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971.
Chin K Onishi S Yuji M Inamoto T Qi WM Yamamoto K Warita K Yokoyama T Hoshi N Kitagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(2):193-199
Our previous study clarified that the apical regions of both the follicle-associated epithelium (FAE) of Peyer's patches and the intestinal villi are the only adhesion sites of indigenous bacteria in rat jejuno-ileum. To survey the ligands against bacterial lectins, sugar expression patterns on epithelial cells were lectin-histochemically investigated using 21 lectins in the jejuno-ileal Peyer's patches of rats. As a result, (D-glcNAc)(2-4), detected by Solanum tuberosum (STL) and by Lycopersicon esculentum (LEL), and beta-D-gal(1-3)-D-galNAc detected by Peanut agglutinin (PNA), were strongly expressed on the brush borders of the apical regions of the FAE and the intestinal villi. On the other hand, neither sugar was expressed on the brush borders of the basal regions of both FAE and intestinal villi. The positive intensities for the lectins correlated with the progression of epithelial apoptosis in the FAE and in the intestinal villi. Moreover, the double staining with lectin histochemical method and the in situ nick end-labeling method could simultaneously detect the strong expression of both sugars and nuclear DNA fragmentation in epithelial cells at the late apoptotic stage. Other sugar expression patterns in the intestinal villi were similar with those in the FAE. There were no lectins specific for M cells in the FAE. From these findings, the possible sugars of ligands against some indigenous bacterial lectins, expressing specially on the apoptotic epithelial cells, might be narrowed down in rat jejuno-ileum. 相似文献
972.
Tadashi Sakai Hisashi Murata Makoto Endo Toshiyuki Shimomura Kiyoshi Yamauchi Takafumi Ito Tokio Yamaguchi Hiroshi Nakajima Mikio Fukudome 《Aquaculture (Amsterdam, Netherlands)》1998,160(3-4):205-214
The jaundiced yellowtail Seriola quinqueradiata had yellow discolored skin and hyperbilirubinemia. Histology revealed that hemosiderin and ceroid occurred in the spleen. In the vascular system, there were vasculitis and sinusoidal dilatation. Hepatic cells showed degenerative figures with pyknotic or karyolytic nuclei, basophilic cytoplasm, cytoplasmic vacuoles in various sizes, and ceroidosis. In the bile duct system, however, there was no noticeable change. Hemoglobin contents of jaundiced fish were similar to those of control fish. Plasma taurine levels of jaundiced fish were significantly lower than those of control (p0.05). Judging from 2-thiobarbituric acid reactive substance values, in vivo lipid peroxidation progressed in the liver of jaundiced fish. In the plasma of jaundiced fish, contents of unconjugated bilirubin were significantly higher than those of conjugated bilirubin. A large amount of substance Xs, breakdown products of bilirubin scavenging active oxygen species, existed in the plasma of jaundiced fish. Therefore, jaundiced fish may suffer from severe oxidative stress, which might be a principal cause of jaundice. Liver superoxide dismutase and glutathione peroxidase activities of jaundiced yellowtail were significantly lower than those of controls. 相似文献
973.
We investigated the origin of dissolved free amino acids (DFAA) in stream water focusing on biofilms in the river bed by means
of incubation experiments in the laboratory. Stones were placed in the Toyohira River, Hokkaido, Japan, for 3 months, allowing
formation of biofilms, and then incubated for 24 h in the laboratory at stream water temperature. After incubation, the composition
and concentrations of DFAA in the incubation solution and total hydrolyzed amino acids (THAA) in biofilms were measured by
high-performance liquid chromatography. The amount of chlorophyll a (Chl. a) and the number of bacteria were also measured. The DFAA concentration increased greatly in the biofilm incubation solution,
but the DFAA composition (mol %) did not change relative to the inception of incubation, where it was similar to stream water.
There was no correlation between the increase in DFAA concentration and the THAA concentration, Chl. a amount, or the number of bacteria in biofilms. These results suggest that biofilms are one of the major sources of DFAA in
stream water. 相似文献
974.
The brain nanopeptide arginine vasotocin (AVT) and its mammalian homolog arginine vasopressin are involved in the regulation
of social and reproductive behavior. We investigated the relationship between social rank formation and the brain AVT system
in the false clown anemonefish (Amphiprion ocellaris), which forms a social rank that leads to sex differentiation in higher-ranked individuals. Tanks of three sexually immature
fish were kept for 90 days and each fish’s behavior was observed once a month. The social rank of each individual was distinguishable
by behavior, but gonadosomatic index (GSI) did not differ significantly. The number of AVT neurons in the magnocellular layer
in the preoptic area (POA) increased in subordinate individuals and declined with increasing hierarchical dominance. These
results suggest that social rank formation modulates AVT production in the brain of the clown anemonefish and may influence
their later sex differentiation. 相似文献
975.
Vu Minh DUC Rina KAKIUCHI Takeshi OBI Hiroshi ASAKURA Takehisa CHUMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):414
This study aimed to analyze the incidence of Campylobacter in a small-scale chicken meat processing plant producing “chicken-sashimi”, and determine the effectiveness of surface burning as a treatment during processing. The most probable number (MPN) method was used to analyze the load of Campylobacter in 48 samples from four different processing steps (de-feathering, chilling, surface burning, and final-products; 12 samples each). We found the highest load of isolated bacteria in chicken skin after de-feathering. Campylobacter was not detected after the surface burning step despite a large load of bacteria present in the cecum content. Campylobacter was absent in the final products. Adequate surface burning can avoid Campylobacter contamination of chicken sashimi in the processing plant by applying the external stripping method. 相似文献
976.
Evaluation of aroma compounds contributing to muskmelon flavor in Porapak Q extracts by aroma extract dilution analysis 总被引:1,自引:0,他引:1
Hayata Y Sakamoto T Maneerat C Li X Kozuka H Sakamoto K 《Journal of agricultural and food chemistry》2003,51(11):3415-3418
The flavor of the Miyabi variety of Japanese muskmelon was extracted according to the Porapak Q column method (PQM) and evaluated by using aroma extract dilution analysis (AEDA) method. The overall odor of the PQM extracts was perceived as having a natural muskmelon-like odor, suggesting that the PQM was able to extract volatile compounds in muskmelon fruit without degradation of original flavor. Forty-six odorant compounds [Kovats index (KI), 961 < or = KI < or = 2605] were found by GC-sniffing in PQM extracts, confirming the effectiveness of PQM in trapping a wide range of volatile compounds in muskmelon flavor. The 46 odorants could be divided into three groups on the basis of their odor attributes: fruity note (KI < 1300); green, grassy, or cucumber-like note (1300 < KI < 2020); and sweet note (KI > 2020). When the original extracts were diluted in AEDA analysis, seven odorants could still be detected by GC-sniffing at a flavor diluation (FD) factor of 128 or above: one had a fruity note (compound 3); four had a cucumber-like, green, or grassy note (compounds 12, 17, 21, and 23); and two had a sweet note (caramel-like or yakitori-like) (compounds 32 and 34). 相似文献
977.
We quantitatively evaluated the cumulative ecological risks from multiple pesticides used in paddy fields in Japan. Moreover, we visualized the temporal and regional variability of those risks for 1990–2010. Considering the region-specific parameters of environmental conditions, region-specific predicted environmental concentrations were estimated at 350 river-flow monitoring sites in Japan. Then the multi-substance potentially affected fraction (msPAF) was calculated as a risk index of multiple pesticides by using the computation tool NIAES-CERAP. The median msPAF values for insecticides and herbicides decreased by 92.4% and 53.1%, respectively, from 1990 to 2010. This substantial reduction in ecological risk was attributed to the development of low-risk pesticides by manufacturers, the efforts of farmers in risk reduction, and tighter regulation by the Japanese government. In particular, the substantial reduction of the ecological risk from insecticides was largely due to the decrease in the use of organophosphorus insecticides. 相似文献
978.
Muhammad Naeem Mushtaq Yukari Sunohara Hiroshi Matsumoto 《Weed Biology and Management》2013,13(4):129-134
l ‐3,4‐dihydroxyphenylalanine (l ‐DOPA) is a bioactive natural compound that inhibits the growth of several plant and weed species. However, its mode of action is not yet well understood in plants. The present study was conducted to explore the mechanism of growth inhibition by l ‐DOPA in lettuce (Lactuca sativa L.). The results revealed that l ‐DOPA induced cell death and inhibited the root growth of lettuce. Moreover, 0.1 mmol L–1 l ‐DOPA enhanced the polyphenol oxidase activity, production of reactive oxygen species ( and H2O2) and lipid peroxidation in the lettuce roots. The results suggest that l ‐DOPA‐induced growth inhibition in lettuce roots might be related to oxidative stress. 相似文献
979.
980.
Hiroshi AKAIKE Makoto NAGAI Alexandre Tomomitsu OKATANI Yukio MORITA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(7):924
This study examined the safety and productivity data analysis of a dairy farm over a 3-year period following the implementation of a Hazard Analysis and Critical Control Point (HACCP) system in 2018. The CCP was “the selection of milking cows” and the critical limit was “the withholding period has passed”. No deviation from the critical limit was observed, the safety of the milk is ensured. In addition, the average daily milk yield per cow increased, while the average number of somatic cells/ml decreased. The number of cows with newly diagnosed mastitis increased, and the product excluded. These results suggest that the HACCP system had a positive effect on milk yield per cow and led to a decrease in somatic cells. 相似文献