178 research outputs found

    An activating mutation in the CRHR1 gene is rarely associated with pituitary-dependent hyperadrenocorticism in poodles

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    OBJECTIVES: Pituitary-dependent hyperadrenocorticism is the most common cause of naturally occurring hypercortisolism in dogs. CRHR1 expression in human and dog corticotrophinomas suggested that this gene affects pituitary tumorigenesis. The present study aimed to investigate mutations in the CRHR1 coding region in poodles with pituitary-dependent hyperadrenocorticism. METHODS: Fifty poodles with pituitary-dependent hyperadrenocorticism and 50 healthy poodles were studied. Genomic DNA was amplified by PCR and analyzed by Sanger sequencing. RESULTS: The novel CRHR1 p.V97M mutation was identified in one dog. This valine residue, located in the amino-terminal extracellular domain, exhibits high affinity for its corticotropin-releasing hormone (CRH) ligand. Bioinformatic analysis revealed structural rearrangements in the mutant protein, with a 17% increase in the surface binding affinity between CRHR1 and CRH. In vitro functional studies showed that mutant CRHR1 induced higher ACTH secretion than the wild type after stimulation with human CRH. CONCLUSION: These results suggest that germline activating mutations in CRHR1 may be a rare cause of pituitary hyperadrenocorticism in poodles

    iphasic oxidative denitrogenation with H2O2 of a simulated fuel using sustainable carbon nanotube catalysts

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    The presence of nitrogenated compounds in liquid fuels (e.g. quinoline (QN), azapyrene, pyrrole, indole or carbazole) is associated with a series of environmental and health issues [1], as upon their combustion, noxious NOx gases are formed. Typically, those heteroatoms are removed by hydrodenitrogenation (HDN), a process based on the application of H2 under high temperature and pressure [2]. However, due to the type of nitrogenated compounds found in crude oils, which consist mostly of cyclic structures containing two double bonds between N and C atoms, HDN fails to efficiently remove nitrogen without affecting the properties of the fuel [1]. Thus, alternatives to HDN have been sought, the removal of those nitrogenated compounds via oxidative processes being found as promising [1]. In oxidative denitrogenation (ODN), nitrogen-based compounds are oxidized towards more polar compounds, which can be further removed from the fuel with an extractant [3]. Furthermore, another contemporary issue is the production and accumulation of residues, especially plastic solid waste (PSW). PSW can be used as precursors for the synthesis of sustainable carbon nanotubes (CNTs), which could be further applied as catalysts in ODN. In this work, a nitrogen-rich fuel was simulated by dissolving QN (CQN-i-octane,0 = 1 g L-1) in 2,2,4-trimethylpentane (i-octane), and ODN was carried out using H2O2 as oxidant and CNTs (derived from a mixture of polymers simulating PSW) as catalysts, under a biphasic system (oxidation and extraction co-occurrence).This work was financially supported by project "PLASTIC_TO_FUEL&MAT – Upcycling Waste Plastics into Fuel and Carbon Nanomaterials" (PTDC/EQU-EQU/31439/2017), Base Funding - UIDB/50020/2020 of the Associate Laboratory LSRE-LCM - funded by national funds through FCT/MCTES (PIDDAC), and CIMO (UIDB/00690/2020) through FEDER under Program PT2020. Fernanda F. Roman acknowledges the national funding by FCT, Foundation for Science and Technology, and FSE, European Social Fund, through the individual research grant SFRH/BD/143224/2019.info:eu-repo/semantics/publishedVersio

    Oxidative denitrogenation of a simulated fuel under a biphasic green system

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    Este trabalho trata da desnitrificação catalítica de um combustível simulado (quinolina (QN) em 2,2,4-trimetilpentano) por oxidação com peróxido de hidrogénio em meio bifásico. Como catalisadores, foram utilizados três materiais: (i) ferro suportado em alumina (Fe/Al2O3) obtido por sol-gel, (ii) nanotubos de carbono (CNT) produzidos através da deposição química em fase de vapor de propileno (PP) sobre o catalisador anterior (Fe/Al2O3), e (iii) os CNT fornecidos pela Sigma Aldrich. A contribuição da adsorção e da extração foi avaliada, sendo ambas consideradas desprezáveis ou pouco efetivas para a remoção da QN. O desempenho de cada material foi analisado em testes de reação de 4 h, a 80 °C, através da monitorização da degradação de H2O2 e da concentração de QN em meio oleoso e aquoso. Como resultados, todos os materiais utilizados atenderam ao objetivo proposto, sendo 100% da QN removida da fase oleosa nos ensaios de oxidação bifásica. Em resumo, todos os catalisadores produzidos foram eficientes no processo proposto e são comparáveis ao desempenho obtido pelo CNT comercialThis work deals with the catalytic denitrogenation of a simulated fuel (quinoline (QN) in 2,2,4-trimethylpentane) by oxidation with hydrogen peroxide in a biphasic medium. As catalysts, three materials were used (i) iron supported on alumina (Fe/Al2O3) obtained by sol-gel, carbon nanotubes (CNT) produced by chemical vapor deposition of propylene (PP) growth on the previous catalyst (Fe/Al2O3) and (iii) a commercial sample of CNT supplied by Sigma Aldrich. The contribution of adsorption and extraction was also assessed, both being considered negligible or ineffective for the removal of QN. The performance of each catalyst was analysed in 4 h reaction tests, at 80 °C, by monitoring the degradation of H2O2 and the concentration of QN in the oily and aqueous media. As a result, all catalysts used met the proposed objective, with 100% of QN being removed from the oily phase in the biphasic oxidation tests. In summary, all the catalysts produced were efficient in the proposed process and are comparable to the performance obtained by the commercial CNT sample.This work was financially supported by project “PLASTIC_TO_FUEL&MAT – Upcycling Waste Plastics into Fuel and Carbon Nanomaterials” (PTDC/EQU-EQU/31439/2017), LA/P/0045/2020 (ALiCE), UIDB/50020/2020 and UIDP/50020/2020 (LSRE-LCM), funded by national funds through FCT/MCTES (PIDDAC) and CIMO (UIDB/00690/2020) through FEDER under Program PT2020. Fernanda F. Roman acknowledges the national funding by FCT, Foundation for Science and Technology, and FSE, European Social Fund, through the individual research grant SFRH/BD/143224/2019. Jose L. Diaz de Tuesta acknowledges the financial support through the program of “Atracción al Talento” of “Comunidad de Madrid” (Spain) for the individual research grant 2020-T2/AMB-19836.info:eu-repo/semantics/publishedVersio

    Pharmacogenetics of glucocorticoid replacement could optimize the treatment of congenital adrenal hyperplasia due to 21-hydroxylase deficiency

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    INTRODUCTION: 21-hydroxylase deficiency is an autosomal recessive disorder that causes glucocorticoid deficiency and increased androgen production. Treatment is based on glucocorticoid replacement; however, interindividual variability in the glucocorticoid dose required to achieve adequate hormonal control has been observed. OBJECTIVE: The present study aimed to evaluate the association between polymorphic variants involved inglucocorticoid action and/or metabolism and the mean daily glucocorticoid dose in 21-hydroxylase deficiency patients. METHODS: We evaluated 53 patients with classical forms of 21-hydroxylase deficiency who were receiving cortisone acetate. All patients were between four and six years of age and had normal androgen levels. RESULTS: The P450 oxidoreductase A503V, HSD11B1 rs12086634, and CYP3A7*1C variants were found in 19%, 11.3% and 3.8% of the patients, respectively. The mean ± SD glucocorticoid dose in patients with the CYP3A7*1C and wild-type alleles was 13.9 ± 0.8 and 19.5 ± 3.2 mg/m²/d, respectively. We did not identify an association between the P450 oxidoreductase or HSD11B1 allelic variants and the mean glucocorticoid dose. CONCLUSION: Patients carrying the CYP3A7*1C variant required a significantly lower mean glucocorticoid dose. Indeed, the CYP3A7*1C allele accounted for 20% of the variability in the cortisone acetate dose. The analysis of genes involved in glucocorticoid metabolism may be useful in the optimization of treatment of 21-hydroxylase deficiency

    Impact of Glucocorticoid Receptor Gene Polymorphisms on the Metabolic Profile of Adult Patients with the Classical Form of 21-Hydroxylase Deficiency

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    Background: CAH patients have an increased risk of cardiovascular disease, and it remains unknown if lifelong glucocorticoid (GC) treatment is a contributing factor. In the general population, glucocorticoid receptor gene (NR3C1) polymorphisms are associated with an adverse metabolic profile. Our aim was to analyze the association between the NR3C1 polymorphisms and the metabolic profile of CAH patients. Methodology: Sixty-eight adult patients (34SV/34SW) with a mean age of 28.4 +/- 9 years received dexamethasone (mean 0.27 +/- 0.11 mg/day) to obtain normal androgen levels. SW patients also received fludrocortisone (50 mu g/day). Metabolic syndrome (MetS) was defined by the NCEP ATPIII criteria and obesity by BMI >= 30 kg/m(2). NR3C1 alleles were genotyped, and association analyses with phenotype were carried out with Chi-square, t-test and regression analysis. Results: Obesity and MetS were observed in 23.5% and 7.3% of patients, respectively, and were not correlated with GC doses and treatment duration. BMI was positively correlated with blood pressure (BP), triglycerides (TG), LDL-c levels and HOMA-IR and inversely correlated with HDL-c levels. BclI and A3669G variants were found in 26.4% and 9.6% of alleles, respectively. Heterozygotes for the BclI polymorphism presented with higher BMI (29 kg/m(2) +/- 5.3 vs. 26 kg/m(2) +/- 5.3, respectively) and waist circumference (89 cm +/- 12.7 vs. 81 cm +/- 13, respectively) compared to wild-type subjects. Hypertension was found in 12% of patients and heterozygotes for the BclI polymorphism presented higher systolic BP than wild type subjects. Low HDL-c and high TG levels were identified in 30% and 10% of patients, respectively, and were not associated with the NR3C1 polymorphisms. A3669G carriers and non-carriers did not differ. Conclusion: In addition to GC therapy, the BclI GR variant might play an important role in obesity susceptibility in CAH patients. Genotyping of GR polymorphisms could result in the identification of a subgroup at risk patients, allowing for the establishment of personalized treatment and the avoidance of long-term adverse consequences.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo - FAPESP [09/54394-4, 09/54238-2]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico - CNPq [305117/2009-2, 301339/2008-9]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

    ESTUDO DA QUALIDADE DAS ÁGUAS DO RIO MAROMBAS (SC/BRASIL), UTILIZANDO PARÂMETROS FÍSICO-QUÍMICOS E BIOENSAIOS.

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    O presente trabalho propôs realizar estudos preliminares de avaliação da qualidade das águas do Rio Marombas (SC-Brasil), utilizando parâmetros físico-químicos e bioensaios. Amostras de águas do Rio Marombas foram coletadas em 3 pontos e realizada a determinação de pH, oxigênio dissolvido (OD), análise de agroquímicos, hidrocarbonetos policíclicos aromáticos (HPA’s), compostos orgânicos voláteis (COV’s) e bifenilas policloradas (PCB’s). Foram executados ensaios de toxicidade aguda (CL50) em microcrustáceos Artemia sp. e de fitotoxicidade em Allium cepa L. avaliada pela inibição de crescimento e peso de raízes e pelos biomarcadores de estresse oxidativo glutationa reduzida (GSH) e peroxidação lipídica. Os resultados dos parâmetros físico-químicos indicaram que os valores de pHestiveram compatíveis com padrões previstos pela legislação. Foi constatada a presença dos agroquímicos metomil nos Pontos 1 e 2 e metconazol no Ponto 1. Os bioensaios revelaram que não houve toxicidade em Artemia sp. e ausência de inibição de crescimento e peso de raízes em Allium cepa L. A concentração de GSH estava significativamente aumentada no Ponto 3 quando comparada ao Ponto 1 e ao controle negativo. Não foi observada diferença significativa na avaliação de peroxidação lipídica entre os diferentes grupos. Esses resultados indicam que as águas do Rio Marombas podem estar sendo contaminadas por agroquímicos, sugerindo a necessidade de implementação de sistema de monitoramento periódico de sua qualidade.Palavras-chave: rio Marombas; parâmetros físico-químicos; bioensaiosSTUDY OF WATER QUALITY FROM THE MAROMBAS RIVER (SC/BRAZIL) USING THE PHYSICOCHEMICAL PARAMETERS AND BIOASSAYS.ABSTRACTThe present study proposed preliminary studies assessing the quality of water from the river Marombas (SCBrazil) using the physicochemical parameters and bioassays. Samples of water from Marombas river were collected at three points and it was determined the pH, dissolved oxygen (DO), concentration of agrochemicals, polycyclic aromatic hydrocarbons (PAH’s), volatile organic compounds (VOC`s) and polychlorinated biphenyls (PCB´s). Acute toxicity tests (LC50) were carried out in microcrustaceans Artemia sp. and phytotoxicity tests in Allium cepa L. assessed through theinhibition of growth and weight of roots and by biomarkers of oxidative stress reduced glutathione (GSH) and lipid peroxidation. The results of physicochemical parameters indicated that the pH values were consistent with standards established by the legislation. It could be observed the presence of the agrochemicals methomyl in Points 1 and 2 and metconazole in Point 1. The bioassays showed absence of the acute toxicity in Artemia sp. and there was no inhibition of growth and weight of roots in Allium cepa L. The concentration of GSH was significantly increased (P<0.05) in Point 3 when compared to Point 1 and the negative control. No significant difference could be observed in the evaluation of lipid peroxidation between different groups. These results demonstrate that the water of the Marombas river is contaminated by agrochemicals, suggesting the necessity of implementing a system of monitoring its quality.Key words: Marombas river, physicochemical parameters, bioassay
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