The influence of porcine epidemic diarrhea virus on pig small intestine mucosal epithelial cell function.

Porcine epidemic diarrhea (PED) is a highly contagious, acute enteric tract infectious disease of pigs (Sus domesticus) caused by porcine epidemic diarrhea virus (PEDV). PED is characterized by watery diarrhea, dehydration, weight loss, vomiting and death. PEDV damages pig intestinal epithelial tissue, causing intestinal hyperemia and atrophy of intestinal villi, with formation of intestinal epithelial cell cytoplasmic vacuoles. Since pig small intestinal epithelial cells (IECs) are target cells of PEDV infection, IEC cells were utilized as a model for studying changes in cellular activities post-PEDV infection. Monitoring of Na+-K+-ATPase and Ca2+-Mg2+-ATPase activities demonstrated that PEDV infection decreased these activities. In addition, IECs proliferation was shown to decrease after PEDV infection using an MTT assay. Moreover, IECs apoptosis detected by flow cytometry with propidium iodide (PI) staining was clearly shown to increase relative to the control group. Meanwhile, animal experiments indicated that PEDV virulence for IEC cells was greater than viral virulence for Vero cells, although this may be due to viral attenuation after numerous passages in the latter cell line. Collectively, these studies revealed viral pathogenic mechanisms in PEDV-infected IECs and offer a theoretical basis for PEDV prevention and control.

Frequency of Polycythemia and Other Abnormalities in a Tibetan Herdsmen Population Residing in the Kham Area of Sichuan Province, China.

INTRODUCTION: The Kham Tibetans are one of several Tibetan ethnic subgroups living in the Kham area of China. Because studies on the high-altitude adaptation of the Kham people are scant, the main aim of this study is to investigate whether the response to hypoxia, especially polycythemia status, in the Kham Tibetans is different from other Tibetan ethnic subgroups. METHODS: The primary investigation was conducted on 346 native Kham Tibetan adults (268 men and 78 women) from 3 herdsmen villages located in Hongyuan County situated at an altitude of greater than 3600 m. The participants were aged 46.2±14.1 (21-82; mean±SD with range) years. Anthropometric measurements such as weight, height, waist circumference, body mass index, and blood pressure, as well as laboratory blood tests such as glycosylated hemoglobin, hemoglobin, total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and uric acid were analyzed. RESULTS: The concentrations of hemoglobin were 171.3±12.9 (66-229) mg·L-1 and 151.4±16.4 (86-190) mg·L-1 in men and women, respectively. The frequency of polycythemia was found to be 25.5 and 21.8% in men and women, respectively. Polycythemia was found to be significantly associated with glycosylated hemoglobin concentrations, hypertension, and hyperuricemia (P=0.002, 0.023, and 0.009, respectively). CONCLUSIONS: There is a higher frequency of polycythemia in the Kham Tibetans when compared with reported studies from other Tibetan ethnic subgroups living on the Qinghai-Tibet plateau.