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BACKGROUND: We evaluated a clinical-grade protocol for the manufacture of mature DC from CD14 + precursors derived from normal donors and patients suffering from CML and stage IV malignant melanoma. We manufactured six products for CML patients and five for melanoma patients and administered them as vaccines in phase I clinical trials. METHODS: We isolated CD 14+ cells from apheresis products by immunomagnetic separation and incubated them in X-VIVO 15' medium supplemented with human AB serum, GM-CSF and IL-4 for 7 days, and with additional tumor necrosis factor (TNF)-a, IL-lIf, IL-6 and prostaglandin E2 for 3 days. Some cells were electroporated and transfected with mRNA isolated from melanoma tissue. DC were characterized by flow cytometry for the expression of CD83, CD86 andCD14. RESULTS: CD14+ cells constituted 14.4+/-6.2% (mean + SD) of nucleated cells in apheresis products and 98.3+/- 3.6% of isolated cells. Normal DC and CML DC were 77.4+/-7.3% CD83+ and 93.5+/- 7.0% CD86+.Corresponding values for electroporated DC from melanoma patients were 66.1 + 7.2% and 94.1 + 7.8%. The yield of CD83+ DC from isolated CD14+ cells was 18.1 + 7.2% for normal and CML patients and 9.8 + 3.7% for melanoma patients. DC viability was 92.7 + 5.8%; after cryopreservation and thawing it was 77+/-13.5%. DISCUSSION: Our method yielded viable and mature DC free of bacteria and mycoplasma. This robust and reproducible method provides cells of consistent phenotype and viability. Cryopreservation in single-dose aliquots allows multiple DC vaccine doses to be manufactured from a single apheresis product.  相似文献   
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The metabolism of the illegal growth promoter ethylestrenol (EES) was evaluated in bovine liver cells and subcellular fractions of bovine liver preparations. Incubations with bovine microsomal preparations revealed that EES is extensively biotransformed into norethandrolone (NE), another illegal growth promoter. Furthermore, incubations of monolayer cultures of hepatocytes with NE indicated that NE itself is rapidly reduced to 17α-ethyl-5β-estrane-3α,17β-diol (EED). In vivo tests confirmed that, after administration of either EES or NE, EED is excreted as a major metabolite. Therefore, it was concluded that, both in urine and faeces samples, EED can be used as a biological marker for the illegal use of EES and/or NE. Moreover, by monitoring EED in urine or faeces samples, the detection period after NE administration is significantly prolonged. These findings were further confirmed by three cases of norethandrolone abuse in a routine screening program for forbidden growth promoters.  相似文献   
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Background

The importance of effective clinical teaching for the quality of future patient care is globally understood. Due to recent changes in graduate medical education, new tools are needed to provide faculty with reliable and individualized feedback on their teaching qualities. This study validates two instruments underlying the System for Evaluation of Teaching Qualities (SETQ) aimed at measuring and improving the teaching qualities of obstetrics and gynecology faculty.

Methods and Findings

This cross-sectional multi-center questionnaire study was set in seven general teaching hospitals and two academic medical centers in the Netherlands. Seventy-seven residents and 114 faculty were invited to complete the SETQ instruments in the duration of one month from September 2008 to September 2009. To assess reliability and validity of the instruments, we used exploratory factor analysis, inter-item correlation, reliability coefficient alpha and inter-scale correlations. We also compared composite scales from factor analysis to global ratings. Finally, the number of residents'' evaluations needed per faculty for reliable assessments was calculated. A total of 613 evaluations were completed by 66 residents (85.7% response rate). 99 faculty (86.8% response rate) participated in self-evaluation. Factor analysis yielded five scales with high reliability (Cronbach''s alpha for residents'' and faculty): learning climate (0.86 and 0.75), professional attitude (0.89 and 0.81), communication of learning goals (0.89 and 0.82), evaluation of residents (0.87 and 0.79) and feedback (0.87 and 0.86). Item-total, inter-scale and scale-global rating correlation coefficients were significant (P<0.01). Four to six residents'' evaluations are needed per faculty (reliability coefficient 0.60–0.80).

Conclusions

Both SETQ instruments were found reliable and valid for evaluating teaching qualities of obstetrics and gynecology faculty. Future research should examine improvement of teaching qualities when using SETQ.  相似文献   
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The analysis of traumatic fractures can provide valuable information concerning the affects of sociopolitical factors upon the health of prehistoric populations. However, such information can only be acquired by implementing a quantitative demographic approach. The present research applies such a method to longbone fractures in two medieval Christian populations excavated from ancient Nubia. Long-bones of two hundred and eighteen individuals from an early (550 to 750 A.D.) Christian cemetery and 188 individuals from a late (750 to 1450 A.D.) Christian cemetery were examined for evidence of traumatic fracture. Analysis included a determination of fracture rates, age and sex related fracture patterns, and rate of fracture per years at risk. The results of this study indicate that the majority of fractures in both cemeteries were likely caused by accidental falls. Fractures resulting from direct (possibly interpersonal) violence were found in both samples, though at a higher frequency in the early Christian population (27% versus 16%). Middle-aged adults (particularly males) of the early cemetery exhibited a higher than expected risk to fractures indicating an activity related cause of injury. In contrast, the late Christian population showed a marked increase in fractures among both children and the elderly. This distribution may reflect changes in health and residential architecture which occurred during the late Christian period.  相似文献   
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Msx2-deficient mice exhibit progressive hair loss, starting at P14 and followed by successive cycles of wavelike regrowth and loss. During the hair cycle, Msx2 deficiency shortens anagen phase, but prolongs catagen and telogen. Msx2-deficient hair shafts are structurally abnormal. Molecular analyses suggest a Bmp4/Bmp2/Msx2/Foxn1 acidic hair keratin pathway is involved. These structurally abnormal hairs are easily dislodged in catagen implying a precocious exogen. Deficiency in Msx2 helps to reveal the distinctive skin domains on the same mouse. Each domain cycles asynchronously - although hairs within each skin domain cycle in synchronized waves. Thus, the combinatorial defects in hair cycling and differentiation, together with concealed skin domains, account for the cyclic alopecia phenotype.  相似文献   
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Paroxysmal Kinesigenic Dyskinesia with Infantile Convulsions (PKD/IC) is an episodic movement disorder with autosomal dominant inheritance and high penetrance, but the causative gene is unknown. We have now identified four truncating mutations involving the PRRT2 gene in the vast majority (24/25) of well characterized families with PKD/IC. PRRT2 truncating mutations were also detected in 28 of 78 additional families. The PRRT2 gene encodes a proline-rich transmembrane protein of unknown function that has been reported to interact with the t-SNARE, SNAP25. PRRT2 localizes to axons but not to dendritic processes in primary neuronal culture and mutants associated with PKD/IC lead to dramatically reduced PRRT2 protein levels leading ultimately to neuronal hyperexcitability that manifests in vivo as PKD/IC.  相似文献   
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