crucial role of interleukin-10/interleukin-12 balance in the regulation of the type 2 T helper cytokine response in reactive arthritis; Yin Z et al.; OBJECTIVE: To investigate whether a predominant type 1 T helper (Th1) or Th2 cytokine pattern is present in the joints of patients with reactive arthritis (ReA), and whether the cytokine pattern can be modulated by cytokines or anticytokines . METHODS: Eleven patients with ReA following infection with either Chlamydia trachomatis, Yersinia enterocolitica, or Salmonella enteritidis were investigated for the presence of Th1/Th2 cytokines in the joints . Release of the bacteria-specific cytokines interferon-gamma (IFN gamma), tumor necrosis factor alpha (TNF alpha), interleukin-10 (IL-10), and IL-4 was measured in synovial fluid mononuclear cells (SFMC) using enzyme-linked immunosorbent assay and polymerase chain reaction . In the synovial membrane, secretion of IFN gamma and IL-4 was determined by immunohistologic analysis . Cytokine regulation was studied by adding cytokines and anticytokines to the cultures . RESULTS: Upon stimulation with specific bacteria, SFMC secreted low amounts of IFN gamma and TNF alpha, but high amounts of IL-10 . IL-10 was responsible for the suppression of IFN gamma and TNF alpha, as judged by the effect of adding either anti-IL-10 antibodies or exogenous IL-10 to these cultures . The addition of neutralizing anti-IL-12 to the cultures completely abolished the effects of anti-IL-10, suggesting that inhibition of the Th1-like cytokines by IL-10 is mediated through suppression of IL-12 synthesis . Exogenous IL-12 clearly enhanced IFN gamma and TNF alpha secretion . In the synovial membrane, a higher number of cells were positive for the Th2 cytokine IL-4, compared with the amount of IFN gamma-secreting cells . CONCLUSION: These data indicate that a Th2 cytokine pattern predominates in the joints of patients with ReA . Since Th1 cytokines are necessary for the elimination of ReA-associated bacteria, Th2 cytokines might contribute to bacterial persistence in the joint . Therefore, the IL-10/IL-12 balance appears to be crucial for regulation of the cytokine pattern in the joints of patients with ReA. J Biol Chem, 1997 Oct 17, 272(42), 26419 - 24 alpha-KDOase activity in oyster and synthesis of alpha- and beta-4-methylumbelliferyl ketosides of 3-deoxy-D-manno-octulosonic acid; Li YT et al.; Although alpha- and beta-linked 3-deoxy-D-manno-octulosonic acid (KDO) is found in lipopolysaccharides (LPSs) of Gram-negative bacteria, capsular polysaccharides of microorganisms, and plants, very little is known about its degradation . Using both thin-layer chromatography and the periodate-thiobarbituric acid reaction, we found that the hepatopancreas of oyster (Crassostrea virginica) contained an enzyme (alpha-KDOase) capable of releasing alpha-linked KDO from LPSs . To facilitate the studies of alpha-KDOase, we have carried out the synthesis of 4-methylumbelliferyl-alpha-KDO (alpha-KDO-MU) by conjugating the glycosyl chloride of the per-O-acetylated methylester of KDO with methylumbelliferone by the SN2 type reaction and the catalyzed phase-transfer . In both cases, the beta-anomer was obtained as the major product with a yield of about 80%, whereas the yield of alpha-anomer was only about 7% . Attempts to increase the yield of alpha-anomer were not successful . alpha-KDO-MU was used as substrate to follow the purification of alpha-KDOase from oyster hepatopancreas . The pH optimum for oyster alpha-KDOase was determined to be 4.5 using Re-LPS as substrate and 3.0 using alpha-KDO-MU as substrate . The enzyme was found to be stable in the pH range of 3-8 . This enzyme released KDO from different LPSs, including Re-LPS from Escherichia coli and Salmonella minnesota, Rd-LPS from S . minnesota, and de-O-acyl-Re-LPS (Kiang, J., Szu, S . C., Wang, L.X., Tang, M., and Lee, Y . C . (1997) Anal . Biochem . 245, 97-101). Cancer Res, 1997 Oct 1, 57(19), 4378 - 83 Polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin induce intrachromosomal recombination in vitro and in vivo; Schiestl RH et al.; Polychlorinated aromatic hydrocarbons such as polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are extremely stable and widely distributed environmental pollutants . These chemicals are animal carcinogens and probable human carcinogens, and TCDD is possibly one of the most potent toxins ever evaluated by the United States Environmental Protection Agency . Polychlorinated aromatic hydrocarbons score negatively in most genotoxicity assays, including the Ames (Salmonella) assay . Although their mechanism of toxicity is not well understood, they induce aryl hydrocarbon (AH) hydroxylases and bind to the AH receptor, which is believed to mediate toxicity . Here, we determine effects of polychlorinated aromatic hydrocarbons in genotoxicity assays that score for DNA deletions by intrachromosomal recombination in vivo and in vitro . In this study, TCDD, Aroclor 1221, and Aroclor 1260 induced deletions in vivo in the mouse embryo; Aroclor 1221 and Aroclor 1260 induced deletions in yeast . We also show that the induced deletion events did not correlate with induction of AH hydroxylase . None of the tested compounds induced CYP1A-associated ethoxyresorufin-O-deethylase activity in mouse embryos or in vitro . These results clearly demonstrate a genotoxic activity of polychlorinated aromatic hydrocarbons in vitro and in vivo, which is independent of induction of cytochrome P450 activity . Because genetic instability and deletions may be mechanistically involved in carcinogenesis, these results may encourage further research to determine whether such genotoxic mechanisms may be useful for cancer risk assessment of polychlorinated aromatic hydrocarbons. J Rheumatol, 1997 Oct, 24(10), 2047 - 50 Different course of reactive arthritis in two HLA-B27 positive brothers with fatal outcome in one; Yli-Kerttula T et al.; During an outbreak of Yersinia pseudotuberculosis III, one of two HLA-B27 positive brothers developed reactive arthritis (ReA), mild at first, but later severely destructive and ultimately fatal . The reactivation of ReA was possibly triggered by an oral polio vaccine . The cause of death was severe secondary amyloidosis . The other brother was exposed to the same Y . pseudotuberculosis strain but did not develop any disease during or after the outbreak . However, he later developed ReA due to a Salmonella infection, with a benign course. Vet Rec, 1997 Sep 20, 141(12), 297 - 9 Bacteriological monitoring of Salmonella enteritidis carrier birds after decontamination using enrofloxacin, competitive exclusion and movement of birds; Humbert F et al.; Two hundred and forty, four-week-old laying birds naturally infected with Salmonella enteritidis PT33 (Pasteur Institute phage typing system) were randomly divided twice (before and during the treatments) to obtain four separately housed groups of 60 birds and to study the efficacy of three decontamination treatments: enrofloxacin either with or without the movement of birds to a clean area, and enrofloxacin combined with movement of birds and a competitive exclusion treatment . The control group remained untreated . In each group contamination with S enteritidis was checked bacteriologically, every week from two months before until two months after the treatments began . All the samples taken from all the birds before the treatments began were S enteritidis-positive . After the treatments it was not possible to isolate salmonella either from the environment or from the faeces of the three treated groups . All the birds were humanely sacrificed at 22 weeks of age and samples of liver, spleen, ovaries and caeca were analysed for the presence of salmonella . The results demonstrated that although antibiotic therapy, the movement of birds into a clean house and competitive exclusion, either combined or not, had some efficacy in reducing infection levels, it was not possible to decontaminate all the birds completely. Gene, 1997 Sep 1, 196(1-2), 145 - 58 A ColE1-type plasmid from Salmonella enteritidis encodes a DNA cytosine methyltransferase; Ibanez M et al.; The multicopy plasmid pFM366 was isolated from a virulent Salmonella enteritidis strain and was found to code for DNA methylase activity (Ibanez and Rotger, 1993) . The present work was aimed at characterizing the genetic organization and functional features of this 5.6 kb plasmid . We found pFM366 almost identical to the plasmid P4 isolated from Shigella sonnei, that encodes the SsoII restriction-modification system (Karyagina et al., 1993), and related to other ColE1-type plasmids . Examination of these plasmids revealed a common organization which suggests they were the result of similar recombinational events . The cytosine methylase of pFM366 is nearly identical to M . SsoII, whereas the gene encoding the restrictase homologous to R . SsoII is truncated and its product is inactive . The expression of the cytosine methylase encoded by pFM366 is strongly affected by deletion of regions located upstream and downstream of its ORF, and is negatively controlled by the rpoS gene in Escherichia coli . The methylase activity encoded by pFM366 induces the SOS response, which could be responsible for the observed delay in the growth of E . coli. Gastroenterology, 1997 Oct, 113(4), 1214 - 23 Differential and regulated expression of C-X-C, C-C, and C-chemokines by human colon epithelial cells; Yang SK et al.; BACKGROUND & AIMS: Intestinal epithelial cells constitute a barrier between host and external milieu and can play a role in signaling the influx of leukocytes during the acute mucosal inflammatory response . To further explore this role, the regulated expression of twelve C-X-C, C-C, and C-chemokines by human colon epithelial cells was characterized . METHODS: Chemokine production was assessed in HT-29 and Caco-2 human colon epithelial cells that were infected with Salmonella dublin or stimulated with interleukin 1 alpha or tumor necrosis factor alpha and in freshly isolated human colon epithelial cells by quantitative reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assay . RESULTS: Expression of the neutrophil chemoattractants GRO-alpha, GRO-gamma, and interleukin 8 increased rapidly (2-3 hours) but transiently after infection or proinflammatory agonist stimulator . In contrast, expression of another neutrophil chemoattractant, epithelial cell-derived neutrophil activator 78, was delayed for 6-10 hours, and secretion continued to increase for 24 hours after infection . Among C-C chemokines known to chemoattract different leukocyte populations, monocyte chemotactic peptide 1 was rapidly expressed, whereas RANTES was up-regulated with delayed kinetics . Freshly isolated colon epithelial cells produced an array of chemokines similar to the cell lines, as well as macrophage inflammatory proteins 1 alpha and 1 beta . CONCLUSIONS: These data suggest that regulated chemokine production by epithelial cells results in temporal and spatial mucosal chemokine gradients that are important in both early and later phases of the mucosal inflammatory response. Southeast Asian J Trop Med Public Health, 1997 Mar, 28(1), 114 - 9 Characteristics of childhood diarrhea associated with enterotoxigenic Escherichia coli in Malaysia; Samuel S et al.; Amongst 107 diarrheal cases studied a bacterial agent was isolated from 71 (66%) cases of which 60 (85%) were due to a single agent and the remaining 11 (15%) were of mixed infections . Enterotoxigenic Escherichia coli (ETEC) was isolated from 65 cases . Other pathogens isolated included Salmonella spp, Shigella spp and rotavirus . There was a higher isolation rate of ETEC from females and rotavirus from males . The infection rate was found to higher for the 0-2 year age group as compared to the 3-5 year age group . Amongst the ETEC isolated the STa 2 toxotype was the predominant type. Southeast Asian J Trop Med Public Health, 1997 Mar, 28(1), 85 - 90 An institutional outbreak of Salmonella enteritidis in Singapore; Ng DP et al.; A large outbreak of food poisoning occurred in Singapore in March 1995 when a total of 188 inmates in an institution was taken ill . Salmonella enteritidis was isolated from the stool cultures of 35 inmates (16 symptomatic and 19 asymptomatic) . All the isolates were of the serotype profile 0:1, 9, 12 and H:g, m (antigen phase I); all were sensitive to ampicillin, ceftriaxone, chloramphenicol, co-trimoxazole and ciprofloxacin . Plasmid profile analysis and restriction enzyme fragmentation patterns (REFPs), as generated with EcoRI and HindIII, of a 60 kb plasmid obtained from these isolates were all identical, confirming that the outbreak resulted from a single source of infection . Stratified statistical analysis of food-specific attack rates strongly implicated imported canned luncheon pork consumed by the inmates on 26 March 95 as the single most probable cause of the food poisoning {p < 10(6), Mantel-Haenszel weighted odds ratio (OR) = 14.33; 95% confidence interval (CI) = 6.20-33.15} . The median incubation period of this outbreak was 19.3 hours and the median duration of illness was three days . The outbreak was rapidly brought under control through prompt implementation of epidemic control measures which comprised active search for diarrheal cases, rectal swabbing of asymptomatic inmates, isolation of those found to be infected, and maintenance of a high standard of personal, food and environmental hygiene. Southeast Asian J Trop Med Public Health, 1997 Mar, 28(1), 82 - 4 Pulsed-field gel electrophoresis as an epidemiologic tool in the investigation of laboratory acquired Salmonella typhi infection; Koay AS et al.; Strains of Salmonella typhi implicated in two separate cases of laboratory acquired infection from patients and the medical laboratory technologists who processed the patients' samples were analysed by pulsed-field gel electrophoresis . Although all four isolates were of bacteriophage type E1, PFGE was able to demonstrate that the strains responsible for the two laboratory acquired cases were not genetically related . The PFGE patterns of the isolates from the MLTs were found to be identical to those of the corresponding patients after digestion with restriction enzyme AvrII . This provided genetic as well as epidemiological evidence for the source of the laboratory acquired infections. Southeast Asian J Trop Med Public Health, 1997 Mar, 28(1), 73 - 81 Construction of specific DNA probe for the detection of Salmonella in food; Pilantanapak A et al.; The Salmonella specific DNA fragment from genomic DNA of S . typhimurium ATCC 23566 was cloned in E . coli and successfully used as a digoxigenin labeled probe for detecting the presence of Salmonella serotypes in both artificially contaminated food and natural contaminated food samples. FEMS Immunol Med Microbiol, 1997 Sep, 19(1), 95 - 100 Ontogeny of the phagocytic and bactericidal activities of turkey heterophils and their potentiation by Salmonella enteritidis-immune lymphokines; Lowry VK et al.; Heterophils, the functional equivalent to the mammalian neutrophil, are important mediators of natural resistance against invasive pathogens in poultry . Young poultry are susceptible to pathogens, such as Salmonella enteritidis, during the first week post-hatch . No studies have evaluated the ontogeny of heterophil function in turkeys during the first few weeks post-hatch . Previous studies from our laboratory have shown day-old poults were protected against S . enteritidis organ invasion following immunoprophylactic administration of chicken S . enteritidis immune lymphokines . Therefore, the objective in the present study was to characterize the development of phagocytosis and bacterial killing by turkey heterophils during the first 3 weeks of life and to compare the effect of immune lymphokines on the development of heterophil phagocytosis and killing during the first 3 weeks post-hatch . Both functional phagocytosis and killing activities were age-dependent events . During the first 1-7 days post-hatch, little functional activity was demonstrated which apparently is associated with susceptibility . Optimal heterophil phagocytosis and killing activities were reached 14-21 days post-hatch . Administration immune lymphokines significantly potentiated phagocytosis (P < 0.01) and killing (P < 0.001) by turkey heterophils . In fact, immune lymphokine administration to 1-7-day-old poults augmented phagocytosis and killing activities of heterophils equivalent to levels found in functionally mature 14-21-day-old poults . These results demonstrate the ontogeny of the functional activity of the turkey heterophil is an age-related phenomenon, with inefficient phagocytosis and killing during the first week post-hatch . Prophylactic administration of immune lymphokines significantly potentiated the functional activity of the heterophil poults during the first 3 weeks of life . Most importantly the administration of immune lymphokines enhanced the functional activity of heterophils from 1-7-day-old poults to levels comparable to that of an immunologically mature bird. Am J Physiol, 1997 Sep, 273(3 Pt 2), R1158 - 62 A sublethal dose of LPS to pregnant rats induces TNF-alpha tolerance in their 0-day-old offspring; Goto M et al.; The newborn has high mortality in septic shock . Induction of endotoxin tolerance may prevent endotoxic shock in the newborn . The present study showed that a small dose of Salmonella enteritidis lipopolysaccharide (S . ent . LPS), Rc mutant Escherichia coli lipopolysaccharide (J5 LPS), or tumor necrosis factor-alpha (TNF-alpha) given to pregnant rats on the 19th day of gestation induced endotoxin tolerance in their 0-day-old offspring . S . ent . LPS or J5 LPS injected into pregnant rats increased plasma endotoxin-like activity in dams, although not in their fetuses, and increased plasma TNF-alpha concentration in both dams and their fetuses . The endotoxin-tolerant newborn rats were also resistant to TNF-alpha . In those newborn rats, an LPS injection increased plasma TNF-alpha concentration and liver TNF-alpha mRNA abundance . These experiments showed that the endotoxin tolerance could be due to TNF-alpha tolerance . In conclusion, prenatal treatment of dams with a small dose of S . ent . LPS, J5 LPS, or TNF-alpha was beneficial in preventing endotoxic shock in the newborn. Infect Immun, 1997 Oct, 65(10), 4236 - 42 HLA-B27 modulates the survival of Salmonella enteritidis in transfected L cells, possibly by impaired nitric oxide production; Virtala M et al.; Reactive arthritis is triggered by certain microbes that cause primary infections mainly on the gastrointestinal or urogenital mucosa . The disease is strongly associated with HLA-B27 . Long persistence of causative microbes or their structures in the body has been thought to have an important role in the pathogenesis of reactive arthritis . This suggests that the elimination of the microbes causing reactive arthritis is ineffective or disturbed in HLA-B27-positive individuals developing this complication . We examined the role of the HLA-B27 antigen in microbe-host interaction in vitro by monitoring the invasion and intracellular survival of Salmonella enteritidis in mouse fibroblasts transfected with HLA-B27, HLA-B7, or beta2-microglobulin only . S . enteritidis invaded into all the three transfectants with the same efficiency . However, at 6 and 10 days after incubation, there were more living intracellular Salmonella organisms in HLA-B27 transfectants than in the other transfected cell lines (P < 0.05), suggesting that the bactericidal effect is impaired in these cells . Impaired NO production in HLA-B27-transfected cells was indicated as a possible mechanism, since the amount of nitrite in the supernatants of the Salmonella-infected HLA-B27-transfected cells was smaller than that in the supernatants of the Salmonella-infected HLA-B7- or beta2-microglobulin-transfected cells (P < 0.001) . The inhibition of NO synthesis by N-monomethyl-L-arginine resulted in impaired elimination of Salmonella also in HLA-B7and beta2-microglobulin-transfected cells . The inverse correlation between intracellular survival of Salmonella and the amount of nitrite detected in culture supernatants supports the hypothesis that the L-arginine-dependent NO pathway plays an important role in the murine fibroblast response against Salmonella . We suggest that a major histocompatibility complex class I antigen, HLA-B27, may contribute to the intracellular persistence of Salmonella by a mechanism which involves the NO pathway. Infect Immun, 1997 Oct, 65(10), 4094 - 9 Lipopeptides of Borrelia burgdorferi outer surface proteins induce Th1 phenotype development in alphabeta T-cell receptor transgenic mice; Infante-Duarte C et al.; Induction of the appropriate T helper cell (Th) subset is crucial for the resolution of infectious diseases and the prevention of immunopathology . Some pathogens preferentially induce Th1 or Th2 responses . How microorganisms influence Th phenotype development is unknown . We asked if Borrelia burgdorferi, the spirochete which causes Lyme arthritis, can promote a cytokine milieu in which T cells which are not specific for B . burgdorferi are induced to produce proinflammatory cytokines . Using alphabeta T-cell receptor transgenic mice as a source of T cells with a defined specificity other than for B . burgdorferi, we found that B . burgdorferi induced Th1 phenotype development in ovalbumin-specific transgenic T cells . Small synthetic lipopeptides corresponding to the N-terminal sequences of B . burgdorferi outer surface lipoproteins had similar effects . B . burgdorferi and its lipopeptides induced host cells to produce interleukin-12 . When the peptides were used in delipidated form, they did not induce Th1 development . These findings may be of pathogenic importance, since it is currently assumed that a Th2-mediated antibody response is protective against B . burgdorferi . Bacteria associated with reactive arthritis, namely, Yersinia enterocolitica, Shigella flexneri, and Salmonella enteritidis, had different effects . The molecular definition of pathogen-host interactions determining cytokine production should facilitate rational therapeutic interventions directing the host response towards the desired cytokine response . Here, we describe small synthetic molecules capable of inducing Th1 phenotype development. J Clin Microbiol, 1997 Oct, 35(10), 2487 - 91 Molecular epidemiology of two international sprout-borne Salmonella outbreaks; Puohiniemi R et al.; Sprout-borne Salmonella outbreaks in Finland have increased during the last 10 years . The latest two were caused by Salmonella enterica serovar Bovismorbificans (antigenic structure 6,8:r:1,5) in 1994 and S . enterica serovar Stanley (4,5, 12:d:1,2) in 1995 . In this study, the restriction fragment length polymorphism of genomic DNA after pulsed-field gel electrophoresis (PFGE) and antimicrobial resistance profiles of the outbreak and nonoutbreak strains were compared . In each separate outbreak, the PFGE patterns of the outbreak strains (40 strains of S . enterica serovar Bovismorbificans and 28 strains of S . enterica serovar Stanley) after digestion of genomic DNA with restriction enzyme XbaI were indistinguishable from each other but differed clearly from those of the nonoutbreak strains (26 strains of S . enterica serovar Bovismorbificans and 40 strains of S . enterica serovar Stanley) . The restriction enzyme XhoI did not differentiate the outbreak and nonoutbreak strains . The S . enterica serovar Stanley strains associated with the outbreak also had a unique antimicrobial resistance pattern, whereas all S . enterica serovar Bovismorbificans strains, both outbreak and nonoutbreak strains, were sensitive to all antimicrobial agents tested . Thus, the molecular typing confirmed that the S . enterica serovar Bovismorbificans outbreak isolates from humans and sprout salad were identical and strongly supported the epidemiological finding that S . enterica serovar Stanley outbreak isolates also originated from contaminated alfalfa seeds . It also confirmed that the sources of similar outbreaks in Sweden in 1994 caused by S . enterica serovar Bovismorbificans and in the United States in 1995 caused by S . enterica serovar Stanley and the source of the Finnish outbreaks were common. Eur J Pharmacol, 1997 Aug 27, 333(2-3), 181 - 6 Haemodynamic effects of dopexamine and nitric oxide synthase inhibition in healthy and endotoxaemic sheep; Waurick R et al.; Chronically instrumented awake healthy sheep (n = 6) received the synthetic catecholamine, dopexamine, during or without a background infusion of the nitric oxide synthase inhibitor . L-nitro-arginine-methylester (L-NAME) . Three days later, hypotensive-hyperdynamic circulation was induced and maintained by continuous infusion of Salmonella typhosa endotoxin (10 ng/kg per min) . After 24 h of continuous endotoxin infusion, the dopexamine L-NAME protocol was repeated . In healthy and endotoxaemic animals with and without nitric oxide synthase inhibition dopexamine caused the same haemodynamic changes: heart rate and cardiac output increased, mean arterial pressure and systemic vascular resistance decreased . L-NAME infusion induced normalisation of the hypotonic-hyperdynamic circulation in endotoxaemic animals . Dopexamine reduced some adverse effects of L-NAME treatment, like increased pulmonary vascular resistance and decreased oxygen delivery . In conclusion the haemodynamic effects of dopexamine are independent of the amount of nitric oxide production . Dopexamine may attenuate some of the adverse effects of nitric oxide synthase inhibition. Kansenshogaku Zasshi, 1997 Aug, 71(8), 788 - 92 {A case report--typhoid fever complicated with liver and gallbladder abscess, treated for long-time as fever of unknown origin}; Kawashima I et al.; A 25-year-old male admitted to Kawasaki municipal hospital with the diagnosis of typhoid fever . He had noticed high fever since one month ago, and had been treated with prednisolone with the diagnosis of fever of unknown origin in a hospital . Then he had admitted to St . Marianna University Hospital, and Salmonella Typhi had been detected from his blood and stool . On admission, multiple liver abscess were detected by abdominal ultrasonography . S . Typhi in bile was not eliminated with CP and AMPC, but he was successfully treated with cholecystectomy and the chemotherapy of LVFX . Abscess formation was found in the resected gall bladder wall . Typhoid nodule in the lymph node, liver or other organs is a well known pathological change in the typhoid fever . But abscess formation in the liver or other organs is rare . In this case, multiple abscess is characteristic and this cause is thought to be induced by the factors that the period from onset of typhoid fever to beginning of effective therapy was too long, and that steroid therapy was done without antibiotic therapy. Kansenshogaku Zasshi, 1997 Aug, 71(8), 745 - 50 {Application of arbitrarily primed polymerase chain reaction analysis to epidemiological study of Salmonella enterica serovar enteritidis}; Hanzaki O et al.; An arbitrarily primed polymerase chain reaction (AP-PCR) DNA profile was applied to epidemiological analysis of Salmonella enterica subsp . enterica serovar Enteritidis . A total 21 strains of S . Enteritidis isolated from 21 cases (10 cases of healthy persons, 7 cases of food poisoning outbreaks and 4 sporadic diarrhea cases), during the period between December 1991 and August 1996 in Wakayama City, were used . A total of 60 arbitrary primers (DNA oligomer (12) set, Wako) were screened with 4 S . Enteritidis strains of different cases . A-11, B-32, C-42 and C-45 primers were chosen . Plasmid DNA profiles, antimicrobial susceptibility patterns and phage types were also examined . The combination of these three methods resolved the collection into five groups (A to E) . And type C strains were found in 17 cases (81%) out of 21 cases . However, according to AP-PCR DNA profile, all 21 strains were classified into six groups (I to VI), and 17 type C strains were classified into three groups (III, IV and V) . Type IV was predominant in Wakayama City, and type C.IV was found in 15 cases (71%) . In conclusion, we considered that AP-PCR DNA profile using appropriate primers was an effective epidemiological marker. Kansenshogaku Zasshi, 1997 Aug, 71(8), 730 - 7 {Biochemical and molecular characterization of Salmonella serovar enteritidis phage type 4 isolated from food poisoning outbreaks in Tokyo}; Kusunoki J et al.; Since 1989, outbreaks of Salmonella ser . Enteritidis (S . Enteritidis) food poisoning have dramatically increased in Tokyo, and a total of 31 outbreaks has been reported in 1989 . Twenty-one of these 31 outbreaks were caused by S . Enteritidis PT34, but 8 outbreaks were caused by S . Enteritidis PT4 . After 1990 instead of SE PT34, food poisoning due to PT4, which was a very common phage type in the UK, has increased in Tokyo . Between 1989 and 1995, there were 144 food poisoning outbreaks caused by S . Enteritidis, and 64 of these outbreaks were by due to S . Enteritidis PT4, which was one of the main phage types in Tokyo . To characterize these strains of phage type (PT) 4,293 isolates from patients, and vehicle foods, eggs and environment in Tokyo were examined for plasmid DNA profiles, acid productivity from glycols (propylene and ethylene) and antimicrobial resistance patterns . Plasmid DNA was extracted by Kado's method, and analyzed by agarose gel electrophoresis . The acid productivity from propylene glycol or ethylene glycol were tested using Barsicow medium with 1% propylene glycol or ethylene glycol . Antimicrobial susceptibility to AM, CP, TC, SM, KM, NA, ST, FOM and NFLX was tested by the K-B disc method . The strains of PT4 were further subdivided into 9 types by those epidemiologic marker analysis . The prevalent pattern of PT4 strains was type A plasmid profile carrying only one plasmid (60 kb) and there were 2 kinds of antibiograms . One was SM resistant, while the other was susceptible . A total of 56 (87.5%) of 64 outbreaks was found to have been caused by these types of S . Enteritidis . Several kinds of egg-related foods were suspected as the vehicles of transmission among 24 outbreaks . Especially, in 5 outbreaks, S . Enteritidis strains were isolated both from patients and suspected food which were cooked with egg . This strongly suggests that these foods may be the potential source of infection in S . Enteritidis PT4 outbreaks. FEMS Microbiol Lett, 1997 Sep 15, 154(2), 207 - 13 Sequence analysis and distribution of an IS3-like insertion element isolated from Salmonella enteritidis; Collighan RJ et al.; The nucleotide sequence of a 3 kb region immediately upstream of the sef operon of Salmonella enteritidis was determined . A 1230 base pair insertion sequence which shared sequence identity (> 75%) with members of the IS3 family was revealed . This element, designated IS1230, had almost identical (90% identity) terminal inverted repeats to Escherichia coli IS3 but unlike other IS3-like sequences lacked the two characteristic open reading frames which encode the putative transposase . S . enteritidis possessed only one copy of this insertion sequence although Southern hybridisation analysis of restriction digests of genomic DNA revealed another fragment located in a region different from the sef operon which hybridised weakly which suggested the presence of an IS1230 homologue . The distribution of IS1230 and IS1230-like elements was shown to be widespread amongst salmonellas and the patterns of restriction fragments which hybridised differed significantly between Salmonella serotypes and it is suggested that IS1230 has potential for development as a differential diagnostic tool. Int J Food Microbiol, 1997 Jul 22, 37(2-3), 241 - 4 A comparison of procedures involving single step Salmonella, 1-2 Test, and modified semisolid Rappaport-Vassiliadis medium for detection of Salmonella in ground beef; Afflu L et al.; Procedures involving Single Step Salmonella (SSS), 1-2 Test, and Modified Semisolid Rappaport-Vassiliadis Medium (MSRV) were compared for their speed and sensitivity in detection of Salmonella in ground beef contaminated with one isolate of each of five Salmonella serotypes . Inocula of 10, 10(2) and 10(3) CFU/g of ground beef were used . When pre-enrichment in buffered peptone water and selective enrichment in tetrathionate broth were used, SSS and MSRV detected all five species of Salmonella at all levels of contamination, whereas the 1-2 Test was positive in 0, 12, and 15 of 15 tests at 10, 10(2) and 10(3) CFU/g, respectively . When only pre-enrichment was used, the results with MSRV were unchanged but the SSS test failed to detect S . typhimurium . Thus, with pre-enrichment the MSRV and SSS procedures were equally sensitive and both produced a result on the third day . The 1-2 Test was less sensitive and slower, with results available on day-4 . The MSRV protocol was best overall. Int J Food Microbiol, 1997 Jul 22, 37(2-3), 183 - 8 Assay of Salmonella in enrichment cultures of foods, feeds and environmental samples by the polymyxin-cloth enzyme immunoassay; Blais BW et al.; A variety of foods, animal feeds and environmental samples were analyzed for the presence of Salmonella using the polymyxin-cloth enzyme immunoassay (p-CEIA) system . Salmonella lipopolysaccharide (LPS) antigens were captured from test samples on polymyxin-coated polyester cloth, followed by immunoenzymatic detection of bound antigens using a monoclonal antibody recognizing an LPS common core oligosaccharide . Dairy and egg products, animal feeds and environmental samples from food processing plants were pre-enriched for 24 h, followed by selective enrichment for a further 24 h in either tetrathionate brilliant green (TBG), selenite cystine (SC) or brain-heart infusion broth containing 0.5% yeast extract, 0.5% cholate and 0.3% selenite (BYCS) . The samples were assayed by the p-CEIA after each stage of enrichment . After selective enrichment, the p-CEIA gave results which were in complete agreement with the standard culture technique in the analysis of all foods examined . On the other hand, a combination of selective enrichment and the p-CEIA out-performed the Modified Semi-Solid Rappaport Vassiliadis (MSRV) method in screening pre-enrichment cultures of feeds and environmental samples . Use of the new selective medium BYCS prior to performing the p-CEIA gave the highest recovery of Salmonella from feeds and environmental samples. Eur J Biochem, 1997 Aug 15, 248(1), 217 - 24 Lipopolysaccharide-binding proteins and their involvement in the bacterial clearance from the hemolymph of the silkworm Bombyx mori; Koizumi N et al.; Proteins having the ability to bind to Escherichia coli K12W3110 (rough (R) mutant) were isolated and purified by affinity precipitation from the larval hemolymph of the silkworm Bombyx mori . These proteins were found to consist of two components with molecular masses of 43 kDa and 40 kDa by SDS/PAGE . They bound to all E . coli R mutants (Ra, Rb1, Rc, Rd1 and Re) and Salmonella minnesota R mutants . However, they did not bind to smooth types of the above bacteria . They bound to both lipopolysaccharide(LPS)-coated and lipid-A-coated microtiter plates and have similar dissociation constants for LPS and lipid A . This indicates that the binding proteins recognize the lipid A portion of LPS and thus, we have named these proteins BmLBP (B . mori LPS-binding proteins) . We also found that BmLBP participated in the clearance of E . coli cells injected into the body cavity of the silkworm. AIDS Res Hum Retroviruses, 1997 Sep 20, 13(14), 1187 - 94 Induction of mucosal and systemic responses against human immunodeficiency virus type 1 glycoprotein 120 in mice after oral immunization with a single dose of a Salmonella-HIV vector; Wu S et al.; Previous studies from our group showed that a Salmonella-HIV vector vaccine that expressed recombinant HIV-1 envelope protein gp120 stably in the vector cytoplasm elicited type 1 helper T cell (Th1) responses to gp120 . Despite the promise of such vaccines, a major limitation in their use was that multiple immunizations were required to elicit even small responses . For this reason, we sought a modified vector configuration that would induce more potent gp120-specific T cell responses exhibiting a broader spectrum of effector functions after a single inoculation . In this article we describe the construction and immunogenicity of a Salmonella-HIV vector that displays a truncated derivative of HIV-1(IIIB) envelope in the periplasm of the vector . A single oral dose of this Salmonella vector, called H683(pW58-asd+), generated a gp120-specific proliferation response in the spleen 14 days after immunization . In agreement with our previous findings, the gp120-specific splenic CD4+ T cells elicited by H683(pW58-asd+) displayed a Th1 phenotype; however, gp120-specific splenic CD4+ Th2 cells were also evident . In addition, this strain induced strong gp120-specific IgA antibody-secreting cell (ASC) responses in the intestinal lamina propria and mesenteric lymph nodes . As many as 2% of the total lamina propria and mesenteric lymph node IgA ASCs were found to be specific for gp120 28 days after a single oral dose of H683(pW57-asd+) . Because the proliferative response following a single dose of H683(pW58-asd+) was comparable to that seen previously after three doses of an analogous construct expressing recombinant gp120 in the cytoplasm, these observations suggest that Salmonella-vectored secreted HIV-1 antigens elicit higher T cell responses than their cytoplasmically bound analogs. Z Naturforsch {C}, 1997 Jul-Aug, 52(7-8), 413 - 20 New botrydial sesquiterpenoids from Hymenoscyphus epiphyllus; Thines E et al.; Four new botrydial derivatives, hymendial (1), 7 alpha-hydroxydihydrobotrydial (2), 7 alpha-hydroxy-10-O-methyldihydrobotrydial (4), and 7 alpha-acetoxy-15 alpha-methoxy-10-O-methyl-dihydrobotrydial (5) were isolated together with dihydrobotrydial (3) from the culture fluid of the ascomycete Hymenoscyphus epiphyllus . In addition, cytochalasin H (6a), 18-deoxycytochalasin H (6b) and (+)-mellein (7) were produced by this fungus . Hymendial (1), possessing an alpha, beta-unsaturated dialdehyde functionality, exhibits antimicrobial and cytotoxic activities and is mutagenic in the Ames Salmonella assay. Microb Drug Resist, 1997 Fall, 3(3), 263 - 6 Increase in multiple antibiotic resistance in nontyphoidal salmonellas from humans in England and Wales: a comparison of data for 1994 and 1996; Threlfall EJ et al.; The incidence of multiple drug resistance (to four or more antimicrobials) in salmonellas from humans in England and Wales in 1996 has been compared with corresponding data for 1994 . For Salmonella enteritidis multiple resistance has remained rare, although a high proportion of isolates of phage type 6A have shown resistance to ampicillin . For S . typhimurium multiple resistance has continued to increase, with 81% of isolates now multiresistant . Of particular importance in S . typhimurium has been the continued epidemic of multiresistant DT 104 and the increasing occurrence of strains of this phage type with additional resistance to trimethoprim and/or ciprofloxacin . For S . virchow, a 10% increase in multiple resistance is mainly concentrated in two phage types common in returning travellers . For S . hadar, there has been a substantial increase in the incidence of multiple resistance with over 50% of isolates now multiresistant . Substantial increases in the incidence of resistance to ciprofloxacin in multiresistant S . typhimurium DT 104, S . virchow, and S . hadar since 1993, when the fluoroquinolone antibiotic enrofloxacin was licensed for veterinary use in the UK, are of particular concern. Behring Inst Mitt, 1997 Feb, (98), 376 - 89 Targeting of mucosal vaccines to Peyer's patch M cells; Frey A et al.; Transepithelial transport of antigens and pathogens is the first step in the induction of a mucosal immune response . In the intestine, the delivery of antigens across the epithelial barrier to the underlying lymphoid tissue is accomplished by M cells, a specialized epithelial cell type that occurs only in the lymphoid follicle-associated epithelium . Selective and efficient transport of antigen by M cells is considered an essential requirement for effective mucosal vaccines . Therefore, particulate antigen formulations are currently being developed to take advantage of the capacity of M cells to endocytose particles . Based on pathogens that exploit the M cell as an invasion route into the body, live mucosal vaccines have been designed using genetically-engineered, attenuated strains of pathogens such as poliovirus and Salmonella . In an alternative approach, antigens are coupled to or encapsulated in particulate synthetic carriers . To enhance binding and uptake of such nonviable vectors, ligands are being attached which direct the vaccine particle to receptors on the M cell surface. Behring Inst Mitt, 1997 Feb, (98), 24 - 32 Antigen sampling by epithelial tissues: implication for vaccine design; Kraehenbuhl JP et al.; Mucosal surfaces of the respiratory, digestive and urogenital tracts are covered by a specialized epithelium which constitutes an efficient physical barrier against environmental pathogens . These surfaces differ greatly in their cellular organisation and in antigen sampling . In stratified epithelia, professional antigen-presenting cells, the dendritic cells or Langerhans cells, are intimately associated with the epithelial barrier and take up samples of foreign material from the external environment which they transport to local or distant organized lymphoid tissues . In simple epithelia highly specialised cells, the so-called M cells, sample foreign material and microorganisms and deliver them by transepithelial transport from the lumen to the underlying organized lymphoid tissue (MALT) . The interaction of lymphocytes with the follicle-associated epithelium (FAE) is responsible for the loss of digestive functions and the acquisition of transepithelial transport activity . The three way interaction of epithelium, lymphoid cells, and microorganisms seen in the FAE which controls the formation of MALT provides a dramatic demonstration of the phenotypic plasticity of the intestinal epithelium and probably of all simple epithelia . We have shown that all mucosal surfaces, covered by stratified or simple epithelia are able to sample and transport live recombinant bacterial vaccines, which elicit systemic and local immune responses against the carrier and the foreign antigen . In gut and nasal-associated lymphoid tissue, Salmonella are taken up by dendritic cells which form a dense cellular network in the dome regions of MALT . Targeting bacterial vaccine candidates to dendritic or M cells is likely to facilitate their sampling by epithelial tissues and to contribute to strong mucosal and systemic immune responses. Behring Inst Mitt, 1997 Feb, (98), 197 - 211 Bacterial antigen delivery systems: phagocytic processing of bacterial antigens for MHC-I and MHC-II presentation to T cells; Svensson M et al.; Using an in vitro model system we have studied parameters of both bacteria and antigen presenting cells that influence peptide presentation by murine major histocompatibility complex class II (MHC-II) and class I (MHC-I) molecules . To study MHC-II presentation, the HEL (52-61) epitope, which binds the murine MHC-II molecule I-Ak, was expressed as the cytoplasmic Crl-HEL fusion protein in S . typhimurium . When murine peritoneal macrophages mediated phagocytic processing of S . typhimurium expressing Crl-HEL, HEL (52-61) was processed and presented on I-Ak more efficiently from heat-killed S . typhimurium than from viable bacteria, and from a rough LPS strain compared to its isogenic smooth LPS counterpart, most likely due to enhanced phagocytosis of the rough LPS strain . Macrophages also processed phoP S . typhimurium strains with greater efficiency for peptide presentation by I-Ak than wild type bacteria while Salmonella constitutively expressing phoP were processed for peptide presentation by I-Ak less efficiently than wild type Salmonella . We have also shown that macrophage phagocytosis of E . coli or S . typhimurium results in presentation of bacterial antigens by MHC-I molecules . To investigate the role of post-Golgi MHC-I molecules in this presentation pathway, peritoneal macrophages from TAP1-/- mice, which are deficient in presenting endogenous antigens on MHC-I and lack significant surface MHC-I expression, were co-incubated with bacteria containing the 257-264 epitope from ovalbumin {OVA(257-264)}, which binds the murine class I molecule Kb . Peritoneal macrophages from TAP1-/-/ mice could process bacteria expressing the OVA epitope for recognition by epitope-specific T hybridoma cells . This processing and presentation was reduced in efficiency between three to 100 fold compared to C57BL/6 macrophages, depending on the protein harbouring the OVA (257-264) epitope (Crl-OVA or native OVA) . This suggests that the protein context of the OVA (257-264) epitope influences the extent of TAP-independent processing for MHC-I presentation . In addition, we show that murine bone marrow-derived dendritic cells can phagocytose and process viable gram negative bacteria for peptide presentation on MHC-I and MHC-II; inhibition studies showed that acidic compartments in dendritic cells are required for this presentation . These results suggest that dendritic cells may be potential antigen presenting cells used in eliciting specific immune responses against bacteria. Behring Inst Mitt, 1997 Feb, (98), 143 - 52 Oral bacterial vaccine vectors for the delivery of subunit and nucleic acid vaccines to the organized lymphoid tissue of the intestine; Pascual DW et al.; Bacterial vaccine vectors have the potential to deliver a number of antigens from bacterial, protozoan and viral pathogens . To further develop the utility of bacterial vaccine vectors we are currently evaluating three model systems: 1 . A Salmonella-ETEC Vaccine Vector; 2 . A Salmonella-HIV Vaccine Vector, and 3 . Novel Live Bacterial Nucleic Acid Vaccine Vectors . Through our studies, and those of others, significant progress has been made toward bacterial vaccine vector systems that effectively deliver subunit and nucleic acid vaccines to the organized lymphoid tissue of the intestine . The practical reality of these findings is discussed. Behring Inst Mitt, 1997 Feb, (98), 135 - 42 Expression and immune response to foreign epitopes in bacteria . Perspectives for live vaccine development; Charbit A et al.; We previously developed a general procedure which allows the genetic coupling of a chosen foreign linear epitope in different regions of a carrier protein . By using as carriers, two bacterial envelope proteins, the LamB and MalE proteins of E . coli K12, we were able to express the same epitope in different sites of the two proteins and in different compartments of the bacteria . This allowed us to analyze the influence of the localization in E . coli cells of a foreign B-cell epitope on the induction of specific antibody responses, and the role of the molecular environment on the immunological properties of foreign B- or T-cell epitopes, using either purified hybrid proteins or live recombinant bacteria . Several LamB and MalE hybrid proteins were expressed in the aroA attenuated strain of S . typhimurium, SL3261 . Immunizations of mice with live recombinant bacteria by the intravenous route showed that it was possible to induce humoral responses against inserted foreign sequences . In order to improve the in vivo stability of the plasmids carrying the different contructions, and to increase the amounts of recombinant LamB and MalE hybrid proteins expressed in vivo, the LamB and malE genes were placed under the control of the anaerobically inducible pnirBpromoter control . The genetic factors susceptible of influencing the immune response to recombinant Salmonella in mice were also studied. J Biotechnol, 1997 Aug 28, 56(3), 191 - 203 Expression and immunogenicity of V3 loop epitopes of HIV-1, isolates SC and WMJ2, inserted in Salmonella flagellin; Cattozzo EM et al.; Synthetic oligonucleotides corresponding to specific V3 loop portions of two HIV-1 isolates, SC and WMJ2, were expressed in the flagella of a Salmonella live-vaccine strain . Expression of the inserted epitopes in flagellin and their exposure at the surface of flagellar filaments were shown by immunoblotting and immunogold labeling with anti-flagellin (Salmonella d) and anti-HIV-1(IIIB) V3 loop peptide sera . Live recombinant Salmonella strains expressing either one of the two V3 loop inserts were administered intraperitoneally to BALB/c mice . All these animals developed antibodies specific for the heterologous glycoprotein 120 (gp120) of HIV-1 MN strain, as detected by enzyme-linked immunosorbent assays (ELISA), two of the sera had neutralizing activity against the heterologous HIV-1 MN strain . Moreover, oral administration of the live Salmonella recombinant strains to mice evoked specific IgA directed against gp120. Mol Plant Microbe Interact, 1997 Sep, 10(7), 926 - 8 The activity of lipid A and core components of bacterial lipopolysaccharides in the prevention of the hypersensitive response in pepper; Newman MA et al.; Pre-treatment of leaves of pepper (Capsicum annuum) with lipopolysaccharide (LPS) preparations from enteric bacteria and Xanthomonas campestris could prevent the hypersensitive response caused by an avirulent X . campestris strain . By use of a range of deep-rough mutants, the minimal structure in Salmonella LPS responsible for the elicitation of this effect was determined to be lipid A attached to a disaccharide of 2-keto-3-deoxyoctulosonate; lipid A alone and the free core oligosaccharide from a Salmonella Ra mutant were not effective . For Xanthomonas, the core oligosaccharide alone had activity although lipid A was not effective . The results suggest that pepper cells can recognize different structures within bacterial LPS to trigger alterations in plant response to avirulent pathogens. Zh Mikrobiol Epidemiol Immunobiol, 1997 May-Jun, (3), 76 - 81 {The unknown functions of heterologous antigens of different origins}; Nikolaeva AI; After a single injection of 125I-labeled erythrocytic antigen to mice, the protein determinants of this antigen were found in nuclear RNP of B lymphocytes of the immune animals . On day 2 after the injection of Shigella sonnei phase I LPS (also containing protein) to mice hybridization between total RNA isolated from B lymphocytes and 32P-labeled plasmid pSS 120, controlling the synthesis of the S . sonnei phase I antigen, was observed . On day 1 after immunization no hybridization between cell RNA and plasmid pSS 120 occurred . Besides, no hybridization of plasmid DNA with the RNA of nonimmune animals or with RNA, obtained on day 3 after the injection of Salmonella kentucky LPS to mice, was observed . The signal indicating the occurrence of hybridization between the RNA of immune B lymphocytes and plasmid pSS 120 appeared on day 2 and increased on days 3 and 5 after the injection of the antigen . This was seemingly indicative of the accumulation of new nucleotide sequences, complementary to the gene controlling the synthesis of the heterologous antigen which caused immune response, in immune B lymphocytes. G Chir, 1997 Apr, 18(4), 222 - 8 {Non-parasitic splenic cysts}; Teneriello FL et al.; Nonparasitic cysts of the spleen are uncommon and often result from blunt abdominal trauma . Nonsurgical management of blunt splenic injuries increases the number of observations of the post-traumatic cysts . Complications (infection, rupture and hemorrhage) are lifethreatening, difficult to diagnose and require urgent surgical management . Until recently, splenectomy has been the primary choice of treatment of these cysts . Small (< 4 cm) asymptomatic post-traumatic pseudocysts stand a reasonable chance of involution with time (3-36 months) and so may be initially observed . Splenic preservation by partial splenectomy, enucleation or by marsupialization is actually recommended in children when technically feasible . Splenectomy is required for voluminous, central, multifocal cysts, in the presence of complications and in the adults with low immunologic risk . The Authors report 5 cases of large cysts successfully treated by splenectomy with one 12-year-old girl treated in emergency for infection by Salmonella. Vaccine, 1997 Aug-Sep, 15(12-13), 1319 - 22 Expression of the serine rich Entamoeba histolytica protein (SREHP) in the avirulent vaccine strain Salmonella typhi TY2 chi 4297 (delta cya delta crp delta asd): safety and immunogenicity in mice; Zhang T et al.; Infection by the intestinal protozoan parasite Entamoeba histolytica remains a significant threat to health in much of the world . Here we describe the successful expression of the serine rich Entamoeba histolytica protein (SREHP), a protective antigen of ameba, in an attenuated vaccine strain Salmonella typhi TY2 chi 4297 (delta cya delta crp delta asd) . The attenuation of S . typhi TY2 chi 4297 was not altered by expression of the SREHP-maltose binding protein (MBP) fusion protein and mice parenterally vaccinated with S . typhi TY2 chi 4297 expressing SREHP-MBP developed serum anti-amebic and anti-LPS antibodies . S . typhi TY2 chi 4297 expressing SREHP-MBP represents a prototype combination vaccine designed to prevent both amebiasis and typhoid fever. Lupus, 1997, 6(7), 610 - 2 Fatal amoebic colitis in a patient with SLE: a case report and review of the literature; Tai ES et al.; Colitis in systemic lupus erythematosus (SLE) poses a diagnostic challenge as clinical, radiological and laboratory findings are often non-specific . Fulminant amoebic colitis is a rare cause of death in SLE . Early diagnosis coupled with timely surgery can reduce the mortality . The demonstration of haematophagous trophozoites in the stool is diagnostic but insensitive . Early endoscopy with adequate specimen collection is an important part of the diagnosis . Serology is both sensitive and specific but can take up to 2-4 weeks for seroconversion making it less useful in a disease that takes a rapid downhill course if treated inappropriately . We report a fatal case of colitis in a patient with SLE due to invasive amoebiasis which was complicated by Salmonella bacteraemia, disseminated intravascular coagulation, acute oliguric renal failure and adult respiratory syndrome . We also reviewed the literature on the clinical features and diagnosis of fulminant amoebic colitis . Amoebic colitis, although rare, should be considered in the differential diagnosis of lupus patients with colitis. Clin Diagn Lab Immunol, 1997 Sep, 4(5), 587 - 91 Field evaluation of an immunoglobulin G anti-F1 enzyme-linked immunosorbent assay for serodiagnosis of human plague in Madagascar; Rasoamanana B et al.; Bacteriological isolation of Yersinia pestis is the reference test for confirming plague infection, but recovery of the pathogen from human samples is usually very poor . When the etiology of the disease cannot be bacteriologically confirmed, it may be useful to possess alternative tests such as detection of specific circulating antibodies to help guide the diagnosis . In the present study, the immunoglobulin G (IgG) anti-F1 enzyme-linked immunosorbent assay (ELISA) has been applied to various human sera to evaluate its large-scale applicability in the high-endemicity plague foci of Madagascar . The sensitivity of the test was found to be 91.4%, and its specificity was 98.5% . The positive and negative predictive values were 96 and 96.6%, respectively . Seroconversion was observed on day 7 after onset of the disease . Patients with a positive ELISA result could be separated into high (82%) and low (18%) IgG anti-F1 responders . Cross-reactions with eight other infectious diseases prevalent in Madagascar were scarce and were found in 1 of 27 Mycobacterium tuberculosis-, 3 of 34 Schistosoma haematobium-, and 1 of 41 Salmonella-infected patients . Finally, the efficiency of the IgG anti-F1 ELISA was evaluated during the Mahajanga, Madagascar, plague outbreak of 1995 . When the number of ELISA-positive patients was added to the number of bacteriologically confirmed and probable cases, the number of positive patients was increased by 35% . In conclusion, although it does not replace bacteriology, IgG anti-F1 ELISA is a useful and powerful tool for retrospective diagnosis and epidemiological surveillance of plague outbreaks. Ann Vasc Surg, 1997 Sep, 11(5), 533 - 5 Infectious aortitis due to penicillin-resistant Streptococcus pneumoniae; Maclennan AC et al.; Infectious aortitis is uncommon and typically affects elderly immunocompromised men, with a Salmonella or Staphylococcal infection of an atheromatous or aneurysmal aorta . We present a fit young man who developed infectious aortitis with peripheral embolization due to a penicillin-resistant Streptococcus pneumoniae bacteremia. Ann Vasc Surg, 1997 Sep, 11(5), 453 - 63 Infected aneurysms of the infrarenal abdominal aorta: diagnostic criteria and therapeutic strategy; Sessa C et al.; From 1976 to 1994 we performed surgical treatment of 18 infected aneurysms of the infrarenal abdominal aorta . The aneurysm had ruptured in nine patients: into the retroperitoneum in six patients, and into an adjacent structure in three patients (duodenum, inferior vena cava, left renal vein) . Two patients had an associated spondylitis . Four patients were in shock at the time of surgical treatment . Six patients (including four patients with Salmonella infection and two patients with spondylitis) had positive preoperative blood cultures . Salmonella was the most common microorganism (27%) . Anaerobes accounted for 16% . In situ replacement was performed in 13 patients including three procedures performed under emergency conditions with frank purulent infection . Extraanatomic bypass was performed in five patients . Early postoperative death occurred in two patients (11%) due to septic complications (rupture of aortic anastomosis in one patient and rupture of aortic stump in one patient) . All surviving patients underwent prolonged antibiotic therapy for at least 6 weeks . Overall mortality secondary to infected aneurysm was 16% . Infection of the aortic graft occurred in four patients (38%) including two patients with Salmonella infection and one patient with spondylitis . One patient developed a false anastomotic aneurysm 6 months postoperatively and was treated by in situ arterial allograft replacement . Postoperative blood cultures were positive in two patients presenting spondylitis and infection of the aortic prosthesis occurred in one of these patients . In addition to rupture, poor prognostic factors included spondylitis and Salmonella infection that were found to greatly enhance the risk of postoperative graft infection following in situ reconstruction. Environ Health Perspect, 1997 Sep, 105(9), 940 - 8 Allergic contact sensitizing chemicals as environmental carcinogens; Albert RE; Chemicals that were bioassayed by the National Toxicology Program (NTP) and that also produce allergic dermatitis (ACD) in humans were evaluated for their tumorigenic characteristics . The impetus for the study was that most contact sensitizers, i.e., those that produce ACD, and genotoxic carcinogens are chemically similar in that they are electrophilic, thereby producing adducts on macromolecules including protein and DNA . This similarity in chemical behavior suggests that many contact sensitizers might be environmental carcinogens . All of the published NTP bioassays by early 1996 that had both genotoxicity and carcinogenicity studies were included in this analysis . The NTP chemicals had been chosen for bioassay without regard to their ability to produce ACD . Of the 209 chemicals that were bioassayed, there were 36 (17%) that were known to be human contact sensitizers; about half of these were positive on tumor bioassays . The contact sensitizers differed from the NTP sample as a whole by having a proportionately larger number of nongenotoxic chemicals by the Ames Salmonella assay, presumably because more of them were selected on the basis of widespread usage rather than structural resemblance to known carcinogens . Compared to the nongenotoxic chemicals, the genotoxics were stronger carcinogens in that they had a higher incidence of positive tumor bioassays, with twice the number of organs in which tumors were induced . The nongenotoxic chemicals had a preference for tumor induction in parenchymal tissues in contrast to epithelial tissues . The contact sensitizers showed essentially the same characteristics as the whole NTP sample when stratified according to genotoxicity . Judging by the chemicals that were chosen primarily for their widespread use rather than for their structural resemblance to carcinogens, the addition of a test for contact sensitization to the Ames test as a screening tool would increase the tumorigenic detection efficiency by about 40% because of the nongenotoxic tumorigens . A ballpark estimate suggests that there could be several thousand contact sensitizers for humans in commercial use that are rodent tumorigens. Biol Chem, 1997 Aug, 378(8), 815 - 9 RAGged repair: what's new in V(D)J recombination; Hagmann M; Antigen-specific immunity is due to the generation of a multitude of both immunoglobulins and T-cell receptors through a process designated V(D)J recombination . In vitro reconstitution of this system has taught us a great deal about the molecular mechanism underlying this site-specific recombination process . Hence, it became obvious that the initial steps of the reaction are carried out by the lymphocyte-specific proteins RAG1 and RAG2 (recombination-activating genes), with the help of members of the high mobility group protein family of DNA-binding proteins, HMG1 or HMG2 . Structural resemblance between RAG1 and a prokaryotic recombinase, the Salmonella Hin Recombinase, together with mechanistic similarities between V(D)J recombination and bacterial transposition reactions, make it likely that these different processes have evolved from a common ancestral recombination system . The second step in V(D)J recombination is catalysed by the ubiquitous DNA double-strand break repair machinery . The link between V(D)J recombination and double-strand break repair was established through some mutational complementation groups, including the murine SCID mutation (severe combined immunodeficiency), which were shown to be defective in both V(D)J recombination and double-strand break repair . The multisubunit DNA-dependent protein kinase appears to be a key player in these processes . Thus, from an evolutionary point of view, antigen-specific immunity in mammals, e.g., humans and mice, appears to be the result of an evolutionary combination of two unrelated systems involved in DNA metabolism. Gene, 1997 Aug 11, 195(1), 93 - 100 Sequence comparison of the genes for immunity, DNA replication, and cell lysis of the P22-related Salmonella phages ES18 and L; Schicklmaier P et al.; Complementation and hybridization experiments with the generalized transducing Salmonella phages P22, ES18 and L revealed strong similarity between the phages L and P22; the genome of ES18 shows a mosaic structure . About half of its genome, including the early genes, is similar or completely homologous to P22; the other half of the morphologically different ES18 does not show any similarity to P22 nor to E . coli phage lambda . Sequence comparison of the early genes has confirmed that the C-immunity region of ES18 is identical with that of P22, whereas the same region of phage L shows poor (repressor gene) or no similarity . The 5'-terminus of the DNA replication gene 12 of ES18, however, is homologous to the same section of gene O of phage lambda . The lysis genes of ES18 again are identical to those of P22; only gene 15 is mosaic-like and has more similarity to gene Rz of phage lambda . These results will be discussed in terms of the theory of modular genome organization. Haematologica, 1997 Jul-Aug, 82(4), 415 - 9 Bacteremia in patients with hematological malignancies . Analysis of risk factors, etiological agents and prognostic indicators; Pagano L et al.; BACKGROUND AND OBJECTIVE: Patients with hematological malignancies are at increased risk for developing bacteremia . No previous study has investigated the risk and prognostic indicators of bacteremia in such patients using a statistical approach . METHODS: A case-control study was performed in 106 patients with hematological malignancies (group A) . Two hundred and twelve patients were included as controls and divided into two groups: 106 patients with hematological malignancy without bacteremia (group B) and 106 HIV-infected patients with bacteremia (group C) . RESULTS: At univariate analysis, bacteremia risk factors in group A were: neutropenia for more than six days (p = 0.03 vs . group B), central venous catheter usage (p = 0.04) and absence of antibiotic prophylaxis (p = 0.03) . At multivariate analysis, the use of CVC and neutropenia were independent bacteremia risk factors . The most frequent etiological agents were: Staphylococcus epidermidis and Pseudomonas aeruginosa . Comparing groups A and C, the distribution of Staphylococcus spp . was different, with S . epidermidis being prevalent in hematological patients only . As regards gram-negative organisms, it is of note that no episode of NT-Salmonella bacteremia was observed in group A, unlike group C, where they represent the second leading etiological agents . In group A, 14% of the patients died . Persistent neutropenia (p = 0.01) and the presence of relapsed neoplasm (p = 0.04) were prognostic indicators of bacteremia . INTERPRETATION AND CONCLUSIONS: Our findings suggest that bacteremia in patients with hematological malignancies strictly correlates with the intensity and length of neutropenia and CVC usage . Although we observed a low mortality rate, we stress that this clinical condition requires special attention from the physician, who must recognize and treat it promptly. Pathol Biol (Paris), 1997 May, 45(5), 415 - 9 In vitro activity of cefixime versus ceftizoxime against Salmonella typhi; Rastegar Lari A et al.; Emergence of multi-resistant strains of Salmonella typhi is a major problem in treatment of typhoid fever and requires an excessive hospitalization period . Therefore, the present study was carried out to estimate the degree of the resistance of S . typhi strains to various antibiotics such as cefixime . Fifty two strains of Salmonella typhi isolated from patients with typhoid fever and their sensitivity to various antibiotics was determined . MICs of cefixime and chloramphenicol were also determined according to comitee de l'antibiogramme francais . Results indicated that 41.9%, 33.9%, 38.7%, 58.1% and 1.6% of isolated strains were resistant to chloramphenicol, co-trimoxazole, ampicillin, tetracycline and gentamycin respectively . About one third (33.9%) of strains showed multiple resistance to the first four mentioned antibiotics . All strains were susceptible to ceftizoxime and cefixime (MICs 1 and less than 1 mcg/ml) . It could be concluded that cefixime due to its effectiveness, oral administration and shorter courses of treatment could be the therapy of choice in cases of typhoid fever caused by multiple resistant strains especially when we have a shortage of hospital beds. Collegian, 1997 Jul, 4(3), 36 - 7 Salmonella: a villain in 'food poisoning'; Leaver M; The majority of these reports occurred during and shortly after the hottest summer recorded in Melbourne . It has been suggested that meat coming from the abattoirs may have carried a higher than usual load of organisms . Variability of the severity of the symptoms is related to host factors and food handling as well as to the virulence of the particular serovar . Investigations by the staff of the Department of Human Services revealed some major errors in food handling in some situations and minor breaches in others . Mishandling by consumers is also likely (Lester et al 1997) . Such outbreaks serve to remind us not only of the importance, particularly in hot weather, of careful handling of meat, especially smallgoods, but also of the need for rapid notification to the appropriate authority of diarrhoeal illness where food is suspected to be the cause. Trends Microbiol, 1997 Sep, 5(9), 343 - 9 How Salmonella became a pathogen; Groisman EA et al.; In many pathogens, virulence can be conferred by a single region of the genome . In contrast, the facultative intracellular lifestyle of Salmonella demands a large number of genes distributed around the chromosome . The evolution of Salmonella has been marked by the acquisition of several 'pathogenicity islands', each contributing to the unique virulence properties of this microorganism. Rev Inst Med Trop Sao Paulo, 1996 Sep-Oct, 38(5), 315 - 22 Changing patterns of Salmonella serovars: increase of Salmonella enteritidis in São Paulo, Brazil; Tavechio AT et al.; Serovars of a total of 5,490 Salmonella strains isolated during the period of 1991-95, from human infections (2,254 strains) and from non-human materials (3,236 strains) were evaluated . In the studied period, 81 different serovars were determined among human isolates . Salmonella Enteritidis corresponded to 1.2% in 1991, 2% in 1992, 10.1% in 1993, 43.3% in 1994, and 64.9% in 1995 of all isolates . A significant rise on the isolation of this serovar was seen since 1993 linked to food poisoning outbreaks . It is reported also an increase on the isolation of S . Enteritidis from blood cultures, associated mainly with patients with immunodeficiency syndrome . S . Enteritidis was prevalent among one hundred and thirty different serovars isolated from non-human sources . Increasing number of isolation of this serovar was seen from shell eggs, breeding flocks and from environmental samples . It is also reported a contamination of commercial feed stuffs by S . Enteritidis which represents a major concern for Brazilian poultry industry. Proc Natl Acad Sci U S A, 1997 Sep 2, 94(18), 9887 - 92 A secreted Salmonella protein with homology to an avirulence determinant of plant pathogenic bacteria; Hardt WD et al.; Bacterial pathogens have evolved sophisticated mechanisms to interact with their hosts . A specialized type III protein secretion system capable of translocating bacterial proteins into host cells has emerged as a central factor in the interaction between a variety of mammalian and plant pathogenic bacteria with their hosts . Here we describe AvrA, a novel target of the centisome 63 type III protein secretion system of Salmonella enterica . AvrA shares sequence similarity with YopJ of the animal pathogen Yersinia pseudotuberculosis and AvrRxv of the plant pathogen Xanthomonas campestris pv . vesicatoria . These proteins are the first examples of putative targets of type III secretion systems in animal and plant pathogenic bacteria that share sequence similarity . They may therefore constitute a novel family of effector proteins with related functions in the cross-talk of these pathogens with their hosts. J Bacteriol, 1997 Sep, 179(17), 5398 - 406 Mutational characterization of promoter regions recognized by the Salmonella dublin virulence plasmid regulatory protein SpvR; Grob P et al.; The virulence plasmid-encoded spv regulon is essential for virulence of Salmonella dublin in mice . The spvR gene product belongs to the LysR family of transcriptional regulator proteins . SpvR induces the expression of the spvABCD operon and positively regulates its own expression . DNase I protection analysis with purified SpvR fusion proteins identified SpvR binding sites within the spvA and spvR promoters (P . Grob and D . G . Guiney, J . Bacteriol . 178:1813-1820, 1996) . We have used PCR mutagenesis, combined with functional selection for reduced SpvR affinity, to define the DNA elements essential for SpvR binding . For the spvR promoter fragment, a screen for reduced expression was also applied . Sequence analysis of the resulting mutant fragments reveals that the base pair changes are clustered in distinct regions . Determination of the apparent dissociation constants of SpvR for the mutant promoters showed that the spvA LysR-type motif and the upstream palindromic sequences of both promoters play an important role in SpvR recognition. Poult Sci, 1997 Sep, 76(9), 1232 - 8 Preharvest sources of Salmonella colonization in turkey production; Hoover NJ et al.; An ecological survey was conducted from March, 1995 to February 1996 to determine sources of Salmonella colonization in two flocks of turkeys reared consecutively in a newly constructed facility . Sampling was conducted prior to placement of poults, at Day 0, and again at 2, 10, 14, and 18 wk . Samples were collected at comparable times for the second flock except that final sampling occurred at 22 wk instead of 18 wk . Poult box liners, birds, new litter, drinkers, and air were sampled . Feed was collected from each shipment upon arrival at the facility . Feeders, drinkers, and used litter were monitored to evaluate horizontal transmission . Conventional methods for isolation and serological screening were used to analyze samples for the presence or absence of Salmonella . Prior to placement of the first flock, litter, drinkers, and air samples were negative for the presence of Salmonella, whereas drinkers were positive prior to placement of the second flock . Following placement of poults, 51.1, 63.8, and 22.8% of all litter, drinker, and air samples, respectively, were positive . Salmonella was isolated from 13.6% of poult box liners, 25.0% of yolk sac samples, and 53.8% of ceca, excluding Day 0 . Salmonella was isolated from 14.8% of feed shipments and 39.1% of feeder contents . Frequency of Salmonella detection was higher P < 0.05) in Flock 1 than Flock 2 for cecal and air samples . Salmonella colonization of turkey flocks and the spread of Salmonella within the environment was extensive once initial contamination of the production house occurred . Drinkers, feeders, litter, and air were critical sources of