链脲佐菌素诱导的糖尿病早期小鼠胸主动脉钾通道变化

目的:探讨链脲佐菌素诱导的糖尿病早期小鼠胸主动脉钾通道的变化。方法:实验采用离体血管的方法测定糖尿病鼠和正常鼠胸主动脉环对血管收缩剂:60mmol/LKCl和苯肾上腺素(PE)、内皮非依赖性舒张剂:硝普钠(SNP)以及电压依赖性钾通道(K_V通道),钙激活型钾通道(K_Ca通道),ATP敏感钾通道(K_ATP通道)阻断剂的反应。结果:糖尿病鼠胸主动脉环对60mmol/LKCl、PE和SNP的效应都显著大于对照组;K_Ca通道阻断剂四乙铵(TEA)显著降低糖尿病小鼠胸主动脉环在PE的激动下SNP的舒张效应,而且其-logIC₅₀的差值较对照组显著增大;K_V通道阻断剂4-氨基吡啶(4-AP)显著降低糖尿病和正常小鼠胸主动脉环对SNP的舒张效应,但是-logIC₅₀差值无显著差异;K_ATP通道阻断剂格列苯脲(Glibenclamide)显著降低糖尿病小鼠胸主动脉环对SNP的舒张效应,而对照组无显著阻断作用,-logIC₅₀的差值也无显著差异。结论:糖尿病早期小鼠胸主动脉平滑肌细胞K_Ca通道的开放或表达显著增强,也证实了K_ATP通道开放增强。     

Cortisol and testosterone concentrations in wheelchair athletes during submaximal wheelchair ergometry

It is yet unknown how upper body exercise combined with high ambient temperatures affects plasma testosterone and cortisol concentrations and furthermore, how these hormones respond to exercise in people suffering spinal cord injuries. The purpose of this study was to characterize plasma testosterone and cortisol responses to upper body exercise in wheelchair athletes (WA) compared to able-bodied individuals (AB) at two ambient temperatures. Four WA [mean age 36 (SEM 13) years, mean body mass 66.9 (SEM 11.8) kg, injury level T₇–T₁₁], matched with five AB [mean age 33.4 (SEM 8.9) years, mean body mass 72.5 (SEM 13.1) kg] exercised (cross-over design) for 20 min on a wheelchair ergometer (0.03 kg resistance · kg⁻¹ body mass) at 25 °C and 32 °C. Blood samples were obtained before (PRE), at min 10 (MID), and min 20 (END) of exercise. No differences were found between results obtained at 25 °C and 32 °C for any physiological variable studied and therefore these data were combined. Pre-exercise testosterone concentration was lower (P < 0.05) in WA [18.3 (SEM 0.9) nmol · l⁻¹] compared to AB [21.9 (SEM 3.6) nmol · l⁻¹], and increased PRE to END only in WA. Cortisol concentrations were similar between groups before and during exercise, despite higher rectal temperatures in WA compared to AB, at MID [37.21 (SEM  0.14) and 37.02 (SEM  0.08)°C, respectively] and END [37.36 (SEM 0.16) and 37.19 (SEM 0.10)°C, respectively]. Plasma norepinephrine responses were similar between groups. In conclusion, there were no differences in plasma cortisol concentrations, which may have been due to the low relative exercise intensities employed. The greater exercise response in WA for plasma testosterone should be confirmed on a larger population. It could have been the result of the lower plasma testosterone concentrations at rest in our group. Accepted: 4 September 2000     

Decellularized ureter for tissue-engineered small-caliber vascular graft

Previous attempts to create small-caliber vascular prostheses have been limited. The aim of this study was to generate tissue-engineered small-diameter vascular grafts using decellularized ureters (DUs). Canine ureters were decellularized using one of four different chemical agents [Triton-X 100 (Tx), deoxycholate (DCA), trypsin, or sodium dodecyl sulfate (SDS)] and the histology, residual DNA contents, and immunogenicity of the resulting DUs were compared. The mechanical properties of the DUs were evaluated in terms of water permeability, burst strength, tensile strength, and compliance. Cultured canine endothelial cells (ECs) and myofibroblasts were seeded onto DUs and evaluated histologically. Canine carotid arteries were replaced with the EC-seeded DUs (n = 4). As controls, nonseeded DUs (n = 5) and PTFE prostheses (n = 4) were also used to replace carotid arteries. The degree of decellularization and the maintenance of the matrix were best in the Tx-treated DUs. Tx-treated and DCA-treated DUs had lower remnant DNA contents and immunogenicity than the others. The burst strength of the DUs was more than 500 mmHg and the maximum tensile strength of the DUs was not different to that of native ureters. DU compliance was similar to that of native carotid artery. The cell seeding test resulted in monolayered ECs and multilayered alpha-smooth muscle actin-positive cells on the DUs. The animal implantation model showed that the EC-seeded DUs were patent for at least 6 months after the operation, whereas the nonseeded DUs and PTFE grafts become occluded within a week. These results suggest that tissue-engineered DUs may be a potential alternative conduit for bypass surgery.     

肩胛骨前后联合入路治疗陈旧性浮肩损伤（附6例报告）

目的：探讨肩胛骨前后联合入路治疗陈旧性浮肩损伤的临床疗效。方法：采用肩胛骨前后联合入路对6例陈旧性浮肩损伤进行手术治疗。结果：根据Herscovici功能评估标准，其中优1例，良2例，可3例，无血管神经副损伤。结论：采用肩胛骨前后联合入路处理陈旧性浮肩损伤，术野显露清楚，易于操作与复位固定，可以有效地避开血管神经，安全可靠。     

Isolation and characterization of human smooth muscle cells from umbilical cord vein and their reconstitution in a vascular co-culture model with underlying endothelial cells

Smooth muscle cells have been isolated from human umbilical cord veins, characterized and cultured for the development of an endothelialsmooth muscle cell co-culture system. After harvesting endothelial cells, the umbilical cords were trimmed of amnion, connective tissue and arteries, split into pieces, cut open longitudinally and placed with the luminal surface of the explant down onto a culture plate, without the use of proteolytic enzymes. Adherent primary cells were sequentially passaged and various cytological/biochemical characterizations were performed between passages 2 and 10. Cells stained positive for antibodies against smooth muscle actin, negative for antibodies against factor VIII and displayed typical hill and valley morphology when confluent. Cell proliferation was stimulated and supported in a concentration-dependent manner by both human serum and fetal bovine serum over the range 1%–20%. The use of human serum at concentrations >10% decreased the population doubling time during exponential growth by circa 50%. The cells were also characterized by high seeding efficiencies (>70%) and retained their diploid karyotype for up to 3 months in culture. Endothelial cells and smooth muscle cells prepared from umbilical veins were then seeded at varying densities onto either side of porous tissue culture inserts coated with fibronectin. Utilising the measurement of electrical resistance, the optimal seeding density of 5×10⁴ cells/cm² for each cell type gave maximal resistance across the cell bi-layer already after 24 hours, which remaining essentially unaltered for up to 4 days of culture and which was always substantially higher than the resistance of filters seeded only with endothelial cells on one side. This was not substantially affected either by increasing passage of the HUVSM cells cultured with a fixed passage of endothelial cells, or by varying the donor origin of the endothelial cells. In terms of functionality of the selective permeability of the model, the calcium ionophore ionomycin (25 M), added to the endothelial side of the bi-layer, caused a 30% reduction in the electrical resistance across the co-culture within 60 minutes, with control resistance being re-established within 1 hour of removal of the ionophore by washing. These results clearly indicate that smooth muscle cells and endothelial cells prepared from the same human blood vessel can be reconstituted into a functional vascular model suitable for the study of biochemical, physiological and toxicological phenomena in the human vascular wall.Abbreviations BCA bicinchoninic acid - BSA bovine serum albumin - DMEM DMEM medium supplemented with 4.5 g/l glucose, 100 IU/ml penicillin, 100 g/ml streptomycin and 1.25 g/ml fungizone - DMEM-1 DMEM supplemented with 20% FBS, 300 IU/ml penicillin, 300 g/ml streptomycin and 3.75 mg/ml fungizone - DMEM-2 DMEM supplemented with 20% FBS, 100 IU/ml of penicillin, 100 g/ml of streptomycin and 1.25 g/ml of fungizone - DMSO dimethyl sulfoxide - FBS fetal bovine serum - HPF human pulmonary fibroblasts - HS human serum - HUVE human umbilical vein endothelial - HUVSM human umbilical vein smooth muscle - M199 M199 medium supplemented with 20% HS, 100 IU/ml penicillin, 100 g/ml streptomycin, 1.25 g/ml fungizone and 2 mM L-glutamine - P passage number - PBS phosphate buffered saline - TCA trichloroacetic acid - vwF von Willebrand factor (factor VIII)     

具有三层管壁结构组织工程血管支架的生物力学性能

目的针对组织工程血管的体内培养技术路线，对所制备的具有三层管壁结构的组织工程血管支架的生物力学性能进行测试，并研究了壁厚对支架力学性能的影响，以保证后续的动物体内移植实验能顺利进行。方法采用涂敷，喷涂．滤沥的方法制备了具有三层管壁结构（多孔PLGA层．致密PU层．多孔PLGA层）的可降解组织工程血管支架，用自制的设备测试了其爆破强度和径向顺应性，并对血管支架进行了缝合强度的测试。结果所制备的厚度为0．295mm-0．432mm的三层结构血管支架的径向顺应性为3．80％／100mmHg-0．57％／100mmHg，爆破强度为160kPa～183kPa，缝合强度为0．63N／针～1．52N／针。结论支架的管壁厚度，尤其是中间层厚度，对支架的力学性能有重要影响。增大壁厚可导致径向顺应性急剧下降，爆破强度和缝合强度线性提高。在所制备的样品中，管壁厚度为0．295mm的支架其综合力学性能最优，可满足血管组织工程体内植入的力学性能要求。     

以骨间前血管为蒂前臂骨膜骨瓣的临床应用

应用骨间前血管为蒂.桡、尺骨骨膜骨瓣移位治疗上肢骨不连或骨缺损38例,均获得成功。该术式与以桡、尺动脉为蒂的桡、尺骨骨膜骨瓣移位相比较,有不损伤前臂主要血管干、移位范围大、适应症较广和操作简便易推广等特点.     

狗颌面高速投射伤区小血管病理改变

用光镜、电镜观察狗颌面高速投射伤区小血管的病理变化。实验发现:伤区小血管可见内皮细胞缺失、管壁断裂及细胞内的变性、坏死等病理变化,外径1.0～2,5mm的小血管损伤可远达距伤缘3.0cm处,该处血管7d后基本恢复。提示:临床运用血管化游离组织移植修复颌面部火器伤后的组织缺损时,其血管蒂应与距伤缘3.0cm以外的受区血管吻合,手术最好在伤后7d进行。     

A composite poly-hydroxybutyrate-glial growth factor conduit for long nerve gap repairs

There is considerable evidence that peripheral nerves have the potential to regenerate in an appropriate microenvironment. We have developed a novel artificial nerve guide composed of poly 3-hydroxybutyrate (PHB) filled with glial growth factor (GGF) suspended in alginate hydrogel. Gaps of 2-4 cm in rabbit common peroneal nerve were bridged using a PHB conduit containing either GGF in alginate hydrogel (GGF) or alginate alone (Alginate), or with an empty PHB conduit (Empty). Tissues were harvested 21, 42 and 63 days post-operatively. Schwann cell and axonal regeneration were assessed using quantitative immunohistochemistry. At 21 days, addition of GGF increased significantly the distance of axonal and Schwann cells regeneration in comparison with that observed in Alginate and Empty conduits for both gap lengths. The axons bridged the 2-cm GGF conduits gap by 63 days, with a comparable rate of regeneration seen in 4-cm conduits. Schwann cells and axonal regeneration quantity was similar for both gap lengths in each group. However, at all time points the quantity of axonal and Schwann cells regeneration in GGF grafts was significantly greater than in both Alginate and Empty conduits, the latter showing better regeneration than Alginate conduits. The results indicate an inhibitory effect of alginate on regeneration, which is partially reversed by the addition of GGF to the conduits. In conclusion, GGF stimulates a progressive and sustainable regeneration increase in long nerve gap conduits.     

百草枯中毒致肺损伤的CT表现

目的探讨百草枯中毒致肺损伤中的CT检查影像学特征和诊断价值。方法回顾性分析15例口服百草枯中毒致肺损伤病例的CT影像学资料。结果15例患者中毒早期（1～7d）主要CT表现包括支气管血管柬增粗伴支气管扩张显示轨道征（15／15）、磨玻璃密度影（14／15）、马赛克征（12／15）、树芽征（8／15）、肺实变（6／15）及胸膜下线（6／15）等；中毒中期（8～14d）主要表现支气管血管束增粗伴支气管扩张显示轨道征（11，11）、肺实变（7／11）及磨玻璃密度影（6／11）；中毒后期（〉14d）CT表现以肺实变（1／1）和纤维化（1／1）为主。结论百草枯中毒的肺部CT表现具有一定的特征性，其影像学变化对病情发展及指导临床治疗具有重要意义。