Homocysteine treatment alters redox capacity of both endothelial and tumor cells

Homocysteine is a non-proteinogenic amino acid playing key roles in two interconnected metabolic pathways, namely, the activated methyl cycle and the linear trans-sulfuration pathway that allows the conversion of methionine to cysteine. A dysregulation of intracellular homocysteine metabolism could yield an increased export of this amino acid, leading to hyperhomocysteinemia, which has been associated with an increased risk of cardiovascular diseases. In spite of decades of experimental effort, there is no definitive consensus on what could be the molecular mechanisms whereby hyperhomocysteinemia could contribute to cardiovascular disease. The redox active nature of homocysteine has favored the idea of an induction of oxidative stress as the underlying mechanism of homocysteine toxicity. In contrast, homocysteine can also behave as an anti-oxidant. The present work is aimed to further analyze the capacity of homocysteine to modulate the redox capacity of both endothelial and tumor cells. [Our experimental work is supported by grants BIO2014-56092-R (MINECO and FEDER) and P12-CTS-1507 (Andalusian Government and FEDER) and funds from group BIO-267 (Andalusian Government). The "CIBER de Enfermedades Raras" is an initiative from the ISCIII (Spain)].Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Trace metal levels and toxicity in the Huelva Estuary (Spain): A case study with comparisons to historical levels from the past decades

The Huelva Estuary, in the south of Spain, is a highly polluted area subject to heavy anthropogenic pressures such as coastal urbanization, fishing and tourism activities, commercial transports, as well as petrochemical, agrichemical and intense mining industry. Trace metal levels in sediments from the Huelva Estuary have been largely investigated over the last decades, but an evaluation through the years has not been considered yet. This study analyzed the current concentrations for Cr, Cu, Mn, Ni, Pb, Zn, Fe and organic matter content in sediments from two sampling sites (Muelle Capesa and Mazagón) and toxicity on fertilization and embryogenesis of sea urchin (Paracentrotus lividus). Results were compared with data from the past decades. Zn and Cu displayed higher levels and enrichment in sediments from the Muelle Capesa close to the Huelva industrial area. Mazagón sediment, despite moderate levels and enrichment in Zn and Cu, is proved to be affected by anthropogenic impacts, due to continuous inputs from acid mine drainage and alongshore current transport. In our experiments, sea urchin fertilization rates and larval development were significantly affected by exposure to elutriates from Huelva Estuary sediments. Therefore, the Huelva Estuary area shows a declining but chronic contamination in Zn and Cu, originating from point and diffused anthropic activities, which in turn, are likely to cause adverse effects on the coastal ecosystem. Keywords: Trace metals, Sediment, Paracentrotus lividus bioassay, Huelva Estuary, Toxicit

One-year client impacts of quality of care improvements achieved in Peru

This report presents a one-year assessment of quality-of-care improvements in Peru, following provider training on the job aids–assisted Balanced Counseling Strategy. Results showed significant enhancement of quality of care, an increase in session length, and improved client knowledge of the method chosen when this was an IUD or hormonal method. Correlational findings suggested that better impacts can be achieved in provincial primary health facilities than in larger settings like clinics or hospitals in capital cities. The results are important because: 1) other studies have failed to show significant impacts of controlled quality-of-care improvements on the use of contraception; and 2) the Balanced Counseling Strategy was not implemented to its full extent. Greater impacts can be expected when the Strategy’s potential is fully realized

Diabetes changes ionotropic glutamate receptor subunit expression level in the human retina

Early diabetic retinopathy is characterized by changes in subtle visual functions such as contrast sensitivity and dark adaptation. The outcome of several studies suggests that glutamate is involved in retinal neurodegeneration during diabetes. We hypothesized that the protein levels of ionotropic glutamate receptor subunits are altered in the retina during diabetes. Therefore, we investigated whether human diabetic patients have altered immunoreactivity of ionotropic glutamate receptor subunits in the retina.http://www.sciencedirect.com/science/article/B6SYR-4RS9SS1-1/1/232d6ae7147919a2286326863ee69f1

Sweet Stress: Coping With Vascular Dysfunction in Diabetic Retinopathy

Oxidative stress plays key roles in the pathogenesis of retinal diseases, such as diabetic retinopathy. Reactive oxygen species (ROS) are increased in the retina in diabetes and the antioxidant defense system is also compromised. Increased ROS stimulate the release of pro-inflammatory cytokines, promoting a chronic low-grade inflammation involving various signaling pathways. An excessive production of ROS can lead to retinal endothelial cell injury, increased microvascular permeability, and recruitment of inflammatory cells at the site of inflammation. Recent studies have started unraveling the complex crosstalk between retinal endothelial cells and neuroglial cells or leukocytes, via both cell-to-cell contact and secretion of cytokines. This crosstalk is essential for the maintenance of the integrity of retinal vascular structure. Under diabetic conditions, an aberrant interaction between endothelial cells and other resident cells of the retina or invading inflammatory cells takes place in the retina. Impairment in the secretion and flow of molecular signals between different cells can compromise the retinal vascular architecture and trigger angiogenesis. In this review, the synergistic contributions of redox-inflammatory processes for endothelial dysfunction in diabetic retinopathy will be examined, with particular attention paid to endothelial cell communication with other retinal cells

New Brazilian pineapple leaf fibers for textile application: cottonization and dyeing performance

This work evaluates the dyeing performance associated with a cottonization and bleaching pretreatment of pineapple leaf fibers from two diferent species from Brazil: curaua (A. lucidus syn. A. erectifolius) and red pineapple (A. bracteatus (Lindl.) Schult. & Schult.f), aiming its application in textile materials for garments. Treated and untreated fibers were compared for their morphological, chemical, physical and color properties. The fibers underwent changes in their chemical and physical structural characteristics after pretreatment. The results of SEM, FTIR and whiteness index analysis indicated that the cottonization process improved the color and surface uniformity of fibers, reducing non-cellulosic matters, such as lignin and pectin. Treated fibers also presented low impurities content, i.e., oils, wax and fats (between 1.1 and 2.1%). However, compared to untreated fibers, treated curaua show an increase in impurities, supposedly caused by the removal of epidermal tissue from the fiber surface, which became the fiber bundle structure more accessible. Cottonization process also produced thinner, individualized and more resistant fiber bundles, which was evidenced by a decrease in linear density by 30 and 42% and an increase in tenacity by 12 and 23%. The dyeing behavior of fibers was investigated using blue, red and yellow reactive dyes. Fibers of both species demonstrated good dyeing behavior, with K/S values compatible with textile application standards (between 4 and 11) and an excellent color fastness to laundering.This work is also supported by FEDER funds through the Competitivity Factors Operational Programme-COMPETE and by national funds through FCT-Foundation for Science and Technology within the scope of the project POCI-01-0145-FEDER-007136

Elevated glucose changes the expression of ionotropic glutamate receptor subunits and impairs calcium homeostasis in retinal neural cells

PURPOSE. Altered glutamatergic neurotransmission and calcium homeostasis may contribute to retinal neural cell dysfunction and apoptosis in diabetic retinopathy (DR). The purpose of this study was to determine the effect of high glucose on the protein content of -amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) and kainate glutamate receptor subunits, particularly the GluR2 subunit, because it controls Ca2 permeability of AMPA receptor-associated channels. The effect of high glucose on the concentration of cytosolic free calcium ([Ca2 ]i) was also investigated. METHODS. The protein content of GluR1, GluR2, GluR6/7, and KA2 subunits was assessed by Western blot. Cobalt staining was used to identify cells containing calcium/cobalt-permeable AMPA receptors. The [Ca2 ]i changes evoked by KCl or kainate were recorded by live-cell confocal microscopy in R28 cells and in primary cultures of rat retina, loaded with fluo-4. RESULTS. In primary cultures, high glucose significantly decreased the protein content of GluR1 and GluR6/7 subunits and increased the protein content of GluR2 and KA2 subunits. High glucose decreased the number of cobalt-positive cells, suggesting a decrease in calcium permeability through AMPA receptor-associated channels. In high-glucose–treated cells, changes in [Ca2 ]i were greater than in control cells, and the recovery to basal levels was delayed. However, in the absence of Na , to prevent the activation of voltage-sensitive calcium channels, the [Ca2 ]i changes evoked by kainate in the presence of cyclothiazide, which inhibits AMPA receptor desensitization, were significantly lower in high-glucose–treated cells than in control cultures, further indicating that AMPA receptors were less permeable to calcium. Mannitol, used as an osmotic control, did not cause significant changes compared with the control. CONCLUSIONS. The results suggest that elevated glucose may alter glutamate neurotransmission and calcium homeostasis in the retina, which may have implications for the mechanisms of vision loss in DR.Foundation for Science and Technology, Portugal and FEDER (Grant POCTI/CBO/38545/01), The Juvenile Diabetes Research Foundation, The American Diabetes Association and the Pennsylvania Lions Sight Conservation and Eye Eye Research Foundation

Current status of bacterial spot of stone fruits and almond caused by Xanthomonas arboricola pv. pruni in Spain

In 2002, typical symptoms of bacterial spot disease of stone fruits caused by Xanthomomas arboricola pv. pruni (Xap) were observed for the first time on Japanese plum in Badajoz (south-western Spain). During the following years, the pathogen was found in seven other eastern and northern Spanish provinces (Valencia, Alicante, Zaragoza, Huesca, Navarra, Lérida and Mallorca) affecting different cultivars of Japanese plum, nectarine, peach and almond. There are few previous reports of Xap on almond, the Spanish outbreaks constituting its first detection on this host in the European Union (EU). Identification of the pathogen was performed using biochemical tests, fatty acid methyl esters (FAME) profiles, conventional and real-time PCR, and hypersensitivity reaction on tobacco leaves. Pathogenicity was demonstrated by inoculation of young potted plants of peach, plum or almond and successful re-isolations from plants with symptoms. In areas where infected plants were found, eradication programs were set up since Xap has a quarantine status according to phytosanitary EU legislation.Publishe

Climatic and lacustrine morphometric controls of diatom paleoproductivity in a tropical Andean lake

15 páginas, 6 figuras, 1 tablaThe coupling of lake dynamics with catchment biogeochemistry is considered the key element controlling primary production in mountain lakes at time scales of a few decades to millennia, yet little is known on the impacts of the morphometry of lakes throughout their ontogeny. As Lake Chungará (Central Andean Altiplano, northern Chile) experienced long-term lake-level fluctuations that strongly modified its area:volume ratio, it is an ideal system for exploring the relative roles that long-term climatic shifts and lake morphometry play on biosiliceous lacustrine productivity. In this paper, we review previous data on the percent contents of total organic carbon, total inorganic carbon, total nitrogen, total biogenic silica, isotopic composition of organic matter, carbonates, and diatom frustules, as well as data on the abundance of the chlorophycean Botryococcus braunii in this lake for the period 12,400–1300 cal yr BP. We also include new data on organic carbon and biogenic silica mass accumulation rates and the diatom assemblage composition of an offshore core dated using 14C and U/Th. Biosiliceous productivity in Lake Chungará was influenced by shifts in allochthonous nutrient inputs related to variability in precipitation. Humid phases dated at approx. 12,400 to 10,000 and 9600 to 7400 cal yr BP coincide with periods of elevated productivity, whereas decreases in productivity were recorded during arid phases dated at approx. 10,000 to 9600 and 7400 to 3550 cal yr BP (Andean mid-Holocene Aridity Period). However, morphometry-related in–lake controls led to a lack of a linear response of productivity to precipitation variability. During the late Glacial to early Holocene, lowstands facilitated complete water column mixing, prompting episodic massive blooms of a large centric diatom, Cyclostephanos cf. andinus. Thus, moderate productivity could be maintained, regardless of aridity, by this phenomenon of morphometric eutrophy during the early history of the lake. The subsequent net increase in lake level introduced modifications in the area of the epilimnion sediments versus the total volume of the epilimnion, preventing complete overturn. Surpassing a certain depth threshold at approx. 8300 cal yr BP caused cessation of the morphometric eutrophy conditions associated with Cyclostephanos cf. andinus superblooms. After 7300 cal yr BP, the lake experienced a decrease in biosiliceous productivity and a change of state that involved a stronger dependence on precipitation variability, with a lesser contribution of diatoms to the total primary productivity. Our results show that the interpretation of lacustrine paleoproductivity records as paleoclimatic archives needs to take into account the effects of changes in the epilimnion sediment area to epilimnion volume ratio in association with lake ontogenyThe Spanish Ministry of Science and Innovation funded this research through the projects ANDESTER (BTE2001-3225), Complementary Action (BTE2001-5257-E), LAVOLTER (CGL2004-00683/BTE), GEOBILA (CGL2007-60932/BTE) and CONSOLIDER-Ingenio 2010 GRACCIE (CSD2007-00067)Peer reviewe