离子色谱法测定维生素B1注射液中的EDTA及硝酸根离子

目的： 建立测定维生素B₁注射液中EDTA及硝酸根离子含量的离子色谱法。 方法： 采用IonPac AS 11-HC色谱柱（4.0 mm ×250 mm）,IonPac AS 11-HC guard保护柱（4.0 mm×50 mm）和ASRS 300抑制器（4 mm）,淋洗液为12 mmol·L^-1氢氧化钠,流速1.0 mL·min^-1,抑制电流60 mA,电导检测器温度35℃,柱温30℃,进样体积25 μL。 结果： EDTA和硝酸根离子检出限分别为0.29,0.01 mg·L^-1,EDTA在1.19～23.8 mg·L^-1,线性关系良好（r=0.999 7）,回收率为98.2%～100.6%;硝酸根离子在1.0～10.0 mg·L^-1线性关系良好（r=0.999 6）,回收率为97.9%～99.5%。 结论： 该实验方法选择性高,灵敏度好,测定结果准确,并且简便,快速,可用于注射液中ETDA及硝酸根离子的测定研究和质量控制。     

盐酸特比萘芬硝酸益康唑乳膏的皮肤毒性试验研究

目的:考察盐酸特比萘芬硝酸益康唑乳膏(特益乳膏)的皮肤毒性.方法:以不同剂量特益乳膏作用于SD大鼠背部正常和破损皮肤,进行急性毒性试验;用豚鼠进行皮肤过敏性试验,用新西兰白兔背部正常和破损皮肤进行皮肤刺激性试验.结果:特益乳膏对受试动物皮肤均未产生急性毒性、过敏性和刺激性.结论:特益乳膏的皮肤毒性较低,外用安全.     

Investigating oxidative stress and inflammatory responses elicited by silver nanoparticles using high-throughput reporter genes in HepG2 cells: Effect of size,surface coating,and intracellular uptake

Silver nanoparticles (Ag NP) have been shown to generate reactive oxygen species; however, the association between physicochemical characteristics of nanoparticles and cellular stress responses elicited by exposure has not been elucidated. Here, we examined three key stress-responsive pathways activated by Nrf-2/ARE, NFκB, and AP1 during exposure to Ag NP of two distinct sizes (10 and 75 nm) and coatings (citrate and polyvinylpyrrolidone), as well as silver nitrate (AgNO₃), and CeO₂ nanoparticles. The in vitro assays assessed the cellular response in a battery of stable luciferase-reporter HepG2 cell lines. We further assessed the impact of Ag NP and AgNO₃ exposure on cellular redox status by measuring glutathione depletion. Lastly, we determined intracellular Ag concentration by inductively coupled plasma mass spectroscopy (ICP-MS) and re-analyzed reporter-gene data using these values to estimate the relative potencies of the Ag NPs and AgNO₃. Our results show activation of all three stress response pathways, with Nrf-2/ARE displaying the strongest response elicited by each Ag NP and AgNO₃ evaluated here. The smaller (10-nm) Ag NPs were more potent than the larger (75-nm) Ag NPs in each stress-response pathway, and citrate-coated Ag NPs had higher intracellular silver concentrations compared with both PVP-coated Ag NP and AgNO₃. The cellular stress response profiles after Ag NP exposure were similar to that of AgNO₃, suggesting that the oxidative stress and inflammatory effects of Ag NP are likely due to the cytotoxicity of silver ions.     

Organic nitrate-induced oxidant stress and cardiovascular therapy

First clinically introduced in the 19th century, organic nitrates are likely to remain the mainstay of nitrovasodilator-based therapy of angina pectoris, acute myocardial infarction and congestive heart failure well into the future. However, the utility and affordability of continuous cardiovascular disease management with organic nitrates has historically been compromised by the rapid development of nitrate tolerance, the requirement for nitrate-free periods and rebound phenomena. While recent landmark research has proposed a novel nitrate-induced oxidant stress mechanism of nitrate tolerance that may be readily modifiable in the clinic, the implications of these findings for the future of nitric oxide (NO) pharmacotherapy in cardiovascular disease have yet to be fully explored. In particular, organic nitrate-induced oxidant stress may not only have a pivotal role in attenuating organic nitrate bioconversion and vascular NO bioavailability vis-à-vis nitrate tolerance development, but may also potentially aggravate both endothelial dysfunction and insulin resistance in cardiovascular disease and Type 2 diabetes. Such deleterious actions may now help account for the disappointing neutral effects of organic nitrate therapy on mortality in coronary care documented in large-scale clinical trials.     

利用全胚胎和微团培养模型评价硝酸镧的发育毒性

目的： 利用大鼠植入后全胚胎培养模型和微团培养模型评价硝酸镧潜在的胚胎早期和中、晚期发育毒性。方法： 将大鼠胚胎随机分为5组后培养于含不同剂量硝酸镧（0、0.12、0.23、0.46及1 mmol/L）的即刻离心血清中，48 h后测量胚胎卵黄囊直径（YSD）、顶臀长（CRL）和头长（HL），计数体节，并根据Brown's评分法对胚胎进行总形态学评分（TMS）。同时，对BALB/c 3T3细胞进行细胞毒性测试。根据欧洲替代方法验证中心（ECVAM）的预测模型对硝酸镧的胚胎早期发育毒性进行评价。分离大鼠胚胎肢芽细胞，制成单细胞悬液，进行微团培养。分别用0.03、0.06、0.13、0.25、0.5、1、2及3 mmol/L硝酸镧进行染毒，利用中性红活细胞摄取染色法测定50%细胞增殖受抑制时的浓度（IC₅₀）以反映细胞增殖情况，利用阿利新蓝染色法测定50%细胞分化受抑制时的浓度（ID₅₀）以反映细胞分化情况。根据ECVAM预测模型对硝酸镧胚胎中晚期发育毒性进行评价。结果： 硝酸镧对胚胎生长的无可见有害作用水平（NOAEL）为0.12 mmol/L，0.46 mmol/L硝酸镧可明显降低胚胎YSD、CRL和HL（P < 0.05），对胚胎生长有明显的抑制效应。0.46 mmol/L硝酸镧可诱导胚胎产生发育畸形，减少胚胎体节形成数目（P < 0.05）。硝酸镧对肢芽细胞增殖活性的NOAEL为1 mmol/L，对肢芽细胞分化为软骨细胞的NOAEL为0.25 mmol/L，其IC₅₀和ID₅₀分别为1.57 mmol/L（510.25 μg/mL）和0.99 mmol/L（321.75 μg/mL）。结论： 经全胚胎培养预测模型评价硝酸镧为弱胚胎发育毒性化学物；经微团培养模型评价硝酸镧为无胚胎发育毒性化学物。     

Polyenylphosphatidylcholine pretreatment protects rat liver from ischemia/reperfusion injury

Background

Hepatic injury induced by ischemia/reperfusion following surgery, transplantation, or circulatory shock combined with resuscitation is a major clinical problem. Polyenylphosphatidylcholine (PPC) has strong antioxidant, cytoprotective and anti-inflammatory effects.

Aim

In this study, the influence of PPC pretreatment on ischemia-reperfusion (I/R) injury of the liver was examined in rats.

Methods

The animals were divided into three groups: control (n = 10), I/R (n = 15) and I/R + PPC (n = 15). PPC was given 100 mg/day for 7 days before experiment. Several parameters of hepatic damage, oxidative stress, neutrophil infiltration and nuclear factor kappa beta (NF-κB) expression were measured as well as microscopic examination.

Results

We observed that a significant reduction in AST and ALT values in the PPC treated group when compared with the ischemic group. The increases in hepatic total NO₂ + NO₃ and MDA, and decreases in SOD and GSH levels after reperfusion were partially, but significantly, inhibited by PPC pretreatment. I/R induced increase in hepatic myeloperoxidase content and NF-κB expression were also lowered by PPC pretreatment. Animals pretreated with PPC presented minimal hemorrhage and reduced signs of liver injury.

Conclusion

PPC pretretament provided significant protection againts I/R injury to the liver. This treatment could be therapeutic in liver transplantation and other conditions associated with I/R injury.     

Evaluation of nitrate reductase assay for direct detection of drug resistance in Mycobacterium tuberculosis: rapid and inexpensive method for low-resource settings

The aim of this study was to evaluate a nitrate reductase assay (NRA) for the direct detection of multidrug resistance (MDR) in Mycobacterium tuberculosis from 100 smear-positive sputum samples. The NRA results were compared with the reference proportion method for 100 sputum specimens for which comparable results were available. NRA results were obtained at day 7 for 61 specimens, results for 26 specimens were obtained at day 10, and the results for 13 specimens were obtained at day 14. Thus, 87% of NRA results were obtained in 10 days. NRA is a rapid, accurate, and cost-effective method for the detection of MDR in M. tuberculosis isolates as compared to the proportion method, which is time consuming. Therefore, NRA constitutes a useful tool for detection of tuberculosis drug resistance in low-resource countries with limited laboratory facilities due to its low-cost, ease of performance and lack of requirement of sophisticated equipment.     

星点设计-效应面法优化硝酸布康唑缓释乳膏的制备

目的 采用星点设计-效应面法对硝酸布康唑缓释乳膏的处方进行优化。方法 以液体石蜡用量(X₁)、乳化剂用量(X₂)、助乳化剂占乳化剂比例(X₃)为考察因素,以24,48,72 h的累积释放度为考察指标,分别用多元线性模型、二次多项式模型描述考察指标和3个考察因素之间的数学关系,根据模型绘制效应面图和等高线图,通过重叠等高线图确定优化处方,最后进行验证。结果 二次多项式模型比多元线性模型置信度高;根据二次多项式模型,发现 3 个考察因素和 3个考察指标之间存在可信的定量关系;优化处方各设定指标的预测值和实际值非常接近。结论 星点设计-效应面法可用于硝酸布康唑缓释乳膏的处方优化,所建模型具有良好的预测能力。     

HPLC法同时测定特益乳膏中盐酸特比萘芬和硝酸益康唑的含量

目的：建立同时测定特益乳膏中盐酸特比萘芬和硝酸益康唑含量的HPLC方法。方法：采用HypersilODS,色谱柱（250mm×4．6mm,5μm）,流动相为甲醇一磷酸盐缓冲液（取磷酸二氢钾与磷酸氢二钾各2．5g,加水溶解并稀释至1000na）（85：15）,流速：1．0ml·min^-1,柱温：25℃;检测波长为232nln。结果：盐酸特比萘芬在80．0～640．0μg·ml^-1。范围内呈良好的线性关系（r=0．9993）,平均回收率分别为100．69％、100．97％、99．06％;硝酸益康唑在20．0～200．0μg·ml^-1。范围内呈良好的线性关系（r=0．9991）,平均回收率分别为101．41％、99．68％、98．56％。结论：建立的方法准确、可靠,可用于特益乳膏的质量控制。     

RFIC法快速检查纯化水中4种阴离子

目的:建立免化学试剂离子色谱法(RFIC)快速检查纯化水中氯化物、硫酸盐、硝酸盐、亚硝酸盐4种阴离子。方法:采用ICS-3000型离子色谱仪,AS18色谱柱,以23 mmol.L-1氢氧化钾溶液为淋洗液,流速为1.0 mL.min-1。结果:4种阴离子的线性范围分别为:Cl-:0.05~5.0 mg.L-1;SO42-:0.1~10.0 mg.L-1;NO2-:0.01~1.0 mg.L-1;NO3-:0.02~2.0 mg.L-1;r值均大于0.9990。检出限分别为Cl-:0.005 mg.L-1;SO42-:0.01 mg.L-1;NO2-:0.005 mg.L-1;NO3-:0.01 mg.L-1。在0.05mg.L-1浓度下进行精密度试验,RSD均小于3%(n=6)。加样回收率为97.4%~104.3%。结论:该方法操作简便、快速、准确,免化学试剂,可以代替药典法来检查纯化水中的4种阴离子。