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γ‐Aminobutyrate (GABA) is commonly used as a food supplement and a health care product by young females, due to its positive roles in relieving stress, alleviating anxiety, and improving sleep. However, its recommended daily dose in different products varies widely. Besides, it is unknown whether, and how, GABA consumption during early pregnancy influences pregnancy establishment. In this study, we found that when pregnant mice were treated with a high (12.5 mg/g) dose of GABA (orally) during preimplantation, there was a reduction in the number of implantation sites on day 5 of pregnancy. Also, among these unimplanted embryos, most exhibited morphological degeneration and developmental retardation, and only a few of them developed into blastocysts but could not implant into the uterus. Moreover, the expression of uterine receptivity–related factors—LIF, E‐cadherin, and HOXA10—were all downregulated, while the number of uterine glands was reduced in the high GABA dose group. Finally, in vitro results demonstrated that GABA (ranging from 10 to 50 μg/μL) markedly inhibited preimplantation embryo development in a dose‐response manner. However, this inhibitory effect was not observed when the embryos were pretreated with 40 μΜ 2‐hydroxysaclofen, a GABAB antagonist, indicating that GABA exerts its inhibitory effects via its B‐type receptor. Our results suggest that exposure to certain GABA concentrations, during early pregnancy, can impair preimplantation embryo development via its B‐type receptor, and endometrial receptivity, which greatly disturbs early embryo implantation in mice. These findings could raise concerns about GABA consumption during the early stages of pregnancy.  相似文献   
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Abstract

Identifying the source effect on heavy metals to human health risk is essential for devising and implementing restoration policies for polluted soils. For this purpose, eight heavy metals (As, Cd, Hg, Cr, Cu, Ni, Pb, and Zn) in soil profile samples (0–10, 10–20, 20–30, and 30–40?cm) collected in the area around aluminum-plastic manufacturing facilities (APMF) were determined. An absolute principal component score multiple linear regression (APCS-MLR) model supported by a health risk assessment (HRA) model was developed to determine the source apportionment of soil heavy metals and contribution rate of pollution sources to human health risk. Results showed significant accumulations of eight metals in the topsoil (0–20?cm), parent material, transportation, APMF, and agricultural practices were the four major contributing sources for heavy metals in soils, with average contribution percentages of 21.69%, 24.99%, 29.60%, and 14.25%, respectively. Carcinogenic risk factors for adults (1.23E-04) and children (1.32E-04) were found to be above the acceptable level (1E-06 to 1E-04). The health risk quantification results indicated that parent material, APMF, transportation, agricultural practices, and unidentified factors accounted for 55.76%, 14.48%, 12.09%, 10.13%, and 7.54% of the carcinogenic risk for children and adults. The adverse impacts of Cd, Zn, and Pb accumulations in soil coming from APMF activities were significant and need to receive more attention.  相似文献   
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Li  H. X.  Liu  R. Q.  Zhang  H. M.  Cao  Z. X.  Zhu  L. X.  Li  Y. Y.  Ding  W. J.  Chen  Y. H.  Deng  Y. 《Russian Journal of Bioorganic Chemistry》2020,46(3):306-311
Russian Journal of Bioorganic Chemistry - AIDS/HIV is a serious life-threatening and public health problem that urges for new antiviral drugs to control. A bis-indole alkaloid voacamine has been...  相似文献   
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The marker strategy design (MSGD) has been proposed to assess and validate predictive markers for targeted therapies and immunotherapies. Under this design  相似文献   
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Wu  Yanping  Xu  Han  Cao  Xuefang  Liu  Rongrong  Tang  Li  Zeng  Zhonghua  Li  Weifen 《Probiotics and antimicrobial proteins》2020,12(2):649-656

Probiotics have always been considered as a supplementary therapy for many diseases especially gut disorders. The absorption and barrier function of the gut play a vital role in the maintenance of body homeostasis. This study was to investigate the protective effects of Bacillus amyloliquefaciens SC06 (Ba) on H2O2-induced oxidative stress on intestinal porcine epithelial cells (IPEC-1) based on the level of gene expression. We demonstrated that Ba was a safe probiotic strain in the first place. Results showed that treatment with H2O2 significantly increased the mRNA expression of absorptive transporters glucose transporter 2 (GLUT2), Ala/Ser/Cys/Thr transporter 1 (ASCT1), and ASCT2 compared with the control group. Meanwhile, oxidative stress induced a significant improvement in the mRNA expression of occludin (OCLN) and caspase-3, and remarkably inhibited the expression of L-type amino acid transporter 1 (LAT1) or B cell lymphoma-2 (Bcl-2), respectively. Pretreatment with Ba dramatically reversed the disturbance induced by oxidative stress on the mRNA expression of ASCT1, ASCT2, and OCLN, which also significantly prevented H2O2-inhibited LAT1 and Bcl-2 mRNA expression. However, Ba failed to exert any significant protective effect on GLUT2 and caspase-3 mRNA expression. We concluded that pretreatment with Ba could alleviate the damage caused by oxidative stress to a certain extent and conferred a protective effect to the intestine.

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Journal of Plant Research - Plant growth promoting rhizobacteria (PGPR) are a group of bacteria that promote plants growth in the rhizosphere. PGPRs are involved in various mechanisms that...  相似文献   
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