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71.
Properties of macrophages and lymphocytes appearing in renal fibrosis remains to be investigated. F344 rats were injected once a week with cisplatin (2 mg/kg body weight) for 8 weeks and examined at post-final injection weeks 1, 3, 6, 9, and 12. Rats developed progressive renal fibrosis at weeks 1 to 6 as fibrosis-progress phase, and subsequent amelioration at weeks 9 and 12. CD68+ M1-macrophages and major histocompatibility complex (MHC) class II+ macrophages remarkably increased persistently, whereas CD163+ M2-macrophages slightly increased. MHC class II+/CD68+ and MHC class II+/CD163+ macrophages were present, indicating that MHC class II+ macrophages might have both functions of M1- and M2-macrophages. In the fibrosis-progress phase, interleukin (IL)-6, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ for M1-factors, and transforming growth factor (TGF)-β1 and IL-10 for M2-factors tended to increase; tissue injury by M1 and fibrosis by M2 might have occurred simultaneously. Lots of CD4+ and CD8+ T cells appeared in close relation with MHC class II+ macrophages, and mainly CD4+ T cells formed aggregations. In the lymphocyte aggregates collected by laser microdissection, expression of IL-17A (for Th17 cells) and forkhead box P3 (FoxP3) (for Treg) significantly increased at weeks 1 and 6, respectively; presumably, Th17 cells might be involved in tissue injury, whereas Treg might be related to fibrosis amelioration. These results suggested that macrophages and T cells may contribute interrelatedly to renal fibrosis.  相似文献   
72.
Caffeic acid derivatives in the roots of yacon (Smallanthus sonchifolius)   总被引:2,自引:0,他引:2  
Five caffeic acid derivatives were found in the roots of yacon, Smallanthus sonchifolius (Poepp. and Endl.) H. Robinson, Asteraceae, as the major water-soluble phenolic compounds. The structures of these compounds were determined by analysis of spectroscopic data. Two of these were chlorogenic acid (3-caffeoylquinic acid) and 3,5-dicaffeoylquinic acid, common phenolic compounds in plants of the family Asteraceae. Three were esters of caffeic acid with the hydroxy groups of aldaric acid, derived from hexose. The structure of the aldaric moiety was determined by hydrolysis and comparison of NMR spectra with those of standard aldaric acids. The compounds were novel caffeic acid esters of altraric acid: 2,4- or 3,5-dicaffeoylaltraric acid, 2,5-dicaffeoylaltraric acid, and 2,3,5- or 2,4,5-tricaffeoylaltraric acid.  相似文献   
73.
74.
Wild relatives genetically close to cultivars are precious genetic resources for plant breeding. Oryza rufipogon, O. barthii, O. glumaepatula, O. meridionalis and O. longistaminata are such wild species, and are also categorized as AA genome species based on their structural similarities. Chromosome segment substitution lines (CSSLs) are a powerful resource in breeding and genetics, and numerous rice CSSLs have been produced. This study aimed to develop DNA markers for evaluation of CSSLs directly by PCR and subsequent gel electrophoresis. We confirmed that up to 155 of 188 markers developed for detection of japonica-indica INDELs could also detect INDELs between rice cultivars and wild AA-species accessions. Percentages of applicable markers were higher in O. rufipogon accessions (61.7 to 85.6%), and lower in accessions of other four AA species (39.8 to 51.4%). These markers were distributed throughout the rice chromosomes, and will be useful for genotyping of CSSLs and other genetic resources derived from crosses between rice cultivars and closely related wild species.  相似文献   
75.
Four prenylated flavanones were isolated from the methanol extract of the flowers of Azadirachta indica (the neem tree) as potent antimutagens against Trp-P-1 (3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole) in the Salmonella typhimurium TA98 assay by activity-guided fractionation. Spectroscopic properties revealed that those compounds were 5,7,4'-trihydroxy-8-prenylflavanone (1), 5,4'-dihydroxy-7-methoxy-8-prenylflavanone (2), 5,7,4'-trihydroxy-3',8-diprenylflavanone (3), and 5,7,4'-trihydroxy-3',5'-diprenylflavanone (4). All isolated compounds were found for the first time in this plant. The antimutagenic IC(50) values of compounds 1-4 were 2.7 +/- 0.1, 3.7 +/- 0.1, 11.1 +/- 0.1, and 18.6 +/- 0.1 microM in the preincubation mixture, respectively. These compounds also similarly inhibited the mutagenicity of Trp-P-2 (3-amino-1-methyl-5H-pyrido[4,3-b]indole) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine). All of the compounds 1-4 strongly inhibited ethoxyresorufin O-dealkylation activity of cytochrome P450 1A isoforms, which catalyze N-hydroxylation of heterocyclic amines. However, compounds 1-4 did not show significant inhibition against the direct-acting mutagen NaN(3). Thus, the antimutagenic effect of compounds 1-4 would be mainly based on the inhibition of the enzymatic activation of heterocyclic amines.  相似文献   
76.
Quantitative real-time polymerase chain reaction (qRT-PCR) analysis was conducted to determine whether or not there are interstrain or site-dependent differences in the gene expression profiles of skeletal muscles in SJL/J and A/J mice as dysferlinopathy models. Upon analysis by qRT-PCR, SJL/J mice showed a trend of increased gene expression level of uncoupling protein 2 in the rectus femoris and longissimus lumborum at 30 weeks of age when dystrophic lesions became histopathologically pronounced. Heme oxygenase 1 and S100 calcium binding protein A4 were upregulated in the rectus femoris, longissimus lumborum and abdominal muscles, in which dystrophic lesions occur more commonly in SJL mice. The gene expression levels of heat shock protein 70 in most muscles of A/J mice were lower than those of BALB/c mice as control. SJL/J mice exhibited a marked lowering of decay-accelerating factor 1/CD55 gene expression level in all studied muscles except for the heart at all ages compared with that of BALB/c mice. This study showed that there were some interstrain differences in the gene expres sion profiles of skeletal muscles between SJL/J and A/J mice. Further investigation is required to reveal whether these alterations of the expression levels are the cause of dystrophic changes or occur subsequent to muscle damage.  相似文献   
77.
Effects of exposure to hot environment on urea metabolism were studied in lactating Holstein cows. Four cows were fed ad libitum a total mixed ration and housed in a temperature‐controlled chamber at constant moderate (18°C) or high (28°C) ambient temperatures in a cross‐over design. Urea nitrogen (N) kinetics was measured by determining urea isotopomer in urine after single injection of [15N2]urea into the jugular vein. Both dry matter intake and milk yield were decreased under high ambient temperature. Intakes of total N and digestible N were decreased under high ambient temperature but urinary urea‐N excretion was increased. The ratio of urea‐N production to digestible N was increased, whereas the proportion of gut urea‐N entry to urea‐N production tended to be decreased under high ambient temperature. Neither return to the ornithine cycle, anabolic use nor fecal excretion of urea‐N recycled to the gut was affected by ambient temperature. Under high ambient temperature, renal clearance of plasma urea was not affected but the gut clearance was decreased. Increase of urea‐N production and reduction of gut urea‐N entry, in relative terms, were associated with increased urinary urea‐N excretion of lactating dairy cows in higher thermal environments.  相似文献   
78.
We investigated the effect of heat stress on Ca, P and Mg balance and bone turnover in lactating cows. In a 2 × 2 crossover design, four multiparous lactating Holstein cows were kept in a chamber and subjected to a constant moderate (18°C) ambient temperature (MT) or high (28°C) ambient temperature (HT). The cows were fed total mixed ration (Ca, 0.7%; P, 0.4%; Mg, 0.2%) ad libitum. The milk yield under HT (35.4 kg/day) tended to be lower (P < 0.10) than that under MT (43.2 kg/day). The concentrations of milk P (P < 0.05) and Mg (P < 0.01) were significantly lower under HT than MT. The Ca, P and Mg intake (P < 0.10); Ca (P < 0.10), P, and Mg (P < 0.05) secretion into milk; and Ca (P < 0.05), P (P < 0.01), and Mg (P < 0.05) absorption in the intestine were lower under HT than MT. The plasma osteocalcin, a marker of bone turnover, was significantly lower (P < 0.05) under HT than MT. Heat stress did not affect plasma C‐telopeptide of collagen type I, a bone resorption marker, and plasma parathyroid hormone concentration.  相似文献   
79.
Tropical Animal Health and Production - Browse species are important sources of forage for livestock in Ethiopia, especially during the dry season, when the quality and quantity of green herbage is...  相似文献   
80.
Optimization of the solid-phase extraction cleanup procedure enabled the GC-MS analysis of acrylamide in tea samples without the interference of bromination by tea catechins. Although polyvinylpolypyrrolidone (PVPP) is available for removing tea catechins from tea extract, the peaks derived from PVPP had the same retention time as brominated acrylamide in mass chromatograms obtained by GC-MS. A considerable amount of acrylamide was formed at roasting temperatures of > or =120 degrees C; the highest acrylamide level was observed when tea samples were roasted at 180 degrees C for 10 min. Higher temperatures and longer processing times caused a decrease in the acrylamide content. Furthermore, an analysis of 82 tea samples showed that rather than the reducing sugar content, the asparagine content in tea leaves was a significant factor related to acrylamide formation in roasted products. The acrylamide level in roasted tea products was controlled by asparagine in the presence of reducing sugars.  相似文献   
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