PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “ARSENIC AND COMPOUNDS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 577 records · Page 32Linked to original sources

Resonant tunneling in nanocolumns improved by quantum collimation.

We report on a quantum collimation effect based on surface depletion regions in AlAs/GaAs nanocolumns with an embedded resonant tunneling structure. The considered MBE-grown nanodevices have been fabricated by means of a top-down approach that employs a reproducible lithographic definition of the vertical nanocolumns. By analyzing the scaling properties of these nanodevices, we discuss how a collimation effect due to a saddle point in the confining potential can explain an improved device performance of the ultimately scaled structures at room temperature.

Aluminum Compounds↗

Occupation and larynx and hypopharynx cancer: a job-exposure matrix approach in an international case-control study in France, Italy, Spain and Switzerland.

OBJECTIVE: To investigate the effect of exposure to occupational agents on the risk of hypopharyngeal/laryngeal cancer. METHODS: Case-control study conducted during 1979-1982 in six centres in South Europe. An occupational history and information on exposure to non-occupational factors were collected for 1010 male cases of hypopharyngeal/ laryngeal cancer as well as for 2176 population controls. The exposure to 10 occupational agents was assessed through a job-exposure matrix. As occupational histories had been collected since 1945 major analyses were restricted to subjects aged less than 55 years (315 cases and 819 controls). RESULTS: Significant elevated risks adjusted for non-occupational variables (smoking, alcohol consumption and diet) and other occupational exposures were consistently found for organic solvents (odds ratio (OR) for ever-exposure: 1.7, 95% confidence interval: 1.1-2.5) and asbestos (OR: 1.6, 1.0-2.5). A significant positive trend for both probability of exposure and duration was found for exposure to solvents. A positive association between exposure to formaldehyde and laryngeal cancer was also suggested. No association was found for exposure to arsenic and compounds, chromium and compounds, and polycyclic aromatic hydrocarbons. Analyses restricted to subjects aged 55 or more did not show elevated risks, with the exception of wood dust (OR: 1.8, 1.3-2.7). CONCLUSIONS: In our study occupational exposure to solvents was associated with an increased risk of hypopharyngeal/laryngeal cancer. Results also provide additional evidence of an excess of risk for exposure to asbestos.

Adult↗

Acute promyelocytic leukemia: PML/RARalpha and the leukemic stem cell.

Acute promyelocytic leukemia (APL) is distinguished from other acute myeloid leukemias (AMLs) by cytogenetic, clinical, as well as biological characteristics. The hallmark of APL is the t(15;17), which leads to the expression of the PML/RARalpha fusion protein. PML/RARalpha is the central leukemia-inducing lesion in APL and is directly targeted by all trans retinoic acid (t-RA) as well as by arsenic, both compounds able to induce complete remissions. This review focuses on potential stem cell involvement in APL outlining the knowledge about the APL-initiating stem cell and the influence of PML/RARalpha on the biology of the hematopoietic stem cell. Moreover, the importance of the blockage of t-RA signaling by the PML/RARalpha for the pathogenesis of APL is discussed, taking the relevance of the t-RA signaling pathway for the global hematopoiesis into account.

Apoptosis↗

A novel zirconium polyoxometalate compound: (NH(4))(9)[Zr(2)(mu-OH)(H(2)O)(2)(AsOH)(2)(AsW(7)O(28))(AsW(10)O(36))].26H(2)O.

The crystal structure of the title compound, nonaammonium (arsenic decatungstido)(arsenic heptatungstido)diaqua-mu-hydroxo-(hydroxyarsenido)dizirconium hexacosahydrate, which was obtained from the reaction of [NaAs(4)W(40)O(140)](27-) with Zr(IV), has been determined. The anionic complex consists of two hydroxyl-bridged seven-coordinate capped trigonal-prismatic zirconium ions, which are bonded to an [AsW(10)O(36)](9-) anion and to an [AsW(7)O(28)](11-) anion that has two [AsOH](2+) capping units. The asymmetric unit contains half of the complex, with one crystallographically independent Zr atom. Crystallographic m symmetry imposed by the monoclinic C2/m space group gives rise to the asymmetric unit comprising half of the complex with one crystallographically independent Zr atom.

Journal Article↗

Properties of IncP-2 plasmids of Pseudomonas spp.

Thirty IncP-2 R plasmids from isolates of Pseudomonas spp. of diverse geographical origins were examined for the production of resistance properties. All the plasmids determined resistance to tellurite and all inhibited the propagation of certain DNA phages, although several patterns of phage inhibition were detected. Of the 30 plasmids, 29 determined resistance to streptomycin, 28 determined resistance to mercuric ion, and 24 determined resistance to sulfonamide. Resistance to other antibiotics, to compounds of arsenic, boron, or chromium, and to UV irradiation was less common. The degradative plasmid CAM also belonged to this group. When CAM was introduced into recipients carrying an IncP-2 R plasmid, recombinant plasmids were often formed in which antibiotic resistance and the ability to grow on camphor were transferred together to further recipients or were lost together in a strain in which IncP-2 plasmids were unstable. Such hybrid plasmid formation was rec dependent. CAM and other IncP-2 plasmids that determine UV light resistance demonstrated UV-enhanced, nonpolarized transfer of the Pseudomonas aeruginosa chromosome. By agarose gel electrophoresis, all IncP-2 R plasmids and CAM were ca. 300 X 10(6) in molecular weight.

Conjugation, Genetic↗

Trichuris trichiura infestations in the United Kingdom and treatment with difetarsone.

Stool specimens were examined for the parasite Trichuris trichiura from 1,860 patients in 17 hospitals for the mentally subnormal in the U.K. It was found in 10 of these hospitals, and an overall incidence of 13.2% was recorded. Most cases occurred in the South, where the overall incidence was 36.3%.Difetarsone was used in the treatment of infestations in two hospitals, and proved to be very well tolerated, cure rates of 81 to 88% being obtained.

Adolescent↗

Effect on water resources from upstream water diversion in the Ganges basin.

Bangladesh faces at least 30 upstream water diversion constructions of which Farakka Barrage is the major one. The effects of Farakka Barrage on water resources, socioeconomy, and culture have been investigated downstream in the basins of the Ganges and its distributaries. A diversion of up to 60% of the Ganges water over 25 yr has caused (i) reduction of water in surface water resources, (ii) increased dependence on ground water, (iii) destruction of the breeding and raising grounds for 109 species of Gangetic fishes and other aquatic species and amphibians, (iv) increased malnutrition, (v) deficiency in soil organic matter content, (vi) change in the agricultural practices, (vii) eradication of inland navigable routes, (viii) outbreak of waterborne diseases, (ix) loss of professions, and (x) obstruction to religious observances and pastimes. Further, arsenopyrites buried in the prebarrage water table have come in contact with air and formed water-soluble compounds of arsenic. Inadequate recharging of ground water hinders the natural cleansing of arsenic, and threatens about 75,000,000 lives who are likely to use water contaminated with up to 2 mg/L of arsenic. Furthermore, the depletion of surface water resources has caused environmental heating and cooling effects. Apart from these effects, sudden releases of water by the barrage during the flood season cause devestating floods. In consideration of such a heavy toll for the areas downstream, strict international rules have to be laid down to preserve the riparian ecosystems.

Adult↗