Influence of Debaryomyces hansenii on bacterial lactase gene diversity in intestinal mucosa of mice with antibiotic-associated diarrhea.

AIM: The current study aimed to investigate the effects of Debaryomyces hansenii on the diversity of bacterial lactase gene in the intestinal mucosa of antibiotic-associated diarrhea (AAD) mice. METHODS: Eighteen mice were randomly divided into three groups (6 mice per group): healthy control group, diarrhea model group and D. hansenii treatment group. The antibiotic-associated diarrhea model was established by intragastric administration with a mixture of cephradine and gentamicin sulfate (23.33 mL·kg-1·d-1) twice a day for 5 days continuously. After establishing the AAD model, the mice in the D. hansenii treatment group were gavaged with D. hansenii for three days, while other groups were gavaged with distilled water. Then, the intestinal mucosa of all three groups was collected and DNA was extracted in an aseptic environment for the following analysis. RESULTS: The difference in the richness and homogeneity of the bacterial lactase gene among all samples were inapparent, as the difference in the Chao1, ACE, Simpson and Shannon indices among the three groups were insignificant (P>0.05). NMDS analysis also showed that the distance of the samples among the three groups was unobvious. Furthermore, the bacterial lactase gene in the mucosa mainly originated from Actinobacteria, Firmicutes and Proteobacteria. Compared with the healthy control group, the abundance of lactase genes originating from Cupriavidus, Lysobacter, Citrobacter, Enterobacter and Pseudomonas was increased in the D. hansenii treatment group, while the lactase gene from Acidovorax and Stenotrophomonas decreased (p < 0.01 or p < 0.05) in the diarrhea model group and the D. hansenii treatment group. CONCLUSION: D. hansenii was capable of improving the growth of some key lactase-producing bacteria like Deinococcus, Cupriavidus and Lysobacter for treating AAD.

Effects of Debaryomyces hansenii treatment on intestinal mucosa microecology in mice with antibiotic-associated diarrhea.

AIM: To confirm the effects of Debaryomyces hansenii on intestinal microecology in mice with antibiotic-associated diarrhea (AAD). METHODS: This study took the mucosal microecology as the entry point and an antibiotic mixture was used to induce diarrhea in mice. D. hansenii suspension was used to treat the mice and the bacterial communities of mucosa was analyzed using high-throughput sequencing. RESULTS: The Shannon-Wiener index indicated that the sequencing depth is reasonable and reflected the majority of microbial information. The principal coordinate analysis results showed that mice in the treatment group and the normal group had a similar microbial community structure, while differences in microbial community structure were observed between the model group and the treatment group. The inter-group bacterial structures were analyzed at the phylum level and genus level. The results revealed that antibiotic treatment increased the proportion of Proteobacteria and decreased the proportion of Bacteroides, while D. hansenii treatment inhibited the increase in Proteobacteria. Linear discriminant analysis coupled with effect size measurements (LEfSe) suggested d that the beneficial bacteria Candidatus Arthromitus were the only common bacteria in the normal group (P<0.05). CONCLUSION: The treatment with D.hansenii could contribute to the maintenance of the structure of the mucosal microbiota in comparison with the normal group and inhibit the proliferation of opportunistic bacteria. However, high-dose antibiotic treatment causes mucosal dysbiosis and the proliferation of opportunistic bacteria during the self-recovery period, such as Pseudoalteromonas, Alteromonas, Vibrio.

[Persistent type 2 lepra reaction (erythema nodosum) and clofazimine-induced lethal enteropathy]. / Eritema nudoso leproso persistente y enteropatía letal por clofazimina.

INTRODUCTION: Clofazimine enterophathy is a serious complication of clofazimine when used at high doses for treatment of type 2 lepra or or erythema nodosum leprosum. Objective. A woman is presented who had a delayed diagnosis of leprosy, persistent type 2 lepra reaction and lethal clofazimine enteropathy. MATERIALS AND METHODS: A 31-year-old woman presented leprosy symptoms over a 16-year period without medical diagnosis of her disease. During this period, type 2 lepra episodes occurred, but were not accurately diagnosed. These episodes became more severe during her second pregnancy. The patient and her family were interviewed, and her clinical history reviewed. RESULTS: After twelve years of medical consults, lepromatous leprosy was diagnosed, based on perforation of her nasal septum, with a bacterial index of 5. Her husband and a 12-year-old daughter have leprosy symptoms. During multidrug therapy, she presented with repeated type 2 lepra reaction episodes for which she received daily clofazimine 400 mg doses. Two months after this treatment, severe and frequent episodes of intense abdominal pain began to occur. These persisted for more than a year and were managed with in-hospital administration of several classes of painkillers and antispasmodic medication, including morphine. She also presented with sporadic diarrhea, constipation, nausea, weight loss and mesenteric adenopathies. She died finally due to this intestinal condition. No autopsy was performed. CONCLUSIONS: The patient's clinical presentation suggested a clofazimine-induced lethal enteropathy, a complication not previously seen in Colombia. This connection was not recognized by the medical officers that treated the patient.

Isolation of Prorocentrum lima (Syn. Exuviaella lima) and diarrhetic shellfish poisoning (DSP) risk assessment in the Gulf of California, Mexico.

A benthic toxic dinoflagellate identified as Prorocentrum lima (Syn. Exuviaella lima), and designated as strain PRL-1, was isolated from the coast of El Pardito (Coyote) Island in Baja California Sur, Mexico, after a fisherman poisoning incident involving consumption of liver from Lutjanus colorado, and Mycteroperca prionura fish. Purification and culturing was done in ES-Si medium, under 12:12 light/dark cycle (4 x 20 W cool-white fluorescent lamps), at 22 degrees C and constant stirring during 28 days. Whole cells were toxic to Artemia franciscana and its methanolic extract to mouse and to the marine yeast Debaryomyces hansenii. Chromatographic analysis (TLC and HPLC-MS) of such extract indicated an unusual proportion (1:2) okadaic acid (OA) and dinophysistoxin-1 (DTX-1). Estimated total toxin content by mouse bioassay (based on OA toxicity) was 19 pg/cell, a value significantly higher than that found by HPLC-MS (about 5.2 pg/cell, taking into account OA and DTX-1 only), suggesting that additional toxic components of unidentified nature are detected with the bioassay. This is the first report of a successful isolation and culturing of a toxic dinoflagellate from the Gulf of California, Mexico.