壳聚糖抗菌生物医用膜在烧伤创面中的临床应用

目的总结水溶性壳聚糖抗菌生物医用膜凝胶剂(商品名:凯舒林)对人体II度烧伤创面的治疗作用和安全性,并探索后期创面色素沉着、瘢痕增殖的机制。方法选择II度烧伤患者60例,用药前均用生理盐水清洁创面、去腐皮,于创面上均匀涂壳聚糖抗菌生物医用膜治疗,观察记录创面成痂、止痛、感染及痂下愈合时间,追踪随访6个月后创面色素沉着及瘢痕增殖程度。结果本组60例使用壳聚糖抗菌生物医用膜治疗的烧伤患者,创面全部自行愈合。治愈时间:浅Ⅱ度患者平均8.5 d;深Ⅱ度患者平均19 d。创面愈合后随访6个月,浅Ⅱ度创面患者3个月内有轻度色素改变,3个月后逐步恢复正常;深Ⅱ度创面患者3个月后部分患者有散在的点样色素脱失改变;部分患者有散在的扁平瘢痕。随访6个月,创面色素沉着和瘢痕增生程度明显减轻,功能明显改善,未见瘢痕疙瘩增殖。结论壳聚糖抗菌生物医用膜用于烧伤创面具有良好的组织相容性,止痛效果好,创面成痂快,兼有控制创面感染,促进愈合,减轻瘢痕增殖的作用,无明显不良反应,安全性好。     

SCAR is a primary regulator of Arp2/3-dependent morphological events in Drosophila

The Arp2/3 complex and its activators, Scar/WAVE and Wiskott-Aldrich Syndrome protein (WASp), promote actin polymerization in vitro and have been proposed to influence cell shape and motility in vivo. We demonstrate that the Drosophila Scar homologue, SCAR, localizes to actin-rich structures and is required for normal cell morphology in multiple cell types throughout development. In particular, SCAR function is essential for cytoplasmic organization in the blastoderm, axon development in the central nervous system, egg chamber structure during oogenesis, and adult eye morphology. Highly similar developmental requirements are found for subunits of the Arp2/3 complex. In the blastoderm, SCAR and Arp2/3 mutations result in a reduction in the amount of cortical filamentous actin and the disruption of dynamically regulated actin structures. Remarkably, the single Drosophila WASp homologue, Wasp, is largely dispensable for these numerous Arp2/3-dependent functions, whereas SCAR does not contribute to cell fate decisions in which Wasp and Arp2/3 play an essential role. These results identify SCAR as a major component of Arp2/3-dependent cell morphology during Drosophila development and demonstrate that the Arp2/3 complex can govern distinct cell biological events in response to SCAR and Wasp regulation.     

MRI在剖宫产术后瘢痕妊娠诊疗路径中的应用价值

摘要 目的：探讨磁共振成像在剖宫产术后瘢痕妊娠（cesarean scar pregnancy,CSP）诊疗路径中的应用价值。方法：回顾性分析24例经手术和（或）病理证实为瘢痕妊娠的孕妇临床和影像检查资料,记录MRI上妊娠囊位置、大小、T1、T2信号强度、妊娠囊类型、妊娠囊与子宫前壁下段肌层及膀胱的关系,分析MR特征对临床诊疗路径的应用价值。结果：24例妊娠囊均位于子宫下段,为圆形或卵圆形,11例妊娠囊为单纯囊性,12例妊娠囊为混杂包块型,1例因清宫术后行MR,未见明确妊娠囊,仅见子宫下段混杂信号。10例妊娠囊附着处子宫肌厚度不可测量,余14例妊娠囊附着处子宫肌厚度约0.9～5.0 mm,平均2.5±1.1 mm。据此,CSP分型为I型5例,II型7例,III型12例。结论：MRI能较好的评估CSP, 在CSP诊疗路径中的应用价值较大。     

Involvement of Arp2/3 complex in MCP-1-induced chemotaxis

The migrating monocyte shows dynamic actin polymerization in response to MCP-1. We investigated the involvement of the actin-related protein 2 and 3 complex (Arp2/3 complex) during chemotaxis of a human monocyte cell line (THP-1). To clarify whether the Arp2/3 complex directly polymerizes actin in response to MCP-1 stimulation, THP-1 cells were transfected with complementary DNA constructs encoding ScarWA. In ScarWA-transfected cells, neither recruitment of Arp2/3 complex at the leading edge nor actin polymerization was detected. Indeed, migration induced by MCP-1 was almost completely blocked. At the same time, transfection also interfered with the recruitment of integrin beta-1 at the leading edge and reduced affinity binding to fibronectin. Immunoprecipitation with an anti-Arp2 antibody showed that integrin beta-1 and WASP were co-precipitated under the condition of MCP-1 stimulation. These results indicate that interaction between the Arp2/3 complex and WASP stimulates actin polymerization and integrin beta-1-mediated adhesion during MCP-1-induced chemotaxis of THP-1 cells.     

胎盘间充质干细胞治疗小鼠烫伤愈合的相关研究

目的:观察胎盘间充质干细胞对TGF-β1/Smad信号通路的调控作用,探讨胎盘间充质干细胞对烫伤愈合及瘢痕形成的影响.方法:构建小鼠烫伤模型,注射人胎盘间充质干细胞(hPMSCs),荧光显微镜观察小鼠创伤皮肤组织中hPMSCs细胞的存活情况;HE和Masson染色观察小鼠创伤皮肤的变化;Western blot检测观察...     

miR-21在疤痕形成中的作用及其机制研究

目的:探究mi R-21在疤痕形成中的作用及其相关机制。方法:选取2016年3月-2017年8月在本院就诊的20例皮肤有疤痕患者,采集患者的正常皮肤组织(正常组)、疤痕组织(疤痕组),进行成纤维细胞的分离培养,比较正常组、疤痕组mi R-21与Smad-7的m RNA表达水平,并在疤痕组织加入mi R-21抑制剂(抑制组),比较三组成纤维细胞增殖情况、蛋白表达及磷酸化水平。结果:正常组中Smad-7的m RNA表达水平显著高于疤痕组,而mi R-21的m RNA水平显著低于疤痕组,差异均有统计学意义(P0.05)。细胞培养48 h和72 h时,疤痕组成纤维细胞增殖水平明显高于正常组和抑制组,差异有统计学意义(P0.05),而抑制组和正常组成纤维细胞增殖水平比较差异无统计学意义(P0.05)。疤痕组成纤维细胞Smad-7蛋白表达低于正常组和抑制组,差异有统计学意义(P0.05),疤痕组成纤维细胞Smad-2、Smad-3蛋白表达及磷酸化水平均高于正常组和抑制组,差异有统计学意义(P0.05)。结论:疤痕组织中mi R-21通过负调控Smad-7的表达,从而引起Smad-2与Smad-3蛋白表达发生变化,使得疤痕成纤维细胞的增殖水平明显增高,最终促成疤痕的形成。     

Control of the intracellular levels of prostaglandin E2 through inhibition of the 15-hydroxyprostaglandin dehydrogenase for wound healing

Excessive scar formation is an aberrant form of wound healing and is an indication of an exaggerated function of fibroblasts and excess accumulation of extracellular matrix during wound healing. Much experimental data suggests that prostaglandin E₂ (PGE₂) plays a role in the prevention of excessive scarring. However, it has a very short half-live in blood, its oxidization to 15-ketoprostaglandins is catalyzed by 15-hydroxyprostaglandin dehydrogenase (15-PGDH). Previously, we reported that 15-PGDH inhibitors significantly increased PGE₂ levels in A549 cells. In our continuing attempts to develop highly potent 15-PGDH inhibitors, we newly synthesized various thiazolidine-2,4-dione derivatives. Compound 27, 28, 29, and 30 demonstrated IC₅₀ values of 0.048, 0.020, 0.038 and 0.048 μM, respectively. They also increased levels of PGE₂ in A549 cells. Especially, compound 28 significantly increased level of PGE₂ at 260 pg/mL, which was approximately fivefold higher than that of control. Scratch wounds were analyzed in confluent monolayers of HaCaT cells. Cells exposed to compound 28 showed significantly improved wound healing with respect to control.     

The glucan-chitin complex in Saccharomyces cerevisiae

Scar rings (SR) from scarless cells at the early stages of budding and mature bud scars from Saccharomyces cerevisiae isolated by both chemical and enzymic treatment of cell walls were observed by selected-area electron diffraction (SAED), X-ray diffraction and electron microscopy with simultaneous physico-chemical characterization (including molar mass, intrinsic viscosity and crystallite size) of -chitin and glucan. The SR, composed of glucan with strong 0.608; 0.397 and 0.293 nm X-ray reflections, was formed at the start of budding. The SAED patterns of -chitin both in the adjacent circular zone and in the parts of newly formed primary septum (PS), observed when the development of the PS started, did not differ from those of -chitin in the single mature bud scar. The bud scar consisted of -chitin, glucan and mannan and their content, as well as the crystallite size of chitin, depended on the mode of preparation.Non-Standard Abbreviations ACZ Adjacent circular zone - BS Birth scar - CFW Calcofluor white M2R new: Disodium salt of 4,4-bis-(4-anilino-bis-diethyl-amino-S-triazine-2-yl-amino)-2,2-stilbene-disulfonic acid - EDI Electron dense istmus - PS Primary septum - SAED Selected area electron diffraction - SEM Scanning electron microscopy - SR Scar ring - TEM Transmission electron microscopy - XRD X-ray diffraction