克银合剂治疗血热型白疕疗效及对肿瘤坏死因子-α的影响

目的 研究克银合剂治疗血热型白疕(寻常型银屑病)疗效及对肿瘤坏死因子-α(TNF-α)的影响.方法 选取30例寻常型银屑病血热型患者作为研究对象,进行克银合剂治疗,另选取同期接受健康体检的健康人30例作为对照组,研究克银合剂对TNF-α的影响.结果 治疗前TNF-α水平显著高于健康对照组,进行克银合剂治疗后患者症状、体征评分均显著低于治疗前,各项指标水平已经接近对照组.结论 克银合剂能改善寻常型银屑病血热型患者的临床症状,对TNF-α异常也有一定的改善作用.     

微卫星多态性检测时银染色和同位素技术比较

为了比较银染色技术与传统的同位素技术在微卫星多态性检测中的优缺点，对ｌｌ８例正常男性基因组ＤＮＡ，用Ｙ染色体特异性微卫星作聚合酶链式反应，经聚丙烯醚胺序列分析后，分别作银染色和同位素检测。结果表明前者重复性好，结果满意，具有经济、对操作者和环境无害、一天即可出结果等优点。对银染色的不足之处进行了探讨。     

愈合灵(磺胺嘧啶锌)的毒理研究

愈合灵的毒性实验证明:小白鼠腹腔注射 LD_(50)为529±86.1mg/kg。长期(三个月)给太白鼠腹腔注射,则具有磺胺嘧啶本身所致的肾脏损害,但这种损害为可逆性病变,如能及时停药则可逐渐恢复。皮下注射时毒性很低。     

纳米银凝胶经阴道给药后在家兔体内的分布特征

目的 给予家兔阴道内纳米银凝胶后,研究银在家兔体内的分布情况.方法 单剂量和多剂量经♀家兔阴道给予纳米银凝胶200 mg∶ kg-1后,于不同时间点处死家兔并剖取主要组织器官,用ICP-MS法测定给药前、后家兔各器官中银的含量.结果 与0h组比较,单剂量给药后,阴道、子宫和肝脏中银的含量明显增加,其余组织中未见明显分布,给药72 h后各组织中银的含量均恢复至本底水平;多剂量给药后,末次给药2 ～24 h内阴道、子宫、肝脏、脾、肾、大肠和小肠中有银的分布,心、脑、肺和胃未见明显分布,末次给药72 h后各组织中银的含量均恢复至本底水平.结论 单剂量和多剂量经家兔阴道给予纳米银凝胶后,给药2 ～24 h内银在组织中有分布,给药72 h后各组织中均未见明显银蓄积.     

Antibacterial‐nanocomposite bone filler based on silver nanoparticles and polysaccharides

Injectable bone fillers represent an attractive strategy for the treatment of bone defects. These injectable materials should be biocompatible, capable of supporting cell growth and possibly able to exert antibacterial effects. In this work, nanocomposite microbeads based on alginate, chitlac, hydroxyapatite and silver nanoparticles were prepared and characterized. The dried microbeads displayed a rapid swelling in contact with simulated body fluid and maintained their integrity for more than 30 days. The evaluation of silver leakage from the microbeads showed that the antibacterial metal is slowly released in saline solution, with less than 6% of silver released after 1 week. Antibacterial tests proved that the microbeads displayed bactericidal effects toward Staphylococcus aureus, Pseudomonas aeruginosa and Staphylococcus epidermidis, and were also able to damage pre‐formed bacterial biofilms. On the other hand, the microbeads did not exert any cytotoxic effect towards osteoblast‐like cells. After characterization of the microbeads bioactivity, a possible means to embed them in a fluid medium was explored in order to obtain an injectable paste. Upon suspension of the particles in alginate solution or alginate/hyaluronic acid mixtures, a homogenous and time‐stable paste was obtained. Mechanical tests enabled to quantify the extrusion forces from surgical syringes, pointing out the proper injectability of the material. This novel antibacterial bone filler appears as a promising material for the treatment of bone defects, in particular when possible infections could compromise the bone‐healing process. Copyright © 2016 John Wiley & Sons, Ltd.     

Flow cytometry evaluation of in vitro cellular necrosis and apoptosis induced by silver nanoparticles

Particles possess unique properties in the nanoscale, e.g., enhanced catalytic activity, high surface area, and light emission/absorption properties, that might result in interference with colorimetric in vitro cytotoxicity assays such as MTT, XTT or MTS. Alternatively, assays that do not use spectrophotometric detection, such as trypan blue exclusion or flow cytometry (FC) based assays, are less likely to be influenced by nanoparticle interference. The aim of this study was to evaluate FC assays to assess the cytotoxicity of three different sizes (10, 100, or 200 nm) of silver nanoparticles (AgNPs) at different mass concentrations (1, 25, or 50 ug/ml) in L-929 fibroblast cells. After 4 h and 24 h exposure, cell necrosis and apoptosis were assessed using 7-AAD and Annexin V dyes, respectively, with FC. The data indicate that cell necrosis and apoptosis in AgNP-exposed fibroblasts depends on dose, exposure time, and AgNP size. The data indicate that AgNPs produced a dose- and time-dependent decrease in cell viability; however, 10 nm AgNPs were significantly more toxic than larger-sized particles. Thus, standard FC assays can be utilized to assess apoptosis and necrosis in response to nanomaterial exposure.     

Potential of biofluid components to modify silver nanoparticle toxicity

Establishing realistic exposure scenarios is critical for cytotoxic investigation of silver nanoparticles (AgNP) in the gastrointestinal tract. This study investigated the potential interaction with and effect of biofluid components, namely cholic acid, deoxycholic acid and ursodeoxycholic acid, on AgNP toxicity. Two cell lines corresponding to organs related to the biofluid components were employed. These were HepG‐2 a hepatocellular carcinoma derived from liver tissue and Hep2 an epithelial cell line. Physiochemical and cytotoxic screening was performed and the ability of biofluid components to modify AgNP cytotoxicity was explored. No alteration to the physiochemical characteristics of AgNP by biofluid components was demonstrated. However, biofluid component addition resulted in alteration of AgNP toxicity. Greater reactive oxygen species induction was noted in the presence of cholic acid and deoxycholic acid. Ursodeoxycholic acid demonstrated no modification of toxicity in HepG‐2 cells; however, significant modification was noted in Hep2 cells. It is concluded that biofluid components can modify AgNP toxicity but this is dependent on the biofluid component itself and the location where it acts. Copyright © 2015 John Wiley & Sons, Ltd.     

Compatibility of Different Histochemical Techniques for the Demonstration of ATPase for Muscle Fiber Typing: A Review

Abstract

Several recent studies suggest a diagnostic and a possible prognostic role for silver stained nucleolar organizer region (AgNOR) determination in the assessment of human neoplasia. Technical pitfalls, especially silver grain precipitate, may hamper accurate counting of AgNORs. We have identified pH as a main factor causing silver precipitation and overstaining. An improved silver staining method, which raises the pH to 3.0, optimizes visualization by eliminating silver precipitation and improving contrast between AgNORs and surrounding tissue components. (The J Histotechnol 14:187, 1991)     

Antibacterial activities of hexadecanoic acid methyl ester and green-synthesized silver nanoparticles against multidrug-resistant bacteria

Antibacterial drug resistance is considered one of the biggest threats to human health worldwide, and the overuse of antibiotics accelerates this problem. Multidrug-resistant (MDR) bacteria are becoming harder to treat as the antibiotics used to treat them become less effective. Therefore, it is necessary to evaluate novel methods to control MDR bacteria. In this study, 40 bacterial isolates were collected from diabetic patients. The sensitivity of 40 bacterial isolates to seven antibiotics was evaluated. Four bacterial isolates were resistant to all antibiotic groups. The MDR pathogenic bacteria were selected and identified morphologically and biochemically and confirmed by VITEK® 2 system as follows: Staphylococcus aureus W35, Pseudomonas aeruginosa D31, Klebsiella pneumoniae DF30, and K. pneumoniae B40. Identification of the most resistant P. aeruginosa D31 was confirmed by the sequencing of a 16S ribosomal RNA gene with an accession number (MW241596). The inhibitory activity of eight types of native grown plant extracts against MDR bacteria was studied. Clove alcoholic extract (CAE) showed the highest inhibitory activity against MDR bacteria. Gas chromatography–mass spectrometry analysis of partially purified CAE at 0.9 Rf detected by thin-layer chromatography showed an active compound named hexadecenoic acid methyl ester with the highest antimicrobial effect against clinical pathogenic bacteria. The formation of silver nanoparticles (AgNPs) by CAE was studied. Evaluation of AgNPs was investigated by X-ray diffraction, UV–Vis, and transmission electron microscopy. The antibacterial effect of AgNPs after 2, 4, and 6 days in light and dark conditions was evaluated. Finally, the AgNPs synthesized using CAE possess good inhibition activity against the tested pathogenic bacteria. As a result, the bactericidal components listed above were promising in reducing MDR bacteria and can be used for treatments of bacterial infection and in the development of safe products with a natural base.