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1.
Med Sci Sports Exerc ; 51(2): 299-307, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30188362

RESUMO

INTRODUCTION: Recombinant human erythropoietin (rHuEpo) administration enhances oxygen carrying capacity and performance at sea level. It remains unknown whether similar effects would be observed in chronic altitude-adapted endurance runners. The aim of this study was to assess the effects of rHuEpo on hematological and performance parameters in chronic altitude-adapted endurance runners as compared to sea level athletes. METHODS: Twenty well-trained Kenyan endurance runners (KEN) living and training at approximately 2150 m received rHuEpo injections of 50 IU·kg body mass every 2 d for 4 wk and responses compared with another cohort (SCO) that underwent an identical protocol at sea level. Blood samples were obtained at baseline, during rHuEpo administration and 4 wk after the final injection. A maximal oxygen uptake (V˙O2max) test and 3000-m time trial was performed before, immediately after and 4 wk after the final rHuEpo injection. RESULTS: Hematocrit (HCT) and hemoglobin concentration (HGB) were higher in KEN compared to SCO before rHuEpo but similar at the end of administration. Before rHuEpo administration, KEN had higher V˙O2max and faster time trial performance compared to SCO. After rHuEpo administration, there was a similar increase in V˙O2max and time trial performance in both cohorts; most effects of rHuEpo were maintained 4 wk after the final rHuEpo injection in both cohorts. CONCLUSIONS: Four weeks of rHuEpo increased the HGB and HCT of Kenyan endurance runners to a lesser extent than in SCO (~17% vs ~10%, respectively) and these alterations were associated with similar improvements in running performance immediately after the rHuEpo administration (~5%) and 4 wk after rHuEpo (~3%).


Assuntos
Adaptação Fisiológica , Altitude , Eritropoetina/administração & dosagem , Oxigênio/sangue , Substâncias para Melhoria do Desempenho/administração & dosagem , Resistência Física/fisiologia , Corrida/fisiologia , Adulto , Dopagem Esportivo , Eritropoetina/metabolismo , Hematócrito , Hemoglobinometria , Humanos , Quênia , Masculino , Consumo de Oxigênio , Substâncias para Melhoria do Desempenho/metabolismo , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/metabolismo , Adulto Jovem
2.
Curr Sports Med Rep ; 16(6): 448-458, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29135646

RESUMO

Habitually barefoot (HB) children from the Kalenjin tribe of Kenya are known for their high physical activity levels. To date, there has been no comprehensive assessment of foot structure and function in these highly active and HB children/adolescents and link with overuse injuries. PURPOSE: The aim of this research is to assess foot structure, foot function, injury and physical activity levels in Kenyan children and adolescents who are HB compared with those who were habitually shod (HS). METHODS: Foot structure, function, injury prevalence, and physical activity levels were studied using two studies with equal numbers of HS and HB. HS and HB children and adolescents were matched for age, sex, and body mass. Foot arch characteristics, foot strength, and lower-limb injury prevalence were investigated in Study 1 (n = 76). Heel bone stiffness, Achilles tendon moment arm length and physical activity levels in Study 2 (n=62). Foot muscle strength was measured using a strength device TKK 3360 and heel bone stiffness by bone ultrasonometry. The moment arm length of the Achilles tendon was estimated from photographs and physical activity was assessed using questionnaires and accelerometers. RESULTS: Foot shortening strength was greater in HB (4.8 ± 1.9 kg vs 3.5 ± 1.8 kg, P < 0.01). Navicular drop was greater in HB (0.53 ± 0.32 cm vs 0.39 ± 0.19 cm, P < 0.05). Calcaneus stiffness index was greater (right 113.5 ± 17.1 vs 100.5 ± 116.8, P < 0.01 left 109.8 ± 15.7 vs 101.7 ± 18.7, P < 0.05) and Achilles tendon moment arm shorter in HB (right, 3.4 ± 0.4 vs 3.6 ± 0.4 cm, P < 0.05; left, 3.4 ± 0.5 vs 3.7 ± 0.4 cm, P < 0.01). Lower-limb injury prevalence was 8% in HB and 61% in HS. HB subjects spent more time engaged in moderate to vigorous physical activity (60 ± 26 min·d vs 31 ± 13 min·d; P < 0.001). CONCLUSIONS: Significant differences observed in foot parameters, injury prevalence and general foot health between HB and HS suggest that footwear conditions may impact on foot structure and function and general foot health. HB children and adolescents spent more time engaged in moderate to vigorous physical activity and less time sedentary than HS children and adolescents.


Assuntos
Pé/anatomia & histologia , Pé/fisiologia , Sapatos , Tendão do Calcâneo/anatomia & histologia , Tendão do Calcâneo/fisiologia , Adolescente , Fenômenos Biomecânicos , Calcâneo/anatomia & histologia , Calcâneo/fisiologia , Feminino , Traumatismos do Pé/epidemiologia , Calcanhar/anatomia & histologia , Calcanhar/fisiologia , Humanos , Quênia , Masculino , Força Muscular , Músculo Esquelético/fisiologia , Amplitude de Movimento Articular , Corrida/lesões
3.
Physiol Genomics ; 48(3): 202-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26757800

RESUMO

Recombinant human erythropoietin (rHuEPO) is frequently abused by athletes as a performance-enhancing drug, despite being prohibited by the World Anti-Doping Agency. Although the methods to detect blood doping, including rHuEPO injections, have improved in recent years, they remain imperfect. In a proof-of-principle study, we identified, replicated, and validated the whole blood transcriptional signature of rHuEPO in endurance-trained Caucasian males at sea level (n = 18) and Kenyan endurance runners at moderate altitude (n = 20), all of whom received rHuEPO injections for 4 wk. Transcriptional profiling shows that hundreds of transcripts were altered by rHuEPO in both cohorts. The main regulated expression pattern, observed in all participants, was characterized by a "rebound" effect with a profound upregulation during rHuEPO and a subsequent downregulation up to 4 wk postadministration. The functions of the identified genes were mainly related to the functional and structural properties of the red blood cell. Of the genes identified to be differentially expressed during and post-rHuEPO, we further confirmed a whole blood 34-transcript signature that can distinguish between samples collected pre-, during, and post-rHuEPO administration. By providing biomarkers that can reveal rHuEPO use, our findings represent an advance in the development of new methods for the detection of blood doping.


Assuntos
Dopagem Esportivo/prevenção & controle , Eritropoetina/sangue , Eritropoetina/genética , Proteínas Recombinantes/sangue , Proteínas Recombinantes/genética , Adulto , Eritropoetina/administração & dosagem , Eritropoetina/biossíntese , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/biossíntese , Transcrição Gênica
4.
Int J Emerg Med ; 1(4): 317-20, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19384648

RESUMO

The human immunodeficiency virus (HIV) pandemic in sub-Saharan Africa and other high prevalence regions continues to overwhelm health care systems. While there has been a global response to improve the delivery of antiretroviral therapy in these high prevalence regions, there are few models that have developed an adequate plan to deal with HIV specifically in resource-poor emergency department settings. In this manuscript, we report on the experience scaling up HIV care at one emergency department in a large referral hospital located in western Kenya. Specifically, we describe how rapid bedside HIV testing helps to narrow the differential diagnosis of disease processes in acute care patients and how HIV screening of patients discharged from the emergency department can detect HIV-infected individuals.

5.
AIDS Patient Care STDS ; 21(12): 981-6, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18154494

RESUMO

This paper reports the initial operational outcomes of an emergency department-based HIV testing program in a high-prevalence and resource-limited setting by describing (1) the number and percentage of patients approached, tested, and found to be HIV positive and (2) the linkage of care to the HIV clinic. A retrospective log and chart review of the initial 5 months (January 2006 to April 2006) of the HIV testing program was performed. Patients were selected for HIV testing by routine screening and by provider initiated referrals. Out of the 1371 patients who were approached for HIV testing, 1339 (97.7%) patients were tested for HIV. Three hundred twelve (22.7%) of the patients tested were HIV positive. Within a sample group of patients newly diagnosed with HIV in the department, 82% were compliant with their initial HIV clinic visit and 65% were compliant with a 1-month follow-up visit. The implementation of an emergency department-based HIV testing program in a high HIV prevalence and resource poor country is feasible with a high percentage of patients accepting HIV testing and a high percentage of positive patients presenting to follow-up care. Establishment of rapid HIV testing in emergency departments can identify significant numbers of HIV-positive patients who would otherwise remain undiagnosed and provides an education opportunity for those patients who are HIV negative.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Infecções por HIV/diagnóstico , Adulto , Coleta de Dados/métodos , Serviço Hospitalar de Emergência/organização & administração , Feminino , Infecções por HIV/epidemiologia , Humanos , Quênia/epidemiologia , Masculino , Prevalência , Estudos Retrospectivos
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