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151.
Background aimsMesenchymal stromal cells and immunosuppressive factor IL-37 can both suppress concanavalin A (Con A)-induced hepatitis in mice. Endometrial regenerative cells (ERCs), novel types of mesenchymal-like stromal cells, possess powerful immunomodulatory effects and are effective in treating various diseases. The aim of this study was to explore the effects of ERCs in suppressing Con A-induced hepatitis and determine whether IL-37 overexpression could enhance the therapeutic effect of ERCs in this process.MethodsERCs were extracted from the menstrual blood of healthy female volunteer donors. The IL-37 gene was transferred into ERCs, and the expression of IL-37 in cells was detected by western blot and enzyme-linked immunosorbent assay. Hepatitis was induced by Con A in C57BL/6 mice that were randomly divided into groups treated with phosphate-buffered saline, ERCs, IL-37 or ERCs transfected with the IL-37 gene (IL-37-ERCs). Cell tracking, liver function, histopathological and immunohistological changes, immune cell proportions and levels of cytokines were measured 24 h after Con A administration.ResultsCompared with ERC or IL-37 treatment, IL-37-ERCs further reduced levels of liver enzymes (alanine aminotransferase and aspartate aminotransferase) and improved histopathological changes in the liver. In addition, IL-37-ERC treatment further reduced the proportions of M1 macrophages and CD4+ T cells and increased the proportion of regulatory T cells. Moreover, IL-37-ERC treatment resulted in lower levels of IL-12 and interferon gamma, and higher level of transforming growth factor beta.ConclusionsThe results of this study suggest that ERCs can effectively alleviate Con A-induced hepatitis. Furthermore, IL-37 overexpression can significantly enhance the therapeutic efficacy of ERCs by augmenting the immunomodulatory and anti-inflammatory properties of ERCs. This study may provide a promising strategy for treatment of T-cell-dependent hepatitis.  相似文献   
152.
Five new peptaibols, longibramides A–E ( 1 – 5 ) with 11 amino acid residues, were isolated from a fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, which was isolated from a mushroom Clitocybe nebularis (Batsch) P. Kumm collected from coniferous forest in the subboreal area of northeast China. The structures of longibramides A–E were determined by their spectroscopic data (NMR and MS-MS spectra), their absolute configurations were determined by X-ray diffractions and Marfey's analyses. The X-ray diffractions of longibramides A, B, and the similar CD spectra of A–E showed that they all had α-helix conformations. Longibramides B and E showed moderate cytotoxicities against BV2 and MCF-7 cells and also showed some inhibitory effects against methicillin-resistant Staphylococcus aureus MRSA T144. L-trans-Hyp was not commonly found in natural peptaibols, which was the 6th or 10th amino acid residue in longibramides C–E. The X-ray diffractions of longibramides A and B afforded the accuracy conformations of their secondary structures, which maybe help to interpret the structure-activity relationships of the family of peptaibols in the future.  相似文献   
153.
154.
Yue  Maofeng  Shen  Hao  Ye  Wanhui  Li  Weihua  Chen  Jinfeng 《Biological invasions》2021,23(9):2913-2925

Winter low temperature disturbance in the southern subtropics has important effects on the weed community structure, but the role of uniquely low temperatures in biological invasions is unclear. Here, we examined the competitive effects of an invasive plant, Bidens pilosa L., and its native congener, Bidens biternata (Lour.) Merr. et Sherff, during high and low temperature seasons to determine whether low temperatures promote the competitiveness of B. pilosa in the southern subtropics of China. The growth and physiological responses of the two Bidens species to low (10/5 °C) and optimum (30/25 °C) temperatures were examined to determine how the invasive B. pilosa responds to low temperature stress. Our results showed that the competitive balance index values of B. pilosa in low temperature seasons were significantly higher than those in high temperature seasons, which implied that low temperatures may be more beneficial to the competitiveness of B. pilosa than high temperatures in the southern subtropics. The smaller decline in the relative growth rate and the photosynthetic ability of B. pilosa compared with B. biternata under low temperature stress indicated that the former was less negatively affected by low temperature than the latter. A higher DPPH· (1.1-diphenyl-2-picrylhy-drazyl) scavenging rate and greater heat-stable protein content in B. pilosa under low temperatures might help the invasive plant to maintain more effective physiological functions and thus a higher growth rate. Overall, the uniquely low temperature in the southern subtropics of China is expected to promote the invasiveness of the exotic B. pilosa.

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155.
Oxidative stress negatively affects the in vitro maturation (IVM) of oocytes. Procyanidin B1 (PB1) is a natural polyphenolic compound that has antioxidant properties. In this study, we investigated the effect of PB1 supplementation during IVM of porcine oocytes. Treatment with 100 μM PB1 significantly increased the MII oocytes rate (p <0.05), the parthenogenetic (PA) blastocyst rate (p <0.01) and the total cell number in the PA blastocyst (p < 0.01) which were cultured in regular in vitro culture (IVC) medium. The PA blastocyst rate of regular MII oocytes activated and cultured in IVC medium supplemented with 100 and 150 μM PB1 significantly increased compared with control (p < 0.01 and p < 0.05). We also evaluated the reactive oxygen species (ROS) levels, mitochondrial membrane potential (Δψm) levels, glutathione (GSH) levels, and apoptotic levels in MII oocytes and cumulus cells following 100 μM PB1 treatment. The results showed that the PB1 supplementation decreased ROS production and apoptotic levels. In addition, PB1 was found to increase Δψm levels and GSH levels. In conclusion, PB1 inhibited apoptosis of oocytes and cumulus cells by reducing oxidative stress. Moreover, PB1 improved the quality of oocytes and promoted PA embryo development. Taken together, our results suggest that PB1 is a promising antioxidant additive for IVM of oocytes.  相似文献   
156.
157.
Spirochetes of the genus Treponema are surprisingly abundant in termite guts, where they play an important role in reductive acetogenesis. Although they occur in all termites investigated, their evolutionary origin is obscure. Here, we isolated the first representative of ‘termite gut treponemes’ from cockroaches, the closest relatives of termites. Phylogenomic analysis revealed that Breznakiella homolactica gen. nov. sp. nov. represents the most basal lineage of the highly diverse ‘termite cluster I', a deep-branching sister group of Treponemataceae (fam. ‘Termitinemataceae’) that was present already in the cockroach ancestor of termites and subsequently coevolved with its host. Breznakiella homolactica is obligately anaerobic and catalyses the homolactic fermentation of both hexoses and pentoses. Resting cells produced acetate in the presence of oxygen. Genome analysis revealed the presence of pyruvate oxidase and catalase, and a cryptic potential for the formation of acetate, ethanol, formate, CO2 and H2 - the fermentation products of termite gut isolates. Genes encoding key enzymes of reductive acetogenesis, however, are absent, confirming the hypothesis that the ancestral metabolism of the cluster was fermentative, and that the capacity for acetogenesis from H2 plus CO2 - the most intriguing property among termite gut treponemes - was acquired by lateral gene transfer.  相似文献   
158.
Gamma-Aminobutyric Acid Type B Receptor (GABABR) plays essential roles in tumor progression. However, the function of GABABR in colorectal cancer (CRC) needs further clarification. As the main part of GABABR, GABABR1 expression was identified significantly lower in tumor tissues than those in non-tumor normal tissues and that CRC patients with high GABABR1 expression lived longer. Further studies indicated that knockdown of GABABR1 elevated CRC cell proliferation, migration, and invasion. Furthermore, knockdown of GABABR1 activated the expression of the epithelial-mesenchymal transition (EMT)-related proteins N-cadherin and Vimentin, whereas decrease the protein level of E-cadherin. In addition, activation of Hippo/YAP1 signaling contributes to the GABABR1 down-regulation promoted proliferation, migration, invasion and EMT in CRC cells. At last, we verified the contribution of Hippo/YAP1 signaling in the GABABR1 down-regulation impaired biological phenotype of colon cancer cells in vivo. In summary, these data indicate that GABABR1 impairs the migration and invasion of CRC cells by inhibiting EMT and the Hippo/YAP1 pathway, suggesting that GABABR1 could be a potential therapeutic target for CRC.  相似文献   
159.
With the development of genomics, the update of modern imaging technology and the advent of artificial intelligence and big data, the surgical treatment of gastric cancer has gradually stepped into precision medicine. Precision surgery treatment of gastric cancer is based on accurate molecular typing and staging using modern molecular diagnostic technology and imaging, and the formulation of precise and individualized surgical treatment plans, with the concept of minimally invasive and accelerated rehabilitation surgery running through it. For intermediate-stage gastric cancer, we have adopted a comprehensive treatment approach including traditional radiotherapy and chemotherapy, targeted therapy and immunotherapy. Utilize artificial intelligence and big data technology to improve the standardization and interconnectivity of specialty data and realize the transformation of evidence-based medicine. Promoting the standardization, standardization and individualization of gastric cancer surgical treatment, providing patients with precise diagnosis and treatment, and further improving patients'' prognosis are the opportunities and challenges in the development of gastric cancer surgery.  相似文献   
160.
Lyme disease (LD) is one of the most important vector-borne diseases worldwide. However, there is limited information on the prevalence and risk analysis using correlated factors in the tropical areas. A total of 1583 serum samples, collected from five hospitals of Hainan Province, were tested by immunofluorescence assay (IFA) and western blot (WB) analyses using anti-Borrelia burgdorferi antibodies. Then, we mapped the distribution of positive rate (by IFA) and the spread of confirmed Lyme patients (by WB). Using ArcGIS, we compiled host-vector-human interactions and correlated data as risk factor layers to predict LD risk in Hainan Province. There are three LD hotspots, designated hotspot I, which is located in central Hainan, hotspot II, which contains Sanya district, and hotspot III, which lies in the Haikou-Qiongshan area. The positive rate (16.67% by IFA) of LD in Qiongzhong, located in hotspot I, was higher than that in four other areas. Of confirmed cases of LD, 80.77% of patients (42/52) whose results had been confirmed by WB were in hotspots I and III. Hotspot II, with unknowed prevalence of LD, need to be paid more attention considering human-vector interaction. Wuzhi and Limu mountains might be the most important areas for the prevalence of LD, as the severe host-vector and human-vector interactions lead to a potential origin site for LD. Qiongzhong is the riskiest area and is located to the east of Wuzhi Mountain. In the Sanya and Haikou-Qiongshan area, intervening in the human-vector interaction would help control the prevalence of LD.  相似文献   
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