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  1. Arsenic | Cancer Trends Progress Report

    Science.gov (United States)

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  2. Disruption of Mitotic Progression by Arsenic.

    Science.gov (United States)

    States, J Christopher

    2015-07-01

    Arsenic is an enigmatic xenobiotic that causes a multitude of chronic diseases including cancer and also is a therapeutic with promise in cancer treatment. Arsenic causes mitotic delay and induces aneuploidy in diploid human cells. In contrast, arsenic causes mitotic arrest followed by an apoptotic death in a multitude of virally transformed cells and cancer cells. We have explored the hypothesis that these differential effects of arsenic exposure are related by arsenic disruption of mitosis and are differentiated by the target cell's ability to regulate or modify cell cycle checkpoints. Functional p53/CDKN1A axis has been shown to mitigate the mitotic block and to be essential to induction of aneuploidy. More recent preliminary data suggest that microRNA modulation of chromatid cohesion also may play a role in escape from mitotic block and in generation of chromosomal instability. Other recent studies suggest that arsenic may be useful in treatment of solid tumors when used in combination with other cytotoxic agents such as cisplatin.

  3. Arsenic

    Science.gov (United States)

    Arsenic is a natural element found in soil and minerals. Arsenic compounds are used to preserve wood, as pesticides, and in some industries. Arsenic can get into air, water, and the ground from wind- ...

  4. Arsenic Biotransformation as a Cancer Promoting Factor by Inducing DNA Damage and Disruption of Repair Mechanisms

    Directory of Open Access Journals (Sweden)

    Victor D. Martinez

    2011-01-01

    Full Text Available Chronic exposure to arsenic in drinking water poses a major global health concern. Populations exposed to high concentrations of arsenic-contaminated drinking water suffer serious health consequences, including alarming cancer incidence and death rates. Arsenic is biotransformed through sequential addition of methyl groups, acquired from s-adenosylmethionine (SAM. Metabolism of arsenic generates a variety of genotoxic and cytotoxic species, damaging DNA directly and indirectly, through the generation of reactive oxidative species and induction of DNA adducts, strand breaks and cross links, and inhibition of the DNA repair process itself. Since SAM is the methyl group donor used by DNA methyltransferases to maintain normal epigenetic patterns in all human cells, arsenic is also postulated to affect maintenance of normal DNA methylation patterns, chromatin structure, and genomic stability. The biological processes underlying the cancer promoting factors of arsenic metabolism, related to DNA damage and repair, will be discussed here.

  5. Arsenic

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    ... found in its pure form as a steel grey metal, arsenic is usually part of chemical compounds. ... imply endorsement by the American Cancer Society. No matter who you are, we can help. Contact us ...

  6. Arsenic induces structural and compositional colonic microbiome change and promotes host nitrogen and amino acid metabolism.

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    Dheer, Rishu; Patterson, Jena; Dudash, Mark; Stachler, Elyse N; Bibby, Kyle J; Stolz, Donna B; Shiva, Sruti; Wang, Zeneng; Hazen, Stanley L; Barchowsky, Aaron; Stolz, John F

    2015-12-15

    Chronic exposure to arsenic in drinking water causes cancer and non-cancer diseases. However, mechanisms for chronic arsenic-induced pathogenesis, especially in response to lower exposure levels, are unclear. In addition, the importance of health impacts from xeniobiotic-promoted microbiome changes is just being realized and effects of arsenic on the microbiome with relation to disease promotion are unknown. To investigate impact of arsenic exposure on both microbiome and host metabolism, the stucture and composition of colonic microbiota, their metabolic phenotype, and host tissue and plasma metabolite levels were compared in mice exposed for 2, 5, or 10weeks to 0, 10 (low) or 250 (high) ppb arsenite (As(III)). Genotyping of colonic bacteria revealed time and arsenic concentration dependent shifts in community composition, particularly the Bacteroidetes and Firmicutes, relative to those seen in the time-matched controls. Arsenic-induced erosion of bacterial biofilms adjacent to the mucosal lining and changes in the diversity and abundance of morphologically distinct species indicated changes in microbial community structure. Bacterical spores increased in abundance and intracellular inclusions decreased with high dose arsenic. Interestingly, expression of arsenate reductase (arsA) and the As(III) exporter arsB, remained unchanged, while the dissimilatory nitrite reductase (nrfA) gene expression increased. In keeping with the change in nitrogen metabolism, colonic and liver nitrite and nitrate levels and ratios changed with time. In addition, there was a concomitant increase in pathogenic arginine metabolites in the mouse circulation. These data suggest that arsenic exposure impacts the microbiome and microbiome/host nitrogen metabolism to support disease enhancing pathogenic phenotypes.

  7. Arsenic induces structural and compositional colonic microbiome change and promotes host nitrogen and amino acid metabolism

    Science.gov (United States)

    Dheer, Rishu; Patterson, Jena; Dudash, Mark; Stachler, Elyse N.; Bibby, Kyle J.; Stolz, Donna B.; Shiva, Sruti; Wang, Zeneng; Hazen, Stanley L.; Barchowsky, Aaron; Stolz, John F.

    2015-01-01

    Chronic exposure to arsenic in drinking water causes cancer and non-cancer diseases. However, mechanisms for chronic arsenic-induced pathogeneis, especially in response to lower exposure levels, are unclear. In addition, the importance of health impacts from xeniobiotic-promoted microbiome changes is just being realized and effects of arsenic on the microbiome with relation to disease promotion are unknown. To investigate impact of arsenic exposure on both microbiome and host metabolism, the stucture and composition of colonic microbiota, their metabolic phenotype, and host tissue and plasma metabolite levels were compared in mice exposed for 2, 5, or 10 weeks to 0, 10 (low) or 250 (high) ppb arsenite (As(III)). Genotyping of colonic bacteria revealed time and arsenic concentration dependent shifts in community composition, particularly the Bacteroidetes and Firmicutes, relative to those seen in the time-matched controls. Arsenic-induced erosion of bacterial biofilms adjacent to the mucosal lining and changes in the diversity and abundance of morphologically distinct species indicated changes in microbial community structure. Bacterical spores increased in abundance and intracellular inclusions decreased with high dose arsenic. Interestingly, expression of arsenate reductase (arsA) and the As(III) exporter arsB, remained unchanged, while the dissimilatory nitrite reductase (nrfA) gene expression increased. In keeping with the change in nitrogen metabolism, colonic and liver nitrite and nitrate levels and ratios changed with time. In addition, there was a concomitant increase in pathogenic arginine metabolites in the mouse circulation. These data suggest that arsenic exposure impacts the microbiome and microbiome/host nitrogen metabolism to support disease enhancing pathogenic phenotypes. PMID:26529668

  8. Stimulatory effects of arsenic-tolerant soil fungi on plant growth promotion and soil properties.

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    Srivastava, Pankaj Kumar; Shenoy, Belle Damodara; Gupta, Manjul; Vaish, Aradhana; Mannan, Shivee; Singh, Nandita; Tewari, Shri Krishna; Tripathi, Rudra Deo

    2012-01-01

    Fifteen fungi were obtained from arsenic-contaminated agricultural fields in West Bengal, India and examined for their arsenic tolerance and removal ability in our previous study. Of these, the four best arsenic-remediating isolates were tested for plant growth promotion effects on rice and pea in the present study. A greenhouse-based pot experiment was conducted using soil inocula of individual fungi. The results indicated a significant (Psoil properties in inoculated soils compared to the control. A significant increase in plant growth was recorded in treated soils and varied from 16-293%. Soil chemical and enzymatic properties varied from 20-222% and 34-760%, respectively, in inoculated soil. Plants inoculated with inocula of Westerdykella and Trichoderma showed better stimulatory effects on plant growth and soil nutrient availability than Rhizopus and Lasiodiplodia. These fungi improved soil nutrient content and enhanced plant growth. These fungi may be used as bioinoculants for plant growth promotion and improved soil properties in arsenic-contaminated agricultural soils.

  9. A Phytoremediation Strategy for Arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

    A Phytoremediation Strategy for Arsenic Progress Report May, 2005 Richard B. Meagher Principal Investigator Arsenic pollution affects the health of several hundred millions of people world wide, and an estimated 10 million Americans have unsafe levels of arsenic in their drinking water. However, few environmentally sound remedies for cleaning up arsenic contaminated soil and water have been proposed. Phytoremediation, the use of plants to extract and sequester environmental pollutants, is one new technology that offers an ecologically sound solution to a devastating problem. We propose that it is less disruptive to the environment to harvest and dispose of several thousand pounds per acre of contaminated aboveground plant material, than to excavate and dispose of 1 to 5 million pounds of contaminated soil per acre (assumes contamination runs 3 ft deep). Our objective is to develop a genetics-based phytoremediation strategy for arsenic removal that can be used in any plant species. This strategy requires the enhanced expression of several transgenes from diverse sources. Our working hypothesis is that organ-specific expression of several genes controlling the transport, electrochemical state, and binding of arsenic will result in the efficient extraction and hyperaccumulation of arsenic into aboveground plant tissues. This hypothesis is supported by theoretical arguments and strong preliminary data. We proposed six Specific Aims focused on testing and developing this arsenic phytoremediation strategy. During the first 18 months of the grant we made significant progress on five Specific Aims and began work on the sixth as summarized below. Specific Aim 1: Enhance plant arsenic resistance and greatly expand sinks for arsenite by expressing elevated levels of thiol-rich, arsenic-binding peptides. Hyperaccumulation of arsenic depends upon making plants that are both highly tolerant to arsenic and that have the capacity to store large amounts of arsenic aboveground

  10. Research progress on toxicity and excretion of arsenic%砷的毒性及排砷研究进展

    Institute of Scientific and Technical Information of China (English)

    李羡筠

    2012-01-01

    砷是有毒的类金属元素,通过环境污染和职业性接触进入体内,对人体的皮肤、神经系统、心血管、肝脏及肾脏等有明显的损伤.在砷中毒治疗中,常用临床药物虽然排砷效果好,但具有一定的局限性,寻求一种高效、价廉、无不良反应且能广泛用于患者的排砷药物是当务之急.笔者就近年来国内外学者有关砷对机体的损害及排砷治疗的研究进展进行综述.%Arsenic is a toxic metalloid element, it enter the body through environmental pollution and occupational exposure, and may cause an obvious damage on skin, nervous system, cardiovascular system, liver and kidney. In the treatment of arsenic poisoning, although the common drugs have good effect on excretion of arsenic, there are some limitations. It is the urgent affair to find out an arsenic excretion drug which has good effect, low cost, less adverse reaction and extensive use. This article reviews the research progress on damages caused by arsenic and excretion of arsenic at home and abroad.

  11. Evidence of arsenic release promoted by disinfection by-products within drinking-water distribution systems.

    Science.gov (United States)

    Andra, Syam S; Makris, Konstantinos C; Botsaris, George; Charisiadis, Pantelis; Kalyvas, Harris; Costa, Costas N

    2014-02-15

    Changes in disinfectant type could trigger a cascade of reactions releasing pipe-anchored metals/metalloids into finished water. However, the effect of pre-formed disinfection by-products on the release of sorbed contaminants (arsenic-As in particular) from drinking water distribution system pipe scales remains unexplored. A bench-scale study using a factorial experimental design was performed to evaluate the independent and interaction effects of trihalomethanes (TTHM) and haloacetic acids (HAA) on arsenic (As) release from either scales-only or scale-biofilm conglomerates (SBC) both anchored on asbestos/cement pipe coupons. A model biofilm (Pseudomonas aeruginosa) was allowed to grow on select pipe coupons prior experimentation. Either TTHM or HAA individual dosing did not promote As release from either scales only or SBC, detecting water. In the case of scales-only coupons, the combination of the highest spike level of TTHM and HAA significantly (pdisinfected finished water in pipe networks remains to be investigated in the field.

  12. Sustainable engineered processes to mitigate the global arsenic crisis in drinking water: challenges and progress.

    Science.gov (United States)

    Sarkar, Sudipta; Greenleaf, John E; Gupta, Anirban; Uy, Davin; Sengupta, Arup K

    2012-01-01

    Millions of people around the world are currently living under the threat of developing serious health problems owing to ingestion of dangerous concentrations of arsenic through their drinking water. In many places, treatment of arsenic-contaminated water is an urgent necessity owing to a lack of safe alternative sources. Sustainable production of arsenic-safe water from an arsenic-contaminated raw water source is currently a challenge. Despite the successful development in the laboratory of technologies for arsenic remediation, few have been successful in the field. A sustainable arsenic-remediation technology should be robust, composed of local resources, and user-friendly as well as must attach special consideration to the social, economic, cultural, traditional, and environmental aspects of the target community. One such technology is in operation on the Indian subcontinent. Wide-scale replication of this technology with adequate improvisation can solve the arsenic crisis prevalent in the developing world.

  13. Arsenic in private well water part 2 of 3: Who benefits the most from traditional testing promotion?

    Science.gov (United States)

    Flanagan, Sara V; Spayd, Steven E; Procopio, Nicholas A; Chillrud, Steven N; Ross, James; Braman, Stuart; Zheng, Yan

    2016-08-15

    Arsenic, a toxic element naturally found in groundwater, is a public health concern for households drinking from wells. Private well water is not regulated to meet the federal drinking water arsenic Maximum Contaminant Level (MCL) of 10μg/L, or the more protective 5μg/L New Jersey (NJ) state MCL. In the absence of consistent private well regulation, public health efforts have relied on promoting testing in affected communities to various degrees of success. Few interventions publish results, and more often focus on the outcome of tested wells rather than who completed a test, and more importantly, who did not. Through our survey of randomly selected addresses (n=670) in 17 NJ towns we find higher rates of arsenic testing in areas with a history of testing promotion. However, we also see a stronger correlation of testing behavior with income and education in high promotion areas, suggesting that community engagement activities may be exacerbating socioeconomic status (SES) testing disparities. Well owners with a bachelor's degree had ten times greater odds of participating in our direct mail testing intervention than those with less education when tests cost $40. After all households (n=255) were offered free tests to overcome many of the usual testing barriers - awareness, convenience, and cost - only 47% participated and those who chose to return water samples were of higher income and education than those who did not. Our findings highlight that while efforts to promote and provide arsenic testing succeed in testing more wells, community testing interventions risk increasing SES disparities if those with more education and resources are more likely to take advantage of testing programs. Therefore, testing interventions can benefit by better targeting socially vulnerable populations in an effort to overcome SES-patterned self-selection when individuals are left alone with the responsibility of managing their drinking water quality.

  14. NOTCH pathway inactivation promotes bladder cancer progression.

    Science.gov (United States)

    Maraver, Antonio; Fernandez-Marcos, Pablo J; Cash, Timothy P; Mendez-Pertuz, Marinela; Dueñas, Marta; Maietta, Paolo; Martinelli, Paola; Muñoz-Martin, Maribel; Martínez-Fernández, Mónica; Cañamero, Marta; Roncador, Giovanna; Martinez-Torrecuadrada, Jorge L; Grivas, Dimitrios; de la Pompa, Jose Luis; Valencia, Alfonso; Paramio, Jesús M; Real, Francisco X; Serrano, Manuel

    2015-02-01

    NOTCH signaling suppresses tumor growth and proliferation in several types of stratified epithelia. Here, we show that missense mutations in NOTCH1 and NOTCH2 found in human bladder cancers result in loss of function. In murine models, genetic ablation of the NOTCH pathway accelerated bladder tumorigenesis and promoted the formation of squamous cell carcinomas, with areas of mesenchymal features. Using bladder cancer cells, we determined that the NOTCH pathway stabilizes the epithelial phenotype through its effector HES1 and, consequently, loss of NOTCH activity favors the process of epithelial-mesenchymal transition. Evaluation of human bladder cancer samples revealed that tumors with low levels of HES1 present mesenchymal features and are more aggressive. Together, our results indicate that NOTCH serves as a tumor suppressor in the bladder and that loss of this pathway promotes mesenchymal and invasive features.

  15. CXCL5 Promotes Prostate Cancer Progression

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    Lesa A Begley

    2008-03-01

    Full Text Available CXCL5 is a proangiogenic CXC-type chemokine that is an inflammatory mediator and a powerful attractant for granulocytic immune cells. Unlike many other chemokines, CXCL5 is secreted by both immune (neutrophil, monocyte, and macrophage and nonimmune (epithelial, endothelial, and fibroblastic cell types. The current study was intended to determine which of these cell types express CXCL5 in normal and malignant human prostatic tissues, whether expression levels correlated with malignancy and whether CXCL5 stimulated biologic effects consistent with a benign or malignant prostate epithelial phenotype. The results of these studies show that CXCL5 protein expression levels are concordant with prostate tumor progression, are highly associated with inflammatory infiltrate, and are frequently detected in the lumens of both benign and malignant prostate glands. Exogenous administration of CXCL5 stimulates cellular proliferation and gene transcription in both nontransformed and transformed prostate epithelial cells and induces highly aggressive prostate cancer cells to invade through synthetic basement membrane in vitro. These findings suggest that the inflammatory mediator, CXCL5, may play multiple roles in the etiology of both benign and malignant proliferative diseases in the prostate.

  16. RECENT PROGRESS IN ARSENIC RESEARCH IN CHINA%中国关于砷的研究进展

    Institute of Scientific and Technical Information of China (English)

    陈保卫; Le X. Chris

    2011-01-01

    综述了近年来有关中国的砷污染状况、相关的分析监测技术及砷化合物毒性的研究进展.在中国部分地区,长期砷暴露导致了严重的区域性的砷中毒,主要的暴露途径是饮用水、食物和煤炭的燃烧.样品前处理、砷的富集和形态分析技术的丰富和发展,为环境科学、毒理学和流行病学的研究提供了可靠的技术支持.生物检测是一种直接有效的污染物健康风险评估方法,尿样、血液、唾液、头发和指甲中的砷及生理生化指标直接反映了暴露主体的砷暴露程度和砷相关的损伤程度.在砷的生物代谢过程中,产生活性氧和自由基,导致氧化应激的提高,影响亚铁血红蛋白的生物合成,导致细胞膜的过氧化,线粒体相关的细胞凋亡,DNA的氧化损伤而产生基因突变.砷中毒的易受程度,与年龄、营养状况、硒的摄入相关.砷化合物能穿过胎盘屏障影响胎儿的发育,穿过脑血屏障影响智力发育和导致神经毒性.慢性砷中毒的机理还有待进一步的研究.%This review summarizes recent research conducted on environmental arsenic in China,covering the topics of environmental contamination,human exposure,speciation analysis,biomonitoring,biotransformation,and toxicity of arsenic compounds.Chronic exposure to arsenic through ingestion of drinking water and contaminated food,and/or inhalation of contaminated air due to coal combustion is responsible for endemic arsenicosis in several areas of China.Progress has been made in analytical techniques for speciation analysis,increasing the number of studies on environmental chemistry,toxicology,and epidemiology of arsenic.Urine,blood,saliva,hair,and nail have been analyzed for arsenic species to assess arsenic exposure.Epidemiological,biochemical,and animal studies have linked excess arsenic exposure with the elevated levels of oxidation stress,as measured by oxidative damage to DNA and peroxidation of cell

  17. GT-repeat polymorphism in the heme oxygenase-1 gene promoter and the risk of carotid atherosclerosis related to arsenic exposure

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    Wu Meei-Maan

    2010-08-01

    Full Text Available Abstract Background Arsenic is a strong stimulus of heme oxygenase (HO-1 expression in experimental studies in response to oxidative stress caused by a stimulus. A functional GT-repeat polymorphism in the HO-1 gene promoter was inversely correlated to the development of coronary artery disease in diabetics and development of restenosis following angioplasty in patients. The role of this potential vascular protective factor in carotid atherosclerosis remains unclear. We previously reported a graded association of arsenic exposure in drinking water with an increased risk of carotid atherosclerosis. In this study, we investigated the relationship between HO-1 genetic polymorphism and the risk of atherosclerosis related to arsenic. Methods Three-hundred and sixty-seven participants with an indication of carotid atherosclerosis and an additional 420 participants without the indication, which served as the controls, from two arsenic exposure areas in Taiwan, a low arsenic-exposed Lanyang cohort and a high arsenic-exposed LMN cohort, were studied. Carotid atherosclerosis was evaluated using a duplex ultrasonographic assessment of the extracranial carotid arteries. Allelic variants of (GTn repeats in the 5'-flanking region of the HO-1 gene were identified and grouped into a short (S allele ( Results Analysis results showed that arsenic's effect on carotid atherosclerosis differed between carriers of the class S allele (OR 1.39; 95% CI 0.86-2.25; p = 0.181 and non-carriers (OR 2.65; 95% CI 1.03-6.82; p = 0.044 in the high-exposure LMN cohort. At arsenic exposure levels exceeding 750 μg/L, difference in OR estimates between class S allele carriers and non-carriers was borderline significant (p = 0.051. In contrast, no such results were found in the low-exposure Lanyang cohort. Conclusions This exploratory study suggests that at a relatively high level of arsenic exposure, carriers of the short (GTn allele (

  18. Epigenetic targets of arsenic: emphasis on epigenetic modifications during carcinogenesis.

    Science.gov (United States)

    Roy, Ram Vinod; Son, Young-Ok; Pratheeshkumar, Poyil; Wang, Lei; Hitron, John Andrew; Divya, Sasidharan Padmaja; D, Rakesh; Kim, Donghern; Yin, Yuanqin; Zhang, Zhuo; Shi, Xianglin

    2015-01-01

    DNA methylation and histone modification promote opening and closure of chromatin structure, which affects gene expression without altering the DNA sequence. Epigenetic markers regulate the dynamic nature of chromatin structure at different levels: DNA, histone, noncoding RNAs, as well as the higher-order chromatin structure. Accumulating evidence strongly suggests that arsenic-induced carcinogenesis involves frequent changes in the epigenetic marker. However, progress in identifying arsenic-induced epigenetic changes has already been made using genome-wide approaches; the biological significance of these epigenetic changes remains unknown. Moreover, arsenic-induced changes in the chromatin state alter gene expression through the epigenetic mechanism. The current review provides a summary of recent literature regarding epigenetic changes caused by arsenic in carcinogenesis. We highlight the transgenerational studies needed to explicate the biological significance and toxicity of arsenic over a broad spectrum.

  19. A cluster-based randomized controlled trial promoting community participation in arsenic mitigation efforts in Bangladesh

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    George Christine

    2012-06-01

    Full Text Available Abstract Objective To reduce arsenic (As exposure, we evaluated the effectiveness of training community members to perform water arsenic (WAs testing and provide As education compared to sending representatives from outside communities to conduct these tasks. Methods We conducted a cluster based randomized controlled trial of 20 villages in Singair, Bangladesh. Fifty eligible respondents were randomly selected in each village. In 10 villages, a community member provided As education and WAs testing. In a second set of 10 villages an outside representative performed these tasks. Results Overall, 53% of respondents using As contaminated wells, relative to the Bangladesh As standard of 50 μg/L, at baseline switched after receiving the intervention. Further, when there was less than 60% arsenic contaminated wells in a village, the classification used by the Bangladeshi and UNICEF, 74% of study households in the community tester villages, and 72% of households in the outside tester villages reported switching to an As safe drinking water source . Switching was more common in the outside-tester (63% versus community-tester villages (44%. However, after adjusting for the availability of arsenic safe drinking water sources, well switching did not differ significantly by type of As tester (Odds ratio =0.86[95% confidence interval 0.42-1.77. At follow-up, among those using As contaminated wells who switched to safe wells, average urinary As concentrations significantly decreased. Conclusion The overall intervention was effective in reducing As exposure provided there were As-safe drinking water sources available. However, there was not a significant difference observed in the ability of the community and outside testers to encourage study households to use As-safe water sources. The findings of this study suggest that As education and WAs testing programs provided by As testers, irrespective of their residence, could be used as an effective, low cost

  20. New Progress in the Treatment of Wastewater Containing Arsenic%含砷废水处理新进展

    Institute of Scientific and Technical Information of China (English)

    张伟

    2012-01-01

    含砷废水的传统处理方法,如物理法和化学法的不足之处在于费用高,二次污染大,工程化程度小。生物法在含砷废水处理方面有着广阔的应用前景,并取得了显著进展,特别是生物膜、活性污泥、生物吸附、生物滤池等处理工艺,研究成果已投入工程应用。对近年来含砷废水处理方法的进展进行了综述,并对合砷废水的处理方法进行了展望。%Physical and chemical methodologies are traditional ways in treating the wastewater containing the arsenic. The high cost, secondary pollution and low engineering level are their disadvantages. Biological methodology has a promising application prospect with a great progress, particularly those treatment processes such as biofilms, activated sludge, bio- absorption, and biofihers. Its research results have been put into engineering practice. A review and outlook of the development of the arsenic wastewater treatment methodologies are presented in this paper.

  1. Fascin overexpression promotes neoplastic progression in oral squamous cell carcinoma

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    Alam Hunain

    2012-01-01

    Full Text Available Abstract Background Fascin is a globular actin cross-linking protein, which plays a major role in forming parallel actin bundles in cell protrusions and is found to be associated with tumor cell invasion and metastasis in various type of cancers including oral squamous cell carcinoma (OSCC. Previously, we have demonstrated that fascin regulates actin polymerization and thereby promotes cell motility in K8-depleted OSCC cells. In the present study we have investigated the role of fascin in tumor progression of OSCC. Methods To understand the role of fascin in OSCC development and/or progression, fascin was overexpressed along with vector control in OSCC derived cells AW13516. The phenotype was studied using wound healing, Boyden chamber, cell adhesion, Hanging drop, soft agar and tumorigenicity assays. Further, fascin expression was examined in human OSCC samples (N = 131 using immunohistochemistry and level of its expression was correlated with clinico-pathological parameters of the patients. Results Fascin overexpression in OSCC derived cells led to significant increase in cell migration, cell invasion and MMP-2 activity. In addition these cells demonstrated increased levels of phosphorylated AKT, ERK1/2 and JNK1/2. Our in vitro results were consistent with correlative studies of fascin expression with the clinico-pathological parameters of the OSCC patients. Fascin expression in OSCC showed statistically significant correlation with increased tumor stage (P = 0.041, increased lymph node metastasis (P = 0.001, less differentiation (P = 0.005, increased recurrence (P = 0.038 and shorter survival (P = 0.004 of the patients. Conclusion In conclusion, our results indicate that fascin promotes tumor progression and activates AKT and MAPK pathways in OSCC-derived cells. Further, our correlative studies of fascin expression in OSCC with clinico-pathological parameters of the patients indicate that fascin may prove to be useful in prognostication and

  2. The present treatment and mechanism progress of arsenic trioxide in hematological malignancies

    Institute of Scientific and Technical Information of China (English)

    Lin Liu; Zhi-Gang Zhao

    2016-01-01

    Arsenic trioide (ATO) is a kind of highly toxic substances and the main effective components of arsenic. ATO has been used medicinally for over 2400 years. Recent years, many studies have found that ATO has a significant efficacy on the acute promyelocytic leukemia (APL). To further explore the latest findings of research on the treatment of hematologic malignanies of ATO, this paper reviewed the development history of ATO, and summarized its mechanisms and clinical application in the treatment of hematologic malignancies. In addition, we want to provide new ideas for researches on the treatment of cancer of ATO.%三氧化二砷(ATO)是一种剧毒物质,又是中药砒霜的主要成分,人类用它作为药物治疗疾病已有2400多年的历史。近年来发现ATO对急性早幼粒细胞性白血病(APL)具有显著的疗效。为进一步了解ATO治疗血液系统恶性肿瘤作用的研究近况,本文回顾ATO的研发历史,并总结其在治疗血液恶性肿瘤中的作用机制及临床应用,以期为ATO治疗肿瘤方面的研究提供新的思路。

  3. Research progress in detection methods of arsenic and arsenic speciation%砷及砷的形态检测方法的研究现状

    Institute of Scientific and Technical Information of China (English)

    张金玲; 钟耀广; 孙晓红; 邓健康; 林栋

    2012-01-01

    砷是一种广泛分布于自然界的微量元素,摄入过量砷元素容易引起砷的急性中毒而致死,应引起人们足够的重视。砷的毒性主要取决于它的化学形态,形态不同毒性差异很大,所以选择适当、简便、快速的测定方法是现代分析技术取得发展的必要条件。本文综述了近年来砷及其形态常用的测定方法,并且分析了各检测方法的优缺点,展望了砷及其形态检测技术的发展前景。%Arsenic,a kind of trace elements, is widely distributed in nature. Excessive arsenic intake can lead to acute poisoning and even to death, which should arouse the society' s enough attention and awareness. The toxicity of arsenic compounds is mainly determined by its chemical speciation, and the toxicity of arsenic in different speciation varies greatly.It is essential for the development of modern analytical techniques that selecting the appropriate,simple and rapid determination method.Some common methods for the determination of arsenic and its speciation were reviewed and the advantages and disadvantages of various detection methods were analyzed.The article prospected the research on detection technique of arsenic and its speciation.

  4. Morphine Promotes Tumor Angiogenesis and Increases Breast Cancer Progression

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    Sabrina Bimonte

    2015-01-01

    Full Text Available Morphine is considered a highly potent analgesic agent used to relieve suffering of patients with cancer. Several in vitro and in vivo studies showed that morphine also modulates angiogenesis and regulates tumour cell growth. Unfortunately, the results obtained by these studies are still contradictory. In order to better dissect the role of morphine in cancer cell growth and angiogenesis we performed in vitro studies on ER-negative human breast carcinoma cells, MDA.MB231 and in vivo studies on heterotopic mouse model of human triple negative breast cancer, TNBC. We demonstrated that morphine in vitro enhanced the proliferation and inhibited the apoptosis of MDA.MB231 cells. In vivo studies performed on xenograft mouse model of TNBC revealed that tumours of mice treated with morphine were larger than those observed in other groups. Moreover, morphine was able to enhance the neoangiogenesis. Our data showed that morphine at clinical relevant doses promotes angiogenesis and increases breast cancer progression.

  5. Embryonic morphogen nodal promotes breast cancer growth and progression.

    Directory of Open Access Journals (Sweden)

    Daniela F Quail

    Full Text Available Breast cancers expressing human embryonic stem cell (hESC-associated genes are more likely to progress than well-differentiated cancers and are thus associated with poor patient prognosis. Elevated proliferation and evasion of growth control are similarly associated with disease progression, and are classical hallmarks of cancer. In the current study we demonstrate that the hESC-associated factor Nodal promotes breast cancer growth. Specifically, we show that Nodal is elevated in aggressive MDA-MB-231, MDA-MB-468 and Hs578t human breast cancer cell lines, compared to poorly aggressive MCF-7 and T47D breast cancer cell lines. Nodal knockdown in aggressive breast cancer cells via shRNA reduces tumour incidence and significantly blunts tumour growth at primary sites. In vitro, using Trypan Blue exclusion assays, Western blot analysis of phosphorylated histone H3 and cleaved caspase-9, and real time RT-PCR analysis of BAX and BCL2 gene expression, we demonstrate that Nodal promotes expansion of breast cancer cells, likely via a combinatorial mechanism involving increased proliferation and decreased apopotosis. In an experimental model of metastasis using beta-glucuronidase (GUSB-deficient NOD/SCID/mucopolysaccharidosis type VII (MPSVII mice, we show that although Nodal is not required for the formation of small (<100 cells micrometastases at secondary sites, it supports an elevated proliferation:apoptosis ratio (Ki67:TUNEL in micrometastatic lesions. Indeed, at longer time points (8 weeks, we determined that Nodal is necessary for the subsequent development of macrometastatic lesions. Our findings demonstrate that Nodal supports tumour growth at primary and secondary sites by increasing the ratio of proliferation:apoptosis in breast cancer cells. As Nodal expression is relatively limited to embryonic systems and cancer, this study establishes Nodal as a potential tumour-specific target for the treatment of breast cancer.

  6. Cyr61 promotes breast tumorigenesis and cancer progression

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Miaw-Sheue; Bogart, Daphne F.; Castaneda, Jessica M.; Li, Patricia; Lupu, Ruth

    2002-01-16

    Cyr61, a member of the CCN family of genes, is an angiogenic factor. We have shown that it is overexpressed in invasive and metastatic human breast cancer cells and tissues. Here, we investigated whether Cyr61 is necessary and/or sufficient to bypass the ''normal'' estrogen (E2) requirements for breast cancer cell growth. Our results demonstrate that under E2-depleted condition, Cyr61 is sufficient to induce MCF-7 cells grow in the absence of E2. MCF-7 cells transfected with Cyr61 (MCF-7/Cyr61) became E2-independent but still E2-responsive. On the other hand, MCF-7/vector cells remain E2-dependent. MCF-7/Cyr61 cells acquire an antiestrogen-resistant phenotype, one of the most common clinical occurrences during breast cancer progression. MCF-7/Cyr61 cells are anchorage-independent and capable of forming Matrigel outgrowth patterns in the absence of E2. ERa expression in MCF-7/Cyr61 cells is decreased although still functional. Additionally, MCF-7/Cyr61 cells are tumorigenic in ovariectomized athymic nude mice. The tumors resemble human invasive carcinomas with increased vascularization and overexpression of vascular endothelial growth factor (VEGF). Our results demonstrate that Cyr61 is a tumor-promoting factor and a key regulator of breast cancer progression. This study provides evidence that Cyr61 is sufficient to induce E2-independence and anti-E2 resistance, and to promote invasiveness in vitro, and to induce tumorigenesis in vivo, all of which are characteristics of an aggressive breast cancer phenotype.

  7. Arsenic trioxide promotes senescence and regulates the balance of adipogenic and osteogenic differentiation in human mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Huanchen Cheng; Lin Qiu; Hao Zhang; Mei Cheng; Wei Li; Xuefei Zhao; Keyu Liu; Lei Lei; Jun Ma

    2011-01-01

    Arsenic trioxide (ATO) as an anti-tumor drug could induce differentiation and apoptosis in tumor cells.Mesenchymal stem cells (MSCs) play important roles in the hematogenesis of bone marrow. Many reports have shown that the disorder of MSC adipogenic and osteogenic differentiation occurs in some diseases. However,reports about the effects of ATO on MSCs are limited. In this study, we found that 1μM ATO promoted MSC senescence mainly through p21, although it had no effect on apoptosis at this dose. Furthermore, ATO promoted adipogenic differentiation, but inhibited osteogenic differentiation in MSCs. Our study also showed that CCAAT/enhancer-binding protein alpha C/EBPα and peroxisome proliferator-activated receptor gamma PPARγ might be involved in the regulation of adipogenic and osteogenic differentiation induced by ATO. Our results indicated that ATO may exert an anti-tumor effect by influencing bone marrow micro-environment. Moreover, it may regulate the adipogenic and osteogenic differentiation of MSCs.

  8. Arsenic promotes ubiquitinylation and lysosomal degradation of cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels in human airway epithelial cells.

    Science.gov (United States)

    Bomberger, Jennifer M; Coutermarsh, Bonita A; Barnaby, Roxanna L; Stanton, Bruce A

    2012-05-18

    Arsenic exposure significantly increases respiratory bacterial infections and reduces the ability of the innate immune system to eliminate bacterial infections. Recently, we observed in the gill of killifish, an environmental model organism, that arsenic exposure induced the ubiquitinylation and degradation of cystic fibrosis transmembrane conductance regulator (CFTR), a chloride channel that is essential for the mucociliary clearance of respiratory pathogens in humans. Accordingly, in this study, we tested the hypothesis that low dose arsenic exposure reduces the abundance and function of CFTR in human airway epithelial cells. Arsenic induced a time- and dose-dependent increase in multiubiquitinylated CFTR, which led to its lysosomal degradation, and a decrease in CFTR-mediated chloride secretion. Although arsenic had no effect on the abundance or activity of USP10, a deubiquitinylating enzyme, siRNA-mediated knockdown of c-Cbl, an E3 ubiquitin ligase, abolished the arsenic-stimulated degradation of CFTR. Arsenic enhanced the degradation of CFTR by increasing phosphorylated c-Cbl, which increased its interaction with CFTR, and subsequent ubiquitinylation of CFTR. Because epidemiological studies have shown that arsenic increases the incidence of respiratory infections, this study suggests that one potential mechanism of this effect involves arsenic-induced ubiquitinylation and degradation of CFTR, which decreases chloride secretion and airway surface liquid volume, effects that would be proposed to reduce mucociliary clearance of respiratory pathogens.

  9. Research Progress of the Arsenic-containing Refractory Gold Flotation%含砷难处理金矿浮选研究进展

    Institute of Scientific and Technical Information of China (English)

    沈述保; 唐明刚

    2014-01-01

    随着易处理单一金矿储量不断减少,含砷难处理金矿所占比重越来越大。此类矿石普遍采用浮选法处理,总结含砷难处理矿石浮选技术研究进展有重要意义。浮选药剂的研发是含砷金矿分选技术的重点,近年来高选择性捕收剂和砷抑制剂的研发和应用取得了较多进展,浮选工艺研究也取得了创新性成果,而新型捕收剂及砷抑制剂的研究应用和浮选联合工艺开发是未来含砷难处理金矿研究的主要方向。%With the increasingly exhausting of easily leachable gold ores,the proportion of refractory gold ores which containing arsenic is growing larger.The ores were dealt commonly with the flotation method,and summarizing the flotation technology of refractory gold ores which containing arsenic is very important. Obviously,research and development of the flotation reagent is the key to the flotation technology of the containing arsenic gold ores.In recent years,it has made more progress for the development and application of the high selective collector and arsenic inhibitors.And the research on flotation also has made innovative achievements.In short,the development and application of the high selective collector and arsenic inhibitors and the exploitations of combined processes are the main directions for the research of refractory gold ores which containing arsenic.

  10. Endocrine fibroblast growth factor FGF19 promotes prostate cancer progression.

    Science.gov (United States)

    Feng, Shu; Dakhova, Olga; Creighton, Chad J; Ittmann, Michael

    2013-04-15

    Prostate cancer is the most common visceral malignancy and the second leading cause of cancer deaths in US men. There is broad evidence that fibroblast growth factor (FGF) receptors are important in prostate cancer initiation and progression, but the contribution of particular FGFs in this disease is not fully understood. The FGF family members FGF19, FGF21, and FGF23 comprise a distinct subfamily that circulate in serum and act in an endocrine manner. These endocrine FGFs require α-Klotho (KL) and/or β-Klotho (KLB), two related single-pass transmembrane proteins restricted in their tissue distribution, to act as coreceptors along with classic FGF receptors (FGFR) to mediate potent biologic activity. Here we show that FGF19 is expressed in primary and metastatic prostate cancer tissues, where it functions as an autocrine growth factor. Exogenous FGF19 promoted the growth, invasion, adhesion, and colony formation of prostate cancer cells at low ligand concentrations. FGF19 silencing in prostate cancer cells expressing autocrine FGF19 decreased invasion and proliferation in vitro and tumor growth in vivo. Consistent with these observations, KL and/or KLB were expressed in prostate cancer cells in vitro and in vivo, raising the possibility that additional endocrine FGFs may also exert biologic effects in prostate cancer. Our findings support the concept that therapies targeting FGFR signaling may have efficacy in prostate cancer and highlight FGF19 as a relevant endocrine FGF in this setting.

  11. Promotion of arsenic phytoextraction efficiency in the fern Pteris vittata by the inoculation of As-resistant bacteria: a soil bioremediation perspective.

    Directory of Open Access Journals (Sweden)

    Silvia eLampis

    2015-02-01

    Full Text Available A greenhouse pot experiment was carried out to evaluate the efficiency of arsenic phytoextraction by the fern Pteris vittata growing in arsenic-contaminated soil, with or without the addition of selected rhizobacteria isolated from the polluted site. The bacterial strains were selected for arsenic resistance, the ability to reduce arsenate to arsenite, and the ability to promote plant growth. P. vittata plants were cultivated for 4 months in a contaminated substrate consisting of arsenopyrite cinders and mature compost. Four different experimental conditions were tested: i non-inoculated plants; ii plants inoculated with the siderophore-producing and arsenate-reducing bacteria Pseudomonas sp. P1III2 and Delftia sp. P2III5 (A; iii plants inoculated with the siderophore and indoleacetic acid-producing bacteria Bacillus sp. MPV12, Variovorax sp. P4III4 and Pseudoxanthomonas sp. P4V6 (B, and iv plants inoculated with all five bacterial strains (AB. The presence of growth-promoting rhizobacteria increased plant biomass by up to 45% and increased As removal efficiency from 13% without bacteria to 35% in the presence of the mixed inoculum. Molecular analysis confirmed the persistence of the introduced bacterial strains in the soil and resulted in a significant impact on the structure of the bacterial community.

  12. Disruption of histone modification and CARM1 recruitment by arsenic represses transcription at glucocorticoid receptor-regulated promoters.

    Directory of Open Access Journals (Sweden)

    Fiona D Barr

    Full Text Available Chronic exposure to inorganic arsenic (iAs found in the environment is one of the most significant and widespread environmental health risks in the U.S. and throughout the world. It is associated with a broad range of health effects from cancer to diabetes as well as reproductive and developmental anomalies. This diversity of diseases can also result from disruption of metabolic and other cellular processes regulated by steroid hormone receptors via aberrant transcriptional regulation. Significantly, exposure to iAs inhibits steroid hormone-mediated gene activation. iAs exposure is associated with disease, but is also used therapeutically to treat specific cancers complicating an understanding of iAs action. Transcriptional activation by steroid hormone receptors is accompanied by changes in histone and non-histone protein post-translational modification (PTM that result from the enzymatic activity of coactivator and corepressor proteins such as GRIP1 and CARM1. This study addresses how iAs represses steroid receptor-regulated gene transcription. PTMs on histones H3 and H4 at the glucocorticoid receptor (GR-activated mouse mammary tumor virus (MMTV promoter were identified by chromatin immunoprecipitation analysis following exposure to steroid hormone+/-iAs. Histone H3K18 and H3R17 amino acid residues had significantly different patterns of PTMs after treatment with iAs. Promoter interaction of the coactivator CARM1 was disrupted, but the interaction of GRIP1, a p160 coactivator through which CARM1 interacts with a promoter, was intact. Over-expression of CARM1 was able to fully restore and GRIP1 partially restored iAs-repressed transcription indicating that these coactivators are functionally associated with iAs-mediated transcriptional repression. Both are essential for robust transcription at steroid hormone regulated genes and both are associated with disease when inappropriately expressed. We postulate that iAs effects on CARM1 and GRIP1

  13. Technology transfer: Promoting irrigation progress and best management practices

    Science.gov (United States)

    Educational efforts promoting irrigation best management practices are designed to increase adoption of these practices and increase public understanding of the importance of irrigation. They increase visibility and the impact of the Ogallala Aquifer Program and promote affiliated research and exten...

  14. 砷对儿童健康影响的研究进展%Progress in effects of arsenic on children's health

    Institute of Scientific and Technical Information of China (English)

    李惠

    2011-01-01

    砷对人类健康存在多方面的危害。由于儿童正处在快速的生长发育期,全身各个系统,尤其是神经系统极易受到环境中砷的危害,不仅增加各个系统相应疾病的发病率,而且会导致儿童认知能力降低,视知觉能力、注意力、语言和记忆力的损害。该文就近年来砷对儿童健康影响的文献进行综述,主要介绍了砷的研究背景、人体的暴露途径、体内的代谢、对儿童健康的危害及生物监测。%The health hazards of arsenic are various. Since children are in the period of rapid growth and development, nervous system is more vulnerable to the arsenic exposure in the environment. Not only does it increase the incidence of the corresponding disease in each system, but also results in neurotoxicological impairments including poor cognitive performance and disturbances in visual perception, psychomotor speed, attention, speech and memory. The progress in the field of effects of arsenic on children's health were reviewed in this article, it introduced the background of arsenic, human exposure pathways, metabolism of the human body,health hazards to children and biological monitoring.

  15. Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc, and copper. Comprehensive progress report, October 1, 1975--December 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, R. H.

    1978-10-01

    Investigations were undertaken to elucidate the mode of transepithelial transport of potentially toxic metal ions across the gastrointestinal tract, with primary attention given to cadmium, zinc, and arsenic. In addition, the toxic effects of cadmium on the metabolism of vitamin D and calcium have been investigated in some detail. Several approaches have been taken, including studies on the localization of heavy metals in the intestinal mucosa, the effects of cadmium on various parameters of calcium metabolism, the modes of intestinal absorption of cadmium, arsenate, and zinc, and the interactions of heavy metals with each other and with calcium, phosphorus, and vitamin D. Details of these experiments are attached in the Comprehensive Progress Report.

  16. 地下水砷污染研究进展%Research Progress of Arsenic Contamination in Groundwater

    Institute of Scientific and Technical Information of China (English)

    金阳; 姜月华; 李云

    2015-01-01

    Arsenic is a severely toxic substance resulting in cancer. Arsenic contamination of groundwater has had a sig-nificantly negative influence not only on human health, but also on ecological environment, and it has been a hot issue for a-broad and domestic scholars in recent years. This paper summarizes arsenic contamination in groundwater, introduces current status of the research focused on Arsenic in groundwater, meanwhile, it also simply depicts its source. In addition, this article shows several aspects of Arsenic contamination in details, including existence form, impact factors, and points out the instruc-tion for preventive control and remediation of arsenic contamination in groundwater.%砷是一种毒性很强的致癌物质,地下水的砷污染严重破坏生态环境,危害人类健康,已成为近年来国内外学者研究的热点问题。本文针对地下水的砷污染问题进行综述,介绍了地下水砷污染研究现状,并简单介绍了地下水中砷的来源。另外,还针对地下水中砷的存在形态及其影响因素等方面作了详细介绍,对砷污染的预防控制和修复治理起到指导作用。

  17. Research progress of arsenic removal technology by ferric salt%铁盐除砷技术研究进展

    Institute of Scientific and Technical Information of China (English)

    张志斌; 李锦祥; 边兴玉; 魏垒垒; 郭宁彬; 王志俊

    2012-01-01

    基于砷是一种自然界普遍存在的有毒元素,砷污染已成为一个亟待解决的全球性的环境问题.围绕低分子类铁盐、高分子类铁盐及其它铁类化合物三个方面综述了当前铁盐除砷技术的研究进展.结果表明:(1)铁盐除砷技术具有除砷效果好、经济、操作简单等优点;(2)研制高效、价成本、低能耗的除砷铁盐药剂以及多种药剂的联合使用将成为今后铁盐除砷技术的发展方向.%Arsenic is a prevalent toxic element in nature and the treatment of water with arsenic pollution has become a global environmental problem. The study introduces the technology of arsenic removal by ferric salt from the aspects of low molecular ferric salts, high molecular ferric salts and other iron species. The results show: (1) the technology of arsenic removal by feme salt has many advantages, such as higher removal efficiency, economy, simple operation and so on; (2)developing the ferric salts with high efficiency, low cost and low energy consumption and combined use of several chemicals will be the development direction of the technology of arsenic removal by ferric salt.

  18. Somatic LKB1 mutations promote cervical cancer progression.

    Directory of Open Access Journals (Sweden)

    Shana N Wingo

    Full Text Available Human Papilloma Virus (HPV is the etiologic agent for cervical cancer. Yet, infection with HPV is not sufficient to cause cervical cancer, because most infected women develop transient epithelial dysplasias that spontaneously regress. Progression to invasive cancer has been attributed to diverse host factors such as immune or hormonal status, as no recurrent genetic alterations have been identified in cervical cancers. Thus, the pressing question as to the biological basis of cervical cancer progression has remained unresolved, hampering the development of novel therapies and prognostic tests. Here we show that at least 20% of cervical cancers harbor somatically-acquired mutations in the LKB1 tumor suppressor. Approximately one-half of tumors with mutations harbored single nucleotide substitutions or microdeletions identifiable by exon sequencing, while the other half harbored larger monoallelic or biallelic deletions detectable by multiplex ligation probe amplification (MLPA. Biallelic mutations were identified in most cervical cancer cell lines; HeLa, the first human cell line, harbors a homozygous 25 kb deletion that occurred in vivo. LKB1 inactivation in primary tumors was associated with accelerated disease progression. Median survival was only 13 months for patients with LKB1-deficient tumors, but >100 months for patients with LKB1-wild type tumors (P = 0.015, log rank test; hazard ratio = 0.25, 95% CI = 0.083 to 0.77. LKB1 is thus a major cervical tumor suppressor, demonstrating that acquired genetic alterations drive progression of HPV-induced dysplasias to invasive, lethal cancers. Furthermore, LKB1 status can be exploited clinically to predict disease recurrence.

  19. Arsenic ototoxicity

    Institute of Scientific and Technical Information of China (English)

    Gulin Gokçen Kesici

    2016-01-01

    High levels of arsenic are found in many parts of the world and more than 100 million people may have been exposed to it. There is growing evidence to indicate that arsenic has a deleterious effect on the auditory system. This paper provides the general information of arsenic and its ototoxic effects.

  20. Does monitoring goal progress promote goal attainment? A meta-analysis of the experimental evidence.

    Science.gov (United States)

    Harkin, Benjamin; Webb, Thomas L; Chang, Betty P I; Prestwich, Andrew; Conner, Mark; Kellar, Ian; Benn, Yael; Sheeran, Paschal

    2016-02-01

    Control theory and other frameworks for understanding self-regulation suggest that monitoring goal progress is a crucial process that intervenes between setting and attaining a goal, and helps to ensure that goals are translated into action. However, the impact of progress monitoring interventions on rates of behavioral performance and goal attainment has yet to be quantified. A systematic literature search identified 138 studies (N = 19,951) that randomly allocated participants to an intervention designed to promote monitoring of goal progress versus a control condition. All studies reported the effects of the treatment on (a) the frequency of progress monitoring and (b) subsequent goal attainment. A random effects model revealed that, on average, interventions were successful at increasing the frequency of monitoring goal progress (d+ = 1.98, 95% CI [1.71, 2.24]) and promoted goal attainment (d+ = 0.40, 95% CI [0.32, 0.48]). Furthermore, changes in the frequency of progress monitoring mediated the effect of the interventions on goal attainment. Moderation tests revealed that progress monitoring had larger effects on goal attainment when the outcomes were reported or made public, and when the information was physically recorded. Taken together, the findings suggest that monitoring goal progress is an effective self-regulation strategy, and that interventions that increase the frequency of progress monitoring are likely to promote behavior change.

  1. Plan and Design Meticulously and Promoting Technical Progress

    Institute of Scientific and Technical Information of China (English)

    Miao Chengwu

    1994-01-01

    @@ Plan and design is the key link in captial construction, and the soul of engineering construction. China Petroleum Planning & Engineering Institute (CPPEI) is one of the main undertakers for planning and designing of petroleum industry,the only leading multi-functional institute with the first class design certificate. Now it has been an organization under the China National Petroleum Corporation(CNPC)for making development strategy planning, project evaluations and technical consulting, drawing up project development plan and providing technical recommendations. It can complete plan and design for the oil and gas field facilities, pipeline construction,petroleum relinery and petro-chemical industry engineering at home and abroad. It is also a center of servicing for new technical development and scientific research. Since CPPEI was established in 1978,it has meticulously conducted on planning and designing for the technical progress of petroleum engineering.

  2. Arsenic-mediated nephrotoxicity.

    Science.gov (United States)

    Robles-Osorio, Ma Ludivina; Sabath-Silva, Elizabeth; Sabath, Ernesto

    2015-05-01

    Chronic kidney disease (CKD) is an important global health problem that affects 8-15% of the population according to epidemiological studies done in different countries. Essential to prevention is the knowledge of the environmental factors associated with this disease, and heavy metals such as lead and cadmium are clearly associated with kidney injury and CKD progression. Arsenic is one of the most abundant contaminants in water and soil, and many epidemiological studies have found an association between arsenic and type 2 diabetes mellitus, hypertension and cancer; however, there is a scarcity of epidemiological studies about its association with kidney disease, and the evidence linking urinary arsenic excretion with CKD, higher urinary excretion of low molecular proteins, albuminuria or other markers of renal in injury is still limited, and more studies are necessary to characterize the role of arsenic on renal injury and CKD progression. Global efforts to reduce arsenic exposure remain important and research is also needed to determine whether specific therapies are beneficial in susceptible populations.

  3. Folic acid supplementation promotes mammary tumor progression in a rat model.

    Science.gov (United States)

    Deghan Manshadi, Shaidah; Ishiguro, Lisa; Sohn, Kyoung-Jin; Medline, Alan; Renlund, Richard; Croxford, Ruth; Kim, Young-In

    2014-01-01

    Folic acid supplementation may prevent the development of cancer in normal tissues but may promote the progression of established (pre)neoplastic lesions. However, whether or not folic acid supplementation can promote the progression of established (pre)neoplastic mammary lesions is unknown. This is a critically important issue because breast cancer patients and survivors in North America are likely exposed to high levels of folic acid owing to folic acid fortification and widespread supplemental use after cancer diagnosis. We investigated whether folic acid supplementation can promote the progression of established mammary tumors. Female Sprague-Dawley rats were placed on a control diet and mammary tumors were initiated with 7,12-dimethylbenza[a]anthracene at puberty. When the sentinel tumor reached a predefined size, rats were randomized to receive a diet containing the control, 2.5x, 4x, or 5x supplemental levels of folic acid for up to 12 weeks. The sentinel mammary tumor growth was monitored weekly. At necropsy, the sentinel and all other mammary tumors were analyzed histologically. The effect of folic acid supplementation on the expression of proteins involved in proliferation, apoptosis, and mammary tumorigenesis was determined in representative sentinel adenocarcinomas. Although no clear dose-response relationship was observed, folic acid supplementation significantly promoted the progression of the sentinel mammary tumors and was associated with significantly higher sentinel mammary tumor weight and volume compared with the control diet. Furthermore, folic acid supplementation was associated with significantly higher weight and volume of all mammary tumors. The most significant and consistent mammary tumor-promoting effect was observed with the 2.5x supplemental level of folic acid. Folic acid supplementation was also associated with an increased expression of BAX, PARP, and HER2. Our data suggest that folic acid supplementation may promote the progression

  4. Association Study between Promoter Polymorphism of TPH1 and Progression of Idiopathic Scoliosis

    OpenAIRE

    Vasil Yablanski; Svetla Nikolova; Evgeni Vlaev; Alexey Savov; Ivo Kremensky

    2016-01-01

    The concept of disease-modifier genes as an element of genetic heterogeneity has been widely accepted and reported. The aim of the current study is to investigate the association between the promoter polymorphism TPH1 (rs10488682) and progression of idiopathic scoliosis (IS) in Eastern European population sample. A total of 105 patients and 210 healthy gender-matched controls were enrolled in this study. The TPH1 promoter polymorphism was genotyped by amplification followed by restriction. Th...

  5. Arsenic poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Schoolmeester, W.L.; White, D.R.

    1980-02-01

    Arsenic poisoning continues to require awareness of its diverse clinical manifestations. Industry is the major source of arsenic exposure. Although epidemiologic studies strongly contend that arsenic is carcinogenic, there are little supportive research data. Arsenic poisoning, both acute and chronic, is often overlooked initially in the evaluation of the patient with multisystem disease, but once it is suspected, many accurate methods are available to quantitate the amount and duration of exposure. Treatment with dimercaprol remains the mainstay of therapy, and early treatment is necessary to prevent irreversible complications.

  6. Adverse effect of the CCR5 promoter -2459A allele on HIV-1 disease progression

    DEFF Research Database (Denmark)

    Knudsen, T B; Kristiansen, T B; Katzenstein, T L;

    2001-01-01

    HIV positive individuals heterozygous for a 32 basepair deletion in the CCR5 encoding gene (CCR5 Delta32) have a reduced number of CCR5 receptors on the cell surface and a slower progression towards AIDS and death. Other human polymorphisms, such as the CCR2 64I and the CCR5 promoter -2459 A...

  7. The Shh receptor Boc promotes progression of early medulloblastoma to advanced tumors.

    Science.gov (United States)

    Mille, Frédéric; Tamayo-Orrego, Lukas; Lévesque, Martin; Remke, Marc; Korshunov, Andrey; Cardin, Julie; Bouchard, Nicolas; Izzi, Luisa; Kool, Marcel; Northcott, Paul A; Taylor, Michael D; Pfister, Stefan M; Charron, Frédéric

    2014-10-13

    During cerebellar development, Sonic hedgehog (Shh) signaling drives the proliferation of granule cell precursors (GCPs). Aberrant activation of Shh signaling causes overproliferation of GCPs, leading to medulloblastoma. Although the Shh-binding protein Boc associates with the Shh receptor Ptch1 to mediate Shh signaling, whether Boc plays a role in medulloblastoma is unknown. Here, we show that BOC is upregulated in medulloblastomas and induces GCP proliferation. Conversely, Boc inactivation reduces proliferation and progression of early medulloblastomas to advanced tumors. Mechanistically, we find that Boc, through elevated Shh signaling, promotes high levels of DNA damage, an effect mediated by CyclinD1. High DNA damage in the presence of Boc increases the incidence of Ptch1 loss of heterozygosity, an important event in the progression from early to advanced medulloblastoma. Together, our results indicate that DNA damage promoted by Boc leads to the demise of its own coreceptor, Ptch1, and consequently medulloblastoma progression.

  8. Arsenic sulfide promotes apoptosis in retinoid acid resistant human acute promyelocytic leukemic NB4-R1 cells through downregulation of SET protein.

    Directory of Open Access Journals (Sweden)

    Yuwang Tian

    Full Text Available Tetra-arsenic tetra-sulfide (As4S4 is an arsenic compound with anti-tumor activity, especially in acute promyelocytic leukemia (APL that are resistant to retinoic acid (RA. Although recent studies revealed that the therapeutic action of As4S4 is closely associated with the induction of cellular apoptosis, the exact molecular mechanism of action of As4S4 in RA-resistant APL remains to be clarified. In this study, we found that As4S4-induced apoptosis was accompanied by reduced mRNA and protein expression of SET gene in RA-resistant NB4-R1 cells. Moreover, RNAi knockdown of SET gene further promoted As4S4-induced apoptosis, while SET over-expression inhibited it, suggesting that As4S4 induces apoptosis through the reduction of SET protein in NB4-R1 cells. We also demonstrated that the knockdown of SET gene resulted in the upregulation of protein phosphatase 2 (PP2A expression and the downregulation of promyelocytic leukemia and retinoic acid receptor α fusion gene (PML-RARα expression, which were enhanced by As4S4 treatments. By contrast, over-expression of SET gene resulted in PP2A downregulation and PML-RARα upregulation, which were abolished by As4S4 pretreatment. Since PP2A is a pro-apoptotic factor and PMLRARα is an anti-apoptotic factor, our results suggest that As4S4-induced apoptosis in NB4-R1 cells is through the downregulation of SET protein expression, which in turn increases PP2A and reduces PML-RARα expressions to lead to cell apoptosis.

  9. Hmga2 functions as a competing endogenous RNA to promote lung cancer progression

    Science.gov (United States)

    Kumar, Madhu S.; Armenteros-Monterroso, Elena; East, Philip; Chakravorty, Probir; Matthews, Nik; Winslow, Monte M.; Downward, Julian

    2013-01-01

    Non-small cell lung cancer (NSCLC) is the most prevalent histological cancer subtype worldwide1. As the majority of patients present with invasive, metastatic disease2, it is vital to understand the basis for lung cancer progression. Hmga2 is highly expressed in metastatic lung adenocarcinoma where it contributes to cancer progression and metastasis3-6. Here we show that Hmga2 promotes lung cancer progression by operating as a competing endogenous RNA (ceRNA)7-11 for the let-7 microRNA (miRNA) family. Hmga2 can promote the transformation of lung cancer cells independent of protein-coding function but dependent upon the presence of let-7 sites; this occurs without changes in the levels of let-7 isoforms, suggesting that Hmga2 affects let-7 activity by altering miRNA targeting. These effects are further observed in vivo, where Hmga2 ceRNA activity drives lung cancer growth, invasion and dissemination. Integrated analysis of miRNA target prediction algorithms and metastatic lung cancer gene expression data reveals the TGF-β co-receptor Tgfbr312 as a putative target of Hmga2 ceRNA function. Tgfbr3 expression is regulated by the Hmga2 ceRNA via differential recruitment to Argonaute-2 (Ago2), and TGF-β signalling driven by Tgfbr3 is largely necessary for Hmga2 to promote lung cancer progression. Finally, analysis of NSCLC patient gene expression data reveals that HMGA2 and TGFBR3 are co-ordinately regulated in NSCLC patient material, a vital corollary to ceRNA function. Taken together, these results suggest that Hmga2 promotes lung carcinogenesis as both a protein-coding gene and a non-coding RNA; such dual-function regulation of gene expression networks reflects a novel means by which oncogenes promote disease progression. PMID:24305048

  10. Arsenic poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Low, D.G.

    1971-01-01

    The use of arsenic in ant poisons, herbicides, and insecticides affords the necessary contact with the poison by pets. Treatment was discussed in relation to two circumstances: very early poisoning in which the owner has observed ingestion of the arsenic, and when the signs of the poisoning are evident. Treatment for early ingestion involves emptying the stomach before the arsenic can pass in quantity into the intestine. This is followed with a 1% solution of sodium bicarbonate, with the administering of 3 to 6 mg of apomorphine. When signs of arsenic toxicity are already advanced, there is little advantage to be gained by either gastric lavage or administration of an emetic. The treatment then consists of the intramuscular administration of dimercaprol (BAL) at a dosage of 3 mg/lb of body weight three times a day until recovery. This is the specific antidote for arsenic. 1 reference.

  11. Biochar in co-contaminated soil manipulates arsenic solubility and microbiological community structure, and promotes organochlorine degradation.

    Science.gov (United States)

    Gregory, Samuel J; Anderson, Christopher W N; Camps-Arbestain, Marta; Biggs, Patrick J; Ganley, Austen R D; O'Sullivan, Justin M; McManus, Michael T

    2015-01-01

    We examined the effect of biochar on the water-soluble arsenic (As) concentration and the extent of organochlorine degradation in a co-contaminated historic sheep-dip soil during a 180-d glasshouse incubation experiment. Soil microbial activity, bacterial community and structure diversity were also investigated. Biochar made from willow feedstock (Salix sp) was pyrolysed at 350 or 550°C and added to soil at rates of 10 g kg-1 and 20 g kg-1 (representing 30 t ha-1 and 60 t ha-1). The isomers of hexachlorocyclohexane (HCH) alpha-HCH and gamma-HCH (lindane), underwent 10-fold and 4-fold reductions in concentration as a function of biochar treatment. Biochar also resulted in a significant reduction in soil DDT levels (P activity was significantly increased (P microbiological activity (dehydrogenase activity) due to biochar amendment was responsible for enhanced degradation of organochlorines in the soil. Biochar therefore partially overcame the co-contaminant effect of As, allowing for enhanced natural attenuation of organochlorines in soil.

  12. Enhanced carcinogenicity by coexposure to arsenic and iron and a novel remediation system for the elements in well drinking water.

    Science.gov (United States)

    Kumasaka, Mayuko Y; Yamanoshita, Osamu; Shimizu, Shingo; Ohnuma, Shoko; Furuta, Akio; Yajima, Ichiro; Nizam, Saika; Khalequzzaman, Md; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

    2013-03-01

    Various carcinomas including skin cancer are explosively increasing in arsenicosis patients who drink arsenic-polluted well water, especially in Bangladesh. Although well drinking water in the cancer-prone areas contains various elements, very little is known about the effects of elements except arsenic on carcinogenicity. In order to clarify the carcinogenic effects of coexposure to arsenic and iron, anchorage-independent growth and invasion in human untransformed HaCaT and transformed A431 keratinocytes were examined. Since the mean ratio of arsenic and iron in well water was 1:10 in cancer-prone areas of Bangladesh, effects of 1 μM arsenic and 10 μM iron were investigated. Iron synergistically promoted arsenic-mediated anchorage-independent growth in untransformed and transformed keratinocytes. Iron additionally increased invasion in both types of keratinocytes. Activities of c-SRC and ERK that regulate anchorage-independent growth and invasion were synergistically enhanced in both types of keratinocytes. Our results suggest that iron promotes arsenic-mediated transformation of untransformed keratinocytes and progression of transformed keratinocytes. We then developed a low-cost and high-performance adsorbent composed of a hydrotalcite-like compound for arsenic and iron. The adsorbent rapidly reduced concentrations of both elements from well drinking water in cancer-prone areas of Bangladesh to levels less than those in WHO health-based guidelines for drinking water. Thus, we not only demonstrated for the first time increased carcinogenicity by coexposure to arsenic and iron but also proposed a novel remediation system for well drinking water.

  13. [Effects of organic fertilization on arsenic absorption of pakchoi (Brassica chinensis) on arsenic-contaminated red soil].

    Science.gov (United States)

    Li, Lian-Fang; Geng, Zhi-Xi; Zeng, Xi-Bai; Bai, Ling-Yu; Su, Shi-Ming

    2011-01-01

    A pot experiment with arsenic-contaminated red soil was conducted to study the effects of applying pig dung and chicken manure on the growth and arsenic absorption of pakchoi (Brassica chinensis), and on soil available arsenic. Applying pig dung and chicken manure to the arsenic-contaminated red soil increased the biomass of pakchoi to some extent. Comparing with the control, applying pig dung increased the pakchoi biomass significantly (P Organic fertilization promoted the arsenic absorption of pakchoi, with the arsenic uptake after applying pig dung increased by 20.7%-53.9%. The application of pig dung and chicken manure to arsenic-contaminated red soil could somewhat increase the soil available arsenic content and the arsenic uptake by crops, and thus, increase the risks of agricultural product quality and environment.

  14. Arsenic trioxide promotes mitochondrial DNA mutation and cell apoptosis in primary APL cells and NB4 cell lines

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    This study aimed to investigate the effects of arsenic trioxide(As2O3) on the mitochondrial DNA(mtDNA) of acute promyelocytic leukemia(APL) cells.The NB4 cell line was treated with 2.0 μmol/L As2O3 in vitro,and the primary APL cells were treated with 2.0 μmol/L As2O3 in vitro and 0.16 mg kg-1 d-1 As2O3 in vivo.The mitochondrial DNA of all the cells above was amplified by PCR,directly sequenced and analyzed by Sequence Navigatore and Factura software.The apoptosis rates were assayed by flow cytometry.Mitochondrial DNA mutation in the D-loop region was found in NB4 and APL cells before As2O3 use,but the mutation spots were remarkably increased after As2O3 treatment,which was positively correlated to the rates of cellular apoptosis,the correlation coefficient:rNB4-As2O3=0.973818,and rAPL-As2O3=0.934703.The mutation types include transition,transversion,codon insertion or deletion,and the mutation spots in all samples were not constant and regular.It is revealed that As2O3 aggravates mtDNA mutation in the D-loop region of acute promyelocytic leukemia cells both in vitro and in vivo.Mitochondrial DNA might be one of the targets of As2O3 in APL treatment.

  15. Biochar in co-contaminated soil manipulates arsenic solubility and microbiological community structure, and promotes organochlorine degradation.

    Directory of Open Access Journals (Sweden)

    Samuel J Gregory

    Full Text Available We examined the effect of biochar on the water-soluble arsenic (As concentration and the extent of organochlorine degradation in a co-contaminated historic sheep-dip soil during a 180-d glasshouse incubation experiment. Soil microbial activity, bacterial community and structure diversity were also investigated. Biochar made from willow feedstock (Salix sp was pyrolysed at 350 or 550°C and added to soil at rates of 10 g kg-1 and 20 g kg-1 (representing 30 t ha-1 and 60 t ha-1. The isomers of hexachlorocyclohexane (HCH alpha-HCH and gamma-HCH (lindane, underwent 10-fold and 4-fold reductions in concentration as a function of biochar treatment. Biochar also resulted in a significant reduction in soil DDT levels (P < 0.01, and increased the DDE:DDT ratio. Soil microbial activity was significantly increased (P < 0.01 under all biochar treatments after 60 days of treatment compared to the control. 16S amplicon sequencing revealed that biochar-amended soil contained more members of the Chryseobacterium, Flavobacterium, Dyadobacter and Pseudomonadaceae which are known bioremediators of hydrocarbons. We hypothesise that a recorded short-term reduction in the soluble As concentration due to biochar amendment allowed native soil microbial communities to overcome As-related stress. We propose that increased microbiological activity (dehydrogenase activity due to biochar amendment was responsible for enhanced degradation of organochlorines in the soil. Biochar therefore partially overcame the co-contaminant effect of As, allowing for enhanced natural attenuation of organochlorines in soil.

  16. Proinflammatory Cytokines in Prostate Cancer Development and Progression Promoted by High-Fat Diet

    Directory of Open Access Journals (Sweden)

    Hua Xu

    2015-01-01

    Full Text Available Background. We aimed to examine whether proinflammatory cytokines participated in prostate cancer (PCa development and progression promoted by high-fat diet (HFD. Methods. TRAMP (transgenic adenocarcinoma mouse prostate mice were randomly divided into two groups: normal diet group and HFD group. Mortality rate and tumor formation rate were examined. TRAMP mice were sacrificed and sampled on the 20th, 24th, and 28th week, respectively. Levels of proinflammatory cytokines, including IL-1α, IL-1β, IL-6, and TNF-α, were tested by FlowCytomix. Prostate tissue of TRAMP mice was used for histology study. Results. A total of 13 deaths of TRAMP mice were observed, among which 3 (8.33% were from the normal diet group and 10 (27.78% from the HFD group. The mortality rate of TRAMP mice from HFD group was significantly higher than that of normal diet group (P=0.032. Tumor formation rate at 20th week of age of HFD group was significantly higher than that of normal diet group (P=0.045. Proinflammatory cytokines levels, including IL-1α, IL-1β, IL-6, and TNF-α, were significantly higher in HFD TRAMP mice. Conclusions. HFD could promote TRAMP mouse PCa development and progression with elevated proinflammatory cytokines levels. Proinflammatory cytokines could contribute to PCa development and progression promoted by HFD.

  17. Mutant p53 promotes tumor progression and metastasis by the endoplasmic reticulum UDPase ENTPD5.

    Science.gov (United States)

    Vogiatzi, Fotini; Brandt, Dominique T; Schneikert, Jean; Fuchs, Jeannette; Grikscheit, Katharina; Wanzel, Michael; Pavlakis, Evangelos; Charles, Joël P; Timofeev, Oleg; Nist, Andrea; Mernberger, Marco; Kantelhardt, Eva J; Siebolts, Udo; Bartel, Frank; Jacob, Ralf; Rath, Ariane; Moll, Roland; Grosse, Robert; Stiewe, Thorsten

    2016-12-27

    Mutations in the p53 tumor suppressor gene are the most frequent genetic alteration in cancer and are often associated with progression from benign to invasive stages with metastatic potential. Mutations inactivate tumor suppression by p53, and some endow the protein with novel gain of function (GOF) properties that actively promote tumor progression and metastasis. By comparative gene expression profiling of p53-mutated and p53-depleted cancer cells, we identified ectonucleoside triphosphate diphosphohydrolase 5 (ENTPD5) as a mutant p53 target gene, which functions as a uridine 5'-diphosphatase (UDPase) in the endoplasmic reticulum (ER) to promote the folding of N-glycosylated membrane proteins. A comprehensive pan-cancer analysis revealed a highly significant correlation between p53 GOF mutations and ENTPD5 expression. Mechanistically, mutp53 is recruited by Sp1 to the ENTPD5 core promoter to induce its expression. We show ENTPD5 to be a mediator of mutant p53 GOF activity in clonogenic growth, architectural tissue remodeling, migration, invasion, and lung colonization in an experimental metastasis mouse model. Our study reveals folding of N-glycosylated membrane proteins in the ER as a mechanism underlying the metastatic progression of tumors with mutp53 that could provide new possibilities for cancer treatment.

  18. Promoter hypermethylation-mediated inactivation of multiple Slit-Robo pathway genes in cervical cancer progression

    Directory of Open Access Journals (Sweden)

    Mansukhani Mahesh

    2006-05-01

    Full Text Available Abstract Background Cervical Cancer (CC exhibits highly complex genomic alterations. These include hemizygous deletions at 4p15.3, 10q24, 5q35, 3p12.3, and 11q24, the chromosomal sites of Slit-Robo pathway genes. However, no candidate tumor suppressor genes at these regions have been identified so far. Slit family of secreted proteins modulates chemokine-induced cell migration of distinct somatic cell types. Slit genes mediate their effect by binding to its receptor Roundabout (Robo. These genes have shown to be inactivated by promoter hypermethylation in a number of human cancers. Results To test whether Slit-Robo pathway genes are targets of inactivation at these sites of deletion, we examined promoter hypermethylation of SLIT1, SLIT2, SLIT3, ROBO1, and ROBO3 genes in invasive CC and its precursor lesions. We identified a high frequency of promoter hypermethylation in all the Slit-Robo genes resulting in down regulated gene expression in invasive CC, but the inhibitors of DNA methylation and histone deacetylases (HDACs in CC cell lines failed to effectively reactivate the down-regulated expression. These results suggest a complex mechanism of inactivation in the Slit-Robo pathway in CC. By analysis of cervical precancerous lesions, we further show that promoter hypermethylation of Slit-Robo pathway occurs early in tumor progression. Conclusion Taken together, these findings suggest that epigenetic alterations of Slit-Robo pathway genes (i play a role in CC development, (ii further delineation of molecular basis of promoter methylation-mediated gene regulation provides a potential basis for epigenetic-based therapy in advanced stage CC, and (iii form epigenetic signatures to identify precancerous lesions at risk to progression.

  19. Association Study between Promoter Polymorphism of TPH1 and Progression of Idiopathic Scoliosis.

    Science.gov (United States)

    Yablanski, Vasil; Nikolova, Svetla; Vlaev, Evgeni; Savov, Alexey; Kremensky, Ivo

    2016-01-01

    The concept of disease-modifier genes as an element of genetic heterogeneity has been widely accepted and reported. The aim of the current study is to investigate the association between the promoter polymorphism TPH1 (rs10488682) and progression of idiopathic scoliosis (IS) in Eastern European population sample. A total of 105 patients and 210 healthy gender-matched controls were enrolled in this study. The TPH1 promoter polymorphism was genotyped by amplification followed by restriction. The statistical analysis was performed by Fisher's Exact Test. The results indicated that the genotypes and alleles of TPH1 (rs10488682) are not correlated with curve severity, curve pattern, or bracing. Therefore, the examined polymorphic variant could not be considered as a genetic factor with modifying effect of IS. In conclusion, this case-control study revealed no statistically significant association between TPH1 (rs10488682) and progression of IS in Eastern European population sample. These preliminary results should be replicated in extended population studies including larger sample sizes. The identification of molecular markers for IS could be useful for a more accurate prognosis of the risk for a rapid progression of the curve. That would permit early stage treatment of the patient with the least invasive procedures.

  20. Neural Cell Adhesion Protein CNTN1 Promotes the Metastatic Progression of Prostate Cancer.

    Science.gov (United States)

    Yan, Judy; Ojo, Diane; Kapoor, Anil; Lin, Xiaozeng; Pinthus, Jehonathan H; Aziz, Tariq; Bismar, Tarek A; Wei, Fengxiang; Wong, Nicholas; De Melo, Jason; Cutz, Jean-Claude; Major, Pierre; Wood, Geoffrey; Peng, Hao; Tang, Damu

    2016-03-15

    Prostate cancer metastasis is the main cause of disease-related mortality. Elucidating the mechanisms underlying prostate cancer metastasis is critical for effective therapeutic intervention. In this study, we performed gene-expression profiling of prostate cancer stem-like cells (PCSC) derived from DU145 human prostate cancer cells to identify factors involved in metastatic progression. Our studies revealed contactin 1 (CNTN1), a neural cell adhesion protein, to be a prostate cancer-promoting factor. CNTN1 knockdown reduced PCSC-mediated tumor initiation, whereas CNTN1 overexpression enhanced prostate cancer cell invasion in vitro and promoted xenograft tumor formation and lung metastasis in vivo. In addition, CNTN1 overexpression in DU145 cells and corresponding xenograft tumors resulted in elevated AKT activation and reduced E-cadherin (CDH1) expression. CNTN1 expression was not readily detected in normal prostate glands, but was clearly evident on prostate cancer cells in primary tumors and lymph node and bone metastases. Tumors from 637 patients expressing CNTN1 were associated with prostate cancer progression and worse biochemical recurrence-free survival following radical prostatectomy (P prostate cancer progression and metastasis, prompting further investigation into the mechanisms that enable neural proteins to become aberrantly expressed in non-neural malignancies.

  1. PIAS1-FAK Interaction Promotes the Survival and Progression of Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Jerfiz D. Constanzo

    2016-05-01

    Full Text Available The sequence of genomic alterations acquired by cancer cells during tumor progression and metastasis is poorly understood. Focal adhesion kinase (FAK is a non-receptor tyrosine kinase that integrates cytoskeleton remodeling, mitogenic signaling and cell survival. FAK has previously been reported to undergo nuclear localization during cell migration, cell differentiation and apoptosis. However, the mechanism behind FAK nuclear accumulation and its contribution to tumor progression has remained elusive. We report that amplification of FAK and the SUMO E3 ligase PIAS1 gene loci frequently co-occur in non-small cell lung cancer (NSCLC cells, and that both gene products are enriched in a subset of primary NSCLCs. We demonstrate that endogenous FAK and PIAS1 proteins interact in the cytoplasm and the cell nucleus of NSCLC cells. Ectopic expression of PIAS1 promotes proteolytic cleavage of the FAK C-terminus, focal adhesion maturation and FAK nuclear localization. Silencing of PIAS1 deregulates focal adhesion turnover, increases susceptibility to apoptosis in vitro and impairs tumor xenograft formation in vivo. Nuclear FAK in turn stimulates gene transcription favoring DNA repair, cell metabolism and cytoskeleton regulation. Consistently, ablation of FAK by CRISPR/Cas9 editing, results in basal DNA damage, susceptibility to ionizing radiation and impaired oxidative phosphorylation. Our findings provide insight into a mechanism regulating FAK cytoplasm-nuclear distribution and demonstrate that FAK activity in the nucleus promotes NSCLC survival and progression by increasing cell-ECM interaction and DNA repair regulation.

  2. Association Study between Promoter Polymorphism of TPH1 and Progression of Idiopathic Scoliosis

    Directory of Open Access Journals (Sweden)

    Vasil Yablanski

    2016-01-01

    Full Text Available The concept of disease-modifier genes as an element of genetic heterogeneity has been widely accepted and reported. The aim of the current study is to investigate the association between the promoter polymorphism TPH1 (rs10488682 and progression of idiopathic scoliosis (IS in Eastern European population sample. A total of 105 patients and 210 healthy gender-matched controls were enrolled in this study. The TPH1 promoter polymorphism was genotyped by amplification followed by restriction. The statistical analysis was performed by Fisher’s Exact Test. The results indicated that the genotypes and alleles of TPH1 (rs10488682 are not correlated with curve severity, curve pattern, or bracing. Therefore, the examined polymorphic variant could not be considered as a genetic factor with modifying effect of IS. In conclusion, this case-control study revealed no statistically significant association between TPH1 (rs10488682 and progression of IS in Eastern European population sample. These preliminary results should be replicated in extended population studies including larger sample sizes. The identification of molecular markers for IS could be useful for a more accurate prognosis of the risk for a rapid progression of the curve. That would permit early stage treatment of the patient with the least invasive procedures.

  3. Arsenic transformation and plant growth promotion characteristics of As-resistant endophytic bacteria from As-hyperaccumulator Pteris vittata.

    Science.gov (United States)

    Xu, Jia-Yi; Han, Yong-He; Chen, Yanshan; Zhu, Ling-Jia; Ma, Lena Q

    2016-02-01

    The ability of As-resistant endophytic bacteria in As transformation and plant growth promotion was determined. The endophytes were isolated from As-hyperaccumulator Pteris vittata (PV) after growing for 60 d in a soil containing 200 mg kg(-1) arsenate (AsV). They were isolated in presence of 10 mM AsV from PV roots, stems, and leaflets, representing 4 phyla and 17 genera. All endophytes showed at least one plant growth promoting characteristics including IAA synthesis, siderophore production and P solubilization. The root endophytes had higher P solubilization ability than the leaflet (60.0 vs. 18.3 mg L(-1)). In presence of 10 mM AsV, 6 endophytes had greater growth than the control, suggesting As-stimulated growth. Furthermore, root endophytes were more resistant to AsV while the leaflet endophytes were more tolerant to arsenite (AsIII), which corresponded to the dominant As species in PV tissues. Bacterial As resistance was positively correlated to their ability in AsV reduction but not AsIII oxidation. The roles of those endophytes in promoting plant growth and As resistance in P. vittata warrant further investigation.

  4. Arsenic poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Low, D.G.

    1974-01-01

    The use of arsenic in ant poisons, herbicides, and insecticides affords the necessary contact with the poison by pets. The gastrointestinal tract appears to suffer the greatest though there may also be injury to the liver and kidneys. The treatments discussed were in relation to very early poisoning in which the owner had observed ingestion of the arsenic, and when the signs of the poisoning were evident. Early observation treatment included emptying the stomach before the arsenic passed in quantity into the intestine. If the signs of toxicity were already advanced, then the treatment consisted of the intramuscular administration of dimercaprol (BAL) at a dosage of 3 mg/lb of body weight three times a day until recovery. l reference.

  5. Arsenic poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Furr, A.

    1977-01-01

    The route of arsenic exposure is usually by ingestion, thus the veterinarian is concerned with treating either an acute or a peracute condition. The arsenic compounds are considered to be highly toxic with a rapid onset of clinical signs. The toxicity and rapidity of onset are variable, depending upon the age and the species of animal. The chemical form and solubility of the toxicant also play a role in the course of the clinical syndrome. Inorganic arsenicals inhibit the sulfhydryl enzyme systems which are essential for normal cellular respiration and for metabolism of fats and carbohydrates. Therapeutic measures are intended to either remove or inactivate the unabsorbed material in the intestine, protect the alimentary tract, reverse the toxic syndrome and restore the homeostatic equilibrium of the animal. 5 references.

  6. Bcl-2 promotes malignant progression in a PDGF-B-dependent murine model of oligodendroglioma.

    Science.gov (United States)

    Doucette, Tiffany; Yang, Yuhui; Zhang, Wei; Fuller, Gregory N; Suki, Dima; Fults, Daniel W; Rao, Ganesh

    2011-11-01

    A significant subset of gliomas arises after activation of the proproliferative platelet-derived growth factor (PDGF) pathway. The progression of low-grade gliomas to more malignant tumors may be due to oncogenic cellular programs combining with those suppressing apoptosis. Antiapoptotic genes are overexpressed in a variety of cancers, and the antiapoptotic gene, BCL2, is associated with treatment resistance and tumor recurrence in gliomas. However, the impact of antiapoptotic gene expression to tumor formation and progression is unclear. We overexpressed Bcl-2 in a PDGFB-dependent mouse model of oligodendroglioma, a common glioma subtype, to assess its effect in vivo. We hypothesized that the antiapoptotic effect would complement the proproliferative effect of PDGFB to promote tumor formation and progression to anaplastic oligodendroglioma (AO). Here, we show that coexpression of PDGFB and Bcl-2 results in a higher overall tumor formation rate compared to PDGFB alone. Coexpression of PDGFB and Bcl-2 promotes progression to AO with prominent foci of necrosis, a feature of high-grade gliomas. Median tumor latency was shorter in mice injected with PDGFB and Bcl-2 compared to those injected with PDGFB alone. Although independent expression of Bcl-2 was insufficient to induce tumors, suppression of apoptosis (detected by cleaved caspase-3 expression) was more pronounced in AOs induced by PDGFB and Bcl-2 compared to those induced by PDGFB alone. Tumor cell proliferation (detected by phosphohistone H3 activity) was also more robust in high-grade tumors induced by PDGFB and Bcl-2. Our results indicate that suppressed apoptosis enhances oligodendroglioma formation and engenders a more malignant phenotype.

  7. CD147 reinforces [Ca2+]i oscillations and promotes oncogenic progression in hepatocellular carcinoma.

    Science.gov (United States)

    Tang, Juan; Guo, Yun-Shan; Yu, Xiao-Ling; Huang, Wan; Zheng, Ming; Zhou, Ying-Hui; Nan, Gang; Wang, Jian-Chao; Yang, Hai-Jiao; Yu, Jing-Min; Jiang, Jian-Li; Chen, Zhi-Nan

    2015-10-27

    Oscillations in intracellular Ca2+ concentrations ([Ca2+]i) mediate various cellular function. Although it is known that [Ca2+]i oscillations are susceptible to dysregulation in tumors, the tumor-specific regulators of [Ca2+]i oscillations are poorly characterized. We discovered that CD147 promotes hepatocellular carcinoma (HCC) metastasis and proliferation by enhancing the amplitude and frequency of [Ca2+]i oscillations in HCC cells. CD147 activates two distinct signaling pathways to regulate [Ca2+]i oscillations. By activating FAK-Src-IP3R1 signaling pathway, CD147 promotes Ca2+ release from endoplasmic reticulum (ER) and enhances the amplitude of [Ca2+]i oscillations. Furthermore, CD147 accelerates ER Ca2+refilling and enhances the frequency of [Ca2+]i oscillations through activating CaMKP-PAK1-PP2A-PLB-SERCA signaling pathway. Besides, CD147-promoted ER Ca2+ release and refilling are tightly regulated by changing [Ca2+]i. CD147 may activate IP3R1 channel under low [Ca2+]i conditions and CD147 may activate SERCA pump under high [Ca2+]i conditions. CD147 deletion suppresses HCC tumorigenesis and increases the survival rate of liver-specific CD147 knockout mice by regulating [Ca2+]i oscillations in vivo. Together, these results reveal that CD147 functions as a critical regulator of ER-dependent [Ca2+]i oscillations to promote oncogenic progression in HCC.

  8. CAV1 promotes HCC cell progression and metastasis through Wnt/β-catenin pathway.

    Directory of Open Access Journals (Sweden)

    Hongxiu Yu

    Full Text Available Caveolin-1 (CAV1 has significant roles in many primary tumors and metastasis, despite the fact that malignant cells from different cancer types have different profiles of CAV1 expression. There is little information concerning CAV1 expression and role in hepatocellular carcinoma (HCC progresion and metastasis. The role of CAV1 in HCC progression was explored in this study. We reported that CAV1 was overexpressed in highly invasive HCC cell lines compared with poorly invasive ones. The immunohistochemical staining was obviously stronger in metastatic HCC samples than in the non-metastatic specimens via tissue microarrays. Furthermore, CAV1 overexpression enhanced HCC cell invasiveness in vitro, and promoted tumorigenicity and lung metastasis in vivo. By contrast, CAV1 stable knockdown markedly reduced these malignant behaviors. Importantly, we found that CAV1 could induce EMT process through Wnt/β-catenin pathway to promote HCC metastasis. We also identify MMP-7 as a novel downstream target of CAV1. We have determined that CAV1 acts as a mediator between hyperactive ERK1/2 signaling and regulation of MMP-7 transcription. Together, these studies mechanistically show a previously unrecognized interplay between CAV1, EMT, ERK1/2 and MMP-7 that is likely significant in the progression of HCC toward metastasis.

  9. Nuclear localization of TEF3-1 promotes cell cycle progression and angiogenesis in cancer.

    Science.gov (United States)

    Teng, Kaixuan; Deng, Cuilan; Xu, Jie; Men, Qiuxu; Lei, Tao; Di, Da; Liu, Ting; Li, Wenhua; Liu, Xin

    2016-03-22

    TEF3-1 (transcriptional enhancer factor 3 isoform 1), also known as TEAD4 (TEA domain family member 4), was recently revealed as an oncogenic character in cancer development. However, the underlying molecular pathogenic mechanisms remain undefined. In this paper, we investigated nuclear TEF3-1 could promote G1/S transition in HUVECs, and the expression levels of cyclins and CDKs were upregulated. Additionally, if TEF3-1 was knocked down, the expression of cyclins and CDKs was downregulated while the expression of P21, a negative regulator of the cell cycle, was upregulated. A microarray analysis also confirmed that TEF3-1 overexpression upregulates genes that are related to cell cycle progression and the promotion of angiogenesis. Moreover, we observed that nuclear TEF3-1 was highly expressed during the formation of vascular structures in gastric cancer (GC). Finally, tumor xenograft experiments indicated that, when TEF3-1 was knocked down, tumor growth and angiogenesis were also suppressed. Taken together, these results demonstrate for the first time that TEF3-1 localization to the nucleus stimulates the cell cycle progression in HUVECs and specifically contributes to tumor angiogenesis. Nuclear TEF3-1 in HUVECs may serve as an oncogenic biomarker, and the suppression of TEF3-1 may be a potential target in anti-tumor therapy.

  10. Arsenic in Food

    Science.gov (United States)

    ... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Food Home Food Foodborne Illness & Contaminants Metals Arsenic Share ... of the Method used to Measure Arsenic in Foods Inductively Coupled Plasma-Mass Spectrometric Determination of Arsenic, ...

  11. Research Progress on Treatment of Arsenic-Containing Drinking Water by Oxidation Methods%氧化法处理含砷饮用水的研究进展

    Institute of Scientific and Technical Information of China (English)

    周文庆; 冯燕; 朱友利; 邴帅; 齐欣

    2012-01-01

    According to the presence form,physicochemical property and toxicity of arsenic in drinking water, the several conventional treatment methods of arsenic-containing drinking water and their principles,advantages and disadvantages are briefly introduced in the paper. The principles and research progress on As( III )removal by oxidation methods from drinking water are emphasisly summarized,and the prospect of application of arsenic-containing treatment by oxidation methods from drinking water is put forward to provide a theoretical basis.%根据砷在水体中的存在形式、性质和毒性,简要介绍了含砷饮用水的几种常规处理方法及其原理、优缺点,重点综述了氧化法的原理及研究进展,并对氧化法在含砷饮用水处理中的应用进行了展望,以期为氧化法在含砷饮用水处理中的应用提供理论依据.

  12. DNAJC6 promotes hepatocellular carcinoma progression through induction of epithelial–mesenchymal transition

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tao [Hepatobiliary Surgery, The First Hospital of Shijiazhuang City, Shijiazhuang 050011 (China); Li, Xiao-Na [General Surgery, Sports Science Institute of Hebei Province, Shijiazhuang 050011 (China); Li, Xing-Guang; Li, Ming [General Surgery, The First Hospital of Shijiazhuang City, Shijiazhuang 050011 (China); Gao, Peng-Zhi, E-mail: pengzhigaovip@163.com [Hepatobiliary Surgery, The First Hospital of Shijiazhuang City, Shijiazhuang 050011 (China)

    2014-12-12

    Highlights: • DNAJC6 is up-regulated in hepatocellular carcinoma tissues. • DNAJC6 promotes hepatocellular carcinoma cell proliferation and invasion. • DNAJC6 induces epithelial–mesenchymal transition by activating transforming growth factor β signaling. - Abstract: Epithelial–mesenchymal transition (EMT) is a developmental program, which is associated with hepatocellular carcinoma (HCC) development and progression. DNAJC6 (DNA/HSP40 homolog subfamily C member 6) encodes auxilin, which is responsible for juvenile Parkinsonism with phenotypic variability. However, the role of DNAJC6 in HCC development and progression is limited. Here, we report that DNAJC6 is up-regulated in HCC tissues and up-regulation of DNAJC6 expression predicts poor outcome in patients with HCC. Furthermore, overexpression of DNAJC6 enhances the ability for acquisition of mesenchymal traits, enhanced cell proliferation and invasion. DNAJC6 positively regulated expression of EMT-related transcription factor, also activating transforming growth factor β (TGF-β) pathway to contribute to EMT. Our findings demonstrated an important function of DNAJC6 in the progression of HCC by induction of EMT, and they implicate DNAJC6 as a marker of poor outcome in HCC.

  13. Magnetic shielding accelerates the proliferation of human neuroblastoma cell by promoting G1-phase progression.

    Directory of Open Access Journals (Sweden)

    Wei-chuan Mo

    Full Text Available Organisms have been exposed to the geomagnetic field (GMF throughout evolutionary history. Exposure to the hypomagnetic field (HMF by deep magnetic shielding has recently been suggested to have a negative effect on the structure and function of the central nervous system, particularly during early development. Although changes in cell growth and differentiation have been observed in the HMF, the effects of the HMF on cell cycle progression still remain unclear. Here we show that continuous HMF exposure significantly increases the proliferation of human neuroblastoma (SH-SY5Y cells. The acceleration of proliferation results from a forward shift of the cell cycle in G1-phase. The G2/M-phase progression is not affected in the HMF. Our data is the first to demonstrate that the HMF can stimulate the proliferation of SH-SY5Y cells by promoting cell cycle progression in the G1-phase. This provides a novel way to study the mechanism of cells in response to changes of environmental magnetic field including the GMF.

  14. Magnetic shielding accelerates the proliferation of human neuroblastoma cell by promoting G1-phase progression.

    Science.gov (United States)

    Mo, Wei-chuan; Zhang, Zi-jian; Liu, Ying; Bartlett, Perry F; He, Rong-qiao

    2013-01-01

    Organisms have been exposed to the geomagnetic field (GMF) throughout evolutionary history. Exposure to the hypomagnetic field (HMF) by deep magnetic shielding has recently been suggested to have a negative effect on the structure and function of the central nervous system, particularly during early development. Although changes in cell growth and differentiation have been observed in the HMF, the effects of the HMF on cell cycle progression still remain unclear. Here we show that continuous HMF exposure significantly increases the proliferation of human neuroblastoma (SH-SY5Y) cells. The acceleration of proliferation results from a forward shift of the cell cycle in G1-phase. The G2/M-phase progression is not affected in the HMF. Our data is the first to demonstrate that the HMF can stimulate the proliferation of SH-SY5Y cells by promoting cell cycle progression in the G1-phase. This provides a novel way to study the mechanism of cells in response to changes of environmental magnetic field including the GMF.

  15. Interferon Regulatory Factor 7 Promoted Glioblastoma Progression and Stemness by Modulating IL-6 Expression in Microglia

    Science.gov (United States)

    Li, Zongze; Huang, Qiming; Chen, Heping; Lin, Zhiqin; Zhao, Meng; Jiang, Zhongli

    2017-01-01

    Background: Interferon Regulatory Factor 7 (IRF7) is associated with chronic inflammation initiated by the activation of microglia. However it remains poorly defined how IRF7 activates microglia to initiate inflammatory microenvironment, and thus promotes the growth and malignancy of glioblastoma multiforme (GBM). This study investigated the role of IRF7 expression in microglia which increases GBM progression. Methods: We established stable human microglia (HMs) over-expressing IRF-7 or empty vector by lentiviral transduction and stable selection. These HM-IRF-7 cells were co-cultured with U87-MG to examine their influence on GBM, in terms of cell proliferation, apoptosis and stemness of U87-MG. By qRT-PCR and ELISA assays, the expression of key genes and secretion of inflammatory factors were identified in inflammatory signal pathway respectively. We also analyzed whether the expression of IRF7 and its target gene IL-6 correlated with PFS (progression-free survival) and OS (overall survival) in clinical samples by Kaplan-Meier survival curves. Results: HMs can be engineered to stably express high level of IFR7 with IRF7 lentivirus, and was found to promote U87-MG growth and inhibit its apoptosis in co-culture. Meanwhile, U87-MG seemed to show stem cell character with ALDH1 expression. These results may be related to IRF7 initiating IL-6 expression and secretion in both HM and U87-MG cells. The IRF7 and IL-6 were highly expressed in GBM tissues, and IL-6 secretion was high in GBM serums, both of which were significantly correlated with PFS and OS. Conclusions: The immune function of HMs was changed while it expressed IRF7 genes. The results demonstrated for the first time that IRF7 of microglia promoted GBM growth and stemness by mediating IL-6 expression, and revealed that IRF-7 and IL-6 were independent factors affecting the overall survival probability.

  16. CD147 promotes melanoma progression through hypoxia-induced MMP2 activation.

    Science.gov (United States)

    Zeng, W; Su, J; Wu, L; Yang, D; Long, T; Li, D; Kuang, Y; Li, J; Qi, M; Zhang, J; Chen, X

    2014-01-01

    Hypoxia enhances MMP2 expression and the invasion and metastatic potential of melanoma cells. CD147 has been shown to induce MMP2 in multiple cancers. To investigate the role of CD147 in hypoxiainduced MMP2 activation, we performed immunohistochemistry (IHC) staining in 206 normal and melanoma tissue samples, and analyzed the correlation between HIF1α and CD147. ChIP (chromosome Immunoprecipitation) in melanoma cell lines supports that HIF1α directly binds to CD147 promoter. Moreover, we made a series of deletion mutants of CD147 promoter, and identified a conserved HIF1α binding site. Point mutation in this site significantly decreased CD147 response to hypoxia. Importantly, knocking down CD147 attenuates MMP2 response to hypoxia in melanoma cell lines. MMP2 could not be efficiently activated by hypoxia in CD147 depletion cells. ELISA data showed that MMP2 secretion was reduced in CD147 depletion cells than control under hypoxia condition. To verify the data from cell culture model, we performed in vivo mouse xenograft experiment. IHC staining showed reduced MMP2 level in CD147 depleted xenografts compared to the control group, with the HIF1α level being comparable. Our study demonstrates a novel pathway mediated by CD147 to promote the MMP2 activation induced by hypoxia, and helps to understand the interplay between hypoxia and melanoma progression.

  17. Developing and testing theory-based and evidence-based interventions to promote switching to arsenic-safe wells in Bangladesh.

    Science.gov (United States)

    Inauen, Jennifer; Mosler, Hans-Joachim

    2014-12-01

    Millions of people in Bangladesh drink arsenic-contaminated water despite increased awareness of consequences to health. Theory-based and evidence-based interventions are likely to have greater impact on people switching to existing arsenic-safe wells than providing information alone. To test this assumption, we first developed interventions based on an empirical test of the Risk, Attitudes, Norms, Abilities and Self-regulation (RANAS) model of behaviour change. In the second part of this study, a cluster-randomised controlled trial revealed that in accordance with our hypotheses, information alone showed smaller increases in switching to arsenic-safe wells than information with reminders or information with reminders and implementation intentions.

  18. FGF19 Contributes to Tumor Progression in Gastric Cancer by Promoting Migration and Invasion.

    Science.gov (United States)

    Wang, Shuang; Zhao, Daqi; Tian, Ruihua; Shi, Hailong; Chen, Xiangming; Liu, Wenzhi; Wei, Lin

    2016-01-01

    Gastric cancer is the fourth most common type of cancer and second leading cause of cancer-related death in the world. Since patients are often diagnosed at a late stage, very few effective therapies are left in the arsenal. FGF19, as a hormone, has been reported to promote tumor growth in various types of cancer; however, its function in gastric cancer remains unknown. In the current study, we showed that FGF19 is overexpressed in gastric cancer and is associated with depth of invasion, lymph node metastasis, and TNM stage. In addition, in vitro experiments demonstrated that FGF19 is able to enhance migration and invasion abilities of gastric cancer cells. Given its great potency in gastric cancer progression, FGF19 may be an effective target of treatment for advanced gastric cancer patients.

  19. Study on Causes of Slow Progress in Promoting the Application of Food Traceability System in China

    Institute of Scientific and Technical Information of China (English)

    Pinghua; HE; Peisi; CHEN

    2014-01-01

    Chinese government has attempted to promote food traceability system with all strength,but the application process of this system is very slow. The reason is that the adopters have a low level of system application,which causes the system to be invalid at the source of traceability. This paper applies literature research method to analyze the influencing factors for slow application process of the food traceability system in China from various angles including manufacturer,technology,consumer and law,and further concludes that the applying intention of manufacturers,cognizing and purchasing intentions of consumers,and legal environment are important factors for slow progress of system application. On the basis of the research conclusions,the paper proposes practical ways for better construction of food traceability system in China.

  20. Oral health information systems--towards measuring progress in oral health promotion and disease prevention

    DEFF Research Database (Denmark)

    Petersen, Poul Erik; Bourgeois, Denis; Bratthall, Douglas

    2005-01-01

    programmes oriented towards disease prevention and health promotion. The WHO Oral Health Country/Area Profile Programme (CAPP) provides data on oral health from countries, as well as programme experiences and ideas targeted to oral health professionals, policy-makers, health planners, researchers...... systems are being developed within the framework of the WHO STEPwise approach to surveillance of noncommunicable, chronic disease, and data stored in the WHO Global InfoBase may allow advanced health systems research. Sound knowledge about progress made in prevention of oral and chronic disease......This article describes the essential components of oral health information systems for the analysis of trends in oral disease and the evaluation of oral health programmes at the country, regional and global levels. Standard methodology for the collection of epidemiological data on oral health has...

  1. TRIM5α Promotes Ubiquitination of Rta from Epstein–Barr Virus to Attenuate Lytic Progression

    Science.gov (United States)

    Huang, Hsiang-Hung; Chen, Chien-Sin; Wang, Wen-Hung; Hsu, Shih-Wei; Tsai, Hsiao-Han; Liu, Shih-Tung; Chang, Li-Kwan

    2017-01-01

    Replication and transcription activator (Rta), a key protein expressed by Epstein–Barr virus (EBV) during the immediate-early stage of the lytic cycle, is responsible for the activation of viral lytic genes. In this study, GST-pulldown and coimmunoprecipitation assays showed that Rta interacts in vitro and in vivo with TRIM5α, a host factor known to be involved in the restriction of retroviral infections. Confocal microscopy results revealed that Rta colocalizes with TRIM5α in the nucleus during lytic progression. The interaction involves 190 amino acids in the N-terminal of Rta and the RING domain in TRIM5α, and it was further found that TRIM5α acts as an E3 ubiquitin ligase to promote Rta ubiquitination. Overexpression of TRIM5α reduced the transactivating capabilities of Rta, while reducing TRIM5α expression enhanced EBV lytic protein expression and DNA replication. Taken together, these results point to a critical role for TRIM5α in attenuating EBV lytic progression through the targeting of Rta for ubiquitination, and suggest that the restrictive capabilities of TRIM5α may go beyond retroviral infections. PMID:28105027

  2. Overexpression of transcriptional coactivator AIB1 promotes hepatocellular carcinoma progression by enhancing cell proliferation and invasiveness.

    Science.gov (United States)

    Xu, Y; Chen, Q; Li, W; Su, X; Chen, T; Liu, Y; Zhao, Y; Yu, C

    2010-06-10

    Amplified in breast cancer 1 (AIB1) is a transcriptional coactivator for nuclear receptors and other transcription factors. AIB1 has an important role in malignancy of several cancers such as breast and prostate cancers. However, its involvement in human hepatocellular carcinoma (HCC) progression remains unclear. Here, we found that AIB1 protein was overexpressed in 23 of 34 human HCC specimens (68%). Down-regulation of AIB1 reduced HCC cell proliferation, migration, invasion, colony formation ability and tumorigenic potential in nude mice. These phenotypic changes caused by AIB1 knockdown correlated with increased expression of the cell cycle inhibitor p21(Cip1/Waf1) and decreased Akt activation and the expression of proliferating cell nuclear antigen (PCNA) and matrix metallopeptidase MMP-9. In agreement with these findings, clinical AIB1-positive HCC expressed higher levels of PCNA than AIB1-negative HCC. A positive correlation was established between the levels of AIB1 protein and PCNA protein in HCC, suggesting that AIB1 may contribute to HCC cell proliferation. In addition, MMP-9 expression in AIB1-postive HCC was significantly higher than that in AIB1-negative HCC, suggesting that AIB1-postive HCC may be more invasive. Collectively, our results show that overexpression of AIB1 promotes human HCC progression by enhancing cell proliferation and invasiveness. Therefore, AIB1 is a master regulator of human HCC growth and might be a useful molecular target for HCC prognosis and treatment.

  3. Spontaneous initiation, promotion and progression of colorectal cancer in the novel A/J Min/+ mouse.

    Science.gov (United States)

    Sødring, Marianne; Gunnes, Gjermund; Paulsen, Jan Erik

    2016-04-15

    The C57BL/6J multiple intestinal neoplasia (Min/+) mouse is a widely used murine model for familial adenomatous polyposis, a hereditary form of human colorectal cancer. However, it is a questionable model partly because the vast majority of tumors arise in the small intestine, and partly because the fraction of tumors that progress to invasive carcinomas is minuscule. A/J mice are typically more susceptible to carcinogen-induced colorectal cancer than C57BL/6J mice. To investigate whether the novel Min/+ mouse on the A/J genetic background could be a better model for colorectal cancer, we examined the spontaneous intestinal tumorigenesis in 81 A/J Min/+ mice ranging in age from 4 to 60 weeks. The A/J Min/+ mouse exhibited a dramatic increase in number of colonic lesions when compared to what has been reported for the conventional Min/+ mouse; however, an increase in small intestinal lesions did not occur. In addition, this novel mouse model displayed a continual development of colonic lesions highlighted by the transition from early lesions (flat ACF) to tumors over time. In mice older than 40 weeks, 13 colonic (95% CI: 8.7-16.3) and 21 small intestinal (95% CI: 18.6-24.3) tumors were recorded. Notably, a considerable proportion of those lesions progressed to carcinomas in both the colon (21%) and small intestine (51%). These findings more closely reflect aspects of human colorectal carcinogenesis. In conclusion, the novel A/J Min/+ mouse may be a relevant model for initiation, promotion and progression of colorectal cancer.

  4. PCAF-primed EZH2 acetylation regulates its stability and promotes lung adenocarcinoma progression

    Institute of Scientific and Technical Information of China (English)

    Wan Junhu; Chin Y Eugene; Zhang Hongquan; Zhan Jun; Li Shuai; Ma Ji; Xu Weizhi; Liu Chang; Xue Xiaowei; Xie Yuping; Fang Weigang

    2015-01-01

    Enhancer of zeste homolog 2 ( EZH2 ) is a key epigenetic regulator that catalyzes the trimethyla-tion of H3K27 and is modulated by post-translational modifications (PTMs). However, the precise regulation of EZH2 PTMs remains elusive. We, herein, report that EZH2 is acetylated by acetyltransferase P300/CBP-associat-ed factor (PCAF) and is deacetylated by deacetylase SIRT1. We identified that PCAF interacts with and acetylates EZH2 mainly at lysine 348 (K348). Mechanistically, K348 acetylation decreases EZH2 phosphorylation at T345 and T487 and increases EZH2 stability without disrupting the formation of polycomb repressive complex 2 ( PRC2 ) . Functionally, EZH2 K348 acetylation enhances its capacity in suppression of the target genes and promotes lung cancer cell migration and invasion. Further, elevated EZH2 K348 acetylation in lung adenocarcinoma patients pre-dicts a poor prognosis. Our findings define a new mechanism underlying EZH2 modulation by linking EZH2 acety-lation to its phosphorylation that stabilizes EZH2 and promotes lung adenocarcinoma progression.

  5. O-GlcNAcylation of histone deacetylases 1 in hepatocellular carcinoma promotes cancer progression.

    Science.gov (United States)

    Zhu, Guizhou; Tao, Tao; Zhang, Dongmei; Liu, Xiaojuan; Qiu, Huiyuan; Han, LiJian; Xu, Zhiwei; Xiao, Ying; Cheng, Chun; Shen, Aiguo

    2016-08-01

    Hepatocellular carcinoma (HCC) is a malignant tumor originating in the liver. Previous studies have indicated that O-GlcNAc transferase (OGT) and histone deacetylase-1 (HDAC1) play important roles in the pathogenesis of HCC. In the present study, we investigated the physical link between OGT and HDAC1. The O-GlcNAcylation of HDAC1 is overexpressed in HCC. We found that HDAC1 has two major sites of O-GlcNAcylation in its histone deacetylase domain. HDAC1 O-GlcNAcylation increases the activated phosphorylation of HDAC1, which enhances its enzyme activity. HDAC1 O-GlcNAc mutants promote the p21 transcription regulation through affecting the acetylation levels of histones from chromosome, and then influence the proliferation of HCC cells. We also found that mutants of O-GlcNAcylation site of HDAC1 affect invasion and migration of HepG2 cells. E-cadherin level is highly up-regulated in HDAC1 O-GlcNAc mutant-treated liver cancer cells, which inhibit the occurrence and development of HCC. Our findings suggest that OGT promotes the O-GlcNAc modification of HDAC1in the development of HCC. Therefore, inhibiting O-GlcNAcylation of HDAC1 may repress the progression of HCC.

  6. Research Progress on Molecular Mechanisms of Arsenic- induced Oxidative Stress%砷的氧化应激分子机制研究进展

    Institute of Scientific and Technical Information of China (English)

    白彩军; 刘丹; 李冰

    2012-01-01

    砷暴露能够引起多种疾病和病理损伤.目前氧化应激机制是砷毒性的研究热点.砷通过扰乱氧化/抗氧化平衡,从而引起细胞信号通路和转录因子活性、细胞周期和细胞凋亡、线粒体、抗氧化物酶的活性、抗氧化防御系统等方面的改变.本文将就砷的氧化应激分子机制的研究进展进行综述.%Arsenic exposure can cause a variety of diseases and pathological damages. In recent years, oxidative stress mechanism has been considered to be the research focus of arsenic toxicity. Arsenic alters multiple cellular pathways and transcription factor activities, cell cycle and cell apoptosis, mitochondria, antioxidant enzymes activity, and antioxidant defense system by disturbing the pro/antioxidant balance. This review summarizes the molecular mechanism of arsenic- induced oxidative stress.

  7. Earth Abides Arsenic Biotransformations

    Science.gov (United States)

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P.

    2015-01-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice. PMID:26778863

  8. Earth Abides Arsenic Biotransformations

    Science.gov (United States)

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P.

    2014-05-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice.

  9. Activation of PPARγ in myeloid cells promotes lung cancer progression and metastasis.

    Directory of Open Access Journals (Sweden)

    Howard Li

    Full Text Available Activation of peroxisome proliferator-activated receptor-γ (PPARγ inhibits growth of cancer cells including non-small cell lung cancer (NSCLC. Clinically, use of thiazolidinediones, which are pharmacological activators of PPARγ is associated with a lower risk of developing lung cancer. However, the role of this pathway in lung cancer metastasis has not been examined well. The systemic effect of pioglitazone was examined in two models of lung cancer metastasis in immune-competent mice. In an orthotopic model, murine lung cancer cells implanted into the lungs of syngeneic mice metastasized to the liver and brain. As a second model, cancer cells injected subcutaneously metastasized to the lung. In both models systemic administration of pioglitazone increased the rate of metastasis. Examination of tissues from the orthotopic model demonstrated increased numbers of arginase I-positive macrophages in tumors from pioglitazone-treated animals. In co-culture experiments of cancer cells with bone marrow-derived macrophages, pioglitazone promoted arginase I expression in macrophages and this was dependent on the expression of PPARγ in the macrophages. To assess the contribution of PPARγ in macrophages to cancer progression, experiments were performed in bone marrow-transplanted animals receiving bone marrow from Lys-M-Cre+/PPARγ(flox/flox mice, in which PPARγ is deleted specifically in myeloid cells (PPARγ-Mac(neg, or control PPARγ(flox/flox mice. In both models, mice receiving PPARγ-Mac(neg bone marrow had a marked decrease in secondary tumors which was not significantly altered by treatment with pioglitazone. This was associated with decreased numbers of arginase I-positive cells in the lung. These data support a model in which activation of PPARγ may have opposing effects on tumor progression, with anti-tumorigenic effects on cancer cells, but pro-tumorigenic effects on cells of the microenvironment, specifically myeloid cells.

  10. Ssrp1a controls organogenesis by promoting cell cycle progression and RNA synthesis

    Science.gov (United States)

    Koltowska, Katarzyna; Apitz, Holger; Stamataki, Despina; Hirst, Elizabeth M. A.; Verkade, Heather; Salecker, Iris; Ober, Elke A.

    2013-01-01

    Tightly controlled DNA replication and RNA transcription are essential for differentiation and tissue growth in multicellular organisms. Histone chaperones, including the FACT (facilitates chromatin transcription) complex, are central for these processes and act by mediating DNA access through nucleosome reorganisation. However, their roles in vertebrate organogenesis are poorly understood. Here, we report the identification of zebrafish mutants for the gene encoding Structure specific recognition protein 1a (Ssrp1a), which, together with Spt16, forms the FACT heterodimer. Focussing on the liver and eye, we show that zygotic Ssrp1a is essential for proliferation and differentiation during organogenesis. Specifically, gene expression indicative of progressive organ differentiation is disrupted and RNA transcription is globally reduced. Ssrp1a-deficient embryos exhibit DNA synthesis defects and prolonged S phase, uncovering a role distinct from that of Spt16, which promotes G1 phase progression. Gene deletion/replacement experiments in Drosophila show that Ssrp1b, Ssrp1a and N-terminal Ssrp1a, equivalent to the yeast homologue Pob3, can substitute Drosophila Ssrp function. These data suggest that (1) Ssrp1b does not compensate for Ssrp1a loss in the zebrafish embryo, probably owing to insufficient expression levels, and (2) despite fundamental structural differences, the mechanisms mediating DNA accessibility by FACT are conserved between yeast and metazoans. We propose that the essential functions of Ssrp1a in DNA replication and gene transcription, together with its dynamic spatiotemporal expression, ensure organ-specific differentiation and proportional growth, which are crucial for the forming embryo. PMID:23515471

  11. G beta gamma signaling reduces intracellular cAMP to promote meiotic progression in mouse oocytes.

    Science.gov (United States)

    Gill, Arvind; Hammes, Stephen R

    2007-02-01

    In nearly every vertebrate species, elevated intracellular cAMP maintains oocytes in prophase I of meiosis. Prior to ovulation, gonadotropins trigger various intra-ovarian processes, including the breakdown of gap junctions, the activation of EGF receptors, and the secretion of steroids. These events in turn decrease intracellular cAMP levels in select oocytes to allow meiotic progression, or maturation, to resume. Studies suggest that cAMP levels are kept elevated in resting oocytes by constitutive G protein signaling, and that the drop in intracellular cAMP that accompanies maturation may be due in part to attenuation of this inhibitory G protein-mediated signaling. Interestingly, one of these G protein regulators of meiotic arrest is the Galpha(s) protein, which stimulates adenylyl cyclase to raise intracellular cAMP in two important animal models of oocyte development: Xenopus leavis frogs and mice. In addition to G(alpha)(s), constitutive Gbetagamma activity similarly stimulates adenylyl cyclase to raise cAMP and prevent maturation in Xenopus oocytes; however, the role of Gbetagamma in regulating meiosis in mouse oocytes has not been examined. Here we show that Gbetagamma does not contribute to the maintenance of murine oocyte meiotic arrest. In fact, contrary to observations in frog oocytes, Gbetagamma signaling in mouse oocytes reduces cAMP and promotes oocyte maturation, suggesting that Gbetagamma might in fact play a positive role in promoting oocyte maturation. These observations emphasize that, while many general concepts and components of meiotic regulation are conserved from frogs to mice, specific differences exist that may lead to important insights regarding ovarian development in vertebrates.

  12. Defining and implementing arsenic policies in Bangladesh: possible roles for public and private sector actors.

    Science.gov (United States)

    Mahmood, Shakeel Ahmed Ibne; Ball, Carolyn

    2004-01-01

    A UN report warned up to 50% of Bangladesh's population (57 million) are at risk of arsenic poisoning from naturally occurring arsenic in well water. This article explores how this problem occurred, assesses what factors impede progress eliminating this problem and recommends governmental measures for prevention of arsenic poisoning.

  13. MGMT promoter hypermethylation is a frequent, early, and consistent event in astrocytoma progression, and not correlated with TP53 mutation

    NARCIS (Netherlands)

    F.H. Groenendijk (Floris); W. Taal (Walter); H.J. Dubbink (Erik Jan); C.R. Haarloo (Cathleen); M.C.M. Kouwenhoven (Mathilde); M.J. van den Bent (Martin); J.M. Kros (Johan); W.N.M. Dinjens (Winand)

    2011-01-01

    textabstractHypermethylation of the MGMT gene promoter and mutation of the TP53 tumor-suppressor gene are frequently present in diffuse astrocytomas. However, there is only anecdotal information about MGMT methylation status and TP53 mutations during progression of low-grade diffuse astrocytoma (AII

  14. FoxD3 deficiency promotes breast cancer progression by induction of epithelial–mesenchymal transition

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Tian-Li [Department of General Surgery, The People’s Hospital of Wuqing, Tianjin (China); Zhao, Hong-Meng [Key Laboratory of Breast Cancer Prevention and Treatment of the Ministry of Education, Tianjin Medical University Cancer Institute and Hospital, Tianjin (China); Breast Surgery, Tianjin Medical University Cancer Institute and Hospital, Tianjin (China); Li, Yue [Department of Respiration, Affiliated Hospital of Medical College of Chinese People’s Armed Police Force, Tianjin (China); Chen, Ao-Xiang; Sun, Xuan [Key Laboratory of Breast Cancer Prevention and Treatment of the Ministry of Education, Tianjin Medical University Cancer Institute and Hospital, Tianjin (China); Breast Surgery, Tianjin Medical University Cancer Institute and Hospital, Tianjin (China); Ge, Jie, E-mail: gejie198003@163.com [Key Laboratory of Breast Cancer Prevention and Treatment of the Ministry of Education, Tianjin Medical University Cancer Institute and Hospital, Tianjin (China); Breast Surgery, Tianjin Medical University Cancer Institute and Hospital, Tianjin (China)

    2014-04-04

    Highlights: • FOXD3 is down-regulated in breast cancer tissues. • FOXD3 inhibits breast cancer cell proliferation and invasion. • FoxD3 deficiency induces epithelial–mesenchymal transition. - Abstract: The transcription factor forkhead box D3 (FOXD3) plays an important role in the development of neural crest and gastric cancer cells. However, the function and mechanisms of FOXD3 in the breast tumorigenesis and progression is still limited. Here, we report that FOXD3 is a tumor suppressor of breast cancer tumorigenicity and aggressiveness. We found that FOXD3 is down-regulated in breast cancer tissues. Patients with low FOXD3 expression have a poor outcome. Depletion of FOXD3 expression promotes breast cancer cell proliferation and invasion in vitro, whereas overexpression of FOXD3 inhibits breast cancer cell proliferation and invasion both in vitro and in vivo. In addition, depletion of FOXD3 is linked to epithelial–mesenchymal transition (EMT)-like phenotype. Our results indicate FOXD3 exhibits tumor suppressive activity and may be useful for breast therapy.

  15. Small Interfering RNA Targeted to ASPP2 Promotes Progression of Experimental Proliferative Vitreoretinopathy

    Directory of Open Access Journals (Sweden)

    Xiao-Li Chen

    2016-01-01

    Full Text Available Background. Epithelial-mesenchymal transition (EMT of retinal pigment epithelium (RPE is vital in proliferative vitreoretinopathy (PVR development. Apoptosis-stimulating proteins of p53 (ASPP2 have recently been reported to participate in EMT. However, the role of ASPP2 in PVR pathogenesis has not been identified. Methods. Immunohistochemistry was used to investigate the expression of ASPP2 in epiretinal membranes of PVR patients. ARPE-19 cells were transfected with ASPP2-siRNA, followed with measurement of cell cytotoxicity, proliferation, and migration ability. EMT markers and related inflammatory and fibrosis cytokines were measured by western blot or flow cytometry. Additionally, PVR rat models were induced by intravitreal injection of ARPE-19 cells transfected with ASPP2-siRNA and evaluated accordingly. Results. Immunofluorescence analysis revealed less intense expression of ASPP2 in PVR membranes. ASPP2 knockdown facilitated the proliferation and migration of RPE cells and enhanced the expression of mesenchymal markers such as alpha smooth muscle actin, fibronectin, and ZEB1. Meanwhile, ASPP2-siRNA increased EMT-related and inflammatory cytokines, including TGF-β, CTGF, VEGF, TNF-α, and interleukins. PVR severities were more pronounced in the rat models with ASPP2-siRNA treatment. Conclusions. ASPP2 knockdown promoted EMT of ARPE-19 cells in vitro and exacerbated the progression of experimental PVR in vivo, possibly via inflammatory and fibrosis cytokines.

  16. Activin signal promotes cancer progression and is involved in cachexia in a subset of pancreatic cancer.

    Science.gov (United States)

    Togashi, Yosuke; Kogita, Akihiro; Sakamoto, Hiroki; Hayashi, Hidetoshi; Terashima, Masato; de Velasco, Marco A; Sakai, Kazuko; Fujita, Yoshihiko; Tomida, Shuta; Kitano, Masayuki; Okuno, Kiyotaka; Kudo, Masatoshi; Nishio, Kazuto

    2015-01-28

    We previously reported that activin produces a signal with a tumor suppressive role in pancreatic cancer (PC). Here, the association between plasma activin A and survival in patients with advanced PC was investigated. Contrary to our expectations, however, patients with high plasma activin A levels had a significantly shorter survival period than those with low levels (median survival, 314 days vs. 482 days, P = 0.034). The cellular growth of the MIA PaCa-2 cell line was greatly enhanced by activin A via non-SMAD pathways. The cellular growth and colony formation of an INHBA (beta subunit of inhibin)-overexpressed cell line were also enhanced. In a xenograft study, INHBA-overexpressed cells tended to result in a larger tumor volume, compared with a control. The bodyweights of mice inoculated with INHBA-overexpressed cells decreased dramatically, and these mice all died at an early stage, suggesting the occurrence of activin-induced cachexia. Our findings indicated that the activin signal can promote cancer progression in a subset of PC and might be involved in cachexia. The activin signal might be a novel target for the treatment of PC.

  17. Heme oxygenase-1 gene promoter microsatellite polymorphism is associated with progressive atherosclerosis and incident cardiovascular disease

    Science.gov (United States)

    Pechlaner, Raimund; Willeit, Peter; Summerer, Monika; Santer, Peter; Egger, Georg; Kronenberg, Florian; Demetz, Egon; Weiss, Günter; Tsimikas, Sotirios; Witztum, Joseph L.; Willeit, Karin; Iglseder, Bernhard; Paulweber, Bernhard; Kedenko, Lyudmyla; Haun, Margot; Meisinger, Christa; Gieger, Christian; Müller-Nurasyid, Martina; Peters, Annette; Willeit, Johann; Kiechl, Stefan

    2015-01-01

    Objective The enzyme heme oxygenase-1 (HO-1) exerts cytoprotective effects in response to various cellular stressors. A variable number tandem repeat (VNTR) polymorphism in the HO-1 gene promoter region has previously been linked to cardiovascular disease (CVD). We examined this association prospectively in the general population. Approach and Results Incidence of stroke, myocardial infarction, or vascular death was registered between 1995 and 2010 in 812 participants of the Bruneck Study aged 45 to 84 years (49.4% males). Carotid atherosclerosis progression was quantified by high-resolution ultrasound. HO-1 VNTR length was determined by polymerase chain reaction. Subjects with ≥32 tandem repeats on both HO-1 alleles compared to the rest of the population (recessive trait) featured substantially increased CVD risk (hazard ratio [95% confidence interval], 5.45 (2.39, 12.42); PSAPHIR, and KORA prospective studies (HR [95% CI], 3.26 [1.50, 7.33]; P=0.0043). Conclusions This study found a strong association between the HO-1 VNTR polymorphism and CVD risk confined to subjects with a high number of repeats on both HO-1 alleles, and provides evidence for accelerated atherogenesis and decreased anti-oxidant defence in this vascular high-risk group. PMID:25359861

  18. Overexpressed HDAC4 is associated with poor survival and promotes tumor progression in esophageal carcinoma

    Science.gov (United States)

    Mai, Shi-Juan; Wang, Meng-He; Zhang, Mei-Yin; Zheng, X.F. Steven; Wang, Hui-Yun

    2016-01-01

    Histone deacetylases (HDACs) mediate histone deacetylation, leading to transcriptional repression, which is involved in many diseases, including age-related tissue degeneration, heart failure and cancer. In this study, we were aimed to investigate the expression, clinical significance and biological function of HDAC4 in esophageal carcinoma (EC). We found that HDAC4 mRNA and protein are overexpressed in esophageal squamous cell carcinoma (ESCC) tissues and cell lines. HDAC4 overexpression is associated with higher tumor grade, advanced clinical stage and poor survival. Mechanistically, HDAC4 promotes proliferation and G1/S cell cycle progression in EC cells by inhibiting cyclin-dependent kinase (CDK) inhibitors p21 and p27 and up-regulating CDK2/4 and CDK-dependent Rb phosphorylation. HDAC4 also enhances ESCC cell migration. Furthermore, HDAC4 positively regulates epithelial-mesenchymal transition (EMT) by increasing the expression of Vimentin and decreasing the expression of E-Cadherin/α-Catenin. Together, our study shows that HDAC4 overexpression is important for the oncogenesis of EC, which may serve as a useful prognostic biomarker and therapeutic target for this malignancy. PMID:27295551

  19. 联用技术在砷形态分析中的研究进展%Research Progress in the Speciation of Arsenic with Hyphenated Techniques

    Institute of Scientific and Technical Information of China (English)

    李林林; 朱英存

    2013-01-01

    Currently the main analysis techniques for arsenic speciation were the combination of chromatograph with atomic spectrum and mass spectrum, especially the combination of HPLC with ICP-OES or ICP-MS. The methods were accurate and reliable and had high sensitivity. But they can not provide the structural information of arsenic compounds. So the combination of chromatograph with ESI-MS was used as the main method for qualitative analysis. The insufficient sensitivity and vulnerability to matrix interference of ESI-MS can be overcome by the complex pretreatment technique. In this article hyphenated techniques were evaluated with particular emphasis on interfaced separation with element-selective detection and identification of the arsenic compounds detected.%  目前用元素砷的形态分析技术主要是色谱与子光谱、质谱等的联用,最常用的是HPLC与ICP-OES、 ICP-MS的联用,方法准确可靠,灵敏度高,但是不能提供砷化合物的分子结构信息。此以色谱-电喷雾质谱(ESI-MS)的联用作为定性分析的主要手段,但是ESI-MS灵敏度低,易受基体干扰,此需要复杂的前处理技术。

  20. A Study on Promotion and Implementation of Cleaner Production Practices in Malaysian Industry - Development of a National Program and Action Plan for Promotion of Cleaner Production. Progress Report 1

    DEFF Research Database (Denmark)

    Wangel, Arne

    This Progress Report presents the initial findings of the research project 'A Study on Promotion and Implementation of Cleaner Production Practices in Malaysian Industry - Development of a National Program and Action Plan for Promotion of Cleaner Production. Progress Report' funded...... by the Department of Environment, Malaysia...

  1. Inhibition of the soluble epoxide hydrolase promotes albuminuria in mice with progressive renal disease.

    Directory of Open Access Journals (Sweden)

    Oliver Jung

    Full Text Available Epoxyeicotrienoic acids (EETs are cytochrome P450-dependent anti-hypertensive and anti-inflammatory derivatives of arachidonic acid, which are highly abundant in the kidney and considered reno-protective. EETs are degraded by the enzyme soluble epoxide hydrolase (sEH and sEH inhibitors are considered treatment for chronic renal failure (CRF. We determined whether sEH inhibition attenuates the progression of CRF in the 5/6-nephrectomy model (5/6-Nx in mice. 5/6-Nx mice were treated with a placebo, an ACE-inhibitor (Ramipril, 40 mg/kg, the sEH-inhibitor cAUCB or the CYP-inhibitor fenbendazole for 8 weeks. 5/6-Nx induced hypertension, albuminuria, glomerulosclerosis and tubulo-interstitial damage and these effects were attenuated by Ramipril. In contrast, cAUCB failed to lower the blood pressure and albuminuria was more severe as compared to placebo. Plasma EET-levels were doubled in 5/6 Nx-mice as compared to sham mice receiving placebo. Renal sEH expression was attenuated in 5/6-Nx mice but cAUCB in these animals still further increased the EET-level. cAUCB also increased 5-HETE and 15-HETE, which derive from peroxidation or lipoxygenases. Similar to cAUCB, CYP450 inhibition increased HETEs and promoted albuminuria. Thus, sEH-inhibition failed to elicit protective effects in the 5/6-Nx model and showed a tendency to aggravate the disease. These effects might be consequence of a shift of arachidonic acid metabolism into the lipoxygenase pathway.

  2. A novel biomarker C6orf106 promotes the malignant progression of breast cancer.

    Science.gov (United States)

    Jiang, Guiyang; Zhang, Xiupeng; Zhang, Yong; Wang, Liang; Fan, Chuifeng; Xu, Hongtao; Miao, Yuan; Wang, Enhua

    2015-09-01

    C6orf106 (chromosome 6 open reading frame 106) is a recently discovered protein encoded by the 6th chromosome. Though many proteins encoded by chromosome 6 are reportedly related to cancer, schizophrenia, autoimmunity and many other diseases, the function of C6orf106 was not well demonstrated so far. As measured by immunohistochemical staining, C6orf106 was positive in normal breast duct myoepithelial cells (92.31 %, 72/78), but negative in normal breast duct glandular epithelial cells (3.85 %, 3/78). In breast ductal carcinoma in situ, C6orf106 showed weakly or moderately positive (77.97 %, 46/59), but it was significantly strongly positive in invasive ductal carcinoma (79.57 %, 148/186). The expression intensity of C6orf106 seemed increased significantly along with the malignancy of breast cancer (p breast cancer, respectively. Consistently, we found that the interference of C6orf106 was able to inhibit cell proliferation and invasion of two triple-negative breast cancer cell lines, MDA-MB-231 and BT-549, accompanied by the decrease of cyclin A2, cyclin B1, c-myc, and N-cadherin and the increase of E-cadherin. Collectively, these results indicate that C6orf106 may promote tumor progression in the invasive breast cancer, particularly in triple-negative breast cancer, and C6orf106 might serve as a novel therapeutic target of breast cancer, especially for triple-negative breast cancer.

  3. Cryptic exposure to arsenic.

    Science.gov (United States)

    Rossy, Kathleen M; Janusz, Christopher A; Schwartz, Robert A

    2005-01-01

    Arsenic is an odorless, colorless and tasteless element long linked with effects on the skin and viscera. Exposure to it may be cryptic. Although human intake can occur from four forms, elemental, inorganic (trivalent and pentavalent arsenic) and organic arsenic, the trivalent inorganic arsenicals constitute the major human hazard. Arsenic usually reaches the skin from occupational, therapeutic, or environmental exposure, although it still may be employed as a poison. Occupations involving new technologies are not exempt from arsenic exposure. Its acute and chronic effects are noteworthy. Treatment options exist for arsenic-induced pathology, but prevention of toxicity remains the main focus. Vitamin and mineral supplementation may play a role in the treatment of arsenic toxicity.

  4. Arsenic Trioxide Injection

    Science.gov (United States)

    Arsenic trioxide is used to treat acute promyelocytic leukemia (APL; a type of cancer in which there ... worsened following treatment with other types of chemotherapy. Arsenic trioxide is in a class of medications called ...

  5. Cryptic exposure to arsenic

    Directory of Open Access Journals (Sweden)

    Rossy Kathleen

    2005-01-01

    Full Text Available Arsenic is an odorless, colorless and tasteless element long linked with effects on the skin and viscera. Exposure to it may be cryptic. Although human intake can occur from four forms, elemental, inorganic (trivalent and pentavalent arsenic and organic arsenic, the trivalent inorganic arsenicals constitute the major human hazard. Arsenic usually reaches the skin from occupational, therapeutic, or environmental exposure, although it still may be employed as a poison. Occupations involving new technologies are not exempt from arsenic exposure. Its acute and chronic effects are noteworthy. Treatment options exist for arsenic-induced pathology, but prevention of toxicity remains the main focus. Vitamin and mineral supplementation may play a role in the treatment of arsenic toxicity.

  6. Arsenic efflux from Microcystis aeruginosa under different phosphate regimes.

    Directory of Open Access Journals (Sweden)

    Changzhou Yan

    Full Text Available Phytoplankton plays an important role in arsenic speciation, distribution, and cycling in freshwater environments. Little information, however, is available on arsenic efflux from the cyanobacteria Microcystis aeruginosa under different phosphate regimes. This study investigated M. aeruginosa arsenic efflux and speciation by pre-exposing it to 10 µM arsenate or arsenite for 24 h during limited (12 h and extended (13 d depuration periods under phosphate enriched (+P and phosphate depleted (-P treatments. Arsenate was the predominant species detected in algal cells throughout the depuration period while arsenite only accounted for no greater than 45% of intracellular arsenic. During the limited depuration period, arsenic efflux occurred rapidly and only arsenate was detected in solutions. During the extended depuration period, however, arsenate and dimethylarsinic acid (DMA were found to be the two predominant arsenic species detected in solutions under -P treatments, but arsenate was the only species detected under +P treatments. Experimental results also suggest that phosphorus has a significant effect in accelerating arsenic efflux and promoting arsenite bio-oxidation in M. aeruginosa. Furthermore, phosphorus depletion can reduce arsenic efflux from algal cells as well as accelerate arsenic reduction and methylation. These findings can contribute to our understanding of arsenic biogeochemistry in aquatic environments and its potential environmental risks under different phosphorus levels.

  7. Postmenopausal obesity promotes tumor angiogenesis and breast cancer progression in mice.

    Science.gov (United States)

    Gu, Jian-Wei; Young, Emily; Patterson, Sharla G; Makey, Kristina L; Wells, Jeremy; Huang, Min; Tucker, Kevan B; Miele, Lucio

    2011-05-15

    Obese postmenopausal women have a 50% higher risk of breast cancer than non-obese women. There is not an animal model that mimics postmenopausal obesity related to breast cancer progression. Using age-relevant C57BL/6 mice, this study determined whether postmenopausal obesity increases VEGF expression, tumor angiogenesis, and breast tumor growth. Ovariectomy (OVX) was performed in 12 sixty week-old female mice, then followed by a low-fat (5%, LF, n=6) or a high-fat (60%, HF, n=6) diet for 12 weeks. In the eighth week of the dietary program, 10(6) E0771 (mouse breast cancer) cells were injected in the left fourth mammary gland. Tumor size was monitored for 4 weeks. Body weights were monitored weekly. At the end of the experiment, blood samples, visceral fat and tumors were collected for measuring VEGF expression using ELISA and intratumoral microvessel density (IMD) using CD31 immunochemistry. Body weight was significantly increased in OVX/HF mice, compared to OVX/LF group (55.3±1.7 vs. 41.5±1.5 g; p < 0.01). There was a two-fold increase in the ratio of visceral fat/BW in OVX/HF mice, compared to those in OVX/LF group (0.062±0.005 vs. 0.032±0.003; p < 0.01). Postmenopausal obesity significantly increased breast tumor weight over the control (4.62±0.63 vs. 1.98±0.27 g; p < 0.01) and IMD (173±3.7 vs. 139±4.3 IM#/mm^2; p < 0.01). Tumor VEGF levels were higher in OVX/HF mice, compared to OVX/LF group (73.3±3.8 vs. 49.5±4.3 pg/mg protein; p < 0.01). Plasma VEGF levels (69±7.1 vs. 48±3.5 pg/ml) and visceral fat VEGF levels (424.4±39.5 vs. 208.5±22.4 pg/mg protein) were significantly increased in OVX/HF mice, compared to OVX/LF group, respectively (n=6; p < 0.01). Interestingly, adipose tissue primary culture showed that subcutaneous fat released more VEGF, compared to visceral fat (6.77±1.14 vs. 0.94±0.16 pg/mg tissue; n=6; p < 0.01). These findings support the hypothesis that postmenopausal obesity promotes tumor angiogenesis and breast cancer

  8. δ-Catenin promotes prostate cancer cell growth and progression by altering cell cycle and survival gene profiles

    Directory of Open Access Journals (Sweden)

    Chen Yan-Hua

    2009-03-01

    Full Text Available Abstract Background δ-Catenin is a unique member of β-catenin/armadillo domain superfamily proteins and its primary expression is restricted to the brain. However, δ-catenin is upregulated in human prostatic adenocarcinomas, although the effects of δ-catenin overexpression in prostate cancer are unclear. We hypothesized that δ-catenin plays a direct role in prostate cancer progression by altering gene profiles of cell cycle regulation and cell survival. Results We employed gene transfection and small interfering RNA to demonstrate that increased δ-catenin expression promoted, whereas its knockdown suppressed prostate cancer cell viability. δ-Catenin promoted prostate cancer cell colony formation in soft agar as well as tumor xenograft growth in nude mice. Deletion of either the amino-terminal or carboxyl-terminal sequences outside the armadillo domains abolished the tumor promoting effects of δ-catenin. Quantitative RT2 Profiler™ PCR Arrays demonstrated gene alterations involved in cell cycle and survival regulation. δ-Catenin overexpression upregulated cyclin D1 and cdc34, increased phosphorylated histone-H3, and promoted the entry of mitosis. In addition, δ-catenin overexpression resulted in increased expression of cell survival genes Bcl-2 and survivin while reducing the cell cycle inhibitor p21Cip1. Conclusion Taken together, our studies suggest that at least one consequence of an increased expression of δ-catenin in human prostate cancer is the alteration of cell cycle and survival gene profiles, thereby promoting tumor progression.

  9. Arsenic pollution sources.

    Science.gov (United States)

    Garelick, Hemda; Jones, Huw; Dybowska, Agnieszka; Valsami-Jones, Eugenia

    2008-01-01

    Arsenic is a widely dispersed element in the Earth's crust and exists at an average concentration of approximately 5 mg/kg. There are many possible routes of human exposure to arsenic from both natural and anthropogenic sources. Arsenic occurs as a constituent in more than 200 minerals, although it primarily exists as arsenopyrite and as a constituent in several other sulfide minerals. The introduction of arsenic into drinking water can occur as a result of its natural geological presence in local bedrock. Arsenic-containing bedrock formations of this sort are known in Bangladesh, West Bengal (India), and regions of China, and many cases of endemic contamination by arsenic with serious consequences to human health are known from these areas. Significant natural contamination of surface waters and soil can arise when arsenic-rich geothermal fluids come into contact with surface waters. When humans are implicated in causing or exacerbating arsenic pollution, the cause can almost always be traced to mining or mining-related activities. Arsenic exists in many oxidation states, with arsenic (III) and (V) being the most common forms. Similar to many metalloids, the prevalence of particular species of arsenic depends greatly on the pH and redox conditions of the matrix in which it exists. Speciation is also important in determining the toxicity of arsenic. Arsenic minerals exist in the environment principally as sulfides, oxides, and phosphates. In igneous rocks, only those of volcanic origin are implicated in high aqueous arsenic concentrations. Sedimentary rocks tend not to bear high arsenic loads, and common matrices such as sands and sandstones contain lower concentrations owing to the dominance of quartz and feldspars. Groundwater contamination by arsenic arises from sources of arsenopyrite, base metal sulfides, realgar and orpiment, arsenic-rich pyrite, and iron oxyhydroxide. Mechanisms by which arsenic is released from minerals are varied and are accounted for by

  10. RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Houcai; Yu, Jing; Zhang, Lixia; Xiong, Yuanyuan; Chen, Shuying; Xing, Haiyan; Tian, Zheng; Tang, Kejing; Wei, Hui; Rao, Qing; Wang, Min; Wang, Jianxiang, E-mail: wangjx@ihcams.ac.cn

    2014-04-18

    Highlights: • RPS27a expression was up-regulated in advanced-phase CML and AL patients. • RPS27a knockdown changed biological property of K562 and K562/G01 cells. • RPS27a knockdown affected Raf/MEK/ERK, P21 and BCL-2 signaling pathways. • RPS27a knockdown may be applicable for new combination therapy in CML patients. - Abstract: Ribosomal protein S27a (RPS27a) could perform extra-ribosomal functions besides imparting a role in ribosome biogenesis and post-translational modifications of proteins. The high expression level of RPS27a was reported in solid tumors, and we found that the expression level of RPS27a was up-regulated in advanced-phase chronic myeloid leukemia (CML) and acute leukemia (AL) patients. In this study, we explored the function of RPS27a in leukemia cells by using CML cell line K562 cells and its imatinib resistant cell line K562/G01 cells. It was observed that the expression level of RPS27a was high in K562 cells and even higher in K562/G01 cells. Further analysis revealed that RPS27a knockdown by shRNA in both K562 and K562G01 cells inhibited the cell viability, induced cell cycle arrest at S and G2/M phases and increased cell apoptosis induced by imatinib. Combination of shRNA with imatinib treatment could lead to more cleaved PARP and cleaved caspase-3 expression in RPS27a knockdown cells. Further, it was found that phospho-ERK(p-ERK) and BCL-2 were down-regulated and P21 up-regulated in RPS27a knockdown cells. In conclusion, RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells. It appears that drugs targeting RPS27a combining with tyrosine kinase inhibitor (TKI) might represent a novel therapy strategy in TKI resistant CML patients.

  11. MGMT promoter methylation is associated with temozolomide response and prolonged progression-free survival in disseminated cutaneous melanoma.

    Science.gov (United States)

    Tuominen, Rainer; Jewell, Rosalyn; van den Oord, Joost J; Wolter, Pascal; Stierner, Ulrika; Lindholm, Christer; Hertzman Johansson, Carolina; Lindén, Diana; Johansson, Hemming; Frostvik Stolt, Marianne; Walker, Christy; Snowden, Helen; Newton-Bishop, Julia; Hansson, Johan; Egyházi Brage, Suzanne

    2015-06-15

    To investigate the predictive and prognostic value of O(6) -methylguanine DNA methyltransferase (MGMT) inactivation by analyses of promoter methylation in pretreatment tumor biopsies from patients with cutaneous melanoma treated with dacarbazine (DTIC) or temozolomide (TMZ) were performed. The patient cohorts consisted of Belgian and Swedish disseminated melanoma patients. Patients were subdivided into those receiving single-agent treatment with DTIC/TMZ (cohort S, n = 74) and those treated with combination chemotherapy including DTIC/TMZ (cohort C, n = 79). Median follow-up was 248 and 336 days for cohort S and cohort C, respectively. MGMT promoter methylation was assessed by three methods. The methylation-related transcriptional silencing of MGMT mRNA expression was assessed by real-time RT-PCR. Response to chemotherapy and progression-free survival (PFS) and overall survival were correlated to MGMT promoter methylation status. MGMT promoter methylation was detected in tumor biopsies from 21.5 % of the patients. MGMT mRNA was found to be significantly lower in tumors positive for MGMT promoter methylation compared to tumors without methylation in both treatment cohorts (p MGMT promoter methylation in cohort S (p = 0.0005), but did not reach significance in cohort C (p = 0.16). Significantly longer PFS was observed among patients with MGMT promoter-methylated tumors (p = 0.002). Multivariate Cox regression analysis identified presence of MGMT promoter methylation as an independent variable associated with longer PFS. Together, this implies that MGMT promoter methylation is associated with response to single-agent DTIC/TMZ and longer PFS in disseminated cutaneous melanoma.

  12. Dual therapeutic functions of F-5 fragment in burn wounds: preventing wound progression and promoting wound healing in pigs.

    Science.gov (United States)

    Bhatia, Ayesha; O'Brien, Kathryn; Chen, Mei; Wong, Alex; Garner, Warren; Woodley, David T; Li, Wei

    2016-01-01

    Burn injuries are a leading cause of morbidity including prolonged hospitalization, disfigurement, and disability. Currently there is no Food and Drug Administration-approved burn therapeutics. A clinical distinction of burn injuries from other acute wounds is the event of the so-called secondary burn wound progression within the first week of the injury, in which a burn expands horizontally and vertically from its initial boundary to a larger area. Therefore, an effective therapeutics for burns should show dual abilities to prevent the burn wound progression and thereafter promote burn wound healing. Herein we report that topically applied F-5 fragment of heat shock protein-90α is a dual functional agent to promote burn wound healing in pigs. First, F-5 prevents burn wound progression by protecting the surrounding cells from undergoing heat-induced caspase 3 activation and apoptosis with increased Akt activation. Accordingly, F-5-treated burn and excision wounds show a marked decline in inflammation. Thereafter, F-5 accelerates burn wound healing by stimulating the keratinocyte migration-led reepithelialization, leading to wound closure. This study addresses a topical agent that is capable of preventing burn wound progression and accelerating burn wound healing.

  13. Arsenic removal from water

    Science.gov (United States)

    Moore, Robert C.; Anderson, D. Richard

    2007-07-24

    Methods for removing arsenic from water by addition of inexpensive and commonly available magnesium oxide, magnesium hydroxide, calcium oxide, or calcium hydroxide to the water. The hydroxide has a strong chemical affinity for arsenic and rapidly adsorbs arsenic, even in the presence of carbonate in the water. Simple and commercially available mechanical methods for removal of magnesium hydroxide particles with adsorbed arsenic from drinking water can be used, including filtration, dissolved air flotation, vortex separation, or centrifugal separation. A method for continuous removal of arsenic from water is provided. Also provided is a method for concentrating arsenic in a water sample to facilitate quantification of arsenic, by means of magnesium or calcium hydroxide adsorption.

  14. Arsenic poisoning in livestock.

    Science.gov (United States)

    el Bahri, L; Ben Romdane, S

    1991-06-01

    Arsenic is an important heavy metal intoxicant to livestock. Arsenical pesticides present significant hazards to animal health. The toxicity of arsenic varies with several factors--its chemical form, oxidation states, solubility. The phenylarsonic compounds are the least toxic and are used as feed additives in swine and poultry rations. However, roxarsone has a higher absolute toxicity than arsanilic acid. The mechanism of action is related to its reaction with sulfhydryl groups values to enzyme function and to its ability to uncouple oxydative phosphorylation. Most animals excrete arsenic quite readily. Toxicoses caused by inorganic and aliphatic organic arsenicals result in a different clinical syndrome than that from the phenylarsonic compounds. Arsenic poisoning may be confused with other types of intoxication. The specific antidote for inorganic arsenical poisoning is dimercaprol (BAL).

  15. Arsenic cardiotoxicity: An overview.

    Science.gov (United States)

    Alamolhodaei, Nafiseh Sadat; Shirani, Kobra; Karimi, Gholamreza

    2015-11-01

    Arsenic, a naturally ubiquitous element, is found in foods and environment. Cardiac dysfunction is one of the major causes of morbidity and mortality in the world. Arsenic exposure is associated with various cardiopathologic effects including ischemia, arrhythmia and heart failure. Possible mechanisms of arsenic cardiotoxicity include oxidative stress, DNA fragmentation, apoptosis and functional changes of ion channels. Several evidences have shown that mitochondrial disruption, caspase activation, MAPK signaling and p53 are the pathways for arsenic induced apoptosis. Arsenic trioxide is an effective and potent antitumor agent used in patients with acute promyelocytic leukemia and produces dramatic remissions. As2O3 administration has major limitations such as T wave changes, QT prolongation and sudden death in humans. In this review, we discuss the underlying pathobiology of arsenic cardiotoxicity and provide information about cardiac health effects associated with some medicinal plants in arsenic toxicity.

  16. Ageing and recurrent episodes of neuroinflammation promote progressive experimental autoimmune encephalomyelitis in Biozzi ABH mice.

    Science.gov (United States)

    Peferoen, Laura A N; Breur, Marjolein; van de Berg, Sarah; Peferoen-Baert, Regina; Boddeke, Erik H W G M; van der Valk, Paul; Pryce, Gareth; van Noort, Johannes M; Baker, David; Amor, Sandra

    2016-10-01

    Current therapies for multiple sclerosis (MS) reduce the frequency of relapses by modulating adaptive immune responses but fail to limit the irreversible neurodegeneration driving progressive disability. Experimental autoimmune encephalomyelitis (EAE) in Biozzi ABH mice recapitulates clinical features of MS including relapsing-remitting episodes and secondary-progressive disability. To address the contribution of recurrent inflammatory events and ageing as factors that amplify progressive neurological disease, we examined EAE in 8- to 12-week-old and 12-month-old ABH mice. Compared with the relapsing-remitting (RREAE) and secondary progressive (SPEAE) EAE observed in young mice, old mice developed progressive disease from onset (PEAE) associated with pronounced axonal damage and increased numbers of CD3(+) T cells and microglia/macrophages, but not B cells. Whereas the clinical neurological features of PEAE and SPEAE were comparable, the pathology was distinct. SPEAE was associated with significantly reduced perivascular infiltrates and T-cell numbers in the central nervous system (CNS) compared with PEAE and the acute phase of RREAE. In contrast to perivascular infiltrates that declined during progression from RREAE into SPEAE, the numbers of microglia clusters remained constant. Similar to what is observed during MS, the microglia clusters emerging during EAE were associated with axonal damage and oligodendrocytes expressing heat-shock protein B5, but not lymphocytes. Taken together, our data reveal that the course of EAE is dependent on the age of the mice. Younger mice show a relapsing-remitting phase followed by progressive disease, whereas old mice immediately show progression. This indicates that recurrent episodes of inflammation in the CNS, as well as age, contribute to progressive neurological disease.

  17. Over expression of hyaluronan promotes progression of HCC via CD44-mediated pyruvate kinase M2 nuclear translocation

    Science.gov (United States)

    Li, Jing-Huan; Wang, Ying-Cong; Qin, Cheng-Dong; Yao, Rong-Rong; Zhang, Rui; Wang, Yan; Xie, Xiao-Ying; Zhang, Lan; Wang, Yan-Hong; Ren, Zheng-Gang

    2016-01-01

    Hyaluronan is expressed in hepatocellular carcinoma (HCC) as HCC generally arises from a cirrhotic liver in which excessive production and accumulation of HA leads to developing cirrhosis. Though it has been suggested HA is involved in progression of HCC, the mechanisms underlying the connection between HA and HCC progression are unclear. Since increased aerobic glycolysis is a metabolic trait of malignant cells and HA-CD44 can modulate glucose metabolism, we aim to investigate the roles of PKM2, a key enzyme in glucose metabolism, in the HA-CD44 axis facilitated the progress of HCC. We shown PKM2 was required for HA-promoted HCC progression, which was not modulated by PKM2 kinase activity but by nuclear translocation of PKM2. PKM2 translocation was Erk (Thr202/Tyr204) phosphorylation dependent, which functioned at the downstream of HA-CD44 binding. Furthermore, elevated HA expression significantly correlated with PKM2 nuclear location and was an independent factors predicting poor HCC prognosis. In conclusions PKM2 nuclear translocation is required for mediating the described HA biological effects on HCC progression and our results imply that inhibition of HA may have therapeutic value in treating HCC. PMID:27186420

  18. PRL-3 Promotes the Malignant Progression of Melanoma via Triggering Dephosphorylation and Cytoplasmic Localization of NHERF1.

    Science.gov (United States)

    Fang, Xian-Ying; Song, Ran; Chen, Wei; Yang, Yuan-Yuan; Gu, Yan-Hong; Shu, Yong-Qian; Wu, Xu-Dong; Wu, Xue-Feng; Sun, Yang; Shen, Yan; Xu, Qiang

    2015-09-01

    Phosphatase of regenerating liver-3 (PRL-3) has been reported to have a critical role in metastatic progression of cancers. Here, we investigate how PRL-3 increases the malignant degree of melanoma cells. The expression of PRL-3 increased gradually during the malignant progression of melanoma. The phosphorylation of Akt was elevated in highly malignant melanoma cells, which was accompanied by a decrease in nuclear phosphatase and tensin homolog (PTEN). The phosphorylation of NHERF1 in the serine site was regulated by PRL-3 and showed cytoplasmic translocation upon dephosphorylation, which resulted in a decrease in nuclear PTEN. The co-translocation of NHERF1 and PTEN from the nucleus to the cytoplasm was observed during the malignant progression of melanoma cells. Tumor growth was inhibited significantly, and the survival was prolonged upon knockdown of cytoplasmic NHERF1 in B16BL6 cells prior to the inoculation into mice. Taken together, to our knowledge previously unreported, we have identified NHERF1 as a potential substrate of PRL-3. Its phosphorylation status as well as its change in cellular localization and association with PTEN correlated with the malignant progression of melanoma. Our data provide an explanation for how PRL-3 promotes the malignant progression of melanoma, as well as a diagnostic marker or therapeutic target for malignant melanoma.

  19. Reduction and coordination of arsenic in Indian mustard.

    Science.gov (United States)

    Pickering, I J; Prince, R C; George, M J; Smith, R D; George, G N; Salt, D E

    2000-04-01

    The bioaccumulation of arsenic by plants may provide a means of removing this element from contaminated soils and waters. However, to optimize this process it is important to understand the biological mechanisms involved. Using a combination of techniques, including x-ray absorption spectroscopy, we have established the biochemical fate of arsenic taken up by Indian mustard (Brassica juncea). After arsenate uptake by the roots, possibly via the phosphate transport mechanism, a small fraction is exported to the shoot via the xylem as the oxyanions arsenate and arsenite. Once in the shoot, the arsenic is stored as an As(III)-tris-thiolate complex. The majority of the arsenic remains in the roots as an As(III)-tris-thiolate complex, which is indistinguishable from that found in the shoots and from As(III)-tris-glutathione. The thiolate donors are thus probably either glutathione or phytochelatins. The addition of the dithiol arsenic chelator dimercaptosuccinate to the hydroponic culture medium caused a 5-fold-increased arsenic level in the leaves, although the total arsenic accumulation was only marginally increased. This suggests that the addition of dimercaptosuccinate to arsenic-contaminated soils may provide a way to promote arsenic bioaccumulation in plant shoots, a process that will be essential for the development of an efficient phytoremediation strategy for this element.

  20. OCT4 increases BIRC5 and CCND1 expression and promotes cancer progression in hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Cao Lu

    2013-02-01

    Full Text Available Abstract Background OCT4 and BIRC5 are preferentially expressed in human cancer cells and mediate cancer cell survival and tumor maintenance. However, the molecular mechanism that regulates OCT4 and BIRC5 expression is not well characterized. Methods By manipulating OCT4 and BIRC5 expression in hepatocellular carcinoma (HCC cell lines, the regulatory mechanism of OCT4 on BIRC5 and CCND1 were investigated. Results Increasing or decreasing OCT4 expression could enhance or suppress BIRC5 expression, respectively, by regulating the activity of BIRC5 promoter. Because there is no binding site for OCT4 within BIRC5 promoter, the effect of OCT4 on BIRC5 promoter is indirect. An octamer motif for OCT4 in the CCND1 promoter has directly and partly participated in the regulation of CCND1 promoter activity, suggesting that OCT4 also could upregulated the expression of CCND1. Co-suppression of OCT4 and BIRC5 induced cancer cell apoptosis and cell cycle arrest, thereby efficiently inhibiting the proliferative activity of cancer cells and suppressing the growth of HCC xenogrfts in nude mice. Conclusion OCT4 can upregulate BIRC5 and CCND1 expression by increasing their promoter activity. These factors collusively promotes HCC cell proliferation, and co-suppression of OCT4 and BIRC5 is potentially beneficial for HCC treatment.

  1. PUMA promotes apoptosis of hematopoietic progenitors driving leukemic progression in a mouse model of myelodysplasia.

    Science.gov (United States)

    Guirguis, A A; Slape, C I; Failla, L M; Saw, J; Tremblay, C S; Powell, D R; Rossello, F; Wei, A; Strasser, A; Curtis, D J

    2016-06-01

    Myelodysplastic syndrome (MDS) is characterized by ineffective hematopoiesis with resultant cytopenias. Increased apoptosis and aberrantly functioning progenitors are thought to contribute to this phenotype. As is the case for other malignancies, overcoming apoptosis is believed to be important in progression toward acute myeloid leukemia (AML). Using the NUP98-HOXD13 (NHD13) transgenic mouse model of MDS, we previously reported that overexpression of the anti-apoptotic protein BCL2, blocked apoptosis and improved cytopenias, paradoxically, delaying leukemic progression. To further understand this surprising result, we examined the role of p53 and its pro-apoptotic effectors, PUMA and NOXA in NHD13 mice. The absence of p53 or PUMA but not NOXA reduced apoptosis and expanded the numbers of MDS-repopulating cells. Despite a similar effect on apoptosis and cell numbers, the absence of p53 and PUMA had diametrically opposed effects on progression to AML: absence of p53 accelerated leukemic progression, while absence of PUMA significantly delayed progression. This may be explained in part by differences in cellular responses to DNA damage. The absence of p53 led to higher levels of γ-H2AX (indicative of persistent DNA lesions) while PUMA-deficient NHD13 progenitors resolved DNA lesions in a manner comparable to wild-type cells. These results suggest that targeting PUMA may improve the cytopenias of MDS without a detrimental effect on leukemic progression thus warranting further investigation.

  2. Identification of an arsenic resistance and arsenic-sensing system in Campylobacter jejuni.

    Science.gov (United States)

    Wang, Liping; Jeon, Byeonghwa; Sahin, Orhan; Zhang, Qijing

    2009-08-01

    Arsenic is commonly present in the natural environment and is also used as a feed additive for animal production. Poultry is a major reservoir for Campylobacter jejuni, a major food-borne human pathogen causing gastroenteritis. It has been shown that Campylobacter isolates from poultry are highly resistant to arsenic compounds, but the molecular mechanisms responsible for the resistance have not been determined, and it is unclear if the acquired arsenic resistance affects the susceptibility of Campylobacter spp. to other antimicrobials. In this study, we identified a four-gene operon that contributes to arsenic resistance in Campylobacter. This operon encodes a putative membrane permease (ArsP), a transcriptional repressor (ArsR), an arsenate reductase (ArsC), and an efflux protein (Acr3). PCR analysis of various clinical C. jejuni isolates indicated a significant association of this operon with elevated resistance to arsenite and arsenate. Gene-specific mutagenesis confirmed the role of the ars operon in conferring arsenic resistance. It was further shown that this operon is subject to regulation by ArsR, which directly binds to the ars promoter and inhibits the transcription of the operon. Arsenite inhibits the binding of ArsR to the ars promoter DNA and induces the expression of the ars genes. Mutation of the ars genes did not affect the susceptibility of C. jejuni to commonly used antibiotics. These results identify the ars operon as an important mechanism for arsenic resistance and sensing in Campylobacter.

  3. Science as a Common Language in a Globalised World - Scientific Collaboration Promoting Progress, Building Bridges

    CERN Document Server

    CERN. Geneva. Audiovisual Unit

    2003-01-01

    International scientific collaboration and co-operation can accelerate the progress of science, help build bridges between diverse societies, and foster the development of science and technology in non-industrialised countries. This is possible because science is a common language (although the progress of science is often influenced by non-scientific factors). I shall describe examples of the role that scientific collaboration can play in bridge building and in conflict resolution. I shall then present a proposal for "Bridge Building Fellowships" which would contribute to strengthening scientific capacity in developing countries by helping to stem the brain drain and providing a basis for collaborations with scientists in industrialised countries.

  4. Knockdown of TWIST1 enhances arsenic trioxide- and ionizing radiation-induced cell death in lung cancer cells by promoting mitochondrial dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Sung-Keum; Kim, Jae-Hee; Choi, Ha-Na [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of); Choe, Tae-Boo [Department of Microbiological Engineering, Kon-Kuk University, Gwangjin-gu, Seoul (Korea, Republic of); Hong, Seok-Il [Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of); Yi, Jae-Youn [Laboratory of Modulation of Radiobiological Responses, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of); Hwang, Sang-Gu [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of); Lee, Hyun-Gyu [Department of Microbiology and Immunology, College of Medicine, Yonsei University, 250 Seongsan-no, Seodaemun-gu, Seoul (Korea, Republic of); Lee, Yun-Han, E-mail: yhlee87@yuhs.ac [Department of Radiation Oncology, College of Medicine, Yonsei University, 250 Seongsan-no, Seodaemun-gu, Seoul (Korea, Republic of); Park, In-Chul, E-mail: parkic@kcch.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of)

    2014-07-11

    Highlights: • Knockdown of TWIST1 enhanced ATO- and IR-induced cell death in NSCLCs. • Intracellular ROS levels were increased in cells treated with TWIST1 siRNA. • TWIST1 siRNA induced MMP loss and mitochondrial fragmentation. • TWIST1 siRNA upregulated the fission-related proteins FIS1 and DRP1. - Abstract: TWIST1 is implicated in the process of epithelial mesenchymal transition, metastasis, stemness, and drug resistance in cancer cells, and therefore is a potential target for cancer therapy. In the present study, we found that knockdown of TWIST1 by small interfering RNA (siRNA) enhanced arsenic trioxide (ATO)- and ionizing radiation (IR)-induced cell death in non-small-cell lung cancer cells. Interestingly, intracellular reactive oxygen species levels were increased in cells treated with TWIST1 siRNA and further increased by co-treatment with ATO or IR. Pretreatment of lung cancer cells with the antioxidant N-acetyl-cysteine markedly suppressed the cell death induced by combined treatment with TWIST1 siRNA and ATO or IR. Moreover, treatment of cells with TWIST1 siRNA induced mitochondrial membrane depolarization and significantly increased mitochondrial fragmentation (fission) and upregulated the fission-related proteins FIS1 and DRP1. Collectively, our results demonstrate that siRNA-mediated TWIST1 knockdown induces mitochondrial dysfunction and enhances IR- and ATO-induced cell death in lung cancer cells.

  5. Binational Arsenic Exposure Survey: Methodology and Estimated Arsenic Intake from Drinking Water and Urinary Arsenic Concentrations

    OpenAIRE

    Harris, Robin B.; Burgess, Jefferey L; Maria Mercedes Meza-Montenegro; Luis Enrique Gutiérrez-Millán; Mary Kay O’Rourke; Jason Roberge

    2012-01-01

    The Binational Arsenic Exposure Survey (BAsES) was designed to evaluate probable arsenic exposures in selected areas of southern Arizona and northern Mexico, two regions with known elevated levels of arsenic in groundwater reserves. This paper describes the methodology of BAsES and the relationship between estimated arsenic intake from beverages and arsenic output in urine. Households from eight communities were selected for their varying groundwater arsenic concentrations in Arizona, USA and...

  6. Genomically amplified Akt3 activates DNA repair pathway and promotes glioma progression.

    Science.gov (United States)

    Turner, Kristen M; Sun, Youting; Ji, Ping; Granberg, Kirsi J; Bernard, Brady; Hu, Limei; Cogdell, David E; Zhou, Xinhui; Yli-Harja, Olli; Nykter, Matti; Shmulevich, Ilya; Yung, W K Alfred; Fuller, Gregory N; Zhang, Wei

    2015-03-17

    Akt is a robust oncogene that plays key roles in the development and progression of many cancers, including glioma. We evaluated the differential propensities of the Akt isoforms toward progression in the well-characterized RCAS/Ntv-a mouse model of PDGFB-driven low grade glioma. A constitutively active myristoylated form of Akt1 did not induce high-grade glioma (HGG). In stark contrast, Akt2 and Akt3 showed strong progression potential with 78% and 97% of tumors diagnosed as HGG, respectively. We further revealed that significant variations in polarity and hydropathy values among the Akt isoforms in both the pleckstrin homology domain (P domain) and regulatory domain (R domain) were critical in mediating glioma progression. Gene expression profiles from representative Akt-derived tumors indicated dominant and distinct roles for Akt3, consisting primarily of DNA repair pathways. TCGA data from human GBM closely reflected the DNA repair function, as Akt3 was significantly correlated with a 76-gene signature DNA repair panel. Consistently, compared with Akt1 and Akt2 overexpression models, Akt3-expressing human GBM cells had enhanced activation of DNA repair proteins, leading to increased DNA repair and subsequent resistance to radiation and temozolomide. Given the wide range of Akt3-amplified cancers, Akt3 may represent a key resistance factor.

  7. Matriptase promotes inflammatory cell accumulation and progression of established epidermal tumors

    DEFF Research Database (Denmark)

    Sales, K U; Friis, S; Abusleme, L

    2015-01-01

    Deregulation of matriptase is a consistent feature of human epithelial cancers and correlates with poor disease outcome. We have previously shown that matriptase promotes multi-stage squamous cell carcinogenesis in transgenic mice through dual activation of pro-hepatocyte growth factor-cMet-Akt-m......Deregulation of matriptase is a consistent feature of human epithelial cancers and correlates with poor disease outcome. We have previously shown that matriptase promotes multi-stage squamous cell carcinogenesis in transgenic mice through dual activation of pro-hepatocyte growth factor...

  8. Arsenic and chromium in drinking water promote tumorigenesis in a mouse colitis-associated colorectal cancer model and the potential mechanism is ROS-mediated Wnt/β-catenin signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xin; Mandal, Ardhendu K. [Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536 (United States); Saito, Hiroshi [Department of Surgery and Physiology, Lucille P. Markey Cancer Center, University of Kentucky, Lexington, KY 40536 (United States); Pulliam, Joseph F.; Lee, Eun Y. [Pathology and Laboratory Medicine, University of Kentucky, Lexington, KY 40536 (United States); Ke, Zun-Ji; Lu, Jian; Ding, Songze [Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536 (United States); Li, Li [Department of Family Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Shelton, Brent J.; Tucker, Thomas [Markey Cancer Control Program, University of Kentucky, Lexington, KY 40504 (United States); Evers, B. Mark [Department of Surgery and Physiology, Lucille P. Markey Cancer Center, University of Kentucky, Lexington, KY 40536 (United States); Zhang, Zhuo [Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536 (United States); Shi, Xianglin, E-mail: xshi5@uky.edu [Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536 (United States)

    2012-07-01

    Exposure to carcinogenic metals, such as trivalent arsenic [As(III)] and hexavalent chromium [Cr(VI)], through drinking water is a major global public health problem and is associated with various cancers. However, the mechanism of their carcinogenicity remains unclear. In this study, we used azoxymethane/dextran sodium sulfate (AOM/DSS)-induced mouse colitis-associated colorectal cancer model to investigate their tumorigenesis. Our results demonstrate that exposure to As(III) or Cr(VI), alone or in combination, together with AOM/DSS pretreatment has a promotion effect, increasing the colorectal tumor incidence, multiplicity, size, and grade, as well as cell inflammatory response. Two-dimensional differential gel electrophoresis coupled with mass spectrometry revealed that As(III) or Cr(VI) treatment alone significantly changed the density of proteins. The expression of β-catenin and phospho-GSK was increased by treatment of carcinogenic metals alone. Concomitantly, the expression of NADPH oxidase1 (NOX1) and the level of 8-OHdG were also increased by treatment of carcinogenic metals alone. Antioxidant enzymes, such as superoxide dismutase (SOD) and catalase, were decreased. Similarly, in an in vitro system, exposure of CRL-1807 to carcinogenic metals increased reactive oxygen species (ROS) generation, the expression of β-catenin, phospho-GSK, and NOX1. Inhibition of ROS generation by addition of SOD or catalase inhibited β-catenin expression and activity. Our study provides a new animal model to study the carcinogenicity of As(III) and Cr(VI) and suggests that As(III) and Cr(VI) promote colorectal cancer tumorigenesis, at least partly, through ROS-mediated Wnt/β-catenin signaling pathway. -- Highlights: ► Carcinogenic metals in drinking water promote colorectal tumor formation in vivo. ► Carcinogenic metals induce β-catenin activation in vivo and in vitro. ► ROS generation induced by carcinogenic metals mediated β-catenin activation.

  9. Inhibitory mechanism of dimercaptopropanesulfonic acid (DMPS) in the cellular biomethylation of arsenic.

    Science.gov (United States)

    Wang, Shuping; Shi, Nan; Geng, Zhirong; Li, Xiangli; Hu, Xin; Wang, Zhilin

    2014-11-01

    Dimercaptopropanesulfonic acid (DMPS) has been approved for the treatment of arsenic poisoning through promoting arsenic excretion and modulating arsenic species. To clarify how DMPS regulates the excretion of arsenic species, we investigated the effects of DMPS on the biomethylation of arsenite (As(3+)) in HepG2 cells. In the experiments, we found that DMPS at low concentrations dramatically decreased the content of arsenic in HepG2 cells and inhibited the cellular methylation of As(3+). Three aspects, the expression of human arsenic (III) methyltransferase (hAS3MT), the accumulation of cellular reactive oxygen species (ROS) and the in vitro enzymatic methylation of arsenic, were considered to explain the reasons for the inhibition of DMPS in arsenic metabolism. The results suggested that DMPS competitively coordinated with As(3+) and monomethylarsonous acid (MMA(3+)) to inhibit the up-regulation of arsenic on the expression of hAS3MT and block arsenic involving in the enzymatic methylation. Moreover, DMPS eliminated arsenic-induced accumulation of ROS, which might contribute to the antidotal effects of DMPS on arsenic posing.

  10. Dissolution of Arsenic Minerals Mediated by Dissimilatory Arsenate Reducing Bacteria: Estimation of the Physiological Potential for Arsenic Mobilization

    Directory of Open Access Journals (Sweden)

    Drewniak Lukasz

    2014-01-01

    Full Text Available The aim of this study was characterization of the isolated dissimilatory arsenate reducing bacteria in the context of their potential for arsenic removal from primary arsenic minerals through reductive dissolution. Four strains, Shewanella sp. OM1, Pseudomonas sp. OM2, Aeromonas sp. OM4, and Serratia sp. OM17, capable of anaerobic growth with As (V reduction, were isolated from microbial mats from an ancient gold mine. All of the isolated strains: (i produced siderophores that promote dissolution of minerals, (ii were resistant to dissolved arsenic compounds, (iii were able to use the dissolved arsenates as the terminal electron acceptor, and (iii were able to use copper minerals containing arsenic minerals (e.g., enargite as a respiratory substrate. Based on the results obtained in this study, we postulate that arsenic can be released from some As-bearing polymetallic minerals (such as copper ore concentrates or middlings under reductive conditions by dissimilatory arsenate reducers in indirect processes.

  11. Homocysteine Is an Oncometabolite in Breast Cancer, Which Promotes Tumor Progression and Metastasis

    Science.gov (United States)

    2014-09-01

    diseases and also a pregnancy disorder known as preeclampsia. Polymorphisms in MTHFR that decrease the catalytic activity of the enzyme are common in the...low. Therefore, the nutritional status of individuals in terms of these three vitamins will also have an impact on the growth, progression, and...patients to take vitamin supplements to improve their nutritional status of folic acid, vitamin B12, and pyridoxine so as to reduce the homocysteine

  12. HnRNP-L promotes prostate cancer progression by enhancing cell cycling and inhibiting apoptosis.

    Science.gov (United States)

    Zhou, Xumin; Li, Qi; He, Jincan; Zhong, Liren; Shu, Fangpeng; Xing, Rongwei; Lv, Daojun; Lei, Bin; Wan, Bo; Yang, Yu; Wu, Huayan; Mao, Xiangming; Zou, Yaguang

    2016-12-27

    Expression of the RNA-binding protein HnRNP-L was previously shown to associate with tumorigenesis in liver and lung cancer. In this study, we examined the role of HnRNP-L in prostate cancer (Pca). We found that HnRNP-L is overexpressed in prostate tissue samples from 160 PC patients compared with tissue samples from 32 donors with cancers other than Pca. Moreover, HnRNP-L positively correlated with aggressive tumor characteristics. HnRNP-L knockdown inhibited cell proliferation and promoted cell apoptosis of Pca cell lines in vitro, and suppressed tumor growth when the cells were subcutaneously implanted in an athymic mouse model. Conversely, overexpression of HnRNP-L promoted cell proliferation and tumor growth while prohibiting cell apoptosis. HnRNP-L promoted cell proliferation and tumor growth in Pca in part by interacting with endogenous p53 mRNA, which was closely associated with cyclin p21. In addition, HnRNP-L affected cell apoptosis by directly binding the classical apoptosis protein BCL-2. These observations suggest HnRNP-L is an important regulatory factor that exerts pro-proliferation and anti-apoptosis effects in Pca through actions affecting the cell cycle and intrinsic apoptotic signaling. Thus HnRNP-L could potentially serve as a valuable molecular biomarker or therapeutic target in the treatment of Pca.

  13. Arsenic poisoning in cattle

    Energy Technology Data Exchange (ETDEWEB)

    Reagor, J.C.

    Reports of heavy metal intoxication submitted to the Texas Veterinary Medical Diagnostic Laboratory indicate that arsenic is the most common heavy metal intoxicant in Texas. The most frequent sources of arsenic are compounds used as herbicides and cotton defoliants. The misuse of these compounds and subsequent intoxication of cattle is discussed in this paper. 8 references, 1 table.

  14. [Acute arsenic poisoning].

    Science.gov (United States)

    Montelescaut, Etienne; Vermeersch, Véronique; Commandeur, Diane; Huynh, Sophie; Danguy des Deserts, Marc; Sapin, Jeanne; Ould-Ahmed, Mehdi; Drouillard, Isabelle

    2014-01-01

    Acute arsenic poisoning is a rare cause of suicide attempt. It causes a multiple organs failure caused by cardiogenic shock. We report the case of a patient admitted twelve hours after an ingestion of trioxide arsenic having survived thanks to a premature treatment.

  15. Circulating low IL-23: IL-35 cytokine ratio promotes progression associated with poor prognosisin breast cancer.

    Science.gov (United States)

    Chen, Guanghui; Liang, Yanfang; Guan, Xin; Chen, Hui; Liu, Qiankun; Lin, Bihua; Chen, Can; Huang, Mingyuan; Chen, Jianan; Wu, Weiquan; Liang, Yi; Zhou, Keyuan; Zeng, Jincheng

    2016-01-01

    The interleukin (IL)-12 family, composed of heterodimeric cytokines including IL-12 (formed by IL-12p35 and IL-12p40 subunits), IL-23 (formed by IL-23p19 and IL-12p40 subunits), IL-27 (formed by IL-27p28 and EBI3 subunits) and IL-35 (formed by IL-12p35 and EBI3 subunits), establishes a link between innate and adaptive immunity that involves different immune effector cells and cytokines to tumors. However, the role of IL-12 family in breast cancer (BC) progression and prognosis remains unclear. In the present study, we demonstrated evidence indicating that EBI3, IL-12p35 and IL-12p40 but not IL-23p19 or IL-27p28 were highly expressed in BC tissues, suggested that tumor derived EBI3, IL-12p35 and IL-12p40 were associated with tumor progression. Circulating IL-12 and IL-23 low expressed, but IL-27 and IL-35 high expressed in BC patients, especially circulating IL-23 associated with IL-35 to mediate BC tumor resection. Ki-67, p53 and EGFR expression on BC tissues, as well as CA125, CA153 and CA199 levels on BC bloods increased when circulating IL-23: IL-35 ratio decreased. Together, for the first time, our data suggest that circulating IL-23: IL-35 ratio may be an important indicator association with BC progression and prognosis. However, further research should be carried out to assess the implications of circulating IL-23: IL-35 ratio in a larger sample size.

  16. Interleukin-6 Gene Promoter-572 C Allele May Play a Role in Rate of Disease Progression in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Judith M. Greer

    2012-10-01

    Full Text Available Multiple sclerosis (MS is an inflammatory demyelinating disease affecting the central nervous system. Although the exact pathogenesis of MS is unknown, it is generally considered to be an autoimmune disease, with numerous genetic and environmental factors determining disease susceptibility and severity. One important mediator of immune responses and inflammation is interleukin-6 (IL-6. Previously, elevated levels of IL-6 in mononuclear cells in blood and in brain tissue from MS patients have been reported. Various polymorphisms in the promoter region of the IL6 gene have also been linked with IL-6 protein levels. In MS, several small studies have investigated whether two IL6 promoter polymorphisms (−597 G>A and −174 G>C correlate with MS susceptibility, but with varying results. In the present study, we analyzed these polymorphisms, together with an additional polymorphism (−572 G>C in 279 healthy controls and 509 patients with MS. We found no significant differences between MS patients and healthy controls for the different −597 or −174 IL6 promoter alleles or genotypes. There was a slight reduction in the percentage of individuals with MS who carried a C allele at position −572, although this was not significant after correction for multiple comparisons. Interestingly, however, the −572 C allele showed a significant correlation with the MS severity score, suggesting a possible role in disease progression.

  17. Nuclear vasohibin-2 promotes cell proliferation by inducing G0/G1 to S phase progression.

    Science.gov (United States)

    Ge, Qianqian; Zhou, Jia; Tu, Min; Xue, Xiaofeng; Li, Zhanjun; Lu, Zipeng; Wei, Jishu; Song, Guoxin; Chen, Jianmin; Guo, Feng; Jiang, Kuirong; Miao, Yi; Gao, Wentao

    2015-09-01

    As a member of the vasohibin (VASH2) family, VASH2 is localized intracellularly as a nuclear and cytoplasmic type. Cytoplasmic VASH2 is associated with carcinoma angiogenesis and malignant transformation and promotes cancer growth. However, the function of nuclear VASH2 has yet to be investigated. The aim of the present study was to detect the nuclear VASH2 expression profile in human organs and tissues by protein microarray technique. To examine the function of nuclear VASH2, we analyzed the relationship between nuclear VASH2 and Ki-67, and stably constructed VASH2 overexpression and knockdown in LO2 and HepG2 cell lines, based on a previous study in hepatic cells. The study was conducted using bromodeoxyuridine, immunofluorescent staining, western blot analysis and flow cytometry. Nuclear VASH2 was highly expressed in actively dividing cells in normal and cancer tissues. There was a significant positive correlation between nuclear VASH2 and Ki-67, indicating that nuclear VASH2 positively correlated with cell proliferation in normal and cancer tissues. The bromodeoxyuridine (BrdU) proliferation test showed that nuclear VASH2 increased the S-phase population and promoted cell proliferation, while VASH2 knockdown reduced BrdU absorbance. Cell cycle analysis revealed that nuclear VASH2 overexpression increased the S-phase population in LO2 and HepG2 cells, while nuclear VASH2 knockdown reduced the S-phase population and increased the G0/G1 population. The findings of this study challenge the classic view of VASH2, which was previously reported as an angiogenesis factor. Furthermore, to the best of our knowledge, these results are the first clinical data indicating that nuclear VASH2, but not cytoplasmic VASH2, promotes cell proliferation by driving the cell cycle from the G0/G1 to S phase.

  18. Developing sense of coherence in educational contexts: making progress in promoting mental health in children.

    Science.gov (United States)

    Krause, Christina

    2011-12-01

    The notion of salutogenesis was developed by Aaron Antonovsky to achieve a fundamental innovative approach to promoting mental health. Within the concept of salutogenesis, the author defined the sense of coherence (SOC) as a global life orientation, and he suggests that it emerges in the early years of childhood. In order to develop coherence and its components it is necessary to explore certain health resources. In this paper the following questions will be discussed: (1) which are the individual and social resources to keep healthy, and (2) how can these resources be activated? Selected empirical findings will be presented to respond to these research questions. The results show that resources such as self-worth and a sense of belonging are fundamental health factors. They can be developed most effectively in the early years of childhood and through the formal educational system, e.g. in kindergartens and primary schools. However, the findings show that professionals need to be trained to be able to deliver educational programmes in terms of salutogenesis. At the same time, experience shows that promoting health resources in children successfully depends on the participation of the parents and their support by the professional educators. This paper aims to present new ideas and experiences in the area of a practical realization of the concept of salutogenesis in educational systems. Particularly, health promotion programmes, for example 'The I am I programme' ( Krause, 2009 ), could be implemented successfully in kindergartens with a high quota of children with an immigrant background, due to the fact that this programme includes the reflection and experience of cultural traditions, food, songs, dancing, and family rituals.

  19. Radiation Promotes Colorectal Cancer Initiation and Progression by Inducing Senescence-Associated Inflammatory Responses

    Science.gov (United States)

    Kim, Sang Bum; Bozeman, Ronald; Kaisani, Aadil; Kim, Wanil; Zhang, Lu; Richardson, James A.; Wright, Woodring E.; Shay, Jerry W.

    2015-01-01

    Proton radiotherapy is becoming more common since protons induce more precise DNA damage at the tumor site with reduced side effects to adjacent normal tissues. However, the long-term biological effects of proton irradiation in cancer initiation compared to conventional photon irradiation are poorly characterized. In this study, using a human familial adenomatous polyposis syndrome susceptible mouse model, we show that whole body irradiation with protons are more effective in inducing senescence-associated inflammatory responses (SIR) which are involved in colon cancer initiation and progression. After proton irradiation, a subset of SIR genes (Troy, Sox17, Opg, Faim2, Lpo, Tlr2 and Ptges) and a gene known to be involved in invasiveness (Plat), along with the senescence associated gene (P19Arf) are markedly increased. Following these changes loss of Casein kinase Iα (CKIα) and induction of chronic DNA damage and TP53 mutations are increased compared to x-ray irradiation. Proton irradiation also increases the number of colonic polyps, carcinomas and invasive adenocarcinomas. Pretreatment with the non-steroidal anti-inflammatory drug, CDDO-EA, reduces proton irradiation associated SIR and tumorigenesis. Thus, exposure to proton irradiation elicits significant changes in colorectal cancer initiation and progression that can be mitigated using CDDO-EA. PMID:26477319

  20. High KRT8 expression promotes tumor progression and metastasis of gastric cancer.

    Science.gov (United States)

    Fang, Jian; Wang, Hao; Liu, Yun; Ding, Fangfang; Ni, Ying; Shao, Shihe

    2017-02-01

    Keratin8 (KRT8) is the major component of the intermediate filament cytoskeleton and predominantly expressed in simple epithelial tissues. Aberrant expression of KRT8 is associated with multiple tumor progression and metastasis. However, the role of KRT8 in gastric cancer (GC) remains unclear. In this study, KRT8 expression was investigated and it was found to be upregulated along with human GC progression and metastasis at both mRNA and protein levels in human gastric cancer tissues. In addition, KRT8 overexpression enhanced the proliferation and migration of human gastric cancer cells, whereas the knock-down of KRT8 by siRNA only inhibited migration of human gastric cancer cells. Integrinβ1-FAK-induced epithelial-mesenchymal-transition (EMT) only existed in the high KRT8 cells. Furthermore, KRT8 overexpression led to increase in p-smad2/3 levels and TGFβ dependent signaling events. KRT8 expression in GC was related to tumor clinical stage and worse survival. Kaplan-Meier analysis proved that KRT8 was associated with overall survival of patients with GC that patients with high KRT8 expression tend to have unfavorable outcome. Moreover, Cox's proportional hazards analysis showed that high KRT8 expression was a prognostic marker of poor outcome. These results provided that KRT8 expression may therefore be a biomarker or potential therapeutic target to identify patients with worse survival.

  1. MMSET is dynamically regulated during cell-cycle progression and promotes normal DNA replication.

    Science.gov (United States)

    Evans, Debra L; Zhang, Haoxing; Ham, Hyoungjun; Pei, Huadong; Lee, SeungBaek; Kim, JungJin; Billadeau, Daniel D; Lou, Zhenkun

    2016-01-01

    The timely and precise duplication of cellular DNA is essential for maintaining genome integrity and is thus tightly-regulated. During mitosis and G1, the Origin Recognition Complex (ORC) binds to future replication origins, coordinating with multiple factors to load the minichromosome maintenance (MCM) complex onto future replication origins as part of the pre-replication complex (pre-RC). The pre-RC machinery, in turn, remains inactive until the subsequent S phase when it is required for replication fork formation, thereby initiating DNA replication. Multiple myeloma SET domain-containing protein (MMSET, a.k.a. WHSC1, NSD2) is a histone methyltransferase that is frequently overexpressed in aggressive cancers and is essential for normal human development. Several studies have suggested a role for MMSET in cell-cycle regulation; however, whether MMSET is itself regulated during cell-cycle progression has not been examined. In this study, we report that MMSET is degraded during S phase in a cullin-ring ligase 4-Cdt2 (CRL4(Cdt2)) and proteasome-dependent manner. Notably, we also report defects in DNA replication and a decreased association of pre-RC factors with chromatin in MMSET-depleted cells. Taken together, our results suggest a dynamic regulation of MMSET levels throughout the cell cycle, and further characterize the role of MMSET in DNA replication and cell-cycle progression.

  2. Altered Fibroblast Growth Factor Receptor 4 Stability Promotes Prostate Cancer Progression

    Directory of Open Access Journals (Sweden)

    Jianghua Wang

    2008-08-01

    Full Text Available Fibroblast growth factor receptor 4 (FGFR-4 is expressed at significant levels in almost all human prostate cancers, and expression of its ligands is ubiquitous. A common polymorphism of FGFR-4 in which arginine (Arg388 replaces glycine (Gly388 at amino acid 388 is associated with progression in human prostate cancer. We show that the FGFR-4 Arg388 polymorphism, which is present in most prostate cancer patients, results in increased receptor stability and sustained receptor activation. In patients bearing the FGFR-4 Gly388 variant, expression of Huntingtin-interacting protein 1 (HIP1, which occurs in more than half of human prostate cancers, also results in FGFR-4 stabilization. This is associated with enhanced proliferation and anchorage-independent growth in vitro. Our findings indicate that increased receptor stability and sustained FGFR-4 signaling occur in most human prostate cancers due to either the presence of a common genetic polymorphism or the expression of a protein that stabilizes FGFR-4. Both of these alterations are associated with clinical progression in patients with prostate cancer. Thus, FGFR-4 signaling and receptor turnover are important potential therapeutic targets in prostate cancer.

  3. The adhesion molecule NCAM promotes ovarian cancer progression via FGFR signalling

    DEFF Research Database (Denmark)

    Zecchini, Silvia; Bombardelli, Lorenzo; Decio, Alessandra;

    2011-01-01

    stimulates EOC cell migration and invasion in vitro and promotes metastatic dissemination in mice. This pro-malignant function of NCAM is mediated by its interaction with fibroblast growth factor receptor (FGFR). Indeed, not only FGFR signalling is required for NCAM-induced EOC cell motility, but targeting...... the NCAM/FGFR interplay with a monoclonal antibody abolishes the metastatic dissemination of EOC in mice. Our results point to NCAM-mediated stimulation of FGFR as a novel mechanism underlying EOC malignancy and indicate that this interplay may represent a valuable therapeutic target....

  4. Aberrant hypomethylation-mediated CD147 overexpression promotes aggressive tumor progression in human prostate cancer.

    Science.gov (United States)

    Liang, Yu-Xiang; Mo, Ru-Jun; He, Hui-Chan; Chen, Jia-Hong; Zou, Jun; Han, Zhao-Dong; Lu, Jian-Ming; Cai, Chao; Zeng, Yan-Ru; Zhong, Wei-De; Wu, Chin-Lee

    2015-05-01

    Our previous study revealed the potential role of CD147 in human prostate cancer (PCa). Here, we investigated the CD147 promoter methylation status and the correlation with tumorigenicity in human PCa. CD147 mRNA and protein expression levels were both significantly higher in the 4 PCa cell lines, than in the 2 non-tumorigenic benign human prostatic epithelial cell lines (all PCD147 in PCa cell lines with significant CD147 expression as compared to non-tumorigenic benign human prostatic epithelial cell lines slowly expressing CD147. Additionally, the treatment of methylated cell lines with 5-aza-2'-deoxycytidine increased CD147 expression significantly in low-expressing cell lines and also activated the expression of matrix metalloproteinase (MMP)-2, which may be one of the most important downstream targets of CD147. Furthermore, PCa tissues displayed decreased DNA methylation in the promoter region of CD147 compared to the corresponding non-cancerous prostate tissues, and methylation intensity correlated inversely with the CD147 mRNA levels. There was a significant negative correlation between CD147 mRNA levels and the number of methylated sites in PCa tissues (r=-0.467, PCD147 may be one of the regulatory mechanisms involved in the cancer-related overexpression of CD147 and may play a crucial role in the tumorigenesis of PCa.

  5. Early Epigenetic Downregulation of microRNA-192 Expression Promotes Pancreatic Cancer Progression.

    Science.gov (United States)

    Botla, Sandeep K; Savant, Soniya; Jandaghi, Pouria; Bauer, Andrea S; Mücke, Oliver; Moskalev, Evgeny A; Neoptolemos, John P; Costello, Eithne; Greenhalf, William; Scarpa, Aldo; Gaida, Matthias M; Büchler, Markus W; Strobel, Oliver; Hackert, Thilo; Giese, Nathalia A; Augustin, Hellmut G; Hoheisel, Jörg D

    2016-07-15

    Pancreatic ductal adenocarcinoma (PDAC) is characterized by very early metastasis, suggesting the hypothesis that metastasis-associated changes may occur prior to actual tumor formation. In this study, we identified miR-192 as an epigenetically regulated suppressor gene with predictive value in this disease. miR-192 was downregulated by promoter methylation in both PDAC and chronic pancreatitis, the latter of which is a major risk factor for the development of PDAC. Functional studies in vitro and in vivo in mouse models of PDAC showed that overexpression of miR-192 was sufficient to reduce cell proliferation and invasion. Mechanistic analyses correlated changes in miR-192 promoter methylation and expression with epithelial-mesenchymal transition. Cell proliferation and invasion were linked to altered expression of the miR-192 target gene SERPINE1 that is encoding the protein plasminogen activator inhibitor-1 (PAI-1), an established regulator of these properties in PDAC cells. Notably, our data suggested that invasive capacity was altered even before neoplastic transformation occurred, as triggered by miR-192 downregulation. Overall, our results highlighted a role for miR-192 in explaining the early metastatic behavior of PDAC and suggested its relevance as a target to develop for early diagnostics and therapy. Cancer Res; 76(14); 4149-59. ©2016 AACR.

  6. Prevention and health promotion: decades of progress, new challenges, and an emerging agenda.

    Science.gov (United States)

    Smith, Timothy W; Orleans, C Tracy; Jenkins, C David

    2004-03-01

    Daily habits (e.g., smoking, diet, and exercise) and their immediate consequences (e.g., obesity) confer risk for most of the major health problems in industrialized nations. Hence, determinants of these behaviors and their modifications have been central topics in health psychology. Considerable scientific and applied progress has been made, but the field faces important challenges and opportunities in the future. These challenges and opportunities include changes in demographics and patterns of health, the need for a more comprehensive model of the domain of health behavior and prevention, the need to integrate behavioral and psychosocial risk and resilience, the incorporation of new technologies, and addressing a variety of professional and economic barriers to the implementation of prevention in health care.

  7. Interleukin-33 promotes disease progression in patients with primary biliary cirrhosis.

    Science.gov (United States)

    Sun, Yongqiang; Zhang, Ji-Yuan; Lv, Sa; Wang, Huan; Gong, Man; Du, Ning; Liu, Honghong; Zhang, Ning; Jing, Jing; Zhou, Chao; Zhang, Fan; Wang, Zongren

    2014-01-01

    Primary biliary cirrhosis (PBC) is a progressive autoimmune liver disease that can cause a series of complications, including cirrhosis, liver failure and hepatocellular carcinoma. Interleukin-33 (IL-33) is expressed in various non-hematopoietic cells and a certain population of immune cells, and exerts its biological effects by binding to the specific receptor, suppression of tumorigenicity 2 (ST2). A soluble form of ST2 (sST2) has been postulated to act as a decoy receptor for IL-33. In this study, we aimed to investigate the role of IL-33 in the pathogenesis of PBC. The study included 20 healthy controls and 68 patients with PBC. We thus found the increased serum IL-33 levels in PBC patients. Its elevated levels were positively correlated with serum alkaline phosphatase levels (a key parameter for the definition of PBC) and with Child-Pugh scores, which were used to determine the prognosis of liver cirrhosis. Moreover, the serum concentrations of sST2 were significantly higher in PBC patients compared with healthy subjects, irrespective of the disease severity. Importantly, the cells that express IL-33 and/or myeloperoxidase (a marker for neutrophils) were accumulated in the livers of PBC patients, and their number increased with the severity of liver lesions. Lastly, in vitro chemotaxis assays revealed that IL-33 enhanced the migration of neutrophils. These data suggest that IL-33 may affect the progress of PBC by recruiting neutrophils to the liver. This expanded knowledge of IL-33 in PBC patients is important for developing therapeutic strategies (e.g., neutralization of IL-33), selecting optimal clinical management, and predicting prognosis.

  8. Innovative business approaches for incenting health promotion in sub-Saharan Africa: progress and persisting challenges.

    Science.gov (United States)

    Patel, Deepak N; Nossel, Craig; Alexander, Eleanore; Yach, Derek

    2013-01-01

    Non-communicable chronic diseases related to behaviors such as tobacco use, overeating, excess alcohol intake and physical inactivity account for increasing morbidity and mortality in South Africa. Over the last 15 years, Discovery Health, the largest private health plan in South Africa, has developed a voluntary health promotion program called Vitality with over 1.5 million members. Vitality was designed with many applications drawn from the growing field of behavioral economics, including the use of incentives and rewards. Incentives offered on the program are aimed at lowering the financial barriers to activities such as visiting the gym, buying healthy food or receiving preventive screening. Members accrue points for engagement which translate into discounts on a range of goods and services. Although the full impact of the program cannot yet be quantified, engagement with the program is continually increasing and there is compelling evidence that this translates into better health and cost outcomes.

  9. ANGPTL4 deficiency in haematopoietic cells promotes monocyte expansion and atherosclerosis progression

    Science.gov (United States)

    Aryal, Binod; Rotllan, Noemi; Araldi, Elisa; Ramírez, Cristina M.; He, Shun; Chousterman, Benjamin G.; Fenn, Ashley M.; Wanschel, Amarylis; Madrigal-Matute, Julio; Warrier, Nikhil; Martín-Ventura, Jose L.; Swirski, Filip K.; Suárez, Yajaira; Fernández-Hernando, Carlos

    2016-07-01

    Lipid accumulation in macrophages has profound effects on macrophage gene expression and contributes to the development of atherosclerosis. Here, we report that angiopoietin-like protein 4 (ANGPTL4) is the most highly upregulated gene in foamy macrophages and it's absence in haematopoietic cells results in larger atherosclerotic plaques, characterized by bigger necrotic core areas and increased macrophage apoptosis. Furthermore, hyperlipidemic mice deficient in haematopoietic ANGPTL4 have higher blood leukocyte counts, which is associated with an increase in the common myeloid progenitor (CMP) population. ANGPTL4-deficient CMPs have higher lipid raft content, are more proliferative and less apoptotic compared with the wild-type (WT) CMPs. Finally, we observe that ANGPTL4 deficiency in macrophages promotes foam cell formation by enhancing CD36 expression and reducing ABCA1 localization in the cell surface. Altogether, these findings demonstrate that haematopoietic ANGPTL4 deficiency increases atherogenesis through regulating myeloid progenitor cell expansion and differentiation, foam cell formation and vascular inflammation.

  10. Overexpression of Long Non-Coding RNA TUG1 Promotes Colon Cancer Progression

    Science.gov (United States)

    Zhai, Hui-yuan; Sui, Ming-hua; Yu, Xiao; Qu, Zhen; Hu, Jin-chen; Sun, Hai-qing; Zheng, Hai-tao; Zhou, Kai; Jiang, Li-xin

    2016-01-01

    Background Colon cancer is one of the most prevalent and deadly cancers worldwide. It is still necessary to further define the mechanisms and explore therapeutic targets of colon cancer. Dysregulation of long noncoding RNAs (lncRNAs) has been shown to be correlated with diverse biological processes, including tumorigenesis. This study aimed to characterize the biological mechanism of taurine-upregulated gene 1 (TUG1) in colon cancer. Material/Methods qRT-PCR was used to analyze the expression level of TUG1 and p63 in 75 colon cancer tissues and the matched adjacent non-tumor tissue. In vitro, cultured colon cancer cell lines HCT-116 and LoVo were used as cell models. TUG1 and p63 were silenced via transferring siRNA into HCT-116 or LoVo. The effects of TUG1 were investigated by examining cell proliferation, apoptosis, and migration. Results Among the 75 colon cancer cases, the expression of TUG1 was significantly higher in colon cancer tissues compared with the matched adjacent non-tumor tissue, while p63 expression was lower in the tumor tissue. In HCT-116 and LoVo, the expression of TUG1 was significantly increased by p63 siRNA transfection. Furthermore, down-regulation of TUG1 by siRNA significantly inhibited the cell proliferation and promoted colon cancer cell apoptosis. In addition, inhibition of TUG1 expression significantly blocked the cell migration ability of colon cancer cells. Conclusions LncRNA TUG1 may serve as a potential oncogene for colon cancer. Overexpressed TUG1 may contribute to promoting cell proliferation and migration in colon cancer cells. PMID:27634385

  11. Binational Arsenic Exposure Survey: Methodology and Estimated Arsenic Intake from Drinking Water and Urinary Arsenic Concentrations

    Directory of Open Access Journals (Sweden)

    Robin B. Harris

    2012-03-01

    Full Text Available The Binational Arsenic Exposure Survey (BAsES was designed to evaluate probable arsenic exposures in selected areas of southern Arizona and northern Mexico, two regions with known elevated levels of arsenic in groundwater reserves. This paper describes the methodology of BAsES and the relationship between estimated arsenic intake from beverages and arsenic output in urine. Households from eight communities were selected for their varying groundwater arsenic concentrations in Arizona, USA and Sonora, Mexico. Adults responded to questionnaires and provided dietary information. A first morning urine void and water from all household drinking sources were collected. Associations between urinary arsenic concentration (total, organic, inorganic and estimated level of arsenic consumed from water and other beverages were evaluated through crude associations and by random effects models. Median estimated total arsenic intake from beverages among participants from Arizona communities ranged from 1.7 to 14.1 µg/day compared to 0.6 to 3.4 µg/day among those from Mexico communities. In contrast, median urinary inorganic arsenic concentrations were greatest among participants from Hermosillo, Mexico (6.2 µg/L whereas a high of 2.0 µg/L was found among participants from Ajo, Arizona. Estimated arsenic intake from drinking water was associated with urinary total arsenic concentration (p < 0.001, urinary inorganic arsenic concentration (p < 0.001, and urinary sum of species (p < 0.001. Urinary arsenic concentrations increased between 7% and 12% for each one percent increase in arsenic consumed from drinking water. Variability in arsenic intake from beverages and urinary arsenic output yielded counter intuitive results. Estimated intake of arsenic from all beverages was greatest among Arizonans yet participants in Mexico had higher urinary total and inorganic arsenic concentrations. Other contributors to urinary arsenic concentrations should be evaluated.

  12. Binational arsenic exposure survey: methodology and estimated arsenic intake from drinking water and urinary arsenic concentrations.

    Science.gov (United States)

    Roberge, Jason; O'Rourke, Mary Kay; Meza-Montenegro, Maria Mercedes; Gutiérrez-Millán, Luis Enrique; Burgess, Jefferey L; Harris, Robin B

    2012-04-01

    The Binational Arsenic Exposure Survey (BAsES) was designed to evaluate probable arsenic exposures in selected areas of southern Arizona and northern Mexico, two regions with known elevated levels of arsenic in groundwater reserves. This paper describes the methodology of BAsES and the relationship between estimated arsenic intake from beverages and arsenic output in urine. Households from eight communities were selected for their varying groundwater arsenic concentrations in Arizona, USA and Sonora, Mexico. Adults responded to questionnaires and provided dietary information. A first morning urine void and water from all household drinking sources were collected. Associations between urinary arsenic concentration (total, organic, inorganic) and estimated level of arsenic consumed from water and other beverages were evaluated through crude associations and by random effects models. Median estimated total arsenic intake from beverages among participants from Arizona communities ranged from 1.7 to 14.1 µg/day compared to 0.6 to 3.4 µg/day among those from Mexico communities. In contrast, median urinary inorganic arsenic concentrations were greatest among participants from Hermosillo, Mexico (6.2 µg/L) whereas a high of 2.0 µg/L was found among participants from Ajo, Arizona. Estimated arsenic intake from drinking water was associated with urinary total arsenic concentration (p < 0.001), urinary inorganic arsenic concentration (p < 0.001), and urinary sum of species (p < 0.001). Urinary arsenic concentrations increased between 7% and 12% for each one percent increase in arsenic consumed from drinking water. Variability in arsenic intake from beverages and urinary arsenic output yielded counter intuitive results. Estimated intake of arsenic from all beverages was greatest among Arizonans yet participants in Mexico had higher urinary total and inorganic arsenic concentrations. Other contributors to urinary arsenic concentrations should be evaluated.

  13. KAP1 promotes proliferation and metastatic progression of breast cancer cells.

    Science.gov (United States)

    Addison, Joseph B; Koontz, Colton; Fugett, James H; Creighton, Chad J; Chen, Dongquan; Farrugia, Mark K; Padon, Renata R; Voronkova, Maria A; McLaughlin, Sarah L; Livengood, Ryan H; Lin, Chen-Chung; Ruppert, J Michael; Pugacheva, Elena N; Ivanov, Alexey V

    2015-01-15

    KAP1 (TRIM28) is a transcriptional regulator in embryonic development that controls stem cell self-renewal, chromatin organization, and the DNA damage response, acting as an essential corepressor for KRAB family zinc finger proteins (KRAB-ZNF). To gain insight into the function of this large gene family, we developed an antibody that recognizes the conserved zinc fingers linker region (ZnFL) in multiple KRAB-ZNF. Here, we report that the expression of many KRAB-ZNF along with active SUMOlyated KAP1 is elevated widely in human breast cancers. KAP1 silencing in breast cancer cells reduced proliferation and inhibited the growth and metastasis of tumor xenografts. Conversely, KAP1 overexpression stimulated cell proliferation and tumor growth. In cells where KAP1 was silenced, we identified multiple downregulated genes linked to tumor progression and metastasis, including EREG/epiregulin, PTGS2/COX2, MMP1, MMP2, and CD44, along with downregulation of multiple KRAB-ZNF proteins. KAP1-dependent stabilization of KRAB-ZNF required direct interactions with KAP1. Together, our results show that KAP1-mediated stimulation of multiple KRAB-ZNF contributes to the growth and metastasis of breast cancer.

  14. β-Catenin signaling increases during melanoma progression and promotes tumor cell survival and chemoresistance.

    Directory of Open Access Journals (Sweden)

    Tobias Sinnberg

    Full Text Available Beta-catenin plays an important role in embryogenesis and carcinogenesis by controlling either cadherin-mediated cell adhesion or transcriptional activation of target gene expression. In many types of cancers nuclear translocation of beta-catenin has been observed. Our data indicate that during melanoma progression an increased dependency on the transcriptional function of beta-catenin takes place. Blockade of beta-catenin in metastatic melanoma cell lines efficiently induces apoptosis, inhibits proliferation, migration and invasion in monolayer and 3-dimensional skin reconstructs and decreases chemoresistance. In addition, subcutaneous melanoma growth in SCID mice was almost completely inhibited by an inducible beta-catenin knockdown. In contrast, the survival of benign melanocytes and primary melanoma cell lines was less affected by beta-catenin depletion. However, enhanced expression of beta-catenin in primary melanoma cell lines increased invasive capacity in vitro and tumor growth in the SCID mouse model. These data suggest that beta-catenin is an essential survival factor for metastatic melanoma cells, whereas it is dispensable for the survival of benign melanocytes and primary, non-invasive melanoma cells. Furthermore, beta-catenin increases tumorigenicity of primary melanoma cell lines. The differential requirements for beta-catenin signaling in aggressive melanoma versus benign melanocytic cells make beta-catenin a possible new target in melanoma therapy.

  15. NDRG1 overexpression promotes the progression of esophageal squamous cell carcinoma through modulating Wnt signaling pathway

    Science.gov (United States)

    Ai, Runna; Sun, Yulin; Guo, Zhimin; Wei, Wei; Zhou, Lanping; Liu, Fang; Hendricks, Denver T.; Xu, Yang; Zhao, Xiaohang

    2016-01-01

    ABSTRACT N-myc down-regulated gene 1 (NDRG1) has been shown to regulate tumor growth and metastasis in various malignant tumors and also to be dysregulated in esophageal squamous cell carcinoma (ESCC). Here, we show that NDRG1 overexpression (91.9%, 79/86) in ESCC tumor tissues is associated with poor overall survival of esophageal cancer patients. When placed in stable transfectants of the KYSE 30 ESCC cell line generated by lentiviral transduction with the ectopic overexpression of NDRG1, the expression of transducin-like enhancer of Split 2 (TLE2) was decreased sharply, however β−catenin was increased. Mechanistically, NDRG1 physically associates with TLE2 and β−catenin to affect the Wnt pathway. RNA interference and TLE2 overexpression studies demonstrate that NDRG1 fails to active Wnt pathway compared with isogenic wild-type controls. Strikingly, NDRG1 overexpression induces the epithelial mesenchymal transition (EMT) through activating the Wnt signaling pathway in ESCC cells, decreased the expression of E-cadherin and enhanced the expression of Snail. Our study elucidates a mechanism of NDRG1-regulated Wnt pathway activation and EMT via affecting TLE2 and  β-catenin expression in esophageal cancer cells. This indicates a pro-oncogenic role for NDRG1 in esophageal cancer cells whereby it modulates tumor progression. PMID:27414086

  16. Chemokines and chemokine receptors as promoters of prostate cancer growth and progression.

    Science.gov (United States)

    Salazar, Nicole; Castellan, Miguel; Shirodkar, Samir S; Lokeshwar, Bal L

    2013-01-01

    Prostate cancer (CaP) is estimated to be first in incidence among cancers, with more than 240,000 new cases in 2012 in the United States. Chemokines and their receptors provide survival, proliferation, and invasion characteristics to CaP cells in both primary sites of cancer and metastatic locations. The emerging data demonstrate that many chemokines and their receptors are involved in the multistep process of CaP, leading to metastasis, and, further, that these factors act cooperatively to enhance other mechanisms of tumor cell survival, growth, and metastasis. Changes of chemokine receptor cohorts may be necessary to activate tumor-promoting signals. Chemokine receptors can activate downstream effectors, such as mitogen-activated protein kinases, by complex mechanisms of ligand-dependent activation of cryptic growth factors; guanosine triphosphate-binding, protein-coupled activation of survival kinases; or transactivation of other receptors such as ErbB family members. We describe vanguard research in which more than the classic view of chemokine receptor biology was clarified. Control of chemokines and inhibition of their receptor activation may add critical tools to reduce tumor growth, especially in chemo-hormonal refractory CaP that is both currently incurable and the most aggressive form of the disease, accounting for most of the more than 28,000 annual deaths.

  17. PFTK1 Promotes Gastric Cancer Progression by Regulating Proliferation, Migration and Invasion.

    Science.gov (United States)

    Yang, Lei; Zhu, Jia; Huang, Hua; Yang, Qichang; Cai, Jing; Wang, Qiuhong; Zhu, Junya; Shao, Mengting; Xiao, Jinzhang; Cao, Jie; Gu, Xiaodan; Zhang, Shusen; Wang, Yingying

    2015-01-01

    PFTK1, also known as PFTAIRE1, CDK14, is a novel member of Cdc2-related serine/threonine protein kinases. Recent studies show that PFTK1 is highly expressed in several malignant tumors such as hepatocellular carcinoma, esophageal cancer, breast cancer, and involved in regulation of cell cycle, tumors proliferation, migration, and invasion that further influence the prognosis of tumors. However, the expression and physiological significance of PFTK1 in gastric cancer remain unclear. In this study, we analyzed the expression and clinical significance of PFTK1 by Western blot in 8 paired fresh gastric cancer tissues, nontumorous gastric mucosal tissues and immunohistochemistry on 161 paraffinembedded slices. High PFTK1 expression was correlated with the tumor grade, lymph node invasion as well as Ki-67. Through Cell Counting Kit (CCK)-8 assay, flow cytometry, colony formation, wound healing and transwell assays, the vitro studies demonstrated that PFTK1 overexpression promoted proliferation, migration and invasion of gastric cancer cells, while PFTK1 knockdown led to the opposite results. Our findings for the first time supported that PFTK1 might play an important role in the regulation of gastric cancer proliferation, migration and would provide a novel promising therapeutic strategy against human gastric cancer.

  18. OTX1 promotes colorectal cancer progression through epithelial-mesenchymal transition

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Kun; Cai, Xin-Yi; Li, Qiang; Yang, Zhi-Bin; Xiong, Wei; Shen, Tao; Wang, Wei-Ya; Li, Yun-Feng, E-mail: ynsliyunfeng@163.com

    2014-01-31

    Highlights: • OTX1 is overexpression in colorectal cancer tissues. • Overexpression of OTX1 promotes colorectal cancer cell proliferation and invasion in vitro and tumor growth in vivo. • Depletion of OTX1 inhibits colorectal cancer cell proliferation and invasion in vitro. • Overexpression of OTX1 is linked to the EMT-like phenotype. - Abstract: Orthodenticle homeobox 1 (OTX1), a transcription factor containing a bicoid-like homeodomain, plays a role in brain and sensory organ development. In this study, we report that OTX1 is overexpressed in human colorectal cancer (CRC) and OTX1 overexpression is associated with higher stage. Functional analyses reveal that overexpression of OTX1 results in accumulation of CRC cell proliferation and invasion in vitro and tumor growth in vivo, whereas ablation of OTX1 expression significantly inhibits the proliferative and invasive capability of CRC cells in vitro. Together, our results indicate that OTX1 is involved in human colon carcinogenesis and may serve as a potential therapeutic target for human colorectal cancer.

  19. Structure and regulation of an archaebacterial promoter: An in vivo study. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, C.J.

    1993-12-31

    In the initial grant period the authors have devised an in vivo assay system for the analysis of gene expression in the halophilic archaea. This system has been used to analyzed the H. volcanii tRNALys promoter where it was found that the a 40 bp fragment carrying BoxA and BoxB sequences in sufficient for in vivo expression. Detailed analysis of the BoxA element indicates that the BoxA TA sequence is essential for efficient expression. Support for the hypothesis that all archaea share common transcriptional signals was obtained when a methanogen tRNAGln gene, with its associated BoxA sequence, was found to direct its own transcription in H. volcanii. In related experiments a eukaryotic RNA polymerase 3 terminator was found to act as a strong termination signal in H. volcanii. Sequence comparisons between this element and mapped RNA 3{prime} ends indicates that T-rich sequences may be important role in directing termination in vivo. Finally, in an attempt to establish a model system to study regulated gene expression, the authors have isolated a DNA fragment that encodes a heat shock inaudible transcript. This gene will not serve as a model for detailed studies of the mechanisms of gene expression in the archaea.

  20. A DDB2 mutant protein unable to interact with PCNA promotes cell cycle progression of human transformed embryonic kidney cells.

    Science.gov (United States)

    Perucca, Paola; Sommatis, Sabrina; Mocchi, Roberto; Prosperi, Ennio; Stivala, Lucia Anna; Cazzalini, Ornella

    2015-01-01

    DNA damage binding protein 2 (DDB2) is a protein involved in the early step of DNA damage recognition of the nucleotide excision repair (NER) process. Recently, it has been suggested that DDB2 may play a role in DNA replication, based on its ability to promote cell proliferation. We have previously shown that DDB2 binds PCNA during NER, but also in the absence of DNA damage; however, whether and how this interaction influences cell proliferation is not known. In this study, we have addressed this question by using HEK293 cell clones stably expressing DDB2(Wt) protein, or a mutant form (DDB2(Mut)) unable to interact with PCNA. We report that overexpression of the DDB2(Mut) protein provides a proliferative advantage over the wild type form, by influencing cell cycle progression. In particular, an increase in the number of S-phase cells, together with a reduction in p21(CDKN1A) protein level, and a shorter cell cycle length, has been observed in the DDB2(Mut) cells. These results suggest that DDB2 influences cell cycle progression thanks to its interaction with PCNA.

  1. Metastasis-inducing S100A4 and RANTES cooperate in promoting tumor progression in mice.

    Directory of Open Access Journals (Sweden)

    Birgitte Forst

    Full Text Available BACKGROUND: The tumor microenvironment has been described as a critical milieu determining tumor growth and metastases. A pivotal role of metastasis-inducing S100A4 in the development of tumor stroma has been proven in animal models and verified in human breast cancer biopsies. Expression and release of S100A4 has been shown in various types of stroma composing cells, including fibroblasts and immune cells. However, the events implicated in upstream and downstream pathways regulating the activity of the extracellular S100A4 protein in the tumor milieu remain unsolved. METHODOLOGY/PRINCIPAL FINDINGS: We studied the interplay between the tumor cell-derived cytokine regulated-upon-activation, normal T-cell expressed and secreted (RANTES; CCL5 and S100A4 which were shown to be critical factors in tumor progression. We found that RANTES stimulates the externalization of S100A4 via microparticle shedding from the plasma membrane of tumor and stroma cells. Conversely, the released S100A4 protein induces the upregulation of fibronectin (FN in fibroblasts and a number of cytokines, including RANTES in tumor cells as well as stimulates cell motility in a wound healing assay. Importantly, using wild type and S100A4-deficient mouse models, we demonstrated a substantial influence of tumor cell-derived RANTES on S100A4 release into blood circulation which ultimately increases the metastatic burden in mice. CONCLUSIONS/SIGNIFICANCE: Altogether, the data presented strongly validate the pro-metastatic function of S100A4 in the tumor microenvironment and define how the tumor cell-derived cytokine RANTES acts as a critical regulator of S100A4-dependent tumor cell dissemination. Additionally, for the first time we demonstrated the mechanism of S100A4 release associated with plasma membrane microparticle shedding from various cells types.

  2. Cerebrospinal fluid derived from progressive multiple sclerosis patients promotes neuronal and oligodendroglial differentiation of human neural precursor cells in vitro.

    Science.gov (United States)

    Cristofanilli, M; Cymring, B; Lu, A; Rosenthal, H; Sadiq, S A

    2013-10-10

    In the adult CNS, tissue-specific germinal niches, such as the subventricular zone of the lateral ventricles and the subgranular zone of the dentate gyrus of the hippocampus, contain multipotent neural precursor cells (NPCs) with the capacity to self-renew and differentiate into functional brain cells (i.e. neurons, astrocytes or oligodendrocytes). Due to their intrinsic plasticity, NPCs can be considered an essential part of the cellular mechanism(s) by which the CNS tries to repair itself after an injury. In inflammatory CNS disorders, such as multiple sclerosis (MS), neurogenesis and gliogenesis occur as part of an 'intrinsic' self-repair process. However, full and long-lasting repair in progressive MS is not achieved. Recent data suggest that endogenous NPCs, while trying to repair the damaged CNS in MS, may become the target of the disease itself. It is possible that factors produced during MS, like CNS-infiltrating blood-borne inflammatory mononuclear cells, reactive CNS-resident cells, and humoral mediators, can alter the physiological properties of NPCs, ultimately impairing their ability to promote neural regeneration. Here, we investigate the effect of cerebrospinal fluid (CSF) derived from primary progressive (PPMS) and secondary progressive (SPMS) MS patients (CSF-MS) on the survival, proliferation, and differentiation of commercially available human embryonic-derived NPCs named ENStem-A. We found that PPMS derived CSF markedly reduced the proliferation of ENStem-A and increased their differentiation toward neuronal and oligodendroglial cells, compared to control CSF. Similar but less striking results were seen when ENstem-A were treated with SPMS derived CSF. Our findings suggest that in both SPMS and PPMS the CNS milieu, as determined by extrapolation from CSF findings, may stimulate the endogenous pool of NPCs to differentiate into neurons and oligodendrocytes.

  3. microRNA-206 promotes skeletal muscle regeneration and delays progression of Duchenne muscular dystrophy in mice

    Science.gov (United States)

    Liu, Ning; Williams, Andrew H.; Maxeiner, Johanna M.; Bezprozvannaya, Svetlana; Shelton, John M.; Richardson, James A.; Bassel-Duby, Rhonda; Olson, Eric N.

    2012-01-01

    Skeletal muscle injury activates adult myogenic stem cells, known as satellite cells, to initiate proliferation and differentiation to regenerate new muscle fibers. The skeletal muscle–specific microRNA miR-206 is upregulated in satellite cells following muscle injury, but its role in muscle regeneration has not been defined. Here, we show that miR-206 promotes skeletal muscle regeneration in response to injury. Genetic deletion of miR-206 in mice substantially delayed regeneration induced by cardiotoxin injury. Furthermore, loss of miR-206 accelerated and exacerbated the dystrophic phenotype in a mouse model of Duchenne muscular dystrophy. We found that miR-206 acts to promote satellite cell differentiation and fusion into muscle fibers through suppressing a collection of negative regulators of myogenesis. Our findings reveal an essential role for miR-206 in satellite cell differentiation during skeletal muscle regeneration and indicate that miR-206 slows progression of Duchenne muscular dystrophy. PMID:22546853

  4. Fibroblast growth factor receptor 4 promotes progression and correlates to poor prognosis in cholangiocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yun-Fei [Department of Hepatobiliary Surgery, Qilu Hospital of Shandong University (China); Yang, Xiao-Qing [Department of Pathology, Shandong University (China); Lu, Xiao-Fei [Department of Gastrointestinal Surgery, Jinan Central Hospital (China); Guo, Sen; Liu, Yi; Iqbal, Mohammad; Ning, Shang-Lei; Yang, Hui [Department of Hepatobiliary Surgery, Qilu Hospital of Shandong University (China); Suo, Ning [Department of Anatomy, Shandong University (China); Chen, Yu-Xin, E-mail: yxu8@bidmc.harvard.edu [Department of Hepatobiliary Surgery, Qilu Hospital of Shandong University (China)

    2014-03-28

    Highlights: • FGFR4 is significantly related with N stage in IHCC, with T stage and TNM stage in PHCC. • FGFR4 is an independent prognostic factor in IHCC and PHCC. • FGFR4 promotes proliferation, invasion and EMT in cholangiocarinoma cell lines. • Inhibitor AP24354 can decrease proliferation, invasion and induce apoptosis of CCA. - Abstract: Fibroblast growth factor receptor 4 (FGFR4) is related to poor prognosis of several cancers, but the correlation between FGFR4 expression and cholangiocarcinoma (CCA) has not been well elucidated. We investigated the expression of FGFR4 in 83 intrahepatic cholangiocarcinomas (IHCCs), 75 perihilar cholangiocarcinomas (PHCCs) and 41 distal cholangiocarcinomas (DCCs) by immunohistochemistry (IHC), and subsequently evaluated association of FGFR4 with clinicopathologic parameters and survival rate. The rate of FGFR4 higher expression was 61.4% (51/83) in IHCCs, 53.3% (40/75) in PHCCs and 56.1% (23/41) in DCCs. FGFR4 expression was significantly related to poor prognosis of IHCC (P = 0.002) and PHCC (P = 0.019) with univariate analysis, and also identified as an independent prognostic factor in IHCC (P = 0.045) and PHCC (P = 0.049) with multivariate analysis. Additionally, with functional assays in vitro, we found FGFR4 can induce proliferation, invasion and epithelial–mesenchymal transition (EMT) of CCA cell lines with FGF19 stimulation. Moreover, FGFR4 inhibitor AP24354 can suppress proliferation, invasion and induce apoptosis of CCA cells. In conclusion, FGFR4 expression can be identified as a significant independent prognostic biomarker of IHCC and PHCC. FGFR4 played a pivotal role in proliferation, invasion and EMT of CCA. FGFR4 inhibitor can suppress proliferation, invasion and induce apoptosis of CCA, indicating that FGFR4 may act as a potential therapeutic target.

  5. A biosensor for organoarsenical herbicides and growth promoters

    OpenAIRE

    2014-01-01

    The toxic metalloid arsenic is widely distributed in food, water, and soil. While inorganic arsenic enters the environment primarily from geochemical sources, methylarsenicals either result from microbial biotransformation of inorganic arsenic or are introduced anthropogenically. Methylarsenicals such as monosodium methylarsonic acid (MSMA) have been extensively utilized as herbicides, and aromatic arsenicals such as roxarsone (Rox) are used as growth promoters for poultry and swine. Organoar...

  6. Investigating groundwater arsenic contamination using aquifer push-pull test

    Science.gov (United States)

    Daigle, A. R.; Jin, Q.

    2009-12-01

    The groundwater of the Southern Willamette Basin, OR is contaminated with arsenic at concentrations as high as several ppm. A single-well push-pull test was conducted to investigate how microbial metabolisms control arsenic occurrence and levels in the bedrock aquifer of the area. During the experiments, a test solution containing ethanol was first injected into the aquifer. As the experiment progressed, dissolved gasses, groundwater, and sediment were sampled to monitor the variations in the chemical parameters, including the speciation of iron, sulfur, and arsenic, in the aquifer. Ethanol amendment stimulated a series of microbial metabolisms, including arsenate reduction, iron reduction, and sulfate reduction. Iron reduction released arsenic sorbed onto the aquifer sediments, increasing groundwater arsenic levels. Arsenate reduction converted arsenate to arsenite and, as a result, most arsenic occurred as arsenite in the groundwater. Results of the experiments demonstrate how different microbial functional groups influenced arsenic contamination in the area. These results also shed new light on potential bioremediation strategies in the area.

  7. Association of Promoter Methylation of VGF and PGP9.5 with Ovarian Cancer Progression

    Science.gov (United States)

    Noordhuis, Maartje; Begum, Shahnaz; Loyo, Myriam; Poeta, Maria Luana; Barbosa, Alvaro; Fazio, Vito M.; Angioli, Roberto; Rabitti, Carla; Marchionni, Luigi; de Graeff, Pauline; J. van der Zee, Ate G.; Wisman, G. Bea A.; Sidransky, David; Hoque, Mohammad O.

    2013-01-01

    Purpose To elucidate the role of biological and clinical impact of aberrant promoter hypermethylation (PH) in ovarian cancer (OC). Experimental Design PH of PGP9.5, HIC1, AIM1, APC, PAK3, MGMT, KIF1A, CCNA1, ESR1, SSBP2, GSTP1, FKBP4 and VGF were assessed by quantitative methylation specific PCR (QMSP) in a training set. We selected two genes (VGF and PGP9.5) for further QMSP analysis in a larger independent validation (IV) set with available clinical data. Biologic relevance of VGF gene was also evaluated. Results PH frequency for PGP9.5 and VGF were 85% (316/372) and 43% (158/366) respectively in the IV set of samples while no PH was observed in controls. In 372 OC cases with available follow up, PGP9.5 and VGF PH were correlated with better patient survival [Hazard Ratios (HR) for overall survival (OS) were 0.59 (95% Confidence Intervals (CI)  = 0.42–0.84, p = 0.004), and 0.73 (95%CI = 0.55–0.97, p = 0.028) respectively, and for disease specific survival (DSS) were 0.57 (95%CI 0.39–0.82, p = 0.003) and 0.72 (95%CI 0.54–0.96, p = 0.027). In multivariate analysis, VGF PH remained an independent prognostic factor for OS (HR 0.61, 95%CI 0.43–0.86, p<0.005) and DSS (HR 0.58, 95%CI 0.41–0.83, p<0.003). Furthermore, PGP9.5 PH was significantly correlated with lower grade, early stage tumors, and with absence of residual disease. Forced expression of VGF in OC cell lines inhibited cell growth. Conclusions Our results indicate that VGF and PGP9.5 PH are potential biomarkers for ovarian carcinoma. Confirmatory cohorts with longitudinal follow-up are required in future studies to define the clinical impact of VGF and PGP9.5 PH before clinical application. PMID:24086249

  8. Association of promoter methylation of VGF and PGP9.5 with ovarian cancer progression.

    Directory of Open Access Journals (Sweden)

    Mariana Brait

    Full Text Available PURPOSE: To elucidate the role of biological and clinical impact of aberrant promoter hypermethylation (PH in ovarian cancer (OC. EXPERIMENTAL DESIGN: PH of PGP9.5, HIC1, AIM1, APC, PAK3, MGMT, KIF1A, CCNA1, ESR1, SSBP2, GSTP1, FKBP4 and VGF were assessed by quantitative methylation specific PCR (QMSP in a training set. We selected two genes (VGF and PGP9.5 for further QMSP analysis in a larger independent validation (IV set with available clinical data. Biologic relevance of VGF gene was also evaluated. RESULTS: PH frequency for PGP9.5 and VGF were 85% (316/372 and 43% (158/366 respectively in the IV set of samples while no PH was observed in controls. In 372 OC cases with available follow up, PGP9.5 and VGF PH were correlated with better patient survival [Hazard Ratios (HR for overall survival (OS were 0.59 (95% Confidence Intervals (CI  = 0.42-0.84, p = 0.004, and 0.73 (95%CI = 0.55-0.97, p = 0.028 respectively, and for disease specific survival (DSS were 0.57 (95%CI 0.39-0.82, p = 0.003 and 0.72 (95%CI 0.54-0.96, p = 0.027. In multivariate analysis, VGF PH remained an independent prognostic factor for OS (HR 0.61, 95%CI 0.43-0.86, p<0.005 and DSS (HR 0.58, 95%CI 0.41-0.83, p<0.003. Furthermore, PGP9.5 PH was significantly correlated with lower grade, early stage tumors, and with absence of residual disease. Forced expression of VGF in OC cell lines inhibited cell growth. CONCLUSIONS: Our results indicate that VGF and PGP9.5 PH are potential biomarkers for ovarian carcinoma. Confirmatory cohorts with longitudinal follow-up are required in future studies to define the clinical impact of VGF and PGP9.5 PH before clinical application.

  9. The die is cast - Arsenic exposure in early life and disease susceptibility

    Science.gov (United States)

    Abstract Early life exposure to arsenic in humans and mice produces similar patterns of disease in later life. Given the long interval between exposure and effect, epigenetic effects of early life exposure to arsenic may account for development and progression of disease in bo...

  10. ENZYMOLOGY OF ARSENIC METHYLATION

    Science.gov (United States)

    Enzymology of Arsenic MethylationDavid J. Thomas, Pharmacokinetics Branch, Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park...

  11. Toxic Substances Portal- Arsenic

    Science.gov (United States)

    ... a naturally occurring element widely distributed in the earth's crust. In the environment, arsenic is combined with ... workplace air (10 µg/m 3 ) for 8 hour shifts and 40 hour work weeks. top References ...

  12. EXAFS study on arsenic species and transformation in arsenic hyperaccumulator

    Institute of Scientific and Technical Information of China (English)

    HUANG Zechun; CHEN Tongbin; LEI Mei; HU Tiandou; HUANG Qifei

    2004-01-01

    Synchrotron radiation extended X-ray absorption fine structure (SR EXAFS) was employed to study the transformation of coordination environment and the redox speciation of arsenic in a newly discovered arsenic hyperaccumulator, Cretan brake (Pteris cretica L. var nervosa Thunb). It showed that the arsenic in the plant mainly coordinated with oxygen, except that some arsenic coordinated with S as As-GSH in root. The complexation of arsenic with GSH might not be the predominant detoxification mechanism in Cretan brake. Although some arsenic in root presented as As(V) in Na2HAsO4 treatments, most of arsenic in plant presented as As(III)-O in both treatments, indicating that As(V) tended to be reduced to As(III) after it was taken up into the root, and arsenic was kept as As(III) when it was transported to the above-ground tissues. The reduction of As(V) primarily proceeded in the root.

  13. Thallium and arsenic poisoning in a small midwestern town.

    Science.gov (United States)

    Rusyniak, Daniel E; Furbee, R Brent; Kirk, Mark A

    2002-03-01

    Thallium and arsenic have been used as a means of criminal poisoning. Although both manifest characteristically with peripheral neuropathies, thallium is associated with alopecia and arsenic with gastrointestinal symptoms. We describe the symptoms, physical findings, diagnostic test results, and outcomes in a group of men poisoned with thallium and arsenic. Seven patients had evidence of elevated thallium levels, and 2 patients had elevated arsenic and thallium levels. The most commonly reported symptoms included myalgias, arthralgias, paresthesias, and dysesthesias. Five patients developed alopecia. All patients with symptoms and peripheral neuropathies had characteristic blackening of their hair roots. Initially treated with dimercaptosuccinic acid, patients were switched to multiple-dose activated charcoal after testing revealed thallium poisoning. By 6 months, all patients' symptoms and peripheral neuropathies improved, but 5 patients had ongoing psychiatric problems. Thallium remains a means of criminal poisoning and should be considered in any patient with a rapidly progressing peripheral neuropathy with or without alopecia.

  14. AKAP95 promotes cell cycle progression via interactions with cyclin E and low molecular weight cyclin E

    Science.gov (United States)

    Kong, Xiang-Yu; Zhang, Deng-Cheng; Zhuang, Wen-Xin; Hua, Su-Hang; Dai, Yue; Yuan, Yang-Yang; Feng, Li-Li; Huang, Qian; Teng, Bo-Gang; Yu, Xiu-Yi; Liu, Wen-Zhi; Zhang, Yong-Xing

    2016-01-01

    AKAP95 in lung cancer tissues showed higher expression than in paracancerous tissues. AKAP95 can bind with cyclin D and cyclin E during G1/S cell cycle transition, but its molecular mechanisms remain unclear. To identify the mechanism of AKAP95 in cell cycle progression, we performed AKAP95 transfection and silencing in A549 cells, examined AKAP95, cyclin E1 and cyclin E2 expression, and the interactions of AKAP95 with cyclins E1 and E2. Results showed that over-expression of AKAP95 promoted cell growth and AKAP95 bound cyclin E1 and E2, low molecular weight cyclin E1 (LWM-E1) and LWM-E2. Additionally AKAP95 bound cyclin E1 and LMW-E2 in the nucleus during G1/S transition, bound LMW-E1 during G1, S and G2/M, and bound cyclin E2 mainly on the nuclear membrane during interphase. Cyclin E2 and LMW-E2 were also detected. AKAP95 over-expression increased cyclin E1 and LMW-E2 expression but decreased cyclin E2 levels. Unlike cyclin E1 and LMW-E2 that were nuclear located during the G1, S and G1/S phases, cyclin E2 and LMW-E1 were expressed in all cell cycle phases, with cyclin E2 present in the cytoplasm and nuclear membrane, with traces in the nucleus. LMW-E1 was present in both the cytoplasm and nucleus. The 20 kDa form of LMW-E1 showed only cytoplasmic expression, while the 40 kDa form was nuclear expressed. The expression of AKAP95, cyclin E1, LMW-E1 and -E2, might be regulated by cAMP. We conclude that AKAP95 might promote cell cycle progression by interacting with cyclin E1 and LMW-E2. LMW-E2, but not cyclin E2, might be involved in G1/S transition. The binding of AKAP95 and LMW-E1 was found throughout cell cycle. PMID:27158371

  15. Synergistic effects of the combination of oxalate and ascorbate on arsenic extraction from contaminated soils.

    Science.gov (United States)

    Lee, Jae-Cheol; Kim, Eun Jung; Baek, Kitae

    2017-02-01

    Arsenic is often associated with iron oxides in soils due to its high affinity with iron oxides and the abundance of iron oxides in the environment. Dissolution of iron oxides can subsequently release arsenic associated with them into the environment, which results in the increase of arsenic mobility in the soil environment. In this study, arsenic extraction from soils via the dissolution of iron oxides was investigated using oxalate, ascorbate, and their combination in order to effectively remediate arsenic-contaminated soils. Oxalate mainly extracted iron from soils via a ligand-promoted reaction, while ascorbate extracted iron mainly via a reductive reaction. Arsenic extractions from soils by oxalate and ascorbate were shown to behave similarly to iron extractions, indicating the concurrent release of arsenic adsorbed on iron oxides upon the dissolution of iron oxides. The combination of oxalate and ascorbate greatly increased arsenic extraction, indicating the synergistic effects of the combination of oxalate and ascorbate on iron and arsenic extraction from soils. Oxalate and ascorbate are naturally-occurring organic reagents that have chelating and reducing capacity. Therefore, the use of oxalate and ascorbate is environmentally friendly and effective for the remediation of arsenic-contaminated soils.

  16. The role of arsenic compounds in oxidative stress and in the development of diabetes

    Directory of Open Access Journals (Sweden)

    Anna Bizoń

    2013-09-01

    Full Text Available For many years arsenic compounds were used in medicine, including treatment of skin diseases, malaria, diabetes, malaria, stomach ulcers, leukemia and in the eighteenth and the nineteenth century formed the basis of contemporary pharmacology. Due to its toxicity and carcinogenic activity, most of the compounds of this element were removed from use. The major cause of human arsenic toxicity is attributed to contamination of potable water from natural geological sources rather than from mining, smelting and agricultural sources (pesticides or fertilizers. Tobacco smoke also contains arsenic compounds. The characteristics of severe acute arsenic toxicity in humans include gastrointestinal discomfort, vomiting, diarrhea, skin lesions or even death. Chronic exposure frequently causes vascoocclusive disease (such as Blackfoot disease, and the development of lung, skin, liver, kidney and bladder cancers. Arsenic is a pro-inflammatory metal and appears to induce oxidative stress, apoptosis, affect cell proliferation and cell cycle progression. Generation of free radicals by arsenic is associated with its genotoxicity and contributes to the development of neoplastic lesions. Exposure to arsenic can also cause damage of the central nervous system, peripheral neuropathies, and behavioral changes. It was shown the association of exposure to arsenic and type 2 diabetes. Compounds with +3 oxidation state are more toxic and can induce tumor development. Arsenic interacts with other heavy metals, e.g. enhances the toxicity of cadmium nephropathy and acts antagonistically relative to selenium. Studies on the mechanism of interacting the toxicity of arsenic in the human body are crucial and point to lack of access to pure potable water in some regions of the world. People should be aware of the risks that are associated with exposure to arsenic because it is ubiquitous in the industry, as well as the environment. Arsenic is also involved in the spread of

  17. Gr-1+CD11b+ cells are responsible for tumor promoting effect of TGF-β in breast cancer progression.

    Science.gov (United States)

    Li, Zhaoyang; Pang, Yanli; Gara, Sudheer Kumar; Achyut, B R; Heger, Christopher; Goldsmith, Paul K; Lonning, Scott; Yang, Li

    2012-12-01

    One great challenge in our understanding of TGF-β cancer biology and the successful application of TGF-β-targeted therapy is that TGF-β works as both a tumor suppressor and a tumor promoter. The underlying mechanisms for its functional change remain to be elucidated. Using 4T1 mammary tumor model that shares many characteristics with human breast cancer, particularly its ability to spontaneously metastasize to the lungs, we demonstrate that Gr-1+CD11b+ cells or myeloid derived suppressor cells are important mediators in TGF-β regulation of mammary tumor progression. Depletion of Gr-1+CD11b+ cells diminished the antitumor effect of TGF-β neutralization. Two mechanisms were involved: first, treatment with TGF-β neutralization antibody (1D11) significantly decreased the number of Gr-1+CD11b+ cells in tumor tissues and premetastatic lung. This is mediated through increased Gr-1+CD11b+ cell apoptosis. In addition, 1D11 treatment significantly decreased the expression of Th2 cytokines and Arginase 1. Interestingly, the number and property of Gr-1+CD11b+ cells in peripheral blood/draining lymph nodes correlated with tumor size and metastases in response to 1D11 treatment. Our data suggest that the efficacy of TGF-β neutralization depends on the presence of Gr-1+CD11b+ cells, and these cells could be good biomarkers for TGF-β-targeted therapy.

  18. Highly expressed long non-coding RNA FOXD2-AS1 promotes non-small cell lung cancer progression via Wnt/β-catenin signaling.

    Science.gov (United States)

    Rong, Lin; Zhao, Ruixing; Lu, Jinxiu

    2017-03-11

    Non-small cell lung cancer (NSCLC) is one of the most common and aggressive tumors around the world. Long-noncoding RNAs (lncRNAs) have been recently shown to play important roles in regulating numerous biological processes including tumor progression. However, the role of lncRNA FOXD2-AS1 in NSCLC remains unclear. In this study, we found that lncRNA FOXD2-AS1 is significantly up-regulated in NSCLC tissues. Loss- and gain-function assays revealed that FOXD2-AS1 promotes NSCLC cell growth and NSCLC tumor progression. Furthermore, we also revealed that FOXD2-AS1 modulates Wnt/β-catenin signaling in NSCLC cells. Taken together, we conclude that lncRNA FOXD2-AS1 promotes NSCLC progression though Wnt/β-catenin signaling. These results suggest that lncRNA FOXD2-AS1 might act as a novel therapeutic target for NSCLC treatment.

  19. Arsenic, Anaerobes, and Astrobiology

    Science.gov (United States)

    Stolz, J. F.; Oremland, R. S.; Switzer Blum, J.; Hoeft, S. E.; Baesman, S. M.; Bennett, S.; Miller, L. G.; Kulp, T. R.; Saltikov, C.

    2013-12-01

    Arsenic is an element best known for its highly poisonous nature, so it is not something one would associate with being a well-spring for life. Yet discoveries made over the past two decades have delineated that not only are some microbes resistant to arsenic, but that this element's primary redox states can be exploited to conserve energy and support prokaryotic growth ('arsenotrophy') in the absence of oxygen. Hence, arsenite [As(III)] can serve as an electron donor for chemo- or photo-autotrophy while arsenate [As(V)] will serve as an electron acceptor for chemo-heterotrophs and chemo-autotrophs. The phylogenetic diversity of these microbes is broad, encompassing many individual species from diverse taxonomic groups in the Domain Bacteria, with fewer representatives in the Domain Archaea. Speculation with regard to the evolutionary origins of the key functional genes in anaerobic arsenic transformations (arrA and arxA) and aerobic oxidation (aioB) has led to a disputation as to which gene and function is the most ancient and whether arsenic metabolism extended back into the Archaean. Regardless of its origin, robust arsenic metabolism has been documented in extreme environments that are rich in their arsenic content, such as hot springs and especially hypersaline soda lakes associated with volcanic regions. Searles Lake, CA is an extreme, salt-saturated end member where vigorous arsenic metabolism occurs, but there is no detectable sulfate-reduction or methanogenesis. The latter processes are too weak bio-energetically to survive as compared with arsenotrophy, and are also highly sensitive to the abundance of borate ions present in these locales. These observations have implications with respect to the search for microbial life elsewhere in the Solar System where volcanic-like processes have been operative. Hence, because of the likelihood of encountering dense brines in the regolith of Mars (formed by evapo-concentration) or beneath the ice layers of Europa

  20. [Arsenic - Poison or medicine?].

    Science.gov (United States)

    Kulik-Kupka, Karolina; Koszowska, Aneta; Brończyk-Puzoń, Anna; Nowak, Justyna; Gwizdek, Katarzyna; Zubelewicz-Szkodzińska, Barbara

    2016-01-01

    Arsenic (As) is commonly known as a poison. Only a few people know that As has also been widely used in medicine. In the past years As and its compounds were used as a medicine for the treatment of such diseases as diabetes, psoriasis, syphilis, skin ulcers and joint diseases. Nowadays As is also used especially in the treatment of patients with acute promyelocytic leukemia. The International Agency for Research on Cancer (IARC) has recognized arsenic as an element with carcinogenic effect evidenced by epidemiological studies, but as previously mentioned it is also used in the treatment of neoplastic diseases. This underlines the specificity of the arsenic effects. Arsenic occurs widely in the natural environment, for example, it is present in soil and water, which contributes to its migration to food products. Long exposure to this element may lead to liver damages and also to changes in myocardium. Bearing in mind that such serious health problems can occur, monitoring of the As presence in the environmental media plays a very important role. In addition, the occupational risk of As exposure in the workplace should be identified and checked. Also the standards for As presence in food should be established. This paper presents a review of the 2015 publications based on the Medical database like PubMed and Polish Medical Bibliography. It includes the most important information about arsenic in both forms, poison and medicine.

  1. Chronic arsenic poisoning.

    Science.gov (United States)

    Hall, Alan H

    2002-03-10

    Symptomatic arsenic poisoning is not often seen in occupational exposure settings. Attempted homicide and deliberate long-term poisoning have resulted in chronic toxicity. Skin pigmentation changes, palmar and plantar hyperkeratoses, gastrointestinal symptoms, anemia, and liver disease are common. Noncirrhotic portal hypertension with bleeding esophageal varices, splenomegaly, and hypersplenism may occur. A metallic taste, gastrointestinal disturbances, and Mee's lines may be seen. Bone marrow depression is common. 'Blackfoot disease' has been associated with arsenic-contaminated drinking water in Taiwan; Raynaud's phenomenon and acrocyanosis also may occur. Large numbers of persons in areas of India, Pakistan, and several other countries have been chronically poisoned from naturally occurring arsenic in ground water. Toxic delirium and encephalopathy can be present. CCA-treated wood (chromated copper arsenate) is not a health risk unless burned in fireplaces or woodstoves. Peripheral neuropathy may also occur. Workplace exposure or chronic ingestion of arsenic-contaminated water or arsenical medications is associated with development of skin, lung, and other cancers. Treatment may incklude the use of chelating agents such as dimercaprol (BAL), dimercaptosuccinic acid (DMSA), and dimercaptopanesulfonic acid (DMPS).

  2. Arsenic hyperaccumulator Pteris Vittata L. and its arsenic accumulation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    An arsenic hyperaccumulator Pteris vittata L. (Chinese brake) was first discovered in China by means of field survey and greenhouse cultivation. Field survey showed that Chinese brake had large accumulating capacity to arsenic; the orders of arsenic content in different parts of the fern were as follows: leaves>leafstalks>roots, which is totally different from that of ordinary plants; bioaccumulation coefficients of the above ground parts of the fern decreased as a power function of soil arsenic contents. In the control of pot trials with normal unpolluted soil containing 9 mg/kg of arsenic, the bioaccumulation coefficients of the above ground parts and rhizoids of Chinese brake were as high as 71 and 80 respectively. Greenhouse cultivation in the contaminated soil from mining areas has shown that more than 1 times greater arsenic can be accumulated in the leaves of the fern than that of field samples with the largest content of 5070 mg/kg As on a dry matter basis. During greenhouse cultivation, arsenic content in the leaves of the fern increased linearly with time prolonging. Not only has Chinese brake extraordinary tolerance and accumulation to arsenic, but it grew rapidly with great biomass, wide distribution and easy adaptation to different environmental conditions as well. Therefore, it has great potential in future remediation of arsenic contamination. It also demonstrates important value for studies of arsenic physiology and biochemistry such as arsenic absorption, translocation and detoxification mechanisms in plants.

  3. Cardiac conduction block at multiple levels caused by arsenic trioxide therapy.

    Science.gov (United States)

    Kathirgamanathan, Kala; Angaran, Paul; Lazo-Langner, Alejandro; Gula, Lorne J

    2013-01-01

    We present a rare case of a woman aged 62 years with refractory acute promyelocytic leukemia treated with arsenic trioxide leading to progressive, multilevel cardiac conduction block. After chelation treatment with dimercaprol, there was normalization of conduction.

  4. Metabolism and toxicity of arsenicals in mammals.

    Science.gov (United States)

    Sattar, Adeel; Xie, Shuyu; Hafeez, Mian Abdul; Wang, Xu; Hussain, Hafiz Iftikhar; Iqbal, Zahid; Pan, Yuanhu; Iqbal, Mujahid; Shabbir, Muhammad Abubakr; Yuan, Zonghui

    2016-12-01

    Arsenic (As) is a metalloid usually found in organic and inorganic forms with different oxidation states, while inorganic form (arsenite As-III and arsenate As-v) is considered to be more hazardous as compared to organic form (methylarsonate and dimethylarsinate), with mild or no toxicity in mammals. Due to an increasing trend to using arsenicals as growth promoters or for treatment purposes, the understanding of metabolism and toxicity of As gets vital importance. Its toxicity is mainly depends on oxi-reduction states (As-III or As-v) and the level of methylation during the metabolism process. Currently, the exact metabolic pathways of As have yet to be confirmed in humans and food producing animals. Oxidative methylation and glutathione conjugation is believed to be major pathways of As metabolism. Oxidative methylation is based on conversion of Arsenite in to mono-methylarsonic acid and di-methylarsenic acid in mammals. It has been confirmed that As is only methylated in the presence of glutathione or thiol compounds, suggesting that As is being methylated in trivalent states. Subsequently, non-conjugated trivalent arsenicals are highly reactive with thiol which converts the trivalent arsenicals in to less toxic pentavalent forms. The glutathione conjugate stability of As is the most important factor for determining the toxicity. It can lead to DNA damage by alerting enzyme profile and production of reactive oxygen and nitrogen species which causes the oxidative stress. Moreover, As causes immune-dysfunction by hindering cellular and humeral immune response. The present review discussed different metabolic pathways and toxic outcomes of arsenicals in mammals which will be helpful in health risk assessment and its impact on biological world.

  5. Arsenic poisoning in cattle

    Energy Technology Data Exchange (ETDEWEB)

    McLennan, M.W.; Dodson, M.E.

    1972-06-01

    A case of acute arsenic poisoning in cattle was reported. The losses occurred on a property in the south east of South Australia. The weather had been hot for two or three days before the death occurred. The tank supplying the water trough had almost run dry. The cattle then attempted to meet their water requirements by drinking from the sheep dipping vat. A sample of rumen contents and a sample of water from the dipping vat were checked for arsenic. The rumen sample contained 45 ppM As/sub 2/O/sub 3/ and the sample of dipping fluid contained 200 ppM As. The lesions observed were similar to earlier reported arsenic poisoning. 5 references.

  6. Environmental source of arsenic exposure.

    Science.gov (United States)

    Chung, Jin-Yong; Yu, Seung-Do; Hong, Young-Seoub

    2014-09-01

    Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

  7. Promoting universal financial protection: evidence from seven low- and middle-income countries on factors facilitating or hindering progress.

    Science.gov (United States)

    McIntyre, Di; Ranson, Michael K; Aulakh, Bhupinder K; Honda, Ayako

    2013-09-24

    problem in LMICs. The case studies also highlighted the critical role of high-level political leadership in pursuing UHC policies and citizen support in sustaining these policies.This series demonstrates the value of promoting greater sharing of experiences on UHC reforms across LMICs. It also identifies key areas of future research on health care financing in LMICs that would support progress towards UHC.

  8. ARSENIC SPECIATION ANALYSIS IN HUMAN SALIVA

    Science.gov (United States)

    Background: Determination of arsenic species in human saliva is potentially useful for biomonitoring of human exposure to arsenic and for studying arsenic metabolism. However, there is no report on the speciation analysis of arsenic in saliva. Methods: Arsenic species in saliva ...

  9. 电化学增强催化的研究进展%RESEARCH PROGRESS OF ELECTROCHEMICAL PROMOTION OF CATALYSIS

    Institute of Scientific and Technical Information of China (English)

    陈海辉

    2014-01-01

    电化学增强催化(EPOC)通过电化学方式可在线控制化学反应进程,施加较小的电流或电势可以引起催化反应速率、产物产率或选择性有显著的变化,是近30年来电化学领域最令人激动的发现,对催化和电化学具有重大影响。本研究综述EPOC机理、研究应用进展,建议进一步研究EPOC的方向和技术路线。研究了EPOC型燃料电池堆反应器(MEPR),探索其传递特性、调控机制,有望获得基础性、前瞻性、战略性的科技成果。随着燃料电池的发展,催化膜成本将进一步降低,催化效率将显著提高,这种新型反应器最终将能满足工业规模化生产要求。%Electrochemical promotion of catalysis (EPOC) makes the chemical reaction process be online controlled, in which a smaller current or potential is applied to cause significant changes for catalytic reaction rate, product yield or selectivity of chemical reaction, so it is the most exciting discovery in the field of electrochemistry during the last 30 years, and has a significant impact on the catalytic and electrochemistry. The mechanisms and research progresses of EPOC are reviewed, the further direction and technology roadmap of EPOC study are indicated in this paper. The research of monolithic electrochemical promotion reactor (MEPR), to explore the transfer characteristics and the regulatory mechanism, would get some of fundamental, forward-looking and strategic technological achievements. But with the development of fuel cells, catalytic membrane costs will be further reduced, the catalytic efficiency will also be significantly improved, this new type of reactor will eventually be able to meet the requirements of industrial scale production.

  10. Down-regulation of neogenin accelerated glioma progression through promoter Methylation and its overexpression in SHG-44 Induced Apoptosis.

    Directory of Open Access Journals (Sweden)

    Xinmin Wu

    Full Text Available BACKGROUND: Dependence receptors have been proved to act as tumor suppressors in tumorigenesis. Neogenin, a DCC homologue, well known for its fundamental role in axon guidance and cellular differentiation, is also a dependence receptor functioning to control apoptosis. However, loss of neogenin has been reported in several kinds of cancers, but its role in glioma remains to be further investigated. METHODOLOGY/PRINCIPAL FINDINGS: Western blot analysis showed that neogenin level was lower in glioma tissues than in their matching surrounding non-neoplastic tissues (n = 13, p<0.01. By immunohistochemical analysis of 69 primary and 16 paired initial and recurrent glioma sections, we found that the loss of neogenin did not only correlate negatively with glioma malignancy (n = 69, p<0.01, but also glioma recurrence (n = 16, p<0.05. Kaplan-Meier plot and Cox proportional hazards modelling showed that over-expressive neogenin could prolong the tumor latency (n = 69, p<0.001, 1187.6 ± 162.6 days versus 687.4 ± 254.2 days and restrain high-grade glioma development (n = 69, p<0.01, HR: 0.264, 95% CI: 0.102 to 0.687. By Methylation specific polymerase chain reaction (MSP, we reported that neogenin promoter was methylated in 31.0% (9/29 gliomas, but absent in 3 kinds of glioma cell lines. Interestingly, the prevalence of methylation in high-grade gliomas was higher than low-grade gliomas and non-neoplastic brain tissues (n = 33, p<0.05 and overall methylation rate increased as glioma malignancy advanced. Furthermore, when cells were over-expressed by neogenin, the apoptotic rate in SHG-44 was increased to 39.7% compared with 8.1% in the blank control (p<0.01 and 9.3% in the negative control (p<0.01. CONCLUSIONS/SIGNIFICANCE: These observations recapitulated the proposed role of neogenin as a tumor suppressor in gliomas and we suggest its down-regulation owing to promoter methylation is a selective advantage for glioma genesis, progression and recurrence

  11. Specific disruption of Tsc1 in ovarian granulosa cells promotes ovulation and causes progressive accumulation of corpora lutea.

    Directory of Open Access Journals (Sweden)

    Lin Huang

    Full Text Available Tuberous sclerosis complex 1 (Tsc1 is a tumor suppressor negatively regulating mammalian target of rapamycin complex 1 (mTORC1. It is reported that mice lacking Tsc1 gene in oocytes show depletion of primordial follicles, resulting in premature ovarian failure and subsequent infertility. A recent study indicated that deletion of Tsc1 in somatic cells of the reproductive tract caused infertility of female mice. However, it is not known whether specific disruption of Tsc1 in granulosa cells influences the reproductive activity of female mice. To clarify this problem, we mated Tsc1(flox/flox mice with transgenic mice strain expressing cyp19-cre which exclusively expresses in granulosa cells of the ovary. Our results demonstrated that Tsc1(flox/flox; cyp19-cre mutant mice were fertile, ovulating more oocytes and giving birth to more pups than control Tsc1(flox/flox mice. Progressive accumulation of corpora lutea occurred in the Tsc1(flox/flox; cyp19-cre mutant mice with advanced age. These phenotypes could be explained by the elevated activity of mTORC1, as indicated by increased phosphorylation of rpS6, a substrate of S6 in the Tsc1(flox/flox; cyp19-cre mutant granulosa cells. In addition, rapamycin, a specific mTORC1 inhibitor, effectively rescued the phenotype caused by increased mTORC1 activity in the Tsc1(cko ovaries. Our data suggest that conditional knockout of Tsc1 in granulosa cells promotes reproductive activity in mice.

  12. ARSENIC REMOVAL TREATMENT OPTIONS FOR SINGLE FAMILY HOMES

    Science.gov (United States)

    The presentation provides information on POU and POE arsenic removal drinking water treatment systems. The presentation provides information on the arsenic rule, arsenic chemistry and arsenic treatment. The arsenic treatment options proposed for POU and POE treatment consist prim...

  13. Biosensor for organoarsenical herbicides and growth promoters.

    Science.gov (United States)

    Chen, Jian; Sun, Samio; Li, Chen-Zhong; Zhu, Yong-Guan; Rosen, Barry P

    2014-01-21

    The toxic metalloid arsenic is widely distributed in food, water, and soil. While inorganic arsenic enters the environment primarily from geochemical sources, methylarsenicals either result from microbial biotransformation of inorganic arsenic or are introduced anthropogenically. Methylarsenicals such as monosodium methylarsonic acid (MSMA) have been extensively utilized as herbicides, and aromatic arsenicals such as roxarsone (Rox) are used as growth promoters for poultry and swine. Organoarsenicals are degraded to inorganic arsenic. The toxicological effects of arsenicals depend on their oxidation state, chemical composition, and bioavailability. Here we report that the active forms are the trivalent arsenic-containing species. We constructed a whole-cell biosensor utilizing a modified ArsR repressor that is highly selective toward trivalent methyl and aromatic arsenicals, with essentially no response to inorganic arsenic. The biosensor was adapted for in vitro detection of organoarsenicals using fluorescence anisotropy of ArsR-DNA interactions. It detects bacterial biomethylation of inorganic arsenite both in vivo and in vitro with detection limits of 10(-7) M and linearity to 10(-6) M for phenylarsenite and 5 × 10(-6) M for methylarsenite. The biosensor detects reduced forms of MSMA and roxarsone and offers a practical, low cost method for detecting activate forms and breakdown products of organoarsenical herbicides and growth promoters.

  14. Arsenic release by indigenous bacteria Bacillus cereus from aquifer sediments at Datong Basin, northern China

    Science.gov (United States)

    Xie, Zuoming; Wang, Yanxin; Duan, Mengyu; Xie, Xianjun; Su, Chunli

    2011-03-01

    Endemic arsenic poisoning due to long-term drinking of high arsenic groundwater has been reported in Datong Basin, northern China. To investigate the effects of microbial activities on arsenic mobilization in contaminated aquifers, Bacillus cereus ( B. cereus) isolated from high arsenic aquifer sediments of the basin was used in our microcosm experiments. The arsenic concentration in the treatment with both bacteria and sodium citrate or glucose had a rapid increase in the first 18 d, and then, it declined. Supplemented with bacteria only, the concentration could increase on the second day. By contrast, the arsenic concentration in the treatment supplemented with sodium citrate or glucose was kept very low. These results indicate that bacterial activities promoted the release of arsenic in the sediments. Bacterial activities also influenced other geochemical parameters of the aqueous phase, such as pH, Eh, and the concentrations of dissolved Fe, Mn, and Al that are important controls on arsenic release. The removal of Fe, Mn, and Al from sediment samples was observed with the presence of B. cereus. The effects of microbial activities on Fe, Mn, and Al release were nearly the same as those on As mobilization. The pH values of the treatments inoculated with bacteria were lower than those without bacteria, still at alkaline levels. With the decrease of Eh values in treatments inoculated with bacteria, the microcosms became more reducing and are thus favorable for arsenic release.

  15. Arsenic release by indigenous bacteria Bacillus cereus from aquifer sediments at Datong Basin, northern China

    Institute of Scientific and Technical Information of China (English)

    Zuoming XIE; Yanxin WANG; Mengyu DUAN; Xianjun XIE; Chunli SU

    2011-01-01

    Endemic arsenic poisoning due to long-term drinking of high arsenic groundwater has been reported in Datong Basin, northern China. To investigate the effects of microbial activities on arsenic mobilization in contaminated aquifers, Bacillus cereus (B. cereus) isolated from high arsenic aquifer sediments of the basin was used in our microcosm experiments. The arsenic concentration in the treatment with both bacteria and sodium citrate or glucose had a rapid increase in the first 18 d, and then, it declined.Supplemented with bacteria only, the concentration could increase on the second day. By contrast, the arsenic concentration in the treatment supplemented with sodium citrate or glucose was kept very low. These results indicate that bacterial activities promoted the release of arsenic in the sediments. Bacterial activities also influenced other geochemical parameters of the aqueous phase, such as pH,Eh, and the concentrations of dissolved Fe, Mn, and Al that are important controls on arsenic release. The removal of Fe, Mn, and Al from sediment samples was observed with the presence of B. cereus. The effects of microbial activities on Fe, Mn, and Al release were nearly the same as those on As mobilization. The pH values of the treatments inoculated with bacteria were lower than those without bacteria, still at alkaline levels. With the decrease of Eh values in treatments inoculated with bacteria, the microcosms became more reducing and are thus favorable for arsenic release.

  16. Microbial Transformation of Arsenic

    Science.gov (United States)

    Stolz, J. F.

    2004-12-01

    Whether the source is natural or anthropogenic, it has become evident that arsenic is readily transformed by a great diversity of microbial species and has a robust biogeochemical cycle. Arsenic cycling primarily involves the oxidation of As(III) and the reduction of As(V). Over thirty arsenite oxidizing prokaryotes have been reported and include alpha, beta, and gamma Proteobacteria , Deinocci and Crenarchaeota. At least twenty species of arsenate-respiring prokaryotes are now known and include Crenarchaeota, thermophilic bacteria, low and high G+C gram positive bacteria, and gamma, delta, and epsilon Proteobacteria. These organisms are metabolically diverse, and depending on the species, capable of using other terminal electron acceptors (e.g., nitrate, selenate, fumarate, sulfate). In addition to inorganic forms (e.g., sodium arsenate) organoarsenicals can be utilized as a substrate. The feed additive roxarsone (3-nitro-4-hydroxyphenyl arsonic acid) has been shown to readily degrade leading to the release of inorganic arsenic (e.g., As(V)). Degradation proceeds via the cleavage of the arsenate functional group or the reduction of the nitro functional group and deamination. The rapid degradation (within 3 days) of roxarsone by Clostridium sp. strain OhILAs appears to follow the latter pathway and may involve Stickland reactions. The activities of these organisms affect the speciation and mobilization of arsenic, ultimately impacting water quality.

  17. Arsenic in shrimp from Kuwait

    Energy Technology Data Exchange (ETDEWEB)

    Bou-Olayan, A.H. [Kuwait Univ. (Kuwait); Al-Yakoob, S.; Al-Hossaini, M. [Kuwait Institute for Scientific Research (Kuwait)

    1995-04-01

    Arsenic is ubiquitous in the environment and can accumulate in food via contaminated soil, water or air. It enters the food chain through dry and wet atmospheric deposition. Combustion of oil and coal, use of arsenical fertilizers and pesticides and smelting of ores contributes significantly to the natural background of arsenic in soils and sediments. The metal can be transferred from soil to man through plants. In spite of variation in acute, subacute, and chronic toxic effects to plants and animals, evidence of nutritional essentiality of arsenic for rats, goats, and guinea pigs has been suggested, but has not been confirmed for humans. Adverse toxic effects of arsenic as well as its widespread distribution in the environment raises concern about levels of arsenic in man`s diet. Higher levels of arsenic in the diet can result in a higher accumulation rate. Arsenic levels in marine organisms are influenced by species differences, size of organism, and human activities. Bottom dwellers such as shrimp, crab, and lobster accumulate more arsenic than fish due to their frequent contact with bottom sediments. Shrimp constitute approximately 30% of mean total seafood consumption in Kuwait. This study was designed to determine the accumulation of arsenic in the commercially important jinga shrimp (Metapenaeus affinis) and grooved tiger prawn (Penaeus semisulcatus). 13 refs., 3 figs., 1 tab.

  18. Rural methods to mitigate arsenic contaminated water

    OpenAIRE

    Parajuli, Krishna

    2013-01-01

    Consumption of arsenic contaminated water is one of the burning issues in the rural world. Poor public awareness program about health effects of drinking arsenic contaminated water and the rural methods to mitigate this problem poses a great threat of arsenic poisoning many people of the rural world. In this thesis, arsenic removal efficiency and the working mechanism of four rural and economical arsenic mitigation technologies i.e. solar oxidation and reduction of arsenic (SORAS), Bucket tr...

  19. Arsenic-induced Aurora-A activation contributes to chromosome instability and tumorigenesis

    Science.gov (United States)

    Wu, Chin-Han; Tseng, Ya-Shih; Yang, Chao-Chun; Kao, Yu-Ting; Sheu, Hamm-Ming; Liu, Hsiao-Sheng

    2013-11-01

    Arsenic may cause serious environmental pollution and is a serious industrial problem. Depending on the dosage, arsenic may trigger the cells undergoing either proliferation or apoptosis-related cell death. Because of lack of the proper animal model to study arsenic induced tumorigenesis, the accurate risk level of arsenic exposure has not been determined. Arsenic shows genotoxic effect on human beings who uptake water contaminated by arsenic. Chromosome aberration is frequently detected in arsenic exposure-related diseases and is associated with increased oxidative stress and decreased DNA repairing activity, but the underlying mechanism remains elusive. Aurora-A is a mitotic kinase, over-expression of Aurora-A leads to centrosome amplification, chromosomal instability and cell transformation. We revealed that Aurora-A is over-expressed in the skin and bladder cancer patients from blackfoot-disease endemic areas. Our cell line studies reveal that arsenic exposure between 0.5 μM and 1 μM for 2-7 days are able to induce Aurora-A expression and activation based on promoter activity, RNA and protein analysis. Aurora-A overexpression further increases the frequency of unsymmetrical chromosome segregation through centrosome amplification followed by cell population accumulated at S phase in immortalized keratinocyte (HaCaT) and uroepithelial cells (E7). Furthermore, Aurora-A over-expression was sustained for 1-4 weeks by chronic treatment of immortalized bladder and skin cells with NaAsO2. Aurora-A promoter methylation and gene amplification was not detected in the long-term arsenic treated E7 cells. Furthermore, the expression level of E2F1 transcription factor (E2F1) is increased in the presence of arsenic, and arsenic-related Aurora-A over-expression is transcriptionally regulated by E2F1. We further demonstrated that overexpression of Aurora-A and mutant Ha-ras or Aurora-A and mutant p53 may act additively to trigger arsenic-related bladder and skin cancer

  20. Estrogen-induced SDF-1α production promotes the progression of ER-negative breast cancer via the accumulation of MDSCs in the tumor microenvironment

    Science.gov (United States)

    Ouyang, Liquan; Chang, Weilong; Fang, Bin; Qin, Jieting; Qu, Xincai; Cheng, Fanjun

    2016-01-01

    Estrogen plays a role in the processes of tumorigenesis, metastasis, and drug resistance in estrogen receptor (ER)-positive breast cancer (BC). Whether estrogen contributes to ER-negative BC is unclear. Here, we aimed to investigate whether estrogen could stimulate the secretion of stromal-derived factor-1 (SDF-1α) by cancer-associated fibroblasts (CAFs) to promote the progression of ER-negative BC. We transplanted ER-negative BC cells into ovariectomized mice, which was followed by continuous injection of estrogen, and found that estrogen promoted the tumorigenesis of BC. Furthermore, High levels of SDF-1α and tumor-infiltrating myeloid-derived suppressor cells (MDSCs) were detected in the estrogen treatment group. Estrogen stimulates secretion of SDF-1α by CAFs extracted from BC patients. Recombinant SDF-1α could recruit MDSCs isolated from bone marrow cells of mice. In addition, the co-culture of CAFs and MDSCs demonstrated that the recruitment of MDSCs was increased when CAFs were exposed to estrogen. Using AMD3100 to block the SDF-1α/CXCR4 axis or gemcitabine to delete MDSCs, we observed that both of these agents could neutralize the effect of estrogen on tumorigenesis. Together, these results suggest that estrogen may promote the progression of ER-negative BC by stimulating CAFs to secrete SDF-1α, which can recruit MDSCs to the tumor microenvironment to exert tumor-promoting effects. PMID:27996037

  1. Estrogen-induced SDF-1α production promotes the progression of ER-negative breast cancer via the accumulation of MDSCs in the tumor microenvironment.

    Science.gov (United States)

    Ouyang, Liquan; Chang, Weilong; Fang, Bin; Qin, Jieting; Qu, Xincai; Cheng, Fanjun

    2016-12-20

    Estrogen plays a role in the processes of tumorigenesis, metastasis, and drug resistance in estrogen receptor (ER)-positive breast cancer (BC). Whether estrogen contributes to ER-negative BC is unclear. Here, we aimed to investigate whether estrogen could stimulate the secretion of stromal-derived factor-1 (SDF-1α) by cancer-associated fibroblasts (CAFs) to promote the progression of ER-negative BC. We transplanted ER-negative BC cells into ovariectomized mice, which was followed by continuous injection of estrogen, and found that estrogen promoted the tumorigenesis of BC. Furthermore, High levels of SDF-1α and tumor-infiltrating myeloid-derived suppressor cells (MDSCs) were detected in the estrogen treatment group. Estrogen stimulates secretion of SDF-1α by CAFs extracted from BC patients. Recombinant SDF-1α could recruit MDSCs isolated from bone marrow cells of mice. In addition, the co-culture of CAFs and MDSCs demonstrated that the recruitment of MDSCs was increased when CAFs were exposed to estrogen. Using AMD3100 to block the SDF-1α/CXCR4 axis or gemcitabine to delete MDSCs, we observed that both of these agents could neutralize the effect of estrogen on tumorigenesis. Together, these results suggest that estrogen may promote the progression of ER-negative BC by stimulating CAFs to secrete SDF-1α, which can recruit MDSCs to the tumor microenvironment to exert tumor-promoting effects.

  2. Arsenic poisoning of Bangladesh groundwater

    Science.gov (United States)

    Nickson, Ross; McArthur, John; Burgess, William; Ahmed, Kazi Matin; Ravenscroft, Peter; Rahmanñ, Mizanur

    1998-09-01

    In Bangladesh and West Bengal, alluvial Ganges aquifers used for public water supply are polluted with naturally occurring arsenic, which adversely affects the health of millions of people. Here we show that the arsenic derives from the reductive dissolution of arsenic-rich iron oxyhydroxides, which in turn are derived from weathering of base-metal sulphides. This finding means it should now be possible, by sedimentological study of the Ganges alluvial sediments, to guide the placement of new water wells so they will be free of arsenic.

  3. Arsenic-induced plant growth of arsenic-hyperaccumulator Pteris vittata: Impact of arsenic and phosphate rock.

    Science.gov (United States)

    Han, Yong-He; Yang, Guang-Mei; Fu, Jing-Wei; Guan, Dong-Xing; Chen, Yanshan; Ma, Lena Q

    2016-04-01

    Phosphate rock (PR) has been shown to promote plant growth and arsenic (As) uptake by As-hyperaccumulator Pteris vittata (PV). However, little is known about its behaviors in agricultural soils. In this study, impact of 50 mg kg(-1) As and/or 1.5% PR amendment on plant As accumulation and growth was investigated by growing PV for 90 d in three agricultural soils. While As amendment significantly increased plant As uptake and substantially promoted PV growth, the opposite was observed with PR amendment. Arsenic amendment increased plant frond As from 16.9-265 to 961-6017 mg kg(-1),whereas PR amendment lowered frond As to 10.2-216 mg kg(-1). The As-induced plant growth stimulation was 69-71%. While PR amendment increased plant Ca and P uptake, As amendment showed opposite results. The PV biomass was highly correlated with plant As at r = 0.82, but with weak correlations with plant Ca or P at r < 0.30. This study confirmed that 1) As significantly promoted PV growth, probably independent of Ca or P uptake, 2) PR amendment didn't enhance plant growth or As uptake by PV in agricultural soils with adequate available P, and 3) PV effluxed arsenite (AsIII) growing in agricultural soils.

  4. Research progress on oxidative damage of liver and kidney exposed to arsenic%砷暴露对肝脏、肾脏氧化损害的研究进展

    Institute of Scientific and Technical Information of China (English)

    钟源霞; 孙文长

    2013-01-01

    砷污染广泛存在于水、土壤和空气中,全球70个国家230多个地区遭受砷污染.砷主要通过污染饮用水的方式进入人体,全球5 000多万人口的饮用水砷浓度超过50 μg/L,1亿4 000万人口饮用水的砷浓度超过10 μg/L.砷暴露诱导活性氧的产生增加,同时降低抗氧化酶、抗氧化物的水平,导致DNA突变、脂质过氧化和蛋白质羰基化增加.因此,砷的毒性机理目前认为是砷诱导机体产生氧化应激.砷暴露可以引起机体多脏器的损害,包括肝脏和肾脏,其机制与线粒体氧化损伤、细胞色素c的释放、诱导靶细胞凋亡有关.某些转录因子起保护作用,如Nrf2,其基因敲除小鼠在砷暴露后表现出明显的肝坏死及炎性细胞浸润.砷中毒的防治主要有螯合剂疗法和抗氧化剂疗法.%Arsenic contamination is widespread in water, soil and air, influences 70 countries over 230 regions and has resulted in the global human health hazards. More than 50 million people drink water with arsenic concentrations exceeding 50μg/L, and more than 140 million population exceeding 10 μg/L. Arsenic increases the production of reactive oxygen species, while reducing the levels of antioxidant enzymes and antioxidant, leading to DNA mutations, lipid peroxidation and protein carbonylation. Arsenic exposure can results in multi - organ damages, including liver and kidney. The mechanism is associated with mitochondrial oxidative damage, cytochrome c release and apoptosis. Some transcription factors, such as Nrf2, play a protective role, and the knockout mice of it showed significant liver necrosis and inflammatory cell infiltration. The major preventions and treatments of arsenic poisoning are chelating agents and antioxidants.

  5. Co-expression of Arabidopsis thaliana phytochelatin synthase and Treponema denticola cysteine desulfhydrase for enhanced arsenic accumulation.

    Science.gov (United States)

    Tsai, Shen-Long; Singh, Shailendra; Dasilva, Nancy A; Chen, Wilfred

    2012-02-01

    Arsenic is one of the most hazardous pollutants found in aqueous environments and has been shown to be a carcinogen. Phytochelatins (PCs), which are cysteine-rich and thio-reactive peptides, have high binding affinities for various metals including arsenic. Previously, we demonstrated that genetically engineered Saccharomyces cerevisiae strains expressing phytochelatin synthase (AtPCS) produced PCs and accumulated arsenic. In an effort to further improve the overall accumulation of arsenic, cysteine desulfhydrase, an aminotransferase that converts cysteine into hydrogen sulfide under aerobic condition, was co-expressed in order to promote the formation of larger AsS complexes. Yeast cells producing both AtPCS and cysteine desulfhydrase showed a higher level of arsenic accumulation than a simple cumulative effect of expressing both enzymes, confirming the coordinated action of hydrogen sulfide and PCs in the overall bioaccumulation of arsenic.

  6. Homicidal arsenic poisoning.

    Science.gov (United States)

    Duncan, Andrew; Taylor, Andrew; Leese, Elizabeth; Allen, Sam; Morton, Jackie; McAdam, Julie

    2015-07-01

    The case of a 50-year-old man who died mysteriously after being admitted to hospital is reported. He had raised the possibility of being poisoned prior to his death. A Coroner's post-mortem did not reveal the cause of death but this was subsequently established by post-mortem trace element analysis of liver, urine, blood and hair all of which revealed very high arsenic concentrations.

  7. Thiolated arsenicals in arsenic metabolism: Occurrence, formation, and biological implications.

    Science.gov (United States)

    Sun, Yuzhen; Liu, Guangliang; Cai, Yong

    2016-11-01

    Arsenic (As) is a notoriously toxic pollutant of health concern worldwide with potential risk of cancer induction, but meanwhile it is used as medicines for the treatment of different conditions including hematological cancers. Arsenic can undergo extensive metabolism in biological systems, and both toxicological and therapeutic effects of arsenic compounds are closely related to their metabolism. Recent studies have identified methylated thioarsenicals as a new class of arsenic metabolites in biological systems after exposure of inorganic and organic arsenicals, including arsenite, dimethylarsinic acid (DMA(V)), dimethylarsinous glutathione (DMA(III)GS), and arsenosugars. The increasing detection of thiolated arsenicals, including monomethylmonothioarsonic acid (MMMTA(V)), dimethylmonothioarsinic acid (DMMTA(V)) and its glutathione conjugate (DMMTA(V)GS), and dimethyldithioarsinic acid (DMDTA(V)) suggests that thioarsenicals may be important metabolites and play important roles in arsenic toxicity and therapeutic effects. Here we summarized the reported occurrence of thioarsenicals in biological systems, the possible formation pathways of thioarsenicals, and their toxicity, and discussed the biological implications of thioarsenicals on arsenic metabolism, toxicity, and therapeutic effects.

  8. Arsenic speciation in edible mushrooms.

    Science.gov (United States)

    Nearing, Michelle M; Koch, Iris; Reimer, Kenneth J

    2014-12-16

    The fruiting bodies, or mushrooms, of terrestrial fungi have been found to contain a high proportion of the nontoxic arsenic compound arsenobetaine (AB), but data gaps include a limited phylogenetic diversity of the fungi for which arsenic speciation is available, a focus on mushrooms with higher total arsenic concentrations, and the unknown formation and role of AB in mushrooms. To address these, the mushrooms of 46 different fungus species (73 samples) over a diverse range of phylogenetic groups were collected from Canadian grocery stores and background and arsenic-contaminated areas. Total arsenic was determined using ICP-MS, and arsenic speciation was determined using HPLC-ICP-MS and complementary X-ray absorption spectroscopy (XAS). The major arsenic compounds in mushrooms were found to be similar among phylogenetic groups, and AB was found to be the major compound in the Lycoperdaceae and Agaricaceae families but generally absent in log-growing mushrooms, suggesting the microbial community may influence arsenic speciation in mushrooms. The high proportion of AB in mushrooms with puffball or gilled morphologies may suggest that AB acts as an osmolyte in certain mushrooms to help maintain fruiting body structure. The presence of an As(III)-sulfur compound, for the first time in mushrooms, was identified in the XAS analysis. Except for Agaricus sp. (with predominantly AB), inorganic arsenic predominated in most of the store-bought mushrooms (albeit with low total arsenic concentrations). Should inorganic arsenic predominate in these mushrooms from contaminated areas, the risk to consumers under these circumstances should be considered.

  9. Early Involvement of Death-Associated Protein Kinase Promoter Hypermethylation in the Carcinogenesis of Barrett's Esophageal Adenocarcinoma and Its Association with Clinical Progression

    Directory of Open Access Journals (Sweden)

    Doerthe Kuester

    2007-03-01

    Full Text Available Esophageal Barrett's adenocarcinoma (BA develops through a multistage process, which is associated with the transcriptional silencing of tumor-suppressor genes by promoter CpG island hypermethylation. In this study, we explored the promoter hypermethylation and protein expression of proapoptotic deathassociated protein kinase (DAPK during the multistep Barrett's carcinogenesis cascade. Early BA and paired samples of premalignant lesions of 61 patients were analyzed by methylation-specific polymerase chain reaction and immunohistochemistry. For the association of clinicopathological markers and protein expression, an immunohistochemical tissue microarray analysis of 66 additional BAs of advanced tumor stages was performed. Hypermethylation of DAPK promoter was detected in 20% of normal mucosa, 50% of Barrett's metaplasia, 53% of dysplasia, and 60% of adenocarcinomas, and resulted in a marked decrease in DAPK protein expression (P < .01. The loss of DAPK protein was significantly associated with advanced depth of tumor invasion and advanced tumor stages (P < .001. Moreover, the severity of reflux esophagitis correlated significantly with the hypermethylation rate of the DAPK promoter (P < .003. Thus, we consider DAPK inactivation by promoter hypermethylation as an early event in Barrett's carcinogenesis and suggest that a decreased protein expression of DAPK likely plays a role in the development and progression of BA.

  10. Promoter hypermethylation of miR-34a contributes to the risk, progression, metastasis and poor survival of laryngeal squamous cell carcinoma.

    Science.gov (United States)

    Shen, Zhisen; Zhou, Chongchang; Li, Jinyun; Ye, Dong; Li, Qun; Wang, Jian; Cui, Xiang; Chen, Xiaoying; Bao, Tianlian; Duan, Shiwei

    2016-11-30

    MiR-34a is a direct transcriptional target of p53, which induces cell cycle arrest, senescence, and apoptosis. Recently, we and others identified abnormal expression of miR-34a in laryngeal squamous cell carcinoma (LSCC). The aim of our present study was to investigate the contribution of miR-34a promoter methylation to LSCC. Bisulfite pyrosequencing technology was applied to measure DNA methylation levels of six CpG sites in the miR-34a promoter from 104 LSCC tumor tissues and their corresponding adjacent tissues. Our results showed that the methylation levels of the miR-34a promoter were significantly higher in cancer tissues compared with the adjacent tissues (adjusted P=5.05E-10). A breakdown analysis for cigarette smoking behavior indicated a significantly elevated tendency of miR-34a methylation level in LSCC patients with smoking behavior but not in LSCC patients without smoking behavior (Smoking: Tumor vs Normal, adjusted P=3.12E-9; Non-smoking: Tumor vs Normal, adjusted P=0.073). In addition, miR-34a promoter methylation frequency remarkably increased in the advanced stage patients (adjusted P=0.003) and advanced T classified tumors (adjusted P=0.015). Moreover, significant association of miR-34a promoter hypermethylation with LSCC lymph metastasis was observed (adjusted P=0.002). Meanwhile, Kaplan-Meier survival curves results showed that high methylation of miR-34a promoter were associated with poor overall survival (log-rank test, P=0.023). Our study revealed that miR-34a promoter hypermethylation was a risk factor for LSCC, played a critical role in the disease progression and metastasis, and could serve as a poor prognostic factor for LSCC.

  11. CXCL17 expression by tumor cells recruits CD11b+Gr1 high F4/80- cells and promotes tumor progression.

    Directory of Open Access Journals (Sweden)

    Aya Matsui

    Full Text Available BACKGROUND: Chemokines are involved in multiple aspects of pathogenesis and cellular trafficking in tumorigenesis. In this study, we report that the latest member of the C-X-C-type chemokines, CXCL17 (DMC/VCC-1, recruits immature myeloid-derived cells and enhances early tumor progression. METHODOLOGY/PRINCIPAL FINDINGS: CXCL17 was preferentially expressed in some aggressive types of gastrointestinal, breast, and lung cancer cells. CXCL17 expression did not impart NIH3T3 cells with oncogenic potential in vitro, but CXCL17-expressing NIH3T3 cells could form vasculature-rich tumors in immunodeficient mice. Our data showed that CXCL17-expressing tumor cells increased immature CD11b(+Gr1(+ myeloid-derived cells at tumor sites in mice and promoted CD31(+ tumor angiogenesis. Extensive chemotactic assays proved that CXCL17-responding cells were CD11b(+Gr1(highF4/80(- cells (≈ 90% with a neutrophil-like morphology in vitro. Although CXCL17 expression could not increase the number of CD11b(+Gr1(+ cells in tumor-burdened SCID mice or promote metastases of low metastatic colon cancer cells, the existence of CXCL17-responding myeloid-derived cells caused a striking enhancement of xenograft tumor formation. CONCLUSIONS/SIGNIFICANCE: These results suggest that aberrant expression of CXCL17 in tumor cells recruits immature myeloid-derived cells and promotes tumor progression through angiogenesis.

  12. ARSENIC - SUSCEPTIBILITY & IN UTERO EFFECTS

    Science.gov (United States)

    Exposure to inorganic arsenic remains a serious public health problem at many locations worldwide. If has often been noted that prevalences of signs and symptoms of chronic arsenic poisoning differ among various populations. For example, skin lesions or peripheral vascular dis...

  13. Rhizosphere colonization and arsenic translocation in sunflower (Helianthus annuus L.) by arsenate reducing Alcaligenes sp. strain Dhal-L.

    Science.gov (United States)

    Cavalca, Lucia; Corsini, Anna; Bachate, Sachin Prabhakar; Andreoni, Vincenza

    2013-10-01

    In the present study, six arsenic-resistant strains previously isolated were tested for their plant growth promoting characteristics and heavy metal resistance, in order to choose one model strain as an inoculum for sunflower plants in pot experiments. The aim was to investigate the effect of arsenic-resistant strain on sunflower growth and on arsenic uptake from arsenic contaminated soil. Based on plant growth promoting characteristics and heavy metal resistance, Alcaligenes sp. strain Dhal-L was chosen as an inoculum. Beside the ability to reduce arsenate to arsenite via an Ars operon, the strain exhibited 1-amino-cyclopropane-1-carboxylic acid deaminase activity and it was also able to produce siderophore and indole acetic acid. Pot experiments were conducted with an agricultural soil contaminated with arsenic (214 mg kg⁻¹). A real time PCR method was set up based on the quantification of ACR3(2) type of arsenite efflux pump carried by Alcaligenes sp. strain Dhal-L, in order to monitor presence and colonisation of the strain in the bulk and rhizospheric soil. As a result of strain inoculation, arsenic uptake by plants was increased by 53 %, whereas ACR3(2) gene copy number in rhizospheric soil was 100 times higher in inoculated than in control pots, indicating the colonisation of strain. The results indicated that the presence of arsenate reducing strains in the rhizosphere of sunflower influences arsenic mobilization and promotes arsenic uptake by plant.

  14. Arsenic Mobility and Groundwater Extraction in Bangladesh

    Science.gov (United States)

    Harvey, Charles F.; Swartz, Christopher H.; Badruzzaman, A. B. M.; Keon-Blute, Nicole; Yu, Winston; Ali, M. Ashraf; Jay, Jenny; Beckie, Roger; Niedan, Volker; Brabander, Daniel; Oates, Peter M.; Ashfaque, Khandaker N.; Islam, Shafiqul; Hemond, Harold F.; Ahmed, M. Feroze

    2002-11-01

    High levels of arsenic in well water are causing widespread poisoning in Bangladesh. In a typical aquifer in southern Bangladesh, chemical data imply that arsenic mobilization is associated with recent inflow of carbon. High concentrations of radiocarbon-young methane indicate that young carbon has driven recent biogeochemical processes, and irrigation pumping is sufficient to have drawn water to the depth where dissolved arsenic is at a maximum. The results of field injection of molasses, nitrate, and low-arsenic water show that organic carbon or its degradation products may quickly mobilize arsenic, oxidants may lower arsenic concentrations, and sorption of arsenic is limited by saturation of aquifer materials.

  15. Technologies for Arsenic Removal from Water: Current Status and Future Perspectives

    Science.gov (United States)

    Nicomel, Nina Ricci; Leus, Karen; Folens, Karel; Van Der Voort, Pascal; Du Laing, Gijs

    2015-01-01

    This review paper presents an overview of the available technologies used nowadays for the removal of arsenic species from water. Conventionally applied techniques to remove arsenic species include oxidation, coagulation-flocculation, and membrane techniques. Besides, progress has recently been made on the utility of various nanoparticles for the remediation of contaminated water. A critical analysis of the most widely investigated nanoparticles is presented and promising future research on novel porous materials, such as metal organic frameworks, is suggested. PMID:26703687

  16. Technologies for Arsenic Removal from Water: Current Status and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Nina Ricci Nicomel

    2015-12-01

    Full Text Available This review paper presents an overview of the available technologies used nowadays for the removal of arsenic species from water. Conventionally applied techniques to remove arsenic species include oxidation, coagulation-flocculation, and membrane techniques. Besides, progress has recently been made on the utility of various nanoparticles for the remediation of contaminated water. A critical analysis of the most widely investigated nanoparticles is presented and promising future research on novel porous materials, such as metal organic frameworks, is suggested.

  17. A conserved cyclin-binding domain determines functional interplay between anaphase-promoting complex-Cdh1 and cyclin A-Cdk2 during cell cycle progression

    DEFF Research Database (Denmark)

    Lukas, C; Kramer, E R; Peters, J M;

    2001-01-01

    Periodic activity of the anaphase-promoting complex (APC) ubiquitin ligase determines progression through multiple cell cycle transitions by targeting cell cycle regulators for destruction. At the G(1)/S transition, phosphorylation-dependent dissociation of the Cdh1-activating subunit inhibits...... the APC, allowing stabilization of proteins required for subsequent cell cycle progression. Cyclin-dependent kinases (CDKs) that initiate and maintain Cdh1 phosphorylation have been identified. However, the issue of which cyclin-CDK complexes are involved has been a matter of debate, and the mechanism...... of how cyclin-CDKs interact with APC subunits remains unresolved. Here we substantiate the evidence that mammalian cyclin A-Cdk2 prevents unscheduled APC reactivation during S phase by demonstrating its periodic interaction with Cdh1 at the level of endogenous proteins. Moreover, we identified...

  18. Arsenic transport by zebrafish aquaglyceroporins

    Directory of Open Access Journals (Sweden)

    Landfear Scott M

    2009-11-01

    Full Text Available Abstract Background Arsenic is one of the most ubiquitous toxins and endangers the health of tens of millions of humans worldwide. It is a mainly a water-borne contaminant. Inorganic trivalent arsenic (AsIII is one of the major species that exists environmentally. The transport of AsIII has been studied in microbes, plants and mammals. Members of the aquaglyceroporin family have been shown to actively conduct AsIII and its organic metabolite, monomethylarsenite (MAsIII. However, the transport of AsIII and MAsIII in in any fish species has not been characterized. Results In this study, five members of the aquaglyceroporin family from zebrafish (Danio rerio were cloned, and their ability to transport water, glycerol, and trivalent arsenicals (AsIII and MAsIII and antimonite (SbIII was investigated. Genes for at least seven aquaglyceroporins have been annotated in the zebrafish genome project. Here, five genes which are close homologues to human AQP3, AQP9 and AQP10 were cloned from a zebrafish cDNA preparation. These genes were named aqp3, aqp3l, aqp9a, aqp9b and aqp10 according to their similarities to the corresponding human AQPs. Expression of aqp9a, aqp9b, aqp3, aqp3l and aqp10 in multiple zebrafish organs were examined by RT-PCR. Our results demonstrated that these aquaglyceroporins exhibited different tissue expression. They are all detected in more than one tissue. The ability of these five aquaglyceroporins to transport water, glycerol and the metalloids arsenic and antimony was examined following expression in oocytes from Xenopus leavis. Each of these channels showed substantial glycerol transport at equivalent rates. These aquaglyceroporins also facilitate uptake of inorganic AsIII, MAsIII and SbIII. Arsenic accumulation in fish larvae and in different tissues from adult zebrafish was studied following short-term arsenic exposure. The results showed that liver is the major organ of arsenic accumulation; other tissues such as gill, eye

  19. Chromatin inactivation precedes de novo dna methylation during the progressive epigenetic silencing of the rassf1a promoter

    Energy Technology Data Exchange (ETDEWEB)

    Strunnikova Maria; Schagdarsurengin, Undraga; Kehlen, Astrid; Garbe, James C.; Stampfer, Martha R.; Dammann, Reinhard

    2005-02-23

    Epigenetic inactivation of the RASSF1A tumor suppressor by CpG island methylation was frequently detected in cancer. However, the mechanisms of this aberrant DNA methylation are unknown. In the RASSF1A promoter, we characterized four Sp1 sites, which are frequently methylated in cancer. We examined the functional relationship between DNA methylation, histone modification, Sp1 binding, and RASSF1A expression in proliferating human mammary epithelial cells. With increasing passages, the transcription of RASSF1A was dramatically silenced. This inactivation was associated with deacetylation and lysine 9 trimethylation of histone H3 and an impaired binding of Sp1 at the RASSF1A promoter. In mammary epithelial cells that had overcome a stress-associated senescence barrier, a spreading of DNA methylation in the CpG island promoter was observed. When the RASSF1A-silenced cells were treated with inhibitors of DNA methyltransferase and histone deacetylase, binding of Sp1 and expression of RASSF1 A reoccurred. In summary, we observed that histone H3 deacetylation and H3 lysine 9 trimethylation occur in the same time window as gene inactivation and precede DNA methylation. Our data suggest that in epithelial cells, histone inactivation may trigger de novo DNA methylation of the RASSF1A promoter and this system may serve as a model for CpG island inactivation of tumor suppressor genes.

  20. Assessing tumor progression factors by somatic gene transfer into a mouse model: Bcl-xL promotes islet tumor cell invasion.

    Directory of Open Access Journals (Sweden)

    Yi-Chieh Nancy Du

    2007-10-01

    Full Text Available Tumors develop through multiple stages, implicating multiple effectors, but the tools to assess how candidate genes contribute to stepwise tumor progression have been limited. We have developed a novel system in which progression of phenotypes in a mouse model of pancreatic islet cell tumorigenesis can be used to measure the effects of genes introduced by cell-type-specific infection with retroviral vectors. In this system, bitransgenic mice, in which the rat insulin promoter (RIP drives expression of both the SV40 T antigen (RIP-Tag and the receptor for subgroup A avian leukosis virus (RIP-tva, are infected with avian viral vectors carrying cDNAs encoding candidate progression factors. Like RIP-Tag mice, RIP-Tag; RIP-tva bitransgenic mice develop isolated carcinomas by approximately 14 wk of age, after progression through well-defined stages that are similar to aspects of human tumor progression, including hyperplasia, angiogenesis, adenoma, and invasive carcinoma. When avian retroviral vectors carrying a green fluorescent protein marker were introduced into RIP-Tag; RIP-tva mice by intra-cardiac injection at the hyperplastic or early dysplastic stage of tumorigenesis, approximately 20% of the TVA-positive cells were infected and expressed green fluorescent proteins as measured by flow cytometry. Similar infection with vectors carrying cDNA encoding either of two progression factors, a dominant-negative version of cadherin 1 (dnE-cad or Bcl-xL, accelerated the formation of islet tumors with invasive properties and pancreatic lymph node metastasis. To begin studying the mechanism by which Bcl-xL, an anti-apoptotic protein, promotes invasion and metastasis, RIP-Tag; RIP-tva pancreatic islet tumor cells were infected in vitro with RCASBP-Bcl-xL. Although no changes were observed in rates of proliferation or apoptosis, Bcl-xL altered cell morphology, remodeled the actin cytoskeleton, and down-regulated cadherin 1; it also induced cell migration and

  1. Arsenic retention and transport behavior in the presence of typical anionic and nonionic surfactants.

    Science.gov (United States)

    Liang, Chuan; Wang, Xianliang; Peng, Xianjia

    2016-01-01

    The massive production and wide use of surfactants have resulted in a large amount of surfactant residuals being discharged into the environment, which could have an impact on arsenic behavior. In the present study, the influence of the anionic surfactant sodium dodecyl benzene sulfonate (SDBS) and nonionic surfactant polyethylene glycol octylphenyl ether (Triton X-100) on arsenic behavior was investigated in batch and column tests. The presence of SDBS and Triton X-100 reduced arsenic retention onto ferrihydrite (FH), enhanced arsenic transport through FH coated sand (FH-sand) columns and promoted arsenic release from the FH surface. With coexisting surfactants in solution, the equilibrium adsorbed amount of arsenic on FH decreased by up to 29.7% and the adsorption rate decreased by up to 52.3%. Pre-coating with surfactants caused a decrease in the adsorbed amount and adsorption rate of arsenic by up to 15.1% and 58.3%, respectively. Because of the adsorption attenuation caused by surfactants, breakthrough of As(V) and As(III) with SDBS in columns packed with FH-sand was 23.8% and 14.3% faster than that in those without SDBS, respectively. In columns packed with SDBS-coated FH-sand, transport of arsenic was enhanced to a greater extent. Breakthrough of As(V) and As(III) was 52.4% and 43.8% faster and the cumulative retention amount was 44.5% and 57.3% less than that in pure FH-sand column systems, respectively. Mobilization of arsenic by surfactants increased with the increase of the initial adsorbed amount of arsenic. The cumulative release amount of As(V) and As(III) from the packed column reached 10.8% and 36.0%, respectively.

  2. Microbial responses to environmental arsenic.

    Science.gov (United States)

    Páez-Espino, David; Tamames, Javier; de Lorenzo, Víctor; Cánovas, David

    2009-02-01

    Microorganisms have evolved dynamic mechanisms for facing the toxicity of arsenic in the environment. In this sense, arsenic speciation and mobility is also affected by the microbial metabolism that participates in the biogeochemical cycle of the element. The ars operon constitutes the most ubiquitous and important scheme of arsenic tolerance in bacteria. This system mediates the extrusion of arsenite out of the cells. There are also other microbial activities that alter the chemical characteristics of arsenic: some strains are able to oxidize arsenite or reduce arsenate as part of their respiratory processes. These type of microorganisms require membrane associated proteins that transfer electrons from or to arsenic (AoxAB and ArrAB, respectively). Other enzymatic transformations, such as methylation-demethylation reactions, exchange inorganic arsenic into organic forms contributing to its complex environmental turnover. This short review highlights recent studies in ecology, biochemistry and molecular biology of these processes in bacteria, and also provides some examples of genetic engineering for enhanced arsenic accumulation based on phytochelatins or metallothionein-like proteins.

  3. ChIP-seq in studying epigenetic mechanisms of disease and promoting precision medicine: progresses and future directions.

    Science.gov (United States)

    Yan, Huihuang; Tian, Shulan; Slager, Susan L; Sun, Zhifu

    2016-09-01

    Chromatin immunoprecipitation followed by sequencing (ChIP-seq) is widely used for mapping histone modifications, histone proteins, chromatin regulators, transcription factors and other DNA-binding proteins. It has played a significant role in our understanding of disease mechanisms and in exploring epigenetic changes for potential clinical applications. However, the conventional protocol requires large amounts of starting material and does not quantify the actual occupancy, limiting its applications in clinical settings. Herein we summarize the latest progresses in utilizing ChIP-seq to link epigenetic alterations to disease initiation and progression, and the implications in precision medicine. We provide an update on the newly developed ChIP-seq protocols, especially those suitable for scare clinical samples. Technical and analytical challenges are outlined together with recommendations for improvement. Finally, future directions in expediting ChIP-seq use in clinic are discussed.

  4. Human Cdc14B promotes progression through mitosis by dephosphorylating Cdc25 and regulating Cdk1/cyclin B activity.

    Directory of Open Access Journals (Sweden)

    Indra Tumurbaatar

    Full Text Available Entry into and progression through mitosis depends on phosphorylation and dephosphorylation of key substrates. In yeast, the nucleolar phosphatase Cdc14 is pivotal for exit from mitosis counteracting Cdk1-dependent phosphorylations. Whether hCdc14B, the human homolog of yeast Cdc14, plays a similar function in mitosis is not yet known. Here we show that hCdc14B serves a critical role in regulating progression through mitosis, which is distinct from hCdc14A. Unscheduled overexpression of hCdc14B delays activation of two master regulators of mitosis, Cdc25 and Cdk1, and slows down entry into mitosis. Depletion of hCdc14B by RNAi prevents timely inactivation of Cdk1/cyclin B and dephosphorylation of Cdc25, leading to severe mitotic defects, such as delay of metaphase/anaphase transition, lagging chromosomes, multipolar spindles and binucleation. The results demonstrate that hCdc14B-dependent modulation of Cdc25 phosphatase and Cdk1/cyclin B activity is tightly linked to correct chromosome segregation and bipolar spindle formation, processes that are required for proper progression through mitosis and maintenance of genomic stability.

  5. Factors Affecting Arsenic Methylation in Arsenic-Exposed Humans: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Shen, Hui; Niu, Qiang; Xu, Mengchuan; Rui, Dongsheng; Xu, Shangzhi; Feng, Gangling; Ding, Yusong; Li, Shugang; Jing, Mingxia

    2016-02-06

    Chronic arsenic exposure is a critical public health issue in many countries. The metabolism of arsenic in vivo is complicated because it can be influenced by many factors. In the present meta-analysis, two researchers independently searched electronic databases, including the Cochrane Library, PubMed, Springer, Embase, and China National Knowledge Infrastructure, to analyze factors influencing arsenic methylation. The concentrations of the following arsenic metabolites increase (parsenic exposure: inorganic arsenic (iAs), monomethyl arsenic (MMA), dimethyl arsenic (DMA), and total arsenic. Additionally, the percentages of iAs (standard mean difference (SMD): 1.00; 95% confidence interval (CI): 0.60-1.40; parsenic methylation, and arsenic methylation is more efficient in women than in men. The results of this analysis may provide information regarding the role of arsenic oxidative methylation in the arsenic poisoning process.

  6. Structure and regulation of an archaebacterial promoter: An in vivo study. Progress report, August 1, 1991--March 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, C.J.

    1993-06-01

    We have established that a 100 bp DNA fragment from the Haloferax volcanii tRNALys gene directs transcription in vivo. This element served as the starting point for a detailed analysis of the requirements for in vivo transcription. Among several gene tentatively identified as reporter elements, we selected a eukaryotic intron-containing tRNAPro gene for when it is driven by the H. volcanii tRNALys promoter fragment, produces a single small transcript. Transcript analysis, by Sl mapping and primer extension, showed that this RNA initiated at the expected tRNALys BoxB sequence and terminated in the tRNAPro RNA Pol III termination element present on the DNA fragment. In initial studies we determined that the 3 inches proximal region of this tRNALys promoter element was sufficient for transcription initiation in vivo. This 40 bp region contains only the BoxA and BoxB regions and short purine rich regions 5 inches to the BoxA and BoxB sequence. Using the tRNAPro gene as the reporter and this minimal promoter, we performed a comprehensive analysis of the BoxA region. Each position of the BoxA region was converted to an four possible nucleotides and the transcription of 36 mutants was quantitated. Among the sites analyzed, only five of the positions showed high levels of discrimination; the preferred BoxA element was 5 inches-TT({sub T}/A)({sup A}/T) ANNNN-3 inches. Mutational analysis demonstrated that a transition from T-rich to A-rich sequences in the BoxA element is essential and that there is some flexibility in the location of the ``TA`` sequence. Additionally the TA sequence appears to determine the location of the transcription start site. The BoxA element defined in this study is similar to those observed for Sulfolobus and the methanogen promoters, and supports the hypothesis that a similar core promoter element is used by all archaeal RNA polymerases.

  7. RABL6A promotes G1-S phase progression and pancreatic neuroendocrine tumor cell proliferation in an Rb1-dependent manner.

    Science.gov (United States)

    Hagen, Jussara; Muniz, Viviane P; Falls, Kelly C; Reed, Sara M; Taghiyev, Agshin F; Quelle, Frederick W; Gourronc, Francoise A; Klingelhutz, Aloysius J; Major, Heather J; Askeland, Ryan W; Sherman, Scott K; O'Dorisio, Thomas M; Bellizzi, Andrew M; Howe, James R; Darbro, Benjamin W; Quelle, Dawn E

    2014-11-15

    Mechanisms of neuroendocrine tumor (NET) proliferation are poorly understood, and therapies that effectively control NET progression and metastatic disease are limited. We found amplification of a putative oncogene, RABL6A, in primary human pancreatic NETs (PNET) that correlated with high-level RABL6A protein expression. Consistent with those results, stable silencing of RABL6A in cultured BON-1 PNET cells revealed that it is essential for their proliferation and survival. Cells lacking RABL6A predominantly arrested in G1 phase with a moderate mitotic block. Pathway analysis of microarray data suggested activation of the p53 and retinoblastoma (Rb1) tumor-suppressor pathways in the arrested cells. Loss of p53 had no effect on the RABL6A knockdown phenotype, indicating that RABL6A functions independent of p53 in this setting. By comparison, Rb1 inactivation partially restored G1 to S phase progression in RABL6A-knockdown cells, although it was insufficient to override the mitotic arrest and cell death caused by RABL6A loss. Thus, RABL6A promotes G1 progression in PNET cells by inactivating Rb1, an established suppressor of PNET proliferation and development. This work identifies RABL6A as a novel negative regulator of Rb1 that is essential for PNET proliferation and survival. We suggest RABL6A is a new potential biomarker and target for anticancer therapy in PNET patients.

  8. Ubiquitin ligase UBE3C promotes melanoma progression by increasing epithelial-mesenchymal transition in melanoma cells

    OpenAIRE

    TANG, Li; Yi, Xue-Mei; Chen, Jia; Chen, Fu-Juan; Lou, Wei; Gao, Yun-Lu; Zhou, Jing; Su, Li-Na; Xu, Xin; Lu, Jia-Qing; Ma, Jun; Yu, Ning; Ding, Yang-Feng

    2016-01-01

    Melanoma is the most aggressive type of skin cancer, exhibiting extensive local invasion and early distant metastasis. Aberrant expression of ubiquitin-protein ligase E3C (UBE3C) plays a key role in tumor development and progression. In the present study, we analyzed UBE3C expression in samples of cancerous and normal skin tissue. Levels of UBE3C expression were much higher in primary and metastatic melanoma tissues than in normal skin, cutaneous squamous cell carcinoma or basal cell carcinom...

  9. MicroRNA-124 slows down the progression of Huntington′s disease by promoting neurogenesis in the striatum

    Directory of Open Access Journals (Sweden)

    Tian Liu

    2015-01-01

    Full Text Available MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington′s disease mouse models and patients is decreased. However, the effects of microRNA-124 on the progression of Huntington′s disease have not been reported. Results from this study showed that microRNA-124 increased the latency to fall for each R6/2 Huntington′s disease transgenic mouse in the rotarod test. 5-Bromo-2′-deoxyuridine (BrdU staining of the striatum shows an increase in neurogenesis. In addition, brain-derived neurotrophic factor and peroxisome proliferator-activated receptor gamma coactivator 1-alpha protein levels in the striatum were increased and SRY-related HMG box transcription factor 9 protein level was decreased. These findings suggest that microRNA-124 slows down the progression of Huntington′s disease possibly through its important role in neuronal differentiation and survival.

  10. Pro-inflammatory-Related Loss of CXCL12 Niche Promotes Acute Lymphoblastic Leukemic Progression at the Expense of Normal Lymphopoiesis

    Science.gov (United States)

    Balandrán, Juan Carlos; Purizaca, Jessica; Enciso, Jennifer; Dozal, David; Sandoval, Antonio; Jiménez-Hernández, Elva; Alemán-Lazarini, Leticia; Perez-Koldenkova, Vadim; Quintela-Núñez del Prado, Henry; Rios de los Ríos, Jussara; Mayani, Héctor; Ortiz-Navarrete, Vianney; Guzman, Monica L.; Pelayo, Rosana

    2017-01-01

    Pediatric oncology, notably childhood acute lymphoblastic leukemia (ALL), is currently one of the health-leading concerns worldwide and a biomedical priority. Decreasing overall leukemia mortality in children requires a comprehensive understanding of its pathobiology. It is becoming clear that malignant cell-to-niche intercommunication and microenvironmental signals that control early cell fate decisions are critical for tumor progression. We show here that the mesenchymal stromal cell component of ALL bone marrow (BM) differ from its normal counterpart in a number of functional properties and may have a key role during leukemic development. A decreased proliferation potential, contrasting with the strong ability of producing pro-inflammatory cytokines and an aberrantly loss of CXCL12 and SCF, suggest that leukemic lymphoid niches in ALL BM are unique and may exclude normal hematopoiesis. Cell competence ex vivo assays within tridimensional coculture structures indicated a growth advantage of leukemic precursor cells and their niche remodeling ability by CXCL12 reduction, resulting in leukemic cell progression at the expense of normal niche-associated lymphopoiesis. PMID:28111575

  11. n-Butyl benzyl phthalate promotes breast cancer progression by inducing expression of lymphoid enhancer factor 1.

    Directory of Open Access Journals (Sweden)

    Tsung-Hua Hsieh

    Full Text Available Environmental hormones play important roles in regulating the expression of genes involved in cell proliferation, drug resistance, and breast cancer risk; however, their precise role in human breast cancer cells during cancer progression remains unclear. To elucidate the effect of the most widely used industrial phthalate, n-butyl benzyl phthalate (BBP, on cancer progression, we evaluated the results of BBP treatment using a whole human genome cDNA microarray and MetaCore software and selected candidate genes whose expression was changed by more than ten-fold by BBP compared with controls to analyze the signaling pathways in human breast cancer initiating cells (R2d. A total of 473 genes were upregulated, and 468 were downregulated. Most of these genes are involved in proliferation, epithelial-mesenchymal transition, and angiogenesis signaling. BBP induced the viability, invasion and migration, and tube formation in vitro, and Matrigel plug angiogenesis in vivo of R2d and MCF-7. Furthermore, the viability and invasion and migration of these cell lines following BBP treatment was reduced by transfection with a small interfering RNA targeting the mRNA for lymphoid enhancer-binding factor 1; notably, the altered expression of this gene consistently differentiated tumors expressing genes involved in proliferation, epithelial-mesenchymal transition, and angiogenesis. These findings contribute to our understanding of the molecular impact of the environmental hormone BBP and suggest possible strategies for preventing and treating human breast cancer.

  12. MicroRNA-124 slows down the progression of Huntington’s disease by promoting neurogenesis in the striatum

    Institute of Scientific and Technical Information of China (English)

    Tian Liu; Wooseok Im; Inhee Mook-Jung; Manho Kim

    2015-01-01

    MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington’s disease mouse models and patients is decreased. However, the effects of microRNA-124 on the progression of Huntington’s disease have not been reported. Results from this study showed that microRNA-124 increased the latency to fall for each R6/2 Hunting-ton’s disease transgenic mouse in the rotarod test. 5-Bromo-2’-deoxyuridine (BrdU) staining of the striatum shows an increase in neurogenesis. In addition, brain-derived neurotrophic factor and peroxisome proliferator-activated receptor gamma coactivator 1-alpha protein levels in the striatum were increased and SRY-related HMG box transcription factor 9 protein level was de-creased. These ifndings suggest that microRNA-124 slows down the progression of Huntington’s disease possibly through its important role in neuronal differentiation and survival.

  13. PUF-8 Functions Redundantly with GLD-1 to Promote the Meiotic Progression of Spermatocytes in Caenorhabditis elegans.

    Science.gov (United States)

    Priti, Agarwal; Subramaniam, Kuppuswamy

    2015-06-10

    Successful meiotic progression of germ cells is crucial for gametogenesis. Defects in this process affect proper genetic transmission and sometimes lead to tumor formation in the germline. In Caenorhabditis elegans, the RNA-binding protein GLD-1 is essential for the meiotic development of oocytes. However, its role during spermatogenesis has not been understood. Here, we show that GLD-1 functions redundantly with the PUF family protein PUF-8 to ensure proper meiotic development of spermatocytes. When grown at 20°-the standard laboratory temperature for C. elegans growth-primary spermatocytes in both gld-1 and puf-8 single-mutant males and hermaphrodites complete the meiotic divisions normally. By contrast, some of the gld-1; puf-8 double-mutant spermatocytes exit meiosis and form germ cell tumors in both sexes. During larval development, gld-1; puf-8 double-mutant germ cells begin to express the meiotic marker HIM-3, lose P granules, and form the sperm-specific membranous organelle, which are characteristics of developing spermatocytes. However, some of these cells quickly lose HIM-3 and form germ cell tumors that lack membranous organelle but contain P granules. Mutations that block meiotic progression at late pachytene or diakinetic stage fail to arrest the tumorigenesis, suggesting that the gld-1; puf-8 double-mutant spermatocytes exit meiosis prior to the completion of pachytene. Together, results presented here uncover a novel function for gld-1 in the meiotic development of spermatocytes in both hermaphrodites and males.

  14. Discovery of the Arsenic Isotopes

    CERN Document Server

    Shore, A; Heim, M; Schuh, A; Thoennessen, M

    2009-01-01

    Twenty-nine arsenic isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  15. New Arsenic Cross Section Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Toshihiko [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-04

    This report presents calculations for the new arsenic cross section. Cross sections for 73,74,75 As above the resonance range were calculated with a newly developed Hauser-Feshbach code, CoH3.

  16. Melanocytes and keratinocytes have distinct and shared responses to ultraviolet radiation and arsenic.

    Science.gov (United States)

    Cooper, K L; Yager, J W; Hudson, L G

    2014-01-30

    The rise of melanoma incidence in the United States is a growing public health concern. A limited number of epidemiology studies suggest an association between arsenic levels and melanoma risk. Arsenic acts as a co-carcinogen with ultraviolet radiation (UVR) for the development of squamous cell carcinoma and proposed mechanisms include generation of oxidative stress by arsenic and UVR and inhibition of UVR-induced DNA repair by arsenic. In this study, we investigate similarities and differences in response to arsenic and UVR in keratinocytes and melanocytes. Normal melanocytes are markedly more resistant to UVR-induced cytotoxicity than normal keratinocytes, but both cell types are equally sensitive to arsenite. Melanocytes were more resistant to arsenite and UVR stimulation of superoxide production than keratinocytes, but the concentration of arsenite necessary to inhibit the activity of the DNA repair protein poly(ADP-ribose)polymerase and enhance retention of UVR-induced DNA damage was essentially equivalent in both cell types. These findings suggest that although melanocytes are less sensitive than keratinocytes to initial UVR-mediated DNA damage, both of these important target cells in the skin share a mechanism related to arsenic inhibition of DNA repair. These findings suggest that concurrent chronic arsenic exposure could promote retention of unrepaired DNA damage in melanocytes and act as a co-carcinogen in melanoma.

  17. A biosensor for organoarsenical herbicides and growth promoters

    Science.gov (United States)

    Chen, Jian; Sun, Samio; Li, Chen-Zhong; Zhu, Yong-Guan; Rosen, Barry P.

    2014-01-01

    The toxic metalloid arsenic is widely distributed in food, water, and soil. While inorganic arsenic enters the environment primarily from geochemical sources, methylarsenicals either result from microbial biotransformation of inorganic arsenic or are introduced anthropogenically. Methylarsenicals such as monosodium methylarsonic acid (MSMA) have been extensively utilized as herbicides, and aromatic arsenicals such as roxarsone (Rox) are used as growth promoters for poultry and swine. Organoarsenicals are degraded to inorganic arsenic. The toxicological effects of arsenicals depend on their oxidation state, chemical composition, and bioavailability. Here we report that the active forms are the trivalent arsenic-containing species. We constructed a whole-cell biosensor utilizing a modified ArsR repressor that is highly selective toward trivalent methyl and aromatic arsenicals, with essentially no response to inorganic arsenic. The biosensor was adapted for in vitro detection of organoarsenicals using fluorescence anisotropy of ArsR-DNA interactions. It detects bacterial biomethylation of inorganic arsenite both in vivo and in vitro with detection limits of 10−7 M and linearity to 10−6 M for phenylarsenite and 5×10−6 M for methylarsenite. The biosensor detects reduced forms of MSMA and roxarsone and offers a practical, low cost method for detecting activate forms and breakdown products of organoarsenical herbicides and growth promoters. PMID:24359149

  18. Overexpressed KDM5B is associated with the progression of glioma and promotes glioma cell growth via downregulating p21

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Bin [Department of Neurosurgery, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038 (China); Hu, Zhiqiang, E-mail: zhiqhutg@126.com [Department of Neurosurgery, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038 (China); Huang, Hui; Zhu, Guangtong; Xiao, Zhiyong [Department of Neurosurgery, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038 (China); Wan, Weiqing; Zhang, Peng; Jia, Wang; Zhang, Liwei [Department of Neurosurgery, Beijing Tian Tan Hospital, Capital Medical University, Beijing 100050 (China)

    2014-11-07

    Highlights: • KDM5B is overexpressed in glioma samples. • KDM5B stimulated proliferation of glioma cells. • Inhibition of p21contributes to KDM5B-induced proliferation. - Abstract: Epigenetic alterations such as aberrant expression of histone-modifying enzymes have been implicated in tumorigenesis. Upregulation of lysine (K)-specific demethylase 5B (KDM5B) has been reported in a variety of malignant tumors. However, the impact of KDM5B in glioma remains unclear. The objective of this study was to investigate the expression and prognostic value of KDM5B in glioma. In clinical glioma samples, we found that KDM5B expression was significantly upregulated in cancer lesions compared with normal brain tissues. Kaplan–Meier analysis showed that patients with glioma and higher KDM5B expression tend to have shorter overall survival time. By silencing or overexpressing KDM5B in glioma cells, we found that KDM5B could promote cell growth both in vitro and in vivo. Moreover, we demonstrated that KDM5B promoted glioma proliferation partly via regulation of the expression of p21. Our study provided evidence that KDM5B functions as a novel tumor oncogene in glioma and may be a potential therapeutic target for glioma management.

  19. Nutrient-induced FNIP degradation by SCFβ-TRCP regulates FLCN complex localization and promotes renal cancer progression.

    Science.gov (United States)

    Nagashima, Katsuyuki; Fukushima, Hidefumi; Shimizu, Kouhei; Yamada, Aya; Hidaka, Masumi; Hasumi, Hisashi; Ikebe, Tetsuro; Fukumoto, Satoshi; Okabe, Koji; Inuzuka, Hiroyuki

    2017-02-07

    Folliculin-interacting protein 1 and 2 (FNIP1 and FNIP2) play critical roles in preventing renal malignancy through their association with the tumor suppressor FLCN. Mutations in FLCN are associated with Birt-Hogg-Dubé (BHD) syndrome, a rare disorder with increased risk of renal cancer. Recent studies indicated that FNIP1/FNIP2 double knockout mice display enlarged polycystic kidneys and renal carcinoma, which phenocopies FLCN knockout mice, suggesting that these two proteins function together to suppress renal cancer. However, the molecular mechanism functionally linking FNIP1/FNIP2 and FLCN remains largely elusive. Here, we demonstrated that FNIP2 protein is unstable and subjected to proteasome-dependent degradation via β-TRCP and Casein Kinase 1 (CK1)-directed ubiquitination in a nutrition-dependent manner. Degradation of FNIP2 leads to lysosomal dissociation of FLCN and subsequent lysosomal association of mTOR, which in turn promotes the proliferation of renal cancer cells. These results indicate that SCFβ-TRCP negatively regulates the FLCN complex by promoting FNIP degradation and provide molecular insight into the pathogenesis of BHD-associated renal cancer.

  20. New Mechanisms of Tumor-Associated Macrophages on Promoting Tumor Progression: Recent Research Advances and Potential Targets for Tumor Immunotherapy

    Directory of Open Access Journals (Sweden)

    Qiujun Guo

    2016-01-01

    Full Text Available The majority of basic and clinical studies have shown a protumor function of tumor-associated macrophages (TAMs, which represent a large proportion of matrix cells. TAMs promote tumorigenesis, and their number is related to the malignancy degree and poor prognosis of many kinds of tumors. Macrophage plasticity makes it possible to change the tumor microenvironment and remodel antitumor immunity during cancer immunotherapy. Increasing numbers of studies have revealed the effects of TAMs on the tumor microenvironment, for example, via promotion of tumor growth and tumorigenesis and through an increase in the number of cancer stem cells or via facilitation of angiogenesis, lymphangiogenesis, and metastasis. Investigators also proposed tumor-immunological treatments targeting TAMs by inhibiting TAM recruitment and differentiation, by regulating TAM polarization, and by blocking factors and pathways associated with the protumor function of TAMs. This comprehensive review presents recent research on TAMs in relation to prediction of poor outcomes, remodeling of the tumor immune microenvironment, and immunological targeted therapies.

  1. Research Progress on the Mechanism of Groundwater Arsenic Contamination Caused by Animal Feed Additives with Roxarsone%畜禽饲料添加洛克沙胂诱发地下水中砷污染的研究进展

    Institute of Scientific and Technical Information of China (English)

    李亚松; 张兆吉; 费宇红; 陈鸿汉

    2013-01-01

    The roxarsone can improve feed utilization,inhibit harmful bacteria and promote the growth,so it is widely used in livestook and poultry industry.However,most of them were excreted with animal feces and urine due to its low uptake,which can lead to arsenic contamination in soil and groundwater if improper handling appears.Recent years,the livestock and poultry industry has been rapidly developed,a large proportion has not harmless treatment for solid-liquid waste,but stack in open environment casually.The investigation on arsenic contamination in livestock and poultry industry,transformation and adsorption of roxarsone in environment,control of roxarsone contamination were reviewed in the study.%洛克沙胂具有提高饲料利用率、抑制有害菌和促进生长的作用,因此在畜禽养殖业中的应用较为广泛,然而由于其在动物体内吸收量极低,绝大部分随动物粪便和尿液排出体外,若处理不当会导致土壤和地下水环境出现砷污染现象.近年来,我国畜禽养殖业发展较为迅速,但是有些畜禽养殖区已经暴露出严重的砷污染问题.笔者对畜禽养殖砷污染调查研究、洛克沙肿在环境中的转化和吸附作用以及洛克沙胂污染的治理等方面进行了综述.

  2. Arsenic removal by lime softening

    DEFF Research Database (Denmark)

    Kaosol, T.; Suksaroj, C.; Bregnhøj, Henrik

    2002-01-01

    This paper focuses on the study of arsenic removal for drinking water by lime softening. The initial arsenic (V) concentration was 500 and 1,000 ug/L in synthetic groundwater. The experiments were performed as batch tests with varying lime dosages and mixing time. For the synthetic groundwater......, arsenic (V) removal increased with increasing lime dosage and mixing time, as well as with the resulting pH. The residual arsenic (V) in all cases was lower than the WHO guideline of 10 ug/L at pH higher than 11.5. Kinetic of arsenic (V) removal can be described by a first-order equation as C1 = C0*e......^-k*t. The relation between the constant (k value) and increasing lime dosage was found to be linear, described by k = 0.0034 (Dlime). The results support a theory from the literature that the arsenic (V) was removed by precipitation af Ca3(AsO4)2. The results obtained in the present study suggest that lime...

  3. NOK/STYK1 promotes the genesis and remodeling of blood and lymphatic vessels during tumor progression.

    Science.gov (United States)

    Liu, Yue; Li, Tianqi; Hu, Dan; Zhang, Shuping

    2016-09-01

    Previous studies have indicated that the overexpression of NOK, also named STYK1, led to tumorigenesis and metastasis. Here, we provide evidence that increased expression of NOK/STYK1 caused marked alterations in the overall and inner structures of tumors and substantially facilitates the genesis and remodeling of the blood and lymphatic vessels during tumor progression. In particular, NOK-expressed HeLa stable cells (HeLa-K) significantly enhanced tumor growth and metastasis in xenografted nude mice. Hematoxylin and eosin (HE) staining demonstrated that the tumor tissues generated by HeLa-K cells were much more ichorous and had more interspaces than those generated by control HeLa cells (HeLa-C). The fluorescent areas stained with cluster of differentiation 31 (CD31), a marker protein for blood vessels, appeared to be in different patterns. The total blood vessels, especially the ring patterns, within the tumors of the HeLa-K group were highly enriched compared with those in the HeLa-C group. NOK-HA was demonstrated to be well colocalized with CD31 in the wall of the tubular structures within tumor tissues. Interestingly, antibody staining of the lymphatic vessel endothelial hyaluronan receptor (LYVE-1) further revealed the increase in ring (oratretic strip-like) lymphatic vessels in either the peritumoral or intratumoral areas in the HeLa-K group compared with the HeLa-C group. Consistently, the analysis of human cancerous tissue also showed that NOK was highly expressed in the walls of tubular structures. Thus, our results reveal a novel tumorigenic function of NOK to mediate the genesis and remodeling of blood and lymphatic vessels during tumor progression.

  4. The pro-inflammatory peptide LL-37 promotes ovarian tumor progression through recruitment of multipotent mesenchymal stromal cells

    Science.gov (United States)

    Coffelt, Seth B.; Marini, Frank C.; Watson, Keri; Zwezdaryk, Kevin J.; Dembinski, Jennifer L.; LaMarca, Heather L.; Tomchuck, Suzanne L.; zu Bentrup, Kerstin Honer; Danka, Elizabeth S.; Henkle, Sarah L.; Scandurro, Aline B.

    2009-01-01

    Bone marrow-derived mesenchymal stem cells or multipotent mesenchymal stromal cells (MSCs) have been shown to engraft into the stroma of several tumor types, where they contribute to tumor progression and metastasis. However, the chemotactic signals mediating MSC migration to tumors remain poorly understood. Previous studies have shown that LL-37 (leucine, leucine-37), the C-terminal peptide of human cationic antimicrobial protein 18, stimulates the migration of various cell types and is overexpressed in ovarian, breast, and lung cancers. Although there is evidence to support a pro-tumorigenic role for LL-37, the function of the peptide in tumors remains unclear. Here, we demonstrate that neutralization of LL-37 in vivo significantly reduces the engraftment of MSCs into ovarian tumor xenografts, resulting in inhibition of tumor growth as well as disruption of the fibrovascular network. Migration and invasion experiments conducted in vitro indicated that the LL-37-mediated migration of MSCs to tumors likely occurs through formyl peptide receptor like-1. To assess the response of MSCs to the LL-37-rich tumor microenvironment, conditioned medium from LL-37-treated MSCs was assessed and found to contain increased levels of several cytokines and pro-angiogenic factors compared with controls, including IL-1 receptor antagonist, IL-6, IL-10, CCL5, VEGF, and matrix metalloproteinase-2. Similarly, Matrigel mixed with LL-37, MSCs, or the combination of the two resulted in a significant number of vascular channels in nude mice. These data indicate that LL-37 facilitates ovarian tumor progression through recruitment of progenitor cell populations to serve as pro-angiogenic factor-expressing tumor stromal cells. PMID:19234121

  5. Continuous taurocholic acid exposure promotes esophageal squamous cell carcinoma progression due to reduced cell loss resulting from enhanced vascular development.

    Directory of Open Access Journals (Sweden)

    Sho Sato

    Full Text Available BACKGROUND: Refluxogenic effects of smoking and alcohol abuse may be related to the risk of esophageal squamous cell carcinoma (ESCC. The present study attempts to clarify the effects of continuous taurocholic acid (TCA exposure, which is neither mutagenic nor genotoxic, on ESCC progression. METHODS: A squamous carcinoma cell line (ESCC-DR was established from a tumor induced in a rat model of gastroduodenal reflux. ESCC-DR cells were incubated with 2 mM TCA for ≥2 months. The effects of continuous TCA exposure were evaluated in vitro on cell morphology, growth, and invasion and in vivo on xenograft tumor growth in nude mice. Moreover, the mean level of secreted transforming growth factor (TGF-β1 and vascular endothelial growth factor (VEGF proteins in cell culture supernatants and mRNA synthesis of TGF-β1 and VEGF-A of ESCC cells were measured. The angiogenic potential was further examined by a migration assay using human umbilical vein endothelial cells (HUVECs. RESULTS: Continuous TCA exposure induced marked formation of filopodia in vitro. Expression levels of angiogenic factors were significantly higher in the cells treated with TCA than in control cells. Tumor xenografts derived from cells pre-exposed to TCA were larger and more vascularized than those derived from control cells. In addition, TCA exposure increased HUVEC migration. CONCLUSION: Continuous TCA exposure enhanced ESCC progression due to reduced cell loss in vivo. Cell loss was inhibited by TCA-induced vascular endothelial cell migration, which was mediated by TGF-β1 and VEGF-A released from ESCC cells.

  6. Aberrant promoter methylation and gene expression of H-cadherin gene is associated with tumor progression and recurrence in epithelial ovarian carcinoma

    Directory of Open Access Journals (Sweden)

    Rahul Bhagat

    2014-01-01

    Full Text Available Background: Loss of expression of cadherins by promoter hypermethylation has been described in many epithelial cancers, and it may play a role in tumor cell invasion and metastasis. Previously, we reported that E-cadherin gene is frequently methylated in epithelial ovarian cancer. Aim: The aim of this study was to compare the promoter hypermethylation of H-cadherin gene in ovarian epithelial neoplasms to better understand the role of epigenetic silencing in carcinogenesis. Materials and Methods: We examined the promoter methylation of the H-cadherin gene in 134 epithelial ovarian carcinomas (EOC, 23 low malignant potential (LMP tumors, 26 benign cystadenomas and 15 normal ovarian tissues. Methylation was investigated by methylation specific polymerase chain reaction (MSP and the results confirmed by bisulfite DNA sequencing. Relative gene expression of H-cadherin was done using quantitative reverse transcriptase PCR on 51 EOC cases, 9 LMP tumors, 7 benign cystadenomas with 5 normal ovarian tissues. Results: Aberrant methylation of H-cadherin was present in 20 of 134 (15% carcinoma cases, 2 of 23 (09% LMP tumors and 1 of 26 (4% benign cystadenomas. No methylation was observed in any of the normal ovarian tissues. The mRNA expression level of H-cadherin was significantly down-regulated in EOC and LMP tumors than the corresponding normal tissues, whereas the expression level was normal in benign cystadenomas. A significant correlation of H-cadherin promoter methylation was observed with reduced gene expression in EOC. The prevalence of H-cadherin methylation was associated significantly with stage, histopathological grade, and menopausal status of the patient. H-cadherin methylation also had significant association with recurrence and differentiation of tumor. Conclusion: Our findings suggest an association between H-cadherin methylation, tumor progression and recurrence in EOC.

  7. Arsenic exposure disrupts epigenetic regulation of SIRT1 in human keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    Herbert, Katharine J. [School of Health Sciences, University of Tasmania, Launceston, TAS 7250 (Australia); Holloway, Adele [Menzies Research Institute Tasmania, University of Tasmania, Hobart, TAS 7000 (Australia); Cook, Anthony L. [School of Health Sciences, University of Tasmania, Launceston, TAS 7250 (Australia); Chin, Suyin P. [Menzies Research Institute Tasmania, University of Tasmania, Hobart, TAS 7000 (Australia); Snow, Elizabeth T., E-mail: elizabeth.snow@utas.edu.au [School of Health Sciences, University of Tasmania, Launceston, TAS 7250 (Australia)

    2014-11-15

    Arsenic is an environmental toxin which increases skin cancer risk for exposed populations worldwide; however the underlying biomolecular mechanism for arsenic-induced carcinogenesis is complex and poorly defined. Recent investigations show that histone deacetylase and DNA methyltransferase activity is impaired, and epigenetic patterns of gene regulation are consistently altered in cancers associated with arsenic exposure. Expression of the histone deacetylase SIRT1 is altered in solid tumours and haematological malignancies; however its role in arsenic-induced pathology is unknown. In this study we investigated the effect of arsenic on epigenetic regulation of SIRT1 and its targeting microRNA, miR-34a in primary human keratinocytes. Acetylation of histone H4 at lysine 16 (H4K16) increased in keratinocytes exposed to 0.5 μM arsenite [As(III)]; and this was associated with chromatin remodelling at the miR-34a promoter. Moreover, although SIRT1 protein initially increased in these As(III)-exposed cells, after 24 days expression was not significantly different from untreated controls. Extended exposure to low-dose As(III) (0.5 μM; > 5 weeks) compromised the pattern of CpG methylation at SIRT1 and miR-34a gene promoters, and this was associated with altered expression for both genes. We have found that arsenic alters epigenetic regulation of SIRT1 expression via structural reorganisation of chromatin at the miR-34a gene promoter in the initial 24 h of exposure; and over time, through shifts in miR-34a and SIRT1 gene methylation. Taken together, this investigation demonstrates that arsenic produces cumulative disruptions to epigenetic regulation of miR-34a expression, and this is associated with impaired coordination of SIRT1 functional activity. - Highlights: • Submicromolar arsenic concentrations disrupt SIRT1 activity and expression in human keratinocytes. • Arsenic-induced chromatin remodelling at the miR-34a gene promoter is associated with hyperacetylation

  8. Approaches to Increase Arsenic Awareness in Bangladesh: An Evaluation of an Arsenic Education Program

    Science.gov (United States)

    George, Christine Marie; Factor-Litvak, Pam; Khan, Khalid; Islam, Tariqul; Singha, Ashit; Moon-Howard, Joyce; van Geen, Alexander; Graziano, Joseph H.

    2013-01-01

    The objective of this study was to design and evaluate a household-level arsenic education and well water arsenic testing intervention to increase arsenic awareness in Bangladesh. The authors randomly selected 1,000 study respondents located in 20 villages in Singair, Bangladesh. The main outcome was the change in knowledge of arsenic from…

  9. Arsenic uptake and metabolism in plants.

    Science.gov (United States)

    Zhao, F J; Ma, J F; Meharg, A A; McGrath, S P

    2009-03-01

    Arsenic (As) is an element that is nonessential for and toxic to plants. Arsenic contamination in the environment occurs in many regions, and, depending on environmental factors, its accumulation in food crops may pose a health risk to humans.Recent progress in understanding the mechanisms of As uptake and metabolism in plants is reviewed here. Arsenate is taken up by phosphate transporters. A number of the aquaporin nodulin26-like intrinsic proteins (NIPs) are able to transport arsenite,the predominant form of As in reducing environments. In rice (Oryza sativa), arsenite uptake shares the highly efficient silicon (Si) pathway of entry to root cells and efflux towards the xylem. In root cells arsenate is rapidly reduced to arsenite, which is effluxed to the external medium, complexed by thiol peptides or translocated to shoots. One type of arsenate reductase has been identified, but its in planta functions remain to be investigated. Some fern species in the Pteridaceae family are able to hyperaccumulate As in above-ground tissues. Hyperaccumulation appears to involve enhanced arsenate uptake, decreased arsenite-thiol complexation and arsenite efflux to the external medium, greatly enhanced xylem translocation of arsenite, and vacuolar sequestration of arsenite in fronds. Current knowledge gaps and future research directions are also identified.

  10. Annual Progress Report, Fiscal Year 1981.

    Science.gov (United States)

    1981-09-30

    Measurement of Serum, Zinc, Magnesium, Copper, Lead, Lithium and Arsenic During Pregnancy ........................... 171 Work Unit No. 81/44 (FY81,0...Patients will be studied before and during therapy, as well as during progression of disease. b. Patients with protein-losing nephropathies and those...Serial Measurement of Serum, Zinc, Magnesium, Copper, Lead, Lithium and Arsenic During Pregnancy. Start Date: Est Comp Date: Principal Investigator

  11. Annual Progress Report Fiscal Year 1983.

    Science.gov (United States)

    1983-09-30

    Measurement of Serum, Zinc, Magnesium, Copper, Lead, Lithium and Arsenic During Pregnancy ........................... 155 * Work Unit No. 81/44 (FY81,O...studied before and during therapy, as v,-I ,j ojrl:.- progression of disease. b. Patients with protein-losing nephropathies and those undergoing...Thomason General Hospital. (2) To establish normal mean levels of zinc, magnesium, copper, lead, lithium , and arsenic at various stages of pregnancy. (3) To

  12. Loss of Abhd5 Promotes Colorectal Tumor Development and Progression by Inducing Aerobic Glycolysis and Epithelial-Mesenchymal Transition

    Directory of Open Access Journals (Sweden)

    Juanjuan Ou

    2014-12-01

    Full Text Available How cancer cells shift metabolism to aerobic glycolysis is largely unknown. Here, we show that deficiency of α/β-hydrolase domain-containing 5 (Abhd5, an intracellular lipolytic activator that is also known as comparative gene identification 58 (CGI-58, promotes this metabolic shift and enhances malignancies of colorectal carcinomas (CRCs. Silencing of Abhd5 in normal fibroblasts induces malignant transformation. Intestine-specific knockout of Abhd5 in ApcMin/+ mice robustly increases tumorigenesis and malignant transformation of adenomatous polyps. In colon cancer cells, Abhd5 deficiency induces epithelial-mesenchymal transition by suppressing the AMPKα-p53 pathway, which is attributable to increased aerobic glycolysis. In human CRCs, Abhd5 expression falls substantially and correlates negatively with malignant features. Our findings link Abhd5 to CRC pathogenesis and suggest that cancer cells develop aerobic glycolysis by suppressing Abhd5-mediated intracellular lipolysis.

  13. The need for congressional action to finance arsenic reductions in drinking water.

    Science.gov (United States)

    Levine, Rebecca Leah

    2012-11-01

    Many public water systems in the U.S. are unsafe because the communities cannot afford to comply with the current 10 parts per billion (ppb) federal arsenic standard for drinking water. Communities unable to afford improvements remain vulnerable to adverse health effects associated with higher levels of arsenic exposure. Scientific and bipartisan political consensus exists that the arsenic standard should not be less stringent than 10 ppb, and new data suggest additional adverse health effects related to arsenic exposure through drinking water. Congress has failed to reauthorize the Drinking Water State Revolving Fund program to provide reliable funding to promote compliance and reduce the risk of adverse health effects. Congress's recent ad hoc appropriations do not allow long-term planning and ongoing monitoring and maintenance. Investing in water infrastructure will lower health care costs and create American jobs. Delaying necessary upgrades will only increase the costs of improvements over time.

  14. Phytoremediation of arsenic contaminated soil by arsenic accumulators: a three year study.

    Science.gov (United States)

    Raj, Anshita; Singh, Nandita

    2015-03-01

    To investigate whether phytoremediation can remove arsenic from the contaminated area, a study was conducted for three consecutive years to determine the efficiency of Pteris vittata, Adiantum capillus veneris, Christella dentata and Phragmites karka, on arsenic removal from the arsenic contaminated soil. Arsenic concentrations in the soil samples were analysed after harvesting in 2009, 2010 and 2011 at an interval of 6 months. Frond arsenic concentrations were also estimated in all the successive harvests. Fronds resulted in the greatest amount of arsenic removal. Root arsenic concentrations were analysed in the last harvest. Approximately 70 % of arsenic was removed by P. vittata which was recorded as the highest among the four plant species. However, 60 % of arsenic was removed by A. capillus veneris, 55.1 % by C. dentata and 56.1 % by P. karka of arsenic was removed from the contaminated soil in 3 years.

  15. Effect of organic matter amendment, arsenic amendment and water management regime on rice grain arsenic species.

    Science.gov (United States)

    Norton, Gareth J; Adomako, Eureka E; Deacon, Claire M; Carey, Anne-Marie; Price, Adam H; Meharg, Andrew A

    2013-06-01

    Arsenic accumulation in rice grain has been identified as a major problem in some regions of Asia. A study was conducted to investigate the effect of increased organic matter in the soil on the release of arsenic into soil pore water and accumulation of arsenic species within rice grain. It was observed that high concentrations of soil arsenic and organic matter caused a reduction in plant growth and delayed flowering time. Total grain arsenic accumulation was higher in the plants grown in high soil arsenic in combination with high organic matter, with an increase in the percentage of organic arsenic species observed. The results indicate that the application of organic matter should be done with caution in paddy soils which have high soil arsenic, as this may lead to an increase in accumulation of arsenic within rice grains. Results also confirm that flooding conditions substantially increase grain arsenic.

  16. Regeneration of Commercial SCR Catalysts: Probing the Existing Forms of Arsenic Oxide.

    Science.gov (United States)

    Li, Xiang; Li, Junhua; Peng, Yue; Si, Wenzhe; He, Xu; Hao, Jiming

    2015-08-18

    To investigate the poisoning and regeneration of SCR catalysts, fresh and arsenic-poisoned commercial V2O5-WO3/TiO2 catalysts are researched in the context of deactivation mechanisms and regeneration technology. The results indicate that the forms of arsenic oxide on the poisoned catalyst are related to the proportion of arsenic (As) on the catalyst. When the surface coverage of (V+W+As) is lower than 1, the trivalent arsenic species (As(III)) is the major component, and this species prefers to permeate into the bulk-phase channels. However, at high As concentrations, pentavalent arsenic species (As(IV)) cover the surface of the catalyst. Although both arsenic species lower the NOx conversion, they affect the formation of N2O differently. In particular, N2O production is limited when trivalent arsenic species predominate, which may be related to As2O3 clogging the pores of the catalyst. In contrast, the pentavalent arsenic oxide species (As2O5) possess several As-OH groups. These As-OH groups could not only enhance the ability of the catalyst to become reduced, but also provide several Brønsted acid sites with weak thermal stability that promote the formation of N2O. Finally, although our novel Ca(NO3)2-based regeneration method cannot completely remove As2O3 from the micropores of the catalyst, this approach can effectively wipe off surface arsenic oxides without a significant loss of the catalyst's active components.

  17. Phytoextraction by arsenic hyperaccumulator Pteris vittata L. from six arsenic-contaminated soils: Repeated harvests and arsenic redistribution

    Energy Technology Data Exchange (ETDEWEB)

    Gonzaga, Maria I.S.; Santos, Jorge A.G. [Department of Soil Chemistry, Universidade Federal da Bahia, Cruz das Almas, 44380000 (Brazil); Ma, Lena Q. [Soil and Water Science Department, University of Florida, 2169 McCarty Hall, Gainesville, FL 32611-0290 (United States)], E-mail: lqma@ifas.ufl.edu

    2008-07-15

    This greenhouse experiment evaluated arsenic removal by Pteris vittata and its effects on arsenic redistribution in soils. P. vittata grew in six arsenic-contaminated soils and its fronds were harvested and analyzed for arsenic in October, 2003, April, 2004, and October, 2004. The soil arsenic was separated into five fractions via sequential extraction. The ferns grew well and took up arsenic from all soils. Fern biomass ranged from 24.8 to 33.5 g plant{sup -1} after 4 months of growth but was reduced in the subsequent harvests. The frond arsenic concentrations ranged from 66 to 6,151 mg kg{sup -1}, 110 to 3,056 mg kg{sup -1}, and 162 to 2,139 mg kg{sup -1} from the first, second and third harvest, respectively. P. vittata reduced soil arsenic by 6.4-13% after three harvests. Arsenic in the soils was primarily associated with amorphous hydrous oxides (40-59%), which contributed the most to arsenic taken up by P. vittata (45-72%). It is possible to use P. vittata to remediate arsenic-contaminated soils by repeatedly harvesting its fronds. - Pteris vittata was effective in continuously removing arsenic from contaminated soils after three repeated harvests.

  18. Research Progress of "Warm-promoting Needle" in Recent Years%近年来"温通针法"研究概况

    Institute of Scientific and Technical Information of China (English)

    赵耀东; 韩豆瑛; 方晓丽

    2012-01-01

    We concluded research progress of "warm-promoting needle" in recent years from clinical and experimental study and pointed out that future study should adhere to the principle of "control, random, double-blind and repetitive" strictly and increase more cases, which could make the research more perfect.%从临床和实验研究两方面总结"温通针法"近年来的研究概况,指出"温通针法"今后的研究应该严格按照对照、随机、双盲、重复的原则,加大病例数并进行系统、深入的研究,才能使之更加完善.

  19. Arsenic in the aetiology of cancer.

    Science.gov (United States)

    Tapio, Soile; Grosche, Bernd

    2006-06-01

    Arsenic, one of the most significant hazards in the environment affecting millions of people around the world, is associated with several diseases including cancers of skin, lung, urinary bladder, kidney and liver. Groundwater contamination by arsenic is the main route of exposure. Inhalation of airborne arsenic or arsenic-contaminated dust is a common health problem in many ore mines. This review deals with the questions raised in the epidemiological studies such as the dose-response relationship, putative confounders and synergistic effects, and methods evaluating arsenic exposure. Furthermore, it describes the metabolic pathways of arsenic, and its biological modes of action. The role of arsenic in the development of cancer is elucidated in the context of combined epidemiological and biological studies. However, further analyses by means of molecular epidemiology are needed to improve the understanding of cancer aetiology induced by arsenic.

  20. RARE CASE REPORT OF CHRONIC ARSENIC POISONING

    OpenAIRE

    Mundle; Neelima; Sushrut; Yogesh; Shukan; Shalik; Siddharth

    2014-01-01

    Today, arsenic is primarily used in the produc tion of glass and semiconductors., Arsenic may be found as a water or food contaminant, particularly in shellfish and other seafood, and often contaminates fruits and vegetables, particularly rice

  1. Inorganic arsenic poisoning in pastured feeder lambs

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, H.A.; Crane, M.R.; Tomson, K.

    1971-01-01

    Clinical signs and necropsy findings in a group of feeder lambs were suggestive of inorganic arsenic poisoning. Source of exposure was established and toxic concentrations of arsenic were detected in the tissues. 13 references, 1 table.

  2. RARE CASE REPORT OF CHRONIC ARSENIC POISONING

    Directory of Open Access Journals (Sweden)

    Mundle

    2014-12-01

    Full Text Available Today, arsenic is primarily used in the produc tion of glass and semiconductors., Arsenic may be found as a water or food contaminant, particularly in shellfish and other seafood, and often contaminates fruits and vegetables, particularly rice

  3. HER family kinase domain mutations promote tumor progression and can predict response to treatment in human breast cancer

    KAUST Repository

    Boulbes, Delphine R.

    2014-11-11

    Resistance to HER2-targeted therapies remains a major obstacle in the treatment of HER2-overexpressing breast cancer. Understanding the molecular pathways that contribute to the development of drug resistance is needed to improve the clinical utility of novel agents, and to predict the success of targeted personalized therapy based on tumor-specific mutations. Little is known about the clinical significance of HER family mutations in breast cancer. Because mutations within HER1/EGFR are predictive of response to tyrosine kinase inhibitors (TKI) in lung cancer, we investigated whether mutations in HER family kinase domains are predictive of response to targeted therapy in HER2-overexpressing breast cancer. We sequenced the HER family kinase domains from 76 HER2-overexpressing invasive carcinomas and identified 12 missense variants. Patients whose tumors carried any of these mutations did not respond to HER2 directed therapy in the metastatic setting. We developed mutant cell lines and used structural analyses to determine whether changes in protein conformation could explain the lack of response to therapy. We also functionally studied all HER2 mutants and showed that they conferred an aggressive phenotype and altered effects of the TKI lapatinib. Our data demonstrate that mutations in the finely tuned HER kinase domains play a critical function in breast cancer progression and may serve as prognostic and predictive markers.

  4. Long non-coding RNA APTR promotes the activation of hepatic stellate cells and the progression of liver fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Fujun [Department of Gastroenterology, Jinshan Hospital of Fudan University, Jinshan, Shanghai, 201508 (China); Zheng, Jianjian [Wenzhou Key Laboratory of Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000 (China); Mao, Yuqing [Department of Gastroenterology, Jinshan Hospital of Fudan University, Jinshan, Shanghai, 201508 (China); Dong, Peihong [Department of Infectious Diseases, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000 (China); Li, Guojun [Department of Hepatology, Ningbo Yinzhou Second Hospital, Ningbo, 315000 (China); Lu, Zhongqiu [Department of Emergency, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000 (China); Guo, Chuanyong; Liu, Zhanju [Department of Gastroenterology, Shanghai Tenth People' s Hospital, Tongji University School of Medicine, Shanghai, 200072 (China); Fan, Xiaoming, E-mail: ktsqdph@163.com [Department of Gastroenterology, Jinshan Hospital of Fudan University, Jinshan, Shanghai, 201508 (China)

    2015-08-07

    In this study, we aimed at assessing a role of Alu-mediated p21 transcriptional regulator (APTR) in hepatofibrogenesis. APTR was upregulated in fibrotic liver samples and activated hepatic stellate cells (HSCs). Knockdown of APTR inhibited the activation of HSCs in vitro and mitigated the accumulation of collagen in vivo. Importantly, APTR silencing could abrogate TGF-β{sub 1}-induced upregulation of α-SMA in HSCs. In addition, inhibition of cell cycle and cell proliferation by APTR knockdown was attenuated by p21 siRNA1 in primary HSCs. Finally, serum APTR levels were increased in patients with liver cirrhosis, indicating a potential biomarker for liver cirrhosis. Collectively, evidence is proposed for a new biological role of APTR in hepatofibrogenesis. - Highlights: • APTR is upregulated in fibrotic liver tissues and activated HSCs. • APTR silencing inhibits HSC activation and the progression of liver fibrosis. • Antifibrotic effect of APTR silencing is achieved by increasing p21.

  5. Telephone-based motivational interviewing to promote physical activity and stage of change progression in older adults.

    Science.gov (United States)

    Lilienthal, Kaitlin R; Pignol, Anna Evans; Holm, Jeffrey E; Vogeltanz-Holm, Nancy

    2014-10-01

    This study examined the efficacy of motivational interviewing (MI) for increasing physical activity in aging adults. Eighty-six participants aged 55 years and older were randomly assigned to receive either four weekly sessions of telephone-based MI for increasing physical activity, or a healthy activity living guide (information only control). Changes from baseline weekly caloric expenditure from physical activity, self-efficacy for physical activity, and stage of change for physical activity were compared across groups at posttreatment and six months follow-up. Results indicated that MI participants had higher weekly caloric expenditures from physical activity at posttreatment, but not at six months follow-up; higher self-efficacy for physical activity at six months follow-up; and demonstrated greater stage of change progression across assessments. These findings support the use of telephone-based MI for increasing physical activity in older adults in the short-term. Future studies will need to determine if follow-up booster sessions increase long-term efficacy.

  6. CD147 promotes liver fibrosis progression via VEGF-A/VEGFR2 signalling-mediated cross-talk between hepatocytes and sinusoidal endothelial cells.

    Science.gov (United States)

    Yan, Zhaoyong; Qu, Kai; Zhang, Jing; Huang, Qichao; Qu, Ping; Xu, Xinsen; Yuan, Peng; Huang, Xiaojun; Shao, Yongping; Liu, Chang; Zhang, Hongxin; Xing, Jinliang

    2015-10-01

    Although previous evidence indicates close involvement of CD147 in the pathogenesis of liver fibrosis, the underlying molecular mechanisms and its therapeutic value remain largely unknown. In the present study, we investigated the biological roles of CD147 in liver fibrosis and assessed its therapeutic value as a target molecule in the CCl4-induced liver fibrosis mouse model. We found that CD147 was highly expressed in both hepatocytes and SECs (sinusoidal endothelial cells) in fibrotic liver tissues. Additionally, it was significantly associated with the fibrosis stage. TGF-β1 (transforming growth factor β1) was found to be mainly responsible for the up-regulation of CD147. Bioinformatic and experimental data suggest a functional link between CD147 expression and VEGF-A (vascular endothelial growth factor A)/VEGR-2 (VEGF receptor 2) signalling-mediated angiogenesis in fibrotic liver tissues. Furthermore, we observed that the CD147-induced activation of the PI3K (phosphoinositide 3-kinase)/Akt signalling pathway promotes the production of VEGF-A in hepatocytes and expression of VEGFR-2 in SECs, which was found to enhance the angiogenic capability of SECs. Finally, our data indicate that blocking of CD147 using an mAb (monoclonal antibody) attenuated liver fibrosis progression via inhibition of VEGF-A/VEGFR-2 signalling and subsequent amelioration of microvascular abnormality in the CCl4-induced mouse model. Our findings suggest a novel functional mechanism that CD147 may promote liver fibrosis progression via inducing the VEGF-A/VEGFR-2 signalling pathway-mediated cross-talk between hepatocytes and SECs. New strategies based on the intervention of CD147 can be expected for prevention of liver fibrosis.

  7. Insights into arsenic multi-operons expression and arsenic resistance mechanisms in Rhodopseudomonas palustris CGA009

    OpenAIRE

    Chungui eZhao; Yi eZhang; Zhuhua eChan; Shicheng eChen; Suping eYang

    2015-01-01

    Arsenic (As) is widespread in the environment and causes numerous health problems. Rhodopseudomonas palustris has been regarded as a good model organism for studying arsenic detoxification since it was first demonstrated to methylate environmental arsenic by conversion to soluble or gaseous methylated species. However, the detailed arsenic resistance mechanisms remain unknown though there are at least three arsenic-resistance operons (ars1, ars2 and ars3) in R. palustris. In this study, we i...

  8. Attenuation of arsenic in a karst subterranean stream and correlation with geochemical factors: a case study at Lihu, South China.

    Science.gov (United States)

    Zhang, Liankai; Yang, Hui; Tang, Jiansheng; Qin, Xiaoqun; Yu, Au Yik

    2014-11-01

    Arsenic (As) pollutants generated by human activities in karst areas flow into subterranean streams and contaminate groundwater easily because of the unique hydrogeological characteristics of karst areas. To elucidate the reaction mechanisms of arsenic in karst subterranean streams, physical-chemical analysis was conducted by an inductively coupled plasma mass spectrometer and an X-ray fluorescence spectrometer. The results show that inorganic species account for most of the total arsenic, whereas organic arsenic is not detected or occurs in infinitesimal amounts. As(III) accounts for 51.0%±9.9% of the total inorganic arsenic. Arsenic attenuation occurs and the attenuation rates of total As, As(III) and As(V) in the Lihu subterranean stream are 51%, 36% and 59%, respectively. To fully explain the main geochemical factors influencing arsenic attenuation, SPSS 13.0 and CANOCO 4.5 bundled with CanoDraw for Windows were used for simple statistical analysis and redundancy analysis (RDA). Eight main factors, i.e., sediment iron (SFe), sediment aluminum (SAl), sediment calcium (SCa), sediment organic matter (SOM), sediment manganese (SMn), water calcium (WCa(2+)), water magnesium (WMg(2+)), and water bicarbonate ion (WHCO3(-)) were extracted from thirteen indicators. Their impacts on arsenic content rank as: SFe>SCa>WCa(2+)>SAl>WHCO3(-)>SMn>SOM>WMg(2+). Of these factors, SFe, SAl, SCa, SOM, SMn, WMg(2+) and WCa(2+) promote arsenic attenuation, whereas WHCO3(-) inhibits it. Further investigation revealed that the redox potential (Eh) and pH are adverse to arsenic removal. The dramatic distinction between karst and non-karst terrain is that calcium and bicarbonate are the primary factors influencing arsenic migration in karst areas due to the high calcium concentration and alkalinity of karst water.

  9. Arsenic bioavailability in soils before and after soil washing: the use of Escherichia coli whole-cell bioreporters.

    Science.gov (United States)

    Yoon, Youngdae; Kang, Yerin; Chae, Yooeun; Kim, Sunghoon; Lee, Youngshim; Jeong, Seung-Woo; An, Youn-Joo

    2016-02-01

    We investigated the quantification of bioavailable arsenic in contaminated soils and evaluation of soil-washing processes in the aspect of bioavailability using a novel bacterial bioreporter developed in present study. The whole-cell bioreporter (WCB) was genetically engineered by fusing the promoter of nik operon from Escherichia coli and green fluorescent protein as a sensing domain and reporter domain. Among eight well-known hazardous heavy metals and metalloid, this system responded specifically to arsenic, thereby inferring association of As(III) with NikR inhibits the repression. Moreover, the response was proportional to the concentration of As(III), thereby it was capable to determine the amount of bioavailable arsenic quantitatively in contaminated soils. The bioavailable portion of arsenic was 5.9 (3.46-10.96) and 0.9 (0.27-1.74) % of total from amended and site soils, respectively, suggesting the bioavailability of arsenic in soils was related to the soil properties and duration of aging. On the other hand, only 1.37 (0.21-2.97) % of total arsenic was extracted into soil solutions and 19.88 (11.86-28.27) % of arsenic in soil solution was bioavailable. This result showed that the soluble arsenic is not all bioavailable and most of bioavailable arsenic in soils is water non-extractable. In addition, the bioavailable arsenic was increased after soil-washing while total amount was decreased, thereby suggesting the soil-washing processes release arsenic associated with soil materials to be bioavailable. Therefore, it would be valuable to have a tool to assess bioavailability and the bioavailability should be taken into consideration for soil remediation plans.

  10. miR-125b can enhance skin tumor initiation and promote malignant progression by repressing differentiation and prolonging cell survival.

    Science.gov (United States)

    Zhang, Liang; Ge, Yejing; Fuchs, Elaine

    2014-11-15

    Previously, we identified miR-125b as a key regulator of the undifferentiated state of hair follicle stem cells. Here, we show that in both mice and humans, miR-125b is abundantly expressed, particularly at early stages of malignant progression to squamous cell carcinoma (SCC), the second most prevalent cancer worldwide. Moreover, when elevated in normal murine epidermis, miR-125b promotes tumor initiation and contributes to malignant progression. We further show that miR-125b can confer "oncomiR addiction" in early stage malignant progenitors by delaying their differentiation and favoring an SCC cancer stem cell (CSC)-like transcriptional program. To understand how, we systematically identified and validated miR125b targets that are specifically associated with tumors that are dependent on miR-125b. Through molecular and genetic analysis of these targets, we uncovered new insights underlying miR-125b's oncogenic function. Specifically, we show that, on the one hand, mir-125b directly represses stress-responsive MAP kinase genes and associated signaling. On the other hand, it indirectly prolongs activated (phosphorylated) EGFR signaling by repressing Vps4b (vacuolar protein-sorting 4 homolog B), encoding a protein implicated in negatively regulating the endosomal sorting complexes that are necessary for the recycling of active EGFR. Together, these findings illuminate miR-125b as an important microRNA regulator that is shared between normal skin progenitors and their early malignant counterparts.

  11. Association of Myxovirus Resistance Gene Promoter Polymorphism with Response to Combined Interferon Treatment and Progression of Liver Disease in Chronic HCV Egyptian Patients.

    Science.gov (United States)

    Bader El Din, Noha Gamal; Salum, Ghada M; Anany, Mohamed A; Ibrahim, Marwa Khalil; Dawood, Reham Mohamed; Zayed, Naglaa; El Abd, Yasmine S; El-Shenawy, Reem; El Awady, Mostafa K

    2015-08-01

    To evaluate the frequency of single-nucleotide polymorphism at the -88 myxovirus resistance (MxA) gene promoter region in relation to the status of hepatitis C virus (HCV) progression and response to combined interferon (IFN) in chronic HCV Egyptian patients. One hundred ten subjects were enrolled in the study; 60 HCV genotype 4-infected patients who underwent combined IFN therapy and 50 healthy individuals. All subjects were genotyped for -88 MxA polymorphism by the restriction fragment length polymorphism technique. There was an increasing trend of response to combined IFN treatment as 34.9% of GG, 64.3% of GT, and 66.7% of TT genotypes were sustained responders (P=0.05). The T allele was significantly affecting the response rate more than G allele (P=0.032). Moreover, the hepatic fibrosis score and hepatitis activity were higher in GG genotypes compared with the GT and TT genotypes. The multivariate analysis showed that the MxA GG genotype was an independent factor increasing the no response to IFN therapy (P=0.04, odds ratio [OR] 3.822, 95% confidence interval [CI] 1.056-11.092), also MxA G allele (P=0.0372, OR 2.905, 95% CI 1.066-7.919). MxA -88 polymorphism might be a potential biomarker to predict response to IFN and disease progression in chronic HCV-infected patients.

  12. Intra- and Extra-Cellular Events Related to Altered Glycosylation of MUC1 Promote Chronic Inflammation, Tumor Progression, Invasion, and Metastasis

    Directory of Open Access Journals (Sweden)

    Sandra Cascio

    2016-10-01

    Full Text Available Altered glycosylation of mucin 1 (MUC1 on tumor cells compared to normal epithelial cells was previously identified as an important antigenic modification recognized by the immune system in the process of tumor immunosurveillance. This tumor form of MUC1 is considered a viable target for cancer immunotherapy. The importance of altered MUC1 glycosylation extends also to its role as a promoter of chronic inflammatory conditions that lead to malignant transformation and cancer progression. We review here what is known about the role of specific cancer-associated glycans on MUC1 in protein-protein interactions and intracellular signaling in cancer cells and in their adhesion to each other and the tumor stroma. The tumor form of MUC1 also creates a different landscape of inflammatory cells in the tumor microenvironment by controlling the recruitment of inflammatory cells, establishing specific interactions with dendritic cells (DCs and macrophages, and facilitating tumor escape from the immune system. Through multiple types of short glycans simultaneously present in tumors, MUC1 acquires multiple oncogenic properties that control tumor development, progression, and metastasis at different steps of the process of carcinogenesis.

  13. FGF-1/-3/FGFR4 signaling in cancer-associated fibroblasts promotes tumor progression in colon cancer through Erk and MMP-7.

    Science.gov (United States)

    Bai, Yu-Pan; Shang, Kun; Chen, Huan; Ding, Fei; Wang, Zhen; Liang, Chen; Xu, Ye; Sun, Meng-Hong; Li, Ying-Yi

    2015-10-01

    Cancer-associated fibroblasts (CAFs), as the activated fibroblasts in the tumor stroma, are important modifiers of tumour progression. In the present study, we observed that azoxymethane and dextran sodium sulfate treatments induced increasingly severe colorectal mucosal inflammation and the intratumoural accumulation of CAFs. Fibroblast growth factor (FGF)-1 and FGF-3 were detected in infiltrating cells, and FGFR4, the specific receptor for FGF-1 and FGF-3, was detected in colon cancer tissues. The phosphorylation of FGFR4 enhanced the production of metalloproteinase (MMP)-7 and mitogen-activated protein kinase kinase (Mek)/extracellular signal-regulated kinase (Erk), which was accompanied by excessive vessel generation and cell proliferation. Moreover, we separated CAFs, pericarcinoma fibroblasts (PFs), and normal fibroblasts (NFs) from human colon tissue specimens to characterize the function of CAFs. We observed that CAFs secrete more FGF-1/-3 than NFs and PFs and promote cancer cell growth and angiogenesis through the activation of FGFR4, which is followed by the activation of Mek/Erk and the modulation of MMP-7 expression. The administration of FGF-1/-3-neutralizing antibodies or the treatment of cells with FGFR4 siRNA or the FGFR4 inhibitor PD173074 markedly suppressed colon cancer cell proliferation and neovascularization. These observations suggest a crucial role for CAFs and FGF signaling in the initiation and progression of colorectal cancer. The inhibition of the FGF signaling pathway may be a useful strategy for the treatment of colon cancer.

  14. ARSENIC SEPARATION FROM WATER USING ZEOLITES

    Science.gov (United States)

    Arsenic is known to be a hazardous contaminant in drinking water. The presence of arsenic in water supplies has been linked to arsenical dermatosis and skin cancer . Zeolites are well known for their ion exchange capacities. In the present work, the potential use of a variety of ...

  15. Arsenic - Multiple Languages: MedlinePlus

    Science.gov (United States)

    ... Are Here: Home → Multiple Languages → All Health Topics → Arsenic URL of this page: https://medlineplus.gov/languages/arsenic.html Other topics A-Z A B C ... V W XYZ List of All Topics All Arsenic - Multiple Languages To use the sharing features on ...

  16. 21 CFR 556.60 - Arsenic.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Arsenic. 556.60 Section 556.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND... New Animal Drugs § 556.60 Arsenic. Tolerances for total residues of combined arsenic (calculated as...

  17. Upregulation of long non-coding RNA PRNCR1 in colorectal cancer promotes cell proliferation and cell cycle progression.

    Science.gov (United States)

    Yang, Liu; Qiu, Mantang; Xu, Youtao; Wang, Jie; Zheng, Yanyan; Li, Ming; Xu, Lin; Yin, Rong

    2016-01-01

    Colorectal cancer (CRC) is one of the most common cancers worldwide. Long non-coding RNAs (lncRNAs) have been confirmed to play a critical regulatory role in various biological processes including carcinogenesis, which indicates that lncRNAs are valuable biomarkers and therapeutic targets. The novel lncRNA prostate cancer non-coding RNA 1 (PRNCR1) is located in the susceptible genomic area of CRC, however the functional role of PRNCR1 remains unknown. Thus, we aimed to investigate the clinical significance and biological function of PRNCR1 in CRC. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to assess the expression profile of PRNCR1 in CRC tissues and cell lines. An antisense oligonucleotide (ASO) was designed to knock down PRNCR1. In a cohort of 63 patients, PRNCR1 was significantly overexpressed in CRC tissues compared with the expression in adjacent tissues, with an average fold increase of 10.55 (P=0.006). Additionally, a high level of PRNCR1 was associated with large tumor volume (Pline (FHC), PRNCR1 was upregulated in most CRC cell lines (HCT116, SW480, LoVo and HT-29). After knockdown of PRNCR1 by ASO, CRC cell proliferation ability was significantly inhibited. We further found that PRNCR1 knockdown induced cell cycle arrest in the G0/G1 phase and a significant decrease in the proportion of cells in the S phases. In contrast, PRNCR1 knockdown did not affect cell apoptosis or invasive ability. Hence, these data indicate that PRNCR1 promotes the proliferation of CRC cells and is a potential oncogene of CRC.

  18. Variability in the precore and core promoter regions of HBV strains in Morocco: characterization and impact on liver disease progression.

    Directory of Open Access Journals (Sweden)

    Bouchra Kitab

    Full Text Available BACKGROUND: Hepatitis B virus (HBV is one of the most common human pathogens that cause aggressive hepatitis and advanced liver disease (AdLD, including liver cirrhosis and Hepatocellular Carcinoma. The persistence of active HBV replication and liver damage after the loss of hepatitis B e antigen (HBeAg has been frequently associated with mutations in the pre-core (pre-C and core promoter (CP regions of HBV genome that abolish or reduce HBeAg expression. The purpose of this study was to assess the prevalence of pre-C and CP mutations and their impact on the subsequent course of liver disease in Morocco. METHODS/PRINCIPAL FINDINGS: A cohort of 186 patients with HBeAg-negative chronic HBV infection was studied (81 inactive carriers, 69 with active chronic hepatitis, 36 with AdLD. Pre-C and CP mutations were analyzed by PCR-direct sequencing method. The pre-C stop codon G1896A mutation was the most frequent (83.9% and was associated with a lower risk of AdLD development (OR, 0.4; 95% CI, 0.15-1.04; p = 0.04. HBV-DNA levels in patients with G1896A were not significantly different from the other patients carrying wild-type strains (p = 0.84. CP mutations C1653T, T1753V, A1762T/G1764A, and C1766T/T1768A were associated with higher HBV-DNA level and increased liver disease severity. Multiple logistic regression analysis showed that older age (≥ 40 years, male sex, high viral load (>4.3 log(10 IU/mL and CP mutations C1653T, T1753V, A1762T/G1764A, and C1766T/T1768A were independent risk factors for AdLD development. Combination of these mutations was significantly associated with AdLD (OR, 7.52; 95% CI, 4.8-8; p<0.0001. CONCLUSIONS: This study shows for the first time the association of HBV viral load and CP mutations with the severity of liver disease in Moroccan HBV chronic carriers. The examination of CP mutations alone or in combination could be helpful for prediction of the clinical outcome.

  19. Arsenic – Poison or medicine?

    Directory of Open Access Journals (Sweden)

    Karolina Kulik-Kupka

    2016-04-01

    Full Text Available Arsenic (As is commonly known as a poison. Only a few people know that As has also been widely used in medicine. In the past years As and its compounds were used as a medicine for the treatment of such diseases as diabetes, psoriasis, syphilis, skin ulcers and joint diseases. Nowadays As is also used especially in the treatment of patients with acute promyelocytic leukemia. The International Agency for Research on Cancer (IARC has recognized arsenic as an element with carcinogenic effect evidenced by epidemiological studies, but as previously mentioned it is also used in the treatment of neoplastic diseases. This underlines the specificity of the arsenic effects. Arsenic occurs widely in the natural environment, for example, it is present in soil and water, which contributes to its migration to food products. Long exposure to this element may lead to liver damages and also to changes in myocardium. Bearing in mind that such serious health problems can occur, monitoring of the As presence in the environmental media plays a very important role. In addition, the occupational risk of As exposure in the workplace should be identified and checked. Also the standards for As presence in food should be established. This paper presents a review of the 2015 publications based on the Medical database like PubMed and Polish Medical Bibliography. It includes the most important information about arsenic in both forms, poison and medicine. Med Pr 2016;67(1:89–96

  20. Stress proteins induced by arsenic.

    Science.gov (United States)

    Del Razo, L M; Quintanilla-Vega, B; Brambila-Colombres, E; Calderón-Aranda, E S; Manno, M; Albores, A

    2001-12-01

    The elevated expression of stress proteins is considered to be a universal response to adverse conditions, representing a potential mechanism of cellular defense against disease and a potential target for novel therapeutics. Exposure to arsenicals either in vitro or in vivo in a variety of model systems has been shown to cause the induction of a number of the major stress protein families such as heat shock proteins (Hsp). Among them are members with low molecular weight, such as metallotionein and ubiquitin, as well as ones with masses of 27, 32, 60, 70, 90, and 110 kDa. In most of the cases, the induction of stress proteins depends on the capacity of the arsenical to reach the target, its valence, and the type of exposure, arsenite being the biggest inducer of most Hsp in several organs and systems. Hsp induction is a rapid dose-dependent response (1-8 h) to the acute exposure to arsenite. Thus, the stress response appears to be useful to monitor the sublethal toxicity resulting from a single exposure to arsenite. The present paper offers a critical review of the capacity of arsenicals to modulate the expression and/or accumulation of stress proteins. The physiological consequences of the arsenic-induced stress and its usefulness in monitoring effects resulting from arsenic exposure in humans and other organisms are discussed.

  1. Arsenic in groundwaters in the Northern Appalachian Mountain belt: a review of patterns and processes.

    Science.gov (United States)

    Peters, Stephen C

    2008-07-29

    Naturally occurring arsenic in the bedrock of the Northern Appalachian Mountain belt was first recognized in the late 19th century. The knowledge of the behavior of arsenic in groundwater in this region has lagged behind nearly a century, with the popular press reporting on local studies in the early 1980s, and most peer-reviewed research articles on regional patterns conducted and written in the late 1990s and early 2000s. Research reports have shown that within this high arsenic region, between 6% and 22% of households using private drinking water wells contain arsenic in excess of 10 microg/L, the United States Environmental Protection Agency's maximum contaminant level. In nearly all reports, arsenic in drinking water was derived from naturally occurring geologic sources, typically arsenopyrite, substituted sulfides such as arsenian pyrite, and nanoscale minerals such as westerveldite. In most studies, arsenic concentrations in groundwater were controlled by pH dependent adsorption to mineral surfaces, most commonly iron oxide minerals. In some cases, reductive dissolution of iron minerals has been shown to increase arsenic concentrations in groundwater, more commonly associated with anthropogenic activities such as landfills. Evidence of nitrate reduction promoting the presence of arsenic(V) and iron(III) minerals in anoxic environments has been shown to occur in surface waters, and in this manuscript we show this process perhaps applies to groundwater. The geologic explanation for the high arsenic region in the Northern Appalachian Mountain belt is most likely the crustal recycling of arsenic as an incompatible element during tectonic activity. Accretion of multiple terranes, in particular Avalonia and the Central Maine Terrane of New England appear to be connected to the presence of high concentrations of arsenic. Continued tectonic activity and recycling of these older terranes may also be responsible for the high arsenic observed in the Triassic rift

  2. Mineral resource of the month: arsenic

    Science.gov (United States)

    Brooks, William E.

    2008-01-01

    Arsenic has a long and varied history: Although it was not isolated as an element until the 13th century, it was known to the ancient Chinese, Egyptians and Greeks in compound form in the minerals arsenopyrite, realgar and orpiment. In the 1400s, “Scheele’s Green” was first used as an arsenic pigment in wallpaper, and leached arsenic from wallpaper may have contributed to Napoleon’s death in 1821. The 1940s play and later movie, Arsenic and Old Lace, dramatizes the metal’s more sinister role. Arsenic continues to be an important mineral commodity with many modern applications.

  3. Introducing Simple Detection of Bioavailable Arsenic at Rafaela (Santa Fe Province, Argentina) Using the ARSOlux Biosensor.

    Science.gov (United States)

    Siegfried, Konrad; Hahn-Tomer, Sonja; Koelsch, Andreas; Osterwalder, Eva; Mattusch, Juergen; Staerk, Hans-Joachim; Meichtry, Jorge M; De Seta, Graciela E; Reina, Fernando D; Panigatti, Cecilia; Litter, Marta I; Harms, Hauke

    2015-05-21

    Numerous articles have reported the occurrence of arsenic in drinking water in Argentina, and the resulting health effects in severely affected regions of the country. Arsenic in drinking water in Argentina is largely naturally occurring due to elevated background content of the metalloid in volcanic sediments, although, in some regions, mining can contribute. While the origin of arsenic release has been discussed extensively, the problem of drinking water contamination has not yet been solved. One key step in progress towards mitigation of problems related with the consumption of As-containing water is the availability of simple detection tools. A chemical test kit and the ARSOlux biosensor were evaluated as simple analytical tools for field measurements of arsenic in the groundwater of Rafaela (Santa Fe, Argentina), and the results were compared with ICP-MS and HPLC-ICP-MS measurements. A survey of the groundwater chemistry was performed to evaluate possible interferences with the field tests. The results showed that the ARSOlux biosensor performed better than the chemical field test, that the predominant species of arsenic in the study area was arsenate and that arsenic concentration in the studied samples had a positive correlation with fluoride and vanadium, and a negative one with calcium and iron.

  4. Introducing Simple Detection of Bioavailable Arsenic at Rafaela (Santa Fe Province, Argentina Using the ARSOlux Biosensor

    Directory of Open Access Journals (Sweden)

    Konrad Siegfried

    2015-05-01

    Full Text Available Numerous articles have reported the occurrence of arsenic in drinking water in Argentina, and the resulting health effects in severely affected regions of the country. Arsenic in drinking water in Argentina is largely naturally occurring due to elevated background content of the metalloid in volcanic sediments, although, in some regions, mining can contribute. While the origin of arsenic release has been discussed extensively, the problem of drinking water contamination has not yet been solved. One key step in progress towards mitigation of problems related with the consumption of As-containing water is the availability of simple detection tools. A chemical test kit and the ARSOlux biosensor were evaluated as simple analytical tools for field measurements of arsenic in the groundwater of Rafaela (Santa Fe, Argentina, and the results were compared with ICP-MS and HPLC-ICP-MS measurements. A survey of the groundwater chemistry was performed to evaluate possible interferences with the field tests. The results showed that the ARSOlux biosensor performed better than the chemical field test, that the predominant species of arsenic in the study area was arsenate and that arsenic concentration in the studied samples had a positive correlation with fluoride and vanadium, and a negative one with calcium and iron.

  5. Introducing Simple Detection of Bioavailable Arsenic at Rafaela (Santa Fe Province, Argentina) Using the ARSOlux Biosensor

    Science.gov (United States)

    Siegfried, Konrad; Hahn-Tomer, Sonja; Koelsch, Andreas; Osterwalder, Eva; Mattusch, Juergen; Staerk, Hans-Joachim; Meichtry, Jorge M.; De Seta, Graciela E.; Reina, Fernando D.; Panigatti, Cecilia; Litter, Marta I.; Harms, Hauke

    2015-01-01

    Numerous articles have reported the occurrence of arsenic in drinking water in Argentina, and the resulting health effects in severely affected regions of the country. Arsenic in drinking water in Argentina is largely naturally occurring due to elevated background content of the metalloid in volcanic sediments, although, in some regions, mining can contribute. While the origin of arsenic release has been discussed extensively, the problem of drinking water contamination has not yet been solved. One key step in progress towards mitigation of problems related with the consumption of As-containing water is the availability of simple detection tools. A chemical test kit and the ARSOlux biosensor were evaluated as simple analytical tools for field measurements of arsenic in the groundwater of Rafaela (Santa Fe, Argentina), and the results were compared with ICP-MS and HPLC-ICP-MS measurements. A survey of the groundwater chemistry was performed to evaluate possible interferences with the field tests. The results showed that the ARSOlux biosensor performed better than the chemical field test, that the predominant species of arsenic in the study area was arsenate and that arsenic concentration in the studied samples had a positive correlation with fluoride and vanadium, and a negative one with calcium and iron. PMID:26006123

  6. Mechanisms to cope with arsenic or cadmium excess in plants.

    Science.gov (United States)

    Verbruggen, Nathalie; Hermans, Christian; Schat, Henk

    2009-06-01

    The metalloid arsenic and the heavy metal cadmium have no demonstrated biological function in plants. Both elements are highly toxic and of major concern with respect to their accumulation in soils, in the food-chain or in drinking water. Arsenate is taken up by phosphate transporters and rapidly reduced to arsenite, As(III). In reducing environments, As(III) is taken up by aquaporin nodulin 26-like intrinsic proteins. Cd(2+) enters the root via essential metal uptake systems. As(III) and Cd(2+) share some similarity between their toxicology and sequestration machineries. Recent progress in understanding the mechanisms of As and Cd uptake and detoxification is presented, including the elucidation of why rice takes up so much arsenic from soil and of mechanisms of As and Cd hypertolerance.

  7. Arsenic mobility in contaminated lake sediments

    Energy Technology Data Exchange (ETDEWEB)

    Nikolaidis, Nikolaos P.; Dobbs, Gregory M.; Chen, Jing; Lackovic, Jeffrey

    2004-06-01

    An arsenic contaminated lake sediment near a landfill in Maine was used to characterize the geochemistry of arsenic and assess the influence of environmental conditions on its mobility. A kinetic model was developed to simulate the leaching ability of arsenic in lake sediments under different environmental conditions. The HM1D chemical transport model was used to model the column experiments and determine the rates of arsenic mobility from the sediment. Laboratory studies provided the information to construct a conceptual model to demonstrate the mobility of arsenic in the lake sediment. The leaching ability of arsenic in lake sediments greatly depends on the flow conditions of ground water and the geochemistry of the sediments. Large amounts of arsenic were tightly bound to the sediments. The amount of arsenic leaching out of the sediment to the water column was substantially decreased due to iron/arsenic co-precipitation at the water-sediment interface. Overall, it was found that arsenic greatly accumulated at the ground water/lake interface and it formed insoluble precipitates. - Arsenic accumulates at the ground water/lake interface, where it forms insoluble precipitates.

  8. Arsenic-cadmium interaction in rats.

    Science.gov (United States)

    Díaz-Barriga, F; Llamas, E; Mejía, J J; Carrizales, L; Santoyo, M E; Vega-Vega, L; Yáñez, L

    1990-11-01

    Simultaneous exposure to cadmium and arsenic is highly probable in the urban area of San Luis Potosi, Mexico due to common localization of copper and zinc smelters. Therefore, in this work, rats were intraperitoneally exposed either to cadmium or arsenic alone, or simultaneously to both metals. The effects of these treatments on three different toxicological parameters were studied. Cadmium modified the LD50 of arsenic and conversely arsenic modified the LD50 for cadmium. At the histopathological level, arsenic appeared to protect against the cadmium effects, especially on testes. This protective effect seemed to be related to the glutathione levels found in this tissue: rats exposed to both arsenic and cadmium, presented glutathione values intermediate to those observed after exposure to either metal alone; arsenic had the highest value and cadmium the lowest. In liver, rats exposed to arsenic, cadmium or arsenic and cadmium, presented glutathione values below those in the saline group, with the lowest value corresponding to the arsenic and cadmium treatment. The results appear to support the proposed interaction between arsenic and cadmium and coexposure to both metals seems to alter certain effects produced by either metal alone.

  9. Knowledge building insights on biomarkers of arsenic toxicity to keratinocytes and melanocytes.

    Science.gov (United States)

    Isokpehi, Raphael D; Udensi, Udensi K; Anyanwu, Matthew N; Mbah, Andreas N; Johnson, Matilda O; Edusei, Kafui; Bauer, Michael A; Hall, Roger A; Awofolu, Omotayo R

    2012-01-01

    Exposure to inorganic arsenic induces skin cancer and abnormal pigmentation in susceptible humans. High-throughput gene transcription assays such as DNA microarrays allow for the identification of biological pathways affected by arsenic that lead to initiation and progression of skin cancer and abnormal pigmentation. The overall purpose of the reported research was to determine knowledge building insights on biomarker genes for arsenic toxicity to human epidermal cells by integrating a collection of gene lists annotated with biological information. The information sets included toxicogenomics gene-chemical interaction; enzymes encoded in the human genome; enriched biological information associated with genes; environmentally relevant gene sequence variation; and effects of non-synonymous single nucleotide polymorphisms (SNPs) on protein function. Molecular network construction for arsenic upregulated genes TNFSF18 (tumor necrosis factor [ligand] superfamily member 18) and IL1R2 (interleukin 1 Receptor, type 2) revealed subnetwork interconnections to E2F4, an oncogenic transcription factor, predominantly expressed at the onset of keratinocyte differentiation. Visual analytics integration of gene information sources helped identify RAC1, a GTP binding protein, and TFRC, an iron uptake protein as prioritized arsenic-perturbed protein targets for biological processes leading to skin hyperpigmentation. RAC1 regulates the formation of dendrites that transfer melanin from melanocytes to neighboring keratinocytes. Increased melanocyte dendricity is correlated with hyperpigmentation. TFRC is a key determinant of the amount and location of iron in the epidermis. Aberrant TFRC expression could impair cutaneous iron metabolism leading to abnormal pigmentation seen in some humans exposed to arsenicals. The reported findings contribute to insights on how arsenic could impair the function of genes and biological pathways in epidermal cells. Finally, we developed visual analytics

  10. Remediation of arsenic contaminated soil by coupling oxalate washing with subsequent ZVI/Air treatment.

    Science.gov (United States)

    Cao, Menghua; Ye, Yuanyao; Chen, Jing; Lu, Xiaohua

    2016-02-01

    The application of a novel coupled process with oxalate washing and subsequent zero-valent iron (ZVI)/Air treatment for remediation of arsenic contaminated soil was investigated in the present study. Oxalate is biodegradable and widely present in the environment. With addition of 0.1 mol L(-1) oxalate under circumneutral condition, 83.7% and 52.6% of arsenic could be removed from a spiked kaolin and an actual contaminated soil respectively. Much more oxalate adsorption on the actual soil was attributed to the higher soil organic matter and clay content. Interestingly, oxalate retained in the washing effluent could act as an organic ligand to promote the oxidation efficiency of ZVI/Air at near neutral pH. Compared with the absence of oxalate, much more As(III) was oxidized. Arsenic was effectively adsorbed on iron (hydr)oxides as the consumption of oxalate and the increase of pH value. For the actual soil washing effluent, about 94.9% of total arsenic was removed after 120 min's treatment without pH adjustment. It has been demonstrated that As(V) was the dominant arsenic speciation adsorbed on iron (hydr)oxides. This study provides a promising alternative for remediation of arsenic contaminated soil in view of its low cost and environmental benign.

  11. Solar oxidation and removal of arsenic--Key parameters for continuous flow applications.

    Science.gov (United States)

    Gill, L W; O'Farrell, C

    2015-12-01

    Solar oxidation to remove arsenic from water has previously been investigated as a batch process. This research has investigated the kinetic parameters for the design of a continuous flow solar reactor to remove arsenic from contaminated groundwater supplies. Continuous flow recirculated batch experiments were carried out under artificial UV light to investigate the effect of different parameters on arsenic removal efficiency. Inlet water arsenic concentrations of up to 1000 μg/L were reduced to below 10 μg/L requiring 12 mg/L iron after receiving 12 kJUV/L radiation. Citrate however was somewhat surprisingly found to promote a detrimental effect on the removal process in the continuous flow reactor studies which is contrary to results found in batch scale tests. The impact of other typical water groundwater quality parameters (phosphate and silica) on the process due to their competition with arsenic for photooxidation products revealed a much higher sensitivity to phosphate ions compared to silicate. Other results showed no benefit from the addition of TiO2 photocatalyst but enhanced arsenic removal at higher temperatures up to 40 °C. Overall, these results have indicated the kinetic envelope from which a continuous flow SORAS single pass system could be more confidently designed for a full-scale community groundwater application at a village level.

  12. A novel role of hematopoietic CCL5 in promoting triple-negative mammary tumor progression by regulating generation of myeloid-derived suppressor cells

    Institute of Scientific and Technical Information of China (English)

    Yan Zhang; Dandan Lv; Ha-Jeong Kim; Robert A Kurt; Wen Bu; Yi Li; Xiaojing Ma

    2013-01-01

    CCL5 is a member of the CC chemokine family expressed in a wide array of immune and non-immune cells in response to stress signals.CCL5 expression correlates with advanced human breast cancer.However,its functional significance and mode of action have not been established.Here,we show that CCL5-deficient mice are resistant to highly aggressive,triple-negative mammary tumor growth.Hematopoietic CCL5 is dominant in this phenotype.The absence of hematopoietic CCL5 causes aberrant generation of CD11b+/Gr-1+,myeloid-derived suppressor cells (MDSCs) in the bone marrow in response to tumor growth by accumulating Ly6Chi and Ly6G+ MDSCs with impaired capacity to suppress cytotoxicity of CD8+ T cells.These properties of CCL5 are observed in both orthotopic and spontaneous mammary tumors.Antibody-mediated systemic blockade of CCL5 inhibits tumor progression and enhances the efficacy of therapeutic vaccination against non-immunogenic tumors.CCL5 also helps maintain the immunosuppressive capacity of human MDSCs.Our study uncovers a novel,chemokine-independent activity of the hematopoietically derived CCL5 that promotes mammary tumor progression via generating MDSCs in the bone marrow in cooperation with tumor-derived colony-stimulating factors.The study sheds considerable light on the interplay between the hematopoietic compartment and tumor niche.Because of the apparent dispensable nature of this molecule in normal physiology,CCL5 may represent an excellent therapeutic target in immunotherapy for breast cancer as well as a broad range of solid tumors that have significant amounts of MDSC infiltration.

  13. Speciation analysis of arsenic in groundwater from Inner Mongolia with an emphasis on acid-leachable particulate arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Gong Zhilong [Department of Public Health Sciences, University of Alberta, 10-102 Clinical Sciences Building, Edmonton, Alta., T6G 2G3 (Canada); Lu Xiufen [Department of Public Health Sciences, University of Alberta, 10-102 Clinical Sciences Building, Edmonton, Alta., T6G 2G3 (Canada); Watt, Corinna [Department of Public Health Sciences, University of Alberta, 10-102 Clinical Sciences Building, Edmonton, Alta., T6G 2G3 (Canada); Wen Bei [Department of Public Health Sciences, University of Alberta, 10-102 Clinical Sciences Building, Edmonton, Alta., T6G 2G3 (Canada); He Bin [Department of Public Health Sciences, University of Alberta, 10-102 Clinical Sciences Building, Edmonton, Alta., T6G 2G3 (Canada); Mumford, Judy [National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Human Studies Division, Epidemiology and Biomarkers Branch, Research Triangle Park, NC 27711 (United States); Ning Zhixiong [Ba Men Anti-Epidemic Station, Lin He, Inner Mongolia (China); Xia Yajuan [Inner Mongolia Center for Endemic Disease Control and Research, Huhhot, Inner Mongolia (China); Le, X. Chris [Department of Public Health Sciences, University of Alberta, 10-102 Clinical Sciences Building, Edmonton, Alta., T6G 2G3 (Canada)]. E-mail: xc.le@ualberta.ca

    2006-01-05

    Arsenic in drinking water affects millions of people around the world. While soluble arsenic is commonly measured, the amount of particulate arsenic in drinking water has often been overlooked. We report here determination of the acid-leachable particulate arsenic and soluble arsenicals in well water from an arsenic-poisoning endemic area in Inner Mongolia, China. Water samples (583) were collected from 120 wells in Ba Men, Inner Mongolia, where well water was the primary drinking water source. Two methods were demonstrated for the determination of soluble arsenic species (primarily inorganic arsenate and arsenite) and total particulate arsenic. The first method used solid phase extraction cartridges and membrane filters to separate arsenic species on-site, followed by analysis of the individual arsenic species eluted from the cartridges and filters. The other method uses liquid chromatography separation with hydride generation atomic fluorescence detection to determine soluble arsenic species. Analysis of acidified water samples using inductively coupled plasma mass spectrometry provided the total arsenic concentration. Arsenic concentrations in water samples from the 120 wells ranged from <1 to {approx}1000 {mu}g L{sup -1}. On average, particulate arsenic accounted for 39 {+-} 38% (median 36%) of the total arsenic. In some wells, particulate arsenic was six times higher than the soluble arsenic concentration. Particulate arsenic can be effectively removed using membrane filtration. The information on particulate and soluble arsenic in water is useful for optimizing treatment options and for understanding the geochemical behavior of arsenic in groundwater.

  14. Expression of a phosphorylated substrate domain of p130Cas promotes PyMT-induced c-Src-dependent murine breast cancer progression.

    Science.gov (United States)

    Zhao, Yingshe; Kumbrink, Joerg; Lin, Bor-Tyh; Bouton, Amy H; Yang, Shi; Toselli, Paul A; Kirsch, Kathrin H

    2013-12-01

    Elevated expression of p130Cas (Crk-associated substrate)/BCAR1 (breast cancer antiestrogen resistance 1) in human breast tumors is a marker of poor prognosis and poor overall survival. p130Cas is a downstream target of the tyrosine kinase c-Src. Signaling mediated by p130Cas through its phosphorylated substrate domain (SD) and interaction with effector molecules directly promotes tumor progression. We previously developed a constitutively phosphorylated p130Cas SD molecule, Src*/SD (formerly referred to as Src*/CasSD), which acts as decoy molecule and attenuates the transformed phenotype in v-crk-transformed murine fibroblasts and human breast cancer cells. To test the function of this molecule in vivo, we established mouse mammary tumor virus (MMTV)-long terminal repeat-Src*/SD transgenic mice in which mammary gland development and tumor formation were analyzed. Transgenic expression of the Src*/SD molecule under the MMTV-long terminal repeat promoter did not interfere with normal mammary gland development or induce tumors in mice observed for up to 11 months. To evaluate the effects of the Src*/SD molecule on tumor development in vivo, we utilized the MMTV-polyoma middle T-antigen (PyMT) murine breast cancer model that depends on c-Src. PyMT mice crossed with Src*/SD mice displayed accelerated tumor formation. The earlier onset of tumors can be explained by the interaction of the Src* domain with PyMT and targeting the fused phosphorylated SD to the membrane. At membrane compartments, it might integrate membrane-associated active signaling complexes leading to increased proliferation measured by phospho-Histone H3 staining. Although these results were unexpected, they emphasize the importance of preventing the membrane association of Src*/SD when employed as decoy molecule.

  15. Demand-based water options for arsenic mitigation: an experience from rural Bangladesh.

    Science.gov (United States)

    Hoque, B A; Hoque, M M; Ahmed, T; Islam, S; Azad, A K; Ali, N; Hossain, M; Hossain, M S

    2004-01-01

    A supply of safe drinking water is a recognized global concern. The arsenic contamination of groundwater in Bangladesh and other countries has furthered this concern. Lack of appropriate water options is one of the main barriers to the supply of safe drinking water for 30-60 million people who are exposed to the risk of drinking arsenic-contaminated water in Bangladesh. This paper describes the experience from a water supply programme for arsenic mitigation based on demand and participation of 30,000 rural people in Srinagar, a subdistrict of Bangladesh. About 85% of the 912 tubewell water samples tested had an arsenic content higher than 0.05 mg/l. The project promoted 11 options including groundwater, surface-water and rainwater-harvesting household-based options as well as community managed technologies. Most people, particularly women, wanted piped water, and hand-operated deep tubewells were also requested. Four cluster-based motorized piped water systems, 20 home-based arsenic-removal options (two types) and an arsenic-removal filter plant were installed. The public contributed about 49, 25 and 20% of the installation costs of piped water, home-based options and filter options, respectively, and 100% of all operation and maintenance costs. The household options and filter plant were abandoned within a few weeks. Reportedly, those options required too much attention, discharged small volumes of water at low rates, were difficult to maintain, and discharged poor-quality water. The proportion of families (54%) that drank arsenic-contaminated water during the final survey was significantly lower than in the baseline survey (87%). For arsenic-affected areas, it is recommended that a cluster-based piped water system be given proper consideration when selecting appropriate water options rather than household-based options or the development of new low-cost options.

  16. Simultaneous detection of bioavailable arsenic and cadmium in contaminated soils using dual-sensing bioreporters.

    Science.gov (United States)

    Yoon, Youngdae; Kim, Sunghoon; Chae, Yooeun; Kim, Shin Woong; Kang, Yerin; An, Gyeonghyeon; Jeong, Seung-Woo; An, Youn-Joo

    2016-04-01

    Whole-cell bioreporters (WCBs) have attracted increasing attention during the last few decades because they allow fast determination of bioavailable heavy metals in contaminated sites. Various WCBs to monitor specific heavy metals such as arsenic and cadmium in diverse environmental systems are available. However, currently, no study on simultaneous analysis of arsenic and cadmium has been reported, even though soils are contaminated by diverse heavy metals and metalloids. We demonstrated herein the development of dual-sensing WCBs to simultaneously quantify bioavailable arsenic and cadmium in contaminated sites by employing the promoter regions of the ars and znt operons as separate metal-sensing domains, and egfp and mcherry as reporter genes. The dual-sensing WCBs were generated by inserting two sets of genes into E. coli DH5α. The capability of WCBs was successfully proved to simultaneously quantify bioavailable arsenic and cadmium in amended Landwirtschaftliche Untersuchungs und Forschungsanstalt (LUFA) soils, and then, it was applied to contaminated field soils collected from a smelter area in Korea. As a result, it was noticed that the bioavailable portion of cadmium was higher than that of arsenic while the absolute amount of bioavailable arsenic and cadmium level was opposite. Since both cadmium and arsenic were assessed from the same E. coli cells, the data obtained by using dual-sensing WCBs would be more efficient and convenient than that from comparative WCB assay. In spite of advantageous aspects, to our knowledge, this is the first report on a dual-sensing WCB for rapid and concurrent quantification of bioavailable arsenic and cadmium in contaminated soils.

  17. Possible mechanisms for arsenic-induced proliferative diseases

    Energy Technology Data Exchange (ETDEWEB)

    Wetterhahn, K.E.; Dudek, E.J.; Shumilla, J.A. [Dartmouth College and Medical School, Hanover, NH (United States)] [and others

    1996-12-31

    Possible mechanisms for cardiovascular diseases and cancers which have been observed on chronic exposure to arsenic have been investigated. We tested the hypothesis that nonlethal levels of arsenic are mitogenic, cause oxidative stress, increase nuclear translocation of trans-acting factors, and increase expression of genes involved in proliferation. Cultured porcine vascular (from aorta) endothelial cells were used as a model cell system to study the effects of arsenic on the target cells for cardiovascular diseases. Treatment of postconfluent cell cultures with nonovertly toxic concentrations of arsenite increased DNA synthesis, similar to the mitogenic response observed with hydrogen peroxide. Within 1 hour of adding noncytotoxic concentrations of arsenite, cellular levels of oxidants increased relative to control levels, indicating that arsenite promotes cellular oxidations. Arsenite treatment increased nuclear translocation of NF-{kappa}B, an oxidative stress-responsive transcription factor, in a manner similar to that observed with hydrogen peroxide. Pretreatment of intact cells with the antioxidants N-acetylcysteine and dimethylfumarate prevented the arsenite-induced increases in cellular oxidant formation and NF-KB translocation. Arsenite had little or no effect on binding of NF-KB to its DNA recognition sequence in vitro, indicating that it is unlikely that arsenite directly affects NF-KB. The steady-state mRNA levels of intracellular adhesion molecule and urokinase-like plasminogen activator, genes associated with the active endothelial phenotype in arteriosclerosis and cancer metastasis, were increased by nontoxic concentrations of arsenite. These data suggest that arsenite promotes proliferative diseases like heart disease and cancer by activating oxidant-sensitive endothelial cell signaling and gene expression. It is possible that antioxidant therapy would be useful in preventing arsenic-induced cardiovascular disease and cancer.

  18. Selective hyaluronan-CD44 signaling promotes miRNA-21 expression and interacts with vitamin D function during cutaneous squamous cell carcinomas progression following UV irradiation

    Directory of Open Access Journals (Sweden)

    Lilly YW Bourguignon

    2015-05-01

    Full Text Available Hyaluronan (HA, the major extracellular matrix component, is often anchored to CD44 isoforms, a family of structurally/functionally important cell surface receptors. Our recent results indicate that UV irradiation (UVR-induced cutaneous squamous cell carcinomas (SCC overexpress a variety of CD44 variant isoforms (CD44v, with different CD44v isoforms appear to confer malignant SCC properties. UVR also stimulates HA degradation in epidermal keratinocytes. Both large HA polymers and their UVR-induced catabolic products (small HA selectively activate CD44 isoform-mediated cellular signaling in normal keratinocytes and SCC cells, with all of the downstream processes being mediated by RhoGTPases (e.g., RhoA and Rac1. Importantly, we found that the hormonally active form of vitamin D (1,25(OH2D3 not only prevents the UVR-induced small HA activation of abnormal keratinocyte behavior and SCC progression, but also enhances large HA stimulation of normal keratinocyte activities and epidermal function(s. Furthermore, we found that HA and its UVR-induced catabolic products (e.g., large and small HA selectively activate CD44-mediated Rac and RhoA signaling. Specifically, large HA-CD44 interaction promotes Rac/PKNγ-dependent normal keratinocyte differentiation, DNA repair and keratinocyte survival. Conversely, small HA-CD44v isoform interaction stimulates RhoA/ROK-dependent NFκB signaling and microRNA-21 (miR-21 production, leading to inflammation, proliferation (following acute UVR response and SCC progression (following chronic UVR exposure. Active vitamin D inhibits small HA-CD44v-mediated RhoA/ROK signaling and SCC progression; and it also enhances large HA-CD44-mediated differentiation, DNA repair and normal epidermal function. Selective applications of large HA and vitamin D will be used to improve the UVR-induced HA (small vs. large HA-CD44 isoform interaction with RhoGTPase signaling and skin inflammation as a potential therapeutic treatment for skin

  19. Urinary Arsenic Metabolites of Subjects Exposed to Elevated Arsenic Present in Coal in Shaanxi Province, China

    Directory of Open Access Journals (Sweden)

    Linsheng Yang

    2011-06-01

    Full Text Available In contrast to arsenic (As poisoning caused by naturally occurring inorganic arsenic-contaminated water consumption, coal arsenic poisoning (CAP induced by elevated arsenic exposure from coal combustion has rarely been reported. In this study, the concentrations and distributions of urinary arsenic metabolites in 57 volunteers (36 subjects with skin lesions and 21 subjects without skin lesions, who had been exposed to elevated levels of arsenic present in coal in Changshapu village in the south of Shaanxi Province (China, were reported. The urinary arsenic species, including inorganic arsenic (iAs [arsenite (iAsIII and arsenate (iAsV], monomethylarsonic acid (MMAV and dimethylarsinic acid (DMAV, were determined by high-performance liquid chromatography (HPLC combined with inductively coupled plasma mass spectroscopy (ICP-MS. The relative distributions of arsenic species, the primary methylation index (PMI = MMAV/iAs and the secondary methylation index (SMI = DMAV/MMAV were calculated to assess the metabolism of arsenic. Subjects with skin lesions had a higher concentration of urinary arsenic and a lower arsenic methylation capability than subjects without skin lesions. Women had a significantly higher methylation capability of arsenic than men, as defined by a higher percent DMAV and SMI in urine among women, which was the one possible interpretation of women with a higher concentration of urinary arsenic but lower susceptibility to skin lesions. The findings suggested that not only the dose of arsenic exposure but also the arsenic methylation capability have an impact on the individual susceptibility to skin lesions induced by coal arsenic exposure.

  20. Chronic arsenic poisoning from burning high-arsenic-containing coal in Guizhou, China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J.; Zheng, B.S.; Aposhian, H.V.; Zhou, Y.S.; Chen, M.L.; Zhang, A.H.; Waalkes, M.P. [NIEHS, Research Triangle Park, NC (USA)

    2002-07-01

    Arsenic is an environmental hazard and the reduction of drinking water arsenic levels is under consideration. People are exposed to arsenic not only through drinking water but also through arsenic-contaminated air and food. Here the health effects of arsenic exposure from burning high arsenic-containing coal in Guizhou, China was investigated. Coal is burned inside the home in open pits for daily cooking and crop drying, producing a high concentration of arsenic in indoor air. Arsenic in the air coats and permeates food being dried producing high concentrations in food; however, arsenic concentrations in the drinking water are in the normal range. The estimated sources of total arsenic exposure in this area are from arsenic-contaminated food (50-80%), air (10-20%), water (1-5%), and direct contact in coal-mining workers (1%). At least 3,000 patients with arsenic poisoning were found in the Southwest Prefecture of Guizhou, and approximately 200,000 people are at risk for such over exposures. Skin lesions are common, including keratosis of the hands and feet, pigmentation on the trunk, skin ulceration, and skin cancers. Toxicities to internal organs, including lung dysfunction, neuropathy, and nephrotoxicity, are clinically evident. The prevalence of hepatomegaly was 20%, and cirrhosis, ascites, and liver cancer are the most serious outcomes of arsenic poisoning. The Chinese government and international organizations are attempting to improve the house conditions and the coal source, and thereby protect human health in this area.

  1. Activity of the AtMRP3 promoter in transgenic Arabidopsis thaliana and Nicotiana tabacum plants is increased by cadmium, nickel, arsenic, cobalt and lead but not by zinc and iron

    NARCIS (Netherlands)

    Zientara, K.; Wawrzynska, A.; Lukomska, J.; Lopez Moya, J.R.; Liszewska, F.; Assuncao, A.G.L.; Aarts, M.G.M.; Sirko, A.

    2009-01-01

    Characterization of the function, regulation and metal-specificity of metal transporters is one of the basic steps needed for the understanding of transport and accumulation of toxic metals and metalloids by plants. In this work GUS was used as a reporter for monitoring the activity of the promoter

  2. 蜈蚣草砷超富集机制及其在砷污染修复中的应用%Advance of the Mechanisms of Arsenic Hyperaccumulation in Pteris vittata L. and Applications for Arsenic-Remediation

    Institute of Scientific and Technical Information of China (English)

    申红玲; 何振艳; 麻密

    2014-01-01

    The fern Pteris vittata can absorb arsenic from the soil, and most of arsenic is transported to the abo-veground tissues, stored in the vacuole of fronds. P. vittata has an efifcient antioxidant system which can reduce arsenic poisoning. Importantly, the arsenate reduction system and vacuole sequestration are critical for arsenic detoxiifcation and arsenic hyperaccumulation. In this review, the latest research progress about the physiologi-cal and molecular mechanisms of arsenic tolerance and accumulation in P. vittata was summarized, and the fu-ture applications of this fern for remediation of removal arsenic-contaminated soils or water were discussed as well.%蕨类植物蜈蚣草能够从土壤中吸收砷,并储存于地上部分羽叶的液泡中。蜈蚣草具有高效的抗氧化系统,以降低砷的毒害;其砷酸还原系统和液泡区隔化是蜈蚣草进行砷解毒和砷超富集的重要机制。本文综述了目前蜈蚣草砷超富集机制研究的主要进展,并对其在修复砷污染环境的应用中进行了讨论。

  3. Methanogenic inhibition by arsenic compounds.

    Science.gov (United States)

    Sierra-Alvarez, Reyes; Cortinas, Irail; Yenal, Umur; Field, Jim A

    2004-09-01

    The acute acetoclastic methanogenic inhibition of several inorganic and organic arsenicals was assayed. Trivalent species, i.e., methylarsonous acid and arsenite, were highly inhibitory, with 50% inhibitory concentrations of 9.1 and 15.0 microM, respectively, whereas pentavalent species were generally nontoxic. The nitrophenylarsonate derivate, roxarsone, displayed moderate toxicity.

  4. Acute arsenic poisoning diagnosed late.

    Science.gov (United States)

    Shumy, Farzana; Anam, Ahmad Mursel; Kamruzzaman, A K M; Amin, Md Robed; Chowdhury, M A Jalil

    2016-04-01

    Acute arsenicosis, although having a 'historical' background, is not common in our times. This report describes a case of acute arsenic poisoning, missed initially due to its gastroenteritis-like presentation, but suspected and confirmed much later, when the patient sought medical help for delayed complications after about 2 months.

  5. The microbial genomics of arsenic.

    Science.gov (United States)

    Andres, Jérémy; Bertin, Philippe N

    2016-03-01

    Arsenic, which is a major contaminant of many aquatic ecosystems worldwide, is responsible for serious public health issues. However, life has evolved various strategies for coping with this toxic element. In particular, prokaryotic organisms have developed processes enabling them to resist and metabolize this chemical. Studies based on genome sequencing and transcriptome, proteome and metabolome profiling have greatly improved our knowledge of prokaryotes' metabolic potential and functioning in contaminated environments. The increasing number of genomes available and the development of descriptive and comparative approaches have made it possible not only to identify several genetic determinants of the arsenic metabolism, but also to elucidate their phylogenetic distribution and their modes of regulation. In addition, studies using functional genomic tools have established the pleiotropic character of prokaryotes' responses to arsenic, which can be either common to several species or species-specific. These approaches also provide promising means of deciphering the functioning of microbial communities including uncultured organisms, the genetic transfers involved and the possible occurrence of metabolic interactions as well as the evolution of arsenic resistance and metabolism.

  6. Cellular arsenic transport pathways in mammals.

    Science.gov (United States)

    Roggenbeck, Barbara A; Banerjee, Mayukh; Leslie, Elaine M

    2016-11-01

    Natural contamination of drinking water with arsenic results in the exposure of millions of people world-wide to unacceptable levels of this metalloid. This is a serious global health problem because arsenic is a Group 1 (proven) human carcinogen and chronic exposure is known to cause skin, lung, and bladder tumors. Furthermore, arsenic exposure can result in a myriad of other adverse health effects including diseases of the cardiovascular, respiratory, neurological, reproductive, and endocrine systems. In addition to chronic environmental exposure to arsenic, arsenic trioxide is approved for the clinical treatment of acute promyelocytic leukemia, and is in clinical trials for other hematological malignancies as well as solid tumors. Considerable inter-individual variability in susceptibility to arsenic-induced disease and toxicity exists, and the reasons for such differences are incompletely understood. Transport pathways that influence the cellular uptake and export of arsenic contribute to regulating its cellular, tissue, and ultimately body levels. In the current review, membrane proteins (including phosphate transporters, aquaglyceroporin channels, solute carrier proteins, and ATP-binding cassette transporters) shown experimentally to contribute to the passage of inorganic, methylated, and/or glutathionylated arsenic species across cellular membranes are discussed. Furthermore, what is known about arsenic transporters in organs involved in absorption, distribution, and metabolism and how transport pathways contribute to arsenic elimination are described.

  7. Poisoning of bees by industrial arsenic emissions

    Energy Technology Data Exchange (ETDEWEB)

    Jaroslav, S.

    1962-01-01

    Massive poisoning of bees by industrial arsenic emissions in Czechoslovakia are reviewed. Arsenic emissions from an ore processing plant in Tesin were responsible for massive bee deaths after World War I. Massive death of bees was observed in 1938 in the Krompach region around a copper ore smelting plant which emitted arsenic. Other accidents were reported in 1954 and 1957 in areas around industrial plants and power plants using arsenopyrite-containing low-grade coal or lignite. Arsenic was emitted bound in fly-ash in the form of arsenic trioxide or, in the case of coals containing alkaline chlorides, in the form of arsenic trichloride. The arsenic contamination extended to areas within a radius of 3 to 7 km. Settled fly-ash contained 0.0004 to 0.75 percent arsenic, which was soluble in a citrate-hydrochloric acid solution of pH 3.9, which corresponds to the gastric acid of bees. The arsenic uptake by the bees from pollen was calculated to amount to 1 microgram daily, against a toxic dose of 0.37 microgram. The toxic effect of arsenic on bees can be abated by adding colloidal iron hydroxide to the sugar solution which they are fed.

  8. Poisoning of bees by industrial arsenic emissions

    Energy Technology Data Exchange (ETDEWEB)

    Svoboda, J.

    1962-01-01

    Massive poisoning of bees by industrial arsenic emissions in Czechoslovakia are reviewed. Arsenic emissions from an ore processing plant in Tesin were responsible for massive bee deaths after World War I. Massive death of bees was observed in 1938 in the Krompach region around a copper ore smelting plant which emitted arsenic. Other accidents were reported in 1954 and 1957 in areas around industrial plants and power plants using arsenopyrite-containing low-grade coal or lignite. Arsenic was emitted bound in fly-ash in the form of arsenic trioxide or, in the case of coals containing alkaline chlorides, in the form of arsenic trichloride. The arsenic contamination extended to areas within a radius of 3-7 km. Settled fly-ash contained 0.0004-0.75% arsenic, which was soluble in a citrate-hydrochloric acid solution of pH 3.9, which corresponds to the gastric acid of bees. The arsenic uptake by the bees from pollen was calculated to amount to 1 microgram daily, against a toxic dose of 0.37 microgram. The toxic effect of arsenic on bees can be abated by adding colloidal iron hydroxide to the sugar solution which they are fed. 5 references.

  9. Sequestration of arsenic in ombrotrophic peatlands

    Science.gov (United States)

    Rothwell, James; Hudson-Edwards, Karen; Taylor, Kevin; Polya, David; Evans, Martin; Allott, Tim

    2014-05-01

    Peatlands can be important stores of arsenic but we are lacking spectroscopic evidence of the sequestration pathways of this toxic metalloid in peatland environments. This study reports on the solid-phase speciation of anthropogenically-derived arsenic in atmospherically contaminated peat from the Peak District National Park (UK). Surface and sub-surface peat samples were analysed by synchrotron X-ray absorption spectroscopy on B18 beamline at Diamond Light Source (UK). The results suggest that there are contrasting arsenic sequestration mechanisms in the peat. The bulk arsenic speciation results, in combination with strong arsenic-iron correlations at the surface, suggest that iron (hydr)oxides are key phases for the immobilisation of arsenic at the peat surface. In contrast, the deeper peat samples are dominated by arsenic sulphides (arsenopyrite, realgar and orpiment). Given that these peats receive inputs solely from the atmosphere, the presence of these sulphide phases suggests an in-situ authigenic formation. Redox oscillations in the peat due to a fluctuating water table and an abundant store of legacy sulphur from historic acid rain inputs may favour the precipitation of arsenic sequestering sulphides in sub-surface horizons. Oxidation-induced loss of these arsenic sequestering sulphur species by water table drawdown has important implications for the mobility of arsenic and the quality of waters draining peatlands.

  10. Arsenic chemistry in soils and sediments

    Energy Technology Data Exchange (ETDEWEB)

    Fendorf, S.; Nico, P.; Kocar, B.D.; Masue, Y.; Tufano, K.J.

    2009-10-15

    Arsenic is a naturally occurring trace element that poses a threat to human and ecosystem health, particularly when incorporated into food or water supplies. The greatest risk imposed by arsenic to human health results from contamination of drinking water, for which the World Health Organization recommends a maximum limit of 10 {micro}g L{sup -1}. Continued ingestion of drinking water having hazardous levels of arsenic can lead to arsenicosis and cancers of the bladder, skin, lungs and kidneys. Unfortunately, arsenic tainted drinking waters are a global threat and presently having a devastating impact on human health within Asia. Nearly 100 million people, for example, are presently consuming drinking water having arsenic concentrations exceeding the World Health Organization's recommended limit (Ahmed et al., 2006). Arsenic contamination of the environment often results from human activities such as mining or pesticide application, but recently natural sources of arsenic have demonstrated a devastating impact on water quality. Arsenic becomes problematic from a health perspective principally when it partitions into the aqueous rather than the solid phase. Dissolved concentrations, and the resulting mobility, of arsenic within soils and sediments are the combined result of biogeochemical processes linked to hydrologic factors. Processes favoring the partitioning of As into the aqueous phase, potentially leading to hazardous concentrations, vary extensively but can broadly be grouped into four categories: (1) ion displacement, (2) desorption (or limited sorption) at pH values > 8.5, (3) reduction of arsenate to arsenite, and (4) mineral dissolution, particularly reductive dissolution of Fe and Mn (hydr)oxides. Although various processes may liberate arsenic from solids, a transition from aerobic to anaerobic conditions, and commensurate arsenic and iron/manganese reduction, appears to be a dominant, but not exclusive, means by which high concentrations of

  11. The effect of variable environmental arsenic contamination on urinary concentrations of arsenic species.

    OpenAIRE

    Kalman, D A; Hughes, J; BELLE, G.; Burbacher, T; Bolgiano, D; Coble, K; Mottet, N. K.; Polissar, L

    1990-01-01

    Urinary arsenic species have been determined for approximately 3000 urine samples obtained from residents of a community surrounding an arsenic-emitting copper smelter. Levels of inorganic, monomethylated and dimethylated arsenic species ranged from less than 1 microgram/L (the instrumental detection limit) to 180 micrograms/L seen for dimethyl arsenic. Comparison of a subsample of this population that had the least environmental contamination with the subsample having highest environmental a...

  12. Arsenic adsorption of lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil

    OpenAIRE

    Wuthiphun, L.; Towatana, P.; Arrykul, S.; Chongsuvivatwong, V

    2007-01-01

    Arsenic adsorption efficiency of soil covering materials (lateritic soil, limestone powder, lime and fly ash) on arsenic-contaminated soil obtained from Ronpiboon District, Nakhon Sri Thammarat Province tosolve arsenic air pollution problem was investigated using batch experiments. The four types of the aforementioned soil covering materials were examined to determine their arsenic adsorption efficiency, equilibriumtime as well as adsorption isotherms.The results revealed that among soil cove...

  13. Outbreak of arsenic and toxaphene poisoning in Kenyan cattle. [Arsenic was detected in cattle dips

    Energy Technology Data Exchange (ETDEWEB)

    Maitai, C.K.; Kamau, J.A.; Gacuhi, D.M.; Njoroge, S.

    1975-02-15

    In a case of poisoning involving 70 cattle analysis of specimens obtained during post mortem examination showed that the toxic substances were arsenic and toxaphene. This was consistent with both the clinical and post mortem findings. Arsenic was detected in water from an abandoned cattle dip in the farm. Soil samples collected in the vicinity of the dip contained both arsenic and toxaphene.

  14. Method of arsenic removal from water

    Energy Technology Data Exchange (ETDEWEB)

    Gadgil, Ashok (El Cerrito, CA)

    2010-10-26

    A method for low-cost arsenic removal from drinking water using chemically prepared bottom ash pre-treated with ferrous sulfate and then sodium hydroxide. Deposits on the surface of particles of bottom ash form of activated iron adsorbent with a high affinity for arsenic. In laboratory tests, a miniscule 5 grams of pre-treated bottom ash was sufficient to remove the arsenic from 2 liters of 2400 ppb (parts per billion) arsenic-laden water to a level below 50 ppb (the present United States Environmental Protection Agency limit). By increasing the amount of pre-treated bottom ash, even lower levels of post-treatment arsenic are expected. It is further expected that this invention supplies a very low-cost solution to arsenic poisoning for large population segments.

  15. Slow recovery from severe inorganic arsenic poisoning despite treatment with DMSA (2.3-dimercaptosuccinic acid).

    Science.gov (United States)

    Stenehjem, Aud-E; Vahter, Marie; Nermell, Barbro; Aasen, Jorulf; Lierhagen, Syverin; Mørland, Jørg; Jacobsen, Dag

    2007-05-01

    A 39-year-old woman was hospitalized for nausea, diarrhea, vomiting, and weakness of unknown etiology. Her condition progressively deteriorated and she developed multiple organ failure and tetraplegia. The diagnosis of inorganic arsenic poisoning was established by measurements of arsenic in urine and serum, showing 2,000 microg/L (normal treatment probably had no significant effect on the total body clearance in our patient. The source of the poisoning was never detected, nor the motivation behind it. Criminal intent was suspected, but no verdict was given.

  16. Arsenic geochemistry of groundwater in Southeast Asia.

    Science.gov (United States)

    Kim, Kyoung-Woong; Chanpiwat, Penradee; Hanh, Hoang Thi; Phan, Kongkea; Sthiannopkao, Suthipong

    2011-12-01

    The occurrence of high concentrations of arsenic in the groundwater of the Southeast Asia region has received much attention in the past decade. This study presents an overview of the arsenic contamination problems in Vietnam, Cambodia, Lao People's Democratic Republic and Thailand. Most groundwater used as a source of drinking water in rural areas has been found to be contaminated with arsenic exceeding the WHO drinking water guideline of 10 μg·L(-1). With the exception of Thailand, groundwater was found to be contaminated with naturally occurring arsenic in the region. Interestingly, high arsenic concentrations (> 10 μg·L(-1)) were generally found in the floodplain areas located along the Mekong River. The source of elevated arsenic concentrations in groundwater is thought to be the release of arsenic from river sediments under highly reducing conditions. In Thailand, arsenic has never been found naturally in groundwater, but originates from tin mining activities. More than 10 million residents in Southeast Asia are estimated to be at risk from consuming arsenic-contaminated groundwater. In Southeast Asia, groundwater has been found to be a significant source of daily inorganic arsenic intake in humans. A positive correlation between groundwater arsenic concentration and arsenic concentration in human hair has been observed in Cambodia and Vietnam. A substantial knowledge gap exists between the epidemiology of arsenicosis and its impact on human health. More collaborative studies particularly on the scope of public health and its epidemiology are needed to conduct to fulfill the knowledge gaps of As as well as to enhance the operational responses to As issue in Southeast Asian countries.

  17. Arsenic stress after the Proterozoic glaciations

    OpenAIRE

    Chi Fru, Ernest; Arvestål, Emma; Callac, Nolwenn; El Albani, Abderrazak; Kilias, Stephanos; Argyraki, Ariadne; Jakobsson, Martin

    2015-01-01

    Protection against arsenic damage in organisms positioned deep in the tree of life points to early evolutionary sensitization. Here, marine sedimentary records reveal a Proterozoic arsenic concentration patterned to glacial-interglacial ages. The low glacial and high interglacial sedimentary arsenic concentrations, suggest deteriorating habitable marine conditions may have coincided with atmospheric oxygen decline after ~2.1 billion years ago. A similar intensification of near continental mar...

  18. Presence of Arsenic in Commercial Beverages

    Directory of Open Access Journals (Sweden)

    Jason Roberge

    2009-01-01

    Full Text Available Problem statement: This study’s goal was to assess the arsenic concentration of various beverages and broths purchased from a local chain supermarket. A source of chronic arsenic exposure occurs via food and beverage consumption. Groundwater levels of total arsenic are regulated (-1 by the Environmental Protection Agency (EPA but few studies have examined arsenic concentrations in common beverages. Approach: In the initial analysis of 19 items, total arsenic concentration was assessed from a variety of fruit juices, sports drinks, sodas and broths. Items found to contain levels of total arsenic ≥5.0 µg L-1 were further evaluated. Additional analysis included purchasing multiple brands of items ≥5.0 µg L-1and analyzing them for total arsenic and chemical species of arsenic. Results: Among the beverages in the initial analysis, apple juice (10.79 µg L-1 and grape juice (49.87 µg L-1 contained the highest levels of total arsenic. Upon examination of items with As concentrations above 5.0 µg L-1, varying concentrations of total arsenic were found in apple cider (range: 5.41-15.27 µg L-1, apple juice (range: 10.67-22.35 µg L-1, baby fruit juice (range: 13.91-16.51 µg L-1 and grape juice (range: 17.69-47.59 µg L-1. Conclusion: Many commercially available juices contained concentrations of arsenic that were higher than the standard for total arsenic allowed in groundwater as set forth by the EPA. The concentration of As in these juices varied between and within brands. In general, those consuming apple and grape juices are the young and elderly and it is these populations that may be more vulnerable to over exposure of heavy metals.

  19. Arsenic and antimony transporters in eukaryotes.

    Science.gov (United States)

    Maciaszczyk-Dziubinska, Ewa; Wawrzycka, Donata; Wysocki, Robert

    2012-01-01

    Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or glutathione followed by sequestration into the vacuole. Understanding of arsenic and antimony transport system is of high importance due to the increasing usage of arsenic-based drugs in the treatment of certain types of cancer and diseases caused by protozoan parasites as well as for the development of bio- and phytoremediation strategies for metalloid polluted areas. However, in contrast to prokaryotes, the knowledge about specific transporters of arsenic and antimony and the mechanisms of metalloid transport in eukaryotes has been very limited for a long time. Here, we review the recent advances in understanding of arsenic and antimony transport pathways in eukaryotes, including a dual role of aquaglyceroporins in uptake and efflux of metalloids, elucidation of arsenic transport mechanism by the yeast Acr3 transporter and its role in arsenic hyperaccumulation in ferns, identification of vacuolar transporters of arsenic-phytochelatin complexes in plants and forms of arsenic substrates recognized by mammalian ABC transporters.

  20. In-tank recirculating arsenic treatment system

    Science.gov (United States)

    Brady, Patrick V.; Dwyer, Brian P.; Krumhansl, James L.; Chwirka, Joseph D.

    2009-04-07

    A low-cost, water treatment system and method for reducing arsenic contamination in small community water storage tanks. Arsenic is removed by using a submersible pump, sitting at the bottom of the tank, which continuously recirculates (at a low flow rate) arsenic-contaminated water through an attached and enclosed filter bed containing arsenic-sorbing media. The pump and treatment column can be either placed inside the tank (In-Tank) by manually-lowering through an access hole, or attached to the outside of the tank (Out-of-Tank), for easy replacement of the sorption media.

  1. Certain cases of poisoning by arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Cristol, P.; Fourcade, J.; Ravoire, J.; Bezenech, C.

    1939-05-01

    Cases of acute and chronic poisoning by arsenic are reported. Diffuse pains, angor, edema of the limbs and genitals, complicated by heptic insufficiency and chronic bronchitis were determined in a subject having lived near an industrial plant processing arseniferous ores for several years. The plant emitted several hundred kg of finely dispersed arsenic oxide daily which settled on forage and vegetables. Symptoms of poisoning by arsenic were also detected in cattle in the same area. The installation of Cottrell type dust separators has helped to suppress the arsenic oxide emissions.

  2. Arsenic-bound excitons in diamond

    Science.gov (United States)

    Barjon, J.; Jomard, F.; Morata, S.

    2014-01-01

    A set of new excitonic recombinations is observed in arsenic-implanted diamond. It is composed of two groups of emissions at 5.355/5.361 eV and at 5.215/5.220/5.227 eV. They are respectively attributed to the no-phonon and transverse-optical phonon-assisted recombinations of excitons bound to neutral arsenic donors. From the Haynes rule, an ionization energy of 0.41 eV is deduced for arsenic in diamond, which shows that arsenic is a shallower donor than phosphorus (0.6 eV), in agreement with theory.

  3. Arsenic speciation and sorption in natural environments

    Science.gov (United States)

    Campbell, Kate M.; Nordstrom, D. Kirk

    2014-01-01

    Aqueous arsenic speciation, or the chemical forms in which arsenic exists in water, is a challenging, interesting, and complicated aspect of environmental arsenic geochemistry. Arsenic has the ability to form a wide range of chemical bonds with carbon, oxygen, hydrogen, and sulfur, resulting in a large variety of compounds that exhibit a host of chemical and biochemical properties. Besides the intriguing chemical diversity, arsenic also has the rare capacity to capture our imaginations in a way that few elements can duplicate: it invokes images of foul play that range from sinister to comedic (e.g., “inheritance powder” and arsenic-spiked elderberry wine). However, the emergence of serious large-scale human health problems from chronic arsenic exposure in drinking water has placed a high priority on understanding environmental arsenic mobility, toxicity, and bioavailability, and chemical speciation is key to these important questions. Ultimately, the purpose of arsenic speciation research is to predict future occurrences, mitigate contamination, and provide successful management of water resources.

  4. Urinary arsenic species, toenail arsenic, and arsenic intake estimates in a Michigan population with low levels of arsenic in drinking water.

    Science.gov (United States)

    Rivera-Núñez, Zorimar; Meliker, Jaymie R; Meeker, John D; Slotnick, Melissa J; Nriagu, Jerome O

    2012-01-01

    The large disparity between arsenic concentrations in drinking water and urine remains unexplained. This study aims to evaluate predictors of urinary arsenic in a population exposed to low concentrations (≤50 μg/l) of arsenic in drinking water. Urine and drinking water samples were collected from a subsample (n=343) of a population enrolled in a bladder cancer case-control study in southeastern Michigan. Total arsenic in water and arsenic species in urine were determined using ICP-MS: arsenobetaine (AsB), arsenite (As[III]), arsenate (As[V]), methylarsenic acid (MMA[V]), and dimethylarsenic acid (DMA[V]). The sum of As[III], As[V], MMA[V], and DMA[V] was denoted as SumAs. Dietary information was obtained through a self-reported food intake questionnaire. Log(10)-transformed drinking water arsenic concentration at home was a significant (Pwater were removed and further improved when analyses were applied to individuals who consumed amounts of home drinking water above the median volume (R(2)=0.40, Pwater was 0.42. Results show that arsenic exposure from drinking water consumption is an important determinant of urinary arsenic concentrations, even in a population exposed to relatively low levels of arsenic in drinking water, and suggest that seafood intake may influence urinary DMA[V] concentrations.

  5. Sox17 promotes cell cycle progression and inhibits TGF-beta/Smad3 signaling to initiate progenitor cell behavior in the respiratory epithelium.

    Directory of Open Access Journals (Sweden)

    Alexander W Lange

    Full Text Available The Sry-related high mobility group box transcription factor Sox17 is required for diverse developmental processes including endoderm formation, vascular development, and fetal hematopoietic stem cell maintenance. Expression of Sox17 in mature respiratory epithelial cells causes proliferation and lineage respecification, suggesting that Sox17 can alter adult lung progenitor cell fate. In this paper, we identify mechanisms by which Sox17 influences lung epithelial progenitor cell behavior and reprograms cell fate in the mature respiratory epithelium. Conditional expression of Sox17 in epithelial cells of the adult mouse lung demonstrated that cell cluster formation and respecification of alveolar progenitor cells toward proximal airway lineages were rapidly reversible processes. Prolonged expression of Sox17 caused the ectopic formation of bronchiolar-like structures with diverse respiratory epithelial cell characteristics in alveolar regions of lung. During initiation of progenitor cell behavior, Sox17 induced proliferation and increased the expression of the progenitor cell marker Sca-1 and genes involved in cell cycle progression. Notably, Sox17 enhanced cyclin D1 expression in vivo and activated cyclin D1 promoter activity in vitro. Sox17 decreased the expression of transforming growth factor-beta (TGF-beta-responsive cell cycle inhibitors in the adult mouse lung, including p15, p21, and p57, and inhibited TGF-beta1-mediated transcriptional responses in vitro. Further, Sox17 interacted with Smad3 and blocked Smad3 DNA binding and transcriptional activity. Together, these data show that a subset of mature respiratory epithelial cells retains remarkable phenotypic plasticity and that Sox17, a gene required for early endoderm formation, activates the cell cycle and reinitiates multipotent progenitor cell behavior in mature lung cells.

  6. Tumor Progression Locus 2 Promotes Induction of IFNλ, Interferon Stimulated Genes and Antigen-Specific CD8+ T Cell Responses and Protects against Influenza Virus.

    Directory of Open Access Journals (Sweden)

    Teneema Kuriakose

    2015-08-01

    Full Text Available Mitogen-activated protein kinase (MAP cascades are important in antiviral immunity through their regulation of interferon (IFN production as well as virus replication. Although the serine-threonine MAP kinase tumor progression locus 2 (Tpl2/MAP3K8 has been implicated as a key regulator of Type I (IFNα/β and Type II (IFNγ IFNs, remarkably little is known about how Tpl2 might contribute to host defense against viruses. Herein, we investigated the role of Tpl2 in antiviral immune responses against influenza virus. We demonstrate that Tpl2 is an integral component of multiple virus sensing pathways, differentially regulating the induction of IFNα/β and IFNλ in a cell-type specific manner. Although Tpl2 is important in the regulation of both IFNα/β and IFNλ, only IFNλ required Tpl2 for its induction during influenza virus infection both in vitro and in vivo. Further studies revealed an unanticipated function for Tpl2 in transducing Type I IFN signals and promoting expression of interferon-stimulated genes (ISGs. Importantly, Tpl2 signaling in nonhematopoietic cells is necessary to limit early virus replication. In addition to early innate alterations, impaired expansion of virus-specific CD8+ T cells accompanied delayed viral clearance in Tpl2-/- mice at late time points. Consistent with its critical role in facilitating both innate and adaptive antiviral responses, Tpl2 is required for restricting morbidity and mortality associated with influenza virus infection. Collectively, these findings establish an essential role for Tpl2 in antiviral host defense mechanisms.

  7. Subsurface iron and arsenic removal for shallow tube well drinking water supply in rural Bangladesh.

    Science.gov (United States)

    van Halem, D; Olivero, S; de Vet, W W J M; Verberk, J Q J C; Amy, G L; van Dijk, J C

    2010-11-01

    Subsurface iron and arsenic removal has the potential to be a cost-effective technology to provide safe drinking water in rural decentralized applications, using existing shallow tube wells. A community-scale test facility in Bangladesh was constructed for injection of aerated water (∼1 m(3)) into an anoxic aquifer with elevated iron (0.27 mmolL(-1)) and arsenic (0.27μmolL(-1)) concentrations. The injection (oxidation) and abstraction (adsorption) cycles were monitored at the test facility and simultaneously simulated in the laboratory with anoxic column experiments. Dimensionless retardation factors (R) were determined to represent the delayed arrival of iron or arsenic in the well compared to the original groundwater. At the test facility the iron removal efficacies increased after every injection-abstraction cycle, with retardation factors (R(Fe)) up to 17. These high removal efficacies could not be explained by the theory of adsorptive-catalytic oxidation, and therefore other ((a)biotic or transport) processes have contributed to the system's efficacy. This finding was confirmed in the anoxic column experiments, since the mechanism of adsorptive-catalytic oxidation dominated in the columns and iron removal efficacies did not increase with every cycle (stable at R(Fe)=∼8). R(As) did not increase after multiple cycles, it remained stable around 2, illustrating that the process which is responsible for the effective iron removal did not promote the co-removal of arsenic. The columns showed that subsurface arsenic removal was an adsorptive process and only the freshly oxidized adsorbed iron was available for the co-adsorption of arsenic. This indicates that arsenic adsorption during subsurface treatment is controlled by the amount of adsorbed iron that is oxidized, and not by the amount of removed iron. For operational purposes this is an important finding, since apparently the oxygen concentration of the injection water does not control the subsurface arsenic

  8. Lead isotopic compositions of common arsenical pesticides used in New England

    Science.gov (United States)

    Ayuso, Robert; Foley, Nora; Robinson, Gilpin; Wandless, Gregory; Dillingham, Jeremy

    2004-01-01

    The three most important arsenical pesticides and herbicides that were extensively used on apple, blueberry, and potato crops in New England from mid-1800s to recent times are lead arsenate, calcium arsenate, and sodium arsenate. Lead arsenate was probably the most heavily used of the arsenical pesticides until it was banned in 1988. Other metal-arsenic pesticides were also used but in lesser amounts. A recent report identified areas in New England where arsenical pesticides were used extensively (Robinson and Ayuso, 2004). On the basis of factor analysis of metal concentrations in stream sediment samples, a positive correlation with pesticide use was shown in regions having stream sediment sample populations that contained concentrations of high arsenic and lead. Lead isotope compositions of stream sediments from areas with heavy use of the pesticides could not be entirely explained by lead originating from rock sulfides and their weathering products. An industrial lead contribution (mostly from atmospheric deposition of lead) was suggested in general to explain the lead isotopic distributions of the stream sediments that could not be accounted for by the natural lead in the environment. We concluded that when agricultural land previously contaminated with arsenical pesticides is urbanized, pesticide residues in the soils and stream sediments could be released into the groundwater. No lead isotopic data characterizing the compositions of pesticides were available for comparison. We have determined the lead isotopic compositions of commonly used pesticides in New England, such as lead arsenate, sodium metaarsenite, and calcium arsenate, in order to assist in future isotopic comparisons and to better establish anthropogenic sources of Pb and As. New data are also presented for copper acetoarsenite (or Paris green), methyl arsonic acid and methane arsonic acid, as well as for arsanilic acid, all of which are used as feed additives to promote swine and poultry growth

  9. Water-supply options in arsenic-affected regions in Cambodia: targeting the bottom income quintiles.

    Science.gov (United States)

    Chamberlain, Jim F; Sabatini, David A

    2014-08-01

    In arsenic-affected regions of Cambodia, rural water committees and planners can choose to promote various arsenic-avoidance and/or arsenic-removal water supply systems. Each of these has different costs of providing water, subsequently born by the consumer in order to be sustainable. On a volumetric basis ($/m3-yr) and of the arsenic-avoidance options considered, small-scale public water supply - e.g., treated water provided to a central tap stand - is the most expensive option on a life-cycle cost basis. Rainwater harvesting, protected hand dug wells, and vendor-supplied water are the cheapest with a normalized present worth value, ranging from $2 to $10 per cubic meter per year of water delivered. Subsidization of capital costs is needed to make even these options affordable to the lowest (Q5) quintile. The range of arsenic-removal systems considered here, using adsorptive media, is competitive with large-scale public water supply and deep tube well systems. Both community level and household-scale systems are in a range that is affordable to the Q4 quintile, though more research and field trials are needed. At a target cost of $5.00/m3, arsenic removal systems will compete with the OpEx costs for most of the arsenic-safe water systems that are currently available. The life-cycle cost approach is a valuable method for comparing alternatives and for assessing current water supply practices as these relate to equity and the ability to pay.

  10. Identification of a novel membrane transporter mediating resistance to organic arsenic in Campylobacter jejuni.

    Science.gov (United States)

    Shen, Zhangqi; Luangtongkum, Taradon; Qiang, Zhiyi; Jeon, Byeonghwa; Wang, Liping; Zhang, Qijing

    2014-01-01

    Although bacterial mechanisms involved in the resistance to inorganic arsenic are well understood, the molecular basis for organic arsenic resistance has not been described. Campylobacter jejuni, a major food-borne pathogen causing gastroenteritis in humans, is highly prevalent in poultry and is reportedly resistant to the arsenic compound roxarsone (4-hydroxy-3-nitrobenzenearsonic acid), which has been used as a feed additive in the poultry industry for growth promotion. In this study, we report the identification of a novel membrane transporter (named ArsP) that contributes to organic arsenic resistance in Campylobacter. ArsP is predicted to be a membrane permease containing eight transmembrane helices, distinct from other known arsenic transporters. Analysis of multiple C. jejuni isolates from various animal species revealed that the presence of an intact arsP gene is associated with elevated resistance to roxarsone. In addition, inactivation of arsP in C. jejuni resulted in 4- and 8-fold reductions in the MICs of roxarsone and nitarsone, respectively, compared to that for the wild-type strain. Furthermore, cloning of arsP into a C. jejuni strain lacking a functional arsP gene led to 16- and 64-fold increases in the MICs of roxarsone and nitarsone, respectively. Neither mutation nor overexpression of arsP affected the MICs of inorganic arsenic, including arsenite and arsenate, in Campylobacter. Moreover, acquisition of arsP in NCTC 11168 led to accumulation of less roxarsone than the wild-type strain lacking arsP. Together, these results indicate that ArsP functions as an efflux transporter specific for extrusion of organic arsenic and contributes to the resistance to these compounds in C. jejuni.

  11. Arsenic species excretion after dimercaptopropanesulfonic acid (DMPS) treatment of an acute arsenic trioxide poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Heinrich-Ramm, R. [Ordinariat fuer Arbeitsmedizin der Universitaet Hamburg und Zentralinstitut fuer Arbeitsmedizin, Hamburg (Germany); Schaller, K.H.; Angerer, J. [Institut und Poliklinik fuer Arbeits-, Sozial- und Umweltmedizin der Universitaet Erlangen-Nuernberg, Schillerstr. 25, 91054 Erlangen (Germany); Horn, J. [Medizinische Klinik II, Toxikologische-internistische Intensivstation, Klinikum Nuernberg, Nuernberg (Germany)

    2003-02-01

    We studied the urinary excretion of the different arsenic species in urine samples from a young man who tried to commit suicide by ingesting about 0.6 g arsenic trioxide. He received immediate therapy with dimercaptopropanesulfonic acid (DMPS) after his delivery into the hospital. We assessed urinary arsenite (inorganic trivalent arsenic), arsenate (inorganic pentavalent arsenic), pentavalent dimethylarsinic acid (DMA) and pentavalent monomethylarsonic acid (MMA) in urine with ion-exchange chromatography and on-line hydride-technique atomic absorption spectrometry. The predominant amount of the excreted arsenic was unchanged trivalent inorganic arsenic (37.4%), followed by pentavalent inorganic arsenic (2.6%), MMA (2.1%), DMA (0.2%) and one unidentified arsenic species (0.7%, if calculated as DMA). In the first urine voiding in the clinic, the total arsenic concentration was 215 mg/l, which fell 1000-fold after 8 days of DMPS therapy. A most striking finding was the almost complete inhibition of the second methylation step in arsenic metabolism. As mechanisms for the reduced methylation efficiency, the saturation of the enzymatic process of arsenic methylation, the high dosage of antidote DMPS, which might inhibit the activity of the methyl transferases, and analytical reasons are discussed. The high dosage of DMPS is the most likely explanation. The patient left the hospital after a 12-day treatment with antidote. (orig.)

  12. [Tracing for arsenic exposure--a differentiation of arsenic compounds is essential for the health assessment].

    Science.gov (United States)

    Weistenhöfer, Wobbeke; Ochsmann, Elke; Drexler, Hans; Göen, Thomas; Klotz, Katrin

    2016-01-01

    Arsenic is ubiquitous and harmful to health in occupation and environment. Arsenic exposure is measured through analysis of arsenic compounds in urine. The identification of several arsenic species is necessary to understand the hazardous potential of the arsenic compounds which differ highly in their toxicity. To estimate the extent of an occupational exposure to arsenic, arsenic species were evaluated for the first time by the working group "Setting of Threshold Limit Values in Biological Material" of the DFG Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area and Biologische Arbeitsstoffreferenzwerte (BAR) of 0.5 μg / L urine for arsenic (III), 0.5 μg / L urine for arsenic (V), 2 μg / L urine for monomethylarsonic acid (MMA) and 10 μg / L urine for dimethylarsinic acid (DMA) were set. If the reference value for total arsenic is exceeded, a further differentiation of arsenic species now enables to estimate the individual health risks taking into account special influences such as seafood consumption.

  13. Chromosome analysis of arsenic affected cattle

    Directory of Open Access Journals (Sweden)

    S. Shekhar

    2014-10-01

    Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

  14. Interactions between arsenic species and marine algae

    Energy Technology Data Exchange (ETDEWEB)

    Sanders, J.G.

    1978-01-01

    The arsenic concentration and speciation of marine algae varies widely, from 0.4 to 23 ng.mg/sup -1/, with significant differences in both total arsenic content and arsenic speciation occurring between algal classes. The Phaeophyceae contain more arsenic than other algal classes, and a greater proportion of the arsenic is organic. The concentration of inorganic arsenic is fairly constant in macro-algae, and may indicate a maximum level, with the excess being reduced and methylated. Phytoplankton take up As(V) readily, and incorporate a small percentage of it into the cell. The majority of the As(V) is reduced, methylated, and released to the surrounding media. The arsenic speciation in phytoplankton and Valonia also changes when As(V) is added to cultures. Arsenate and phosphate compete for uptake by algal cells. Arsenate inhibits primary production at concentrations as low as 5 ..mu..g.1/sup -1/ when the phosphate concentration is low. The inhibition is competitive. A phosphate enrichment of > 0.3 ..mu..M alleviates this inhibition; however, the As(V) stress causes an increase in the cell's phosphorus requirement. Arsenite is also toxic to phytoplankton at similar concentrations. Methylated arsenic species did not affect cell productivity, even at concentrations of 25 ..mu..g.1/sup -1/. Thus, the methylation of As(V) by the cell produces a stable, non-reactive compound which is nontoxic. The uptake and subsequent reduction and methylation of As(V) is a significant factor in determining the arsenic biogeochemistry of productive systems, and also the effect that the arsenic may have on algal productivity. Therefore, the role of marine algae in determining the arsenic speciation of marine systems cannot be ignored. (ERB)

  15. Arsenic Removal by Liquid Membranes

    Directory of Open Access Journals (Sweden)

    Tiziana Marino

    2015-03-01

    Full Text Available Water contamination with harmful arsenic compounds represents one of the most serious calamities of the last two centuries. Natural occurrence of the toxic metal has been revealed recently for 21 countries worldwide; the risk of arsenic intoxication is particularly high in Bangladesh and India but recently also Europe is facing similar problem. Liquid membranes (LMs look like a promising alternative to the existing removal processes, showing numerous advantages in terms of energy consumption, efficiency, selectivity, and operational costs. The development of different LM configurations has been a matter of investigation by several researching groups, especially for the removal of As(III and As(V from aqueous solutions. Most of these LM systems are based on the use of phosphine oxides as carriers, when the metal removal is from sulfuric acid media. Particularly promising for water treatment is the hollow fiber supported liquid membrane (HFSLM configuration, which offers high selectivity, easy transport of the targeted metal ions, large surface area, and non-stop flow process. The choice of organic extractant(s plays an essential role in the efficiency of the arsenic removal. Emulsion liquid membrane (ELM systems have not been extensively investigated so far, although encouraging results have started to appear in the literature. For such LM configuration, the most relevant step toward efficiency is the choice of the surfactant type and its concentration.

  16. Chronic arsenic poisoning from burning high-arsenic-containing coal in Guizhou, China.

    Science.gov (United States)

    Liu, Jie; Zheng, Baoshan; Aposhian, H Vasken; Zhou, Yunshu; Chen, Ming-Liang; Zhang, Aihua; Waalkes, Michael P

    2002-02-01

    Arsenic is an environmental hazard and the reduction of drinking water arsenic levels is under consideration. People are exposed to arsenic not only through drinking water but also through arsenic-contaminated air and food. Here we report the health effects of arsenic exposure from burning high arsenic-containing coal in Guizhou, China. Coal in this region has undergone mineralization and thus produces high concentrations of arsenic. Coal is burned inside the home in open pits for daily cooking and crop drying, producing a high concentration of arsenic in indoor air. Arsenic in the air coats and permeates food being dried producing high concentrations in food; however, arsenic concentrations in the drinking water are in the normal range. The estimated sources of total arsenic exposure in this area are from arsenic-contaminated food (50-80%), air (10-20%), water (1-5%), and direct contact in coal-mining workers (1%). At least 3,000 patients with arsenic poisoning were found in the Southwest Prefecture of Guizhou, and approximately 200,000 people are at risk for such overexposures. Skin lesions are common, including keratosis of the hands and feet, pigmentation on the trunk, skin ulceration, and skin cancers. Toxicities to internal organs, including lung dysfunction, neuropathy, and nephrotoxicity, are clinically evident. The prevalence of hepatomegaly was 20%, and cirrhosis, ascites, and liver cancer are the most serious outcomes of arsenic poisoning. The Chinese government and international organizations are attempting to improve the house conditions and the coal source, and thereby protect human health in this area.

  17. ARSENIC INDUCES SUSTAINED IMPAIRMENT OF SKELETAL MUSCLE AND MUSCLE PROGENITOR CELL ULTRASTRUCTURE AND BIOENERGETICS

    Science.gov (United States)

    Fabrisia, Ambrosio; Elke, Brown; Donna, Stolz; Ricardo, Ferrari; Bret, Goodpaster; Bridget, Deasy; Giovanna, Distefano; Alexandra, Roperti; Amin, Cheikhi; Yesica, Garciafigueroa; Aaron, Barchowsky

    2014-01-01

    Over 4 million individuals in the US, and over 140 million individuals worldwide, are exposed daily to arsenic-contaminated drinking water. Human exposures can range from below the current limit of 10 µg/L to over 1 mg/L, with 100 µg/L promoting disease in a large portion of those exposed. Although increased attention has recently been paid to myopathy following arsenic exposure, the pathogenic mechanisms underlying clinical symptoms remain poorly understood. This study tested the hypothesis that arsenic induces lasting muscle mitochondrial dysfunction and impairs metabolism. When compared to non-exposed controls, mice exposed to drinking water containing 100µg/L arsenite for 5 weeks demonstrated impaired muscle function, mitochondrial myopathy, and altered oxygen consumption that were concomitant with increased mitochondrial fusion gene transcription. There was no difference in levels of inorganic arsenic or its mononomethyl- and dimethyl- metabolites between controls and exposed muscles, confirming that arsenic does not accumulate in muscle. Nevertheless, muscle progenitor cells isolated from exposed mice recapitulated the aberrant myofiber phenotype and were more resistant to oxidative stress, generated more reactive oxygen species, and displayed autophagic mitochondrial morphology, as compared to cells isolated from non-exposed mice. These pathological changes from a possible maladaptive oxidative stress response provide insight into declines in muscle functioning caused by exposure to this common environmental contaminant. PMID:24960579

  18. A methodology for the sustainability assessment of arsenic mitigation technology for drinking water.

    Science.gov (United States)

    Etmannski, T R; Darton, R C

    2014-08-01

    In this paper we show how the process analysis method (PAM) can be applied to assess the sustainability of options to mitigate arsenic in drinking water in rural India. Stakeholder perspectives, gathered from a fieldwork survey of 933 households in West Bengal in 2012 played a significant role in this assessment. This research found that the 'most important' issues as specified by the technology users are cost, trust, distance from their home to the clean water source (an indicator of convenience), and understanding the health effects of arsenic. We show that utilisation of a technology is related to levels of trust and confidence in a community, making use of a composite trust-confidence indicator. Measures to improve trust between community and organisers of mitigation projects, and to raise confidence in technology and also in fair costing, would help to promote successful deployment of appropriate technology. Attitudes to cost revealed in the surveys are related to the low value placed on arsenic-free water, as also found by other investigators, consistent with a lack of public awareness about the arsenic problem. It is suggested that increased awareness might change attitudes to arsenic-rich waste and its disposal protocols. This waste is often currently discarded in an uncontrolled manner in the local environment, giving rise to the possibility of point-source recontamination.

  19. Bioaccumulation of Arsenic by Fungi

    Directory of Open Access Journals (Sweden)

    Ademola O. Adeyemi

    2009-01-01

    Full Text Available Problem statement: Arsenic is a known toxic element and its presence and toxicity in nature is a worldwide environmental problem. The use of microorganisms in bioremediation is a potential method to reduce as concentration in contaminated areas. Approach: In order to explore the possible bioremediation of this element, three filamentous fungi-Aspergillus niger, Serpula himantioides and Trametes versicolor were investigated for their potential abilities to accumulate (and possibly solubilize arsenic from an agar environment consisting of non buffered mineral salts media amended with 0.2, 0.4, 0.6 and 0.8% (w/v arsenopyrite (FeAsS. Growth rates, dry weights, arsenic accumulation and oxalate production by the fungi as well as the pH of the growth media were all assessed during this study. Results: There was no visible solubilization of FeAsS particles underneath any of the growing fungal colonies or elsewhere in the respective agar plates. No specific patterns of growth changes were observed from the growth ratios of the fungi on agar amended with different amounts of FeAsS although growth of all fungi was stimulated by the incorporation of varying amounts of FeAsS into the agar with the exception of A. niger on 0.4% (w/v amended agar and T. versicolor on 0.8% (w/v amended agar. The amounts of dry weights obtained for all three fungi also did not follow any specific patterns with different amounts of FeAsS and the quantities obtained were in the order A. niger > S. himantioides > T. versicolor. All fungi accumulated as in their biomasses with all amounts of FeAsS although to varying levels and T. versicolor was the most effective with all amounts of FeAsS while A. niger was the least effective. Conclusion: The accumulation of arsenic in the biomasses of the test fungi as shown in this study may suggested a role for fungi through their bioaccumulating capabilities as agents in the possible bioremediation of arsenic contaminated environments.

  20. Biotechnology based processes for arsenic removal

    NARCIS (Netherlands)

    Huisman, J.; Olde Weghuis, M.; Gonzalez-Contreras, P.A.

    2011-01-01

    The regulations for arsenic control have become strict. Therefore, better technologies to remove arsenic from bleeds and effluents are desired. In addition, no single solution is suitable for all cases. The properties of the process streams and the storage facilities are major factors determining th

  1. 29 CFR 1926.1118 - Inorganic arsenic.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Inorganic arsenic. 1926.1118 Section 1926.1118 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... Inorganic arsenic. Note: The requirements applicable to construction work under this section are...

  2. 29 CFR 1915.1018 - Inorganic arsenic.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Inorganic arsenic. 1915.1018 Section 1915.1018 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... § 1915.1018 Inorganic arsenic. Note: The requirements applicable to shipyard employment under...

  3. 29 CFR 1910.1018 - Inorganic arsenic.

    Science.gov (United States)

    2010-07-01

    ...) Engineering plans and studies used to determine methods selected for controlling exposure to inorganic arsenic... such exposures. The following three sections quoted from “Occupational Diseases: A Guide to Their.... Arsenic; chronic human intoxication. J. Occup. Med. 2:137. Elkins, H. B. 1959. The Chemistry of...

  4. Hijacking membrane transporters for arsenic phytoextraction.

    Science.gov (United States)

    LeBlanc, Melissa S; McKinney, Elizabeth C; Meagher, Richard B; Smith, Aaron P

    2013-01-10

    Arsenic is a toxic metalloid and recognized carcinogen. Arsenate and arsenite are the most common arsenic species available for uptake by plants. As an inorganic phosphate (Pi) analog, arsenate is acquired by plant roots through endogenous Pi transport systems. Inside the cell, arsenate is reduced to the thiol-reactive form arsenite. Glutathione (GSH)-conjugates of arsenite may be extruded from the cell or sequestered in vacuoles by members of the ATP-binding cassette (ABC) family of transporters. In the present study we sought to enhance both plant arsenic uptake through Pi transporter overexpression, and plant arsenic tolerance through ABC transporter overexpression. We demonstrate that Arabidopsis thaliana plants overexpressing the high-affinity Pi transporter family members, AtPht1;1 or AtPht1;7, are hypersensitive to arsenate due to increased arsenate uptake. These plants do not exhibit increased sensitivity to arsenite. Co-overexpression of the yeast ABC transporter YCF1 in combination with AtPht1;1 or AtPht1;7 suppresses the arsenate-sensitive phenotype while further enhancing arsenic uptake. Taken together, our results support an arsenic transport mechanism in which arsenate uptake is increased through Pi transporter overexpression, and arsenic tolerance is enhanced through YCF1-mediated vacuolar sequestration. This work substantiates the viability of coupling enhanced uptake and vacuolar sequestration as a means for developing a prototypical engineered arsenic hyperaccumulator.

  5. Arsenic and human health effects: A review.

    Science.gov (United States)

    Abdul, Khaja Shameem Mohammed; Jayasinghe, Sudheera Sammanthi; Chandana, Ediriweera P S; Jayasumana, Channa; De Silva, P Mangala C S

    2015-11-01

    Arsenic (As) is ubiquitous in nature and humans being exposed to arsenic via atmospheric air, ground water and food sources are certain. Major sources of arsenic contamination could be either through geological or via anthropogenic activities. In physiological individuals, organ system is described as group of organs that transact collectively and associate with other systems for conventional body functions. Arsenic has been associated with persuading a variety of complications in body organ systems: integumentary, nervous, respiratory, cardiovascular, hematopoietic, immune, endocrine, hepatic, renal, reproductive system and development. In this review, we outline the effects of arsenic on the human body with a main focus on assorted organ systems with respective disease conditions. Additionally, underlying mechanisms of disease development in each organ system due to arsenic have also been explored. Strikingly, arsenic has been able to induce epigenetic changes (in utero) and genetic mutations (a leading cause of cancer) in the body. Occurrence of various arsenic induced health effects involving emerging areas such as epigenetics and cancer along with their respective mechanisms are also briefly discussed.

  6. ARSENIC EFFECTS ON TELOMERE AND TELOMERASE ACTIVITY

    Science.gov (United States)

    Arsenic effects on telomere and telomerase activity. T-C. Zhang, M. T. Schmitt, J. Mo, J. L. Mumford, National Research Council and U.S Environmental Protection Agency, NHEERL, Research Triangle Park, NC 27711Arsenic is a known carcinogen and also an anticancer agent for acut...

  7. Arsenic pesticides and environmental pollution: exposure, poisoning, hazards and recommendations.

    Science.gov (United States)

    El-Bahnasawy, Mamdouh M; Mohammad, Amina El-Hosini; Morsy, Tosson A

    2013-08-01

    Arsenic is a metalloid element. Acute high-dose exposure to arsenic can cause severe systemic toxicity and death. Lower dose chronic arsenic exposure can result in subacute toxicity that can include peripheral sensorimotor neuropathy, skin eruptions, and hepatotoxicity. Long-term effects of arsenic exposure include an in Due to the physiologic effects of the arsenic on all body systems, thus, chronic arsenic-poisoned patient is a major nursing challenge. The critical care nurse provides valuable assessment and interventions that prevent major multisystem complications from arsenic toxicity.

  8. Arsenic Uptake by Muskmelon (Cucumis melo) Plants from Contaminated Water.

    Science.gov (United States)

    Hettick, Bryan E; Cañas-Carrell, Jaclyn E; Martin, Kirt; French, Amanda D; Klein, David M

    2016-09-01

    Arsenic is a carcinogenic element that occurs naturally in the environment. High levels of arsenic are found in water in some parts of the world, including Texas. The aims of this study were to determine the distribution of arsenic in muskmelon (Cucumis melo) plants accumulated from arsenic spiked water and to observe effects on plant biomass. Plants were grown and irrigated using water spiked with variable concentrations of arsenic. Inductively coupled plasma mass spectrometry was used to quantify arsenic in different parts of the plant and fruit. Under all conditions tested in this study, the highest concentrations of arsenic were found in the leaves, soil, and roots. Arsenic in the water had no significant effect on plant biomass. Fruits analyzed in this study had arsenic concentrations of 101 μg/kg or less. Consuming these fruits would result in less arsenic exposure than drinking water at recommended levels.

  9. Arsenic burden survey among refuse incinerator workers

    Directory of Open Access Journals (Sweden)

    Chao Chung-Liang

    2005-01-01

    Full Text Available Background: Incinerator workers are not considered to have arsenic overexposure although they have the risk of overexposure to other heavy metals. Aim: To examine the relationship between arsenic burden and risk of occupational exposure in employees working at a municipal refuse incinerator by determining the concentrations of arsenic in the blood and urine. Settings and Design: The workers were divided into three groups based on their probability of contact with combustion-generated residues, namely Group 1: indirect contact, Group 2: direct contact and Group 3: no contact. Healthy age- and sex-matched residents living in the vicinity were enrolled as the control group. Materials and Methods: Heavy metal concentrations were measured by atomic absorption spectrophotometer. Downstream rivers and drinking water of the residents were examined for environmental arsenic pollution. A questionnaire survey concerning the contact history of arsenic was simultaneously conducted. Statistical analysis: Non-parametric tests, cross-tabulation and multinomial logistic regression. Results: This study recruited 122 incinerator workers. The urine and blood arsenic concentrations as well as incidences of overexposure were significantly higher in the workers than in control subjects. The workers who had indirect or no contact with combustion-generated residues had significantly higher blood arsenic level. Arsenic contact history could not explain the difference. Airborne and waterborne arsenic pollution were not detected. Conclusion: Incinerator workers run the risk of being exposed to arsenic pollution, especially those who have incomplete protection in the workplace even though they only have indirect or no contact with combustion-generated pollutants.

  10. Both Phosphorus Fertilizers and Indigenous Bacteria Enhance Arsenic Release into Groundwater in Arsenic-Contaminated Aquifers.

    Science.gov (United States)

    Lin, Tzu-Yu; Wei, Chia-Cheng; Huang, Chi-Wei; Chang, Chun-Han; Hsu, Fu-Lan; Liao, Vivian Hsiu-Chuan

    2016-03-23

    Arsenic (As) is a human carcinogen, and arsenic contamination in groundwater is a worldwide public health concern. Arsenic-affected areas are found in many places but are reported mostly in agricultural farmlands, yet the interaction of fertilizers, microorganisms, and arsenic mobilization in arsenic-contaminated aquifers remains uncharacterized. This study investigates the effects of fertilizers and bacteria on the mobilization of arsenic in two arsenic-contaminated aquifers. We performed microcosm experiments using arsenic-contaminated sediments and amended with inorganic nitrogenous or phosphorus fertilizers for 1 and 4 months under aerobic and anaerobic conditions. The results show that microcosms amended with 100 mg/L phosphorus fertilizers (dipotassium phosphate), but not nitrogenous fertilizers (ammonium sulfate), significantly increase aqueous As(III) release in arsenic-contaminated sediments under anaerobic condition. We also show that concentrations of iron, manganese, potassium, sodium, calcium, and magnesium are increased in the aqueous phase and that the addition of dipotassium phosphate causes a further increase in aqueous iron, potassium, and sodium, suggesting that multiple metal elements may take part in the arsenic release process. Furthermore, microbial analysis indicates that the dominant microbial phylum is shifted from α-proteobacteria to β- and γ-proteobacteria when the As(III) is increased and phosphate is added in the aquifer. Our results provide evidence that both phosphorus fertilizers and microorganisms can mediate the release of arsenic to groundwater in arsenic-contaminated sediments under anaerobic condition. Our study suggests that agricultural activity such as the use of fertilizers and monitoring phosphate concentration in groundwater should be taken into consideration for the management of arsenic in groundwater.

  11. Factors Affecting Arsenic Methylation in Arsenic-Exposed Humans: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Hui Shen

    2016-02-01

    Full Text Available Chronic arsenic exposure is a critical public health issue in many countries. The metabolism of arsenic in vivo is complicated because it can be influenced by many factors. In the present meta-analysis, two researchers independently searched electronic databases, including the Cochrane Library, PubMed, Springer, Embase, and China National Knowledge Infrastructure, to analyze factors influencing arsenic methylation. The concentrations of the following arsenic metabolites increase (p< 0.000001 following arsenic exposure: inorganic arsenic (iAs, monomethyl arsenic (MMA, dimethyl arsenic (DMA, and total arsenic. Additionally, the percentages of iAs (standard mean difference (SMD: 1.00; 95% confidence interval (CI: 0.60–1.40; p< 0.00001 and MMA (SMD: 0.49; 95% CI: 0.21–0.77; p = 0.0006 also increase, while the percentage of DMA (SMD: −0.57; 95% CI: −0.80–−0.31; p< 0.0001, primary methylation index (SMD: −0.57; 95% CI: −0.94–−0.20; p = 0.002, and secondary methylation index (SMD: −0.27; 95% CI: −0.46–−0.90; p = 0.004 decrease. Smoking, drinking, and older age can reduce arsenic methylation, and arsenic methylation is more efficient in women than in men. The results of this analysis may provide information regarding the role of arsenic oxidative methylation in the arsenic poisoning process.

  12. Evaluation of Exposure to Arsenic in Residential Soil

    OpenAIRE

    Tsuji, JS; Van Kerkhove, MD; Kaetzel, RS; Scrafford, CG; Mink, PJ; Barraj, LM; Crecelius, EA; Goodman, M.

    2005-01-01

    In response to concerns regarding arsenic in soil from a pesticide manufacturing plant, we conducted a biomonitoring study on children younger than 7 years of age, the age category of children most exposed to soil. Urine samples from 77 children (47% participation rate) were analyzed for total arsenic and arsenic species related to ingestion of inorganic arsenic. Older individuals also provided urine (n = 362) and toenail (n = 67) samples. Speciated urinary arsenic levels were similar between...

  13. Cellular distribution of arsenic and other elements in hyperaccumulator Pteris nervosa and their relations to arsenic accumulation

    Institute of Scientific and Technical Information of China (English)

    CHEN Tongbin; HUANG Zechun; HUANG Yuying; XIE Hua; LIAO Xiaoyong

    2003-01-01

    Synchrotron radiation X-ray fluorescencespectroscopy (SRXRF) was used to study the cellular distri-butions of arsenic and other elements in root, petiole, pinna of a newly discovered arsenic hyperaccumulator, Pteris nervosa. It was shown that there was a trend in P. nervosa totransport arsenic from cortex tissue to vascular tissue in root, and keep arsenic in vascular during transportation in petiole, and transport arsenic from vascular tissue to adaxial cortex tissues in midrib of pinnae. More arsenic was accumulated in mesophyll than in epidermis in pinnae. The distributions of some elements, such as K, Ca, Mn, Fe, Cu, Zn, in petiole, midrib and pinna were similar to that of arsenic, indicating that those cations might cooperate with arsenic in those transportation processes; whereas the distributions of Cl and Br in pinna were the reverse of that of arsenic, indicating that those anions might compete with arsenic in pinna of P. nervosa.

  14. Geostatistical modelling of arsenic in drinking water wells and related toenail arsenic concentrations across Nova Scotia, Canada.

    Science.gov (United States)

    Dummer, T J B; Yu, Z M; Nauta, L; Murimboh, J D; Parker, L

    2015-02-01

    Arsenic is a naturally occurring class 1 human carcinogen that is widespread in private drinking water wells throughout the province of Nova Scotia in Canada. In this paper we explore the spatial variation in toenail arsenic concentrations (arsenic body burden) in Nova Scotia. We describe the regional distribution of arsenic concentrations in private well water supplies in the province, and evaluate the geological and environmental features associated with higher levels of arsenic in well water. We develop geostatistical process models to predict high toenail arsenic concentrations and high well water arsenic concentrations, which have utility for studies where no direct measurements of arsenic body burden or arsenic exposure are available. 892 men and women who participated in the Atlantic Partnership for Tomorrow's Health Project provided both drinking water and toenail clipping samples. Information on socio-demographic, lifestyle and health factors was obtained with a set of standardized questionnaires. Anthropometric indices and arsenic concentrations in drinking water and toenails were measured. In addition, data on arsenic concentrations in 10,498 private wells were provided by the Nova Scotia Department of Environment. We utilised stepwise multivariable logistic regression modelling to develop separate statistical models to: a) predict high toenail arsenic concentrations (defined as toenail arsenic levels ≥0.12 μg g(-1)) and b) predict high well water arsenic concentrations (defined as well water arsenic levels ≥5.0 μg L(-1)). We found that the geological and environmental information that predicted well water arsenic concentrations can also be used to accurately predict toenail arsenic concentrations. We conclude that geological and environmental factors contributing to arsenic contamination in well water are the major contributing influences on arsenic body burden among Nova Scotia residents. Further studies are warranted to assess appropriate

  15. A greenhouse study on arsenic remediation potential of Vetiver grass (Vetiveria Zizanioides) as a function of soil physico-chemical properties

    Science.gov (United States)

    Quispe, M. A.; Datta, R.; Sarkar, D.; Sharma, S.

    2006-05-01

    Arsenic is one of the most harmful and toxic metals, being a Group A human carcinogen. Mining activities as well as the use of arsenic-containing pesticides have resulted in the contamination of a wide variety of sites including mine tailings, cattle dip sites, wood treatment sites, pesticide treatment areas, golf courses, etc. Phytoremediation has emerged as a novel and promising technology, which uses plants to clean up contaminated soil and water taking advantage of plant's natural abilities to extract and accumulate various contaminants. This method has distinct advantages, since it maintains the biological properties and physical structure of the soil, is environment friendly, and above all, inexpensive. However, effective remediation of contaminated residential soils using a specific plant species is an immensely complex task whose success depends on a multitude of factors including the ability of the target plant to uptake, translocate, detoxify, and accumulate arsenic in its system. One of the major challenges in phytoremediation lies in identifying a fast- growing, high biomass plant that can accumulate the contaminant in its harvestable parts. vetiver grass (Vetiveria zizanioides) is a fast-growing perennial grass with strong ecological adaptability and large biomass. While this plant is not a hyperaccumulator of arsenic, it has been reported to be able to tolerate and accumulate considerable amounts of arsenic. Being a high biomass, fast-growing plant, vetiver has the potential to be used for arsenic remediation. The present study investigates the potential of vetiver grass to tolerate and accumulate arsenic in soils with varying physico-chemical properties. A greenhouse study is in progress to study the uptake, tolerance and stress response of vetiver grass to inorganic arsenical pesticide. A column study was set up using 5 soils (Eufaula, Millhopper, Orelia, Orla, and Pahokee Muck) contaminated with sodium arsenite at 4 different concentrations of

  16. Arsenic Induction of Metallothionein and Metallothionein Induction Against Arsenic Cytotoxicity.

    Science.gov (United States)

    Rahman, Mohammad Tariqur; De Ley, Marc

    Human exposure to arsenic (As) can lead to oxidative stress that can become evident in organs such as the skin, liver, kidneys and lungs. Several intracellular antioxidant defense mechanisms including glutathione (GSH) and metallothionein (MT) have been shown to minimize As cytotoxicity. The current review summarizes the involvement of MT as an intracellular defense mechanism against As cytotoxicity, mostly in blood. Zinc (Zn) and selenium (Se) supplements are also proposed as a possible remediation of As cytotoxicity. In vivo and in vitro studies on As toxicity were reviewed to summarize cytotoxic mechanisms of As. Intracellular antioxidant defense mechanisms of MT are linked in relation to As cytotoxicity. Arsenic uses a different route, compared to major metal MT inducers such as Zn, to enter/exit blood cells. A number of in vivo and in vitro studies showed that upregulated MT biosynthesis in blood components are related to toxic levels of As. Despite the cysteine residues in MT that aid to bind As, MT is not the preferred binding protein for As. Nonetheless, intracellular oxidative stress due to As toxicity can be minimized, if not eliminated, by MT. Thus MT induction by essential metals such as Zn and Se supplementation could be beneficial to fight against As toxicity.

  17. Systematic identification of arsenic-binding proteins reveals that hexokinase-2 is inhibited by arsenic.

    Science.gov (United States)

    Zhang, Hai-Nan; Yang, Lina; Ling, Jian-Ya; Czajkowsky, Daniel M; Wang, Jing-Fang; Zhang, Xiao-Wei; Zhou, Yi-Ming; Ge, Feng; Yang, Ming-Kun; Xiong, Qian; Guo, Shu-Juan; Le, Huang-Ying; Wu, Song-Fang; Yan, Wei; Liu, Bingya; Zhu, Heng; Chen, Zhu; Tao, Sheng-Ce

    2015-12-01

    Arsenic is highly effective for treating acute promyelocytic leukemia (APL) and has shown significant promise against many other tumors. However, although its mechanistic effects in APL are established, its broader anticancer mode of action is not understood. In this study, using a human proteome microarray, we identified 360 proteins that specifically bind arsenic. Among the most highly enriched proteins in this set are those in the glycolysis pathway, including the rate-limiting enzyme in glycolysis, hexokinase-1. Detailed biochemical and metabolomics analyses of the highly homologous hexokinase-2 (HK2), which is overexpressed in many cancers, revealed significant inhibition by arsenic. Furthermore, overexpression of HK2 rescued cells from arsenic-induced apoptosis. Our results thus strongly implicate glycolysis, and HK2 in particular, as a key target of arsenic. Moreover, the arsenic-binding proteins identified in this work are expected to serve as a valuable resource for the development of synergistic antitumor therapeutic strategies.

  18. Arsenic Metabolites, Including N-Acetyl-4-hydroxy-m-arsanilic Acid, in Chicken Litter from a Roxarsone-Feeding Study Involving 1600 Chickens.

    Science.gov (United States)

    Yang, Zonglin; Peng, Hanyong; Lu, Xiufen; Liu, Qingqing; Huang, Rongfu; Hu, Bin; Kachanoski, Gary; Zuidhof, Martin J; Le, X Chris

    2016-07-01

    The poultry industry has used organoarsenicals, such as 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone, ROX), to prevent disease and to promote growth. Although previous studies have analyzed arsenic species in chicken litter after composting or after application to agricultural lands, it is not clear what arsenic species were excreted by chickens before biotransformation of arsenic species during composting. We describe here the identification and quantitation of arsenic species in chicken litter repeatedly collected on days 14, 24, 28, 30, and 35 of a Roxarsone-feeding study involving 1600 chickens of two strains. High performance liquid chromatography separation with simultaneous detection by both inductively coupled plasma mass spectrometry and electrospray ionization tandem mass spectrometry provided complementary information necessary for the identification and quantitation of arsenic species. A new metabolite, N-acetyl-4-hydroxy-m-arsanilic acid (N-AHAA), was identified, and it accounted for 3-12% of total arsenic. Speciation analyses of litter samples collected from ROX-fed chickens on days 14, 24, 28, 30, and 35 showed the presence of N-AHAA, 3-amino-4-hydroxyphenylarsonic acid (3-AHPAA), inorganic arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA(V)), dimethylarsinic acid (DMA(V)), and ROX. 3-AHPAA accounted for 3-19% of the total arsenic. Inorganic arsenicals (the sum of As(III) and As(V)) comprised 2-6% (mean 3.5%) of total arsenic. Our results on the detection of inorganic arsenicals, methylarsenicals, 3-AHPAA, and N-AHAA in the chicken litter support recent findings that ROX is actually metabolized by the chicken or its gut microbiome. The presence of the toxic metabolites in chicken litter is environmentally relevant as chicken litter is commonly used as fertilizer.

  19. Arsenic-Induced Antioxidant Depletion, Oxidative DNA Breakage, and Tissue Damages are Prevented by the Combined Action of Folate and Vitamin B12.

    Science.gov (United States)

    Acharyya, Nirmallya; Deb, Bimal; Chattopadhyay, Sandip; Maiti, Smarajit

    2015-11-01

    Arsenic is a grade I human carcinogen. It acts by disrupting one-carbon (1C) metabolism and cellular methyl (-CH3) pool. The -CH3 group helps in arsenic disposition and detoxification of the biological systems. Vitamin B12 and folate, the key promoters of 1C metabolism were tested recently (daily 0.07 and 4.0 μg, respectively/100 g b.w. of rat for 28 days) to evaluate their combined efficacy in the protection from mutagenic DNA-breakage and tissue damages. The selected tissues like intestine (first-pass site), liver (major xenobiotic metabolizer) and lung (major arsenic accumulator) were collected from arsenic-ingested (0.6 ppm/same schedule) female rats. The hemo-toxicity and liver and kidney functions were monitored. Our earlier studies on arsenic-exposed humans can correlate carcinogenesis with DNA damage. Here, we demonstrate that the supplementation of physiological/therapeutic dose of vitamin B12 and folate protected the rodents significantly from arsenic-induced DNA damage (DNA fragmentation and comet assay) and hepatic and renal tissue degeneration (histo-architecture, HE staining). The level of arsenic-induced free-radical products (TBARS and conjugated diene) was significantly declined by the restored actions of several antioxidants viz. urate, thiol, catalase, xanthine oxidase, lactoperoxidase, and superoxide dismutase in the tissues of vitamin-supplemented group. The alkaline phosphatase, transaminases, urea and creatinine (hepatic and kidney toxicity marker), and lactate dehydrogenase (tissue degeneration marker) were significantly impaired in the arsenic-fed group. But a significant protection was evident in the vitamin-supplemented group. In conclusion, the combined action of folate and B12 results in the restitution in the 1C metabolic pathway and cellular methyl pool. The cumulative outcome from the enhanced arsenic methylation and antioxidative capacity was protective against arsenic induced mutagenic DNA breakages and tissue damages.

  20. Social implications of arsenic poisoning in Bangladesh.

    Science.gov (United States)

    Hassan, M Manzurul; Atkins, Peter J; Dunn, Christine E

    2005-11-01

    Besides its toxicity, groundwater arsenic contamination creates widespread social problems for its victims and their families in Bangladesh. There is, for instance, a tendency to ostracise arsenic-affected people, arsenicosis being thought of as a contagious disease. Within the community, arsenic-affected people are barred from social activities and often face rejection, even by their immediate family members. Women with visible arsenicosis symptoms are unable to get married and some affected housewives are divorced by their husbands. Children with symptoms are not sent to school in an effort to hide the problem. This paper employs mainly qualitative methods to interpret people's understandings about the toxic impact of groundwater arsenic poisoning on their social lives. Arsenic-affected patients in southwest Bangladesh were asked to determine their 'own priorities' in measuring arsenic toxicity on their social activities and to explore their perceptions about their own survival strategies. We found that patients' experiences reveal severe negative social impacts, and a sharp difference of perceptions about arsenic and social issues between arsenicosis patients and unaffected people.

  1. [Competitive Microbial Oxidation and Reduction of Arsenic].

    Science.gov (United States)

    Yang, Ting-ting; Bai, Yao-hui; Liang, Jin-song; Huo, Yang; Wang, Ming-xing; Yuan, Lin-ijang

    2016-02-15

    Filters are widely applied in drinking water treatment plants. Our previous study, which explored the asenic redox in a filter of drinking water plant treating underground water, found that As3+ could be oxidized to As5+ by biogenic manganese oxides, while As5+ could be reduced to As3+ by some microbial arsenic reductases in the biofilter system. This microbial competition could influence the system stability and treatment efficiency. To explore its mechanism, this study selected a manganese-oxidizing bacterial strain (Pseudomonas sp. QJX-1) and a arsenic-reducing strain (Brevibacterium sp. LSJ-9) to investigate their competitive relationship in nutrient acquisition and arsenic redox in the presence of Mn2+, As3+ or As5+ The results revealed that the concentration and valence of Mn and As varied with different reaction time; biological manganese oxides dominated the arsenic redox by rapidly oxidizing the As3+ in the existing system and the As3+ generated by arsenic reductase into As. PCR and RT-PCR results indicated that the arsenic reductase (arsC) was inhibited by the manganese oxidase (cumA). The expression of 16S rRNA in QJX-1 was two orders of magnitude higher than that in LSJ-9, which implied QJX-1 was dominant in the bacterial growth. Our data revealed that hydraulic retention time was critical to the valence of arsenic in the effluent of filter in drinking water treatment plant.

  2. Identification of an Arsenic Resistance and Arsenic-Sensing System in Campylobacter jejuni▿ †

    OpenAIRE

    Wang, Liping; Jeon, Byeonghwa; Sahin, Orhan; Zhang, Qijing

    2009-01-01

    Arsenic is commonly present in the natural environment and is also used as a feed additive for animal production. Poultry is a major reservoir for Campylobacter jejuni, a major food-borne human pathogen causing gastroenteritis. It has been shown that Campylobacter isolates from poultry are highly resistant to arsenic compounds, but the molecular mechanisms responsible for the resistance have not been determined, and it is unclear if the acquired arsenic resistance affects the susceptibility o...

  3. Arsenic adsorption of lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil

    Directory of Open Access Journals (Sweden)

    Wuthiphun, L.

    2007-05-01

    Full Text Available Arsenic adsorption efficiency of soil covering materials (lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil obtained from Ronpiboon District, Nakhon Sri Thammarat Province tosolve arsenic air pollution problem was investigated using batch experiments. The four types of the aforementioned soil covering materials were examined to determine their arsenic adsorption efficiency, equilibriumtime as well as adsorption isotherms.The results revealed that among soil covering materials mixed with arsenic-contaminated soil at 10% w/w, the efficiency of arsenic adsorption of fly ash, lateritic soil, lime and limestone powder were 84, 60,38 and 1% respectively. The equilibrium time for lateritic soil at pH 4 was achieved within 4 hrs, whereas pH 7 and 12, the equilibrium time was 6 hrs. For fly ash, 2 hrs were required to reach the equilibrium at pH 12, while the equilibrium time was attained within 6 hrs at pH 4 and 7. Furthermore, lateritic soil possessedhigh arsenic adsorption efficiency at pH 7 and 4 and best fit with the Langmuir isotherm. The fly ash showing high arsenic adsorption efficiency at pH 12 and 7 fit the Freundlich isotherm at pH 12 and Langmuirisotherm at pH 7.This indicated that lateritic soil was suitable for arsenic adsorption at low pH, whilst at high pH,arsenic was well adsorbed by fly ash. The Freundlich and Langmuir isotherm could be used to determine quantities of soil covering materials for arsenic adsorption to prevent arsenic air pollution from arseniccontaminated soils.

  4. Arsenic in North Carolina: public health implications.

    Science.gov (United States)

    Sanders, Alison P; Messier, Kyle P; Shehee, Mina; Rudo, Kenneth; Serre, Marc L; Fry, Rebecca C

    2012-01-01

    Arsenic is a known human carcinogen and relevant environmental contaminant in drinking water systems. We set out to comprehensively examine statewide arsenic trends and identify areas of public health concern. Specifically, arsenic trends in North Carolina private wells were evaluated over an eleven-year period using the North Carolina Department of Health and Human Services database for private domestic well waters. We geocoded over 63,000 domestic well measurements by applying a novel geocoding algorithm and error validation scheme. Arsenic measurements and geographical coordinates for database entries were mapped using Geographic Information System techniques. Furthermore, we employed a Bayesian Maximum Entropy (BME) geostatistical framework, which accounts for geocoding error to better estimate arsenic values across the state and identify trends for unmonitored locations. Of the approximately 63,000 monitored wells, 7712 showed detectable arsenic concentrations that ranged between 1 and 806μg/L. Additionally, 1436 well samples exceeded the EPA drinking water standard. We reveal counties of concern and demonstrate a historical pattern of elevated arsenic in some counties, particularly those located along the Carolina terrane (Carolina slate belt). We analyzed these data in the context of populations using private well water and identify counties for targeted monitoring, such as Stanly and Union Counties. By spatiotemporally mapping these data, our BME estimate revealed arsenic trends at unmonitored locations within counties and better predicted well concentrations when compared to the classical kriging method. This study reveals relevant information on the location of arsenic-contaminated private domestic wells in North Carolina and indicates potential areas at increased risk for adverse health outcomes.

  5. The Effect of Thiosulphate on Arsenic Bioavailability in a Multi Contaminated Soil. A Novel Contribution to Phytoextraction

    Directory of Open Access Journals (Sweden)

    Gianniantonio Petruzzelli

    2014-01-01

    Full Text Available In this study it was evaluated on a laboratory scale (microcosm, the possibility of using ammonium thiosulphate in assisted phytoextraction for the simultaneous removal of mercury and arsenic from multi-contaminated industrial soil. The species selected were Brassica juncea and Lupinus albus the addition of thiosulfate to the soil greatly promoted the uptake and translocation of both contaminants in the aerial parts of the plants. Mercury concentration in the aerial parts reached in B. juncea 120 mg/kg approximately 40 times the value of the control. The concentration of arsenic also increased significantly in the shoots of B. juncea (14.3 mg/kg, where the value in the control was negligible. Similar trends were obtained for L. albus The results confirmed the known positive effects of thiosulphate in increasing mercury bioavailability for plants, moreover they showed the ability of thiosulphate to mobilize arsenic and significantly to promote its uptake by plants. The increase of arsenic bioavailability, promoted by thiosulfate addition, could be attributed to the competition between arsenate and sulphate ions for the same active sites in the soil surfaces, with the release of arsenic in the soil solution. The use of thiosulfate appears to have great potential since it is a common fertilizer used to promote plant growth and is able to increase the uptake by plants of mercury and arsenic. The simultaneous increase of both contaminants uptake by plants, using a single additive, will provide new insights into the phytoextraction technology in terms of cost and time reduction.

  6. Determination of total arsenic, inorganic and organic arsenic species in wine.

    Science.gov (United States)

    Herce-Pagliai, C; Moreno, I; González, G; Repetto, M; Cameán, A M

    2002-06-01

    Forty-five wine samples from the south of Spain of different alcoholic strength were analysed for total arsenic and its inorganic [As(III), As(V)] and organic (monomethylarsonic acid [MMAA], dimethylarsinic acid [DMAA]) species. The As levels of the wine samples ranged from 2.1 to 14.6 microg l(-1). The possible effect of the alcoholic fermentation process on the levels of the total arsenic and arsenical species was studied. The average total arsenic levels for the different samples were very similar, without significant differences between all types of wines. In table wines and sherry, the percentages of total inorganic arsenic were 18.6 and 15.6%, with DMAA or MMAA being the predominant species, respectively. In most samples, DMAA was the most abundant species, but the total inorganic aresenic fraction was considerable, representing 25.4% of the total concentration of the element. The estimated daily intakes of total arsenic and total inorganic arsenic for average Spanish consumers were 0.78 and 0.15 microg/person day(-1), respectively. The results suggest that the consumption of these types of wines makes no significant contribution to the total and inorganic arsenic intake for normal drinkers. However, wine consumption contributes a higher arsenic intake than through consumption of beers and sherry brandies.

  7. Electrochemical arsenic remediation for rural Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Addy, Susan Amrose [Univ. of California, Berkeley, CA (United States)

    2008-01-01

    Arsenic in drinking water is a major public health problem threatening the lives of over 140 million people worldwide. In Bangladesh alone, up to 57 million people drink arsenic-laden water from shallow wells. ElectroChemical Arsenic Remediation(ECAR) overcomes many of the obstacles that plague current technologies and can be used affordably and on a small-scale, allowing for rapid dissemination into Bangladesh to address this arsenic crisis. In this work, ECAR was shown to effectively reduce 550 - 580 μg=L arsenic (including both As[III]and As[V]in a 1:1 ratio) to below the WHO recommended maximum limit of 10 μg=L in synthetic Bangladesh groundwater containing relevant concentrations of competitive ions such as phosphate, silicate, and bicarbonate. Arsenic removal capacity was found to be approximately constant within certain ranges of current density, but was found to change substantially between ranges. In order of decreasing arsenic removal capacity, the pattern was: 0.02 mA=cm2> 0.07 mA=cm2> 0.30 - 1.1 mA=cm2> 5.0 - 100 mA=cm2. Current processing time was found to effect arsenic removal capacity independent of either charge density or current density. Electrode polarization studies showed no passivation of the electrode in the tested range (up to current density 10 mA=cm2) and ruled out oxygen evolution as the cause of decreasing removal capacity with current density. Simple settling and decantation required approximately 3 days to achieve arsenic removal comparable to filtration with a 0.1 mu m membrane. X-ray Absorption Spectroscopy (XAS) showed that (1) there is no significant difference in the arsenic removal mechanism of ECAR during operation at different current densities and (2) the arsenic removal mechanism in ECAR is consistent with arsenate adsorption onto a homogenous Fe(III)oxyhydroxide similar in structure to 2-line ferrihydrite. ECAR effectively reduced high arsenic concentrations (100

  8. Arsenic in rice: A cause for concern

    DEFF Research Database (Denmark)

    Hojsak, Iva; Braegger, Christian; Bronsky, Jiri

    2015-01-01

    Inorganic arsenic intake is likely to affect long-term health. High concentrations are found in some rice-based foods and drinks widely used in infants and young children. In order to reduce exposure we recommend avoidance of rice drinks for infants and young children. For all rice products, strict...... regulation should be enforced regarding arsenic content. Moreover, infants and young children should consume a balanced diet including a variety of grains as carbohydrate sources. While rice protein based infant formulas are an option for infants with cows' milk protein allergy, the inorganic arsenic content...

  9. Inorganic arsenic in drinking water accelerates N-butyl-N-(4-hydroxybutyl)nitrosamine-induced bladder tissue damage in mice

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Paul-Yann [Department of Pathology, Chang Gung Memorial Hospital at Chiayi, Chang Gung University, Chiayi, Taiwan (China); Lin, Yung-Lun; Huang, Chin-Chin; Chen, Sin-Syu [Department of Microbiology, Immunology and Biopharmaceuticals, College of Life Sciences, National Chiayi University, Chiayi, Taiwan (China); Liu, Yi-Wen, E-mail: ywlss@mail.ncyu.edu.tw [Department of Microbiology, Immunology and Biopharmaceuticals, College of Life Sciences, National Chiayi University, Chiayi, Taiwan (China)

    2012-02-15

    Epidemiological studies have revealed that exposure to an arsenic-contaminated environment correlates with the incidence of bladder cancer. Bladder cancer is highly recurrent after intravesical therapy, and most of the deaths from this disease are due to invasive metastasis. In our present study, the role of inorganic arsenic in bladder carcinogenesis is characterized in a mouse model. This work provides the first evidence that inorganic arsenic in drinking water promotes N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced bladder tissue damage, including the urothelium and submucosal layer. This damage to the bladder epithelium induced by BBN includes thickening of the submucosal layer, the loss of the glycosaminoglycan layer and an increase in both the deoxyguanosine oxidation and cytosine methylation levels in the DNA. Further, when 10 ppm inorganic arsenic is combined with BBN, the number of bladder submucosal capillaries is increased. In addition, inorganic arsenic also increases the deoxyguanosine oxidation level, alters the cytosine methylation state, decreases the activities of glutathione reductase and glucose-6-phosphate dehydrogenase, decreases the protein expression of NAD(P)H quinone oxidoreductase-1 (NQO-1) and increases the protein expression of specific protein 1 (Sp1) in bladder tissues. In summary, our data reveal that inorganic arsenic in drinking water promotes the BBN-induced pre-neoplastic damage of bladder tissue in mice, and that the 8-hydroxy-2′-deoxyguanosine, 5-methylcytosine, NQO-1 protein and Sp1 protein levels may be pre-neoplastic markers of bladder tumors. -- Highlights: ► The role of inorganic arsenic in bladder carcinogenesis is characterized in mice. ► We examine the changes in the histology and biochemistry of bladder tissues. ► Inorganic arsenic enhances BBN-induced DNA oxidation while decreases BBN-induced DNA methylation in the mouse bladder. ► Inorganic arsenic alters the activities of the anti-oxidant enzymes in

  10. Mathematical model insights into arsenic detoxification

    Directory of Open Access Journals (Sweden)

    Nijhout H Frederik

    2011-08-01

    Full Text Available Abstract Background Arsenic in drinking water, a major health hazard to millions of people in South and East Asia and in other parts of the world, is ingested primarily as trivalent inorganic arsenic (iAs, which then undergoes hepatic methylation to methylarsonic acid (MMAs and a second methylation to dimethylarsinic acid (DMAs. Although MMAs and DMAs are also known to be toxic, DMAs is more easily excreted in the urine and therefore methylation has generally been considered a detoxification pathway. A collaborative modeling project between epidemiologists, biologists, and mathematicians has the purpose of explaining existing data on methylation in human studies in Bangladesh and also testing, by mathematical modeling, effects of nutritional supplements that could increase As methylation. Methods We develop a whole body mathematical model of arsenic metabolism including arsenic absorption, storage, methylation, and excretion. The parameters for arsenic methylation in the liver were taken from the biochemical literature. The transport parameters between compartments are largely unknown, so we adjust them so that the model accurately predicts the urine excretion rates of time for the iAs, MMAs, and DMAs in single dose experiments on human subjects. Results We test the model by showing that, with no changes in parameters, it predicts accurately the time courses of urinary excretion in mutiple dose experiments conducted on human subjects. Our main purpose is to use the model to study and interpret the data on the effects of folate supplementation on arsenic methylation and excretion in clinical trials in Bangladesh. Folate supplementation of folate-deficient individuals resulted in a 14% decrease in arsenicals in the blood. This is confirmed by the model and the model predicts that arsenicals in the liver will decrease by 19% and arsenicals in other body stores by 26% in these same individuals. In addition, the model predicts that arsenic

  11. Role of soil-derived dissolved substances in arsenic transport and transformation in laboratory experiments.

    Science.gov (United States)

    Chen, Zhangrong; Cai, Yong; Liu, Guangliang; Solo-Gabriele, Helena; Snyder, George H; Cisar, John L

    2008-11-15

    Dissolved substances derived from soil may interact with both soil surfaces and with arsenic and subsequently influence arsenic mobility and species transformation. The purpose of this study was to investigate arsenic transport and transformation in porous media with a specific focus on the impact of soil-derived dissolved substances, mainly consisting of inorganic colloids and dissolved organic matter (DOM), on these processes. Arsenic transport and transformation through columns, which were packed with uncoated sand (UC) or naturally coated sand (NC) and fed with arsenate (AsV) or monomethylarsonic acid (MMA) spiked influents, were investigated in the presence or absence of soil-derived dissolved substances. The presence of soil-derived inorganic colloids and/or DOM clearly enhanced As transport through the column, with the fraction of As leached out of column (referring to the total amount added) being increased from 23 to 46% (UC) and 21 to 50% (NC) in AsV experiments while 46 to 64% (UC) and 28 to 63% (NC) in MMA experiments. The association of arsenic with DOM and the competitive adsorption between arsenic and DOM could account for, at least partly, the enhanced As movement. Distinct species transformation of As during transport through soil columns was observed. When AsV was the initial species spiked in the influent solutions, only arsenite (AsIII) was detected in the effluents for UC columns; while both AsIII (dominant) and AsV were present for NC columns, with AsIII being the dominant species. When MMA was initially spiked in the influent solutions, all method detectable As species, AsIII, AsV, MMA, and dimethylarsenic acid (DMA) were present in the effluents for both soil columns. These results indicate that risk assessment associated with As contamination, particularly due to previous organoarsenical pesticide applications, should take into account the role of soil-derived dissolved substances in promoting As transport and As species transformation.

  12. Role of Soil-derived Dissolved Substances in Arsenic Transport and Transformation in Laboratory Experiments

    Science.gov (United States)

    Chen, Zhangrong; Cai, Yong; Liu, Guangliang; Solo-Gabriele, Helena; Snyder, George H.; Cisar, John L.

    2011-01-01

    Dissolved substances derived from soil may interact with both soil surfaces and with arsenic and subsequently influence arsenic mobility and species transformation. The purpose of this study was to investigate arsenic transport and transformation in porous media with a specific focus on the impact of soil-derived dissolved substances, mainly consisting of inorganic colloids and dissolved organic matter (DOM), on these processes. Arsenic transport and transformation through columns, which were packed with uncoated sand (UC) or naturally coated sand (NC) and fed with arsenate (AsV) or monomethylarsonic acid (MMA) spiked influents, were investigated in the presence or absence of soil-derived dissolved substances. The presence of soil-derived inorganic colloids and/or DOM clearly enhanced As transport through the column, with the fraction of As leached out of column (referring to the total amount added) being increased from 23 to 46% (UC) and 21 to 50% (NC) in AsV experiments while 46 to 64% (UC) and 28 to 63% (NC) in MMA experiments. The association of arsenic with DOM and the competitive adsorption between arsenic and DOM could account for, at least partly, the enhanced As movement. Distinct species transformation of As during transport through soil columns was observed. When AsV was the initial species spiked in the influent solutions, only arsenite (AsIII) was detected in the effluents for UC columns; while both AsIII (dominant) and AsV were present for NC columns, with AsIII being the dominant species. When MMA was initially spiked in the influent solutions, all method detectable As species, AsIII, AsV, MMA, and dimethylarsenic acid (DMA) were present in the effluents for both soil columns. These results indicate that risk assessment associated with As contamination, particularly due to previous organoarsenical pesticide applications, should take into account the role of soil-derived dissolved substances in promoting As transport and As species transformation

  13. Global Fitness Profiling Identifies Arsenic and Cadmium Tolerance Mechanisms in Fission Yeast

    Science.gov (United States)

    Guo, Lan; Ganguly, Abantika; Sun, Lingling; Suo, Fang; Du, Li-Lin; Russell, Paul

    2016-01-01

    Heavy metals and metalloids such as cadmium [Cd(II)] and arsenic [As(III)] are widespread environmental toxicants responsible for multiple adverse health effects in humans. However, the molecular mechanisms underlying metal-induced cytotoxicity and carcinogenesis, as well as the detoxification and tolerance pathways, are incompletely understood. Here, we use global fitness profiling by barcode sequencing to quantitatively survey the Schizosaccharomyces pombe haploid deletome for genes that confer tolerance of cadmium or arsenic. We identified 106 genes required for cadmium resistance and 110 genes required for arsenic resistance, with a highly significant overlap of 36 genes. A subset of these 36 genes account for almost all proteins required for incorporating sulfur into the cysteine-rich glutathione and phytochelatin peptides that chelate cadmium and arsenic. A requirement for Mms19 is explained by its role in directing iron–sulfur cluster assembly into sulfite reductase as opposed to promoting DNA repair, as DNA damage response genes were not enriched among those required for cadmium or arsenic tolerance. Ubiquinone, siroheme, and pyridoxal 5′-phosphate biosynthesis were also identified as critical for Cd/As tolerance. Arsenic-specific pathways included prefoldin-mediated assembly of unfolded proteins and protein targeting to the peroxisome, whereas cadmium-specific pathways included plasma membrane and vacuolar transporters, as well as Spt–Ada–Gcn5-acetyltransferase (SAGA) transcriptional coactivator that controls expression of key genes required for cadmium tolerance. Notable differences are apparent with corresponding screens in the budding yeast Saccharomyces cerevisiae, underscoring the utility of analyzing toxic metal defense mechanisms in both organisms. PMID:27558664

  14. Global Fitness Profiling Identifies Arsenic and Cadmium Tolerance Mechanisms in Fission Yeast

    Directory of Open Access Journals (Sweden)

    Lan Guo

    2016-10-01

    Full Text Available Heavy metals and metalloids such as cadmium [Cd(II] and arsenic [As(III] are widespread environmental toxicants responsible for multiple adverse health effects in humans. However, the molecular mechanisms underlying metal-induced cytotoxicity and carcinogenesis, as well as the detoxification and tolerance pathways, are incompletely understood. Here, we use global fitness profiling by barcode sequencing to quantitatively survey the Schizosaccharomyces pombe haploid deletome for genes that confer tolerance of cadmium or arsenic. We identified 106 genes required for cadmium resistance and 110 genes required for arsenic resistance, with a highly significant overlap of 36 genes. A subset of these 36 genes account for almost all proteins required for incorporating sulfur into the cysteine-rich glutathione and phytochelatin peptides that chelate cadmium and arsenic. A requirement for Mms19 is explained by its role in directing iron–sulfur cluster assembly into sulfite reductase as opposed to promoting DNA repair, as DNA damage response genes were not enriched among those required for cadmium or arsenic tolerance. Ubiquinone, siroheme, and pyridoxal 5′-phosphate biosynthesis were also identified as critical for Cd/As tolerance. Arsenic-specific pathways included prefoldin-mediated assembly of unfolded proteins and protein targeting to the peroxisome, whereas cadmium-specific pathways included plasma membrane and vacuolar transporters, as well as Spt–Ada–Gcn5-acetyltransferase (SAGA transcriptional coactivator that controls expression of key genes required for cadmium tolerance. Notable differences are apparent with corresponding screens in the budding yeast Saccharomyces cerevisiae, underscoring the utility of analyzing toxic metal defense mechanisms in both organisms.

  15. Ana insect model for assessing arsenic toxicity: Arsenic elevated glutathione content in the musca domestica and trichoplusia ni

    Energy Technology Data Exchange (ETDEWEB)

    Zaman, K.; Pardini, R.S. [Univ. of Nevada, Reno, NV (United States)

    1995-12-01

    Throughout history, arsenic has acquired an unparalled reputation as a poison. Arsenic was used as a poison as early as 2000 B.C. The toxicity of arsenic (As) extends to mammals, fish, insects, plants and fungi. According to epidemiological evidence, inorganic arsenic compounds have been strongly suggested as human carcinogens. Human exposure to arsenic through various means is correlated with an increased incidence of skin, lung, and possibly liver cancers. Inorganic trivalent arsenic is systematically more poisonous than the pentavalent form and it is possible that pentavalent arsenic is reduced to the trivalent form before exerting any toxic effects. This study focuses on the potential to use two insect species, the housefly, Musca domestica and the cabbage looper moth, Trichoplusia ni, and a model for the study of arsenic toxicity. After 48 hours of exposure to Arsenic, a significant induction of Glutathione level and subsequent decrease in the level of GSSG in both species were observed. 21 refs., 2 figs., 1 tab.

  16. Arsenic poisoning of cattle and other domestic animals

    Energy Technology Data Exchange (ETDEWEB)

    Moxham, J.W.; Coup, M.R.

    1968-01-01

    One hundred and sixty-one incidents of arsenic poisoning in domestic animals were recorded at Ruakura Veterinary Diagnostic Station from 1955 to 1967. Cattle was the animal species most subject to arsenic poisoning. Clincal signs, post-mortem findings and sources of arsenic are given. Arsenic poisoning was more prevalent in younger cattle and during the warmer months of the year. With cattle most incidents were associated with carelessly discarded arsenical compounds, although most deaths occurred when these compounds were deliberately used. In other species, losses were generally caused by the deliberate use of arsenical preparations for dipping, drenching and weed spraying. 10 references, 2 tables.

  17. Significantly increased risk of carotid atherosclerosis with arsenic exposure and polymorphisms in arsenic metabolism genes

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Yi-Chen [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Lien, Li-Ming [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); School of Medicine, Taipei Medical University, Taipei, Taiwan (China); Department of Neurology, Shin Kong WHS Memorial Hospital, Taipei, Taiwan (China); Chung, Wen-Ting [Department of Neurology, Wanfang Hospital, Taipei Medical University, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan (China); Hsieh, Fang-I; Hsieh, Pei-Fan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Wu, Meei-Maan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Graduate Institute of Basic Medicine, College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan (China); Tseng, Hung-Pin [Department of Neurology, Lotung Poh-Ai Hospital, I-Lan, Taiwan (China); Chiou, Hung-Yi, E-mail: hychiou@tmu.edu.tw [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Chen, Chien-Jen [Genomics Research Center, Academia Sinica, Taipei, Taiwan (China)

    2011-08-15

    Individual susceptibility to arsenic-induced carotid atherosclerosis might be associated with genetic variations in arsenic metabolism. The purpose of this study is to explore the interaction effect on risk of carotid atherosclerosis between arsenic exposure and risk genotypes of purine nucleoside phosphorylase (PNP), arsenic (+3) methyltransferase (As3MT), and glutathione S-transferase omega 1 (GSTO1) and omega 2 (GSTO2). A community-based case-control study was conducted in northeastern Taiwan to investigate the arsenic metabolic-related genetic susceptibility to carotid atherosclerosis. In total, 863 subjects, who had been genotyped and for whom the severity of carotid atherosclerosis had been determined, were included in the present study. Individual well water was collected and arsenic concentration determined using hydride generation combined with flame atomic absorption spectrometry. The result showed that a significant dose-response trend (P=0.04) of carotid atherosclerosis risk associated with increasing arsenic concentration. Non-significant association between genetic polymorphisms of PNP Gly51Ser, Pro57Pro, As3MT Met287Thr, GSTO1 Ala140Asp, and GSTO2 A-183G and the risk for development of carotid atherosclerosis were observed. However, the significant interaction effect on carotid atherosclerosis risk was found for arsenic exposure (>50 {mu}g/l) and the haplotypes of PNP (p=0.0115). A marked elevated risk of carotid atherosclerosis was observed in subjects with arsenic exposure of >50 {mu}g/l in drinking water and those who carried the PNP A-T haplotype and at least either of the As3MT risk polymorphism or GSTO risk haplotypes (OR, 6.43; 95% CI, 1.79-23.19). In conclusion, arsenic metabolic genes, PNP, As3MT, and GSTO, may exacerbate the formation of atherosclerosis in individuals with high levels of arsenic concentration in well water (>50 {mu}g/l). - Highlights: {yields}Arsenic metabolic genes might be associated with carotid atherosclerosis. {yields

  18. MDI Biological Laboratory Arsenic Summit: Approaches to Limiting Human Exposure to Arsenic.

    Science.gov (United States)

    Stanton, Bruce A; Caldwell, Kathleen; Congdon, Clare Bates; Disney, Jane; Donahue, Maria; Ferguson, Elizabeth; Flemings, Elsie; Golden, Meredith; Guerinot, Mary Lou; Highman, Jay; James, Karen; Kim, Carol; Lantz, R Clark; Marvinney, Robert G; Mayer, Greg; Miller, David; Navas-Acien, Ana; Nordstrom, D Kirk; Postema, Sonia; Rardin, Laurie; Rosen, Barry; SenGupta, Arup; Shaw, Joseph; Stanton, Elizabeth; Susca, Paul

    2015-09-01

    This report is the outcome of the meeting "Environmental and Human Health Consequences of Arsenic" held at the MDI Biological Laboratory in Salisbury Cove, Maine, August 13-15, 2014. Human exposure to arsenic represents a significant health problem worldwide that requires immediate attention according to the World Health Organization (WHO). One billion people are exposed to arsenic in food, and more than 200 million people ingest arsenic via drinking water at concentrations greater than international standards. Although the US Environmental Protection Agency (EPA) has set a limit of 10 μg/L in public water supplies and the WHO has recommended an upper limit of 10 μg/L, recent studies indicate that these limits are not protective enough. In addition, there are currently few standards for arsenic in food. Those who participated in the Summit support citizens, scientists, policymakers, industry, and educators at the local, state, national, and international levels to (1) establish science-based evidence for setting standards at the local, state, national, and global levels for arsenic in water and food; (2) work with government agencies to set regulations for arsenic in water and food, to establish and strengthen non-regulatory programs, and to strengthen collaboration among government agencies, NGOs, academia, the private sector, industry, and others; (3) develop novel and cost-effective technologies for identification and reduction of exposure to arsenic in water; (4) develop novel and cost-effective approaches to reduce arsenic exposure in juice, rice, and other relevant foods; and (5) develop an Arsenic Education Plan to guide the development of science curricula as well as community outreach and education programs that serve to inform students and consumers about arsenic exposure and engage them in well water testing and development of remediation strategies.

  19. Arsenic exposure from drinking water, arsenic methylation capacity, and carotid intima-media thickness in Bangladesh.

    Science.gov (United States)

    Chen, Yu; Wu, Fen; Graziano, Joseph H; Parvez, Faruque; Liu, Mengling; Paul, Rina Rani; Shaheen, Ishrat; Sarwar, Golam; Ahmed, Alauddin; Islam, Tariqul; Slavkovich, Vesna; Rundek, Tatjana; Demmer, Ryan T; Desvarieux, Moise; Ahsan, Habibul

    2013-08-01

    We conducted a cross-sectional study to evaluate the interrelationships between past arsenic exposure, biomarkers specific for susceptibility to arsenic exposure, and carotid intima-media thickness (cIMT) in 959 subjects from the Health Effects of Arsenic Longitudinal Study in Bangladesh. We measured cIMT levels on average 7.2 years after baseline during 2010-2011. Arsenic exposure was measured in well water at baseline and in urine samples collected at baseline and during follow-up. Every 1-standard-deviation increase in urinary arsenic (357.9 µg/g creatinine) and well-water arsenic (102.0 µg/L) concentration was related to a 11.7-µm (95% confidence interval (CI): 1.8, 21.6) and 5.1-µm (95% CI: -0.2, 10.3) increase in cIMT, respectively. For every 10% increase in monomethylarsonic acid (MMA) percentage, there was an increase of 12.1 µm (95% CI: 0.4, 23.8) in cIMT. Among participants with a higher urinary MMA percentage, a higher ratio of urinary MMA to inorganic arsenic, and a lower ratio of dimethylarsinic acid to MMA, the association between well-water arsenic and cIMT was stronger. The findings indicate an effect of past long-term arsenic exposure on cIMT, which may be potentiated by suboptimal or incomplete arsenic methylation capacity. Future prospective studies are needed to confirm the association between arsenic methylation capacity and atherosclerosis-related outcomes.

  20. Arsenic stress after the Proterozoic glaciations

    Science.gov (United States)

    Chi Fru, Ernest; Arvestål, Emma; Callac, Nolwenn; El Albani, Abderrazak; Kilias, Stephanos; Argyraki, Ariadne; Jakobsson, Martin

    2015-12-01

    Protection against arsenic damage in organisms positioned deep in the tree of life points to early evolutionary sensitization. Here, marine sedimentary records reveal a Proterozoic arsenic concentration patterned to glacial-interglacial ages. The low glacial and high interglacial sedimentary arsenic concentrations, suggest deteriorating habitable marine conditions may have coincided with atmospheric oxygen decline after ~2.1 billion years ago. A similar intensification of near continental margin sedimentary arsenic levels after the Cryogenian glaciations is also associated with amplified continental weathering. However, interpreted atmospheric oxygen increase at this time, suggests that the marine biosphere had widely adapted to the reorganization of global marine elemental cycles by glaciations. Such a glacially induced biogeochemical bridge would have produced physiologically robust communities that enabled increased oxygenation of the ocean-atmosphere system and the radiation of the complex Ediacaran-Cambrian life.

  1. Arsenic binding to Fucus vesiculosus metallothionein.

    Science.gov (United States)

    Merrifield, Maureen E; Ngu, Thanh; Stillman, Martin J

    2004-11-05

    The seaweed Fucus vesiculosus is a member of the brown algae family. Kille and co-workers [Biochem. J. 338 (1999) 553] reported that this species contains the gene for metallothionein. Metallothionein is a metalloprotein having low molecular weight, and high cysteine content, which binds a range of metals. F. vesiculosus bioaccumulates arsenic from the aquatic environment [Mar. Chem. 18 (1986) 321]. In this paper we describe arsenic binding to F. vesiculosus metallothionein, characterized by electrospray ionization mass spectrometry. Five arsenic-MT species were detected with increasing As to protein ratios. These results provide important information about the metal-chelation behaviour of this novel algal metallothionein which is a putative model for arsenic binding to F. vesiculosus in vivo.

  2. Arsenic stress after the Proterozoic glaciations.

    Science.gov (United States)

    Fru, Ernest Chi; Arvestål, Emma; Callac, Nolwenn; El Albani, Abderrazak; Kilias, Stephanos; Argyraki, Ariadne; Jakobsson, Martin

    2015-12-04

    Protection against arsenic damage in organisms positioned deep in the tree of life points to early evolutionary sensitization. Here, marine sedimentary records reveal a Proterozoic arsenic concentration patterned to glacial-interglacial ages. The low glacial and high interglacial sedimentary arsenic concentrations, suggest deteriorating habitable marine conditions may have coincided with atmospheric oxygen decline after ~2.1 billion years ago. A similar intensification of near continental margin sedimentary arsenic levels after the Cryogenian glaciations is also associated with amplified continental weathering. However, interpreted atmospheric oxygen increase at this time, suggests that the marine biosphere had widely adapted to the reorganization of global marine elemental cycles by glaciations. Such a glacially induced biogeochemical bridge would have produced physiologically robust communities that enabled increased oxygenation of the ocean-atmosphere system and the radiation of the complex Ediacaran-Cambrian life.

  3. Rapid thermal anneal of arsenic implanted silicon

    Energy Technology Data Exchange (ETDEWEB)

    Feygenson, A.

    1985-01-01

    The distribution of arsenic implanted into silicon during rapid thermal anneal (RTA) was investigated. Secondary ion mass spectrometry, Rutherford backscattering spectrometry, and channeling techniques were used for the measurement of the total (chemical) dopant profile. The electrically active dopant profiles were measured with sheet resistance, sheet-resistance maps, spreading resistance and pinch resistors. It was found that arsenic profile after RTA is influenced by many parameters including crystallographic orientation of the sample, temperature gradient, and defect structure in the surface part affected by heavy arsenic implant. A diffusion model based on inhomogeneous medium was examined. Exact solutions of the diffusion equation were obtained for the rectangular and Gaussian initial dopant profiles. Calculated results are compared to the measured profiles. It is concluded that model satisfactory predicts the major features of the arsenic diffusion into silicon during RTA.

  4. Rapid Thermal Anneal of Arsenic Implanted Silicon.

    Science.gov (United States)

    Feygenson, Anatoly

    1985-12-01

    The distribution of arsenic implanted into silicon during rapid thermal anneal (RTA) has been investigated. Secondary ion mass spectrometry (SIMS), Rutherford backscattering spectrometry (RBS) and channeling techniques were used for the measurement of the total (chemical) dopant profile. The electrically active dopant profiles were measured with sheet resistance, sheet resistance maps, spreading resistance, and pinch resistors. It has been found that arsenic profile after RTA is influenced by many parameters including crystallographic orientation of the sample, temperature gradient, and defect structure in the surface part affected by heavy arsenic implant. A diffusion model based on inhomogeneous medium was examined. Exact solutions of the diffusion equation were obtained for the rectangular and Gaussian initial dopant profiles. Calculated results are compared to the measured profiles. It is concluded that model satisfactory predicts the major features of the arsenic diffusion into silicon during RTA.

  5. ArsH is an organoarsenical oxidase that confers resistance to trivalent forms of the herbicide MSMA and the poultry growth promoter roxarsone

    OpenAIRE

    2015-01-01

    Environmental organoarsenicals are produced by microorganisms and are introduced anthropogenically as herbicides and antimicrobial growth promoters for poultry and swine. Nearly every prokaryote has an ars (arsenic resistance) operon, and some have an arsH gene encoding an atypical flavodoxin. The role of ArsH in arsenic resistance has been unclear. Here we demonstrate that ArsH is an organoarsenical oxidase that detoxifies trivalent methylated and aromatic arsenicals by oxidation to pentaval...

  6. Polymorphism of inflammatory genes and arsenic methylation capacity are associated with urothelial carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chia-Chang [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Department of Urology, Taipei Medical University—Shuang Ho Hospital, Taipei, Taiwan (China); Huang, Yung-Kai [School of Oral Hygiene, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan (China); Chung, Chi-Jung [Department of Health Risk Management, College of Public Health, China Medical University and Hospital, Taichung, Taiwan (China); Department of Medical Research, China Medical University Hospital, Taichung, Taiwan (China); Huang, Chao-Yuan; Pu, Yeong-Shiau [Department of Urology, National Taiwan University Hospital, College of Medicine National Taiwan University, Taipei, Taiwan (China); Shiue, Horng-Sheng [Department of Chinese Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan (China); Lai, Li-An [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Lin, Ying-Chin [Department of Family Medicine, Shung Ho Hospital, Taipei Medical University, Taipei, Taiwan (China); Department of Health Examination, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan (China); Su, Chien-Tien [Department of Family Medicine, Taipei Medical University Hospital, Taipei, Taiwan (China); Hsueh, Yu-Mei, E-mail: ymhsueh@tmu.edu.tw [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China)

    2013-10-01

    Chronic exposure to arsenic can generate reactive oxidative species, which can induce certain proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-8 (IL-8). TNF-α, IL-6 and IL-8 have been shown to be involved in the development and progression of various cancers, including bladder cancer. This study aimed to investigate the joint effect of the polymorphism of TNF-α − 308 G/A, IL-6 − 174 G/C, IL-8 − 251 T/A and urinary arsenic profiles on urothelial carcinoma (UC) risk. This study evaluated 300 pathologically-confirmed cases of UC and 594 cancer-free controls. Urinary arsenic species were detected using high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. The polymorphism of TNF-α − 308 G/A, IL-6 − 174 G/C and IL-8 − 251 T/A was determined using polymerase chain reaction-restriction fragment length polymorphism. The joint effects on UC risk were estimated by odds ratios and 95% confidence intervals using unconditional logistic regression. We found that the TNF-α − 308 A/A and IL-8 − 251 T/T polymorphisms were significantly associated with UC. Moreover, significant dose–response joint effect of TNF-α − 308 A/A or IL-8 − 251 T/T genotypes and arsenic methylation indices were seen to affect UC risk. The present results also showed a significant increase in UC risk in subjects with the IL-8 − 251 T/T genotype for each SD increase in urinary total arsenic and MMA%. In contrast, a significant decrease in UC risk was found in subjects who carried the IL-8 − 251 T/T genotype for each SD increase in DMA%. - Highlights: • Joint effect of the TNF-α -308 A/A genotype and urinary total arsenic affected UC. • Joint effect of the IL-8 -251 T/T genotype and urinary total arsenic affected UC. • Urinary total arsenic level, TNF-α -308 A/A and IL-8 -251 T/T genotype affected UC.

  7. Arsenic: Not So Evil After All?

    Science.gov (United States)

    Lykknes, Annette; Kvittingen, Lise

    2003-05-01

    This article presents parts of the history of the element arsenic in order to illustrate processes behind development of knowledge in chemistry. The particular aspects presented here are the use of arsenic as a stimulant by Styrian peasants, in Fowler's solution, in drugs of the 19th century (e.g., salvarsan), and in current medical treatment, all of which challenge the myth of this element as exclusively poisonous.

  8. Biosensors for Inorganic and Organic Arsenicals

    Science.gov (United States)

    Chen, Jian; Rosen, Barry P.

    2014-01-01

    Arsenic is a natural environmental contaminant to which humans are routinely exposed and is strongly associated with human health problems, including cancer, cardiovascular and neurological diseases. To date, a number of biosensors for the detection of arsenic involving the coupling of biological engineering and electrochemical techniques has been developed. The properties of whole-cell bacterial or cell-free biosensors are summarized in the present review with emphasis on their sensitivity and selectivity. Their limitations and future challenges are highlighted. PMID:25587436

  9. 55th electric science promotion prize (progress prize). Demonstration of optical soliton transmission on OPGW first in the world; Dai 55 kai denki gakujutsu shinkosho (shinposho) jusho. Seiaihatsu no OPGW ni okeru hikari soriton denso no jissho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-10

    Electric science promotion prize (progress prize) is given to `Person who newly proposed a new concept, theory, material, device, system and method on electrical science and technology, or demonstrated these proposals` by the commendation committee of Institute of Electrical Engineers of Japan every year. Eight promotion prizes including that for Kansai Electric Power`s `Demonstration of optical soliton transmission on OPGW first in the world` were given. This research succeeded in development of the transmission/ receiving device suitable for optical soliton transmission, and the prediction method of an optimum transmission condition by computer simulation. In addition, this research succeeded in 10Gbit transmission of 784km and 40Gbit transmission (4-wave multiplex) of 392km by applying the above research result to Okurobe trunk line OPGW (98.2km). This demonstration of optical soliton transmission on OPGW is first in the world. (NEDO)

  10. Clarify Industry Development,Enhance Fundamental Research, Promote Material Progress and Push Industrial Upgrade%厘清行业发展加强基础研究促进技术进步推动产业升级

    Institute of Scientific and Technical Information of China (English)

    董书山; 陶强; 乔翠娅

    2016-01-01

    文章简要分析了超硬制品的国内外市场竞争、产业结构、产品发展及技术现状。提出了推动材料进步,加强基础研究,转变设计理念,带动工艺装备发展,促进行业的创新发展与升级转型的发展观念。%The competition in domestic and world market,industrial structure,product de-velopment and technical state of superhard product have been briefly analyzed in this arti-cle.Besides,the development concept of promoting material progress,enhancing funda-mental research,transforming design philosophy,encouraging technological equipment development,promoting innovative development,upgrading and transformation of the in-dustry have been put forward.

  11. Arsenic speciation patterns in freshwater fish.

    Science.gov (United States)

    Slejkovec, Zdenka; Bajc, Zlatka; Doganoc, Darinka Z

    2004-04-19

    Muscle of 16 freshwater fish (9 different species belonging to 4 different families) was analysed for arsenic species using HPLC separation (anion and cation exchange) followed by on-line UV-decomposition, hydride generation and AFS detection. The main arsenic compounds found in the extracts were arsenobetaine (AsB), which accounted for 92-100% of extractable arsenic in species of salmonids (Salmo marmoratus, Oncorhynchus mykiss, Salmo trutta m. fario), and dimethylarsinic acid (DMAA), which accounted for 75% of extractable arsenic in burbot (Lota lota). AsB was also found in lower concentrations in almost all other fish species analysed (Silurus glanis, L. lota, Barbus barbus, Rutilus pigus virgo, Chondrostoma nasus). Arsenite (As(III)) and trimethylarsine oxide (TMAO) were detected in low concentrations in some representatives of Cyprinidae only (R. pigus virgo, C. nasus). Except in salmonids, an unknown cationic compound was present in most of the samples in relatively low concentrations. Cluster analysis of the generated data seems to indicate that there is a correlation between fish family and the arsenic speciation pattern. This is especially clear for the salmonids which show a completely separate cluster and thus a very distinct arsenic speciation pattern.

  12. Earthworms produce phytochelatins in response to arsenic.

    Directory of Open Access Journals (Sweden)

    Manuel Liebeke

    Full Text Available Phytochelatins are small cysteine-rich non-ribosomal peptides that chelate soft metal and metalloid ions, such as cadmium and arsenic. They are widely produced by plants and microbes; phytochelatin synthase genes are also present in animal species from several different phyla, but there is still little known about whether these genes are functional in animals, and if so, whether they are metal-responsive. We analysed phytochelatin production by direct chemical analysis in Lumbricus rubellus earthworms exposed to arsenic for a 28 day period, and found that arsenic clearly induced phytochelatin production in a dose-dependent manner. It was necessary to measure the phytochelatin metabolite concentrations directly, as there was no upregulation of phytochelatin synthase gene expression after 28 days: phytochelatin synthesis appears not to be transcriptionally regulated in animals. A further untargetted metabolomic analysis also found changes in metabolites associated with the transsulfuration pathway, which channels sulfur flux from methionine for phytochelatin synthesis. There was no evidence of biological transformation of arsenic (e.g. into methylated species as a result of laboratory arsenic exposure. Finally, we compared wild populations of earthworms sampled from the field, and found that both arsenic-contaminated and cadmium-contaminated mine site worms had elevated phytochelatin concentrations.

  13. Earthworms produce phytochelatins in response to arsenic.

    Science.gov (United States)

    Liebeke, Manuel; Garcia-Perez, Isabel; Anderson, Craig J; Lawlor, Alan J; Bennett, Mark H; Morris, Ceri A; Kille, Peter; Svendsen, Claus; Spurgeon, David J; Bundy, Jacob G

    2013-01-01

    Phytochelatins are small cysteine-rich non-ribosomal peptides that chelate soft metal and metalloid ions, such as cadmium and arsenic. They are widely produced by plants and microbes; phytochelatin synthase genes are also present in animal species from several different phyla, but there is still little known about whether these genes are functional in animals, and if so, whether they are metal-responsive. We analysed phytochelatin production by direct chemical analysis in Lumbricus rubellus earthworms exposed to arsenic for a 28 day period, and found that arsenic clearly induced phytochelatin production in a dose-dependent manner. It was necessary to measure the phytochelatin metabolite concentrations directly, as there was no upregulation of phytochelatin synthase gene expression after 28 days: phytochelatin synthesis appears not to be transcriptionally regulated in animals. A further untargetted metabolomic analysis also found changes in metabolites associated with the transsulfuration pathway, which channels sulfur flux from methionine for phytochelatin synthesis. There was no evidence of biological transformation of arsenic (e.g. into methylated species) as a result of laboratory arsenic exposure. Finally, we compared wild populations of earthworms sampled from the field, and found that both arsenic-contaminated and cadmium-contaminated mine site worms had elevated phytochelatin concentrations.

  14. A novel arsenic methyltransferase gene of Westerdykella aurantiaca isolated from arsenic contaminated soil: phylogenetic, physiological, and biochemical studies and its role in arsenic bioremediation.

    Science.gov (United States)

    Verma, Shikha; Verma, Pankaj Kumar; Meher, Alok Kumar; Dwivedi, Sanjay; Bansiwal, Amit Kumar; Pande, Veena; Srivastava, Pankaj Kumar; Verma, Praveen Chandra; Tripathi, Rudra Deo; Chakrabarty, Debasis

    2016-03-01

    Elevated arsenic concentration in the environment and agricultural soil is a serious concern to crop production and human health. Among different detoxification mechanisms, the methylation of arsenic is a widespread phenomenon in nature. A number of microorganisms are able to methylate arsenic, but less is known about the arsenic metabolism in fungi. We identified a novel arsenic methyltransferase (WaarsM) gene from a soil fungus, Westerdykella aurantiaca. WaarsM showed sequence homology with all known arsenic methyltransferases having three conserved SAM binding motifs. The expression of WaarsM enhanced arsenic resistance in E. coli (Δars) and S. cerevisiae (Δacr2) strains by biomethylation and required endogenous reductants, preferably GSH, for methyltransferase activity. The purified WaarsM catalyzes the production of methylated arsenicals from both AsIII and AsV, and also displays AsV reductase activity. It displayed higher methyltransferase activity and lower KM 0.1945 ± 0.021 mM and KM 0.4034 ± 0.078 mM for AsIII and AsV, respectively. S. cerevisiae (Δacr2) cells expressing WaarsM produced 2.2 ppm volatile arsenic and 0.64 ppm DMA(v) with 0.58 ppm volatile arsenicals when exposed to 20 ppm AsV and 2 ppm AsIII, respectively. Arsenic tolerance in rice after co-culture with genetically engineered yeast suggested its potential role in arsenic bioremediation. Thus, characterization of WaarsM provides a potential strategy to reduce arsenic concentration in soil with reduced arsenic accumulation in crops grown in arsenic contaminated areas, and thereby alleviating human health risks.

  15. Effects of arsenic on nitrogen metabolism in arsenic hyperaccumulator and non-hyperaccumulator ferns

    Science.gov (United States)

    This study investigated the effects of arsenic on the in vitro activities of the enzymes (nitrate reductase and nitrite reductase) involved in nitrate metabolism in the roots, rhizomes, and fronds of two four-month old fern plants, Pteris vittata, an arsenic-hyperaccumulator, and Pteris ensiformis, ...

  16. Microbial transformations of arsenic: perspectives for biological removal of arsenic from water

    NARCIS (Netherlands)

    Cavalca, L.; Corsini, A.; Zaccheo, P.; Andreoni, V.; Muyzer, G.

    2013-01-01

    Arsenic is present in many environments and is released by various natural processes and anthropogenic actions. Although arsenic is recognized to cause a wide range of adverse health effects in humans, diverse bacteria can metabolize it by detoxification and energy conservation reactions. This revie

  17. Evidence against the nuclear in situ binding of arsenicals-oxidative stress theory of arsenic carcinogenesis

    Science.gov (United States)

    A large amount of evidence suggests that arsenicals act via oxidative stress in causing cancer in humans and experimental animals. It is possible that arsenicals could bind in situ close to nuclear DNA followed by Haber-Weiss type oxidative DNA damage. Therefore, we tested this...

  18. Role of complex organic arsenicals in food in aggregate exposure to arsenic

    Science.gov (United States)

    For much of the world’s population, food is the major source of exposure to arsenic. Exposure to this non-essential metalloid at relatively low levels has been linked to a wide range of adverse health effects. Thus, evaluating foods as sources of exposure to arsenic is impo...

  19. Total Arsenic, Cadmium, and Lead Determination in Brazilian Rice Samples Using ICP-MS

    Science.gov (United States)

    Buzzo, Márcia Liane; de Arauz, Luciana Juncioni; Carvalho, Maria de Fátima Henriques; Arakaki, Edna Emy Kumagai; Matsuzaki, Richard; Tiglea, Paulo

    2016-01-01

    This study is aimed at investigating a suitable method for rice sample preparation as well as validating and applying the method for monitoring the concentration of total arsenic, cadmium, and lead in rice by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Various rice sample preparation procedures were evaluated. The analytical method was validated by measuring several parameters including limit of detection (LOD), limit of quantification (LOQ), linearity, relative bias, and repeatability. Regarding the sample preparation, recoveries of spiked samples were within the acceptable range from 89.3 to 98.2% for muffle furnace, 94.2 to 103.3% for heating block, 81.0 to 115.0% for hot plate, and 92.8 to 108.2% for microwave. Validation parameters showed that the method fits for its purpose, being the total arsenic, cadmium, and lead within the Brazilian Legislation limits. The method was applied for analyzing 37 rice samples (including polished, brown, and parboiled), consumed by the Brazilian population. The total arsenic, cadmium, and lead contents were lower than the established legislative values, except for total arsenic in one brown rice sample. This study indicated the need to establish monitoring programs for emphasizing the study on this type of cereal, aiming at promoting the Public Health.

  20. Total Arsenic, Cadmium, and Lead Determination in Brazilian Rice Samples Using ICP-MS

    Directory of Open Access Journals (Sweden)

    Lidiane Raquel Verola Mataveli

    2016-01-01

    Full Text Available This study is aimed at investigating a suitable method for rice sample preparation as well as validating and applying the method for monitoring the concentration of total arsenic, cadmium, and lead in rice by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS. Various rice sample preparation procedures were evaluated. The analytical method was validated by measuring several parameters including limit of detection (LOD, limit of quantification (LOQ, linearity, relative bias, and repeatability. Regarding the sample preparation, recoveries of spiked samples were within the acceptable range from 89.3 to 98.2% for muffle furnace, 94.2 to 103.3% for heating block, 81.0 to 115.0% for hot plate, and 92.8 to 108.2% for microwave. Validation parameters showed that the method fits for its purpose, being the total arsenic, cadmium, and lead within the Brazilian Legislation limits. The method was applied for analyzing 37 rice samples (including polished, brown, and parboiled, consumed by the Brazilian population. The total arsenic, cadmium, and lead contents were lower than the established legislative values, except for total arsenic in one brown rice sample. This study indicated the need to establish monitoring programs for emphasizing the study on this type of cereal, aiming at promoting the Public Health.

  1. Gene Analysis of Arsenic Trioxide—induced Apoptosis of Lymphoma Cells

    Institute of Scientific and Technical Information of China (English)

    ZHANGZidong; LIWeiyu; 等

    2002-01-01

    Objective The effect of arsenic trioxide on apoptosis gene expression of Raji cell was explored when Raji cells were incubated with 0.5μmol/L of arsenic trioxide for 6h。Methods Cell culture,extraction and isolation of mRNA,preparation of probes labeled with fluorescence,hybridization technique of DNA chip(each chip containing 200 apoptosis genes,Chinese Shanghai Biostar,In.)were used.Results Arsenic trioxide induced significant changes in 10%(20/200 genes)of the apoptosis genes:18 genes were downregulated,only two upregulated.In particular,inhibitors of apoptosis protein,such as X-linked inhibitor of apoptosis protein,were significantly downregulated.P53 and the other apoptosis genes were also downregulatec.Of the upregulated genes,high expression of heat-shock protein could promote apoptosis of Raji cells.Conclusion The inhibitors of apoptosis protein play an important role in the process of arsenic trioxide-induced apoptosis of Raji cells.

  2. Exposure to inorganic arsenic in soil increases urinary inorganic arsenic concentrations of residents living in old mining areas.

    Science.gov (United States)

    Hinwood, Andrea L; Sim, Malcolm R; Jolley, Damien; de Klerk, Nick; Bastone, Elisa B; Gerostamoulos, Jim; Drummer, Olaf H

    2004-03-01

    The short term human exposure studies conducted on populations exposed to high concentrations of inorganic arsenic in soil have been inconsistent in demonstrating a relationship between environmental concentrations and exposure measures. In Australia there are many areas with very high arsenic concentrations in residential soil most typically associated with gold mining activities in rural areas. This study aimed to investigate the relationship between environmental arsenic and urinary inorganic arsenic concentrations in a population living in a gold mining area (soil arsenic concentrations between 9 and 9900 mg kg(-1)), and a control population with low arsenic levels in soil (between 1 and 80 mg kg(-1)). Risk factors for increased urinary arsenic concentrations were also explored. There was a weak but significant relationship between soil arsenic concentrations and inorganic urinary arsenic concentration with a Spearman correlation coefficient of 0.39. When participants with greater than 100 mg kg(-1) arsenic in residential soil were selected, the coefficient increased to 0.64. The geometric mean urinary inorganic arsenic concentration for the exposed group was 1.64 microg L(-1) (risk factors. These results show that high concentrations of arsenic in soil can make a contribution to urinary inorganic arsenic concentrations.

  3. Arsenic levels in immigrant children from countries at risk of consuming arsenic polluted water compared to children from Barcelona.

    Science.gov (United States)

    Piñol, S; Sala, A; Guzman, C; Marcos, S; Joya, X; Puig, C; Velasco, M; Velez, D; Vall, O; Garcia-Algar, O

    2015-11-01

    Arsenic is a highly toxic element that pollutes groundwater, being a major environmental problem worldwide, especially in the Bengal Basin. About 40% of patients in our outpatient clinics come from those countries, and there is no published data about their arsenic exposure. This study compares arsenic exposure between immigrant and native children. A total of 114 children (57 natives, 57 immigrants), aged 2 months to 16 years, were recruited and sociodemographic and environmental exposure data were recorded. Total arsenic in urine, hair, and nails and arsenic-speciated compounds in urine were determined. We did not find significant differences in total and inorganic arsenic levels in urine and hair, but in organic arsenic monomethylarsenic acid (MMA) and dimethylarsinous acid (DMA) in urine and in total arsenic in nails. However, these values were not in the toxic range. There were significant differences between longer than 5 years exposure and less than 5 years exposure (consumption of water from tube wells), with respect to inorganic and organic MMA arsenic in urine and total arsenic in nails. There was partial correlation between the duration of exposure and inorganic arsenic levels in urine. Immigrant children have higher arsenic levels than native children, but they are not toxic. At present, there is no need for specific arsenic screening or follow-up in immigrant children recently arrived in Spain from exposure high-risk countries.

  4. Geochemical fate of arsenic in swine litter

    Science.gov (United States)

    Quazi, S.; Makris, K.; Sarkar, D.; Datta, R.; Punamiya, P.

    2007-12-01

    Swine diet is often supplemented by organoarsenicals, such as roxarsone to treat diseases and to promote growth. Recent data reported roxarsone degradation under anaerobic conditions in poultry litter, but no such data exist for swine wastes typically stored in unprotected lagoons in concentrated animal feeding operations (CAFOs). However, serious environmental health risk may arise upon significant arsenic (As) release into solution. The problem may be exacerbated under certain environmental conditions where organoarsenicals, such as roxarsone transform into the more toxic inorganic As, posing serious health risk to the surrounding ecosystem. The objective of this study were to analyze swine wastes collected from 19 randomly selected CAFOs in the USA for As concentrations, and to determine the geochemical fate of As in the swine waste suspensions. Swine wastes were analyzed for total-recoverable, total soluble, and water-extractable As, which were measured by ICP-MS. Speciation of As was performed following a well-established hyphenated technique using HPLC- ICPMS. Swine waste suspensions differed in solids contents; thus, the particulate matters with varying As concentrations were spiked with roxarsone and incubated under dark/light and aerobic/anaerobic conditions. Findings show the prevalence of inorganic As [As(V)] in swine waste suspension solutions. Roxarsone underwent degradation to both organoarsenicals, such as p-ASA, as well as inorganic arsenate and to a number of unidentified metabolites. Roxarsone degradation kinetics was influenced by the solids content and the air conditions (anaerobic/aerobic) of the swine waste suspensions. Maximum degradation rates were observed under anaerobic conditions, in suspensions which were low in solids content. Roxarsone degradation was primarily microbially-mediated, but in certain cases abiotic degradation was also observed, which were significantly slower.

  5. Detection of arsenic ions with preliminary concentrating on magnetic sorbent

    OpenAIRE

    Kharlyamov, Damir; Dvoryak, Stanislav; Mavrin, Gennady

    2013-01-01

    In represented work a method of arsenic ions concentrating is presented by means of sorption with application of synthetic magnetite, which is successfully used for atomic absorption detection of arsenic in natural waters.

  6. Arsenic uptake by Lemna minor in hydroponic system.

    Science.gov (United States)

    Goswami, Chandrima; Majumder, Arunabha; Misra, Amal Kanti; Bandyopadhyay, Kaushik

    2014-01-01

    Arsenic is hazardous and causes several ill effects on human beings. Phytoremediation is the use of aquatic plants for the removal of toxic pollutants from external media. In the present research work, the removal efficiency as well as the arsenic uptake capacity of duckweed Lemna minor has been studied. Arsenic concentration in water samples and plant biomass were determined by AAS. The relative growth factor of Lemna minor was determined. The duckweed had potential to remove as well as uptake arsenic from the aqueous medium. Maximum removal of more than 70% arsenic was achieved atinitial concentration of 0.5 mg/1 arsenic on 15th day of experimental period of 22 days. Removal percentage was found to decrease with the increase in initial concentration. From BCF value, Lemna minor was found to be a hyperaccumulator of arsenic at initial concentration of 0.5 mg/L, such that accumulation decreased with increase in initial arsenic concentration.

  7. Arsenic and the Epigenome: Linked by Methylation(SOT)

    Science.gov (United States)

    Inorganic arsenic (iAs) is an environmental toxicant currently poisoning millions of people worldwide, and chronically-exposed individuals are susceptible to arsenic poisoning, or arsenicosis. In some exposed populations arsenicosis susceptibility is dependent in part on the abil...

  8. [Pathways of arsenic uptake in prokaryotic and eukaryotic cells].

    Science.gov (United States)

    Lis, Paweł; Litwin, Ireneusz; Maciaszczyk-Dziubińska, Ewa

    2010-01-01

    Mechanisms of arsenic uptake and detoxification are present in all studied organisms. These mechanisms are considerably well described in unicellular organisms such as bacterium Escherichia coli and baker's yeast Saccharomyces cerevisiae, still leaving much to be revealed in multicellular organisms. Full identification of arsenic uptake and detoxification is of great importance. This knowledge can be very helpful in improving effectiveness of arsenic-containing drugs used in chemotherapy of parasitoses as well as in treatment of acute promielyocytic leukemia. Increased proficiency of bioremediation of arsenic-contaminated soils can be obtained by using plants hyperaccumulating arsenic. This kind of plants can be engineered by modulating expression levels of genes encoding arsenic transporters. The same technique may be used to decrease levels of accumulated arsenic in crops. The aim of this paper is to review current knowledge about systems of arsenic uptake in every studied organism--from bacteria to human.

  9. Map of Arsenic concentrations in groundwater of the United States

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The map graphic image at http://water.usgs.gov/GIS/browse/arsenic_map.png illustrates arsenic values, in micrograms per liter, for groundwater samples from about...

  10. Mouse Assay for Determination of Arsenic Bioavailability in Contaminated Soils

    Science.gov (United States)

    Background: Accurate assessment of human exposure estimates from arsenic-contaminated soils depends upon estimating arsenic (As) soil bioavailability. Development of bioavailability assays provides data needed for human health risk assessments and supports development and valida...

  11. Uptake of Arsenic in Rice Plant Varieties Cultivated with Arsenic Rich Groundwater

    Directory of Open Access Journals (Sweden)

    Piyal Bhattacharya

    2010-07-01

    Full Text Available Groundwater of many areas of West Bengal, India is severely contaminated with arsenic. The paddy soil gets con¬taminated from the groundwater and thus there is a probability of bioaccumulation of arsenic in rice plants cultivated with arsenic contaminated groundwater and soil. This study aims at assessing the level of arsenic in irrigation water and soil and to investigate the seasonal bioaccumulation of arsenic in the various parts (straw, husk and grain of the rice plant of differ¬ent varieties in the arsenic affected two blocks (Chakdaha and Ranaghat-I of Nadia district, West Bengal. It was found that the arsenic uptake in rice during the pre-monsoon season is more than that of the post-monsoon season. The accumulation of arsenic found to vary with different rice varieties; the maximum accumulation was in White minikit (0.31±0.005 mg/kg and IR 50 (0.29±0.001 mg/kg rice varieties and minimum was found to be in the Jaya rice variety (0.14±0.002 mg/kg. In rice plant maximum arsenic accumulation occurred in the straw part (0.89±0.019-1.65±0.021 mg/kg compared to the ac¬cumulation in husk (0.31±0.011-0.85±0.016 mg/kg and grain (0.14±0.002-0.31±0.005 mg/kg parts. For any rice sample concentration of arsenic in the grain did not exceed the WHO recommended permissible limit in rice (1.0 mg/kg.

  12. Clinical manifestations and arsenic methylation after a rare subacute arsenic poisoning accident.

    Science.gov (United States)

    Xu, Yuanyuan; Wang, Yi; Zheng, Quanmei; Li, Bing; Li, Xin; Jin, Yaping; Lv, Xiuqiang; Qu, Guang; Sun, Guifan

    2008-06-01

    One hundred and four workers ingested excessive levels of arsenic in an accident caused by leakage of pipeline in a copper-smelting factory. Clinical examinations were performed by physicians in a local hospital. Excreted urinary arsenic species were determined by cold trap hydride generation atomic absorption spectrometry. In the initial toxic phase, gastrointestinal symptoms were predominant (83 people, 79.8%). Most patients showed leucopenia (72 people, 69.2%), and increased serum alanine aminotransferase (84 people, 80.8%) and aspartate aminotransferase (58 people, 55.8%). Thirty-five patients (33.6%) had elevated red blood cells in urine. After 17 days of admission, many subjects (45 people, 43.3%) developed peripheral neuropathy and 25 of these 45 patients (24.0%) showed a decrease in motor and sensory nerve conduction velocity. In the comparison of urinary arsenic metabolites among subacute arsenic-poisoned, chronic high arsenic-exposed and control subjects, we found that subacute arsenic-poisoned patients had significantly elevated proportions of urinary inorganic arsenic (iAs) and methylarsonic acid (MMA) but reduced proportion of urinary dimethylarsinic acid (DMA) compared with chronic high arsenic-exposed and control subjects. Chronic exposed subjects excreted higher proportions of iAs and MMA but lower proportions of DMA in urine compared with control subjects. These results suggest that gastrointestinal symptoms, leucopenia, and hepatic and urinary injury are predominant in the initial phase of subacute arsenic poisoning. Peripheral neuropathy is the most frequent manifestation after the initial phase. The biomethylation of arsenic decreases in a dose rate-dependent manner.

  13. Improvement of bioreporter bacteria-based test systems for the analysis of arsenic in drinking water and the rhizosphere

    Energy Technology Data Exchange (ETDEWEB)

    Kuppardt, Anke

    2010-02-05

    Contamination of drinking water with arsenic can be measured in laboratories with atom absorption spectrometry (AAS), mass spectrometry with inductive coupled plasma (ICP-MS) or atom fluorescence spectrometry (AFS) at the relevant concentrations below 50 {mu}g/L. Field test kits which easily and reliably measure arsenic concentrations are not yet available. Test systems on the basis of bioreporter bacteria offer an alternative. Based on the natural resistance mechanism of bacteria against arsenic compounds toxic for humans, bioreporter bacteria can be constructed that display arsenic concentrations with light emission (luminescence or fluorescence) or colour reactions. This is achieved by coupling the gene for the ArsR-protein and arsenic regulated promoters with suitable reporter genes. The resulting bioreporter bacteria report bioavailable arsenic in a dose dependent manner at the toxicologically relevant level of 2 to 80 {mu}g/L and are therewith suitable both for the guideline levels of the WHO of 10 {mu}g/L and for the national standards in South East Asia of 50 {mu}g/L. This alternative method has the advantage of being independent from sophisticated apparatus as by eye detection is feasible and offers the possibility of measuring directly the bioavailable fraction. Bioreporter bacteria are also suitable for in situ research. Yet, in order to apply such bioreporter bacteria as a low-cost analytical tool in a regular manner, open questions exist regarding the preservation of the specific activity, the vitality of bioreporter bacteria and the improvement of bioreporter test systems for layman. The aim of this thesis hence was to optimize and improve bioreporter based test systems to allow easy conservation, storage and transport, and also an application without the need of a sophisticated infrastructure. For that purpose it was intended (i) to develop and validate a method that allows arsenic detection without external calibration (chapter 2) and (ii) to

  14. Improvement of bioreporter bacteria-based test systems for the analysis of arsenic in drinking water and the rhizosphere

    Energy Technology Data Exchange (ETDEWEB)

    Kuppardt, Anke

    2010-02-05

    Contamination of drinking water with arsenic can be measured in laboratories with atom absorption spectrometry (AAS), mass spectrometry with inductive coupled plasma (ICP-MS) or atom fluorescence spectrometry (AFS) at the relevant concentrations below 50 {mu}g/L. Field test kits which easily and reliably measure arsenic concentrations are not yet available. Test systems on the basis of bioreporter bacteria offer an alternative. Based on the natural resistance mechanism of bacteria against arsenic compounds toxic for humans, bioreporter bacteria can be constructed that display arsenic concentrations with light emission (luminescence or fluorescence) or colour reactions. This is achieved by coupling the gene for the ArsR-protein and arsenic regulated promoters with suitable reporter genes. The resulting bioreporter bacteria report bioavailable arsenic in a dose dependent manner at the toxicologically relevant level of 2 to 80 {mu}g/L and are therewith suitable both for the guideline levels of the WHO of 10 {mu}g/L and for the national standards in South East Asia of 50 {mu}g/L. This alternative method has the advantage of being independent from sophisticated apparatus as by eye detection is feasible and offers the possibility of measuring directly the bioavailable fraction. Bioreporter bacteria are also suitable for in situ research. Yet, in order to apply such bioreporter bacteria as a low-cost analytical tool in a regular manner, open questions exist regarding the preservation of the specific activity, the vitality of bioreporter bacteria and the improvement of bioreporter test systems for layman. The aim of this thesis hence was to optimize and improve bioreporter based test systems to allow easy conservation, storage and transport, and also an application without the need of a sophisticated infrastructure. For that purpose it was intended (i) to develop and validate a method that allows arsenic detection without external calibration (chapter 2) and (ii) to

  15. Enhancement of chromosomal damage by arsenic: implications for mechanism.

    OpenAIRE

    1993-01-01

    Arsenic is a naturally occurring metalloid that has been associated with increased incidence of human cancer in certain highly exposed populations. Arsenic is released to the environment by natural means such as solubilization from geologic formations into water supplies. It is also released to occupational and community environments by such activities as nonferrous ore smelting and combustion of fuels containing arsenic. Several lines of evidence indicate that arsenic acts indirectly with ot...

  16. Solid materials for removing arsenic and method thereof

    Science.gov (United States)

    Coronado, Paul R.; Coleman, Sabre J.; Sanner, Robert D.; Dias, Victoria L.; Reynolds, John G.

    2008-07-01

    Solid materials have been developed to remove arsenic compounds from aqueous media. The arsenic is removed by passing the aqueous phase through the solid materials which can be in molded, granular, or powder form. The solid materials adsorb the arsenic leaving a purified aqueous stream. The materials are aerogels or xerogels and aerogels or xerogels and solid support structure, e.g., granulated activated carbon (GAC), mixtures. The species-specific adsorption occurs through specific chemical modifications of the solids tailored towards arsenic.

  17. Removal of arsenic from aqueous solution using electrocoagulation.

    Science.gov (United States)

    Balasubramanian, N; Kojima, Toshinori; Basha, C Ahmed; Srinivasakannan, C

    2009-08-15

    Removal of arsenic from aqueous solution was carried out using electrocoagulation. Experiments were conducted using mild steel sacrificial anode covering wide range in operating conditions to assess the removal efficiency. The maximum arsenic removal efficiency was recorded as 94% under optimum condition. The electrocoagulation mechanism of arsenic removal has been developed to understand the effect of applied charge and electrolyte pH on arsenic removal efficiency. Further the experimental data were tested with different adsorption isotherm model to describe the electrocoagulation process.

  18. Reduction, methylation, and translocation of arsenic in Panax notoginseng grown under field conditions in arsenic-contaminated soils.

    Science.gov (United States)

    Ma, Jie; Mi, Yanhua; Li, Qiwan; Chen, Lu; Du, Lijuan; He, Lizhong; Lei, Mei

    2016-04-15

    Variations in arsenic (As) species in Panax notoginseng grown under field conditions remain understudied compared with those under greenhouse conditions. In the present study, soil and plant samples were collected from Wenshan Zhuang and Miao Autonomous Prefecture, Yunnan Province, which is the main production area of P. notoginseng in China, to identify As species in the soil and plant tissues and further assess effect of As toxic stress on As transformation and translocation in P. notoginseng. The results showed that arsenate (As(V)) was almost exclusively identified in the soil, while arsenite (As(III)) and monomethylarsonic acid (MMA) were detected in high proportions in plant tissues, suggesting that As(V) could be reduced and subsequently methylated in the plant body, mainly in the root. The reduction and methylation of As in the root of P. notoginseng were promoted by low As toxic stress, but were impeded by high As toxic stress. Arsenic(III) and MMA could rapidly translocate upwards in P. notoginseng. In addition, the translocation of total As, As(III), and MMA from the root to the rhizome was a response to As toxic stress, and the translocation rate increased with the increasing As concentration in the taproot. This study provides new insights into the detoxification mechanism of P. notoginseng grown in As-contaminated soils and the control of As during cultivation.

  19. Dissolved Air Flotation of arsenic adsorbent particles

    Directory of Open Access Journals (Sweden)

    M. Santander

    2015-04-01

    Full Text Available The removal of arsenic from synthetic effluent was studied using the adsorbent particle flotation technique (APF and dissolved air flotation (DAF. A sample of an iron mineral was used as adsorbent particles of arsenic, ferric chloride as coagulant, cationic polyacrylamide (NALCO 9808 as flocculants, and sodium oleate as collector. Adsorption studies to determine the pH influence, contact time, and adsorbent particles concentration on the adsorption of arsenic were carried out along with flotation studies to determine the removal efficiency of adsorbents particles. The results achieved indicate that the adsorption kinetic of arsenic is very rapid and that in range of pH’s from 2 to 7 the adsorption percentages remain constant. The equilibrium conditions were achieved in 60 minutes and about 95% of arsenic was adsorbed when used an adsorbent concentration of 2 g/L and pH 6.3. The maximum adsorption capacity of adsorbent particles was 4.96 mg/g. The mean free energy of adsorption (E was found to be 2.63 kJ/mol, which suggests physisorption. The results of the flotation studies demonstrated that when synthetic effluents with 8.9 mg/L of arsenic were treated under the following experimental conditions; 2 g/L of adsorbent particles, 120 mg/L of Fe(III, 2 mg/L of Nalco 9808, 20 mg/L of sodium oleate, and 40% of recycle ratio in the DAF, it was possible to reach 98% of arsenic removal and 6.3 NTU of residual turbidity in clarified synthetic effluent.

  20. Arsenic management through well modification and simulation

    Science.gov (United States)

    Halford, Keith J.; Stamos, Christina L.; Nishikawa, Tracy; Martin, Peter

    2010-01-01

    Arsenic concentrations can be managed with a relatively simple strategy of grouting instead of completely destroying a selected interval of well. The strategy of selective grouting was investigated in Antelope Valley, California, where groundwater supplies most of the water demand. Naturally occurring arsenic typically exceeds concentrations of 10 (mu or u)g/L in the water produced from these long-screened wells. The vertical distributions of arsenic concentrations in intervals of the aquifer contributing water to selected supply wells were characterized with depth-dependent water-quality sampling and flow logs. Arsenic primarily entered the lower half of the wells where lacustrine clay deposits and a deeper aquifer occurred. Five wells were modified by grouting from below the top of the lacustrine clay deposits to the bottom of the well, which reduced produced arsenic concentrations to less than 2 (mu or u)g/L in four of the five wells. Long-term viability of well modification and reduction of specific capacity was assessed for well 4-54 with AnalyzeHOLE, which creates and uses axisymmetric, radial MODFLOW models. Two radial models were calibrated to observed borehole flows, drawdowns, and transmissivity by estimating hydraulicconductivity values in the aquifer system and gravel packs of the original and modified wells. Lithology also constrained hydraulic-conductivity estimates as regularization observations. Well encrustations caused as much as 2 (mu or u)g/L increase in simulated arsenic concentration by reducing the contribution of flow from the aquifer system above the lacustrine clay deposits. Simulated arsenic concentrations in the modified well remained less than 3 (mu or u)g/L over a 20-year period.

  1. Distributional patterns of arsenic concentrations in contaminant plumes offer clues to the source of arsenic in groundwater at landfills

    Science.gov (United States)

    Harte, Philip T.

    2015-01-01

    The distributional pattern of dissolved arsenic concentrations from landfill plumes can provide clues to the source of arsenic contamination. Under simple idealized conditions, arsenic concentrations along flow paths in aquifers proximal to a landfill will decrease under anthropogenic sources but potentially increase under in situ sources. This paper presents several conceptual distributional patterns of arsenic in groundwater based on the arsenic source under idealized conditions. An example of advanced subsurface mapping of dissolved arsenic with geophysical surveys, chemical monitoring, and redox fingerprinting is presented for a landfill site in New Hampshire with a complex flow pattern. Tools to assist in the mapping of arsenic in groundwater ultimately provide information on the source of contamination. Once an understanding of the arsenic contamination is achieved, appropriate remedial strategies can then be formulated.

  2. IDENTIFYING CRITICAL CYSTEINE RESIDUES IN ARSENIC (+3 OXIDATION STATE) METHYLTRANSFERASE

    Science.gov (United States)

    Arsenic (+3 oxidation state) methyltransferase (AS3MT) catalyzes methylation of inorganic arsenic to mono, di, and trimethylated arsenicals. Orthologous AS3MT genes in genomes ranging from simple echinoderm to human predict a protein with five conserved cysteine (C) residues. In ...

  3. Effect of thermal treatments on arsenic species contents in food.

    Science.gov (United States)

    Devesa, V; Vélez, D; Montoro, R

    2008-01-01

    In arsenic-endemic and other areas, food is an important path of exposure to this contaminant. Food is generally consumed in processed form, after a preservation treatment or cooking, which may alter the concentrations and chemical forms of arsenic. This article summarizes and discusses the work so far published on the effect that thermal treatment used in the cooking or processing of food, including sterilization and preservation stages, has on total arsenic and arsenic species contents. It also reviews possible transformations in arsenic species. The studies included use model systems or food products of marine or vegetable origin. Processing may cause a considerable increase or decrease in the real arsenic intake from food. For example, traditional washing and soaking of Hizikia fusiforme seaweed, which has very high inorganic arsenic contents, may reduce the contents by up to 60%. On the other hand, all the arsenic present in cooking water may be retained during boiling of rice, increasing the contents of this metalloid to significant levels from a toxicological viewpoint. This calls for modifications in arsenic risk assessment, hitherto based on analysis of the raw product. It is necessary to consider the effect of processing on total arsenic and arsenical species in order to obtain a realistic view of the risk associated with intake in arsenic-endemic and other areas.

  4. 21 CFR 862.3120 - Arsenic test system.

    Science.gov (United States)

    2010-04-01

    ... arsenic, a poisonous heavy metal, in urine, vomitus, stomach contents, nails, hair, and blood. Measurements obtained by this device are used in the diagnosis and treatment of arsenic poisoning. (b... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Arsenic test system. 862.3120 Section...

  5. The Arsenic Project: A multidisciplinary Project in Nicaragua

    NARCIS (Netherlands)

    Admiraal, M.; Couasnon, A.; Huijzenveld, T.; Hutten, R.; Schölvinck, O.; Van Veen, N.

    2015-01-01

    In Nicaragua, active research for arsenic started in 1996, after the first case of arsenic poisoning was reported in a rural community. Arsenic concentrations present in drinking water cause chronic poisoning, which depending on the exposure, lead to several life-threatening long term effects. It i

  6. Granulocyte colony-stimulating factor potentiates differentiation induction by all-trans retinoic acid and arsenic trioxide and enhances arsenic uptake in the acute promyelocytic leukemia cell line HT93A.

    Science.gov (United States)

    Iriyama, Noriyoshi; Yuan, Bo; Hatta, Yoshihiro; Horikoshi, Akira; Yoshino, Yuta; Toyoda, Hiroo; Aizawa, Shin; Takeuchi, Jin

    2012-11-01

    The effects of arsenic trioxide (ATO), all-trans retinoic acid (ATRA) and granulocyte colony-stimulating factor (G-CSF), alone or in combination, were investigated by focusing on differentiation, growth inhibition and arsenic uptake in the acute promyelocytic leukemia (APL) cell line HT93A. ATO induced differentiation at low concentrations (0.125 µM) and apoptosis at high concentrations (1-2 µM). Furthermore, ATRA induced greater differentiation than ATO. No synergistic effect of ATRA and ATO was found on differentiation. G-CSF promoted differentiation-inducing activities of both ATO and ATRA. The combination of ATRA and G-CSF showed maximum differentiation and ATO addition was not beneficial. Addition of 1 µM ATRA and/or 50 ng/ml G-CSF to ATO did not affect apoptosis compared to ATO treatment alone. ATRA induced expression of aquaporin-9 (AQP9), a transmembrane transporter recognized as a major pathway of arsenic uptake, in a time- and dose-dependent manner. However, treatment with 1 µM ATRA decreased arsenic uptake by 43.7% compared to control subject. Although G-CSF addition did not enhance AQP9 expression in the cells, the reduced arsenic uptake was recovered to the same level as that in controls. ATRA decreased cell viability and addition of 50 ng/ml G-CSF to ATRA significantly increased the number of viable cells compared with that in ATRA alone treated cells. G-CSF not only promotes differentiation-inducing activities of both ATRA and ATO, but also makes APL cells vulnerable to increased arsenic uptake. These observations provide new insights into combination therapy using these three agents for the treatment of APL.

  7. Roxarsone, Inorganic Arsenic, and Other Arsenic Species in Chicken: A U.S.-Based Market Basket Sample

    OpenAIRE

    Nachman, Keeve E.; Baron, Patrick A; Raber, Georg; Francesconi, Kevin A.; Navas-Acien, Ana; Love, David C.

    2013-01-01

    Background: Inorganic arsenic (iAs) causes cancer and possibly other adverse health outcomes. Arsenic-based drugs are permitted in poultry production; however, the contribution of chicken consumption to iAs intake is unknown. Objectives: We sought to characterize the arsenic species profile in chicken meat and estimate bladder and lung cancer risk associated with consuming chicken produced with arsenic-based drugs. Methods: Conventional, antibiotic-free, and organic chicken samples were colle...

  8. Mineralogy and arsenic mobility in arsenic-rich Brazilian soils and sediments

    Science.gov (United States)

    de Mello, J.W.V.; Roy, W.R.; Talbott, J.L.; Stucki, J.W.

    2006-01-01

    Background. Soils and sediments in certain mining regions of Brazil contain an unusually large amount of arsenic (As), which raises concerns that mining could promote increased As mobility, and thereby increase the risks of contaminating water supplies. Objectives. The purpose of t his study was to identify the most important factors governing As mobility in sediments and soils near three gold-mining sites in the State of Minas Gerais, Brazil. Methods. Surface and sub-surface soil samples were collected at those sites and characterized by chemical and mineralogical analyses. Oxalate (Feo) and citrate-bicarbonate-dithionite (Fed) iron contents were determined by atomic absorption spectroscopy (AAS). Arsenic mobilization was measured after incubating the samples in a 2.5 mM CaCl2 solution under anaerobic conditions for 1, 28, 56, 84, or 112 days. The solution concentrations of As, Fe, and Mn were then measured by inductively coupled plasma-mass spectrometry (ICP-MS) and AAS, respectively. Results and Discussion. Results indicated that As mobilization is largely independent of both the total As and the Feo/Fed ratio of the solid phase. Soluble As is roughly controlled by the Fe (hydr)oxide content of the soil, but a closer examination of the data revealed the importance of other highly weathered clay minerals and organic matter. Large amounts of organic matter and a low iron oxide content should favor As leaching from soils and sediments. Under reducing conditions, As is mobilized by the reductive dissolution of Fe and/or Mn oxides. However, released As may be readsorbed depending on the sorptive properties of the soil. Gibbsite is particularly effective in adsorbing or readsorbing As, as is the remaining unreduced fraction of the iron (hydr)oxides. Conclusion and Outlook. In general, low soluble As is rel ated to the presence of gibbsite, a large amount of iron oxides, and a lack of organic matter in the solid phase. This has environmental significance because

  9. Chronic occupational exposure to arsenic induces carcinogenic gene signaling networks and neoplastic transformation in human lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Stueckle, Todd A., E-mail: tstueckle@hsc.wvu.edu [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States); Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505 (United States); Lu, Yongju, E-mail: yongju6@hotmail.com [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States); Davis, Mary E., E-mail: mdavis@wvu.edu [Department of Physiology, West Virginia University, Morgantown, WV 26506 (United States); Wang, Liying, E-mail: lmw6@cdc.gov [Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505 (United States); Jiang, Bing-Hua, E-mail: bhjiang@jefferson.edu [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Holaskova, Ida, E-mail: iholaskova@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Schafer, Rosana, E-mail: rschafer@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Barnett, John B., E-mail: jbarnett@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Rojanasakul, Yon, E-mail: yrojan@hsc.wvu.edu [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States)

    2012-06-01

    Chronic arsenic exposure remains a human health risk; however a clear mode of action to understand gene signaling-driven arsenic carcinogenesis is currently lacking. This study chronically exposed human lung epithelial BEAS-2B cells to low-dose arsenic trioxide to elucidate cancer promoting gene signaling networks associated with arsenic-transformed (B-As) cells. Following a 6 month exposure, exposed cells were assessed for enhanced cell proliferation, colony formation, invasion ability and in vivo tumor formation compared to control cell lines. Collected mRNA was subjected to whole genome expression microarray profiling followed by in silico Ingenuity Pathway Analysis (IPA) to identify lung carcinogenesis modes of action. B-As cells displayed significant increases in proliferation, colony formation and invasion ability compared to BEAS-2B cells. B-As injections into nude mice resulted in development of primary and secondary metastatic tumors. Arsenic exposure resulted in widespread up-regulation of genes associated with mitochondrial metabolism and increased reactive oxygen species protection suggesting mitochondrial dysfunction. Carcinogenic initiation via reactive oxygen species and epigenetic mechanisms was further supported by altered DNA repair, histone, and ROS-sensitive signaling. NF-κB, MAPK and NCOR1 signaling disrupted PPARα/δ-mediated lipid homeostasis. A ‘pro-cancer’ gene signaling network identified increased survival, proliferation, inflammation, metabolism, anti-apoptosis and mobility signaling. IPA-ranked signaling networks identified altered p21, EF1α, Akt, MAPK, and NF-κB signaling networks promoting genetic disorder, altered cell cycle, cancer and changes in nucleic acid and energy metabolism. In conclusion, transformed B-As cells with their whole genome expression profile provide an in vitro arsenic model for future lung cancer signaling research and data for chronic arsenic exposure risk assessment. Highlights: ► Chronic As{sub 2}O

  10. Purification and characterization of thiols in an arsenic hyperaccumulator under arsenic exposure.

    Science.gov (United States)

    Zhang, Weihua; Cai, Yong

    2003-12-15

    Pteris vittata (Chinese brake fern) is the first reported arsenic hyperaccumulator. To investigate the arsenic tolerance mechanism in this plant, reversed-phase HPLC with postcolumn derivatization was used to analyze the thiols induced under arsenic exposure. A major thiol in the plant leaflets was found to be responsive to arsenic exposure. The arsenic-induced compound was purified on a large scale by combining covalent chromatography and preparative reversed-phase HPLC. About 2 mg of this compound was isolated from 1 kg of fresh leaflets. The purified arsenic-induced compound was characterized using electrospray ionization mass spectrometry. A molecular ion (M + 1) of 540 and fragments were obtained, which indicated that the arsenic-induced thiol was a phytochelatin with two subunits (PC(2)). Compared to the classical methods for purification of phytochelatins, this new method is more specific, simple, and rapid and is suitable for purification of PCs in a large scale as well as sample preparation for mass spectrometry analysis.

  11. Metallothionein does not sequester arsenic(III) ions in condition of acute arsenic toxicity.

    Science.gov (United States)

    Garla, Roobee; Ganger, Renuka; Mohanty, Biraja P; Verma, Shivcharan; Bansal, Mohinder P; Garg, Mohan L

    2016-07-29

    The major cause of toxicity of trivalent arsenicals is due to their interaction with the sulfhydryl groups in proteins. Because of its high content, Metallothionein (MT) provides one of the most favorable conditions for the binding of As(III) ions to it. MT has long been anticipated for providing resistance in case of arsenic (As) toxicity with similar mechanism as in case of cadmium toxicity. The present study investigates whether the sequestration of As ions by MT is one of the mechanisms in providing protection against acute arsenic toxicity. A rat model study on the metal stoichiometric analysis of MT1 isoform isolated from the liver of arsenic treated, untreated and zinc treated animals has been carried out using the combination of particle induced X-ray emission (PIXE) and electrospray ionisation mass spectrometry (ESI-MS). The results revealed the absence of arsenic bound MT1 in the samples isolated from arsenic treated animals. Although, both Cu and Zn ions were present in MT1 samples isolated from all the treatment groups. Moreover, only partially metallated MT1 with varying number of Zn ions were observed in all the groups. These results suggest that the role of MT during acute arsenic toxicity is different from its already established role in case of cadmium toxicity.

  12. Arsenic speciation in rice and risk assessment of inorganic arsenic in Taiwan population.

    Science.gov (United States)

    Chen, Hsiu-Ling; Lee, Ching-Chang; Huang, Winn-Jung; Huang, Han-Ting; Wu, Yi-Chen; Hsu, Ya-Chen; Kao, Yi-Ting

    2016-03-01

    This study assessed the total arsenic content and arsenic speciation in rice to determine the health risks associated with rice consumption in various age-gender subgroups in Taiwan. The average total arsenic levels in white rice and brown rice were 116.6 ± 39.2 and 215.5 ± 63.5 ng/g weight (n = 51 and 13), respectively. The cumulative cancer risk among males was 10.4/100,000. The highest fraction of inorganic/total arsenic content in white rice ranged from 76.9 to 88.2 % and from 81.0 to 96.5 % in brown rice. The current study found different arsenic speciation of rice in southern Taiwan, where the famous blackfoot disease has been reported compared with arsenic speciation from other Taiwan areas. Therefore, rice and other grains should be further monitored in southern Taiwan to evaluate whether arsenic contamination is well controlled in this area.

  13. Chronic Arsenic Poisoning Probably Caused by Arsenic-Based Pesticides: Findings from an Investigation Study of a Household

    Directory of Open Access Journals (Sweden)

    Yongfang Li

    2016-01-01

    Full Text Available In addition to naturally occurring arsenic, man-made arsenic-based compounds are other sources of arsenic exposure. In 2013, our group identified 12 suspected arsenicosis patients in a household (32 living members. Of them, eight members were diagnosed with skin cancer. Interestingly, all of these patients had lived in the household prior to 1989. An investigation revealed that approximately 2 tons of arsenic-based pesticides had been previously placed near a well that had supplied drinking water to the family from 1973 to 1989. The current arsenic level in the well water was 620 μg/L. No other high arsenic wells were found near the family’s residence. Based on these findings, it is possible to infer that the skin lesions exhibited by these family members were caused by long-term exposure to well water contaminated with arsenic-based pesticides. Additionally, biochemical analysis showed that the individuals exposed to arsenic had higher levels of aspartate aminotransferase and γ-glutamyl transpeptidase than those who were not exposed. These findings might indicate the presence of liver dysfunction in the arsenic-exposed individuals. This report elucidates the effects of arsenical compounds on the occurrence of high levels of arsenic in the environment and emphasizes the severe human health impact of arsenic exposure.

  14. Chronic Arsenic Poisoning Probably Caused by Arsenic-Based Pesticides: Findings from an Investigation Study of a Household.

    Science.gov (United States)

    Li, Yongfang; Ye, Feng; Wang, Anwei; Wang, Da; Yang, Boyi; Zheng, Quanmei; Sun, Guifan; Gao, Xinghua

    2016-01-16

    In addition to naturally occurring arsenic, man-made arsenic-based compounds are other sources of arsenic exposure. In 2013, our group identified 12 suspected arsenicosis patients in a household (32 living members). Of them, eight members were diagnosed with skin cancer. Interestingly, all of these patients had lived in the household prior to 1989. An investigation revealed that approximately 2 tons of arsenic-based pesticides had been previously placed near a well that had supplied drinking water to the family from 1973 to 1989. The current arsenic level in the well water was 620 μg/L. No other high arsenic wells were found near the family's residence. Based on these findings, it is possible to infer that the skin lesions exhibited by these family members were caused by long-term exposure to well water contaminated with arsenic-based pesticides. Additionally, biochemical analysis showed that the individuals exposed to arsenic had higher levels of aspartate aminotransferase and γ-glutamyl transpeptidase than those who were not exposed. These findings might indicate the presence of liver dysfunction in the arsenic-exposed individuals. This report elucidates the effects of arsenical compounds on the occurrence of high levels of arsenic in the environment and emphasizes the severe human health impact of arsenic exposure.

  15. Chronic Arsenic Poisoning Probably Caused by Arsenic-Based Pesticides: Findings from an Investigation Study of a Household

    Science.gov (United States)

    Li, Yongfang; Ye, Feng; Wang, Anwei; Wang, Da; Yang, Boyi; Zheng, Quanmei; Sun, Guifan; Gao, Xinghua

    2016-01-01

    In addition to naturally occurring arsenic, man-made arsenic-based compounds are other sources of arsenic exposure. In 2013, our group identified 12 suspected arsenicosis patients in a household (32 living members). Of them, eight members were diagnosed with skin cancer. Interestingly, all of these patients had lived in the household prior to 1989. An investigation revealed that approximately 2 tons of arsenic-based pesticides had been previously placed near a well that had supplied drinking water to the family from 1973 to 1989. The current arsenic level in the well water was 620 μg/L. No other high arsenic wells were found near the family’s residence. Based on these findings, it is possible to infer that the skin lesions exhibited by these family members were caused by long-term exposure to well water contaminated with arsenic-based pesticides. Additionally, biochemical analysis showed that the individuals exposed to arsenic had higher levels of aspartate aminotransferase and γ-glutamyl transpeptidase than those who were not exposed. These findings might indicate the presence of liver dysfunction in the arsenic-exposed individuals. This report elucidates the effects of arsenical compounds on the occurrence of high levels of arsenic in the environment and emphasizes the severe human health impact of arsenic exposure. PMID:26784217

  16. Urinary arsenic speciation and its correlation with 8-OHdG in Chinese residents exposed to arsenic through coal burning

    Energy Technology Data Exchange (ETDEWEB)

    Li, X.; Pi, J.B.; Li, B.; Xu, Y.Y.; Jin, Y.P.; Sun, G.F. [China Medical University, Shenyang (China). Dept. for Occupational & Environmental Health

    2008-10-15

    In contrast to arsenicosis caused by consumption of water contaminated by naturally occurring inorganic arsenic, human exposure to this metalloid through coal burning has been rarely reported. In this study, arsenic speciation and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in urine were determined in the Chinese residents exposed to arsenic through coal burning in Guizhou, China, an epidemic area of chronic arsenic poisoning caused by coal burning. The urinary concentrations of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and total arsenic (tAs) of high-arsenic exposed subjects were significantly higher than those of low-arsenic exposed residents. A biomarker of oxidative DNA damage, urinary 8-OHdG level was significantly higher in high-arsenic exposed subjects than that of low exposed. Significant positive correlations were found between 8-OHdG levels and concentrations of iAs, MMA, DMA and tAs, respectively. In addition, a significant negative correlation was observed between 8-OHdG levels and the secondary methylation ratio (DMA/(MMA + DMA)). The results suggest that chronic arsenic exposure through burning coal rich in arsenic is associated with oxidative DNA damages, and that secondary methylation capacity is potentially related to the susceptibility of individuals to oxidative DNA damage induced by arsenic exposure through coal burning in domestic living.

  17. LDH-A promotes malignant progression via activation of epithelial-to-mesenchymal transition and conferring stemness in muscle-invasive bladder cancer.

    Science.gov (United States)

    Jiang, Fujin; Ma, Song; Xue, Yubao; Hou, Jianquan; Zhang, Yongjie

    2016-01-22

    Lactate dehydrogenase-A(LDH-A) is an important rate-limiting enzyme in the Warburg effect. Survival analysis indicated poor clinical outcomes in MIBC with high LDH-A expression. The results of in vitro experiment indicated that LDH-A promotes MIBC cells proliferation, invasion and migration. The positive relationship between LDH-A expression and CSC/EMT markers was confirmed both in invasive bladder cell line and in 136 MIBC specimens. Thus, we conclude that LDH-A may be a promising target for MIBC.

  18. Occurrence of arsenic contamination in Canada: sources, behavior and distribution.

    Science.gov (United States)

    Wang, Suiling; Mulligan, Catherine N

    2006-08-01

    Recently there has been increasing anxieties concerning arsenic related problems. Occurrence of arsenic contamination has been reported worldwide. In Canada, the main natural arsenic sources are weathering and erosion of arsenic-containing rocks and soil, while tailings from historic and recent gold mine operations and wood preservative facilities are the principal anthropogenic sources. Across Canada, the 24-h average concentration of arsenic in the atmosphere is generally less than 0.3 microg/m3. Arsenic concentrations in natural uncontaminated soil and sediments range from 4 to 150 mg/kg. In uncontaminated surface and ground waters, the arsenic concentration ranges from 0.001 to 0.005 mg/L. As a result of anthropogenic inputs, elevated arsenic levels, above ten to thousand times the Interim Maximum Acceptable Concentration (IMAC), have been reported in air, soil and sediment, surface water and groundwater, and biota in several regions. Most arsenic is of toxic inorganic forms. It is critical to recognize that such contamination imposes serious harmful effects on various aquatic and terrestrial organisms and human health ultimately. Serious incidences of acute and chronic arsenic poisonings have been revealed. Through examination of the available literature, screening and selecting existing data, this paper provides an analysis of the currently available information on recognized problem areas, and an overview of current knowledge of the principal hydrogeochemical processes of arsenic transportation and transformation. However, a more detailed understanding of local sources of arsenic and mechanisms of arsenic release is required. More extensive studies will be required for building practical guidance on avoiding and reducing arsenic contamination. Bioremediation and hyperaccumulation are emerging innovative technologies for the remediation of arsenic contaminated sites. Natural attenuation may be utilized as a potential in situ remedial option. Further

  19. Research progress on promoting the growth of probiotics by traditional Chinese medicine%中药促进益生菌生长的研究进展

    Institute of Scientific and Technical Information of China (English)

    刘晋仙; 林永强; 汪冰; 崔伟亮; 李慧芬

    2015-01-01

    In recent years,the importance of probiotics to human's health has been paid more and more attention. Many scholars found that traditional Chinese medicine(TCM)had a significant effect on promoting the growth of gut probiotics and adjusting the gut flora disorder. This review selected the researching on TCM promoted the growth of gut probiotics for the further research of Chinese materiamedica and microecology of TCM.%近年来,益生菌对宿主健康的重要性越来越受到重视,诸多学者研究发现中药在促进肠道益生菌生长,调节肠道菌群紊乱等方面作用显著。现将近年来中药促进肠道益生菌生长的研究做一综述,以期为中药学及中医药微生态学的深入研究提供理论依据。

  20. Overexpression of N-terminal kinase like gene promotes tumorigenicity of hepatocellular carcinoma by regulating cell cycle progression and cell motility.

    Science.gov (United States)

    Wang, Jian; Liu, Ming; Chen, Leilei; Chan, Tim Hon Man; Jiang, Lingxi; Yuan, Yun-Fei; Guan, Xin-Yuan

    2015-01-30

    Amplification and overexpression of CHD1L is one of the most frequent genetic alterations in hepatocellular carcinoma (HCC). Here we found that one of CHD1L downstream targets, NTKL, was frequently upregulated in HCC, which was significantly correlated with vascular invasion (P = 0.012) and poor prognosis (P = 0.050) of HCC. ChIP assay demonstrated the binding of CHD1L to the promoter region of NTKL. QRT-PCR study showed that the expression of NTKL positively correlated with CHD1L expression in both clinical samples and cell lines. Functional study found that NTKL had strong oncogenic roles, including increased cell growth, colony formation in soft agar, and tumor formation in nude mice. Further study found that NTKL could promote G1/S transition by decreasing P53 and increasing CyclinD1 expressions. NTKL overexpression could accelerate the mitotic exit and chromosome segregation, which led to the cytokinesis failure and subsequently induced apoptosis. NTKL also regulated cell motility by facilitating philopodia and lamellipodia formation through regulating F-actin reorganization and the phosphorylation of small GTPase Rac1/cdc42. Using co-IP and mass spectrometry approach, we identified the large GTPase dynamin2 as an interacting protein of NTKL, which might be responsible for the phenotype alterations caused by NTKL overexpression, such as cytokinesis failure, increased cell motility and abnormal of cell division.

  1. Groundwater arsenic contamination in Bangladesh-21 Years of research.

    Science.gov (United States)

    Chakraborti, Dipankar; Rahman, Mohammad Mahmudur; Mukherjee, Amitava; Alauddin, Mohammad; Hassan, Manzurul; Dutta, Rathindra Nath; Pati, Shymapada; Mukherjee, Subhash Chandra; Roy, Shibtosh; Quamruzzman, Quazi; Rahman, Mahmuder; Morshed, Salim; Islam, Tanzima; Sorif, Shaharir; Selim, Md; Islam, Md Razaul; Hossain, Md Monower

    2015-01-01

    Department of Public Health Engineering (DPHE), Bangladesh first identified their groundwater arsenic contamination in 1993. But before the international arsenic conference in Dhaka in February 1998, the problem was not widely accepted. Even in the international arsenic conference in West-Bengal, India in February, 1995, representatives of international agencies in Bangladesh and Bangladesh government attended the conference but they denied the groundwater arsenic contamination in Bangladesh. School of Environmental Studies (SOES), Jadavpur University, Kolkata, India first identified arsenic patient in Bangladesh in 1992 and informed WHO, UNICEF of Bangladesh and Govt. of Bangladesh from April 1994 to August 1995. British Geological Survey (BGS) dug hand tube-wells in Bangladesh in 1980s and early 1990s but they did not test the water for arsenic. Again BGS came back to Bangladesh in 1992 to assess the quality of the water of the tube-wells they installed but they still did not test for arsenic when groundwater arsenic contamination and its health effects in West Bengal in Bengal delta was already published in WHO Bulletin in 1988. From December 1996, SOES in collaboration with Dhaka Community Hospital (DCH), Bangladesh started analyzing hand tube-wells for arsenic from all 64 districts in four geomorphologic regions of Bangladesh. So far over 54,000 tube-well water samples had been analyzed by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS). From SOES water analysis data at present we could assess status of arsenic groundwater contamination in four geo-morphological regions of Bangladesh and location of possible arsenic safe groundwater. SOES and DCH also made some preliminary work with their medical team to identify patients suffering from arsenic related diseases. SOES further analyzed few thousands biological samples (hair, nail, urine and skin scales) and foodstuffs for arsenic to know arsenic body burden and people sub

  2. Arsenic Exposure and the Induction of Human Cancers

    Directory of Open Access Journals (Sweden)

    Victor D. Martinez

    2011-01-01

    Full Text Available Arsenic is a metalloid, that is, considered to be a human carcinogen. Millions of individuals worldwide are chronically exposed through drinking water, with consequences ranging from acute toxicities to development of malignancies, such as skin and lung cancer. Despite well-known arsenic-related health effects, the molecular mechanisms involved are not fully understood; however, the arsenic biotransformation process, which includes methylation changes, is thought to play a key role. This paper explores the relationship of arsenic exposure with cancer development and summarizes current knowledge of the potential mechanisms that may contribute to the neoplastic processes observed in arsenic exposed human populations.

  3. ARSENIC DEGRADATION BY Pseudomonas aeruginosa FOR WATER BIOREMEDIATION. PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    Esther E. Pellizzari

    2015-03-01

    Full Text Available The aim of this study was to investigate the arsenic resistance in pure cultivations of Pseudomonas aeruginosa isolated from Presidencia Roque Sáenz Peña groundwater (Chaco province, and evaluate the possibility of its use to remove arsenic from groundwater. Strains were immobilized in natural stone and cultivated in salts broth and 1 mgAs/L. The arsenic resistance and biofilm formation were observed, obtaining interaction between cells, rock and arsenic. Arsenic removal was evaluated during 3 months and its final percentage of the experiment was 60%.

  4. Resistance mechanisms to arsenicals and antimonials.

    Science.gov (United States)

    Rosen, B P

    1995-01-01

    Salts and organic derivatives of arsenic and antimony are quite toxic. Living organisms have adapted to this toxicity by the evolution of resistance mechanisms. Both prokaryotic and eukaryotic cells develop resistance when exposed to arsenicals or antimonials. In the case of bacteria resistance is conferred by plasmid-encoded arsenical resistance (ars) operons. The genes and gene products of the ars operon of the clinically-isolated conjugative R-factor R773 have been identified and their mechanism of action elucidated. The operon encodes an ATP-driven pump that extrudes arsenite and antimonite from the cells. The lowering of their intracellular concentration results in resistance. Arsenate resistance results from the action of the plasmid-encoded arsenate reductase that reduces arsenate to arsenite, which is then pumped out of the cell.

  5. Speciation of arsenic in sulfidic waters

    Directory of Open Access Journals (Sweden)

    Ford Robert G

    2003-03-01

    Full Text Available Formation constants for thioarsenite species have been determined in dilute solutions at 25°C, ΣH2S from 10-7.5 to 10-3.0 M, ΣAs from 10-5.6 to 10-4.8 M, and pH 7 and 10. The principal inorganic arsenic species in anoxic aquatic systems are arsenite, As(OH30, and a mononuclear thioarsenite with an S/As ratio of 3:1. Thioarsenic species with S/As ratios of 1 : 1,2 : 1, and 4 : 1 are lesser components in sulfidic solutions that might be encountered in natural aquatic environments. Thioarsenites dominate arsenic speciation at sulfide concentrations > 10-4.3 M at neutral pH. Conversion from neutral As(OH30 to anionic thioarsenite species may regulate the transport and fate of arsenic in sulfate-reducing environments by governing sorption and mineral precipitation reactions.

  6. Current developments in toxicological research on arsenic.

    Science.gov (United States)

    Bolt, Hermann M

    2013-01-01

    There is a plethora of recent publications on all aspects relevant to the toxicology of arsenic (As). Over centuries exposures to arsenic continue to be a major public health problem in many countries. In particular, the occurrence of high As concentrations in groundwater of Southeast Asia receives now much attention. Therefore, arsenic is a high-priority matter for toxicological research. Key exposure to As are (traditional) medicines, combustion of As-rich coal, presence of As in groundwater, and pollution due to mining activities. As-induced cardiovascular disorders and carcinogenesis present themselves as a major research focus. The high priority of this issue is now recognized politically in a number of countries, research funds have been made available. Also experimental research on toxicokinetics and toxicodynamics and on modes of toxic action is moving very rapidly. The matter is of high regulatory concern, and effective preventive measures are required in a number of countries.

  7. DNA Hypomethylation and Histone Variant macroH2A1 Synergistically Attenuate Chemotherapy-Induced Senescence to Promote Hepatocellular Carcinoma Progression

    Science.gov (United States)

    Borghesan, Michela; Fusilli, Caterina; Rappa, Francesca; Panebianco, Concetta; Rizzo, Giovanni; Oben, Jude A.; Mazzoccoli, Gianluigi; Faulkes, Chris; Pata, Illar; Agodi, Antonella; Rezaee, Farhad; Minogue, Shane; Warren, Alessandra; Peterson, Abigail; Sedivy, John M.; Douet, Julien; Buschbeck, Marcus; Cappello, Francesco; Mazza, Tommaso; Pazienza, Valerio; Vinciguerra, Manlio

    2016-01-01

    Aging is a major risk factor for progression of liver diseases to hepatocellular carcinoma (HCC). Cellular senescence contributes to age-related tissue dysfunction, but the epigenetic basis underlying drug-induced senescence remains unclear.macroH2A1, a variant of histone H2A, is a marker of senescence-associated heterochromatic foci that synergizes with DNA methylation to silence tumor-suppressor genes in human fibroblasts. In this study, we investigated the relationship between macroH2A1 splice variants, macroH2A1.1 and macroH2A1.2, and liver carcinogenesis. We found that protein levels of both macroH2A1 isoforms were increased in the livers of very elderly rodents and humans, and were robust immunohistochemical markers of human cirrhosis and HCC. In response to the chemotherapeutic and DNA-demethylating agent 5-aza-deoxycytidine (5-aza-dC), transgenic expression of macroH2A1 isoforms in HCC cell lines prevented the emergence of a senescent-like phenotype and induced synergistic global DNA hypomethylation. Conversely, macroH2A1 depletion amplified the antiproliferative effects of 5-aza-dC in HCC cells, but failed to enhance senescence. Senescence-associated secretory phenotype and whole-transcriptome analyses implicated the p38 MAPK/IL8 pathway in mediating macroH2A1-dependent escape of HCC cells from chemotherapy-induced senescence. Furthermore, chromatin immunoprecipitation sequencing revealed that this hepatic antisenescence state also required active transcription that could not be attributed to genomic occupancy of these histones. Collectively, our findings reveal a new mechanism by which drug-induced senescence is epigenetically regulated by macroH2A1 and DNA methylation and suggest macroH2A1 as a novel biomarker of hepatic senescence that could potentially predict prognosis and disease progression. PMID:26772755

  8. Arsenic in the environment: enrichments in the Slovenian soils

    Directory of Open Access Journals (Sweden)

    Mateja Gosar

    2005-12-01

    Full Text Available Arsenic, a toxic element with metalloid properties, is found in detectable concentrations in environmental samples. In nature it is enriched in metal (sulphide ore deposits, mainly as arsenides of Cu, Ni and Fe. Arsenic compounds are used mainly in agricultureand forestry as pesticides and herbicides. The ecosystem can be contaminated with arsenic via both natural and anthropogenic sources. Uses of arsenic contaminated water present so far the greatest health hazard. Occurrences of mining related arsenic problems havealso been recorded in many parts of the world.The impact of mining and metallurgic industry with regard to arsenic contents in soils in some potentially contaminated areas in Slovenia is discussed. Enriched contents of arsenic were found in Mežica. Arsenic correlates very well with lead, zinc and other heavymetals which are enriched as a result of long lasting lead production in the area. Also in Celje and Jesenice arsenic has the same distribution pattern as other anthropogenically introduced pollutants. In Idrija there are some slightly arsenic enriched areas, but there is no correlation with mercury, so the origin of arsenic in not clear yet.

  9. The Case for Visual Analytics of Arsenic Concentrations in Foods

    Directory of Open Access Journals (Sweden)

    Omotayo R. Awofolu

    2010-04-01

    Full Text Available Arsenic is a naturally occurring toxic metal and its presence in food could be a potential risk to the health of both humans and animals. Prolonged ingestion of arsenic contaminated water may result in manifestations of toxicity in all systems of the body. Visual Analytics is a multidisciplinary field that is defined as the science of analytical reasoning facilitated by interactive visual interfaces. The concentrations of arsenic vary in foods making it impractical and impossible to provide regulatory limit for each food. This review article presents a case for the use of visual analytics approaches to provide comparative assessment of arsenic in various foods. The topics covered include (i metabolism of arsenic in the human body; (ii arsenic concentrations in various foods; (ii factors affecting arsenic uptake in plants; (ii introduction to visual analytics; and (iv benefits of visual analytics for comparative assessment of arsenic concentration in foods. Visual analytics can provide an information superstructure of arsenic in various foods to permit insightful comparative risk assessment of the diverse and continually expanding data on arsenic in food groups in the context of country of study or origin, year of study, method of analysis and arsenic species.

  10. Establishment of Groundwater Arsenic Potential Distribution and Discrimination in Taiwan

    Science.gov (United States)

    Tsai, Kuo Sheng; Chen, Yu Ying; Chung Liu, Chih; Lin, Chien Wen

    2016-04-01

    According to the last 10 years groundwater monitoring data in Taiwan, Arsenic concentration increase rapidly in some areas, similar to Bengal and India, the main source of Arsenic-polluted groundwater is geological sediments, through reducing reactions. There are many researches indicate that high concentration of Arsenic in groundwater poses the risk to water safety, for example, the farm lands irrigation water contains Arsenic cause the concentration of Arsenic increase in soil and crops. Based on the management of water usage instead of remediation in the situation of insufficient water. Taiwan EPA has been developed the procedures of Arsenic contamination potential area establishment and source discriminated process. Taiwan EPA use the procedures to determine the management of using groundwater, and the proposing usage of Arsenic groundwater accordance with different objects. Agencies could cooperate with the water quality standard or water needs, studying appropriate water purification methods and the groundwater depth, water consumption, thus achieve the goal of water safety and environmental protection, as a reference of policy to control total Arsenic concentration in groundwater. Keywords: Arsenic; Distribution; Discrimination; Pollution potential area of Arsenic; Origin evaluation of groundwater Arsenic

  11. ARSENIC CONTAMINATION IN DRINKING WATER: AN ASSESSMENT FOR TURKEY

    Directory of Open Access Journals (Sweden)

    Meltem BİLİCİ ÇALIŞKAN

    2009-01-01

    Full Text Available Arsenic is one of the most abundant elements in the earth's crust and classified as a non-metal or a metalloid. Arsenic is toxic and carcinogen and in the environment occurs from both natural and anthropogenic sources. In the aqueous environment inorganic arsenic appears commonly in forms of arsenite (As(III and arsenate (As(V. pH, redox potential, and the presence of complexing ions such as ions of sulfur, iron, and calcium determine the arsenic valence and speciation. Because of the naturally occurring arsenic contamination in groundwater in many parts of the world many people have faced with risk of arsenic poisoning. In Turkey especially in the west regions, natural water sources contained much higher levels of arsenic than maximum contaminated level (MCL set (10 ?g/L were determined. In this study, arsenic problem and its reasons in Turkey were investigated. For this purpose, arsenic analyses were carried out and higher levels of arsenic than MCL was detected in some regions of Izmir. High levels of arsenic in these natural waters were considered to be associated with the dissolution of some minerals and rock formation.

  12. Coping with arsenic-based pesticides on Dine (Navajo) textiles

    Science.gov (United States)

    Anderson, Jae R.

    Arsenic-based pesticide residues have been detected on Arizona State Museum's (ASM) Dine (Navajo) textile collection using a handheld portable X-ray (pXRF) spectrometer. The removal of this toxic pesticide from historic textiles in museums collections is necessary to reduce potential health risks to Native American communities, museum professionals, and visitors. The research objective was divided into three interconnected stages: (1) empirically calibrate the pXRF instrument for arsenic contaminated cotton and wool textiles; (2) engineer an aqueous washing treatment exploring the effects of time, temperature, agitation, and pH conditions to efficiently remove arsenic from wool textiles while minimizing damage to the structure and properties of the textile; (3) demonstrate the devised aqueous washing treatment method on three historic Navajo textiles known to have arsenic-based pesticide residues. The preliminary results removed 96% of arsenic from a high arsenic concentration (~1000 ppm) textile opposed to minimal change for low arsenic concentration textiles (<100 ppm).

  13. Arsenic detection in water: YPO4:Eu3+ nanoparticles

    Science.gov (United States)

    Ghosh, Debasish; Luwang, Meitram Niraj

    2015-12-01

    This work reports on the novel technique of detection of arsenic in aqueous solution utilising the luminescence properties of lanthanide doped nanomaterials. Eu3+ (5%) doped YPO4nanorodswere utilised for the said experiment. Co-precipitation method was used for the synthesis of the materials and characterised them with different instrumental techniques like X-ray diffraction (XRD), Infra-red (IR), UV-absorption, scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence studies. This nanoparticle can adsorb both arsenic and arsenious acids. We studied the effect of arsenic adsorption on the luminescence behaviour of the nanoparticles. Arsenic acid enhanced the luminescence intensity whereas arsenious acid quenched the luminescence. This luminescence enhancement or quenching is related with arsenic concentration. This relation of luminescence property with concentration of arsenic can be used to detect arsenic in industrial waste.

  14. Thermodynamic Modeling of Arsenic in Copper Smelting Processes

    Science.gov (United States)

    Chen, Chunlin; Zhang, Ling; Jahanshahi, Sharif

    2010-12-01

    Published data on the activity coefficients of arsenic in liquid copper, matte and, slag have been reviewed, assessed, and used in the development of thermodynamic databases for solution models of melts. The databases were validated against the literature data on the equilibrium distribution of arsenic between the matte and the slag. The models and databases were used in investigating the effects of matte grade, slag chemistry, SO2 partial pressure, arsenic loading, and temperature on the equilibrium distribution of arsenic between the melts and gas phase during copper smelting and converting. The results obtained show that the continuous smelting processes operates close to equilibrium between condensed phases with most arsenic reporting to the gas phase. A comparison of the batch and continuous converting processes showed a considerable difference with respect to the elimination of the arsenic from condensed phases. These results indicate batch processes to be more efficient in the removal of arsenic through the gas stream.

  15. Arsenic: a beneficial therapeutic poison - a historical overview.

    Science.gov (United States)

    Thomas, Xavier; Troncy, Jacques

    2009-06-01

    Arsenicals have been used since ancient Greek and Roman civilizations and in the Far East as part of traditional Chinese medicine. In Western countries, they became a therapeutic mainstay for various ailments and malignancies in the 19th and early 20th centuries. Fowler's potassium bicarbonate-based solution of arsenic trioxide (As2O3)solution was the main treatment of chronic myeloid leukaemia until the 1930s. After a decline in the use of arsenic during the mid-20th century, arsenic trioxide was reintroduced as an anticancer agent after reports emerged from China of the success of an arsenic trioxide-containing herbal mixture for the treatment of acute promyelocytic leukaemia. Arsenic trioxide was first purified and used in controlled studies in China in the 1970s.Subsequently, randomised clinical trials performed in the United States led to FDA approval of arsenic trioxide in the treatment of patients with relapsed or refractory acute promyelocytic leukaemia.

  16. Method development for arsenic analysis by modification in spectrophotometric technique

    Directory of Open Access Journals (Sweden)

    M. A. Tahir

    2012-01-01

    Full Text Available Arsenic is a non-metallic constituent, present naturally in groundwater due to some minerals and rocks. Arsenic is not geologically uncommon and occurs in natural water as arsenate and arsenite. Additionally, arsenic may occur from industrial discharges or insecticide application. World Health Organization (WHO and Pakistan Standard Quality Control Authority have recommended a permissible limit of 10 ppb for arsenic in drinking water. Arsenic at lower concentrations can be determined in water by using high tech instruments like the Atomic Absorption Spectrometer (hydride generation. Because arsenic concentration at low limits of 1 ppb can not be determined easily with simple spectrophotometric technique, the spectrophotometric technique using silver diethyldithiocarbamate was modified to achieve better results, up to the extent of 1 ppb arsenic concentration.

  17. Induction of Human Squamous Cell-Type Carcinomas by Arsenic

    Directory of Open Access Journals (Sweden)

    Victor D. Martinez

    2011-01-01

    Full Text Available Arsenic is a potent human carcinogen. Around one hundred million people worldwide have potentially been exposed to this metalloid at concentrations considered unsafe. Exposure occurs generally through drinking water from natural geological sources, making it difficult to control this contamination. Arsenic biotransformation is suspected to have a role in arsenic-related health effects ranging from acute toxicities to development of malignancies associated with chronic exposure. It has been demonstrated that arsenic exhibits preference for induction of squamous cell carcinomas in the human, especially skin and lung cancer. Interestingly, keratins emerge as a relevant factor in this arsenic-related squamous cell-type preference. Additionally, both genomic and epigenomic alterations have been associated with arsenic-driven neoplastic process. Some of these aberrations, as well as changes in other factors such as keratins, could explain the association between arsenic and squamous cell carcinomas in humans.

  18. A global health problem caused by arsenic from natural sources

    Energy Technology Data Exchange (ETDEWEB)

    Ng, J.C.; Wang, J.P.; Shraim, A. [University of Queensland, Brisbane, Qld. (Australia). National Research Center for Environmental Toxicology

    2003-09-01

    Arsenic is a carcinogen to both humans and animals. Arsenicals have been associated with cancers of the skin, lung, and bladder. Clinical manifestations of chronic arsenic poisoning include non-cancer end point of hyper- and hypo-pigmentation, keratosis, hypertension, cardiovascular diseases and diabetes. Epidemiological evidence indicates that arsenic concentration exceeding 50 {mu}g l{sup -1} in the drinking water is not public health protective. The current WHO recommended guideline value for arsenic in drinking water is 10 {mu}g l{sup -1}, whereas many developing countries are still having a value of 50 {mu}g 1{sup -1}. It has been estimated that tens of millions of people are at risk exposing to excessive levels of arsenic from both contaminated water and arsenic-bearing coal from natural sources. The global health implication and possible intervention strategies were also discussed in this review article.

  19. Arsenic species and chemistry in groundwater of southeast Michigan

    Science.gov (United States)

    Kim, M.-J.; Nriagu, J.; Haack, S.

    2002-01-01

    Groundwater samples, taken from 73 wells in 10 counties of southeast Michigan in 1997 had arsenic concentrations in the range of 0.5 to 278 ??g/l, the average being 29 ??g/l. About 12% of these wells had arsenic concentrations that exceeded the current USEPA's maximum contaminant level of 50 ??g/l. Most (53-98%) of the arsenic detected was arsenite [As(III)] and other observations supported the arsenic species distribution (low redox potential and DO). In shallow groundwater (15 m), the concentration of arsenic is possibly controlled by reductive dissolution of arsenic-rich iron hydroxide/oxyhydroxide and dissolution of arsenic sulfide minerals. ?? 2002 Elsevier Science Ltd. All rights reserved.

  20. Arsenic in the soils of Zimapán, Mexico.

    Science.gov (United States)

    Ongley, Lois K; Sherman, Leslie; Armienta, Aurora; Concilio, Amy; Salinas, Carrie Ferguson

    2007-02-01

    Arsenic concentrations of 73 soil samples collected in the semi-arid Zimapán Valley range from 4 to 14 700 mg As kg(-1). Soil arsenic concentrations decrease with distance from mines and tailings and slag heaps and exceed 400 mg kg(-1) only within 500 m of these arsenic sources. Soil arsenic concentrations correlate positively with Cu, Pb, and Zn concentrations, suggesting a strong association with ore minerals known to exist in the region. Some As was associated with Fe and Mn oxyhydroxides, this association is less for contaminated than for uncontaminated samples. Very little As was found in the mobile water-soluble or exchangeable fractions. The soils are not arsenic contaminated at depths greater than 100 cm below the surface. Although much of the arsenic in the soils is associated with relatively immobile solid phases, this represents a long-term source of arsenic to the environment.

  1. Biosensors for Inorganic and Organic Arsenicals

    Directory of Open Access Journals (Sweden)

    Jian Chen

    2014-11-01

    Full Text Available Arsenic is a natural environmental contaminant to which humans are routinely exposed and is strongly associated with human health problems, including cancer, cardiovascular and neurological diseases. To date, a number of biosensors for the detection of arsenic involving the coupling of biological engineering and electrochemical techniques has been developed. The properties of whole-cell bacterial or cell-free biosensors are summarized in the present review with emphasis on their sensitivity and selectivity. Their limitations and future challenges are highlighted.

  2. Removal of Arsenic from Drinking Water by Adsorption and Coagulation

    Science.gov (United States)

    Zhang, M.; Sugita, H.; Hara, J.; Takahashi, S.

    2013-12-01

    Removal of arsenic from drinking water has been an important issue worldwide, which has attracted greater attentions in recent years especially for supplying safe drinking water in developing countries. Although many kinds of treatment approaches that are available or applicable both in principle and practice, such as adsorption, coagulation, membrane filtration, ion exchange, biological process, electrocoagulation and so on, the first 2 approaches (i.e., adsorption and coagulation) are most promising due to the low-cost, high-efficiency, simplicity of treating systems, and thus can be practically used in developing countries. In this study, a literature survey on water quality in Bangladesh was performed to understand the ranges of arsenic concentration and pH of groundwater in Bangladesh. A series of tests were then organized and performed to investigate the effects of arsenic concentration, arsenic forms, pH, chemical compositions of the materials used for adsorption and coagulation, particle size distribution and treatment time on quality of treated water. The experimental results obtained in the study illustrated that both adsorption and coagulation can be used to effectively reduce the concentrations of either arsenic (V) or arsenic (III) from the contaminated water. Coagulation of arsenic with a magnesium-based material developed in this study can be very effective to remove arsenic, especially arsenic (V), from contaminated water with a concentration of 10 ppm to an undetectable level of 0.002 ppm by ICP analyses. Compared to arsenic (III), arsenic (V) is easier to be removed. The materials used for adsorption and coagulation in this study can remove arsenic (V) up to 9 mg/g and 6 mg/g, and arsenic (III) up to 4 mg/g and 3 mg/g, respectively, depending on test conditions and compositions of the materials being used. The control of pH during treatment can be a challenging technical issue for developing both adsorbent and coagulant. Keywords: Water Treatment

  3. THE PROMOTION OF INNOVATIVE PRODUCTS

    OpenAIRE

    Alyabedeva, I.

    2012-01-01

    The article aims to consider the issues of the innovative products promotion. Peculiarities of innovative market and its future progress, key factors connected with the promotion of innovative products success are analyzed. Here are also suggested the successful marketing strategies variants of the innovative products promotion.

  4. The promotion of innovative products

    OpenAIRE

    Alyabedeva, I.

    2012-01-01

    The article aims to consider the issues of the innovative products promotion. Peculiarities of innovative market and its future progress, key factors connected with the promotion of innovative products success are analyzed. Here are also suggested the successful marketing strategies variants of the innovative products promotion.

  5. Arsenic speciation in Chinese Herbal Medicines and human health implication for inorganic arsenic.

    Science.gov (United States)

    Liu, Xiao-Juan; Zhao, Quan-Li; Sun, Guo-Xin; Williams, Paul; Lu, Xiu-Jun; Cai, Jing-Zhu; Liu, Wen-Ju

    2013-01-01

    Rice and drinking water are recognized as the dominant sources of arsenic (As) for human intake, while little is known about As accumulation and speciation in Chinese Herbal Medicines (CHMs), which have been available for many hundreds of years for the treatment of diseases in both eastern and western cultures. Inorganic arsenic was the predominant species in all of CHMs samples. The levels of inorganic arsenic in CHMs from fields and markets or pharmacies ranged from 63 to 550 ng/g with a mean of 208 ng/g and 94 to 8683 ng/g with a mean of 1092 ng/g, respectively. The highest concentration was found in the Chrysanthemum from pharmacies. It indicates that the risk of inorganic As in CHMs to human health is higher in medicines from markets or pharmacies than that collected directly from fields. Some CHMs may make a considerable contribution to the human intake of inorganic arsenic.

  6. Outbreak of chronic arsenic poisoning among retired workers from an arsenic mine in Japan.

    Science.gov (United States)

    Ishinishi, N; Kodama, Y; Nobutomo, K; Inamasu, T; Kunitake, E; Suenaga, Y

    1977-01-01

    Retired former workers of Matsuo Arsenic Mine of Miyazaki prefecture in Japan were subjected to extensive medical examination. The number of retired workers subjected to examination were 61 of 208 workers who were engaged in the works of the mine and were tracked down by the work rolls. These workers left the mine more than 15 years prior to the time of the examination. The main works in the mine were classified as mining, dressing of ores, refining, and clerical work. Several findings such as arsenodermatitis, depigmentation, performation of nasal septum, hyposmia, anosmia, and peripheral nervous disturbance attributed to exposure to arsenic were observed in 9 of 21 roasters who often worked in the arsenic kitchen. No characteristic findings of arsenic poisoning, that is, gastrointestinal disturbance, disorder of the cardiovascular system, hematopoietic disorders, or liver disturbance were observed in the retired workers. Another notable finding was that 8 cases diagnosed as pneumoconiosis were found in 18 miners. PMID:908287

  7. Arsenic concentrations, related environmental factors, and the predicted probability of elevated arsenic in groundwater in Pennsylvania

    Science.gov (United States)

    Gross, Eliza L.; Low, Dennis J.

    2013-01-01

    Analytical results for arsenic in water samples from 5,023 wells obtained during 1969–2007 across Pennsylvania were compiled and related to other associated groundwater-quality and environmental factors and used to predict the probability of elevated arsenic concentrations, defined as greater than or equal to 4.0 micrograms per liter (µg/L), in groundwater. Arsenic concentrations of 4.0 µg/L or greater (elevated concentrations) were detected in 18 percent of samples across Pennsylvania; 8 percent of samples had concentrations that equaled or exceeded the U.S. Environmental Protection Agency’s drinking-water maximum contaminant level of 10.0 µg/L. The highest arsenic concentration was 490.0 µg/L.

  8. Impact of agronomic practices on arsenic accumulation and speciation in rice grain.

    Science.gov (United States)

    Ma, Rui; Shen, Jianlin; Wu, Jinshui; Tang, Zhong; Shen, Qirong; Zhao, Fang-Jie

    2014-11-01

    Rice is a major source of dietary arsenic (As). The effects of paddy water management, straw incorporation, the applications of nitrogen fertilizer or organic manure, and the additions of biochar on arsenic accumulation and speciation in rice grain were investigated under field conditions over four cropping seasons in Hunan, China. Treatments that promoted anaerobic conditions in the soil, including continuous flooding and straw incorporation, significantly increased the concentration of As, especially methylated As species, in rice grain, whereas N application rate and biochar additions had little or inconsistent effect. Continuous flooding and straw incorporation also increased the abundance of the arsenite methyltransferase gene arsM in the soil, potentially enhancing As methylation in the soil and the uptake of methylated As by rice plants. Intermittent flooding was an effective method to decrease As accumulation in rice grain.

  9. Whole-house arsenic water treatment provided more effective arsenic exposure reduction than point-of-use water treatment at New Jersey homes with arsenic in well water

    Science.gov (United States)

    Spayd, Steven E.; Robson, Mark G.; Buckley, Brian T.

    2014-01-01

    A comparison of the effectiveness of whole house (point-of-entry) and point-of-use arsenic water treatment systems in reducing arsenic exposure from well water was conducted. The non-randomized observational study recruited 49 subjects having elevated arsenic in their residential home well water in New Jersey. The subjects obtained either point-of-entry or point-of-use arsenic water treatment. Prior ingestion exposure to arsenic in well water was calculated by measuring arsenic concentrations in the well water and obtaining water-use histories for each subject, including years of residence with the current well and amount of water consumed from the well per day. A series of urine samples were collected from the subjects, some starting before water treatment was installed and continuing for at least nine months after treatment had begun. Urine samples were analyzed and speciated for inorganic-related arsenic concentrations. A two-phase clearance of inorganic-related arsenic from urine and the likelihood of a significant body burden from chronic exposure to arsenic in drinking water were identified. After nine months of water treatment the adjusted mean of the urinary inorganic-related arsenic concentrations were significantly lower (p < 0.0005) in the point-of-entry treatment group (2.5 μg/g creatinine) than in the point-of-use treatment group (7.2 μg/g creatinine). The results suggest that whole house arsenic water treatment systems provide a more effective reduction of arsenic exposure from well water than that obtained by point-of-use treatment. PMID:24975493

  10. Preliminary study on the mode of occurrence of arsenic in high arsenic coals from southwest Guizhou Province

    Institute of Scientific and Technical Information of China (English)

    丁振华; 郑宝山; 张杰; H.; E.; Belkin; R.; B.; Finkelman; 赵峰华; 周代兴; 周运书; 陈朝刚

    1999-01-01

    Coal samples from high arsenic coal areas have been analyzed by electron microprobe analyzer ( EMPA) , scanning electron microscopy with an energy dispersive X-ray analyzer (SEM-EDX) , X-ray diffraction analysis (XRD) , low temperature ashing (LTA) , transmission electron microscopy (TEM) , X-ray absorption fine structure (XAFS) , instrument neutron activation analysis (INAA) and wet chemical analysis. Although some As-bearing minerals such as pyrite, arsenopyrite, realgar (?), As-bearing sulfate, and As-bearing clays are found in the high arsenic coals, their contents do not account for the abundance of arsenic in the some coals. Analysis of the coal indicates that arsenic exists mainly in the form of As5+ and As3+ , combined with compounds in the organic matrix. The occurrence of such exceptionally high arsenic contents in coal and the fact that the arsenic is dominantly organically associated are unique observations. The modes of occurrence of arsenic in high As-coals are discussed.

  11. Arsenic efflux governed by the arsenic resistance determinant of Staphylococcus aureus plasmid pI258.

    OpenAIRE

    Bröer, S; Ji, G.; Bröer, A; Silver, S

    1993-01-01

    The arsenic resistance operon of Staphylococcus aureus plasmid pI258 determined lowered net cellular uptake of 73As by an active efflux mechanism. Arsenite was exported from the cells; intracellular arsenate was first reduced to arsenite and then transported out of the cells. Resistant cells showed lower accumulation of 73As originating from both arsenate and arsenite. Active efflux from cells loaded with arsenite required the presence of the plasmid-determined arsB gene. Efflux of arsenic or...

  12. Hair and toenail arsenic concentrations of residents living in areas with high environmental arsenic concentrations.

    OpenAIRE

    Hinwood, Andrea L; Sim, Malcolm R; Jolley, Damien; de Klerk, Nick; Bastone, Elisa B; Gerostamoulos, Jim; Drummer, Olaf H

    2003-01-01

    Surface soil and groundwater in Australia have been found to contain high concentrations of arsenic. The relative importance of long-term human exposure to these sources has not been established. Several studies have investigated long-term exposure to environmental arsenic concentrations using hair and toenails as the measure of exposure. Few have compared the difference in these measures of environmental sources of exposure. In this study we aimed to investigate risk factors for elevated hai...

  13. Influence of irrigation practices on arsenic mobilization: Evidence from isotope composition and Cl/Br ratios in groundwater from Datong Basin, northern China

    Science.gov (United States)

    Xie, Xianjun; Wang, Yanxin; Su, Chunli; Li, Junxia; Li, Mengdi

    2012-03-01

    SummaryEnvironment isotopes (δ18O and δ2H) and Cl/Br ratios in groundwater have been used to trace groundwater recharge and geochemical processes for arsenic contamination in Datong Basin. The arsenic concentrations of groundwater samples ranged from 0.4 to 434.9 μg/L with the average of 51.2 μg/L, which exceeded China's drinking water standard (10 μg/L). All the groundwater samples are plotted on or close to the meteoric water line of the δ18O vs. δ2H plot, indicating their meteoric origin. The relationship between δ18O values and Cl/Br ratios and Cl concentrations demonstrate that leaching and mixing are the dominant processes affecting the distribution of high arsenic groundwater in this area. The observed non-linearity in the trend between δ18O and arsenic concentration is due to combined effects of mixing and leaching. The similarity of the trend in Cl/Br ratios and δ18O values for high arsenic groundwater demonstrate that extensive leaching of irrigation return and salt flushing water flow could be the dominant process driving arsenic mobilization in the groundwater system. Moreover, the long term irrigation practice can cause the drastic change of the biogeochemical and redox condition of in the aquifer system, which in turn promotes the mobilization of arsenic. Therefore, groundwater pumping for irrigation in this area of waterborne endemic arsenic poisoning should be under strict control to protect groundwater quality in this area.

  14. Effects of arsenic on nitrate metabolism in arsenic hyperaccumulating and non-hyperaccumulating ferns

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Nandita [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India); Ma, Lena Q., E-mail: lqma@ufl.ed [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Vu, Joseph C. [Chemistry Research Unit, CMAVE, USDA-ARS, Gainesville, FL 32608-1069 and Agronomy Department, University of Florida, Gainesville, FL 32611-0500 (United States); Raj, Anshita [Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India)

    2009-08-15

    This study investigated the effects of arsenic on the in vitro activities of the enzymes (nitrate reductase and nitrite reductase) involved in nitrate metabolism in the roots, rhizomes, and fronds of four-month old Pteris vittata (arsenic - hyperaccumulator) and Pteris ensiformis (non-arsenic--hyperaccumulator) plants. The arsenic treatments (0, 150, and 300 muM as sodium arsenate) in hydroponics had adverse effects on the root and frond dry weights, and this effect was more evident in P. ensiformis than in P. vittata. Nitrate reductase and nitrite reductase activities of arsenate-treated plants were reduced more in P. ensiformis than in P. vittata. This effect was accompanied by similar decreases in tissue NO{sub 3}{sup -} concentrations. Therefore, this decrease is interpreted as being indirect, i.e., the consequence of the reduced NO{sub 3}{sup -} uptake and translocation in the plants. The study shows the difference in the tolerance level of the two Pteris species with varying sensitivity to arsenic. - Arsenic reduced the activity of nitrate and nitrite reductase more in Pteris ensiformis than Pteris vittata.

  15. Mechanism of arsenic tolerance and bioremoval of arsenic by Acidithiobacilus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Chandra Prabha M N

    2011-08-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 This paper reports the studies on mechanism of arsenic tolerance and bioremoval of arsenic ions (arsenite or arsenate by Acidithiobacillus ferrooxidans. Exposure of cells to arsenic ions resulted in increased cell surface hydrophobicity, decreased electrophoretic mobility and stronger adsorption affinity towards arsenopyrite. The mechanism of tolerance to arsenic ions were specific and could be attributed to the changes in specific protein expression in the outer membrane and cytosolic membrane fractions. Biosorption studies showed decrease in solution arsenic concentration only with ferrous–grown cells indicating that presence of ferric ions in the EPS was necessary for binding or entrapment of arsenic ions in the EPS. Bacterial EPS of ferrous–grown wild cells were able to uptake arsenate ions due to the strong affinity of ferric ions towards arsenate ions. Neither cells nor the ferric ions were capable of precipitating or oxidizing arsenite ions directly. Both arsenate ions and arsenite ions were co–precipitated with ferric ions formed during the growth of the bacteria.  

  16. NO2 inhalation promotes Alzheimer’s disease-like progression: cyclooxygenase-2-derived prostaglandin E2 modulation and monoacylglycerol lipase inhibition-targeted medication

    Science.gov (United States)

    Yan, Wei; Yun, Yang; Ku, Tingting; Li, Guangke; Sang, Nan

    2016-03-01

    Air pollution has been reported to be associated with increased risks of cognitive impairment and neurodegenerative diseases. Because NO2 is a typical primary air pollutant and an important contributor to secondary aerosols, NO2-induced neuronal functional abnormalities have attracted greater attention, but the available experimental evidence, modulating mechanisms, and targeting medications remain ambiguous. In this study, we exposed C57BL/6J and APP/PS1 mice to dynamic NO2 inhalation and found for the first time that NO2 inhalation caused deterioration of spatial learning and memory, aggravated amyloid β42 (Aβ42) accumulation, and promoted pathological abnormalities and cognitive defects related to Alzheimer’s disease (AD). The microarray and bioinformation data showed that the cyclooxygenase-2 (COX-2)-mediated arachidonic acid (AA) metabolism of prostaglandin E2 (PGE2) played a key role in modulating this aggravation. Furthermore, increasing endocannabinoid 2-arachidonoylglycerol (2-AG) by inhibiting monoacylglycerol lipase (MAGL) prevented PGE2 production, neuroinflammation-associated Aβ42 accumulation, and neurodegeneration, indicating a therapeutic target for relieving cognitive impairment caused by NO2 exposure.

  17. Research Progress of Promoting Silage Additives%发酵促进型青贮添加剂的研究进展及其应用现状

    Institute of Scientific and Technical Information of China (English)

    郭盼; 单贵莲; 薛世明; 杨国荣

    2012-01-01

    Silage additives is one of the important measures to improve silage quality. In recent decades, we have done lots of researches in additive in forage silage, and has made a great progress, and become the focus of silage fermation. The type of silage addition is the hotspot in recent years. This paper reviews some type of the silage addition, like the lactic acid bacteria, cellulase enzymes, previously fermented juice and sugar and so on, and point out the research situation, the exiting problems and the future trends.%青贮添加剂是提高青贮饲料品质的重要措施之一。近几十年来,人们对于添加剂在牧草青贮技术中的应用进行了大量的研究,而且取得了重要进展,并成为目前青贮技术发展的重点,其中发酵促进型添加剂是近年来研究的热点。本文对乳酸茵、纤维素酶、绿汁发酵液和糖类等发酵促进型牧草青贮添加剂的研究进行了综述,阐述了研究的现状,指出了存在的问题,并对未来的趋势进行了展望。

  18. TSPY potentiates cell proliferation and tumorigenesis by promoting cell cycle progression in HeLa and NIH3T3 cells

    Directory of Open Access Journals (Sweden)

    Chan Wai-Yee

    2006-06-01

    Full Text Available Abstract Background TSPY is a repeated gene mapped to the critical region harboring the gonadoblastoma locus on the Y chromosome (GBY, the only oncogenic locus on this male-specific chromosome. Elevated levels of TSPY have been observed in gonadoblastoma specimens and a variety of other tumor tissues, including testicular germ cell tumors, prostate cancer, melanoma, and liver cancer. TSPY contains a SET/NAP domain that is present in a family of cyclin B and/or histone binding proteins represented by the oncoprotein SET and the nucleosome assembly protein 1 (NAP1, involved in cell cycle regulation and replication. Methods To determine a possible cellular function for TSPY, we manipulated the TSPY expression in HeLa and NIH3T3 cells using the Tet-off system. Cell proliferation, colony formation assays and tumor growth in nude mice were utilized to determine the TSPY effects on cell growth and tumorigenesis. Cell cycle analysis and cell synchronization techniques were used to determine cell cycle profiles. Microarray and RT-PCR were used to investigate gene expression in TSPY expressing cells. Results Our findings suggest that TSPY expression increases cell proliferation in vitro and tumorigenesis in vivo. Ectopic expression of TSPY results in a smaller population of the host cells in the G2/M phase of the cell cycle. Using cell synchronization techniques, we show that TSPY is capable of mediating a rapid transition of the cells through the G2/M phase. Microarray analysis demonstrates that numerous genes involved in the cell cycle and apoptosis are affected by TSPY expression in the HeLa cells. Conclusion These data, taken together, have provided important insights on the probable functions of TSPY in cell cycle progression, cell proliferation, and tumorigenesis.

  19. NPM-ALK oncogenic kinase promotes cell-cycle progression through activation of JNK/cJun signaling in anaplastic large-cell lymphoma.

    Science.gov (United States)

    Leventaki, Vasiliki; Drakos, Elias; Medeiros, L Jeffrey; Lim, Megan S; Elenitoba-Johnson, Kojo S; Claret, Francois X; Rassidakis, George Z

    2007-09-01

    Anaplastic large-cell lymphoma (ALCL) frequently carries the t(2;5)(p23;q35), resulting in aberrant expression of nucleophosmin-anaplastic lymphoma kinase (NPM-ALK). We show that in 293T and Jurkat cells, forced expression of active NPM-ALK, but not kinase-dead mutant NPM-ALK (210K>R), induced JNK and cJun phosphorylation, and this was linked to a dramatic increase in AP-1 transcriptional activity