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The present paper investigates the phenotypic parameters of stimulation markers and cell immunosuppression markers in an animal model using flow cytometry analysis. Six dogs were exposed to 2, 4 or 6 Gy following a head and neck protocol. Samples of peripheral blood mononuclear cells (PBMCs) were collected before irradiation, representing standard values for all dogs (control), and at 2 h, 18 h and 30 d after irradiation. Such samples were separately assessed for surface markers with the monoclonal antibodies anti-CD5, anti-CD4 and anti-CTLA-4 by flow cytometry. A reduction in Tcell expression of CD5 and in the subpopulation expressing CD4 and an increase in CTLA-4 expression were found. No statistically significant differences were observed for the absorbed dose grouping, although the time kinetics were recorded. Radiation induced phenotypic differences between the lymphocyte lineages, reducing the CD5 and CD4 Tcell subpopulations and increasing CTLA-4 expression. The findings demonstrate the relevance of investigating the immunophenotype of irradiated subjects by examining the peripheral cell lineage.

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INTRODUÇÃO: O conhecimento da capacidade de produção de torque e de força, do comportamento da distância perpendicular ao longo do movimento e a influência destas sobre o comportamento do torque produzido é essencial para o entendimento do movimento humano e pode ser de grande utilidade para controlar a sobrecarga imposta à estrutura musculotendínea. OBJETIVO: Apresentar critérios mecânicos para a progressão de exercícios de rotação interna (RI) e externa (RE) do ombro no plano sagital. MÉTODO: Seis indivíduos foram avaliados através de um dinamômetro isocinético e de um eletrogoniômetro. A partir dos dados obtidos na coleta, foram calculadas as médias de torque, força resultante e a distância perpendicular média ponderada (DPMP) nos softwares SAD32 e Matlab®. RESULTADOS: Os ângulos em que ocorreram os picos de torque de RE e RI foram de -34º e 6º, com valores de 43 Nm e 69 Nm respectivamente, e os picos de força muscular de RE e RI ocorreram nos 35º e -14º, sendo que os valores nessas angulações foram de 10227 N e 8464 N, respectivamente. A DPMP dos RE apresentou um comportamento crescente ao longo de toda amplitude de movimento (ADM), tendo seu pico no final da amplitude, ou seja, em -50º (0,91cm); e a DPMP dos RI apresentou-se praticamente constante, com seu maior valor aos 50º (0,96cm). CONCLUSÕES: Os critérios mecânicos para a progressão de exercícios de rotação interna e externa são: torque, força e distância perpendicular média ponderada, porque, baseado em seus comportamentos, é possível promover diferentes sobrecargas sobre a estrutura musculotendínea.

INTRODUCTION: Knowledge of torque and force production capacity and moment arm patterns throughout the movement, and their influence on the torque produced, are essential for understanding human movement and may be of great use for controlling the overload imposed on the muscle-tendon structure. OBJECTIVE: To present mechanical criteria for progression in internal rotation (IR) and external rotation (ER) exercises of the shoulder in the sagittal plane. METHOD: Six individuals were assessed using an isokinetic dynamometer and an electrogoniometer. From the data collected, the mean torque, mean resultant force and weighted mean moment arm were calculated using the SAD32 and Matlab® software. RESULTS: The angles at which the peak ER and IR torque occurred were -34º and 6º with values of 43 Nm and 69 Nm, respectively. The peaks for ER and IR muscle force were at 35º and -14º, and the values at these angles were 10227 N and 8464 N, respectively. The weighted mean moment arm for ER presented an increasing pattern over the whole range of motion (ROM) and the peak was at the end of the ROM, i.e. at -50º (0.91 cm). The weighted mean moment arm for IR was almost constant with its peak at 50º (0.96 cm). CONCLUSION: The mechanical criteria for progression in internal and external rotation exercises of the shoulder are torque, force and weighted mean moment arm because different overloads on the muscle-tendon structure can be caused according to their patterns over the ROM.

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