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581.
The local tissue-specific renin-angiotensin system (RAS) was identified. The aim of this study was to investigate the role of local bone RAS in the osteoporosis of aging mice. Twelve-month-old and two-month-old male mice were respectively assigned to the ageing and young groups. The tibias and femurs were collected for an analysis of histomorphology, bone mass, and gene and protein expression. H&E staining and micro-CT measurement showed a loss of the trabecular bone network and decrease of bone mineral density in the proximal tibial metaphysis of the aged mice. The PCR results indicated the significant up-regulation of renin and angiotensinogen (AGT) mRNA expression in both the tibia and femur of the ageing mice. Western blotting data showed that the tibial angiotensin II protein expression was significantly increased in the ageing group. The enhancement of renin and AGT expression in the bone tissue resulted in the increased production of angiotensin II which plays an important role in the pathology of age-related osteoporosis.  相似文献   
582.
Our results revealed that a 7-log reduction of Salmonella can be achieved by exposing fresh chicken litter for 80.5 to 100.8, 78.4 to 93.1, and 44.1 to 63 min at 70, 75, and 80°C, respectively, depending on initial moisture contents. However, the aged chicken litter requires more heat treatment.  相似文献   
583.
Female fertility declines dramatically over the age of 35 due to age‐related decreases in oocyte quality and quantity. Although mitochondrial transfer promises to be a technology that can improve the quality of such age‐impaired oocytes, the ideal mitochondrial donor remains elusive. In the present study, we aimed to identify whether aged adipose‐derived stem cells constitute an excellent mitochondrial donor that would improve the quality of aged mouse oocytes. We showed that aging significantly impaired the mitochondrial function in mouse oocytes, but did not significantly affect the mitochondrial function of adipose‐derived stem cells. However, the mitochondrial transfer from aged adipose‐derived stem cells did not mitigate the poor fertilization and embryonic development rates of aged oocytes.  相似文献   
584.
Cisplatin (CP) is a chemotherapeutic agent used to treat various types of cancer; nephrotoxicity is the most common adverse effect of the drug. We investigated the protective effects of propolis against CP induced kidney injury. Thirty-six male rats were divided into six equal groups: untreated control group, 50 mg/kg/day propolis group, 100 mg/kg/day propolis group, single-dose 7 mg/kg CP group, 7 mg/kg CP + 50 mg/kg/day propolis and 7 mg/kg CP + 100 mg/kg propolis. Rats were sacrificed after 14 days and kidneys were removed for histopathological and biochemical analyses. We used hematoxylin & eosin and periodic acid-Schiff staining to evaluate kidney histopathology and we used the TUNEL technique to assess apoptosis. We also measured total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), ischemia-modified albumin (IMA) and malondialdehyde (MDA) levels in tissue and blood specimens. Normal morphology was observed in the control, 50 mg/kg/day propolis and 100 mg/kg/day propolis groups by light microscopy. Degeneration of tubule cells, edema and tubule dilation were increased in the CP group compared to the control group. Degeneration of tubule cells and dilation of Bowman’s spaces were decreased in the CP + 50 mg/kg/day propolis and CP + 100 mg/kg/day propolis groups compared to the CP group. Tubule dilation decreased significantly in the CP + 100 mg/kg propolis group compared to the CP group. Also, the 7 mg/kg CP group exhibited altered proximal tubule epithelial cells, loss of brush border and thickening of the parietal layer of Bowman’s capsule in glomeruli and basal laminae of tubules. A normal brush border was observed in the CP + 50 mg/kg/day propolis and CP + 100 mg/kg/day groups. Serum OSI and MDA levels were increased in the CP group compared to the control group. Serum MDA levels decreased significantly in the CP + 50 mg/kg/day propolis and 100 mg/kg CP + propolis groups compared to the CP group. CP caused significant damage to kidney tissue; propolis exhibited dose-dependent prevention of tissue damage.  相似文献   
585.
586.
Glioblastomas (GBMs) are the most common of both benign and malignant primary brain tumours, in which the inflammatory and immunologic abnormalities are involved. Interleukin‐17A (IL‐17A) plays an important role in various inflammatory diseases and cancers. Several recent studies revealed that the expression of IL‐17A was overexpressed in human GBMs tissue. However, the accurate role of IL‐17A in GBMs remains unclear. In this study, we aimed to explore the effect of IL‐17A on cell migration and invasion of GBMs and the mechanism by which the effects occurred. We found that exogenous IL‐17A promoted significantly cell migration and invasion abilities in two GBMs cell lines (U87MG and U251) in a time‐dependent manner. In addition, the protein expressions of PI3K, Akt and MMP‐2/9 were increased in the GBMs cells challenged by IL‐17A. Furthermore, a tight junction protein ZO‐1 was down‐regulated but Twist and Bmi1 were up‐regulated. Treatment with a PI3K inhibitor (LY294002) significantly reduced the abilities of both migration and invasion in U87MG and U251 cells. LY294002 treatment also attenuated the IL‐17A causing increases of protein levels of PI3K, AKT, MMP‐2/9, Twist and the decreases of protein level of ZO‐1 in the U87MG and U251 cells. Taken together, we concluded that IL‐17A promotes the GBM cells migration and invasion via PI3K/AKT signalling pathway. IL‐17A and its related signalling pathways may be potential therapeutic targets for GBM.  相似文献   
587.
Early and late metestrus in the rat differ by progesterone levels. As it is known that progesterone shows a potential negative effect on cognitive performances and can counteract the estradiol-induced neural effects, we intended to study signaling proteins in the hippocampus, a structure representing a main brain area of cognitive function. Female OFA Sprague-Dawley rats were used in the studies and estrous phases were determined using vaginal smears. Hippocampal tissue was taken, proteins extracted, run on two-dimensional gel electrophoresis and proteins were identified by mass spectrometry methods (MALDI-TOF-TOF and nano-LC-ESI-MS/MS). Individual signaling protein levels quantified by specific software were shown to vary between the two phases, including NG,NG-dimethylarginine dimethylaminohydrolase 1 for nitric oxide signaling, guanine nucleotide-binding proteins, septin 6, septin 11, G-septin alpha, and 14-3-3 protein gamma. Results from this study indicate that early and late metestrus show differences in signaling pathways, that may help to design further investigations at the protein level and may assist to interpret literature on protein expression and brain protein levels in female rats. Moreover, signaling differences in hippocampus are challenging cognitive studies during these two metestrus phases probably revealing cognitive differences between early and late metestrus.  相似文献   
588.
Fan Z  Diao CH  Guo MJ  Du RJ  Song YF  Jing ZL  Yu M 《Carbohydrate research》2007,342(16):2500-2503
The weak inclusion complex of cyclomaltoheptaose (beta-cyclodextrin, betaCD) with p-nitrobenzoic acid was investigated in the solid state. Crystallography shows that two betaCD molecules co-crystallize with two p-nitrobenzoic acids and 28.5 water molecules [2(C(42)H(70)O(35))x2(C(7)H(5)NO(4))x28.5H(2)O] in the triclinic system.  相似文献   
589.
Zhang  Qiuhan  Li  Siliang  Lei  Ping  Li  Zixian  Chen  Feifei  Chen  Qi  Wang  Yulu  Gong  Jiami  Tang  Qi  Liu  Xinjin  Lan  Ke  Wu  Shuwen 《中国病毒学》2021,36(6):1387-1399
Virologica Sinica - Similar to that of other enteroviruses, the replication of enterovirus 71 (EV71) occurs on rearranged membranous structures called replication organelles (ROs)....  相似文献   
590.
Cadmium contamination in croplands is recognized one of the major threat, seriously affecting soil health and sustainable agriculture around the globe. Cd mobility in wastewater irrigated soils can be curtailed through eco-friendly and cost effective organic soil amendments (biochars) that eventually minimizes its translocation from soil to plant. This study explored the possible effects of various types of plants straw biochar as soil amendments on cadmium (Cd) phytoavailability in wastewater degraded soil and its subsequent accumulation in sunflower tissues. The studied biochars including rice straw (RS), wheat straw (WS), acacia (AC) and sugarcane bagasse (SB) to wastewater irrigated soil containing Cd. Sunflower plant was grown as a test plant and Cd accumulation was recorded in its tissues, antioxidant enzymatic activity chlorophyll contents, plant biomass, yield and soil properties (pH, NPK, OM and Soluble Cd) were also examined. Results revealed that addition of biochar significantly minimized Cd mobility in soil by 53.4%, 44%, 41% and 36% when RS, WS, AC and SB were added at 2% over control. Comparing the control soil, biochar amended soil effectively reduced Cd uptake via plants shoots by 71.7%, 60.6%, 59% and 36.6%, when RS, WS, AC and SB. Among all the biochar, rice husk induced biochar significantly reduced oxidative stress and reduced SOD, POD and CAT activity by 49%, 40.5% and 46.5% respectively over control. In addition, NPK were significantly increased among all the added biochars in soil–plant system as well as improved chlorophyll contents relative to non-bioachar amended soil. Thus, among all the amendments, rice husk and wheat straw biochar performed well and might be considered the suitable approach for sunflower growth in polluted soil.  相似文献   
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