Preparation and characterization of macroporous chitosan-gelatin/beta-tricalcium phosphate composite scaffolds for bone tissue engineering

A biodegradable composite scaffold was developed using beta-tricalcium phosphate (beta-TCP) with chitosan (CS) and gelatin (Gel) in the form of a hybrid polymer network (HPN) via co-crosslinking with glutaraldehyde. Various types of scaffolds were prepared by freezing and lyophilizing. These scaffolds were characterized by Fourier transform infrared, X-ray diffractometer, and scanning electron microscopy. The macroporous composite scaffolds exhibited different pore structures. Compressive properties were improved, especially compressive modulus from 3.9-10.9 MPa. Biocompatibility was evaluated subcutaneously on rabbits. A mild inflammatory response was observed over 12 weeks. The results suggest that the scaffolds can be utilized in nonloading bone regeneration.     

Development of loop-mediated isothermal amplification (LAMP) assay for rapid diagnosis of ovine theileriosis in China

Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid detection method in which the target deoxyribonucleic acid (DNA) can be efficiently amplified with high specificity and sensitivity under isothermal conditions using a set of either four or six specific primers. In this study, we have identified a conserved sequence for Theileria luwenshuni (UTRlu8) and for T. uilenbergi (UTRu6) suitable for designing a set of six primers for the simultaneous detection by LAMP of these pathogens causing theileriosis in sheep and goats in China. LAMP was performed at 63°C, and the amplified DNA was detectable within 15 min. The specificity of the reaction was confirmed through EcoRI restriction enzyme digestion analysis and sequencing. The assay was proven sensitive since specific amplification was obtained from 0.1 pg DNA of T. luwenshuni or T. uilenbergi. The LAMP assay was evaluated by testing 86 field samples in comparison to the reverse line blot method, showing a sensitivity and specificity of 66.0% and 97.4%, respectively. These results indicate that the LAMP assay is rapid and simple to run, cost effective, sensitive, and specific and has potential usefulness for application in diagnostics of and epidemiological studies on T. luwenshuni and T. uilenbergi infection of small ruminants.     

大学生自我和谐与心理健康水平关系研究

目的探讨大学生自我和谐与心理健康之间的关系。方法采用自我和谐量表（SCCS）和症状自评量表（SCL-90）测试了275名大学生。结果大学生总体自我和谐及“自我与经验的不和谐”、“自我的刻板性”因子均与心理健康状况呈显著的正相关,而且不同自我和谐水平的大学生在SCL-90上的得分有显著差异。回归分析结果进一步显示,“自我与经验的不和谐”、“自我的刻板性”对大学生心理健康影响最大,而贫困大学生受影响的程度大于普通大学生。结论引导大学生正确评价自己是促进大学生心理健康的有效途径,对于贫困大学生需加强有针对性的心理健康教育。     

In vitro activity of tigecycline against clinical isolates of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae, Serratia marcescens and Enterobacter cloacae

BACKGROUND AND PURPOSE: Strains of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae have spread widely in Taiwan hospitals. In this study, we evaluated the in vitro antimicrobial activity of tigecycline against ESBL-producing Enterobacteriaceae, including Klebsiella pneumoniae, Serratia marcescens and Enterobacter cloacae. METHODS: 104 confirmed ESBL-producing bacteria were isolated from 4 hospitals in mid- and southern Taiwan between 2000 and 2006. The in vitro activity of tigecycline against these ESBL producers was tested by use of Etest strips. RESULTS: The minimal tigecycline concentration at which 50% of isolates were inhibited and minimal concentration at which 90% of isolates were inhibited for ESBL-producing isolates ranged from 0.38 to 0.75 mug/mL and 0.5 to 1.5 mug/mL, respectively. CONCLUSIONS: Tigecycline, a new semisynthetic glycylcycline, may be considered an alternative drug of choice for patients infected with ESBL-producing bacteria.     

人鼻腔嗅粘膜嗅鞘细胞的原代培养和免疫组化观察

目的 建立人鼻腔嗅粘膜嗅鞘细胞（OECS）的体外培养方法。方法 利用鼻窦镜选取上鼻甲嗅区粘膜，原代培养嗅鞘细胞，进行形态学观察。结果 成功培养出人鼻腔嗅粘膜OECs，为扁平的双极、多极形态，对P75、GFAP呈阳性反应，纯度在50％左右。结论 人鼻腔嗅粘膜培养OECs的方法实用可行，但须在取材部位和纯化方面进一步探讨。     

Le FortⅠ截骨入路至斜坡的应用解剖

目的　为LeFortⅠ截骨入路切除斜坡区病变的临床应用提供解剖学基础。方法　随机选取经福尔马林保存的成人尸头 1 5具 ,用显微解剖技术对LeFortⅠ截骨入路从显露范围、安全程度、美容效果三方面进行评价。结果　斜坡区与脑桥、延髓腹侧及第Ⅴ～Ⅻ对脑神经关系密切 ,两侧毗邻破裂孔、颈内动脉、内耳门及颈静脉孔。颈内动脉管外口、破裂孔、颈静脉孔距中线最小间距分别为 2 2 9、8 4和 1 9 5mm。LeFortⅠ截骨入路与前方、侧方入路相比 ,具有手术野开阔、手术操作安全性高、对斜坡区显露良好 ,面部无瘢痕的优点。结论　了解斜破区各结构的形态及相互间的毗邻关系 ,可提高该区相关手术时的安全度和成功率 ,LeFortⅠ截骨入路可作为斜坡及其周围区域病变手术的一种良好选择 ,值得推广。     

软骨细胞上清液诱导滑膜间充质干细胞微团培养成软骨

背景：滑膜间充质干细胞在体外具有多向分化的能力,有望成为软骨组织工程中治疗软骨缺损的种子细胞,在其向软骨细胞分化过程中,合适的生长因子起了重要作用。 目的：利用富含生长因子的软骨细胞上清液诱导滑膜间充质干细胞向软骨细胞分化,并对其鉴定。 方法：采用消化法分别获得SD大鼠滑膜间充质干细胞、软骨细胞。收集软骨细胞上清液离心、过滤冻存备用。培养滑膜间充质干细胞至第3代后离心成微团,并用软骨细胞上清液进行成软骨诱导分化,通过形态学观察、免疫组织化学法、RT-PCR检测进行鉴定。 结果与结论：滑膜间充质干细胞使用软骨细胞上清液成软骨诱导21 d后,微团可见似软骨样组织。免疫组化法进行Ⅱ型胶原鉴定,基质能被Ⅱ型胶原染色,细胞染色呈现棕黄色。RT-PCR结果显示诱导后的微团表达软骨特异性基因Ⅱ型胶原和蛋白聚糖。证实软骨细胞分泌的可溶性因子可以诱导大鼠滑膜间充质干细胞向软骨方向分化。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

封闭负压引流干预慢性创面神经生长因子和微血管的变化

背景：随着老龄化程度的增加,慢性创面呈上升趋势,在治愈慢性创面方法匮乏的情况下,封闭负压引流技术开始应用于临床。　目的：观察封闭负压引流技术对人慢性创面组织中神经生长因子表达及微血管数量的影响,探索促进慢性创面愈合的机制。方法：以10例慢性创面患者为观察对象,其中胸部软组织缺损、骨髓炎伴骨外露和截肢后残端大面积皮肤缺损各1例、皮肤撕脱伤后创面感染2例、胫骨骨髓炎2例、术后伤口感染3例。分别于封闭负压引流技术吸引前、吸引7 d和14 d切取创周皮肤和创面内肉芽组织,采用免疫组织化学技术检测神经生长因子表达和微血管数量变化,并观察伤口愈合情况。结果与结论：封闭负压引流技术治疗7 d和14 d后成纤维细胞及血管内皮细胞中的神经生长因子表达明显高于治疗前(P < 0.001)。封闭负压引流治疗使微血管数量显著增加(P < 0.05-0.01)。封闭负压引流治疗前创基内肉芽组织量少且较晦暗,存在坏死组织和较多脓性分泌物,伤口周围组织肿胀明显。经封闭负压引流治疗后,伤口内坏死组织和脓性分泌物逐渐减少,肉芽组织呈细颗粒状,鲜红色,触之易出血,伤口周围水肿消退。提示封闭负压引流技术可以提高慢性创面创周组织中神经生长因子表达和微血管数量,促进创面愈合。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

体外大鼠肝卵圆细胞的长期培养方法

背景：肝卵圆细胞是目前公认的成体肝干/祖细胞,但其体外长期培养时会不可避免地丢失干细胞的活性。目的：探索大鼠肝卵圆细胞体外长期培养的方法。方法：构建2-乙酰胺基芴/部分肝切除肝再生大鼠模型,通过酶消化和Percoll梯度离心分离纯化大鼠异质卵圆细胞并进行免疫染色鉴定,用含表皮生长因子、白血病抑制因子的培养基体外长期培养,后撤去表皮生长因子、白血病抑制因子,通过形态学的观察和分子标志物的检测判断其能否保持干/祖细胞活性。结果与结论：采用含表皮生长因子、白血病抑制因子的培养基体外培养卵圆细胞4个月后,大鼠异质卵圆细胞仍能表达肝细胞标志物ALB、胆管上皮细胞标志物CK-19,经不含表皮生长因子、白血病抑制因子的培养液继续培养后,卵圆细胞胎肝标志AFP表达量迅速下降。该研究结果表明大鼠肝卵圆细胞在表皮生长因子、白血病抑制因子等培养条件下可长期增殖并保持干细胞活性。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：