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1.
J Med Internet Res ; 24(4): e31889, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35436220

RESUMO

BACKGROUND: Despite the wealth of evidence regarding effective health behavior change techniques using digital interventions to focus on residents of high-income countries, there is limited information of a similar nature for low- and middle-income countries. OBJECTIVE: The aim of this review is to identify and describe the available literature on effective social media-based behavior change interventions within low- and middle-income countries. METHODS: This systematic review was conducted in accordance with the 2009 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We searched PubMed, Embase, Elsevier, CINAHL, PsycInfo, and Global Index Medicus, and the final search was conducted on April 6, 2021. We excluded studies published before 2000 because of the subject matter. We included studies that evaluated interventions conducted at least partly on a social media platform. RESULTS: We identified 1832 studies, of which 108 (5.89%) passed title-abstract review and were evaluated by full-text review. In all, 30.6% (33/108) were included in the final analysis. Although 22 studies concluded that the social media intervention was effective, only 13 quantified the level of social media engagement, of which, few used theory (n=8) or a conceptual model (n=5) of behavior change. CONCLUSIONS: We identified gaps in the settings of interventions, types and sectors of interventions, length of follow-up, evaluation techniques, use of theoretical and conceptual models, and discussions of the privacy implications of social media use. TRIAL REGISTRATION: PROSPERO CRD42020223572; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=223572.


Assuntos
Mídias Sociais , Países em Desenvolvimento , Comportamentos Relacionados com a Saúde , Humanos
2.
Contemp Clin Trials Commun ; 16: 100460, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31650078

RESUMO

BACKGROUND: Excess weight retention among postpartum women is a risk factor for long term obesity, and African American women are at heightened risk. New solutions, including digital technologies and community-based approaches are needed. Digital platforms, like social media, provide opportunity for participant co-creation (i.e., content co-generated by users and investigators) of health messages and may allow for adaptation of evidence-based weight management interventions to reduce participant burden. The BeFAB intervention, a branded, digital weight management program, tests this hypothesis. METHODS: BeFAB content comprises culturally-specific nutrition, physical activity, stress management, health information seeking and related weight management messages and content designed for African American women. The intervention is 12 weeks in duration, delivered through a mobile phone app, and is designed to target specific behavioral predictor beliefs and attitudinal measures (e.g., self-efficacy to achieve weight management goals) based on the culturally-specific content. Use of personal, culturally-specific video-based narratives in the app, and through a secret Facebook group, are included to help model HEAL behaviors and brand BeFAB. Intervention development consisted of iterative formative research steps to engage African American women. The program will be evaluated in a small randomized trial among patients recruited at a clinical facility. CONCLUSIONS: BeFAB applies evidence-based content using a promising digital approach. It is novel in its use of branding, culturally-tailored content, and digital technology for behavior change.Evaluation of BeFAB will contribute to the growing literature on digital health behavior change interventions for weight management.

3.
Health Educ Res ; 33(2): 125-144, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29329436

RESUMO

Immigrant Latino youth represent a high-risk subgroup that should be targeted with health promotion efforts. However, there are considerable barriers to engagement in health-related programming. Little is known about the engagement possibilities of social marketing campaigns and digital strategies for traditionally 'hard-to-reach' immigrants, underscoring the importance of testing these techniques with immigrant Latino adolescents. We developed and piloted a place-based social marketing campaign in coordination with the branded, Positive Youth Development-based (PYD) Adelante intervention targeting risk factors for co-occurring youth substance abuse, sexual risk and violence. Building on prior research, we conducted a four-phase formative research process, and planned the Adelante social marketing campaign based on findings from one group interview and ongoing consultation with Adelante staff (n=8) and four focus groups with youth (n=35). Participants identified four overarching campaign themes, and suggested portrayal of resilient, proud youth who achieved goals despite adversity. Youth guided selection of campaign features and engagement strategies, including message/visual content, stylistic elements, and a mixed language approach. We developed a 12-month campaign to be delivered via print ads, multi-platform social media promotion, contests, youth-generated videos, blog posts, and text messaging. We describe the process and outcome of campaign development and make recommendations for future campaigns.


Assuntos
Emigrantes e Imigrantes , Promoção da Saúde/métodos , Hispânico ou Latino , Comportamento Sexual , Marketing Social , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Violência/prevenção & controle , Adolescente , América Central/etnologia , Criança , Feminino , Grupos Focais , Humanos , Masculino , Maryland , Mídias Sociais , Adulto Jovem
4.
Hum Reprod ; 29(9): 2041-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25035436

RESUMO

STUDY QUESTION: Are arterial stiffness, carotid intima-media thickness and diastolic dysfunction increased in young women with polycystic ovary syndrome (PCOS) independently of the effects of obesity? SUMMARY ANSWER: Insulin resistance and central obesity are associated with subclinical cardiovascular dysfunction in young women, but a diagnosis of PCOS does not appear to confer additional risk at this age. WHAT IS KNOWN ALREADY: Some studies have shown that young women with PCOS may have increased measures of cardiovascular risk, including arterial stiffness, carotid intima-media thickness and myocardial dysfunction. However, it is difficult to establish how much of this risk is due to PCOS per se and how much is due to obesity and insulin resistance, which are common in PCOS and themselves associated with greater vascular risk. STUDY DESIGN, SIZE, DURATION: This cross-sectional study comprised 84 women with PCOS and 95 healthy volunteers, aged 16-45 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was conducted in a university hospital. Subjects underwent a comprehensive assessment of body composition (including computed tomography (CT) assessment of visceral fat; VF), measurements of arterial stiffness (aortic pulse wave velocity; aPWV), common carotid intima-media thickness (ccIMT), diastolic function (longitudinal tissue velocity; e':a') and endocrinological measures. A sample size of 80 in each group gave 80% power for detecting a difference of 0.45 m/s in aPWV or a difference of 0.25 in e':a'. MAIN RESULTS AND THE ROLE OF CHANCE: After adjustment for age and body mass index (BMI), PCOS subjects had a greater insulin response (insulin area under the curve-IAUC) following glucose challenge (adjusted difference [AD] 35 900 pmol min/l, P < 0.001) and higher testosterone (AD 0.57 nmol/l, P < 0.001) and high molecular weight adiponectin than controls (AD 3.01 µg/ml, P = 0.02), but no significant differences in aPWV (AD -0.13 m/s, P = 0.33), ccIMT (AD -0.01 mm, P = 0.13), or e':a' (AD -0.01, P = 0.86) were observed. After adjustment for age, height and central pulse pressure, e':a' and aPWV were associated with logVF and IAUC. ccIMT was not related to logVF. The relationships between e':a' or aPWV and insulin resistance were only partly attenuated by adjusting for logVF. There was no significant relationship between aPWV or e':a' and either testosterone or adiponectin. LIMITATIONS, REASONS FOR CAUTION: The study recruited young women meeting the Rotterdam criteria for PCOS diagnosis; hence our findings may not be generalizable to older patients or those meeting other definitions of the syndrome. Biochemical hyperandrogenism was based solely on measurement of total testosterone. Cases and controls were not matched in advance for age and BMI, although the influence of these variables on the cardiovascular outcome measures was adjusted for. WIDER IMPLICATIONS OF THE FINDINGS: This study shows that central arterial stiffness and diastolic dysfunction are not increased in young women with PCOS, whereas they are associated with both insulin resistance and central obesity. Obesity thus represents the greatest modifiable risk factor for cardiovascular disease in young women with PCOS and lifestyle measures which target weight reduction are critical. STUDY FUNDING/COMPETING INTERESTS: This study received no specific grant support from any funding body. The authors have no conflicts of interest to declare.


Assuntos
Doenças Cardiovasculares/complicações , Resistência à Insulina , Obesidade Abdominal/complicações , Síndrome do Ovário Policístico/complicações , Rigidez Vascular , Adolescente , Adulto , Composição Corporal , Feminino , Testes de Função Cardíaca , Humanos , Pessoa de Meia-Idade , Medição de Risco
5.
J Radiol Prot ; 34(2): 435-44, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24894021

RESUMO

Gamma emitting radioactive by-products generated during the cyclotron irradiation of (18)O labelled water by protons to produce (18)FDG (fluorodeoxyglucose) for positron emission tomography are well characterised. However, the production of tritium ((3)H) through the (18)O(p,t)(16)O nuclear reaction has not been investigated in detail. The aim of this study was to measure tritium activity produced during a large number of (18)FDG production runs in order to obtain a better perspective on its impact on radioactive waste management, particularly as regards storage and disposal. Tritium was assayed by liquid scintillation counting in recovered (18)O water from 24 separate production runs. The mean (SD) values of activity and activity concentration were 170 (20) kBq and 81 (8) kBq ml(-1) respectively. Both quantities were positively correlated with the activity of (18)F. Tritium was detected in much lower concentration in water used to rinse the target vessel. The activity of tritium is such that it is exempt from regulatory control and may be combined with bulk non-active waste for disposal as Very Low Level Waste. However, variations in the irradiation conditions or the procedures for the collection of recovered water might result in its classification as Low Level Waste, necessitating a more complex disposal regime.


Assuntos
Contaminação de Medicamentos/prevenção & controle , Fluordesoxiglucose F18/análise , Fluordesoxiglucose F18/síntese química , Marcação por Isótopo/métodos , Tomografia por Emissão de Pósitrons , Trítio/análise , Teste de Materiais , Resíduos Radioativos , Compostos Radiofarmacêuticos/análise , Compostos Radiofarmacêuticos/síntese química , Trítio/química
6.
BJOG ; 121(13): 1596-603, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24816317

RESUMO

OBJECTIVE: To assess circulating biochemical indices of endothelial function and nitro-oxidative stress in women with polycystic ovary syndrome (PCOS). DESIGN: Case-control study. POPULATION: Seventeen women with PCOS and eighteen age- and body mass index-matched healthy volunteers. METHODS: Nitric oxide (NO) metabolite levels were assessed by chemiluminescence. Electron paramagnetic resonance spectroscopy with spin trapping was used to assess oxidative stress ex vivo and in vitro. Antioxidant capacity was measured using oxygen radical absorbance. MAIN OUTCOME MEASURES: Biochemical indices of endothelial function, including NO metabolites, lipid-derived radicals and antioxidant capacity. RESULTS: Plasma NO metabolites were similar in the two groups (nitrite: 257±116 nmol/l [PCOS], 261±135 nmol/l [controls] P=0.93; nitrate: 27±7 µmol/l [PCOS], 26±6 µmol/l [controls] P=0.89). Alkoxyl free radicals (lipid-derived) were detected as the dominant species, but levels were not different between women with PCOS and controls whether measured directly ex vivo (median 7.2 [range 0.17-16.73]e6 arbitrary units [a.u.] and 7.2 [1.7-11.9]e6 a.u., respectively, P=0.57) or when stimulated in vitro to test radical generation capacity (1.23 [0.3-5.62]e7 a.u. and 1.1 [0.48-15.7]e7 a.u. respectively, P=0.71). In regression analysis, visceral fat area was independently associated with in vitro oxidative potential (ß=0.6, P=0.002). Total plasma antioxidant capacity (94±30% [PCOS], 79±24% [controls], P=0.09) and plasma hydroperoxides (7.5±4 µmol/l [PCOS], 6.7±5 µmol/l [controls], P=0.21) were not different between groups. However, lipophilic antioxidant capacity was lower in women with PCOS compared with controls (92±32 and 125±48%, respectively, P=0.02). CONCLUSIONS: Young overweight women with PCOS display a reduced lipophilic antioxidant capacity compared with healthy volunteers, but no change in circulating free radicals or nitro-oxidative stress.


Assuntos
Endotélio/metabolismo , Peróxidos Lipídicos/sangue , Óxido Nítrico/sangue , Obesidade/sangue , Estresse Oxidativo , Síndrome do Ovário Policístico/sangue , Espécies Reativas de Oxigênio/sangue , Adolescente , Adulto , Glicemia , Índice de Massa Corporal , Estudos de Casos e Controles , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Humanos , Resistência à Insulina , Gordura Intra-Abdominal , Medições Luminescentes , Pessoa de Meia-Idade , Obesidade/complicações , Sobrepeso/sangue , Sobrepeso/complicações , Síndrome do Ovário Policístico/complicações , Análise de Regressão , Gordura Subcutânea , Adulto Jovem
7.
Soc Sci Med ; 110: 18-25, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24704890

RESUMO

Like commercial marketing, social marketing uses the 4 "Ps" and seeks exchange of value between the marketer and consumer. Behaviors such as handwashing, and products such as those for oral rehydration treatment (ORT), can be marketed like commercial products in developing countries. Although social marketing in these areas is growing, there has been no systematic review of the current state of practice, research and evaluation. We searched the literature for published peer-reviewed studies available through major online publication databases. We identified manuscripts in the health, social science, and business literature on social marketing that used at least one of the 4 Ps of marketing and had a behavioral objective targeting the behaviors or products related to improving water and sanitation. We developed formalized decision rules and applied them in identifying articles for review. We initially identified 117 articles and reviewed a final set of 32 that met our criteria. Social marketing is a widespread strategy. Marketing efforts have created high levels of awareness of health threats and solutions, including behavior change and socially marketed products. There is widespread use of the 4 Ps of marketing, with price interventions being the least common. Evaluations show consistent improvements in behavioral mediators but mixed results in behavior change. Interventions have successfully used social marketing following widely recommended strategies. Future evaluations need to focus on mediators that explain successful behavior change in order to identify best practices and improve future programs. More rigorous evaluations including quasi-experimental designs and randomized trials are needed. More consistent reporting of evaluation results that permits meta-analysis of effects is needed.


Assuntos
Promoção da Saúde/métodos , Saneamento , Marketing Social , Água , Países em Desenvolvimento , Comportamentos Relacionados com a Saúde , Humanos
8.
Ann Hum Biol ; 39(1): 19-27, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22117592

RESUMO

BACKGROUND AND AIM: To identify the distribution and explore the relationship between ACTN3 genotypes and power and body composition phenotypes. SUBJECTS AND METHODS: Case control and association studies were employed using a homogeneous group of players (n = 102) and a control group (n = 110). Power-related phenotypes were measured using the counter movement jump (CMJ) and body composition phenotypes by dual-energy X-ray absorptiometry (DXA). Statistics used were Pearson's chi-square, ANCOVA, coefficients of correlation and independent t-tests. Genotyping was carried out using polymerase chain reaction followed by enzymatic Ddel digestion. RESULTS: Genotype proportions of players were compared with controls (p = 0.07). No significant genotype differences occurred between forwards or backs (p = 0.822) or within-forwards (p = 0.882) or within-backs (p = 0.07). Relative force and velocity were significantly larger in backs, power significantly greater in forwards; in body composition, all phenotypes were significantly greater in forwards than backs. Correlations between phenotypes were greater for the RX genotype (p = 0.05-0.01). CONCLUSIONS: Relationships between ACTN3 genotypes and power or body composition-related phenotypes were not significant. As fat increased, power-related phenotypes decreased. As body composition increased, power-related phenotypes increased.


Assuntos
Actinina/genética , Atletas , Composição Corporal/genética , Futebol Americano , Adolescente , Fenômenos Biomecânicos/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene/genética , Genótipo , Humanos , Masculino , Adulto Jovem
9.
J Sports Med Phys Fitness ; 50(3): 350-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20842098

RESUMO

AIM: The present study examined the hypothesis that there were no significant differences between forwards and backs in the elements of leg power between the ID and DD genotypes of the ACE (I/D) gene in developing young adult Rugby Union players. METHODS: Sixty-eight players were recruited to identify the distribution of genotypes between forwards and backs. Fifty-eight players were investigated for leg power. Forwards (n=28) comprised 15 ID and 13 DD genotypes, and backs (n=30) 19 ID and 11 DD genotypes. Leg power was measured on a force platform using a counter movement jump; the parameters of interest were peak and relative force, peak and relative power, displacement and velocity. The three-primer polymerase chain reaction was used to assay the region of interest for I and D variants of the ACE gene. The distribution of genotypes was determined by chi-square and comparisons between forwards and backs made using the independent t-test. RESULTS: No significant differences were identified in the distribution of genotypes between forwards and backs (χ2=2.2, P=0.336). However, significant differences were identified between forwards and backs in a number of components of leg power. Backs had significantly larger values than forwards for relative force (1.50 vs. 1.30 Wt%, P=0.001) and relative power (27.1 vs. 24.3 W.kg-1, P=0.034) for the ID genotype, whereas backs had significantly larger values than forwards for displacement (0.42 vs. 0.38 m, P=0.049) and velocity (2.76 vs. 2.55 m.s.(-1), P=0.007) for the DD genotype. CONCLUSION: The characteristics of leg power identified will enhance the functional requirements of players according to playing position and commitment.


Assuntos
Desempenho Atlético/fisiologia , Futebol Americano/fisiologia , Perna (Membro)/fisiologia , Força Muscular/fisiologia , Peptidil Dipeptidase A/genética , Absorciometria de Fóton , Antropometria , Composição Corporal , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Estudos Transversais , Genótipo , Humanos , Masculino , Adulto Jovem
10.
Chron Respir Dis ; 6(2): 81-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19411568

RESUMO

Matrix metalloproteinase-9 (MMP-9) has been implicated in airways injury in chronic obstructive pulmonary disease (COPD). Osteoporosis is common in patients with COPD, and MMP-9 is an indicator of activated osteoclasts. We hypothesized that circulating MMP-9 would be related to bone mineral density (BMD) in COPD. We explored the relationship between MMP-9, tissue inhibitors of metalloproteinases (TIMP)-1 and -2, and BMD status in patients with COPD. A total of 70 clinically stable patients with confirmed COPD and 39 control subjects underwent spirometry, dual-energy x-ray absorptiometry to determine BMD, and venous sampling for measurement of cytokines and MMP-9 and TIMP-1 and -2. In patients, circulating MMP-9 was increased: mean (SD) 38.5 (2.2) compared with control subjects 20.1 (2.0) ng/mL, P < 0.001, whereas TIMP-1 and -2 were not different. In the patients, MMP-9 was greater in those with osteoporosis, compared with those with osteopenia, no bone disease or control subjects, and patients with osteopenia had greater MMP-9 than control subjects. The adjusted receiver operating characteristics curve area for MMP-9 detecting osteoporosis was 0.86. Patients had elevated systemic inflammatory mediators compared with control subjects, but these were unrelated to bone status. Increased circulating MMP-9 in patients with COPD was related to the presence of osteoporosis and not to lung function. MMP-9 may be a biomarker of increased bone resorption.


Assuntos
Metaloproteinase 9 da Matriz/sangue , Osteoporose/enzimologia , Osteoporose/epidemiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/enzimologia , Idoso , Biomarcadores/sangue , Densidade Óssea , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Volume Expiratório Forçado , Humanos , Mediadores da Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Doença Pulmonar Obstrutiva Crônica/sangue , Curva ROC , Índice de Gravidade de Doença , Inibidor Tecidual de Metaloproteinase-1/sangue , Inibidor Tecidual de Metaloproteinase-2/sangue
11.
Physiol Meas ; 30(7): N53-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19436083

RESUMO

Ryo et al (2005 Diabetes Care 28 451-3) reported a new method for measuring the visceral fat area (VFA) by combining abdominal bioelectrical impedance analysis (BIA) with measurement of waist circumference (WC), but very few methodological details were provided. Furthermore, the study did not test the use of WC alone as an indicator of VFA even though others had previously reported a strong correlation. We sought to determine the optimal measurement technique and analysis for measuring VFA by abdominal BIA and WC. 18 volunteers (age 23-64 years) underwent measurement of WC, abdominal impedance (Bodystat 500 four-electrode system) and a single cross-sectional CT scan at the umbilicus. VFA derived using WC(3) and measurements of abdominal impedance from electrode pairs sited at the flank predicted the value of VFA measured by CT with correlation r = 0.904 (p < 0.0001); the optimizing power of WC was 3.3 (r = 0.905). However, the use of WC(1.9) alone, without involving BIA at all, provided a similar correlation (r = 0.923). Our small preliminary study shows that abdominal BIA is potentially a practicable non-invasive technique for measurement of VFA but casts doubt on whether it adds any value to the use of WC alone. Larger studies are now required to test this finding.


Assuntos
Impedância Elétrica , Gordura Intra-Abdominal/fisiologia , Circunferência da Cintura/fisiologia , Abdome , Adulto , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade
12.
Respir Med ; 102(5): 651-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18308533

RESUMO

BACKGROUND: Osteoporosis is common in patients with COPD. Previously we have reported that loss of fat-free mass (FFM), measured by dual X-ray absorptiometry (DXA) is associated with loss of bone mineral density (BMD). In addition, in patients with a low body mass index (BMI) and a low FFM, all had evidence of bone thinning, 50% having osteopenia and 50% osteoporosis. We explored the utility of different anthropometric measures in detecting osteoporosis in a community-based COPD population. METHODS: Patients with confirmed COPD and not on long-term oral corticosteroids (n=58) performed spirometry. They underwent nutritional assessment by skinfold anthropometry, midarm circumference, calculation of both % ideal body weight (IBW) and BMI. All had DXA assessment of BMD. RESULTS: A total of 58 COPD patients had anthropometric measurements taken, with a mean age of 66.8 (SD 8.7) years, 31 (58%) were male, with a forced expiratory volume in 1s (FEV(1)) of 54.17 (20.18)% predicted. Osteoporosis was present at either the hip or lumbar region in 14 patients (24%). The useful anthropometric measurements identifying those with osteoporosis were both % IBW and BMI. The adjusted odds ratio for %IBW was 0.93 (95% confidence interval (CI) 0.87, 0.99), p=0.016 and for BMI: 0.79 (0.64-0.98), p=0.03. The receiver operating characteristics (ROC) score for both was 0.88, indicating a good fit. CONCLUSION: Osteoporosis is common, even in patients with mild airways obstruction. Nutritional assessment, incorporating a calculation of their BMI or %IBW may confer an additional benefit in detecting those at risk of osteoporosis and guide referral for BMD measurement.


Assuntos
Osteoporose/diagnóstico , Doença Pulmonar Obstrutiva Crônica/complicações , Absorciometria de Fóton , Idoso , Índice de Massa Corporal , Peso Corporal , Densidade Óssea , Feminino , Antebraço/anatomia & histologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Curva ROC , Dobras Cutâneas , Espirometria
13.
Ann Hum Biol ; 33(3): 357-71, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17092872

RESUMO

OBJECTIVE: The study examined the degree to which male and female survivors of acute lymphoblastic leukaemia (ALL) perceive effort at low and moderate intensity exercise in association with related physiological variables. MATERIALS AND METHODS: Participants were 67 children. Thirty-five (14 boys and 21 girls) were long-time survivors of ALL and 32 (18 boys and 14 girls) were control subjects. The Children's Effort Rating Table (CERT) was used to measure whole-body perceived exertion at low and moderate intensity exercise. Peak oxygen uptake was measured using a motorized treadmill. CERT and physiological data were analysed using 2 x 2 mixed analyses of variance, appropriate t-tests and coefficients of correlation. RESULTS: In absolute terms, boys treated for ALL found perception of effort to be more strenuous at both low (3.9 vs. 3.5 units) and moderate (6.1 vs. 5.3 units) intensity exercise than control subjects, although differences were not significant (p > 0.05); girls treated for ALL found perception of effort to be the same as controls at low intensity exercise (3.1 vs. 3.1 units) but slightly higher than controls at moderate intensity exercise (5.6 vs. 5.2 units); neither of these differences were significant (p > 0.05). When CERT values were adjusted for (.-)VO(2) peak (%) and heart rate (HR) peak (%) differences remained non-significant. There were no significant interactions (Intensity x Group) in males, but the interaction for (.-)VO(2) peak (%) was significant in females (p < 0.05). The main effect for Intensity (low and moderate) was significant for all variables in boys and girls (p < 0.0001). The main effect for Group (ALL and controls) identified significantly greater absolute (b.p.m.) and relative (%) HR values in ALL boys at low and moderate intensity exercise. In female ALL and control subjects the interaction (Intensity x Group) distinguished between (.-)VO(2) peak (%) at moderate intensity exercise and HR peak (%) at low and moderate intensity exercise. Coefficients of correlation between perceived effort and (.-)VO(2) peak (%) in boys and girls were low to high (0.28-0.76), and between absolute and relative HR were also low to high (0.33-0.73). There were low correlations between time 'off therapy' and perceived effort, (.-)VO(2) peak (%) and HR peak (%) (-0.003 to -0.49). CONCLUSION: It was concluded that perception of effort in survivors of ALL at low and moderate intensity exercise was the same as that of control subjects. Correlations between perceived effort and physiological variables at moderate exercise were low to high, while those between perceived effort and time from treatment were generally weak.


Assuntos
Esforço Físico/fisiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/fisiopatologia , Análise de Variância , Estudos de Casos e Controles , Criança , Estudos Transversais , Teste de Esforço , Tolerância ao Exercício/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
14.
Ergonomics ; 48(11-14): 1462-72, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16338713

RESUMO

The purpose of the present study was to ascertain whether differences existed in the regional placement of bone mineral mass (BMM), fat mass (FM) and lean soft tissue mass (LSTM) between playing units in Rugby Union Football and between players and control subjects. Thirty young adult rugby players and 21 controls participated in the study. Players were assigned to groups as either forwards (n = 15) or backs (n = 15). Control subjects were matched (n = 15) to rugby players using the mean BMI of forwards and backs. BMM, FM and LSTM were measured using dual-energy X-ray absorptiometry. The digital image of each subject was partitioned into regional anatomical segments comprising the head, right and left arms, trunk, and right and left legs. Measurements were summed for the arms and legs respectively. One-way ANOVA was used to differentiate between- and within-groups; Tukey's post-hoc test was applied to identify pairwise differences. The alpha level was set throughout at p = 0.01. Principal components analysis was utilized to contrast the regional segments of each tissue in each of the groups. Forwards exhibited larger absolute (kg) amounts of BMM, FM and LSTM than backs or controls. In relative terms (%) there were no significant differences in BMM(%) between forwards, backs and controls in the arms and legs, but differences did occur between backs and controls at the trunk (2.9 vs. 2.5%). Backs had a significantly larger LSTM(%) than forwards at the arms (84.4 vs. 76.5%), legs (80.0 vs. 71.9%) and trunk (89.2 vs. 79.0%), whereas forwards had a greater FM(%) than backs at the arms (18.7 vs. 10.6%), legs (23.1 vs. 14.7%), and trunk (18.4 vs. 8.0%). The distribution of BMM showed a lower body-upper body contrast in forwards, a trunk-extremity contrast in backs and an arm-lower body contrast in controls. FM exhibited a trunk-extremity contrast in all three groups, while LSTM displayed an arm-lower body contrast in all three groups. It is concluded that there are significant regional tissue differences between forwards and backs, which may be related to playing function, and also differences between rugby players and controls.


Assuntos
Distribuição da Gordura Corporal , Densidade Óssea , Futebol Americano/fisiologia , Absorciometria de Fóton , Adulto , Antropometria , Composição Corporal , Índice de Massa Corporal , Humanos , Masculino
15.
Technol Health Care ; 13(2): 75-85, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15912005

RESUMO

It has been suggested that quantitative ultrasound (QUS) could be used as a selective population pre-screen, to maximise the cost effectiveness of referral for dual energy X-ray absorptiometry (DXA) assessment of bone mineral density (BMD). We set out to examine how such an approach might perform in the assessment of women who were referred by general practitioners for DXA via the open access service in Cardiff. In 115 women aged 40-80 (mean 69) years we used DXA to measure BMD at lumbar spine and hip, and QUS to measure broadband ultrasound attenuation (BUA) in the heel. A bottom-up approach was used to estimate the costs of DXA and QUS. We examined the cost effectiveness of using QUS as a pre-screen, only referring subjects for the more expensive DXA assessment if BUA were less than a pre-determined threshold. The unit costs of pencil-beam DXA and QUS were approximately 44 UK pounds and 16 UK pounds respectively. We identified a BUA threshold of 60 dB/MHz as the most cost effective, and calculated a sensitivity of 81% and specificity of 89% in identifying those subjects whom DXA assessment subsequently identified as having osteoporosis. At the BUA threshold of 60 dB/MHz, pre-screening saved 969 UK pounds at the expense of missing ten women with osteoporosis as diagnosed by DXA. Therefore the cost per additional woman with osteoporosis identified using DXA alone was only 97 UK pounds. QUS assessment does not appear to have a significant cost effective benefit as a pre-screen for DXA in the studied population. A QUS pre-screen would be cost effective only if this investigation could be performed at a substantially lower cost.


Assuntos
Absorciometria de Fóton/estatística & dados numéricos , Calcanhar/diagnóstico por imagem , Quadril/diagnóstico por imagem , Região Lombossacral/diagnóstico por imagem , Programas de Rastreamento/métodos , Osteoporose/diagnóstico por imagem , Medicina Estatal/economia , Absorciometria de Fóton/economia , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Análise Custo-Benefício , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Programas de Rastreamento/economia , Pessoa de Meia-Idade , Curva ROC , Encaminhamento e Consulta , Avaliação da Tecnologia Biomédica , Ultrassonografia , País de Gales
16.
Arch Orthop Trauma Surg ; 125(5): 348-54, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15843946

RESUMO

INTRODUCTION: Venous compression of the lower limbs will obstruct outflow through the deep and superficial veins, yet inflow will continue, without continual swelling of the limb. It is hypothesised that venous channels in the long bones act as collateral channels to restore outflow, and therefore general blood flow through bone will increase. Such a hemodynamic change should affect the uptake of radiopharmaceuticals by the bone, though uptake changes in themselves would not definitely indicate flow changes. The purpose of this study, therefore, was to determine whether bone uptake in the lower limb is affected by intermittent venous compression, irrespective of the mechanism involved. MATERIALS AND METHODS: The effect of intermittent pneumatic compression of the thigh and calf on the uptake of (99m)Tc-methylene diphosphonate (MDP) was studied in 24 patients. All were undergoing routine bone imaging for medical conditions that were not focused on their lower limbs, and received 1 h of the therapy at 60 mmHg on one limb only, after injection of the radiopharmaceutical. Three hours after injection the relative difference in uptake (net counts per pixel) between the two limbs was calculated. The standard imaging protocol was otherwise unchanged. RESULTS: The median differences in uptake in the intermittently compressed limb compared with the contralateral limb were +7.6% (interquartile range +3.9% to +16.0%, p<0.0005 [Wilcoxon]) for the anterior aspect of the femur; +11.7% (interquartile range +4.3% to +22.2%, p<0.0005) posterior, femur; +10.5% (interquartile range +6.5% to +13.8%, p<0.0005) anterior, tibia; +10.6% (interquartile range +5.5% to +17.6%, p<0.0005) posterior, tibia. CONCLUSION: Intermittent pneumatic compression clearly and significantly increased the uptake of (99m)Tc-MDP in long bones. These data are consistent with increases in blood flow through bone, though a direct mechanical influence on the bone cannot be excluded. This effect should be given consideration during routine therapeutic and thromboprophylactic use of intermittent compression, and if the mechanism of the uptake changes can be established, their possible clinical uses should be investigated.


Assuntos
Bandagens , Fêmur/irrigação sanguínea , Compostos Radiofarmacêuticos/farmacocinética , Medronato de Tecnécio Tc 99m/farmacocinética , Tíbia/irrigação sanguínea , Adulto , Feminino , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Humanos , Extremidade Inferior , Masculino , Pressão , Cintilografia , Fluxo Sanguíneo Regional/fisiologia , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos
17.
Am J Hum Biol ; 16(5): 533-43, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15368601

RESUMO

The purpose of the present study was to identify the effect of treatment with recombinant human growth hormone (rhGH) on seven somatic characteristics and eight clinical cardiovascular risk factors. Twenty-seven male and 24 female patients between the ages of 21 and 60 years were examined. The investigation was a double-blind, placebo-controlled study of 12 months duration. Patients were assigned randomly to treatment (T) and placebo (P) groups. In the first 6 months group T received rhGH and group P placebo. In the second 6 months both groups received rhGH. Complete data were available for 23 males and 20 females. Increments were calculated between 6 months -BL (increment 1) and 12-6 months (increment 2) in both T and P groups. Apart from the somatotype, data were analysed with a 2 x 2 mixed analysis of variance (ANOVA) using treatment (rhGH and placebo) and time (increments 1 and 2). Somatotype data were analysed using a 2 x 3 multivariate ANOVA. Three significant interactions were identified in males: waist circumference (P = 0.006), trunk fat (P = 0.0001), and conicity index (P = 0.001). The only significant interaction in females was trunk fat (P = 0.006). In general, treatment and placebo groups responded differently by time and treatment. Responses were similar in males and females. In the first 6 months when group P was on placebo, waist circumference, trunk fat, and conicity index increased slightly; with group T on rhGH somatic variables declined markedly. In the second 6 months when both groups received rhGH there was a marked decline in group P and a continued decline (but less steeply) in group T. In males there were significant decreases in endomorphy in group T and increases in mesomorphy in group P. In females the somatotype remained stable. There were no significant interactions in clinical cardiovascular risk factors in either males or females. Favourable responses occurred in male and female lipid profiles, although these were not significant. It was concluded that in males waist circumference, trunk fat, conicity index, and somatotype responded significantly to treatment with rhGH; in females the only significant response was trunk fat.


Assuntos
Composição Corporal/efeitos dos fármacos , Doenças Cardiovasculares/prevenção & controle , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/uso terapêutico , Adulto , Distribuição por Idade , Antropometria , Estatura/efeitos dos fármacos , Doenças Cardiovasculares/epidemiologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Seguimentos , Transtornos do Crescimento/diagnóstico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Probabilidade , Valores de Referência , Medição de Risco , Fatores de Risco , Distribuição por Sexo , Resultado do Tratamento
18.
Int J Clin Pract ; 58(3): 300-5, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15117100

RESUMO

General practitioners (GPs) are increasingly involved in the selective opportunistic case finding of osteoporosis and treatment of this condition. An open access bone densitometry service has existed for GPs in the Cardiff area since 1993. The purpose of this study was to assess the effectiveness of this service, particularly with respect to the appropriateness of bone densitometry requests and the impact of the service on hospital outpatient referrals. Over a period of 12 months, 560 patients were referred to the open access service by 154 GPs. A total of 229 (41%) patients were given a clinical diagnosis of osteoporosis. Four hundred and seventy-three (84%) referrals followed the clinical referral criteria. In 85% of cases, GPs claimed that they would have referred patients to the hospital outpatient department, if there were no open access bone densitometry service. The majority of the referrals were appropriate, and the service appears to have reduced GP referrals to the specialist clinic.


Assuntos
Medicina de Família e Comunidade/organização & administração , Acessibilidade aos Serviços de Saúde/organização & administração , Osteoporose/diagnóstico , Absorciometria de Fóton , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , País de Gales
19.
Clin Endocrinol (Oxf) ; 60(3): 358-65, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15009002

RESUMO

OBJECTIVE: Osteopenia and excess adiposity occur following treatment of childhood acute lymphoblastic leukaemia (ALL) and the use of cranial irradiation is thought to be a significant contributory factor. Hyperleptinaemia has also been demonstrated following cessation of treatment for childhood ALL. Therefore a prospective study was undertaken to evaluate serial changes in percentage bone mineral content (BMC), adiposity and serum leptin concentrations during 2 years of treatment of children with ALL with chemotherapy but without cranial irradiation. DESIGN AND PATIENT: Only patients treated using the MRC ALL 97/ALL 97 (modified 99) protocols for childhood ALL were eligible for entry into the study. A total of 14 patients (seven male, with a median age of 7.5 years (range 3.4-16.7 years) were recruited. Serial dual energy X-ray absorptiometry (DEXA) scanning was undertaken at diagnosis and during two years of treatment. Serum leptin concentrations were determined at the same time as the scans. RESULTS: Reductions in %BMC were observed at the hip and lumbar spine by 12 months (P < 0.01) and remained low after 24 months of treatment. Subanalysis of %BMC measurements at the hip demonstrated a greater reduction in %BMC at the trochanteric region compared to the femoral neck. The percentage corrected fat mass increased from 6 months whereas the body mass index (BMI) standard deviation score (SDS) was increased after 24 months of treatment (P < 0.05). Serum leptin concentrations increased following 24 months of therapy (P < 0.05). CONCLUSIONS: Children treated for ALL with contemporary regimens have a predisposition to osteopenia, excess adiposity and hyperleptinaemia during treatment without cranial irradiation administration. We speculate that in addition to glucocorticoid administration, leptin resistance may account in part for these observations.


Assuntos
Doenças Ósseas Metabólicas/complicações , Leptina/sangue , Obesidade/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Doenças Ósseas Metabólicas/metabolismo , Doenças Ósseas Metabólicas/patologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Obesidade/metabolismo , Obesidade/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Estudos Prospectivos
20.
Arch Dis Child ; 89(1): 64-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14709512

RESUMO

BACKGROUND: Body fat mass (FM) and fat free mass (FFM) in childhood are often estimated by conversion of a measured variable into compartmental body composition using constants or regression equations that have been previously derived in healthy individuals. Application of such constants or equations to children with disease states may lead to inappropriate conclusions since the "normal" relationships may become altered. AIMS AND METHODS: To test this hypothesis by taking measurements of body composition using dual energy x ray absorptiometry (DEXA) as a "gold standard" method and calculating hydration and body potassium constants using isotopic water dilution and whole body potassium counting. Measurements of bioelectrical impedance (BIA) by two different analysers (RJL and Holtain) were also performed to allow comparison with body water measurements. RESULTS: Measurements were performed in 35 children treated for acute lymphoblastic leukaemia (ALL) and compared to those in 21 children treated for a variety of other malignancies and 32 healthy sibling controls. The mean hydration and potassium content of FFM was significantly reduced in the ALL group compared to both other malignancies and controls. Application of equations derived from controls for the measurement of FFM derived from bioelectrical impedance led to an underestimation of 1.15 kg when compared to that derived from DEXA in children treated for ALL but not in other malignancies. For all groups combined, BIA was significantly different in the two analysers. CONCLUSION: Care needs to be taken in the application of equations derived from the normal population to body composition measurement in children treated for ALL.


Assuntos
Composição Corporal , Leucemia-Linfoma Linfoblástico de Células Precursoras/fisiopatologia , Absorciometria de Fóton , Tecido Adiposo/química , Índice de Massa Corporal , Água Corporal/química , Criança , Estudos de Coortes , Impedância Elétrica , Humanos , Potássio/análise , Sobreviventes
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