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51.
Oxygen plays an important role in the cultivation of primary cellsex vivo. In this study, we used hermetically sealed tissue culture well inserts equipped with oxygen electrodes to measure the oxygen utilization of cultured human bone marrow mononuclear cells (BM MNCs). The oxygen uptake rate (OUR) of BM MNCs was determined during a 14-day culture in which both adherent and nonadherent cells were present. Early in the culture, the cells exhibited very low OURs. The specific OURs (uptake rate per cell) were at approximately 0.005 μmol/106 cells/hr shortly after the initiation of culture. The OUR then increased as the cultures developed. After about 8 to 10 days of cultivation the specific OURs had increased to 0.038±0.006 and 0.025±0.005 μmol/106 cells/hr for adherent and nonadherent cells, respectively, after which no further increase was observed. Based on these oxygen uptake rate data, a mathematical model of oxygen diffusion was formulated and use to investigate issues associated with hematopoietic bioreactor design, including initial cell density, medium depth, reactor configuration, and oxygen partial pressure.In situ OUR measurements confirmed predicted oxygen limitations based on the mathematical model and the experimentally determined OURs. High-density hematopoietic cultures present design challenges in terms of sufficient and uniform delivery of oxygen to an active hematopoietic culture. These challenges can be met by using parallelplate bioreactors with thin liquid layers.  相似文献   
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The role of mPer1 in morphine dependence in mice   总被引:6,自引:0,他引:6  
Liu Y  Wang Y  Wan C  Zhou W  Peng T  Liu Y  Wang Z  Li G  Cornelisson G  Halberg F 《Neuroscience》2005,130(2):383-388
Investigations using Drosophila melanogaster have shown that the circadian clock gene period can influence behavioral responses to cocaine, and the mouse homologues, mPer1 and mPer2, modulate cocaine sensitization and reward. In the present study, we applied DNAzyme targeting mPer1 to interfere the expression of mPer1 in CNS in mice and studied the role of mPer1 on morphine dependence. We found that the DNAzyme could attenuate the expression of mPer1 in CNS in mice. Mice treated with DNAzyme and morphine synchronously did not show preference to the morphine-trained side, whereas the control group did. In contrast, mice treated with DNAzyme after morphine showed preference to the morphine-trained side as well as the control group did. These results indicate that drug dependence seems to be influenced at least partially by mPer1, but mPer1 cannot affect morphine dependence that has been formed.  相似文献   
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彭鲁英  王云 《解剖学杂志》1990,13(3):230-233
本文研究丁敌枯双对BALB/C雄性小鼠生殖细胞分裂比率及精原细胞染色体畸变的影响。将实验小鼠随机分为三组,即实验组(敌枯双组),阳性对照组(环磷酰胺组)和阴性对照组(双蒸水组)。结果发现:敌枯双能明显诱发精原细胞多倍体率和裂隙率增加,抑制终变期/中期Ⅰ和中期Ⅱ细胞的减数分裂比率,促进精原细胞有丝分裂比率。实验结果还提示:在遗传毒理检测中亚急性实验是必要的,并对实验结果进行了初步讨论。  相似文献   
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The present study was undertaken to evaluate the systemic absorption and cervical tissue uptake of all-transretinoic acid (TRA), delivered via a collagen spongecervical cap delivery device in patients with intraepithelial cervical dysplasia. Ten patients with histologically proven mild or moderate cervical dysplasia were included in this pharmacologic study. The two TRA concentrations (0.05% and 0.372%) selected for study represent the starting and maximally tolerated doses used in phase I clinical trial. All-trans-retinoic-11-3H acid (3H-TRA, 500 Ci) was used to facilitate cervical tissue uptake studies. Cervical biopsies and post-treatment blood samples were obtained from each patient after TRA exposure. The uptake of TRA into cervical tissues four hours after drug administration was significantly increased at the maximally tolerated TRA dose. There was a rapid decrease in cervical tissue concentration of TRA at the 0.372% dose between 4 and 24 h after drug exposure, suggesting a relatively short elimination half-life of TRA in cervical tissues. HPLC analysis of post-treatment blood samples indicate that there was no systemic absorption of TRA after local cervical administration.  相似文献   
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目的 探讨醒脑静对急性重症一氧化碳 (CO)中毒的催醒作用。方法 在急性重症CO中毒常规综合抢救中加入醒脑静并与常规方法进行对比研究。结果 醒脑静治疗组较常规治疗组清醒时间明显缩短 (P <0 .0 1)。结论 醒脑静可作为急性重症CO中毒病人综合抢救中常规用药。  相似文献   
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Lei  Cao  Chuzhong  Li  Chunhui  Liu  Peng  Zhao  Jiwei  Bai  Xinsheng  Wang  Yazhuo  Zhang  Songbai  Gui 《Neurosurgical review》2021,44(3):1737-1746
Neurosurgical Review - Since there are many approaches for successful craniopharyngioma resection, how to choose a suitable approach remains problematic. The aim of this study was to summarize...  相似文献   
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ObjectivesTo investigate the effect and mechanism of macrophage activation and graft damage caused by nucleoside triphosphate diphosphohydrolase 1 (NTPDase1) in acute antibody-mediated rejection (AMR).MethodsAcute AMR was induced in different skin-grafted nude mouse models with wild-type NTPDase1 expression, transgene-enhanced NTPDase1 expression, or NTPDase1 gene knockout. Several methods (eg, real-time fluorescence quantitative polymerase chain reaction, high-performance liquid chromatography [HPLC], immunofluorescence, flow cytometry, and luciferin/luciferase assays) were used to study (at the histologic and molecular levels) the extracellular adenosine diphosphate (ADP) concentration, macrophage proliferation, major histocompatibility complex (MHC) class II antigen expression on the surface of macrophages, B-cell activating factor (BAFF) expression in the peripheral blood serum, and the total number of SmIg-positive B cells during acute AMR. The relative activity of NTPDase1 in B cells and epithelial cells, pathologic changes, and the incidence of positive C4d deposition around the capillaries of skin grafts on the different nude mice were studied.ResultsMacrophages proliferated significantly when acute AMR occurred. The higher the NTPDase1 expression level, the lower the extracellular ADP concentration, the expression of MHC class II antigens on the surface of macrophages, the expression of BAFF in the peripheral blood serum, and the total number of SmIg-positive B cells, indicating negative correlations. The relative activity of NTPDase1 in B cells and epithelial cells of the skin graft was different among the different mice. The higher the NTPDase1 expression level, the lower the degree of pathologic damage to the skin graft.ConclusionsImbalance in extracellular ADP degradation by NTPDase1 may promote macrophage activation, and activated macrophages may be an important cause of graft damage.  相似文献   
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