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1.
J Thromb Haemost ; 18(4): 905-915, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31995662

RESUMO

BACKGROUND: The Anticoagulation Therapy in Selected Cancer Patients at Risk of Recurrence of Venous Thromboembolism (SELECT-D) trial demonstrated reduction in recurrent venous thromboembolism (VTE) but increased bleeding with rivaroxaban compared with dalteparin for treatment of acute VTE in cancer patients, at 6 months. Uncertainty remains around optimal duration of anticoagulation. OBJECTIVES: To assess VTE recurrence and bleeding, with anticoagulation or not, beyond 6 months. PATIENTS/METHODS: In SELECT-D, after 6 months of trial treatment for VTE, patients with active cancer and residual deep vein thrombosis (RDVT) or index pulmonary embolism (PE) were eligible for randomization to a further 6 months of rivaroxaban or placebo. Patients with no RDVT stopped anticoagulation. Primary outcome was VTE recurrence at 12 months. The second randomization closed prematurely because of low recruitment when 92 of the planned 300 patients were recruited. RESULTS: Ninety-two of 136 eligible patients were randomized to rivaroxaban or placebo. The cumulative VTE recurrence after 6 months from the second randomization was 14% with placebo and 4% with rivaroxaban (hazard ratio, 0.32; 95% confidence interval [CI], 0.06-1.58). The major and clinically relevant non-major bleeding rates were 0% and 0% with placebo; and 5% (95% CI, 1-18) and 4% (95% CI, 1-17) with rivaroxaban. In an exploratory analysis, 7 (15%) of 46 placebo patients with RDVT or an index PE experienced recurrent VTE compared to none in the 35 patients in the RDVT-negative cohort (P = .03). CONCLUSION: The SELECT-D trial was underpowered to detect a statistically significant reduction in recurrent VTE with extended anticoagulation. The absence of RDVT and/or index PE, defined a population at low risk of recurrence.


Assuntos
Neoplasias , Tromboembolia Venosa , Anticoagulantes/efeitos adversos , Humanos , Neoplasias/complicações , Distribuição Aleatória , Rivaroxabana/efeitos adversos , Resultado do Tratamento , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/tratamento farmacológico
2.
Hum Mov Sci ; 45: 154-60, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26638048

RESUMO

Considerable evidence supports the motor learning advantage associated with an external focus of attention; however, very few studies have investigated attentional focus effects with children despite individual functional constraints that have the potential to impact use of instructional content. Thus, the purpose of this study was to determine the effect of attentional focus instruction on motor learning in children. Participants (n=42) aged 9-11years were randomly assigned to one of three gender-stratified groups: (1) control, (2) internal focus, or (3) external focus. Following initial instructions and task demonstration, participants performed 100 modified free throws over two days while receiving additional cues respective to their attentional focus condition and returned approximately 48h later to perform 20 additional free throws. Results revealed no significant learning differences between groups. However, responses to retrospective verbal reports suggest that the use of external focus content during practice may have contributed to some participants' superior performance in retention. Future research should continue to examine attentional focus effects across a variety of ages and incorporate retrospective verbal reports in order to examine children's thoughts during attentional focus instruction.


Assuntos
Atenção , Controle Interno-Externo , Desempenho Psicomotor , Pensamento , Criança , Sinais (Psicologia) , Feminino , Humanos , Conhecimento Psicológico de Resultados , Masculino , Aparelhos Ortopédicos , Prática Psicológica , Estudos Retrospectivos
3.
Res Q Exerc Sport ; 86(4): 422-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26230869

RESUMO

PURPOSE: Considerable research supports the motor-learning advantage associated with an external focus of attention; however, very few studies have attempted to generalize these findings to children especially with attentional focus feedback. Therefore, the purpose of this study was to determine the effect of attentional focus feedback on motor learning in children. METHOD: Boys (n = 14) and girls (n = 14) aged 9 to 11 years old were randomly assigned to 1 of 2 gender-stratified groups: (a) internal-focus feedback or (b) external-focus feedback. Following initial instructions and task demonstration, participants performed 100 modified free throws over 2 days while receiving feedback statements respective to their attentional focus condition. Approximately 24 hr later, participants performed a retention test consisting of 20 additional free throws. Participants were also asked to respond to a retrospective verbal report at the end of each day to serve as a manipulation check. RESULTS: Results of the analysis revealed a statistically significant learning advantage for participants receiving external-focus feedback, and retrospective verbal reports provide support for the self-invoking trigger and constrained action hypotheses. CONCLUSIONS: Future research should continue to incorporate retrospective verbal reports and explore potential causal links between internal attentional focus and self-evaluation.


Assuntos
Atenção , Retroalimentação Psicológica , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos
4.
Lancet ; 385 Suppl 1: S81, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26312903

RESUMO

BACKGROUND: Preterm infants are at increased risk of cardiometabolic disease in later life. Extrauterine growth restriction, catch-up growth, altered adiposity, and abnormal hypothalamic-pituitary-adrenal axis activity could be predisposing factors. Altered DNA methylation (5-methylcytosine, 5mC) might be one underlying mechanism. We hypothesised that preterm infants have altered 5mC at the linked differentially methylated region 2 (DMR2) of IGF2 and the H19 imprinting control region (H19 ICR) compared with term infants over the first year of life. METHODS: We recruited 46 preterm (range 25 weeks + 2 days' gestation to 31 + 5, mean 28 + 6) and 40 term infants (38 + 3 to 42 + 2 weeks' gestation, mean 40 + 2). Anthropometric variables including body composition were measured at term age and 3 months corrected age with air displacement plethysmography and at 1-year-corrected age with skin-fold thickness. Salivary cortisol was measured at 3 months corrected age after the physical examination. Percentage methylation (%5mC) was analysed with pyrosequencing on buccal DNA. Statistical analysis used Student's t test and multivariate linear regression. FINDINGS: Preterm infants demonstrated growth deficit early in postnatal life but had greater percentage body fat at term age (ß=5·73, p<0·001), but not at 3 months (ß=-0·28, p=0·82). Compared with term infants, preterm infants had a blunted cortisol response to physical examination (mean difference 0·38 µg/dL, p=0·024). At birth, preterm infants had a significant decrease in %5mC at DMR2 compared with term infants at birth (ß=-11·48, p<0·001) and compared with preterm infants at term-corrected age (t=3·13, p=0·01). By term-corrected age, preterm infants had decreased %5mC at both DMR2 (ß=-2·84, p=0·013) and the H19 ICR (ß=-2·31, p=0·048) compared with term infants at birth, although this difference disappeared at 1 year. Social deprivation was independently associated with decreased %5mC at DMR2 at birth (ß=-1·73, p=0·006) and term-corrected age (ß=-0·86, p=0·016) but not at 1 year (ß=-0·89, p=0·07). INTERPRETATION: Our results show that decreased %5mC accompanies the early growth deficit in preterm infants. The marked reduction in %5mC at IGF2 DMR2 in preterm infants at birth compared with term-age supports existing evidence that imprinting at secondary regions is established after fertilisation, whereas imprinting is established during gametogenesis at primary regions (H19 ICR). Both regions might be susceptible to early life stressors such as preterm birth and social deprivation. FUNDING: Chief Scientist Office of the Scottish Government.

5.
Ophthalmic Physiol Opt ; 35(5): 577-81, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26088949

RESUMO

PURPOSE: To establish the safety of the CHANGES glaucoma referral refinement scheme (GRRS). METHODS: The CHANGES scheme risk stratifies glaucoma referrals, with low risk referrals seen by a community based specialist optometrist (OSI) while high risk referrals are referred directly to the hospital. In this study, those patients discharged by the OSI were reviewed by the consultant ophthalmologist to establish a 'false negative' rate (Study 1). Virtual review of optic disc photographs was carried out both by a hospital-based specialist optometrist as well as the consultant ophthalmologist (Study 2). RESULTS: None of these 34 discharged patients seen by the consultant were found to have glaucoma or started on treatment to lower the intra-ocular pressure. Five of the 34 (15%) were classified as 'glaucoma suspect' based on the appearance of the optic disc and offered a follow-up appointment. Virtual review by both the consultant and optometrist had a sensitivity of 80%, whilst the false positive rate for the optometrist was 3.4%, and 32% for the consultant (p < 0.05). CONCLUSIONS: The false negative rate of the OSIs in the CHANGES scheme was 15%, however there were no patients where glaucoma was missed. Virtual review in experienced hands can be as effective as clinical review by a consultant, and is a valid method to ensure glaucoma is not missed in GRRS. The CHANGES scheme, which includes virtual review, is effective at reducing referrals to the hospital whilst not compromising patient safety.


Assuntos
Glaucoma/diagnóstico , Optometria/normas , Seleção Visual/normas , Adulto , Idoso , Reações Falso-Negativas , Feminino , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/diagnóstico , Encaminhamento e Consulta/normas , Tonometria Ocular , Reino Unido , Testes de Campo Visual , Campos Visuais
6.
Int J Comput Assist Radiol Surg ; 10(10): 1639-50, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25700699

RESUMO

PURPOSE: A methodological framework is introduced to assess and compare a conventional fluoroscopy protocol for peripheral angioplasty with a new magnetic resonant imaging (MRI)-guided protocol. Different scenarios were considered during interventions on a perfused arterial phantom with regard to time-based and cognitive task analysis, user experience and ergonomics. METHODS: Three clinicians with different expertise performed a total of 43 simulated common iliac angioplasties (9 fluoroscopic, 34 MRI-guided) in two blocks of sessions. Six different configurations for MRI guidance were tested in the first block. Four of them were evaluated in the second block and compared to the fluoroscopy protocol. Relevant stages' durations were collected, and interventions were audio-visually recorded from different perspectives. A cued retrospective protocol analysis (CRPA) was undertaken, including personal interviews. In addition, ergonomic constraints in the MRI suite were evaluated. RESULTS: Significant differences were found when comparing the performance between MRI configurations versus fluoroscopy. Two configurations [with times of 8.56 (0.64) and 9.48 (1.13) min] led to reduce procedure time for MRI guidance, comparable to fluoroscopy [8.49 (0.75) min]. The CRPA pointed out the main influential factors for clinical procedure performance. The ergonomic analysis quantified musculoskeletal risks for interventional radiologists when utilising MRI. Several alternatives were suggested to prevent potential low-back injuries. CONCLUSIONS: This work presents a step towards the implementation of efficient operational protocols for MRI-guided procedures based on an integral and multidisciplinary framework, applicable to the assessment of current vascular protocols. The use of first-user perspective raises the possibility of establishing new forms of clinical training and education.


Assuntos
Angioplastia/métodos , Fluoroscopia/métodos , Aneurisma Ilíaco/cirurgia , Imageamento por Ressonância Magnética/métodos , Cirurgia Assistida por Computador/métodos , Simulação por Computador , Ergonomia , Humanos , Estudos Retrospectivos , Fluxo de Trabalho
7.
Ophthalmic Physiol Opt ; 33(2): 183-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23406492

RESUMO

PURPOSE: To assess the impact of referral refinement criteria on the number of patients referred to, and first-visit discharges from, the Hospital Eye Service (HES) in relation to the National Institute for Health & Clinical Excellence (NICE) Glaucoma Guidelines, Joint College Group Guidance (JCG) and the NICE commissioning guidance. METHODS: All low-risk (one risk factor: suspicious optic disc, abnormal visual field (VF), raised intra-ocular pressure (IOP) (22-28 mmHg) or IOP asymmetry (>5 mmHg) and high-risk (more than one risk factor, shallow anterior chamber or IOP >28 mmHg) referrals to the HES from 2006 to 2011 were analysed. Low-risk referrals were seen by Optometrists with a specialist interest in glaucoma and high-risk referrals were referred directly to the HES. RESULTS: Two thousand nine hundred and twelve patient records were analysed. The highest Consultant first-visit discharge rates were for referrals based on IOP alone (45% for IOP 22-28 mmHg) and IOP asymmetry (53%), VF defect alone (46%) and for abnormal IOP and VF (54%). The lowest first-visit discharge rates were for referrals for suspicious optic disc (19%) and IOP >28 mmHg (22%). 73% of patients aged 65-80 and 60% of patients aged >80 who were referred by the OSI due to an IOP between 22-28 mmHg would have satisfied the JCG criteria for non-referral. For patients referred with an IOP >28 mmHg and an otherwise normal examination, adherence to the NICE commissioning guidance would have resulted in 6% fewer referrals. In 2010 this scheme reduced the number of patients attending the HES by 15%, which resulted in a saving of £16 258 (13%). CONCLUSION: The results support that referrals for a raised IOP alone or in combination with an abnormal VF be classified as low-risk and undergo referral refinement. Adherence to the JCG and the NICE commissioning guidance as onward referral criteria for specialist optometrists in this referral refinement scheme would result in fewer referrals.


Assuntos
Glaucoma/diagnóstico , Optometria/normas , Ambulatório Hospitalar/estatística & dados numéricos , Alta do Paciente/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Encaminhamento e Consulta/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Reino Unido
8.
Br J Ophthalmol ; 97(2): 210-4, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23111242

RESUMO

AIM: To investigate whether the publication of the National Institute for Health and Clinical Excellence (NICE) glaucoma guidelines had an effect on the agreement of examination findings between professionals involved in an established glaucoma referral refinement pathway. METHODS: To report inter-professional agreement for the clinical examination findings of optometrists with a special interest in glaucoma (OSI), optometrists with no specialist interest in glaucoma (non-OSI) and a glaucoma consultant. Part 1 investigated agreement between an OSI and consultant and part 2 investigated agreement of clinical findings between the non-OSI and a specialist clinician (OSI or consultant). RESULTS: Part 1: Agreement between OSI and consultant in determining an abnormal intraocular pressure (IOP) (>21 mm Hg) expressed as a percentage positive predictive value (PPPV) was no different pre-NICE (60.6%) and post-NICE (61.4%, p=0.51) guidelines. PPPV for identification of an abnormal optic disc was better pre-NICE (60.6%) than post-NICE (42.7%, p=0.02). The appropriate referral rate for patients referred by an OSI was higher pre-NICE (69.6%) than post-NICE (61.2%) (p=0.07). Part 2: The PPPV between non-OSI and specialist clinician for an abnormal IOP was better pre-NICE (62.5%) than post-NICE (50.9%, p=0.12). This was also observed for abnormal optic discs, 70.0% pre-NICE and 52.9% post-NICE (p=0.04). CONCLUSIONS: The accuracy for detecting an abnormal IOP by the OSI has remained unchanged post-NICE, but there was a reduction in accuracy in detecting an abnormal optic disc as well as the appropriate referral rate. For the non-OSI, there was a decline in both IOP and optic disc assessment accuracy.


Assuntos
Competência Clínica/normas , Glaucoma/diagnóstico , Educação em Saúde/normas , Pressão Intraocular , Optometria/normas , Guias de Prática Clínica como Assunto , Encaminhamento e Consulta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Reino Unido
9.
J Athl Train ; 45(3): 287-98, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20446843

RESUMO

CONTEXT: Organizational effectiveness and the continuity of patient care can be affected by certain levels of attrition. However, little is known about the retention and attrition of female certified athletic trainers (ATs) in certain settings. OBJECTIVE: To gain insight and understanding into the factors and circumstances affecting female ATs' decisions to persist in or leave the National Collegiate Athletic Association Division I Football Bowl Subdivision (NCAA D-I FBS) setting. DESIGN: Qualitative study. SETTING: The 12 NCAA D-I FBS institutions within the Southeastern Conference. PATIENTS OR OTHER PARTICIPANTS: A total of 23 women who were current full-time ATs (n = 12) or former full-time ATs (n = 11) at Southeastern Conference institutions participated. DATA COLLECTION AND ANALYSIS: Data were collected via in-depth, semistructured interviews, transcribed verbatim, and analyzed via a grounded theory approach. Peer review and member checking methods were performed to establish trustworthiness. RESULTS: The decision to persist involved 4 main factors: (1) increased autonomy, (2) increased social support, (3) enjoyment of job/fitting the NCAA D-I mold, and (4) kinship responsibility. Two subfactors of persistence, the NCAA D-I atmosphere and positive athlete dynamics, emerged under the main factor of enjoyment of job/fitting the NCAA D-I mold. The decision to leave included 3 main factors: (1) life balance issues, (2) role conflict and role overload, and (3) kinship responsibility. Two subfactors of leaving, supervisory/coach conflict and decreased autonomy, emerged under the main factor of role conflict and role overload. CONCLUSIONS: A female AT's decision to persist in or leave the NCAA D-I FBS setting can involve several factors. In order to retain capable ATs long term in the NCAA D-I setting, an individual's attributes and obligations, the setting's cultural issues, and an organization's social support paradigm should be considered.


Assuntos
Traumatismos em Atletas , Esgotamento Profissional , Futebol Americano/lesões , Reorganização de Recursos Humanos/estatística & dados numéricos , Medicina Esportiva , Adulto , Continuidade da Assistência ao Paciente , Eficiência Organizacional , Feminino , Grupos Focais , Humanos , Satisfação no Emprego , Pessoa de Meia-Idade , Pesquisa Qualitativa , Apoio Social , Medicina Esportiva/estatística & dados numéricos , Estresse Psicológico , Estados Unidos , Recursos Humanos
10.
Eur J Neurosci ; 30(2): 299-306, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19614978

RESUMO

The 5-HT(2C) receptor has been implicated in mood and eating disorders. In general, it is accepted that 5-HT(2C) receptor agonists increase anxiety behaviours and induce hypophagia. However, pharmacological analysis of the roles of these receptors is hampered by the lack of selective ligands and the complex regulation of receptor isoforms and expression levels. Therefore, the exact role of 5-HT(2C) receptors in mood disorders remain controversial, some suggesting agonists and others suggesting antagonists may be efficacious antidepressants, while there is general agreement that antagonists are beneficial anxiolytics. In order to test the hypothesis that increased 5-HT(2C) receptor expression, and thus increased 5-HT(2C) receptor signalling, is causative in mood disorders, we have undertaken a transgenic approach, directly altering the 5-HT(2C) receptor number in the forebrain and evaluating the consequences on behaviour. Transgenic mice overexpressing 5-HT(2C) receptors under the control of the CaMKIIalpha promoter (C2CR mice) have elevated 5-HT(2C) receptor mRNA levels in cerebral cortex and limbic areas (including the hippocampus and amygdala), but normal levels in the hypothalamus, resulting in > 100% increase in the number of 5-HT(2C) ligand binding sites in the forebrain. The C2CR mice show increased anxiety-like behaviour in the elevated plus-maze, decreased wheel-running behaviour and reduced activity in a novel environment. These behaviours were observed in the C2CR mice without stimulation by exogenous ligands. Our findings support a role for 5-HT(2C) receptor signalling in anxiety disorders. The C2CR mouse model offers a novel and effective approach for studying disorders associated with 5-HT(2C) receptors.


Assuntos
Ansiedade/metabolismo , Expressão Gênica , Atividade Motora/fisiologia , Prosencéfalo/fisiologia , Receptor 5-HT2C de Serotonina/biossíntese , Animais , Ansiedade/genética , Células COS , Chlorocebus aethiops , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Ratos , Receptor 5-HT2C de Serotonina/genética
11.
Br J Haematol ; 146(2): 185-92, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19438469

RESUMO

Circadian (c. 24 h) rhythms of physiology are entrained to either the environmental light-dark cycle or the timing of food intake. In the current work the hypothesis that rhythms of platelet turnover in mammals are circadian and entrained by food intake was explored in mice. Mice were entrained to 12 h light-dark cycles and given either ad libitum (AL) or restricted access (RF) to food during the light phase. Blood and megakaryocytes were then collected from mice every 4 h for 24 h. It was found that total and reticulated platelet numbers, plasma thrombopoietin (TPO) concentration and the mean size of mature megakaryocytes were circadian but not entrained by food intake. In contrast, a circadian rhythm in the expression of Arnt1 in megakaryocytes was entrained by food. Although not circadian, the expression in megakaryocytes of Nfe2, Gata1, Itga2b and Tubb1 expression was downregulated by RF, whereas Ccnd1 was not significantly affected by the feeding protocol. It is concluded that circadian rhythms of total platelet number, reticulated platelet number and plasma TPO concentration are entrained by the light-dark cycle rather than the timing of food intake. These findings imply that circadian clock gene expression regulates platelet turnover in mammals.


Assuntos
Plaquetas/fisiologia , Ritmo Circadiano/fisiologia , Comportamento Alimentar/fisiologia , Megacariócitos/fisiologia , Estimulação Luminosa , Trombopoetina/metabolismo , Análise de Variância , Animais , Proteínas de Transporte/metabolismo , Ciclina D1/metabolismo , Proteínas Fetais/metabolismo , Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos , Contagem de Plaquetas , Trombopoese/fisiologia , Fatores de Tempo , Fatores de Transcrição/metabolismo , Tubulina (Proteína)/metabolismo
12.
Res Q Exerc Sport ; 78(3): 179-88, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17679491

RESUMO

The purpose of this study was to compare measures of body size in two samples of youth baseball players with normative data from the United States National Center for Health Statistics (NCHS) growth charts. One sample of youth baseball players participated in a local little league. The second sample of youth baseball players were members of eight of the twelve teams participating in the 1995 Dixie Youth World Series. Normative data for the United States (NCHS) were used as comparative data. Two trained anthropometrists measured standing height, sitting height, lower limb height, upper limb length, arm girth, calf girth, tricep skinfold, and abdomen skinfold on all participants. In both samples, pitchers, short stops, and first basemen were a more highly skilled group and exhibited larger body size (greater standing height, sitting height, lower limb height, upper limb length) than children who played at other positions. The standing height of local little league players was similar to the median of reference data at ages 7, 8, and 9 years. The standing height and weight of skilled players in both samples approximated the 75th percentile for standing height and weight at ages 10, 11, 12, and 13 years. The results suggest that baseball players exhibit larger body size than the normal population at young ages. Body size may be an important criterion used by coaches to select and assign young players to certain positions.


Assuntos
Antropometria , Beisebol , Antropometria/métodos , Criança , Estudos Transversais , Humanos , Estudos Longitudinais , South Carolina , Estados Unidos
13.
J Neurosci ; 27(16): 4351-8, 2007 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-17442819

RESUMO

The master clock driving mammalian circadian rhythms is located in the suprachiasmatic nuclei (SCN) of the hypothalamus and entrained by daily light/dark cycles. SCN lesions abolish circadian rhythms of behavior and result in a loss of synchronized circadian rhythms of clock gene expression in peripheral organs (e.g., the liver) and of hormone secretion (e.g., corticosterone). We examined rhythms of behavior, hepatic clock gene expression, and corticosterone secretion in VPAC2 receptor-null (Vipr2-/-) mice, which lack a functional SCN clock. Unexpectedly, although Vipr2-/- mice lacked robust circadian rhythms of wheel-running activity and corticosterone secretion, hepatic clock gene expression was strongly rhythmic, but advanced in phase compared with that in wild-type mice. The timing of food availability is thought to be an important entrainment signal for circadian clocks outside the SCN. Vipr2-/- mice consumed food significantly earlier in the 24 h cycle than wild-type mice, consistent with the observed timing of peripheral rhythms of circadian gene expression. When restricted to feeding only during the daytime (RF), mice develop rhythms of activity and of corticosterone secretion in anticipation of feeding time, thought to be driven by a food-entrainable circadian oscillator, located outside the SCN. Under RF, mice of both genotypes developed food-anticipatory rhythms of activity and corticosterone secretion, and hepatic gene expression rhythms also became synchronized to the RF stimulus. Thus, food intake is an effective zeitgeber capable of coordinating circadian rhythms of behavior, peripheral clock gene expression, and hormone secretion, even in the absence of a functional SCN clock.


Assuntos
Ritmo Circadiano/genética , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/fisiologia , Fígado/metabolismo , Receptores Tipo II de Peptídeo Intestinal Vasoativo/fisiologia , Animais , Corticosterona/metabolismo , Sinais (Psicologia) , Expressão Gênica , Luz , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Núcleo Supraquiasmático/fisiologia
14.
Percept Mot Skills ; 105(3 Pt 1): 883-90, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18229542

RESUMO

Manipulating the organization of practice conditions, through contextual interference, was identified as a method to promote motor skill acquisition by Brady in 1998. The generalizability of this learning effect is questionable and the amount of repetition versus the amount of change in task presentation requires investigation. The purpose of this study was to explore explanations for the performance of learners practicing the AAHPERD volleyball skills test when the change in task presentation varied. High school students were randomly assigned to blocked, random, and random-blocked practice groups. While all groups significantly improved all skills during acquisition, there was no support for the contextual interference effect. Potential explanations might be dependent upon the learners' skill and the complexity of the task to be learned. Further research is warranted examining contextual interference effect on practice organization at levels of difficulty appropriate to facilitate cognitive processing of task-related information.


Assuntos
Desempenho Atlético/fisiologia , Destreza Motora/fisiologia , Prática Psicológica , Retenção Psicológica/fisiologia , Voleibol/fisiologia , Logro , Adolescente , Desempenho Atlético/psicologia , Feminino , Humanos , Masculino , Movimento/fisiologia , Educação Física e Treinamento/métodos , Análise e Desempenho de Tarefas , Ensino , Voleibol/psicologia
15.
J Neurosci ; 26(14): 3840-4, 2006 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-16597738

RESUMO

Low birth weight associates with increased susceptibility to adult cardiometabolic and affective disorders spawning the notion of fetal "programming." Prenatal exposure to excess glucocorticoids may be causal. In support, maternal stress or treatment during pregnancy with dexamethasone (which crosses the placenta) or inhibitors of fetoplacental 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2), the physiological "barrier" to maternal glucocorticoids, reduces birth weight and programs permanent offspring hypertension, hyperglycemia, and anxiety behaviors. It remains uncertain whether such effects are mediated indirectly via altered maternal function or directly on the fetus and its placenta. To dissect this critical issue, we mated 11beta-HSD2(+/-) mice such that each pregnant female produces +/+, +/-, and -/- offspring and compared them with offspring of homozygous wild-type and -/- matings. We show that 11beta-HSD2(-/-) offspring of either +/- or -/- mothers have lower birth weight and exhibit greater anxiety than 11beta-HSD2(+/+) littermates. This provides clear evidence for the key role of fetoplacental 11beta-HSD2 in prenatal glucocorticoid programming.


Assuntos
Ansiedade/metabolismo , Comportamento Animal , Peso ao Nascer , Glucocorticoides/metabolismo , Síndrome de Excesso Aparente de Minerolocorticoides/embriologia , Síndrome de Excesso Aparente de Minerolocorticoides/metabolismo , Placenta/enzimologia , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Animais , Ansiedade/complicações , Feminino , Feto/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mães , Gravidez
16.
Am J Hum Biol ; 14(4): 476-85, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12112569

RESUMO

During April-May 2000 somatic data were collected on 236 males and 191 females ages 6, 9, 13, and 15 years residing in rural areas around the communities of Ankye, Euisung, and Kunwi in Kyungsang Puk Do province, South Korea, and 237 males and 219 female of the same ages born and reared at Taegu in families of "rural to urban migrants." Comparisons were made between urban and rural groups for measures of body size and form, skinfold thickness, the body mass index (BMI), and estimated arm muscle area (ARM). Age at menarche was obtained from school records for the 13- and 15-year-olds. The data were analyzed in separate 2 (urban-rural) x 4 (age) analyses of variance with an alpha level of P < 0.01. Age differences were significant for all dimensions. There was a significant main effect for urban-rural differences in arm girth, upper limb index, and ARM. Rural males were larger in these variables. Among females, only arm girth was significantly different. Age at menarche was significantly earlier in the urban sample (12.6 years) than in the rural sample (13.0 years). Compared with both recent and earlier data for South Korea, present-day 6-, 9-, 13-, and 15-year-old males and females are taller and heavier at every age, indicating secular gains.


Assuntos
Antropometria , População Rural , Migrantes , População Urbana , Adolescente/fisiologia , Distribuição por Idade , Criança , Feminino , Humanos , Coreia (Geográfico) , Masculino
17.
Am J Hum Biol ; 11(6): 735-744, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11533989

RESUMO

Somatic data were collected during April 1997 on 156 females ages 6, 9, 13, and 15 years, residing in urban Pusan, South Korea, and on 158 age peers residing in rural regions surrounding the city. Comparisons were made between urban and rural groups for measures of body size and form, skinfold thicknesses, the body mass index (BMI), and estimated arm muscle area (ARM). Age at menarche was retrospectively reported by the 13- and 15-year-olds. The data were analyzed in 2 (urban-rural) x 3 (age) analyses of variance with an alpha level of P < 0.05. Age differences were evident for all dimensions. A significant main effect for urban-rural differences was found for stature, lower limb height, upper limb height, shoulder width, hip width, triceps skinfold, ARM, skelic index, and the trunk width index. Regardless of age, urban children were larger than rural children. Similar means were obtained for the BMI in urban and rural girls. Age at menarche was consistent with recent results; however, the rural sample (12.4 years) was significantly earlier than the urban sample (13.1 years). Compared with data collected four decades ago, present-day 6-, 9-, 13-, and 15-year-old females are taller and heavier at every age, indicating secular gains. Pusan females are similar in stature to age peers in Taiwan, Japan, and Hong Kong, and taller than the Chinese. Am. J. Hum. Biol. 11:735-744, 1999. Copyright 1999 Wiley-Liss, Inc.

18.
Am J Hum Biol ; 9(4): 493-503, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-28561283

RESUMO

Somatic data were collected during July 1995 on 154 males, ages 6, 9, and 15 years, residing in urban Pusan, South Korea, and on 157 age peers residing in rural regions surrounding the city. Comparisons are made between urban and rural groups for measures of body size and form, skinfold thicknesses, the body mass index (BMI), and estimated arm muscle area (ARM). The data were analyzed in 2 (urban-rural) × 3 (age) analyses of variance with an alpha level of P < 0.05. Age differences were evident for all dimensions. A significant main effect for urban-rural differences was found for stature, sitting height, lower limb height, upper limb length, arm girth, calf girth, shoulder width, hip width, body weight, and the sum of skinfolds. Regardless of age, urban children were larger than rural children. The interaction was nonsignificant. Except for the trunk width index, urban and rural boys did not differ on measures of body form. Similar means were obtained for the BMI and ARM in urban and rural boys. Compared with data collected four decades ago, present day 6, 9, and 15 year old males are taller and heavier at every age, indicating secular gains. Pusan males are similar in stature to age peers in Taiwan and Japan, and taller than the Chinese. Am. J. Hum. Biol. 9:493-503, 1997. © 1997 Wiley-Liss, Inc.

19.
Am J Hum Biol ; 6(2): 153-159, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-28548265

RESUMO

Dietary intake data were gathered on 123 rural and 111 urban males, ages 6, 9, and 15 years, living in and near St. Petersburg, Russia. Data were analyzed to estimate intakes of kilocalories, protein, calcium, iron, vitamin A, thiamin, riboflavin, niacin, vitamin C, and percentage of kilocalories from protein, carbohydrate, and fat. Comparisons were made between nutrient intakes of urban and rural subjects; intakes were also compared with the Recommended Dietary Intakes (RDI) of the USSR Research Institute of Nutrition. There were no significant differences between rural and urban boys in energy intake at any age. Urban boys consumed more vitamin C at ages 6 and 9, had higher intakes of protein, calcium, and niacin at age 9, and consumed more protein at age 15. Rural boys had higher intakes of riboflavin and calcium than urban boys at age 6. Urban boys consumed larger proportions of energy as carbohydrate at age 6, protein at age 9, and both protein and fat at age 15 than rural subjects. Rural boys had higher proportions of kilocalories from fat at age 6 and carbohydrate at age 15 than urban boys. Mean nutrient intakes below the RDI were: energy for rural boys at 9 and 15 years; iron for rural subjects at ages 6 and 9 and urban boys at age 6; calcium for rural and urban boys at all ages; vitamin C for rural subjects at ages 6 and 9; vitamin A for rural and urban boys at age 15; and protein for rural boys at age 15. At age 6, rural boys had nutrient intakes superior to those of urban boys; urban nutrient intakes were better than rural at ages 9 and 15. © 1994 Wiley-Liss, Inc.

20.
Am J Hum Biol ; 5(3): 273-281, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-28548416

RESUMO

Somatic data were collected during 1988-1989 on 260 black males, ages 6, 9, and 15 years, living in Calhoun County in rural central South Carolina. Eight measures of body size, four estimates of body form, two skinfold thicknesses, and body mass index (BMI) were analyzed for central tendency and variability. Comparisons were made with earlier samples of black boys measured in Columbia City, South Carolina, during 1974-1977. At ages 9 and 15 years, the Calhoun County boys exceed Columbia City boys in standing height, sitting height, lower limb height, arm girth, and body weight. Measures of body form were similar for both groups. Among worldwide comparisons, Calhoun County boys exceed all groups in standing height and body weight. Comparisons with earlier means indicate secular gains and estimates of their magnitude. © 1993 Wiley-Liss, Inc.

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