Lower extremity dexterity is associated with agility in adolescent soccer athletes.

Agility is important for sport performance and potentially injury risk; however, factors affecting this motor skill remain unclear. Here, we evaluated the extent to which lower extremity dexterity (LED) and muscle performance were associated with agility. Fourteen male and 14 female soccer athletes participated. Agility was evaluated using a hopping sequence separately with both limbs and with the dominant limb only. The LED test evaluated the athletes' ability to dynamically regulate foot-ground interactions by compressing a spring prone to buckling with the lower limb. Muscle performance included hip and knee isometric strength and vertical jump height. Correlation analyses were used to assess the associations between muscle performance, LED, and agility. Multiple regression models were used to determine whether linear associations differed between sexes. On average, the female athletes took longer to complete the agility tasks than the male athletes. This difference could not be explained by muscle performance. Conversely, LED was found to be the primary determinant of agility (double limb: R(2) = 0.61, P < 0.001; single limb: R(2) = 0.63, P < 0.001). Our findings suggest that the sensorimotor ability to dynamically regulate foot-ground interactions as assessed by the LED test is predictive of agility in soccer athletes. We propose that LED may have implications for sport performance, injury risk, and rehabilitation.

Rifabutin (ansamycin LM427) for the treatment of pulmonary Mycobacterium avium complex.

During the period October 1983 through January 1988, the Centers for Disease Control (CDC) provided the experimental drug rifabutin (ansamycin LM427) to 406 patients with severe, progressive Mycobacterium avium complex pulmonary disease who had been unresponsive to standard therapy. Selected patients were randomly assigned to doses of 150, 300, or 450 mg rifabutin. Choice of companion drugs was left to the treating physicians. In the analysis of data from this program, we examined the relationship between response to treatment, as measured by bacteriologic sputum conversion, survival, weight gain, improvement in respiratory symptoms, and subjective assessment of clinical improvement, and a variety of patient and treatment variables. Although in some of the analyses a higher rifabutin dose appeared to be associated with sputum conversion, survival, and clinical improvement, the drug did not have a marked effect on outcome. The role of rifabutin in the treatment of this disease will best be assessed in a controlled clinical trial.

Rifabutin (ansamycin LM 427): a new rifamycin-S derivative for the treatment of mycobacterial diseases.

Rifabutin (ansamycin LM 427), a semisynthetic spiropiperidyl derivative of rifamycin S, shows good in vitro activity against most mycobacterial species, including Mycobacterium avium complex. In animal models, the drug is more active against both Mycobacterium tuberculosis and Mycobacterium leprae than in rifampin, and studies indicate that rifabutin is active against some rifampin-resistant strains of both species. The drug has a long half-life (16 hr) in humans and a marked tissue tropism, with tissue levels five- to 10-fold higher than that in the serum. In animals rifabutin is no more toxic than rifampin. A large experience from the compassionate use of rifabutin for life-threatening mycobacterial infections in humans, most commonly disseminated M. avium complex disease in patients with AIDS, has also indicated relative drug safety. Although some data suggest that rifabutin is effective, firm conclusions about drug efficacy await results from controlled clinical trials.

Hepatotoxicity from isoniazid and rifampin among children treated for tuberculosis.

To estimate rates of hepatotoxicity in the United States among children treated for tuberculosis, we conducted a retrospective survey of health departments and individual practitioners. We received 874 reports suitable for analysis of children treated during 1977 to 1979. A total of 16 hepatotoxic reactions were reported; 14/430 (3.3%) children receiving isoniazid and rifampin had a hepatotoxic reaction, which approximates the rate seen in adults taking these drugs. Half of the reactions occurred during the first month of therapy, and all of the well-documented reactions were noted during the first 10 weeks. Because the likelihood of hepatotoxicity may be increased with higher drug doses, limiting the dose of isoniazid to 10 mg/kg and that of rifampin to 15 mg/kg may help minimize hepatotoxic reactions. Because more serious disease, especially disseminated tuberculosis, may further increase the risk of hepatotoxicity, close monitoring of such children receiving isoniazid and rifampin should help minimize serious hepatotoxicity. Routine biochemical monitoring may not be necessary for all children, eg, those with mild forms of disease and those with normal pretreatment liver function who are treated with lower drug doses.

Treatment of tuberculosis during pregnancy.

The pregnant woman with tuberculosis who requires treatment presents a therapeutic dilemma; therefore, we reviewed all available literature on pregnant women treated with isoniazid (INH), ethambutol (EMB), rifampin (RMP), or streptomycin (SM) and report here on the relative safety of these drugs and whether the risk of teratogenesis justifies abortion on medical grounds. Other than the ototoxicity of SM, none of these drugs in normal dosages are proved teratogens to human fetuses. We recommend the use of INH in combination with EMB for a pregnant woman with tuberculosis, if the disease is not extensive. If a third drug is warranted, then RMP could be added. Because of its ototoxicity, SM should not be used, unless RMP is contraindicated or proves unsatisfactory. Routine therapeutic abortion is not medically indicated for a pregnant woman who is taking first-line antituberculosis drugs.

Synthesis and characterization of glucuronides of 5'-hydroxy-delta9-tetrahydrocannabinol and 11-hydroxy-delta9-tetrahydrocannabinol.

Glucuronides of two metabolites of delta9-tetrahydrocannabinol, 11-hydroxy-delta9-THC and 5'-hydroxy-delta9-THC, have been synthesized and characterized. Two isomeric monoglucuronides were isolated from the incubation of each metabolite with UDP-glucuronyltransferase immobilized on beaded Sepharose. The structures of these conjugates were assigned primarily on the basis of combined gas chromatography-mass spectrometry.

Synthesis and characterization of glucuronides of Cannabinol, cannabidiol, delta9-tetrahydrocannabinol and delta8-tetrahydrocannabinol.

Partially purified glucuronyltransferase immobilized on beaded sepharose has been used to synthesize the glucuronide conjugates of cannabinol, cannabidol, delta9-tetrahydrocannabinol and delta8-tetrahydrocannabinol. Trimethylsilylated methyl esters and per(trimethylsilyl) derivatives of these conjugates have been characterized by their gas chromatographic retention times and their electron impact and ammonia chemical ionization mass spectra.