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991.
The responsiveness of DCs and their precursors to transforming growth factor beta1 (TGF‐β1) affects the nature of differentiating DC subsets, which are essential for the severity of atopic dermatitis (AD). To evaluate TGF‐β signaling in monocytes and monocyte‐derived DCs of AD patients compared with that of controls, in vitro generated Langerhans cell (LC) like DCs, expression of TGF‐β receptors, phospho‐Smad2/3 and Smad7 were evaluated. Furthermore, TNF‐α expression and synergistic effects of TNF‐α upon TGF‐β signaling and DC generation were evaluated. We found LC‐like DC differentiation of monocytes from AD patients in response to TGF‐β1 was remarkably reduced and TGF‐β1 receptor expression was significantly lower compared with that of healthy controls. Attenuated TGF‐β1 responsiveness mirrored by lower phospho‐Smad2/3 expression after TGF‐β1 stimulation and higher expression of inhibitory Smad7 was observed in monocytes from AD patients. During DC generation, mRNA expression of Smad7 was relatively higher in LC‐like DCs of AD patients. Lower TNF‐α expression of monocytes from AD patients might further contribute to attenuated TGF‐β signaling in the disease since TNF‐α had synergistic effects on TGF‐β1 signaling and LC generation through mediating the degradation of Smad7. Our results demonstrate alleviated TGF‐β1 signaling together with the amount of soluble co‐factors might direct the nature of differentiating DCs.  相似文献   
992.
993.
Objective To compare the quality and quantity of total RNA from different source-original neurons applied in LMPC technique. Methods (1) Aglient 2100 bioanalyzer and RT-PCR were used to check the concentration and fragmentation of total RNA from unfixed, temporal fixed and fixed 12 h hypothalamus sections; (2) Different neurons of PVN and SON were collected by LMPC, CRH, TRH, AVP, OT mRNA level were measured by RT-PCR; (3) Labeled neurons by injecting CTB into stomach and non-labeled neurons in DMV collected by LMPC were checked for house keeping genes by RT-PCR. Results (1) Unfixed section had higher concentration and better quality of total RNA compared with fixed sections applied in LMPC; relative short amplicons such as GAPDH, NSE, MCH and MC4R were successfully obtained from fixed and unfixed and long amplicon of GR can only be obtained from unfixed material; (2) In magnocellular PVN and SON the expressions of AVP and OT were more special than those in the parvocellular PVN. Oppositely, the expressions of CRH, TRH in the parvocellular were more special than the other two; (3) The expressions of house keeping genes had no significant difference between labeled and non-labeled DMV neurons. Conclusion The quality and quantity of total RNA from unfixed brain tissues were better than fixed tissues applied in LMPC and the CTB tracer which may differentiate neurons had no significant effect on physiology of the neurons applied in LMPC. The results showed that the LMPC technique is suitable for the qualitative and quantitative study on individual neurons at mRNA level.  相似文献   
994.
995.
996.
The elucidation of the human genome has had a major impact on histamine receptor research. The identification of the human H4 receptor by several groups has been instrumental for a new appreciation of the role of histamine in the modulation of immune function. In this review, we summarize the historical developments and the molecular and biochemical pharmacology of the H4 receptor.  相似文献   
997.
998.
To translate science into clinical practice we must first assess the quality of care that is being delivered. The resulting information about qualitative and quantitative parameters can then be assessed. Ultimately insights can be obtained into improving the quality of care in diabetes mellitus. The Diabetes Quality Improvement Programme in USA has shown such an exercise is feasible. A similar exercise in India is necessary to improve the quality of diabetes care.  相似文献   
999.
1000.
Sterility of plastic tubing welds in components stored at room temperature   总被引:2,自引:0,他引:2  
BACKGROUND: The ability of a sterile connecting device to maintain sterility when being used to weld tubing of a blood component to be stored at room temperature, such as a platelet unit, has not been adequately documented, nor has it been determined when the tubing to be welded is filled with liquid. STUDY DESIGN AND METHODS: The sterility of sterile connecting device welds of polyvinylchloride tubing were challenged after intentional contamination of the exterior of the tubing with both gram-positive and gram-negative organisms (4 × 10(4) to 3 × 10(6) colony-forming units/mL). Welding (n = 244) was performed with the contaminated area either being wet or having been allowed to dry. At the time of the welding, the tubing segments were either empty or filled with liquid (either aliquots of white cell-reduced apheresis platelets or bacteriologic growth medium). After the welding, the liquid was passed across the weld and held in the attached transfer pack for 5 to 7 days at room temperature. RESULTS: Two welds were found to be incomplete and leaky, and both of the units involved had positive cultures. One transfer pack had inadvertently been contaminated at the time of its initial, postweld culture by a bacterium other than the one used in the experiment. Aside from these three nonevaluable units, all of the welds were sterile when cultured after the packs were held for 5 to 7 days. CONCLUSION: This study documents the ability of the sterile connecting device to maintain a closed system in the welding of blood component units to be maintained at room temperature. All welds should be closely inspected at the time of completion to detect leaks that may lead to contamination.  相似文献   
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