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1.
Proc Biol Sci ; 289(1984): 20221677, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36476006

RESUMO

Carotenoid-based colour signals can be costly to produce and maintain, and trade-offs between signalling and other fitness traits are expected. In mutually ornamented species, trade-offs with reproduction may be stronger for females than males, because females often dedicate more resources to offspring production, which may lead to plastic investment in colour signals and plastic sexual dichromatism. Oestradiol is a candidate mediator of this trade-off because it regulates reproductive physiology and may also influence the expression of coloration. We tested this hypothesis by giving female common waxbills (Estrilda astrild) either oestradiol (17ß-oestradiol) or empty implants during the early breeding season and measured spectral reflectance of carotenoid-based bill coloration weekly for two months. Using a model of avian vision, we found that bill colour in oestradiol-implanted females became less saturated, less red in hue and brighter, compared with control females and with unimplanted males. This resulted in a change in bill sexual dichromatism from imperceptible to perceptible. Results support the hypothesis that female reproductive physiology influences investment in coloration through changes in oestradiol and show a form of female-driven plastic sexual dichromatism. Greater sensitivity of female colour to physiological and/or environmental conditions helps explain why differences in sexual dichromatism among species differing in ecology often evolve owing to changes in female rather than male phenotype.


Assuntos
Ecologia , Estradiol , Feminino , Masculino , Animais
2.
Rev. bras. ginecol. obstet ; 43(5): 395-402, May 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1288555

RESUMO

Abstract In a healthy athlete, the caloric intake is sufficient for sports energy needs and body physiological functions, allowing a balance between energy availability, bone metabolism, andmenstrual cycle.Onthe other hand, an imbalance causedby low energy availability dueto a restrictive diet, eating disorders or long periods of energy expenditure leads to multisystemic deregulation favoring the essential functions of the body. This phenomenon, described as the female athlete triad, occurs in a considerable percentage of high-performance athletes, with harmful consequences for their future. The present review was carried out based on a critical analysis of themost recent publications available and aims to provide a global perception of the topic relative energy deficit in sport (RED-S). The objective is to promote theacquisition ofmore consolidated knowledgeon an undervaluedtheme, enabling the acquisition of preventive strategies, early diagnosis and/or appropriate treatment.


Resumo Emumaatleta saudável, oaporte calórico é suficientepara anecessidade energética esportiva e para as funções fisiológicas corporais, permitindo um equilíbrio entre disponibilidade energética (DE), metabolismo ósseo e função menstrual. Por outro lado, um desequilíbrio devido à baixa disponibilidade energética (BDE) por dieta restritiva, perturbações alimentares ou grandes períodos de gasto energético conduz a uma desregulação multissistêmica priorizando as funções essenciais do corpo. Este fenômeno, descrito inicialmente como tríade da mulher atleta e, atualmente, comodéfice energético relativo no esporte (RED-S, nasigla eminglês) tem como pilares a BDE, disfunção menstrual e alterações na densidade mineral óssea (DMO), estando presente em uma percentagem considerável de atletas de alta competição, com consequências nefastas para o seu futuro a curto, médio e longo prazo. A presente revisão foi realizada a partir da análise crítica das publicações mais recentes disponíveis e pretende proporcionar uma percepção global do tema RED-S. O objetivo é promover a aquisição de um conhecimento mais consolidado sobre uma temática subvalorizada, possibilitando a aquisição de estratégias preventivas, diagnóstico precoce e/ou tratamento adequado.


Assuntos
Humanos , Feminino , Ingestão de Energia/fisiologia , Síndrome da Tríade da Mulher Atleta/diagnóstico , Síndrome da Tríade da Mulher Atleta/prevenção & controle , Desempenho Atlético , Deficiência Energética Relativa no Esporte , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Metabolismo Energético/fisiologia , Atletas , Amenorreia , Distúrbios Menstruais/complicações
3.
Sci Rep ; 9(1): 19942, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882777

RESUMO

Coronary CT angiography (CTA) is currently considered a reliable method to exclude obstructive coronary artery disease (CAD) before valvular heart surgery in patients with low pretest probability. However, its role in excluding obstructive CAD before transcatheter aortic valve implantation (TAVI) is less well established. Single-center retrospective study where patients with severe symptomatic aortic stenosis underwent both CTA and invasive coronary angiography (ICA) as part of TAVI planning. CTA exams were conducted on a 64-slice dual source scanner, with a median interval of 45 days to ICA (IQR 25-75 [13-82]). In both tests, obstructive CAD was defined as a ≥50% stenosis in an epicardial vessel ≥2 mm diameter. Per-patient, per-vessel and per-proximal segment analyses were conducted, excluding and including non-evaluable segments. The study included 200 patients (120 women, mean age 83 ± 6 years). The prevalence of obstructive CAD on ICA was 35.5% (n = 71). On a per-patient analysis (assuming non-evaluable segments as stenotic), CTA showed sensitivity of 100% (95% CI, 95-100%), specificity of 42% (95% CI, 33-51%), and positive and negative predictive values of 48% (95% CI, 44-51%) and 100% (95% CI, 92-100%), respectively. CTA was able to exclude obstructive CAD in 54 patients (27%), in whom ICA could have been safely withheld. Despite the high rate of inconclusive tests, pre-procedural CTA is able to safely exclude obstructive CAD in a significant proportion of patients undergoing TAVI, possibly avoiding the need for ICA in roughly one quarter of the cases.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Substituição da Valva Aórtica Transcateter/métodos , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Estenose Coronária/fisiopatologia , Feminino , Humanos , Masculino , Tomografia Computadorizada Multidetectores/métodos , Imagem de Perfusão do Miocárdio/métodos , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Rev Port Cardiol ; 34(1): 71.e1-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25577659

RESUMO

INTRODUCTION: Pregnant women with mechanical prosthetic heart valves are at increased risk for valve thrombosis. Management decisions for this life-threatening complication are complex. Open-heart surgery has a very high risk of maternal mortality and fetal loss. Bleeding and embolic risks associated with thrombolytic agents, the limited efficacy of thrombolysis in certain subgroups, and a lack of experience in the setting of pregnancy raise important concerns. CASE REPORT: We report a case of mitral prosthetic valve thrombosis in early pregnancy, which was successfully treated with streptokinase. Ten years later, the same patient had an uneventful pregnancy, throughout which acenocoumarol was maintained. CONCLUSION: With this case we review the prevention (with oral anticoagulant therapy) and treatment of prosthetic valve thrombosis during pregnancy, which is important for both obstetrician and cardiologist.


Assuntos
Anticoagulantes/uso terapêutico , Valva Mitral , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Feminino , Humanos , Gravidez , Terapia Trombolítica
6.
J Card Surg ; 29(4): 512-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24894975

RESUMO

Aortic coarctation can be repaired surgically or percutaneously. The decision should be made according to the anatomy and location of the coarctation, age of the patient, presence of other cardiac lesions, and other anatomic determinants (extensive collaterals or aortic calcification). This article reviews the different therapeutic options available, explaining the differences between children and adults, describing different approaches to the same disease, exemplified by three cases of nonclassic surgical approach and one percutaneous treatment.


Assuntos
Coartação Aórtica/cirurgia , Procedimentos Cirúrgicos Cardiovasculares/métodos , Procedimentos Endovasculares/métodos , Adolescente , Adulto , Coartação Aórtica/diagnóstico , Coartação Aórtica/etiologia , Coartação Aórtica/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Stents , Resultado do Tratamento
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