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1.
J Clin Med ; 12(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36836043

RESUMO

Congenital diaphragmatic hernia (CDH) is associated with pulmonary hypoplasia and respiratory morbidity. To assess whether respiratory morbidity during the first 2 years of life in infants with left-sided CDH is associated with fetal lung volume (FLV) evaluated by the observed-to-expected FLV ratio (o/e FLV) on antenatal magnetic resonance imaging (MRI). In this retrospective study, o/e FLV measures were collected. Respiratory morbidity in the first 2 years of life was studied according to two endpoints: treatment with inhaled corticosteroids for >3 consecutive months and hospitalization for any acute respiratory disease. The primary outcome was a favorable progression defined by the absence of either endpoint. Forty-seven patients were included. The median o/e FLV was 39% (interquartile range, 33-49). Sixteen (34%) infants were treated with inhaled corticosteroids and 13 (28%) were hospitalized. The most efficient threshold for a favorable outcome was an o/e FLV ≥ 44% with a sensitivity of 57%, specificity of 79%, negative predictive value of 56%, and positive predictive value of 80%. An o/e FLV ≥ 44% was associated with a favorable outcome in 80% of cases. These data suggest that lung volume measurement on fetal MRI may help to identify children at lower respiratory risk and improve information during pregnancy, patient characterization, decisions about treatment strategy and research, and personalized follow-up.

2.
J Chem Theory Comput ; 12(12): 6035-6048, 2016 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-27775883

RESUMO

Multistate protein design explores side chain mutations, with the backbone allowed to sample a small, predetermined library of conformations. To achieve Boltzmann sampling of sequences and conformations, we use a hybrid Monte Carlo (MC) scheme: a trial hop between backbone models is followed by a short MC segment where side chain rotamers adjust to the new backbone, before applying a Metropolis-like acceptance test. The theoretical form and a practical approximation for the acceptance test are derived. We then compute backbone conformational free energies for two SH2 and SH3 proteins using different routes and protocols, and verify that for simple test problems, the free energy behaves like a state function, a hallmark of Boltzmann sampling.


Assuntos
Proteínas/química , Domínio Catalítico , Enzimas/química , Enzimas/metabolismo , Simulação de Dinâmica Molecular , Método de Monte Carlo , Estrutura Terciária de Proteína , Proteínas/metabolismo , Termodinâmica , Domínios de Homologia de src
3.
Insights Imaging ; 5(5): 571-83, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25217150

RESUMO

UNLABELLED: Idiopathic scoliosis is one of the most common conditions encountered in paediatric practice. It is a three-dimensional (3D) spinal deformity. Conventional radiography is still the modality of choice for evaluation of children and adolescents with idiopathic scoliosis, but it requires repeat radiographs until skeletal maturity is reached and does not provide information about spinal deformity in all three planes. A biplanar X-ray device is a new technique that enables standing frontal and lateral radiographs of the spine to be obtained at lowered radiation doses. With its specific software, this novel vertical biplanar X-ray unit provides 3D images of the spine and offers the opportunity of visualising the spinal deformity in all three planes. This pictorial review presents our experience with this new imaging system in children and adolescents with idiopathic scoliosis. KEY POINTS: • The biplanar X-ray device produces two orthogonal spine X-ray images in a standing position. • The biplanar X-ray device can assess idiopathic scoliosis with a lower radiation dose. • The biplanar X-ray device provides 3D images of the spine.

4.
J Obstet Gynaecol Can ; 36(9): 822-825, 2014 Sep.
Artigo em Francês | MEDLINE | ID: mdl-25222362

RESUMO

BACKGROUND: An incarcerated uterus refers to the retroversion of a pregnant uterus within the pelvis due to the absence of a forward tilt at the end of the first trimester. An incarcerated uterus that is overlooked or only discovered perpartum can cause severe obstetrical complications. Several authors have shared their experience with uterine incarceration management at 12, 14, and 16 weeks of amenorrhea. CASE: Our report concerns a case of uterine incarceration management at 21 weeks of amenorrhea, achieved by way of a specific anesthesia protocol and the positioning of the patient, which allowed the disimpaction of the uterus with the help of external maneuvers. No recurrence was observed. CONCLUSION: Uterine incarceration management is possible beyond 16 weeks of amenorrhea.


Background: An incarcerated uterus refers to the retroversion of a pregnant uterus within the pelvis due to the absence of a forward tilt at the end of the first trimester. An incarcerated uterus that is overlooked or only discovered perpartum can cause severe obstetrical complications. Several authors have shared their experience with uterine incarceration management at 12, 14, and 16 weeks of amenorrhea. Case: Our report concerns a case of uterine incarceration management at 21 weeks of amenorrhea, achieved by way of a specific anesthesia protocol and the positioning of the patient, which allowed the disimpaction of the uterus with the help of external maneuvers. No recurrence was observed. Conclusion: Uterine incarceration management is possible beyond 16 weeks of amenorrhea.


Assuntos
Manipulações Musculoesqueléticas/métodos , Posicionamento do Paciente/métodos , Complicações na Gravidez , Propofol/administração & dosagem , Succinilcolina/administração & dosagem , Retroversão Uterina , Adulto , Anestésicos Intravenosos/administração & dosagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Fármacos Neuromusculares Despolarizantes/administração & dosagem , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/terapia , Segundo Trimestre da Gravidez , Resultado do Tratamento , Retroversão Uterina/diagnóstico , Retroversão Uterina/terapia
5.
Insights Imaging ; 4(4): 417-29, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23686748

RESUMO

BACKGROUND: Osteogenesis imperfecta (OI), commonly called "brittle bone disease", is a genetic disorder characterised by increased bone fragility and decreased bone density due to quantitative and/or qualitative abnormalities of type I collagen. Different types of OI exist, from mild to severe; they may lead to death, multiple bone fractures, skeletal deformity and short stature. METHODS: Severe cases are usually diagnosed before birth and may incite the parents to choose therapeutic abortion, whereas milder cases are much more difficult to diagnose and may be sometimes confused with non-accidental injury (NAI) ("child abuse") in young children. Whatever the degree of severity, conventional radiography still remains the mainstay in diagnosing OI. RESULTS: The prognosis of this disorder has changed in the last few years thanks to biphosphonate therapy. CONCLUSION: The aim of this pictorial review is to illustrate the radiographic manifestations of OI, including in children receiving biphosphonates, and to outline specific patterns that help differentiate OI from NAI when necessary. KEY POINTS: • The main radiographic features of OI are osteopenia, bone fractures and bone deformities. • Some radiographic features depend on the type of OI or may be encountered with biphosphonates.

7.
J Am Chem Soc ; 132(31): 10796-801, 2010 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-20681712

RESUMO

In this article, we report the formation of micelles from a tetrathiafulvalene (TTF) end-functionalized poly(N-isopropylacrylamide) (poly(NIPAM)) derivative (1). We have determined the critical aggregation concentration (CAC) and average diameter of the micelles using fluorescence spectroscopy and dynamic light scattering experiments, respectively. We have exploited the NIPAM backbone of the polymer to thermally transform the swollen hydrophilic poly(NIPAM) derivative to a more globular hydrophobic state at the lower critical solution temperature (LCST). Finally, we have shown that we can exploit the chemical oxidation and complexation properties of the TTF unit to disrupt the micelle architecture to release the hydrophobic dye Nile Red from the interior of the micelle.


Assuntos
Acrilamidas/química , Compostos Heterocíclicos/química , Polímeros/química , Resinas Acrílicas , Corantes Fluorescentes/química , Micelas , Modelos Moleculares , Estrutura Molecular , Oxazinas/química , Oxirredução , Tamanho da Partícula , Espectrometria de Fluorescência , Propriedades de Superfície , Temperatura
8.
J Thorac Imaging ; 25(1): 48-56, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20160603

RESUMO

PURPOSE: To evaluate the impact of pulmonary arterial wall distensibility on the assessment of a computed tomography (CT) score in patients with nonmassive pulmonary embolism (PE) (ie, Mastora score). MATERIALS AND METHODS: The arterial wall distensibility of five central pulmonary arteries (pulmonary artery trunk, right and left main pulmonary arteries, right and left interlobar pulmonary arteries) was studied on ECG-gated CT angiographic studies of the chest in 15 patients with no pulmonary arterial hypertension (group 1; mean pulmonary artery pressure: 17.2 mm Hg) and 9 patients with nonmassive PE (group 2), using 2D reconstructions at every 10% of the R-R interval. RESULTS: The systolic and diastolic reconstruction time windows of the examined arteries were identical in the 2 groups, obtained at 20% and 80% of the R-R interval, respectively. No statistically significant difference was observed between the mean values of the pulmonary arterial wall distensibility between the 2 groups, varying between 20.5% and 24% in group 1 and between 23.3% and 25.9% in group 2. The coefficients of variation of the average arterial surfaces were found to vary between 4.30% and 6.50% in group 1 and 4.2% and 8.4% in group 2. Except the pulmonary artery trunk in group 2, all the intraclass correlation coefficients were around 0.8 or greater than 0.8, that is the cutoff for good homogeneity of measurements. CONCLUSION: The pulmonary arterial wall systolic-diastolic distensibility does not interfere with the assessment of a CT obstruction score in the setting of nonmassive PE.


Assuntos
Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Meios de Contraste , Eletrocardiografia , Feminino , Humanos , Iohexol , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
9.
Chem Commun (Camb) ; (35): 5266-8, 2009 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-19707641

RESUMO

We describe the application of the LCST of a naphthalene-functionalised polyNIPAM derivative as a convenient, tuneable and reversible method to disrupt complex formation with CBPQT(4+) in water.

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