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71.
We examined the effect of stroma-derived factors, hepatocyte growth factor (HGF) and leptin, on morphological differentiation of bovine mammary epithelial cells (BMEC) in collagen gel three-dimensional culture in vitro. BMEC treated with HGF, but not leptin, formed duct-like organoids. The formation of organoids by HGF was enhanced by treatment with a mixture of insulin, cortisol and prolactin, while BMEC treated with the mixture alone did not produce the organoid. In contrast, the formation of organoids by HGF was dose-dependently inhibited by simultaneous addition of leptin, regardless of the presence or absence of the hormone mixture. These results suggest that stroma-derived factors intricately regulate mammary epithelial morphogenesis.  相似文献   
72.
Soft feces and a decreased delivery rate were observed in a specific-pathogen-free (SPF) C3H-scid mouse breeding colony. Grossly, the ceca were shrunken and edematous in the affected mice. Histopathologically, severe edema in the cecal submucosa as well as infiltration of inflammatory cells in the lamina propria and submucosa of the ceca and colon were observed. No pathogenic microorganisms were detected by the routine microbiological tests. By anaerobic bacterial-examination, Clostridium (C.) difficile with toxin A was isolated from the cecal contents of the affected mice. The mice were diagnosed with C. difficile-associated colitis. This case appears to be the first report of natural infection with C. difficile in SPF mice with clinical signs.  相似文献   
73.
In this study, we developed a novel multiplex polymerase chain reaction (PCR) method for simultaneous detection of up to eight events of genetically modified (GM) maize within a single reaction. The eight detection primer pairs designed to be construct specific for eight respective GM events (i.e., Bt11, Event176, GA21, MON810, MON863, NK603, T25, and TC1507) and a primer pair for an endogenous reference gene, ssIIb, were included in the nonaplex(9plex) PCR system, and its amplified products could be distinguished by agarose gel and capillary electrophoreses based on their different lengths. The optimal condition enabled us to reliably amplify two fragments corresponding to a construct specific sequence and a taxon specific ssIIb in each of the eight events of GM maize and all of nine fragments in a simulated GM mixture containing as little as 0.25% (w/w) each of eight events of GM maize. These results indicate that this multiplex PCR method could be an effective qualitative detection method for screening GM maize.  相似文献   
74.
A mandarin-type citrus fruit, ponkan (Citrus reticulata), was processed by in-line, chopper pulper, and hand-press extractions to investigate the effect of extraction method on the concentrations of bioactive compounds in processed juice. Concentrations of polymethoxylated flavones (tangeretin, nobiletin, and sinensetin) and beta-cryptoxanthin in juice, and inhibitory activities against arachidonate cyclooxygenase and lipoxygenases of the juice extract were analyzed. The juice processed by hand-press extraction contained the largest amounts of nobiletin (3.56 mg/100 mL), tangeretin (4.10 mg/100 mL), and sinensetin (0.13 mg/100 mL). Concentrations of beta-cryptoxanthin were 0.66, 0.59, 0.55, and 0.50 mg/100 mL in chopper pulper, in-line (5/64 in.), in-line (8/64 in.) and hand-press juices, respectively. Both extracts of in-line juices showed greater inhibitory activity toward platelet 12-lipoxygenase than the others. The inhibitory effect of hand-press juice extract on platelet cyclooxygenase activity was remarkable among juice extracts. All juice extracts effectively inhibited polymorphonuclear 5-lipoxygenase activity at nearly the same rate.  相似文献   
75.
Abstract

Aluminum-tolerant variants from cell cultures of carrot (Daucus carota L. cv. MS Yonsun) were selected by exposing them to excess ionic aluminum. The medium contained A1CI3 and 0.1 mM phosphate at pH 4.0. Under ionic aluminum stress (0.5-1.0 mM), 282 calli were selected. Twenty-eight fertile plants were regenerated from 7 selected calli. Based on the root elongation tests of the seedlings, the seeds displayed aluminum-tolerance. In the case of the cell line H7-08, the selection occurred at a frequency of ca. 6 × 10-7 when the materials were plated on agar medium containing 0.5 mM aluminum.  相似文献   
76.
Australian Burmese cats are predisposed to diabetes mellitus and, compared to other breeds, have delayed triglyceride clearance that may result in subtle changes within cells and tissues that trigger specific alterations in gene expression within peripheral blood leucocytes (PBLs). Expression of genes involved in energy metabolism (glucose-6-phosphate dehydrogenase and malate dehydrogenase), lipogenesis (ATP citrate lyase [ACL], fatty acid synthase [FAS] and sterol regulatory binding protein-1c [SREBP-1c]), and insulin signalling (insulin receptor substrates 1 and 2, and phosphatidylinositol-3 kinase), as well as cholesterol lipoprotein subfraction profiling were carried out on PBLs from lean Burmese cats and compared with similar profiles of age and gender matched lean and obese Australian domestic shorthaired cats (DSHs) in an attempt to identify possible biomarkers for assessing obesity.For the majority of the genes examined, the lean Burmese cats demonstrated similar PBL gene expression patterns as age and gender matched obese Australian DSH cats. Lean Burmese had increased expression of ACL and FAS, but not SREBP-1c, a main upstream regulator of lipid synthesis, suggesting possible aberrations in lipogenesis. Moreover, lean Burmese displayed a 3- to 4-fold increase in the very low density cholesterol fraction percentage, which was double that for obese DSH cats, indicating an increased degree of lipid dysregulation especially in relation to triglycerides. The findings suggest that Burmese cats may have a particular propensity for dysregulation in lipid metabolism.  相似文献   
77.
The aim of this study was to establish a method for estimating loading capacity for Japanese native horses by gait analysis using an accelerometer. Six mares of Japanese native horses were used. The acceleration of each horse was recorded during walking and trotting along a straight course at a sampling frequency of 200 Hz. Each horse performed 12 tests: one test with a loaded weight of 80 kg (First 80 kg) followed by 10 tests with random loaded weights between 85 kg and 130 kg and a final test with a loaded weight of 80 kg again. The time series of acceleration was subjected to fast Fourier transformation, and the autocorrelation coefficient was calculated. The first two peaks of the autocorrelation were defined as symmetry and regularity of the gait. At trot, symmetries in the 100, 110, and 125 kg tests were significantly lower than that in First 80 kg (P < 0.05, by analysis of covariance and Sidak's test). These results imply that the maximum permissible load weight is less than 100 kg, which is 29% of the body weight of Japanese native horses. Our method is a widely applicable and welfare‐friendly method for estimating maximum permissible load weights of horses.  相似文献   
78.
The Japanese sea cucumber Apostichopus japonicus has a pelagic-lecithotrophic larva. Here, we clarify larval dispersal among Japanese sea cucumber populations by describing the levels of distinctiveness and gene flow among red and green variant populations of A. japonicus across Toyama Bay using 11 polymorphic microsatellite markers. Samples of Japanese sea cucumber populations were collected from three localities (Noto, Shinminato, and Uozu) around Toyama Bay. Geographically separated populations of red and green variants were determined to be genetically distinct, supported by phylogenetic analysis and the distinctiveness range values of pairwise multilocus estimates of F ST. Contemporary migration analyses indicated that the majority of estimated migration events occurred within A. japonicus populations comprised of only either red or green variants. In a historical gene flow analysis, two best-fit models (n-island and stepping stone models) showed circulation for the gene migration in Toyama Bay among red variant populations. Our results provide useful information on the genetic structure of Japanese sea cucumber populations and will be helpful for genetic conservation and fisheries management of sea cucumber populations in Toyama Bay.  相似文献   
79.
Sequence variation of the mitochondrial DNA was analyzed to examine the genetic structure and demographic history of the goldlined spinefoot Siganus guttatus in the northwestern Pacific. In total, 451 nucleotide sequences spanning from the tRNAThr gene to the middle of the control region were determined from 254 specimens collected from five localities; three in the Ryukyu Islands (Okinawa, Miyako, and Ishigaki Islands), Taiwan, and Cebu Island of the Philippines; 73 variable sites and 75 haplotypes were detected. Our results showed restricted gene flow and genetic differentiation among all populations, with the exception of genetic homogeneity between the Miyako and Ishigaki populations; that is, this species will be able to cross between Miyako and Ishigaki (ca. 120 km) by the transport of pelagic larvae, and gene flow between Okinawa and Miyako/Ishigaki Islands (ca. 330–450 km) is restricted. A non-dispersal strategy will lead to restricted gene flow and genetic structuring in S. guttatus. Both the neutrality tests and the mismatch distribution indicated that S. guttatus might have been in populations at demographic equilibrium. This suggests that population range expansion may have been restricted owing to a non-dispersal strategy that may have restrained S. guttatus from demographic expansion after glaciation. The result will be of fundamental importance for resource management of this species.  相似文献   
80.
In the helix 25 region, 32 French Taylorella asinigenitalis isolates carried at least one 23S rRNA gene not containing intervening sequences (IVSs). No IVSs in the region were identified in three isolates and the other remaining 29 isolates carried one or more IVSs (UCD-1(T)IVS1A, UCD-1(T)IVS1B and UK-1IVS1B) described already and two new kinds of IVS (TaIVS1C and TaIVS1D). In the helix 45 region, no T. asinigenitalis isolates not carrying any IVSs were identified. UK-1IVS2B was identified in the region from 26 isolates. Five new kinds of IVSs (TaIVS2D, E, F, G and H) occurred in the region in the 13 isolates. Distinctly different tandem repeat units (RS48 and RS32 and RS-A, -B and -C) were evident in both regions, respectively, from the French (n=32) and American (n=3) T. asinigenitalis isolates. Thus, several different kinds of tandem repeat units and their combinations in IVSs in both regions within the gene were shown in 32 French isolates.  相似文献   
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