HIV感染者/AIDS患者血清基质金属蛋白酶-9表达与T细胞亚群的相关性研究

目的：了解艾滋病病毒(HIV)感染者及艾滋病(AIDS)患者血清中基质金属蛋白酶—9(MMP—9)水平表达及与T细胞亚群的相关性。方法：用酶联免疫吸附试验(ELISA)和流式细胞分析法，检测了18例HIV感染者和24例AIDS患者血清中MMP—9水平和淋巴细胞中CD3^ 、CD4^ 、CD9^ 的表达及绝对数。结果：HIV感染者组和AIDS患者组MMP—9水平较对照组明显升高(P＜0．05，P＜0.01)。AIDS患者组CD3^ 细胞数较对照组显著减少(P＜0．05)。HIV感染者组和AIDS患者组CD4^ 计数降低非常明显(P＜0．001)，CD8^ 计数非常明显升高(P＜0．00l，P＜0．01)，CD4^ ／CD8^ 的比值倒置。AIDS患者组MMP—9水平、CD3^ ，CD4^ 、CD8^ 的表达较HIV感染者组均有明显差异。HIV感染者组和AIDS患者组MMP—9表达与CD4^ 细胞数呈负相关(P＜0．05，P＜0．01)，AIDS患者组MMP—9水平与CD8^ 细胞数明显相关(P＜0．05)。结论:感染HIV后，MMP—9的水平随病情发展而增加，CD3^ 、CD4^ 细胞数逐渐减少，可作为判断AIDS患者疾病严重程度的指标。     

Development of day-8 colony-forming unit-spleen hematopoietic progenitors during early murine embryogenesis: spatial and temporal mapping

The ontogeny of the hematopoietic system in mammalian embryos occurs during the yolk sac (YS) and the fetal liver (FL) stages. Events leading to the establishment of hematopoiesis in the FL remain obscure. The appearance of colony-forming units-spleen (CFU-S) in the FL is preceded by a gradual increase of CFU-S in the YS and a more rapid increase in the AGM region (area comprising dorsal aorta, gonads, and mesonephros) during day 10 of development (Medvinsky et al, Nature 364:64, 1993). By this time, the AGM CFU-S attain a high frequency equivalent to that found in the adult bone marrow. The analogous area gives rise to adult hematopoiesis in amphibians and probably in birds. We present here a more complete picture of CFU-S development during transition from the pre-liver to liver stage of hematopoiesis. (1) Dissectional analysis of the mouse AGM region shows the presence of CFU- S both around the dorsal aorta and in the uro-genital ridges. (2) The embryonic gut also shows low but distinctive CFU-S activity. This initial intrabody pattern of CFU-S distribution in murine embryogenesis parallels that found for primordial germ cells. (3) The beginning of definitive liver hematopoiesis is accompanied by wide dissemination of CFU-S in the embryonic tissues. (4) Comparison of spleen colonies arising from the AGM and YS has shown morphologic differences. In contrast to simple erythroid constitution of the YS colonies, a broader variety of cells are found within the AGM-derived colonies that are similar to those derived from 11-day FL. These data suggest a lineage relationship for hematopoietic progenitors between the AGM region and the FL.     

Lymphangioma of the kidney

Lymphangiomas are rare benign tumors that are congenital malformations of the lymphatic system. Most cases present in children as a soft, cystic mass in the neck and the axilla. Primary renal lymphangioma is exceedingly rare, with only 35 cases reported so far. We report a case of primary lymphangioma arising from the kidney. A 59-year-old man was referred for evaluation of a right renal mass found in an abdominal ultrasonography during a health checkup. Abdominal ultrasonography and computed tomography (CT) revealed a 3.2 x 2.9 cm multiloculated cystic mass in the upper pole of the right kidney. We could not deny malignant disease such as cystic renal cell carcinoma with any diagnostic modalities. The patient was brought to surgery. During the surgical procedure, the tumor was suspected to be lymphangioma of the kidney as a result of a frozen- section histopathological evaluation. Therefore enucleation of the tumor was performed. Pathological evaluation of the specimen revealed lymphangioma arising from the kidney. The patient is free of disease after a 3-month follow-up period.     

The effect of ergothioneine on clastogenic potential and mutagenic activity: genotoxicity evaluation

L-(+)-ergothioneine has antioxidant and anti-inflammatory properties in vitro and in vivo and has uses as a dietary supplement and as an ingredient in foods, cosmetics, and as a pharmaceutical additive. The clastogenic potential and mutagenic of ergothioneine were assessed in vitro and in vivo. Ergothioneine concentrations up to 5000 μg/mL, with and without metabolic activation, was tested in the chromosome aberration assay with CHL cells and found not to induce structural chromosome aberrations. In the in vivo mammalian erythrocyte micronucleus test, ergothioneine was administered orally to male mice at doses up to 1500 mg/kg for potential genotoxic activity. No increase in the frequency of micronucleated polychromatic erythrocytes was observed. Overall, ergothioneine was not genotoxic in these studies and provides additional experimental evidence supporting the safety of its use as a potential dietary supplement.     

Effects of the histone deacetylases inhibitors sodium butyrate and trichostatin A on the inhibition of gap junctional intercellular communication by H2O2- and 12-O-tetradecanoylphorbol-13-acetate in rat liver epithelial cells

The histone deacetylase (HDAC) inhibitors, trichostatin A (TSA) and sodium butyrate (NaBu) are considered as potent therapeutic agents for cancer treatment presenting therapeutic benefits with less risk of side effects. The microbial metabolite, TSA is a potent reversible and highly specific inhibitor of mammalian histone deacetylases. NaBu causes hyperacetylation of core histones with effects similar to TSA but it is not a specific inhibitor of HDACs. The gap junction is a channel in the plasma membrane of most cell types which allows direct communication (gap junctional intercellular communication; GJIC) of small molecules and ions. Modulation of GJIC is a known cellular event associated with tumor promotion. The effects of NaBu and TSA on the H(2)O(2)- and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced GJIC inhibition of WB cells and the mechanisms involved in the process were assessed. TSA and NaBu exerted differential preventive effects on the H(2)O(2) and TPA-induced inhibition of GJIC as well as hyperphosphorylation of connexin43 (Cx43) in WB-F344 rat liver epithelial cells (WB cells). NaBu prevented the TPA-induced GJIC inhibition via ERK1/2 inactivation whilst TSA restored the H(2)O(2)-induced GJIC inhibition and Cx43 hyperphosphorylation by preventing p38 MAP kinase. The inhibition of tyrosine phosphorylation and down-regulation of src protein observed may also contribute to Connexin 43 dephosphorylation and GJIC restoration by TSA and NaBu partly through depletion of src protein pool. Thus, TSA and NaBu exert differential effects on chemically induced GJIC inhibition via modulation of MAP kinases and partly, tyrosine kinases.     

Comparative efficacy of oligonol, catechin and (-)-epigallocatechin 3-O-gallate in modulating the potassium bromate-induced renal toxicity in rats

Potassium bromate (KBrO(3)) is a by-product from ozonation of high-bromide surface water for production of drinking water and is a rodent carcinogen. Oligonol is a product emanating from the oligomerization of polyphenols, typically proanthocyanidin from a variety of fruits (grapes, apples, persimmons, etc.) and contains catechin-type monomers and proanthocyanidin oligomers. In this study, the ability of oligonol derived from grape seeds, grape seeds extracts (Product A, containing biologically active flavonoids and the oligomeric proanthocyanidin) and pine bark extracts (Product B, composed of flavan-3-ol derivatives) to modulate the KBrO(3)-induced renal toxicity was compared with (+) catechin and (-)-epigallocatechin 3-O-gallate (EGCG). In the Trolox equivalent antioxidant capacity (TEAC) assay, the order of the antioxidant activity was EGCG>catechin>oligonol>Product A>Product B. However, oligonol elicits the strongest antioxidant capacity following in vivo supplementation to rats, with the order of efficacy of oligonol>Product A> or =Product B>EGCG>catechin. Blood levels of lipid peroxidation products (LPO), urea nitrogen (BUN) and creatinine were elevated by KBrO(3) treatment. Oligonol significantly restored LPO to the level in the untreated rats and had the strongest potency when compared with the effects of Products A and B. The five materials lowered KBrO(3)-induced BUN level, but this was not statistically significant. Oligonol significantly reduced the increased level of the creatinine, seconded by Product A, Product B and EGCG. Catechin had the lowest effect in both the BUN and creatinine levels. That oligonol was able to modulate KBrO(3)-induced lipid peroxidation and the levels of blood urea nitrogen and creatinine suggests potential chemopreventive function and application in mitigating toxicity due to long-term exposure to KBrO(3) in public drinking water.     

The iron-binding and hydroxyl radical scavenging action of anti-inflammatory drugs

1. Hydroxyl radicals (.OH) are thought to be generated at sites of inflammation and to contribute to tissue damage. All anti-inflammatory drugs tested were able to scavenge .OH generated in free solution at almost diffusion-controlled rates (rate constants about 10(10)M-1s-1). 2. Much .OH generation in vivo occurs at specific sites, where bound metal ions (such as Fe2+) react with H2O2 to produce .OH that immediately attacks the site. Only .OH scavengers that have sufficient metal-binding ability to withdraw metal ions from this site can protect against site-specific damage. 3. All anti-inflammatory drugs tested were able to protect against site-specific damage by .OH in a simple model system in vitro. Penicillamine, diclofenac sodium, piroxicam, azathioprine, primaquine, chloroquine and hydroxychloroquine were especially effective. 4. The ability of an anti-inflammatory drug to protect against .OH formation in vivo depends not only on its rate constant for reaction with .OH, but also on its metal-binding ability and on the geometry and redox potential of any metal complex formed.     

Protection against oxidative damage and cell death by the natural antioxidant ergothioneine.

The natural antioxidant ergothioneine (EGT) was tested for its ability to inhibit cell death caused by hydrogen peroxide (H2O2) and to inhibit DNA oxidation by peroxynitrite (ONOO-) in human neuronal hybridoma cell line (N-18-RE-105). High concentrations of EGT (5 mM) were tolerated by the N-18-RE-105 cells. N-acetylcysteine (NAC) was not well tolerated by the cells at concentrations greater than 3 mM (cell viability averaged 50%). Increasing concentrations of EGT increases cell viability in the presence of NAC. EGT at concentrations up to 2 mM weakly improved cell viability in the presence of H2O2. NAC at concentrations up to 2 mM weakly decreased, but not significantly, the viability of the cells. At a higher concentration of 5 mM, NAC weakly protected the neuronal cells against the H2O2-induced cell death. The protection was significantly enhanced by preincubation with EGT. Ergothioneine inhibited ONOO(-)-induced oxidative damage in isolated calf thymus DNA and DNA in N-18-RE-105 cells. The concentration of EGT in human and mammalian tissue has been estimated to be 1-2 mM, which suggests that EGT may serve as a non-toxic thiol buffering antioxidant in vivo and may find applications in pharmaceutical preparations where oxidative stability is desired.     

Free radical scavenging and inhibition of lipid peroxidation by beta-blockers and by agents that interfere with calcium metabolism. A physiologically-significant process?

It has been proposed that beta-blockers and agents affecting Ca2+ metabolism might exert cardioprotective actions because of their ability to act as antioxidants in vivo. The feasibility of this proposal was tested by examining the reaction of a series of such compounds with various oxygen-derived species. None of the compounds tested was sufficiently reactive with superoxide radical, hydrogen peroxide or hypochlorous acid for scavenging of these species to be feasible in vivo at the drug concentrations present in patients given the usual therapeutic doses. All the drugs tested were powerful scavengers of hydroxyl radical except for flunarizine, which stimulated iron ion-dependent hydroxyl radical generation from hydrogen peroxide. However, none of the drugs significantly inhibited production of hydroxyl radicals in this system. Propranolol, verapamil and flunarizine had significant inhibitory effects on the peroxidation of rat liver microsomes in the presence of iron ions and ascorbic acid. All three compounds exerted weaker inhibitory effects on peroxidation of arachidonic acid caused by a mixture of myoglobin and H2O2: pindolol stimulated peroxidation in this system. It is concluded that the ability of beta-blockers and "Ca(2+)-blockers" to inhibit lipid peroxidation varies with the lipid substrate used and the mechanism by which peroxidation is induced. We conclude that suggestions that beta-blockers and "Ca(2+)-blockers" exert antioxidant effects in vivo are not well founded, although there is a possibility that verapamil and propranolol might have some inhibitory effects against peroxidation if they accumulate in membranes to a sufficiently-high concentration in vivo. We could not confirm the reported ability of propranolol to inhibit the enzyme xanthine oxidase.     

大鼠创伤性脑损伤后神经细胞凋亡的动态变化及其与caspase-3基因表达的关系

目的 探讨创伤性脑损伤(TBI)后神经细胞凋亡的变化规律及其与caspase-3基因表达的关系.方法 成年健康封闭群SD大鼠120只,随机分为对照组8只、损伤组和抑制物组各56只.Feeney法致伤,抑制物组伤后脑内注射5μg caspase-3抑制剂z-DEVD-fmk.分别在伤后1,6,24,48 h和3,7,14 d处死取材(每个分析时相点8只大鼠),采集伤灶中心皮质、皮层下白质、海马、齿状回,以及对侧相应部位脑组织,应用原位末端脱氧核糖核酸转移酶介导的脱氧尿苷三磷酸(dUTP)标记法(TUNEL法)和流式细胞术检测神经细胞凋亡的变化;免疫组化法、蛋白印迹(western blot)和半定量逆转录-聚合酶链式反应(RT-PCR),检测caspase-3蛋白和mRNA的表达;并借助荧光分析试剂盒检测caspase-3活性的变化.所得数据采用SIDSS 10.1统计软件包进行Sprarman等级相关分析和方差分析(sNK-α检验).结果 伤后伤侧各脑区神经细胞凋亡指数(AI)和细胞凋亡百分率(AP)迅速增高,24～48 h达峰值,随后逐渐下降,但伤后14 d仍高于正常(P＜0.01).伤后caspase-3蛋白和mRNA的表达明显增加,caspase-3活性迅速上升,峰值在24～48 h.其中伤后24 h伤侧海马区caspase-3蛋白谱密度与对照组相比增加1484%,caspase-3 mRNA的表达量增加1043%,caspase-3活性增加148%;伤后48h伤灶皮层下白质caspase-3蛋白谱密度增加1690%,caspase-3 mRNA的表达量增加1181%,caspase-3活性增加183%.Western blot显示,伤后caspase-3原酶及p17活性亚单位的表达均增强.抑制物组caspase-3蛋白和mRNA的表达均明显下降,caspase-3活性明显降低;同时,AI值和AP值也明显降低.统计学相关分析发现.伤后神经细胞凋亡与caspase-3 mRNA和蛋白的表达间呈正相关(r=0.821和r:0.638,P＜0.01),伤后caspase-3在mRNA和蛋白水平的表达间呈正相关(r=0.945,P＜0.01).结论 急性TBI后神经细胞凋亡的发生与caspase-3的激活有关;神经细胞凋亡与其调节基因caspase-3的表达间具有一致性,TBI对caspase-3的调节发生在转录水平前的某一环节.caspase-3抑制剂能有效地阻断TBI后的神经细胞凋亡.