RESUMO
In the Mediterranean Sea, the Strait of Messina (MS) is a very peculiar area, connecting highly different regions and representing a privileged observatory for an early comprehension and assessment of ecosystems shifts. It is hypothesized that the outbreaks observed near the coast of many sites in the Mediterranean Sea may be the result of transport of permanent populations of P. noctiluca in pelagic waters to the coast, caused by specific hydrodynamic conditions. By both visual observations and numerical experiments our objective is twofold: (A) to help clarify whether the basin of the Aeolian Islands Archipelago (AIA), in the Southern Tyrrhenian Sea (STS), may be the site from which large populations of P. noctiluca are transported to the MS, and (B) to evaluate whether the upwelling turbulent system of the MS can be an energetic opportunity for this species. It should offer a rich habitat without jeopardizing the overall survival of the population, that is subject to stranding due to strong currents. Although very different, the two involved ecosystems (AIA and MS ) are complementary for the success of Pelagia noctiluca life cycle. Outputs obtained by coupling the 3D hydrodynamic model (SHYFEM) with a Lagrangian particle tracking model support the hypothesis of a connectivity between these two ecosystems, particularly in the first half of the year, indicating the coastal areas around the AIA as potential optimal source location for Pelagia larval stages. We support the very attractive hypothesis that two connected systems exist, the former one favours Pelagia's reproduction and acts as a nursery and the latter favours its growth due to higher productivity. We speculate that the reproductive population of the AIA is not permanent, but is renewed every year by individuals who have fed and quickly grown in the MS and who are passively transported by downwelling along canyon "corridors".
Assuntos
Dinoflagellida , Cifozoários , Animais , Ecossistema , Humanos , Mar MediterrâneoRESUMO
The contribution of chronological age, skeletal age (Fels method) and body size to variance in peak velocity derived from the Carminatti Test was examined in 3 competitive age groups of Brazilian male soccer players: 10-11 years (U-12, n=15), 12-13 years (U-14, n=54) and 14-15 years (U-16, n=23). Body size and soccer-specific aerobic fitness were measured. Body composition was predicted from skinfolds. Analysis of variance and covariance (controlling for chronological age) were used to compare soccer players by age group and by skeletal maturity status within of each age group, respectively. Relative skeletal age (skeletal age minus chronological age), body size, estimated fat-free mass and performance on the Carminatti Test increased significantly with age. Carminatti Test performance did not differ among players of contrasting skeletal maturity status in the 3 age groups. Results of multiple linear regressions indicated fat mass (negative) and chronological age (positive) were significant predictors of peak velocity derived from the Carminatti Test, whereas skeletal age was not a significant predictor. In conclusion, the Carminatti Test appears to be a potentially interesting field protocol to assess intermittent endurance running capacity in youth soccer programs since it is independent of biological maturity status.
Assuntos
Desempenho Atlético , Resistência Física/fisiologia , Esqueleto/fisiologia , Futebol , Adolescente , Determinação da Idade pelo Esqueleto , Antropometria , Atletas , Composição Corporal , Tamanho Corporal , Brasil , Criança , Humanos , MasculinoRESUMO
Objetivo. Analisar o consumo de oxigênio (VO2) acumulado e o tempo em que o VO2 é mantido (TMcg) em elevados valores durante o exercício realizado na máxima fase estável de lactato (MLSS) determinada de forma contínua (MLSScon) e intermitente (MLSSint) até à exaustão. Método. Catorze ciclistas treinados realizaram um teste incremental máximo no cicloergômetro; 2‐5 testes contínuos e 2‐4 testes intermitentes, para determinação da MLSScon e MLSSint, respectivamente; por fim mais 2 testes até a exaustão (TTE) (contínuo e intermitente), conduzidos nas respectivas cargas de MLSS. Resultados. O TTE contínuo foi significativamente menor do que o TTE intermitente (54,7 ± 10,9 vs. 67,8 ± 14,3, respectivamente; p = 0,001). O VO2 da carga (VO2cg) foi significantemente maior na condição intermitente (p < 0,05), em ambas as situações (MLSS e TTE). Por outro lado, o TMcg e o VO2 acumulado na carga (VO2ACcg) foram maiores na condição contínua (p < 0,0001), em ambas as situações. O total de VO2 acumulado (VO2ACt) foi similar entre as condições contínuas e intermitentes (104,7 ± 8,7 L vs. 103,9 ± 41,1 L para a MLSS e 193,8 ± 41,1 L vs. 226,4 ± 53,0 L para o TTE, respectivamente). Conclusão. Os exercícios contínuo e intermitente realizados com a mesma duração ou até a exaustão, e em condições metabólicas similares, apresentam valores de VO2ACt similares, embora o TMcg e o VO2ACcg sejam inferiores no exercício intermitente (AU)
Objetivo. Analizar el consumo de oxígeno (VO2) acumulado y el tiempo en que el VO2 es mantenido (TMcg) en valores elevados, durante el ejercicio realizado en la máxima fase estable de lactato (MLSS), determinada de forma continua (MLSScon) e intermitente (MLSSint) hasta el agotamiento. Método. Catorce ciclistas entrenados realizaron un test incremental máximo en el cicloergómetro; 2‐5 test continuos y 2‐4 test intermitentes, para determinación de la MLSScon y MLSSint, respectivamente; por último realizaron 2 test hasta el agotamiento (TTE) (continuo e intermitente), a las respectivas cargas de MLSS. Resultados. El TTE continuo fue significativamente menor que el TTE intermitente (54,7 ± 10,9 vs. 67,8 ± 14,3, respectivamente; p = 0,001). El VO2 de la carga (VO2cg) fue significativamente mayor en la condición intermitente (p < 0,05), en ambas situaciones (MLSS y TTE). Por otro lado, el TMcg y el VO2 acumulado en la carga (VO2ACcg) fueron mayores en la condición continua (p < 0,0001), en ambas las situaciones. El total de VO2 acumulado (VO2ACt) fue similar entre las condiciones continuas e intermitentes (104,7 ± 8,7 L vs. 103,9 ± 41,1 L para a MLSS y 193,8 ± 44,1 L vs. 226,4 ± 53,0 L para el TTE, respectivamente). Conclusión. Los ejercicios continuo e intermitente realizados con la misma duración o hasta el agotamiento, y en condiciones metabólicas similares presentan valores de VO2ACt similares, aunque el TMcg y el VO2ACcg sean inferiores en el ejercicio intermitente (AU)
Objective. The aim of this study was to analyse the accumulated oxygen uptake (VO2), as well the maintained time (TMcg) at high levels during a maximal lactate steady state (MLSS) exercise, determined in continuous (MLSScon) and intermittent (MLSSint) modes, until exhaustion. Method. Fourteen trained cyclists performed an incremental maximal testing; 2‐5 continuous and 2‐4 intermittent constant workload trials, in order to identify the MLSScon and MLSSint, respectively; two tests until exhaustion (TTE) (continuous and intermittent) were conducted using their respective MLSS workloads. Results. The continuous TTE was significantly lower than TTE at intermittent protocol (54.7 ± 10.9 vs. 67.8 ± 14.3 min; p = 0.001). The VO2 at target workload (VO2cg) was higher at intermittent exercise (p < 0.05), at both situations (MLSS and TTE). On the other hand, TMcg and the VO2 accumulated in MLSS workloads (VO2ACcg) were higher during continuous mode (p < 0.0001), at both situations. The total VO2 accumulated (VO2ACt) was similar between intermittent and continuous cycling (MLSS: 104.7 ± 8.7 L vs. 103.9 ± 41.1 L and TTE: 193.8 ± 41.1 L vs. 226.4 ± 53.0 L, respectively). Conclusion. When MLSS continuous and intermittent were performed with same duration or until exhaustion, the VO2ACt was similar, although the TMcg and VO2ACcg were smaller during intermittent exercise (AU)
Assuntos
Humanos , Masculino , Adulto , Consumo de Oxigênio/fisiologia , Ciclismo/classificação , Ciclismo/fisiologia , Ciclismo/tendências , Esforço Físico/fisiologia , Ácido Láctico/análise , Ácido Láctico/sangue , Cinética , Metabolismo/fisiologia , Esportes/normas , Esportes/tendências , Índice de Massa Corporal , Declaração de Helsinki , Desenvolvimento ExperimentalRESUMO
Objetivo: O presente estudo teve como objetivo analisar os efeitos de diferentes métodos de treinamento intervalado (TI) nos parâmetros fisiológicos e no desempenho de ciclistas competitivos. Método: A classificação dos métodos de TI foram: a) sub-máximo (TIsub), b) máximo (TImax) e c ) supra-máximo (TIsup). A estratégia de busca incluiu os seguintes termos: treinamento intervalado, treinamento intervalado em ciclistas, treinamento intervalado de alta intensidade, treinamento intervalado de alta intensidade em ciclistas e sprint. Foram consultadas as seguinte bases de dados: PubMed, Google Scholar e SPORTDiscus. Para isso, foi realizada uma pesquisa entre julho de 2011 e fevereiro de 2012. Resultados: Dentre as diferentes metodologias de TI em ciclistas competitivos, todos os métodos foram suficientes para demonstrar melhorias na potência aeróbia máxima (Pmax), consumo máximo de oxigênio (VO2max), limiares fisiológicos, tempo de exaustão (Tlim) e contra-relógio de 40 km no ciclismo (CR40km ) em ciclistas competitivos. Conclusão: Portanto, os três métodos de TI demonstraram que são necessárias de 6-8 sessões de treino durante um período de 4-6 semanas para se obter ganhos nas variáveis fisiológicas e na performance em ciclistas competitivos
Objetivo. En la presente investigación hemos planteado como objetivo analizar los efectos de diferentes métodos de entrenamiento de intervalos (EI) en los parámetros de la capacidad fisiológica y el desempeño de los ciclistas de competición. Método. La clasificación de los métodos de EI es: a) sub-máxima (EIsub), b) máxima (EImax), y c) supramáxima (EIsup). La estrategia de búsqueda incluyó los términos siguientes: entrenamiento de intervalos, entrenamiento de intervalos en el ciclismo, entrenamiento de intervalo de alta intensidad, entrenamiento de intervalo de alta intensidad en el ciclismo y sprint. Para este fin, se realizó una búsqueda entre julio de 2011 y febrero de 2012 en las bases de datos: PubMed y Google Scholar SPORTDiscus. Resultados. Entre las diferentes metodologías de EI en ciclistas de competición, todos los métodos fueron suficientes para demostrar mejoras de la potencia aeróbica máxima (Pmax), el consumo máximo de oxígeno (VO2max), los umbrales fisiológicos, tiempo hasta el agotamiento (Tlim) y la prueba de 40 km de contrarreloj de ciclismo (CR40km). Conclusión. Los tres métodos de EI mostraron que es necesario 6-8 sesiones de entrenamiento durante un período de 4-6 semanas para que los ciclistas entrenados mejoraron las variables fisiológicas y de rendimiento (AU)
Objective. The aim of this study was to analyze the effects of different methods of interval training (IT) on physiological variables and performance in competitive cyclists. Method. The classification of the IT methods were: a) sub-maximal (ITsub), b) high (ITmax) and c) supramaximum (ITsup). The search strategy included the following terms: interval training, interval training on cycling, high intensity interval training, high intensity interval training in cycling and sprint. We choose for the followed databases: PubMed, Google Scholar and SPORTDiscus. For this purpose, a search were in a period between July 2011 and February 2012. Results. The different methods of IT increased maximal aerobic power (Pmax), maximum oxygen consumption (VO2max), physiological thresholds, time to exhaustion (Tlim) and 40-km cycling time trial CR40km ) in competitive cyclists. Conclusion. Therefore, the three methods of IT showed that 6-8 sessions of training during 4-6 weeks isnecessary to improve physiological variables and cycling performance in competitive cyclists (AU)
Assuntos
Humanos , Ciclismo/fisiologia , Educação Física e Treinamento , Desempenho Atlético/fisiologia , Exercício Físico/fisiologia , Técnicas de Exercício e de Movimento/métodosRESUMO
Here, we established a program of low-intensity aerobic exercise and compared the effects of exercise preoperative, postoperative, and a combination of both pre- and postoperative protocols on recovery from sciatic nerve crush injury in mice using behavioral, biochemical, and morphological assays. Sciatic nerve crush was performed in adult male mice. The animals were submitted to preoperative (for 2 weeks), postoperative (for 2 weeks), and a combination of preoperative-postoperative (for 4 weeks) training protocols. During the training period, functional recovery was monitored using the Sciatic Functional Index, the Sciatic Static Index, and mechanical and cold hypersensitivity analyses. Morphological and biochemical alterations were analyzed on the 14th day post-crushing. The functional recovery values of all of the exercised groups were significantly better than the nonexercised group. Biochemically, all of the exercise groups showed a reduction in the increase of interleukin-1ß (IL-1ß) in the sciatic nerve and in the IL-1ß and interleukin-6 receptor (IL-6R) levels in the spinal cord. However, the levels of tumor necrosis factor alpha (TNF-α) decreased only in the postoperative group and in the combination exercise protocols. In the morphological analysis, the combination exercise subjects presented an increase in fiber and axon diameter, in the myelination degree and in the number of myelinated fibers. The present study showed that pre- and postoperative exercise achieved values for functional and morphological sciatic nerve regeneration that were significantly better than either the preoperative or postoperative protocols. This experimental study suggests that physical exercise can restore motor and nerve function to a substantial degree when performed using a prophylactic and therapeutic approach.
Assuntos
Citoproteção/fisiologia , Terapia por Exercício/métodos , Regeneração Nervosa/fisiologia , Condicionamento Físico Animal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Neuropatia Ciática/fisiopatologia , Neuropatia Ciática/terapia , Animais , Modelos Animais de Doenças , Masculino , CamundongosRESUMO
Patients suffering from depression frequently display hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA) resulting in elevated cortisol levels. One main symptom of this condition is anhedonia. There is evidence that exercise training can be used as a rehabilitative intervention in the treatment of depressive disorders. In this scenario, the aim of the present study was to assess the effect of an aerobic exercise training protocol on the depressive-like behavior, anhedonia, induced by repeated dexamethasone administration. The study was carried out on adult male Wistar rats randomly divided into four groups: the "control group" (C), "exercise group" (E), "dexamethasone group" (D) and the "dexamethasone plus exercise group" (DE). The exercise training consisted of swimming (1 h/d, 5 d/wk) for 3 weeks, with an overload of 5% of the rat body weight. Every day rats were injected with either dexamethasone (D/DE) or saline solution (C/E). Proper positive controls, using fluoxetine, were run in parallel. Decreased blood corticosterone levels, reduced adrenal cholesterol synthesis and adrenal weight (HPA disruption), reduced preference for sucrose consumption and increased immobility time (depressive-like behavior), marked hippocampal DNA oxidation, increased IL-10 and total brain-derived neurotrophic factor (BDNF; pro-plus mature-forms) and a severe loss of body mass characterized the dexamethasone-treated animals. Besides increasing testosterone blood concentrations, the swim training protected depressive rats from the anhedonic state, following the same profile as fluoxetine, and also from the dexamethasone-induced impaired neurochemistry. The data indicate that physical exercise could be a useful tool in preventing and treating depressive disorders.
Assuntos
Anedonia/fisiologia , Depressão/reabilitação , Condicionamento Físico Animal/métodos , Animais , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Depressão/complicações , Dexametasona/toxicidade , Modelos Animais de Doenças , Expressão Gênica/fisiologia , Glucocorticoides/toxicidade , Hipocampo/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Interleucina-10/biossíntese , Masculino , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , NataçãoRESUMO
BACKGROUND: The aim of this study was to evaluate the number of conversions from spinal anesthesia (SA) into general anesthesia (GA) in a large number of patients who underwent surgery over a period of twenty-one years. METHODS: From the hospital's database, all surgical procedures performed under SA between January 1, 1988 and December 31, 2008 were retrieved. From this file, all SA cases converted into GA cases requiring endotracheal intubation were selected. Patients were divided in four groups, according to the reason for GA: IMPOSS (SA impossible to perform), FAIL (SA non profound enough for allowing surgery, even with light sedation), INSUFF (SA inadequate for unexpected prolonged duration of surgery), and COMPL (occurrence of complications associated with SA and requiring rapid control of ventilation). Anesthesiologists who performed SA were divided according their experience. The outcomes of patients converted to GA were compared with a matched sample of patients who received planned GA. RESULTS: A total of 35,960 SA cases were performed from 1988 to 2008; 29,220 and 6,740 SA cases were for elective and emergency surgery, respectively. Two hundred seventeen (0.6%) SA cases were converted into GA cases; 80.2% and 19.8% of the conversions were recorded in elective and emergency operations, respectively, with obstetric operations being the most prevalent (82/217). The primary reasons for the conversions, in a rank order, were INSUFF 107 (49.3%), FAIL 84 (38.7%), IMPOSS 13 (5.9%), and COMPL 13 (5.9%). Complications more frequently occurred in the aged population (P<0.05). Anesthesiologists with less experience had higher percentages of FAIL, IMPOSS, INSUFF, and COMPL SA cases in comparison with experienced anesthesiologists (odd ratios being 4.7, 3.0, 2.4, and 4.4, respectively). There was no difference in the frequency of complications compared to a matched sample of 1,000 patients who underwent GA (P=0.65). CONCLUSION: SA has been found to be a safe and highly effective technique. Failure of SA was infrequent in a large number of patients surveyed and most often occurred with less experienced anesthesiologists. Conversion to GA did not produced different outcomes in comparison with planned GA. Prospective studies with a definite protocol for recording data performed on a large number of patients may help in determining the factors associated with conversion from SA into GA and how to avoid these unexpected situations.
Assuntos
Anestesia Geral/estatística & dados numéricos , Raquianestesia/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The objective of this study was to compare the effect of different strength training protocols added to endurance training on running economy (RE). Sixteen well-trained runners (27.4 +/- 4.4 years; 62.7 +/- 4.3 kg; 166.1 +/- 5.0 cm), were randomized into two groups: explosive strength training (EST) (n = 9) and heavy weight strength training (HWT) (n = 7) group. They performed the following tests before and after 4 weeks of training: 1) incremental treadmill test to exhaustion to determine of peak oxygen uptake and the velocity corresponding to 3.5 mM of blood lactate concentration; 2) submaximal constant-intensity test to determine RE; 3) maximal countermovement jump test and; 4) one repetition maximal strength test in leg press. After the training period, there was an improvement in RE only in the HWT group (HWT = 47.3 +/- 6.8 vs. 44.3 +/- 4.9 ml . kg (-1) . min (-1); EST = 46.4 +/- 4.1 vs. 45.5 +/- 4.1 ml . kg (-1) . min (-1)). In conclusion, a short period of traditional strength training can improve RE in well-trained runners, but this improvement can be dependent on the strength training characteristics. When comparing to explosive training performed in the same equipment, heavy weight training seems to be more efficient for the improvement of RE.
Assuntos
Resistência Física/fisiologia , Treinamento Resistido/métodos , Corrida , Adulto , Humanos , Ácido Láctico/sangue , Consumo de Oxigênio/fisiologia , Adulto JovemRESUMO
Zooplankton are an essential component of the marine and estuarine food chains. The ecotoxicological risk to zooplanktonic communities, estimated through the use of the biomarkers, can be used as an early warning signal of a potential alteration of the ecosystem health. The aim of this project was to evaluate the potential use of several biomarkers (esterases, mixed function oxidases, porphyrins) in zooplanktonic organisms. The acetylcholinesterase activity (AChE) was determined in homogenates of whole organisms of 10 different zooplanktonic crustaceans. Mean activity of AChE was 10.05 micromol/min/g for Acartia margalefi; 3.30 for Acartia latisetosa; 79.70 for Siriella clausi; 49.97 for Diamysis bahirensis; 7.48 for Siriella armata; 14.20 for Mysidopsis gibbosa; 4.49 for Euphausia crystallorophias; 1.66 for Euphausia superba; 2.74 for Streetsia challengeri; 13.26 for Meganycthiphanes norvegica. The species moreover showed a linear increase in enzyme activity in relation to the increase in sample concentration. The key result of this study concerns the different AChE activity basal values of the crustaceans' different species.
Assuntos
Acetilcolinesterase/farmacologia , Biomarcadores/análise , Crustáceos/fisiologia , Zooplâncton/fisiologia , Acetilcolinesterase/análise , Animais , Monitoramento Ambiental , Valores de ReferênciaRESUMO
BACKGROUND: In order to manage the operating theatre and guarantee constant improvement in the quality of procedures, it is indispensable to be able to have available a computerised workstation to enable the team to collect data and analyse them. METHODS: We used our anaesthesia department's computer workstation to retrospectively analyse operating sessions over a 16 month period during which organisational adjustments were made to optimise patient turnover and maximise the utilisation of operating theatres. Meantime we studied and compared the trend in anaesthesiological quality through the use of certain structural, process and outcome indicators. RESULTS: During the period under study an improvement was noted in the efficiency of operating theatre procedures (reduction in entry time of the first patient into the theatre, time between one case and the next and subutilisation of the operating theatre, p<0.05). As regards data on the quality of anaesthesiological assistance to the patient, no significant differences were noted when comparing the four periods examined. CONCLUSIONS: To make the operating complex work more efficiently, it is necessary to have available a computer system that makes it possible to continuously monitor theatre operation. The improvement initiatives undertaken led to a more effective utilisation of the operating theatre but did not produce a significant increase in productivity. In spite of the increased work load, analysis of the trend in quality indicators as regards anaesthesiological procedures did not reveal any modification.
Assuntos
Anestesia/normas , Salas Cirúrgicas/organização & administração , Computadores , Humanos , Informática Médica , Garantia da Qualidade dos Cuidados de Saúde , Estudos RetrospectivosRESUMO
Zooplankton is an essential component of the food chains of marine and brackish environments. Ecotoxicological risk to zooplankton, evaluated by the biomarker approach, can be used as an early warning signal of risk to the health of marine ecosystems. The aim of this project is to evaluate the application of certain biomarkers in zooplankton. In the present paper, laboratory and field studies were performed with the copepods Acartia margalefi, Acartia latisetosa and the mysid Siriella clausi. Acetylcholinesterase activity (AChE) was determined in homogenates of whole organisms. Mean AChE activity was 10.05 micromol min g(-1) for A. margalefi, 3.30 micromol min g(-1) for A. latisetosa and 79.70 micromol min g(-1) for S. clausi. A. margalefi and S. clausi also showed a linear increase in enzyme activity with increasing concentrations of samples. Preliminary laboratory work was also carried out with specimens of A. latisetosa, which were exposed to an organophosphorus insecticide (parathion). Moderate inhibition of AChE (19%) with respect to controls was observed. AChE activities were two orders of magnitude higher in the zooplankton than in hemolymph samples of the decapod Carcinus aestuarii (Fossi et al., 1996) indicating that these species have a high metabolic rate, which makes them suitable for biomarker studies.