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1.
ACS Chem Neurosci ; 15(1): 108-118, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38099928

RESUMO

When misfolded, α-Synuclein (α-Syn), a natively disordered protein, aggregates to form amyloid fibrils responsible for the neurodegeneration observed in Parkinson's disease. Structural studies revealed distinct molecular packing of α-Syn in different fibril polymorphs and variations of interprotofilament connections in the fibrillar architecture. Fibril polymorphs have been hypothesized to exhibit diverse surface polarities depending on the folding state of the protein during aggregation; however, the spatial variation of surface polarity in amyloid fibrils remains unexplored. To map the local polarity (or hydrophobicity) along α-Syn fibrils, we visualized the spectral characteristics of two dyes with distinct polarities-hydrophilic Thioflavin T (ThT) and hydrophobic Nile red (NR)─when both are bound to α-Syn fibrils. Dual-channel fluorescence imaging reveals uneven partitioning of ThT and NR along individual fibrils, implying that relatively more polar/hydrophobic patches are spread over a few hundred nanometers. Remarkably, spectrally resolved sensitized emission imaging of α-Syn fibrils provides unambiguous evidence of energy transfer from ThT to NR, implying that dyes of dissimilar polarity are in close proximity. Furthermore, spatially resolved fluorescence spectroscopy of the solvatochromic probe NR allowed us to quantitatively map the range and variation of the polarity parameter ET30 along individual fibrils. Our results suggest the existence of interlaced polar and nonpolar nanoscale domains throughout the fibrils; however, the relative populations of these patches vary considerably over larger length scales likely due to heterogeneous packing of α-Syn during fibrilization and dissimilar exposed polarities of polymorphic segments. The employed method may provide a foundation for imaging modalities of other similar structurally unresolved systems with diverse hydrophobic-hydrophilic topology.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Amiloide/metabolismo , Doença de Parkinson/metabolismo , Imagem Óptica , Corantes
2.
Ther Innov Regul Sci ; 57(3): 402-416, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37081374

RESUMO

Clinical trials continue to be the gold standard for evaluating new medical technologies. New advancements in modern computation power have led to increasing interest in Bayesian methods. Despite the multiple benefits of Bayesian approaches, application to clinical trials has been limited. Based on insights from the survey of clinical researchers in drug development conducted by the Drug Information Association Bayesian Scientific Working Group (DIA BSWG), insufficient knowledge of Bayesian approaches was ranked as the most important perceived barrier to implementing Bayesian methods. Results of the same survey indicate that clinical researchers may find the interpretation of results from a Bayesian analysis to be more useful than conventional interpretations. In this article, we illustrate key concepts tied to Bayesian methods, starting with familiar concepts widely used in clinical practice before advancing in complexity, and use practical illustrations from clinical development.


Assuntos
Desenvolvimento de Medicamentos , Teorema de Bayes , Ensaios Clínicos como Assunto
3.
Methods Appl Fluoresc ; 10(4)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36063814

RESUMO

Excitation energy migration beyond mesoscale is of contemporary interest for both solar photovoltaic and light-emissive devices, especially in context of organometal halide perovskites (OMHPs) which have been shown to have very long (charge carrier) diffusion lengths. While understanding the energy propagation pathways in OMHPs is crucial for further advancement of material design and improvement of opto-electronic features, the simultaneous existence of multiple processes like carrier diffusion, photon recycling, and photon transport makes it often complex to differentiate them. In this study, we unravel the diverse yet dominant excitation energy transfer mode(s) in crystalline MAPbBr3micron-sized 1D rods and plates by localized (confocal) laser excitation coupled with spectrally-resolved wide-field fluorescence imaging. While rarely used, this technique can efficiently probe excitation migration beyond the diffraction limit and can be realized by simple modification of existing epifluorescence microscopy setups. We find that in rods of length below ∼2 microns, carrier diffusion dominates amongst various energy transfer processes. However, the transient non-radiative defects severely inhibit the extent of carrier migration and also temporarily affect the radiative recombination dynamics of the photo-carriers. For MAPbBr3plates of several tens of micrometers, we find that the photoluminescence (PL) spectral characteristics remain unaltered at short distances (< ∼3µm) while at a larger distance, the spectral profile is gradually red-shifted. This implies that carrier diffusion dominates over small distances, while photon recycling,i.e., repeated re-absorption and re-emission of photons, propagates excitation energy transfer over extended length scales with assistance from wave-guided photon transport. Our findings can potentially be used for future studies on the characterization of energy transport mechanisms in semiconductor solids as well as for organic (molecular) self-assembled microstructures.

4.
BMJ Open ; 12(2): e056641, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177461

RESUMO

OBJECTIVES: The MOSAIC study aimed to evaluate if the Cow's Milk-related Symptom Score (CoMiSS) can be used as a stand-alone diagnostic tool for cow's milk protein allergy (CMPA). DESIGN: Single-blinded, prospective, multicentre diagnostic accuracy study. SETTING: 10 paediatric centres in China. PARTICIPANTS: 300 non-breastfed infants (median age 16.1 weeks) with suspected CMPA. INTERVENTIONS: After performing the baseline CoMiSS, infants commenced a cow's milk protein elimination diet with amino acid-based formula for 14 days. CoMiSS was repeated at the end of the elimination trial. Infants then underwent an open oral food challenge (OFC) with cow's milk-based formula (CMF) in hospital. Infants who did not react during the OFC also completed a 14-day home challenge with CMF. A diagnosis of CMPA was made if acute or delayed reactions were reported. PRIMARY OUTCOME MEASURES: A logistic regression model for CoMiSS to predict CMPA was fitted and a receiver-operator characteristic (ROC) curve generated. An area under the curve (AUC) of ≥0.75 was deemed adequate to validate CoMiSS as a diagnostic tool (target sensitivity 80%-90% and specificity 60%-70%). RESULTS: Of 254 infants who commenced the OFC, 250 completed both challenges, and a diagnosis of CMPA made in 217 (85.4%). The median baseline CoMiSS in this group fell from 8 (IQR 5-10) to 5 (IQR 3-7) at visit 2 (p<0.000000001), with a median change of -3 (IQR -6 to -1). A baseline CoMiSS of ≥12 had a low sensitivity (20.3%), but high specificity (87.9%) and high positive predictive value (91.7%) for CMPA. The ROC analysis with an AUC of 0.67 fell short of the predefined primary endpoint. CONCLUSIONS: The present study did not support the use of CoMiSS as a stand-alone diagnostic tool for CMPA. Nevertheless, CoMiSS remains a clinically useful awareness tool to help identify infants with cow's milk-related symptoms. TRIAL REGISTRATION NUMBER: NCT03004729; Pre-results.


Assuntos
Hipersensibilidade a Leite , Alérgenos , Animais , Área Sob a Curva , Bovinos , Criança , Feminino , Humanos , Lactente , Leite , Hipersensibilidade a Leite/diagnóstico , Estudos Prospectivos
5.
Pediatr Gastroenterol Hepatol Nutr ; 24(4): 392-402, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34316474

RESUMO

PURPOSE: The present study assessed the role of an amino acid-based formula (AAF) in the growth of infants with cow's milk protein allergy (CMPA). METHODS: Non-breastfed, term infants aged 0-6 months with symptoms suggestive of CMPA were recruited from 10 pediatric centers in China. After enrollment, infants were started on AAF for two weeks, followed by an open food challenge (OFC) with cow's milk-based formula (CMF). Infants with confirmed CMPA remained on AAF until 9 months of age, in conjunction with a cow's milk protein-free complementary diet. Body weight, length, and head circumference were measured at enrollment and 9 months of age. Measurements were converted to weight-for-age, length-for-age, and head circumference-for-age Z scores (WAZ, LAZ, HCAZ), based on the World Health Organization growth reference. RESULTS: Of 254 infants (median age 16.1 weeks, 50.9% male), 218 (85.8%) were diagnosed with non-IgE-mediated CMPA, 33 (13.0%) tolerated CMF, and 3 (1.2%) did not complete the OFC. The mean WAZ decreased from 0.119 to -0.029 between birth and enrollment (p=0.067), with significant catch-up growth to 0.178 at 9 months of age (p=0.012) while being fed the AAF. There were no significant changes in LAZ (0.400 vs. 0.552; p=0.214) or HCAZ (-0.356 vs. -0.284; p=0.705) from the time of enrollment to age 9 months, suggesting normal linear and head growth velocity. CONCLUSION: The amino acid-based study formula, in conjunction with a cow's milk protein-free complementary diet, supported normal growth till 9 months of age in a cohort of Chinese infants with challenge-confirmed non-IgE-mediated CMPA.

7.
Medicine (Baltimore) ; 99(11): e19503, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32176093

RESUMO

INTRODUCTION: Post-extubation dysphagia is commonly observed in ICU patients and associated with increased aspiration rates, delayed resumption of oral intake/ malnutrition, prolonged ICU and hospital length of stay, decreased quality of life, and increased mortality. Conventional therapeutic approaches are limited. Pharyngeal electrical stimulation (PES) was previously shown to improve swallowing function and airway safety in severely dysphagic tracheostomised stroke patients. METHODS: In a multi-center, single-blind, 1:1 randomized controlled study, up to 400 (360 evaluable) mixed emergency adult ICU patients with recent extubation following mechanical ventilation and confirmed oropharyngeal dysphagia will be enrolled at investigational academic ICUs. Primary objective is to evaluate the effectiveness of PES in reducing the severity of unsafe swallows. Patients will be randomized to receive PES (or sham) treatment on 3 consecutive days in addition to best supportive care. Primary endpoint is a composite of 2 endpoints with hierarchy based on clinical priorities: DISCUSSION:: This study will evaluate the effects of PES on swallowing safety in critically ill ICU patients post mechanical ventilation with oropharyngeal dysphagia.


Assuntos
Transtornos de Deglutição/terapia , Terapia por Estimulação Elétrica , Transtornos de Deglutição/psicologia , Europa (Continente) , Humanos , Unidades de Terapia Intensiva , Estudos Prospectivos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Método Simples-Cego , Estados Unidos
8.
Clin Transl Sci ; 13(2): 337-344, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31664766

RESUMO

The purpose of this study was to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity of BOS161721, a humanized immunoglobulin G1 triple mutation (M252Y/S254T/T256E) monoclonal antibody that inhibits interleukin-21 (IL-21) bioactivity. This randomized, single-center, double-blind, placebo-controlled study randomized healthy volunteers 3:1 to single ascending intravenous and subcutaneous doses of BOS161721 (range 1-240 mg) or placebo. BOS161721 and placebo groups had similar rates of adverse events, mostly mild; none led to study discontinuation. There were no clinically significant findings in physical examination, vital signs, or laboratory assessment. In the pooled BOS161721 population, four subjects (8.5%) tested antidrug antibody-positive predose, and seven (14.9%) postdose. Absolute CD4+ lymphocyte count remained normal throughout follow-up. BOS161721 administered subcutaneously was absorbed slowly, with a median time to maximum concentration (Tmax ) of 144 hours across doses (range 1-15 days) and a mean apparent terminal elimination half-life of 80-87 days for doses ≥ 30 mg. Area under the concentration-time curve from time zero to infinity (AUC0-inf ) and maximum observed concentration (Cmax ) were linear across doses > 10 mg. Subcutaneous bioavailability was 64%. Phosphorylated signal transducer and activator of transcription 3 (pSTAT3) decreased dose-dependently with threshold characteristics at doses of ≥ 10 mg. Downregulation in BATF, IL6, LAG3, and SOCS3 genes caused by IL-21 stimulation was reversed dose-dependently. BOS161721 was well-tolerated across doses, suppressed IL-21-induced pSTAT3 dose-dependently, and reversed downregulation of genes critical to tolerance induction and T-cell exhaustion induced by IL-21. Further clinical studies are ongoing in patients with systemic lupus erythematosus, in which IL-21 has a pathogenetic role.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Tolerância Imunológica/efeitos dos fármacos , Interleucinas/antagonistas & inibidores , Adolescente , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Seguimentos , Meia-Vida , Voluntários Saudáveis , Humanos , Infusões Intravenosas , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Adulto Jovem
9.
Dysphagia ; 34(5): 698-707, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30612234

RESUMO

Oropharyngeal dysphagia is prevalent in several at-risk populations, including post-stroke patients, patients in intensive care and the elderly. Dysphagia contributes to longer hospital stays and poor outcomes, including pneumonia. Early identification of dysphagia is recommended as part of the evaluation of at-risk patients, but available bedside screening tools perform inconsistently. In this study, we developed algorithms to detect swallowing impairment using a novel accelerometer-based dysphagia detection system (DDS). A sample of 344 individuals was enrolled across seven sites in the United States. Dual-axis accelerometry signals were collected prospectively with simultaneous videofluoroscopy (VFSS) during swallows of liquid barium stimuli in thin, mildly, moderately and extremely thick consistencies. Signal processing classifiers were trained using linear discriminant analysis and 10,000 random training-test data splits. The primary objective was to develop an algorithm to detect impaired swallowing safety with thin liquids with an area under receiver operating characteristic curve (AUC) > 80% compared to the VFSS reference standard. Impaired swallowing safety was identified in 7.2% of the thin liquid boluses collected. At least one unsafe thin liquid bolus was found in 19.7% of participants, but participants did not exhibit impaired safety consistently. The DDS classifier algorithms identified participants with impaired thin liquid swallowing safety with a mean AUC of 81.5%, (sensitivity 90.4%, specificity 60.0%). Thicker consistencies were effective for reducing the frequency of penetration-aspiration. This DDS reached targeted performance goals in detecting impaired swallowing safety with thin liquids. Simultaneous measures by DDS and VFSS, as performed here, will be used for future validation studies.


Assuntos
Acelerometria/instrumentação , Algoritmos , Transtornos de Deglutição/diagnóstico , Programas de Rastreamento/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Acelerometria/métodos , Idoso , Cinerradiografia/estatística & dados numéricos , Deglutição , Análise Discriminante , Feminino , Avaliação Geriátrica , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
10.
BMJ Open ; 8(5): e019968, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29773698

RESUMO

INTRODUCTION: The symptoms of cow's milk protein allergy (CMPA) in infancy can be non-specific which may delay a correct diagnosis and cause adverse clinical outcomes. The diagnosis of non-IgE-mediated CMPA is particularly complex as it involves a 2 to 4 week elimination diet followed by oral food challenge (OFC). The Cow's Milk-related Symptom Score (CoMiSS) is a clinical resource for primary healthcare providers which aims to increase awareness of CMPA symptoms to facilitate an earlier diagnosis. The aim of the present study is to assess if the CoMiSS can be used as a potential diagnostic tool in infants with suspected CMPA. METHODS AND ANALYSIS: Exclusively formula-fed infants aged 0-6 months presenting with symptoms suggestive of CMPA will be included in this prospective, multicentre trial which will be conducted in 10 centres in China. All infants will commence a 2-week trial of an amino acid-based formula (AAF) while eliminating all cow milk protein from their diets. After the AAF treatment period, infants will undergo an open OFC in hospital with standard cow's milk formula, followed by an open home challenge for another 2 weeks. Clinical symptoms will be documented on standardised symptom scorecards. The CoMiSS will be determined at study entry (CoMiSS 1, before the start of the AAF), after 2 weeks (CoMiSS 2, before the OFC) and after a further period of 2 weeks or when symptoms suggestive of CMPA reappear (CoMiSS 3). Weight and length will be measured at each visit. The difference between CoMiSS 1 and 2 as a predictor of the OFC outcome will also be assessed. The diagnostic accuracy of the baseline CoMiSS will be calculated. ETHICS AND DISSEMINATION: The study was approved by the Hunan Children's Hospital Medical Ethics Committee, Hunan, China. The findings of this trial will be submitted for publication in a peer-reviewed journal in paediatric nutrition or gastroenterology. Abstracts will be submitted to the relevant national and international conferences. TRIAL REGISTRATION NUMBER: NCT03004729; Pre-results.


Assuntos
Alérgenos/efeitos adversos , Sistemas de Apoio a Decisões Clínicas/normas , Hipersensibilidade a Leite/diagnóstico , Alérgenos/administração & dosagem , Animais , Bovinos , Feminino , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Estudos Prospectivos , Método Simples-Cego , Estudos de Validação como Assunto
11.
J Stem Cells Regen Med ; 13(1): 29-32, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28684895

RESUMO

The Wharton's Jelly (WJ) is an established source of mesenchymal stem cells (MSC). We compared 3 methods of extracting WJ-MSC from cryopreserved tissue and determined that enzymatic digestion of the WJ yielded the most viable MSC, compared to the explant and mechanical digestion methods. The enzymatically-released WJ-MSC conformed to the International Society for Cellular Therapy (ISCT) criteria: displayed plastic-adherence, co-expressed CD73, CD90, CD105 and were negative for hematopoietic lineage cell markers.

12.
Pediatr Gastroenterol Hepatol Nutr ; 20(1): 22-26, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28401052

RESUMO

PURPOSE: The diagnosis of cow's milk (CM) allergy is a challenge. The Cow's Milk-related-Symptom-Score (CoMiSS™) was developed to offer primary health care providers a reliable diagnostic tool for CM related symptoms. The predictive prospective value of the CoMiSS™ was evaluated in three clinical trials. METHODS: Pooled analyses of the three studies were conducted based on regressing the results of the month-1 challenge test on the month-1 CoMiSS™, adjusting for baseline CoMiSS™ using a logistic regression model. In addition a logistic regression model was also fitted to the month-1 challenge test result with the change in CoMiSS™ from baseline as a predictor. RESULTS: Results suggest that infants having a low CoMiSS™ (median, 5) after 1 month dietary treatment free from intact CM protein have a significant risk of having a positive challenge test (odds ratio, 0.83; 95% confidence interval, 0.75-0.93; p=0.002). Pooled data suggest that the change in CoMiSS™ from baseline to month-1 can predict CM related symptoms as a confirmed diagnosis according to the challenge test at month-1. However, in order to validate such a tool, infants without CM related symptoms would also need to be enrolled in a validation trial. A concern is that it may not be ethical to expose healthy infants to a therapeutic formula and a challenge test. CONCLUSION: Pooled data analysis emphasizes that the CoMiSS™ has the potential to be of interest in infants suspected to have CM-related-symptoms. A prospective validation trial is needed.

13.
Sci Rep ; 6: 20795, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26883089

RESUMO

Various lines of published evidence have already demonstrated the impact of TRPV1 agonists on energetic metabolism through the stimulation of the sympathetic nervous system (SNS). This study presents a trial investigating if stimulation of the two related sensory receptors TRPA1 and TRPM8 could also stimulate the SNS and impact the energetic metabolism of healthy subjects. The trial was designed to be double-blinded, randomized, cross-over, placebo-controlled with healthy subjects and the impact on the energetic metabolism and the autonomic nervous system (ANS) of cinnamaldehyde, capsaicin and a cooling flavor was measured during the 90 min after ingestion. Energy expenditure and substrate oxidation were measured by indirect calorimetry. An exploratory method to measure ANS activity was by facial thermography and power spectral analysis of heart rate variability using ECG was also used. Following cinnamaldehyde ingestion, energy expenditure was increased as compared to placebo. Furthermore, postprandial fat oxidation was maintained higher compared to placebo after cinnamaldehyde and capsaicin ingestion. Similar peripheral thermoregulation was observed after capsaicin and cinnamaldehyde ingestion. Unlike capsaicin, the dose of cinnamaldehyde was not judged to be sensorially 'too intense' by participants suggesting that Cinnamaldehyde would be a more tolerable solution to improve thermogenesis via spicy ingredients as compared to capsaicin.


Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/metabolismo , Metabolismo Energético/efeitos dos fármacos , Canais de Potencial de Receptor Transitório/agonistas , Acroleína/análogos & derivados , Acroleína/farmacologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Canais de Cálcio , Capsaicina/farmacologia , Estudos Cross-Over , Aromatizantes/farmacologia , Voluntários Saudáveis , Frequência Cardíaca/efeitos dos fármacos , Humanos , Proteínas do Tecido Nervoso/agonistas , Oxirredução , Transdução de Sinais/efeitos dos fármacos , Canal de Cátion TRPA1 , Canais de Cátion TRPM/agonistas , Canais de Cátion TRPV/agonistas , Termografia , Adulto Jovem
14.
J Vet Cardiol ; 17(1): 1-12, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25586168

RESUMO

OBJECTIVES: To evaluate vena contracta and other echocardiographic measures of myxomatous mitral valve disease (MMVD) severity in a multivariable analysis of survival in dogs. ANIMALS: 70 dogs diagnosed with MMVD from stored echocardiographic images that met study inclusion criteria. METHODS: Left heart dimensions were measured as well as mitral regurgitant jet area/left atrial area (JAR), early mitral filling velocity (Evel), extent of mitral valve prolapse in right and left views (ProlR, ProlL), Prol indexed to aortic diameter (ProlR:Ao, ProlL:Ao), presence of a flail leaflet (FlailR, FlailL), and mitral regurgitation vena contracta diameter (VCR, VCL) indexed to aortic diameter (VCR:Ao, VCL:Ao). Follow-up from referring veterinarians was obtained by questionnaire or telephone to determine survival times. Inter- and intra-observer agreement was evaluated with Bland-Altman plots and weighted Kappa analysis. Survival was analyzed using Kaplan-Meier curves, logrank tests and Cox's proportional hazards. RESULTS: Logrank analysis showed VCL:Ao, VCR:Ao, FlailL, ProlR:Ao, ProlL:Ao, left ventricular internal dimension in diastole indexed to aortic diameter (LVIDD:Ao) >2.87, left atrium to aorta ratio (LA/Ao) >1.6, and Evel >1.4 m/s were predictors of cardiac mortality. In a multivariable analysis, the independent predictors of cardiac mortality were Evel >1.4 m/s [hazard ratio (HR) 5.0, 95% confidence interval (CI) 2.5-10.3], FlailL (HR 3.1, 95% CI 1.3-7.9), and ProlR:Ao (HR 2.8, 95% CI 1.3-6.3). CONCLUSIONS: Echocardiographic measures of mitral regurgitation severity and mitral valve pathology provide valuable prognostic information independent of chamber enlargement in dogs with MMVD.


Assuntos
Doenças do Cão/patologia , Ecocardiografia/veterinária , Insuficiência da Valva Mitral/veterinária , Animais , Biomarcadores , Cães , Feminino , Átrios do Coração/patologia , Ventrículos do Coração/patologia , Masculino , Insuficiência da Valva Mitral/patologia , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida
15.
Am J Hum Biol ; 25(6): 770-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24105777

RESUMO

BACKGROUND: A recent report suggested that human milk (HM) composition not only changes with lactation stages but also vary according to gender of the offspring. In spite of available literature, the dynamic changes of HM composition still remain to be completely explored and characterized. Progress in analytical technologies together with quantitative sampling of HM allows for a better quantification of HM nutrients and thereby providing a deeper understanding of the dynamics of HM secretion. OBJECTIVE: To characterize and quantify HM nutrients based on appropriate for analyses sampling procedures and advanced analytical methodologies. CLINICAL STUDY DESIGN: We conducted an observatory, single center, longitudinal trial with HM collection at 30, 60, and 120 days postpartum from 50 mothers (singleton-deliveries of 25 male and 25 female infants). HM samples were analyzed for lipid, lactose, energy density, fatty acids, phospholipids, and gangliosides. Longitudinal analyses of the datasets have been carried out using linear mixed models. RESULTS: HM for male infants compared to females at 120 days, were higher for energy content and lipids by 24 and 39%, respectively. Similarly, other bioactive lipids such as linoleic acid, phospholipids and gangliosides were also significantly different based on the gender of the infant. Significant stage-based differences were observed for total lipids, energy density, phospholipids, and gangliosides. Such difference in HM composition may stem from different energy needs to cope up for individual growth and development. CONCLUSION: Collectively, the current observations affirm that HM secretion, especially the lipid composition, is a very dynamic and personalized biological process.


Assuntos
Ácidos Graxos/análise , Gangliosídeos/análise , Leite Humano/química , Fosfolipídeos/análise , Adulto , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Feminino , Humanos , Lactação , Estudos Longitudinais , Masculino , Espectrometria de Massas , Período Pós-Parto , Singapura
16.
Nutr J ; 10: 139, 2011 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-22196620

RESUMO

BACKGROUND: Because the source of protein may play a role in its satiating effect, we investigated the effect of different proteins on satiation and short-term satiety. METHODS: Two randomized single-blind cross-over studies were completed. In the first study, we investigated the effect of a preload containing 20 g of casein, whey, pea protein, egg albumin or maltodextrin vs. water control on food intake 30 min later in 32 male volunteers (25 ± 4 yrs, BMI 24 ± 0.4 kg/m(2)). Subjective appetite was assessed using visual analogue scales at 10 min intervals after the preload. Capillary blood glucose was measured every 30 min during 2 hrs before and after the ad libitum meal. In the second study, we compared the effect of 20 g of casein, pea protein or whey vs. water control on satiation in 32 male volunteers (25 ± 0.6 yrs, BMI 24 ± 0.5 kg/m(2)). The preload was consumed as a starter during an ad libitum meal and food intake was measured. The preloads in both studies were in the form of a beverage. RESULTS: In the first study, food intake was significantly lower only after casein and pea protein compared to water control (P = 0.02; 0.04 respectively). Caloric compensation was 110, 103, 62, 56 and 51% after casein, pea protein, whey, albumin and maltodextrin, respectively. Feelings of satiety were significantly higher after casein and pea protein compared to other preloads (P < 0.05). Blood glucose response to the meal was significantly lower when whey protein was consumed as a preload compared to other groups (P < 0.001). In the second study, results showed no difference between preloads on ad libitum intake. Total intake was significantly higher after caloric preloads compared to water control (P < 0.05). CONCLUSION: Casein and pea protein showed a stronger effect on food intake compared to whey when consumed as a preload. However, consuming the protein preload as a starter of a meal decreased its impact on food intake as opposed to consuming it 30 min before the meal.


Assuntos
Proteínas Alimentares/administração & dosagem , Saciação/efeitos dos fármacos , Adulto , Apetite/efeitos dos fármacos , Glicemia/análise , Caseínas/administração & dosagem , Estudos Cross-Over , Ingestão de Alimentos/efeitos dos fármacos , Humanos , Masculino , Proteínas do Leite/administração & dosagem , Ovalbumina/administração & dosagem , Pisum sativum/química , Proteínas de Plantas/administração & dosagem , Polissacarídeos/administração & dosagem , Método Simples-Cego , Fatores de Tempo , Proteínas do Soro do Leite
17.
Br J Nutr ; 102(5): 722-32, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19296875

RESUMO

The present study was designed to evaluate the independent and interactive effects of a once-a-day yoghurt drink providing 2 g plant sterols/d and capsules providing 2 g fish oil n-3 long-chain (LC) PUFA/d on plasma lipids, apolipoproteins and LDL particle size. Following a 2-week run-in period, 200 mildly hypercholesterolaemic Indian adults aged 35-55 years were randomised into one of four groups of a 2 x 2 factorial, double-blind controlled trial. The 4-week treatments consisted of (1) control yoghurt drink and control capsules, (2) control yoghurt drink and fish oil capsules, (3) plant sterol-enriched yoghurt drink and control capsules, or (4) plant sterol-enriched yoghurt drink and fish oil capsules. Blood was drawn before and after the 4-week intervention. Changes in health status, lifestyle and dietary habits, and daily compliance were recorded. The main effects of plant sterols were a 4.5 % reduction in LDL-cholesterol and a 15 % reduction in TAG without a significant change in HDL-cholesterol. Overall, fish oil n-3 LC-PUFA did not significantly affect cholesterol concentrations but reduced TAG by 15 % and increased HDL-cholesterol by 5.4 %. The combination significantly lowered TAG by 15 % v. control. No significant interaction between plant sterols and n-3 LC-PUFA was observed on plasma cholesterol concentrations. In conclusion, once-a-day intake of 2 g plant sterols/d in a yoghurt drink, 2 g fish oil n-3 LC-PUFA/d in capsules, and their combination had beneficial effects on the lipid profile of mildly hypercholesterolaemic Indian adults. The potent hypotriacylglycerolaemic effect of plant sterols observed in the present study and this population warrants additional investigation.


Assuntos
Ácidos Graxos Ômega-3/uso terapêutico , Óleos de Peixe/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , Lipídeos/sangue , Fitosteróis/uso terapêutico , Adulto , Fatores Etários , Apolipoproteínas/sangue , Apolipoproteínas/efeitos dos fármacos , Cápsulas , Ingestão de Energia , Comportamento Alimentar , Feminino , Humanos , Hipercolesterolemia/sangue , Hiperlipidemias/sangue , Hiperlipidemias/psicologia , Índia , Estilo de Vida , Lipoproteínas LDL/sangue , Lipoproteínas LDL/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Reprodutibilidade dos Testes
18.
AJR Am J Roentgenol ; 190(1): 22-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18094289

RESUMO

OBJECTIVE: We performed this study to determine whether clinical, MRI, or arthroscopic findings are associated with missed lateral meniscal tears to help understand why these tears are missed on MRI. MATERIALS AND METHODS: We reviewed the medical records of 483 patients who had undergone knee MRI and arthroscopy. We assessed patient age; spontaneous or traumatic onset of knee pain; interval between pain onset and MRI; interval between MRI and arthroscopy; and arthroscopic type, size, and location of lateral meniscal tear for their association with a missed lateral meniscal tear. Each MR examination with a missed lateral meniscal tear was reviewed to determine whether the tear could be seen in retrospect. RESULTS: Thirty-six of the 189 lateral meniscal tears found at arthroscopy were not diagnosed on the original MR interpretations. There was a significant association between a missed lateral tear and a posterior horn tear or a tear involving only one third of the meniscus. There was no association between a missed lateral meniscal tear and the other variables. Review of the 36 missed tears revealed that 10 tears were visible retrospectively, six of which were longitudinal peripheral tears in the posterior horn. CONCLUSION: Lateral meniscal tears are more likely to be missed if the tear involves only one third of the meniscus or is in the posterior horn. Longitudinal peripheral tears of the posterior horn were the most commonly missed tears that could be seen in retrospect.


Assuntos
Artroscopia/estatística & dados numéricos , Erros de Diagnóstico/estatística & dados numéricos , Traumatismos do Joelho/diagnóstico , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Lesões do Menisco Tibial , Adolescente , Adulto , Reações Falso-Negativas , Feminino , Humanos , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
Neuroradiology ; 50(1): 57-65, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17899048

RESUMO

INTRODUCTION: It is claimed that bioactive coils induce accelerated and more durable aneurysm healing. Data supporting this claim are quite limited. Our purpose was to compare the angiographic and histological results obtained following treatment with different coil types. METHODS: Bifurcation type aneurysms were surgically created in 24 dogs and treated using standard clinical techniques. Eight were treated with Guglielmi detachable coils (GDC), eight with first-generation Matrix coils, and eight with a combination of GDC and Matrix coils. The aneurysms were explanted and final angiographic evaluations performed 12 weeks after treatment. Angiographic and histological outcomes were documented. RESULTS: Increased coil compaction with aneurysm recurrence was found in aneurysms treated with first-generation Matrix coils as compared to standard GDC (P = 0.0001). In aneurysms treated with first-generation Matrix coils thrombus organization was better than in those treated with either standard GDC coils (P = 0.008) or with a combination of GDC and Matrix coils (P = 0.04). In aneurysms treated with first-generation Matrix coils there were no endothelialized vascular clefts within the coil mass, but they were seen in the majority of aneurysms treated with GDC or a combination of GDC and Matrix coils (P = 0.003). CONCLUSION: Aneurysms treated with first-generation Matrix coils showed the greatest degree of coil compaction and aneurysm recurrence on the final angiographic evaluation. Aneurysms treated with first-generation Matrix coils showed enhanced thrombus organization and absence of vascular clefts at the aneurysm neck that were markedly different from those treated with bare platinum coils or a combination of GDC and Matrix coils.


Assuntos
Aneurisma Roto/terapia , Angiografia Cerebral , Embolização Terapêutica/instrumentação , Aneurisma Intracraniano/terapia , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/patologia , Animais , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Modelos Animais de Doenças , Cães , Desenho de Equipamento , Falha de Equipamento , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Recidiva
20.
J Vasc Interv Radiol ; 18(8): 1005-10, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17675619

RESUMO

PURPOSE: To compare multiple-electrode radiofrequency (RF) ablation versus RF ablation with a cluster electrode in an in vivo porcine kidney model. MATERIALS AND METHODS: Thirteen female pigs (mean weight, 45 kg) were used for the study. In each animal, RF ablations were performed for 12 minutes with a conventional cluster electrode in one kidney (controls, n = 13) and a multiple-electrode configuration in the contralateral organ. Multiple-electrode ablations were performed with electrodes 1.5 cm apart (group 1, n = 7) or 2.0 cm apart (group 2, n = 6). The mean maximum temperature at the electrode tips was determined. After each animal was euthanized, the kidneys were removed and the ablation zones were sectioned into 5-mm transverse slices. A representative slice was stained with 2,3,5-triphenyl-2H-tetrazolium chloride. Standard ablation zone metrics were measured and differences between groups were analyzed for statistical significance. RESULTS: The mean maximum ablation zone diameter was 3.0 cm +/- 0.6 (SD) for controls, compared with 5.0 cm +/- 0.5 for group 1 (P < .0001) and 4.4 cm +/- 1.0 for group 2 (P = .002). Mean ablation zone minimum diameter was higher for group 1 (P = .002) and group 2 (P = .03) than for controls. Isoperimetric ratios were lowest for group 2 (P = .04 vs controls) whereas the highest temperatures at the electrode tips were observed with group 1 (P = .02 vs controls). CONCLUSION: In normal porcine kidney, multiple-electrode RF ablation produced larger zones of ablation than a cluster electrode. Efficacy was greater when electrodes were spaced 1.5 cm apart than when they were spaced 2.0 cm apart.


Assuntos
Ablação por Cateter/instrumentação , Rim/cirurgia , Animais , Ablação por Cateter/métodos , Eletrodos Implantados , Desenho de Equipamento , Feminino , Modelos Lineares , Modelos Animais , Projetos de Pesquisa , Sus scrofa , Temperatura
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