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231.
The aim of this study is to examine 1) muscle fiber type composition, 2) myofiber diameter, and 3) aquaporin (AQP) 7 and AQP 9 mRNA expressions by quantitative PCR in muscles of obese db/db mice. The myofiber type composition of skeletal muscle was not statistically significantly different between db/db mice and control mice; while the average myofiber diameter ratio showed a decrease in db/db mice. The expression of AQP7 but not AQP9 mRNA in the skeletal and cardiac muscles was significantly upregulated in db/db mice. Thus this study revealed quantitatively that type 2 myofiber atrophy was shown in the skeletal muscles of db/db mice. AQP7 mRNA expression was upregulated in the skeletal and cardiac muscles of db/db mice.  相似文献   
232.
Classical swine fever (CSF) caused by CSF virus (CSFV) is a highly contagious disease of pigs. The viral protein Npro of CSFV interferes with alpha- and beta-interferon (IFN-α/β) induction by promoting the degradation of interferon regulatory factor 3 (IRF3). During the establishment of the live attenuated CSF vaccine strain GPE-, Npro acquired a mutation that abolished its capacity to bind and degrade IRF3, rendering it unable to prevent IFN-α/β induction. In a previous study, we showed that the GPE- vaccine virus became pathogenic after forced serial passages in pigs, which was attributed to the amino acid substitutions T830A in the viral proteins E2 and V2475A and A2563V in NS4B. Interestingly, during the re-adaptation of the GPE- vaccine virus in pigs, the IRF3-degrading function of Npro was not recovered. Therefore, we examined whether restoring the ability of Npro to block IFN-α/β induction of both the avirulent and moderately virulent GPE--derived virus would enhance pathogenicity in pigs. Viruses carrying the N136D substitution in Npro regained the ability to degrade IRF3 and suppress IFN-α/β induction in vitro. In pigs, functional Npro significantly reduced the local IFN-α mRNA expression in lymphoid organs while it increased quantities of IFN-α/β in the circulation, and enhanced pathogenicity of the moderately virulent virus. In conclusion, the present study demonstrates that functional Npro influences the innate immune response at local sites of virus replication in pigs and contributes to pathogenicity of CSFV in synergy with viral replication.  相似文献   
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234.

Pepsin-solubilized collagen (PSC) was prepared from the dermis of sea cucumber Apostichopus japonicus (green type) by performing pepsin digestion to collagen fiber pretreated with disaggregating solution (0.1 M Tris–HCl, pH 8.0, containing 0.5 M NaCl, 0.05 M ethylenediaminetetraacetic acid (EDTA), and 0.2 M 2-mercaptoethanol) and 0.1 M NaOH. On sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE), the PSC clearly showed two alpha bands under phosphate buffer system in the presence of 3.5 M urea. An antiserum was raised against chromatographically purified major molecular species in the PSC, and immunoblot analyses were performed for the soluble fractions at 4 M guanidine hydrochloride treatment and disaggregation as well as the collagen fiber before and after treatment. These fractions and collagen fibers showed quite similar band patterns to that of the PSC, showing mainly two alpha bands. These combined results suggest that the major molecular species of collagen contains at least two distinct alpha components and that the effect of pepsin digestion is relatively small on the structure of this collagen type.

  相似文献   
235.
Journal of General Plant Pathology - Wheat resistance genes Rwt3 and Rwt4 constitute a host-specificity barrier against non-wheat pathotypes of the blast fungus, Pyricularia oryzae. To understand...  相似文献   
236.
Four female Shiba goats were used to determine the influence of body weight loss by dietary restriction on estrous cyclicity. The dietary restriction was started on the day following ovulation. The goats were fed hay cube and straw at an amount of 30% of energy requirement based on weekly body weight measurement. The ovaries were monitored daily by transrectal ultrasonography and blood samples were collected daily by jugular venipuncture for ovarian steroids analysis. After the start of food restriction, all animals lost body weight and entered ovarian quiescence. Intervals to the onset of ovarian quiescence tended to depend on the body weight of each animal at the start of food restriction. The mean concentration of progesterone during the mid-luteal phase (from 7 to 13 days after ovulation) in the last estrous cycle before ovarian quiescence was significantly lower than that in normal estrous cycle of the control period (19.7 +/- 2.8 vs 12.3 +/- 2.2 ng/ml, P<0.05), whereas there was no significant difference in the length of the luteal phase, determined as the period when corpora lutea existed and concentrations of progesterone were equal to or greater than 1 ng/ml (15.8 +/- 1.5 vs 15.0 +/- 2.8 days, P>0.1). A rise of estradiol concentration and follicular growth in the follicular phase following a decline of progesterone level after luteal regression tended to be suppressed at the onset of ovarian quiescence. It seems that the present results are consistent with previous findings that nutritionally induced body weight loss influences the secretion of ovarian steroids and eventually induces ovarian quiescence.  相似文献   
237.
The N'-benzoyl group of N-tert-butyl-N'-benzoyl-3,5-dimethylbenzohydrazide (1) was converted to a series of benzoheterocyclecarbonyl groups in order to investigate the potential usefulness of superimposing a hydrazine insecticide on 20-hydroxyecdysone. A series of analogues with benzodioxole, benzodioxane, benzodioxapine, indole, benzoxazole, benzoxazine or benzothiazole instead of the phenyl group of (1) were synthesized and tested for their insecticidal activity against the common cutworm (Spodoptera litura F). N-tert-Butyl-N'-(3,5-dimethylbenzoyl)-1,3-benzodioxole-5-carbohydrazide and N-tert-butyl-N'-(3,5-dimethylbenzoyl)-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide showed high insecticidal activities, superior to that of (1) and equal to that of the commercial insecticide tebufenozide (RH-5992).  相似文献   
238.
A series of N'-benzoheterocyclecarbonyl-N-tert-butyl-3,5-dimethylbenzohydrazide analogues possessing a variety of substituents on the benzene rings of the benzoheterocyle moieties were synthesized and tested for their insecticidal activity. The introduction of a methyl group at the R1 position of the benzoheterocycle moiety strongly increased the insecticidal activity. Among the analogues synthesized, N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-6-chromanecarbohydrazide showed the highest insecticidal activity (LC50 = 0.89 mg litre(-1)).  相似文献   
239.
Distribution of ASCT1, a neutral amino acid transporter, in non-neuronal peripheral tissues of adult and developing mice was examined by immunohistochemistry and immunoelectron microscopy. Immunoreactivity for ASCT1 in the digestive system was localized in basal cells of stratified squamous epithelia from oral parietes to nonglandular region of the stomach, chief cells of the glandular stomach, acinar cells of the salivary gland and exocrine pancreas, and Paneth's cells of the small intestine, in all of which the basolateral membrane was selectively immuno-labeled. In the liver of adult mice, ASCT1 immunoreactivity was detected on the plasma membrane of hepatocytes surrounding central veins, and a temporal expansion of immunoreactive hepatocytes was observed in the embryonic and CCl4-treated adult livers. ASCT1 was also localized on the plasma membranes of proximal uriniferous tubule epithelial cells in the kidney of adult mice, and those of supporting cells in the medulla of adrenal gland. These results suggest that ASCT1 is expressed in various non-neuronal peripheral tissues in mice, and it contributes to the amino acid transport throughout non-neuronal tissues.  相似文献   
240.
Pestiviruses can be distinguished as two biotypes, cytopathogenic (cp) and noncytopathogenic (noncp), by the morphological changes that they induce during growth in cultured cells. In this study, the cp phenotype of several classical swine fever viruses (CSFV) was evaluated by the detections of the nonstructural proteins NS2-3 and NS3 using immunoprecipitation and Western blotting in different porcine cell lines. Most CSFVs that showed the exaltation of Newcastle disease virus (END) phenomenon (END(+) viruses) did not induce cytopathic effect (CPE) in any cell line, and detections of NS2-3 and NS3 showed a strong signal for NS2-3 in the END(+) virus-infected cells. However, clear CPE was observed in serum-free cultured cells (FS-L3 and CPK-NS) infected with viruses that induce intrinsic interference but did not show the END phenomenon (END(-) viruses), and signal of NS3 was strongly detected than that of NS2-3 in these cells at 72 hr after infection. As the results of the analysis of FS-L3 cells infected with ALD (END(+) virus) and ALD-END(-) virus (END(-) virus) at several incubations, the signal of NS3 detected was strengthened with CPE that become evident progressively. These results suggest that CPE is associated with the accumulation of NS3, which is promoted in serum-free cell lines infected with END(-) viruses. Thus, indicating there is a close relationship between CPE and the quantity of NS3 produced in END(-) CSFV infection.  相似文献   
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