A myocardial patch made of collagen membranes loaded with collagen-binding human vascular endothelial growth factor accelerates healing of the injured rabbit heart

Tissue-engineered myocardial patches could be useful in the repair of myocardial injuries. The aim of the present study was to evaluate a collagen targeting delivery system for myocardial repair. A specific peptide collagen-binding domain (CBD) was fused to human vascular endothelial growth factor (VEGF) to enhance the binding of VEGF to collagen. In this study, collagen membranes loaded with CBD-VEGF, natural VEGF, or phosphate-buffered saline are used as cardiac patches to repair the infarcted myocardium in a rabbit model. CBD-VEGF/collagen group could effectively induce more cells to penetrate into the collagen membrane after 4 weeks and promote more vascularization in infarcted myocardium after 12 weeks compared with the other two control groups. Echocardiography and hemodynamic studies both show cardiac function improvement in the CBD-VEGF/collagen group. These results reveal that implantation of CBD-VEGF collagen membrane patch into the infarcted myocardium could effectively improve left ventricle cardiac function and increase the vascular density.     

MicroRNA regulation associated chondrogenesis of mouse MSCs grown on polyhydroxyalkanoates

Microbial polyhydroxyalkanoates (PHA) including poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) were found to induce chondrogenesis of mesenchymal stem cells (MSCs) and preserve chondrocytic phenotype as well as support chondrocytes-specific extracellular matrix (ECM) secretion. In this study, mouse MSCs cultured on the PHBHHx films for 24?h showed up-regulated expression of chondrogenic marker genes including aggrecan, col2, sox9, col10 and pthrp. To further illustrate this phenomonon, chondrogenesis-related microRNA expression profiling was examined by quantitative real-time PCR (RT-PCR) based on results of microRNA array obtained from comparison between mouse MSCs and mature mouse chondrocytes. Among 44 microRNAs related to chondrogenesis on microrray studies, considering only broadly-conserved microRNAs, seven differentially-expressed microRNAs were selected to study their target genes related to chondrogenesis. Two microRNAs out of the seven, namely, miR-29a and miR-29b, were revealed to directly target 3' UTR of col2a1 encoding type II collagen by dual-luciferase assay, and their activity was under the regulation of Sox9, the SRY-related high mobility group-box gene 9. For the first time microRNAs were shown to regulate the stem cell differentiation processes mediated by cell-material interactions.     

Pyrrolidine dithiocarbamate inhibits nuclear factor-κB pathway activation, and regulates adhesion, migration, invasion and apoptosis of endometriotic stromal cells

The activation of nuclear factor-κB (NF-κB) has been implicated in the development and progression of endometriosis. The aim of this study is to investigate the potential application of pyrrolidine dithiocarbamate (PDTC), a potent NF-κB inhibitor, in the treatment of endometriosis. NF-κB-DNA-binding activity, IκB phosphorylation and expression of nuclear p65 protein in endometriotic ectopic stromal cells (EcSCs), endometriotic eutopic stromal cells (EuSCs) and normal endometrial stromal cells (NESCs) were detected by electrophoretic mobility shift assay and western blot analysis. Adhesion, migration, invasion and apoptosis of EcSCs were observed by means of adhesion, migration, invasion and terminal deoxynucleotidyl transferase-mediated dUDP nick-end labeling assay, respectively. Gene and protein expressions of CD44s, matrix metalloproteinase (MMP)-2, MMP-9 and survivin in EcSCs were measured by RT-PCR and western blot analysis. The results showed that PDTC in the absence or presence of interleukin (IL)-1β showed stronger inhibitory effects on NF-κB-DNA-binding activity, IκB phosphorylation and expression of nuclear p65 protein in EcSCs than those in EuSCs or NESCs. PDTC enhanced apoptosis, and suppressed IL-1β-induced cellular adhesion, migration and invasion of EcSCs. Pretreatment of EcSCs with PDTC attenuated IL-1β-induced expressions of CD44s, MMP-2, MMP-9 and survivin at gene and protein levels. All these findings suggest that PDTC induces apoptosis and down-regulates adhesion, migration and invasion of EcSCs through the suppression of various molecules. Therefore, PDTC could be used as a therapeutic agent for the treatment of endometriosis.     

Biocompatible Poly(D,L‐lactide)‐block‐Poly(2‐methacryloyloxyethylphosphorylcholine) Micelles for Drug Delivery

Well‐defined amphiphilic PLA‐b‐PMPC diblock copolymers were synthesized. Bimimetic micelles were prepared and applied for release of anti‐cancer drugs (DOX). TEM and DLS analysis revealed a regular spherical shape with small diameter (less than 50 nm) of the micelle. The biocompatibility of PLA‐b‐PMPC micelles was studied, and it was found that the micelles possessed excellent cytocompatibility due to the zwitterionic phosphorylcholine group. DOX could be efficiently loaded into the micelles with a loading efficiency of 44–67%. The DOX‐loaded micelles showed lower cytotoxicity than free drugs and efficiently delivered and released the drug into cancer cells. With these properties, the PLA‐b‐PMPC polymer micelles are attractive as drug carriers for pharmaceutical application.

     

神经丛蛋白A2(PLXNA2)基因多态性与精神分裂症的关联研究

目的:探讨神经丛蛋白(PLXNA2)基因与汉族人群精神分裂症的关联。方法:采用DNA测序检测方法,依据ICD-10诊断标准,在735例汉族精神分裂症住院患者和1316例年龄、性别匹配的正常对照者中,探索PLXNA2基因5个单核苷酸多态性(SNP)位点与精神分裂症的关联。结果:PLXNA2基因的4个SNPs位点与精神分裂症关联(均P<0.05);由rs3811383-rs841865-rs2785622组成的单体型ATT及由rs841865-rs752016组成的单体型AC与精神分裂症关联(均P<0.05)。结论:本研究结果提示PLXNA2基因多态性在中国汉族人群中与精神分裂症关联。     

肝细胞肝癌组织浸润性淋巴细胞及其因子的表达

目的:分析原发性肝细胞癌(HCC)组织中浸润淋巴细胞的分类及细胞因子表达,探讨肝癌组织免疫微环境改变的意义.方法:收集76例原发性HCC的癌组织及非癌组织标本,应用流式细胞术及免疫组化的方法分别检测组织中免疫细胞的比例;运用流式微球阵列法(CBA)检测HCC组织和非癌组织中Th1/Th2类细胞因子,ELISA法检测TGF-1、VEGF的表达.结果:HCC患者中CD3+T细胞、CD4+ Th细胞、Treg细胞及CD455RO+记忆性T细胞在癌组织中的比例均高于相应的非癌组织,而CD8+ CTL细胞在癌组织中的比例较低;Treg细胞与Th细胞或CTL细胞水平呈负相关;癌组织中早期活化因子CD69在CD3+T淋巴细胞及NK细胞上的表达均低于非癌组织,而癌组织中晚期活化因子HLA-DR在CD3+T细胞表达的水平高于非癌组织.细胞因子IL-10、TGF-1及VEGF在癌组织中表达高于非癌组织.结论:肝癌组织微环境中,抗肿瘤效应性细胞比例下降,而抑制性细胞及其相关因子增加,引发肿瘤浸润淋巴细胞的免疫无能,导致肿瘤发生.     

颈动脉肿瘤术前大脑Willis环状况判定的临床研究

目的:探讨颈动脉瘤和颈动脉体瘤手术治疗前大脑Willis动脉环侧支循环状况判定的方法和标准,评价DSA全脑血管造影方法判定一侧颈动脉(颈内动脉)术中永久性阻断的安全性.方法:本组颈动脉瘤和颈动脉体瘤患者共14例,均行CT平扫、CT增强扫描和CTA血管成像三维重建,9例行DSA全脑血管造影检查.8例行手术治疗,3例保留颈总动脉和颈内动脉剥除肿瘤、5例颈总动脉(颈内动脉)连同肿瘤一并切除;4例术中同步行脑电图监测.分析术前颈动脉压迫训练后DSA全脑血管造影、术中脑电图监测等方法评价大脑侧支循环的可行性和可靠性.结果:8例手术患者中,无死亡病例,切口均一期愈合.术后均获随访3月～5 a,肿瘤相关症状消失,无肿瘤复发,其中1例术后出现偏瘫、失语,半年后康复.结论:DSA全脑血管造影检查是颈动脉肿瘤术前判断大脑Willis环侧支循环状况的重要方法,但不能作为判定一侧颈动脉结扎、切除安全性的"金标准".     

Failure analysis of the fractured wires in sternal perichronal loops

We report failure analysis of sternal wires in two cases in which a perichronal fixation technique was used to close the sternotomy. Various characteristics of the retrieved wires were compared to those of unused wires of the same grade and same manufacturer and with surgical wire specifications. In both cases, wire fracture was un-branched and transgranular and proceeded by a high cycle fatigue process, apparently in the absence of corrosion. However, stress anlysis indicates that the effective stress produced during strong coughing is lower than the yield strength. Our findings suggest that in order to reduce the risk for sternal dehiscence, the diameter of the wire used should be increased.     

全关节镜下改良Broström术治疗慢性踝关节外侧不稳的临床疗效观察

目的 探讨全关节镜下改良Broström术治疗慢性踝关节外侧不稳的临床疗效。方法 回顾性研究。纳入2016年1月—2018年6月徐州市中心医院慢性踝关节外侧不稳患者33例(33侧),其中男20例、女13例,年龄16～55(30.3±5.7)岁;右侧22例,左侧11例。病程12~48(25.6±14.2)个月。受伤原因:扭伤28例,车祸伤5例。所有患者进行全关节镜下的改良Broström手术。术后定期随访,观察患者伤口愈合情况,并发症发生情况,观察踝关节活动情况,踝关节内翻应力试验、踝关节前抽屉试验检查踝关节稳定情况及步态。术后12个月采用疼痛视觉模拟评分法(VAS)评价踝关节疼痛情况,采用美国足踝外科协会(AOFAS)踝与后足评分和Karlsson 踝关节功能评分(KAFS)评价踝关节功能。对比患者手术前与术后12个月VAS、AOFAS、KAFS评分改善情况。结果 33例患者均顺利完成手术,手术时间35～80(50.3±12.6)min。术后患者切口均一期愈合,未出现伤口感染、神经损伤、血管损伤、肌腱损伤等并发症。33例患者均获得随访,随访时间12～40(25.0±10.7)个月。末次随访时,患者均无置入物排斥反应或线结反应;踝关节疼痛完全消失,关节活动度良好;踝关节内翻应力试验、踝关节前抽屉试验均阴性,未出现踝关节外侧不稳定,患者均恢复正常步态。术后12个月依据AOFAS评分标准,踝关节功能优27例、良6例;依据KAFS评分标准,踝关节功能优28例、良5例。术后12个月VAS评分由术前(6.02±1.93)分降低到(1.33±0.16)分,AOFAS评分由术前(61.75±13.08)分提高到(92.37±4.15)分,KAFS评分由术前(64.46±10.81)分提高到(93.19±5.58)分,差异均有统计学意义(t=12.765, -13.303, -12.346, P值均＜0.05)。结论 全关节镜下改良Broström术,手术创伤小,是一种治疗慢性踝关节外侧不稳的有效方法。     

腹主动脉瘤开放手术和腔内手术治疗的近期疗效分析

目的 对比分析腹主动脉瘤开放手术(OSR)与腔内修复手术(EVAR)的近期疗效。方法 回顾性研究。纳入2008年1月—2020年12月蚌埠医学院第一附属医院血管外科接受手术治疗的腹主动脉瘤患者118例,其中男102例、女16例,年龄(70.5±9.6)岁。根据手术治疗方式的不同,分为OSR组23例和EVAR组95例。观察指标:(1)比较两组患者的年龄、性别、不良生活习惯、合并症、瘤体最大径、复杂瘤颈形态等基线资料。(2)比较两组患者手术时间、术中出血量、术后禁饮食时间、术后卧床时间、住院时间,以及术后并发症和死亡发生情况。(3)术后定期复查CT血管成像(CTA),观察有无再干预、支架内血栓形成、支架内再狭窄、移植物感染、各型内漏等发生。结果 OSR组和EVAR组的基线资料比较差异均无统计学意义(P值均＞0.05)。患者均顺利完成手术。EVAR组的手术时间、术中出血量、术后禁饮食时间、术后卧床时间、住院时间均少于OSR组,分别为(141.15±22.97) min与(242.79±29.41) min、(34.32±16.08) mL与(443.93±109.58)mL、(14.26±3.34) h与(52.25±12.05)h、(4.07±0.63) d与(6.48±0.83)d、(21.88±1.78) d与(24.44±2.44)d,差异均有统计学意义(t=17.919、17.881、14.978、15.532、4.745,P值均＜0.05);两组患者围手术期并发症发生率及死亡率比较,差异均无统计学意义(P值均＞0.05)。患者均获随访1年,除EVAR组2例出现轻微Ⅱ型内漏外,均无严重并发症发生。结论 腹主动脉瘤的OSR和EVAR均能取得良好的近期治疗效果。与OSR相比较,EVAR手术时间更短,术中出血更少,术后禁饮食、卧床及住院时间更短,术后恢复更快。