Molecular Detection, Multilocus Genotyping, and Population Genetics of Enterocytozoon bieneusi in Pigs in Southeastern China.

Enterocytozoon bieneusi is an important opportunistic pathogen widely distributed in humans and animals that causes diarrhea or fatal diarrhea in immunocompromised hosts. To examine the infection status and molecular characteristics of E. bieneusi in pigs, 725 fecal samples were collected from pigs in six areas of Fujian Province. The E. bieneusi genotypes were identified based on the internal transcribed spacer (ITS) regions of the ribosomal RNA (rRNA) gene by nested PCR, and its population genetics were analyzed by multilocus sequence typing (MLST). The results showed that the infection rate of E. bieneusi was 24.4% (177/725), and 11 known genotypes (EbpC, EbpA, CHN-RR2, KIN-1, CHG7, CHS5, CM11, CHG23, G, PigEBITS, and D) and 2 novel genotypes (FJF and FJS) were identified. All the genotypes were found to be clustered into zoonotic Group 1. Moreover, 52 positive samples were successfully amplified at minisatellite and microsatellite loci and formed 48 distinct multilocus genotypes (MLGs). Further population structure analyses showed strong genetic linkage disequilibrium (LD) and several recombination events (Rm), indicating that E. bieneusi has a clonal population structure. This study is the first to investigate the prevalence and molecular characteristics of E. bieneusi in Fujian Province and could provide baseline data to control E. bieneusi infection in pigs and humans and deepen our understanding of the zoonotic risk of E. bieneusi and its distribution in China.

[Effects of Rutin on Myocardial Enzyme and Cardiac Morphology in Diabetic Mice].

OBJECTIVE: To study the effects of rutin on myocardial enzyme in serum and myocardial morphology in diabetic mice induced by streptozotocin (STZ). METHODS: A model of type 1 diabetic mice was established in 48 male kunming mice with daily intraperitoneal injection of streptozotocin (STZ) 62.5 mg/kg for 5 consecutive days. 12 male Kunming mice were selected as normal group randomly. The established successfully diabetic mice were randomly divided into the model group, irbesartan group [45 mg/ (kg?d)], low-, high-dose rutin groups [50, 100 mg/ (kg?d)]. The mice in the normal and the model groups were given sodium carboxymethyl cellulose solution (CMC-Na, 1 g/L) by intragastric administration respectively. After administration for 8 weeks, the levels of creatine kinase (CK), creatine kinase isoenzymes (CK-MB), hydroxybutyrate dehydrogenase (HBDH), and lactate dehydrogenase (LDH) in serum were detected by blood biochemical analyzer. The cardiac myocardial morphology was observed by HE staining, Masson trichrome staining and electron microscope. RESULTS: Compare to the normal group, the levels of the myocardial enzyme in serum evidently increased in the model group (P<0.01); Compare to the model group, the levels of the myocardial enzyme in serum decreased in low-, high-dose rutin groups; The levels of HBDH and LDH declined remarkably in the high-dose rutin group relative to the low-dose group (P<0.05); Compared to the high-dose group, the level of LDH increased in the irbesartan group (P<0.05).Moreover, relative to the model group, the morphology of myocardial tissue, the degree of fibrosis and the ultrastructure of myocardial tissue in mice were significantly improved in low-, high-dose rutin groups, and the effects were more significant in the high-dose rutin group. CONCLUSION: Rutin could decrease the levels of myocardial enzyme in serum in diabetic mice, improve the cardiac cell morphology and alleviate myocardial injury.

Prevalence and Genetic Identification of Three Entamoeba Species in Pigs in Southeastern China.

Parasitic Entamoeba spp. can infect many classes of vertebrates including humans and pigs. Entamoeba suis and zoonotic Entamoeba polecki have been identified in pigs, and swine are implicated as potential reservoirs for Entamoeba histolytica. However, the prevalence of Entamoeba spp. in pigs in southeastern China has not been reported. In this study, 668 fecal samples collected from 6 different regions in Fujian Province, southeastern China, were analyzed to identify three Entamoeba species by nested PCR and sequencing analysis. The overall prevalence of Entamoeba spp. was 55.4% (370/668; 95% CI 51.6% to 59.2%), and the infection rate of E. polecki ST1 was the highest (302/668; 45.2%, 95% CI 41.4% to 49.0%), followed by E. polecki ST3 (228/668; 34.1%, 95% CI 30.5% to 37.7%) and E. suis (87/668; 13.0%, 95% CI 10.5% to 15.6%). E. histolytica was not detected in any samples. Moreover, the coinfection rate of E. polecki ST1 and ST3 was 25.1% (168/668; 95% CI 21.9% to 28.4%), the coinfection rate of E. polecki ST1 and E. suis was 3.7% (25/668; 95% CI 2.3% to 5.2%), the coinfection rate of E. polecki ST3 and E. suis was 0.3% (2/668), and the coinfection rate of E. polecki ST1, E. polecki ST3, and E. suis was 4.0% (27/668; 95% CI 2.5% to 5.5%). A representative sequence (MK347346) was identical to the sequence of E. suis (DQ286372). Two subtype-specific sequences (MK357717 and MK347347) were almost identical to the sequences of E. polecki ST1 (FR686383) and ST3 (AJ566411), respectively. This is the first study to survey the occurrence and to conduct molecular identification of three Entamoeba species in southeastern China. This is the first report regarding mixed infections with E. suis, E. polecki ST1, and E. polecki ST3 in China. More research studies are needed to better understand the transmission and zoonotic potential of Entamoeba spp.