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31.
Introduction:Knee osteoarthritis is a common condition that affects daily functioning and decreases the quality of life. There are many ways of treatment depending on the stage of the disease. Advanced cases are qualified for arthroplasty, which is an extensive and demanding surgical procedure. Less advanced stages are treated in various ways: from rehabilitation, through oral and intra-articular pharmacotherapy, to surgical treatment (arthroscopy, osteotomy). Because surgical treatment is risky, scientists focus on less invasive therapeutic methods. The most valuable management is based on regeneration. Mesenchymal stromal cells (MSC) derived from the adipose tissue have a great regenerative and anti-inflammatory potential, therefore an attempt is being made to take advantage of them in knee osteoarthritis treatment.The study aims to compare the clinical effects of treatment of knee osteoarthritis using adipose tissue MSC obtained by an enzymatic method with the outcomes of the therapy with the mechanically fragmented adipose tissue.Methods:One hundred adults with primary knee osteoarthritis will undergo lipoaspiration under sterile conditions. The collected lipoaspirates will be further processed, depending on the randomly assigned group-enzymatically with the use of collagenase or mechanically using the Lipogems system. The preparations will be administered to the patients’ knee joints in the operating room under ultrasound control.The results of treatment will be assessed using Knee Injury and Osteoarthritis Outcome Score, measuring the flexibility of the knee joint, evaluating joint gap in X-ray and the quality of cartilage in magnetic resonance T2-mapping during 1 year after treatment.Discussion/conclusion:Identification and functional analysis of the regenerative capacity of adipose-derived MSC depending on three variables (body weight, sex, and age) will help to develop a targeted therapy for different groups of patients and will determine the effectiveness of both methods of treatment. An attempt will be made to identify groups of patients with the greatest regenerative potential of the adipose tissue, and thus indicate those with the most probable improvement of the joint condition.Trial registration:This study protocol has been approved by the Ethics Committee of Medical University of Warsaw and registered on www.clinicaltrials.gov: NCT04675359 (06 Jan 2021)  相似文献   
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With the advance of genome engineering technology, chimeric antigen receptors (CARs)-based immunotherapy has become an emerging therapeutic strategy for tumors. Although initially designed for T cells in tumor immunotherapy, CARs have been exploited to modify the function of natural killer (NK) cells against a variety of tumors, including hepatocellular carcinoma (HCC). CAR-NK cells have the potential to sufficiently kill tumor antigen-expressing HCC cells, independent of major histocompatibility complex matching or prior priming. In this review, we summarize the recent advances in genetic engineering of CAR-NK cells against HCC and discuss the current challenges and prospects of CAR-NK cells as a revolutionary cellular immunotherapy against HCC.  相似文献   
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《Vaccine》2021,39(45):6601-6613
AKS-452 is a biologically-engineered vaccine comprising an Fc fusion protein of the SARS-CoV-2 viral spike protein receptor binding domain antigen (Ag) and human IgG1 Fc (SP/RBD-Fc) in clinical development for the induction and augmentation of neutralizing IgG titers against SARS-CoV-2 viral infection to address the COVID-19 pandemic. The Fc moiety is designed to enhance immunogenicity by increasing uptake via Fc-receptors (FcγR) on Ag-presenting cells (APCs) and prolonging exposure due to neonatal Fc receptor (FcRn) recycling. AKS-452 induced approximately 20-fold greater neutralizing IgG titers in mice relative to those induced by SP/RBD without the Fc moiety and induced comparable long-term neutralizing titers with a single dose vs. two doses. To further enhance immunogenicity, AKS-452 was evaluated in formulations containing a panel of adjuvants in which the water-in-oil adjuvant, Montanide™ ISA 720, enhanced neutralizing IgG titers by approximately 7-fold after one and two doses in mice, including the neutralization of live SARS-CoV-2 virus infection of VERO-E6 cells. Furthermore, ISA 720-adjuvanted AKS-452 was immunogenic in rabbits and non-human primates (NHPs) and protected from infection and clinical symptoms with live SARS-CoV-2 virus in NHPs (USA-WA1/2020 viral strain) and the K18 human ACE2-trangenic (K18-huACE2-Tg) mouse (South African B.1.351 viral variant). These preclinical studies support the initiation of Phase I clinical studies with adjuvanted AKS-452 with the expectation that this room-temperature stable, Fc-fusion subunit vaccine can be rapidly and inexpensively manufactured to provide billions of doses per year especially in regions where the cold-chain is difficult to maintain.  相似文献   
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目的:探讨溴结构域和超末端结构域(bromodomain and extra terminal domain,BET)抑制剂对弥漫性大B细胞淋巴瘤CRL-2630细胞生长的影响,以及对弥漫性大B细胞淋巴瘤BALB/c-nu裸鼠外周血中辅助性T细胞17(helper T cells,Th17)数量和相关细胞因子表达的影响。方法:培养弥漫性大B细胞淋巴瘤株CRL-2630,使用不同浓度BET抑制剂(2、4、8、16、32 nmol/L)处理48 h,32 nmol/L BET抑制剂处理不同时间(12、24、36、48 h),CCK-8法检测各处理细胞活性;集落形成实验检测不同BET抑制剂浓度处理后细胞集落形成能力;Annexin V-FITC/PI双染法检测不同BET抑制剂浓度处理后细胞凋亡情况;实时荧光定量PCR与Western blot检测32 nmol/L BET抑制剂处理CRL-2630细胞48 h后HMGA1 mRNA与蛋白的表达水平;构建HMGA1过表达载体并通过脂质体介导法转染CRL-2630细胞,并用32 nmol/L BET抑制剂处理48 h,检测细胞活性与凋亡情况;构建裸鼠弥漫性大B细胞淋巴瘤模型并采集外周血,流式细胞术检测Th17细胞比例,ELISA法检测相关细胞因子的含量。结果:在一定范围内,BET抑制剂呈剂量依赖性地抑制CRL-2630细胞的活性,32 nmol/L BET抑制剂以时间依赖性地抑制CRL-2630细胞的活性。随着BET抑制剂处理浓度的增高,CRL-2630细胞集落形成能力逐渐下降,凋亡率逐渐升高。32 nmol/L BET抑制剂处理CRL-2630细胞48 h后,细胞中HMGA1的mRNA和蛋白水平均明显下降。pcDNA3.4-HMGA1转染CRL-2630细胞再使用BET抑制剂处理后,细胞的活性升高而凋亡率明显下降。弥漫性大B细胞淋巴瘤裸鼠经BET抑制剂作用后,外周血Th17细胞比例和IL-6、IL-17、IL-23含量较生理盐水组明显下降。结论:BET抑制剂能有效抑制 CRL-2630细胞活性,并诱导其凋亡,在一定范围内呈时效和量效关系。BET抑制剂还可以抑制弥漫性大B细胞淋巴瘤裸鼠外周血Th17细胞数量和相关细胞炎性因子的分泌,其作用机制可能与HMGA1的表达下调有关。  相似文献   
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韦斌  连浩  邓彦  孙园园 《国际眼科杂志》2022,22(12):1960-1964

目的:评估飞秒激光辅助超声乳化联合Ahmed青光眼引流阀植入术治疗合并难治性青光眼的白内障的有效性和安全性。

方法:回顾性病例对照研究。2019-10/2021-10入院合并难治性青光眼的白内障患者53例53眼,依据自愿选择分为飞秒激光辅助白内障超声乳化(FLACS)组26例26眼和常规白内障超声乳化(CPCS)组27例27眼。两组分别行FLACS和CPCS联合Ahmed青光眼引流阀植入术。比较两组患者术中超声乳化能量释放量(CDE)、有效超声时间(EPT)的差异和术前与术后抗青光眼药物数量的变化,以及术后观察不同时期(1d,1wk,1、3mo)在提高最佳矫正视力(BCVA),降低眼压、角膜内皮细胞损伤程度和手术并发症及成功率状况。

结果:FLACS组术中CDE和EPT明显低于CPCS组(t=8.50、5.16; P<0.01、=0.001)。两组术后抗青光眼药物较术前均明显减少(t=9.12、7.76; P=0.011、0.016),但两组间无差异(t=1.79,P=0.082)。两组术后BCVA均较术前改善,眼压均较术前降低(P<0.05)。FLACS组在术后早期(1d,1wk)BCVA的改善较CPCS组更显著(t=9.74、8.49; P=0.008、0.012),但在术后1、3mo的BCVA改善程度并无不同(t=0.62、0.44; P=1.415、2.021)。CPCS组在术后随访不同时期的角膜内皮细胞损伤较FLACS组更明显(P<0.05)。术后随访的不同时期FLACS组和CPCS组在控制眼压方面无差异(F组间=0.64,P组间=0.421)。FLACS组的手术并发症发生率27%(7/26)较CPCS组89%(24/27)低(χ2=20.95,P<0.01),其中角膜水肿(8% vs 41%)、前囊撕裂(0 vs 11%)在FLACS组中明显低于CPCS组,后囊破裂(0 vs 7%)、玻璃体脱出(0 vs 4%)及人工晶状体偏位(0 vs 7%)也均发生在CPCS组。但两组的治疗总成功率相近(P=28.718)。

结论:飞秒激光辅助超声乳化联合Ahmed青光眼引流阀植入术可充分发挥联合手术的精准微创可控优势,帮助合并难治性青光眼的白内障患者有效降低眼压及更早获得视力恢复。  相似文献   

39.
组织工程技术通过利用支架材料、种子细胞、生长因子以达到修复或再生组织器官的目的。支架材料的作用是为种子细胞提供机械支撑并且保护细胞免受体内有害微环境的影响。因此,选择或制备适当的支架材料是组织工程中的关键一步。近年来,将支架材料和牙龈间充质干细胞(gingival mesenchymal stem cells,GMSCs)联合应用于组织工程的研究逐渐走向成熟。本文就组织工程中牙龈间充质干细胞递送支架载体的研究现状进行综述,以期为GMSCs组织工程递送支架载体材料的开发和选择提供思路。  相似文献   
40.
ObjectivesThe reduction of postoperative acute kidney injury in patients undergoing cardiopulmonary bypass surgery using an oxygen delivery-guided perfusion strategy (oxygen delivery strategy) for cardiopulmonary bypass management compared with a fixed flow perfusion (conventional strategy) remains controversial. The purpose of this study was to determine whether a oxygen delivery strategy would reduce the incidence of postoperative acute kidney injury in patients undergoing cardiopulmonary bypass surgery.MethodsWe randomly enrolled 300 patients undergoing cardiopulmonary bypass surgery. Patients were randomly assigned to a oxygen delivery strategy (maintaining a oxygen delivery index value >300 mL/min/m2 through pump flow adjustments during cardiopulmonary bypass) or a conventional strategy (a target pump flow was determined on the basis of the body surface area). The primary end point was the development of acute kidney injury. Secondary end points were the red blood cell transfusion rate and number of red blood cell units, intubation time, postoperative length of stay in the intensive care unit and the hospital, predischarge estimated glomerular filtration rate, and hospital mortality.ResultsAcute kidney injury occurred in 20 patients (14.6%) receiving the oxygen delivery strategy and in 42 patients (30.4%) receiving the conventional strategy (relative risk, 0.48; 95% confidence interval, 0.30-0.77; P = .002). The secondary end points were not significantly different between strategies. In a prespecified subgroup analysis of patients who had nadir hematocrit less than 23% or body surface area less than 1.40 m2, the oxygen delivery strategy seemed to be superior to the conventional strategy and the existence of quantitative interactions was suggested.ConclusionsAn oxygen delivery strategy for cardiopulmonary bypass management was superior to a conventional strategy with respect to preventing the development of acute kidney injury.  相似文献   
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