Comparative toxicity of silicon dioxide,silver and iron oxide nanoparticles after repeated oral administration to rats

Although silicon dioxide (SiO₂), silver (Ag) and iron oxide (Fe₂O₃) nanoparticles are widely used in diverse applications from food to biomedicine, in vivo toxicities of these nanoparticles exposed via the oral route remain highly controversial. To examine the systemic toxicity of these nanoparticles, well‐dispersed nanoparticles were orally administered to Sprague–Dawley rats daily over a 13‐week period. Based on the results of an acute toxicity and a 14‐day repeated toxicity study, 975.9, 1030.5 and 1000 mg kg^–1 were selected as the highest dose of the SiO₂, Ag and Fe₂O₃ nanoparticles, respectively, for the 13‐week repeated oral toxicity study. The SiO₂ and Fe₂O₃ nanoparticles did not induce dose‐related changes in a number of parameters associated with the systemic toxicity up to 975.9 and 1000 mg kg^–1, respectively, whereas the Ag nanoparticles resulted in increases in serum alkaline phosphatase and calcium as well as lymphocyte infiltration in liver and kidney, raising the possibility of liver and kidney toxicity induced by the Ag nanoparticles. Compared with the SiO₂ and Fe₂O₃ nanoparticles showing no systemic distribution in all tissues tested, the Ag concentration in sampled blood and organs in the Ag nanoparticle‐treated group significantly increased with a positive and/or dose‐related trend, meaning that the systemic toxicity of the Ag nanoparticles, including liver and kidney toxicity, might be explained by extensive systemic distribution of Ag originating from the Ag nanoparticles. Our current results suggest that further study is required to identify that Ag detected outside the gastrointestinal tract were indeed a nanoparticle form or ionized form. Copyright © 2015 John Wiley & Sons, Ltd.     

LC-MS determination and bioavailability study of imidapril hydrochloride after the oral administration of imidapril tablets in human volunteers

The purpose of the present study was to develop a standard protocol for imidapril hydrochloride bioequivalence testing. For this reason, a specific LC-MS method was developed and validated for the determination of imidapril in human plasma. A solid-phase extraction cartridge, Sep-pak C18, was used to extract imidapril and ramipril (an internal standard) from deproteinized plasma. The compounds were separated using a XTerra MS C18 column (3.5 microm, 2.1 x 150 mm) and acetonitrile-0.1% formic acid (67:33, v/v) adjusted to pH 2.4 by 2 mmol/L ammonium formic acid, as mobile phase at 0.3 mL/min. Imidapril was detected as m/z 406 at a retention time of ca. 2.3 min, and ramipril as m/z 417 at ca. 3.6 min. The described method showed acceptable specificity, linearity from 0.5 to 100 ng/mL, precision (expressed as a relative standard deviation of less than 15%), accuracy, and stability. The plasma concentration-versus-time curves of eight healthy male volunteers administered a single dose of imidapril (10 mg), gave an AUC12hr of imidapril of 121.48 +/- 35.81 ng mL(-1) h, and Cmax and Tmax values of 32.59 +/- 9.76 ng/mL and 1.75 +/- 0.27 h. The developed method should be useful for the determination of imidapril in plasma with sufficient sensitivity and specificity in bioequivalence study.     

6－甲氧基正丁苯酞在大鼠肝微粒体中的代谢研究

报道了用ＧＣ／ＭＳ方法及衍生化技术研究６甲氧基正丁苯酞（ＭＢＰ）在大鼠肝微粒体中的代谢转化结果。６甲氧基正丁苯酞在苯巴比妥（ＰＢ）诱导的大鼠肝微粒体中主要转化为３羟基、γ羟基取代物，６羟基正丁苯酞与一个环氧化代谢产物     

Efficacy of Seprafilm® graft with adhesiolysis in experimentally induced lid adhesion in rabbits

AIM:To evaluate the efficacy of Seprafilm^? transplantation following adhesiolysis for preventing postoperative readhesion and improving surgical outcomes.METHODS:Primary blepharoplasty was carried out on both eyelids of 18 albino rabbits. After 2 weeks, a new skin incision was made, and adhesiolysis was performed on both eyelids. The rabbits were categorized into two groups, one with adhesiolysis alone in the left eyelid (control group), and the other with adhesiolysis with a Seprafilm^? graft in the right eyelid (Seprafilm^? group). The degrees of inflammation and fibrosis were examined with hematoxylin-eosin (HE) and Masson’s trichrome stains. Expression of α-smooth muscle actin (α-SMA) was also immunohistochemically examined.RESULTS:Eyelid examination immediately after the operation revealed mild swelling and hemorrhage in both groups, but these symptoms resolved after 1 week-2 weeks, and eyelid shape had recovered completely in both groups. Microscopic assessments demonstrated that the Seprafilm^? group showed less inflammation and fibrosis than the control group. The Seprafilm^? group also exhibited fewer α-SMA-positive cells than the control group.CONCLUSION:Based on these findings, we conclude that Seprafilm^? graft with adhesiolysis is an effective method for preventing postoperative readhesions after eyelid surgery.     

临床感染病原菌菌种分布及其耐药性分析

目的了解笔者所在医院2008年度临床感染病原菌的菌种分布及其耐药现状。方法用VITEK微生物自动鉴定仪鉴定菌种,纸片扩散法检测临床分离菌对各种抗菌药物的敏感性,判读标准参照当年的CLSI M100文件。结果临床分离的1900株病原菌中革兰阴性杆菌、革兰阳性球菌和真菌所占比例分别为68.42%、18.16%和12.32%。分离率最高的五种病原菌:铜绿假单胞菌、大肠埃希菌、肺炎克雷伯菌、鲍曼不动杆菌和白色假丝酵母菌,占所有分离病原菌的59.26%,排前20位的病原菌则占到近90%(89.63%)。革兰阴性杆菌仅对亚胺培南、头孢哌酮/舒巴坦、美洛培南、哌拉西林/他唑巴坦的平均耐药率低于30%,铜绿假单胞菌和鲍曼不动杆菌对亚胺培南、美洛培南的耐药率分别28.9%、32.9%和11.6%、24.7%,大肠埃希菌、肺炎克雷伯菌和奇异变形杆菌的ESBL阳性率分别是52.8%、37.2%和34.6%,金黄色葡萄球和凝固酶阴性葡萄球菌中耐甲氧西林株各占44.0%和60.0%,未检出万古霉素中介或耐药的葡萄球菌,检出万古霉素耐药的粪肠球菌和屎肠球菌各1株。念珠菌对氟康唑耐药率接近5%。结论临床感染病原菌构成变化不大,但真菌检出率逐年升高。非发酵菌耐药率最低的是头孢哌酮/舒巴坦,肠杆菌科耐药率最低的是亚胺培南,ESBL的阳性率逐年升高。加强病原菌及其耐药性检测和监测,对病原学诊断及指导合理选用抗生素具重要参考价值。     

羧乙基锗倍半氧化物对正常和异丙基肾上腺素损伤培养乳鼠心肌细胞的影响

羧乙基锗倍半氧化物(Ge—132)能促进培养乳鼠心肌细胞DNA和RNA的合成,提高超氧化物歧化酶(SOD)的活性,维持细胞膜结构的稳定。异丙基肾上腺素可使心肌细胞乳酸脱氢酶(LDH)释放增加,细胞搏动停止,超微结构显示肌膜和线粒体严重受损。Ge—132可显著减少异两基肾上腺素引起心肌细胞释放LDH,维持细胞的搏动功能和超微结构的完整。     

苦楝化学成份的研究

从苦楝(Melia azedarach L.)果中分得苦楝新醇(Ⅰ),苦楝醇(Ⅱ)、苦楝酮(Ⅲ)、苦楝二醇(Ⅳ)、香草醛(Ⅴ)和香草酸(Ⅵ)。根据波谱(IR,MS,~1HNMR,~(13)CNMR)分析和理化常数测定,确定了它们的结构。其中苦楝新醇(Ⅰ)为新化合物,对菜青小虫有一定的拒食活性。