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31.
Background:  Chronic alcohol consumption reduces the percentage and number of peripheral natural killer (NK) cells in mice and in humans. The underlying mechanism for these changes is only partly known. We recently found that chronic alcohol consumption inhibits NK cell release from the bone marrow (BM) and that this is associated with a decrease in splenic NK cells. The number of peripheral NK cells is tightly controlled by homeostatic proliferation. It is not known whether this mechanism is initiated in response to the reduction in splenic NK cells, or if so, why the steady state levels of NK cells are not restored.
Methods:  To examine this mechanism, female C57BL/6 mice were given 20% w/v alcohol in the drinking water for 3 months. NK cell proliferation and apoptosis were determined before and after treatment with IL-15 alone or combined with its alpha receptor.
Results:  Chronic alcohol consumption invoked homeostatic proliferation of splenic NK cells in an attempt to return NK cells to normal levels; however, this did not happen due to enhanced apoptosis of NK cells relative to proliferation. Chronic alcohol consumption decreased IL-15 producing cells in the spleen but not in the BM. The numbers of NK cells in the alcohol-consuming mice returned to normal levels in the spleen and were higher than normal in the BM after 2 daily injections of IL-15; however, the enhanced rate of apoptosis due to alcohol consumption was not decreased in the spleen or BM. Combined IL-15 and IL-15Rα treatment decreased apoptosis of NK cells from alcohol-consuming mice to levels similar to untreated water-drinking mice and greatly increased the percentage and number of NK cells in both the spleen and BM.
Conclusion:  Chronic alcohol consumption causes a self-unrecoverable loss of NK cells in the spleen by compromising NK cell release from the BM and enhancing splenic NK cell apoptosis that can be reversed with IL-15/IL-15Rα treatment.  相似文献   
32.
目的:对中孕期非整倍体染色体异常血清学筛查不同方案的检出率进行探讨。方法选取513名2009年9月~2013年3月在攀枝花市妇幼保健院产科进行常规产前筛查的孕妇血清样本,分别采用化学发光法和时间分辨荧光免疫法对孕妇血清进行二联、三联、四联检查,比较阳性率及假阳性率。结果二联化学发光法检测唐氏综合征(DS)高危假阳性率为9.10豫,三联为7.36豫,四联为6.28豫,假阳性率呈递减趋势(字2=5.119,P约0.05);二联化学发光法筛查18-三体高危假阳性率(0.63豫)低于三联(0.82豫),差异有统计学意义(字2=4.776,P约0.05)。三联时间分辨荧光免疫法筛查DS、18-三体假阳性率(4.01豫、0.34豫)较二联(8.93豫、0.61豫)均明显降低(字2=6.992、4.776,P约0.05)。二联化学发光法检测DS、18-三体假阳性率分别为9.10豫、0.63豫,时间分辨荧光免疫法则分别为8.93豫、0.61豫,两种检测方法比较,差异无统计学意义(字2=1.787、0.000,P跃0.05);而三联时间荧光分辨法检测DS、18-三体假阳性率(4.01豫、0.34豫)均低于三联化学发光法(7.36豫、0.82豫),差异有统计学意义(字2=5.382、4.783,P约0.05)。结论化学发光法的检测系统发现筛查效率二联、三联及四联方案呈递增趋势。时间分辨荧光免疫法检测系统发现筛查效率三联高于二联方案,时间荧光分辨法三联筛查优于化学发光法。  相似文献   
33.
Einerhand  MP; Bakx  TA; Kukler  A; Valerio  D 《Blood》1993,81(1):254-263
An amphotropic retroviral vector, LgAL(delta Mo + PyF101) containing a human adenosine deaminase (ADA) cDNA was used to optimize procedures for the lasting genetic modification of the hematopoietic system of mice. The highest number of retrovirally infected cells in the hematopoietic tissues of long-term reconstituted mice was observed after transplantation of bone marrow (BM) cells that had been cocultured in the presence of both interleukin-1 alpha (IL-1 alpha) and IL-3. A significantly lower number was detected when IL-1 alpha was omitted from such cocultures. The yield of cells that generate spleen colony-forming cells (CFU-S) in the BM of lethally irradiated recipients (MRA-CFU-S) significantly improved on inclusion of the adherent cell fraction of cocultures in the transplant. Retroviral integration patterns in MRA-CFU-S-derived spleen colonies showed that an MRA-CFU-S can produce many CFU-S during BM regeneration. Expression of hADA was detected in the circulating white blood cells of long-term reconstituted animals, demonstrating that the LgAL(delta Mo + PyF101) vector is capable of directing the sustained expression of hADA, and in approximately 35% of the transduced MRA-CFU-S-derived spleen colonies. These results should facilitate the development of gene therapy protocols for the treatment of severe combined immunodeficiency caused by a lack of functional ADA.  相似文献   
34.
Correction for ‘Click chemistry approaches to expand the repertoire of PEG-based fluorinated surfactants for droplet microfluidics’ by Randall Scanga et al., RSC Adv., 2018, 8, 12960–12974.

The authors regret that during production of the published version of their article the bold formatting in the NMR data to indicate the nuclei of interest was lost. The correctly formatted Synthesis section of the Materials and methods is presented below.  相似文献   
35.
目的:了解孟根乌森乌日乐的急性毒性作用剂量及给药后的急性毒性反应和死亡分布情况,确定孟根乌森乌日乐的半数致死量( LD50)。方法用孔氏综合法(改进寇氏法)分为14.30,9.28,6.04,3.92,2.55,1.66 g? kg-16个剂量组,以0.4 mL/10 g的量灌胃给药1次。实验后观察14 d,记录体重变化及不良反应情况。结果孟根乌森乌日乐小鼠半数致死量为5.1597 g? kg-1(95%CI:3.6652~7.2637 g? kg-1)。14 d内未出现明显不良反应症状且体重有增长趋势。结论孟根乌森乌日乐的急性毒性实验的半数致死量为临床用药量的100倍,提示单次口服较为安全。  相似文献   
36.
目的比较5种布鲁氏菌核酸实时荧光PCR检测试剂盒的一致性和检出能力,为临床实验室选择检测方法和布鲁氏菌的诊断提供参考依据。方法选用经病原学检测确定为布鲁氏菌阳性的血液样本38份,健康人的血液样本24份,潘氏变形杆菌、溶藻弧菌、河弧菌、铜绿假单胞菌、肺炎克雷伯菌DNA各1份,使用5种试剂盒(编号A-E)分别进行核酸检测,比较5种试剂盒临床样本检测的一致性;选择1份阳性样本核酸用无RNA酶水梯度稀释得到5个浓度(浓度1:4453.13 fg/μL,浓度2:1113.28 fg/μL,浓度3:278.32 fg/μL,浓度4:69.58 fg/μL,浓度5:17.40 fg/μL),每个浓度使用5种试剂盒(编号A-E)分别进行3次检测,比较5种试剂盒的阳性检出率及批内重复性。结果5种试剂盒检测67份DNA样品的符合率稍有不同,试剂盒ABDE的符合率均为100%,试剂盒C的符合率为98.51%。批内重复性显示5种试剂盒在浓度1、浓度2、浓度3水平重复检测DNA的Ct值变异系数均<5%;在浓度1与浓度4梯度区间,试剂盒的阳性检出能力比较显示试剂盒A、B、D较高,为11/12,试剂盒C和E较低,为8/12。结论5种试剂盒的真实性和可靠性较好,灵敏度和符合率稍有差别,特异度均为100%;重复性较好,检测性能良好。部分试剂盒对弱阳性样本的检出能力不强,该类样本可使用多种试剂盒复核,以保障结果的准确性。  相似文献   
37.
The experimental metastatic potential (lung-colonizing ability) of B16BL6 melanoma cells was examined in C57BL/6 mice after exposure to ethanol in vitro and in vivo. In vitro, tumor cells were cultured with ethanol (0.3% v/v), or medium alone, for three passages at 5-day intervals. In vivo, B16BL6 melanoma was exposed to ethanol by administering ethanol (10% or 20% w/v) to mice following subcutaneous inoculation of tumor cells into the dorsal hip. All tumor cells were subsequently inoculated intravenously into the lateral tail vein of water-drinking mice to assess changes in metastatic phenotype. Tumor cells cocultured in vivo with ethanol produced significantly higher numbers of superficial lung colonies, compared with tumor cells cultured in control medium. Experimental metastasis of tumor cells obtained from 20% w/v ethanol-consuming mice was also significantly increased, compared with cells obtained from water-drinking mice. Metastasis of B16BL6 melanoma cells previously obtained from mice consuming 10% w/v ethanol did not differ from controls. In other experiments, water-drinking and ethanol-consuming (2.5%, 10%, and 20% w/v) mice were inoculated subcutaneously into the dorsal hip with B16BL6 melanoma cells, and monitored for tumor growth rate and survival time. In these experiments, survival times were significantly shorter in mice consuming 20% ethanol, compared with all other groups. Subcutaneous tumor growth rate was unaffected by ethanol consumption. Lung metastasis resulting from subcutaneous tumor implantation of B16BL6 melanoma was respectively inhibited, or absent, in 10% and 20% ethanol-consuming groups. Thus, tumor growth rate and incidence of lung metastases were not apparent determinants of decreased survival in 20% ethanol-consuming mice. The results of this study indicate that the experimental metastatic potential of B16BL6 melanoma is increased during exposure to ethanol; however, metastasis from subcutaneous tumor-bearing mice is suppressed. This latter finding is consistent with previous results in which spontaneous metastasis was also suppressed after inoculation of the tumor into the pinna of the ear. Although ethanol increases the ability of B16BL6 melanoma to colonize the lung after intravenous inoculation, this effect is abated in the presence of host factors in ethanol-consuming mice.  相似文献   
38.
To establish an in vivo model for the study of Hodgkin's disease and Reed-Sternberg (RS) cells, 25 lymph node tissue samples involved by Hodgkin's disease were grafted into severe combined immunodeficiency (SCID) mice. Ten Epstein-Barr virus (EBV)-associated tumors were obtained in SCID mice. EBV-positive tumors growing in SCID mice were correlated with the presence of EBV-positive nonneoplastic B cells in patient tumors (90% v 26.6%; P<.01) and was independent of the EBV status of RS cells. Our results suggested that EBV-positive tumors growing in SCID mice originated from normal EBV-positive small lymphocytes (bystander B lymphocytes). We also compared the characteristics of these tumors with those obtained after transplantation of 15 non-Hodgkin's lymphoma and four reactive lymph nodes. The latent period to observe a growing tumor in SCID mice was similar between the two groups (12.86 +/- 5.59 weeks for Hodgkin's disease v 13.6 +/- 5.36 weeks for non-Hodgkin's lymphoma and reactive lymph nodes). The relatively high number of EBV-positive small lymphocytes detected in Hodgkin's disease and T-cell lymphoma compared with B-cell lymphoma may account for the greater percentage of EBV- positive tumors obtained in SCID mice. Our results show that SCID mice do not provide the growth conditions that are required for in vivo growth of RS cells. We noted in some SCID tumors, the presence of binucleated and/or multinucleated giant cells resembling RS cells. However, the presence of such cells was not restricted to mice grafted with lymph nodes involved by Hodgkin's disease. We postulate that in previous reports, cells resembling RS cells were just binucleated EBV- positive lymphoma blastoid cells rather than actual RS cells.  相似文献   
39.
Journal of Artificial Organs - Veno-venous extracorporeal membrane oxygenation (ECMO) is typically instituted in severe respiratory failure, defined by Lung Injury Score, and caused either by...  相似文献   
40.
Asthma often starts before six years of age. However, there remains uncertainty as to when and how a preschool-age child with symptoms suggestive of asthma can be diagnosed with this condition. This delays treatment and contributes to both short- and long-term morbidity. Members of the Canadian Thoracic Society Asthma Clinical Assembly partnered with the Canadian Paediatric Society to develop a joint working group with the mandate to develop a position paper on the diagnosis and management of asthma in preschoolers.In the absence of lung function tests, the diagnosis of asthma should be considered in children one to five years of age with frequent (≥8 days/month) asthma-like symptoms or recurrent (≥2) exacerbations (episodes with asthma-like signs). The diagnosis requires the objective document of signs or convincing parent-reported symptoms of airflow obstruction (improvement in these signs or symptoms with asthma therapy), and no clinical suspicion of an alternative diagnosis. The characteristic feature of airflow obstruction is wheezing, commonly accompanied by difficulty breathing and cough. Reversibility with asthma medications is defined as direct observation of improvement with short-acting ß2-agonists (SABA) (with or without oral corticosteroids) by a trained health care practitioner during an acute exacerbation (preferred method). However, in children with no wheezing (or other signs of airflow obstruction) on presentation, reversibility may be determined by convincing parental report of a symptomatic response to a three-month therapeutic trial of a medium dose of inhaled corticosteroids with as-needed SABA (alternative method), or as-needed SABA alone (weaker alternative method). The authors provide key messages regarding in whom to consider the diagnosis, terms to be abandoned, when to refer to an asthma specialist and the initial management strategy. Finally, dissemination plans and priority areas for research are identified.  相似文献   
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