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排序方式: 共有2210条查询结果,搜索用时 234 毫秒
1.
Oxidative stress and inflammation are two possible mechanisms related to nephrotoxicity caused by environmental pollutants. Ellagic acid, a powerful antioxidant phytochemical, may have great relevance in mitigating pollutant-induced nephrotoxicity and preventing the progression of kidney disease. This review discusses the latest findings on the protective effects of ellagic acid, its metabolic derivatives, the urolithins, against kidney toxicity caused by heavy metals, pesticides, mycotoxins, and organic air pollutants. We describe the chelating, antioxidant, anti-inflammatory, antifibrotic, antiautophagic, and antiapoptotic properties of ellagic acid to attenuate nephrotoxicity. Furthermore, we present the molecular targets and signaling pathways that are regulated by these antioxidants, and suggest some others that should be explored. Nevertheless, the number of reports is still limited to establish the efficacy of ellagic acid against kidney damage induced by environmental pollutants. Therefore, additional preclinical studies on this topic are required, as well as the development of well-designed clinical trials. 相似文献
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BackgroundHeavy metal contamination has become a serious issue in this century especially detected in fish organs. Due to the presence of radioactive compounds in agricultural and sewage effluent, which destroys aquatic ecosystems, threatening human livelihoods. Health hazards associated with low and high consumption consumers assessed in five commercial fish species collected from Hurghada City, Egypt, during winter and summer, 2020. Atomic absorption spectrophotometer technique used for determination heavy meals in different organs and expressed as μg/g wet weight.ResultsHeavy metal concentrations in muscle ranged between:(0.054–0.109), (0.260–1.043), (0.264–0.897), (5.895–11.898), (0.381–0.970), (13.582–29.133) and (0.332–0.589) µg/g for Cd, Pb, Mn, Zn, Cu, Fe and Ni respectively, which were lower than those of gills and liver. These concentrations were within WHO, FAO/WHO, and EU standards. Consumption of edible species was lower than the (TDIs) established by the (JECFA) and Egyptian Standards. Even though THQ and TTHQ values were < 1 while, in children with highly consumer were> 1.ConclusionThis study concluded that intake of Red Sea fish is safe for human health. It is critical for consumers to be aware of the consequences of excessive fish consumption, particularly children with highly consumer, which represent possible health risks. 相似文献
4.
Devagi Kanakaraju Nurfatyha Rusydah bt Mohamad Shahdad Ying-Chin Lim Andrea Pace 《Sustainable Chemistry and Pharmacy》2019
The use of multifunctional materials for water remediation is a modern approach where adsorption phenomena and heterogeneous photocatalysis can be applied for the removal of pollutants. Since the ideal remediation system should be able to remove both organic and inorganic pollutants, a crucial aspect to consider is the knowledge of operational parameters affecting the removal process, especially when heavy metal ions are present in concoction as in real systems. Given the proven efficiency of multifunctional TiO2/Alg/FeNPs magnetic beads for the removal of model organic pollutants, this study investigated the possibility to exploit such system also for the removal of mixed heavy metals (MHM), specifically Cr(III), Cu(II), and Pb(II) ions, under ultraviolet irradiation at a wavelength of 254 nm. After a preliminary screening on the optimal catalyst loading, operating parameters such as the initial concentration of metal ions, contact and irradiation time, and pH were investigated to optimize the removal of metal ions using response surface methodology (RSM) via Box–Behnken design. Starting from a MHM solution containing 44 ppm of each metal ion, the removal of Pb(II), Cr(III), and Cu(II) ions in the aqueous solution was nearly completed (>98.4%) for all three ions within 72 min of irradiation at almost neutral pH (pH = 6.8). The stability of TiO2/Alg/FeNPs was confirmed by retrieving and reusing the beads in three consecutive cycles of heavy metals removal without observing significant changes in catalyst efficiency. 相似文献
5.
目的 测定珊瑚七十味丸(Ratanasampil,RNSP)中5种重金属元素的含量,并确定Hg元素存在的各种化学形态,为名贵藏药重金属含量及元素形态的确定提供准确的新型研究方法。方法 采用强酸消解法处理珊瑚七十味丸,利用电感耦合等离子体原子发射光谱(Inductively coupled plasma atomic emission spectrometry,ICP-OES)测定样品中不同重金属元素的含量,同时采用X射线光电子能谱技术(X-ray photoelectron spectroscopy,XPS)对样品中的Hg元素进行价态分析。结果 不同批次的珊瑚七十味丸中Hg、As、Cr、Cd及Cu这5种重金属元素含量存在一定的差异;Hg元素存在游离Hg2+、HgS、HgO共3种形式,且差异较大。结论 ICP-OES和XPS对药物中的5种重金属含量和Hg元素的价态进行的检测和分析,得到的数据较为准确、可靠,能够为珊瑚七十味丸的临床使用提供数据上的参考依据,也为传统道地藏药材中的重金属含量检测及价态分析提供了一种新的研究思路和方法。 相似文献
6.
目的:测定冰黄肤乐软膏中无机元素的含量,提出重金属元素的限量标准,为冰黄肤乐软膏的质量标准的完善和中医临床用药安全提供参考。方法:通过采用微波消解-电感耦合等离子体质谱法对冰黄肤乐软膏的无机元素进行测定和分析。结果:建立了冰黄肤乐软膏中24种无机元素的含量测定方法,精密度、稳定性、重复性、加样回收实验结果均符合药典相关规定。结论:建立的冰黄肤乐软膏无机元素检测方法可行,为冰黄肤乐软膏的质量标准的完善和临床用药安全提供参考。 相似文献
7.
Wajid Ali Khan Muhammad Balal Arain Yadollah Yamini Nasrullah Shah Tasneem Gul Kazi Stig Pedersen-Bjergaard Mohammad Tajik 《Journal of Pharmaceutical Analysis》2020,10(2):109-122
Hollow-fiber liquid-phase microextraction(HF-LPME)and electromembrane extraction(EME)are miniaturized extraction techniques,and have been coupled with various analytical instruments for trace analysis of heavy metals,drugs and other organic compounds,in recent years.HF-LPME and EME provide high selectivity,efficient sample cleanup and enrichment,and reduce the consumption of organic sol-vents to a few micro-liters per sample.HF-LPME and EME are compatible with different analytical in-struments for chromatography,electrophoresis,atomic spectroscopy,mass spectrometry,and electrochemical detection.HF-LPME and EME have gained significant popularity during the recent years.This review focuses on hollow fiber based techniques(especially HF-LPME and EME)of heavy metals and pharmaceuticals(published 2017 to May 2019),and their combinations with atomic spectroscopy,UV-VIS spectrophotometry,high performance liquid chromatography,gas chromatography,capillary elec-trophoresis,and voltammetry. 相似文献
8.
《Clinical Lymphoma, Myeloma & Leukemia》2020,20(8):493-498
Heavy chain disorders are rare B-cell disorders and include heavy chain disease, heavy chain deposition disease, and heavy chain amyloidosis. These disorders share the pathognomonic finding of a truncated immunoglobulin heavy chain without an associated light chain in the serum or urine in the case of heavy chain disease or in the tissues in the case of heavy chain deposition disease and heavy chain amyloidosis but are clinically distinct entities. The clinical recognition and systematic approaches to these disorders are challenging because of the rarity of the diseases, lack of consensus on treatment approaches, and minimal data with novel therapy. Herein we present a review of the literature and 5 consecutive cases at a single institution of gamma heavy chain disease and heavy chain deposition disease treated with novel agents including regimens of CRd (cyclophosphamide, lenalidomide, and dexamethasone), CyBorD (cyclophosphamide, bortezomib, and dexamethasone), R-CVP (rituximab, cyclophosphamide, vincristine, and dexamethasone), BR (bendamustine and rituximab), V-EPOCH (bortezomib, etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin), and autologous hematopoietic stem cell transplantation. 相似文献
9.
Exposure to trace metals may impact reproductive health outcomes through perturbations in maternal immune signaling molecules. We conducted a cross-sectional study of 390 pregnant women from the LIFECODES birth cohort and investigated the associations between 17 urinary metals and five immune biomarkers measured in the 3rd trimester (median 26 weeks gestation). We used linear regression to estimate pair-wise associations and applied elastic net and Bayesian kernel machine regression to identify important contributing exposures analytes as well as non-linear effects. Maternal urinary manganese, nickel, and barium were positively associated with maternal plasma interleukin-1β (IL-1β). Elastic net and Bayesian kernel machine regression identified manganese as the dominant trace metal in association with IL-1β. An interquartile range difference in manganese (0.6 μg/L) was associated with a 29 % increase in IL-1β (95 % CI: 12.4–48.2). In conclusion, trace metal exposures were associated with biomarkers of immune perturbations, and this warrants further investigation. 相似文献
10.
Richard Stanwick 《Paediatrics & child health》2015,20(2):101-105
An electronic cigarette (e-cigarette) is a battery attached to a chamber containing liquid that may (or may not) contain nicotine. The battery heats the liquid and converts it into a vapour, which is inhaled, mimicking tobacco smoking. The e-cigarette does not rely on tobacco as a source of nicotine but, rather, vaporizes a liquid for inhalation. E-liquids are often flavoured and may contain nicotine in various concentrations, although actual amounts are seldom accurately reflected in container labelling. The deleterious effects of nicotine on paediatric health are well established. The use of e-cigarettes in the paediatric age group is on the rise in Canada, as are associated nicotine poisonings. E-devices generate substantial amounts of fine particulate matter, toxins and heavy metals at levels that can exceed those observed for conventional cigarettes. Children and youth are particularly susceptible to these atomized products. Action must be taken before these devices become a more established public health hazard. Policies to denormalize tobacco smoking in society and historic reductions in tobacco consumption may be undermined by this new ‘gateway’ product to nicotine dependency. 相似文献