Links between physical fitness and cardiovascular reactivity and recovery to psychological stressors: A meta-analysis.

A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software.

Intratracheal pulmonary ventilation keeps tracheal tubes clean without impairing mucociliary transport.

Background: Intratracheal pulmonary ventilation (ITPV) is a form of tracheal gas insufflation through a reverse thrust catheter that facilitates expiration and enhances CO2 removal. Tracheas of sheep mechanically ventilated for 3 days with gas delivered through the reverse-thrust catheter remained free of secretions, without suctioning. It was hypothesized that: 1) The expiratory flow from the lungs, combined with continuous cephalad flow from the reverse-thrust catheter keeps endotracheal tubes clean; and 2) tracheal mucus velocity is not impaired by ITPV.

A role for CD99 in T cell activation.

The function of the T cell surface protein CD99 was investigated in human CD4(+) peripheral T cells. Crosslinking of the CD99 molecule using anti-CD99 mAbs in the presence of anti-CD3 Ab resulted in a marked enhancement of proliferation. CD99 coligation also enhanced CD25 expression and early markers of T cell activation, CD69 and CD40L.

Regulation of CD40L expression by cyclic AMP: contrasting proinflammatory and inhibitory actions.

CD40L expression is well recognized to be of critical importance in initiation of the immune response. Because cAMP mediates actions of bronchodilators commonly used in asthma, the effects of cAMP in regulating the immune response are of major importance. Cyclic AMP was found to either inhibit or markedly increase CD40L expression dependent upon the mechanisms of T cell activation.