SV40 large T antigen with c-Jun down-regulates myelin P0 gene expression: a mechanism for papovaviral T antigen-mediated demyelination

Expression of myelin proteins has been shown to be altered in transgenic mice that express papovaviral large tumor (T) antigens. This paper analyzes the effect on P0 gene expression in secondary Schwann cells transfected with the SV40 T antigen gene and in Schwann cells immortalized by T antigen. In secondary Schwann cells, both T antigen and c-Jun are required for significant inhibition of the P0 promoter; expression of only one of the proteins is insufficient for repression of the P0 gene. T antigen, c-Jun (p39), and c-Jun-related protein (p47) form an immunoprecipitable complex in SV40 immortalized Schwann cell lines, and T antigen and c-Jun bind independently and as a complex to the P0 promoter. Our data suggest that the probable molecular mechanism underlying the hypomyelination observed in transgenic animals expressing T antigen may be due to the repression of the P0 gene by T antigen and c-Jun.     

Canada''s poorest citizens: looking for solutions for children

We describe three cases of CPPD crystal deposition disease in elderly patients whose main symptom was fever. Misdiagnosis of such cases is possible because of the similarity of the clinical picture to that of septic fever. The probable mechanisms causing the fever are discussed. There was spectacular improvement in these patients after a high dose of oral colchicine and loperamide and no relapse was observed during the long term administration of colchicine in a conservative dose together with supplementary magnesium.     

American College of Sports Medicine position stand. Exercise and fluid replacement

It is the position of the American College of Sports Medicine that adequate fluid replacement helps maintain hydration and, therefore, promotes the health, safety, and optimal physical performance of individuals participating in regular physical activity. This position statement is based on a comprehensive review and interpretation of scientific literature concerning the influence of fluid replacement on exercise performance and the risk of thermal injury associated with dehydration and hyperthermia. Based on available evidence, the American College of Sports Medicine makes the following general recommendations on the amount and composition of fluid that should be ingested in preparation for, during, and after exercise or athletic competition: 1) It is recommended that individuals consume a nutritionally balanced diet and drink adequate fluids during the 24-hr period before an event, especially during the period that includes the meal prior to exercise, to promote proper hydration before exercise or competition. 2) It is recommended that individuals drink about 500 ml (about 17 ounces) of fluid about 2 h before exercise to promote adequate hydration and allow time for excretion of excess ingested water. 3) During exercise, athletes should start drinking early and at regular intervals in an attempt to consume fluids at a rate sufficient to replace all the water lost through sweating (i.e., body weight loss), or consume the maximal amount that can be tolerated. 4) It is recommended that ingested fluids be cooler than ambient temperature [between 15 degrees and 22 degrees C (59 degrees and 72 degrees F])] and flavored to enhance palatability and promote fluid replacement. Fluids should be readily available and served in containers that allow adequate volumes to be ingested with ease and with minimal interruption of exercise. 5) Addition of proper amounts of carbohydrates and/or electrolytes to a fluid replacement solution is recommended for exercise events of duration greater than 1 h since it does not significantly impair water delivery to the body and may enhance performance. During exercise lasting less than 1 h, there is little evidence of physiological or physical performance differences between consuming a carbohydrate-electrolyte drink and plain water. 6) During intense exercise lasting longer than 1 h, it is recommended that carbohydrates be ingested at a rate of 30-60 g.h(-1) to maintain oxidation of carbohydrates and delay fatigue. This rate of carbohydrate intake can be achieved without compromising fluid delivery by drinking 600-1200 ml.h(-1) of solutions containing 4%-8% carbohydrates (g.100 ml(-1)). The carbohydrates can be sugars (glucose or sucrose) or starch (e.g., maltodextrin). 7) Inclusion of sodium (0.5-0.7 g.1(-1) of water) in the rehydration solution ingested during exercise lasting longer than 1 h is recommended since it may be advantageous in enhancing palatability, promoting fluid retention, and possibly preventing hyponatremia in certain individuals who drink excessive quantities of fluid. There is little physiological basis for the presence of sodium in n oral rehydration solution for enhancing intestinal water absorption as long as sodium is sufficiently available from the previous meal.     

Onset of action of aqueous beclomethasone dipropionate nasal spray in seasonal allergic rhinitis

Beclomethasone dipropionate nasal spray is widely used in the treatment of seasonal allergic rhinitis; however, the time of onset of action has not been determined. This study assessed the onset of action, level of relief, and efficacy of beclomethasone nasal spray in patients with seasonal allergic rhinitis. In a double-blind, randomized, placebo-controlled, parallel-group, multicenter, 7-day study, symptomatic patients were administered two inhalations of beclomethasone dipropionate (n = 80) or placebo (n = 81) into each nostril twice daily. Patients assessed the onset of action and level of relief at 6, 24, and 48 hours and at days 3 and 7. Investigators evaluated symptoms at days 0, 3, and 7 and response to therapy at days 3 and 7. The difference in the cumulative number of patients reporting relief of symptoms was statistically significant in favor of beclomethasone dipropionate by hour 24 (P = 0.05). Patients in the beclomethasone dipropionate group experienced a greater level of relief than patients receiving placebo at hour 24, and improvement increased over the 7-day study compared with a decrease in relief in the placebo group. Beclomethasone dipropionate was significantly more effective than placebo in reducing symptoms (P < or = 0.02), and patients in the beclomethasone dipropionate group showed a more favorable response to treatment than did patients in the placebo group (P < 0.01). Adverse events were minor in both groups. Beclomethasone dipropionate nasal spray produced significant onset of relief of symptoms the first day of treatment; improvement was sustained and increased over the course of the study.     

Isolation and initial characterization of a newfound hantavirus from California

A fatal case of hantavirus pulmonary syndrome (HPS) in northern California prompted our attempt to isolate viruses from local rodents. From tissues of two deer mice, Peromyscus maniculatus, two hantaviruses (Convict Creek virus 107 and 74, CC107 and CC74) were established in cell culture. Viral antigens, proteins, and RNAs of the first and archetypical isolate (CC107) were examined, and portions of the medium (M) and small (S) genome segments of both isolates were sequenced. Antigenically, CC107 virus and the second isolate, CC74 virus, were more closely related to Puumala virus than Hantaan (HTN) virus, though distinct from both. Northern blots of viral RNAs showed the large and M segments of CC107 to be the same size as those of HTN virus, whereas the S segment was larger. Protein gels did not reveal CC107 to have a substantially larger nucleocapsid protein than HTN virus. Partial nucleotide sequence comparisons of CC107 and CC74 viruses revealed their M segments to be highly similar to one another, while their S segments differed by more than 10%. Nucleotide and deduced amino acid sequence comparisons showed the California isolates to be closely related to the newfound hantaviruses first detected in the Four Corners area and since incriminated in HPS through wide areas of the United States.