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排序方式: 共有9782条查询结果,搜索用时 15 毫秒
1.
目的:探究三结构域蛋白59(TRIM59)调控人皮肤黑色素瘤细胞SK-MEL-2增殖、细胞周期、凋亡及迁移侵袭的作用机制,及其与Bcl2相关转录因子1(BCLAF1)之间的关系。方法:qPCR和WB法检测人表皮黑色素细胞HEMn-LP、人皮肤黑色素瘤细胞SK-MEL-2、UACC903、A375及36例邢台市人民医院2019年2月至2021年7月收集的皮肤黑色素瘤组织中TRIM59的mRNA和蛋白表达,使用脂质体将si-con、si-TRIM59转染至SK-MEL-2细胞中,WB法检测干扰TRIM59表达对细胞中周期蛋白D1(CCND1)、细胞周期素依赖性激酶2(CDK2)、肿瘤抑制蛋白基因(TP53)和 BCLAF1 蛋白表达的影响,CCK-8法、流式细胞术、划痕愈合实验、Transwell实验检测对细胞的活性、凋亡、迁移和侵袭的影响,免疫共沉淀(Co-IP)实验检测对细胞中TRIM59蛋白与BCLAF1结合能力的影响。结果:与HEMn-LP细胞相比,SK-MEL-2、UACC903、A375细胞中TRIM59 mRNA和TRIM59、BCLAF1蛋白均呈高表达(均P<0.05),SK-MEL-2细胞中TRIM59表达水平最高。相较于si-con组和Normal组,沉默TRIM59后,SK-MEL-2细胞的活性显著降低,细胞周期阻滞于G2期,CCND1、CDK2的蛋白表达显著降低,TP53蛋白和细胞凋亡率均显著升高,划痕抑制率明显升高,迁移侵袭细胞数明显降低(均P<0.05)。免疫共沉淀实验结果显示,TRIM59与BCLAF1之间存在蛋白结合关系。TRIM59与 BCLAF1 在肿瘤组织中的表达呈显著的正相关(r=0.878,P<0.001)。结论:干扰TRIM59表达能够抑制人皮肤黑色素瘤SK-MEL-2细胞的增殖、迁移和侵袭而促进凋亡,抑制SK-MEL-2细胞的恶性生物学行为,其机制可能与TRIM59结合BCLAF1有关。  相似文献   
2.
BackgroundProsthetic choice for mitral valve replacement is generally driven by patient age and patient and surgeon preference, and current guidelines do not discriminate between different etiologies of mitral valve disease. Our objective was to assess and compare short- and long-term outcomes after mitral valve replacement among patients with biological or mechanical prostheses in the setting of severe ischemic mitral regurgitation.MethodsBetween 2000 and 2016, 424 patients underwent mitral valve replacement for severe ischemic mitral regurgitation at our institution, using biological prosthesis in 188 (44%) and mechanical prosthesis in 236 (56%). A 1:1 propensity score match (n = 126 per group) and inverse probability of treatment weighting were used to compare groups. Short-term outcomes included in-hospital mortality and other cardiovascular adverse events. Long-term outcomes included survival and hospital readmission for cardiovascular causes, stroke, and major bleeding.ResultsIn-hospital mortality and early postoperative adverse events were similar between groups in the propensity score match and inverse probability of treatment weighting cohorts. Overall long-term survival was similar at 5 and 9 years, but mechanical prosthesis recipients were more frequently readmitted to hospital for cardiovascular causes, including stroke and non-neurological bleeding in propensity score matching and inverse probability of treatment weighting analyses (all P values < .004). Type of prosthesis did not independently influence all-cause mortality (hazard ratio, 1.01; 95% confidence interval, 0.71-1.43; P = .959), but placement of a mechanical prosthesis was associated with increased risk of readmission for cardiovascular events (hazard ratio, 1.65; 95% confidence interval, 1.17-2.32; P = .004) among matched patients.ConclusionsThe type of prosthesis has no influence on long-term survival among patients with severe ischemic mitral regurgitation undergoing mitral valve replacement. There may be an increased risk of neurologic events and serious bleeding associated with mechanical prostheses.  相似文献   
3.
目的 观察结肠癌HCT116细胞健脾消癌方的条件培养液对HUVEC细胞管腔形成的影响,从PI3K/Akt生物轴调控角度探讨其作用机制。方法 培养HCT116细胞,细胞设3组:对照组,健脾消癌方组(加入15%健脾消癌方含药血清)及人参皂苷Rg3组;制备HCT116细胞健脾消癌方条件培养液(分组及制备方法见实验方法),用条件培养液干预HUVEC(脐静脉内皮细胞,Human Umbilical Vein Endothelial Cells),Matrigel基质胶法检测HCT116细胞健脾消癌方条件培养液对HUVEC小管形成的影响。随后采用蛋白免疫印迹法(Western blot)检测各组HCT116细胞磷脂酰肌醇3-激酶(PI3K)、蛋白激酶B(Akt)、p-Akt、VEGF(血管内皮生长因子,Vascular endothelial growth factor)蛋白表达。最后在结肠癌HCT116荷瘤小鼠中验证健脾消癌方对肿瘤生长速度的影响,并经瘤组织VEGF蛋白表达、CD31免疫组化染色检测肿瘤内血管生成情况。结果 模型组HUVEC细胞管腔形成较空白血清组显著增加(P<0.05);健脾消癌方组及人参皂苷Rg3组较模型组HUVEC细胞管腔形成显著减少(P<0.01)。p-Akt和VEGF蛋白表达水平模型组高于空白血清组(P<0.05),健脾消癌方组及人参皂苷Rg3组显著低于模型组(P<0.01);PI3K、Akt蛋白表达量组间差异无统计学意义。与对照组比较,模型组荷瘤小鼠肿瘤体积显著性增大,瘤组织内VEGF表达、CD31阳性面积显著性增加,差异有统计学意义(P<0.05);与模型组比较,健脾消癌方组及人参皂苷Rg3组荷瘤小鼠肿瘤体积显著减小,瘤组织内VEGF表达、CD31阳性面积降低,差异有统计学意义(P<0.05)。结论 健脾消癌方可抑制肿瘤的血管生成和生长,其作用机制可能与PI3K/Akt生物轴调控VEGF表达有关。  相似文献   
4.
ABSTRACT

Introduction

Acne is a chronic, inflammatory, and immune mediated disease of pilosebaceous unit, highly prevalent in adolescents. It involves face, trunk, and back; may leave scars and affect quality of life. Early, effective, and safe treatment is the key for disease resolution. Oral isotretinoin is the unique treatment for cure or prolonged remission for moderate and severe acne, preventing psychosocial impact and scars. It inhibits sebaceous glands activity and has anti-inflammatory and immunoregulatory properties.  相似文献   
5.
泽泻为我国传统中药,广泛应用于中医临床复方及多种中成药中。目前从泽泻中分离到了220余个化合物,包括三萜、倍半萜、二萜、糖类、含氮化合物、苯丙素、黄酮、甾体等。药理学研究表明泽泻醇提物、水提物及一些单体类成分具有利尿、抗结石及肾脏保护、降血脂及保肝、降血糖、抗癌、抗氧化损伤、抗炎、抗补体等作用。该文对近五十年来泽泻的化学成分和药理作用进行了全面系统的整理,以期为泽泻的深入研究和开发利用提供理论依据。  相似文献   
6.
Steady-state axisymmetric simulations using the Reynolds-Averaged Navier-Stokes equations have been carried out in order to optimize the performance of a Chemical, Biological, Radiological, and Nuclear (CBRN) canister filter for its use in a powered air-purifying respirator (PAPR). Alterations have been made to the shape of the canister, the spacing of the rear wall of the canister with regard to the carbon filter, and the bracketing between (i) the particulate filter and the carbon bed and (ii) the carbon bed and the canister wall. The pressure drops across the canister and the residence time distribution at the rear of the carbon bed have been analyzed in detail based on an extensive parametric analysis involving the aforementioned variations. It has been demonstrated that the non-uniform porosity profile of the carbon bed resulted in alternating regions of high and low velocity close to the canister wall, providing a possible route for breakthrough. Designs, which included a bracket at the rear of the carbon bed, blocked this route and consequently had a longer minimum mean residence time than those, which did not. It has also been shown that the spacing between the carbon bed and the canister rear wall had a large impact on both residence time and pressure drop. In cases where the carbon backed directly onto the canister rear wall flow in the axial direction from the outside wall toward the canister axis resulted in far greater pressure drop and a reduction in minimum mean residence time within the carbon bed.  相似文献   
7.
目的以机油为分散剂高温热解人发后发现新型纳米碳点,通过动物实验评价了该碳点的生物效应。方法利用高温热解法对人发和机油进行炭化,对炭化产物进行萃取、过滤分离和透析得到一种具有水溶性的新型物质碳点,并命名为JYRF-CDs。利用透射电子显微镜(TEM)、高分辨透射电子显微镜(HR-TEM)、紫外-可见分光光谱、傅里叶变换红外光谱、荧光光谱、X射线光电子能谱分析(XPS)等多种方法对JYRF-CDs进行表征,利用小鼠单核巨噬细胞RAW264.7细胞进行CCK-8毒性实验来评价JYRF-CDs的安全性,并通过小鼠耳肿胀实验和小鼠醋酸扭体实验对JYRF-CDs的生物效应进行评价。结果 JYRF-CDs外形为类球形,粒径均匀分布在1.8~3.6 nm,晶格间距为0.219 7 nm。细胞毒性实验结果显示,JYRF-CDs具有低毒性,动物实验结果表明JYRF-CDs具有良好的抗炎和镇痛作用。结论首次以机油为分散剂高温热解人发后发现一种全新的碳点JYRF-CDs,以JYRF-CDs为突破口,更加明确阐释以机油为分散剂高温热解人发后炭化产物具有生物效应的物质基础,为纳米类成分的研究提供了一种新方法。  相似文献   
8.
《L'Encéphale》2019,45(6):482-487
ObjectiveAntipsychotics are the standard treatment for psychosis. However, when combined with other lifestyle factors they are partially responsible for an excessive mortality rate. A clinical and paraclinical monitoring of patients is therefore necessary. In 2011, this element led doctors and pharmacists to improve monitoring and formalize a follow-up adapted to inmate patients. The aim of this study was to assess the impact of medical-pharmaceutical collaboration on monitoring quality of patients treated by antipsychotics.MethodsThis is a retrospective study including all patients treated by antipsychotics for at least 6 months in 2011 and again in 2015. Data were collected from medical files. The indicator assessing the monitoring quality was the compliance percentage, of registred parameters for each patient on the basis of specific guidelines.ResultsIn 2015 compared to 2011, the monitoring quality increased for 9 out of 10 parameters. This improvement was statisticaly significant for 7 of them : Body Mass Index, lipid test, complete blood count, transaminase, ionogram, glycemia, glomerular filtration rate.ConclusionThe actions of improvement collectivelly implemented in 2011 had a concrete impact on patients in the follow-up in 2015.  相似文献   
9.
BackgroundMelanocytes are derived from neural crest, and various pigmentary disorders may accompany abnormalities in nerve system or develop following dermatome, suggesting that melanocyte and pigmentation may be closely related to neural factors. There are reports of Becker''s nevus (BN) showing linear and segmental configuration, suggesting the association of BN with nerve system. However, there are no studies regarding the expression of neuropeptides in BN.ObjectiveWe investigated the expression of neuropeptides and innervation in BN.MethodsPolymerase chain reaction (PCR) array of 84 genes related to neuronal process was done. Among the genes with 10-fold or more increase in lesional, real-time PCR was performed for neuropeptide Y (NPY), galanin, neurotensin (NTS) and their receptors skin compared to normal skin. IHC stain was done to look for the expression of NPY, galanin, NTS and their receptors and the distribution of protein gene products (PGP) 9.5 immunoreactive nerve fibers.ResultsPCR array revealed that 16 out of 84 genes related to neuronal process were increased by 10-fold or more in lesional skin. In real-time PCR of NPY, galanin, NTS and their receptors, statistically significant increase of NPY1R (p<0.05) and marginally significant increase of NPY2R, GAL2R, and NTS2R (p<0.1) was verified in lesional skin. In immunohistochemistry, NPY, NPY1R NPY2R, and NTS2R were highly expressed in lesional skin and increased PGP 9.5 immunoreactive linear nerve fibers were found in the epidermis of BN.ConclusionNPY, galanin, NTS and their receptors and increased innervation may play a role in the pathogenesis of BN.  相似文献   
10.
Injection site reactions (ISRs) are a local phenomenon defined as a constellation of symptoms, including swelling, erythema, pruritus, and pain around the site of injection. This article reviews the different aspects of ISRs, including their epidemiology and pathogenesis, and provides practical guidance to diagnose and treat such reactions. More focus is given to food and drug administration (FDA)‐approved biological agents and biosimilars, which are licensed mainly for the treatment of dermatological conditions, including psoriasis, atopic dermatitis, and chronic urticaria. ISRs are major complications of all FDA‐approved self‐injectable biological agents, both in adults and children, with studies showing an incidence rate of 0.5–40%. The article emphasizes that ISRs are not correlated with drug efficacy or development of antidrug antibodies. Therefore, misunderstanding of the pathophysiology of the ISRs, most of them not being allergic or immunogenic reactions, might result in unnecessary discontinuation of the treatment. Almost all local reactions to subcutaneously administered biological agents can be prevented by changing the injection techniques, patient education, and training.  相似文献   
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