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A One–Step, Operator–Independent Method for Isolating Islets of Langerhans from the Porcine Pancreas
Christophe Arbet–Engels Sylviane Darquy Frédérique Capron Maria E. Pueyo Sophie Dimaria Vincent Poitout Gérard Reach 《Artificial organs》1994,18(8):570-575
Abstract: Large–scale isolation of islets of Langerhans is one of the major obstacles in islet transplantation. Until now, isolation methods relied on enzymatic digestion, the duration of which relies on a decision dictated by the operator's experience. This approach has always hindered development of an automated method. The aim of this study was to develop a one–step method based on complete digestion of the pancreas. The original aspect of the technique (derived from the Ricordi method) is use of the University of Wisconsin (UW) solution in the digestion medium and a continuous flow collagenase processing circuit with local cooling and rewarming to allow tissue digestion to proceed at 37°C while settling of the cell suspension takes place at 4°C. A stopcock system permits the alternate use of two settling chambers so that while one is in the circuit, the other can be removed for cen–trifugation, resuspension of the crude islet preparation in collagenase in free UW solution, and further purification in a density gradient system. Ten experiments were performed, and 545, 750 ± 48, 670 purified pig islets were obtained per totally digested pancreas. Histological studies showed cell integrity. Insulin secretion in response to double glucose stimulation under perfusion conditions demonstrated the functional viability of the isolated islets. In conclusion, this one–step method makes it possible to obtain a high number of viable islets of Langerhans in the absence of any decision by an operator, and it should therefore provide basis for an automated method. 相似文献
3.
Jochen Wolffgramm 《Psychopharmacology》1990,101(2):233-239
To study the effects of different kinds of social deprivation on voluntary ethanol (ETOH) intake male Wistar rats were housed by (a) individual caging, (b) contact caging (partial social deprivation), and (c) group caging (four individuals per cage). In the latter condition the individuals were separated once a week from each other for 24 h. The rats simultaneously received water 5%, 10% and 20% ETOH for a period of 14 weeks. Additional control animals received water. Isolated individuals drank significantly more alcohol than group-housed or contact-caged rats. After a few days they preferred the 20% solution. Circadian measures revealed a discontinuous intake of high doses (> 0.5 g/kg/h) during short time periods. Contact-caged rats consumed much less ETOH, but both the preference for 20% ETOH and the circadian course of intake were similar to those occurring after isolation. ETOH intake of group-housed individuals was low. These individuals preferred the 5% solution and continuously consumed small ETOH doses. During the period of short-term isolation they drank even more ETOH than long-term isolated individuals. In contrast to the latter, the enhancement of intake decreased after some weeks. It is suggested that the differences between the housing groups not only reflect different degrees of isolation stress, but may also be explained by a contribution of different reinforcing or aversive psychotropic effects of ETOH. Reduction of isolation stress is probably most important in the situation of short term separation, whereas dose-dependent reinforcement via social stimulation or sedation may affect the drug taking behavior under the other social conditions. 相似文献
4.
PreliminaryevaluationofpelvicvascularbedisolationchemotherapyinthetreatmentofadvancedcervicalcarcinomaJiangSenandPostgraduate... 相似文献
5.
Jan Piet Franke Jaap Wijsbeek Jan E. Greving Rokus A. de Zeeuw 《Archives of toxicology》1978,42(2):115-121
The potentials of XAD-columns for the isolation of quaternary ammonium compounds from aqueous media have been investigated. When adequate amounts of counter ions (perchlorate, chloride, phosphate, nitrate) were added to the aqueous sample, to the column pretreatment fluid and to the aqueous washing fluid, most quaternary compounds investigated were retained on the column and could be recovered by elution with methanol. This approach proved also suitable for urine. Quantitation of quaternaries isolated in this way from urine samples could be performed on silicagel thin layer plates through visualization with iodine, followed by densitometric evaluation. For decamethonium detection limits were 0.1 g/ml. Recoveries at the 1 g/ml level were between 80–90% with variation coefficients of less than 10%.Presented at the European Meeting of The International Association of Forensic Toxicologists, July 4–7, 1978, Utrecht, The Netherlands 相似文献
6.
目的:总结艾滋病病毒HIV感染罹患皮肤烧伤的治疗和预防措施。方法:对1997年1月-2001年10月收治的两例烧伤前伴有艾滋病病毒感染病人隔离治疗,同时上报主管部门。结果:两例患烧伤创面均治愈出院,未发生并发症。建议到国家指定医疗单位采取强制性隔离治疗。结论:加强对入院烧伤病人HIV检测,避免HIV感染扩散。 相似文献
7.
表皮干细胞的快速高效分离 总被引:2,自引:0,他引:2
目的 寻找一种快递高效分离组织工程化皮肤种子细胞-皮肤干细胞的方法.方法 取成人手术切除之包皮,利用Ⅰ型胶原酶结合胰蛋白酶消化法,快速分离表皮干细胞,并对其进行鉴定及相关的生物学特性的研究.结果 应用Ⅰ型胶原酶结合胰蛋白酶,可在3小时内快速分离到表皮干细胞及成纤维细胞,经流式细胞仪及细胞免疫荧光鉴定,表皮细胞群体中角蛋白19(K19)阳性表达的细胞即表皮干细胞约占18%,但是其体外短期扩增仍较困难.结论 利用胶原酶消化法可在短期内高效分离到用于构建组织工程化皮肤的种子细胞,这为快速构建组织工程化皮肤提供了可能. 相似文献
8.
目的 从空间设施布局优化的角度探讨疫情下的医院服务区分布与基于服务区设置集中隔离点的方法。 方法 基于Huff模型描绘了上海市三级医院的服务区空间分布;以最大化覆盖率为目标,采用位置分配模型预测医院选址的优化布局,设置潜在的候选位置。 结果 在上海市可收治病例的三级医院中,中心地区医院密度高;城乡医院服务区空间分布差异明显,郊区医院的服务区面积大;优化配置布局的结果显示,可在松江区中心新增1家医院,在浦东新区中间区域增加适量医院。 结论 结合医院服务区分布,隔离点可以设置于各街道中与所属医院相近的位置,明确出现病例时各个隔离点对应送往的医院。优化布局建议在松江区和浦东新区增加三级医院。 相似文献
9.
目的摸索完善A型精原干细胞分离、纯化的方法与技术。方法选用9d的SD大鼠,不连续Percoll梯度液分离纯化精原干细胞,应用选择性贴壁法进一步纯化精原干细胞;台盼蓝排斥实验确定精原干细胞的活力;HE染色法观察细胞形态;c-kit细胞免疫组化鉴定细胞类型并进行细胞纯度分析。结果台盼蓝实验显示细胞活力维持于88.73%±0.85%;c-kit细胞免疫组化结果显示分离得到细胞为精原干细胞;细胞纯度为90.48%±1.78%。结论应用梯度离心及选择性贴壁法获得了纯度较高的A型精原干细胞。 相似文献
10.
中国6个KM小鼠群体外形形态特征调查 总被引:2,自引:1,他引:2
对来自我国南方6个科研机构饲养的KM小鼠的外形进行了调查,测量了成年KM小鼠(每个机构20♂,20♀)的体全长、尾长和头体长3个主要外形指标。结果显示:各群体间在这3项指标上存在着不同程度的差异,表明中国KM小鼠的外形特征出现了一定程度的种群分化。 相似文献