10,117 research outputs found
Aromatase Inhibitors in Male Adolescents with Idiopathic Short Stature
Introdução: O efeito dos fármacos inibidores da aromatase (IA) na estatura de jovens do sexo masculino com baixa estatura idiopática (BEI) tem vindo a ser estudado desde que foi evidenciado o papel dos estrogénios na paragem do crescimento linear. Os ensaios clínicos aleatorizados, duplamente cegos, de caso-controlo com letrozol indicam impacto positivo na previsão de estatura final em jovens do sexo masculino com BEI, com ou sem atraso constitucional do crescimento e puberdade. Por persistirem aspetos de segurança a requerer melhor estudo, a sua utilização terapêutica continua a ser off label. Objetivos: Tendo em vista a implementação de um ensaio clínico sobre a terapêutica com IA em jovens do sexo masculino com BEI procedeu-se a uma revisão sistemática da literatura, na qual se fundamenta a proposta de protocolo apresentada. Métodos: Pesquisa na base de dados eletrónica Medline de revisões sistemáticas, ensaios clínicos alea-torizados controlados e referências bibliográficas dos artigos seleccionados, publicados entre Janeiro de 2001 e Dezembro de 2012. Conclusões: A terapêutica com um IA de terceira geração (letrozol) poderá ser considerada em jovens do sexo masculino com BEI, altura inferior a pelo menos −2,0 SDS para a idade ou previsão de altura final pelo menos 2,0 SDS abaixo da estatura média parental, desde que já tenha sido iniciada a puberdade e a idade óssea seja inferior a 14 anos. Os principais aspectos de segurança ainda sob discussão na literatura referem-se a potenciais efeitos a nível ósseo. A utilização de medicamentos off-label deve obedecer a critérios estritos de prescrição e seguimento das crianças, de forma a minimizar os riscos e obter resultados fiáveis e comparáveis. Apresenta-se proposta de sistematização de monitorização clínica, imagiológica e laboratorial, bem como critérios de término ou suspensão da mesma
The structural effects of mutations can aid in differential phenotype prediction of beta-myosin heavy chain (Myosin-7) missense variants
MOTIVATION: High-throughput sequencing platforms are increasingly used to screen patients with genetic disease for pathogenic mutations, but prediction of the effects of mutations remains challenging. Previously we developed SAAPdap (Single Amino Acid Polymorphism Data Analysis Pipeline) and SAAPpred (Single Amino Acid Polymorphism Predictor) that use a combination of rule-based structural measures to predict whether a missense genetic variant is pathogenic. Here we investigate whether the same methodology can be used to develop a differential phenotype predictor, which, once a mutation has been predicted as pathogenic, is able to distinguish between phenotypes-in this case the two major clinical phenotypes (hypertrophic cardiomyopathy, HCM, and dilated cardiomyopathy, DCM) associated with mutations in the beta-myosin heavy chain (MYH7) gene product (Myosin-7). RESULTS: A random forest predictor trained on rule-based structural analyses together with structural clustering data gave a Matthews' correlation coefficient (MCC) of 0.53 (accuracy, 75%). A post hoc removal of machine learning models that performed particularly badly, increased the performance (MCC = 0.61, Acc = 79%). This proof of concept suggests that methods used for pathogenicity prediction can be extended for use in differential phenotype prediction
Is It Possible to Simplify Risk Stratification Scores for Patients with ST-Segment Elevation Myocardial Infarction Undergoing Primary Angioplasty?
INTRODUCTION: There are several risk scores for stratification of patients with ST-segment elevation myocardial infarction (STEMI), the most widely used of which are the TIMI and GRACE scores. However, these are complex and require several variables. The aim of this study was to obtain a reduced model with fewer variables and similar predictive and discriminative ability.
METHODS: We studied 607 patients (age 62 years, SD=13; 76% male) who were admitted with STEMI and underwent successful primary angioplasty. Our endpoints were all-cause in-hospital and 30-day mortality. Considering all variables from the TIMI and GRACE risk scores, multivariate logistic regression models were fitted to the data to identify the variables that best predicted death.
RESULTS: Compared to the TIMI score, the GRACE score had better predictive and discriminative performance for in-hospital mortality, with similar results for 30-day mortality. After data modeling, the variables with highest predictive ability were age, serum creatinine, heart failure and the occurrence of cardiac arrest. The new predictive model was compared with the GRACE risk score, after internal validation using 10-fold cross validation. A similar discriminative performance was obtained and some improvement was achieved in estimates of probabilities of death (increased for patients who died and decreased for those who did not).
CONCLUSION: It is possible to simplify risk stratification scores for STEMI and primary angioplasty using only four variables (age, serum creatinine, heart failure and cardiac arrest). This simplified model maintained a good predictive and discriminative performance for short-term mortality
Intratumoral patterns of clonal evolution in gliomas
Few studies have explored the patterns of clonal evolution in gliomas. Here, we investigate the cytogenetic patterns of intratumoral clonal evolution of gliomas and their impact on tumor histopathology and patient survival. Cytogenetic analysis of 90 gliomas was performed in individual tumor cells (>200 cells/tumor) using multicolor (N = 16 probes) interphase-FISH. Overall, chromosome gains were more frequent than chromosome losses. Gains of chromosome 7 and/or EGFR amplification were detected in 91% of the cases, whereas del(9p21) (77%) and del(10q23) (78%) were the most frequent chromosome losses. Virtually, all cases (99%) showed >/=2 tumor cell clones, with higher numbers among high- versus low-grade gliomas (p = 0.001). Nine different cytogenetic patterns were found in the ancestral tumor clones. In most gliomas, ancestral clones showed abnormalities of chromosome 7, 9p, and/or 10q and cytogenetic evolution consisted of acquisition of additional abnormalities followed by tetraploidization. Conversely, early tetraploidization was associated with low-grade astrocytomas-2/3 pilocytic and 3/6 grade II diffuse astrocytomas-and combined loss of 1p36/19q13 with oligodendrogliomas, respectively; both aberrations were associated with a better patient outcome (p = 0.03). Overall, our results support the existence of different pathways of intratumoral evolution in gliomas
Effect of Time of Day on Performance, Hormonal and Metabolic Response during a 1000-M Cycling Time Trial
Introducing social sustainability aspects in supplier selection : the role of governmental intervention
This paper aims to understand how governmental intervention can drive organisations to adopt social sustainability aspects in their supplier selection process. The successful case study of the recent introduction of the In-Country-Value program at the Oil and Gas sector of Oman is examined. A survey and interviews with supply chain, contracting and procurement managers were conducted and the primary data was analysed. Governmental intervention was found capable of driving organisations to adopt social sustainability aspects in their supplier selection process, but leads to a 'cap' bounded by governmental requirements if the motivation does not come from within the organisations
Assessment of a novel, capsid-modified adenovirus with an improved vascular gene transfer profile
<p>Background: Cardiovascular disorders, including coronary artery bypass graft failure and in-stent restenosis remain significant opportunities for the advancement of novel therapeutics that target neointimal hyperplasia, a characteristic of both pathologies. Gene therapy may provide a successful approach to improve the clinical outcome of these conditions, but would benefit from the development of more efficient vectors for vascular gene delivery. The aim of this study was to assess whether a novel genetically engineered Adenovirus could be utilised to produce enhanced levels of vascular gene expression.</p>
<p>Methods: Vascular transduction capacity was assessed in primary human saphenous vein smooth muscle and endothelial cells using vectors expressing the LacZ reporter gene. The therapeutic capacity of the vectors was compared by measuring smooth muscle cell metabolic activity and migration following infection with vectors that over-express the candidate therapeutic gene tissue inhibitor of matrix metalloproteinase-3 (TIMP-3).</p>
<p>Results: Compared to Adenovirus serotype 5 (Ad5), the novel vector Ad5T*F35++ demonstrated improved binding and transduction of human vascular cells. Ad5T*F35++ mediated expression of TIMP-3 reduced smooth muscle cell metabolic activity and migration in vitro. We also demonstrated that in human serum samples pre-existing neutralising antibodies to Ad5T*F35++ were less prevalent than Ad5 neutralising antibodies.</p>
<p>Conclusions: We have developed a novel vector with improved vascular transduction and improved resistance to human serum neutralisation. This may provide a novel vector platform for human vascular gene transfer.</p>
Combined Effect of Air Pollution and House Dust Mite Exposure Over the airways
Introdução: A asma é uma doença respiratória crónica, cujo agravamento pode estar associado a factores ambientais, entre os quais os relacionados com a qualidade do ar. Objectivo: O presente trabalho pretendeu avaliar o efeito da exposição individual a poluentes atmosféricos em termos de função respiratória, num grupo de crianças com história de sibilância, entrando em consideração com o grau de infestação de ácaros do pó doméstico.
Métodos: Um grupo de 51 crianças com história de sibilância, seleccionadas através do questionário do
estudo ISAAC, foi acompanhado prospectivamente num estudo com medidas repetidas, que envolveu avaliações
médicas padronizadas que incluíram a realização de espirometria, avaliação da exposição aos ácaros do pó e cálculo
do valor de exposição individual a uma variedade de poluentes do ar: PM10, O3, NO2, benzeno, tolueno, xileno,
etilbenzeno e formaldeído. Resultados: Observou -se uma elevada percentagem de colchões com um grau de infestação de ácaros médio ou elevado. Com excepção dos valores de PM10, os valores de exposição aos poluentes do ar não alcançaram valores elevados. Na análise multivariável, tanto os poluentes (designadamente PM10, NO2, benzeno, tolueno e etilbenzeno) como o grau de infestação de ácaros do pó associaram -se a deterioração da função pulmonar. Conclusão: O presente trabalho vem reforçar o interesse da exposição aos poluentes do ar em crianças com história de sibilância, que à semelhança do que acontece com os ácaros do pó influenciam as vias aéreas
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