Characterization and multilocus sequence typing of Clostridium perfringens isolated from patients with diarrhoea and food poisoning in Tai'an region, China.

OBJECTIVES: Clostridium perfringens (C. perfringens) is a significant opportunistic pathogen. This study aims to examine the occurrence of C. perfringens in patients with diarrhoea and food poisoning and compare the genetic similarities with strains found in poultry retail markets and poultry farms in the same city (Tai'an, China). METHODS: Clostridium perfringens was isolated from 30 human faecal samples and genotyped using multiplex PCR. The antimicrobial susceptibility test was conducted using the Kirby-Bauer disk diffusion method. Genetic relationships were analysed through Multi-locus sequence typing (MLST) and Phylogenetic analysis. RESULTS: The positive rate of C. perfringens was found to be 96.67%. Among the positive samples, 91.67% of the faecal samples from patients with food poisoning contained type F strains of C. perfringens, while only 16.67% of the samples from diarrhoea cases contained type F. The drug susceptibility test revealed that the majority of isolates displayed broad-spectrum antimicrobial resistance. Out of the 57 isolates tested for drug susceptibility, 89.47% demonstrated resistance to at least three antibiotics. The MLST results indicated that strains originating from the same host and environment tended to be more closely related. However, certain strains associated with food poisoning and diarrhoea in patients shared the same ST and CC as some strains found in the retail market. These strains were also found to be phylogenetically similar to some retail market strains, suggesting potential risks to human health. CONCLUSIONS: Therefore, it is crucial to enhance the management of poultry retail markets in order to mitigate these associated risks.

The secondary bile acid, deoxycholate accelerates intestinal adenoma-adenocarcinoma sequence in Apc (min/+) mice through enhancing Wnt signaling.

Colorectal cancer is one of the leading causes of cancer deaths. It correlates to a high fat diet, which causes an increase of the secondary bile acids including deoxycholate (DOC) in the intestine. We aimed to determine the effects of DOC on intestinal carcinogenesis in Apc (min/+) mice, a model of spontaneous intestinal adenomas. Four-week old Apc (min/+) mice were treated with 0.2 % DOC in drinking water for 12 weeks. The number and size of tumors were measured, and tissue sections were prepared for the evaluation of intestinal carcinogenesis, cell proliferation, and apoptosis. The activation of Wnt signaling was detected in the intestinal tumor cells of the Apc (min/+) mice, and also in the human colon samples. DOC increased the number of intestine tumors by 165.1 % compared with that in untreated Apc (min/+) mice mainly in the middle and distal segments of the small intestine and colon. The numbers of all sizes of tumors in the small intestine were increased. Intestinal carcinogenesis was confirmed in 75 % mice in DOC treated-Apc (min/+) mice compared with 0 % in untreated mice. This was accompanied by promoting tumor cell proliferation and decreasing apoptosis, and increasing the percentage of ß-catenin positive cells and its nuclear expression in intestinal tumor cells of Apc (min/+) mice, and also up-regulating the expression of cyclin D1. In addition, the activation of Wnt signaling also played in modulating human colon carcinogenesis. Our studies suggest that DOC enhances the multiplicity of intestinal tumor, and accelerates intestinal adenoma-adenocarcinoma sequence in Apc (min/+) mice mediated by stimulating tumor cell proliferation and decreasing apoptosis through enhancing Wnt signaling.

Sporadic fundic gland polyps are not associated with proton pump inhibitors therapy but negatively correlate with Helicobacter pylori infection in China.

BACKGROUND: Sporadic fundic gland polyps (FGPs) are common gastric polyps. Some studies reported that FGPs dramatically increased due to proton pump inhibitors (PPIs) use and a decreased prevalence of Helicobacter pylori (H. pylori) infection in Western countries. However, data are still controversial. This study aimed to identify the relationships between these two factors and FGPs in China. METHODS: Consecutive patients with FGPs detected were retrospectively analyzed. Data including patients' age, sex, symptoms, H. pylori infection, history of PPIs use, and the polyps were documented. Each patient was compared with two randomly selected age- and sex-matched controls with similar symptoms in the same period. RESULTS: During the period from March 2011 to March 2012, a total of 328 patients were diagnosed as FGPs in 23 047 patients who underwent routine esophagogastroduodenoscopy and 656 patients without FGPs as controls. The mean age was (55.12±12.61) years, and 75.91% were women. The prevalence of H. pylori in patients with FGPs was significantly lower than in those without FGPs (22.30% (64/287) vs. 42.26% (224/530), P < 0.001, OR 0.392, 95% CI 0.283-0.544). Overall, a total of 54 patients with FGPs (54/328, 16.46%) and 136 patients without FGPs (136/656, 20.73%) received PPIs therapy (P = 0.110). According to the different duration of PPIs use, no significant differences of PPIs use were found between the cases and controls among all subgroups. Moreover, the PPIs use was also similar, regardless of age, sex, H. pylori infection, and the number of polyps. CONCLUSION: Sporadic FGPs may not be induced by PPIs therapy but negatively correlate with H. pylori infection in China, which is not the same with the data in Western countries.