Search results for " arsenic"

Some aspects of the solid state physics of yellow arsenic

1996

Biology and management of therapy-related acute promyelocytic leukemia.

2013

Therapy-related acute promyelocytic leukemia (t-APL) has been increasingly reported after exposure to cytotoxic and/or immunosuppressive agents given for prior malignancies or autoimmune diseases. t-APL represents both a model for better understanding human leukemogenesis and an interesting therapeutic subset which requires specific adaptations for optimal management.We discuss here potential risk factors for t-APL development and the main biologic and clinical characteristics of t-APL as compared to de-novo APL.In addition, we review therapeutic results obtained in patients with t-APL receiving conventional retinoic acid and chemotherapy and discuss new treatment opportunities with minimal…

Atomic fluorescence determination of total and inorganic arsenic species in beer

2001

A simple and nearly direct procedure has been developed for the determination of As in beers, based on hydride generation and atomic fluorescence detection. Using 2 mol l−1 HCl with a carrier flow of 6 ml min−1, 3% m/v NaBH4 with a flow of 1.3 ml min−1, a reaction coil of 200 cm and an argon flow of 400 ml min−1, total arsenic in beer could be determined in samples diluted 1∶10 with a final concentration of 2 mol l−1 HCl, 1% m/v KI and 0.08% v/v of an antifoam agent. For the estimation of AsIII and AsV concentrations in beer samples, the difference between the analytical sensitivities of the fluorescence signals obtained for As hydride, without and with previous treatment of samples with KI…

The symbiosis between Nicotiana tabacum and the endomycorrhizal fungus Funneliformis mosseae increases the plant glutathione level and decreases leaf…

2015

Over time, anthropogenic activities have led to severe cadmium (Cd) and arsenic (As) pollution in several environments. Plants inhabiting metal(loid)-contaminated areas should be able to sequester and detoxify these toxic elements as soon as they enter roots and leaves. We postulated here that an important role in protecting plants from excessive metal(loid) accumulation and toxicity might be played by arbuscular mycorrhizal (AM) fungi. In fact, human exploitation of plant material derived from Cd- and As-polluted environments may lead to a noxious intake of these toxic elements; in particular, a possible source of Cd and As for humans is given by cigarette and cigar smoke. We investigated …

Inorganic arsenic species in groundwater: A case study from Purbasthali (Burdwan), India

1996

A regional groundwater quality survey from 20 tube wells in the Purbasthali area of the Burdwan district of West Bengal province (India) identified arsenic pollution in this area. Arsenic was detected in 19 cases at a concentration level 0.5 to 135.9 micrograms/L. Speciation studies indicate that As(III) is present in only one sample and organo-arsenic compounds have not been detected. Iron, antimony and pH of such water samples were also studied to see if there is any correlation of the presence of arsenic and these parameters. A high concentration of iron (0.3 to 10.7 mg/L) has been detected. Antimony is present in all these water samples (0.03 to 0.9 microgram/L). The pH value of the gro…

Biological effects of inorganic arsenic on primary cultures of rat astrocytes

2010

It is well established that inorganic arsenic induces neurotoxic effects and neurological defects in humans and laboratory animals. The cellular and molecular mechanisms of its actions, however, remain elusive. Herein we report the effects of arsenite (NaAsO2) on primary cultures of rat astrocytes. Cells underwent induction of heat shock protein 70 only at the highest doses of inorganic arsenic (30 and 60 microM), suggesting a high threshold to respond to stress. We also investigated arsenic genotoxicity with the comet assay. Interestingly, although cells treated with 10 microM arsenite for 24 h maintained >70% viability, with respect to untreated cells, high DNA damage was already observed…

Arsenic-induced DNA hypomethylation affects chromosomal instability in mammalian cells

2004

Early genetic instability induced in dividing V79-Cl3 Chinese hamster cells by inorganic arsenic, as demonstrated in our previous investigation, was evidenced by aneuploidy and nuclear abnormalities, but not by chromosomal rearrangements. Here we report the results of cytogenetic and morphological analyses performed on the progeny of cells dividing at the end of sodium arsenite treatment after they had been expanded through 120 generations (ASO cells) and then cloned. The acquired genetic instability persisted and was increased by highly unstable chromosomal rearrangements, namely dicentric chromosomes and telomeric associations, which were not seen following acute exposure. A peculiar find…

Cobre para los muertos. Estudio arqueométrico del material metálico procedente del monumento megalítico prehistórico de Castillejo del Bonete (Terrin…

2014

Castillejo del Bonete es una cueva que fue utilizada y adaptada como monumento funerario durante la Prehistoria reciente. Abundantes piezas metálicas en óptimo estado de conservación se han recuperado de los túmulos construidos encima de la cueva, tanto en el interior de tumbas como fuera de ellas. El objetivo de este trabajo es presentar la colección metálica del yacimiento recuperada hasta finales de 2012. También el estudio arqueometalúrgico de varias de las piezas y una interpretación del conjunto en relación a su ámbito cultural y territorial. La investigación además incorpora datos inéditos de El Acequión, Albacete, para proporcionar una perspectiva comparativa sobre la procedencia de…

Le linee cellulari V79 e Caco-2: due modelli per studi in vitro di epi-mutagenesi

2020

È da pochi anni noto che alcune sostanze, non classificabili come veri e propri mutageni, sono in realtà dei modulatori epigenetici ed inducono cambiamenti nella metilazione del DNA, nella acetilazione/deacetilazione degli istoni e possono modificare la sintesi endocellulare di alcuni miRNA. Inducendo modificazioni epigenetiche non causano mutazioni genetiche, sfuggono ai test di mutagenesi e carcinogenesi fino ad ora utilizzati ma possono ugualmente avere effetti fenotipici simili a quelli di un mutageno/carcinogeno. Per anni l’arsenico, noto veleno ad alte dosi, contaminante obbligato delle acque potabili, è stato oggetto di dibattiti sulla sua mutagenicità a basse dosi. Utilizzato, parad…

Arsenic trioxide-based therapy of relapsed acute promyelocytic leukemia: registry results from the European LeukemiaNet

2015

In 2008, a European registry of relapsed acute promyelocytic leukemia was established by the European LeukemiaNet. Outcome data were available for 155 patients treated with arsenic trioxide in first relapse. In hematological relapse (n=104), 91% of the patients entered complete hematological remission (CR), 7% had induction death and 2% resistance, 27% developed differentiation syndrome and 39% leukocytosis, whereas no death or side effects occurred in patients treated in molecular relapse (n=40). The rate of molecular (m)CR was 74% in hematological and 62% in molecular relapse (P=0.3). All patients with extramedullary relapse (n=11) entered clinical and mCR. After 3.2 years median follow-u…