Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
Scand J Med Sci Sports ; 28(1): 57-64, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28493600

RESUMO

Sphingosine-1-phosphate (S1P) is a bioactive lysosphingolipid that is found in relatively high concentration in human plasma. Erythrocytes, endothelial cells, and activated platelets are the main sources of circulating S1P. The majority of plasma S1P is transported bound to high-density lipoprotein (HDL) and albumin. In recent years, HDL-bound S1P attracted much attention due to its cardioprotective and anti-atherogenic properties. We have previously found that endurance-trained athletes are characterized by higher plasma S1P concentration compared to untrained individuals. This finding prompted us to examine the effect of endurance training on S1P metabolism in blood. Thirteen healthy, untrained, male subjects completed an 8-week training program on a rowing ergometer. Three days before the first, and 3 days after the last training session, blood samples were drawn from an antecubital vein. We found that total plasma S1P concentration was increased after the training. Further analysis of different plasma fractions showed that the training selectively elevated HDL-bound S1P. This effect was associated with activation of sphingosine kinase in erythrocytes and platelets and enhanced S1P release from red blood cells. We postulate that increase in HDL-bound S1P level is one of the mechanisms underlying beneficial effects of regular physical activity on cardiovascular diseases.


Assuntos
Exercício Físico , Lipoproteínas HDL/sangue , Lisofosfolipídeos/sangue , Resistência Física , Plasma/química , Esfingosina/análogos & derivados , Plaquetas/enzimologia , Eritrócitos/enzimologia , Humanos , Masculino , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Esfingosina/sangue , Adulto Jovem
2.
Biol Sport ; 33(4): 335-343, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28090137

RESUMO

The aim of this study was to determine the relationship between the degree of cardiorespiratory fitness and the function of the right ventricle (RV). 117 rowers, age 17.5±1.5 years. All subjects underwent cardiopulmonary exercise. Standard echocardiography and 2D speckle tracking echocardiography with evaluation of longitudinal strain in each segment of the RV (basal - RVLS-B; mid - RVLS-M, apical - RVLS-A) and global RV free-wall strain (RVLS-G) were performed. RVLS-B values were lower compared to the RVLS-M (-25.8±4.4 vs -29.3±3.5; p<0.001) and RVLS-A values (-25.8±4.4 vs -26.2±3.4; p=0.85). Correlations between VO2max and RVLS were observed in men: RVLS-G strain (r = 0.43; p <0.001); RVLS-B (r = 0.30; p = 0.02); RVLS-M (r = 0.38; p = 0.02). A similar relationship was not observed in the group of women. The strongest predictors corresponding to a change in global and basal strain were VO2max and training time: RVLS-G (VO2max: ß = 0.18, p = 0.003; training time: ß = -0.39; p = 0.02) and RVLS-B (VO2max: ß = 0.23; p = 0.0001 training time: ß = -1.16; p = 0.0001). The global and regional reduction of RV systolic function positively correlates with the level of fitness, and this relationship is observed already in young athletes. The character of the relationship between RV deformation parameters and the variables that determine the physical performance depend on gender. The dependencies apply to the proximal fragment of the RV inflow tract, which may be a response to the type of flow during exercise in endurance athletes.

3.
Biol Sport ; 30(4): 249-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24795498

RESUMO

The aim of the study was to examine the possible relationship between I/D polymorphism of ACE gene and selected indices of aerobic capacity among male and female athletes practising winter endurance sports. Sixty-six well-trained athletes (female n = 26, male n = 40), aged 18.4 ± 2.8 years, representing winter endurance sports (cross-country skiing, n = 48; biathlon, n = 8; Nordic combined, n = 10) participated in the study. Genotyping for ACE I/D polymorphism was performed using polymerase chain reaction. Maximal oxygen consumption (VO2max), maximal running velocity (Vmax) and running velocity at anaerobic threshold (VAT4) were determined in an incremental test to volitional exhaustion on a motorized treadmill. The ACE genotype had no significant effect on absolute VO2max, relative VO2max (divided by body mass or fat free body mass), VAT4 or Vmax. No interaction effect of gender x ACE genotype was found for each of the examined aerobic capacity indices. ACE gene variation was not found to be a determinant of aerobic capacity in either female or male Polish, well-trained endurance athletes participating in winter sports.

4.
Arch Pediatr ; 29(7): 502-508, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35934605

RESUMO

The French Transplant Health Authority (Agence de la Biomédecine) has broadened its organ- and tissue-donation criteria to include pediatric patients whose death is defined by circulatory criteria and after the planned withdrawal of life-sustaining therapies (WLST) (Maastricht category III). A panel of pediatric experts convened to translate data in the international literature into recommendations for organ and tissue donation in this patient subgroup. The panel estimated that, among children aged 5 years or over with severe irreversible neurological injury (due to primary neurological injury or post-anoxic brain injury) and no progression to brain death, the number of potential donors, although small, deserves attention. The experts emphasized the importance of adhering strictly to the collegial procedure for deciding to withdraw life support. Once this decision is made, the available data should be used to evaluate whether the patient might be a potential donor, before suggesting organ donation to the parents. This suggestion should be reserved for parents who have unequivocally manifested their acceptance of WLST. The discussion with the parents should include both the pediatric intensive care unit (PICU) team under the responsibility of a senior physician and the hospital organ- and tissue-procurement team. All recommendations about family care during the end of life of a child in the PICU must be followed. The course and potential challenges of organ donation in Maastricht-III pediatric patients must be anticipated. The panel of experts recommended strict compliance with French recommendations (by the Groupe Francophone de Réanimation et Urgences Pédiatriques) about WLST and providing deep and continuous sedation until circulatory arrest. The experts identified the PICU as the best place to implement life-support discontinuation and emphasized the importance of returning the body to the PICU after organ donation. French law prohibits the transfer of these patients from one hospital to another. A description of the expert-panel recommendations regarding the organization and techniques appropriate for children who die after controlled circulatory arrest (Maastricht III) is published simultaneously in the current issue of this journal..


Assuntos
Parada Cardíaca , Obtenção de Tecidos e Órgãos , Criança , Humanos , Unidades de Terapia Intensiva Pediátrica , Doadores de Tecidos
5.
Arch Pediatr ; 29(7): 509-515, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36055866

RESUMO

A panel of pediatric experts met to develop recommendations on the technical requirements specific to pediatric controlled donation after planned withdrawal of life-sustaining therapies (Maastricht category III). The panel recommends following the withdrawal of life-sustaining therapies protocol usually applied in each unit, which may or may not include immediate extubation. The organ retrieval process should be halted if death does not occur within 3 h of life-support discontinuation. Circulatory arrest is defined as loss of pulsatile arterial pressure and should be followed by a 5-min no-touch observation period. Death is declared based on a list of clinical criteria assessed by two senior physicians. The no-flow time should be no longer than 30, 45, and 90 min for the liver, kidneys, and lungs, respectively. At present, the panel does not recommend pediatric heart donation after death by circulatory arrest. The mean arterial pressure cutoff that defines the start of the functional warm ischemia (FWI) phase is 45 mmHg in patients older than 5 years and/or weighing more than 20 kg. The panel recommends normothermic regional perfusion in these patients. The FWI phase should not exceed 30 and 45 min for retrieving the pancreas and liver, respectively. There is no time limit to the FWI phase for the lungs and kidneys. The panel recommends routine sharing of experience with Maastricht-III donation among all healthcare institutions involved in order to ensure optimal outcome assessment and continuous discussion on the potential difficulties, notably those related to the management of normothermic regional perfusion in small children.


Assuntos
Parada Cardíaca , Obtenção de Tecidos e Órgãos , Extubação , Criança , Morte , Humanos , Perfusão/métodos
6.
J Sports Med Phys Fitness ; 48(3): 279-84, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18974711

RESUMO

AIM: The aim of the investigation was to assess the effects of the resistive inspiratory muscle training (IMT) in elite male rowers. METHODS: Fifteen senior rowers were assayed for the maximal inspiratory mouth pressure (PImax) and maximal oxygen uptake (VO2max), and then randomized into two groups: the control and the experimental group. The latter athletes, in addition to basic training, were subjected to the 11-week IMT consisting of a series of 30 inspiratory efforts performed twice a day. Athletes from the control group did only the basic training. RESULTS: No significant relations were detected between the initial values of PImax and the VO2max value. After 6 weeks of IMT the PImax values increased by 20+/-10% (P < 0.05), whereas the final improvement (after 11 weeks of IMT) equaled to 34+/-19% (P < 0.05). In the control group, the final increase equaled to 4+/-9% and was statistically insignificant. Compared to the values obtained at the end of IMT, 14 weeks after cessation of the training PImax insignificantly decreased in the experimental group by 10+/-9%, but the measured values were still significantly higher than before the commencement of IMT. CONCLUSION: The data obtained corroborate the observations that in well-trained athletes the introduction of the principle of incremental inspiratory resistance allows to improve methodically the inspiratory muscles' strength. Once the essential period of IMT has been completed, the training volume should be reduced in order to secure the attained level of the inspiratory muscles' strength.


Assuntos
Tolerância ao Exercício/fisiologia , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Consumo de Oxigênio/fisiologia , Aptidão Física/fisiologia , Músculos Respiratórios/fisiologia , Navios , Adulto , Humanos , Capacidade Inspiratória/fisiologia , Masculino
7.
Eur J Appl Physiol Occup Physiol ; 71(5): 439-43, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8565976

RESUMO

Relationships between the postexercise values of blood lactate concentration, pH, oxygen uptake, heart rate, power output on the one hand, and the pre- and postexercise blood cortisol concentrations on the other, were studied in 74 male and 40 female athletes (wrestlers and senior and junior rowers), performing graded exercise of increasing intensity. The senior rowers, junior rowers and wrestlers had different exercise protocols. The senior rowers of both sexes had significantly higher rest concentrations of serum cortisol than the junior athletes. A significant correlation between postexercise lactate concentrations and pre-exercise cortisol concentrations was found in all the male groups ("common" r = 0.515, P < 0.001), but not in the female ones (r = 0.162). It was concluded that the pre-exercise cortisol concentrations might condition anaerobic-glycolytic metabolism in physical exercise.


Assuntos
Exercício Físico/fisiologia , Hidrocortisona/sangue , Esportes , Adolescente , Adulto , Feminino , Frequência Cardíaca , Humanos , Concentração de Íons de Hidrogênio , Lactatos/sangue , Ácido Láctico , Masculino , Consumo de Oxigênio , Esforço Físico , Luta Romana
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA