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2.
NPJ Microgravity ; 10(1): 42, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553471

RESUMEN

Twenty-four-hour rhythms in physiology and behaviour are shaped by circadian clocks, environmental rhythms, and feedback of behavioural rhythms onto physiology. In space, 24 h signals such as those associated with the light-dark cycle and changes in posture, are weaker, potentially reducing the robustness of rhythms. Head down tilt (HDT) bed rest is commonly used to simulate effects of microgravity but how HDT affects rhythms in physiology has not been extensively investigated. Here we report effects of -6° HDT during a 90-day protocol on 24 h rhythmicity in 20 men. During HDT, amplitude of light, motor activity, and wrist-temperature rhythms were reduced, evening melatonin was elevated, while cortisol was not affected during HDT, but was higher in the morning during recovery when compared to last session of HDT. During recovery from HDT, time in Slow-Wave Sleep increased. EEG activity in alpha and beta frequencies increased during NREM and REM sleep. These results highlight the profound effects of head-down-tilt-bed-rest on 24 h rhythmicity.

3.
J Diet Suppl ; 21(2): 167-181, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37127913

RESUMEN

There is growing interest of ergogenic aids that deliver supplemental oxygen during exercise and recovery, however, breathing supplemental oxygen via specialist facemasks is often not feasible. Therefore, this study investigated the effect of an oxygen-nanobubble beverage during submaximal and repeated sprint cycling. In a double-blind, randomized, placebo-controlled study, 10 male cyclists (peak aerobic capacity, 56.9 ± 6.1 mL·kg-1·min-1; maximal aerobic power, 385 ± 25 W) completed submaximal or maximal exercise after consuming an oxygen-nanobubble (O2) or placebo (PLA) beverage. Submaximal trials comprised 30-min of steady-state cycling at 60% peak aerobic capacity and 16.1-km time-trial (TT). Maximal trials involved 4 × 30 s Wingate tests interspersed by 4-min recovery. Time-to-completion during the 16.1-km TT was 2.4% faster after O2 compared with PLA (95% CI = 0.7-4.0%, p = 0.010, d = 0.41). Average power for the 16.1-km TT was 4.1% higher for O2 vs. PLA (95% CI = 2.1-7.3%, p = 0.006, d = 0.28). Average peak power during the repeated Wingate tests increased by 7.1% for O2 compared with PLA (p = 0.002, d = 0.58). An oxygen-nanobubble beverage improves performance during submaximal and repeated sprint cycling, therefore may provide a practical and effective ergogenic aid for competitive cyclists.


Asunto(s)
Rendimiento Atlético , Sustancias para Mejorar el Rendimiento , Masculino , Humanos , Proyectos Piloto , Método Doble Ciego , Bebidas , Ciclismo , Oxígeno , Poliésteres , Consumo de Oxígeno , Estudios Cruzados
4.
Clin Med (Lond) ; 23(6): 563-570, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-38065610

RESUMEN

INTRODUCTION: The burden of chronic viral hepatitis (CVH) in the UK Nepali population is unknown. We aimed to determine knowledge of liver disease (LD) and prevalence of CVH in this community. METHODS: This was a mixed method (qualitative and quantitative) study guided by a multidisciplinary stakeholder group. Focus groups (FG) led by Nepali community leaders explored LD knowledge. Thereafter, a prospective community-based cohort study utilising dried-blood spot testing was conducted. Thematic analysis explored FG data with categorical data analysed with Excel and R Studio. RESULTS: FG data showed a lack of LD knowledge, with conflict between the roles of traditional and modern practices; 1,005 participants (525 male, 480 female) were tested for CVH, with a mean age of 63 years (range:19-86). Rates of CVH infection were low: 0.3% had current hepatitis B, with no active hepatitis C. DISCUSSION: Key drivers for enthusiastic participation were development of peer support networks and advisory groups to disseminate information, including hepatitis B vaccine recommendations.


Asunto(s)
Hepatitis B , Migrantes , Humanos , Masculino , Femenino , Persona de Mediana Edad , Prevalencia , Estudios de Cohortes , Estudios Prospectivos , Hepatitis B/epidemiología , Reino Unido/epidemiología
5.
BMJ Open ; 13(8): e068387, 2023 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-37620271

RESUMEN

OBJECTIVE: Hypokalaemia and hyperkalaemia ('dyskalaemia') are commonly seen in patients requiring emergency hospital admission. The adverse effect of dyskalaemia on mortality is well described but there are few data for the effect on hospital length of stay. We sought to determine the association of serum potassium concentration with in-hospital length of stay. DESIGN: Systematic review and meta-analysis. DATA SOURCES: A structured search of MEDLINE, PubMed and SCOPUS databases to 19 March 2021. ELIGIBILITY CRITERIA: Observational cohort studies defining exposure of interest as serum potassium levels (at admission or within the first 72 hours) and with outcome of interest as length of hospital stay. Studies had to provide estimates of length of stay as a comparison between normokalaemia and defined ranges of hyperkalaemia or hypokalaemia. DATA EXTRACTION AND SYNTHESIS: We identified 39 articles published to March 2021 that met the inclusion and exclusion criteria. Study selection, data extraction and quality assessment were carried out by two reviewers working independently and in duplicate, to assessed eligibility and risk of bias, and extract data from eligible studies. Random effects models were used to pool estimates across the included studies. Meta-analyses were performed using Cochrane-RevMan. RESULTS: Five studies were included in the meta-analysis. Compared with the reference group (3.5-5.0 mmol/L), the pooled raw differences of medians were 4.45 (95% CI 2.71 to 6.91), 1.99 (95% CI 0.03 to 3.94), 0.98 (95% CI 0.91 to 1.05), 1.51 (95% CI 1.03 to 2.0), 1 (95% CI 0.75 to 1.25) and 2.76 (95% CI 1.24 to 4.29) for patients with potassium levels of <2.5, 2.5 to <3.0, 3.0 to <3.5, <5 to 5.5, <5.5 to 6 and >6.0 mmol/L, respectively. CONCLUSION: Hospital length of stay follows a U-shaped distribution, with duration of admission being twofold greater at the extremes of the potassium range.


Asunto(s)
Hiperpotasemia , Hipopotasemia , Humanos , Tiempo de Internación , Hospitalización , Potasio
6.
Cancer Med ; 12(8): 9999-10007, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36934449

RESUMEN

BACKGROUND: Multidisciplinary team meetings (MDTMs), where treatment recommendations are discussed and agreed, are fundamental to effective cancer care. The increasing volume and complexity of caseloads has led to the need to transform MDTM pathways to improve efficiency and allow sufficient time for discussion of complex cases. Understanding of current functioning and inefficiencies is required to inform such transformation. METHODS: A mixed-methods observational study of all lung cancer MDTMs in one UK cancer network over 12 weeks (n = 8 MDTs, 96 MDT meetings). Data were collected on meeting attendance and on each discussed case using a validated MDT tool. Semi-structured interviews were conducted with a range of MDT members and cancer service managers to gain understanding of perceived influences on the efficiency of MDTMs. RESULTS: In total, 1671 case discussions were observed. Models of MDT working, including referral and diagnostic pathway management, varied within the network. Attendance was quorate in only 21% of the observed MDTMs, most often lacking palliative care specialists. Over a third (37%) of observed cases were repeat discussions pre-diagnosis. Treatment recommendations were agreed in 48% of case discussions but deferred for a quarter (24%) of discussed cases, most commonly due to awaiting results. Information about patients' fitness for treatment and/or performance status score was available for 60% of cases discussed overall (30%-75% by MDT). Interviews (n = 56) identified addressing clinical and administrative workforce shortages, less reliance on the MDTM for pre-diagnostic decision-making and better availability of key clinical information about patients discussed in the MDTM as factors critical to improved MDT function. CONCLUSIONS: Inefficiencies were prevalent in all MDTMs; improvements would require an individualised approach due to the variation in ways of working. Local, regional and national support is needed for lung MDTs to develop their diagnostic workforce and facilities, and clinical and administrative resource.


Asunto(s)
Neoplasias Pulmonares , Neoplasias , Humanos , Grupo de Atención al Paciente , Neoplasias/terapia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Toma de Decisiones , Pulmón
7.
Cancers (Basel) ; 15(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36672452

RESUMEN

Survival prediction is integral to oncology and palliative care, yet robust prognostic models remain elusive. We assessed the feasibility of combining actigraphy, sleep diary data, and routine clinical parameters to prognosticate. Fifty adult outpatients with advanced cancer and estimated prognosis of <1 year were recruited. Patients were required to wear an Actiwatch® (wrist actigraph) for 8 days, and complete a sleep diary. Univariate and regularised multivariate regression methods were used to identify predictors from 66 variables and construct predictive models of survival. A total of 49 patients completed the study, and 34 patients died within 1 year. Forty-two patients had disrupted rest-activity rhythms (dichotomy index (I < O ≤ 97.5%) but I < O did not have prognostic value in univariate analyses. The Lasso regularised derived algorithm was optimal and able to differentiate participants with shorter/longer survival (log rank p < 0.0001). Predictors associated with increased survival time were: time of awakening sleep efficiency, subjective sleep quality, clinician's estimate of survival and global health status score, and haemoglobin. A shorter survival time was associated with self-reported sleep disturbance, neutrophil count, serum urea, creatinine, and C-reactive protein. Applying machine learning to actigraphy and sleep data combined with routine clinical data is a promising approach for the development of prognostic tools.

8.
J Clin Med ; 11(14)2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35887701

RESUMEN

Muscle wasting is implicated in the pathogenesis of intensive care unit acquired weakness (ICU-AW), affecting 40% of patients and causing long-term physical disability. A repetitive vascular occlusion stimulus (RVOS) limits muscle atrophy in healthy and orthopaedic subjects, thus, we explored its application to ICU patients. Adult multi-organ failure patients received standard care +/- twice daily RVOS {4 cycles of 5 min tourniquet inflation to 50 mmHg supra-systolic blood pressure, and 5 min complete deflation} for 10 days. Serious adverse events (SAEs), tolerability, feasibility, acceptability, and exploratory outcomes of the rectus femoris cross-sectional area (RFCSA), echogenicity, clinical outcomes, and blood biomarkers were assessed. Only 12 of the intended 32 participants were recruited. RVOS sessions (76.1%) were delivered to five participants and two could not tolerate it. No SAEs occurred; 75% of participants and 82% of clinical staff strongly agreed or agreed that RVOS is an acceptable treatment. RFCSA fell significantly and echogenicity increased in controls (n = 5) and intervention subjects (n = 4). The intervention group was associated with less frequent acute kidney injury (AKI), a greater decrease in the total sequential organ failure assessment score (SOFA) score, and increased insulin-like growth factor-1 (IGF-1), and reduced syndecan-1, interleukin-4 (IL-4) and Tumor necrosis factor receptor type II (TNF-RII) levels. RVOS application appears safe and acceptable, but protocol modifications are required to improve tolerability and recruitment. There were signals of possible clinical benefit relating to RVOS application.

9.
Nutr Health ; : 2601060221106624, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35726202

RESUMEN

BACKGROUND: The benefits of a healthy lifestyle in reducing risk of cancer and chronic disease are well-documented. Many individuals who have had head and neck cancer (HNC) report complex social situations with a history of poor dietary habits, smoking and alcohol abuse. Survivorship can be a strong motivator to make positive lifestyle changes, reducing risk of cancer recurrence and ill-health. Research investigating whether HNC survivors adopt healthy lifestyle recommendations is lacking. AIM: To explore the health-related practices of post-treatment HNC patients, seeking to identify barriers and motivators to following recommended health guidelines. METHODS: Tape-recorded interviews were conducted with 20 HNC survivors, and comparisons made to Department of Health recommendations. RESULTS: 80% of participants made lifestyle changes following HNC treatment. The most prevalent changes were to diet and alcohol intake. Key motivators were reducing cancer risk and ill-health; barriers included lack of motivation, support and misinformation. Treatment side-effects presented both motivators and barriers. There was widespread recognition of the "5 a day" message, and harm caused by smoking. Other public health recommendations were less well-known; 98% were unaware of current alcohol guidelines, physical activity was overestimated, and only one participant took vitamin D. CONCLUSION: In this study HNC survivors were highly motivated to make healthy lifestyle changes. Further work is required to increase awareness of Government guidelines, as health messages are not always reaching the public or are misinterpreted.

10.
Diabetes Care ; 45(6): 1408-1415, 2022 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-35312749

RESUMEN

OBJECTIVE: To investigate the mechanism for increased ketogenesis following treatment with the SGLT2 inhibitor dapagliflozin in people with type 2 diabetes. RESEARCH DESIGN AND METHODS: The design was a double-blind, placebo-controlled, crossover study with a 4-week washout period. Participants received dapagliflozin or placebo in random order for 4 weeks. After each treatment, they ingested 30 mL of olive oil containing [U-13C]palmitate to measure ketogenesis, with blood sampling for 480 min. Stable isotopes of glucose and glycerol were infused to measure glucose flux and lipolysis, respectively, at 450-480 min. RESULTS: Glucose excretion rate was higher and peripheral glucose uptake lower with dapagliflozin than placebo. Plasma ß-hydroxybutyrate (BOHB) concentrations and [13C2]BOHB concentrations were higher and glucose concentrations lower with dapagliflozin than placebo. Nonesterified fatty acids (NEFAs) were higher with dapagliflozin at 300 and 420 min, but lipolysis at 450-480 min was not different. Triacylglycerol at all time points and endogenous glucose production rate at 450-480 min were not different between treatments. CONCLUSIONS: The increase in ketone enrichment from the ingested palmitic acid tracer suggests that meal-derived fatty acids contribute to the increase in ketones during treatment with dapagliflozin. The increase in BOHB concentration with dapagliflozin occurred with only minimal changes in plasma NEFA concentration and no change in lipolysis. This finding suggests a metabolic switch to increase ketogenesis within the liver.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Compuestos de Bencidrilo , Glucemia/metabolismo , Estudios Cruzados , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Método Doble Ciego , Ácidos Grasos , Ácidos Grasos no Esterificados , Glucosa/metabolismo , Glucósidos , Humanos , Hipoglucemiantes/uso terapéutico , Cetonas , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico
11.
Neuropsychopharmacology ; 47(3): 719-727, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34628482

RESUMEN

The effects of orexinergic peptides are diverse and are mediated by orexin-1 and orexin-2 receptors. Antagonists that target both receptors have been shown to promote sleep initiation and maintenance. Here, we investigated the role of the orexin-2 receptor in sleep regulation in a randomised, double-blind, placebo-controlled, three-period crossover clinical trial using two doses (20 and 50 mg) of a highly selective orexin-2 receptor antagonist (2-SORA) (JNJ-48816274). We used a phase advance model of sleep disruption where sleep initiation is scheduled in the circadian wake maintenance zone. We assessed objective and subjective sleep parameters, pharmacokinetic profiles and residual effects on cognitive performance in 18 healthy male participants without sleep disorders. The phase advance model alone (placebo condition) resulted in disruption of sleep at the beginning of the sleep period compared to baseline sleep (scheduled at habitual time). Compared to placebo, both doses of JNJ-48816274 significantly increased total sleep time, REM sleep duration and sleep efficiency, and reduced latency to persistent sleep, sleep onset latency, and REM latency. All night EEG spectral power density for both NREM and REM sleep were unaffected by either dose. Participants reported significantly better quality of sleep and feeling more refreshed upon awakening following JNJ-48816274 compared to placebo. No significant residual effects on objective performance measures were observed and the compound was well tolerated. In conclusion, the selective orexin-2 receptor antagonist JNJ-48816274 rapidly induced sleep when sleep was scheduled earlier in the circadian cycle and improved self-reported sleep quality without impact on waking performance.


Asunto(s)
Antagonistas de los Receptores de Orexina , Trastornos del Inicio y del Mantenimiento del Sueño , Método Doble Ciego , Humanos , Masculino , Antagonistas de los Receptores de Orexina/farmacología , Receptores de Orexina , Orexinas/farmacología , Polisomnografía , Sueño/fisiología , Trastornos del Inicio y del Mantenimiento del Sueño/inducido químicamente
12.
Eur J Clin Nutr ; 76(4): 516-526, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34282293

RESUMEN

BACKGROUND/OBJECTIVES: Vitamin D deficiency remains a global public health issue, particularly in minority ethnic groups. This review investigates the vitamin D status (as measured by 25(OH)D and dietary intake) of the African-Caribbean population globally. SUBJECTS/METHODS: A systematic review was conducted by searching key databases (PUBMED, Web of Science, Scopus) from inception until October 2019. Search terms included 'Vitamin D status' and 'African-Caribbean'. A random effects and fixed effects meta-analysis was performed by combining means and standard error of the mean. RESULT: The search yielded 19 papers that included n = 5670 African-Caribbean participants from six countries. A meta-analysis found this population to have sufficient (>50 nmol/L) 25(OH)D levels at 67.8 nmol/L, 95% CI (57.9, 7.6) but poor dietary intake of vitamin D at only 3.0 µg/day, 95% CI (1.67,4.31). For those living at low latitudes 'insufficient' (as defined by study authors) 25(OH)D levels were found only in participants with type 2 diabetes and in those undergoing haemodialysis. Suboptimal dietary vitamin D intake (according to the UK recommended nutrient intake of 10 µg/day) was reported in all studies at high latitudes. Studies at lower latitudes, with lower recommended dietary intakes (Caribbean recommended dietary intake: 2.5 µg/day) found 'sufficient' intake in two out of three studies. CONCLUSIONS: 25(OH)D sufficiency was found in African-Caribbean populations at lower latitudes. However, at higher latitudes, 25(OH)D deficiency and low dietary vitamin D intake was prevalent.


Asunto(s)
Diabetes Mellitus Tipo 2 , Deficiencia de Vitamina D , Suplementos Dietéticos , Humanos , Estaciones del Año , Vitamina D , Deficiencia de Vitamina D/epidemiología , Vitaminas
13.
Curr Oncol ; 28(3): 2260-2269, 2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-34207352

RESUMEN

In the UK, Trifluridine-tipiracil (Lonsurf) is used to treat metastatic colorectal cancer in the third-line setting, after prior exposure to fluoropyrimidine-based regimes. Current data on the real-world use of Lonsurf lack long-term follow-up data. A retrospective evaluation of patients receiving Lonsurf at our Cancer Centre in 2016-2017 was performed, all with a minimum of two-year follow-up. Fifty-six patients were included in the review. The median number of cycles of Lonsurf administered was 3. Median follow-up was 6.0 months, with all patients deceased at the time of analysis. Median progression-free survival (PFS) was 3.2 months, and overall survival (OS) was 5.8 months. The median interval from Lonsurf discontinuation to death was two months, but seven patients received further systemic treatment and median OS gained was 12 months. Lonsurf offered a slightly better PFS but inferior OS to that of the RECOURSE trial, with PFS similar to real-world data previously presented. Interestingly, 12.5% had a PFS > 9 months, and this cohort had primarily left-sided and RAS wild-type disease. A subset received further systemic treatment on Lonsurf discontinuation with good additional OS benefit. Lonsurf may alter the course of disease for a subset of patients, and further treatment on progression can be considered in carefully selected patients.


Asunto(s)
Neoplasias Colorrectales , Trifluridina , Neoplasias Colorrectales/tratamiento farmacológico , Combinación de Medicamentos , Humanos , Pirrolidinas , Estudios Retrospectivos , Timina , Reino Unido
14.
J Nutr ; 151(10): 3137-3150, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34255034

RESUMEN

BACKGROUND: Vitamin D concentrations are a function of sunlight exposure and dietary intake. However, current dietary vitamin D recommendations do not consider differences in country-specific sunlight availability or spontaneous individual exposure. OBJECTIVES: We aimed to investigate the effects of vitamin D supplementation and sunlight exposure on vitamin D concentrations in Brazilian women living in high compared with low latitudes. METHODS: In 2 parallel, double-blind, randomized placebo-controlled trials, Brazilian women living in England (51°N) composed "without ultraviolet B (UVB) exposure" groups and those living in Brazil (16°S) composed the "with UVB exposure" groups (mean age, 31.39 ± 8.7 years). Participants received 15 µg cholecalciferol or placebo daily for 12 weeks during wintertime. Serum 25-hydroxyvitamin D [25(OH)D] concentrations, the primary outcome, were assessed by HPLC-MS/MS, vitamin D intakes were assessed by 4-day diet diaries, and sunlight exposure was assessed by UVB dosimeters. The effects of supplementation and UVB exposure were tested by the intention to treat with a linear mixed model. RESULTS: The 25(OH)D concentrations increased in both supplemented groups [from 75.1 ± 22.0 to 84.8 ± 21.0 nmol/L (P = 0.004) in the group with UVB exposure; from 38.1 ± 15.9 to 55.1 ± 12.2 nmol/L (P < 0.001) in the group without UVB exposure], with no significant changes in either placebo group. Concentrations in both supplemented groups were higher than those in the placebo group without UVB exposure (P = 0.0002 in the group with UVB exposure; P = 0.0035 in the group without UVB exposure). Postintervention 25(OH)D concentrations were significantly affected by serum 25(OH)D concentrations at baseline (P < 0.0001) and by intervention (placebo or supplement; P > 0.0001), with a large effect size (Cohen's D = 0.768), but were not affected by UVB exposure (with or without; P = 0.1386), nor by the interaction between the intervention (placebo or supplement) and UVB exposure (with or without; P = 0.9845). CONCLUSIONS: Moderate supplementation of 15 ug/d cholecalciferol, in accordance with current recommendations, supports an adequate vitamin D status in adult women, irrespective of latitude, and might concomitantly prevent an increase in parathyroid hormone. The Interaction Between Vitamin D Supplementation and Sunlight Exposure in Women Living in Opposite Latitudes (D-SOL) study was registered at clinicaltrials.gov as NCT03318029.


Asunto(s)
Luz Solar , Deficiencia de Vitamina D , Adulto , Colecalciferol , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Estaciones del Año , Espectrometría de Masas en Tándem , Vitamina D , Deficiencia de Vitamina D/prevención & control , Adulto Joven
15.
EFORT Open Rev ; 6(5): 331-342, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34150327

RESUMEN

The literature was reviewed to establish the levels of stem subsidence for both double and triple-tapered implants in order to determine whether there were any differences in subsidence levels with regard to the methods of measurement, the magnitude and rate of subsidence and clinical outcomes.All studies reporting subsidence of polished taper-slip stems were identified. Patient demographics, implant design, radiological findings, details of surgical technique, methods of measurement and levels of subsidence were collected to investigate which factors were related to increased subsidence.Following application of inclusion and exclusion criteria, 28 papers of relevance were identified. The studies initially recruited 3090 hips with 2099 being available for radiological analysis at final follow-up. Patient age averaged 68 years (42-70), 60.4% were female and the average body mass index (BMI) was 27.4 kg/m2 (24.1-29.2).Mean subsidence at one, two, five and 10 years was 0.97 mm, 1.07 mm, 1.47 mm and 1.61 mm respectively. Although double-tapered stems subsided more than triple-tapered stems at all time points this was not statistically significant (p > 0.05), nor was the method of measurement used (p > 0.05).We report the levels of subsidence at which clinical outcomes and survivorship remain excellent, but based on the literature it was not possible to determine a threshold of subsidence beyond which failure was more likely.There were relatively few studies of triple-tapered stems, but given that there were no statistically significant differences, the levels presented in this review can be applied to both double and triple-tapered designs. Cite this article: EFORT Open Rev 2021;6:331-342. DOI: 10.1302/2058-5241.6.200086.

16.
PLoS One ; 16(4): e0249671, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33798240

RESUMEN

The potential ergogenic effects of vitamin D (vitD) in high performing athletes has received considerable attention in the literature and media. However, little is known about non-supplemented university athletes and students residing at a higher latitude. This study aimed to investigate the effects of vitD (biochemical status and dietary intake) on exercise performance in UK university athletes and sedentary students. A total of 34 athletes and 16 sedentary controls were studied during the spring and summer months. Serum vitD status and sunlight exposure were assessed using LC-MS/MS and dosimetry, respectively. Muscular strength of the upper and lower body was assessed using handgrip and knee extensor dynamometry (KE). Countermovement jump (CMJ) and aerobic fitness were measured using an Optojump and VO2max test, respectively. Statistical analysis was performed using paired/ independent t-tests, ANCOVA and Pearson/ Spearman correlations, depending on normality. VitD status increased significantly over the seasons, with athletes measuring higher status both in spring (51.7±20.5 vs. 37.2±18.9 nmol/L, p = 0.03) and summer (66.7±15.8 vs 55.6±18.8 nmol/L, p = 0.04) when compared to controls, respectively. Notably, 22% of the subjects recruited were vitD deficient during the spring term only (<25nmol/L, n 9). Subjects with 'insufficient' vitD status (<50nmol/L) elicited significantly lower CMJ when contrasted to the vitD 'sufficient' (>50nmol/l) group (p = 0.055) and a lower VO2 max (p = 0.05) in the spring and summer term (p = 0.05 and p = 0.01, respectively). However, an ANCOVA test showed no significant difference detected for either CMJ or VO2max following adjustments for co-variates. In conclusion, we provide novel information on the vitD status, dietary intake, physical fitness and sunlight exposure of UK young adults across two separate seasons, for which there is limited data at present.


Asunto(s)
Ejercicio Físico/fisiología , Vitamina D/metabolismo , Adulto , Atletas , Cromatografía Liquida , Suplementos Dietéticos , Femenino , Fuerza de la Mano/fisiología , Humanos , Masculino , Fuerza Muscular/fisiología , Estado Nutricional , Estaciones del Año , Conducta Sedentaria , Luz Solar , Espectrometría de Masas en Tándem , Reino Unido , Universidades , Vitamina D/sangre , Vitamina D/fisiología , Deficiencia de Vitamina D/sangre
18.
Am J Clin Nutr ; 112(2): 389-412, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32320029

RESUMEN

BACKGROUND: Mild-to-moderate iodine deficiency, particularly in pregnancy, is prevalent; this is of concern because observational studies have shown negative associations with child neurodevelopment. Although neither the benefits nor the safety of iodine supplementation in pregnancy in areas of mild-to-moderate deficiency are well researched, such supplementation is increasingly being recommended by health authorities in a number of countries. OBJECTIVES: By reviewing the most recent published data on the effects of iodine supplementation in mildly-to-moderately deficient pregnant women on maternal and infant thyroid function and child cognition, we aimed to determine whether the evidence was sufficient to support recommendations in these areas. METHODS: A systematic review of randomized controlled trials (RCTs), non-RCT interventions, and observational studies was conducted. To identify relevant articles, we searched the PubMed and Embase databases. We defined mild-to-moderate iodine deficiency as a baseline median urinary iodine concentration (UIC) of 50-149 µg/L. Eligible studies were included in meta-analyses. RESULTS: In total, 37 publications were included-10 RCTs, 4 non-RCT interventions, and 23 observational studies. Most studies showed no effect of iodine supplementation on maternal or infant thyroid-stimulating hormone and free thyroxine. Most RCTs found that supplementation reduced maternal thyroglobulin and in 3 RCTs, it prevented or diminished the increase in maternal thyroid volume during pregnancy. Three RCTs addressed child neurodevelopment; only 1 was adequately powered. Meta-analyses of 2 RCTs showed no effect on child cognitive [mean difference (MD): -0.18; 95% CI: -1.22, 0.87], language (MD: 1.28; 95% CI: -0.28, 2.83), or motor scores (MD: 0.28; 95% CI: -1.10, 1.66). CONCLUSIONS: There is insufficient good-quality evidence to support current recommendations for iodine supplementation in pregnancy in areas of mild-to-moderate deficiency. Well-designed RCTs, with child cognitive outcomes, are needed in pregnant women who are moderately deficient (median UIC < 100 µg/L). Maternal intrathyroidal iodine stores should be considered in future trials by including appropriate measures of preconceptional iodine intake.This review was registered at www.crd.york.ac.uk/prospero as CRD42018100277.


Asunto(s)
Desarrollo Infantil/efectos de los fármacos , Yodo/administración & dosificación , Trastornos del Neurodesarrollo/prevención & control , Complicaciones del Embarazo/tratamiento farmacológico , Adulto , Niño , Suplementos Dietéticos , Femenino , Humanos , Lactante , Yodo/deficiencia , Trastornos del Neurodesarrollo/metabolismo , Embarazo , Pruebas de Función de la Tiroides , Hormonas Tiroideas/metabolismo
19.
Trials ; 20(1): 456, 2019 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-31340849

RESUMEN

BACKGROUND: Forty per cent of critically ill patients are affected by intensive care unit-acquired weakness (ICU-AW), to which skeletal muscle wasting makes a substantial contribution. This can impair outcomes in hospital, and can cause long-term physical disability after hospital discharge. No effective mitigating strategies have yet been identified. Application of a repetitive vascular occlusion stimulus (RVOS) a limb pressure cuff inducing brief repeated cycles of ischaemia and reperfusion, can limit disuse muscle atrophy in both healthy controls and bed-bound patients recovering from knee surgery. We wish to determine whether RVOS might be effective in mitigating against muscle wasting in the ICU. Given that RVOS can also improve vascular function in healthy controls, we also wish to assess such effects in the critically ill. We here describe a pilot study to assess whether RVOS application is safe, tolerable, feasible and acceptable for ICU patients. METHODS: This is a randomised interventional feasibility trial. Thirty-two ventilated adult ICU patients with multiorgan failure will be recruited within 48 h of admission and randomised to either the intervention arm or the control arm. Intervention participants will receive RVOS twice daily (except only once on day 1) for up to 10 days or until ICU discharge. Serious adverse events and tolerability (pain score) will be recorded; feasibility of trial procedures will be assessed against pre-specified criteria and acceptability by semi-structured interview. Together with vascular function, muscle mass and quality will be assessed using ultrasound and measures of physical function at baseline, on days 6 and 11 of study enrolment, and at ICU and hospital discharge. Blood and urine biomarkers of muscle metabolism, vascular function, inflammation and DNA damage/repair mechanism will also be analysed. The Health questionnaire will be completed 3 months after hospital discharge. DISCUSSION: If this study demonstrates feasibility, the derived data will be used to inform the design (and sample size) of an appropriately-powered prospective trial to clarify whether RVOS can help preserve muscle mass/improve vascular function in critically ill patients. TRIAL REGISTRATION: ISRCTN Registry, ISRCTN44340629. Registered on 26 October 2017.


Asunto(s)
Debilidad Muscular/prevención & control , Músculo Esquelético/irrigación sanguínea , Atrofia Muscular/prevención & control , Oclusión Terapéutica/métodos , Enfermedad Crítica , Inglaterra , Estudios de Factibilidad , Humanos , Estudios Multicéntricos como Asunto , Debilidad Muscular/diagnóstico , Debilidad Muscular/fisiopatología , Atrofia Muscular/diagnóstico , Atrofia Muscular/fisiopatología , Proyectos Piloto , Ensayos Clínicos Controlados Aleatorios como Asunto , Flujo Sanguíneo Regional , Oclusión Terapéutica/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
20.
J Clin Endocrinol Metab ; 104(2): 359-368, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30215735

RESUMEN

Context: Glucagon-like peptide-1 (GLP-1) agonists control postprandial glucose and lipid excursion in type 2 diabetes; however, the mechanisms are unclear. Objective: To determine the mechanisms of postprandial lipid and glucose control with lixisenatide (GLP-1 analog) in type 2 diabetes. Design: Randomized, double-blind, cross-over study. Setting: Centre for Diabetes, Endocrinology, and Research, Royal Surrey County Hospital, Guildford, United Kingdom. Patients: Eight obese men with type 2 diabetes [age, 57.3 ± 1.9 years; body mass index, 30.3 ± 1.0 kg/m2; glycosylated hemoglobin, 66.5 ± 2.6 mmol/mol (8.2% ± 0.3%)]. Interventions: Two metabolic studies, 4 weeks after lixisenatide or placebo, with cross-over and repetition of studies. Main Outcome Measures: Study one: very-low-density lipoprotein (VLDL) and chylomicron (CM) triacylglycerol (TAG) kinetics were measured with an IV bolus of [2H5]glycerol in a 12-hour study, with hourly feeding. Oral [13C]triolein, in a single meal, labeled enterally derived TAG. Study two: glucose kinetics were measured with [U-13C]glucose in a mixed-meal (plus acetaminophen to measure gastric emptying) and variable IV [6,6-2H2]glucose infusion. Results: Study one: CM-TAG (but not VLDL-TAG) pool-size was lower with lixisenatide (P = 0.046). Lixisenatide reduced CM [13C]oleate area under the curve (AUC)60-480min concentration (P = 0.048) and increased CM-TAG clearance, with no effect on CM-TAG production rate. Study two: postprandial glucose and insulin AUC0-240min were reduced with lixisenatide (P = 0.0051; P < 0.05). Total glucose production (P = 0.015), rate of glucose appearance from the meal (P = 0.0098), and acetaminophen AUC0-360min (P = 0.006) were lower with lixisenatide than with placebo. Conclusions: Lixisenatide reduced [13C]oleate concentrations, derived from a single meal in CM-TAG and glucose rate of appearance from the meal through delayed gastric emptying. However, day-long CM production, measured with repeated meal feeding, was not reduced by lixisenatide and decreased CM-TAG concentration resulted from increased CM-TAG clearance.


Asunto(s)
Quilomicrones/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/farmacología , Péptidos/farmacología , Triglicéridos/sangre , Glucemia/efectos de los fármacos , Quilomicrones/metabolismo , Estudios Cruzados , Diabetes Mellitus Tipo 2/sangre , Método Doble Ciego , Vaciamiento Gástrico/efectos de los fármacos , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Humanos , Hipoglucemiantes/uso terapéutico , Masculino , Tasa de Depuración Metabólica/efectos de los fármacos , Persona de Mediana Edad , Péptidos/uso terapéutico , Periodo Posprandial/efectos de los fármacos , Resultado del Tratamiento , Triglicéridos/metabolismo
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