Effects of MEK on kinetics ofn-hexane metabolites in serum

The neurotoxicity ofn-hexane is thought to be caused ultimately by 2,5-hexanedione (2,5-HD), one of then-hexane metabolites. The potentiation ofn-hexane neurotoxicity by co-exposure with MEK, therefore, is suspected to be related to kinetics of 2,5-HD in blood. To clarify the kinetics ofn-hexane metabolites in the mixed exposure ofn-hexane and MEK, rats were exposed to 2000 ppmn-hexane or a mixture of 2000 ppmn-hexane and 2000 ppm MEK, and the time courses of serumn-hexane metabolites were determined. 2,5-HD in serum increased until 2 h after the end of exposure, when serum 2,5-HD concentration reached a peak of 16.35 g/ml in then-hexane-alone group. In contrast, 2,5-HD in the mixed exposure group increased much more slowly during and after exposure than in then-hexane-alone group. It reached a peak of 2.12 g/ml at 8 h after the end of exposure. Serum MBK, a precursor of 2,5-HD in the co-exposure group, was about half in then-hexane-alone group during exposure. However, MBK decreased more slowly in the co-exposure group than in then-hexane-alone group after the end of the exposure. The results suggest that co-exposed MEK might inhibit oxidation ofn-hexane and decrease clearance ofn-hexane metabolites. Co-exposed MEK did not increase serum 2,5-HD, which was considered a main neurotoxic metabolite. Therefore the enhancement of neurotoxicity could not be attributed to increased serum 2,5-HD in the co-exposed group. The mechanism of enhancement of neurotoxicity ofn-hexane by MEK should be studied further.     

Stress-induced reduction in the rat mixed lymphocyte reaction is due to macrophages and not to changes in T cell phenotypes

Exposure to aversive events or Stressors modulates various aspects of immune function. We have previously reported that exposure to an acute Stressor, inescapable tail shock (IS), resulted in a shift in T cell subpopulations in rat mesenteric lymph nodes but not in cervical lymph nodes (Fleshner et al. (1992) J. Neuroimmunol. 41, 131–142). The mesenteric ratio was increased immediately after exposure to IS and was due primarily to an increase in the percent of CD4⁺ cells. The present experiments were designed to determine the relationship between the IS-associated phenotypic shift and its significance in the function of CD4⁺ T cells. The function assessed was the in vitro proliferative response to alloantigens coded for by the Major Histocompatibility Complex (MHC). Using the mixed lymphocyte reaction (MLR), we report that exposure to IS resulted in a decrease in the MLR response of cells from both cervical and mesenteric lymph nodes. Depletion of macrophages (nylon wool adherent cells) eliminated the IS-induced reduction and co-culture of macrophages (irradiation-insensitive cells) from shocked rats produced the suppression. One interpretation of these data is that exposure to IS resulted in the activation of macrophages and the release of a suppressive factor which reduced the MLR response of peripheral lymph node lymphocytes.     

L—脯—L—亮—甘氨酰胺的合成

三肽,Ｌ－脯－Ｌ－亮－甘氨酰胺是促黑激素释放抑制因子（ＭＩＨ）具有多方面的生理药理作用,ＰＬＧ的合成是通过碳二亚胺法和混和酸酐法将叔丁氧羰基脯氨酸、叔丁氧在亮氨城氨酸乙酯缩合之后地由氨气氨解,并经三氟醋酸脱保护基。最终产物的由元素分析、质谱、熔点及旋光度的测定得以证实。     

长沙地区汉族人群红细胞EsD和PGM1的分布研究

本文采用琼脂糖、水解淀粉混合凝胶电泳法同时分析血液EsD、PGM1二种酶型。调查了这二种酶的表型分布和基因频率及其识别能力 ,并与不同地区、不同国家和不同民族进行比较研究。此法可用于个人识别和亲权鉴定     

Likelihood ratios for mixed stains when the number of donors cannot be agreed

Suppose that part of the prosecution's evidence in some crime case is analysis of a blood stain, and that the traits E discovered in the stain suggest multiple donors. Then the prosecution will probably allege some specific inculpatory hypothesis H₀ about the sources of the stain, and P {E | H₀} can be calculated. It is desirable to use this as the numerator of a likelihood ratio. However, in general the obvious denominator P {E | H₀} cannot be calculated, so unless the defense is sufficiently obliging as to stipulate to a specific choice among the potentially infinite number of more or less exculpatory alternative hypotheses, the desired likelihood ratio can't be evaluated. We show that nonetheless, in most cases there is an adequate inequality.     

The effect of recombinant human growth hormone on responses to alloantigens in the pediatric transplant patient

Recombinant human growth hormone (rhGH) improves growth in children after renal transplantation, but may be associated with augmented immune responses. We previously demonstrated that rhGH augments proliferative and cytotoxic responses and interferon-gamma (IFN-) mRNA expression during a mixed leukocyte culture (MLC). In this study, we evaluated 12 pediatric patients after receiving a renal allograft from one of their parents. Peripheral blood mononuclear cells (PBMC) were isolated from patients and cultured with either donor or unrelated third-party PBMC in an MLC. Patients developed significant donor-specific hyporesponsiveness (DSH), however, no correlation was seen between the amount of DSH and graft function. Of the 12 patients, 2 developed augmented responses in the presence of rhGH. rhGH augments proliferation, cytotoxicity, and IFN- expression during an MLC. Some patients develop increased responses to donorspecific alloantigens after renal transplantation. Further study is needed to better determine the significance of this finding.     

卵巢恶性中胚叶混合瘤12例临床分析

目的探讨卵巢恶性中胚叶混合瘤的临床特点、治疗及预后因素。方法对我院１９８３年～１９９７年收治的１２例卵巢恶性中胚叶混合瘤的临床资料进行回顾性分析。按ＦＩＧＯ分期（１９８５年）,Ⅱ期４例,Ⅲ期６例,Ⅳ期１例,不详１例。组织学分类：同源性８例,异源性４例。１２例均接受肿瘤细胞减灭术。术后辅助化疗１１例,其中３例又追加盆腔放疗。结果全组平均生存２４个月,２,５年生存率分别为３３．３％（４／１２）和８．３％（１／１２）。Ⅱ和Ⅲ期生存２年以上者均为２例,Ⅳ期１例在１年内死亡。同源性８例中,４例生存２年以上,异源性４例均在２年内死亡。综合治疗１１例中,５例在１年内死亡。单纯手术１例在６个月内死亡。结论卵巢恶性中胚叶混合瘤恶性度高,预后差。其组织学类型、分期及治疗方法与预后有关,应采用手术与化疗和（或）放疗的综合治疗     

Genetic Alterations of Mixed Hyperplastic Adenomatous Polyps in the Colon and Rectum

Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs.     

地高辛、维生素B1混合粉末在常温下的稳定性考察

目的：研究地高辛与维生素B1混合粉末在常温下的稳定性。方法：在25℃条件下，采用紫外分光光度法，测定其含量、重量在10、20、30、40、50天的变化情况。结果：在25℃下，混合粉末在30天前基本稳定。结论：地高辛、维生素B1混合粉末保存不应大于30天。     

混合血清检测在寄生虫病血清流行病学调查中的应用

目的 通过旋毛虫病、弓形虫病血清学检测，探讨了混合血清检测（混检）在寄生虫病血清流行病学调查中的应用及对成本-效果的影响。方法 根据二项分布原理，探讨混合血清检测的可行性。旋毛虫病或弓形虫病血清学检测，采用3、5、10份等三种混检方法。同时对血清样品逐一检测和混合检测进行了成本-效果评价。结果 只要混有1份弱阳性血清，旋毛虫病或弓形虫病的三种混检都呈阳性结果。如果混合的血清全部是阴性，旋毛虫病3、5、10份阴性血清样品混合各检测24组，全部呈阴性；弓形虫病3、5份阴性血清样品混合，检测12组，都呈阴性，10份阴性血清样品混合，检测18组中16组呈阴性，2组呈阳性。旋毛虫病或弓形虫病混检显示，混检效率与待检寄生虫血清学阳性率有关，血清学阳性率在10％时，4份混检效率较高，血清学阳性率在1％时，以10份混检效率较高，而当血清阳性率在0．1％时，增加混检样品数可明显减少检测次数，但前提条件是要保证混检样品中只要有1份阳性样品，混检时都能测出阳性，而且若全部是阴性样品混检，也不出现阳性。结论 运用卫生经济学成本-效果分析，表明寄生虫病血清流行病学调查，混检成本低，尤其是对预期血清学阳性率较低（≤1％）的调查，混检可节省大量成本。