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101.
Yusaku Tsugami Norihiro Suzuki Manabu Kawahara Takahiro Suzuki Takanori Nishimura Ken Kobayashi 《Animal Science Journal》2020,91(1)
This study attempted to establish a culture model to recreate the milk production pathway in bovine mammary epithelial cells (BMECs). BMECs were isolated from Holstein cows (nonlactating, nonpregnant, and parous) and were stored by cryopreservation. To separate the apical and basolateral compartments, BMECs were cultured on a cell culture insert with a collagen gel in the presence of bovine pituitary extract and dexamethasone to induce milk production and tight junction (TJ) formation. The culture model showed the secretion of the major milk components, such as β‐casein, lactose, and triglyceride, and formed less‐permeable TJs in BMECs. Moreover, the TJs were distinctly separated from the apical and basolateral membranes. Glucose transporter‐1, which transports glucose into the cytoplasm through the basolateral membrane, localized in the lateral membrane of BMECs. Toll‐like receptor‐4, which binds to lipopolysaccharide in the alveolar lumen in mastitis, localized in the apical membrane. Beta‐casein was mainly localized near the Golgi apparatus and the apical membrane. Moreover, milk components were almost secreted into the upper chamber of the cell culture insert. These findings indicate that this model has clear cell polarity as well as in vivo and is effective to study of milk production and the blood–milk barrier in lactating BMECs. 相似文献
102.
103.
Equine group A rotavirus (RVA) strain H-1 (RVA/Horse-tc/GBR/H-1/1975/G5P9[7]) was found to have VP4, VP6-7, NSP1 and NSP4 genes of porcine origin. In order to obtain conclusive information on the exact origin and evolution of this unusual equine strain, the remaining six genes (VP1-3, NSP2-3 and NSP5 genes) of strain H-1 were analyzed in the present study. By whole genomic analysis, strain H-1 exhibited a porcine RVA-like genotype constellation (G5-P[7]-I5-R1-C1-M1-A8-N1-T1-E1-H1), different from those of typical equine RVA strains. The VP2-3 and NSP2-3 genes of strain H-1 were found to originate from porcine RVAs. On the other hand, it was difficult to pinpoint the exact origin of the VP1 and NSP5 genes of strain H-1, though phylogenetically, these genes appeared to be possibly derived from porcine or Wa-like human strains. Taken together, at least nine (VP2-4, VP6-7 and NSP1-4 genes) of the 11 gene segments of strain H-1 were found to be of porcine origin, revealing a porcine RVA-like genetic backbone. Therefore, strain H-1 is likely a porcine RVA strain that was transmitted to horses. 相似文献
104.
K Ohara Y Kobayashi N Tsuchiya H Furuoka T Matsui 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(10):1127-1130
A 5-month-old, male, Shih Tzu dog manifesting polyuria and polydipsia since 2-month-old was presented to our hospital with additional clinical complaints of vomiting and depression during recent a few days. Despite the symptomatic therapy for chronic renal failure, he died on the day after medication. Macroscopically, both kidneys were small in size with rough surface. Microscopical examination revealed bilateral renal fibrosis with dysplastic changes consisting of immature glomeruli and tubules, and foci of adenomatoid proliferation of tubular epithelium. In addition, incomplete lobulation of medulla with pelvic structures was also noticed in the right kidney. From these findings, the present case was diagnosed as renal dysplasia in Shih Tzu dog which was documented in the literatures. 相似文献
105.
106.
Treatment by Sivanesan and Gibson (1976), that combined all species of Entomosporium into one species E. mespili (DC. ex Duby) Sacc, was supported through the investigation of many exsiccati and fresh specimens.Morphologically, all specimens and isolates of Entomosporium, which had been differentiated into 4 species, could not be divided into clearly separated groups.The fungus has been recorded on 50 host species and the disease is widespread throughout the world. 相似文献
107.
LIZhao-hua MikioKOBAYASHI 《林业研究》2004,15(3):233-242
In the past, utilization of bamboo resources in China has been traditionally dominated by direct consumption of local farmers as minor forest products with weak linkage with market. In recent years, the over-supply of grains and rapid degradation of agricultural environment call for alternative crops that can be developed through integrating the environmental plantation with the market demands. Closely associated with forestry and agriculture, bamboo is able to deal with the new challenges which China‘s agriculture is facing. Of 534 documented bamboo species in China, 153 species produce edibleshoots and of which 56 species are recommended for agricultural plantation; 139 species provide timbers and of which 58 species recommended; 116 species can be splited as good strips for weaving and of which 22 species recommended; 88 species are considered as garden bamboos and of which 34 species recommended; 45 species are able to produce paper pulp and of which 18 species recommended. 相似文献
108.
Shigeki Yoshida Atsushi Kuno Naoto Saito Masakazu Aoyama Isao Kusakabe 《Journal of Wood Science》1998,44(6):457-462
Xylan prepared from culms of kumaizasa (Sasa senanensis Rehd.), a representative species of bamboo grass, was hydrolyzed with-xylanase ofStreptomyces olivaceoviridis E-86. Four arabinoxylo-oligosaccharides and two glucuronoxylo-oligosaccharides were isolated from the enzymatic hydrolysate of the xylan by chromatography on a charcoal column, a Dowex 1-x8 column, a Toyo-pearl HW-40S column, and a LiChrospher 100 NH2 column and on preparative paper chromatography. The results of the structural analyses of the saccharides showed that the isolated oligosaccharides had the structures of 32--l-arabinofuranosyl-xylobiose, 32--l-arabinofuranosyl-xylotriose, 32--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylobiose, 33--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylotriose, 23--4-O-methyl-d-glucuronosyl-xylotriose, and 23--d-glucuronosyl-xylotriose. From the structural analysis of the oligosaccharides derived from the xylan, kumaizasa xylan was concluded to be a kind of arabinoglucuronoxylan having not only stubs of singlel-arabinose and singled-glucuronic acid but also stubs of disaccharide units such as-d-xylopyranosyl-(1 2)-l-arabinofuranose. 相似文献
109.
Ken Watanabe Yasuhiro Matsushita Isao Kobayashi Naohiro Kuroda 《Journal of Wood Science》2013,59(2):112-118
Sugi (Cryptomeria japonica D. Don) lumber is known to have a large variability in final moisture content (MCf) and is difficult to dry. This study assessed the capability of artificial neural networks (ANNs) to predict the MCf of individual wood samples. An ANN model was developed based on initial moisture content, basic density, annual ring orientation, annual ring width, heartwood ratio and lightness (L * in the CIE L * a * b * system). The performance of the ANN model was compared with a principal component regression (PCR) model. The ANN model showed good agreement with the experimentally measured MCf with a higher correlation coefficient (r) and a lower root mean square error (RMSE) than the PCR model, demonstrating the importance of nonlinearity of the variables and the higher capability of the ANN model than the PCR model. By adding redness (a * ) and yellowness (b * ) and drying time to the input variables of ANNs, r and RMSE values were improved to 0.98 and 1.2 % for the training data set, and 0.85 and 2.2 % for the testing data set, respectively. Although the developed ANNs are available under the limited conditions of this study, our results suggest that the ANNs proposed offer reliable models and powerful prediction capability for the MCf, even though wood properties vary considerably and their complex interrelations are not fully elucidated. 相似文献
110.
Summary A light microscopic (LM) visual technique to determine the polyethylenimine (PEI) distribution in a wood-PEI composite was studied by the adsorption of acid red or the circulation of Cu(II) ion with PEI in the composite. The amount of the adsorbed dye or Cu(II) on the composite increased linearly with an increase in the PEI content of the wood-PEI. The dyed composites were observed with LM under monochromatic light, corresponding to their absorption maxima at 560 nm for acid red and at 640 nm for copper chelate. The microscopic image was photographically recorded and the negative was subjected to densitometric analysis. At a polymer content lower than 4% in the composite, about 70% of total polymer was located in the middle lamella region, leaving only 30% in the secondary wall. With increasing PEI content of the composite, the concentration in the secondary wall increased, and about 80% of the polymer was located in the secondary wall at a PEI content of 27%. There were no noticeable differences between the amount of polymer detected by dyeing with acid red and by chelating with Cu(II). From the results of the line analysis of the intensity of the characteristic X-ray of uranium, the distribution of the PEI in the cell wall agreed closely with that determined by the LM method. It was concluded that the LM visual technique to determine the PEI location in the wood-PEI composite by dyeing with acid red or by chelating with Cu(II) is a simple and reliable method. 相似文献