Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Mol Phylogenet Evol ; 195: 108068, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38554985

RESUMO

Holarctic Stylops is the largest genus of the enigmatic insect order Strepsiptera, twisted winged parasites. Members of Stylops are obligate endoparasites of Andrena mining bees and exhibit extreme sexual dimorphism typical of Strepsiptera. So far, molecular studies on Stylops have focused on questions on species delimitation. Here, we utilize the power of whole genome sequencing to infer the phylogeny of this morphologically challenging genus from thousands of loci. We use a species tree method, concatenated maximum likelihood analysis and Bayesian analysis with a relaxed clock model to reconstruct the phylogeny of 46 Stylops species, estimate divergence times, evaluate topological consistency across methods and infer the root position. Furthermore, the biogeographical history and coevolutionary patterns with host species are assessed. All methods recovered a well resolved topology with close to all nodes maximally supported and only a handful of minor topological variations. Based on the result, we find that included species can be divided into 12 species groups, seven of them including only Palaearctic species, three Nearctic and two were geographically mixed. We find a strongly supported root position between a clade formed by the spreta, thwaitesi and gwynanae species groups and the remaining species and that the sister group of Stylops is Eurystylops or Eurystylops + Kinzelbachus. Our results indicate that Stylops originated in the Western Palaearctic or Western Palaearctic and Nearctic in the early Neogene or late Paleogene, with four independent dispersal events to the Nearctic. Cophylogenetic analyses indicate that the diversification of Stylops has been shaped by both significant coevolution with the mining bee hosts and host-shifting. The well resolved and strongly supported phylogeny will provide a valuable phylogenetic basis for further studies into the fascinating world of Strepsipterans.


Assuntos
Insetos , Abelhas/genética , Animais , Filogenia , Teorema de Bayes
2.
J Nucl Med ; 64(4): 645-651, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36604185

RESUMO

Subjects with asymptomatic moderate-to-severe or severe primary mitral regurgitation are closely observed for signs of progression or symptoms requiring surgical intervention. The role of myocardial metabolic function in progression of mitral regurgitation is poorly understood. We used 11C-acetate PET to noninvasively measure myocardial mechanical external efficiency (MEE), which is the energetic ratio of external cardiac work and left ventricular (LV) oxygen consumption. Methods: Forty-seven patients in surveillance with mitral regurgitation and no or minimal symptoms prospectively underwent PET, echocardiography, and cardiac MRI on the same day. PET was used to simultaneously measure cardiac output, LV mass, and oxygen consumption to establish MEE. PET findings were compared between patients and healthy volunteers (n = 9). MEE and standard imaging indicators of regurgitation severity, LV volumes, and function were studied as predictors of time to surgical intervention. Patients were followed a median of 3.0 y (interquartile range, 2.0-3.8 y), and the endpoint was reached in 22 subjects (47%). Results: MEE in patients reaching the endpoint (23.8% ± 5.0%) was lower than in censored patients (28.5% ± 4.5%, P = 0.002) or healthy volunteers (30.1% ± 4.9%, P = 0.001). MEE with a cutoff lower than 25.7% was significantly associated with the outcome (hazard ratio, 7.5; 95% CI, 2.7-20.6; P < 0.0001) and retained independent significance when compared with standard imaging parameters. Conclusion: MEE independently predicted time to progression requiring valve surgery in patients with asymptomatic moderate-to-severe or severe primary mitral regurgitation. The study suggests that inefficient myocardial oxidative metabolism precedes clinically observed progression in mitral regurgitation.


Assuntos
Insuficiência da Valva Mitral , Humanos , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/metabolismo , Coração/diagnóstico por imagem , Miocárdio/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Acetatos/metabolismo , Função Ventricular Esquerda
3.
Eur Heart J Cardiovasc Imaging ; 23(4): 524-531, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33899077

RESUMO

AIMS: Valvular surgery has improved long-term prognosis in severe carcinoid heart disease (CaHD). Experience is limited and uncertainty remains about predictors for survival and strategy regarding single vs. double-valve surgery. The aim was to review survival and echocardiographic findings after valvular surgery for CaHD at our institution. METHODS AND RESULTS: Between 1986 and 2019, 60 consecutive patients, median age 64 years, underwent valve surgery for severe CaHD. Operations involved combined tricuspid valve replacement (TVR) and pulmonary valve replacement (PVR) in 42 cases, and TVR-only or TVR with pulmonary valvotomy (no PVR) in 18 patients. All implanted valves were bioprosthetic. Preoperative echocardiography, creatinine, NT-pro-brain natriuretic peptide (NT-pro-BNP), and 24-h urinary 5-hydroxyindoleacetic acid (5-HIAA) were obtained. 30-Day mortality was 12% (n=7), and 8% for the most recent decade 2010-2019. Median survival was 2.2 years and maximum survival 21 years. Patients undergoing combined TVR and PVR had significantly higher survival compared with operations without PVR (median 3.0 vs. 0.9 years, P = 0.02). Preoperative levels of NT-pro-BNP and 5-HIAA in the top quartile predicted poor survival. On preoperative echocardiograms, pulmonary regurgitation was severe in 51% and indeterminate in 17%. Postoperative echocardiography confirmed relatively good durability of bioprostheses, relative to the patients' limited oncological life expectancy. CONCLUSION: Valvular surgery in CaHD has an acceptable perioperative risk. Survival for combined TVR and PVR was significantly higher compared with operations without PVR. Bioprosthetic valve replacement appears to have adequate durability. Preoperative echocardiography may underestimate pulmonary pathology. Combined TVR and PVR should be considered in most patients.


Assuntos
Doença Cardíaca Carcinoide , Implante de Prótese de Valva Cardíaca , Doença Cardíaca Carcinoide/diagnóstico por imagem , Doença Cardíaca Carcinoide/cirurgia , Seguimentos , Implante de Prótese de Valva Cardíaca/métodos , Valvas Cardíacas , Humanos , Ácido Hidroxi-Indolacético , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
4.
JACC Cardiovasc Imaging ; 14(11): 2240-2253, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33865761

RESUMO

Carcinoid disease is caused by neuroendocrine tumors, most often located in the gut, and leads in approximately 20% of cases to specific, severe heart disease, most prominently affecting right-sided valves. If cardiac disease occurs, it determines the patient's prognosis more than local growth of the tumor. Surgical treatment of carcinoid-induced valve disease has been found to improve survival in observational studies. Cardiac imaging is crucial for both diagnosis and management of carcinoid heart disease; in the past, imaging was accomplished largely by echocardiography, but more recently, imaging for carcinoid heart disease has increasingly become multimodal and warrants awareness of the particular diagnostic challenges of this disease. This paper reviews the pathophysiology and manifestations of carcinoid heart disease in light of the different imaging modalities.


Assuntos
Doença Cardíaca Carcinoide , Doença Cardíaca Carcinoide/diagnóstico por imagem , Doença Cardíaca Carcinoide/cirurgia , Ecocardiografia , Humanos , Valor Preditivo dos Testes , Prognóstico
5.
Science ; 318(5858): 1913-6, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-18096805

RESUMO

Beetles represent almost one-fourth of all described species, and knowledge about their relationships and evolution adds to our understanding of biodiversity. We performed a comprehensive phylogenetic analysis of Coleoptera inferred from three genes and nearly 1900 species, representing more than 80% of the world's recognized beetle families. We defined basal relationships in the Polyphaga supergroup, which contains over 300,000 species, and established five families as the earliest branching lineages. By dating the phylogeny, we found that the success of beetles is explained neither by exceptional net diversification rates nor by a predominant role of herbivory and the Cretaceous rise of angiosperms. Instead, the pre-Cretaceous origin of more than 100 present-day lineages suggests that beetle species richness is due to high survival of lineages and sustained diversification in a variety of niches.


Assuntos
Evolução Biológica , Besouros/classificação , Besouros/genética , Filogenia , Animais , Biodiversidade , Besouros/anatomia & histologia , Besouros/fisiologia , Cycadopsida , Comportamento Alimentar , Fósseis , Genes de Insetos , Magnoliopsida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA