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991.
992.
Psoralea corylifolia (P corylifolia) has been popularly applied in traditional Chinese medicine decoction for treating osteoporosis and promoting fracture healing since centuries ago. However, the bioactive natural components remain unknown. In this study, applying comprehensive two‐dimensional cell membrane chromatographic/C18 column/time‐of‐flight mass spectrometry (2D CMC/C18 column/TOFMS) system, neobavaisoflavone (NBIF), for the first time, was identified for the bioaffinity with RAW 264.7 cells membranes from the extracts of P corylifolia. Here, we revealed that NBIF inhibited RANKL‐mediated osteoclastogenesis in bone marrow monocytes (BMMCs) and RAW264.7 cells dose dependently at the early stage. Moreover, NBIF inhibited osteoclasts function demonstrated by actin ring formation assay and pit‐formation assay. With regard to the underlying molecular mechanism, co‐immunoprecipitation showed that both the interactions of RANK with TRAF6 and with c‐Src were disrupted. In addition, NBIF inhibited the phosphorylation of P50, P65, IκB in NF‐κB pathway, ERK, JNK, P38 in MAPKs pathway, AKT in Akt pathway, accompanied with a blockade of calcium oscillation and inactivation of nuclear translocation of nuclear factor of activated T cells cytoplasmic 1 (NFATc1). In vivo, NBIF inhibited osteoclastogenesis, promoted osteogenesis and ameliorated bone loss in ovariectomized mice. In summary, P corylifolia‐derived NBIF inhibited RANKL‐mediated osteoclastogenesis by suppressing the recruitment of TRAF6 and c‐Src to RANK, inactivating NF‐κB, MAPKs, and Akt signalling pathways and inhibiting calcium oscillation and NFATc1 translocation. NBIF might serve as a promising candidate for the treatment of osteoclast‐associated osteopenic diseases.  相似文献   
993.
Sirtuin 5 (SIRT5) is a NAD+‐dependent class III protein deacetylase, and its role in prostate cancer has not yet been reported. Therefore, to explore the diagnosis and treatment of prostate cancer, we investigated the effect of SIRT5 on prostate cancer. Sirtuin 5 was assessed by immunohistochemistry in 57 normal and cancerous prostate tissues. We found that the tissue expression levels of SIRT5 in patients with Gleason scores ≥7 were significantly different from those in patients with Gleason scores <7 (P < .05, R > 0). Further, mass spectrometry and pathway screening experiments showed that SIRT5 regulated the activity of the mitogen‐activated protein kinase (MAPK) pathway, which in turn modulated the expression of MMP9 and cyclin D1. Being a substrate of SIRT5, acetyl‐CoA acetyltransferase 1 (ACAT1) was regulated by SIRT5. SIRT5 also regulated MAPK pathway activity through ACAT1. These results revealed that SIRT5 promoted the activity of the MAPK pathway through ACAT1, increasing the ability of prostate cancer cells to proliferate, migrate and invade. Overall, these results indicate that SIRT5 expression is closely associated with prostate cancer progression. Understanding the underlying mechanism may provide new targets and methods for the diagnosis and treatment of the disease.  相似文献   
994.
995.
Recent studies have demonstrated a marked decrease in peripheral lymphocyte levels in patients with coronavirus disease 2019 (COVID‐19) caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Few studies have focused on the changes of NK, T‐ and B‐cell subsets, inflammatory cytokines and virus‐specific antibodies in patients with moderate COVID‐19. A total of 11 RT‐PCR‐confirmed convalescent patients with COVID‐19 and 11 patients with non‐SARS‐CoV‐2 pneumonia (control patients) were enrolled in this study. NK, CD8+ T, CD4+ T, Tfh‐like and B‐cell subsets were analysed using flow cytometry. Cytokines and SARS‐CoV‐2‐specific antibodies were analysed using an electrochemiluminescence immunoassay. NK cell counts were significantly higher in patients with COVID‐19 than in control patients (P = 0.017). Effector memory CD8+ T‐cell counts significantly increased in patients with COVID‐19 during a convalescent period of 1 week (P = 0.041). TIM‐3+ Tfh‐like cell and CD226+ Tfh‐like cell counts significantly increased (P = 0.027) and decreased (P = 0.022), respectively, during the same period. Moreover, ICOS+ Tfh‐like cell counts tended to decrease (P = 0.074). No abnormal increase in cytokine levels was observed. The high expression of NK cells is important in innate immune response against SARS‐CoV‐2. The increase in effector memory CD8+ T‐cell counts, the up‐regulation of inhibitory molecules and the down‐regulation of active molecules on CD4+ T cells and Tfh‐like cells in patients with COVID‐19 would benefit the maintenance of balanced cellular and humoural immune responses, may prevent the development of severe cases and contribute to the recovery of patients with COVID‐19.  相似文献   
996.
Pancreatic cancer (PC) is a leading cause of cancer‐related mortality globally. Though increasing evidence has demonstrated that circular RNAs (circRNAs) are linked to the development and progression of cancers, the biological functions of circRNAs in PC remain largely unexplored so far. Based on previous studies, Hsc_circ_0075829 (circ_0075829) was screened out and then further identified in PC clinical specimens and cell lines by real‐time PCR. After the stability tests, a series of in vitro and in vivo functional experiments were performed to investigate the role of circ_0075829 in PC development. Furthermore, fluorescent in situ hybridization (FISH), bioinformatics tools, dual‐luciferase assays and rescue experiments were conducted to clarify the regulatory mechanisms of circ_0075829 in SW1990 and BxPC‐3 cells. Compared with paracancerous tissues, the expression of circ_0075829 was increased in PC tissues, which was positively correlated with the clinical features of PC. Knockdown of circ_0075829 significantly suppressed the proliferative, migratory and invasive rates of SW1990 and BxPC‐3 cells both in vitro and in vivo. Bioinformatics analysis and dual‐luciferase reporter gene assay indicated that circ_0075829 could bind to miR‐1287‐5p. Mechanism research and rescue experiments demonstrated that circ_0075829 could regulate the LAMTOR3/p‐ERK signalling pathway via sponging miR‐1287‐5p in PC cell lines. Our data reveal that the circ_0075829 could facilitate the proliferation and metastasis of PC through circ_0075829/miR‐1287‐5p/LAMTOR3 axis.  相似文献   
997.
Developing effective and eco‐friendly antimicrobials and pesticides has become a highly important issue. The repellent, insecticidal and antimicrobial activity of essential oils (EOs) isolated by hydrodistillation from dried leaves of the three Eucalyptus species (E. cloeziana, E. umbellata and E. benthamii) were investigated. During GC/MS analysis, α‐pinene (47.36 %), 1,8‐cineol (38.53 %) and α‐pinene (35.31 %) were identified as major components of E. cloeziana, E. umbellata and E. benthamii, respectively. The EOs from E. cloeziana exhibited the longest effective protection time (465 min, at 50.0 % w/w) for humans among the EOs studied. The effective protection time was 30 min and 300 min at concentrations of 12.5 % (w/w) and 25.0 % (w/w), respectively. Fumigating insecticidal activity of EOs from three Eucalyptus species was tested by airtight fumigation in conical flask, which indicated that essential oils had a highly and rapidly insecticidal activity on Culex pipiens quinquefasciatus. The antimicrobial activity of EOs was evaluated by using disc diffusion and agar dilution methods. There was no significant difference in the antibacterial activity of EOs from E. cloeziana and E. umbellate and they had the same MICs (20 mL/L) on Staphylococcus aureus, Salmonella typhi, Bacillus subtilis and Escherichia coli. E. benthamii had the worst microbial inhibitory effect among the three Eucalyptus essential oils and the MIC value for the test species is 40 mL/L except for Rhodotorula Harrison (10 mL/L).  相似文献   
998.
Cisplatin resistance is one of the main obstacles in the treatment of advanced nasopharyngeal carcinoma (NPC). AKR1C1 is a member of the Aldo-keto reductase superfamily (AKRs), which converts aldehydes and ketones to their corresponding alcohols and has been reported to be involved in chemotherapeutic resistance of multiple drugs. The expression and function of AKR1C1 in NPC have not been reported until now. The aim of this research was to investigate the expression of AKR1C1 and it is role in cisplatin resistance in NPC. AKR1C1 protein expression was detected by immunohistochemistry in human NPC tissues and by Western blot assays in NPC and immortalized nasopharyngeal epithelial cells. The effects of AKR1C1 knock-down by siRNA on proliferation, migration and invasion in NPC cells were evaluated by CCK8, wound healing and transwell assays. To evaluate the effects of AKR1C1 silencing on cisplatin sensitivity in NPC cells, CCK8 assays were used to detect cell proliferation, flow cytometry was used to detect cell cycle distribution, and flow cytometry and DAPI staining were used to detect cell apoptosis. AKR1C1 down-regulation was associated with advanced clinicopathological characters such as larger tumor size, more lymphatic nodes involvement, with metastasis and later clinical stages, while AKR1C1 down-regulation was a good prognostic factor for overall survival (OS) in NPC patients. In vitro study showed that AKR1C1 was not directly involved in the malignant biological behaviours such as proliferation, cell cycle progression and migration of NPC cells, whereas AKR1C1 knock-down could enhance cisplatin sensitivity of NPC cells. These results suggest that AKR1C1 is a potential marker for predicting cisplatin response and could serve as a molecular target to increase cisplatin sensitivity in NPC.  相似文献   
999.
The role of exosomes derived from endothelial cells (ECs) in the progression of atherosclerosis (AS) and inflammation remains largely unexplored. We aimed to investigate whether exosome derived from CD137‐modified ECs (CD137‐Exo) played a major role in AS and to elucidate the potential mechanism underlying the inflammatory effect. Exosomes derived from mouse brain microvascular ECs treated with agonist anti‐CD137 antibody were used to explore the effect of CD137 signalling in AS and inflammation in vitro and vivo. CD137‐Exo efficiently induced the progression of AS in ApoE?/? mice. CD137‐Exo increased the proportion of Th17 cells both in vitro and vivo. The IL‐6 contained in CD137‐Exo which is regulated by Akt and NF‐КB pathway was verified to activate Th17 cell differentiation. IL‐17 increased apoptosis, inhibited cell viability and improved lactate dehydrogenase (LDH) release in ECs subjected to inflammation induced by lipopolysaccharide (LPS). The expression of soluble intercellular adhesion molecule1 (sICAM‐1), monocyte chemoattractant protein‐1 (MCP‐1) and E‐selectin in the supernatants of ECs after IL‐17 treatment was dramatically increased. CD137‐Exo promoted the progression of AS and Th17 cell differentiation via NF‐КB pathway mediated IL‐6 expression. This finding provided a potential method to prevent local and peripheral inflammation in AS.  相似文献   
1000.
The heterogeneity in prognoses and chemotherapeutic responses of colon cancer patients with similar clinical features emphasized the necessity for new biomarkers that help to improve the survival prediction and tailor therapies more rationally and precisely. In the present study, we established a s troma-related l ncRNA s ignature (SLS) based on 52 lncRNAs to comprehensively predict clinical outcome. The SLS model could not only distinguish patients with different recurrence and mortality risks through univariate analysis, but also served as an independent factor for relapse-free and overall survival. Compared with the conventionally used TNM stage system, the SLS model clearly possessed higher predictive accuracy. Moreover, the SLS model also effectively screened chemotherapy-responsive patients, as only patients in the low-SLS group could benefit from adjuvant chemotherapy. The following cell infiltration and competing endogenous RNA (ceRNA) network functional analyses further confirmed the association between the SLS model and stromal activation-related biological processes. Additionally, this study also identified three phenotypically distinct colon cancer subtypes that varied in clinical outcome and chemotherapy benefits. In conclusion, our SLS model may be a significant determinant of survival and chemotherapeutic decision-making in colon cancer and may have a strong clinical transformation value.  相似文献   
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