Person-to-Person Transmission of Andes Virus

Epidemiologic and genetic data show that person-to-person spread likely took place during the prodromal phase or shortly after it ended

Leptin Inhibits Angiotensin II-Induced Intracellular Calcium Increase and Vasoconstriction in the Rat Aorta

Besides its role in body weight control leptin may also act as a vasoactive hormone. This study was designed to investigate whether leptin modifies angiotensin II (ANG II)-induced vascular responses. The expression of functional leptin receptors (OB-Rb) was detected in vascular smooth muscle cells (VSMCs) from adult Wistar rats by RT-PCR. Immunocytochemistry and Western blot analysis further showed the expression of OB-R protein in VSMCs. The ANG II (10(-7) mol/liter)-induced increase in intracellular Ca(2+) was blocked (P < 0.01) by leptin (10(-8) mol/liter). Moreover, in calcium-free buffer leptin was able to inhibit 65% of the ANG II-induced calcium release from intracellular stores. In endothelium-denuded aortic rings from adult Wistar rats no effect of leptin on basal tension was observed. However, the ANG II-induced isometric contraction was reduced (P < 0.05) by leptin (10(-8) mol/liter). The experiments were also performed in age- and sex-matched Zucker rats, in which no effect of leptin on ANG II-induced calcium increase and vasoconstriction was observed. It is concluded that leptin blocks the vasoconstrictor action of ANG II and inhibits the ANG II-induced increase in intracellular Ca(2+) in VSMCs through OB-Rb. These findings provide new insight into the physiological effects of leptin on blood pressure regulation

Isolation and characterization of <i>Magnetospirillum</i> sp strain 15-1 as a representative anaerobic toluene-degrader from a constructed wetland model

Previously, Planted Fixed-Bed Reactors (PFRs) have been used to investigate microbial toluene removal in the rhizosphere of constructed wetlands. Aerobic toluene degradation was predominant in these model systems although bulk redox conditions were hypoxic to anoxic. However, culture-independent approaches indicated also that microbes capable of anaerobic toluene degradation were abundant. Therefore, we aimed at isolating anaerobic-toluene degraders from one of these PFRs. From the obtained colonies which consisted of spirilli-shaped bacteria, a strain designated 15-1 was selected for further investigations. Analysis of its 16S rRNA gene revealed greatest similarity (99%) with toluene-degrading Magnetospirillum sp. TS-6. Isolate 15-1 grew with up to 0.5 mM of toluene under nitrate-reducing conditions. Cells reacted to higher concentrations of toluene by an increase in the degree of saturation of their membrane fatty acids. Strain 15-1 contained key genes for the anaerobic degradation of toluene via benzylsuccinate and subsequently the benzoyl-CoA pathway, namely bssA, encoding for the alpha subunit of benzylsuccinate synthase, bcrC for subunit C of benzoyl-CoA reductase and bamA for 6-oxocyclohex-1-ene-1-carbonyl-CoA hydrolase. Finally, most members of a clone library of bssA generated from the PFR had highest similarity to bssA from strain 15-1. Our study provides insights about the physiological capacities of a strain of Magnetospirillum isolated from a planted system where active rhizoremediation of toluene is taking place

Torasemide inhibits angiotensin II-induced vasoconstriction and intracellular calcium increase in the aorta of spontaneously hypertensive rats

Torasemide is a loop diuretic that is effective at low once-daily doses in the treatment of arterial hypertension. Because its antihypertensive mechanism of action may not be based entirely on the elimination of salt and water from the body, a vasodilator effect of this drug can be considered. In the present study, the ability of different concentrations of torasemide to modify angiotensin II (Ang II)-induced vascular responses was examined, with the use of an organ bath system, in endothelium-denuded aortic rings from spontaneously hypertensive rats. Ang II-induced increases of intracellular free calcium concentration ([Ca(2+)](i)) were also examined by image analysis in cultured vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats. A dose-response curve to Ang II was plotted for cumulative concentrations (from 10(-9) to 10(-6) mol/L) in endothelium-denuded aortic rings (pD(2)=7.5+/-0.3). Isometric contraction induced by a submaximal concentration of Ang II (10(-7) mol/L) was reduced in a dose-dependent way by torasemide (IC(50)=0.5+/-0.04 micromol/L). Incubation of VSMCs with different concentrations of Ang II (from 10(-10) to 10(-6) mol/L) resulted in a dose-dependent rise of [Ca(2+)](i) (pD(2)=7.5+/-0.3). The stimulatory effect of [Ca(2+)](i) induced by a submaximal concentration of Ang II (10(-7) mol/L) was blocked by torasemide (IC(50)=0.5+/-0.3 nmol/L). Our findings suggest that torasemide blocks the vasoconstrictor action of Ang II in vitro. This action can be related to the ability of torasemide to block the increase of [Ca(2+)](i) induced by Ang II in VSMCs. It is proposed that these actions might be involved in the antihypertensive effect of torasemide observed in vivo

Telomere Length Shows No Association with BRCA1 and BRCA2 Mutation Status

This study aimed to determine whether telomere length (TL) is a marker of cancer risk or genetic status amongst two cohorts of BRCA1 and BRCA2 mutation carriers and controls. The first group was a prospective set of 665 male BRCA1/2 mutation carriers and controls (mean age 53 years), all healthy at time of enrolment and blood donation, 21 of whom have developed prostate cancer whilst on study. The second group consisted of 283 female BRCA1/2 mutation carriers and controls (mean age 48 years), half of whom had been diagnosed with breast cancer prior to enrolment. TL was quantified by qPCR from DNA extracted from peripheral blood lymphocytes. Weighted and unweighted Cox regressions and linear regression analyses were used to assess whether TL was associated with BRCA1/2 mutation status or cancer risk. We found no evidence for association between developing cancer or being a BRCA1 or BRCA2 mutation carrier and telomere length. It is the first study investigating TL in a cohort of genetically predisposed males and although TL and BRCA status was previously studied in females our results don't support the previous finding of association between hereditary breast cancer and shorter TL

Cycling Phosphorus and Nitrogen through Cropping Systems in an Intensive Dairy Production Region

As pressure on the dairy industry to reduce its environmental impact increases, efficient recycling of manure nutrients through local cropping systems becomes crucial. The aim of this study was to calculate annual nitrogen (N) and phosphorus (P) budgets in six counties located in the Magic Valley, Idaho and estimate what distance manure would need to be transported to be in balance with crop nutrient demand given current dairy cattle populations and cropping systems. Our analysis suggests that crop N needs will not be met solely by manure, and synthetic fertilizer will need to be applied. However, to balance P with crop production, manure would need to be transported a minimum of 12.9 km from dairies and would have to replace synthetic fertilizer P on 91% of regional cropland. Education of producers and technical specialists would be necessary to improve the management of manure use in regional cropping systems. Technical solutions such as alternative diets for cattle and nutrient capture from manure streams will also likely be necessary to bring regional P into balance to protect environmental quality and improve the sustainability of the regional dairy industry

Structural evolution, optical gap and thermoelectric properties of CH3NH3SnBr3 hybrid perovskite, prepared by mechanochemistry

Direct bandgap semiconductors of the hybrid-perovskite family CH3NH3PbX3 (X = I, Br, Cl) exhibit outstanding light absorption properties and are the materials of choice for solar energy applications. As an alternative to poisonous Pb, tin-containing perovskites would show a lower effective mass thus exhibiting a higher charge carrier mobility. An auspicious candidate is CH3NH3SnBr3, with an estimated band gap of 1.902 eV, anticipating applications in photovoltaic devices for the visible to ultra-violet wavelength region. We describe that this perovskite can be prepared by ball milling in a straightforward way, yielding specimens with a superior crystallinity. A structural investigation from synchrotron X-ray powder diffraction (SXRD) data was essential to revisit the successive phase transitions this compound experiences down to 120 K, guided by specific heat capacity and DSC measurements. From the cubic structure identified at RT and 270 K, there is a gradual evolution of the patterns, analysed as a phase admixture between the cubic and the low-symmetry phase present at 160 K. This corresponds to an orthorhombic Pmc21 superstructure; this acentric space group enables polarization along the c-axis where there is a twofold screw axis, evidenced in the distribution of Sn-Br distances. Furthermore, there are two conspicuous changes in the orthorhombic framework, yet keeping the Pmc21 space group, which agree with the main calorimetric events (observed at 224 and 147 K). We interpret these changes as an interplay between the tilting of the SnBr6 octahedra of the inorganic framework and the breaking and reconstruction of H-bond interactions with the organic CH3NH+3 unit. The stereochemical effect of the lone electron pair of the Sn2+ ion is clear in the SnBr6 octahedral distortion. Diffuse reflectance UV/Vis spectroscopy yields an optical gap of ∼2.1 eV, in agreement with ab- initio calculations. A Seebeck coefficient of ∼2000 μV K-1 is determined near RT, which is one order of magnitude higher than those reported for other halide perovskites.Fil: Lopez, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentina. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Abia, Carmen. Institut Laue Langevin; Francia. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Gainza, Javier. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Kayser, Paula. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Nemes, Norbert. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Dura, Oscar J.. Universidad de Castilla-La Mancha; EspañaFil: Martinez, Jose L.. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Fernandez Diaz, Maria Teresa. Institut Laue Langevin; FranciaFil: Alvarez Galvan, M. Consuelo. Consejo Superior de Investigaciones Científicas; EspañaFil: Alonso, José Antonio. Instituto de Ciencia de Materiales de Madrid; Españ

Effect of gypsum on the early hydration of cubic and Na-doped orthorhombic tricalcium aluminate

The tricalcium aluminate (C3A) and sulfate content in cement influence the hydration chemistry, setting time and rheology of cement paste, mortar and concrete. Here, in situ experiments are performed to better understand the effect of gypsum on the early hydration of cubic (cub-)C3A and Na-doped orthorhombic (orth-)C3A. The isothermal calorimetry data show that the solid-phase assemblage produced by the hydration of C3A is greatly modified as a function of its crystal structure type and gypsum content, the latter of which induces non-linear changes in the heat release rate. These data are consistent with the in situ X-ray diffraction results, which show that a higher gypsum content accelerates the consumption of orth-C3A and the subsequent precipitation of ettringite, which is contrary to the cub-C3A system where gypsum retarded the hydration rate. These in situ results provide new insight into the relationship between the chemistry and early-age properties of cub- and orth-C3A hydration and corroborate the reported ex situ findings of these systems