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Ex vivo expanded decidua-basalis(DB)-derived mesenchymal stem cells (MSCs) obtained from single donors have demonstrated therapeutic benefits in in vitro and in vivo studies. In this report, the intravenous and subcutaneous administration of DB-MSCs obtained from five healthy donors was assessed considering clinical grade proliferation, accessibility, and toxic effects in Wistar albino rats. The ability of the obtained DB-MSCs for differentiating, as well as their expression of several cell surface markers and immunomodulatory activities, were all assessed. Clinical standard proliferated cells were administered to animals intravenously and subcutaneously in a series of preclinical models in order to assess their in vivo toxicity, general safety, and tumorigenic possibilities. We established that DB cells exhibit structural and functional traits with MSCs. At various doses supplied intravenously or subcutaneously, the research showed no fatality, abnormal response to therapy, or substantial pathological modifications in the rats. Furthermore, there was no indication of prenatal damage in the same animal species when the rats were repeatedly treated with DBMSCs. Thus, DBMSCs were demonstrated to be non-toxic, non-teratogenic, and non-tumorigenic. To determine whether they can be administrated to human patients without risk, more investigation is recommended.  相似文献   
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The rise and expansion of Tibetan Empire in the 7th to 9th centuries AD affected the course of history across East Eurasia, but the genetic impact of Tibetans on surrounding populations remains undefined. We sequenced 60 genomes for four populations from Pakistan and Tajikistan to explore their demographic history. We showed that the genomes of Balti people from Baltistan comprised 22.6–26% Tibetan ancestry. We inferred a single admixture event and dated it to about 39–21 generations ago, a period that postdated the conquest of Baltistan by the ancient Tibetan Empire. The analyses of mitochondrial DNA, Y, and X chromosome data indicated that both ancient Tibetan males and females were involved in the male-biased dispersal. Given the fact that the Balti people adopted Tibetan language and culture in history, our study suggested the impact of Tibetan Empire on Baltistan involved dominant cultural and minor demic diffusion.  相似文献   
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Abstract

The modular structure of bacterial ribonuclease P (RNase P) ribozymes, which recognize tertiary structures of precursor tRNAs (pre-tRNAs) to cleave their 5′ leader sequence, can be dissected physically into the two structured domain RNAs (S-domain and C-domain). Separately prepared S-domain RNA and C-domain RNA assemble to form bimolecular forms of RNase P ribozymes. We analyzed the effects of polyethylene glycols (PEGs) on pre-tRNA cleavage catalyzed by bimolecular RNase P ribozymes to examine the effects of molecular crowding on the reaction. PEG molecular crowders significantly enhanced the activities of bimolecular RNase P ribozymes, some of which were hardly active without PEGs.  相似文献   
135.
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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Of 24 fungi belonging to more than five genera isolated from tubers of rotten Helianthus tuberosus, 11-inulinolytic active isolates were able to develop halo zones around their fungal colonies, indicating inulinase activity. Alternaria, Aspergillus, Fusarium, Pencillium and Trichoderma were the most common inulinolytic genera, representing more than 90?% of the total positive inulinolytic fungi. Aspergillus tamarii and Pencillium citrinum quantitatively recorded better growth (5.5 and 4.7?mg?ml?1) and inulinase production (21.53 and 20.15?U?ml?1) in submerged culture. The enzyme preparation showed also invertase activity. Aspergillus tamarii, as the most potent producer of inulinase, was identified using the Inter Transcribed Spacer marker. The sequence comparisons showed that our molecularly identified strain (GU295949) is related more closely to A. tamarii strains of the gene bank. Statistical screening using the fractional factorial Plackett-Burman design with 12 run was applied for screening ten variables, the low levels of pH (4.8), inoculum size (103 spore?g?1), NH4NO3 (1.0?mg?g?1) and MgSO4 (0.12?mg?g?1), were the most significant variables on A. tamarii inulinase production. The high inulinase/invertase ratio (1.841?C4.293) classified the enzyme preparation as inulinases, which can be used efficiently in production of fructose syrup from tubers of H. tuberosus.  相似文献   
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140.
Effects of angiotensin II and captopril on rewarding properties of morphine   总被引:1,自引:0,他引:1  
The effects of captopril and Ang II on morphine-induced conditioned place preference (CPP) and morphine self-administration in male Wistar rat were investigated. In CPP experiment, injection of captopril before test significantly decreased the difference of the time spent in compartment A between pre- and post-conditioning compared to morphine group. In self- administration experiment number of active lever pressing was significantly greater than passive in morphine group. In captopril group number of active lever pressing was significantly lower than morphine group however, there was not significant difference between active and passive lever pressed number. The results showed that captopril significantly decreased morphine-induced conditional place preference and morphine self-administration but the effect of Ang II was not significant. It can be concluded that RAS may have a role in rewarding properties of morphine.  相似文献   
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