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1.
J Pediatr Psychol ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38960723

RESUMO

OBJECTIVE: Household chaos, defined as a lack of organization, structure, and predictability, has been linked to deleterious childhood health outcomes and may hinder attempts to initiate and maintain healthy lifestyle changes. This study examined the associations of household chaos and obesity-related health conditions in a sample of youth being treated for obesity. METHODS: Participants were 715 patients (61.8% girls; Mage = 12.3 years; 68.7% non-Hispanic Black; M% of 95th BMI %-ile = 146.9%) enrolled in a pediatric weight management clinic. Caregiver report of household chaos was measured using the Confusion, Hubbub and Order Scale (CHAOS). Physiological obesity-related comorbidities (e.g., insulin resistance, hypertension, dyslipidemia) were assessed by a medical clinician and abstracted from electronic medical records; health conditions were dichotomized as present or not present. Psychological functioning was measured with the Pediatric Symptom Checklist, a caregiver-completed mental health screen that assesses internalizing, externalizing, and attention concerns. RESULTS: The Wilcoxon rank-sum test was used to test differences in household chaos scores for each obesity-related health condition. Caregivers of youth diagnosed with hypertension and obstructive sleep apnea reported significantly lower levels of household chaos, while caregivers who reported clinical levels of psychological dysfunction reported higher levels of chaos. CONCLUSIONS: Traditional management of childhood obesity requires changes across multiple health domains (e.g., dietary, exercise, sleep), and such change may be facilitated by structure and consistency. Present findings suggest that psychological resources within pediatric weight management settings should address individual patient-level factors associated with physiological and mental health as well as household functioning.

2.
BMC Med Educ ; 23(1): 668, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710200

RESUMO

BACKGROUND: Physician decision-making skills training is a priority to improve adoption of the cerebral palsy (CP) clinical guideline and, through this, lower the age of CP diagnosis. Clinical guideline implementation aims to improve physician practice, but evaluating meaningful change is complex. Limitations in the validity evidence of evaluation instruments impact the evidence base. Validity frameworks, such as Kane's, enable a targeted process to gather evidence for instrument scores, congruent to context and purpose. Yet, application of argument-based methodology to implementation validation is rare. Key-features examination methodology has established validity evidence supporting its use to measure decision-making skills, with potential to predict performance. We aimed to apply Kane's framework to evaluate a pilot key-features examination on physician decision-making in early CP diagnosis. METHODS: Following Kane's framework, we evaluated evidence across inferences of scoring, generalisation, extrapolation and implications in a study design describing the development and pilot of a CP diagnosis key-features examination for practising physicians. If found to be valid, we proposed to use the key-feature scores as an outcome measure of decision-making post education intervention to expedite CP diagnosis and to correlate with real-world performance data to predict physician practice. RESULTS: Supporting evidence for acceptance of scoring inferences was achieved through examination development with an expert group (n = 10) and pilot results (n = 10): (1) high internal consistency (0.82); (2) acceptable mean item-discrimination (0.34); and (3) acceptable reliability of examination scorers (95.2% congruence). Decreased physician acceptance of examination time (70%) was identified as a threat and prioritised in case reduction processes. Partial acceptance of generalisation, extrapolation and implications inferences were defensible with: (1) accumulated development evidence following established key-features methodology; (2) high pilot acceptance for authenticity (90%); and (3) plausibility of assumptions of score correlation with population register data. CONCLUSIONS: Kane's approach is beneficial for prioritising sources of validity evidence alongside the iterative development of a key-features examination in the CP field. The validity argument supports scoring assumptions and use of scores as an outcome measure of physician decision-making for CP guideline education implementation interventions. Scoring evidence provides the foundation to direct future studies exploring association of key-feature scores with real-world performance.


Assuntos
Paralisia Cerebral , Médicos , Humanos , Paralisia Cerebral/diagnóstico , Reprodutibilidade dos Testes , Tomada de Decisão Clínica , Escolaridade
3.
Eur J Neurol ; 28(2): 717-725, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33043544

RESUMO

Stroke is the second leading cause of death and dependency in Europe and costs the European Union more than €30bn, yet significant gaps in the patient pathway remain and the cost-effectiveness of comprehensive stroke care to meet these needs is unknown. The European Brain Council Value of Treatment Initiative combined patient representatives, stroke experts, neurological societies and literature review to identify unmet needs in the patient pathway according to Rotterdam methodology. The cost-effectiveness of comprehensive stroke services was determined by a Markov model, using UK cost data as an exemplar and efficacy data for prevention of death and dependency from published systematic reviews and trials, expressing effectiveness as quality-adjusted life-years (QALYs). Model outcomes included total costs, total QALYs, incremental costs, incremental QALYs and the incremental cost-effectiveness ratio (ICER). Key unmet needs in the stroke patient pathway included inadequate treatment of atrial fibrillation (AF), access to neurorehabilitation and implementation of comprehensive stroke services. In the Markov model, full implementation of comprehensive stroke services was associated with a 9.8% absolute reduction in risk of death of dependency, at an intervention cost of £9566 versus £6640 for standard care, and long-term care costs of £35 169 per 5.1251 QALYS vs. £32 347.40 per 4.5853 QALYs, resulting in an ICER of £5227.89. Results were robust in one-way and probabilistic sensitivity analyses. Implementation of comprehensive stroke services is a cost-effective approach to meet unmet needs in the stroke patient pathway, to improve acute stroke care and support better treatment of AF and access to neurorehabilitation.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Análise Custo-Benefício , Europa (Continente) , Humanos , Cadeias de Markov , Anos de Vida Ajustados por Qualidade de Vida , Acidente Vascular Cerebral/terapia
4.
BMC Pediatr ; 21(1): 416, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551757

RESUMO

BACKGROUND: This study evaluates implementation of an orientation session to address a waitlist of more than 2000 referrals to a pediatric weight management clinic in the Mid-South United States. METHODS: An hour-long group-based orientation to the pediatric weight management clinic was implemented to provide information about the structure and expectations of the clinic as well as education on healthy lifestyle recommendations. Families were contacted from the waitlist by telephone and invited to attend an orientation session prior to scheduling a clinic appointment. RESULTS: Of 2251 patients contacted from the waitlist, 768 scheduled an orientation session, of which 264 (34 %) attended. Of the 264 orientation participants, 246 (93 %) scheduled a clinic appointment. Of those, 193 (79 %) completed a clinic visit. Waitlist times decreased from 297.8 ± 219.4 days prior to implementation of orientation sessions to 104.1 ± 219.4 days after. CONCLUSIONS: Orientation has been an effective and efficient way to triage patient referrals while maximizing attendance in limited clinic slots for patients and families demonstrating interest and motivation. Elements of this approach are likely generalizable to other pediatric clinical settings that must strategically manage a large volume of patient referrals.


Assuntos
Instituições de Assistência Ambulatorial , Agendamento de Consultas , Assistência Ambulatorial , Criança , Humanos , Motivação , Encaminhamento e Consulta , Estados Unidos
5.
Gen Comp Endocrinol ; 288: 113372, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31866306

RESUMO

Reproduction is energetically expensive and investing in this life history trait is likely accompanied by significant changes in physiological activity. Investment strategy necessary for achieving reproductive success in reptiles can vary with reproductive form and pattern, potentiating different consequences for competing fitness-related traits such as those key to survival. The goal of this study was to assess if and how energetic state (i.e., energy metabolites) and self-maintenance (i.e., immunocompetence) are hormonally modulated across reproductive contexts in an oviparous, parthenogenetic lizard, the Colorado Checkered Whiptail Aspidoscelis neotesselata. Here blood plasma samples were collected from lizards within the US Army Fort Carson Military Installation near Colorado Springs, CO, USA, during seasons of reproductive activity (i.e., June) and inactivity (i.e., August). Measures of reproductive (i.e., estradiol) and energy-mobilizing (i.e., corticosterone) hormones, energy metabolites (i.e., glucose, triglycerides, and free glycerol), and innate immunity (i.e., bactericidal ability) were compared by season and reproductive stage. Levels of energy metabolites and bactericidal ability were compared to levels of E2 and CORT. Bactericidal ability was also compared to levels of energy metabolites. Corticosterone and glucose levels were lower during the reproductive season while triglyceride levels and bactericidal ability were higher, but both estradiol and free glycerol levels did not differ between seasons. Throughout vitellogenesis, corticosterone and glucose levels as well as bactericidal ability did not differ, but estradiol levels were higher during early and mid-stage and both triglyceride and free glycerol levels were lower during gravidity. Corticosterone levels were negatively associated with circulating triglycerides and bactericidal ability, but were not related to glucose nor free glycerol levels. Estradiol levels were positively associated with free glycerol levels and bactericidal ability, but were not related to glucose nor triglyceride levels. Finally, bactericidal ability was negatively associated with glucose, but positively associated with triglycerides. Differences in energetic state and immunocompetence are thus reflected by shifts in hormone secretion across reproductive investment. These findings provide partial support for the hypothesis that energetic state is differentially regulated by steroid hormones to afford reproduction, potentially at the cost of future survival.


Assuntos
Metabolismo Energético/fisiologia , Hormônios Esteroides Gonadais/metabolismo , Imunocompetência/fisiologia , Lagartos/fisiologia , Reprodução/fisiologia , Animais , Corticosterona/sangue , Estradiol/sangue , Feminino , Lagartos/metabolismo , Masculino , Oviparidade/fisiologia , Partenogênese/fisiologia , Estações do Ano , Vitelogênese/fisiologia
6.
Anaesthesia ; 75(8): 1070-1075, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31872422

RESUMO

Laryngeal surgery requires a shared airway and close collaboration between surgeon and anaesthetist in order to optimise operating conditions. Apnoeic oxygenation uses the principle of aventilatory mass flow to maintain oxygenation of pulmonary capillary blood under apnoeic conditions while minimising laryngeal movement. Concerns regarding accumulation of carbon dioxide and resultant acidaemia have limited the use of the technique. We performed a prospective study of low-flow apnoeic oxygenation for patients undergoing microlaryngoscopy under general anaesthesia in order to evaluate the ability of the technique to maintain oxygenation and determine the resultant rate of carbon dioxide accumulation. Sixty-four patients undergoing microlaryngoscopy under general anaesthesia were studied between November 2016 and December 2018. Intra-operative oxygenation was provided via a 10-French oxygen catheter placed into the trachea delivering oxygen at 0.5-1.0 l.min-1 . Data regarding apnoea time, peripheral oxygen saturation and venous blood gas concentrations were recorded. The mean (SD) duration of apnoea was 18.7 (7.2) min. Apnoeic oxygenation allowed successful completion of the surgical procedure in 62/64 patients. Mean (SD) rate of rise of the venous partial pressure of carbon dioxide was 0.15 (0.10) kPa.min-1 . Operating conditions were recorded qualitatively as being adequate in all cases. No adverse effects were reported. Low-flow intra-tracheal apnoeic oxygenation is a simple, effective and inexpensive technique to maintain oxygenation for laryngeal surgery.


Assuntos
Manuseio das Vias Aéreas/métodos , Apneia , Laringe/cirurgia , Oxigenoterapia/métodos , Adulto , Idoso , Anestesia Geral , Gasometria , Dióxido de Carbono/sangue , Feminino , Humanos , Cuidados Intraoperatórios , Laringoscopia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Troca Gasosa Pulmonar
7.
Anaesthesia ; 75(2): 171-178, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31646623

RESUMO

Free nicotine patches may promote pre-operative smoking cessation. Smokers (≥ 10 cigarettes.day-1 ) awaiting non-urgent surgery were randomly assigned (3:1) to an offer of free nicotine patches or a control group who were not offered free nicotine patches. The suggested regimen lasted 5 weeks, with patch strength decreasing incrementally after 3 and 4 weeks. The primary outcome was smoking abstinence for ≥ 4 weeks, as self-reported by participants on the day of surgery, including, where possible, corroboration using exhaled carbon monoxide testing. Out of 600 included smokers, 447 (74.5%) were randomly assigned to an offer of pre-operative nicotine patches, with 175 (39.1%) of these accepting the offer and 56 (12.5%) using patches for ≥ 3 weeks. Out of 396 participants offered nicotine patches who were included for analysis, 36 (9.1%) quit smoking for ≥ 4 weeks before surgery as compared with 8 (5.9%) controls, OR 1.5 [95%CI 0.7-3.2], p = 0.300. Sixty-three (15.9%) quit smoking for 24 h before surgery as compared with 15 (11.1%) controls, OR 1.4 [95%CI 0.8-2.4], p = 0.200. Participants offered nicotine patches were more likely to engage in a cessation attempt lasting more than 24 h, 46 (11.6%) vs. 5 (3.7%), OR 3.4 [95%CI 1.8-8.8], p = 0.010. Out of 78 participants who quit smoking by the day of surgery and were followed up at 6 months, 46 (59%) had relapsed. Offering free nicotine patches stimulated interest in quitting compared with controls, but our protocol had limited effectiveness.


Assuntos
Procedimentos Cirúrgicos Eletivos , Cuidados Pré-Operatórios/métodos , Abandono do Hábito de Fumar/métodos , Abandono do Hábito de Fumar/estatística & dados numéricos , Fumar/terapia , Dispositivos para o Abandono do Uso de Tabaco , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
8.
Behav Med ; 46(2): 92-99, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30726172

RESUMO

Youth with obesity are more likely than normal-weight peers to experience psychosocial problems. Empirically-based recommendations for addressing pediatric obesity include intensive interdisciplinary weight management comprising medical, behavioral health, nutrition, and exercise components. The present study examined changes in psychosocial functioning associated with frequency of participation in an interdisciplinary pediatric weight management program. Participants were 86 patients (55.8% females; median age = 11.5 years; 67.4% Non-Hispanic Black; median BMI percentile = 99.5) enrolled in an interdisciplinary pediatric weight management program for at least one year. Psychosocial functioning was measured with the Pediatric Symptom Checklist (PSC-17), a caregiver-completed mental health screen that assesses internalizing, externalizing, and attention difficulties as well as global functioning. The PSC-17 was completed at the initial clinic visit (baseline) and repeated one-year later (annual). The Wilcoxon Signed Rank test indicated that annual PSC-17 scores were significantly lower than baseline scores across all domains. Spearman correlation coefficients revealed no significant association between total number of clinic visits and PSC-17 global or subscale scores. However, the number of visits for exercise-only sessions was significantly correlated with caregiver-reported improvement in internalizing behaviors. Findings suggest that participation in interdisciplinary pediatric weight management may improve psychosocial functioning in youth with obesity and that attending supervised exercise sessions may be especially beneficial for improving internalizing behavior symptoms.


Assuntos
Terapia Comportamental , Terapia por Exercício , Terapia Nutricional , Manejo da Obesidade/métodos , Obesidade Infantil/terapia , Funcionamento Psicossocial , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Equipe de Assistência ao Paciente , Obesidade Infantil/psicologia , Adulto Jovem
9.
Ultrasound Obstet Gynecol ; 54(1): 72-78, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30318830

RESUMO

OBJECTIVE: To assess the impact of maternal ethnicity on the risk of adverse perinatal outcome in pregnant women with chronic hypertension. METHODS: Demographic and delivery data were collated of women with chronic hypertension and singleton pregnancy who delivered at one of three UK obstetric units between 2000 and 2014. Multivariable logistic regression models were used to calculate risk ratios (RR), according to ethnic group, for adverse perinatal outcome, adjusted for other maternal characteristics including age, parity, body mass index, smoking status, deprivation index and year of delivery. The impact of maternal ethnicity on birth-weight centile calculation was investigated by comparing the birth-weight centile chart customized for ethnicity (Gestation Related Optimal Weight; GROW) with a birth-weight centile calculator that does not adjust for that factor (INTERGROWTH-21st ). RESULTS: The study cohort included 4481 pregnancies (4045 women) with chronic hypertension. Women of white ethnicity accounted for 47% (n = 2122) of the cohort and 36% (n = 1601) were of black, 8.5% (n = 379) of Asian and 8.5% (n = 379) of other ethnicity. The overall incidence of stillbirth was 1.6%, that of preterm birth < 37 weeks was 16% and that of fetal growth restriction (birth weight < 3rd centile) was 11%. Black women, compared with white women, had the highest risk for all adverse perinatal outcomes, with stillbirth occurring in 3.1% vs 0.6% of pregnancies (adjusted RR (aRR), 5.56 (95% CI, 2.79-11.09)), preterm birth < 37 weeks in 21% vs 11% (aRR, 1.70 (95% CI, 1.43-2.01)) and birth weight < 3rd centile in 15% vs 7.4% (aRR, 2.07 (95% CI, 1.71-2.51)). Asian women, compared with white women, were also at increased risk of adverse perinatal outcome, with stillbirth occurring in 1.6% vs 0.6% (aRR, 3.03 (95% CI, 1.11-8.28)), preterm birth < 37 weeks in 20% vs 11% (aRR, 1.82 (95% CI, 1.41-2.35)) and birth weight < 3rd centile in 12% vs 7.4% (aRR, 1.69 (95% CI, 1.24-2.30)). The sensitivity and specificity for prediction of infants requiring neonatal unit admission were 40% and 93%, respectively, for those with birth weight < 3rd centile according to GROW charts, compared with 16% and 96%, respectively, for those with birth weight < 3rd centile according to INTERGROWTH-21st charts. CONCLUSIONS: Black ethnicity, compared with white, is associated with the greatest risk of adverse perinatal outcome in women with chronic hypertension, even after adjusting for other maternal characteristics. Women of Asian ethnicity are also at increased risk, but to a lesser extent. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Hipertensão/complicações , Resultado da Gravidez/epidemiologia , Natimorto/epidemiologia , Adulto , Peso ao Nascer , Doença Crônica , Etnicidade , Feminino , Morte Fetal , Retardo do Crescimento Fetal/epidemiologia , Humanos , Hipertensão/diagnóstico , Hipertensão/etnologia , Hipertensão/fisiopatologia , Incidência , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Paridade , Gravidez , Reino Unido/epidemiologia
10.
Nature ; 501(7468): 501-5, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24067709

RESUMO

The heat transport and lithospheric dynamics of early Earth are currently explained by plate tectonic and vertical tectonic models, but these do not offer a global synthesis consistent with the geologic record. Here we use numerical simulations and comparison with the geologic record to explore a heat-pipe model in which volcanism dominates surface heat transport. These simulations indicate that a cold and thick lithosphere developed as a result of frequent volcanic eruptions that advected surface materials downwards. Declining heat sources over time led to an abrupt transition to plate tectonics. Consistent with model predictions, the geologic record shows rapid volcanic resurfacing, contractional deformation, a low geothermal gradient across the bulk of the lithosphere and a rapid decrease in heat-pipe volcanism after initiation of plate tectonics. The heat-pipe Earth model therefore offers a coherent geodynamic framework in which to explore the evolution of our planet before the onset of plate tectonics.

11.
Phys Rev Lett ; 121(18): 180501, 2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30444422

RESUMO

Constructing a large-scale ion trap quantum processor will require entangling gate operations that are robust in the presence of noise and experimental imperfection. We experimentally demonstrate how a new type of Mølmer-Sørensen gate protects against infidelity caused by heating of the motional mode used during the gate. Furthermore, we show how the same technique simultaneously provides significant protection against slow fluctuations and mis-sets in the secular frequency. Since this parameter sensitivity is worsened in cases where the ions are not ground-state cooled, our method provides a path towards relaxing ion cooling requirements in practical realizations of quantum computing and simulation.

12.
J Strength Cond Res ; 32(3): 610-616, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29189586

RESUMO

Swearingen, JT, Weiss, LW, Smith, WA, Stephenson, MD, and Schilling, BK. Potential utility of a loaded treadmill protocol for tactical athletes. J Strength Cond Res 32(3): 610-616, 2018-Aerobic capacity is an important variable for tactical athletes, with V[Combining Dot Above]O2max being the most direct way of estimating it in a laboratory setting. A mode-specific protocol involving fixed-weight, torso-borne loads was assessed in the current study. On 4 separate days, 15 men (age 22.1 ± 2.7 years, mass 85.1 ± 10.6 kg, height 179.0 ± 7.7 cm) performed a weighted treadmill walking protocol (2 trials) and a nonweighted treadmill running protocol (2 trials). Both the weighted and nonweighted protocols were reliable, with intraclass correlation coefficient values of 0.79 and 0.87, respectively. V[Combining Dot Above]O2peak values from both protocols were highly correlated (r = 0.90, p < 0.01). However, V[Combining Dot Above]O2peak was higher during the nonweighted protocol (t = 7.547, d = 2.47, p < 0.01). Work rate was calculated for both the last completed stage and stage during which participants reached fatigue. Work rates for both protocols on the last completed stage were similar (t = 1.44, d = 0.83, p = 0.17), although the work rate for the final attempted stage was greater for the weighted-walking protocol (t = 5.85, d = 3.60, p < 0.01). These data suggest a weighted-walking V[Combining Dot Above]O2peak that is highly associated with a running V[Combining Dot Above]O2peak. This test may be applied to those who routinely perform torso-borne load carriage, such as tactical athletes. Future weighted-walking protocols should seek achieve higher resolution, especially near the end stage of the test where subjects reach volitional fatigue. Large increases in work rate may not be feasible at the end stages of the test.


Assuntos
Tolerância ao Exercício/fisiologia , Consumo de Oxigênio/fisiologia , Caminhada/fisiologia , Suporte de Carga/fisiologia , Adolescente , Adulto , Atletas , Teste de Esforço , Fadiga , Humanos , Masculino , Militares , Adulto Jovem
13.
Pharmacogenomics J ; 17(2): 137-145, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-26856248

RESUMO

Variation in the expression level and activity of genes involved in drug disposition and action ('pharmacogenes') can affect drug response and toxicity, especially when in tissues of pharmacological importance. Previous studies have relied primarily on microarrays to understand gene expression differences, or have focused on a single tissue or small number of samples. The goal of this study was to use RNA-sequencing (RNA-seq) to determine the expression levels and alternative splicing of 389 Pharmacogenomics Research Network pharmacogenes across four tissues (liver, kidney, heart and adipose) and lymphoblastoid cell lines, which are used widely in pharmacogenomics studies. Analysis of RNA-seq data from 139 different individuals across the 5 tissues (20-45 individuals per tissue type) revealed substantial variation in both expression levels and splicing across samples and tissue types. Comparison with GTEx data yielded a consistent picture. This in-depth exploration also revealed 183 splicing events in pharmacogenes that were previously not annotated. Overall, this study serves as a rich resource for the research community to inform biomarker and drug discovery and use.


Assuntos
Processamento Alternativo , Biologia Computacional , Sequenciamento de Nucleotídeos em Larga Escala , Farmacogenética , Variantes Farmacogenômicos , Análise de Sequência de RNA , Transcriptoma , Tecido Adiposo/metabolismo , Linhagem Celular , Bases de Dados Genéticas , Genótipo , Humanos , Rim/metabolismo , Fígado/metabolismo , Miocárdio/metabolismo , Fenótipo
14.
NMR Biomed ; 30(1)2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27859827

RESUMO

Quantitative MRI and MRS are increasingly important as non-invasive outcome measures in therapy development for Duchenne muscular dystrophy (DMD). Many studies have focussed on individual measures such as fat fraction and metabolite levels in relation to age and functionality, but much less attention has been given to how these indices relate to each other. Here, we assessed spatially resolved metabolic changes in leg muscles of DMD patients, and classified muscles according to the degree of fat replacement compared with healthy controls. Quantitative MRI (three-point Dixon and multi-spin echo without fat suppression and a tri-exponential fit) and 2D-CSI 31 P MRS scans were obtained from 18 DMD patients and 12 healthy controls using a 3 T and a 7 T MR scanner. Metabolite levels, T2 values and fat fraction were individually assessed for five lower leg muscles. In muscles with extensive fat replacement, phosphodiester over adenosine triphosphate (PDE/ATP), inorganic phosphate over phosphocreatine, intracellular tissue pH and T2 were significantly increased compared with healthy controls. In contrast, in muscles without extensive fat replacement, only PDE/ATP and T2 values were significantly elevated. Overall, our results show that PDE levels and T2 values increase prior to the occurrence of fat replacement and remain elevated in later stages of the disease. This suggests that these individual measures could not only function as early markers for muscle damage but also reflect potentially reversible pathology in the more advanced stages.


Assuntos
Trifosfato de Adenosina/metabolismo , Tecido Adiposo/patologia , Imageamento por Ressonância Magnética/métodos , Imagem Molecular/métodos , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/metabolismo , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/diagnóstico , Fósforo/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Ann Oncol ; 27(5): 880-6, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26802156

RESUMO

BACKGROUND: Preclinical work suggests SRC proteins have a role in the development of resistance to vascular endothelial growth factor (VEGF) targeted therapy in metastatic clear-cell renal cancer (mRCC). This hypothesis was tested in this trial using the SRC inhibitor saracatinib and the VEGF inhibitor cediranib. PATIENTS AND METHODS: Patients with disease progression after ≥1 VEGF-targeted therapy were eligible to participate in this double-blind, randomized (1:1) phase II study. The study compared the combination cediranib 30 mg once daily (o.d.) and saracatinib 175 mg o.d. (CS) (n = 69) or cediranib 45 mg o.d. and placebo o.d. (C) (n = 69). Archived tissue was used for biomarker analysis [SRC, focal adhesion kinase (FAK), von Hippel-Lindau, protein tyrosine phosphatase 1b and hypoxia-inducible factor 2α : n = 86]. The primary end point was progression-free survival (PFS) by RECIST v1.1. RESULTS: Between 2010 and 2012, 138 patients were randomized across 16 UK sites. The characteristics of the two groups were well balanced. Partial responses were seen in 13.0% for C and 14.5% for CS (P > 0.05). There was no significant difference in PFS [5.4 months (3.6-7.3 months) for C and 3.9 (2.4-5.3 months) for CS; hazard ratio (HR) 1.18 (0.94-1.48)] or overall survival (OS) [14.2 months (11.2-16.8 months) for C and 10.0 (6.7-13.2 months) for CS; HR 1.28 (1.00-1.63)]. There was no significant difference in the frequency of key adverse events, dose reductions or drug discontinuations. None of the biomarkers were prognostic for PFS or OS. FAK overexpression correlated with an OS benefit [HR 2.29 (1.09-4.82), P > 0.05], but not PFS, for CS. CONCLUSIONS: Saracatinib did not increase the efficacy of a VEGF-targeted therapy (cediranib) in this setting. Biomarker analysis did not identify consistent predictive biomarkers. CLINICALTRIALSGOV: NCT00942877.


Assuntos
Benzodioxóis/administração & dosagem , Carcinoma de Células Renais/tratamento farmacológico , Quinazolinas/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Modelos de Riscos Proporcionais , Fator A de Crescimento do Endotélio Vascular/genética
16.
J Intern Med ; 279(4): 315-36, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26522443

RESUMO

Nitric oxide (NO) is generated endogenously by NO synthases to regulate a number of physiological processes including cardiovascular and metabolic functions. A decrease in the production and bioavailability of NO is a hallmark of many major chronic diseases including hypertension, ischaemia-reperfusion injury, atherosclerosis and diabetes. This NO deficiency is mainly caused by dysfunctional NO synthases and increased scavenging of NO by the formation of reactive oxygen species. Inorganic nitrate and nitrite are emerging as substrates for in vivo NO synthase-independent formation of NO bioactivity. These anions are oxidation products of endogenous NO generation and are also present in the diet, with green leafy vegetables having a high nitrate content. The effects of nitrate and nitrite are diverse and include vasodilatation, improved endothelial function, enhanced mitochondrial efficiency and reduced generation of reactive oxygen species. Administration of nitrate or nitrite in animal models of cardiovascular disease shows promising results, and clinical trials are currently ongoing to investigate the therapeutic potential of nitrate and nitrite in hypertension, pulmonary hypertension, peripheral artery disease and myocardial infarction. In addition, the nutritional aspects of the nitrate-nitrite-NO pathway are interesting as diets suggested to protect against cardiovascular disease, such as the Mediterranean diet, are especially high in nitrate. Here, we discuss the potential therapeutic opportunities for nitrate and nitrite in prevention and treatment of cardiovascular and metabolic diseases.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Doenças Metabólicas/tratamento farmacológico , Nitratos/uso terapêutico , Nitritos/uso terapêutico , Animais , Disponibilidade Biológica , Pressão Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/prevenção & controle , Sistema Cardiovascular/efeitos dos fármacos , Modelos Animais de Doenças , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Doenças Metabólicas/prevenção & controle , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/metabolismo , Nitratos/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/biossíntese , Nitritos/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Vasodilatação/efeitos dos fármacos
17.
NMR Biomed ; 29(9): 1305-15, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-25974894

RESUMO

In this article we present our projections of future hardware developments on 7 T human MRI systems. These include compact cryogen-light magnets, improved gradient performance, integrated RF-receive and direct current shimming coil arrays, new RF technology with adaptive impedance matching, patient-specific specific absorption rate estimation and monitoring, and increased integration of physiological monitoring systems. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Aumento da Imagem/instrumentação , Imageamento por Ressonância Magnética/instrumentação , Imãs , Processamento de Sinais Assistido por Computador/instrumentação , Transdutores , Animais , Desenho de Equipamento/métodos , Desenho de Equipamento/tendências , Previsões , Humanos , Imageamento por Ressonância Magnética/tendências , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Phys Rev Lett ; 117(22): 220501, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27925715

RESUMO

Trapped ions are a promising tool for building a large-scale quantum computer. However, the number of required radiation fields for the realization of quantum gates in any proposed ion-based architecture scales with the number of ions within the quantum computer, posing a major obstacle when imagining a device with millions of ions. Here, we present a fundamentally different approach for trapped-ion quantum computing where this detrimental scaling vanishes. The method is based on individually controlled voltages applied to each logic gate location to facilitate the actual gate operation analogous to a traditional transistor architecture within a classical computer processor. To demonstrate the key principle of this approach we implement a versatile quantum gate method based on long-wavelength radiation and use this method to generate a maximally entangled state of two quantum engineered clock qubits with fidelity 0.985(12). This quantum gate also constitutes a simple-to-implement tool for quantum metrology, sensing, and simulation.

19.
Br J Dermatol ; 175(6): 1320-1328, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27411377

RESUMO

BACKGROUND: The concurrent impact of repeated low-level summer sunlight exposures on vitamin D production and cutaneous DNA damage, potentially leading to mutagenesis and skin cancer, is unknown. OBJECTIVES: This is an experimental study (i) to determine the dual impact of repeated low-level sunlight exposures on vitamin D status and DNA damage/repair (via both skin and urinary biomarkers) in light-skinned adults; and (ii) to compare outcomes following the same exposures in brown-skinned adults. METHODS: Ten white (phototype II) and six South Asian volunteers (phototype V), aged 23-59 years, received 6 weeks' simulated summer sunlight exposures (95% ultraviolet A/5% ultraviolet B, 1·3 standard erythemal doses three times weekly) wearing summer clothing exposing ~35% body surface area. Assessments made were circulating 25-hydroxyvitamin D [25(OH)D], immunohistochemistry for cyclobutane pyrimidine dimer (CPD)-positive nuclei and urinary biomarkers of direct and oxidative (8-oxo-deoxyguanosine) DNA damage. RESULTS: Serum 25(OH)D rose from mean 36·5 ± 13·0 to 54·3 ± 10·5 nmol L-1 (14·6 ± 5·2 to 21·7 ± 4·2 ng mL-1 ) in phototype II vs. 17·2 ± 6·3 to 25·5 ± 9·5 nmol L-1 (6·9 ± 2·5 to 10·2 ± 3·8 ng mL-1 ) in phototype V (P < 0·05). Phototype II skin showed CPD-positive nuclei immediately postcourse, mean 44% (range 27-84) cleared after 24 h, contrasting with minimal DNA damage and full clearance in phototype V (P < 0·001). The findings did not differ from those following single ultraviolet radiation (UVR) exposure. Urinary CPDs remained below the detection threshold in both groups; 8-oxo-deoxyguanosine was higher in phototype II than V (P = 0·002), but was unaffected by UVR. CONCLUSIONS: Low-dose summer sunlight exposures confer vitamin D sufficiency in light-skinned people concurrently with low-level, nonaccumulating DNA damage. The same exposures produce minimal DNA damage but less vitamin D in brown-skinned people. This informs tailoring of sun-exposure policies.


Assuntos
Dano ao DNA/efeitos da radiação , Estações do Ano , Luz Solar , Vitamina D/biossíntese , 8-Hidroxi-2'-Desoxiguanosina , Adolescente , Adulto , Sudeste Asiático/etnologia , Biomarcadores/sangue , Biomarcadores/urina , Reparo do DNA/fisiologia , Reparo do DNA/efeitos da radiação , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Dieta , Exposição Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dímeros de Pirimidina/urina , Pele/metabolismo , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/urina , Pigmentação da Pele/efeitos da radiação , Vitamina D/administração & dosagem , Vitamina D/análogos & derivados , Vitamina D/metabolismo , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/etnologia , Deficiência de Vitamina D/urina , Adulto Jovem
20.
Eur J Vasc Endovasc Surg ; 52(5): 565-580, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27397116

RESUMO

OBJECTIVE: Identification of patients who will benefit from carotid endarterectomy is not entirely effective, primarily utilising degree of carotid stenosis. This study aimed at determining if microembolic signals (MES) detected by transcranial Doppler ultrasound (TCD) can provide clinically useful information regarding stroke risk in patients with carotid atherosclerosis. METHODS: A meta-analysis of prospective studies was performed. Three analyses were proposed investigating MES detection as a predictor of: stroke or TIA, stroke alone, and stroke or TIA but with an increased positivity threshold. Subgroup analysis was used to compare pre-operative (symptomatic or asymptomatic) patients and peri- or post-operative patients. RESULTS: Twenty-eight studies reported data regarding both MES status and neurological outcome. Of these, 22 papers reported data on stroke and TIA as an outcome, 19 on stroke alone, and eight on stroke and TIA with increased positivity threshold. At the median pre-test probability of 3.0%, the post-test probabilities of a stroke after a positive and negative TCD were 7.1% (95% CI 5-10.1) and 1.2% (95% CI 0.6-2.5), respectively. In addition, the sensitivities and specificities of each outcome showed that increasing the threshold for positivity to 10 MES per hour would make TCD a more clinically useful tool in peri- and post-operative patients. CONCLUSION: TCD provides clinically useful information about stroke risk for patients with carotid disease and is technically feasible in most patients. However, the generally weak level of evidence constituting this review means definitive recommendations cannot be made.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Embolia Intracraniana/diagnóstico por imagem , Ataque Isquêmico Transitório/etiologia , Acidente Vascular Cerebral/etiologia , Ultrassonografia Doppler Transcraniana , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Estenose das Carótidas/complicações , Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas , Feminino , Humanos , Embolia Intracraniana/etiologia , Embolia Intracraniana/fisiopatologia , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
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