次黄嘌呤单核苷酸脱氢酶抑制剂对人外周髓样树突状细胞功能影响的研究

目的 探讨次黄嘌呤单核苷酸脱氢酶抑制剂(inosine monophosphate dehydrogenase inhibitor,IMPDHI)对人外周髓样树突状细胞(myeloid dendritic cells,MDC)功能的影响.方法 新鲜外周血单个核细胞(PBMC)来源于健康志愿者(n=15),实验组加入IMPDHI,流式细胞仪分析MDC表面共刺激因子、黏附分子、趋化因子受体等的表达水平.Transwell小室实验中,加入不同的趋化因子,经Lin-1/CD11c/HLA-DR染色后,流式细胞仪计数,以迁移细胞的百分比表示其迁移能力.分离血树突状细胞抗原-1+(blood dendritic cell antigen-1+,BDCA-1+)细胞,流式细胞仪测定BDCA-1+细胞中FTTC标记的右旋糖酐的荧光值.混合淋巴细胞培养后,流式细胞仪测定同种异体CD4+T淋巴细胞在G0期的比例.结果 细胞表面标志:与对照组相比,实验组MDC表面的CD40、CD62L、HLADR、CD54、CD80、CD83和CD86的表达水平明显下降(P＜0.05);趋化因子受体的表达水平:与对照组相比,实验组MDC表面的CCR1表达水平明显升高(17.02±3.23 vs 30.63±9.13,P＜0.05),CCR3的表达水平(10.26±2.25 vs 5.81±0.97,P＜0.05)和CCR7的表达水平(9.56±1.84 vs5.18±0.60,P＜0.05)明显下降;迁移功能:实验组MDC对趋化因子CCL2、CCL3、CCL4、CCL7、CXCL12的趋化能力明显增强(P＜0.05);吞噬能力:实验组MDC的吞噬能力明显强于对照组(P＜0.05);刺激同种异体CD4+T淋巴细胞增殖的能力:实验组中MDC诱导同种异体CD4+T细胞分裂、增殖的能力几乎完全受到抑制.结论 IMPDHI抑制外周MDC的成熟,增强其吞噬能力和炎性趋化的能力,抑制其刺激同种异体CD4+T淋巴细胞增殖、应答的能力.     

Changes in purines concentration in the cerebrospinal fluid of patients experiencing pain: A case-control study

This study analyzes the relationship between extracellular purines and pain perception in humans. Cerebrospinal fluid (CSF) levels of purines and their metabolites were compared between patients displaying acute and/or chronic pain syndromes and control subjects. The CSF levels of IMP, inosine, guanosine and uric acid were significantly increased in the chronic pain group and correlated with pain severity (P < 0.05). Patients displaying both chronic and acute pain presented similar changes in the CSF purines concentration (P < 0.05). However, in the acute pain group, only CSF inosine and uric acid levels were significantly increased (P < 0.05). These findings suggest that purines, in special inosine, guanosine and uric acid, are associated with the spinal mechanisms underlying nociception.     

甲状腺激素水平与移植肾功能关系的临床研究

目的 探讨肾移植受者的血清甲状腺激素水平与移植肾功能的关系.方法 57例肾移植受者根据移植后肾功能恢复情况分为移植肾功能恢复延迟(DGF)组(7例)和稳定组(50例).检测两组术前及术后不同时间的血清三碘甲状腺原氨酸(T3)、甲状腺素(T4)、促甲状腺素(TSH)和血清肌酐(Scr)水平.另检测30名健康志愿者的4项指标水平,作为正常对照.将稳定组术后第10天甲状腺激素水平与Scr水平进行相关性分析.结果 稳定组和DGF组术前血清T3、T4水平低于对照组(P＜0.01),而两组术前TSH水平与对照组相比较,差异无统计学意义(P＞0.05).稳定组与DGF组间术前各指标的差异无统计学意义(P＞0.05).稳定组术后第1天T3较术前下降约30％(P＜0.05),下降幅度大于其他指标,直到术后1周开始上升,术后2周接近正常水平,术后3周时已高于术前(P＜0.01);T4术后早期降低,10d后呈上升趋势,术后3周才接近术前水平;术后各时间段TSH水平与术前相比较,差异均无统计学意义(P＞0.05);Scr于术后7d恢复至正常水平.DGF组T3于术后21 d达到正常水平,T4于术后30 d达到术前水平;Scr于术后30 d达到正常水平.术后第10天,稳定组受者血清T3与Scr呈负相关(相关系数=0.546,P＜0.01),T4与Scr呈负相关(相关系数=0.423,P＜0.01).TSH与Scr无相关性.结论 T3、T4水平与移植后肾功能有相关性,要重视肾移植受者术后早期甲状腺功能状态及对受者恢复的影响.     

紫外分光光度法快速测定肌苷注射液中肌苷的含量

目的 本文建立一种肌苷注射液的紫外分光光度法含量测定。方法 以水为溶媒，检测波长在248nm的条件下，对肌苷注射液进行定量分析。结果 肌苷在浓度3μg-18μg范围内线性良好，以吸收系数法得其平均回收率为100.1%,RSD为0.9%。结论 结果表明该方法稳定可靠、简便、快速、重现性好。     

肌苷对脑缺血再灌流损伤神经功能恢复和NSE表达的影响

目的　观察大鼠脑缺血再灌流损伤脑组织神经元特异性烯醇化酶 (NSE)的变化规律及其意义 ;探讨肌苷对缺血性脑损伤的保护机制。方法　用成年 SD大鼠建立大脑中动脉缺血 (MCAO)再灌流模型 ,腹腔注射肌苷注射液 ,应用神经功能等级评分观察脑缺血再灌流后行为功能的恢复 ,免疫组化法检测脑缺血再灌流各时间点脑组织中 NSE的动态变化。结果　对照组脑缺血再灌流后 3d、7d、1 4 d功能恢复、等级评分减低 ;缺血侧 NSE的免疫阳性反应于脑缺血再灌流后 1 2 h明显增强并达高峰 ,随时间推移逐渐下降 ,至 1 4 d降至假手术组水平。治疗后神经功能评分在 7～1 4 d明显低于对照组 ,同时脑组织中 NSE蛋白表达水平较对照组显著升高。两组中皮层区 NSE的免疫阳性反应均高于纹状体区。结论　肌苷对缺血性脑损伤的功能恢复有一定的促进作用 ,其机制可能与增加脑组织中 NSE的表达有关     

An Index to Predict Ribavirin-Induced Anemia in Asian Patients With Chronic Genotype 1 Hepatitis C

Background:

Single-nucleotide polymorphisms (SNP) in the inosine triphosphate pyrophosphatase (ITPA) gene correlate with ribavirin (RBV)-induced anemia in patients with chronic hepatitis C (CHC) receiving combination therapy. Managing anemia is an early priority in the treatment process.

Objectives:

The aim was to develop a predictive index based on ITPA SNP status to identify CHC patients at risk of anemia.

Patients and Methods:

A total of 418 eligible East Asian patients diagnosed with CHC genotype 1 (G1) received combination therapy in this study. Participant DNA was genotyped for a functional ITPA SNP (C/C, A/A or C/A) on chromosome 20 at rs1127354. A predictive index was constructed by incorporating independent factors identified for severe anemia events (hemoglobin < 10 g/dL). Areas under the receiver-operating characteristic curves (AUCs) represented the diagnostic accuracies of the predictive index in randomly assigned development and validation cohorts.

Results:

Multiple logistic regressions identified age (≥ 50 y: OR = 9.7, 95% CI = 5.0 - 18.6), ITPA rs1127354 (C/C: OR = 3.3, 95% CI = 1.8 - 5.8) and baseline hemoglobin (< 14.0 g/dL: OR 6.4, 95% CI = 3.3 - 12.1; 14.0 - 14.9: OR = 2.4, 95% CI = 1.2 - 4.6) as predictors of severe anemia throughout the treatment. For severe anemia, the predictive index incorporating age, ITPA SNP status and baseline hemoglobin yielded diagnostic accuracies (AUCs) of 0.830 (95% CI = 0.783 - 0.871) in the development (n = 324) and 0.902 (0.826 - 0.925) in the validation (n = 81) cohorts.

Conclusions:

In patients with CHC G1 and receiving combination therapy, ITPA SNP-based index was an accurate and practical solution for prediction of severe anemia.     

Activation of adenosine A2 alpha receptors inhibits mast cell degranulation and mast cell-dependent vasoconstriction

OBJECTIVE: Adenosine and inosine accumulate in tissue during periods of ischemia and both molecules have been shown to degranulate mast cells in the hamster cheek pouch via activation of an A3 receptor. An A2-mediated inhibitory action of adenosine on mast cell degranulation has also been reported (16), and the objective of this research was to investigate the role of adenosine A2 receptors in modulating inosine-induced mast cell degranulation and subsequent vasoconstriction of microvessels. METHODS: Cheek pouches of the Golden hamster were prepared for in vivo microscopy. Adenosine, inosine, and other agents were applied either globally in the superfusion solution or to selected regions of the tissue by pipette. RESULTS: Micropipette application of 10(-4) M inosine to periarteriolar mast cells caused a vasoconstriction and an associated mast cell degranulation in 71% of the arterioles tested. The average diameter reduction was 29 +/- 5%. To establish a modulatory role for the A2 receptor, low doses of adenosine (100 nM and 10 nM) were applied globally via the superfusion prior to inosine stimulation. This adenosine pretreatment resulted in a decrease in the incidence of the inosine-induced vasoconstriction (17% and 31%), as well as smaller constrictions (0.5 +/- 1% and 7 +/- 3%). Mast cell degranulation was also reduced by pretreatment with adenosine, as evidenced by a decreased number of mast cells exhibiting ruthenium red dye uptake. The inhibitory effect of adenosine could be eliminated by pretreatment with the nonselective A1/A2 antagonist 8-(p-sulfophenyl) theophylline, which restored the inosine-induced responses to control values. To demonstrate that the effect was A2 alpha-mediated, vessels were pretreated with the selective A2 alpha agonist 2-[4-(2-carboxyethyl) phenethylamino]-5'-N-ethylcarboxamidoadenosine (CGS21680). Following this treatment, constriction in response to microapplication of inosine (10(-4) M) occurred in only 11% of the vessels tested; the average constriction was reduced to 2 +/- 2% and no mast cell degranulation was observed. CONCLUSIONS: We conclude that mast cell degranulation can be inhibited via activation of an adenosine A2 alpha receptor; which activation occurs at a lower concentration of adenosine than stimulatory A3 receptor activation. This finding may have implications for the pathology of ischemia.     

Recipient Pretransplant Inosine Monophosphate Dehydrogenase Activity in Nonmyeloablative Hematopoietic Cell Transplantation

Mycophenolic acid, the active metabolite of mycophenolate mofetil (MMF), inhibits inosine monophosphate dehydrogenase (IMPDH) activity. IMPDH is the rate-limiting enzyme involved in de novo synthesis of guanosine nucleotides and catalyzes the oxidation of inosine 5′-monophosphate to xanthosine 5′-monophosphate (XMP). We developed a highly sensitive liquid chromatography–mass spectrometry method to quantitate XMP concentrations in peripheral blood mononuclear cells (PMNCs) isolated from the recipient pretransplant and used this method to determine IMPDH activity in 86 nonmyeloablative allogeneic hematopoietic cell transplantation (HCT) patients. The incubation procedure and analytical method yielded acceptable within-sample and within-individual variability. Considerable between-individual variability was observed (12.2-fold). Low recipient pretransplant IMPDH activity was associated with increased day +28 donor T cell chimerism, more acute graft-versus-host disease (GVHD), lower neutrophil nadirs, and more cytomegalovirus reactivation but not with chronic GVHD, relapse, nonrelapse mortality, or overall mortality. We conclude that quantitation of the recipient's pretransplant IMPDH activity in PMNC lysate could provide a useful biomarker to evaluate a recipient's sensitivity to MMF. Further trials should be conducted to confirm our findings and to optimize postgrafting immunosuppression in nonmyeloablative HCT recipients.     

The biological activity in mammals and insects of the nucleosidic fraction from the spider Parawixia bistriata.

Previous work has shown that the crude venom of Parawixia bistriata induces convulsive seizures in rats after intracerebroventricular injection. In this work, the isolation of a bioactive fraction with ultraviolet absorption characteristics of nucleic acid and trace protein or amino acid content is described. NMR analysis demonstrated that the major component of the active fraction is the nucleoside inosine. An analogue of this component (inosine 5'-monophosphate) induced a delayed paralysis effect in termites.     

高效液相色谱法测定肌苷注射液中次黄嘌呤和鸟苷的含量

目的建立高效液相色谱法(HPLC)测定肌苷注射液中次黄嘌呤和鸟苷含量的方法。方法采用Shiseido Superiorex ODS色谱柱(4.6mm×250mm,5μm);以甲醇-水(10∶90)为流动相;流速1.0ml/min;检测波长248nm。结果次黄嘌呤的线性范围为0.05～5μg/ml,r=0.9999,最低检测限为8.5ng;鸟苷的线性范围为0.05～5μg/ml,r=0.9998,最低检测限为14.2ng。结论次黄嘌呤及鸟苷杂质峰与肌苷峰能达到有效分离,而且操作方法简便、准确、稳定,专属性强。该方法可用于肌苷注射液有关物质的检查。