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Rapid industrial and technological development has impacted ecosystem homeostasis strongly. Arsenic is one of the most detrimental environmental toxins and its management with chelating agents remains a matter of concern due to associated adverse effects. Thus, safer and more effective alternative therapy is required to manage arsenic toxicity. Based on existing evidence, native and indigenous plant-based active biomolecules appear as a promising strategy to mitigate arsenic-induced toxicity with an acceptable safety profile. In this regard, various phytochemicals (flavonoids and stilbenoids) are considered important classes of polyphenolic compounds with antioxidant and chelation effects, which may facilitate the removal of arsenic from the body more effectively and safely with regard to conventional approaches. This review presents an overview of conventional chelating agents and the potential role of flavonoids and stilbenoids in ameliorating arsenic toxicity. This report may provide a roadmap for identifying novel prophylactic/therapeutic strategies for managing arsenic toxicity. 相似文献
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《Journal of pharmaceutical sciences》2019,108(7):2349-2357
Cocrystallization and salt formation were used to produce new multicomponent forms of a novel antimalarial imidazopyridazine drug lead (MMV652103) that displayed improved physicochemical properties. The drug lead had earlier shown good in vitro potency against multidrug resistant (K1) and sensitive (NF54) strains of the human malaria parasite Plasmodium falciparum, and high in vivo efficacy in both Plasmodium berghei and Plasmodium falciparum mouse models. A major drawback of MMV652103 is its limited aqueous solubility. Various new supramolecular products, including several multicomponent solid forms, are reported here, namely 3 cocrystal forms with the dicarboxylic acid coformers adipic acid, glutaric acid, and fumaric acid, and a salt form with malonic acid. These were characterized by thermal methods and their structures elucidated by single-crystal X-ray diffraction. A customized solubility experiment was performed in fasted-state simulated intestinal fluid for comparison of the solubility behavior of each new form of the drug lead with that of the untreated starting material. All of the multicomponent forms showed an improvement in the maximum concentrations (Cmax) attained by the drug lead and the rate at which it dissolved. The recorded Cmax values exceeded the concentration of the untreated compound by factors in the range 4.6-5.6. 相似文献
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Shakil Saba Muhammad Sajid Hamid Akash Kanwal Rehman Uzma Saleem Fareeha Fiayyaz Tanvir Ahmad 《Clinical and experimental pharmacology & physiology》2020,47(10):1682-1691
Arsenic (As) and cadmium (Cd) have recently emerged as major health concerns owing to their strong association with diabetes mellitus (DM). We aimed to investigate the heavy metals exposure towards incidence of DM at various enzymatic and hormonal levels. Additionally, association of As and Cd with Zinc (Zn, essential metal) was also evaluated. Spot urine samples were collected to assess As, Cd and Zn through ICP-OES. Serum was analyzed by assay method for fasting blood glucose, liver and renal function biomarkers. ELISA was performed to investigate the impact of heavy metals on HbA1c, α-amylase, DPP-IV, IGF-1, leptin, GSH, MDA, SOD, HDL, FFA, TG and interleukin (IL)-6. Association of heavy metals with DM was measured by odds ratio (OR) and level of significance was assessed by Chi-squared test. Unpaired student's t-test was used to compare DM-associated risk factors in heavy metals-exposed and unexposed participants. As and Cd were detectable in 75.4% and 83% participants with mean concentration of 75.5 ppb and 54.5 ppb, respectively. For As exposure, OR in the third quartile was maximum ie 1.34 (95% CI, 0.80 to 2.23), however the result was not statistically significant (P > .05). For Cd exposure, OR in the fourth quartile was considerably high, 1.62 (95% CI, 1.00 to 2.61), with a significant probability value (P < .05). Urinary Cd was negatively associated with Zn. As and Cd exposure increases the incidence of DM in the general population. Impaired hormonal and enzymatic levels in diabetic and non-diabetic exposed participants reflect the multiple organ damage by heavy metal exposure. 相似文献
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目的 以2017年某省食品安全监测大米中砷含量数据为例,探讨空间统计学方法在食品污染物分析中的应用价值。方法 采用空间点模式估计、核密度分析,全局以及局部自相关性分析等空间统计学方法,在县级空间尺度下,对某省大米中砷含量进行探索性空间数据分析。结果 空间点模式分布图显示,该省大米砷污染的空间分布比较分散,核密度分析结果显示污染热点区域主要在该省中东部地区。全局自相关Moran''s I指数值为0.11,有统计学意义,大米样品中砷污染呈现出低度空间聚集性。有1个"高-高"聚集区,2个典型的"低-低"聚集区。结论 空间统计学运用于食物污染物分布研究上,可以很好地可视化展示、识别污染分布规律、热点地区和聚集区,为基于问题的监测工作的开展提供技术支持。 相似文献
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三氧化二砷联合全反式维甲酸治疗急性早幼粒细胞白血病的初步观察 总被引:32,自引:0,他引:32
目的 观察三氧化二砷 (As2 O3 )联合全反式维甲酸 (ATRA)治疗急性早幼粒细胞白血病(APL)的疗效和不良反应。方法 As2 O3 联合ATRA治疗初治和复发APL患者 2 0例 (可评价的患者 18例 )。治疗方法如下 :As2 O3 (0 .1%溶液 ) 10ml加入 5 0g L葡萄糖溶液 5 0 0ml静脉点滴 ,持续 4~ 6h ,1次 d ;ATRA 2 5mg·m- 2 ·d- 1 ,分 2~ 3次服用。结果 17例患者获得完全缓解 (CR) ,CR率 94.4%。 14例初治患者均获得CR ,4例复发患者中 3例取得CR。均在 30d内达CR。没有发现明显的不良反应。结论 ATRA联合As2 O3 治疗APL患者不仅能获得好的疗效 ,而且能缩短达CR的时间。 相似文献
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目的研究三氧化二砷在体外对人骨肉瘤细胞(U2-OS)形态及细胞凋亡的影响。方法以不同浓度三氧化二砷(0.5、1.0、1.5μmol/L)作用骨肉瘤细胞,15 mg/L 5-FU作为阳性对照,采用荧光显微镜观察细胞核形态及流式细胞仪检测细胞凋亡率。结果各浓度的三氧化二砷对骨肉瘤细胞(U2-OS)的形态均有影响,随着三氧化二砷浓度的升高,细胞核发生固缩越明显,细胞凋亡率越高,与正常对照组相比,差异具统计学意义。结论三氧化二砷可导致骨肉瘤细胞(U2-OS)细胞核发生固缩坏死和凋亡,凋亡率与三氧化二砷浓度有依赖关系,在一定浓度范围内随浓度增高而增高。 相似文献