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991.
Shengsheng Liu Meiying Wu Ertai A Shucai Wu Shujun Geng Zhihui Li Mingwu Li Liang Li Yu Pang Wanli Kang Shenjie Tang 《Medicine》2021,100(8)
The T-SPOT.TB assay detects cellular immune responses to 2 core Mycobacterium tuberculosis antigens, early secreted antigenic target of 6-kDa protein (ESAT-6) and culture filtrate protein-10 (CFP-10). T-SPOT.TB has been recently used for auxiliary diagnosis of active pulmonary tuberculosis (PTB). However, testing can produce inconsistent results due to differential PTB patient immune responses to these antigens, prompting us to identify factors underlying inconsistent results.Data were retrospectively analyzed from 1225 confirmed PTB patients who underwent T-SPOT.TB testing at 5 specialized tuberculosis hospitals in China between December 2012 and November 2015. Numbers of spot-forming cells (SFCs) reflecting T cell responses to ESAT-6 and CFP-10 antigens were recorded then analyzed via multivariable logistic regression to reveal factors underlying discordant T cell responses to these antigens.The agreement rate of 84.98% (82.85%–86.94%) between PTB patient ESAT-6 and CFP-10 responses demonstrated high concordance. Additionally, positivity rates were higher for ESAT-6 than for CFP-10 (84.8% vs 80.7%, P < .001), with ESAT-6 and CFP-10 microwell SFC numbers for each single positive group not differing significantly (P > .99), while spot numbers of the single positive group were lower than numbers for the double positive group (P < .001). Elderly patients (aged ≥66 years) and patients receiving retreatment were most likely to have discordance results.ESAT-6 promoted significantly more positive T-SPOT.TB results than did CFP-10 in PTB patients. Advanced age and retreatment status were correlated with discordant ESAT-6 and CFP-10 results. Assessment of factors underlying discordance may lead to improved PTB diagnosis using T-SPOT.TB. 相似文献
992.
993.
Background:Transarterial chemoembolization (TACE) has the characteristics of minimally invasive, strong repeatability, and good curative effect, so it is commonly used in the nonoperative treatment of hepatocellular carcinoma (HCC). However, infection will occur after TACE, which not only increases the hospitalization time and medical expenses, but also affects the efficacy of TACE treatment. At present, there is a lack of analysis of the risk factors of infection after TACE of patients with HCC. In this study, meta-analysis was used to further explore the risk factors of postoperative infection in patients with HCC after TACE, and to provide strategies for infection prevention and intervention.Methods:To search the literatures about the influencing factors of post-TACE infection in patients with HCC published from the establishment of PubMed, Embase, The Cochrane Library, Web of Science, China Biology Medicine Database, China National Knowledge Infrastructure, China Science and Technology Journal Database, and WANFANG to April 2021. Screening was carried out according to inclusion criteria and exclusion criteria. A meta-analysis was performed using RevMan 5.3 software.Results:We disseminated the findings of this systematic review and meta-analysis via publications in peer-reviewed journals.Conclusion:This study systematically reviewed the existing evidence and determined the incidence and predictors of infection after TACE of patients with HCC.Ethics and dissemination:The private information from individuals will not be published. This systematic review also should not damage participants’ rights. Approval from an ethics committee is not required for this study. The results may be published in a peer-reviewed journal or disseminated in relevant conferences.OSF Registration number:DOI 10.17605/OSF.IO/26P5X 相似文献
994.
Aim:
Wogonin (5,7-dihydroxy-8-methoxyflavone), a major bioactive compound of the flavonoid family, is commonly extracted from the traditional Chinese medicine Scutellaria baicalensis and possesses antioxidant and anti-inflammatory activities and is assumed to have anti-diabetes function. Indeed, a current study has shown that it can possibly treat metabolic disorders such as those found in db/db mice. However, the underlying molecular mechanism remains largely unclear. The aim of this study was to investigate the impact of wogonin on osteopontin (OPN) expression in adipose tissue from type 1 diabetic mice and in 3T3-L1 adipocytes.Methods:
Type 1 diabetes was induced by streptozotocin (STZ) injection. 3T3-L1 preadipocytes were converted to 3T3-L1 adipocytes through treatment with insulin, dexamethasone, and 3-isobutyl-1-methylxanthine (IBMX). Western blot analysis and RT-PCR were performed to detect protein expression and mRNA levels, respectively.Results:
Wogonin treatment suppressed the increase in serum OPN levels and reduced OPN expression in adipose tissue from STZ-induced type 1 diabetic mice. Administration of wogonin enhanced PPARα expression and activity. Silencing of PPARα diminished the inhibitory effects of wogonin on OPN expression in 3T3-L1 adipocytes. Furthermore, the levels of c-Fos and phosphorylated c-Jun were reduced in wogonin-treated adipose tissue and 3T3-L1 adipocytes. In addition, wogonin treatment dramatically mitigated p38 MAPK phosphorylation. Pharmacological inhibition of p38 MAPK by its specific inhibitor SB203580 increased PPARα activity and decreased OPN expression.Conclusion:
Our results suggest that wogonin downregulated OPN expression in adipocytes through the inhibition of p38 MAPK and the sequential activation of the PPARα pathway. Given the adverse effects of high OPN levels on metabolism, our results provide evidence for the potential administration of wogonin as a treatment for diabetes. 相似文献995.
Chen Wang Yu-fang Chen Xiao-qing Quan Huan Wang Rui Zhang Jun-hua Xiao Jia-ling Wang Cun-tai Zhang Ji-zhou Xiang Qiang Tang 《Acta pharmacologica Sinica》2015,36(12):1451-1461
Aim:
Neferine is an isoquinoline alkaloid isolated from seed embryos of Nelumbo nucifera (Gaertn), which has a variety of biological activities. In this study we examined the effects of neferine on Kv4.3 channels, a major contributor to the transient outward current (Ito) in rabbit heart, and on ex vivo electrophysiology of rabbit hearts.Methods:
Whole-cell Kv4.3 currents were recorded in HEK293 cells expressing human cardiac Kv4.3 channels using patch-clamp technique. Arterially perfused wedges of rabbit left ventricles (LV) were prepared, and transmembrane action potentials were simultaneously recorded from epicardial (Epi) and endocardial (Endo) sites with floating microelectrodes together with transmural electrocardiography (ECG).Results:
Neferine (0.1–100 μmol/L) dose-dependently and reversibly inhibited Kv4.3 currents (the IC50 value was 8.437 μmol/L, and the maximal inhibition at 100 μmol/L was 44.12%). Neferine (10 μmol/L) caused a positive shift of the steady-state activation curve of Kv4.3 currents, and a negative shift of the steady-state inactivation curve. Furthermore, neferine (10 μmol/L) accelerated the inactivation but not the activation of Kv4.3 currents, and markedly slowed the recovery of Kv4.3 currents from inactivation. Neferine-induced blocking of Kv4.3 currents was frequency-dependent. In arterially perfused wedges of rabbit LV, neferine (1, 3, and 10 μmol/L) dose-dependently prolonged the QT intervals and action potential durations (APD) at both Epi and Endo sites, and caused dramatic increase of APD10 at Epi sites.Conclusion:
Neferine inhibits Kv4.3 channels likely by blocking the open state and inactivating state channels, which contributes to neferine-induced dramatic increase of APD10 at Epi sites of rabbit heart. 相似文献996.
Tang Xin-Ying Ru Nan Li Qing Qian Yang-Yang Sun Hui Zhu Jia-Hui He Lin Wang Yuan-Chen Hu Liang-Hao Li Zhao-Shen Zou Wen-Bin Liao Zhuan 《Digestive diseases and sciences》2021,66(11):4008-4016
Digestive Diseases and Sciences - The high incidence of osteopathy among patients with chronic pancreatitis (CP) has garnered increased attention over recent years. The aims of this study were to... 相似文献
997.
This study explored the effects of humic acid (HA) on the toxicity of ZnO nanoparticles (nano‐ZnO) and Zn2+ to Anabaena sp. Typical chlorophyll fluorescence parameters, including effective quantum yield, photosynthetic efficiency and maximal electron transport rate, were measured by a pulse‐amplitude modulated fluorometer. Results showed that nano‐ZnO and Zn2+ could inhibit Anabaena sp. growth with the EC50 (concentration for 50% of maximal effect) of 0.74 ± 0.01 and 0.3 ± 0.01 mg/L, respectively. In the presence of 3.0 mg/L of HA, EC50 of nano‐ZnO increased to 1.15 ± 0.04 mg/L and EC50 of Zn2+ was still 0.3 ± 0.01 mg/L. Scanning electron microscopy observation revealed that HA prevented the adhesion of nano‐ZnO on the algae cells due to the increased electrostatic repulsion. The generation of intracellular reactive oxygen species and cellular lipid peroxidation were significantly limited by HA. Nano‐ZnO had more damage to the cell membrane than Zn2+ did, which could be proven by the malondialdehyde content in Anabaena sp. cells. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 895–903, 2015. 相似文献
998.
Background:Post-traumatic stress disorder (PTSD) is one of the most commonly reported mental health consequences, followed by disasters and traumatic events, either natural or man-made. At present, there are no unified results for the prevalence rate of PTSD in patients suffering from acute trauma and related influencing factors. Therefore, the purpose of this study is to systematically evaluate the existing literatures, thus obtaining a comprehensive estimation of the combined prevalence rate of PTSD and related factors in trauma patients, so as to provide evidence support for clinical disease prediction models and intervention strategies.Methods:Published articles will be retrieved from PubMed, Embase, Cochrane Library, Web of Science, China Biology Medicine Database, China National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang Database. Research reports will be searched in March 2021. STATA 14.0 software will be applied for data analysis. Mantel–Haenszel fixed effect model or DerSimonian–Laird random effect model will be selected to estimate the pooled prevalence of PTSD in patients with acute trauma and associated factors.Results:We will disseminate the findings of this systematic review and meta-analysis via publications in peer-reviewed journals.Conclusions:The results of this analysis can be used to establish a risk prediction model of PTSD in patients experiencing acute trauma, so as to provide intervention strategies.OSF Registration Number:DOI 10.17605/OSF.IO/Z275U. 相似文献
999.
1000.
Effects of diallyl trisulfide on induction of apoptotic death in murine leukemia WEHI‐3 cells in vitro and alterations of the immune responses in normal and leukemic mice in vivo 下载免费PDF全文
Fang‐Ming Hung Hung‐Sheng Shang Nou‐Ying Tang Jen‐Jyh Lin Kung‐Wen Lu Jing‐Pin Lin Yang‐Ching Ko Chien‐Chih Yu Hai‐Lung Wang Jung‐Chi Liao Hsu‐Feng Lu Jing‐Gung Chung 《Environmental toxicology》2015,30(11):1343-1353
Diallyl trisulfide (DATS), a chemopreventive dietary constituent and extracted from garlic, has been shown to against cultured many types of human cancer cell liens but the fate of apoptosis in murine leukemia cells in vitro and immune responses in leukemic mice remain elusive. Herein, we clarified the actions of DATS on growth inhibition of murine leukemia WEHI‐3 cells in vitro and used WEHI‐3 cells to generate leukemic mice in vivo, following to investigate the effects of DATS in animal model. In in vitro study, DATS induced apoptosis of WEHI‐3 cells through the G0/G1 phase arrest and induction of caspase‐3 activation. In in vivo study DATS decreased the weight of spleen of leukemia mice but did not affect the spleen weight of normal mice. DATS promoted the immune responses such as promotions of the macrophage phagocytosis and NK cell activities in WEHI‐3 leukemic and normal mice. However, DATS only promotes NK cell activities in normal mice. DATS increases the surface markers of CD11b and Mac‐3 in leukemia mice but only promoted CD3 in normal mice. In conclusion, the present study indicates that DATS induces cell death through induction of apoptosis in mice leukemia WHEI‐3 cells. DATS also promotes immune responses in leukemia and normal mice in vivo. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1343–1353, 2015. 相似文献