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BACKGROUND & AIMS: Nutrients and properties of lipases affect survival of lipolytic activity during aboral gastrointestinal transit. Whether different doses and formulations of bacterial lipase and diets affect steatorrhea was tested in pancreatic-insufficient dogs. METHODS: A dose of 0-600,000 IU of powdered and 135,000 and 300,000 IU of liquid bacterial lipase was given with a standard meal to 5 dogs with ligated pancreatic ducts. In 4 dogs, 0 or 300,000 IU (normal 6-hour postprandial amount) of powder bacterial lipase was also given with five meals containing 850 kcal with different nutrient caloric densities (mixture design). Coefficients of fat absorption during 72- hour fecal balance studies were used to assess treatments. RESULTS: With the standard meal, powder bacterial lipase reduced steatorrhea in a dose-dependent manner (P = 0.03), and 135,000 and 300,000 IU of the liquid form decreased steatorrhea more than powder bacterial lipase (P = 0.017 and 0.057, respectively). Coefficients of fat absorption with 300,000 IU of powder bacterial lipase correlated (r2 = 0.79; P < 0.001) with increasing proportions of fat calories in diets. CONCLUSIONS: Liquid bacterial lipase decreases steatorrhea more than powder, and 300,000 IU of powder bacterial lipase ingested with high-fat meals corrects canine pancreatic steatorrhea. The combination of adequate mixing of small amounts (milligrams) of bacterial lipase and high-fat meals abolishes canine steatorrhea and may abolish human pancreatic steatorrhea. (Gastroenterology 1997 Jun;112(6):2048-55) 相似文献
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This paper reviews a decade of collaborative studies performed between two laboratories in Germany and Australia on the life cycle, pathogenicity and immunology of infections by the cyst-forming sporozoan parasites Sarcocystis spp. in domestic animals. Experimental transmission studies demonstrated that certain parasite species could cause an acute clinical disease in sheep and pigs severely affecting their health, productivity and reproductivity. Despite the high prevalence of infections found in farm animals, few outbreaks of naturally-occurring clinical disease have ever been recorded. Host animals exposed to low levels of infection were found to develop a strong protective immunity against subsequent lethal challenge and clinical disease even though parasites were not completely eliminated nor prevented from further establishment (premunitive immunity rather than sterile immunity). Modern molecular biological techniques are currently being used to examine the parasite antigens and host immune responses involved in the acquisition of the protective immunity. 相似文献