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1.
Obes Res Clin Pract ; 17(6): 468-476, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37783586

RESUMO

BACKGROUND: Restrictions implemented by governments during the coronavirus disease 2019 (COVID-19) pandemic affected people's eating habits and physical activity. We investigated the effect of COVID-19 lockdowns and restrictions on body mass index (BMI) and weight in a UK population, according to BMI class, sex, age and ethnicity. METHODS: This retrospective observational cohort study used the Clinical Practice Research Datalink AURUM database. Baseline spanned from 22 March 2017-22 March 2020, and the follow-up lockdown period was from 23 March 2020 (start of the lockdown in the UK) to 13 March 2021. The descriptive analysis included individuals with ≥ 1 valid BMI/weight measurements during both the baseline and follow-up periods, while the model-based analysis comprised individuals with ≥ 1 valid measurement(s) during baseline. Results were stratified by baseline BMI category, sex, age and ethnicity. RESULTS: In the descriptive analysis (n = 273,529), most individuals did not change BMI category post-lockdown (66.4-83.3%). A greater proportion of women (12.6%) than men (9.5%) moved up BMI categories post-lockdown. Compared with older groups, a higher proportion of individuals < 45 years old increased post-lockdown BMI category. The model-based analysis (n = 938,150) revealed consistent trends, where changes in body weight and BMI trajectories pre- and post-lockdown were observed for women and for individuals < 45 years. CONCLUSION: During COVID-19 restrictions, women and young individuals were more likely than other groups to increase BMI category and weight post-lockdown.


Assuntos
COVID-19 , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Índice de Massa Corporal , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Estudos Retrospectivos , Obesidade/epidemiologia , Reino Unido/epidemiologia
2.
J Autism Dev Disord ; 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36547793

RESUMO

The current study investigated the utility of the Brief Observation of Social Communication Change-Phrase Speech Young Fluent (BOSCC-PSYF) as an outcome measure of treatment response by analyzing the measure's psychometric properties and initial validity. The BOSCC coding scheme was applied to 345 administrations from 160 participants diagnosed with autism. Participants included individuals of any age with phrase speech, or individuals under the age of 8 years with complex sentences. All were receiving behavioral intervention throughout the study. Test-retest and inter-rater reliability were good for the Early Communication and Social Reciprocity/Language domains, and fair for the Restricted and Repetitive Behavior domain. Significant changes occurred over time in the Early Communication and Social Reciprocity/Language domains, and Core Total scores. The BOSCC-PSYF may provide a low-cost, flexible, and user-friendly outcome measure that reliably measures changes in broad social communicative behaviors in a short period of time.

3.
Autism Res ; 15(11): 2056-2063, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36164255

RESUMO

Anecdotal reports and a small number of research studies suggest possible behavioral improvements in children with autism spectrum disorders (ASD) during a fever. However, previous studies rely largely on retrospective reports of this phenomenon. Establishing a robust association between fever and reduction of ASD-related symptoms would promote opportunities for the development of innovative therapeutic interventions for children with ASD. In the current study, prospective data were collected from 141 children with ASD and 103 typically developing (TD) controls using parent responses to an 11-item behavioral survey. Behaviors when no illness was present, during a fever, the week after a fever, and during non-febrile illnesses for TD and ASD children were compared. Profiles of cases in which caregivers reported consistent behavioral improvements during fever are described. Data indicated worsening social, emotional/behavioral, and somatic symptoms during a fever regardless of diagnosis, with children with ASD demonstrating greater worsening of behaviors during a fever than TD children. Only three out of 141 children with ASD demonstrated consistent behavioral improvements during a fever; these children had a range of cognitive and adaptive skills. Children with ASD had stronger negative responses to fever than TD children. These findings contradict previous literature suggesting behavioral improvements for children with ASD. While improvements may occur for some children, it does not appear to be a common phenomenon. Additional research is needed to elucidate the nature of behavioral improvements in the subset of children with ASD who may respond positively to fever.


Assuntos
Transtorno do Espectro Autista , Criança , Humanos , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/psicologia , Estudos Retrospectivos , Estudos Prospectivos , Emoções , Pais , Febre/complicações
4.
Autism Adulthood ; 4(2): 110-119, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36605975

RESUMO

Background: Physical and psychiatric health conditions affect the lives of many autistic adults. However, relatively little is known about individual trajectories in autistic individuals' physical and mental health from adolescence to adulthood. Methods: This study uses a well-characterized longitudinal sample (n = 253) to investigate rates of seizures, medication use, and obesity, from early adolescence (age 10 years) into adulthood (age 30 years). Within this sample, 196 participants were diagnosed with autism spectrum disorder (ASD), whereas the remaining 57 participants never received an ASD diagnosis, but, rather, were diagnosed with other neurodevelopmental conditions. Data were collected through parent report questionnaires and in-person interviews and assessments. Results: Seizure onset continued well into adulthood, with two individuals experiencing their first seizure at the age of 25 years. Seizures and neuropsychiatric medication use were both higher for those with lower intelligence quotient (IQs). In addition, medication use increased over time for these individuals, whereas those with higher IQs saw a reduction in medication use with age. Between the ages of 15 to 30 years, the predicted probability of medication use increased from 82% to 88% for those with lower IQs and decreased from 37% to 13% for those with higher IQs. Collectively, almost 70% of all participants in this study were classified as either overweight or obese. Body mass index (BMI) increased throughout adulthood, especially for those with higher IQs. The steepest increase in BMI over time occurred for those with higher IQs who also took antipsychotic medications. Conclusion: Overall, continued risk for developing seizures, high rates of neuropsychiatric medication use, and significant and increasing rates of obesity from adolescence to adulthood underscore the importance of monitoring health issues in autistic individuals and those diagnosed with other neurodevelopmental conditions throughout the lifespan.


Why was this study done?: Autistic individuals and those diagnosed with other neurodevelopmental conditions are at risk for many physical health issues from adolescence to adulthood. This includes, but is not limited to, seizure disorders, high rates of medication use, and obesity. Yet, not much longitudinal research exists measuring these health issues throughout the lifespan and, especially, in adulthood. What did the researchers do?: The researchers analyzed data from a sample of 253 individuals who lived in North Carolina, Michigan, and Illinois. This sample was recruited almost 30 years ago, beginning the study when they were roughly 2 years old. Some participants had an autism spectrum disorder diagnosis, and some did not, but instead had other neurodevelopmental conditions. The researchers measured changes in medication use, height, and weight beginning in early adolescence (age 10 years) into adulthood (age 30 years). The researchers also tracked seizure occurrences across the life span (beginning at age 2 years up until age 30 years). What were the results of the study?: In adulthood, this sample showed high rates of obesity and medication use. For example, almost 70% of this sample was classified as either overweight or obese. In addition, 55% of this sample was taking at least one neuropsychiatric medication in adulthood, and 22% of this sample was taking three different types of medication at the same time. Individuals with higher and lower intelligence quotient (IQs) had different findings over time: obesity increased throughout adulthood for those with higher IQs and medication use increased throughout adulthood for those with lower IQs. Seizures first developed for a group of individuals in adolescence and adulthood. Two individuals experienced their first seizure as late as 25 years of age. What do these findings add to what is already known?: Research, and especially longitudinal research, on physical health in autistic adults is limited. Although we know that autistic individuals generally experience high rates of obesity, seizure disorders, and medication use, less is known about how these physical health issues change over the lifespan. This study has provided useful information regarding how certain physical health issues change over time, and who these physical health issues impact the most in adulthood. How will these findings help autistic adults now or in the future?: The findings in this study identified that, in adulthood, autistic adults experience high rates of physical health issues, including increasing rates of obesity and medication use for certain populations. These findings confirm how important it is for autistic adults to have access to quality health care across the lifespan. We hope that, with these findings in mind, caregivers and health professionals will work to ensure that autistic individuals, from childhood through adolescence and adulthood, will have access and assistance in monitoring these ongoing and persistent health problems.

6.
Sci Rep ; 10(1): 11088, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632188

RESUMO

Long-standing evidence supports the importance of maintaining healthy populations of microbiota for the survival, homeostasis, and complete development of marine mollusks. However, the long-term ecological effects of agricultural runoff on these populations remains largely unknown. Atrazine (6-Chloro-n-ethyl-n'-(1-methylethyl)-triazine-2,4-diamine), a prevalent herbicide in the United States, is often used along tributaries of the Chesapeake Bay where oyster breeding programs are concentrated. To investigate any potential effects atrazine maybe having on mollusk-prokaryote interactions, we used 16S rRNA gene amplicons to evaluate how microbial compositions shift in response to exposure of environmentally relevant concentrations of atrazine previously found within the Chesapeake Bay. The dominant bacterial genera found within all groups included those belonging to Pseudoalteromonas, Burkholderia, Bacteroides, Lactobacillis, Acetobacter, Allobaculum, Ruminococcus, and Nocardia. Our results support previously published findings of a possible core microbial community in Crassostrea virginica. We also report a novel finding: oysters exposed to atrazine concentrations as low as 3 µg/L saw a significant loss of a key mutualistic microbial species and a subsequent colonization of a pathogenic bacteria Nocardia. We conclude that exposure to atrazine in the Chesapeake Bay may be contributing to a significant shift in the microbiomes of juvenile oysters that reduces fitness and impedes natural and artificial repopulation of the oyster species within the Bay.


Assuntos
Atrazina/farmacologia , Bactérias/crescimento & desenvolvimento , Crassostrea/efeitos dos fármacos , Herbicidas/farmacologia , Microbiota/efeitos dos fármacos , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Crassostrea/crescimento & desenvolvimento , Crassostrea/microbiologia , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética
7.
Future Oncol ; 16(15): 1013-1030, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32326746

RESUMO

Aim: To analyze real-world data relating to treatment decision-making in stage III-IV ovarian cancer (OC). Materials & methods: Real world data were collected from a survey of physicians and their patients (n = 2413) across Europe and the USA in 2017-2018. Results: 49% had stage IVb disease. 39, 54 and 7% of patients received first-line (1L), second-line, or 7% third-line or later treatment. In the 1L (ongoing or completed), 93% received platinum-containing regimens, 26% bevacizumab-containing regimens and 1% a PARP inhibitor-containing regimen. In 1L maintenance treatment, 81% received bevacizumab, 17% platinum-containing treatments and 6% a PARP inhibitor. Conclusion: The most common 1L treatment for advanced ovarian cancer was platinum-containing chemotherapy. Of those receiving 1L maintenance therapy, 70-99% (across countries) received targeted therapy.


Assuntos
Neoplasias Ovarianas/epidemiologia , Padrões de Prática Médica , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Terapia Combinada , Gerenciamento Clínico , Europa (Continente)/epidemiologia , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Estados Unidos/epidemiologia
8.
Future Oncol ; 15(6): 611-623, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30426780

RESUMO

AIM: To understand the treatment patterns and outcomes for stage IV squamous cell carcinoma of the head and neck, patients receiving second-line or later drug therapy. MATERIALS & METHODS: Real-world data were collected from 1152 patients in the USA, France, Germany and the UK through a retrospective chart analysis and patient-reported outcomes were collected using validated questionnaires in a subgroup of patients. RESULTS: Forty-four percent of patients had stage IVA/B disease. A total of 77, 19 and 3% of patients had received two, three and four plus lines of active drug treatment. Platinum- and cetuximab-based regimens were common at early treatment lines. Time to progression was short (5.2 months post first line), survival rates low and patient-reported health status poor. CONCLUSION: Novel therapies that could improve clinical and patient-reported outcomes would address a significant unmet need.


Assuntos
Padrões de Prática Médica , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gerenciamento Clínico , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Medidas de Resultados Relatados pelo Paciente , Retratamento , Fatores de Risco , Carcinoma de Células Escamosas de Cabeça e Pescoço/etiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Resultado do Tratamento
10.
Faraday Discuss ; 139: 35-51; discussion 105-28, 419-20, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19048989

RESUMO

Experiments that measure the viscoelasticity of single molecules from the Brownian fluctuations of an atomic force microscope (AFM) have provided a new window onto their internal dynamics in an underlying conformational landscape. Here we develop and apply these methods to examine the internal friction of unfolded polypeptide chains at high stretch. The results reveal a power law dependence of internal friction with tension (exponent 1.3 +/- 0.5) and a relaxation time approximately independent of force. To explain these results we develop a frictional worm-like chain (FWLC) model based on the Rayleigh dissipation function of a stiff chain with dynamical resistance to local bending. We analyse the dissipation rate integrated over the chain length by its Fourier components to calculate an effective tension-dependent friction constant for the end-to-end vector of the chain. The result is an internal friction that increases as a power law with tension with an exponent 3/2, consistent with experiment. Extracting the intrinsic bending friction constant of the chain it is found to be approximately 7 orders of magnitude greater than expected from solvent friction alone; a possible explanation we offer is that the underlying energy landscape for bending amino acids and/or peptide bond is rough, consistent with recent results on both proteins and polysaccharides.


Assuntos
Peptídeos/química , Elasticidade , Fricção , Viscosidade
11.
Biophys J ; 92(6): 1825-35, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17158578

RESUMO

Biological macromolecules have complex and nontrivial energy landscapes, endowing them with a unique conformational adaptability and diversity in function. Hence, understanding the processes of elasticity and dissipation at the nanoscale is important to molecular biology and emerging fields such as nanotechnology. Here we analyze single molecule fluctuations in an atomic force microscope, using a generic model of biopolymer viscoelasticity that includes local "internal" conformational dissipation. Comparing two biopolymers, dextran and cellulose (polysaccharides with and without local bistable transitions), demonstrates that signatures of simple conformational change are minima in both the elastic and internal friction constants around a characteristic force. A novel analysis of dynamics on a bistable energy landscape provides a simple explanation: an elasticity driven by the entropy, and friction by a barrier-controlled hopping time of populations between states, which is surprisingly distinct to the well-known relaxation time. This nonequilibrium microscopic analysis thus provides a means of quantifying new dynamical features of the energy landscape of the glucopyranose ring, revealing an unexpected underlying roughness and information on the shape of the barrier of the chair-boat transition in dextran. The results presented herein provide a basis toward probing the viscoelasticity of macromolecular conformational transitions on more complex energy landscapes, such as during protein folding.


Assuntos
Biopolímeros/química , Micromanipulação/métodos , Microscopia de Força Atômica/métodos , Modelos Químicos , Modelos Moleculares , Simulação por Computador , Elasticidade , Transferência de Energia , Entropia , Conformação Molecular , Estresse Mecânico , Viscosidade
12.
Chemphyschem ; 7(8): 1710-6, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-16865759

RESUMO

The viscoelastic properties of single poly(ethylene glycol) (PEG) molecules were measured by analysis of thermally and magnetically driven oscillations of an atomic force microscope (AFM) cantilever/molecule system. The molecular and monomer stiffness and friction of the PEG polymer were derived using a simple harmonic oscillator (SHO) model. Excellent agreement between the values of these two parameters obtained by the two approaches indicates the validity of the SHO model under the experimental regimes and the excellent reproducibility of the techniques. A sharp minimum in the monomeric friction is seen at around 180 pN applied force which we propose is due to a force induced change in the shape of the energy landscape describing the conformational transition of PEG from a helical to a planar state, which in turn affects the timescale of the transition and therefore modifies the measured internal friction. A knowledge of the viscoelastic response of PEG monomers is particularly important since PEG is widely used as a linker molecule for tethering groups of interest to the AFM tip in force spectroscopy experiments, and we show here that care must be exercised because of the force-dependent viscoelastic properties of these linkers.


Assuntos
Polietilenoglicóis/química , Biofísica/métodos , Físico-Química/métodos , Elasticidade , Cinética , Microscopia de Força Atômica , Modelos Estatísticos , Conformação Molecular , Oscilometria , Polímeros/química , Pressão , Estresse Mecânico , Temperatura , Termodinâmica
13.
Biophys J ; 91(2): L16-8, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16698787

RESUMO

We have applied a dynamic force modulation technique to the mechanical unfolding of a homopolymer of immunoglobulin (Ig) domains from titin, (C47S C63S I27)5, [(I27)5] to determine the viscoelastic response of single protein molecules as a function of extension. Both the stiffness and the friction of the homopolymer system show a sudden decrease when a protein domain unfolds. The decrease in measured friction suggests that the system is dominated by the internal friction of the (I27)5 molecule and not solvent friction. In the stiffness-extension spectrum we detected an abrupt feature before each unfolding event, the amplitude of which decreased with each consecutive unfolding event. We propose that these features are a clear indication of the formation of the known unfolding intermediate of I27, which has been observed previously in constant velocity unfolding experiments. This simple force modulation AFM technique promises to be a very useful addition to constant velocity experiments providing detailed viscoelastic characterization of single molecules under extension.


Assuntos
Proteínas Musculares/química , Dobramento de Proteína , Proteínas Quinases/química , Animais , Conectina , Elasticidade , Humanos , Imunoglobulinas/química , Microscopia de Força Atômica/métodos , Proteínas Musculares/ultraestrutura , Proteínas Quinases/ultraestrutura , Estrutura Terciária de Proteína/fisiologia , Viscosidade
14.
Langmuir ; 21(10): 4765-72, 2005 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-16032901

RESUMO

The dynamical nature of biomolecular systems means that knowledge of their viscoelastic behavior is important in fully understanding function. The linear viscoelastic response can be derived from an analysis of Brownian motion. However, this is a slow measurement and technically demanding for many molecular systems of interest. To address this issue, we have developed a simple method for measuring the full linear viscoelastic response of single molecules based on magnetically driven oscillations of an atomic force microscope cantilever. The cantilever oscillation frequency is periodically swept through the system resonance in less than 200 ms allowing the power spectrum to be obtained rapidly and analyzed with a suitable model. The technique has been evaluated using dextran, a polysaccharide commonly used as a test system for single molecule mechanical manipulation experiments. The monomer stiffness and friction constants were compared with those derived from other methods. Excellent agreement is obtained indicating that the new method accurately and, most importantly, rapidly provides the viscoelastic response of a single molecule between the tip and substrate. The method will be a useful tool for studying systems that change their structure and dynamic response on a time scale of 100-200 ms, such as protein folding and unfolding under applied force.


Assuntos
Biofísica/métodos , Microscopia de Força Atômica/métodos , Cobalto , Dextranos/química , Elasticidade , Magnetismo , Óptica e Fotônica , Samário , Fatores de Tempo , Viscosidade
15.
Langmuir ; 20(21): 9299-303, 2004 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-15461521

RESUMO

We report on single molecule measurements of the viscoelastic properties of the polysaccharide dextran using a new approach which involves acquiring the power spectral density of the thermal noise of an atomic force microscope cantilever while holding the single molecule of interest under force-clamp conditions. The attractiveness of this approach when compared with techniques which use forced oscillations under constant loading rate conditions is that it is a near-equilibrium measure of mechanical response which provides a more relevant probe of thermally driven biomolecular dynamics. Using a simple harmonic oscillator model of the cantilever-molecule system and by subtracting the response of the free cantilever taking into account hydrodynamic effects, the effective damping zetamol and elastic constant kmol of a single molecule are obtained. The molecular elasticity measured by this new technique shows a dependence on applied force that reflects the chair-boat conformational transition of the pyranose rings of the dextran molecule which is in good agreement with values obtained directly from the gradient of a conventional constant loading rate force-extension curve. The molecular damping is also seen to follow a nontrivial dependence on loading which we suggest indicates that it is internal friction and not work done on the solvent that is the dominant dissipative process.


Assuntos
Microscopia de Força Atômica/métodos , Polissacarídeos/química , Temperatura , Elasticidade , Oscilometria/métodos , Propriedades de Superfície , Fatores de Tempo , Viscosidade
16.
Expert Rev Mol Diagn ; 3(6): 759-68, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14628903

RESUMO

The events of September 11, 2001 revealed a need for regular monitoring of infrastructure systems. Efficient aerosol collection systems are currently in place in a variety of settings in order to sample the immediate surroundings. However, the consequence of regular monitoring is an exponential increase in the number of samples requiring rapid analysis. Automated biological agent testing systems offer a solution by providing the ability to rapidly handle large numbers of samples with fewer personnel. In addition, automated testing also offers the advantage of increased consistency and accuracy compared with human systems.


Assuntos
Automação , Bioterrorismo , Monitoramento Ambiental/métodos , Manejo de Espécimes/métodos , Guerra Biológica , Monitoramento Ambiental/instrumentação , Humanos , Reprodutibilidade dos Testes
17.
J Gen Virol ; 81(Pt 11): 2735-2739, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11038386

RESUMO

Efficacious lentiviral vaccines designed to induce cytotoxic T lymphocytes (CTL) in outbred populations with a diverse repertoire of MHC class I molecules should contain or express multiple viral proteins. To determine the equine infectious anaemia virus (EIAV) proteins with epitopes most frequently recognized by CTL from seven horses infected for 0.5 to 7 years, retroviral vector-transduced target cells expressing viral proteins were used in CTL assays. Gag p15 was recognized by CTL from 100% of these infected horses. p26 was recognized by CTL from 86%, SU and the middle third of Pol protein were each recognized by 43%, TM by 29%, and S2 by 14%. Based on these results, it is likely that a construct expressing the 359 amino acids constituting p15 and p26 would contain epitopes capable of stimulating CTL in most horses.


Assuntos
Antígenos Virais/imunologia , Epitopos/imunologia , Anemia Infecciosa Equina/imunologia , Vírus da Anemia Infecciosa Equina/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Citotoxicidade Imunológica , Cavalos/imunologia , Cavalos/virologia
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