血Tim-3联合γ-GT/胆碱酯酶比值在转氨酶正常或轻度升高慢性乙型肝炎患者中的临床价值

目的分析血T细胞免疫球蛋白黏蛋白3(Tim-3)联合[γ-谷氨酰转肽酶(γ-GT)/胆碱酯酶(CHE)](GCR)比值在转氨酶正常或轻度升高慢性乙型肝炎患者中的临床价值。方法选取109例转氨酶正常或轻度升高慢性乙型肝炎患者临床资料进行回顾性分析,绘制受试特征者工作(ROC)曲线探讨血Tim-3和GCR在转氨酶正常或轻度升高慢性乙型肝炎患者肝脏炎症分期和肝纤维化分级中的价值。结果109例CHB患者中,G140例、G230例、G326例、G413例;S144例、S232例、S320例、S413例。CHB患者肝脏炎症不同分期血Tim-3和GCR比较,差异有统计学意义(F=24.581,P=0.002;F=12.495,P=0.013);其中G2期患者血Tim-3为(16.09±3.57)ng/L,GCR为(1.04±0.29),高于G1期患者的(14.28±2.43)ng/L和(0.86±0.17),G3期患者血Tim-3为(18.65±4.81)ng/L,GCR为(1.26±0.38),高于G2期患者(P<0.05),G4期患者血Tim-3为(21.14±5.92)ng/L,GCR为(1.41±0.47),高于G3期患者(P<0.05);绘制ROC曲线分析发现,Tim-3和GCR均可预测肝脏炎症(≥G2)、(≥G3)和(G4)(P<0.05),但以Tim-3和GCR联合曲线下面积(AUC)最大(P<0.05)。CHB患者肝脏纤维化不同分期血Tim-3和GCR比较,差异有统计学意义(F=22.165,P=0.008;F=11.388,P=0.018);其中S2期患者血Tim-3和GCR高于S1期患者(P<0.05),S3期患者血Tim-3和GCR高于S2期患者(P<0.05),S4期患者血Tim-3和GCR高于S3期患者(P<0.05);绘制ROC曲线分析发现,Tim-3和GCR均可预测肝脏炎症(≥S2)、(≥S3)和(S4)(P<0.05),但以Tim-3和GCR联合曲线下面积(AUC)最大(P<0.05)。结论TIM-3和GCR均可预测转氨酶正常或轻度升高慢性乙型肝炎肝脏炎症和肝纤维化不同分期患者,尤以两者联合效能最高。     

The effect of polymorphisms of gamma-glutamyl hydrolase (GGH) gene on methotrexate-induced toxicity in acute lymphoblastic leukemia

Context: Acute lymphoblastic leukemia patients show differences in methotrexate-induced toxicity after treatment with this anti-cancer drug. Pharmacogenetics is an important determining factor for toxicity diversity. Objective: In this study, the effect of +452 CT and ? 401CT polymorphisms of Gamma-glutamyl hydrolase (GGH) gene on methotrexate serum levels and its associated toxicity in patients with acute lymphoblastic leukemia was assessed. Furthermore, the frequency of the above polymorphisms was investigated for the first time in Iran. Material and methods: The prevalence of these polymorphisms was assessed in 83 Iranian patients with ALL using PCR and RFLP. The relationship between the polymorphism and serum methotrexate levels and its toxicity was estimated by calculating the Odds Ratio. Results: No correlation was found between +452CT polymorphism and serum levels of methotrexate and methotrexate-related toxicity. ?401CT polymorphism was found to be correlated with methotrexate-related toxicity leading to thrombocytopenia (95% CI?=?0.009–0.019, odds ratio?=?0.265) and leukopenia (95% CI?=?0.021–0.042, odds ratio?=?2.182) in consolidation phase of the treatment. Discussion: C allele polymorphism of ?401?C/T allele is a risk factor of leukopenia and thrombocytopenia in patients treated with methotrexate. Moreover, our results suggested that the T allele had a supporting role in prevention of thrombocytopenia. Conclusion: Evaluation of patients for methotrexate-related polymorphism of GGH gene may be useful to determine the appropriate dose of methotrexate and reducing its toxic side effects.     

Structural basis for effectiveness of siderophore-conjugated monocarbams against clinically relevant strains of Pseudomonas aeruginosa

Pseudomonas aeruginosa is an opportunistic Gram-negative pathogen that causes nosocomial infections for which there are limited treatment options. Penicillin-binding protein PBP3, a key therapeutic target, is an essential enzyme responsible for the final steps of peptidoglycan synthesis and is covalently inactivated by β-lactam antibiotics. Here we disclose the first high resolution cocrystal structures of the P. aeruginosa PBP3 with both novel and marketed β-lactams. These structures reveal a conformational rearrangement of Tyr532 and Phe533 and a ligand-induced conformational change of Tyr409 and Arg489. The well-known affinity of the monobactam aztreonam for P. aeruginosa PBP3 is due to a distinct hydrophobic aromatic wall composed of Tyr503, Tyr532, and Phe533 interacting with the gem-dimethyl group. The structure of MC-1, a new siderophore-conjugated monocarbam complexed with PBP3 provides molecular insights for lead optimization. Importantly, we have identified a novel conformation that is distinct to the high-molecular-weight class B PBP subfamily, which is identifiable by common features such as a hydrophobic aromatic wall formed by Tyr503, Tyr532, and Phe533 and the structural flexibility of Tyr409 flanked by two glycine residues. This is also the first example of a siderophore-conjugated triazolone-linked monocarbam complexed with any PBP. Energetic analysis of tightly and loosely held computed hydration sites indicates protein desolvation effects contribute significantly to PBP3 binding, and analysis of hydration site energies allows rank ordering of the second-order acylation rate constants. Taken together, these structural, biochemical, and computational studies provide a molecular basis for recognition of P. aeruginosa PBP3 and open avenues for future design of inhibitors of this class of PBPs.     

胆淤指示酶升高程度在鉴别肝胆疾病黄疸中的价值

目的探讨胆淤指示酶升高程度在肝胆疾病黄疸鉴别诊断中的应用价值。方法根据黄疸的类型分为肝细胞性黄疸组和胆汁淤积性黄疸组,后者再分为肝内胆汁淤积组和肝外胆汁淤积组。分析血清总胆红素（TBIL）、直接胆红素（DBIL）、碱性磷酸酶（ALP）、γ-谷氨酰基转移酶（GGT）、丙氨酸氨基转移酶（ALT）、门冬氨酸氨基转移酶（AST）水平在肝细胞性和胆汁淤积性黄疸之间、以及肝内和肝外胆汁淤积之间分布的差异,并构建受试者操作特征（ROC）曲线。结果与肝细胞性黄疸组相比,胆汁淤积性黄疸组血清ALP与GGT水平显著升高,差异有统计学意义（P〈0.001）。根据ROC曲线计算血清ALP和GGT诊断胆汁淤积性黄疸准确度最高（特异度和敏感度之和最大）的临界值均为3×正常值上限（upperlimitofnormalvalue,ULN）,特异度和敏感度分别为94.29%和85.71%、92.38%和99.2%。在胆汁淤积性黄疸患者中,肝外胆汁淤积组血清GGT水平显著高于肝内胆汁淤积组,差异有统计学意义（P〈0.001）,血清ALP水平在两组间差异无统计学意义（P〉0.05）。血清GGT≥12×ULN时,诊断肝外胆汁淤积特异度和敏感度分别为90.63%和72.58%。结论血清ALP、GGT升高大于正常值上限3倍时有助于鉴别肝细胞性和胆汁淤积性黄疸,GGT明显升高更有助于肝外胆汁淤积的诊断。     

Liver function tests in patients with bacteremia

The purpose of this study was to evaluate liver function tests as potential indicators of bacteremia. We examined 156 patients with laboratory-confirmed bacteremia (bacteremia group) and 211 bacteremia-negative patients with bacterial infections (control group). The patients of the two groups had no underlying liver diseases. For patients in the bacteremia group, we analyzed liver function tests results obtained the day when the first positive blood culture was ordered. For those in the control group, the same data were obtained on the day when the first of multiple negative blood cultures was ordered. At t-test analyses, serum levels of gamma-glutamyl transpeptidase (gamma-GT) and alkaline phosphatase (ALP) were significantly higher, and those of albumin, total cholesterol, and cholinesterase were significantly lower in the bacteremia group than in the control group. Multivariate analyses found serum cholinesterase as an independent factor with adjusted odds ratio of 0.319 (per 65 U/L, standard deviation [SD] size). Serum level of C-reactive protein (CRP), on the other hand, showed no significant difference between the two groups. Serum levels of gamma-GT, ALP, albumin, total cholesterol, and cholinesterase more rapidly altered when various bacterial infections accompanied bacteremia. Therefore, they may be useful in detecting sepsis in its early stages.     

Protective effect of Ocimum sanctum on 3-methylcholanthrene, 7,12-dimethylbenz(a)anthracene and aflatoxin B1 induced skin tumorigenesis in mice

A study on the protective effect of alcoholic extract of the leaves of Ocimum sanctum on 3-methylcholanthrene (MCA), 7,12-dimethylbenzanthracene (DMBA) and aflatoxin B1 (AFB1) induced skin tumorigenesis in a mouse model has been investigated. The study involved pretreatment of mice with the leaf extract prior to either MCA application or tetradecanoyl phorbol acetate (TPA) treatment in a two-stage tumor protocol viz a viz, DMBA/TPA and AFB1/TPA. The results of the present study indicate that the pretreatment with alcoholic extract of the leaves of O. sanctum decreased the number of tumors in MCA, DMBA/TPA and AFB1/TPA treated mice. The skin tumor induced animals pretreated with alcoholic extract led to a decrease in the expression of cutaneous gamma-glutamyl transpeptidase (GGT) and glutathione-S-transferase-P (GST-P) protein. The histopathological examination of skin tumors treated with leaf extract showed increased infiltration of polymorphonuclear, mononuclear and lymphocytic cells, decreased ornithine decarboxylase activity with concomitant enhancement of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) in the serum, implying the in vivo antiproliferative and immunomodulatory activity of leaf extract. The decrease in cutaneous phase I enzymes and elevation of phase II enzymes in response to topical application of leaf extract prior to MCA, AFB1, DMBA/TPA and AFB1/TPA treatment indicate the possibility of impairment in reactive metabolite(s) formation and thereby reducing skin carcinogenicity. Furthermore, pretreatment of leaf extract in the carcinogen induced animals resulted in elevation of glutathione levels and decrease in lipid peroxidation along with heat shock protein expression, indicating a scavenging or antioxidant potential of the extract during chemical carcinogenesis. Thus it can be concluded that leaf extract of O. sanctum provides protection against chemical carcinogenesis in one or more of the following mechanisms: (i) by acting as an antioxidant; (ii) by modulating phase I and II enzymes; (iii) by exhibiting antiproliferative activity.     

Combined effects of alcohol and hepatitis C: A secondary analysis of alcohol use biomarkers and high-risk behaviors from two medication trials for alcohol dependence

Objectives

The goal of this secondary analysis was to examine the combined effects of HCV infection and recent alcohol use on baseline biologic markers of alcohol consumption in two outpatient medication trials for alcohol dependence. In addition, the relationship between Hepatitis C virus (HCV) infection and behavioral risk factors for HCV infection in these clinical populations were examined.

Methods

Data (n = 345) from two randomized, placebo-controlled trials of naltrexone and psychosocial treatment for alcohol dependence (Study I, n = 212) and comorbid alcohol and cocaine dependence (Study II, n = 133) were used to examine baseline measures of HCV risk behaviors (injection drug use, needle sharing), and biomarkers of alcohol use (AST, ALT, GGT and CDT) were compared by HCV serostatus first within each study and then across studies.

Results

Although groups had differing sociodemographic profiles (as indicated by race, marital status, level of education) subjects in Study I exhibited no statistically significant differences from the Study II cohort in HCV prevalence (12.7 vs. 20.0%, p = 0.07), lifetime history of injection drug use (13.8 vs. 22.0%, p = 0.74), lifetime history of needle sharing (9.1 vs. 18.0%, p = 0.62). As such, the data from both studies were analyzed together. Regardless of drinking status, HCV infection was significantly associated with an upward shift in the baseline level of ALT, AST, and GGT (p < 0.006 for all measures) and a downward shift in baseline CDT (p = 0.002). When using standard laboratory cutoff values to determine clinically significant elevations, HCV seropositivity was significantly associated with elevations in ALT, AST, GGT (p < 0.001), and with decreases in CDT (p = .002).

Conclusions

These data emphasize the importance of evaluating HCV infection and HCV risk behaviors at intake in medication trials for alcohol dependence and also raise questions regarding the use of cutoff scores for ALT, AST, GGT and CDT levels as biologic markers of alcohol use in subjects when HCV status is unknown.     

Alterations in copper homeostasis and oxidative stress biomarkers in women using the intrauterine device TCu380A

Copper ions participate in the Häber–Weiss reaction to produce ROS, which can be toxic when in excess. The purpose of this study was to measure the copper concentration (Cu) in the plasma of women using Cu-IUDs and determine (i) the effect of Cu on oxidative stress biomarkers, (ii) the levels of copper transport proteins in the plasma and (iii) the status of some liver damage markers in relation to the length of the intrauterine device use. Thirty-nine controls and 35 T380-IUD users were recruited. Various oxidative stress biomarkers, ceruloplasmin (CRP), metallothioneins (MTs), Cu and enzyme activities involved in liver function were measured in the plasma. The Cu concentration was higher in women with IUDs, concomitantly with time-dependent increases in the main oxidative stress biomarkers (TBARS, protein carbonyls, glutathione and nitrates + nitrites), hepatic enzymes (LDH and transaminases), MTs and CRP. We concluded that the use of Cu-IUDs for more than 2 consecutive years should be avoided in order to prevent oxidative damage.     

催化合成谷胱甘肽的基因工程菌的构建及表达

目的利用基因工程菌合成谷胱甘肽。方法克隆γ-谷氨酰转肽酶,构建重组质粒pET30a-GGT,乳糖诱导融合蛋白的表达,利用pET30a-GGT/E.coliBL21和pET32a-GSH-II/E.coliBL21分两步法合成γ-谷氨酰半胱氨酸与谷胱甘肽。结果工程菌的最佳乳糖诱导条件为:浓度3mmoL.L-1、时间6h、温度28℃。工程菌经最佳条件诱导后,γ-谷氨酰转肽酶的酶活大约是出发菌株E.coliDH5α的21倍,酶活力得到明显提高,谷胱甘肽的产量达到0.524g.L-1。结论成功地为今后利用基因工程菌催化合成谷胱甘肽寻找到一种新的方法 。