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1.
Ophthalmic Physiol Opt ; 44(3): 483-490, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38372370

RESUMO

PURPOSE: Previous research has shown that accommodation deficits are common in individuals with Down syndrome (DS), but the origin and mechanisms behind these deficits are still unknown. The aim of this study was to investigate the characteristics of different ocular structures involved in accommodation, in particular the ciliary muscle (CM), in a population of individuals with DS to further understand this deficit and its mechanisms. METHODS: Thirty-two volunteer participants of pre-presbyopic age with (n = 16) and without DS (n = 16) were recruited. Temporal and nasal images of the CM were acquired using anterior segment optical coherence tomography (AS-OCT) while participants fixated an eccentrically located target. Analysis of CM parameters was undertaken using validated semi-automated software. Axial length, anterior chamber depth, lens thickness and corneal curvature were obtained with the Topcon Aladdin Optical Biometer and Corneal Topographer. Non-cycloplegic refractive error and accommodative ability were obtained with an open-field autorefractor and dynamic retinoscopy, respectively. Independent t-tests were conducted to determine differences in CM and other anterior segment parameters between participants with and without DS. RESULTS: No significant differences were found in the CM parameters studied between participants with and without DS (p > 0.05). In contrast, significant differences were found in visual acuity (p < 0.001), accommodative response (p < 0.001) and corneal curvature (K1 p = 0.003 and K2 p < 0.001) between participants with and without DS. CONCLUSIONS: Despite having poorer accommodation, pre-presbyopic adults with DS do not have a different CM morphology to that found in typically developing adults. These findings suggest that the accommodative deficit found in this population is not due to a mechanical deficit of the CM.


Assuntos
Síndrome de Down , Cristalino , Adulto , Humanos , Cristalino/anatomia & histologia , Corpo Ciliar/diagnóstico por imagem , Corpo Ciliar/anatomia & histologia , Corpo Ciliar/fisiologia , Acomodação Ocular , Tomografia de Coerência Óptica/métodos , Músculos
2.
Behav Res Methods ; 51(5): 2074-2084, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30875024

RESUMO

Infantile nystagmus (IN) describes a regular, repetitive movement of the eyes. A characteristic feature of each cycle of the IN eye movement waveform is a period in which the eyes are moving at minimal velocity. This so-called "foveation" period has long been considered the basis for the best vision in individuals with IN. In recent years, the technology for measuring eye movements has improved considerably, but there remains the challenge of calibrating the direction of gaze in tracking systems when the eyes are continuously moving. Identifying portions of the nystagmus waveform suitable for calibration typically involves time-consuming manual selection of the foveation periods from the eye trace. Without an accurate calibration, the exact parameters of the waveform cannot be determined. In this study, we present an automated method for segmenting IN waveforms with the purpose of determining the foveation positions to be used for calibration of an eye tracker. On average, the "point of regard" was found to be within 0.21° of that determined by hand-marking by an expert observer. This method enables rapid clinical quantification of waveforms and the possibility of gaze-contingent research paradigms being performed with this patient group.


Assuntos
Calibragem , Medições dos Movimentos Oculares , Automação , Movimentos Oculares , Humanos , Nistagmo Patológico , Acuidade Visual
3.
Optom Vis Sci ; 94(7): 760-769, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28609416

RESUMO

PURPOSE: This study presents a two-degree customized animated stimulus developed to evaluate smooth pursuit in children and investigates the effect of its predetermined characteristics (stimulus type and size) in an adult population. Then, the animated stimulus is used to evaluate the impact of different pursuit motion paradigms in children. METHODS: To study the effect of animating a stimulus, eye movement recordings were obtained from 20 young adults while the customized animated stimulus and a standard dot stimulus were presented moving horizontally at a constant velocity. To study the effect of using a larger stimulus size, eye movement recordings were obtained from 10 young adults while presenting a standard dot stimulus of different size (1° and 2°) moving horizontally at a constant velocity. Finally, eye movement recordings were obtained from 12 children while the 2° customized animated stimulus was presented after three different smooth pursuit motion paradigms. Performance parameters, including gains and number of saccades, were calculated for each stimulus condition. RESULTS: The animated stimulus produced in young adults significantly higher velocity gain (mean: 0.93; 95% CI: 0.90-0.96; P = .014), position gain (0.93; 0.85-1; P = .025), proportion of smooth pursuit (0.94; 0.91-0.96, P = .002), and fewer saccades (5.30; 3.64-6.96, P = .008) than a standard dot (velocity gain: 0.87; 0.82-0.92; position gain: 0.82; 0.72-0.92; proportion smooth pursuit: 0.87; 0.83-0.90; number of saccades: 7.75; 5.30-10.46). In contrast, changing the size of a standard dot stimulus from 1° to 2° did not have an effect on smooth pursuit in young adults (P > .05). Finally, smooth pursuit performance did not significantly differ in children for the different motion paradigms when using the animated stimulus (P > .05). CONCLUSIONS: Attention-grabbing and more dynamic stimuli, such as the developed animated stimulus, might potentially be useful for eye movement research. Finally, with such stimuli, children perform equally well irrespective of the motion paradigm used.


Assuntos
Movimentos Oculares/fisiologia , Percepção de Movimento/fisiologia , Acompanhamento Ocular Uniforme/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Generalização do Estímulo , Humanos , Masculino , Movimentos Sacádicos , Adulto Jovem
4.
Ophthalmic Physiol Opt ; 37(4): 531-541, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28656674

RESUMO

PURPOSE: Previous studies have reported that eye movements differ between good/average and poor readers. However, these studies have been limited to investigating eye movements during reading related tasks, and thus, the differences found could arise from deficits in higher cognitive processes involved in reading rather than oculomotor performance. The purpose of the study is to determine the extent to which eye movements in children with delayed reading skills are different to those obtained from children with good/average reading skills in non-reading related tasks. METHODS: After a screening optometric assessment, eye movement recordings were obtained from 120 children without delayed reading skills and 43 children with delayed reading skills (4 to 11 years) using a Tobii TX300 eye tracker. Cartoon characters were presented horizontally from -20° to +20° in steps of 5° to study saccades. An animated stimulus in the centre of the screen was presented for 8 seconds to study fixation stability. Saccadic main sequences, and the number and amplitude of the saccades during fixation were obtained for each participant. Children with delayed reading skills (n = 43) were unmasked after data collection was completed. Medians and quartiles were calculated for each eye movement parameter for children without (n = 120) and with (n = 43) delayed reading skills. RESULTS: Independent t-tests with Bonferroni correction showed no significant differences in any of the saccadic main sequence parameters (Slope, Intercept, A, n and Q ratio) between children without and with delayed reading (p > 0.01). Similarly, no significant differences were found in the number of saccades and their amplitude during the fixation task between the two groups (p > 0.05). Further, none of the gross optometric parameters assessed (visual acuity, refractive error, ocular alignment, convergence, stereopsis and accommodation accuracy) were found to be associated with delayed reading skills (p > 0.05). CONCLUSIONS: Eye movements in children with delayed reading skills are quantitatively similar to those found in children without delayed reading skills. These findings suggest that, in these children, delayed reading skills are not associated with eye movements and further question interventions targeted at improving eye movement control.


Assuntos
Acomodação Ocular , Percepção de Profundidade/fisiologia , Fixação Ocular/fisiologia , Leitura , Erros de Refração/fisiopatologia , Movimentos Sacádicos/fisiologia , Visão Binocular/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Acuidade Visual
5.
Clin J Sport Med ; 26(2): 133-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26192375

RESUMO

OBJECTIVE: To describe visual problems among athletes with intellectual disabilities (IDs) and the role of vision in special sports. DESIGN: A cross-sectional observational study. SETTING: Athletes participating in Special Olympics European Summer Games 2010 in Warsaw attended vision screening by Special Olympics Lions Clubs International Opening Eyes. PARTICIPANTS: Coaches were encouraged to bring all athletes to screening without selection; 900 athletes from 52 European countries participated. INTERVENTIONS: Standard noninvasive eye examination procedures. Independent variables were age, gender, sport, and country of origin. MAIN OUTCOME MEASURES: Eyeglasses wear, presenting visual acuity, refractive error, and ocular health. RESULTS: Testability rates were very high. Findings confirmed high prevalence of ocular/visual defects in people with ID. There was an association between acuity and sport discipline. Few athletes used sports glasses. Screening revealed a lack of eye care even in the most developed nations. CONCLUSIONS: The impact of vision on sports activity in athletes with ID is significant. More needs to be done to ensure good vision and safety correction for active people with ID. Better provision and greater awareness of eye care in people with ID is needed in all European societies. CLINICAL RELEVANCE: Data presented highlight the need for increased awareness of the role of vision in sporting achievements, personal development, and quality of life in active people with ID. Athletes with ID should have easily accessible comprehensive eye care, and when appropriate, corrective and protective glasses. This will require the efficient cooperation of vision specialists, coaches, carers, and athletes themselves.


Assuntos
Atletas/estatística & dados numéricos , Pessoas com Deficiência/estatística & dados numéricos , Transtornos da Visão/epidemiologia , Adolescente , Adulto , Criança , Estudos Transversais , Óculos/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Erros de Refração , Acuidade Visual , Adulto Jovem
6.
Philos Trans A Math Phys Eng Sci ; 373(2051)2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26303925

RESUMO

Nonlinear behaviour is ever-present in vibrations and other dynamical motions of engineering structures. Manifestations of nonlinearity include amplitude-dependent natural frequencies, buzz, squeak and rattle, self-excited oscillation and non-repeatability. This article primarily serves as an extended introduction to a theme issue in which such nonlinear phenomena are highlighted through diverse case studies. More ambitiously though, there is another goal. Both the engineering context and the mathematical techniques that can be used to identify, analyse, control or exploit these phenomena in practice are placed in the context of a mind-map, which has been created through expert elicitation. This map, which is available in software through the electronic supplementary material, attempts to provide a practitioner's guide to what hitherto might seem like a vast and complex research landscape.

7.
J Autism Dev Disord ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39133394

RESUMO

PURPOSE: There is a higher prevalence of visual problems in children with Autistic Spectrum Disorder (ASD) compared with the neuro-typical population. Issues relating to visual perception can be evident as atypical visual behaviours (ViBes). The aim of the study was to compare findings of parents and eye health professionals using questionnaires to describe visual function in young children with ASD. MATERIALS AND METHODS: Parents/Caregivers of patients diagnosed with ASD attending routine hospital eye clinics were invited to participate. A questionnaire to draw out presence of ViBes was completed by the parent prior to attending clinic. The clinician independently completed the same questionnaire and undertook a clinical ocular assessment. RESULTS: 32 children were recruited (mean age 7 years, range 4-11). Most caregivers indicated they had noted at least one atypical ViBe (97%, median 5, range 0-8). Parental-reported ViBe8 scores were higher than clinician-reported scores (p = 0.04). The most commonly reported ViBes by both groups related to use of vision at the same time as other senses, and atypical fixation (e.g. looking away during speech or side viewing). There was weak correlation between visual acuity and parental ViBe8 score (rho = 0.364) and no correlation between refractive error and parental ViBe8 score (rho = 0.047). CONCLUSION: Clinicians were likely to under-report atypical visual function compared with parent. Refraction and visual acuity alone do not detect all visual problems in children with ASD. A Visual Behaviour (ViBe) questionnaire offers a structured approach and shared language to allow documentation of functional visual assessment for both parents, carers, and educational professionals. Use of the ViBe questionnaire may promote understanding between caregiver and professional and provide a baseline for visual behaviours.

8.
Harmful Algae ; 133: 102600, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38485438

RESUMO

Dolichospermum is a cyanobacterial genus commonly associated with toxic blooms in lakes and brackish water bodies worldwide, and is a long-term resident of Lake Stechlin, northeastern Germany. In recent decades, shifts in the phosphorus loading and phytoplankton species composition have seen increased biomass of Dolichospermum during summer blooms from 1998, peaking around 2005, and declining after 2020. Cyanobacteria are known to rapidly adapt to new environments, facilitated by genome adaptation. To investigate the changes in genomic features that may have occurred in Lake Stechlin Dolichospermum during this time of increased phosphorus loading and higher biomass, whole genome sequence analysis was performed on samples of ten akinetes isolated from ten, 1 cm segments of a sediment core, representing a ∼45-year period from 1970 to 2017. Comparison of these genomes with genomes of extant isolates revealed a clade of Dolichospermum that clustered with the ADA-6 genus complex, with remarkable genome stability, without gene gain or loss events in response to recent environmental changes. The genome characteristics indicate that this species is suited to a deep-chlorophyll maximum, including additional light-harvesting and phosphorus scavenging genes. Population SNP analysis revealed two sub-populations that shifted in dominance as the lake transitioned between oligotrophic and eutrophic conditions. Overall, the results show little change within the population, despite diversity between extant populations from different geographic locations and the in-lake changes in phosphorus concentrations.


Assuntos
Cianobactérias , Lagos , Lagos/microbiologia , Cianobactérias/genética , Fitoplâncton , Biomassa , Fósforo
9.
Clin Radiol ; 68(6): 562-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23312672

RESUMO

AIM: To compare the success and complication associated with 4 and 5 F access systems prospectively in the treatment of infra-inguinal vascular disease. MATERIALS AND METHODS: One hundred and twenty consecutive patients were treated for lower limb vascular disease via a 4 F (n = 60) or 5 F (n = 60) access sheath over a 12 month period. All common femoral arteries were punctured in an antegrade direction with ultrasound guidance. Seven minutes of manual compression was applied and the groin assessed with ultrasound to document complications. Repeated manual compression was applied until haemostasis was achieved in all cases. Time to haemostasis, equipment used, patient biochemical data, and demographics were recorded. Patients were followed-up at a mean of 12 weeks post-procedure. RESULTS: Antegrade access and sheath insertion was achieved in all cases. The technical success of the procedure was 56/60 (93%) cases using 4 F access and 57 (95%) cases using 5 F access. The time to haemostasis was reduced to a mean of 8.2 min (range 7-12 min) with a 4 F system compared to a mean of 12 min (range 7-30 minutes) with a 5 F system (p = 0.045). Overall there were 12 complications (10%; 11 <2 cm haematomas and one pseudoaneurysm) noted on ultrasound post-haemostasis, although there was no statistically significance difference between the two groups. Hypertension and renal dysfunction were associated with complications (p < 0.05). A 4 F system used an additional average of 5.1 (range 3-8) wires and catheters compared to an additional average of 3.5 (range 2-6) wires and catheters when using a 5 F system (p = 0.002). A 4 F technique cost three-times that of a 5 F technique. CONCLUSION: Four and 5 F access sheaths allow safe and successful infra-inguinal angioplasty with a low complication rate. Hypertensive patients and those with impaired renal function are at increased risk of complications. There are increasing costs using a 4 F system offset by a decrease in time to haemostasis following manual compression but no reduction in complication rate.


Assuntos
Angioplastia/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Artéria Femoral/cirurgia , Hemostasia Cirúrgica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção
10.
Birth Defects Res ; 115(1): 67-78, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36398384

RESUMO

BACKGROUND: Few risk factors have been identified for nonsyndromic anotia/microtia (A/M). METHODS: We obtained data on cases and a reference population of all livebirths in Texas for 1999-2014 from the Texas Birth Defects Registry (TBDR) and Texas vital records. We estimated prevalence ratios (PRs) and 95% confidence intervals (CIs) for A/M (any, isolated, nonisolated, unilateral, and bilateral) using Poisson regression. We evaluated trends in prevalence rates using Joinpoint regression. RESULTS: We identified 1,322 cases, of whom 982 (74.3%) had isolated and 1,175 (88.9%) had unilateral A/M. Prevalence was increased among males (PR: 1.3, 95% CI: 1.2-1.4), offspring of women with less than high school education (PR: 1.3, 95% CI: 1.1-1.5), diabetes (PR: 2.0, 95% CI: 1.6-2.4), or age 30-39 versus 20-29 years (PR: 1.2, 95% CI: 1.0-1.3). The prevalence was decreased among offspring of non-Hispanic Black versus White women (PR: 0.6, 95% CI: 0.4-0.8) but increased among offspring of Hispanic women (PR: 2.9, 95% CI: 2.5-3.4) and non-Hispanic women of other races (PR: 1.7, 95% CI: 1.3-2.3). We observed similar results among cases with isolated and unilateral A/M. Sex disparities were not evident for nonisolated or bilateral phenotypes, nor did birth prevalence differ between offspring of non-Hispanic Black and non-Hispanic White women. Maternal diabetes was more strongly associated with nonisolated (PR: 4.5, 95% CI: 3.2-6.4) and bilateral A/M (PR: 5.0, 95% CI: 3.3-7.7). Crude prevalence rates increased throughout the study period (annual percent change: 1.82). CONCLUSION: We identified differences in the prevalence of nonsyndromic A/M by maternal race/ethnicity, education, and age, which may be indicators of unidentified social/environmental risk factors.


Assuntos
Microtia Congênita , Diabetes Gestacional , Feminino , Masculino , Humanos , Gravidez , Texas/epidemiologia , Etnicidade , Hispânico ou Latino
11.
Case Rep Ophthalmol ; 13(1): 286-291, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35702517

RESUMO

Voluntary flutter (sometimes known as "voluntary nystagmus") is a conjugate saccadic oscillation of the eyes that occurs in some healthy individuals. It has no relation to pathological nystagmus, which can manifest in infancy or become acquired later in life. This report presents an unusual case of voluntary flutter that presented in a 20-year-old male with autism spectrum disorder during ocular examination via direct ophthalmoscopy. Refraction and ocular motor balance were normal, and visual acuity was good in each eye (-0.10 logMAR). During direct ophthalmoscopy, a fine intermittent tremor was initiated. The patient was referred for further assessment, and eye movements were recorded at 1,000 Hz with an EyeLink 1000 eye tracker. Upon request, the patient could manifest voluntary flutter again and sustain the eye movements with effort during convergence. The voluntary flutter consisted of back-to-back saccadic oscillations in a predominantly horizontal direction, with an average frequency of 13 Hz and an amplitude of ∼8°, both reducing over time. We speculate that the discomfort induced by the proximity of the clinician during direct ophthalmoscopy examination may have triggered the eye oscillations. Although the oscillations typically manifest during convergence, atypical forms of voluntary flutter can also occur during divergence. Voluntary flutter can be a useful differential diagnosis in patients with a recently onset apparent "nystagmus," and no other neurological signs and symptoms.

12.
Invest Ophthalmol Vis Sci ; 63(2): 28, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35195683

RESUMO

Purpose: Children with Down's syndrome (DS) are known to have poorer visual acuity than neurotypical children. One report has shown that children with DS and nystagmus also have poor acuity when compared to typical children with nystagmus. What has not been established is the extent of any acuity deficit due to nystagmus and whether nystagmus affects refractive error within a population with DS. Methods: Clinical records from the Cardiff University Down's Syndrome Vision Research Unit were examined retrospectively. Binocular visual acuity and refraction data were available for 50 children who had DS and nystagmus and 176 children who had DS but no nystagmus. Data were compared between the two groups and with published data for neurotypical children with nystagmus. Results: The study confirms the deficit in acuity in DS, compared to neurotypical children, of approximately 0.2 logMAR and shows a deficit attributable to nystagmus of a further 0.2 logMAR beyond the first year of life. Children with both DS and nystagmus clearly have a significant additional impairment. Children with DS have a wide range of refractive errors, but nystagmus increases the likelihood of myopia. Prevalence and axis direction of astigmatism, on the other hand, appear unaffected by nystagmus. Conclusions: Nystagmus confers an additional visual impairment on children with DS and must be recognized as such by families and educators. Children with both DS and nystagmus clearly need targeted support.


Assuntos
Síndrome de Down/fisiopatologia , Nistagmo Patológico/fisiopatologia , Erros de Refração/fisiopatologia , Transtornos da Visão/fisiopatologia , Acuidade Visual/fisiologia , Astigmatismo/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Nistagmo Patológico/diagnóstico , Refração Ocular/fisiologia , Estudos Retrospectivos , Testes Visuais , Visão Binocular/fisiologia
13.
BMJ Mil Health ; 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35878969

RESUMO

Military medicine has been evolving for over 5000 years of recorded civilisation and conflict. The Army Medical Services performed poorly during the Crimean War and the British Army introduced a professional training course for medical officers in 1860. The Army Medical School and the predecessor of today's Post-Graduate Medical and Nursing Officers (PGMNO) course have had to adapt to changes in British foreign policy and military requirements. The Army Medical School instigated a rigorous scientific medical training which led to major advances in the study of tropical diseases and trauma medicine. These advances were quickly included in the training of future cohorts. Although the Army Medical School has now closed, the PGMNO course thrives at its new location at the Defence Medical Academy, Whittington. Modern general duties medical officers (GDMOs) must be able to provide medical care in a range of austere environments, including humanitarian relief and conflict zones. New clinicians complete their basic military training before completing the PGMNO course and the Diploma in the Medical Care of Catastrophes. This programme ensures that GDMOs and military nurse practitioners gain a wide knowledge of the latest military and humanitarian medicine. The current era will require clinicians who are competent generalists, who can perform in small teams in dispersed locations. This article summarises the development of the British Army's PGMNO course and the evolution of its syllabus as part of the Humanitarian and Disaster Relief Operations special issue of BMJ Military Health.

14.
Front Hum Neurosci ; 15: 673342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194306

RESUMO

It is widely recognised that children with Down syndrome have a broad range and a high prevalence of visual deficits and it has been suggested that those with Down syndrome are more likely to exhibit visual perception deficits indicative of cerebral visual impairment. This exploratory study aims to determine the prevalence of behavioural features suggestive of cerebral visual impairment (CVI) occurring with Down syndrome and whether the visual problems can be ascribed to optometric factors. A cohort of 226 families of children with Down syndrome (trisomy 21), aged 4-17, were invited to participate in a validated question inventory, to recognise visual perception issues. The clinical records of the participants were then reviewed retrospectively. A five-question screening instrument was used to indicate suspected CVI. The majority of the 81 families who responded to the questionnaire reported some level of visual perceptual difficulty in their child. Among this cohort, the prevalence of suspected CVI as indicated by the screening questionnaire was 38%. Only ametropia was found to have a significant association with suspected CVI, although this increased the correct prediction of suspected CVI outcome by only a small amount. Results suggest that children with Down syndrome are more likely to experience problems consistent with cerebral visual impairment, and that these may originate from a similar brain dysfunction to that which contributes to high levels of ametropia and failure to emmetropise. It is important that behavioural features of CVI are recognised in children with Down syndrome, further investigations initiated and appropriate management applied.

15.
Sci Rep ; 11(1): 19613, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34608220

RESUMO

Metabolomics may shed light on treatment response in childhood acute lymphoblastic leukemia (ALL), however, most assessments have analyzed bone marrow or cerebrospinal fluid (CSF), which are not collected during all phases of therapy. Blood is collected frequently and with fewer risks, but it is unclear whether findings from marrow or CSF biomarker studies may translate. We profiled end-induction plasma, marrow, and CSF from N = 10 children with B-ALL using liquid chromatography-mass spectrometry. We estimated correlations between plasma and marrow/CSF metabolite abundances detected in ≥ 3 patients using Spearman rank correlation coefficients (rs). Most marrow metabolites were detected in plasma (N = 661; 81%), and we observed moderate-to-strong correlations (median rs 0.62, interquartile range [IQR] 0.29-0.83). We detected 328 CSF metabolites in plasma (90%); plasma-CSF correlations were weaker (median rs 0.37, IQR 0.07-0.70). We observed plasma-marrow correlations for metabolites in pathways associated with end-induction residual disease (pyruvate, asparagine) and plasma-CSF correlations for a biomarker of fatigue (gamma-glutamylglutamine). There is considerable overlap between the plasma, marrow, and CSF metabolomes, and we observed strong correlations for biomarkers of clinically relevant phenotypes. Plasma may be suitable for biomarker studies in B-ALL.


Assuntos
Biomarcadores , Medula Óssea/metabolismo , Metaboloma , Metabolômica , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Adolescente , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Medula Óssea/patologia , Criança , Pré-Escolar , Biologia Computacional/métodos , Feminino , Humanos , Lactente , Masculino , Metabolômica/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/etiologia , Prognóstico
16.
Birth Defects Res ; 113(1): 43-54, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33091229

RESUMO

BACKGROUND: We sought to investigate associations between maternal/infant characteristics and isolated craniosynostosis as well as its subtypes sagittal, metopic, and coronal synostosis, and assess trends in the prevalence of these conditions. METHODS: We identified cases in the Texas Birth Defects Registry from 1999 to 2014. We used Poisson regression to identify associations between maternal/infant characteristics and craniosynostosis. We used joinpoint regression and unadjusted Poisson regression to evaluate temporal trends. Finally, we computed adjusted Poisson models to evaluate whether temporal trends were evident after accounting for changes in the population distributions of maternal/infant characteristics over time. RESULTS: Relative to all live births in the general population, cases were more frequently male or preterm. Mothers of cases were more frequently non-Hispanic white and more frequently obese. Non-Hispanic black or Hispanic maternal race/ethnicity was associated with a lower prevalence of all craniosynostosis subtypes. Previous live births were associated with sagittal synostosis; residence on the U.S.-Mexico border was associated with sagittal and coronal synostosis. The prevalence of any isolated craniosynostosis increased (average annual percent change estimated from joinpoint regression [AAPC]: 2.9%), as did the prevalences of sagittal (AAPC: 3.3%) and metopic synostosis (AAPC: 5.4%). In crude Poisson models, the same temporal trends were observed, however these were attenuated after adjusting for maternal/infant characteristics. CONCLUSIONS: Prevalence of isolated craniosynostosis increased from 1999 to 2014. The largest AAPC was observed for metopic synostosis. Changes in the population distribution of associated maternal/infant characteristics may explain these trends.


Assuntos
Craniossinostoses , Craniossinostoses/epidemiologia , Etnicidade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mães , Prevalência , Fatores de Risco
17.
Osteoporos Int ; 21(9): 1529-36, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20091404

RESUMO

SUMMARY: A 1-year randomized controlled trial of resistance training compared with a control group was undertaken in 143 men aged 55-80 years. Although hip bone mineral density, lean body mass, and function increased in both groups, lean body mass and function but not bone density increased more in the resistance group. INTRODUCTION: Previous studies have demonstrated a positive effect of resistance training on bone mineral density (BMD) in postmenopausal women, but the effect in men is unclear. The aim was to examine the effect of a 1-year resistance training program on bone and lean body mass in 143 men aged 55-80 years, randomized to either resistance training or active control. METHODS: Resistance exercises were selected to provide loading at the hips. Measurements were taken at 0, 6, and 12 months for BMD (whole body, hip, and spine), lean body mass, strength, and functional fitness. RESULTS: The intervention showed a significant increase in total hip BMD for both groups at 12 months (active control, 1,014-1,050 mg/cm(2); resistance, 1,045-1,054 mg/cm(2), p < 0.05) with no increased effect of resistance training compared to active control. However, compared to the active control group, the resistance group increased their lean body mass (active control, 0.1 +/- 2.1%; resistance, 1.5 +/- 2.7%, p < 0.05), fitness (active control, 4.6 +/- 11.1%; resistance, 13.0 +/- 13.4%, p < 0.05), and lower limb muscle strength (active control, 14.3 +/- 16.8%; resistance, 39.4 +/- 30.87%, p < 0.05). CONCLUSIONS: In contrast to previous findings in older women, in older men, a resistance training program does not increase hip bone mass more than walking 30 min three times a week.


Assuntos
Extremidade Inferior/fisiologia , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Composição Corporal/fisiologia , Índice de Massa Corporal , Densidade Óssea/fisiologia , Seguimentos , Articulação do Quadril/fisiologia , Humanos , Vértebras Lombares/fisiologia , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia
18.
Ophthalmic Physiol Opt ; 30(6): 740-7, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21205259

RESUMO

The literature concerning subjects who have reading difficulties has repeatedly noted their abnormal eye movements. The Developmental Eye Movement (DEM) test was developed on the assumption that poor eye movement control is a major cause of reading difficulties. The hypothesis tested by this study was that practice in fluent reading trains the eye movements that result in a good DEM score, whilst poor readers will exhibit low DEM scores due to insufficient training. English readers (43 children, 20 adults), and Arabic readers (six children, five adults) were recruited. The DEM test was administered twice, performed once reading the horizontal section in the habitual reading direction and secondly in the opposite direction, thus enabling the subjects' eye movements to be compared when reading in their habitual direction and when reading in a direction which is relatively unpracticed. Paired t-tests showed that the difference in eye movements (quantified via the DEM test ratio) between the two opposing reading directions was significant in English reading adults, English reading children and Arabic reading children, but not significant in the Arabic adults, who were equally practised in reading in the two directions. The results support the hypothesis that abnormal eye movements are more likely to be an effect and not the cause of reading difficulties. The DEM test should not be used to diagnose eye movement difficulties in a patient with poor reading ability.


Assuntos
Movimentos Oculares/fisiologia , Leitura , Adulto , Envelhecimento/fisiologia , Criança , Desenvolvimento Infantil/fisiologia , Medições dos Movimentos Oculares , Humanos , Idioma , Transtornos da Motilidade Ocular/diagnóstico , Transtornos da Motilidade Ocular/fisiopatologia , Adulto Jovem
19.
BMJ Mil Health ; 166(E): e70-e72, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31129647

RESUMO

British Armed Forces are facing the most significant recruitment crisis since 2010. An important contributing factor to the recruitment crisis is the rise in obesity of the UK population. At Army Training Centre Pirbright, a weight management programme (WMP) has been established for recruits who have failed their initial medical assessment (IMA). To determine the proportion of recruits who entered the WMP and passed basic and initial trade training, allowing entry into the British Army. Retrospective service evaluation of recruits entering WMP from inception in April 2015 to August 2018. Medical records were used to assess whether recruits completed initial training. 72.3% of recruits included in the WMP who would have previously failed their IMA because of a high body mass index (BMI) passed basic and initial trade training. This evaluation demonstrates potential for candidates otherwise excluded based on BMI. This WMP delivers structured nutritional support and encourages physical training. Once a BMI enters the accepted range, recruits could enter basic training. This WMP would deliver structured nutritional support and encourage physical training, with the aim of promoting healthy lifestyles. Neither the Royal Navy nor the Royal Air Force currently have a WMP. There is potential for WMPs to be introduced to all three services. UK Armed Forces face a recruitment crisis and need to be adaptable with a population where obesity is prevalent. At Pirbright 72.3% of candidates in the WMP passed basic and initial trade training.


Assuntos
Militares/psicologia , Seleção de Pessoal/métodos , Programas de Redução de Peso/métodos , Adolescente , Índice de Massa Corporal , Feminino , Humanos , Masculino , Militares/educação , Militares/estatística & dados numéricos , Obesidade/psicologia , Obesidade/terapia , Seleção de Pessoal/estatística & dados numéricos , Estudos Retrospectivos , Reino Unido , Programas de Redução de Peso/estatística & dados numéricos , Adulto Jovem
20.
Sci Rep ; 10(1): 10031, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32572106

RESUMO

Down syndrome (DS) is frequently associated with cataract, but there remains scant information about DS cataract morphology. Supra-nuclear cataracts in DS have been proposed as indicative of beta-amyloid (Aß) aggregation and thus potential biomarkers for Alzheimer's (AD). This study employed anterior segment OCT (AS-OCT) and slit-lamp (SL) photography to image the crystalline lens in DS, compared with adult controls. Lens images were obtained post-dilation. Using MATLAB, AS-OCT images were analysed and lens opacities calculated as pixel intensity and area ratios. SL images were classified using LOCS III. Subjects were n = 28 DS (mean ± SD 24.1 ± 14.3years), and n = 36 controls (54.0 ± 3.4years). For the DS group, AS-OCT imaging revealed the frequent presence of small dot opacities (27 eyes, 50%) in the cortex and nucleus of the lens, covering an area ranging from 0.2-14%. There was no relation with age or visual acuity and these dot opacities (p > 0.5) and they were not present in any control lenses. However, their location and morphology does not coincide with previous reports linking these opacities with Aß accumulation and AD. Four participants (14%) in the DS group had clinically significant age-related cataracts, but there was no evidence of early onset of age-related cataracts in DS.


Assuntos
Câmara Anterior/diagnóstico por imagem , Catarata/etiologia , Síndrome de Down/complicações , Adolescente , Adulto , Câmara Anterior/patologia , Estudos de Casos e Controles , Catarata/diagnóstico por imagem , Catarata/patologia , Criança , Síndrome de Down/patologia , Feminino , Humanos , Cristalino/diagnóstico por imagem , Cristalino/patologia , Masculino , Pessoa de Meia-Idade , Microscopia com Lâmpada de Fenda , Tomografia de Coerência Óptica , Adulto Jovem
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