Use of an in vitro model of tissue-engineered human skin to study keratinocyte attachment and migration in the process of reepithelialization

To produce a stable epidermis, keratinocytes need to be firmly attached to the basement membrane. However, following wounding, keratinocytes are required to develop a migratory phenotype in order to reepithelialize the wound. To investigate some of the issues underlying reepithelialization, we have developed a three-dimensional in vitro model of tissue-engineered skin, comprising sterilized human dermis seeded with human keratinocytes and dermal fibroblasts. Using this model, we have shown that the inclusion of fibroblasts within the model increases the stability of keratinocyte attachment. We have also demonstrated that keratinocyte migration occurs most effectively in the absence of a basement membrane and following the inclusion of fibroblasts in the model. In addition, subjecting the keratinocyte layer to mechanical trauma induces a migratory phenotype. We conclude that this three-dimensional in vitro wound model can be used to increase our understanding of the factors that enhance keratinocyte migration and hence wound healing in vivo.     

Intrapulmonary metastasis developing eighteen years after complete resection of thymoma

We present a case of intrapulmonary metastasis developing 18 years after complete resection of thymoma. An 8 mm nodule in the lower lobe of the left lung was noted on chest X-ray in a 76-year-old woman who had undergone complete resection of Masaoka’s stage II thymoma 18 years earlier. Since the nodule grew to 17 mm during a 2-year follow-up, wedge resection was performed. The lesion was histologically diagnosed as an intrapulmonary metastasis from thymoma. Extremely late recurrence after complete resection of thymoma is discussed.     

采用泌尿道前列腺切除器经肛门内镜切除直肠肿瘤：131例患者应用的经验

目的：直肠腺瘤和其他疑似为良性的病变应用经肛门内镜切除术并未普及。该项研究旨在评估经肛门内镜切除术的效能和安全性。方法：回顾性研究分析在1993-2004年之间3所斯德哥尔摩医院中经肛门内镜切除术的患，内容包括患自身及病变特性、并发症、随访时间和复发率。结果：180例中共131例行经肛门内镜切除术。160例经组织学诊断为腺瘤，12例为癌瘤，其余8例分别为增生、纤维化或正常黏膜。直肠腺瘤患中，77例仅行单次经肛门内镜切除术，16例因巨大腺瘤而多次行该手术，27例因复发而需另行经肛门内镜切除术或其他手术。中位复发时间为7个月，但未出现直肠癌。16例手术患出现并发症。2例患必须行Hartman手术，1例因肠穿孔，另1例因出血。手术期间无死亡。未复发的中位随访期为32个月（极差0—67）。[编按]     

Academic Degrees and Clinical Practice Characteristics: The University of Washington Physician Assistant Program: 1969-2000

CONTEXT: The physician assistant profession has been moving toward requiring master's degrees for new practitioners, but some argue this could change the face of the discipline. PURPOSE: To see if there is an association between physician assistants' academic degrees and practice in primary care, in rural areas, and with the medically underserved. METHODS: Surveys were sent to 880 graduates of the first 32 University of Washington physician assistant classes through 2000. Respondents noted their academic degree at program entry and the highest degree attained at any time up to the time of survey. Relationships between practice characteristics and academic degree levels were tested by unadjusted odds ratios and logistic regression after controlling for year of graduation and sex. RESULTS: Of the 478 respondents, 54% worked in primary care, about 30% practiced in nonmetropolitan communities, and 42% reported providing care for the medically underserved. Respondents with no degree (33% of total at entry, 24% at survey) were significantly more likely than degree holders to work in primary care and nonmetropolitan areas. Respondents with no degree at program entry were significantly more likely, and those with no degree at the time of the survey were marginally more likely, to self-report work with the medically underserved. CONCLUSION: Respondents with no academic degree are significantly more likely to demonstrate a commitment to primary, rural, and underserved health care. These findings may inform the national debate about the impact of required advanced degrees on the practice patterns of nonphysician providers.     

平价医院北京开局

去年12月21日，市场暌违已久的政府办平价医院——北京上地医院终于正式开诊。