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121.
The proliferative potential of a spinal nephroblastoma was studied in a young dog. A 4-month-old, female golden retriever showed developing deterioration in her gait and subsequent paralysis of her hind legs. At necropsy, a well-demarcated grayish brown tumor mass was found in the lumbar spinal cord segments between L2 and L3. Histologically, a blastemal cell tumor with a tubule- or glomeruli-like structure was found to be infiltrating intradurally. Proliferating cells at the S-phase, assessed using the bromodeoxyuridine (BrdU) labeling method, were seen occasionally in the tubular cells and glomeruli-like structures and were frequently seen in the blastemal cells. Immunohistochemically, the tubular epithelial cells were positive for cytokeratin, and the blastemal cells were positive for vimentin. The present tumor showed a high potential for growth and invasion, which suggests that it the potential to expand into the adjacent spinal cord. 相似文献
122.
Doki M Fujita K Miura R Yoneda M Ishikawa Y Taneno A Kai C 《Comparative immunology, microbiology and infectious diseases》2006,29(4):199-206
Seven strains of canine parvovirus (CPV) were isolated from affected dogs in Japan between 1999 and 2000, and their VP2 genes were genetically analyzed. Comparison of the predicted amino acid sequences of VP2 suggested that three field isolates corresponded to CPV type 2a, while the other four to CPV type 2b. The phylogenetic tree constructed from the VP2 genes showed that the newly isolated strains are classified into the cluster consisting of recent Japanese and Taiwanese field isolates, which are distinct from Vietnamese isolates, United States Isolates, or classical CPV type 2. These results suggest that the CPV transmission occurred between Japan and Taiwan in 1990s, and the offspring are still circulating in both countries. 相似文献
123.
Anzai M Nishiwaki M Yanagi M Nakashima T Kaneko T Taguchi Y Tokoro M Shin SW Mitani T Kato H Matsumoto K Nakagata N Iritani A 《The Journal of reproduction and development》2006,52(5):601-606
Development of assisted reproductive technologies is necessary to obtain fertilized oocytes in a subfertile transgenic mouse strain. Here, we showed the application of laser-assisted drilling of the zona pellucida to in vitro fertilization of cryopreserved mouse oocytes with sperm from subfertile transgenic mice (C57BL/6N-Tg(UCP/FAD2)U8 strain). After cryopreservation by vitrification, the recovery and survival rates of the zona-drilled mouse oocytes were 97% (97/100) and 94% (91/97), respectively. In vitro fertilization of the cryopreserved zona-drilled mouse oocytes with sperm from the subfertile transgenic mice was greatly facilitated (60%, 55/91) compared to that of the cryopreserved zona-intact mouse oocytes (11%, 81/768). In vitro fertilized embryos that developed to the 2-cell stage were again cryopreserved by vitrification, and after warming they were transferred into recipient females. Subsequently, six viable offspring were delivered, and all were confirmed to be transgenic mice. These results indicate that laser-assisted zona drilling of oocytes combined with cryopreservation by vitrification may be a useful approach for large-scale production of in vitro fertilized embryos for managing transgenic mouse strains with reproductive disabilities such as subfertile sperm. 相似文献
124.
Villarroel A Morley PS Wittum TE Bolte DS 《American journal of veterinary research》2006,67(6):951-956
OBJECTIVE: To evaluate various sampling strategies for potential use in measuring prevalence of antimicrobial susceptibility in cattle. SAMPLE POPULATION: 500 isolates of non-type-specific Escherichia coli (NTSEC) isolated from the feces of 50 cows from 2 dairy farms (25 cows/farm and 10 isolates/cow). PROCEDURES: Diameters of inhibition zones for 12 antimicrobials were analyzed to estimate variation among isolates, cows, and farms and then used to determine sampling distributions for a stochastic simulation model to evaluate 4 sampling strategies. These theoretic sampling strategies used a total of 100 isolates in 4 allocations (1 isolate from 100 cows, 2 isolates from 50 cows, 3 isolates from 33 cows, or 4 isolates from 25 cows). RESULTS: Analysis of variance composition revealed that 74.2% of variation was attributable to isolates, 18.5% to cows, and 7.3% to farms. Analysis of results of simulations suggested that when most of the variance was attributable to differences among isolates within a cow, culturing 1 isolate from each of 100 cows underestimated overall prevalence, compared with results for culturing more isolates per cow from fewer cows. When variance was not primarily attributable to differences among isolates, all 4 sampling strategies yielded similar results. CONCLUSIONS AND CLINICAL RELEVANCE: It is not always possible to predict the hierarchical level at which clustering will have its greatest impact on observed susceptibility distributions. Results suggested that sampling strategies that use testing of 3 or 4 isolates/cow from a representative sample of all animals better characterize herd prevalence of antimicrobial resistance when impacted by clustering. 相似文献
125.
Edoardo Capuano Giovanna Garofalo Aurora Napolitano Henryk Zielinski Vincenzo Fogliano 《Cereal Chemistry》2010,87(2):131-136
This report shows the effect of rye flour extraction rate on Maillard reaction, antioxidant activity, and acrylamide formation during toasting of rye bread crisps. Four rye flours with extraction rates of 70, 85, 95, and 100% were tested. Maillard reaction development was studied by measuring browning development, hydroxymethylfurfural (HMF), and glucosilisomaltol (GIM) formation, as well as antioxidant activity. Results showed that HMF and GIM concentrations in toasted bread crisps were higher as the flour extraction rate increases. Antioxidant activity increased during toasting as a consequence of antioxidant Maillard reaction product formation. Acrylamide concentration was clearly affected by free asparagine content of flour, while no effect of dietary fiber and natural antioxidant content of flours had an effect on acrylamide formation. Overall data suggest that the rate of Maillard reaction is higher in whole flours because of their higher free amino acid and protein content. 相似文献
126.
Capuano E Fedele F Mennella C Visciano M Napolitano A Lanzuise S Ruocco M Lorito M del Castillo MD Fogliano V 《Journal of agricultural and food chemistry》2007,55(10):4189-4195
Amadoriase I is a fructosyl amine oxidase from Aspergillus fumigatus that catalyzes the oxidation of Amadori products (APs) producing glucosone, H2O2, and the corresponding free amine. All the enzymes of this family discovered so far only deglycate small molecular weight products and are inactive toward large molecular weight substrates, such as glycated BSA or ribonuclease A. Therefore, they cannot be used to reverse protein glycation occurring in diabetes or in foods. In this paper, the effect of Amadoriase I added during the in vitro reaction between glucose and peptides having different polarities or proteins with molecular weights ranging from to 5 to 66 kDa was tested. The formation of APs was monitored by ESI-MS of intact glycated protein or peptides and by measuring the Nepsilon-(1-deoxy-d-fructos-1-yl)-L-lysine and furosine concentrations. Results showed that the formation of APs is reduced up to 80% when peptides and glucose are incubated in the presence of Amadoriase. The effect is more evident for hydrophobic peptides. In protein-glucose systems, the effect was dependent on the molecular weight and steric hindrance being negligible for BSA and at a maximum for insulin, where the formation of APs was reduced up to 60%. These findings indicate new potential applications of Amadoriase I as an efficient tool for inhibiting protein glycation in real food systems. 相似文献
127.
Tomomi Kanehara Naoko Matsui Mami Murakami Kohji Maruo Takashi Mori Akihiro Hirata Tokuma Yanai Hiroki Sakai 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(2):356-360
A 12‐year‐old, male castrated Domestic Shorthair cat was presented to Animal Medical Center of Gifu Univeristy with anorexia and vomiting. Physical examination revealed an enlarged left tonsil and right mandibular lymph node (approximately 2–3× the normal size), and a submucosal mass on the right side of the epiglottis (1.5 × 2.0 cm). On computed tomography images, an enlarged left tonsil, and enlarged right mandibular, right pharyngeal, and left and right cervical lymph nodes were observed. Cytologic examination of smears of tonsil and lymph nodes revealed numerous medium‐ to large‐sized neoplastic lymphoid cells, approximately half of which contained one or several light‐blue homogenous globoid cytoplasmic inclusions (5–10 μm), which stained magenta with periodic acid–Schiff (PAS) stain. Histopathologic examination of the left tonsil revealed diffuse proliferation of medium‐ to large‐sized neoplastic lymphoid cells effacing the original lymphoid architecture. Half of the cells contained one or several eosinophilic globoid cytoplasmic inclusions, which stained magenta with PAS and showed positive immunohistochemical reactions for immunoglobulin M (IgM) and λ light chain. Neoplastic lymphoid cells were also CD20+, Pax5+, and MUM1+, and CD3?. Thus, the neoplastic lymphoid cells expressed a B‐cell immunophenotype, and the globoid cytoplasmic inclusions represented an aberrant IgM λ light chain accumulation, similar to Russell bodies. B‐cell lymphoma with Mott cell differentiation was diagnosed based on cytologic, histopathologic, and immunohistochemical features. This is the first report of B‐cell lymphoma with Mott cell differentiation in a cat. 相似文献
128.
Boniface Baboreka KAYANG Miho INOUE-MURAYAMA Hideaki TAKAHASHI Mitsuru MINEZAWA Masaoki TSUDZUKI Makoto MIZUTANI Shin'ichi ITO 《Animal Science Journal》2003,74(4):255-259
Twenty‐eight original chicken microsatellite markers were isolated and characterized to determine their utility as cross‐reactive markers for comparative genetic mapping in the order Galliformes. Primer pairs were typed in 12 unrelated chickens and also tested on Japanese quail and helmeted guinea fowl deoxyribonucleic acid (DNA). Polymorphism was observed in 23 (82.1%) of the markers and the average number of alleles per locus was 2.9 while the mean heterozygosity was 0.19. Eleven (39.3%) of the chicken markers cross‐reacted with Japanese quail DNA and 2 (7.1%) with helmeted guinea fowl DNA. The cross‐reactive markers described would serve as useful resources for comparative genetic mapping in poultry species belonging to the order Galliformes. 相似文献
129.
Borrelli RC Esposito F Napolitano A Ritieni A Fogliano V 《Journal of agricultural and food chemistry》2004,52(5):1338-1343
Dietary fiber (DF) is one of the main dietary factors contributing to consumers' well-being. In this work the possibility of using the roasted coffee silverskin (CS), a byproduct of roasted coffee beans, as a DF-rich ingredient has been evaluated. The results of our investigation showed that this material has 60% total DF, with a relevant component (14%) of soluble DF. Although a small amount of free phenol compounds is present in CS, it has a marked antioxidative activity, which can be attributed to the huge amount of Maillard reaction products, the melanoidins. Static batch culture fermentation experiments showed that CS induces preferential growth of bifidobacteria rather than clostridia and Bacteroides spp. CS can be proposed as a new potential functional ingredient in consideration of the high content of soluble DF, the marked antioxidant activity, and the potential prebiotic activity. 相似文献
130.
The Effects of AlCl3 Additions on Rhizosphere Soil and Fine Root Chemistry of Sugar Maple (Acer Saccharum) 总被引:1,自引:0,他引:1
Increased Al mobilization and Ca and Mg leaching have been linked to nutritional imbalances in sugar maple across the northeastern US and Canada. The susceptibility of sugar maple fine roots to Al stress is poorly understood, in part because roots respond to Al stress by altering the chemistry of the rhizosphere. AlCl3 was applied to plots of sugar maple at the Hubbard Brook Experimental Forest, NH. After two years of treatment, we sampled fine roots of sugar maple, rhizosphere soil, and bulk soil in the Oa horizon and the upper 10 cm of the mineral soil. AlCl3 treatments resulted in significantly less Ca (21%) and Mg (30%) in fine roots from the organic horizon, but had no significant effect on fine root Al. Fine root (Ca+Mg):Al ratios were 42% lower in AlCl3 plots than in controls, though most roots had ratios above critical toxicity thresholds developed for hydroponically grown sugar maple seedlings. In the mineral horizon, roots differed only in Mg concentration, which was 22% lower in AlCl3 plots. In the AlCl3 treated plots, rhizosphere soil in the organic horizon had 47% greater Al and 29% less Mg than in controls. Combining data from both treatments we found significantly less Al and organically bound Al in rhizosphere soil than in bulk soil, possibly due to leaching of Al from the rhizosphere by organic acids released by roots. These results suggest that increased mobilization of Al in soil lowers (Ca+Mg):Al ratios in sugar maple fine roots, though roots may minimize Al stress by leaching Al from the rhizosphere. 相似文献