Arsenic round the world: a review.

Arsenic toxicity and potential mechanisms of action

Arsenic (As) is a toxic metalloid element that is present in air, water and soil. Inorganic arsenic tends to be more toxic than organic arsenic. Examples of methylated organic arsenicals include monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)]. Reactive oxygen species (ROS)-mediated oxidative damage is a common denominator in arsenic pathogenesis. In addition, arsenic induces morphological changes in the integrity of mitochondria. Cascade mechanisms of free radical formation derived from the superoxide radical, combined with glutathione-depleting agents, increase the sensitivity of cells to arsenic toxicity. When both humans and animals are exposed to arsenic, they experience an increased formation of ROS/RNS, including peroxyl radicals (ROO•), the superoxide radical, singlet oxygen, hydroxyl radical (OH•) via the Fenton reaction, hydrogen peroxide, the dimethylarsenic radical, the dimethylarsenic peroxyl radical and/or oxidant-induced DNA damage. Arsenic induces the formation of oxidized lipids which in turn generate several bioactive molecules (ROS, peroxides and isoprostanes), of which aldehydes [malondialdehyde (MDA) and 4-hydroxy-nonenal (HNE)] are the major end products. This review discusses aspects of chronic and acute exposures of arsenic in the etiology of cancer, cardiovascular disease (hypertension and atherosclerosis), neurological disorders, gastrointestinal disturbances, liver disease and renal disease, reproductive health effects, dermal changes and other health disorders. The role of antioxidant defence systems against arsenic toxicity is also discussed. Consideration is given to the role of vitamin C (ascorbic acid), vitamin E (α-tocopherol), curcumin, glutathione and antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase in their protective roles against arsenic-induced oxidative stress.

/pdf/arsenic-toxicity-oxidative-stress-and-human-disease-2lp5eu82d7.pdf

Arsenic: toxicity, oxidative stress and human disease.

Toxicological profile for arsenic

Mercury is a toxic heavy metal which is widely dispersed in nature. Most human exposure results from fish consumption or dental amalgam. Mercury occurs in several chemical forms, with complex pharmacokinetics. Mercury is capable of inducing a wide range of clinical presentations. Diagnosis of mercury toxicity can be challenging but can be obtained with reasonable reliability. Effective therapies for clinical toxicity have been described.

/pdf/mercury-toxicity-and-treatment-a-review-of-the-literature-17h00vn7vh.pdf

Mercury Toxicity and Treatment: A Review of the Literature

DMPS-arsenic challenge test. II. Modulation of arsenic species, including monomethylarsonous acid (MMAIII), excreted in human urine.

Recruitment and retention of women has been a persistent problem in the field of computer science. With a growing number of jobs that require a computer science degree, this problem does not only affect computer science departments with low enrollment, but also impacts industry. There is still no universally accepted explanation for the underrepresentation of women in the computing field. Various solutions have been implemented in an attempt to resolve this problem and yet gender imbalance in fields related to computer science persists.In this paper we study how perceptions held by students influence their intention to pursue computer science. Through a descriptive study, using a survey given out to first semester students in a computer science class, we measure perceptions, attitudes, self-efficacy, and identity, then we study the correlations between them and students' intentions to further pursue computer science. Our goal is to understand how determinative these constructs are to having students continue in the major.Interestingly, self-perception, in terms of self-efficacy (does the student feel they are able to use computer science techniques to solve a problem) and identity (does the student see themselves as a computer scientist), emerged as the primary driver for differences in intention. Many other aspects turned out not to exhibit statistically significant gender differences. Understanding at a detailed level what factors influence students to pursue computer science is critical in devising effective interventions that may increase participation in computer science.

https://www.cs.arizona.edu/~rts/pubs/SIGCSE15.pdf

Allison Titcomb

Papers

DMPS-arsenic challenge test. II. Modulation of arsenic species, including monomethylarsonous acid (MMAIII), excreted in human urine.

The Emerging Role of Self-Perception in Student Intentions