161 research outputs found

    Ion-Transfer Voltammetric Behavior of Propranolol at Nanoscale Liquid-Liquid Interface Arrays

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    In this work, the ion-transfer voltammetric detection of the protonated β-blocker propranolol was explored at arrays of nanoscale interfaces between two immiscible electrolyte solutions (ITIES). Silicon nitride nanoporous membranes with 400 pores in a hexagonal arrangement, with either 50 or 17 nm radius pores, were used to form regular arrays of nanoITIES. It was found that the aqueous-to-organic ion-transfer current continuously increased steadily rather than reaching a limiting current plateau after the ion-transfer wave; the slope of this limiting current region was concentration dependent and associated with the high ion flux at the nanointerfaces. Electrochemical data were examined in terms of an independent nanointerface approach and an equivalent microdisc approach, supported by finite element simulation. In comparison to the larger interface configuration (50 nm radius), the array of 17 nm radius nanoITIES exhibited a 6.5-times higher current density for propranolol detection due to the enhanced ion flux arising from the convergent diffusion to smaller electrochemical interfaces. Both nanoITIES arrays achieved the equivalent limits of detection, 0.8 μM, using cyclic voltammetry. Additionally, the effect of scan rate on the charging and faradaic currents at these nanoITIES arrays, as well as their stability over time, was investigated. The results demonstrate that arrays of nanoscale liquid–liquid interfaces can be applied to study electrochemical drug transfer, and provide the basis for the development of miniaturized and integrated detection platforms for drug analysis

    Genetic diversity analysis in the section Caulorrhizae (genus Arachis) using microsatellite markers

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    Diversity in 26 microsatellite loci from section Caulorrhizae germplasm was evaluated by using 33 accessions of A. pintoi Krapov. & W.C. Gregory and ten accessions of Arachis repens Handro. Twenty loci proved to be polymorphic and a total of 196 alleles were detected with an average of 9.8 alleles per locus. The variability found in those loci was greater than the variability found using morphological characters, seed storage proteins and RAPD markers previously used in this germplasm. The high potential of these markers to detect species-specific alleles and discriminate among accessions was demonstrated. The set of microsatellite primer pairs developed by our group for A. pintoi are useful molecular tools for evaluating Section Caulorrhizae germplasm, as well as that of species belonging to other Arachis sections

    Predictors of complications in gynaecological oncological surgery: a prospective multicentre study (UKGOSOC-UK gynaecological oncology surgical outcomes and complications)

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    Background: There are limited data on surgical outcomes in gynaecological oncology. We report on predictors of complications in a multicentre prospective study. / Methods: Data on surgical procedures and resulting complications were contemporaneously recorded on consented patients in 10 participating UK gynaecological cancer centres. Patients were sent follow-up letters to capture any further complications. Post-operative (Post-op) complications were graded (I–V) in increasing severity using the Clavien-Dindo system. Grade I complications were excluded from the analysis. Univariable and multivariable regression was used to identify predictors of complications using all surgery for intra-operative (Intra-op) and only those with both hospital and patient-reported data for Post-op complications. / Results: Prospective data were available on 2948 major operations undertaken between April 2010 and February 2012. Median age was 62 years, with 35% obese and 20.4% ASA grade ⩾3. Consultant gynaecological oncologists performed 74.3% of operations. Intra-op complications were reported in 139 of 2948 and Grade II–V Post-op complications in 379 of 1462 surgeries. The predictors of risk were different for Intra-op and Post-op complications. For Intra-op complications, previous abdominal surgery, metabolic/endocrine disorders (excluding diabetes), surgical complexity and final diagnosis were significant in univariable and multivariable regression (P<0.05), with diabetes only in multivariable regression (P=0.006). For Post-op complications, age, comorbidity status, diabetes, surgical approach, duration of surgery, and final diagnosis were significant in both univariable and multivariable regression (P<0.05). / Conclusions: This multicentre prospective audit benchmarks the considerable morbidity associated with gynaecological oncology surgery. There are significant patient and surgical factors that influence this risk

    Validation of the questionnaire on beliefs about medication with type 2 diabetic patients

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    O presente trabalho teve como objectivo validar o Questionário Crenças sobre a Medicação, que avalia Crenças Gerais e Crenças Específicas, estudando suas propriedades psicométricas em uma amostra de 387 pacientes diabéticos tipo 2. O estudo de validade para as Crenças Gerais revelou uma solução de um factor, com um alfa de 0,76, e para as Crenças Específicas, dois factores – Necessidades e Preocupações –, com um alfa de 0,77 e 0,69 respectivamente. Quanto à validade de constructo, verificou-se uma relação entre as Crenças Gerais e a subescala Necessidades das Crenças Específicas com Adesão à Medicação, avaliada pela Escala de Avaliação de Aderência Médica. O instrumento apresenta boas qualidades psicométricas para ser utilizado em pacientes diabéticos tipo 2.The present paper focused on the validation of the Questionnaire on Beliefs about Medication, which assesses both General Beliefs and Specific Beliefs. The psychometric properties of the instrument were analyzed on a sample of 387 type 2 diabetic patients. The validity study for General Beliefs found a unifactorial solution, with an alpha of .76, and for Specific Beliefs, a two-factor solution – Necessities and Concern –, with an alpha of .77 and .69, respectively. In terms of construct validity, a relationship between General Beliefs, subscale Necessities from Specific Beliefs, and adherence to medication, as evaluated by Medical Adherence Rating Scale, was found. The instrument presents good psychometric qualities to be used in type 2 diabetic patients.Fundação para a Ciência e Tecnologia (FCT

    Identifying water stress-response mechanisms in citrus by in silico transcriptome analysis

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