Handgrip fatigue test using dynamic contractions in typical children

Objetivo: Verificar o desenvolvimento da fadiga e a influência do sexo na preensão manual durante contrações dinâmicas em crianças típicas. Métodos: Estudo transversal. Cinquenta e oito crianças, distribuídas em dois grupos de acordo com o sexo (30 meninos), com idades entre 8 e 12 anos, de ambos os sexos, realizaram sucessivas contrações dinâmicas com um dinamômetro de bulbo até atingirem o esforço máximo percebido. Os valores da primeira, da última contração do teste de fadiga e da medida após 30 segundos da última contração (contração de recuperação) foram registrados e comparados usando o modelo de regressão linear com efeitos mistos. O teste T-Student foi usado para comparar os escores de esforço percebido e o tempo até a fadiga entre os grupos. Resultados: Os valores de preensão palmar e os escores de esforço percebido diminuíram significativamente durante o teste de fadiga. Não houve diferenças entre os grupos para todas as variáveis. Conclusão: O teste de fadiga de preensão palmar utilizando contrações dinâmicas mostrou-se eficaz na indução da fadiga motora e percebida em crianças, sem diferenças entre os sexos.Objective: To verify the development of fatigue and sex-influence on the handgrip during dynamic contractions in typical children. Methods: Cross-section study. Fifty-eight children, distributed into two groups according to sex (30 boys), aged 8 to 12 years, of both sexes, performed successive dynamic contractions with a bulb dynamometer until they reached maximum perceived effort. The values from the first, the last contractions of the fatigue test, and the measure after 30-s of the last contraction (recovery contraction) were recorded and compared using the linear regression model with mixed effects. T-Student test was used to compare the perceived effort scores and time-to-fatigue between groups. Results: The handgrip values significantly decreased, and perceived effort scores significantly increased in the final measure in relation to the initial measure of the fatigue test. After the fatigue handgrip test, 30-sec of recovery was insufficient to restore the baseline handgrip values. There were no differences between the female and male groups for all variables. Conclusion: The handgrip fatigue test using dynamic contractions showed it efficiently induces motor and perceived fatigue in children, without differences between sexes

The relationship of host immune cells, cytokine and nitric oxide production to tumor cells in ovarian carcinoma

AIMS: This brief review focuses on the current understanding of the complex relationship of tumor-associated mononuclear cells (TAMs) with neoplastic cells, summarizing their immunological efficiency, cytokine profile and production of nitric oxide (NO) in the tumor microenvironment, with current insights on how this might affect tumor growth. DATA SOURCE: Data was obtained through Medline from articles indexed during the last 10 years. The main key words used in the research were: cancer, ovarian cancer, cytokine, nitric oxide (NO), mononuclear cell, lymphocyte, macrophage. SELECTION OF STUDIES AND DATA COLLECTION: 30 studies were reviewed, which contained data regarding the production of cytokines and NO by TAMs or malignant cells, and tried to establish a correlation between these mediators and tumor growth, especially in ovarian carcinoma. DATA SUMMARY: TAMs consist mainly of macrophages and T lymphocytes which present lower proliferative indices and cytotoxicity compared to autologous blood monocytes, although they are able to release various cytokines. The profile of cytokine expression could help to explain both the immunological impairment observed in patients with advanced carcinoma diseases and the potential of TAMs to exert antitumor activity, which makes these cells an attractive target for therapeutic intervention. NO is also produced in the tumor microenvironment. Several reports in animals suggest a tumoricidal role for NO, but in human tumors its role has not been well-established and may change during tumor progression