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1.
Nature ; 576(7786): 228-231, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31802006

RESUMEN

The prediction of a supersonic solar wind1 was first confirmed by spacecraft near Earth2,3 and later by spacecraft at heliocentric distances as small as 62 solar radii4. These missions showed that plasma accelerates as it emerges from the corona, aided by unidentified processes that transport energy outwards from the Sun before depositing it in the wind. Alfvénic fluctuations are a promising candidate for such a process because they are seen in the corona and solar wind and contain considerable energy5-7. Magnetic tension forces the corona to co-rotate with the Sun, but any residual rotation far from the Sun reported until now has been much smaller than the amplitude of waves and deflections from interacting wind streams8. Here we report observations of solar-wind plasma at heliocentric distances of about 35 solar radii9-11, well within the distance at which stream interactions become important. We find that Alfvén waves organize into structured velocity spikes with duration of up to minutes, which are associated with propagating S-like bends in the magnetic-field lines. We detect an increasing rotational component to the flow velocity of the solar wind around the Sun, peaking at 35 to 50 kilometres per second-considerably above the amplitude of the waves. These flows exceed classical velocity predictions of a few kilometres per second, challenging models of circulation in the corona and calling into question our understanding of how stars lose angular momentum and spin down as they age12-14.

2.
BMC Public Health ; 24(1): 2010, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39068394

RESUMEN

BACKGROUND: Weather and season are determinants of physical activity. Therefore, it is important to ensure built environments are designed to mitigate negative impacts of weather and season on pedestrians to prevent these losses. This scoping review aims to identify built environment audits of pedestrian environments developed for use during a specific weather condition or season. Secondly, this review aims to investigate gaps in the inclusion of relevant weather mitigating built environment features in pedestrian environment audit tools. METHODS: Following a standard protocol, a systematic search was executed in CINAHL, Medline and Web of Science to identify built environment audit tools of pedestrian spaces. These databases were chosen since they are well-known to comprehensively cover health as well as multi-disciplinary research publications relevant to health. Studies were screened, and data were extracted from selected documents by two independent reviewers (e.g., psychometric properties and audit items included). Audit items were screened for the inclusion of weather mitigating built environment features, and the tool's capacity to measure temperature, precipitation, seasonal and sustainability impacts on pedestrians was calculated. RESULTS: The search returned 2823 documents. After screening and full text review, 27 articles were included. No tool was found that was developed specifically for use during a specific weather condition or season. Additionally, gaps in the inclusion of weather mitigating items were found for all review dimensions (thermal comfort, precipitation, seasonal, and sustainability items). Poorly covered items were: (1) thermal comfort related (arctic entry presence, materials, textures, and colours of buildings, roads, sidewalk and furniture, and green design features); (2) precipitation related (drain presence, ditch presence, hazards, and snow removal features); (3) seasonal features (amenities, pedestrian scale lighting, and winter destinations and aesthetics); and (4) sustainability features (electric vehicle charging stations, renewable energy, car share, and bike share facilities). CONCLUSIONS: Current built environment audit tools do not adequately include weather / season mitigating items. This is a limitation as it is important to investigate if the inclusion of these items in pedestrian spaces can promote physical activity during adverse weather conditions. Because climate change is causing increased extreme weather events, a need exists for the development of a new built environment audit tool that includes relevant weather mitigating features.


Asunto(s)
Entorno Construido , Peatones , Tiempo (Meteorología) , Humanos , Estaciones del Año , Caminata/estadística & datos numéricos , Planificación Ambiental
3.
Cereb Cortex ; 32(12): 2555-2574, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34730185

RESUMEN

Noninvasive diffusion-weighted magnetic resonance imaging (dMRI) can be used to map the neural connectivity between distinct areas in the intact brain, but the standard resolution achieved fundamentally limits the sensitivity of such maps. We investigated the sensitivity and specificity of high-resolution postmortem dMRI and probabilistic tractography in rhesus macaque brains to produce retinotopic maps of the lateral geniculate nucleus (LGN) and extrastriate cortical visual area V5/MT based on their topographic connections with the previously established functional retinotopic map of primary visual cortex (V1). We also replicated the differential connectivity of magnocellular and parvocellular LGN compartments with V1 across visual field positions. Predicted topographic maps based on dMRI data largely matched the established retinotopy of both LGN and V5/MT. Furthermore, tractography based on in vivo dMRI data from the same macaque brains acquired at standard field strength (3T) yielded comparable topographic maps in many cases. We conclude that tractography based on dMRI is sensitive enough to reveal the intrinsic organization of ordered connections between topographically organized neural structures and their resultant functional organization.


Asunto(s)
Corteza Visual , Vías Visuales , Animales , Imagen de Difusión por Resonancia Magnética , Cuerpos Geniculados/diagnóstico por imagen , Macaca mulatta , Corteza Visual/diagnóstico por imagen , Vías Visuales/diagnóstico por imagen
4.
Nature ; 536(7614): 63-6, 2016 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-27488798

RESUMEN

Quantum computers can solve certain problems more efficiently than any possible conventional computer. Small quantum algorithms have been demonstrated on multiple quantum computing platforms, many specifically tailored in hardware to implement a particular algorithm or execute a limited number of computational paths. Here we demonstrate a five-qubit trapped-ion quantum computer that can be programmed in software to implement arbitrary quantum algorithms by executing any sequence of universal quantum logic gates. We compile algorithms into a fully connected set of gate operations that are native to the hardware and have a mean fidelity of 98 per cent. Reconfiguring these gate sequences provides the flexibility to implement a variety of algorithms without altering the hardware. As examples, we implement the Deutsch-Jozsa and Bernstein-Vazirani algorithms with average success rates of 95 and 90 per cent, respectively. We also perform a coherent quantum Fourier transform on five trapped-ion qubits for phase estimation and period finding with average fidelities of 62 and 84 per cent, respectively. This small quantum computer can be scaled to larger numbers of qubits within a single register, and can be further expanded by connecting several such modules through ion shuttling or photonic quantum channels.

5.
BMC Public Health ; 22(1): 1241, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35733102

RESUMEN

BACKGROUND: Several jurisdictions have introduced nutrient warning front of pack (FoP) labels in an effort to curb consumption of ultra-processed foods and beverages high in free sugars (sugars added to foods and beverages, and sugars naturally present in honey, syrups, fruit juices and fruit juice concentrates). This study aimed to explore consumer understanding and perceptions of FoP warning labels that convey different nutritional and health information messages regarding the consumption of sugary drinks. METHODS: Sixteen focus groups were held with 4-8 young adults per group (aged 18-24; n = 105 participants in total) stratified by education level, location (rural centres, large cities) and gender (males, females) to ensure diversity. Labels shown to participants during group discussions included text warning labels of health effects, exercise equivalents, calorie/kilojoule information and sugar content as a "high in" label and as teaspoons (text and pictograms). Thematic analysis was undertaken. RESULTS: Four themes were identified related to participants' perceived effectiveness of labels: the extent to which labels were perceived to be useful, relevant and credible; the extent to which a label elicited shock or disgust (perceived aversiveness); the extent to which the label message was resistant to self-exemption; and participants' perceived potential of the label to reduce purchasing and consumption behaviour. Across all four themes, labels communicating the number of teaspoons of sugar in a sugary drink (whether by text or pictogram) were perceived as the most impactful, resistant to self-exemption and to have the greatest potential to reduce consumption, with enhanced reactions to the pictogram label. Labels depicting health effects, exercise equivalents, calorie/kilojoule information or a general 'high in sugar' warning were perceived by consumers to be less effective in one or more themes. CONCLUSIONS: Labels conveying the amount of sugar in a beverage in teaspoons were perceived as highly factual, relatable and interpretable, and as having the greatest potential to impact consumption attitudes and intentions. Further quantitative studies are required to compare the potential effectiveness of the teaspoons of sugar labels in reducing purchasing and consumption behaviour than other alternative warning labels, such as health effects or "high in" sugar labels.


Asunto(s)
Etiquetado de Alimentos , Bebidas Azucaradas , Bebidas , Comportamiento del Consumidor , Femenino , Humanos , Masculino , Azúcares , Adulto Joven
6.
West Afr J Med ; 39(1): 83-89, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35167198

RESUMEN

BACKGROUND: Studies have demonstrated the role of sputum as a site of severe acute respiratory syndrome-coronavirus-2 (SARSCoV-2) transmission. However, there is limited literature on the virucidal efficacy of oral antiseptics against SARS-CoV-2 virus. This study investigated the virucidal efficacy of three oral-antiseptics compared to a placebo-control in the sputum of SARS-CoV-2 infected individuals. METHODOLOGY: A pilot study of adults with SARS-CoV-2 positive results, as determined by reverse transcription-polymerase chain reaction (RT-PCR) of <7 days. The oral antiseptics investigated were: Hexetidine (0.1% w/v); Thymol (0.063% w/v) and H2O2(1.5%) compared to de-mineralized sterile water (Placebo-control). The primary outcome measure was the proportion of negative RT-PCR results at 15-mins, 30-mins, 1-hour, 2-hours and 4-hours After Oral antiseptics Interventions (AOI) compared to the placebo-control. Statistical analysis was done using STATA 15.0 software with p-values of <0.05 considered statistically significant. RESULTS: Data from a total of 66 participants that were RT-PCR SARS-CoV-2 positive at baseline (0-min) was analysed. At 15-mins AOI, the highest proportion of negativation from sputum samples was observed in the Hexedine group, with 69.2% of the baseline PCR positive cases converting to negative compared to 46.7% in the placebo-control group. In addition, H2O2 demonstrated efficacy at 2-hours AOI compared to placebo-control (62.5% vs 37.5% respectively) and other oral-antiseptics. Across all time-points, the oral-antiseptic groups compared to the placebo-control group, there was no statistically significant difference in the proportion of sputum samples which converted to a negative status (p>0.05). CONCLUSION: The findings in this study suggest there was no significant difference in the proportion of participants who converted to a negative sputum status across the treatment groups at various time points. Future studies could compare the cycle threshold (ct) viral titre values of sputum samples to determine quantitative differences.


CONTEXTE: Des études ont démontré le rôle des expectorations comme un site de transmission du syndrome respiratoire aigu sévère-coronavirus- 2 (SRAS-CoV-2). Cependant, il existe peu de documentation sur l'efficacité virucide des antiseptiques oraux contre le virus du SRASCoV-2. Cette étude a examiné l'efficacité virucide de trois antiseptiques oraux par rapport à un contrôle placebo dans les expectorations de personnes infectées par le SRAS-CoV-2. MÉTHODOLOGIE: Une étude pilote menée auprès d'adultes dont les résultats sont positifs pour le SRAS-CoV-2, tels que déterminés par la réaction en chaîne de la polymérase par transcription inverse (RT-PCR) pendant 7 jours. Les antiseptiques oraux étudiés étaient : Hexetidine (0,1% p/v) ; Thymol (0,063% p/v) et H2O2 (1,5%) par rapport à l'eau stérile déminéralisée (Placebo-contrôle). Le principal critère d'évaluation était la proportion de résultats RT-PCR négatifs 15 minutes, 30 minutes, 1 heure, 2 heures et 4 heures après les interventions antiseptiques orales (AOI) par rapport au contrôle placebo. L'analyse statistique a été réalisée à l'aide du logiciel STATA 15.0, les valeurs p de <0,05 étant considérées comme statistiquement significatives. RÉSULTATS: Les données d'un total de 66 participants qui étaient positifs à la RT-PCR SARS-CoV-2 au départ (0 minute) ont été analysées. Au bout de 15 minutes, la plus forte proportion de négativation des échantillons d'expectoration a été observée dans le groupe Hexedine, 69,2 % des cas positifs au départ par PCR devenant négatifs, contre 46,7 % dans le groupe témoin placebo. En outre, l'H2O2 a démontré son efficacité à 2 heures après l'apparition de la maladie par rapport au groupe placebo (62,5 % contre 37,5 % respectivement) et aux autres antiseptiques oraux. Pour tous les points temporels, les groupes d'antiseptiques oraux comparés au groupe placebo n'ont pas présenté de différence statistiquement significative dans la proportion d'échantillons d'expectoration qui sont devenus négatifs (p>0,05). CONCLUSION: Les résultats de cette étude suggèrent qu'il n'y a pas de différence significative dans la proportion de participants qui sont passés à un statut négatif d'expectoration dans les groupes de traitement à différents moments. Les études futures pourraient comparer les valeurs du titre viral au seuil de cycle (ct) des échantillons d'expectoration afin de déterminer les différences quantitatives. MOTS CLÉS: SRAS-CoV-2, antiseptiques oraux, hexétidine, peroxyde d'hydrogène.


Asunto(s)
Antiinfecciosos Locales , COVID-19 , Adulto , Antiinfecciosos Locales/farmacología , Hexetidina , Humanos , Peróxido de Hidrógeno , Boca , Proyectos Piloto , SARS-CoV-2 , Timol
7.
Osteoporos Int ; 32(3): 515-527, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32930851

RESUMEN

The associations between objective measures of sleep duration and bone outcomes in older men are unknown. No consistent, significant association was identified between sleep duration and bone mineral density (BMD) in the current analysis. However, future research should determine if vitamin D status modifies this relationship. INTRODUCTION: Prior studies, predominantly in women, reported that long and short self-reported sleep duration are associated with lower BMD. Associations between actigraphy-determined sleep duration and BMD or bone turnover markers (BTMs) in older men are unknown. METHODS: Men in The Osteoporotic Fractures in Men (MrOS) Study with wrist actigraphy and concurrent BMD assessment but without comorbidities affecting bone health were included. Sleep duration was considered as a continuous (N = 1926) and dichotomized variable where men were classified as getting the recommended (7-8 h/night; N = 478) or short (< 6 h/night; N = 577) sleep. The cross-sectional association between BMD, BTMs, and sleep duration was examined using a t test or linear regression, where appropriate, in unadjusted and adjusted models. RESULTS: There were no clinically or statistically significant differences in BMD at the L-spine, total hip, or femoral neck between men getting the recommended vs. short sleep duration, using actigraphy or self-reported sleep duration (all p ≥ 0.07). When sleep duration was considered as a continuous variable, femoral neck BMD was higher in men with longer self-reported sleep duration (ß = 0.006 ±0.003, p = 0.02), but this was not significant after further adjustment. In men with low 25OHD (< 20 ng/mL), longer actigraphy-determined sleep duration was associated with higher total hip BMD (ß = 0.016 ± 0.008; p = 0.04). Sleep duration and BTMs were not associated. CONCLUSION: Sleep duration was not associated with hip or L-spine BMD or BTMs in older men. Future research should determine if vitamin D status or other factors modify this relationship.


Asunto(s)
Densidad Ósea , Cuello Femoral , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Sueño , Vitamina D
8.
BMC Geriatr ; 21(1): 44, 2021 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-33435877

RESUMEN

BACKGROUND: Older adults with obesity residing in rural areas have reduced access to weight management programs. We determined the feasibility, acceptability and preliminary outcomes of an integrated technology-based health promotion intervention in rural-living, older adults using remote monitoring and synchronous video-based technology. METHODS: A 6-month, non-randomized, non-blinded, single-arm study was conducted from October 2018 to May 2020 at a community-based aging center of adults aged ≥65 years with a body mass index (BMI) ≥30 kg/m2. Weekly dietitian visits focusing on behavior therapy and caloric restriction and twice-weekly physical therapist-led group strength, flexibility and balance training classes were delivered using video-conferencing to participants in their homes. Participants used a Fitbit Alta HR for remote monitoring with data feedback provided by the interventionists. An aerobic activity prescription was provided and monitored. RESULTS: Mean age was 72.9±3.9 years (82% female). Baseline anthropometric measures of weight, BMI, and waist circumference were 97.8±16.3 kg, 36.5±5.2 kg/m2, and 115.5±13.0 cm, respectively. A total of 142 participants were screened (n=27 ineligible), and 53 consented. There were nine dropouts (17%). Overall satisfaction with the trial (4.7+ 0.6, scale: 1 (low) to 5 (high)) and with Fitbit (4.2+ 0.9) were high. Fitbit was worn an average of 81.7±19.3% of intervention days. In completers, mean weight loss was 4.6±3.5 kg or 4.7±3.5% (p< 0.001). Physical function measures of 30-s sit-to-stand repetitions increased from 13.5±5.7 to 16.7±5.9 (p< 0.001), 6-min walk improved by 42.0±77.3 m (p=0.005) but no differences were observed in gait speed or grip strength. Subjective measures of late-life function improved (3.4±4.7 points, p< 0.001). CONCLUSIONS: A technology-based obesity intervention is feasible and acceptable to older adults with obesity and may lead to weight loss and improved physical function. CLINICAL TRIAL REGISTRATION: Registered on Clinicaltrials.gov # NCT03104205 . Registered on April 7, 2017. First participant enrolled on October 1st, 2018.


Asunto(s)
Obesidad , Pérdida de Peso , Anciano , Índice de Masa Corporal , Estudios de Factibilidad , Femenino , Humanos , Masculino , Obesidad/diagnóstico , Obesidad/epidemiología , Obesidad/terapia , Tecnología
9.
West Afr J Med ; Vol. 38(11): 1058-1064, 2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34919362

RESUMEN

BACKGROUND: Health behavior theories suggest that knowledge about the health risks of the behavior precedes behavior change. Tobacco control messages aim to promote knowledge of health risks associated with tobacco use and encourage smoking cessation behaviors such as quit attempts and intention to quit. This study assessed the relationship between exposure to Anti-Tobacco Messaging (ATM) and quit attempts among adolescents and young adults in Lagos, Nigeria. METHODS: This was an online cross-sectional survey of 947 participants aged between 15-35 years. The survey obtained sociodemographic information, smoking status, exposure to ATM, intention to quit and quit attempts in the past 12-months. Logistic regression analysis was used to identify the relationship between exposure to ATM and quit attempts; pvalues <0.05 were considered significant. Statistical analysis was done using STATA-15.0 software. RESULTS: The mean age of respondents was 23.4 years (SD:4.0). Less than one-third of the respondents were smokers (23.4%). The most common source of ATM were digital sources (online and social media - 29.6%). Based on the multivariable logistic regression model, younger age (p:0.03) and an intention to quit (p: <0.001) were significantly associated with a quit attempt. Exposure to ATM in the past 12 months was also significantly associated with higher odds of a quit attempt (OR:5.33; 95% CI: 1.26,22.60; p: 0.02). CONCLUSION: Our findings suggest an association between exposure to ATM and quit attempts among adolescent and young adult smokers in Lagos State, Nigeria. Policymakers should consider measures aimed at promoting tobacco control education and improving access to smoking cessation services.


CONTEXTE: Les théories du comportement en matière de santé suggèrent que la connaissance des risques sanitaires du comportement précède le changement de comportement. Les messages de lutte contre le tabagisme visent à promouvoir la connaissance des risques pour la santé associés au tabagisme et à encourager les comportements de renoncement au tabac tels que les tentatives d'abandon et l'intention d'abandonner. Cette étude a évalué la relation entre l'exposition aux messages antitabac (MTA) et les tentatives d'arrêt du tabac chez les adolescents et les jeunes adultes de Lagos, au Nigeria. MÉTHODES: Il s'agissait d'une enquête transversale en ligne auprès de 947 participants âgés de 15 à 35 ans. L'enquête a permis d'obtenir des informations sociodémographiques, le statut tabagique, l'exposition au MTA, l'intention d'arrêter et les tentatives d'arrêt au cours des 12 derniers mois. Une analyse de régression logistique a été utilisée pour identifier la relation entre l'exposition à la GTA et les tentatives d'abandon ; les valeurs p <0,05 ont été considérées comme significatives. L'analyse statistique a été réalisée à l'aide du logiciel STATA-15.0. RÉSULTATS: L'âge moyen des répondants était de 23,4 ans (écarttype:4,0). Moins d'un tiers des répondants étaient fumeurs (23,4%). La source de DAB la plus courante était les sources numériques (médias en ligne et sociaux-29, 6%). D'après le modèle de régression logistique multivariable, un âge plus jeune (p: 0,03) et une intention d'arrêter de fumer (p:<0,001) étaient significativement associés à une tentative d'arrêt. L'exposition à la GTA au cours des 12 derniers mois était également associée de manière significative à une probabilité plus élevée de tentative d'abandon (OR:5,33;IC à 95%: 1,26,22,60; p:0,02). CONCLUSION: Nos résultats suggèrent une association entre l'exposition à la GTA et les tentatives d'arrêt chez les fumeurs adolescents et jeunes adultes de l'État de Lagos, au Nigeria. Les décideurs politiques devraient envisager des mesures visant à promouvoir l'éducation à la lutte antitabac et à améliorer l'accès aux services d'aide au sevrage tabagique. Mots clés: Adolescent, Intention d'arrêter de fumer, Tentative d'arrêt du tabac, Jeunes, Tabac.


Asunto(s)
Nicotiana , Investigación , Adolescente , Adulto , Estudios Transversales , Humanos , Nigeria , Uso de Tabaco , Adulto Joven
10.
Osteoporos Int ; 31(11): 2269-2270, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32965511

RESUMEN

Following the work of Avenell et al. that has raised concerns about the integrity of the Yamaguchi Osteoporosis Prevention Study (YOPS) conducted by Ishida and Kawai we issue here an adjustment to all meta-analysis estimates that contained this work within our systematic review.

11.
Br J Surg ; 106(2): e91-e102, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30620076

RESUMEN

BACKGROUND: The WHO Surgical Safety Checklist improves surgical outcomes, but evidence and theoretical frameworks for successful implementation in low-income countries remain lacking. Based on previous research in Madagascar, a nationwide checklist implementation in Benin was designed and evaluated longitudinally. METHODS: This study had a longitudinal embedded mixed-methods design. The well validated Consolidated Framework for Implementation Research (CFIR) was used to structure the approach and evaluate the implementation. Thirty-six hospitals received 3-day multidisciplinary training and 4-month follow-up. Seventeen hospitals were sampled purposively for evaluation at 12-18 months. The primary outcome was sustainability of checklist use at 12-18 months measured by questionnaire. Secondary outcomes were CFIR-derived implementation outcomes, measured using the WHO Behaviourally Anchored Rating Scale (WHOBARS), safety questionnaires and focus groups. RESULTS: At 12-18 months, 86·0 per cent of participants (86 of 100) reported checklist use compared with 31·1 per cent (169 of 543) before training and 88·8 per cent (158 of 178) at 4 months. There was high-fidelity use (median WHOBARS score 5·0 of 7; use of basic safety processes ranged from 85·0 to 99·0 per cent), and high penetration shown by a significant improvement in hospital safety culture (adapted Human Factors Attitude Questionnaire scores of 76·7, 81·1 and 82·2 per cent before, and at 4 and 12-18 months after training respectively; P < 0·001). Acceptability, adoption, appropriateness and feasibility scored 9·6-9·8 of 10. This approach incorporated 31 of 36 CFIR implementation constructs successfully. CONCLUSION: This study shows successfully sustained nationwide checklist implementation using a validated implementation framework.


Asunto(s)
Lista de Verificación/métodos , Atención a la Salud/normas , Implementación de Plan de Salud/métodos , Seguridad del Paciente/normas , Mejoramiento de la Calidad/estadística & datos numéricos , Benin , Lista de Verificación/estadística & datos numéricos , Estudios de Seguimiento , Adhesión a Directriz/estadística & datos numéricos , Hospitales/normas , Humanos , Estudios Longitudinales , Evaluación de Programas y Proyectos de Salud , Encuestas y Cuestionarios , Organización Mundial de la Salud
12.
Osteoporos Int ; 30(8): 1543-1559, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31076817

RESUMEN

Vitamin K may affect bone mineral density and fracture incidence. Since publication of a previous systematic review the integrity of some of the previous evidence has been questioned and further trials have been published. Therefore an update to the systematic review was required. INTRODUCTION: This systematic review was designed to assess the effectiveness of oral vitamin K supplementation for increasing bone mineral density and reducing fractures in adults. METHODS: MEDLINE, EMBASE, CENTRAL, CINAHL, clinicaltrials.gov, and WHO-ICTRP were searched for eligible trials. Randomised controlled trials assessing oral vitamin K supplementation that assessed bone mineral density or fractures in adult populations were included. A total of 36 studies were identified. Two independent reviewers extracted data using a piloted extraction form. RESULTS: For post-menopausal or osteoporotic patients, meta-analysis showed that the odds of any clinical fracture were lower for vitamin K compared to controls (OR, 0.72, 95%CI 0.55 to 0.95). Restricting the analysis to low risk of bias trials reduced the OR to 0.76 (95%CI, 0.58 to 1.01). There was no difference in vertebral fractures between the groups (OR 0.96, 95%CI 0.83 to 1.11). In the bone mineral density meta-analysis, percentage change from baseline at the lumbar spine was higher at 1 year (MD 0.93, 95%, CI - 0.02 to 1.89) and 2 years (MD 1.63%, 95%CI 0.10 to 3.16) for vitamin K compared to controls; however, removing trials at high risk of bias tended to result in smaller differences that were not statistically significant. At 6 months, it was higher in the hip (MD 0.42%, 95%CI 0.01 to 0.83) and femur (MD 0.29%, 95%CI 0.17 to 0.42). There was no significant difference at other anatomical sites. CONCLUSIONS: For post-menopausal or osteoporotic patients, there is no evidence that vitamin K affects bone mineral density or vertebral fractures; it may reduce clinical fractures; however, the evidence is insufficient to confirm this. There are too few trials to draw conclusions for other patient groups.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Fracturas Osteoporóticas/prevención & control , Vitamina K/farmacología , Suplementos Dietéticos , Humanos , Osteoporosis/tratamiento farmacológico , Osteoporosis/fisiopatología , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Fracturas de la Columna Vertebral/prevención & control , Vitamina K/uso terapéutico
13.
Osteoporos Int ; 30(12): 2485-2493, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31446439

RESUMEN

We describe the time course of bone formation marker (P1NP) decline in men exposed to ~ 3 weeks of sleep restriction with concurrent circadian disruption. P1NP declined within 10 days and remained lower with ongoing exposure. These data suggest even brief exposure to sleep and circadian disruptions may disrupt bone metabolism. INTRODUCTION: A serum bone formation marker (procollagen type 1 N-terminal, P1NP) was lower after ~ 3 weeks of sleep restriction combined with circadian disruption. We now describe the time course of decline. METHODS: The ~ 3-week protocol included two segments: "baseline," ≥ 10-h sleep opportunity/day × 5 days; "forced desynchrony" (FD), recurring 28 h day (circadian disruption) with sleep restriction (~ 5.6-h sleep per 24 h). Fasted plasma P1NP was measured throughout the protocol in nine men (20-59 years old). We tested the hypothesis that PINP would steadily decline across the FD intervention because the magnitude of sleep loss and circadian misalignment accrued as the protocol progressed. A piecewise linear regression model was used to estimate the slope (ß) as ΔP1NP per 24 h with a change point mid-protocol to estimate the initial vs. prolonged effects of FD exposure. RESULTS: Plasma P1NP levels declined significantly within the first 10 days of FD ([Formula: see text] = - 1.33 µg/L per 24 h, p < 0.0001) and remained lower than baseline with prolonged exposure out to 3 weeks ([Formula: see text] = - 0.18 µg/L per 24 h, p = 0.67). As previously reported, levels of a bone resorption marker (C-telopeptide (CTX)) were unchanged. CONCLUSION: Sleep restriction with concurrent circadian disruption induced a relatively rapid decline in P1NP (despite no change in CTX) and levels remained lower with ongoing exposure. These data suggest (1) even brief sleep restriction and circadian disruption can adversely affect bone metabolism, and (2) there is no P1NP recovery with ongoing exposure that, taken together, could lead to lower bone density over time.


Asunto(s)
Relojes Circadianos/fisiología , Osteogénesis/fisiología , Fragmentos de Péptidos/sangre , Procolágeno/sangre , Privación de Sueño/fisiopatología , Trastornos del Sueño del Ritmo Circadiano/fisiopatología , Adulto , Biomarcadores/sangre , Colágeno Tipo I/sangre , Humanos , Masculino , Persona de Mediana Edad , Péptidos/sangre , Sueño/fisiología , Privación de Sueño/sangre , Trastornos del Sueño del Ritmo Circadiano/sangre , Adulto Joven
14.
Osteoporos Int ; 30(10): 2087-2098, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31139855

RESUMEN

Methodological limitations preclude determination of the association between sleep duration and bone mineral density (BMD) from existing literature. This was the first study to use objective sleep duration to determine its association with BMD. Nocturnal sleep duration, assessed objectively (actigraphy) or subjectively (questionnaire), was not independently associated with BMD in postmenopausal women. INTRODUCTION: Both long and short self-reported sleep durations are associated with low bone mineral density (BMD) in men and women. The association between sleep duration measured by actigraphy and BMD in postmenopausal women is unknown. METHODS: The Study of Osteoporotic Fractures (SOF) ancillary sleep study was used to determine the association between sleep duration and BMD at the total hip and femoral neck in postmenopausal women ≥ 75 years old. Sleep duration was assessed by wrist actigraphy (average 4 nights) and questionnaire. BMD was compared between postmenopausal women with short (< 6 h/night) vs. NIH-recommended (7-8 h/night) sleep durations. Data were analyzed using a 2-sample t test (unadjusted) and multivariate regression model (adjusted). Simple linear regression was used to estimate the difference in BMD per additional hour of sleep when sleep duration was considered as a continuous, rather than dichotomized, variable. RESULTS: Total hip BMD was higher in women with actigraphically assessed shorter sleep duration in unadjusted models only. No clinically or statistically significant differences in total hip or femoral neck BMD were observed according to nocturnal sleep duration after adjusting for body mass index (BMI) in dichotomized (N = 874) or continuous (N = 1624) sleep duration models or when subjective sleep duration was used. When sleep duration included daytime naps, longer sleep duration was associated with lower total hip BMD (ß = - 0.005, p = 0.04). CONCLUSIONS: Nocturnal sleep duration, whether assessed objectively (actigraphy) or subjectively (questionnaire), was not independently associated with BMD in older postmenopausal women.


Asunto(s)
Densidad Ósea/fisiología , Posmenopausia/fisiología , Sueño/fisiología , Absorciometría de Fotón/métodos , Actigrafía/métodos , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Femenino , Cuello Femoral/fisiología , Articulación de la Cadera/fisiología , Humanos , Osteoporosis Posmenopáusica/fisiopatología , Autoinforme , Encuestas y Cuestionarios , Factores de Tiempo
15.
J Hum Nutr Diet ; 32(2): 175-184, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30412327

RESUMEN

BACKGROUND: Elimination diets required for the management of food allergies increase the risk for poor growth in children. Currently, no worldwide data exist on this topic and limited published data exist on the impact of atopic comorbidity, type of allergy and foods eliminated on growth. We therefore set out to perform a worldwide survey on growth and impacting factors in food allergic children. METHODS: A prospective growth survey was performed of children (aged 0-16 years) on an elimination diet with confirmed immunoglobulin (Ig)E and non-IgE mediated food allergies. Data collected included: weight-for-age, weight-for-height, height-for-age, head circumference, body mass index, type of food allergy and eliminated foods, allergic comorbidities and replacement milk/breast milk. Multivariable regression analysis was used to establish factors that affected growth. RESULTS: Data from 430 patients from twelve allergy centres were analysed: median age at diagnosis and data collection was 8 months and 23 months, respectively. Pooled data indicated that 6% were underweight, 9% were stunted, 5% were undernourished and 8% were overweight. Cow's milk elimination lead to a lower weight-for-height Z-scores than other food eliminations and mixed IgE and non-IgE mediated allergy had lower height-for-age Z-scores than IgE mediated allergy. Children with only non-IgE mediated allergies had lower weight-for-height and body mass index. Atopic comorbidities did not impact on growth. CONCLUSIONS: Stunting is more common in children with food allergies than low weight. Children particularly at risk of poor growth are those with non-IgE and mixed IgE and non-IgE mediated allergies, as well as those with cow's milk allergy.


Asunto(s)
Estatura/fisiología , Peso Corporal/fisiología , Hipersensibilidad a los Alimentos/fisiopatología , Trastornos del Crecimiento/etiología , Delgadez/etiología , Adolescente , Niño , Desarrollo Infantil/fisiología , Preescolar , Femenino , Hipersensibilidad a los Alimentos/complicaciones , Gráficos de Crecimiento , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Análisis de Regresión , Encuestas y Cuestionarios
16.
Eur Cell Mater ; 35: 255-267, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29714398

RESUMEN

High hopes have been pinned on regenerative medicine strategies in order to prevent the progression of cartilage damage to osteoarthritis, particularly by autologous chondrocyte implantation (ACI). The loss of chondrocyte phenotype during in vitro monolayer expansion, a necessary step to obtain sufficient cell numbers, may be a key limitation in ACI. In this study, it was determined whether a shorter monolayer expansion approach could improve chondrogenic differentiation. The effects of two supplement types, foetal bovine serum (FBS) and Stemulate™ (a commercial source of human platelet lysate), on the expansion and re-differentiation potential of human chondrocytes, isolated from five individuals, were compared. Chondrocytes were expanded with 10 % FBS or 10 % Stemulate™. Pellets were cultured for 28 d in chondrogenic differentiation medium and assessed for the presence of cartilage matrix molecules and genes associated with chondrogenicity. Stemulate™ significantly enhanced the proliferation rate [average population doubling times: FBS, 25.07 ± 6.98 d (standard error of the mean, SEM) vs. Stemulate™, 13.10 ± 2.57 d (SEM)]. Sulphated glycosaminoglycans (sGAG), total collagen and qRT-PCR analyses of cartilage genes showed that FBS-expanded chondrocytes demonstrated significantly better chondrogenic capacity than Stemulate™-expanded chondrocytes. Histologically, FBS-expanded chondrocyte pellets appeared to be more stable, with a more intense staining for toluidine blue, indicating a greater chondrogenic capacity. Although Stemulate™ positively influenced chondrocyte proliferation, it had a negative effect on chondrogenic differentiation potential. This suggested that, in the treatment of cartilage defects, Stemulate™ might not be the ideal supplement for expanding chondrocytes (which maintained a chondrocyte phenotype) and, hence, for cell therapies (including ACI).


Asunto(s)
Plaquetas/metabolismo , Cartílago Articular/citología , Condrocitos/citología , Condrogénesis , Anciano , Recuento de Células , Diferenciación Celular , Proliferación Celular , Tratamiento Basado en Trasplante de Células y Tejidos , Células Cultivadas , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Perfilación de la Expresión Génica , Glicosaminoglicanos/metabolismo , Humanos , Persona de Mediana Edad
17.
Br J Dermatol ; 179(3): 599-608, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29573391

RESUMEN

BACKGROUND: Hyperhidrosis is uncontrollable excessive sweating, which occurs at rest, regardless of temperature. The symptoms of hyperhidrosis can significantly affect quality of life. OBJECTIVES: To undertake a systematic review of the clinical effectiveness and safety of treatments available in secondary care for the management of primary hyperhidrosis. METHODS: Fifteen databases (including trial registers) were searched to July 2016 to identify studies of secondary-care treatments for primary hyperhidrosis. For each intervention randomized controlled trials (RCTs) were included where available; where RCT evidence was lacking, nonrandomized trials or large prospective case series were included. Outcomes of interest included disease severity, sweat rate, quality of life, patient satisfaction and adverse events. Trial quality was assessed using a modified version of the Cochrane Risk of Bias tool. Results were pooled in pairwise meta-analyses where appropriate, otherwise a narrative synthesis was presented. RESULTS: Fifty studies were included in the review: 32 RCTs, 17 nonrandomized trials and one case series. The studies varied in terms of population, intervention and methods of outcome assessment. Most studies were small, at high risk of bias and poorly reported. The interventions assessed were iontophoresis, botulinum toxin (BTX) injections, anticholinergic medications, curettage and newer energy-based technologies that damage the sweat gland. CONCLUSIONS: The evidence for the effectiveness and safety of treatments for primary hyperhidrosis is limited overall, and few firm conclusions can be drawn. However, there is moderate-quality evidence to support the use of BTX for axillary hyperhidrosis. A trial comparing BTX with iontophoresis for palmar hyperhidrosis is warranted.


Asunto(s)
Hiperhidrosis/terapia , Satisfacción del Paciente , Atención Secundaria de Salud/métodos , Toxinas Botulínicas Tipo A/administración & dosificación , Toxinas Botulínicas Tipo A/efectos adversos , Antagonistas Colinérgicos/administración & dosificación , Antagonistas Colinérgicos/efectos adversos , Legrado/efectos adversos , Legrado/métodos , Humanos , Hiperhidrosis/diagnóstico , Hiperhidrosis/patología , Iontoforesis/efectos adversos , Iontoforesis/métodos , Terapia por Luz de Baja Intensidad/efectos adversos , Terapia por Luz de Baja Intensidad/métodos , Ablación por Radiofrecuencia/efectos adversos , Ablación por Radiofrecuencia/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Índice de Severidad de la Enfermedad , Glándulas Sudoríparas/patología , Glándulas Sudoríparas/efectos de la radiación , Resultado del Tratamiento
18.
Spinal Cord ; 55(2): 114-125, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27995945

RESUMEN

STUDY DESIGN: Review study. OBJECTIVES: The identification of prognostic biomarkers of spinal cord injury (SCI) will help to assign SCI patients to the correct treatment and rehabilitation regimes. Further, the detection of biomarkers that predict permanent neurological outcome would aid in appropriate recruitment of patients into clinical trials. The objective of this review is to evaluate the current state-of-play in this developing field. SETTING: Studies from multiple countries were included. METHODS: We have completed a comprehensive review of studies that have investigated prognostic biomarkers in either the blood or cerebrospinal fluid (CSF) of animals and humans following SCI. RESULTS: Targeted and unbiased approaches have identified several prognostic biomarkers in CSF and blood. These proteins associate with cellular damage following SCI and include components from neurons, oligodendrocytes and reactive astrocytes, that is, neurofilament proteins, glial fibrillary acidic protein, Tau and S100 calcium-binding protein ß. Unbiased approaches have also identified microRNAs that are specific to SCI, as well as other cell damage-associated proteins. CONCLUSIONS: The discovery and validation of stable, specific, sensitive and reproducible biomarkers of SCI is a rapidly expanding field of research. So far, few studies have utilised unbiased approaches aimed at the discovery of biomarkers within the CSF or blood in this field; however, some targeted approaches have been successfully used. Several studies using various animal models and some with small human patient cohorts have begun to pinpoint biomarkers in the CSF and blood with putative prognostic value. An increased sample size will be required to validate these biomarkers in the heterogeneous clinical setting.


Asunto(s)
Mediadores de Inflamación/sangre , Mediadores de Inflamación/líquido cefalorraquídeo , Proteínas de Neurofilamentos/sangre , Proteínas de Neurofilamentos/líquido cefalorraquídeo , Traumatismos de la Médula Espinal/sangre , Traumatismos de la Médula Espinal/líquido cefalorraquídeo , Animales , Biomarcadores/sangre , Humanos , Pronóstico , Traumatismos de la Médula Espinal/diagnóstico
19.
Int Endod J ; 50 Suppl 2: e3-e8, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27977855

RESUMEN

AIM: To examine the effect of reduction in MTA particle size on dento-alveolar and osseous healing in dogs. METHODOLOGY: Root canals of 24 mandibular premolars in four 2-year-old beagles were prepared and filled with gutta-percha and sealer. Two to four weeks later, during periapical surgery, the root-end cavity preparations in these teeth were filled with either grey ProRoot MTA or modified (reduced particle sizes with faster setting time) MTA. The animals were sacrificed 4 months later. Degrees of inflammation, type of inflammatory cells, fibrous connective tissue adjacent to the root-end filling materials, cementum formation over the resected roots and root-end filling materials and bone healing were examined. Data were analysed using the McNemar test. RESULTS: No significant differences in healing of periapical tissues were found when comparing ProRoot MTA to a modified MTA containing reduced particle sizes. CONCLUSION: Reducing the particle sizes of MTA did not impact its biological properties.


Asunto(s)
Compuestos de Aluminio/farmacología , Compuestos de Calcio/farmacología , Óxidos/farmacología , Tejido Periapical/efectos de los fármacos , Materiales de Obturación del Conducto Radicular/farmacología , Tratamiento del Conducto Radicular , Silicatos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Diente Premolar/cirugía , Perros , Combinación de Medicamentos , Gutapercha/farmacología , Mandíbula , Tamaño de la Partícula
20.
Diabet Med ; 33(2): 231-4, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26484625

RESUMEN

AIMS: To identify the knowledge and management factors associated with glycaemic control among adults with Type 1 diabetes mellitus treated with insulin pump therapy. METHODS: A cross-sectional study of adults with Type 1 diabetes mellitus on insulin pump therapy for at least 12 months (n = 50, 18-70 years old) was undertaken between December 2013 and May 2014. A new questionnaire was developed to evaluate participants' knowledge and management related to insulin pump therapy, and were correlated with insulin pump data, HbA1c and frequency of hypoglycaemia. RESULTS: Participants who changed their insulin pump settings when indicated had significantly better glycaemic control than those who did not (P = 0.04). Multivariate logistic regression analysis found that better overall insulin pump therapy management was a significant predictor of better glycaemic control (odds ratio 4.45, 95% confidence interval 1.61-12.3; P = 0.004) after adjusting for potential confounders including age, gender, duration of diabetes and insulin pump therapy. However, overall insulin pump therapy knowledge was not a significant predictor of glycaemic control (P = 0.058). There was no significant association between frequency of hypoglycaemia and insulin pump therapy knowledge or management. CONCLUSIONS: We identified some key knowledge and management factors associated with glycaemic control in adults with Type 1 diabetes mellitus on insulin pump therapy using a newly designed questionnaire. The pilot study assessed the clinical utility of this evaluation tool, which may facilitate provision of targeted education to insulin pump therapy users to achieve optimal glycaemic control.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Conocimientos, Actitudes y Práctica en Salud , Hiperglucemia/prevención & control , Hipoglucemia/prevención & control , Sistemas de Infusión de Insulina , Cooperación del Paciente , Adulto , Australia , Terapia Combinada/efectos adversos , Estudios Transversales , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/dietoterapia , Diabetes Mellitus Tipo 1/terapia , Dieta para Diabéticos/efectos adversos , Ejercicio Físico , Hemoglobina Glucada/análisis , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Insulina/administración & dosificación , Insulina/efectos adversos , Insulina/uso terapéutico , Sistemas de Infusión de Insulina/efectos adversos , Resistencia a la Insulina , Educación del Paciente como Asunto , Satisfacción del Paciente , Proyectos Piloto , Estudios Prospectivos , Autoinforme
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