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991.
As one of the adjuvant treatments for cancer treatment, traditional Chinese medicine treatment has a wide range of cancer treatments, such as preventingmetastasis and relapse, improving the efficacy of radiotherapy and chemotherapy,reducing the side effects of chemotherapy, improving body function, extendinglife and improving the life quality. Geniposide (GEN) is a bioactive substanceextracted from the fruit of gardenia. In recent years, it has attracted attentiondue to its anti-tumor effect. In this study, we aimed to investigate whetherGEN could inhibit the proliferation of human breast cancer cells (MCF-7) andpromote its apoptosis. The half-inhibitory concentration (IC50) values of GENwere firstly determined as 16.06, 14.85 and 13.14 mg/mL by the CCK-8 experiment after cells treated for 24 h, 48 h, and 72 h, respectively. The inhibitory effectof GEN on MCF-7 cells was in concentration- and time-dependent manners fromthe results of CCK-8 experiment and Live/Dead staining. AO/EB staining resulthas shown that GEN has induced MCF-7 cell apoptosis.  相似文献   
992.
Lu  Shan  Fan  Xingyu  Liu  Sijian  Liu  Xiaoyu  Wang  Lizhen 《中国科学:生命科学英文版》2020,63(4):592-598
Retinal injury is the most common ocular impairment associated with shaken baby syndrome(SBS), which could lead to vision loss and blindness. However, a woodpecker does not develop retinal hemorrhages or detachment even at a high acceleration of 1,000×g during pecking. To understand the mechanism of retinal injury and its resistance strategy, we put insight into the special ability of the woodpecker to protect the retina against damage under acceleration–deceleration impact. In this study, the structural and mechanical differences on the eyes of the woodpecker and human were analyzed quantitatively based on anatomical observation. We developed finite element eye models of the woodpecker and human to evaluate the dynamic response of the retina to the shaking load obtained from experimental data. Moreover, several structural parameters and mechanical conditions were exchanged between the woodpecker and human to evaluate their effects on retinal injury in SBS. The simulation results indicated that scleral ossification, lack of vitreoretinal attachment, and rotational acceleration–deceleration impact loading in a woodpecker contribute to the resistance to retinal injuries during pecking. The above mentioned special physical structures and mechanical behavior can distribute the high strain in the posterior segment of the woodpecker's retina, which decrease the risk of retinal injury to SBS.  相似文献   
993.
This paper examines caregiving for sick older family members in the context of socio-economic transformations in rural China, combining empirical investigation with normative inquiry. The empirical part of this paper is based on a case study, taken from fieldwork in a rural Chinese hospital, of a son who took care of his hospitalized mother. This empirical study highlighted family members’ weiqu (sense of unfairness)—a mental status from experiencing mistreatment and oppression in family care, yet with constrained power to explicitly protest or make care-related choices. Underpinning people’s weiqu and constrained choice, as informed by the conception of structural injustice, is the impact of unjust social structures, organized by unfavourable norms, discriminatory social policies and institutions targeting rural populations. By restraining individual choices and capacities in supporting health care for aging populations, these unjust structures create additional difficulties for and discriminations against rural families and their older members. Some policy recommendations are proposed to mitigate structural injustice so as to empower families and promote care for older people in rural settings.  相似文献   
994.
Tubulointerstitial fibrosis is the ultimate common pathway of all manners of chronic kidney disease. We previously demonstrated that specific deletion of Numb in proximal tubular cells (PTCs) prevented G2/M arrest and attenuated renal fibrosis. However, how Numb modulates cell cycle arrest remains unclear. Here, we showed that Numb overexpression significantly increased the protein level of hypoxia-inducible factor-1α (HIF-1α). Numb overexpression-induced G2/M arrest was blocked by silencing endogenous HIF-1α, subsequently downregulated the expression of cyclin G1 which is an atypical cyclin to promote G2/M arrest of PTCs. Further analysis revealed that Numb-augmented HIF-1α protein was blocked by simultaneously overexpressing MDM2. Moreover, silencing Numb decreased TGF-β1-induceded HIF-1α protein expression. While endogenous MDM2 was knocked down this reduction was reversed, indicating that Numb stabilized HIF-1α protein via interfering MDM2-mediated HIF-1α protein degradation. Interestingly, HIF-1α overexpression significantly upregulated the expression of Numb and silencing endogenous HIF-1α blocked CoCl2 or TGF-β1-induced Numb expression. Chromatin immunoprecipitation (ChIP) assays demonstrated that HIF-1α binded to the promoter region of Numb. This binding was significantly increased by TGF-β1. Collectively, these data indicate that Numb and HIF-1α cooperates to promote G2/M arrest of PTCs, and thus aggravates tubulointerstitial fibrosis. Numb might be a potential target for the therapy of tubulointerstitial fibrosis.  相似文献   
995.
Ovarian cancer (OV) is the most common gynaecological cancer worldwide. Immunotherapy has recently been proven to be an effective treatment strategy. The work here attempts to produce a prognostic immune-related gene pair (IRGP) signature to estimate OV patient survival. The Gene Expression Omnibus (GEO) and Cancer Genome Atlas (TCGA) databases provided the genetic expression profiles and clinical data of OV patients. Based on the InnateDB database and the least absolute shrinkage and selection operator (LASSO) regression model, we first identified a 17-IRGP signature associated with survival. The average area under the curve (AUC) values of the training, validation, and all TCGA sets were 0.869, 0.712, and 0.778, respectively. The 17-IRGP signature noticeably split patients into high- and low-risk groups with different prognostic outcomes. As suggested by a functional study, some biological pathways, including the Toll-like receptor and chemokine signalling pathways, were significantly negatively correlated with risk scores; however, pathways such as the p53 and apoptosis signalling pathways had a positive correlation. Moreover, tumour stage III, IV, grade G1/G2, and G3/G4 samples had significant differences in risk scores. In conclusion, an effective 17-IRGP signature was produced to predict prognostic outcomes in OV, providing new insights into immunological biomarkers.  相似文献   
996.
The bacterial genus Dietzia is widely distributed in various environments. The genomes of 26 diverse strains of Dietzia, including almost all the type strains, were analysed in this study. This analysis revealed a lipid metabolism gene richness, which could explain the ability of Dietzia to live in oil related environments. The pan-genome consists of 83,976 genes assigned into 10,327 gene families, 792 of which are shared by all the genomes of Dietzia. Mathematical extrapolation of the data suggests that the Dietzia pan-genome is open. Both gene duplication and gene loss contributed to the open pan-genome, while horizontal gene transfer was limited. Dietzia strains primarily gained their diverse metabolic capacity through more ancient gene duplications. Phylogenetic analysis of Dietzia isolated from aquatic and terrestrial environments showed two distinct clades from the same ancestor. The genome sizes of Dietzia strains from aquatic environments were significantly larger than those from terrestrial environments, which was mainly due to the occurrence of more gene loss events during the evolutionary progress of the strains from terrestrial environments. The evolutionary history of Dietzia was tightly coupled to environmental conditions, and iron concentrations should be one of the key factors shaping the genomes of the Dietzia lineages.  相似文献   
997.
Follistain-like protein 1 (FSTL1), has been recently demonstrated to be involved in the embryo development of nervous system and glioblastoma. However, the role of FSTL1 in neuroinflammation remains unexplored. In this study, the expression of FSTL1 in astrocytes was verified and its role was studied in neuroinflammation induced by in vivo intracerebroventricular (ICV) injection of lipopolysaccharide (LPS) or LPS treatment to astrocytes in vitro. FSTL1 was significantly induced after ICV LPS injection or LPS treatment. FSTL1 suppressed upregulation of pro-inflammatory cytokines in astrocytes after LPS treatment. Moreover, FSTL1 downregulated expression of pro-inflammatory cytokines through suppressing MAPK/p-ERK1/2 pathway in astrocytes. Our results suggest that FSTL1 may play an anti-inflammatory role in neuroinflammation mediated by astrocytes.  相似文献   
998.
An alcohol dehydrogenase from Candida parapsilosis CCTCC M203011 was characterized along with its biochemical activity and structural gene. The amino acid sequence shows similarity to those of the short-chain dehydrogenase/reductases but no overall identity to known proteins. This enzyme with unusual stereospecificity catalyzes an anti-Prelog reduction of 2-hydroxyacetophenone to (S)-1-phenyl-1,2-ethanediol.  相似文献   
999.
Encapsulation of electronic devices based on organic materials that are prone to degradation even under normal atmospheric conditions with hermetic barriers is crucial for increasing their lifetime. A challenge is to develop ultrabarriers that are impermeable, flexible, and preferably transparent. Another important requirement is that they must be compatible with organic electronics fabrication schemes (i.e., must be solution processable, deposited at room temperature and be chemically inert). Here, a lifetime increase of 1300 h for poly(3‐hexylthiophene) (P3HT) films encapsulated by uniform and continuous thin (≈10 nm) films of reduced graphene oxide (rGO) is reported. This level of protection against oxygen/water vapor diffusion is substantially better than conventional polymeric barriers such as Cytop, which degrades after only 350 h despite being 400 nm thick. Analysis using atomic force microscopy, X‐ray photoelectron spectroscopy, and high‐resolution transmission electron microscopy suggest that the superior oxygen gas/moisture barrier property of rGO is due to the close interlayer distance packing and absence of pinholes within the impermeable sheets. These material properties can be correlated to the enhanced lag time of 500 h. The results provide new insight for the design of high‐performance and solution‐processable transparent ultrabarriers for a wide range of encapsulation applications.  相似文献   
1000.
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