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1.
Psychol Med ; 53(12): 5428-5441, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-35879886

RESUMEN

BACKGROUND: The impact of the coronavirus disease 2019 (COVID-19) pandemic on mental health is still being unravelled. It is important to identify which individuals are at greatest risk of worsening symptoms. This study aimed to examine changes in depression, anxiety and post-traumatic stress disorder (PTSD) symptoms using prospective and retrospective symptom change assessments, and to find and examine the effect of key risk factors. METHOD: Online questionnaires were administered to 34 465 individuals (aged 16 years or above) in April/May 2020 in the UK, recruited from existing cohorts or via social media. Around one-third (n = 12 718) of included participants had prior diagnoses of depression or anxiety and had completed pre-pandemic mental health assessments (between September 2018 and February 2020), allowing prospective investigation of symptom change. RESULTS: Prospective symptom analyses showed small decreases in depression (PHQ-9: -0.43 points) and anxiety [generalised anxiety disorder scale - 7 items (GAD)-7: -0.33 points] and increases in PTSD (PCL-6: 0.22 points). Conversely, retrospective symptom analyses demonstrated significant large increases (PHQ-9: 2.40; GAD-7 = 1.97), with 55% reported worsening mental health since the beginning of the pandemic on a global change rating. Across both prospective and retrospective measures of symptom change, worsening depression, anxiety and PTSD symptoms were associated with prior mental health diagnoses, female gender, young age and unemployed/student status. CONCLUSIONS: We highlight the effect of prior mental health diagnoses on worsening mental health during the pandemic and confirm previously reported sociodemographic risk factors. Discrepancies between prospective and retrospective measures of changes in mental health may be related to recall bias-related underestimation of prior symptom severity.


Asunto(s)
COVID-19 , Trastornos por Estrés Postraumático , Femenino , Humanos , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/psicología , COVID-19/epidemiología , Pandemias , Depresión/psicología , Estudios Retrospectivos , Estudios Prospectivos , SARS-CoV-2 , Ansiedad/psicología , Reino Unido/epidemiología
2.
Health Qual Life Outcomes ; 20(1): 18, 2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35115013

RESUMEN

OBJECTIVES: This study develops an adolescent value set for a child-centred dental caries-specific measure of oral health-related quality of life (OHRQoL) based upon CARIES-QC (Caries Impacts and Experiences Questionnaire for Children). This study develops a new approach to valuing child health by eliciting adolescent preferences and anchoring these onto the 1-0 full health-dead QALY (quality adjusted life year) scale using ordinal adult preferences. METHODS: Two online surveys were created to elicit preferences for the CARIES-QC classification system. The first comprised best-worst scaling (BWS) tasks for completion by adolescents aged 11-16 years. The second comprised discrete choice experiment tasks with a duration attribute (DCETTO) for completion by adults aged over 18 years. Preferences were modelled using the conditional logit model. Mapping regressions anchored the adolescent BWS data onto the QALY scale using adult DCETTO values, since the BWS survey data alone cannot generate anchored values. RESULTS: 723 adolescents completed the BWS survey and 626 adults completed the DCETTO survey. The samples were representative of UK adolescent and adult populations. Fully consistent and robust models were produced for both BWS and DCETTO data. BWS preferences were mapped onto DCETTO values, resulting utility estimates for each health state defined by the classification system. CONCLUSION: This is the first measure with predetermined scoring based on preferences to be developed specifically for use in child oral health research, and uses a novel technique to generate a value set using adolescent preferences. The estimates can be used to generate QALYs in economic evaluations of interventions to improve children's oral health.


Asunto(s)
Caries Dental , Calidad de Vida , Adolescente , Adulto , Caries Dental/terapia , Susceptibilidad a Caries Dentarias , Estado de Salud , Humanos , Persona de Mediana Edad , Años de Vida Ajustados por Calidad de Vida , Encuestas y Cuestionarios
3.
Anaesthesia ; 75(9): 1180-1190, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32072617

RESUMEN

Whether third-generation hydroxyethyl starch solutions provoke kidney injury or haemostatic abnormalities in patients having cardiac surgery remains unclear. We tested the hypotheses that intra-operative administration of a third-generation starch does not worsen postoperative kidney function or haemostasis in cardiac surgical patients compared with human albumin 5%. This triple-blind, non-inferiority, clinical trial randomly allocated patients aged 40-85 who underwent elective aortic valve replacement, with or without coronary artery bypass grafting, to plasma volume replacement with 6% starch 130/0.4 vs. 5% human albumin. Our primary outcome was postoperative urinary neutrophil gelatinase-associated lipocalin concentrations, a sensitive and early marker of postoperative kidney injury. Secondarily, we evaluated urinary interleukin-18; acute kidney injury using creatinine RIFLE criteria, coagulation measures, platelet count and function. Non-inferiority (delta 15%) was assessed with correction for multiple comparisons. We enrolled 141 patients (69 starch, 72 albumin) as planned. Results of the primary analysis demonstrated that postoperative urine neutrophil gelatinase-associated lipocalin (median (IQR [range])) was slightly lower with hydroxyethyl starch (5 (1-68 [0-996]) ng.ml-1 ) vs. albumin (5 (2-74 [0-1604]) ng.ml-1 ), although not non-inferior [ratio of geometric means (95%CI) 0.91 (0.57, 1.44); p = 0.15] due to higher than expected variability. Urine interleukin-18 concentrations were reduced, but interleukin-18 and kidney injury were again not non-inferior. Of 11 individual coagulation measures, platelet count and function, nine were non-inferior to albumin. Two remaining measures, thromboelastographic R value and arachidonic acid-induced platelet aggregation, were clinically similar but with wide confidence intervals. Starch administration during cardiac surgery produced similar observed effects on postoperative kidney function, coagulation, platelet count and platelet function compared with albumin, though greater than expected variability and wide confidence intervals precluded the conclusion of non-inferiority. Long-term mortality and kidney function appeared similar between starch and albumin.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Procedimientos Quirúrgicos Cardíacos , Derivados de Hidroxietil Almidón/farmacología , Cuidados Intraoperatorios/métodos , Riñón/efectos de los fármacos , Sustitutos del Plasma/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Hemostáticos , Humanos , Riñón/fisiología , Masculino , Persona de Mediana Edad
4.
Community Dent Health ; 37(2): 143-149, 2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32212436

RESUMEN

INTRODUCTION: Silver diamine fluoride (SDF) is used to prevent and arrest caries across the globe, particularly in the developing world. Whilst its use in the Western World is increasing, it is not yet routinely used in the United Kingdom, nor is it advocated by our national guidelines. OBJECTIVES: To explore the literature surrounding the use of SDF, and consider the reasons why SDF has not yet been widely adopted in the United Kingdom (UK). DISCUSSION: There is a growing evidence base for the use of SDF for the arrest and prevention of dental caries in the primary and permanent dentition. Potential side effects include staining of carious tooth structure, but in some cases this is acceptable to parents. There is no evidence for the cost effectiveness of SDF, although it may be a reasonably cost-effective option. CONCLUSION: SDF is perhaps not yet widely adopted in the UK due to a perceived parental concern about its staining effect. With a growing evidence base and reportedly higher efficacy than fluoride varnish for caries prevention and arrest, SDF has the potential to play an important role in managing dental disease in children and young people in both primary and secondary care.


Asunto(s)
Caries Dental , Adolescente , Cariostáticos , Niño , Fluoruros Tópicos , Humanos , Compuestos de Amonio Cuaternario , Compuestos de Plata , Diente Primario , Reino Unido
5.
Proc Biol Sci ; 286(1894): 20182007, 2019 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30963874

RESUMEN

Frugivores play differing roles in shaping dispersal patterns yet seed dispersal distance is rarely quantified across entire communities. We model seed dispersal distance using gut passage times and bird movement for the majority (39 interactions) of known bird-tree interactions on the island of Saipan to highlight differences in seed dispersal distances provided by the five avian frugivores. One bird species was found to be a seed predator rather than a disperser. The remaining four avian species dispersed seeds but differences in seed dispersal distance were largely driven by interspecific variation in bird movement rather than intraspecific variation in gut passage times. The median dispersal distance was at least 56 m for all species-specific combinations, indicating all species play a role in reducing high seed mortality under the parent tree. However, one species-the Micronesian Starling-performed 94% of dispersal events greater than 500 m, suggesting this species could be a key driver of long-distance dispersal services (e.g. linking populations, colonizing new areas). Assessing variation in dispersal patterns across this network highlights key sources of variation in seed dispersal distances and suggests which empirical approaches are sufficient for modelling how seed dispersal mutualisms affect populations and communities.


Asunto(s)
Columbidae/fisiología , Conducta Alimentaria , Magnoliopsida/fisiología , Dispersión de Semillas , Pájaros Cantores/fisiología , Simbiosis , Distribución Animal , Animales , Micronesia , Especificidad de la Especie
6.
Diabet Med ; 36(2): 203-213, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30098217

RESUMEN

AIM: To inform targeted interventions for women with gestational diabetes mellitus (GDM) by exploring the factors that influence their health behaviours and their preferences for lifestyle support. METHODS: Participants were women with previous GDM taken from a diverse inner-city UK population. Data collection involved focus groups (n = 35 women in six groups) and semi-structured interviews (n = 15 women). The transcribed data were analysed using framework analysis. RESULTS: Eight themes relating to factors influencing health behaviour were identified: psychological legacy of pregnancy, relationships with healthcare professionals, physical impacts of pregnancy, social support and cultural norms, life-scheduling, understanding and risk perception, appetite regulation, and prioritization of the baby. The women's recommendations for intervention components included addressing the emotional stress of pregnancy; conveying personalized risk in a motivational way, adopting a family-centered approach, focusing on women's health rather than just the infant's, and developing flexible interventions. These recommendations were used to construct a model integrating the behaviour-regulating factors with a suggested framework for intervention. CONCLUSIONS: This study identified some common drivers that may regulate the health behaviours of women following GDM, and recognized some ways to improve care to impact on this. Interventions for diabetes prevention in this population need to address factors at both the individual and systemic levels.


Asunto(s)
Diabetes Gestacional/psicología , Conductas Relacionadas con la Salud , Adulto , Estudios de Cohortes , Cultura , Diabetes Gestacional/dietoterapia , Diabetes Gestacional/prevención & control , Dieta Saludable/psicología , Ejercicio Físico/fisiología , Ejercicio Físico/psicología , Femenino , Conocimientos, Actitudes y Práctica en Salud , Estilo de Vida Saludable , Humanos , Persona de Mediana Edad , Motivación , Paridad , Embarazo , Relaciones Profesional-Paciente , Recurrencia , Apoyo Social , Adulto Joven
7.
BMC Oral Health ; 19(1): 132, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31262293

RESUMEN

BACKGROUND: Economic evaluations provide policy makers with information to facilitate efficient resource allocation. To date, the quality and scope of economic evaluations in the field of child oral health has not been evaluated. Furthermore, whilst the involvement of children in research has been actively encouraged in recent years, the success of this movement in dental health economics has not yet been explored. This review aimed to determine the quality and scope of published economic evaluations applied to children's oral health and to consider the extent of children's involvement. METHODS: The following databases were searched: CINAHL, Cochrane Library, Econlit, EThOS, MEDLINE, NHS EED, OpenGrey, Scopus, Web of Science. Full economic evaluations, relating to any aspect of child oral health, published after 1997 were included and appraised against the Drummond checklist and the Consolidated Health Economic Evaluation Reporting Standards by a team of four calibrated reviewers. Data were also extracted regarding children's involvement and the outcome measures used. RESULTS: Two thousand seven hundred fifteen studies were identified, of which 46 met the inclusion criteria. The majority (n = 38, 82%) were cost-effectiveness studies, with most focusing on the prevention or management of dental caries (n = 42, 91%). One study quantified outcomes in Quality Adjusted Life Years (QALYs), and one study utilised a child-reported outcome measure. The mean percentage of applicable Drummond checklist criteria met by the studies in this review was 48% (median = 50%, range = 0-100%) with key methodological weaknesses noted in relation to discounting of costs and outcomes. The mean percentage of applicable CHEERS criteria met by each study was 77% (median = 83%, range = 33-100%), with limited reporting of conflicts of interest. Children's engagement was largely overlooked. CONCLUSIONS: There is a paucity of high-quality economic evaluations in the field of child oral health. This deficiency could be addressed through the endorsement of standardised economic evaluation guidelines by dental journals. The development of a child-centred utility measure for use in paediatric oral health would enable researchers to quantify outcomes in terms of quality adjusted life years (QALYs) whilst promoting child-centred research.


Asunto(s)
Salud Bucal/economía , Niño , Análisis Costo-Beneficio , Caries Dental , Humanos , Evaluación de Resultado en la Atención de Salud , Años de Vida Ajustados por Calidad de Vida
8.
Epidemiol Infect ; 145(11): 2254-2262, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28689510

RESUMEN

Information on the factors that cause or amplify foodborne illness outbreaks (contributing factors), such as ill workers or cross-contamination of food by workers, is critical to outbreak prevention. However, only about half of foodborne illness outbreaks reported to the United States' Centers for Disease Control and Prevention (CDC) have an identified contributing factor, and data on outbreak characteristics that promote contributing factor identification are limited. To address these gaps, we analyzed data from 297 single-setting outbreaks reported to CDC's new outbreak surveillance system, which collects data from the environmental health component of outbreak investigations (often called environmental assessments), to identify outbreak characteristics associated with contributing factor identification. These analyses showed that outbreak contributing factors were more often identified when an outbreak etiologic agent had been identified, when the outbreak establishment prepared all meals on location and served more than 150 meals a day, when investigators contacted the establishment to schedule the environmental assessment within a day of the establishment being linked with an outbreak, and when multiple establishment visits were made to complete the environmental assessment. These findings suggest that contributing factor identification is influenced by multiple outbreak characteristics, and that timely and comprehensive environmental assessments are important to contributing factor identification. They also highlight the need for strong environmental health and food safety programs that have the capacity to complete such environmental assessments during outbreak investigations.


Asunto(s)
Brotes de Enfermedades , Contaminación de Alimentos , Enfermedades Transmitidas por los Alimentos/epidemiología , Vigilancia de la Población , Centers for Disease Control and Prevention, U.S. , Enfermedades Transmitidas por los Alimentos/microbiología , Humanos , Estados Unidos/epidemiología
9.
Diabet Med ; 32(11): 1453-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26213236

RESUMEN

AIM: To evaluate the sustainability of the benefits of continuous subcutaneous insulin infusion therapy in routine practice in a cohort of adults with diabetes. METHODS: The clinical records of all adults starting continuous subcutaneous insulin infusion over 12 years at our centre were included in this study. Baseline and mean annual HbA(1c) levels were recorded. The frequency of mild-to-moderate and severe hypoglycaemia and hypoglycaemia awareness were analysed in a subgroup. RESULTS: Adequate data were available from 327 patients, of whom 71% were female. The patients' mean ± sd age was 41 ± 14 years, the mean ± sd (range) follow-up for continuous subcutaneous insulin infusion was 4.3 ± 2.7 (1-12) years. The mean ± sd HbA(1c) concentration fell by 8 ± 5 mmol/mol (0.7 ± 0.5%) at year 1 [to 63 ± 12 mmol/mol from 70 ± 18 mmol/mol (7.9 ± 1.1% from 8.6 ± 1.6%); P < 0.0005], sustained to year 5. In patients with initial poor control, HbA(1c) dropped by 12 ± 11 mmol/mol (1.1 ± 1.0%; P < 0.0005) at year 1, sustained to year 6. The percentage of patients with ≥ 5 mild to moderate hypoglycaemic episodes per week fell from 29 to 12% (n = 163; P = 0.006). In the subgroup (n = 87; follow-up 2.5 ± mean ± sd 1.1 years), the frequency of severe hypoglycaemia fell from 0.6 ± 1.7 episodes per patient per year to 0.3 ± 0.9 (P = 0.047). Of 24 patients with impaired awareness of hypoglycaemia (Gold score ≥ 4), the mean ± sd Gold score improved from 4.9 ± 0.9 to 3.8 ± 1.7 (P = 0.011). Nine people regained awareness. No deterioration in HbA(1c) was seen in the hypoglycaemia-prone groups. CONCLUSIONS: The benefits of continuous subcutaneous insulin infusion with regard to improving glycaemic control and reducing hypoglycaemia frequency, along with improvement in hypoglycaemia awareness without deterioration in glycaemic control, can be sustained over several years in clinical practice.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hiperglucemia/prevención & control , Hipoglucemia/prevención & control , Hipoglucemiantes/administración & dosificación , Sistemas de Infusión de Insulina , Insulina/administración & dosificación , Adulto , Estudios de Cohortes , Terapia Combinada , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/dietoterapia , Dieta para Diabéticos , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Conocimientos, Actitudes y Práctica en Salud , Hospitales Universitarios , Humanos , Hiperglucemia/fisiopatología , Hipoglucemia/fisiopatología , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Londres , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
10.
Diabetes Metab Res Rev ; 30(3): 175-90, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24185859

RESUMEN

Hypoglycaemia remains an over-riding factor limiting optimal glycaemic control in type 1 diabetes. Severe hypoglycaemia is prevalent in almost half of those with long-duration diabetes and is one of the most feared diabetes-related complications. In this review, we present an overview of the increasing body of literature seeking to elucidate the underlying pathophysiology of severe hypoglycaemia and the limited evidence behind the strategies employed to prevent episodes. Drivers of severe hypoglycaemia including impaired counter-regulation, hypoglycaemia-associated autonomic failure, psychosocial and behavioural factors and neuroimaging correlates are discussed. Treatment strategies encompassing structured education, insulin analogue regimens, continuous subcutaneous insulin infusion pumps, continuous glucose sensing and beta-cell replacement therapies have been employed, yet there is little randomized controlled trial evidence demonstrating effectiveness of new technologies in reducing severe hypoglycaemia. Optimally designed interventional trials evaluating these existing technologies and using modern methods of teaching patients flexible insulin use within structured education programmes with the specific goal of preventing severe hypoglycaemia are required. Individuals at high risk need to be monitored with meticulous collection of data on awareness, as well as frequency and severity of all hypoglycaemic episodes.


Asunto(s)
Diabetes Mellitus Tipo 1/metabolismo , Hipoglucemia/metabolismo , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/psicología , Humanos , Hipoglucemia/prevención & control , Hipoglucemia/psicología , Hipoglucemiantes/efectos adversos , Insulina/efectos adversos
11.
Neuropsychol Rehabil ; 24(3-4): 554-71, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24533782

RESUMEN

A regression modelling approach for the analysis of single case designs (SCDs) is described in this paper. The approach presented addresses two key issues in the analysis of SCDs. The first issue is that of serial dependence among the observations in SCDs. The second issue is that of an effect size measure appropriate for SCDs. As with traditional between-subjects experimental designs, effect size measures are critical in assessing the impact of interventions in SCDs. Although effect size measures when there is level change without trend are straightforward to obtain and have been well studied, the situation is different when there are changes in both level and trend. An effect size measure that combines changes in levels and slopes and that is comparable to the d-type effect size measure obtained in between-subjects designs is presented. Finally, an inferential procedure for assessing the effect of the intervention based on the effect size measure is provided and illustrated.


Asunto(s)
Análisis de Regresión , Proyectos de Investigación/estadística & datos numéricos , Humanos
12.
JDR Clin Trans Res ; 9(2): 190-192, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37554046

RESUMEN

KNOWLEDGE TRANSFER STATEMENT: Oral health research and program evaluation should consider alternative outcome measures for population oral health other than the DMFT index.


Asunto(s)
Caries Dental , Salud Bucal , Humanos , Caries Dental/epidemiología , Evaluación de Resultado en la Atención de Salud , Políticas
13.
Br J Cancer ; 108(10): 2130-41, 2013 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-23591193

RESUMEN

BACKGROUND: Central nervous system primitive neuroectodermal tumours (CNS PNETs) are embryonal tumours occurring predominantly in children. Current lack of knowledge regarding their underlying biology hinders development of more effective treatments. We previously identified WNT/ß-catenin pathway activation in one-third of CNS PNETs, which was potentially linked to a better prognosis. In this study, we have extended our cohort, achieving a statistically significant correlation with prognosis. We additionally investigated the biological effects of WNT/ß-catenin pathway activation in tumour pathogenesis. METHODS: A total of 42 primary and 8 recurrent CNS PNETs were analysed for WNT/ß-catenin pathway status using ß-catenin immunohistochemistry. Genomic copy number and mRNA expression data were analysed to identify a molecular profile linked to WNT/ß-catenin pathway activation. RESULTS: Pathway activation was seen in 26% of CNS PNETs and was significantly associated with longer overall survival. Genes displaying a significant difference in expression levels, between tumours with and without WNT/ß-catenin pathway activation, included several involved in normal CNS development suggesting aberrant pathway activation may be disrupting this process. CONCLUSION: We have identified WNT/ß-catenin pathway status as a marker, which could potentially be used to stratify disease risk for patients with CNS PNET. Gene expression data suggest pathway activation is disrupting normal differentiation in the CNS.


Asunto(s)
Neoplasias del Sistema Nervioso Central/genética , Tumores Neuroectodérmicos Primitivos/genética , Vía de Señalización Wnt/fisiología , beta Catenina/fisiología , Neoplasias del Sistema Nervioso Central/diagnóstico , Neoplasias del Sistema Nervioso Central/metabolismo , Neoplasias del Sistema Nervioso Central/mortalidad , Niño , Dosificación de Gen , Regulación Neoplásica de la Expresión Génica , Humanos , Análisis por Micromatrices , Tumores Neuroectodérmicos Primitivos/diagnóstico , Tumores Neuroectodérmicos Primitivos/metabolismo , Tumores Neuroectodérmicos Primitivos/mortalidad , Estudios Retrospectivos , Análisis de Supervivencia , Transcriptoma , Células Tumorales Cultivadas , Vía de Señalización Wnt/genética , beta Catenina/genética , beta Catenina/metabolismo
14.
Opt Express ; 21(13): 15747-54, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23842361

RESUMEN

A direct UV grating writing technique based on phase-controlled interferometry is proposed and demonstrated in a silica-on-silicon platform, with a wider wavelength detuning range than any previously reported UV writing technology. Electro-optic phase modulation of one beam in the interferometer is used to manipulate the fringe pattern and thus control the parameters of the Bragg gratings and waveguides. Various grating structures with refractive index apodization, phase shifts and index contrasts of up to 0.8 × 10(-3) have been demonstrated. The method offers significant time/energy efficiency as well as simplified optical layout and fabrication process. We have shown Bragg gratings can be made from 1200 nm to 1900 nm exclusively under software control and the maximum peak grating reflectivity only decreases by 3 dBover a 250 nm (~32 THz) bandwidth.

15.
Opt Lett ; 38(5): 727-9, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23455279

RESUMEN

The monolithically integrated all-optical single-sideband (SSB) filter based on photonic Hilbert transform and planar Bragg gratings is proposed and experimentally demonstrated. An SSB suppression of 12 dB at 6 GHz and sideband switching are achieved via thermal tuning. An X-coupler, photonic Hilbert transformer, flat top reflector, and a micro heater are incorporated in a single silicon-on-silica substrate. The device can be thermally tuned by the micro heater on top of the channel waveguide. The device is fabricated using a combination of direct UV grating writing technology and photolithography.

16.
Arts Health ; 15(2): 135-152, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35094642

RESUMEN

BACKGROUND: This paper proposes a framework for studying the potential of museum-led interventions for supporting stroke rehabilitation goals. METHODS: The intervention was based on Kirvevold et al.'s model for interventions for post-stroke wellbeing. Mixed-methods data wqas collected to review benefits in a pilot study, including retrospective video observations for six sessions with four patients; interviews with patients, carers and facilitators; pre-post patient assessments; and facilitator diaries. RESULTS: Systematic analysis of videos showed high levels of concentration and engagement with museum objects, low levels of social interaction, and positive or neutral mood throughout. Thematic qualitative analysis suggested patients felt engaged in meaningful activities, which lifted negative mood, provided positive distraction from the ward, and increased self-esteem, including belief in patient abilities. CONCLUSION: Further research is needed to fully establish the potential of museum-led interventions for stroke rehabilitation.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Rehabilitación de Accidente Cerebrovascular/métodos , Estudios Retrospectivos , Museos , Proyectos Piloto
17.
Br J Cancer ; 107(7): 1144-52, 2012 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-22929883

RESUMEN

BACKGROUND: Medulloblastoma is the most common malignant childhood brain tumour. Aberrant activation of the WNT/ß-catenin pathway occurs in approximately 25% of medulloblastomas. However, its role in medulloblastoma pathogenesis is not understood. METHODS: We have developed a model of WNT/ß-catenin pathway-activated medulloblastoma. Pathway activation was induced in a Myc immortalised cerebellar progenitor cell line through stable expression of Wnt1. In vitro and in vivo analysis was undertaken to understand the effect of pathway activation and identify the potential cell of origin. RESULTS: Tumours that histologically resembled classical medulloblastoma formed in vivo using cells overexpressing Wnt1, but not with the control cell line. Wnt1 overexpression inhibited neuronal differentiation in vitro, suggesting WNT/ß-catenin pathway activation prevents cells terminally differentiating, maintaining them in a more 'stem-like' state. Analysis of cerebellar progenitor cell markers demonstrated the cell line resembled cells from the cerebellar ventricular zone. CONCLUSION: We have developed a cell line with the means of orthotopically modelling WNT/ß-catenin pathway-activated medulloblastoma. We provide evidence of the role pathway activation is playing in tumour pathogenesis and suggest medulloblastomas can arise from cells other than granule cell progenitors. This cell line is a valuable resource to further understand the role of pathway activation in tumorigenesis and for investigation of targeted therapies.


Asunto(s)
Neoplasias Cerebelosas/metabolismo , Genes myc , Meduloblastoma/metabolismo , Células-Madre Neurales/fisiología , Proteína Wnt1/genética , beta Catenina/metabolismo , Animales , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Diferenciación Celular/fisiología , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Neoplasias Cerebelosas/genética , Neoplasias Cerebelosas/patología , Masculino , Meduloblastoma/genética , Meduloblastoma/patología , Ratones , Células-Madre Neurales/metabolismo , Células-Madre Neurales/patología , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Proteína Wnt1/metabolismo , beta Catenina/genética
18.
Osteoporos Int ; 23(1): 171-82, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21365462

RESUMEN

INTRODUCTION: In men, idiopathic osteoporosis (IOP) is often associated with low serum insulin-like growth factor (IGF-1) and reduced bone formation. The characteristics of premenopausal women with IOP are not well defined. We aimed to define the clinical, reproductive, and biochemical characteristics of premenopausal women with unexplained osteoporosis. METHODS: This is a cross-sectional study of 64 women with unexplained osteoporosis, 45 with fragility fractures, 19 with low bone mineral density (BMD; Z-score less than or equal to -2.0) and 40 normal controls. The following are the main outcome measures: clinical and anthropometric characteristics, reproductive history, BMD, gonadal and calciotropic hormones, IGF-1, and bone turnover markers (BTMs). RESULTS: Subjects had lower BMI and BMD than controls, but serum and urinary calcium, serum estradiol, vitamin D metabolites, IGF-1, and most BTMs were similar. Serum parathyroid hormone (PTH) and the resorption marker, tartrate-resistant acid phosphatase (TRAP5b), were significantly higher in both groups of subjects than controls and directly associated in all groups. Serum IGF-1 and all BTMs were directly associated in controls, but the association was not significant after controlling for age. There was no relationship between serum IGF-1 and BTMs in subjects. There were few differences between women with fractures and low BMD. CONCLUSIONS: Higher serum TRAP5b and PTH suggest that increased bone turnover, possibly related to subclinical secondary hyperparathyroidism could contribute to the pathogenesis of IOP. The absence of differences between women with fractures and those with very low BMD indicates that this distinction may not be clinically useful to categorize young women with osteoporosis.


Asunto(s)
Osteoporosis/fisiopatología , Fracturas Osteoporóticas/fisiopatología , Premenopausia/fisiología , Absorciometría de Fotón/métodos , Fosfatasa Ácida/sangre , Adolescente , Adulto , Antropometría/métodos , Biomarcadores/sangre , Índice de Masa Corporal , Densidad Ósea/fisiología , Remodelación Ósea/fisiología , Estudios de Casos y Controles , Estudios Transversales , Dieta , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Isoenzimas/sangre , Persona de Mediana Edad , Osteoporosis/sangre , Fracturas Osteoporóticas/sangre , Hormona Paratiroidea/sangre , Premenopausia/sangre , Historia Reproductiva , Fosfatasa Ácida Tartratorresistente , Adulto Joven
19.
Diabet Med ; 29(3): 321-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21913969

RESUMEN

OBJECTIVE: Risk of severe hypoglycaemia is increased by absence of subjective awareness of hypoglycaemia and reduced by avoidance of minor hypoglycaemia. For many, problems persist despite educational strategies that work for others. We explored psychological factors that might inhibit the efforts of an individual in hypoglycaemia avoidance. METHODS: People with Type 1 diabetes and hypoglycaemia unawareness gave semi-structured interviews exploring their perceptions and experiences of their condition. Identified factors were grouped into categories and analysed to establish links and form a grounded theory in a constant comparative analysis. A questionnaire was devised from the qualitative analysis to identify patients with problematic beliefs about their hypoglycaemia. RESULTS: Saturation (no new themes emerging) was reached with 17 patients. Responses fell into two groups: high concern and low concern regarding hypoglycaemia unawareness. Those in the first group described severe hypoglycaemia as aversive and wanted to regain awareness. The second group included three patients in whom unawareness was not associated with severe hypoglycaemia, nevertheless unhelpful attitudes which inhibited hypoglycaemia avoidance were expressed. Responses from this group fell into categories: (1) normalizing the presence of unawareness; (2) underestimating its consequences; (3) wanting to avoiding the 'sick role'; and (4) overestimating the consequences of hyperglycaemia. CONCLUSIONS: A qualitative analysis of patient interviews identified deficits in education, technology and motivation in hypoglycaemia unawareness. Interventions can therefore be tailored to target underlying problems that prevent individual patients from regaining awareness. A brief assessment tool was devised to categorize patients' hypoglycaemia unawareness accordingly. Psychological interventions should be developed to address the problems of 'low concern' regarding hypoglycaemia unawareness.


Asunto(s)
Concienciación , Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 1/psicología , Hipoglucemia/psicología , Hipoglucemiantes/efectos adversos , Insulina/uso terapéutico , Actitud Frente a la Salud , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Femenino , Hemoglobina Glucada/efectos de los fármacos , Humanos , Hipoglucemia/sangre , Hipoglucemia/inducido químicamente , Hipoglucemia/complicaciones , Hipoglucemia/prevención & control , Hipoglucemiantes/administración & dosificación , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Factores de Riesgo , Rol del Enfermo , Encuestas y Cuestionarios
20.
Educ Psychol Meas ; 82(2): 225-253, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35185158

RESUMEN

Test fairness is critical to the validity of group comparisons involving gender, ethnicities, culture, or treatment conditions. Detection of differential item functioning (DIF) is one component of efforts to ensure test fairness. The current study compared four treatments for items that have been identified as showing DIF: deleting, ignoring, multiple-group modeling, and modeling DIF as a secondary dimension. Results of this study provide indications about which approach could be applied for items showing DIF for a wide range of testing environments requiring reliable treatment.

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