新型重组人肿瘤坏死因子药代动力学的实验方法

目的 为探讨新型重组人肿瘤坏死因子（nrTNF α）药代动力学而建立生物样品中nrhTNFα的检测方法。方法 （1）方法Ⅰ（RA）：动物肌注^125 Ⅰ标记的nrhTNFα后，测定各生物样品中的总放射活性；（2）方法Ⅱ（HPLC－RA）；上述生物样品无经HPLC分离后，收集并测定其中^125Ⅰ－nrhTNFα部分的放射活性；（3）方法 ⅢELISA法。结果 RA，HPLC－RA法检测的nrhTNFα质量浓度与放射性呈直线相关（RA，r=0.999HPLC－RA,r=0.999)。ELISA法证明nrhTNFα的酶联免疫检测药盒适用于nrhTNFα的检测，nrhTNFα的标准曲线与nrhTNFα的标准曲线显正相关，r=0.994,这一检测系统与其他细胞因子包括IFNα，TNFβ，IL－2和IL－6无交叉反应。结论 RA，HPLC－RA和ELISA法均可作为nrhTNFα的药代动力学实验方法。     

α_2受体阻滞后肾上腺素诱导的心衰病人血小板的聚集功能

先前的研究表明血小板α_2受体变化表征交感神经突触前α_2受体的变化。为了解心衰病人血小板α_2受体功能状况,我们观察了10例Ⅲ、Ⅳ级心功能的心衰病人及10例配对正常人由肾上腺素诱导的血小板聚集率在α_2受体阻滞前后的变化。结果表明肾上腺素诱导的血小板聚集率在两组无显著性差异,但应用α_2阻滞剂Rauwolscine(0.25mg/L)后,0.25,0.5,1.0mg/L E诱导的心衰病人血小板聚集率显著低于对照组,提示血小板α_2受体在心衰时有数量的减少或(和)功能的降低,表征交感神经突触前NE释放的负反馈机制被抑制。     

Autonomic control of acid phosphatase exocrine secretion by the rat prostate

Summary In vivo prostatic secretion was collected from retired breeder Sprague Dawley rats using a method for isolated perfusion of the rat prostatic urethra. Enzymatic acid phosphatase determination was performed on the collected effluent. Control acid phosphatase secretion was 24.2±2.7 nm over 30 minutes. Intravenous phenylephrine 5 mg/kg stimulated a 10 fold increase in acid phosphatase secretion. The secretion seen with phenylephrine was dose dependent and could be blocked with prazosin, but not yohimbine, atropine, or propranolol. Intravenous -adrenergic agonist isoproterenol caused no increase in the secretion of rat prostatic acid phosphatese. Intravenous administration of the cholinergic agonist pilocarpine also resulted in a dose dependent rise in acid phosphatase secretion. The stimulation seen could be blocked by atropine but not phentolamine or propranolol. The stimulation of acid phosphatase secretion seen with ₁ adrenergic or cholinergic agonists was not additive. Intravenous vasoactive intestinal peptide did not stimulate acid phosphatase secretion nor did it augment the secretion induced by ₁ adrenergic or cholinergic agonists. Release of acid phosphatase into rat prostatic exocrine secretion is under both ₁ adrenergic and cholinergic control.Supported by the US Veterans Administration     

Natural killer cells and reproductive failure--theory, practice and prejudice

The relationship between peripheral blood natural killer (NK) cells and reproductive failure is one of the most controversial areas in reproductive medicine. Amidst much publicity, peripheral blood NK cell testing is being promoted as a useful diagnostic test to guide the initiation of a variety of immunosuppressive therapies amongst patients with either recurrent miscarriage or infertility. We contend (i) that at present there is no scientific basis for the introduction of NK cell testing into routine clinical practice, and (ii) that the use of immunosuppressant agents based on the results of such testing may potentially be harmful.     

Osteopontin affects the persistence of beta-glucan-induced hepatic granuloma formation and tissue injury through two distinct mechanisms

Osteopontin (OPN) plays a pivotal role in various immune responses and inflammatory diseases. OPN is expressed in various granulomatous diseases; however, the cellular and molecular role of OPN in these diseases is not well known. We analyzed the role of OPN in a beta-glucan-induced hepatic granuloma model. First, we found that neither OPN deficiency nor overexpression of OPN affected the number and the size of hepatic granulomas at day 7, indicating that OPN is not involved in the formation of hepatic granulomas at the early stages. Importantly, OPN did not influence the liver tissue damage as defined by alanine aminotransferase and aspartate aminotransferase levels at early stages. Second, OPN deficiency resulted in the reduction of IL-12 and IFN-gamma production at early stages. Third, at late stages, OPN deficiency resulted in a decrease in the number and size of hepatic granulomas, and a reduction of liver tissue injury. This was due to the reduction of the cellular recruitment including macrophages, CD4 T cells and dendritic cells into the liver, and the reduction of tumor necrosis factor (TNF)-alpha production in the liver. In contrast, overexpression of OPN resulted in the persistence of granuloma formation. These data suggest that OPN affects the persistence of hepatic granuloma formation. Our results indicate that OPN up-regulates the production of IL-12 and IFN-gamma within the granulomas at early stages, and OPN has an additional role in the regulation of cellular recruitment and TNF-alpha production at late stages that determine the severity of liver tissue injury.     

Effect of inhaled corticosteroid on an immunoreactive thymus and activation-regulated chemokine expression in the bronchial biopsies from asthmatics

BACKGROUND: Bronchial asthma is characterized by airway inflammation, notably because of eosinophils and T cells. Thymus and activation-regulated chemokine (TARC) is known to selectively attract Th2 cells, and is increased in response to interleukin (IL)-4 and IL-13, which share a common receptor, IL-4 receptor alpha (IL-4Ralpha). While corticosteroids have proven, very effective in modifying airway inflammation, the effect of corticosteroids on TARC in asthmatics has been little studied. OBJECTIVE: We examined the effects of inhaled budesonide (BUD) on the expression of TARC and the number of inflammatory cells in bronchial biopsy specimens taken from asthma patients. METHODS: Inhaled BUD 800 mug daily, or placebo was administered for 3 months in a double-blind, parallel-group study, and bronchial biopsies were performed before and after treatment. Biopsy specimens were examined by immunocytochemistry. RESULTS: We observed a significant decrease in the epithelial expression of TARC (P < 0.01) in the BUD group compared with the placebo group. This was accompanied by decreases in the number of eosinophils (P < 0.01), CD3(+) T cells (P < 0.05), and CD4(+) T cells (P < 0.01). A significant correlation was found between changes in epithelial TARC and in IL-4Ralpha immunoreactivity (r(s) = 0.66, P < 0.01). CONCLUSIONS: These findings suggest that corticosteroid asthma treatment can reduce infiltration of the airway by inflammatory cells, an effect modulated by down-regulation of bronchial epithelial TARC expression.     

Inhibition of HIV-1 by modification of a host membrane protease

While it is clear that CD4 Is the receptor for the gp120 envelopeprotein of HIV-1, substantial evidence suggests that other hostcell proteins are required for successful membrane fusion. Studieswere initiated to examine the potential for a protein receptorwhich has an elastase-like character to participate in fusionof HIV-1 with permissive host cells. A synthetic elastase inhibitorwas shown to significantly reduce HIV-1 infectivity when presentduring, but not after, the initial contact between virus andcells. A human T cell elastase-like membrane component was purifiedand shown to be lipid-associated. By competitive Inhibition,the purified protein was shown to bind gp160 within the HIV-1fusion domain. The binding parameters of whole T cell membraneextract, with a hydrophobic pentapeptide representative of thefusion domain, suggested an elastase-like protein is the single,secondary T cell receptor for HIV-1 (K = 1x10³ M^–1). Thepentapeptide interacted with porcine and human (epithelial andpolymorphonuclear leukocyte), but not murine, elastase isoforms,suggesting its participation In the permissiveness of host cellsto infection.     

Signal transduction in human B cells initiated via Ig{beta} ligation

Ig and Igß heterodimers are non-covalently associatedwith Ig to compose the antigen receptor complexes on B cells.The demonstration that different sets of tyrosine kinases bindto the cytoplasmic tails of Ig and Igß suggests thatIg and Igß may activate distinct second messengerpathways. In this study, we examined the effects of mAbs againstan exposed epitope of human Igß on pre-B and B celltriggering. Cross-linkage of Igß on B cells leadsto activation of tyrosine kinases, hydrolysis of phosphatidylinositides,and elevation of intracellular Ca²⁺, effects qualitatively identicalto those of anti-_µ mAbs. Our observations thus indicatethat cross-linking of Igß does not segregate signaltransduction pathways connected with the cytoplasmic talls ofIg and Igß. Ig ligation has been reported to be moreeffective in triggering pre-B than B cells, whereas our resultsindicated that Igß ligation is more efficient in triggeringB than pre-B cells. In addition to their activation properties,the anti-Igß mAbs effectively modulated B cell receptorcomplexes and blocked terminal differentiation of all plasmacell isotypes. The findings support the idea that anti-Igßcould serve as a universal B cell immunosuppressant.     

Investigation of the role of the serotonergic activity of certain subtype-selective alpha1A antagonists in the relaxant effect on the pregnant rat uterus in vitro

Results from recent studies have shown that alpha(1A)-adrenergic receptor (alpha(1A)-AR) antagonists could offer a new alternative in the treatment of preterm delivery. However, members of this group [2-(2,6-dimethoxyphenoxyethyl)aminomethyl-1,4-benzodioxane hydrochloride (WB4101), 5-methylurapidil (5-MU)] are known to influence serotonin (5-hydroxy-tryptamine) (5-HT(1A)) receptors, too. Our objective was to clarify the role of their 5-HT(1A) activities in the uterus relaxant effect. RT-PCR was used to determine mRNA expression of the receptor subtypes in 22 day pregnant rat uteri. Isolated uteri were stimulated by 5-HT or electrical field to investigate the contraction-inhibiting effect and the 5-HT(1A) activity of the alpha(1A) antagonists. Both receptor subtypes are present in rat myometrium. 5-HT induced contractions were inhibited by the alpha(1A) antagonists. Besides shifting the dose-response curve of 5-HT to the right, 5-MU decreased its maximal effect. The alpha(1A) antagonists inhibited electrical field stimulation-induced contractions. 5-HT(1A) blockade increased the maximal effect of 5-MU but did not change that of WB4101. These results suggest that the contraction increase caused by 5-HT is mediated by alpha(1A) receptors. Serotonergic activity of alpha(1) antagonists and especially alpha(1A) antagonists should be investigated as it may alter their efficacy and could interfere with their side-effects. It is proposed that novel alpha(1A) antagonists should be designed with no 5-HT(1A) activity to achieve maximal relaxant effect.     

一种新的土拨鼠α干扰素基因分型方法的建立及其意义

目的：建立新的土拨鼠α干扰素（IFN-α）基因分型方法，分析急性和慢性土拨鼠肝炎病毒（Woodchuck hepati-tis virus，WHV）感染的土拨鼠肝细胞中不同型别的IFN-α基因表达谱及其意义。方法：利用已知序列和基因型的土拨鼠IFN-α基因克隆质粒，建立基于土拨鼠IFN-α基因序列的限制性片段长度多态性的土拨鼠IFN-α基因分型方法。PolyIC体外刺激正常土拨鼠外周血单个核细胞（PBMC），调查正常土拨鼠PBMC受PolyIC刺激后IFN-α基因的表达谱。提取急性和慢性土拨鼠肝炎病毒感染的土拨鼠肝组织mRNA，RT-PCR扩增土拨鼠IFN-α基因，分子克隆后调查急性和慢性感染的土拨鼠肝细胞中IFN-α基因表达谱。结果：建立了土拨鼠IFN-α基因限制性片段长度多态性分型方法。急性和慢性感染的土拨鼠肝细胞中IFN-α基因的表达谱明显不同于正常动物的表达谱，假基因表达所占比例大。结论：新建立的土拨鼠IFN-α基因分型方法可用于分析土拨鼠不同组织中IFN-α的基因表达谱。