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Background and aims:The relationship between Helicobacter pylori infection and gastro-oesophageal reflux disease (GORD) is controversial but it is accepted that GORD is associated with increased exposure to gastric acidity. The proinflammatory interleukin (IL)-1B polymorphisms increase the risk of hypochlorhydria and gastric atrophy. We examined the association between proinflammatory cytokine gene polymorphisms, presence of gastric atrophy, and risk of GORD in H pylori positive and negative subjects in Japan. Methods: We studied 320 consecutive dyspeptic patients without peptic ulcers or cancers. GORD symptoms were scored using the Carlsson-Dent questionnaire and erosive oesophagitis was assessed endoscopically. H pylori infection was diagnosed by urea breath test, histological examination, and serology. Gastric atrophy was assessed histologically, and polymorphisms in the IL-1B, IL-10, and tumour necrosis factor a (TNF-A) genes were genotyped. Results: Two hundred and eight patients were H pylori positive and 112 were negative. One hundred and eight (34%) were found to have erosive oesophagitis by endoscopic criteria (grade A: 78; grade B: 23; grade C: 6; grade D: 1). Erosive oesophagitis and GORD symptoms were significantly more common in H pylori negative compared with H pylori positive subjects (p,0.05). H pylori positive subjects were more likely to have corpus gastric atrophy than H pylori negative subjects (p,0.001). Among H pylori positive patients, those without erosive oesophagitis or GORD symptoms were significantly more likely to have corpus atrophy than subjects with erosive oesophagitis or GORD symptoms (p,0.05). Among H pylori positive patients, subjects homozygous for the proinflammatory allele IL-1B2511T had a significantly lower risk of erosive oesophagitis (odds ratio (OR) 0.06 (95% confidence interval (CI) 0.006-0.51); p = 0.01) and GORD symptoms (OR 0.10 (95% CI 0.01-0.85); p = 0.04) compared with those homozygous for the 2511C allele, while none of the two other proinflammatory cytokine gene polymorphisms had significant correlations with erosive oesophagitis or GORD symptoms. Conclusions: A proinflammatory IL-1B genotype is associated with increased risk of atrophy and decreased risk of GORD in H pylori infected subjects in Japan. These data indicate that in some genetically predisposed subjects, H pylori infection may protect against GORD through induction of gastric atrophy.

We investigated culture supernatant proteins from the M1 serotype of Streptococcus pyogenes by two-dimensional gel electrophoresis and peptide mass mapping analysis, and characterized the single protein spots. Among them, we analysed the Spy0747 protein. This protein is homologous to the SsnA protein, a cell-wall-located DNase expressed in Streptococcus suis serotype 2. We designated the Spy0747 protein as SpnA. SpnA protein was also detected in the insoluble fraction of whole-cell lysates using shotgun proteomic analysis, suggesting that SpnA is also located in the cell wall. SpnA was expressed as a glutathione S-transferase-fusion protein in Escherichia coli. We confirmed that the recombinant protein had DNase activity that was dependent on Ca 2+ and Mg 2+ , like SsnA. Blood bactericidal assays and mouse infection model experiments showed that the spnA knockout strain was less virulent than the parental strain, thus suggesting that SpnA could play an important role in virulence. Using PCR, we found that the spnA gene was present in all clinical S. pyogenes strains we examined. Our results, together with a previous report identifying Spy0747 as a surface-associated protein, suggest that SpnA is an important cell-wall-located DNase that is generally produced in S. pyogenes and is involved in virulence. INTRODUCTIONStreptococcus pyogenes is a Gram-positive bacterium infecting the upper respiratory tract, such as the tonsils and pharynx, and it also causes post-infection diseases such as rheumatic fever and glomerulonephritis. Furthermore, S. pyogenes causes many serious human diseases such as streptococcal toxic shock syndrome (STSS) (Cone et al., 1987;Cunningham, 2000). Because of the worldwide prevalence of STSS, a number of studies have been undertaken to identify relevant virulence factors (Hauser et al., 1991;Reichardt et al., 1992). These factors include M protein, streptococcal inhibitor of complement, streptococcal pyrogenic toxins, haemolysins, and several DNases (Cunningham, 2000). DNases have been extensively characterized (McCarty, 1949;Miyakawa et al., 1985;Ferreira et al., 1992). However, there was no direct evidence that DNases are virulence factors, until Sumby et al. (2005a) provided such evidence.We have investigated streptococcal exoproteins using 2-dimensional gel electrophoresis (2-DE) (Tanaka et al., 2005;Sawai et al., 2007). We have so far detected several DNases (Hasegawa et al., 2002a, b) and have analysed the influence of various culture conditions on production of these exoproteins (Nakamura et al., 2004). In these comprehensive analyses of culture supernatant proteins, we detected another putative DNase protein, Spy0747, in the culture supernatant of S. pyogenes SF370. The Spy0747 protein is homologous to the SsnA protein, which is a cell-wall-located DNase expressed in Streptococcus suis serotype 2 that requires Ca 2+ and Mg 2+ for its activity (Fontaine et al., 2004). Hence we designated the Spy0747 protein as SpnA. In the present study, we further characterized the SpnA protein an...

infection in severe UC patients treated with CyA is associated with poor outcome. Further, ganciclovir is useful for treatment of CMV-associated UC after immunosuppressive therapy. INTRODUCTIONCytomegalovirus (CMV) infection is one of the most common infectious complications after immunosuppressive therapy. It occurs mainly as a secondary infection in CMV-seropositive patients. CMV infection is a common viral infection in humans, occurring in 40%-100% of adults [1] . CMV infections are generally asymptomatic or are manifested as a mild mononucleosislike syndrome [2] . Significant CMV disease may occur in various organs such as the retina, lung, and gastrointestinal tract, and the target organ is related to the etiology of immunosuppression [1] . Gastrointestinal (GI) CMV infection is rare in immunocompetent individuals. Clinically significant GI CMV infection generally occurs in immuneocompromised patients [3] . In the gastrointestinal tract, CMV disease can occur in all locations, from the mouth to the rectum, and generally involves the formation of ulcers in the mucosa, often accompanied by hemorrhage [1] . Ulcerative colitis (UC) is common all over the world and is generally more frequent than Crohn's disease (CD) [4] . UC is thought to result from the inappropriate and progressive activation of the mucosal immune system driven by the presence of normal luminal flora. The aberrant response is most likely facilitated by defects in both the barrier function of the intestinal epithelium and the mucosal immune system [4] .

Streptococcal toxic shock syndrome (STSS) is a re-emerging infectious disease in Japan and many other developed countries. Epidemiological studies have revealed that the M1 serotype of Streptococcus pyogenes is the most dominant causative isolate of STSS. Recent characterization of M1 isolates revealed that the mutation of covS, one of the two-component regulatory systems, plays an important role in STSS by altering protein expression. We analyzed the M1 S. pyogenes clinical isolates before or after 1990 in Japan, using two-dimensional gel electrophoresis (2-DE) and pulsed-field gel electrophoresis (PFGE). PFGE profiles were different between the isolates before and after 1990. Markedly different profiles among isolates after 1990 from STSS and pharyngitis patients were detected. Sequence analysis of two-component regulatory systems showed that covS mutations were detected not only in STSS but also in three pharyngitis isolates, in which proteins from the culture supernatant displayed the invasive type. The mutated CovS detected in the pharyngitis isolates had impaired function on the production of streptococcal pyrogenic exotoxin B (SpeB) analyzed by 2-DE. These results suggest that several covS mutations that lead to the malfunction of the CovS protein occurred even in pharyngeal infection.

H. pylori-infected ITP patients have a corpus-predominant pattern of gastritis but the virulence profile of their strains does not differ from that of ulcer or NUD patients. Eradication of H. pylori infection is a good therapeutic option for some patients with chronic ITP, especially for those who develop ITP in older age.

Glycine is the simplest amino acid and is used as a metabolic product in some bacteria. However, an excess of glycine inhibits the growth of many bacteria, and it is used as a nonspecific antiseptic agent due to its low level of toxicity in animals. The effect of glycine on Helicobacter pylori is not precisely known. The present study was conducted to investigate (i) the effect of glycine on clarithromycin (CLR)-resistant and -susceptible strains of H. pylori, (ii) the effect of glycine in combination with amoxicillin (AMX), and (iii) the postantibiotic effect (PAE). The MIC at which 90% of strains are inhibited for glycine was almost 2.5 mg/ml for 31 strains of H. pylori, including CLR-resistant strains. We constructed isogenic CLR-resistant mutant strains by natural transformation and investigated the difference between clinical wild-type strains and isogenic mutants. There were no differences in the MICs between CLR-resistant and -susceptible strains or between clinical wild-type and mutant strains. The combination of AMX and glycine showed synergistic activity, with the minimum bactericidal concentration of AMX with glycine decreasing to 1/10 that of AMX alone. Glycine showed no PAE against H. pylori. These results suggest that glycine may be a useful antimicrobial agent against H. pylori not only alone but also in combination with antibacterial drugs for the treatment of H. pylori-associated diseases. Glycine may represent a component of a new type of eradication therapy for CLR-resistant H. pylori.

Gastric mucosal biopsy is widely used in the detection of Helicobacter pylori but is associated with a number of problems, including false-negative results due to sampling error and massive bleeding after biopsy. Given the extended period required to culture H. pylori, detection would be further improved by the use of rapid detection methods such as PCR. Here, we developed a rapid, safe, and convenient method for collecting H. pylori which combines endoscopic brushing with the loop-mediated isothermal amplification (LAMP) method. The specificity and sensitivity of LAMP were examined using nine urease-generating non-H. pylori bacterial species, Escherichia coli, Clostridium perfringens, Campylobacter jejuni, Helicobacter hepaticus, and 51 H. pylori strains. Results showed that H. pylori-specific LAMP primers amplified H. pylori DNA only and that the lowest detection limit of the LAMP reaction was 10 2 CFU. Brushing and biopsy samples taken from 200 patients with peptic ulcer at Nagoya University Hospital and a regional health care center were subjected to both LAMP and culturing. No adverse effects such as severe bleeding or penetration occurred during the procedure. By LAMP assay, 123 patients were confirmed as H. pylori positive when brushing technique samples were assayed, whereas only 100 were positive when biopsy samples were assayed. Culture assay detected H. pylori in 117 patients when it was combined with the brushing technique and in 96 when it was combined with biopsy. Combination of the endoscopic brushing technique with LAMP is considered a useful and safe system for identifying H. pylori infection.Helicobacter pylori infection is recognized as a major cause of peptic ulcer disease and gastric cancer (8,29). H. pylori occurs beneath the mucus layer, predominantly in the antrum (34). Infection is generally confirmed by histology (21), culturing (13), and the rapid urease test (RUT) (23) performed on endoscopic gastric mucosal biopsy samples or by the urea breath test (14). This latter test is a noninvasive method that detects 13 CO 2 generated by H. pylori urease (5); because it is indirect, however, it does not allow the measurement of antibiotic susceptibility, a disadvantage given that the recent gradual increase in the number of antibiotic-resistant strains has mandated susceptibility testing before eradication therapy (9, 25). The collection and identification of strains thus remain a valuable confirmation of infection and is necessary for the investigation of virulence (12, 25).Nevertheless, biopsy carries the risk of causing bleeding and cannot be used for patients with a bleeding tendency, resulting, for example, from liver cirrhosis or idiopathic thrombocytopenic purpura, notwithstanding the possible association of these diseases with H. pylori infection (11). A second problem is the existence of urease-generating bacteria other than H. pylori; a number of bacteria produce urease and may colonize the stomach in an acid suppression environment (24, 25), potentially confounding the differentiati...