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The toxic effects of Ipomoea carnea subsp. fistulosa were evaluated in guinea pigs by administration of dry leaves during 45 days. Swainsonine and calystegines B1, B2 and C1 were isolated and quantified. Clinical signs included emaciated and loss of body weight. Histological evaluation demonstrates numerous vacuoles in the cytoplasm of pancreas, liver and renal cells. Vacuolation was also evident in neurons of brain stem, mainly pontine nuclei. Neuronal lectin binding pattern showed a strong positive reaction to Con-A (Concanavalia ensiformis), WGA (Triticum vulgaris), sWGA (succinylated T. vulgaris) and LCA (Lens culinary). This result is coincident with the lectin histochemistry staining pattern of the vacuoles described in CNS of ruminants. We conclude that I. carnea subsp. fistulosa induces an intralysosomal accumulation of mannose-containing oligosaccharides in guinea pigs, which makes it a valuable animal model for the reproduction of induced α-mannosidosis.  相似文献   
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T-cell epitopes of porcine reproductive and respiratory syndrome virus (PRRSV) glycoproteins 4 (GP4), 5 (GP5) and nucleocapsid (N) were predicted using bioinformatics and later tested by IFN-γ ELISPOT in pigs immunized with either a modified live vaccine (MLV) or DNA (open reading frames 4, 5 or 7). For MLV-vaccinated pigs, immunodominant epitopes were found in N but T-epitopes were also found in GP4 and GP5. For DNA-immunized pigs, some peptides were differently recognized. Using a large set of PRRSV sequences it was shown that N contains a conserved epitope and that for GP5, the genotype-I counterparts of previously reported epitopes of genotype-II strains were also immunogenic.  相似文献   
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BACKGROUND/AIMS: Intraductal papillary-mucinous tumor of the pancreas is currently considered to be a tumor which is an entity of its own, different from classic pancreatic ductal carcinoma. It is basically characterized by slow growth and low malignancy potential, as well as by the production of mucin. The aim of this study is to contribute to world literature some clarification of its natural history, clinical presentation, the most useful diagnostic tests, methods of detection of stromal invasion and handling of treatment. METHODOLOGY: Of 297 pancreatectomies undertaken at the "12 de Octubre" hospital between May 1985 and January 1998, only 1 case of Intraductal papillary-mucinous tumor was found. We have revised 127 cases published in 10 series over the last 10 years. We also contribute a review of our own case. RESULTS: These tumors, which are very infrequent, produce non-specific symptoms, with long latency periods from the first symptom up to stromal invasion. Endoscopic retrograde cholangiopancreatography showed alterations in 100% of cases where this was undertaken. Tumor-related mortality was zero amongst patients with non-invasive tumor who underwent surgery. None of the cases published presented upper gastrointestinal hemorrhage. This indicated the correct surgery and led us to our diagnosis. CONCLUSIONS: We confirm the low frequency and difficulty of diagnosis, the sensitivity of endoscopic retrograde cholangiopancreatography, the difficulty of early detection of stromal invasion, and the high survival rate in cases where resection is done before this occurs. Early diagnosis and treatment is therefore of utmost importance.  相似文献   
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Diminished PGE2 levels in diabetic embryos are related to the development of malformations, and thus the aim of the present study was to determine whether PGE2 levels are modified in rat embryos cultured in diabetic serum during organogenesis, and if PGE2 content and release, and 3H-PGE2 uptake and release, are altered in incubated diabetic embryos. Rats were made diabetic by steptozotocin (60 mg kg(-1)) before mating. Control rat embryos cultured for 24 h (explantation Day 9) in the presence of diabetic serum showed diminished PGE2 levels. When Day 10 diabetic embryos were incubated, embryo PGE2 levels were lower, but the PGE2 released to the incubation media was much higher than in controls. Uptake of 3H-PGE2 by diabetic embryos was initially enhanced (5-10 min), then reached similar levels to controls (20-100 min). Release of 3H-PGE2 previously incorporated during a 60-min incubation was greater in diabetic embryos than in controls. These results show diminished PGE2 content in both diabetic and normal embryos cultured in the presence of diabetic serum, but suggest that diabetic embryos have the capability to produce and release high levels of PGE2. The enhanced release of PGE2 is probably the result of transport abnormalities, and leads to the elevated PGE2 concentrations found in the incubating medium and to the diminished intraembryonic PGE2 levels that alter embryonic development.  相似文献   
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