超声手术刀组织切割的实验研究

用国产超声手术刀，在大白兔活体上进行切割实验．并与普通手术刀和高频电刀进行了比较．结果显示超声手术刀的组织切割速度和切缘整齐情况不及普通手术刀，但有一定的止血功能，组织损伤不如高额电刀大，也不引起肌肉收缩，无组织烧焦气味；术后切缘愈合良好．认为超声手术刀更适合于肝、脾等实质性组织的切割．如在操作柄、刀具、仪器性能等方面能进一步改进，应用效果会更好。     

Immunohistochemical study on tissue transglutaminase and copper-zinc superoxide dismutase in human myocardium: Its relevance to apoptosis detected by the nick end labelling method

The influence of free radicals on apoptosis was studied in the human heart; 45 autopsy cases were examined by the nick end labelling method (NELM) that detects DNA fragmentation. Immunostaining for copper-zinc superoxide dismutase (CuZn-SOD) and tissue transglutaminase (tTG) induced frequently during apoptosis were also studied. Positive immunoreaction for tTG was detected in mucinous degeneration of myocardial cells; these same cells were also positive for CuZn-SOD but negative for NELM. Myocardial cells showing basophilic alterations after haematoxylin and eosin staining were also positive for CuZn-SOD but negative for the other markers examined. Positive nuclear reaction by NELM was only observed in myocardial cells showing contraction band necrosis or irregularly shaped nuclei surrounding recent or long-standing infarcted foci. In these the other two markers were negative. Since mucinous degeneration lacks the distinguishing morphological features of apoptosis, immunoreactive tTG in this lesion may not imply that the cells are undergoing apoptosis. tTG can be induced in non-apoptotic conditions and may not be involved in apoptosis induced by infarction. Histological disassociation between CuZn-SOD expression and apoptosis suggests the possibility of a cytoprotective role played by endogenous CuZn-SOD against free radical generation in the human heart.     

前臂后皮神经营养血管远端蒂筋膜皮瓣修复手部软组织缺损

目的：探讨前臂后皮神经营养血管远端蒂筋膜皮瓣修复手部软组织缺损的临床效果。方法：对18例手部创伤性软组织缺损创面采用带前臂后皮神经营养血管远端蒂筋膜皮瓣进行修复,其中机器绞伤11例,压砸伤5例,电锯伤2例,皮瓣面积最大为12cm×8cm,最小7cm×5cm。结果：17例皮瓣完全成活;1例皮瓣边缘部分坏死,经清创换药痊愈。术后随访6～12个月,皮瓣质地良好,外观满意。结论：前臂后皮神经营养血管远端蒂筋膜皮瓣切取简便、成功率高,是修复手部软组织缺损的理想供区。     

Preparation of a pure autologous biodegradable fibrin matrix for tissue engineering

Parallel to the growing role of tissue engineering, the need for cell embedding materials, which allow cells to stabilise in a three-dimensional distribution, has increased. Although several substances have been tested, fibrin is thus far the only one that permits the clinical application of cultured tissue. To date, can cause severe immunological side effects. The objective of this study was to explore the practicability of obtaining autologous thrombin from a single patient in an adequate concentration and amount. Fibrinogen was cryoprecipitated from 200 ml of freshly-frozen plasma. Thrombin was isolated from the supernatant through ionexchange chromatography. The thrombin was first bound to Sephadex A-50 and then eluated using 2ml of a salt buffer (2.0M NaCl in 0.015M trisodiumcitrate, pH 7.0). The activity of the thrombin (51 NIH ml⁻¹ to 414 NIH ml⁻¹) reached levels comparable to those in commercially available fibrin glues (4–500 NIH ml⁻¹). The study has shown that it is possible to obtain a sufficient amount of autologous thrombin from a single donor to create a fibrin matrix of high efficiency without the risk of immunological and infectious side effects.     

Mechanical and Cellular Changes During Compaction of a Collagen-Sponge-Based Corneal Stromal Equivalent

The need for corneas suitable for transplantation, combined with the decreasing supply, has fueled interest in the development of a corneal replacement. In this study, a collagen-sponge-based stromal equivalent, consisting of human corneal fibroblasts cultured on a type I collagen sponge, was maintained in culture for up to 21 days and characterized with respect to mechanical properties and cellular behavior. The Young's modulus of the stromal equivalent varied from 95 to 370 Pa, and its permeability varied from 5.3 x 10(-8) - 4.2 x 10(-7) m4 N(-1) s(-1). The greatest changes occurred during the first few days in culture, but the mechanical properties continued to change during the entire 21 days. Cell traction stress, determined from sponge compaction and DNA count, decreased during the compaction process with the maximum traction value the initial value of 6.6 +/- 2.9 x 10(-3) Pacm3 cell(-1). Microarray data showed that the expression level of fibronectin, decorin sulfate, collagenase, and gelatinase A was upregulated at day 14 in the sponge. This suggested that the repair fibroblast phenotype was being expressed by the fibroblasts. Additional analysis suggested that a subpopulation of cells expressed the myofibroblast phenotype.     

Evaluation of antidecubitus mattresses

Pressure sores are a current problem in hospitals and care of the elderly, leading to protracted hospital stays and a high care burden. The trauma for the patients is severe, and the cost of pressure sore prevention and treatment, is considerable. Antidecubitus mattresses are used for prevention and in treatment, but they also contribute to the cost of treating pressure sores. The problem highlighted in the review is that the mattresses' effectiveness in preventing and treating pressure sores has not been sufficiently evaluated. When antidecubitus mattresses are evaluated, it is often only with regard to aspects of the interface pressure and the mattresses' ability to redistribute the pressure. The review points out the important observation that, to be able to evaluate the efficacy of the antidecubitus mattress, the mattress's effect on tissue viability needs to be studied. The parameters that ought to be considered when evaluating a support surface are: interface pressure, pressure and blood flow distribution, temperature and humidity in the skin-support surface interface. The authors propose that the effect on tissue viability of external loading can be assessed by simultaneous measurement of the interface pressure and tissue perfusion.     

肺癌组织培养液和病人血清对自身T细胞集落形成能力的影响

本文观察了10例肺癌病人围术期的肺癌组织、正常肺组织培养液和血清对自身外周血T细胞集落形成能力的影响,并以14例正常人的血清作为对照。结果显示:肺癌人病在去肿瘤负荷前T细胞集落产率为160.73±124.02/10~5,故低于正常人的397.81±133.89/10~5(P<0.001),也低于去肿瘤负荷后的(P<0.001)306.53±79.86/10~5(P<0.001)。术前病人的血清对T细胞集落的抑制率为46.97±21.42%,术后则下降至27.63±23.25%(P<0.01)。加进肺癌组织培养液时,病人的T细胞集落产率为224.83±104.05/10~5,正常肺组织培养液则为323.12±125.27/10~5(P<0.001),肺癌组织培养液和病人血清两者对T细胞集落产率的抑制性呈正相关关系(r=0.817,P<0.005)。本研究结果认为,肺癌组织能产生细胞免疫抑制物质进入血循环,导致病人T细胞集落形成能力明显下降。手术根治性切除肺癌组织,能有效地解除T细胞集落形成能力受抑制的情况。     

纳米材料在组织工程体外细胞培养中的应用进展

组织工程包括细胞和生物支架两部分.其中细胞的活性在很大程度上取决于支架材料的优劣.良好的生物支架应该能尽可能地模拟细胞在体内的内环境,从而提供细胞生长所需的微环境.纳米材料由于很好地模拟了细胞在体内的拓扑结构,从而在组织工程领域得到了越来越广泛的应用.综述了纳米材料在各种细胞体外培养中的作用,初步探讨了纳米材料对细胞促进作用的机制,并对纳米材料在肝脏组织工程中的应用进行了展望.     

Expansion of human nasal chondrocytes on macroporous microcarriers enhances redifferentiation

Articular cartilage has a limited capacity for self-repair. To overcome this problem, it is expected that functional cartilage replacements can be created from expanded chondrocytes seeded in biodegradable scaffolds. Expansion of chondrocytes in two-dimensional culture systems often results in dedifferentiation. This investigation focuses on the post-expansion phenotype of human nasal chondrocytes expanded on macroporous gelatin CultiSpher G microcarriers. Redifferentiation was evaluated in vitro via pellet cultures in three different culture media. Furthermore, the chondrogenic potential of expanded cells seeded in polyethylene glycol terephthalate/ polybuthylene terephthalate (PEGT/PBT) scaffolds, cultured for 14 days in vitro, and subsequently implanted subcutaneously in nude mice, was assessed.

Chondrocytes remained viable during microcarrier culture and yielded doubling times (1.07±0.14 days) comparable to T-flask expansion (1.20±0.36 days). Safranin-O staining from pellet culture in different media demonstrated that production of GAG per cell was enhanced by microcarrier expansion. Chondrocyte–polymer constructs with cells expanded on microcarriers contained significantly more proteoglycans after subcutaneous implantation (288.5±29.2 μg) than those with T-flask-expanded cells (164.0±28.7 μg). Total collagen content was similar between the two groups.

This study suggests that macroporous gelatin microcarriers are effective matrices for nasal chondrocyte expansion, while maintaining the ability of chondrocyte differentiation. Although the exact mechanism by which chondrocyte redifferentiation is induced through microcarrier expansion has not yet been elucidated, this technique shows promise for cartilage tissue engineering approaches.