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21.
目的 对比研究朝鲜淫羊藿酸性多糖酯化还原前后的理化特性,并探讨其改善油酸诱导的肝癌HepG2细胞脂质堆积活性的差异。方法 采用高效凝胶渗透色谱法测定朝鲜淫羊藿酸性多糖(EFPA)的均一性和分子量,高效液相色谱法测定EFPA和酯化还原后朝鲜淫羊藿酸性多糖(EFPA-R)的单糖组成;采用油酸(OA)处理HepG2细胞诱导建立脂质蓄积模型,不同浓度EFPA与EFPA-R(10、30、100、300 μg·mL-1)分别和OA共同作用于细胞24 h,采用CCK-8试剂盒测定细胞存活率,油红O染色观察细胞内脂滴蓄积情况,并采用试剂盒测定细胞内总胆固醇(TC)、甘油三酯(TG)含量。结果 EFPA为成分均一的多糖组分,分子量为125.8 kDa,由甘露糖、葡萄糖、半乳糖、葡萄糖醛酸和阿拉伯糖组成,摩尔比为1.7∶7.4∶1.4∶1.8∶1.0,葡萄糖占比最大,EFPA-R由甘露糖、葡萄糖、半乳糖和阿拉伯糖组成,摩尔比为0.8∶10.6∶2.1∶1.0;在10-300 μg·mL-1范围内,EFPA和EFPA-R对HepG2细胞的抑制作用较弱,作为给药浓度;与空白组相比,模型组细胞中TC、TG含量显著升高(P < 0.01),细胞内红色脂滴显著增多,与模型组相比,EFPA可显著降低细胞中TC、TG含量(P < 0.01),明显减少细胞内红色脂滴(P < 0.05或P < 0.01),EFPA-R干预后细胞则无明显变化。结论 EFPA可明显改善HepG2细胞脂质堆积情况,且呈现剂量依赖性,而半乳糖醛酸(GalA)的存在可能是其抑制HepG2细胞脂质蓄积的关键因素。 相似文献
22.
外泌体是一类直径为30~100 nm的圆盘囊泡,其内包含许多组分,诸如复杂RNA和蛋白质等,主要参与细胞间的信号转导。肿瘤相关巨噬细胞(tumor-associated macrophages,TAMs)是肿瘤微环境中普遍存在的巨噬细胞,通过对肿瘤生长、免疫逃逸、侵袭和转移、耐药性等多方面的作用影响肿瘤进程。外泌体在肿瘤相关巨噬细胞的招募、极化及抗肿瘤免疫调控等方面发挥着重要的调节功能。同时,TAMs以外泌体为媒介作用于肿瘤细胞,从而构成了外泌体、TAMs与肿瘤细胞之间相互作用的调控通路。综上所述,本文旨在阐明肿瘤细胞与TAMs之间,以外泌体为“桥梁”相互影响的潜在机制,以及靶向肿瘤细胞和TAMs来源的外泌体在恶性肿瘤治疗中的展望。 相似文献
23.
《介入医学杂志(英文)》2022,5(4):196-199
ObjectiveThis study aimed to analyze and evaluate the results of mid-term follow-up after fetal pulmonary valvuloplasty (FPV) in fetuses with pulmonary atresia with intact ventricular septum (PA/IVS).MethodsFrom August 31, 2018, to May 31, 2019, seven fetuses with PA/IVS and hypoplastic right heart were included in this study. All underwent echocardiography by the same specialist and were operated on by the same team. Intervention and echocardiography data were collected, and changes in the associated indices noted during follow-up were analyzed.ResultsAll seven fetuses successfully underwent FPV. The median gestational age at FPV was 27.54 weeks. The average FPV procedural time was 6 ?min. Persistent bradycardia requiring treatment occurred in 4/7 procedures. Finally, five pregnancies were successfully delivered, and the other two were aborted. Compared to data before fetal cardiac interventions (FCI), tricuspid valve annulus diameter/mitral valve annulus diameter (TV/MV) and right ventricle diameter/left ventricle diameter (RV/LV) of all fetuses had progressively improved. The maximum tricuspid regurgitation velocity decreased from 4.60 ?m/s to 3.64 ?m/s. The average follow-up time was 30.40 ?± ?2.05 months. During the follow-up period, the diameter of the tricuspid valve ring in five children continued to improve, and the development rate of the tricuspid valve was relatively obvious from 6 months to 1 year after birth. However, the development of the right ventricle after birth was relatively slow. It was discovered that there were individual variations in the development of the right ventricle during follow-up.ConclusionThe findings support the potential for the development of the right ventricle and tricuspid valve in fetuses with PA/IVS who underwent FCI. Development of the right ventricle and tricuspid valve does not occur synchronously during pregnancy. The right ventricle develops rapidly in utero, but the development of tricuspid valve is more apparent after birth than in utero. 相似文献
24.
王志敏 《中国工业医学杂志》2022,35(5):463-465
[摘要]?目的?探讨GeneXpert MTB/RIF检测技术在肺结核诊断中的应用价值。方法?以2020年7月—2021年6月在天门市第一人民医院治疗的疑似肺结核患者107例作为研究对象,所有患者均留取痰标本,进行痰涂片、痰培养、GeneXpert MTB/RIF检测、比例法药敏试验。以培养法和比例法药敏结果为金标准,计算GeneXpert MTB/RIF检测结核分枝杆菌(Mycobacterium tuberculosis,MTB)及其对于利福平耐药性检测的灵敏度、特异度、与金标准的的一致率。结果?107例疑似肺结核患者中,痰涂片阳性39例(36.45%),涂片阴性68例(63.55%)。以痰培养结果为金标准,GeneXpert MTB/RIF检测TBM的灵敏度为85.42%(41/48),特异度为88.14%(52/59)。GeneXpert MTB/RIF与痰培养诊断一致率为86.92%(93/107);进一步分析,GeneXpert MTB/RIF检测痰涂片阳性患者MTB的灵敏度为97.22%(35/36),特异度为33.33%(1/3),检测涂片阴性患者MTB的灵敏度为50.00%(6/12),特异度为91.07%(51/56)。以比例法药敏结果为金标准,确认痰培养阳性36例患者中利福平耐药有4例(11.11%),敏感的有32例(88.89%);GeneXpert MTB/RIF检测痰培养阳性患者利福平耐药的灵敏度为75.00%(3/4),特异度为93.75%(30/32)。GeneXpert MTB/RIF与比例法药敏试验一致率为91.67%。结论?GeneXpert MTB/RIF检测技术对于肺结核诊断以及利福平的耐药分析具有重要实用价值,可以作为金标准。 相似文献
25.
Diabetic foot ulcer is a devastating complication of diabetes mellitus and significant cause of mortality and morbidity all over the world and can be complex and costly. The development of foot ulcer in a diabetic patient has been estimated to be 19%-34% through their lifetime. The pathophysiology of diabetic foot ulcer consist of neuropathy, trauma and, in many patients, additional peripheral arterial disease. In particular, diabetic neuropathy leads to foot deformity, callus formation, and insensitivity to trauma or pressure. The standard algorithms in diabetic foot ulcer management include assessing the ulcer grade classification, surgical debridement, dressing to facilitate wound healing, off-loading, vascular assessment (status and presence of a chance for interventional vascular correction), and infection and glycemic control. Although especially surgical procedures are sometimes inevitable, they are poor predictive factors for the prognosis of diabetic foot ulcer. Different novel treatment modalities such as nonsurgical debridement agents, oxygen therapies, and negative pressure wound therapy, topical drugs, cellular bioproducts, human growth factors, energy-based therapies, and systematic therapies have been available for patients with diabetic foot ulcer. However, it is uncertain whether they are effective in terms of promoting wound healing related with a limited number of randomized controlled trials. This review aims at evaluating diabetic foot ulcer with regard to all aspects. We will also focus on conventional and novel adjunctive therapy in diabetic foot management. 相似文献
26.
27.
目的:本研究通过检测前列腺特异性膜抗原(prostate specific membrane antigen,PSMA)-肿瘤特异性嵌合抗原受体(chimeric antigen receptor,CAR)-细胞因子诱导的杀伤细胞(cytokine induced killer cell,CIK)转基因细胞杀伤三种前列腺癌细胞株的效率,鉴定其用于后期治疗前列腺癌的可行性。方法:通过已经构建的二代PSMA-CAR慢病毒表达载体转染CIK细胞,构建PSMA-CAR-CIK转基因细胞;通过CCK8法检测CIK细胞及PSMA-CAR-CIK转基因细胞杀伤三种前列腺癌细胞株PC3、LNCaP、DU145的效率及效靶比。结果:转基因PSMA-CAR-CIK细胞构建成功;3 h~3.5 h为检测效应细胞对靶细胞细胞毒活性时与CCK8试剂孵育的最佳时间;两种效应细胞均在效靶比为10∶1、15∶1、20∶1时,杀伤率逐步增高,无统计学意义(P>0.05),但与其它组相比差异显著(P<0.05)。结论:两种效应细胞对于前列腺癌细胞的杀伤,只要效靶比达到10∶1的比例,就能起到一个较好的杀瘤效果,并且随着效应细胞的增加,其抗肿瘤能力逐步加强;转基因PSMA-CAR-CIK细胞的构建为CAR技术治疗前列腺癌的临床应用奠定了基础。 相似文献
28.
《Dental materials》2022,38(8):1283-1300
ObjectivesTo compare new bone formation in mandibular critical-sized bone defects (CSBDs) in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats filled with bioceramics (BCs) with or without bone marrow mesenchymal stem cells (BMSCs).MethodsA total of 64 adult female Sprague-Dawley rats were randomized into four groups (n = 16 per group): Group 1 healthy, Group 2 diabetic, Group 3 osteoporotic, and Group 4 diabetic-osteoporotic rats. Streptozotocin was used to induce type 1 diabetes in Group 2 and 4, while bilateral ovariectomy was used to induce osteoporosis in Group 3 and 4. The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxypatatite 60% and β-tricalcium phosphate 40%) alone and eight with BMSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2).ResultsIn all groups (healthy, diabetics, osteoporotics, and diabetics-osteoporotics), the CSBDs filled with BC + BMSCs showed greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with CSBDs treated with BC alone (at 4 and 8 weeks).ConclusionsApplication of BMSCs cultured on BCs improves bone regeneration in CSBDs compared with application of BCs alone in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats. 相似文献
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