SiO2粉尘对巨噬细胞溶酶体损伤与细胞超微结构形态变化的关系

用电镜细泡化学技术观察了SiO_2粉尘对肺泡巨噬细胞溶酶体酸性磷酸酶细胞内分布的影响与细胞超微结构形态变化的关系。结果提示,较高SiO_2剂量所致的巨噬细胞损伤,并非完全是SiO_2粉尘与次级溶酶体膜直接相互作用的结果。     

硅胶催化下高效合成Naftopidil及其光学异构体

目的以硅胶作为催化剂,高效合成Naftopidil(Naf)及其光学异构体。方法在室温氮气保护和无溶剂条件下,使用60～100目硅胶催化萘氧基缩水甘油醚与邻甲氧基苯基哌嗪进行反应,得到Naf及其光学异构体。通过筛选催化剂的用量及循环使用次数优化反应。结果用20%的硅胶催化得到Naf,最佳收率为87%;硅胶循环5次,催化活性未见明显降低;对光学异构体的Naf的最佳收率为77%,ee值最高达98.2%。结论所用方法反应条件温和、收率高、产物与催化剂容易分离、催化剂可循环使用、活性未见明显降低,基本符合绿色化学反应的要求,具有良好的工业应用前景。     

纳米级和微米级二氧化硅粉尘对大鼠肺损伤的研究

目的：比较不同浓度纳米级与微米级二氧化硅粉尘对大鼠肺组织的损伤程度。方法：56只雄性W istar大鼠随机分为纳米级二氧化硅10.00 mg/100 g、15.00 mg/100 g、20.00 mg/100 g组,微米级二氧化硅10.00mg/100 g、15.00 mg/100 g、20.00 mg/100 g组和对照组;气管滴注二氧化硅粉尘10周后处死大鼠,观察肺组织损伤的程度。结果：纳米级、微米级二氧化硅组大鼠肺脏器系数均高于对照组,经检验差异有统计学意义（P〈0.05）,同剂量肺脏器系数比较纳米级大于微米级,差异有统计学意义（P〈0.05）;肺组织切片显示纳米级二氧化硅组肺泡排列紊乱、肺泡间隔增宽,其间有大量炎细胞浸润;微米级二氧化硅组肺组织有典型矽肺表现,肺大量纤维化、纤维细胞大量增生,可见明显矽结节。结论：微米级及纳米级二氧化硅对肺组织都有明显的损伤,损伤表现和程度不同。     

Effect of different surface treatments on In-Ceram Alumina roughness. An AFM study

Objectives

The aim of this study was to evaluate the influence of different treatments on the surface roughness of In-Ceram Alumina (VITA, Säckingen, Germany).

Methods

The ceramic blocks were polished (4000 grit) and sandblasted (SB) with airborne particle abrasion Al₂O₃; 110 μm particle size; 2.8 bar; 20 s. The following treatments were performed: (1) no treatment; (2) Rocatec System (RC): after SB treatment, sandblasting with silica powder; 30 μm particle size; 2.8 bar; 20 s. (3) Neodymium:yttrium–aluminium–garnet (Nd:YAG) laser (ND) application of graphite powder (stain) on the ceramic surface and Nd:YAG laser irradiation (distance: 1 mm, 100 mJ, 20 Hz, 2 W, and 141.54 J/cm²). (4) Nd:YAG laser plus Rocatec System: after ND treatments, RC was applied. Digital images (20 μm × 20 μm) from the surfaces were obtained by means of an AFM microscope in taping mode (Nanoscope IIIa, Digital Instruments). Roughness was measured in 10 μm × 10 μm boxes. Roughness (R_a) data (nm) were analyzed by one-way ANOVA (p < 0.05).

Results

No differences in ceramic surfaces roughness occurred after any of the tested treatments (p = 0.54).

Conclusions

High-alumina ceramic surface roughness was not increased with any of the tested treatments.     

Dispersive liquid-liquid microextraction,an effective tool for the determination of synthetic cannabinoids in oral fluid by liquid chromatography–tandem mass spectrometry

In the present work, dispersive liquid-liquid microextraction (DLLME) was used to extract six synthetic cannabinoids (JWH-018, JWH-019, JWH-073, JWH-200, or WIN 55,225, JWH-250, and AM-694) from oral fluids. A rapid baseline separation of the analytes was achieved on a bidentate octadecyl silica hydride phase (Cogent Bidentate C₁₈; 4.6 mm × 250 mm, 4 μm) maintained at 37 °C, by eluting in isocratic conditions (water:acetonitrile (25:75, V/V)). Detection was performed using positive electrospray ionization–tandem mass spectrometry. The parameters affecting DLLME (pH and ionic strength of the aqueous phase, type and volume of the extractant and dispersive solvent, vortex and centrifugation time) were optimized for maximizing yields. In particular, using 0.5 mL of oral fluid, acetonitrile (1 mL), was identified as the best option, both as a solvent to precipitate proteins and as a dispersing solvent in the DLLME procedure. To select an extraction solvent, a low transition temperature mixture (LTTM; composed of sesamol and chlorine chloride with a molar ratio of 1:3) and dichloromethane were compared; the latter (100 μL) was proved to be a better extractant, with recoveries ranging from 73% to 101 % by vortexing for 2 min. The method was validated according to the guidelines of Food and Drug Administration bioanalytical methods: intra-day and inter-day precisions ranged between 4 % and 18 % depending on the spike level and analyte; limits of detection spanned from 2 to 18 ng/mL; matrix-matched calibration curves were characterized by determination coefficients greater than 0.9914. Finally, the extraction procedure was compared with previous methods and with innovative techniques, presenting superior reliability, rapidity, simplicity, inexpensiveness, and efficiency.     

Lymphocyte activation in silica-exposed workers

Exposure to silica dust has been examined as a possible risk factor for autoimmune diseases, including systemic sclerosis, rheumatoid arthritis, systemic lupus erythematosus and ANCA-associated vasculitis. However, the underlying cellular and molecular mechanisms resulting in the increased prevalence of autoimmunity remain elusive. To clarify these mechanisms, we studied various markers of immune activation in individuals occupationally exposed to silica dust, i.e., serum levels of soluble IL-2 receptor (sIL-2R), levels of IL-2, other pro- and anti-inflammatory cytokines and lymphoproliferation. Our results demonstrate that silica-exposed individuals present important alterations in their immune response when compared to controls, as shown by increased serum sIL-2R levels, decreased production of IL-2 and increased levels of the pro-inflammatory (IFN-γ, IL-1α, TNF-α, IL-6) as well as anti-inflammatory (IL-10 and TGF-β) cytokines. Furthermore, silica-exposed individuals presented enhanced lymphoproliferative responses. Our findings provide evidence that the maintenance of immune homeostasis may be disturbed in silica-exposed individuals, possibly resulting in autoimmune disorders.     

二氧化硅粉尘作业工人肾功能损害的调查研究

对１５３名二氧化硅粉尘作业工人（接尘组）和８４名年龄相当但不接尘及其它毒物者（对照组）肾功能进行调查。结果发现接尘工人尿ＮＡＧ活性及尿α１－ＭＧ、β２－ＭＧ、Ａｌｂ含量较对照组显著升高，且随接尘工龄延长而明显升高，呈剂量－反应关系。若以超过对照组９５％单侧上限值为阳性标准，则尿α１－ＭＧ、β２－ＭＧ、Ａｌｂ、ＮＡＧ阳性率增高有显著意义，且尿酶与尿蛋白各指标之间呈正相关关系。表明长期接触含游离二氧化     

离子交换和硅胶柱色谱在化纤油剂剖析中的应用

本文介绍用离子交换法分离涤纶短纤维油剂、涤纶高速纺油剂、涤纶帘子线油剂、锦纶帘子线油剂、丙纶纤维油剂的、离子性和非离性成分,用15—20g青岛硅胶(200—300目)色层分离1500—2000mg油剂的非离子性成分;改进了醇溶液中环乙烷加成物的鉴定方法。     

实验大鼠矽肺纤维化扫描电镜观察

本文采用非暴露式气管内注入法，对大鼠一次染石英尘５０ｍｇ，在染法后１５、４５、９０、１８０和２７０天分批取样进行动态扫描电镜观察。结果表明，在实验早期肺泡腔内巨噬细胞聚集、成簇，Ⅱ型肺泡上皮细胞增生，部分转变为Ⅰ型上皮细胞、在肺泡间隔和肺泡壁上可见成纤维细胞，并分泌直径约０．０３μｍ的纤维，随着染尘时间延长，肺泡结构破坏，纤维增生相互交织呈网状和束状，导致肺间质和实质纤维化。