三磷腺苷二钠注射液细菌内毒素检查法研究

目的 :研究三磷腺苷二钠中细菌内毒素的检查方法。方法 :通过干扰试验证明三磷腺苷二钠注射液对细菌内毒素检查有抑制作用。结果 :三磷腺苷二钠注射液经一定稀释后对测定无干扰。结论 :细菌内毒素检查法简单、可行 ,适用于检查该注射液。

三磷腺苷二钠氯化镁与果糖注射液合用致发热1例

1病例报告患者男,94岁。因反复头晕20余年,加重1周入院。查体：体温36.8℃,脉搏87/min,呼吸20次/min,血压140/70mmHg。实验室检查：白细胞计数7.9×109/L、血红蛋白127g/L、血小板计数95×109/L,尿粪常规、电解质及凝血因子正常。头颅CT检查示老年性脑萎缩、多发腔隙性脑梗死。诊断为脑动脉硬化。入院后给予抗感染、扩张血管、利尿、改善循环等常规治疗,效果良好。

氯吡格雷对早期急性冠状动脉综合征血清sCD40配体的影响

目的观察用氯吡格雷(clopidogrel)治疗早期急性冠状动脉综合征(acute coronary syndrome,ACS)对病人血清可溶性CD40配体(soluble CD40ligand,sCD40L)的影响,了解该药对ACS斑块稳定性和免疫炎症抑制的作用。方法128例初次确诊为ACS病人分为常规治疗组62例和氯吡格雷治疗组66例,用酶联免疫吸附测定ACS病人治疗前后血清sCD40L水平的变化。结果氯吡格雷治疗组66例ACS病人治疗后血清sCD40L水平从(11.8±3.1)μg/L下降至(5.7±3.0)μg/L,与常规治疗组比较,差异有统计学意义(P<0.01)。结论使用氯吡格雷治疗早期ACS,可明显降低病人sCD40L水平。

蛇毒试剂诱导血小板聚集实验的观察

目的：观察新型血小板聚集诱导剂蛇毒试剂（plateletaggre-gationvenomreagent,PAgVR）对血小板聚集的作用特点。方法：用血小板聚集仪观察PAgVR诱导不同疾病状态下的血小板聚集情况，并以二磷腺苷（ADP）作对照、结果：在高脂血症病人PAgVR（12．5mg／L）诱导血小板聚集率增高，作用强度与二磷腺苷（2μmol／L）相近（P＞0．05）；在慢性肾炎尿毒症和失代偿性肝硬化患者，PAgVR诱导血小板聚集的作用强度明显高于二磷腺苷（P＜0．05）．结论：在不同疾病状态下，PAgVR和二磷腺苷诱导血小板聚集的作用强度存在差异．在临床应用尤其是对某些低凝倾向病人进行检测时应引起注意。

氯吡格雷更换为替格瑞洛抗血小板聚集疗效的前后对比

目的探讨急性冠脉综合征患者氯吡格雷更换为替格瑞洛抗血小板聚集疗效的前后对比。方法选取2018年4~11月北京大学国际医院收治的31例急性冠脉综合征患者作为研究对象,所有患者采用氯吡格雷治疗后接受血栓弹力图二磷酸腺苷(ADP)抑制率检测(A阶段数据),然后停用氯吡格雷更换为替格瑞洛治疗后再次检测血栓弹力图ADP抑制率(B阶段数据),对比前后两次检测ADP抑制率的结果。将氯吡格雷更换为替格瑞洛后行血栓弹力图ADP抑制率检测,按照该检测的采血时间点距离最后1次服用氯吡格雷的时间间隔分为三组,第一组(24~<36 h),第二组(36~<96 h),第三组(≥96 h)。比较三组的一般资料和A、B阶段血栓弹力图ADP抑制率,并对其中24例患者行CYP2C19基因型检测。结果三组B阶段的血栓弹力图ADP抑制率均高于本组A阶段血栓弹力图ADP抑制率,差异有统计学意义(P<0.05)。24例行CYP2C19基因型检测的患者中(CYP2C19*1/*1)正常代谢型17例,17例中有10例(58.8%)服用氯吡格雷后ADP抑制率<30%,但这10例患者更换为替格瑞洛后ADP抑制率9例均升至50%以上。结论氯吡格雷更换为替格瑞洛具有更好的抗血小板聚集疗效,急性冠脉综合征患者服用替格瑞洛具有更好的抗血小板聚集的疗效,即使是基因正常代谢型的患者也可能存在氯吡格雷抵抗,更换为替格瑞洛后抗血小板聚集疗效好转。

High prevalence of aspirin resistance in elderly patients with cardiovascular disease and metabolic syndrome

Background Metabolic syndrome is known to be a prothrombotic state. We undertook this study to examine a hypothesis that aspirin resistance may be associated with metabolic syndrome, and to assess other potential determinants of aspirin resistance in patients with cardiovascular disease （CVD）. Methods A total of 469 elderly patients with CVD were recruited. One hundred and seventy-two patients with metabolic syndrome and 297 without metabolic syndrome （control group） received daily aspirin therapy （〉 75 mg） over one month. Platelet aggregation was measured by light transmission aggregometry （LTA）. Aspirin resistance was defined as 〉 20% arachidonic acid （AA）- and 〉 70% adenosine diphosphate （ADP）-induced aggregation according to LTA. Aspirin semi-responders were defined as meeting one （but not both） of these criteria. Results By LTA, 38 of 469 （8.1%） patients were aspirin resistant. The prevalence of aspirin resistance was higher in the metabolic syndrome group compared with the control group [11.6 % vs. 6.6%, odds ratio （OR） = 2.039; 95% confidence interval （CI）： 1.047-3.973]. In the multivariate logistic regression analysis, metabolic syndrome （OR = 4.951, 95% CI： 1.440-17.019, P = 0.011） was a significant risk factor for aspirin resistance. Conclusions A significant number of patients with CVD and metabolic syndrome are resistant to aspirin therapy. This might further increase the risk of cardiovascular morbidity and mortality in these patients.

Thymidylate synthase and thymidine phosphorylase gene expression as predictive parameters for the efficacy of 5-fluorouraci-based adjuvant chemotherapy for gastric cancer

AIM： To investigate the prognostic role of thymidylate synthase （TS） and thymidine phosphorylase （TP） mRNA levels in T3 or T4 gastric cancer treated with 5-fluorouraci-based adjuvant chemotherapy. METHODS： Fifty-one patients with T3 or T4 gastric cancer received systemic 5-fluorouraci-based adjuvant chemotherapy, and intratumoral expression of TS and TP in 51 gastric cancer tissue samples was tested by realtime quantitative PCR.RESULTS： The median disease-free survival （DFS） time was 10.2 mo in the patients. There were no significant differences in DFS between the groups with high and low levels of TP. However, the group with low level of TS had a longer DFS （14.4 mo vs 8.3 mo, P = 0.017）. The median overall survival （OS） time was 18.5 mo, and there were significant differences in OS between the groups with high and low levels of TS or TP （for TS, 17.0 mo vs 21.3 mo, P = 0.010; for TP, 16.6 mo vs 22.5 too, P = 0.009）. Moreover, the coupled low expression of these two genes was strongly associated with a longer survival time of patients as compared with that of a single gene.CONCLUSION： Expression of TS and TP mRNA is a useful predictive parameter for the survival of postoperative gastric cancer patients after 5-fluorouracilbased adjuvant chemotherapy.

Mechanochemical Coupling of Kinesin Studied with a Neck-Linker Swing Model

A neck-linker swing model has been proposed in this work to investigate the mechanochemical coupling of kinesin. The difference between force-velocity curves given by force clamp and fixed trap respectively has been satisfactorily interpreted by this model. The study implies that ADP releasing and ATP hydrolysis are much less forcedependent in force clamp experiments than that in fixed trap experiments in the regime of moderate loading force, which might be a consequence of the delayed response of servo system in force clamp experiments.

Coronatine Induces an Accumulation of Anthocyanin and Starch in Purple-fleshed Sweetpotato(Ipomoea batatas Lam.)

[Objective] The objective of this research was to examine the effects of COR on anthocyanin and starch content in storage roots of two PFS genotypes, and to explore the relationships between anthocyanin synthesis and starch accumula- tion. [Method] A field experiment was carried out to determine the changes in yielc components, yield, contents of anthocyanin and starch, activities of phenylalanine ammonia-lyase （PAL） and adenosine 5-diphosphate glucose pyrophosphorylase （AG- Pase） in two genotypes of PFS （Ipomoea batatas L., var. ＇Ayamurasaki＇ and ＇Jishu18＇）. [Result] The application of COR significantly increased starch and antho- cyanin content in storage roots of Jishu18 across developmental stages by inducing the activities of PAL and AGPase, and finally enhanced yield by promoting fresh weight of storage roots. Ayamurasaki was insensitive to treatment with COR al- though its PAL activity temporally increased. The starch and anthocyanin content of Aya, and the anthocyanin content of Jishu18 increased progressively across devel- opmental stages with or without COR application, but the starch content of Jishu18 increased initially, then decreased before increasing again without application of COR. Treatment with COR reduced downward trend of starch accumulation in Jishu18. Thus, the effect of COR on accumulation of anthocyanin and starch in storage roots of PFS differs according to genotypes. [Conclusion] The application of 0.05 μmol/L COR may increase starch and anthocyanin content in PFS genotypes with lower starch and anthocyanin content in storage roots.

Effect of electroacupuncture pretreatment on adenine nucleotides in myocardial tissues of rats with myocardial ischemia-reperfusion injury detected by high performance liquid chromatography(HPLC)

Objective:To observe the effect of electroacupuncture(EA)pretreatment on adenine nucleotides in the myocardial tissues of the myocardial ischemia-reperfusion injury(MIRI)rats,and to explore the mechanism of EA pretreatment on myocardial prevention and protection in MIRI rats.Methods:Forty SPF male Sprague-Dawley(SD)rats were randomly divided into 5 groups:a blank group,a sham operation group,a model group,an EA at Neiguan(PC 6)group and an EA at Hegu(LI 4)group,with 8 rats in each group.Rats in the blank group only received binding to the rat plate,30 min/time,once a day for 7 d;on the 7th day,rats in the sham operation group were subjected to threading for 40 min at the left anterior descending coronary artery without ligation,and then the rats were allowed to stand for 60 min before collection of the specimens;on the 7th day,rats in the model group were subjected to threading at the left anterior descending coronary artery with ligation,for 40 min before the blood flow was restored,and then the rats were allowed to stand for 60 min before collection of the specimens;on the 7th day of pretreatment with EA at Neiguan(PC 6)or Hegu(LI 4)for 30 min per day(once a day for 7 d),rats in the EA at Neiguan(PC 6)group and EA at Hegu(LI 4)group were subjected to modeling and sample collection same as in the model group.The left ventricular myocardium of the lower left anterior descending coronary artery was collected from rats in all 5 groups.Hematoxylin-eosin(HE)staining and transmission electron microscope(TEM)were used to observe the changes in myocardial pathological morphology.The change in the adenine nucleotide level of myocardial tissue was measured by high performance liquid chromatography(HPLC).Results:The HE staining and ultrastructure showed that the myocardial injury was severer in the model group compared with the sham operation group.Compared with the model group,the myocardial injury in the EA at Neiguan(PC 6)and the EA at Hegu(LI 4)groups was mild or hardly any.The adenine nucleotide levels in the sham operation group and the model group were all decreased compared with the blank group(all P<0.05);compared with the sham operation group,the adenine nucleotide level of the model group was also decreased,but the difference was not statistically significant(P>0.05);compared with the model group,the adenine nucleotide level in the EA at Neiguan(PC 6)group was increased(P<0.05),and the adenine nucleotide level in the EA at Hegu(LI 4)group was significantly increased(P<0.01).The adenine nucleotide level in the EA at Hegu(LI 4)group was higher than that in the EA at Neiguan(PC 6)group,but the difference was not statistically significant(P>0.05).Compared with the EA at Neiguan(PC 6)group,the levels of adenosine triphosphate(ATP),adenosine diphosphate(ADP)and adenosine monophosphate(AMP)in the EA at Hegu(LI 4)group were significantly increased(all P<0.01).Conclusion:Both EA at Neiguan(PC 6)and Hegu(LI 4)can alleviate the pathological damage to myocardium in MIRI rats,and increase the adenine nucleotide level in myocardial tissues,and thus protect MIRI rats.EA at Hegu(LI 4)has a better protective effect than Neiguan(PC 6).

RNA interference with DNA polymerase and synthesis

RNA can catalyze and participate in many chemical and biochemical reactions. Non-coding RNAs （ncRNA） can regulate cellular transcription and translation reactions. We have demonstrated biochemically that RNA can also interfere with DNA polymerization via transforming DNA polymerase into deoxyribonucleoside triphosphate diphosphatase （dNTP-DPase）. RNA, even with six nucleotides, can transform DNA polymerase into dNTP-DPase, and the dNTP-DPase activity causes the hydrolysis of dNTPs into dNMPs and pyrophosphate. Moreover, we have found that DNA polymerases from several families generally have similar RNA-dependent dNTP-DPase activity. We have also observed that in the presence of RNA, when the dNTP concentrations are relatively low, and that the dNTP-DPase activity can deplete dNTPs and interfere with DNA polymerization Thus, we have discovered for the first time that in the presence of RNA, DNA polymerase can behave as a diphosphatase and inhibit DNA synthesis when dNTP quantity is low. These in vitro observations might imply a plausible role of RNA in vivo, such as suppressing DNA synthesis during a resting phase （Go） of the cell cycle, when RNA quantity is high and dNTP quantity is low.

Effects of Dan Wei Powder (胆胃散) Tea Bag on Aggregation of Blood Platelet in vivo and in vitro

Objective: To observe effects of Dan Wei Powder (胆胃散 Powder for treating the gall bladder and stomach) Tea Bag (DWSTB) on the aggregation rate of blood platelet in vivo and in vitro. Methods: Increase of the platelet aggregation rate in the rat in vivo was induced by carrageenin, and increase of the rabbit platelet aggregation rate in vitro was induced by adenosine diphosphate (ADP) and collagen, respectively. The effects of DWSTB on the platelet aggregation rate were investigated in vivo and in vitro, respectively. Results: The maximum in vivo platelet aggregation rate in the rat was significantly decreased after administration of 2.0 and 4.0 g·kg-1 DWSTB (P<0.05.P<0.01). The maximum rabbit platelet aggregation rate induced by ADP and collagen in vitro were suppressed significantly by 2.0-16.0 mg·mL-1 and 2.0-8.0 mg·mL-1 DWSTB, respectively (P<0.05.P<0.01). And the effect of DWSTB on platelet aggregation was raised with increase ofits dose. Conclusion: Dan Wei Powder Tea Bag can restrain the aggregation of platelet in vivo and in vitro.

Protective effect of dihydropteridine reductase against oxidative stress is abolished with A278C mutation

Objective: To evaluate the antioxidation of dihydrobiopterin reductase and to explore the effect of A278C mutation of the quinoid dihydropteridine reductase(QDPR) gene on its antioxidant activity. Methods: First, plasmids with different genes(wild and mutant QDPR) were constructed. After gene sequencing, they were transfected into human kidney cells(HEK293T). Then, the intracellular production of reactive oxygen species(ROS) and tetrahydrobiopterin(BH4) was detected after cells were harvested. Activations of nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4), glutathione peroxidase 3(GPX3), and superoxide dismutase 1(SOD1) were analyzed to observe the oxidative stress after transfection. The expression of the neuronal nitric oxide synthase(n NOS) gene was analyzed by semiquantitative reverse-transcription polymerase chain reaction(RT-PCR). We also detected the activation of transforming growth factor β1(TGF-β1) by enzyme-linked immunosorbent assay(ELISA) to observe the connection of TGF-β1 and oxidative stress. Results: The exogenous wild-type QDPR significantly decreased the expression of n NOS, NOX4, and TGF-β1 and induced the expression of SOD1 and GPX3, but the mutated QDPR lost this function and resulted in excessive ROS production. Our data also suggested that the influence on the level of BH4 had no significant difference between mutated and the wild-type QDPR transfection. Conclusions: Wild-type QDPR played an important role in protecting against oxidative stress, but mutant QDPR failed to have these beneficial effects.