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991.
Zhihua Ye Dingwen Gui Xiaoying Wang Jing Wang Jinlun Fu 《Journal of clinical laboratory analysis》2022,36(6)
BackgroundLong noncoding RNAs (LncRNAs) plays a vital role in tumorigenesis and development. The molecular mechanism of SNHG1 in renal cell carcinoma (RCC) has not been illustrated. The aim of this research was to explore the expression and function of LncRNA SNHG1 in RCC.Material and MethodsThe expression of SNHG1 in clinical tissues and RCC cell lines was detected. Luciferase reporter assay was performed to verify the correlation between SNHG1, miR‐103a, and HMGA2. CCK‐8 assay was performed to examine cell viability. Cell apoptosis was analyzed using flow cytometry. Cell invasion capacity was determined by Transwell assays. The protein level of HMGA2 was analyzed by Western blotting.ResultsThe expression of SNHG1 markedly increased in RCC tissues and cell lines. Subsequent studies identified SNHG1 as a miRNA sponge for miR‐103a. In addition, SNHG1 knockdown and miR‐103a overexpression significantly inhibited progression of RCC. miR‐103a also regulated HMGA2 levels.ConclusionOur findings showed that SNHG1 was upregulated in RCC cells and tissues. SNHG1 promoted the malignant characteristics of RCC cells. Its regulatory effect may be regulation of HMGA2 by sponging miR‐103a. Therefore, Our study facilitates the understanding of SNHG1 function in RCC. 相似文献
992.
Lijing Ma Jiaxin Xu Qisheng Tang Yu Cao Ruize Kong Kunlin Li Jie Liu Lihong Jiang 《Journal of clinical laboratory analysis》2022,36(6)
BackgroundSolute carrier family 2 member 3 (SLC2A3), is a member of a superfamily of transport protein genes. SLC2A3 played an important role in embryonic development. Previous research reported SLC2A3 duplication was reportedly associated with congenital syndromic heart defects. However, it is not clear whether the gene is associated with non‐syndromic congenital heart disease. Our study aimed to elucidate the relationship between its variation and congenital heart disease.MethodsGenomic DNA extracted from the peripheral blood leukocytes of two families with CHD were sequenced with whole‐exome sequencing to identify variations, used Sanger sequencing to investigate SLC2A3 variants in 494 Chinese patients with CHD and 576 healthy unrelated individuals.ResultsIn members from the two families, three with CHD had the SLC2A3 (rs3931701) C > T variant. Of the 494 patients with CHD, 394 had gene variants (86 had the TT type and 308 had the CT type). Of the 576 healthy controls, 272 participants had gene variants (36 had the TT type and 236 had the CT type). The TT type [p < 0.0001, odds ratio (OR) =7.262, 95% confidence interval (CI) =4.631–11.388] and CT type (p < 0.0001, OR =3.967, 95% CI =2.991–5.263) of SLC2A3 (rs3931701) significantly increased the risk of sporadic ASD in a Chinese Yunnan population.ConclusionsSingle nucleotide variations of SLC2A3, particularly, the SLC2A3 (rs3931701) C > T variant increased the risk of CHD among the studied population. 相似文献
993.
葛根芩连汤出自《伤寒杂病论》,为表里双解治疗协热下利的代表方剂,全方由葛根、黄芩、黄连、炙甘草配伍而成,四药合用可外疏内清,共达清热止利,表里同解之效。现临床上基于异病同治的原则将葛根芩连汤用于2型糖尿病(T2DM)的治疗,取得了良好的疗效。T2DM是一种以血糖水平升高为主要特征的慢性代谢性疾病,其病因和发病机制十分复杂,主要与遗传、生活方式、环境及饮食等因素相关。临床观察及实验研究显示,葛根芩连汤及其药效成分可有效防治T2DM。临床上常将葛根芩连汤加减应用或联合西药应用,其治疗效果明显优于单独使用西药。临床实践证实葛根芩连汤可以有效缓解T2DM患者临床症状,减轻胃肠道等不良反应,并减少并发症的发生。实验研究表明葛根芩连汤可通过调控胰岛传导通路及炎症信号通路、缓解氧化应激反应、调节肠道菌群等方式来增强患者胰岛功能,改善胰岛素抵抗,从而治疗T2DM。但目前关于葛根芩连汤通过改善胰岛素抵抗治疗T2DM的机制尚待进一步研究,故该文就葛根芩连汤改善T2DM胰岛素抵抗的临床及实验基础研究进展进行系统综述,以期为葛根芩连汤治疗T2DM作用机制的后续深入研究及其临床防治提供理论和数据参考。 相似文献
994.
995.
Jaehyun Bae Young-eun Kim Minyoung Lee Yong-ho Lee Byung-Wan Lee Bong-Soo Cha Eun Seok Kang 《Yonsei medical journal》2022,63(6):539
PurposeTo date, no study has compared the effects of adding sodium glucose cotransporter-2 (SGLT-2) inhibitors to the combination of metformin plus dipeptidyl peptidase-4 (DPP-4) inhibitors to the effects of adding other conventional anti-diabetic drugs (ADDs) to the dual therapy. We aimed to compare the effect of adding SGLT-2 inhibitors with that of adding sulfonylurea (SU) in type 2 diabetes (T2D) patients inadequately controlled with metformin plus DPP-4 inhibitors.Materials and MethodsThis study was designed to evaluate the non-inferiority of SGLT-2 inhibitor to SU as an add-on therapy to the dual combination of metformin plus DPP-4 inhibitors. A total of 292 T2D patients who started SU or SGLT-2 inhibitors as an add-on therapy to metformin plus DPP-4 inhibitors due to uncontrolled hyperglycemia, defined as glycated hemoglobin (HbA1c) ≥7%, were recruited. After propensity score matching, 90 pairs of patients remained, and 12-week changes in HbA1c levels were reviewed to assess glycemic effectiveness. Data from these patients were analyzed retrospectively.ResultsAfter 12 weeks of triple therapy, both groups showed significant changes in HbA1c levels, with a mean of -0.9% in each group. The inter-group difference was 0.01% [95% confidence interval (CI): -0.26–0.27], and the upper limit of the 95% CI was within the limit for non-inferiority (0.40%). There were no inter-group differences in the changes of liver enzyme levels and kidney function.ConclusionAdding SGLT-2 inhibitors is not inferior to adding SU as a third-line ADD to metformin plus DPP-4 inhibitor combination therapy. 相似文献
996.
Jessica Hong Hyung Joon Kwon Raul Cachau Catherine Z. Chen Kevin John Butay Zhijian Duan Dan Li Hua Ren Tianyuzhou Liang Jianghai Zhu Venkata P. Dandey Negin P. Martin Dominic Esposito Uriel Ortega-Rodriguez Miao Xu Mario J. Borgnia Hang Xie Mitchell Ho 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(18)
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike is a trimer of S1/S2 heterodimers with three receptor-binding domains (RBDs) at the S1 subunit for human angiotensin-converting enzyme 2 (hACE2). Due to their small size, nanobodies can recognize protein cavities that are not accessible to conventional antibodies. To isolate high-affinity nanobodies, large libraries with great diversity are highly desirable. Dromedary camels (Camelus dromedarius) are natural reservoirs of coronaviruses like Middle East respiratory syndrome CoV (MERS-CoV) that are transmitted to humans. Here, we built large dromedary camel VHH phage libraries to isolate nanobodies that broadly neutralize SARS-CoV-2 variants. We isolated two VHH nanobodies, NCI-CoV-7A3 (7A3) and NCI-CoV-8A2 (8A2), which have a high affinity for the RBD via targeting nonoverlapping epitopes and show broad neutralization activity against SARS-CoV-2 and its emerging variants of concern. Cryoelectron microscopy (cryo-EM) complex structures revealed that 8A2 binds the RBD in its up mode with a long CDR3 loop directly involved in the ACE2 binding residues and that 7A3 targets a deeply buried region that uniquely extends from the S1 subunit to the apex of the S2 subunit regardless of the conformational state of the RBD. At a dose of ≥5 mg/kg, 7A3 efficiently protected transgenic mice expressing hACE2 from the lethal challenge of variants B.1.351 or B.1.617.2, suggesting its therapeutic use against COVID-19 variants. The dromedary camel VHH phage libraries could be helpful as a unique platform ready for quickly isolating potent nanobodies against future emerging viruses.Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of COVID-19 (1, 2) that enters human cells by binding its envelope anchored type I fusion protein (spike) to angiotensin-converting enzyme 2 (ACE2) (3, 4). The SARS-CoV-2 spike is a trimer of S1/S2 heterodimers with three ACE2 receptor-binding domains (RBDs) attached to the distal end of the spike via a hinge region that allows conformational flexibility (4). In the all-down conformation, the RBDs are packed with their long axes contained in a plane perpendicular to the axis of symmetry of the trimer. Transition to the roughly perpendicular up conformation exposes the receptor-binding motif (RBM), located at the distal end of the RBD, which is sterically occluded in the down state. Numerous neutralizing antibodies targeting the spike, particularly its RBD, have been developed to treat COVID-19 using common strategies such as single B cell cloning, animal immunization, and phage display (5–9). Most vaccines, including those that are messenger RNA based, are designed to induce immunity against the spike or RBD (10–12). However, emerging SARS-CoV-2 variants such as D614G, B.1.1.7 (Alpha, United Kingdom), B.1.351 (Beta, South Africa), and P.1 (Gamma, Brazil) have exhibited increased resistance to neutralization by monoclonal antibodies or postvaccination sera elicited by the COVID-19 vaccines (13, 14). Monoclonal antibodies with Emergency Use Authorization for COVID-19 treatment partially (Casirivimab) or completely (Bamlanivimab) failed to inhibit the B.1.351 and P.1 variants. Similarly, these variants were less effectively inhibited by convalescent plasma and sera from individuals vaccinated with a COVID-19 vaccine (BNT162b2) (13). The B.1.617.2 (Delta, India) variant became the prevailing strain in many countries (15). Highly effective and broadly neutralizing antibody therapy is urgently demanded for COVID-19 patients.Due to their small size and unique conformations, camelid VHH single-domain antibodies (also known as nanobodies) can recognize protein cavities that are not accessible to conventional antibodies (16). To isolate high-affinity nanobodies without a need for further affinity maturation, it is highly desirable to construct large nanobody libraries with great diversity. Dromedary camels have been found as potential natural reservoirs of Middle East respiratory syndrome CoV (MERS-CoV) (17). We speculated that dromedary camels would be an ideal source of neutralizing nanobodies against coronaviruses. In the present study, we built large camel VHH single-domain antibody phage libraries with a diversity of over 1011 from six dromedary camels (Camelus dromedarius), three males and three females, with ages ranging from 3 mo to 20 y. We used both the SARS-CoV-2 RBD and the stabilized spike ectodomain trimer protein as baits to conduct phage panning for nanobody screening. Among all the binders, we found NCI-CoV-7A3 (7A3), NCI-CoV-1B5 (1B5), NCI-CoV-8A2 (8A2), and NCI-CoV-2F7 (2F7) to be potent ACE2 blockers. In addition, these dromedary camel nanobodies displayed potent neutralization activity against the B.1.351 and B.1.1.7 variants and the original strain (Wuhan-Hu-1). The cryoelectron microscopy (cryo-EM) structure of the spike trimer protein complex with these VHH nanobodies revealed two distinct nonoverlapping epitopes for neutralizing SARS-CoV-2. In particular, 7A3 recognizes a unique and deeply buried region that extends to the apex of the S2 subunit of the spike. Combined treatment with 7A3 and 8A2 shows more potent protection against various variants in culture and mice infected with the B.1.351 variant. Interestingly, 7A3 alone retains its neutralization activity against the lethal challenge of the B.1.617.2 variant in mice. 相似文献
997.
Attapulgite (ATP) disaggregated by a ball milling–freezing process was used to support Fe/Ni bimetallic nanoparticles (nFe/Ni) to obtain a composite material of D-ATP-nFe/Ni for the dechlorination degradation of 2,4-dichlorophenol (2,4-DCP), thus improving the problem of agglomeration and oxidation passivation of nanoscale zero-valent iron (nFe) in the dechlorination degradation of chlorinated organic compounds. The results show that Fe/Ni nanoparticle clusters were dispersed into single spherical particles by the ball milling–freezing-disaggregated attapulgite, in which the average particle size decreased from 423.94 nm to 54.51 nm, and the specific surface area of D-ATP-nFe /Ni (97.10 m2/g) was 6.9 times greater than that of nFe/Ni (14.15 m2/g). Therefore, the degradation rate of 2,4-DCP increased from 81.9% during ATP-nFe/Ni application to 96.8% during D-ATP-nFe/Ni application within 120 min, and the yield of phenol increased from 57.2% to 86.1%. Meanwhile, the reaction rate Kobs of the degradation of 2,4-DCP by D-ATP-nFe/Ni was 0.0277 min−1, which was higher than that of ATP-nFe/Ni (0.0135 min−1). In the dechlorination process of 2,4-DCP by D-ATP-nFe/Ni, the reaction rate for the direct dechlorination of 2,4-DCP of phenol (k5 = 0.0156 min−1) was much higher than that of 4-chlorophenol (4-CP, k2 = 0.0052 min−1) and 2-chlorophenol (2-CP, k1 = 0.0070 min−1), which suggests that the main dechlorination degradation pathway for the removal of 2,4-DCP by D-ATP-nFe/Ni was directly reduced to phenol by the removal of two chlorine atoms. In the secondary pathway, the removal of one chlorine atom from 2,4-DCP to generate 2-CP or 4-CP as intermediate was the rate controlling step. The final dechlorination product (phenol) was obtained when the dechlorination rate accelerated with the progress of the reaction. This study contributes to the broad topic of organic pollutant treatment by the application of clay minerals. 相似文献
998.
999.
目的 研究吡格列酮对缺血再灌注损伤心肌细胞的保护作用机制中PI3K/AKT/Bcl-2信号通路的作用.方法 取Wistar大鼠乳鼠心室肌细胞进行体外培养,缺氧、复氧各3 h后建立缺血再灌注损伤细胞模型.采用免疫细胞化学染色法检测细胞内Bcl-2蛋白含量,采用Western-bloting检测细胞内Bcl-2蛋白表达水平.结果 免疫细胞化学染色法及Western-bloting结果均显示:与Ⅰ组比较,P组Bcl-2表达明显增加(P〈0.05);与P组比较,P+Ly组Bcl-2表达明显减少(P〈0.05).结论 吡格列酮减轻心肌缺血再灌注损伤保护机制与其激活PI3K/AKT/ Bcl-2信号通路有关. 相似文献
1000.