1,738 research outputs found

    Future perspectives of PoseidOn stratification for clinical practice and research

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    A total of 50% of patients undergoing IVF treatment has previously been estimated to fulfill the POSEIDON classification criteria; importantly, although the reproductive prognosis differs between patients, POSEIDON patients share the same characteristic of a low ovarian response to exogenous gonadotropin stimulation\u2014independent of age. POSEIDON patients require focused attention as regards ovarian stimulation in order to increase the chances of having at least one euploid blastocyst for transfer\u2014the success criterion for stimulation set forth by the POSEIDON Group. The key to success seems to be individualization in all steps of treatment. In this perspective article we discuss the future impact of the POSEIDON stratification for daily clinical practice as well as for research

    Determinação quantitativa de corantes sulfurosos por potenciometria

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    Os corantes sulfurosos têm, desde o início da sua aplicação há mais de um século1, uma grande aplicação na Indústria Têxtil. De facto, embora quase todas as cores possam ser obtidas com corantes de outros tipos, a utilização de corantes sulfurosos para a obtenção de tons escuros (como o preto e o azul marinho) em fibras celulósicas continua a ser muito elevada2 . No entanto, devido à baixa solubilidade em água deste tipo de corantes, a sua quantificação é difícil. Associado a este problema encontram-se, ainda, várias dificuldades inerentes às técnicas analíticas. Nesta comunicação, é apresentada uma técnica de doseamento por titulação potenciométrica, baseada no método para doseamento de sulfuretos solúveis5. O procedimento consiste numa titulação potenciométrica por retorno, com sulfureto de sódio, após oxidação completa do corante com hexacianoferrato (III) de potássi

    Carbon Materials Derived from Cyano-Based IL@ZIF-8 Composites for CO2 Sorption Separation Systems

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    Additionally, this work was partially supported by the Asso- ciate Laboratory for Green Chemistry, LAQV, which is funded by national funds from FCT/MCTES (LA/P/00 08/2020) .The sorption capacity and selectivity of pre- and post-carbonized cyano-based metal-organic framework (MOF) composite materials (cyano-based IL@ZIF-8) were investigated for the first time. The influence of the ionic liquid (IL) loading and number of cyano groups in the IL anion on a materials gas sorption separation performance was studied. Sorption-desorption equilibrium isotherms of CO2, CH4, and N2 were measured at 303 K in the ZIF-8, cyano-based IL@ZIF-8 composites and their derived carbon materials. The IL loading did not significantly affect the gas uptake of the carbon materials, while for the composites its main contribution was on the increase of the selectivity. The number of cyano groups in the anion played a key role in the sorption capacity and selectivity performance as it directly affects the N content and textural properties. The carbon material obtained from ZIF-8 (C_ZIF-8) precursor showed the best sorption capacity for all gases, just being surpassed by the C_15%[C6MIM][B(CN)4]@ZIF-8 carbon up to 1 bar. In terms of selectivity performance, carbons based on [C6MIM][B(CN)4]@ZIF-8 composites revealed to be equally or more selective than C_ZIF-8, increasing up to 65% between 0 and 1 bar depending on the mixture. The composites produced and their respective carbons demonstrated a promising application as sorbents for post-combustion CO2 separation systems.publishersversionpublishe

    Robinow Syndrome and otorhinolaryngoly - A case report

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    A Síndrome de Robinow é uma doença genética rara, com menos de 200 casos registados no mundo. Caracteriza-se pelo encurtamento mesomélico dos membros, baixa estatura, hipoplasia genital externa e uma fácies fetal. A sua transmissão pode ser autossómica recessiva ou dominante. Este artigo descreve o caso clínico de uma criança com diagnóstico pós-natal de Síndrome de Robinow esporádica autossómica dominante. Aos 12 anos de idade as anomalias otorrinolaringológicas incluíam a presença de uma bossa frontal, nariz curto com dorso largo, hipoplasia da maxila, fenda palatina corrigida e hipoacusia de condução bilateral. A Síndrome de Robinow é uma condição geneticamente heterogénea que pode ser facilmente diagnosticada na infância ou mesmo na avaliação pré-natal. O acompanhamento e intervenção otorrinolaringológicos podem melhorar o desenvolvimento e a qualidade de vida destas crianças.info:eu-repo/semantics/publishedVersio

    Détermination quantitative des colorants au soufre - dosage potentiométrique

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    Dans l’Industrie Textile, l’optimisation des procédés d’ennoblissement et la récupération et/ou réutilisation des produits chimiques sont des aspects importants à envisager. Plus précisément, il en est ainsi dans le cas des colorants et des produits auxiliaires utilisés en teinture.En particulier, les colorants au soufre et l’indigo posent de réels problèmes. De faible solubilité dans l'eau sous forme oxydée, leur l'application éxige l'utilisation d’un réducteur pour leur mise en solution dans le bain de teinture. Afin de surmonter ces difficultés, on propose ici une nouvelle méthode de dosage de colorants au soufre

    Avaliação dos Resultados do Cross-Linking de Colagénio Corneano em Doentes com Queratocone: a Nossa Experiência

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    Objectivo: Avaliar os resultados visuais e queratométricos do tratamento com cross-linking de colagénio corneano (CXL) no queratocone progressivo realizado no Centro Hospitalar de Entre Douro e Vouga durante o período de 1 ano. Material e Métodos: Estudo retrospetivo no qual foram incluídos 15 olhos (15 doentes) com queratocone progressivo. Todos os pacientes foram submetidos ao tratamento com CXL com riboflavina e luz ultravioleta-A segundo o protocolo de Dresden. 8 olhos completaram 12 meses de seguimento e, 7 olhos completaram 6 meses. Avaliámos a acuidade visual com e sem correcção, cilindro refractivo e equivalente esférico, topografia corneana e paquimetria com Pentacam®, assim como os parâmetros obtidos com o Ocular Response Analyzer®. Resultados: Verificou-se uma melhoria da melhor acuidade visual corrigida média de 0.56 +/- 0.18 para 0.60 +/- 0.18 aos 3 meses, atingindo aos 6 meses 0.69, diferença estatisticamente significativa (p=0.007) e aos 12 meses 0.72 (p=0.003). Os valores do cilindro refractivo e equivalente esférico diminuíram após o procedimento mas sem significado estatístico. Em todos os olhos tratados verificou-se estabilização da progressão. A média da queratometria máxima diminui significativamente de 51.11D pré-operatório para 49.63D (p=0.002) aos 6 meses e para 50.0 D aos 12 meses (p=0.01). Conclusões: O CXL de colagénio é um tratamento promissor para o queratocone evolutivo pois permite atrasar a progressão da doença e, em alguns casos, melhorar os parâmetros visuais, refractivos e topográficos. Os nossos resultados mostram uma melhoria funcional e morfológica, com a estabilização da progressão da doença, sendo necessário, no entanto, resultados a longo prazo.info:eu-repo/semantics/publishedVersio

    Reductive intramolecular cyclization of D-glucose-based unsaturated substrates by indirect electrochemical approach in “Green” media

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    Radical cyclisation continues to be a central methodology for the preparation of natural products containing heterocyclic rings. Hence, some electrochemical results obtained by cyclic voltammetry and controlled-potential electrolysis in the study of electroreductive intramolecular cyclisation of ethyl (2S, 3R)-2- bromo-3-propargyloxy-3-(2’,3’,4’,6’-tetra-O-acetyl-β-D-glucopyranosiloxy) propanoate (1) promoted by (1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetra-decane)nickel(I), [Ni(tmc)]+, electrogenerated at glassy carbon cathodes in ethanol and ethanol/water mixtures containing tetraalkylammonium salts, are presented. During controlled-potential electrolyses of solutions containing [Ni(tmc)]2+ and acetylated D-glucose-based bromo propargyl ester (1) catalytic reduction of the latter proceeds via one-electron cleavage of the carbon–bromine bond to form a radical intermediate that undergoes cyclization to afford the substituted tetrahydrofurans.Fundação para a Ciência e a Tecnologia (FCT

    Effect of environmental factors on seminal microbiome and impact on sperm quality

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    ObjectiveThis review provides a comprehensive overview of the existing research on the seminal microbiome and its association with male infertility, while also highlighting areas that warrant further investigation.MethodsA narrative review was conducted, encompassing all relevant studies published between 1980-2023 on the male reproductive tract microbiome in humans. This review considered studies utilizing culture-based, polymerase chain reaction (PCR)-based, and next-generation sequencing (NGS)-based methodologies to analyze the microbiome. Data extraction encompassed sample types (semen or testicular tissue), study designs, participant characteristics, employed techniques, and critical findings.ResultsWe included 37 studies comprising 9,310 participants. Among these, 16 studies used culture-based methods, 16 utilized NGS, and five employed a combination of methods for microorganism identification. Notably, none of the studies assessed fungi or viruses. All NGS-based studies identified the presence of bacteria in all semen samples. Two notable characteristics of the seminal microbiome were observed: substantial variability in species composition among individuals and the formation of microbial communities with a dominant species. Studies examining the testicular microbiome revealed that the testicular compartment is not sterile. Interestingly, sexually active couples shared 56% of predominant genera, and among couples with positive cultures in both partners, 61% of them shared at least one genital pathogen. In couples with infertility of known causes, there was an overlap in bacterial composition between the seminal and vaginal microbiomes, featuring an increased prevalence of Staphylococcus and Streptococcus genera. Furthermore, the seminal microbiome had discernible effects on reproductive outcomes. However, bacteria in IVF culture media did not seem to impact pregnancy rates.ConclusionExisting literature underscores that various genera of bacteria colonize the male reproductive tract. These organisms do not exist independently; instead, they play a pivotal role in regulating functions and maintaining hemostasis. Future research should prioritize longitudinal and prospective studies and investigations into the influence of infertility causes and commonly prescribed medication to enhance our understanding of the seminal microbiota’s role in reproductive health
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