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1.
Melita Kosanovic Mohammad Yousif Hasan Dhanasekhar Subramanian Abdulla Ali Falah Al Ahbabi Omar Ali Awn Al Kathiri Essa Mohammed Ali Abdulla Aleassa Abdu Adem 《Food and chemical toxicology》2007,45(11):2261-2266
We hypothesized that increased ambient concentrations of metals, as a consequence of escalating urbanization and industrialization of the Gulf region will respond in increased contamination of edible fish species. In this study, we report concentrations of chromium, manganese, cobalt, copper, zinc, arsenic, cadmium, mercury and lead in meat and liver of wild Red-spot emperor (Lethrinus lentjan) from three sampling points at the UAE coast. Analysis was performed by the ICP-MS/microwave digestion. Our study has shown that meat and liver metal content was significantly higher in areas with higher industrial activity, although metal values did not exceed permitted levels of fish for human consumption. 相似文献
2.
David G. Kern 《American journal of industrial medicine》1994,25(5):759-767
Lead poisoning in a precious metals refinery fire assayer and a routine OSHA inspection prompted an investigation of the index facility, a survey of the industry, and efforts to notify assayers of this previously unrecognized hazard. Air and blood samples were obtained at the index facility. Management personnel from all fire assay laboratories in Rhode Island and southern Massachusetts were interviewed. The industry's trade association, OSHA, NIOSH, trade unions, and the media were asked to assist in a nationwide notification effort. Assayers at the index facility had excessive exposures to lead due to an age-old, lead-based assaying method that remains the industry gold standard. Blood lead levels of the three assayers (mean 61.3 μ/dl, range 48–86 μg/dl) were considerably higher than those of 16 other refinery workers (mean 27.4 μg/dl, range 13–49 μg/dl). The industry survey revealed inadequate knowledge of both the lead hazard and the applicability of the OSHA lead standard. Notification efforts failed in large part due to economic obstacles. The notification of workers at high risk of lead exposure and the eradication of occupational lead poisoning will require greater attention to economic forces. © 1994 Wiley-Liss, Inc. 相似文献
3.
Soluble CD14 but not interleukin-6 is a new marker for clinical activity in atopic dermatitis 总被引:4,自引:0,他引:4
Summary Levels of soluble IL-2 receptors, IL-6, soluble CD23, soluble CD14 and ECP (eosinophilic cationic protein) were measured as markers of T-cell, B-cell, monocyte and eosinophilic leucocyte activation in 26 patients with atopic dermatitis (AD) on admission to (A) and at discharge from (D) the Department of Dermatology in Zurich. The serum levels of sIL-2R, IL-6, sCD23, sCD14 and ECP were significantly elevated in AD patients in comparison with the normal values of healthy donors. A significant decrease in sIL-2R (p=0.0093) and in sCD14 (p=0.0134) levels was demonstrated between A and D, correlating with the improvement in the skin intensity score (SIS). In addition, a significant correlation of the sCD14 levels and the SIS at A was demonstrated (p=0.0415). These results also incriminate monocytes in the pathogenesis of AD, indicating that, besides sIL-2R and ECP, SCD14 could also be a possible marker for the disease activity. 相似文献
4.
Tom Lindfors Carita Kvarnström Ari Ivaska 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,518(2):131-138
Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λexc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl2 solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI. 相似文献
5.
目的 探讨可溶性白细胞介素 2受体 (sIL 2R)和可溶性白细胞介素 6受体 (sIL 6R)在多发性硬化(MS)发病过程中的作用。方法 采用双体夹心ELISA法对 2 9例MS急性期患者及 2 0例炎性神经病患者、39例非炎性神经病患者、2 0例健康对照者脑脊液和血清中sIL 2R和sIL 6R的含量进行检测。结果 MS患者血清和脑脊液中sIL 2R、sIL 6R含量明显高于非炎性神经病组 (P <0 .0 5 )及健康对照组 (P <0 .0 1) ;MS组sIL 2R和血清sIL 6R含量与炎性神经病组比较 ,无显著性差异 ,但脑脊液中sIL 6R水平明显低于炎性神经病组 (P <0 .0 1)。结论 sIL 2R和sIL 6R在MS急性期患者体内明显升高 ,进一步证实了MS有关免疫学的发病机制 ,并为临床诊断MS提供了具有参考价值的实验室指标 相似文献
6.
GraVes眼病炎性活动期与静止期血清sICAM-1水平的研究 总被引:1,自引:1,他引:0
目的:研究可溶性细胞间粘附因子-1(sICAM-1)在Graves眼病(GO)炎性活动期与静止期的水平差异及其与各项甲状腺功能指标的关系。方法:将GO炎性活动期与静止期患者,Graves病(GD)无眼病患者及正常对照,分为A、B、C、D四组,抽取空腹静脉全血,测血清sICAM-1,各组间进行比较。并分析各组sICAM-1与FT3、FT4、TG、TM的相关关系。结果:①A、B、C组患者血清sICAM-1均明显高于正常对照组(P<0.05)。A组患者sICAM-1水平最高,与B组及C组患者相比有统计学差异(P<0.01);②前三组各组内sICAM-1与FT3、FT4成直线相关关系,与TG、TM成直线相关关系;③GO炎性活动期患者sICAM-1与GO评分成正相关。结论:血清sICAM-1水平可作为反映GO活动性评判的免疫指标,长期监测sICAM-1可预示GD进展为临床活动性眼病的可能性。 相似文献
7.
Alexander Mülsch Eberhard Bassenge Rudi Busse 《Naunyn-Schmiedeberg's archives of pharmacology》1989,340(6):767-770
Summary Release of nitric oxide (NO) from endothelial cells critically depends on a sustained increase in intracellular free calcium maintained by a transmembrane calcium influx into the cells. Therefore, we studied whether the free cytosolic calcium concentration directly affects the activity of the NO-forming enzyme(s) present in the cytosol from freshly harvested porcine aortic endothelial cells. NO was quantified by activation of a purified soluble guanylate cyclase coincubated with the cytosol. In the presence of 1 mM L-arginine, 0.1 mM NADPH and 0.1 mM EGTA, endothelial cytosol (0.2 mg of cytosolic protein per ml) stimulated the activity of guanylate cyclase 5.0 + 0.5-fold (from 31 + 9 to 153 + 15 nmol cyclic GMP formed per min per mg guanylate cyclase). Calcium chloride increased this stimulation further in a concentration-dependent fashion by up to 136 + 15% (with 2 M free calcium; EC50 0.3 M). The calcium-dependent and -independent activation of guanylate cyclase was enhanced by superoxide dismutase (0.3 M) and was inhibited by the stereospecifically acting inhibitor of L-arginine-dependent NO formation NG-nitro-L-arginine (1 mM) and by LY 83583 (1 M), a generator of superoxide anions. Our findings suggest a calcium-dependent and -independent synthesis of NO from L-arginine by native porcine aortic endothelial cells.
Send of fprint requests to A. Mülsch, at the above address 相似文献
8.
Contribution of redox-active iron and copper to oxidative damage in Alzheimer disease 总被引:1,自引:0,他引:1
Castellani RJ Honda K Zhu X Cash AD Nunomura A Perry G Smith MA 《Ageing research reviews》2004,3(3):319-326
Metal-catalyzed hydroxyl radicals are potent mediators of cellular injury, affecting every category of macromolecule, and are central to the oxidative injury hypothesis of Alzheimer disease (AD) pathogenesis. Studies on redox-competent copper and iron indicate that redox activity in AD resides exclusively within the neuronal cytosol and that chelation with deferoxamine, DTPA, or, more recently, iodochlorhydroxyquin, removes this activity. We have also found that while proteins that accumulate in AD possess metal-binding sites, metal-associated cellular redox activity is primarily dependent on metals associated with nucleic acid, specifically cytoplasmic RNA. These findings indicate aberrations in iron homeostasis that, we suspect, arise primarily from heme, since heme oxygenase-1, an enzyme that catalyzes the conversion of heme to iron and biliverdin, is increased in AD, and mitochondria, since mitochondria turnover, mitochondrial DNA, and cytochrome C oxidative activity are all increased in AD. These findings, as well as studies demonstrating a reduction in microtubule density in AD neurons, suggest that mitochondrial dysfunction, acting in concert with cytoskeletal pathology, serves to increase redox-active heavy metals and initiates a cascade of abnormal events culminating in AD pathology. 相似文献
9.
Low interleukin-2 receptor levels in serum of patients with insulin-dependent diabetes 总被引:1,自引:0,他引:1
R. Wagner E. Bonifacio P. J. Bingley S. Genovese D. Reinwein G. F. Bottazzo 《Journal of molecular medicine (Berlin, Germany)》1994,72(7):494-498
Interleukin-2 receptors are released in the circulation in response to antigenic or mytogenic stimulation of T-lymphocytes. Abnormal serum interleukin-2 receptor levels have been found in young children with type 1 diabetes and prediabetes. We measured interleukin-2 receptor levels in 17 patients with newly diagnosed type 1 diabetes, 21 patients with long-standing type 1 diabetes, 19 patients with long-standing type 2 diabetes, 19 islet-cell antibody positive nondiabetic polyendocrine patients, 12 islet-cell antibody-positive first-degree relatives of patients with type 1 diabetes and compared the results to age- and sex-matched normal controls. We found significantly lower interleukin-2 receptor levels in patients with newly diagnosed and long-standing type 1 diabetes compared to normal controls (87 ± 11 and 93 ± 11 vs. 142 ± 25 and 132 ± 40 U/ml, P < 0.001 and P < 0.01). There were no significant differences in interleukin-2 receptor levels between prediabetic groups and normal controls or patients with long-standing type 1 or type 2 diabetes. There was no correlation between glycosylated hemoglobin, blood glucose levels, and interleukin-2 receptor in the groups with long-standing type 1 or type 2 diabetes. We conclude that patients with type 1 diabetes have low interleukin-2 receptor serum levels. This phenomenon is acquired close to disease onset and is unlikely to be an early markers of type 1 diabetes.Abbreviations JDf
Juvenile Diabetes foundation
- ICA+
islet-cell antibody positive
- IDDM
insulin-dependent diabetes mellitus
- IL-2R®
interleukin-2 receptors
- NIDDM
non-insulin-dependent diabetes mellitus
Correspondence to: R. Wagner 相似文献
10.
《The Knee》2022
BackgroundIn recent years, transcatheter arterial embolization (TAE) using imipenem/cilastatin (IPM/CS) has attracted attention as a treatment for relieving osteoarthritis (OA) pain. However, IPM/CS is not approved by Japanese medical insurance for use as an embolic material. Therefore, it is necessary to develop new embolic materials for TAE to relieve OA pain. The purpose of this study was to develop a swine model of knee arthritis and embolize abnormal neovessels (ANs) using two different embolic materials. We compared the embolic effects and tissue damage in knees.MethodsKnee arthritis was induced by intra-articular injection of papain into 12 knees in six female swine. The swine were divided into two groups of three swine each (six knees per group) for embolization of ANs in the knees with either IPM/CS or soluble gelatin sponge particles (SGSs). Three days after embolization, we compared the embolic effects using angiography and the tissue damage histopathologically.ResultsANs were observed in all 12 knees at 42 days after papain injection. The ANs disappeared and the patent arteries were recanalized 3 days after TAE in all 12 knees. Histopathological evaluation revealed synovitis changes, such as synovial thickening and inflammatory cell infiltration, in all 12 knees. There was no evidence of skin or muscle necrosis in either group. The appearance of ANs, recanalization of the parent arteries, and histopathological outcomes were not significantly different between the two groups.ConclusionSGSs were as safe as IPM/CS for TAE of ANs in this swine model of knee arthritis. 相似文献