2,454 research outputs found

    Interactions between potassium channels and serotonin in pulmonary arterial hypertension

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    Pulmonary arterial hypertension (PAH) is a progressive disease which results from increases in mean pulmonary artery pressure and pulmonary vascular resistance. If untreated it leads to right ventricular failure and death. 5-Hydroxytryptamine (5-HT) has been implicated in the disease process and is thought to promote both vasoconstriction and remodelling of the pulmonary vasculature. The activity of potassium ion (K+) channels plays a major role in influencing pulmonary artery tone by regulating resting membrane potential, intracellular Ca2+ concentration and contraction of vascular smooth muscle. This study aimed to investigate possible interactions between 5-HT and K+ channels in the development of PAH in the mouse. The actions of 5-HT and a range of K+ channel blockers were investigated on isolated intralobar pulmonary arteries (IPA) from wild type (WT) mice and mice over-expressing the serotonin transporter (5HTT), which spontaneously develop PAH. Both 5-HT and linopirdine, a KCNQ K+ channel inhibitor, were found to induce contraction of IPA, but were more potent in IPA from WT mice than 5-HTT+ mice. The 5-HT induced vasoconstriction was found to involve influx of Ca2+ from the extracellular space, Ca2+ release from the sacroplasmic reticulum and a rho kinase–dependent increase in the sensitivity of the contractile machinery of pulmonary artery smooth muscle cells (PASMC) to intracellular Ca2+. Ca2+ entered the cell via both voltage operated calcium channels (VOCC), activated by membrane depolarisation, and a separate Ca2+ entry pathway, the latter appearing to contribute more in 5-HTT+ mice. The effects of linopirdine were shown to be due entirely to the entry of Ca2+ through VOCC in both WT and 5-HTT+ mice IPA. The difference in vasoconstrictor potency between WT and 5HTT+ mice was not seen with any other K+ channel blocker, suggesting a selective loss of KCNQ channels and/or VOCC in PAH resulting from 5HTT over expression. KCNQ channel activity was further investigated using the KCNQ channel openers, flupirtine and retigabine. These agents were more potent in dilating IPA from WT mice compared to 5-HTT+ mice, consistent with the loss of expression or activity of KCNQ channels in 5-HTT+ mice. Despite this, orally administered flupirtine was shown to reverse two indices of established PAH in the 5HTT+ mice; right ventricular pressure and right ventricular hypertrophy. This action of flupirtine was also seen in chronic hypoxic mice, where it prevented the development of PAH. In conclusion, this study provides evidence of an interaction between KCNQ channels and the 5-HT system in the development of PAH. By showing that a KCNQ channel opener can attenuate PAH, both in the developing and established disease situation, this study proposes a new potential therapeutic target in the treatment of PAH

    Jarosite versus Soluble Iron-Sulfate Formation and Their Role in Acid Mine Drainage Formation at the Pan de Azúcar Mine Tailings (Zn-Pb-Ag), NW Argentina

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    Secondary jarosite and water-soluble iron-sulfate minerals control the composition of acid mine waters formed by the oxidation of sulfide in tailings impoundments at the (Zn-Pb-Ag) Pan de Azúcar mine located in the Pozuelos Lagoon Basin (semi-arid climate) in Northwest (NW) Argentina. In the primary zone of the tailings (9.5 wt % pyrite-marcasite) precipitation of anglesite (PbSO4), wupatkite ((Co,Mg,Ni)Al2(SO4)4) and gypsum retain Pb, Co and Ca, while mainly Fe2+, Zn2+, Al3+, Mg2+, As3+/5+ and Cd2+ migrate downwards, forming a sulfate and metal-rich plume. In the oxidation zone, jarosite (MFe3(TO4)2(OH)6) is the main secondary Fe3+ phase; its most suitable composition is M = K+, Na+, and Pb2+and TO4 = SO42−; AsO42−. During the dry season, iron-sulfate salts precipitate by capillary transport on the tailings and at the foot of DC2 (tailings impoundment DC2) tailings dam where an acid, Fe2+ rich plume outcrops. The most abundant compounds in the acid mine drainage (AMD) are SO42−, Fe2+, Fe3+, Zn2+, Al3+, Mg2+, Cu2+, As3+/5+, Cd2+. These show peak concentrations at the beginning of the wet season, when the soluble salts and jarosite dissolve. The formation of soluble sulfate salts during the dry season and dilution during the wet season conform an annual cycle of rapid metals and acidity transference from the tailings to the downstream environment.Fil: Murray, Jesica María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Kirschbaum, Alicia Matilde. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Dold, Bernhard. Sustainable Mining Research & Consult EIRL; ChileFil: Mendes Guimaraes, Edi. Universidade do Brasilia; BrasilFil: Pannunzio Miner, Elisa Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentin

    Seasonal variation of Helicogermslita (Xylariaceae) ascospores in the atmosphere of Bahía Blanca city, Argentina

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    Ascosporas asignables a Helicogermslita (Xylariaceae, Ascomycota) fueron registradas en muestras de aire de la ciudad de Bahía Blanca. Las xilariáceastienen diversos roles ecológicos (como fitopatógenos, endófitos, descomponedores de madera, productores de múltiples metabolitos secundarios, etc.). El objetivo del trabajo fue determinar a qué especie de Helicogermslita correspondía el tipo esporal hallado, y analizar su dinámica de dispersión en la atmósfera de la ciudad de Bahía Blanca. Las muestras se tomaron diariamente con un equipo volumétrico tipo Hirst ubicado en una zona residencial a 12 m de altura. Durante el año 2016, se registraron las concentraciones diarias de 27 diferentes tipos esporales, entre ellos, el tipo Helicogermslita. El índice anual de esporas para el tipo Helicogermslita fue de 145 esporas/m3 de aire, cifra que representó un 0.02% en relación al total de esporas fúngicas halladas. La mayor representación ocurrió durante el verano y otoño, mientras que el invierno resultó la estación en donde estuvo menos representada. Al analizar la relación entre la aparición de esporas y algunos factores meteorológicos, la humedad relativa constituyó el factor más importante, registrándose correlación positiva y significativa entre él y la concentración de esporas. Las esporas halladas en el aire de Bahía Blanca fueron identificadas como H. cf. celastri. No pudo establecerse el sitio de origen de las esporas.The genus Helicogermslitawas registered in several European countries, India, New Zeeland, South Africa and Chile. While the natural habitat of the species are plant substrates, in Argentina ascospores from Helicogermslita were observed in air samples from Bahía Blanca city. Members of Xylariaceae are recognized as plant pathogens, endophytes or wood decomposers. The aim of this work was to identify the spore type named after Helicogermslitaand to analyze its dynamics of dispersion in Bahía Blanca atmosphere. Samples were taken weekly with a Lanzoni sampler (Hirst methodology) located in a residential area 15 meters high. Daily and schedules data of the concentration from Helicogermslitaspores were analyzed during 2016. The annual index of Helicogermslitaspore type was of 145 spores/m3, that represented 0.02% in relation to the total fungal spores found. The highest values were observed in summer and fall, while winter turned out to be the least represented season. The statistical analyses showed a relationship between the appearance of spores and some meteorological parameters, the relative humidity was the most important factor responsible of the increase in concentration of spores with a significant positive correlation. These ascospores were identified as H. cf. celastri. The site of origin of the spores could not be established.Key words:air; fungal spores; Ascomycota; Hirst sampler; aerobiology.Fil: Castillo, Luciana Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; ArgentinaFil: Bianchinotti, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Murray, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; Argentin

    Henry J. Kaiser Family Foundation; National Alliance of State and Territorial AIDS Directors - National ADAP Monitoring Project Annual Report

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    Based on a survey of AIDS Drug Assistance Programs (ADAPs), which provide prescription drugs to low-income, uninsured, and underinsured HIV/AIDS patients, provides an overview of ADAPs' operations, developments, challenges, and policy and program changes

    Composition, Repellent, and Insecticidal Activities of Two South American Plants against the Stored Grain Pests Tribolium castaneum and Tribolium confusum (Coleoptera: Tenebrionidae)

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    As part of a screening program to evaluate the biological activity of indigenous plants, we report the composition and the bioactivity of essential oils (EOs) extracted from Te de Burro ´ Aloysia polystachya [(Griseb.) Moldenke] and Lemon VerbenaAloysia citriodora [Palau] against two of the most widespread secondary pests of stored products, the red flour beetle Tribolium castaneum [Herbst] and the confused flour beetle Tribolium confusum [Jacqueline du Val]. Analysis by gas chromatography-mass spectrometry of the EOs led the identification of their major constituents and their relative proportions. EO ofA. citriodorashowed the highest repellent activity against both beetles (>70%). On the other hand, both plants showed fumigant toxicity only against T. confusum, without significant differences between them (LC50 values of 5.92 and 5.53 mg/L air forA. polystachya andA. citriodora, resp.). For contact toxicity (topical applications) the EO ofA. polystachyawas more effective (LD50 = 7.35ug/insect) than the EO ofA. citriodora (LD50 = 13.8g/insect) only against T. castaneum. On the other hand, T. confusum was not susceptible by contact to any of these EOs. These results provide important tools for the development of an Integrated Pest Management (IPM) program.Fil: Benzi, Verónica Soledad. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados II; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Stefanazzi, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados II; ArgentinaFil: Murray, Ana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Werdin Gonzalez, Jorge Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Ferrero, Adriana Alicia. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados II; Argentin

    Geological-geomorphological and geochemical control on low arsenic concentration in the Lerma valley groundwater between the two high arsenic geologic provinces of Chaco-Pampean plain and Puna

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    Argentina is known for having one of the most extensive areas with high arsenic (As) concentration in groundwater in the world. These areas correspond to two main geological provinces, the Puna plateau and the Chaco-Pampean plain. In this large territory, there are some specific environments where the As concentration in groundwater is lower, and in some cases within the recommended limits for drinking water. In our study, we analyze and interpret the low arsenic concentrations reported for the Lerma valley, the easternmost intermontane basin of the Cordillera Oriental, located between the aforementioned high-arsenic geological provinces. The groundwater from this valley is used for the consumption of more than 600.000 inhabitants in the city of Salta and nearby towns. The incipient development of the valley since the late Miocene and the subsequent tectonic and climatic evolution favored low As concentrations with respect to the Puna and the Chaco-Pampean plain. The high-energy sedimentary environments thatcharacterized the area during Plio-Quaternary times and the composition of the sediments have controlled the characteristics of sediments the multilayered aquifer. Moreover, the absence of geogenic arsenic sources, climate, high rain infiltration rate, near neutralpH,redox conditions, and wells construction with screens settledincoarse productive layers favor groundwater of good quality.The geological and tectonic evolution of the Lerma valley could be extrapolated to other similar valleys in the NW of Argentinaand can be useful as tool for exploration of good quality groundwater. This is of high importance in Latin American territories with high As concentration in groundwater such as Argentina.Fil: Murray, Jesica María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina. University of Strasbourg; FranciaFil: Romero Orué, María Angélica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: López, Emilce de Las Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: García, Víctor. Geomap S.a.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universitat Potsdam; AlemaniaFil: Kirschbaum, Alicia Matilde. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentin

    Henry J. Kaiser Family Foundation - National ADAP Monitoring Project Annual Report 2007

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    Provides the latest data on state AIDS Drug Assistance Programs (ADAPs), which provide HIV/AIDS-related prescription drugs to low-income, uninsured, and underinsured individuals living with HIV/AIDS

    The Protective Effect of Neighbourhood Collective Efficacy On Family Violence and Youth Antisocial Behaviour in Two South Korean Prospective Longitudinal Cohorts

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    Neighbourhood collective efficacy has been proposed as a protective factor against family violence and youth antisocial behaviour. However, little is known about its impact on parent and child behaviour in non-Western countries. Using data from two population-based prospective cohorts from South Korea, including primary school students aged 10–12 years (N = 2844) and secondary school students aged 15–17 years (N = 3449), we examined the interplay between collective efficacy, family violence, and youth antisocial behaviour, and whether effects vary by SES. In a first series of models, in both samples, higher levels of collective efficacy were associated with lower levels of family violence, whereas higher levels of family violence were associated with higher levels of youth antisocial behaviour. There was no direct effect of collective efficacy on youth antisocial behaviour; however, there was an indirect effect via family violence. Although these effects were more pronounced in low SES children, there was no evidence of moderation by SES. In a second series of models, in primary school students, collective efficacy was not associated with youth antisocial behaviour. However, there was a direct effect of collective efficacy on family violence, even after adjusting for youth antisocial behaviour. Again, there was no evidence of moderation by SES. In secondary school students, the pattern of results was less consistent, however, again, suggesting more pronounced effects of collective efficacy in low SES children. The findings suggest that collective efficacy may influence family violence more directly, whereas youth antisocial behaviour may be affected more indirectly through the family environment. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10802-021-00869-y

    Are fetal growth impairment and preterm birth causally related to child attention problems and ADHD?:Evidence from a comparison between high-income and middle-income cohorts

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    Cross-cohort comparison is an established method for improving causal inference. This study compared 2 cohorts, 1 from a high-income country and another from a middle-income country, to (1) establish whether birth exposures may play a causal role in the development of childhood attention problems; and (2) identify whether confounding structures play a different role in parent-reported attention difficulties compared with attention deficit hyperactivity disorder (ADHD) diagnoses.Birth exposures included low birth weight (LBW), small-for-gestational age (SGA), small head circumference (HC) and preterm birth (PTB)). Outcomes of interest were attention difficulties (Strengths and Difficulties Questionnaire, SDQ) and ADHD (Development and Well-Being Assessment, DAWBA). Associations between exposures and outcomes were compared between 7-year-old children from the Avon Longitudinal Study of Parents and Children (ALSPAC) in the UK (N=6849) and the 2004 Pelotas cohort in Brazil (N=3509).For attention difficulties (SDQ), the pattern of association with birth exposures was similar between cohorts: following adjustment, attention difficulties were associated with SGA (OR=1.59, 95% CI 1.20 to 2.19) and small HC (OR=1.64, 95% CI 1.11 to 2.41) in ALSPAC and SGA (OR=1.35, 95% CI 1.04 to 1.75) in Pelotas. For ADHD, however, the pattern of association following adjustment differed markedly between cohorts. In ALSPAC, ADHD was associated with LBW (OR=2.29, 95% CI 1.09 to 4.80) and PTB (OR=2.33, 95% CI 1.23 to 4.42). In the Pelotas cohort, however, ADHD was associated with SGA (OR=1.69, 95% CI 1.02 to 2.82).The findings suggest that fetal growth impairment may play a causal role in the development of attention difficulties in childhood, as similar associations were identified across both cohorts. Confounding structures, however, appear to play a greater role in determining whether a child meets the full diagnostic criteria for ADHD
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