Epidemiology of concussion in collegiate and high school football players.

Despite evolutionary changes in protective equipment, head injury remains common in football. We investigated concussion in football and associated epidemiologic issues such as 1) incidence of injury, 2) common signs and symptoms, and 3) patterns in making return-to-play decisions. We received 242 of 392 surveys (62%) that were sent to high school and collegiate certified athletic trainers at the beginning of three football seasons.

Resistance to common viruses during intralymphatic injections of tumor cell vaccines. Correlation with circulating cytokines.

Patients with advanced malignancies who received intralymphatic injections of irradiated tumor cell suspensions ("vaccines") were unexpectedly found to be resistant to common viral diseases; 17 patients with a documented past history of viral infections who have been observed for 48 to 148 months (median 108 months), were analyzed. The resistance to viruses was found to correlate closely with the presence, in the serum, of certain cytokines. Specifically, the interleukins, -2, -6, -8 and interferon-gamma, at low but sustained levels appeared to be possibly responsible for the nonspecific protection against viral infections obtained by intralymphatic injections of cellular material.

Effects of 13 cis-retinoic acid on growth and differentiation of human follicular carcinoma cells (UCLA R0 82 W-1) in vitro.

Dedifferentiation of human thyroid tumors is frequently found in humans. The effect of retinoids (13 cis-RA) was studied on the proliferation and differentiation of a human follicular cell line in vitro (UCLA R0 82 W-1). A significant and dose-dependent reduction (P less than 0.

[Diagnostic tests for hypersensitivity to halogen compounds].

The authors present a critical analysis of immunological tests used by some authors to establish the diagnosis of halothane-induced hepatitis. These tests include the lymphocyte transformation test (LTT), the leukocyte migration inhibition test (LMIT) and detection of auto-antibodies. It has not been possible for all investigators to reproduce the results of these tests.

[Effect of general anesthesia on complement. Effect of the atmosphere in the operating room on the immune response of anesthesiologists].

Variations in the C3 and C4 fractions of complement were studied in 15 patients who underwent surgery with either spinal anesthesia (5 cases) or general anesthesia using nitruos oxyde and a halogen compound (10 cases). Little peroperative variation was observed. An increase in C4 was observed in all cases postoperatively.

[Experimental study of conjugates of a catabolite common to halothane, enflurane and fluroxene in guinea pigs].

The authors sensitized guinea pigs to a halothane catabolite, trifluoroacetic acid, combined with guinea pig albumin. They then exposed the animals to halothane. There was no correlation between the presence of humoral and cell-mediated immune reactions obtained with the catabolite and the incidence of liver necrosis.

Humoral immunity to a metabolite of halothane, fluroxene, and enflurane.

Trifluoroacetate, a common metabolite of halothane, fluroxene, and enflurane, conjugated to guinea-pig albumin elicits specific serum antibody in guinea pigs. Two classes of antibodies were found: hemolytic, gamma-2, and anaphylactic, gamma-1. Repeated injections of the antigen, trifluoroacetyl-guinea pig albumin, often led to disappearance of circulating antibodies.