Serum mannose-binding lectin deficiency is associated with cryptosporidiosis in young Haitian children.

BACKGROUND: Mannose-binding lectin (MBL) is a component of the innate immune response and binds microbial surfaces through carbohydrate recognition domains. MBL deficiency may contribute to susceptibility to a variety of infectious diseases, particularly in young children. MBL binds to the Cryptosporidium sporozoite and may be important in resistance to cryptosporidiosis. METHODS: We studied the association of serum MBL levels and cryptosporidiosis in a case-control study of young Haitian children with cryptosporidiosis versus children who were control subjects. RESULTS: Ninety-nine children were enrolled, as follows: 49 children with cryptosporidiosis, 41 healthy controls, and 9 children with diarrhea from other causes. Case children were more malnourished than controls, and 49% had persistent or chronic diarrhea. At enrollment, mean serum MBL levels were markedly lower in children with cryptosporidiosis (P = .002), as was the number of children with an MBL deficiency of < or = 70 ng/mL (P = .005). In multivariate analysis, the association of cryptosporidiosis and MBL deficiency persisted (P = .002; adjusted odds ratio, 22.4), as did the association of cryptosporidiosis with general malnutrition. The subset of children with cryptosporidiosis and MBL deficiency were more likely to be male (P = .025). CONCLUSIONS: MBL may be an important component of innate immune protection against Cryptosporidium infection in young children. Additional studies are necessary to determine whether MBL intestinal losses, deficient epithelial expression, and/or genetic polymorphisms in the MBL gene contribute to MBL deficiency in cryptosporidiosis and other enteric infections in young children.

Adverse events associated with eccentric exercise protocols: six case studies.

PURPOSE: Rhabdomyolysis is a condition characterized by muscle damage and degeneration of muscle cells after strenuous, overexertion exercise. Although the incidence of severe rhabdomyolysis is rare, this condition can be dangerous and even fatal. Eccentric exercise protocols are currently being used to induce and study mild forms of muscle damage. However, serious adverse events can occur in these laboratory investigations. The purpose of this report was to expose some of the adverse events resulting from performance of eccentric exercise protocols to study muscle damage in humans. METHODS: The following case studies involved an eccentric exercise protocol where two sets of 25 maximal eccentric actions of the elbow flexors were performed, separated by a 5-min rest period. RESULTS: Case reports are presented that reveal prolonged losses in the ability of the muscle to generate force lasting 43-47 d, extreme swelling of the exercised arm lasting several weeks, and greatly elevated serum creatine kinase levels. CONCLUSIONS: Although adverse events resulting from eccentric exercise are rare, our laboratory has observed a 3% incidence rate during the past year. Investigators should be knowledgeable of the sequelae of events that are associated with muscle damage after high-force eccentric exercise and take appropriate precautions.

The primary care physician as a sports medicine and exercise advocate and activist.

This article promotes the philosophy that every office visit can and should be a sports physical examination for patients of all ages. The author educates providers about promoting exercise and preventing the preventable sports injuries. Providers are encouraged to become sports and exercise community activists.

Evolution of a successful community bicycle helmet campaign.

BACKGROUND: Bicycling injuries claim more than 900 lives each year in the United States, and the major cause of deaths is head injuries. Bicycle helmets can prevent head and brain injuries, yet helmet use rate remains low. Helmets are expensive, and their cost can be prohibitive. This study asks the question, "If bicycle helmets are made affordable, will they be worn?" METHODS: A multifaceted bicycle helmet campaign was begun in Grand Junction, Colorado, population 76,000, in 1992 and was evaluated after its first 2 years. The educational component involved presentations in local schools and at community functions, physician education, and media promotions. A discount helmet program was established through community donations, which allowed helmets to be sold to low-income families for $5 and to middle- and upper-income families for $15; approximately 2400 helmets were sold. One year later a local retailer sold helmets for $12.99; approximately 4000 helmets were sold. RESULTS: Twenty-three locations were surveyed in 3 consecutive years by observers looking for bicycle riders and the presence or absence of helmets. The base-line overall use rate in 1992 was 9.9 percent, which increased to 20.9 percent in 1993 and to 37.1 percent in 1994. There were increases in helmet use in all age groups. CONCLUSIONS: A community bicycle helmet campaign that combines affordable helmets with appropriate education can effect an increase in helmet use. A major key to a successful program is a local retailer willing to sacrifice profits to promote helmet sales and use.