织构复合水凝胶体系的假说

生物软组织可视为具有多层次结构的织构复合水凝胶体系(TCHS)、以水凝胶复合元件(HCE)为基本的构件(CP),通过一定的组合、排列方式构筑一系列多层次结构的不同软组织。软组织中任何层次的结构单元既可视为织构复合水凝胶体系又可视为构件。任何层次的TCHS中,构件的结构及其组合排列方式决定着该层次单元的功能。以织构复合水凝胶体系的观点考察了真核细胞、角膜和骨骼肌的多层次结构。双层网络水凝胶、皮芯复合水凝胶纤维人工肌肉模型、时空匹配可降解细胞支架等研究成果初步地证明了提出织构复合水凝胶体系观点的合理性。     

The relationship between right duct lymph flow and extravascular lung water in dogs given alpha-naphthylthiourea.

The relationship between right duct lymph flow and extravascular lung water was studied in 3 normal dogs and 15 dogs with pulmonary edema induced by alpha-naphthylthiourea (ANTU). Right duct lymph was collected in a pouch created by ligating jugular, subclavian, and brachiocephalic veins. Extravascular lung water was measured in vivo by double indicator dilution and post-mortem by weighting lungs before and after drying. Cardiac output, pulmonary artery and pulmonary artery wedge pressures, and the concentration of protein and electrolytes in plasma and right duct lymph were determined. Eight lungs were examined by light and electron microscopy. There was a direct relationship between right duct lymph flow (RDLF in milliters per hour per gram dry lung) and extravascular lung water (Qwl in milliliters per gram dry lung) which was best described by the equation RDLF=0.75-0.26 Qwl+0.03 (Qwl).2 Dogs with severe ANTU-induced edema had extensive lung capillary endothelial destruction but only mild interstitial swelling and no visible damage to type I alveolar epithelial cells. Cardiac output, pulmonary artery and wedge pressures, and protein and electrolyte concentrations did not correlate with either extravascular water or right duct flow. Thus, in ANTU-induced pulmonary edema right duct lymph flow was directly related to extravascular lung water with the highest flows occurring with severe edema. The absence of a rapid increase in lymph flow with small increases in extravascular water may be due to early sequestration of fluid in the alveolar space. Hemodynamic changes did not account for changes in lung water or lymph flow. The pulmonary interstitial factors relating increased extravascular water to lymph drainage remain to be determined.     

Non‐invasive imaging of mid‐dermal elastolysis

Mid‐dermal elastolysis (MDE) is a rare disease that is characterized histopathologically by selective loss of elastic tissue in the mid dermis. We aimed to assess MDE using noninvasive skin imaging techniques in vivo. We examined both the lesional and adjacent healthy skin of a woman with the reticular variant of MDE, using confocal scanning laser microscopy, optical coherence tomography (OCT) and high‐frequency ultrasound (HFUS). The median diameter of blood vessels at the top of dermal papillae was significantly increased in erythematous lesional skin compared with healthy skin. The mid‐dermal signal intensity detected by OCT was higher in healthy skin than in lesional skin. With HFUS, mid‐dermal density values were significantly higher in healthy skin than in lesional skin. Our preliminary findings indicate that noninvasive skin imaging methods such as OCT and HFUS might be suitable techniques for the evaluation and monitoring of elastolytic skin disorders such as MDE.     

Evidence of circulation of an epidemic strain of <Emphasis Type="Italic">Francisella tularensis</Emphasis> in France by multispacer typing

Multispacer typing (MST) was used to type ten Francisella tularensis strains detected in French patients. Incorporating 79 Swedish F. tularensis strains, phylogenetic analysis demonstrated that although tularemia appears as a sporadic disease in France, it is caused by an epidemic cluster of strains.     

骨髓基质干细胞移植对正常和心肌梗死大鼠心电图及心功能的影响

目的:骨髓基质干细胞移植到心肌梗死的瘢痕心肌组织中可以改善心功能,但以心电图为观察指标的研究不多。实验观察骨髓基质干细胞移植对正常和心肌梗死大鼠心电图及心功能的影响。方法:实验于2004-01/2005-03在哈尔滨医科大学完成。①实验动物:选取4周龄雄性Wistar大鼠80只,随机数字表法分为梗死移植组、正常移植组、梗死非移植组、正常非移植组,20只/组。另选取7d龄Wistar雄鼠30只作为骨髓基质干细胞的来源。②实验方法:采用密度梯度离心法获取鼠骨髓基质干细胞,配成1×109L-1的细胞悬液,使用5-氮胞苷体外诱导培养3～4周,移植前24～48h行Brdu标记。取载有细胞的盖玻片,测定钙释放时将20mmol/L的caffeine快速加在细胞表面。梗死移植组、梗死非移植组大鼠建立心肌梗死模型。造模4周后,梗死移植组将0.25mL诱导的骨髓基质干细胞悬液注射至大鼠心肌梗死后的瘢痕组织,正常移植组同法将骨髓基质干细胞悬液注射至正常心肌组织,梗死非移植组、正常非移植组注射等量不含骨髓基质干细胞的培养液基质。③实验评估:观察骨髓基质干细胞的诱导分化情况及其植入后在瘢痕心肌组织中的生存状态。测定细胞内钙离子浓度。记录术前、冠脉结扎后即刻/细胞移植即刻、术后4周的心电图变化。检测术后4周的超声和血流动力学指标变化。结果:80只大鼠均进入结果分析。①骨髓基质干细胞的诱导分化及其植入后的生存状态:5-氮胞苷诱导3周后,骨髓基质干细胞表达肌钙蛋白Ⅰ和肌凝蛋白重链,细胞内有丰富的肌丝和Z线,细胞器较多。植入4周后在心肌瘢痕组织中分化为心肌细胞。②细胞内钙离子浓度:两组细胞在caffeine刺激下钙离子的释放均呈波峰状,但诱导组应用caffeine后钙离子浓度降低且低于基础状态,钙释放受到抑制,未诱导组不受影响。③心电图观察:与术前比较,梗死移植组QRS波变窄,R波降支出现正常顿挫波,未见显著心律失常。④超声检测及血流动力学分析:术后4周,与梗死非移植组比较,梗死移植组左室收缩末压、左室射血分数和压力变化速率最大值均显著升高(P<0.05或0.01)。结论:骨髓基质干细胞体外诱导后能分化为心肌样细胞,植入到瘢痕心肌组织中生存、增殖良好,可改善心电图及心肌弹性,从而改善心肌梗死大鼠的心功能。     

Percutaneous umbilical blood sampling and umbilical vein transfusions. Rapid serologic differentiation of fetal blood from maternal blood

Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases.