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1.
Phys Rev Lett ; 128(21): 212503, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35687456

RESUMO

An unexplained >4σ discrepancy persists between "beam" and "bottle" measurements of the neutron lifetime. A new model proposed that conversions of neutrons n into mirror neutrons n^{'}, part of a dark mirror sector, can increase the apparent neutron lifetime by 1% via a small mass splitting Δm between n and n^{'} inside the 4.6 T magnetic field of the National Institute of Standards and Technology Beam Lifetime experiment. A search for neutron conversions in a 6.6 T magnetic field was performed at the Spallation Neutron Source which excludes this explanation for the neutron lifetime discrepancy.

2.
J Synchrotron Radiat ; 28(Pt 3): 688-706, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33949979

RESUMO

The high-precision X-ray diffraction setup for work with diamond anvil cells (DACs) in interaction chamber 2 (IC2) of the High Energy Density instrument of the European X-ray Free-Electron Laser is described. This includes beamline optics, sample positioning and detector systems located in the multipurpose vacuum chamber. Concepts for pump-probe X-ray diffraction experiments in the DAC are described and their implementation demonstrated during the First User Community Assisted Commissioning experiment. X-ray heating and diffraction of Bi under pressure, obtained using 20 fs X-ray pulses at 17.8 keV and 2.2 MHz repetition, is illustrated through splitting of diffraction peaks, and interpreted employing finite element modeling of the sample chamber in the DAC.

3.
BMC Psychiatry ; 20(1): 458, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32962684

RESUMO

BACKGROUND: Promoting well-being and preventing poor mental health in young people is a major global priority. Building emotional competence (EC) skills via a mobile app may be an effective, scalable and acceptable way to do this. However, few large-scale controlled trials have examined the efficacy of mobile apps in promoting mental health in young people; none have tailored the app to individual profiles. METHOD/DESIGN: The Emotional Competence for Well-Being in Young Adults cohort multiple randomised controlled trial (cmRCT) involves a longitudinal prospective cohort to examine well-being, mental health and EC in 16-22 year olds across 12 months. Within the cohort, eligible participants are entered to either the PREVENT trial (if selected EC scores at baseline within worst-performing quartile) or to the PROMOTE trial (if selected EC scores not within worst-performing quartile). In both trials, participants are randomised (i) to continue with usual practice, repeated assessments and a self-monitoring app; (ii) to additionally receive generic cognitive-behavioural therapy self-help in app; (iii) to additionally receive personalised EC self-help in app. In total, 2142 participants aged 16 to 22 years, with no current or past history of major depression, bipolar disorder or psychosis will be recruited across UK, Germany, Spain, and Belgium. Assessments take place at baseline (pre-randomisation), 1, 3 and 12 months post-randomisation. Primary endpoint and outcome for PREVENT is level of depression symptoms on the Patient Health Questionnaire-9 at 3 months; primary endpoint and outcome for PROMOTE is emotional well-being assessed on the Warwick-Edinburgh Mental Wellbeing Scale at 3 months. Depressive symptoms, anxiety, well-being, health-related quality of life, functioning and cost-effectiveness are secondary outcomes. Compliance, adverse events and potentially mediating variables will be carefully monitored. CONCLUSIONS: The trial aims to provide a better understanding of the causal role of learning EC skills using interventions delivered via mobile phone apps with respect to promoting well-being and preventing poor mental health in young people. This knowledge will be used to develop and disseminate innovative evidence-based, feasible, and effective Mobile-health public health strategies for preventing poor mental health and promoting well-being. TRIAL REGISTRATION: ClinicalTrials.gov ( www.clinicaltrials.org ). Number of identification: NCT04148508 November 2019.


Assuntos
Telefone Celular , Aplicativos Móveis , Adolescente , Adulto , Bélgica , Alemanha , Humanos , Saúde Mental , Estudos Prospectivos , Qualidade de Vida , Espanha , Adulto Jovem
4.
Acta Psychiatr Scand ; 139(5): 443-453, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30865288

RESUMO

OBJECTIVE: To (i) validate patient-evaluated mixed symptoms and irritability measured using smartphones against clinical evaluations; (ii) investigate associations between mixed symptoms and irritability with stress, quality of life and functioning, respectively, in patients with bipolar disorder. METHODS: A total of 84 patients with bipolar disorder used a smartphone-based system for daily evaluation of mixed symptoms and irritability for nine months. Clinically evaluated symptoms, stress, quality of life and clinically rated functioning were collected multiple times during follow-up. RESULTS: Patients presented mild affective symptoms. Patient-reported mixed symptoms and irritability correlated with clinical evaluations. In analyses including confounding factors there was a statistically significant association between both mixed symptoms and irritability and stress (P < 0.0001) and between irritability and both quality of life and functioning (P < 0.0001) respectively. There was no association between mixed mood and both quality of life and functioning. CONCLUSION: Mixed symptoms and irritability can be validly self-reported using smartphones in patients with bipolar disorder. Mixed symptoms and irritability are associated with increased stress even during full or partial remission. Irritability is associated with decreased quality of life and functioning. The findings emphasize the clinical importance of identifying inter-episodic symptoms including irritability pointing towards smartphones as a valid tool.


Assuntos
Transtorno Bipolar/psicologia , Humor Irritável/classificação , Smartphone/instrumentação , Adulto , Afeto/fisiologia , Sintomas Afetivos/psicologia , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Dinamarca/epidemiologia , Feminino , Humanos , Humor Irritável/fisiologia , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Qualidade de Vida/psicologia , Autorrelato/estatística & dados numéricos , Smartphone/estatística & dados numéricos , Estresse Psicológico/psicologia
5.
Clin Genet ; 93(4): 925-928, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29266179

RESUMO

Carriers of the mitochondrial mutation m.3243A>G presents highly variable phenotypes including mitochondrial encephalomyopathy, lactoacidosis and stroke-like episodes (MELAS). We conducted a follow-up study to evaluate changes in leucocyte heteroplasmy and the clinical phenotypes in m.3243A>G carriers. Leucocyte heteroplasmy was determined by next generation sequencing covered by 100 000X reads in 32 individuals with a median follow-up of 10.2 years. Ten-year clinical follow-up is reported in 46 individuals. The annual leucocyte mutation level declined by -0.7 (±0.4) percentage points/year (P < .0001), and correlated with the level of the initial sample (ρ = -0.92, P < .0001). Eleven of 46 m.3243A>G carriers died and clinical symptoms progressed. This longitudinal study shows the decline in leucocyte m.3243A>G heteroplasmy associates with the level of the initial sample. Further, there was a high mortality among carriers.


Assuntos
DNA Mitocondrial/genética , Sequenciamento de Nucleotídeos em Larga Escala , Síndrome MELAS/genética , Criança , Feminino , Seguimentos , Heterozigoto , Humanos , Leucócitos/metabolismo , Leucócitos/patologia , Síndrome MELAS/patologia , Masculino , Mutação , Fenótipo , Estudos Prospectivos
6.
Breast Cancer Res Treat ; 163(3): 623-629, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28337664

RESUMO

PURPOSE: To determine the levels of aromatase in atypical ductal hyperplasia (ADH) lesions, tissue surrounding the ADH, and in dense and non-dense normal breast tissue. We postulated that excess aromatase in breast tissue might, through production of increased estrogen, drive the carcinogenic process. Estrogens and their metabolites are thought to contribute to the development of breast cancer through estrogen receptor-mediated mechanisms and genotoxic effects of estrogen metabolites. ADH is a benign lesion of the breast which is associated with substantially increased risk for subsequent development of breast cancer. After 25 years, approximately 30% of women with ADH develop breast cancer. In women with three or more separate ADH lesions at the same time, 47% will develop breast cancer over that time period. Another important risk factor for breast cancer is the presence of mammographically dense breast tissue. METHODS: We utilized quantitative immunochemical analysis of aromatase in biopsy tissue to test this possibility. Previously published results comparing dense with non-dense breast tissue in normal women (Vachon et al. Breast Cancer Res Treat 125:243-252, 2011) were used for comparisons with ADH. A well-characterized histochemical H-score was employed for quantitative assessment of aromatase in the various tissue studied. RESULTS: The H-score of aromatase staining was statistically significantly higher (p = 0.003) in the ADH epithelium than surrounding epithelial tissue. In order of H-score from highest to lowest were ADH, issue surrounding ADH, dense normal and non-dense normal breast tissues. The levels of aromatase in a subset of women with ADH who went on to develop breast cancer were not higher than in women who did not. CONCLUSIONS: We suggest from these studies that overexpression of aromatase in breast tissue and its resultant increase in estradiol levels may contribute to the later development of breast cancer in women with ADH.


Assuntos
Aromatase/genética , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Intraductal não Infiltrante/genética , Adulto , Biópsia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Receptores de Estrogênio/genética
7.
Diabet Med ; 34(2): 272-277, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27646695

RESUMO

AIMS: To investigate whether the use of antibiotics from infancy to adolescence influences the risk of Type 1 diabetes. METHODS: We conducted a population-based case-control study, including all Type 1 diabetes cases in Denmark among children born between 1997 and 2012 (n = 1578). Odds ratios associating Type 1 diabetes with use of antibiotics were calculated using conditional logistic regression. RESULTS: Overall, we found no association between the use of antibiotics and risk of Type 1 diabetes. Furthermore, no associations were seen specifically for broad-spectrum, narrow-spectrum, bactericidal or bacteriostatic types of antibiotics or for the most frequently used individual classes of antibiotics. No differences were observed in subgroups defined by sex or by age at time of diagnosis. However, filling five or more antibiotic prescriptions in the first 2 years of life specifically was associated with a higher odds ratio of 1.35 (95% CI 1.10-1.64). This association appeared to be driven by exposure to broad-spectrum antibiotics within the second year of life. CONCLUSION: Antibiotic exposure in childhood is generally not associated with the risk of developing Type 1 diabetes. Future studies should investigate the effects of multiple exposures to broad-spectrum antibiotics during the second year of life.


Assuntos
Antibacterianos/uso terapêutico , Diabetes Mellitus Tipo 1/epidemiologia , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Dinamarca/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Razão de Chances , Fatores de Risco
8.
Calcif Tissue Int ; 99(6): 608-615, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27572995

RESUMO

Lean mass (LM) and fat mass (FM) are closely related to bone mass (BM) in post-menopausal women, although their relative importance is unclear. Angiogenic factors which control angiogenesis may influence BM, LM and FM. The aim of the study was to compare the contribution of LM and FM to bone mineral density (BMD) and the association between these tissues and circulating angiogenic factors. The study population comprised of 392 post-menopausal women aged mean [SD] 61.8 [6.4] years. BMD was measured at the lumbar spine (LS), neck of femur and total hip (TH) by dual-energy X-ray absorptiometry (DXA). DXA scan was also used to determine LM and FM. Angiopoietin-1 and 2 (ANG-1, ANG-2) were measured by sandwich enzyme-linked immunosorbent assay. Following adjustment for confounders, significant positive independent associations were seen between LM with BMD at all skeletal sites (TH: p < 0.0001) and FM with BMD at the hip sites (TH: p = 0.004). When BMD and LM were regressed against the angiogenic factors, positive associations were seen between ANG-2 with LM (p = 0.002) and LS BMD (p = 0.05). Negative associations were observed between the ratio of ANG-1/ANG-2 with LS BMD (p = 0.014), TH BMD (p = 0.049) and LM (p = 0.029). FM and fat distribution (android/gynoid fat ratio) were negatively associated with ANG-1 (p = 0.006) and ANG-2 (p = 0.004), respectively. ANG-1 and ANG-2 may be involved in the maintenance of bone, muscle and fat mass.


Assuntos
Angiopoietina-1/sangue , Angiopoietina-2/sangue , Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Absorciometria de Fóton , Idoso , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Fator A de Crescimento do Endotélio Vascular/sangue
9.
Rehabilitation (Stuttg) ; 55(1): 26-33, 2016 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-26882135

RESUMO

OBJECTIVES AND METHODS: A rehabilitation training requires the ability to adapt to a changed living and working environment. Qualitative content analysis and quantitative studies were conducted to (1(st)) provide a definition of adaptive performance (AP) in vocational rehabilitation. (2(nd)) A self-assessment questionnaire (ReHadapt) to measure AP was developed and (3(rd)) its validity was proved by the use of exploratory (N1=344) and confirmatory factor analysis (N2=301; N3=254) for categorical variables. RESULTS: AP is a multidimensional construct which can be assessed by the ReHadapt questionnaire. The ReHadapt questionnaire consists of 30 items which are categorized to the 6 dimensions training-related AP, subject-related AP, health-related AP, social AP towards other participants, social AP towards trainers and identification with future occupation. As expected, reliability (0,81≤Cronbach's Alpha≤0,95) and validity are confirmed. Adaptive Performance predicts return to work mediated by the health-related quality of life. IMPLICATIONS: Because of its economy and applicability in everyday work-life the ReHadapt can be used for diagnostic and training in RehaAssessment(®) and RehaConsulting.


Assuntos
Adaptação Psicológica , Pessoas com Deficiência/psicologia , Reabilitação Vocacional/psicologia , Autorrelato/normas , Autoavaliação (Psicologia) , Inquéritos e Questionários/normas , Adulto , Pessoas com Deficiência/reabilitação , Feminino , Alemanha , Humanos , Masculino , Guias de Prática Clínica como Assunto , Psicometria/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Cytokine ; 71(2): 154-60, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25461393

RESUMO

Bisphosphonates (BPs) have been shown to influence angiogenesis. This may contribute to BP-associated side-effects such as osteonecrosis of the jaw (ONJ) or atypical femoral fractures (AFF). The effect of BPs on the production of angiogenic factors by osteoblasts is unclear. The aims were to investigate the effect of (1) alendronate on circulating angiogenic factors; vascular endothelial growth factor (VEGF) and angiopoietin-1 (ANG-1) in vivo and (2) zoledronate and alendronate on the production of VEGF and ANG-1 by osteoblasts in vitro. We studied 18 post-menopausal women with T score⩽-2 randomized to calcium/vitamin D only (control arm, n=8) or calcium/vitamin D and alendronate 70mg weekly (treatment arm, n=10). Circulating concentrations of VEGF and ANG-1 were measured at baseline, 3, 6 and 12months. Two human osteoblastic cell lines (MG-63 and HCC1) and a murine osteocytic cell line (MLO-Y4) were treated with zoledronate or alendronate at concentrations of 10(-12)-10(-6)M. VEGF and ANG-1 were measured in the cell culture supernatant. We observed a trend towards a decline in VEGF and ANG-1 at 6 and 12months following treatment with alendronate (p=0.08). Production of VEGF and ANG-1 by the MG-63 and HCC1 cells decreased significantly by 34-39% (p<0.01) following treatment with zoledronate (10(-9)-10(-6)M). Treatment of the MG-63 cells with alendronate (10(-7) and 10(-6)) led to a smaller decrease (25-28%) in VEGF (p<0.05). Zoledronate (10(-10)-10(-)(6)M) suppressed the production of ANG-1 by MG-63 cells with a decrease of 43-49% (p<0.01). Co-treatment with calcitriol (10(-8)M) partially reversed this zoledronate-induced inhibition. BPs suppress osteoblastic production of angiogenic factors. This may explain, in part, the pathogenesis of the BP-associated side-effects.


Assuntos
Alendronato/farmacologia , Angiopoietina-1/metabolismo , Difosfonatos/farmacologia , Imidazóis/farmacologia , Osteoblastos/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Alendronato/uso terapêutico , Angiopoietina-1/sangue , Animais , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/tratamento farmacológico , Calcitriol/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/metabolismo , Difosfonatos/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/uso terapêutico , Camundongos , Pessoa de Meia-Idade , Osteoblastos/metabolismo , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/tratamento farmacológico , Fragmentos de Peptídeos/metabolismo , Pró-Colágeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/genética , Ácido Zoledrônico
11.
Osteoporos Int ; 26(2): 749-56, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25416073

RESUMO

SUMMARY: The prevalence of sarcopenia increases with age. The diagnosis of sarcopenia relies in part on normative data on muscle mass, but these data are lacking. This study provides population-based reference data on muscle mass in young men, and these results may be used clinically for the diagnosis of sarcopenia in men. INTRODUCTION: The ageing population increases the prevalence of sarcopenia. Estimation of normative data on muscle mass in young men during the peak of anabolic hormones is necessary for the diagnosis of sarcopenia in ageing males. The purposes of this study were to provide population-based reference data on lean body mass (LBM) in young men during the time of peak levels of GH/IGF-1 and testosterone and further to apply the reference data on a population-based sample of men aged 60-74 years to estimate the prevalence of sarcopenia. METHODS: This is a cross-sectional, population-based single-centre study. Our participants are from random selection of 783 men, aged 20-29 years, and 600 men, aged 60-74 years. LBM was assessed by dual-energy X-ray absorptiometry (DXA). LBM T-scores were calculated on the basis of LBM in the young participants. Muscle function in the lower extremities was measured using a leg extension power (LEP) rig in the ageing participants. RESULTS: Total lean body mass (TLB) was (mean (SD)) 64.7 kg (6.8) in the young and 60.4 kg (6.4) in the ageing men (p<0.001). Lower extremity lean mass (LELB) was 22.0 kg (2.6) in the young and 19.2 kg (2.4) in the ageing men (p<0.001). In the ageing men, TLB and LELB T-scores were -0.64 (0.94) and -1.09 (0.94). A total of 4.8 and 8.5% had a TLB or LELB T-score of less than -2 and a LEP in the lowest quartile. CONCLUSIONS: This study provides population-based reference data on LBM in men, and these data may be used clinically for the diagnosis of sarcopenia.


Assuntos
Envelhecimento/patologia , Músculo Esquelético/anatomia & histologia , Sarcopenia/diagnóstico , Adulto , Idoso , Envelhecimento/fisiologia , Antropometria/métodos , Composição Corporal/fisiologia , Índice de Massa Corporal , Dinamarca/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiologia , Tamanho do Órgão/fisiologia , Prevalência , Valores de Referência , Sarcopenia/epidemiologia , Sarcopenia/fisiopatologia , Adulto Jovem
12.
Psychol Med ; 45(13): 2691-704, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26220802

RESUMO

BACKGROUND: The number of studies on electronic self-monitoring in affective disorder and other psychiatric disorders is increasing and indicates high patient acceptance and adherence. Nevertheless, the effect of electronic self-monitoring in patients with bipolar disorder has never been investigated in a randomized controlled trial (RCT). The objective of this trial was to investigate in a RCT whether the use of daily electronic self-monitoring using smartphones reduces depressive and manic symptoms in patients with bipolar disorder. METHOD: A total of 78 patients with bipolar disorder according to ICD-10 criteria, aged 18-60 years, and with 17-item Hamilton Depression Rating Scale (HAMD-17) and Young Mania Rating Scale (YMRS) scores ≤17 were randomized to the use of a smartphone for daily self-monitoring including a clinical feedback loop (the intervention group) or to the use of a smartphone for normal communicative purposes (the control group) for 6 months. The primary outcomes were differences in depressive and manic symptoms measured using HAMD-17 and YMRS, respectively, between the intervention and control groups. RESULTS: Intention-to-treat analyses using linear mixed models showed no significant effects of daily self-monitoring using smartphones on depressive as well as manic symptoms. There was a tendency towards more sustained depressive symptoms in the intervention group (B = 2.02, 95% confidence interval -0.13 to 4.17, p = 0.066). Sub-group analysis among patients without mixed symptoms and patients with presence of depressive and manic symptoms showed significantly more depressive symptoms and fewer manic symptoms during the trial period in the intervention group. CONCLUSIONS: These results highlight that electronic self-monitoring, although intuitive and appealing, needs critical consideration and further clarification before it is implemented as a clinical tool.


Assuntos
Antipsicóticos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Depressão/diagnóstico , Smartphone/instrumentação , Adolescente , Adulto , Transtorno Bipolar/diagnóstico , Feminino , Humanos , Classificação Internacional de Doenças , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Método Simples-Cego , Resultado do Tratamento , Adulto Jovem
13.
Clin Endocrinol (Oxf) ; 78(5): 743-51, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23106255

RESUMO

CONTEXT: Ageing in men is associated with changes in levels of sex hormones. OBJECTIVE: To evaluate differences in sex hormones in young and elderly men and the significance of comorbidity and fat mass on sex hormones in elderly men. DESIGN: Cross-sectional. PATIENTS: Seven hundred and eighty-three men aged 20-29 years and 600 men aged 60-74 years randomly recruited from the background population. MEASUREMENTS: Sex hormones and sex hormone-binding globulin (SHBG) were measured, and reference intervals were determined in healthy individuals in both groups and in elderly men stratified according to whether they were obese or lean (waist circumference ≥102 cm). RESULTS: Sex hormones were lower and SHBG higher in elderly men compared with the young cohort. Lower cut-offs for total testosterone (TT) in healthy, young and elderly men were similar [Lower cut-off (95% CI): Young: 11·7 (11·2-12·1) vs elderly: 11·2 (10·3-12·1) nmol/l], but lower and higher cut-offs of bioavailable testosterone (BT) and free testosterone (FT) were higher in young men. Higher levels of androgens were found in healthy elderly men compared with those with a chronic disease or obesity. Androgens were inversely associated with central fat mass (CFM), whereas SHBG was inversely and directly associated with CFM and lower extremity fat mass, respectively, in both young and elderly men. CONCLUSION: Reference intervals for TT were comparable in healthy young and elderly men, but reference intervals for FT and BT were lower in elderly men due to higher levels of SHBG. Androgens and SHBG were lower in elderly men with chronic disease and inversely associated with CFM.


Assuntos
Testosterona/sangue , Adulto , Fatores Etários , Idoso , Índice de Massa Corporal , Humanos , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/metabolismo , Adulto Jovem
14.
Osteoporos Int ; 24(2): 633-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22581294

RESUMO

SUMMARY: This study showed that regional bone blood flow and (18)F-fluoride bone plasma clearance measured by positron emission tomography are three times lower at the hip than the lumbar spine. INTRODUCTION: Measurements of effective bone plasma flow (K (1)), bone plasma clearance (K ( i )) and standardised uptake values (SUV) using (18)F-fluoride positron emission tomography ((18)F-PET) provide a useful means of studying regional bone metabolism at different sites in the skeleton. This study compares the regional (18)F-fluoride kinetics and SUV at the hip and lumbar spine (LS). METHODS: Twelve healthy postmenopausal women with no history of metabolic bone disease apart from two with untreated osteoporosis were recruited. Each subject underwent 60-min dynamic (18)F-PET scans at the LS and proximal femur two weeks apart. K (1), K ( i ) and SUV were measured at the LS (mean of L(1)-L(4)), femoral neck (FN), total hip (TH) and femoral shaft (FS). Differences between sites were assessed using the nonparametric Kruskal-Wallis test with a Bonferroni correction for multiple comparisons. RESULTS: Values of K (1), K ( i ) and SUV at the FN, TH and FS were three times lower than at the LS (p = 0.003). Amongst the proximal femur sites, K ( i ) and SUV were lower at the FS compared with the FN and TH, and SUV was lower at the TH compared with the FN (all p < 0.05). The volume of distribution was lower at the TH and FS compared with the LS (p < 0.05). CONCLUSION: The lower values of K (1), K ( i ) and SUV at the hip suggest that lower bone blood flow in the proximal femur is an important factor explaining the principal reason for the differences in bone fluoride kinetics between the LS and hip sites.


Assuntos
Articulação do Quadril/metabolismo , Vértebras Lombares/metabolismo , Absorciometria de Fóton , Densidade Óssea/fisiologia , Feminino , Colo do Fêmur/irrigação sanguínea , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/metabolismo , Colo do Fêmur/fisiologia , Fluordesoxiglucose F18 , Articulação do Quadril/irrigação sanguínea , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/fisiologia , Humanos , Vértebras Lombares/irrigação sanguínea , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , Pessoa de Meia-Idade , Projetos Piloto , Tomografia por Emissão de Pósitrons/métodos , Pós-Menopausa/fisiologia , Compostos Radiofarmacêuticos , Fluxo Sanguíneo Regional
15.
Calcif Tissue Int ; 92(5): 467-76, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23370486

RESUMO

The interaction between muscle and bone is complex. The aim of this study was to investigate if variations in the muscle genes myostatin (MSTN), its receptor (ACVR2B), myogenin (MYOG), and myoD1 (MYOD1) were associated with fracture risk, bone mineral density (BMD), bone mineral content (BMC), and lean body mass. We analyzed two independent cohorts: the Danish Osteoporosis Prevention Study (DOPS), comprising 2,016 perimenopausal women treated with hormone therapy or not and followed for 10 years, and the Odense Androgen Study (OAS), a cross-sectional, population-based study on 783 men aged 20-29 years. Nine tag SNPs in the four genes were investigated. In the DOPS, individuals homozygous for the variant allele of the MSTN SNP rs7570532 had an increased risk of any osteoporotic fracture, with an HR of 1.82 (95 % CI 1.15-2.90, p = 0.01), and of nonvertebral osteoporotic fracture, with an HR of 2.02 (95 % CI 1.20-3.41, p = 0.01). The same allele was associated with increased bone loss (BMC) at the total hip of 4.1 versus 0.5 % in individuals either heterozygous or homozygous for the common allele (p = 0.006), a reduced 10-year growth in bone area at the total hip of 0.4 versus 2.2 and 2.3 % in individuals heterozygous or homozygous for the common allele, respectively (p = 0.01), and a nonsignificantly increased 10-year loss of total-hip BMD of 4.4 versus 2.7 and 2.9 % in individuals heterozygous or homozygous for the common allele, respectively (p = 0.08). This study is the first to demonstrate an association between a variant in MSTN and fracture risk and bone loss. Further studies are needed to confirm the findings.


Assuntos
Osso e Ossos/patologia , Músculos/patologia , Fraturas por Osteoporose/etnologia , Fraturas por Osteoporose/genética , Polimorfismo Genético , Receptores de Activinas Tipo II/genética , Adulto , Densidade Óssea , Proliferação de Células , Estudos de Coortes , Dinamarca , Densitometria , Feminino , Fêmur/patologia , Fraturas Ósseas/patologia , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Proteína MyoD/genética , Miogenina/genética , Miostatina/genética , Fraturas por Osteoporose/patologia , Fenótipo , Estudos Prospectivos , População Branca , Adulto Jovem
16.
Microb Ecol ; 65(4): 852-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23325465

RESUMO

Early steps in the emergence of the discipline of "Oceans and Human Health" are charted in the USA and discussed in relation to past and present marine environment and human health research activities in Europe. Differences in terminology are considered, as well as differences in circumstances related to the various seas of Europe and the intensity of human coastal activity and impact. Opportunities to progress interdisciplinary research are described, and the value of horizon scanning for the early identification of emerging issues is highlighted. The challenges facing researchers and policymakers addressing oceans and human health issues are outlined and some suggestions offered regarding how further progress in research and training into both the risks and benefits of Oceans and Human Health might be made on both sides of the Atlantic.


Assuntos
Ecossistema , Atividades Humanas , Água do Mar/química , Animais , Saúde , Humanos , Oceanos e Mares
17.
Rev Sci Instrum ; 94(3): 033511, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37012804

RESUMO

High-power, short-pulse laser-driven fast electrons can rapidly heat and ionize a high-density target before it hydrodynamically expands. The transport of such electrons within a solid target has been studied using two-dimensional (2D) imaging of electron-induced Kα radiation. However, it is currently limited to no or picosecond scale temporal resolutions. Here, we demonstrate femtosecond time-resolved 2D imaging of fast electron transport in a solid copper foil using the SACLA x-ray free electron laser (XFEL). An unfocused collimated x-ray beam produced transmission images with sub-micron and ∼10 fs resolutions. The XFEL beam, tuned to its photon energy slightly above the Cu K-edge, enabled 2D imaging of transmission changes induced by electron isochoric heating. Time-resolved measurements obtained by varying the time delay between the x-ray probe and the optical laser show that the signature of the electron-heated region expands at ∼25% of the speed of light in a picosecond duration. Time-integrated Cu Kα images support the electron energy and propagation distance observed with the transmission imaging. The x-ray near-edge transmission imaging with a tunable XFEL beam could be broadly applicable for imaging isochorically heated targets by laser-driven relativistic electrons, energetic protons, or an intense x-ray beam.

18.
Diabetologia ; 55(12): 3204-12, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22955993

RESUMO

AIMS/HYPOTHESIS: Low birthweight (BW) is associated with increased risk of type 2 diabetes. We compared glucose metabolism in adult BW-discordant monozygotic (MZ) twins, thereby controlling for genetic factors and rearing environment. METHODS: Among 77,885 twins in the Danish Twin Registry, 155 of the most BW-discordant MZ twin pairs (median BW difference 0.5 kg) were assessed using a 2 h oral glucose tolerance test with sampling of plasma (p-)glucose, insulin, C-peptide, glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1. HOMA for beta cell function (HOMA-ß) and insulin resistance (HOMA-IR), and also insulin sensitivity index (BIGTT-SI) and acute insulin response (BIGTT-AIR), were calculated. Subgroup analyses were performed in those with: (1) double verification of BW difference; (2) difference in BW >0.5 kg; and (3) no overt metabolic disease (type 2 diabetes, hyperlipidaemia or thyroid disease). RESULTS: No intra-pair differences in p-glucose, insulin, C-peptide, incretin hormones, HOMA-ß, HOMA-IR or BIGTT-SI were identified. p-Glucose at 120 min was higher in the twins with the highest BW without metabolic disease, and BIGTT-AIR was higher in those with the highest BW although not in pairs with a BW difference of >0.5 kg. CONCLUSIONS/INTERPRETATION: BW-discordant MZ twins provide no evidence for a detrimental effect of low BW on glucose metabolism in adulthood once genetic factors and rearing environment are controlled for.


Assuntos
Peso ao Nascer , Glicemia/metabolismo , Peptídeo C/sangue , Diabetes Mellitus Tipo 2/sangue , Suscetibilidade a Doenças/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Gêmeos Monozigóticos , Adulto , Idoso , Análise de Variância , Dinamarca/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Suscetibilidade a Doenças/epidemiologia , Feminino , Intolerância à Glucose , Teste de Tolerância a Glucose , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Resistência à Insulina , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários
19.
Osteoporos Int ; 23(2): 521-31, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21409435

RESUMO

SUMMARY: Risk factors for fractures were assessed in a random sample of 4,696 elderly men followed for 5.4 years. Results highlighted the importance of assessment of falls and dizziness as well as novel risk factors including frequent urination and erectile dysfunction. INTRODUCTION: Knowledge about risk factors for fracture in men is limited. The aim of this study was to evaluate factors potentially associated with fracture risk in men. METHODS: A questionnaire enquiring about potential risk factors for fractures in men was posted to a random sample of 9,314 men aged 60-74 years. A completed questionnaire was returned by 4,696 (50.4%). Follow-up on incident fractures over 5.4 years was performed using public registries. RESULTS: During the study, 203 individuals experienced a first clinical fracture, of which 85 patients were considered osteoporotic (9 in humerus, 10 vertebral, 32 in the hip and 34 in the forearm). Cox proportional hazard regression models were used to evaluate risk factors for any and osteoporotic fractures. The following variables were found to be associated with increased risk of any fracture in adjusted models family history of a hip fracture (HR; 95%CI: 1.56; 1.05-2.33), falls (2-4/year: 2.10; 1.35-3.27, >4/year: 2.46; 1.12-5.41, both compared to no falls), dizziness (2.36; 1.51-3.71), erectile dysfunction (1.41; 1.06-1.87) and frequent urination (2.06; 1.26-3.39). Similarly, falls (2.36; 1.45-3.86), dizziness (2.83; 1.52-5.25), erectile dysfunction (2.01; 1.30-3.09) and pulmonary illness (1.90; 1.03-3.53) were associated with increased risk of osteoporotic fractures in adjusted models. CONCLUSION: These results underline the importance of assessment of dizziness, falls and those with a family history of hip fracture. Frequent urination and erectile dysfunction were independently associated with increased fracture risk. Although the mechanism of association is unknown, these variables are likely to be indicators of frailty or hypogonadism.


Assuntos
Fraturas Ósseas/etiologia , Acidentes por Quedas/estatística & dados numéricos , Idoso , Dinamarca/epidemiologia , Tontura/complicações , Tontura/epidemiologia , Disfunção Erétil/complicações , Disfunção Erétil/epidemiologia , Fraturas Ósseas/epidemiologia , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Movimento , Obesidade/complicações , Obesidade/epidemiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Estudos Prospectivos , Fatores de Risco , Fatores Socioeconômicos , Transtornos Urinários/complicações , Transtornos Urinários/epidemiologia
20.
Osteoporos Int ; 23(1): 183-91, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21359668

RESUMO

UNLABELLED: Osteoporosis in men is underdiagnosed. The use of dual-emission X-ray absorptiometry (DXA) was evaluated in almost 5,000 men aged 60-74 years. DXA was infrequent, despite the presence of multiple risk factors for osteoporosis and a high FRAX score. There is a need for improved targeting of DXA scans for men at high risk. INTRODUCTION: Clinical and socioeconomic factors associated with bone mass assessment (DXA) in men have seldom been evaluated. This study aimed to evaluate factors associated with the use of DXA in men. METHODS: Self-report information on prior DXA and osteoporosis risk factors were obtained from the baseline data of a study investigating the health perspectives of men aged 60-75 years. Socioeconomic and comorbidity data were retrieved from national registers. The FRAX algorithm was used to calculate the absolute fracture risk. Regression analysis was used to identify factors significantly associated with previous DXA scan. RESULTS: Of the 4,696 men returning questionnaires (50% response rate), 2.7% had prior DXA but 48% had at least one osteoporosis risk factor. Previous DXA was associated with oral glucocorticoid treatment, secondary osteoporosis, rheumatoid arthritis, fracture after age 50, falls within the previous year, smoking, and higher age. Twenty-one percent of men with prior DXA and 10% of men without prior DXA had greater than 20% risk of a major osteoporotic fracture within the next 10 years. One third of those with previous DXA had none of the FRAX osteoporosis risk factors. When family history of osteoporosis and falls were included as risk factors, 18% with previous DXA had no clinical risk factors for osteoporosis. CONCLUSIONS: DXA was infrequent in this group of elderly men, despite the presence of risk factors for osteoporosis. DXA was also used despite a low fracture risk. There is a need for improved targeting of DXA scans for men at high risk.


Assuntos
Absorciometria de Fóton/estatística & dados numéricos , Osteoporose/diagnóstico , Idoso , Algoritmos , Composição Corporal , Comorbidade , Estudos Transversais , Dinamarca/epidemiologia , Predisposição Genética para Doença , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Osteoporose/etiologia , Seleção de Pacientes , Fatores de Risco , Fatores Socioeconômicos
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