Search results for " Selenium"

Untargeted Metabolomics Investigation on Selenite Reduction to Elemental Selenium by Bacillus mycoides SeITE01

2021

Bacillus mycoides SeITE01 is an environmental isolate that transforms the oxyanion selenite (SeO32−) into the less bioavailable elemental selenium (Se0) forming biogenic selenium nanoparticles (Bio-SeNPs). In the present study, the reduction of sodium selenite (Na2SeO3) by SeITE01 strain and the effect of SeO32− exposure on the bacterial cells was examined through untargeted metabolomics. A time-course approach was used to monitor both cell pellet and cell free spent medium (referred as intracellular and extracellular, respectively) metabolites in SeITE01 cells treated or not with SeO32−. The results show substantial biochemical changes in SeITE01 cells when exposed to SeO32−. The initial u…

Tunable photoluminescence properties of selenium nanoparticles: biogenic versus chemogenic synthesis

2020

Abstract Various technological and biomedical applications rely on the ability of materials to emit light (photoluminescence [PL]), and, among them, metal nanoparticles (NPs) and semi-conductor Quantum Dots (QDs) represent ideal candidates as sensing probes and imaging tools, portraying better PL features than conventional organic dyes. However, the knowledge of PL behavior of semiconductor NPs – i.e., selenium; SeNPs – is still in its infancy, especially for those synthesized by microorganisms. Considering the essential role played by biogenic SeNPs as antimicrobial, anticancer, and antioxidant agents, or food supplements, their PL properties must be explored to take full advantage of them…

Development of quadrupole collectivity in the neutron-rich Ni, Zn, Ge, and Se isotopes

2003

An experiment was performed to study the collective properties of neutron-rich Ni, Zn, Ge, and Se isotopes. Of particular interest is the vicinity of the N = 50 and Z = 28 shell closures. For most neutron-rich nuclei in this region of the chart of nuclei the B(E2) values of the transitions from the ground to the first excited 2+ states are unknown. This information would give valuable insight into the changes in nuclear structure when going to more neutron-rich nuclei.

The reduction of selenium(IV) by boreal Pseudomonas sp. strain T5-6-I – Effects on selenium(IV) uptake in Brassica oleracea

2019

Selenium (Se) is an essential micronutrient but toxic when taken in excessive amounts. Therefore, understanding the metabolic processes related to selenium uptake and bacteria-plant interactions coupled with selenium metabolism are of high importance. We cultivated Brassica oleracea with the previously isolated heterotrophic aerobic Se(IV)-reducing Pseudomonas sp. T5-6-I strain to better understand the phenomena of bacteria-mediated Se(IV) reduction on selenium availability to the plants. B. oleracea grown on Murashige and Skoog medium (MS-salt agar) with and without of Pseudomonas sp. were amended with Se(IV)/75Se(IV), and selenium transfer into plants was studied using autoradiography and…

Antioxidants: Role in the prevention and treatment of bronchopulmonary dysplasia

2022

Bronchopulmonary dysplasia (BPD) is one of the major causes of chronic respiratory diseases among infants. Both pharmacological and nonpharmacological approaches have been proposed for its management. Since oxidative stress is known to play a pivotal role in the pathogenesis of BPD, it is reasonable to consider the potential of antioxidant strategies in the prevention and treatment of this condition. Indeed, antioxidants can prevent or inhibit substrate oxidation. Some studies have evaluated the efficacy of the exogenous administration of vitamins and micronutrients in reducing the propagation of free radicals through their scavenging capacity. Nonetheless, encouraging preclinical results d…

Electrochemical deposition of different semiconductors for application in solar cells

2011

Influence of bacterial physiology on processing of selenite, biogenesis of nanomaterials and their thermodynamic stability

2019

We explored how Ochrobactrum sp. MPV1 can convert up to 2.5 mM selenite within 120 h, surviving the challenge posed by high oxyanion concentrations. The data show that thiol-based biotic chemical reaction(s) occur upon bacterial exposure to low selenite concentrations, whereas enzymatic systems account for oxyanion removal when 2 mM oxyanion is exceeded. The selenite bioprocessing produces selenium nanomaterials, whose size and morphology depend on the bacterial physiology. Selenium nanoparticles were always produced by MPV1 cells, featuring an average diameter ranging between 90 and 140 nm, which we conclude constitutes the thermodynamic stability range for these nanostructures. Alternativ…

The 2016 European Thyroid Association/European Group on Graves' Orbitopathy Guidelines for the Management of Graves' Orbitopathy

2015

Graves' orbitopathy (GO) is the main extrathyroidal manifestation of Graves' disease, though severe forms are rare. Management of GO is often suboptimal, largely because available treatments do not target pathogenic mech anisms of the disease. Treatment should rely on a thorough assessment of the activity and severity of GO and its impact on the patient's quality of life. Local measures (artificial tears, ointments and dark glasses) and control of risk factors for progression (smoking and thyroid dysfunction) are recommended for all patients. In mild GO, a watchful strategy is usually sufficient, but a 6-month course of selenium supplementation is effective in improving mild manifestations …

Serenoa repens, lycopene and selenium versus tamsulosin for the treatment of LUTS/BPH. An Italian multicenter double-blinded randomized study between…

2014

Selenium around Etna Volcano, Italy

2010

Humans are attracted by the fertile properties of volcanic soils and currently around 10% of the world population lives within active volcanic areas. Volcanoes emit significantly amounts of potentially toxic elements such as selenium (Se), even in the absence of obvious volcanic activity. Although Se is an essential element for humans, ingestion of an excess amount of Se can produce adverse effects. Mt. Etna, the biggest volcano in Europe, is persistently active for the last 200,000 years and one of the most intensely monitored volcanoes. We have studied selenium in rainwater and soils from Mt Etna volcano. Bulk depositions were collected from April 2006 to December 2007, using a network of…