Instruct: Given a scientific claim, retrieve relevant documents that support or refute the claim.
Query: There is a relation between Erythromycin use and hypertrophic pyloric stenosis.
OBJECTIVE To assess the association between use of macrolide antibiotics in mothers and infants from pregnancy onset until 120 days after birth and infantile hypertrophic pyloric stenosis (IHPS). DESIGN Nationwide register based cohort study. SETTING Denmark, 1996-2011. PARTICIPANTS 999,378 liveborn singletons and linked individual level information on macrolide prescriptions (maternal use during pregnancy, n=30,091; maternal use after birth, n=21,557; use in infants, n=6591), surgery for IHPS, and potential confounders. MAIN OUTCOME MEASURES Surgery for IHPS by three categories of macrolide use: in mothers during pregnancy, in mothers after birth, and in infants after birth. RESULTS 880 infants developed IHPS (0.9 cases per 1000 births). Compared with infants with no use of macrolides, the adjusted rate ratio for IHPS in infants with use of macrolides during days 0 to 13 after birth was 29.8 (95% confidence interval 16.4 to 54.1) and during days 14 to 120 was 3.24 (1.20 to 8.74); the corresponding absolute risk differences were 24.4 (95% confidence interval 13.0 to 44.1) and 0.65 (0.06 to 2.21) cases per 1000 infants exposed to macrolides, respectively. The rate ratio for maternal use of macrolides for days 0 to 13 after birth was 3.49 (1.92 to 6.34) and for days 14 to 120 was 0.70 (0.26 to 1.90); the corresponding absolute risk differences were 2.15 (0.82 to 4.64) and -0.11 (-0.26 to 0.31). The rate ratios for maternal use of macrolides during pregnancy were 1.02 (0.65 to 1.59) for weeks 0 to 27 and 1.77 (0.95 to 3.31) for weeks 28 to birth; the corresponding absolute risk differences were 0.01 (-0.31 to 0.50) and 0.67 (-0.06 to 2.02). CONCLUSIONS Treatment of young infants with macrolide antibiotics was strongly associated with IHPS and should therefore only be administered if potential treatment benefits outweigh the risk. Maternal use of macrolides during the first two weeks after birth was also associated with an increased risk of IHPS. A possible association was also found with use during late pregnancy.
BACKGROUND & AIMS Helicobacter pylori is an important etiologic factor in the development of gastric cancer. The aim of this study was to analyze the role of H. pylori infections in the induction of mutagenic events in gastric epithelial cells. The effect of a high-salt diet as a genotoxic risk factor was also investigated. METHODS Big Blue transgenic male mice (C57Bl/6) were inoculated with H. pylori (strain SS1) or Helicobacter felis (strain CS1) for 6 and 12 months. The frequency and spectrum of mutations at the stomach level were assessed. Inflammatory host response and inducible nitric oxide synthase (iNOS) expression by reverse-transcription polymerase chain reaction and immunohistochemistry analysis were also performed. RESULTS After 6 months, the gastric mutant frequency was 4-fold and 1.7-fold higher in mice infected with H. pylori and H. felis, respectively, than in uninfected mice. It was associated with a high frequency of transversions (AT --> CG and GC --> TA) known to result from oxidative damages. The Helicobacter-infected mice exhibited severe gastritis and a high level of iNOS messenger RNA expression. Hyperplasia developed 12 months after inoculation, and both the mutagenic effects and iNOS expression decreased in H. pylori- and H. felis-infected mice. No synergistic effects of a high-salt diet and Helicobacter infection were observed regarding the frequency of gastric mutation. CONCLUSIONS A direct gastric mutagenic effect due to H. pylori infection in the Big Blue transgenic mouse model has been shown 6 months after inoculation. This genotoxicity can be attributable to oxidative DNA damage involving the inflammatory host response.
BACKGROUND & AIMS Chronic infection with the bacterial pathogen Helicobacter pylori causes gastric disorders, ranging from chronic gastritis to gastric adenocarcinoma. Only a subset of infected persons will develop overt disease; most remains asymptomatic despite lifelong colonization. This study aims to elucidate the differential susceptibility to H pylori that is found both across and within populations. METHODS We have established a C57BL/6 mouse model of H pylori infection with a strain that is capable of delivering the virulence factor cytotoxin-associated gene A (CagA) into host cells through the activity of a Cag-pathogenicity island-encoded type IV secretion system. RESULTS Mice infected at 5-6 weeks of age with CagA(+)H pylori rapidly develop gastritis, gastric atrophy, epithelial hyperplasia, and metaplasia in a type IV secretion system-dependent manner. In contrast, mice infected during the neonatal period with the same strain are protected from preneoplastic lesions. Their protection results from the development of H pylori-specific peripheral immunologic tolerance, which requires transforming growth factor-β signaling and is mediated by long-lived, inducible regulatory T cells, and which controls the local CD4(+) T-cell responses that trigger premalignant transformation. Tolerance to H pylori develops in the neonatal period because of a biased ratio of T-regulatory to T-effector cells and is favored by prolonged low-dose exposure to antigen. CONCLUSIONS Using a novel CagA(+)H pylori infection model, we report here that the development of tolerance to H pylori protects from gastric cancer precursor lesions. The age at initial infection may thus account for the differential susceptibility of infected persons to H pylori-associated disease manifestations.
CONTEXT Increasing evidence supports the hypothesis of a causal association between certain bacterial infections and increased risk of developing acute myocardial infarction. If such a causal association exists, subjects who used antibiotics active against the bacteria, regardless of indication, might be at lower risk of developing acute myocardial infarction than nonusers. OBJECTIVE To determine whether previous use of antibiotics decreases the risk of developing a first-time acute myocardial infarction. DESIGN Population-based case-control analysis. SETTING The United Kingdom-based General Practice Research Database comprising 350 general practices. PATIENTS A total of 3315 case patients aged 75 years or younger with a diagnosis of first-time acute myocardial infarction between 1992 and 1997 and 13139 controls without myocardial infarction matched to cases for age, sex, general practice attended, and calendar time. MAIN OUTCOME MEASURES Use of antibiotics among those who did or did not have a first-time acute myocardial infarction. RESULTS Cases were significantly less likely to have used tetracycline antibiotics (adjusted odds ratio [OR], 0.70; 95% confidence interval [CI], 0.55-0.90) or quinolones (adjusted OR, 0.45; 95% CI, 0.21-0.95). No effect was found for previous use of macrolides (primarily erythromycin), sulfonamides, penicillins, or cephalosporins. CONCLUSIONS The findings from this large case-control analysis provide further, albeit indirect, evidence for an association between bacterial infections with organisms susceptible to tetracycline or quinolone antibiotics and the risk of acute myocardial infarction. These results of preliminary nature should stimulate more research to further explore the role of infections in the etiology of acute myocardial infarction.
Epitope vaccine based on the enzyme urease of Helicobacter pylori is a promising option for prophylactic and therapeutic vaccination against H. pylori infection. In our previous study, the epitope vaccine CTB-UA, which was composed of the mucosal adjuvant cholera toxin B subunit (CTB) and an epitope (UreA183–203) from the H. pylori urease A subunit (UreA) was constructed. This particular vaccine was shown to have good immunogenicity and immunoreactivity and could induce specific neutralizing antibodies, which exhibited effectively inhibitory effects on the enzymatic activity of H. pylori urease. In this study, the prophylactic and therapeutic efficacy of the epitope vaccine CTB-UA was evaluated in a BALB/c mice model. The experimental results indicated that oral prophylactic or therapeutic immunization with CTB-UA significantly decreased H. pylori colonization compared with oral immunization with PBS. The results also revealed that the protection was correlated with antigen-specific IgG, IgA, and mucosal secretory IgA antibody responses. CTB-UA may be a promising vaccine candidate for the control of H. pylori infection.
BACKGROUND Crohn's disease (CD)-associated dysbiosis is characterised by a loss of Faecalibacterium prausnitzii, whose culture supernatant exerts an anti-inflammatory effect both in vitro and in vivo. However, the chemical nature of the anti-inflammatory compounds has not yet been determined. METHODS Peptidomic analysis using mass spectrometry was applied to F. prausnitzii supernatant. Anti-inflammatory effects of identified peptides were tested in vitro directly on intestinal epithelial cell lines and on cell lines transfected with a plasmid construction coding for the candidate protein encompassing these peptides. In vivo, the cDNA of the candidate protein was delivered to the gut by recombinant lactic acid bacteria to prevent dinitrobenzene sulfonic acid (DNBS)-colitis in mice. RESULTS The seven peptides, identified in the F. prausnitzii culture supernatants, derived from a single microbial anti-inflammatory molecule (MAM), a protein of 15 kDa, and comprising 53% of non-polar residues. This last feature prevented the direct characterisation of the putative anti-inflammatory activity of MAM-derived peptides. Transfection of MAM cDNA in epithelial cells led to a significant decrease in the activation of the nuclear factor (NF)-κB pathway with a dose-dependent effect. Finally, the use of a food-grade bacterium, Lactococcus lactis, delivering a plasmid encoding MAM was able to alleviate DNBS-induced colitis in mice. CONCLUSIONS A 15 kDa protein with anti-inflammatory properties is produced by F. prausnitzii, a commensal bacterium involved in CD pathogenesis. This protein is able to inhibit the NF-κB pathway in intestinal epithelial cells and to prevent colitis in an animal model.
Half the world's population is chronically infected with Helicobacter pylori, causing gastritis, gastric ulcers and an increased incidence of gastric adenocarcinoma. Its proton-gated inner-membrane urea channel, HpUreI, is essential for survival in the acidic environment of the stomach. The channel is closed at neutral pH and opens at acidic pH to allow the rapid access of urea to cytoplasmic urease. Urease produces NH(3) and CO(2), neutralizing entering protons and thus buffering the periplasm to a pH of roughly 6.1 even in gastric juice at a pH below 2.0. Here we report the structure of HpUreI, revealing six protomers assembled in a hexameric ring surrounding a central bilayer plug of ordered lipids. Each protomer encloses a channel formed by a twisted bundle of six transmembrane helices. The bundle defines a previously unobserved fold comprising a two-helix hairpin motif repeated three times around the central axis of the channel, without the inverted repeat of mammalian-type urea transporters. Both the channel and the protomer interface contain residues conserved in the AmiS/UreI superfamily, suggesting the preservation of channel architecture and oligomeric state in this superfamily. Predominantly aromatic or aliphatic side chains line the entire channel and define two consecutive constriction sites in the middle of the channel. Mutation of Trp 153 in the cytoplasmic constriction site to Ala or Phe decreases the selectivity for urea in comparison with thiourea, suggesting that solute interaction with Trp 153 contributes specificity. The previously unobserved hexameric channel structure described here provides a new model for the permeation of urea and other small amide solutes in prokaryotes and archaea.
Helicobacter pylori persistently colonizes humans, causing gastritis, ulcers, and gastric cancer. Adherence to the gastric epithelium has been shown to enhance inflammation, yet only a few H. pylori adhesins have been paired with targets in host tissue. The alpAB locus has been reported to encode adhesins involved in adherence to human gastric tissue. We report that abrogation of H. pylori AlpA and AlpB reduces binding of H. pylori to laminin while expression of plasmid-borne alpA or alpB confers laminin-binding ability to Escherichia coli. An H. pylori strain lacking only AlpB is also deficient in laminin binding. Thus, we conclude that both AlpA and AlpB contribute to H. pylori laminin binding. Contrary to expectations, the H. pylori SS1 mutant deficient in AlpA and AlpB causes more severe inflammation than the isogenic wild-type strain in gerbils. Identification of laminin as the target of AlpA and AlpB will facilitate future investigations of host-pathogen interactions occurring during H. pylori infection.
Helicobacter pylori infection causes gastric pathology such as ulcer and carcinoma. Because H. pylori is auxotrophic for cholesterol, we have explored the assimilation of cholesterol by H. pylori in infection. Here we show that H. pylori follows a cholesterol gradient and extracts the lipid from plasma membranes of epithelial cells for subsequent glucosylation. Excessive cholesterol promotes phagocytosis of H. pylori by antigen-presenting cells, such as macrophages and dendritic cells, and enhances antigen-specific T cell responses. A cholesterol-rich diet during bacterial challenge leads to T cell–dependent reduction of the H. pylori burden in the stomach. Intrinsic α-glucosylation of cholesterol abrogates phagocytosis of H. pylori and subsequent T cell activation. We identify the gene hp0421 as encoding the enzyme cholesterol-α-glucosyltransferase responsible for cholesterol glucosylation. Generation of knockout mutants lacking hp0421 corroborates the importance of cholesteryl glucosides for escaping phagocytosis, T cell activation and bacterial clearance in vivo. Thus, we propose a mechanism regulating the host–pathogen interaction whereby glucosylation of a lipid tips the scales towards immune evasion or response.
CONTEXT Peristomal pyoderma gangrenosum (PPG), an unusual variant of pyoderma gangrenosum, has been reported almost exclusively in patients with inflammatory bowel disease (IBD) and is frequently misdiagnosed. OBJECTIVE To better characterize the clinical manifestations, diagnosis, and management of PPG. DESIGN, SETTING, AND PATIENTS Retrospective analysis of 7 patients with PPG observed in a university-affiliated community setting between 1988 and December 1999. MAIN OUTCOME MEASURES Clinical and histopathologic features, associated disorders, and microbiologic findings. RESULTS Two patients had Crohn disease, 2 had ulcerative colitis, and 3 had abdominal cancer. Five patients had at least 1 relapse of PPG after initial healing. Although 3 of 4 patients with IBD had active bowel disease, a parallel course with PPG occurred in only 1 patient. Both patients whose stoma was relocated developed an ulcer at the new site. Effective therapies included topical superpotent corticosteroids; intralesional injection of triamcinolone acetonide at the ulcer margin; topical cromolyn sodium; oral dapsone, prednisone, cyclosporine, mycophenolate mofetil; and intravenous infliximab. CONCLUSION Our experiences demonstrate that although PPG has been most often reported in patients with IBD, it may occur in the absence of IBD. Biopsy of the skin lesion is not diagnostic but excludes other causes. Relocation of the stoma may be associated with a new ulceration and should be avoided. Trauma to the skin of a predisposed patient may elicit the pustules or ulcerations associated with pathergy. JAMA. 2000;284:1546-1548.
Infection with Helicobacter pylori (H. pylori) is a risk factor for the development of gastric cancer. Here we show that infection of gastric epithelial cells with 'cag' pathogenicity island (cagPAI)-positive H. pylori induced aberrant expression of activation-induced cytidine deaminase (AID), a member of the cytidine-deaminase family that acts as a DNA- and RNA-editing enzyme, via the IκB kinase–dependent nuclear factor-κB activation pathway. H. pylori–mediated upregulation of AID resulted in the accumulation of nucleotide alterations in the TP53 tumor suppressor gene in gastric cells in vitro. Our findings provide evidence that aberrant AID expression caused by H. pylori infection might be a mechanism of mutation accumulation in the gastric mucosa during H. pylori–associated gastric carcinogenesis.
BACKGROUND & AIMS Helicobacter pylori-induced gastric epithelial cell (GEC) apoptosis is a complex process that includes activation of the tumor suppressor p53. p53-mediated apoptosis involves p53 activation, bax transcription, and cytochrome c release from mitochondria. Apurinic/apyrimidinic endonuclease-1 (APE-1) regulates transcriptional activity of p53, and H pylori induce APE-1 expression in human GECs. H pylori infection increases intracellular calcium ion concentration [Ca2+]i of GECs, which induces APE-1 acetylation. We investigated the effects of H pylori infection and APE-1 acetylation on GEC apoptosis. METHODS AGS cells (wild-type or with suppressed APE-1), KATO III cells, and cells isolated from gastric biopsy specimens were infected with H pylori. Effects were examined by immunoblotting, real-time reverse-transcription polymerase chain reaction, immunoprecipitation, immunofluorescence microscopy, chromatin immunoprecipitation, mobility shift, DNA binding, and luciferase assays. RESULTS H pylori infection increased [Ca2+]i and acetylation of APE-1 in GECs, but the acetylation status of APE-1 did not affect the transcriptional activity of p53. In GECs, expression of a form of APE-1 that could not be acetylated increased total and mitochondrial levels of Bax and induced release of cytochrome c and fragmentation of DNA; expression of wild-type APE-1 reduced these apoptotic events. We identified a negative calcium response element in the human bax promoter and found that poly (adenosine diphosphate-ribose) polymerase 1 recruited the acetylated APE-1/histone deacetylase-1 repressor complex to bax nCaRE. CONCLUSIONS H pylori-mediated acetylation of APE-1 suppresses Bax expression; this prevents p53-mediated apoptosis when H pylori infect GECs.
Postoperative vomiting (POV) remains one of the commonest causes of significant morbidity after tonsillectomy in children. A variety of prophylactic anti-emetic interventions have been reported, but there has only been a limited systematic review in this patient group. A systematic search was performed by using Cochrane Controlled Trials Register, MEDLINE and EMBASE to identify double-blind, randomized, placebo-controlled trials of prophylactic anti-emetic interventions in children undergoing tonsillectomy, with or without adenoidectomy. The outcome of interest was POV in the first 24 h. Summary estimates of the effect of each prophylactic anti-emetic strategy were derived using fixed effect meta-analysis. Where appropriate, dose-response effects were estimated using logistic regression and 22 articles were identified. Good evidence was found for the prophylactic anti-emetic effect of dexamethasone [odds ratio (OR) 0.23, 95% CI 0.16-0.33], and the serotinergic antagonists ondansetron (OR 0.36, 95% CI 0.29-0.46), granisetron (OR 0.11, 95% CI 0.06-0.19), tropisetron (OR 0.15, 95% CI 0.06-0.35) and dolasetron (OR 0.25, 95% CI 0.1-0.59). Metoclopramide was also found to be efficacious (OR 0.51, 95% CI 0.34-0.77). There is not sufficient evidence to suggest that dimenhydrinate, perphenazine or droperidol, in the doses studied, are efficacious, nor were gastric aspiration or acupuncture. In conclusion, dexamethasone and the anti-serotinergic agents appear to be the most effective agents for the prophylaxis for POV in children undergoing tonsillectomy.
BACKGROUND & AIMS Although the p53 tumor suppressor has been extensively studied, many critical questions remain unanswered about the biological functions of p53 homologs, p73 and p63. Accumulating evidence suggests that both p73 and p63 play important roles in regulation of apoptosis, cell differentiation, and therapeutic drug sensitivity. METHODS Gastric epithelial cells were cocultured with Helicobacter pylori, and the roles of p63 and p73 proteins were assessed by luciferase reporter, real-time polymerase chain reaction, immunoblotting, and cell survival assays. Short hairpin RNA and dominant-negative mutants were used to inhibit activity of p73 and p63 isoforms. Human and murine gastric tissues were analyzed by immunohistochemistry with p73 and p63 antibodies and modified Steiner's silver method. RESULTS Interaction of H pylori with gastric epithelial cells leads to robust up-regulation of p73 protein in vitro and in vivo in human gastritis specimens and H pylori-infected mice. The p73 increase resulted in up-regulation of pro-apoptotic genes, NOXA, PUMA, and FAS receptor in gastric epithelial cells. Down-regulation of p73 activity suppressed cell death and Fas receptor induced by H pylori. Bacterial virulence factors within the cag pathogenicity island, c-Abl tyrosine kinase, and interaction with p63 isoforms control the activity of p73. CONCLUSION Our findings implicate p73 in H pylori-induced apoptosis and more generally suggest that the p53 family may play a role in the epithelial cell response to H pylori infection.
In recent years infection caused by Salmonella serotype Enteritidis (SE) phage type 4 has spread through Europe but has been uncommon in the USA. The first recognized outbreak of this strain in the USA occurred in a Chinese restaurant in EI Paso, Texas, in April 1993; no source was identified. In September 1993, a second outbreak caused by SE phage type 4 was associated with the same restaurant. To determine the cause of the second outbreak, we compared food exposures of the 19 patients with that of two control groups. Egg rolls were the only item significantly associated with illness in both analyses (first control group: odds ratio [OR] 8.2, 95% confidence interval [CI] 2.3-31.6; second control group: OR 13.1, 95% CI 2.1-97.0). Retrospective analysis of the April outbreak also implicated egg rolls (OR 32.4, 95% CI 9.1-126.6). Egg roll batter was made from pooled shell eggs and was left at room temperature throughout the day. These two outbreaks of SE phage type 4 likely could have been prevented by using pasteurized eggs and safe food preparation practices.
Carriage of Helicobacter pylori strains producing more active (s1/i1) forms of VacA is strongly associated with gastric adenocarcinoma. To our knowledge, we are the first to determine effects of different polymorphic forms of VacA on inflammation and metaplasia in the mouse stomach. Bacteria producing the less active s2/i2 form of VacA colonized mice more efficiently than mutants null for VacA or producing more active forms of it, providing the first evidence of a positive role for the minimally active s2/i2 toxin. Strains producing more active toxin forms induced more severe and extensive metaplasia and inflammation in the mouse stomach than strains producing weakly active (s2/i2) toxin. We also examined the association in humans, controlling for cagPAI status. In human gastric biopsy specimens, the vacA i1 allele was strongly associated with precancerous intestinal metaplasia, with almost complete absence of intestinal metaplasia in subjects infected with i2-type strains, even in a vacA s1, cagA(+) background.
Methanosphaera stadtmaniae is a non-motile, Gram-positive spherical-shaped organism that obtains energy for growth by using hydrogen to reduce methanol to methane. It does not produce methane from hydrogen and carbon dioxide, formate, acetate or methylamines and cannot grow with hydrogen and carbon monoxide, nitrate, fumarate, sulfate or choline. Its pH optimum is 6.5 to 6.9 and its temperature optimum is 36° to 40° C. It is not inhibited by bile salts, inhibitors of the synthesis of folic acid coenzymes, cephalothin or clindamycin but is inhibited by metronidazole, bacitracin, monensin, lasalocid, or bromoethanesulfonate. It requires acetate, carbon dioxide, isoleucine, ammonium, and thiamin for growth and biotin is stimulatory. It does not contain cytochromes and the mol % G+C of its DNA is 25.8. The composition of its cell wall and 16 S rRNA and its immunological fingerprint are consistent with characterization of the organism as a member of a new genus of the family Methanobacteriaceae. The habitat of the type strain is the human large intestine.
The gut mucosal epithelium separates the host from the microbiota, but enteropathogens such as Salmonella Typhimurium (S.Tm) can invade and breach this barrier. Defenses against such acute insults remain incompletely understood. Using a murine model of Salmonella enterocolitis, we analyzed mechanisms limiting pathogen loads in the epithelium during early infection. Although the epithelium-invading S.Tm replicate initially, this intraepithelial replicative niche is restricted by expulsion of infected enterocytes into the lumen. This mechanism is compromised if inflammasome components (NAIP1-6, NLRC4, caspase-1/-11) are deleted, or ablated specifically in the epithelium, resulting in ∼100-fold higher intraepithelial loads and accelerated lymph node colonization. Interestingly, the cytokines downstream of inflammasome activation, interleukin (IL)-1α/β and IL-18, appear dispensable for epithelial restriction of early infection. These data establish the role of an epithelium-intrinsic inflammasome, which drives expulsion of infected cells to restrict the pathogen's intraepithelial proliferation. This may represent a general defense mechanism against mucosal infections.
The hygiene hypothesis is thought to be a significant contributor to the growing incidence of inflammatory bowel disease (IBD) around the world, although the evidence for specific factors that underlie the hygiene hypothesis in IBD is unclear. We aimed to systematically review the literature to determine which hygiene-related factors are associated with the development of IBD. Publications identified from a broad based MEDLINE and Current Contents search between 1966 and 2007 on key terms relevant to the 'hygiene hypothesis' and IBD including H pylori exposure, helminths, cold chain hypothesis, measles infection and vaccination, antibiotic use, breastfeeding, family size, sibship, urban upbringing, day care attendance and domestic hygiene were reviewed. The literature suggests that the hygiene hypothesis and its association with decreased microbial exposure in childhood probably plays an important role in the development of IBD, although the strength of the supporting data for each of the factors varies considerably. The most promising factors that may potentially be associated with development of IBD include H pylori exposure, helminths, breastfeeding and sibship. However, the vast majority of studies in this area are plagued by serious methodological shortcomings, particularly the reliance on retrospective recall of information making it difficult to truly ascertain the importance of a 'hygiene hypothesis' in IBD. The 'hygiene hypothesis' in IBD is an important area of research that may give clues to the aetiology of this disease. Directions for future research are recommended.
BACKGROUND & AIMS Various commensal enteric and potentially pathogenic bacteria may be involved in the pathogenesis of inflammatory bowel diseases (IBD). We compared the risk of IBD between a cohort of patients with documented Salmonella or Campylobacter gastroenteritis and an age- and gender-matched control group from the same population in Denmark. METHODS We identified 13,324 patients with Salmonella/Campylobacter gastroenteritis from laboratory registries in North Jutland and Aarhus counties, Denmark, from 1991 through 2003, and 26,648 unexposed controls from the same counties. Of these, 176 exposed patients with IBD before the infection, their 352 unexposed controls, and 80 unexposed individuals with IBD before the Salmonella/Campylobacter infection were excluded. The final study cohort of 13,148 exposed and 26,216 unexposed individuals were followed for up to 15 years (mean, 7.5 years). RESULTS A first-time diagnosis of IBD was reported in 107 exposed (1.2%) and 73 unexposed individuals (0.5%). By age, gender, and comorbidity adjusted Cox proportional hazards regression analysis, the hazard ratio (95% confidence interval) for IBD was 2.9 (2.2-3.9) for the whole period and 1.9 (1.4-2.6) if the first year after the Salmonella/Campylobacter infection was excluded. The increased risk in exposed subjects was observed throughout the 15-year observation period. The increased risk was similar for Salmonella (n = 6463) and Campylobacter (n = 6685) and for a first-time diagnosis of Crohn's disease (n = 47) and ulcerative colitis (n = 133). CONCLUSIONS In our population-based cohort study with complete follow-up, an increased risk of IBD was demonstrated in individuals notified in laboratory registries with an episode of Salmonella/Campylobacter gastroenteritis.
PriB is a primosomal protein required for re-initiation of replication in bacteria. We characterized and compared the DNA-binding properties of PriB from Salmonella enterica serovar Typhimurium LT2 (StPriB) and Escherichia coli (EcPriB). Only one residue of EcPriB, V6, was different in StPriB (replaced by A6). Previous structural information revealed that this residue is located on the putative dimer-dimer interface of PriB and is not involved in single-stranded DNA (ssDNA) binding. The cooperative binding mechanism of StPriB to DNA is, however, very different from that of EcPriB. Unlike EcPriB, which forms a single complex with ssDNAs of various lengths, StPriB forms two or more distinct complexes. Based on these results, as well as information on structure, binding modes for forming a stable complex of PriB with ssDNA of 25 nucleotides (nt), (EcPriB)25, and (StPriB)25 are proposed.
Objective:A number of case reports describe multiple family members with gastroesophageal reflux disease and Barrett's esophagus. The wider importance of familial factors in gastroesophageal reflux disease has not been established. Therefore, we have studied the prevalence of reflux symptoms and medication use among relatives of patients with documented gastroesophageal reflux disease. Methods:A postal questionnaire study of the first degree relatives of six groups of matched patients. The groups comprised patients with 1) no dyspeptic symptoms; 2) reflux symptoms and a normal pH study; 3) reflux symptoms, an abnormal pH study, and a lower esophageal sphincter (LOS) pressure more than 10 mm Hg; 4) reflux symptoms, an abnormal pH study, and a LOS pressure less than 10 mm Hg; 5) Barrett's esophagus; and 6) peptic stricture. Results:Four hundred eighteen subjects replied (78% response). Infrequent reflux symptoms were equally common in all groups of relatives. Frequent reflux symptoms, however, were more common among relatives of patients with an abnormal pH study and normal (26%, p= 0.007) or low LOS pressure (27%, p= 0.01) or Barrett's esophagus (30%, p= 0.003), compared with relatives of nondyspeptic patients (9%). Frequent reflux symptoms were no more common among relatives of patients with a normal pH study (16%) or peptic stricture (18%). Reflux medication use showed a similar pattern. Conclusions:Familial clustering of reflux symptoms is seen in relatives of patients with reflux symptoms and increased esophageal acid exposure and in relatives of patients with Barrett's esophagus.
OBJECTIVE The effects of hydroxyethyl starch on bleeding after cardiopulmonary bypass were determined. METHODS A meta-analysis was performed of postoperative blood loss in randomized clinical trials of hydroxyethyl starch versus albumin for fluid management in adult cardiopulmonary bypass surgery. Impacts of hydroxyethyl starch molecular weight and molar substitution were assessed. Randomized trials directly comparing different hydroxyethyl starch solutions were also included. RESULTS Eighteen trials with 970 total patients were included. Compared with albumin, hydroxyethyl starch increased postoperative blood loss by 33.3% of a pooled SD (95% confidence interval, 18.2%-48.3%; P < .001). Risk of reoperation for bleeding was more than doubled by hydroxyethyl starch (relative risk, 2.24; 95% confidence interval, 1.14-4.40; P = .020). Hydroxyethyl starch increased transfusion of red blood cells by 28.4% of a pooled SD (95% confidence interval, 12.2%-44.6%; P < .001), of fresh-frozen plasma by 30.6% (95% confidence interval, 8.0%-53.1%; P = .008), and of platelets by 29.8% (95% confidence interval, 3.4%-56.2%; P = .027). None of these effects differed significantly between hydroxyethyl starch 450/0.7 and 200/0.5. Insufficient data were available for hydroxyethyl starch 130/0.4 versus albumin; however, no significant differences were detected in head-to-head comparisons of hydroxyethyl starch 130/0.4 with 200/0.5. Albumin improved hemodynamics. There were no differences in fluid balance, ventilator time, intensive care unit stay, or mortality. CONCLUSIONS Hydroxyethyl starch increased blood loss, reoperation for bleeding, and blood product transfusion after cardiopulmonary bypass. There was no evidence that these risks could be mitigated by lower molecular weight and substitution.
Helicobacter pylori induces motogenic and cytoskeletal responses in gastric epithelial cells. We demonstrate that these responses can be induced via independent signaling pathways that often occur in parallel. The cag pathogenicity island appears to be nonessential for induction of motility, whereas the elongation phenotype depends on translocation and phosphorylation of CagA.
We report a case of postvaccination acute myopericarditis in an adolescent. The patient presented with acute chest pain, diffuse ST-segment elevation, and elevated cardiac enzyme levels. Cardiac MRI was consistent with acute myocarditis. He recovered within a few days with nonsteroidal antiinflammatory treatment and remains clinically stable, with improvement of MRI findings at the 10-week follow-up. Postvaccination cases of myopericarditis reported in the pediatric literature are also reviewed.