Pravastatin protection from cold stress in myocardium of rats

The aim of this research was to evaluate the possible protective effect of pravastatin on ultrastructural alterations induced by cold stress in the myocardium of rats. Sixteen EPM-Wistar rats (Rattus norvegicus albinus) were used and distributed into four groups: 1) control; 2) pravastatin; 3) cold stress, and 4) pravastatin + cold stress. A daily oral dose of 10 mg/kg of weight of pravastatin was administered to each rat in groups 2 and 4 for 15 days. The stress induced by cold was obtained by keeping the group 3 and 4 rats in a freezer at -8 degrees C for 4 hours. The animals were killed and the heart and fragments of the left ventricles (LV) were removed and processed prior to conducting electron microscopic analysis. The ultrastructural alterations in cardiomyocytes were quantified through the number of mitochondrial cristae pattern (cristalysis). The group subjected only to cold stress showed a significant increase in cristalysis (391.9) when compared with control group (42.0). In the cold stress and pravastatin pretreatment group, a statistically significant (96.9)*, P<0.05 cristalysis reduction was observed when compared with cold stress group. The mitochondrial cristalysis profiles of the control and pravastatin groups were 42.0 and 65.7, respectively. Cold stress induced a significant increase in the rate of mitochondrial cristalysis. In the group that received pravastatin and was exposed to cold stress, the drug protected the LV cardiomyocytes. This fact was confirmed by a reduction mitochondrial cristalysis pattern.     

Cardiovascular abnormalities in hyperthyroidism: a prospective Doppler echocardiographic study

PURPOSE: We investigated the prevalence and clinical importance of cardiovascular abnormalities in patients with hyperthyroidism. METHODS: All consecutive patients diagnosed with hyperthyroidism during a period of 24 months were included in the study. Medical history, complete physical examination results, electrocardiographic findings, laboratory determinations, and Doppler echocardiographic findings were obtained for all patients within 24 hours of diagnosis, and after euthyroidism had been achieved. Age- and sex-matched controls also were studied. RESULTS: Thirty-nine patients (mean [+/-SD] age, 52 +/- 20 years; range, 25 to 86 years; 72% women), and 39 age- and sex-matched controls, were included. Atrial fibrillation was present in 7 patients (18%). Moderate or severe mitral or tricuspid regurgitation, or both, were present in 9 patients (23%) and in only 1 control (3%; P= 0.01). Mean pulmonary arterial systolic pressure was 38 +/- 12 mm Hg (range, 17 to 64 mm Hg) in patients and 27 +/- 4 mm Hg (range, 19 to 37 mm Hg) in controls (P= 0.001). Sixteen patients (41%) and 1 control (3%) had pulmonary arterial systolic pressure >or=35 mm Hg. Left ventricular systolic dysfunction was detected in 1 patient. After correction of hyperthyroidism, a significant decrease in pulmonary arterial systolic pressure was observed, and the levels became similar to those of controls. CONCLUSION: In patients with hyperthyroidism, there is a high prevalence of pulmonary hypertension and atrioventricular valve regurgitation. These abnormalities usually correct after treatment for hyperthyroidism.     

Serum concentrations of insulin-like growth factor-I and insulin-like growth factor binding protein-3 in patients with chronic hepatitis

BACKGROUND: Insulin-like growth factor-I is a liver-derived humoral factor, which has important anabolic and metabolic actions and is predominantly bound by insulin-like growth factor binding protein-3. Low serum concentrations of both insulin-like growth factor-I and insulin-like growth factor binding protein-3 have been reported in patients with chronic liver disease, especially cirrhosis, but their conditions in chronic hepatitis are uncertain. The aim of this study was to evaluate the effect of chronic hepatitis on serum concentrations of insulin-like growth factor-I and insulin-like growth factor binding protein-3 and their association with hepatic inflammation activity and fibrosis. METHODS: Serum insulin-like growth factor-I and insulin-like growth factor binding protein-3 were measured by RIA (ng/ml) in 17 patients with mild to severe chronic viral hepatitis (12 chronic hepatitis C, 5 chronic hepatitis B) and 16 healthy subjects. The hepatic inflammation activity and the severity of fibrosis were evaluated using Desmet classification. RESULTS: Both insulin-like growth factor-I and insulin-like growth factor binding protein-3 levels did not correlate with inflammation activity, fibrosis or transaminase levels. In the chronic hepatitis group, insulin-like growth factor-I levels were significantly higher than the control group (mean, 263.8 +/- 27.33 versus 127.14 +/- 10.83 ng/ml, P < 0.001, respectively), whereas insulin-like growth factor binding protein-3 levels were significantly lower when compared with the controls (1643.47 +/- 60.68 versus 2728.87 +/- 284.61 ng/ml, P < 0.05, respectively). CONCLUSIONS: These results suggest that the concomitant states of serum insulin-like growth factor-I and insulin-like growth factor binding protein-3 levels in patients with chronic hepatitis may be different from cirrhotic patients and high serum IGF-I levels may be a specific finding of the stage of chronic hepatitis before developing cirrhosis.     

Mortality in Spain during the heat waves of summer 2003

The effect of the elevated temperatures on mortality experienced in Europe during the summer of 2003 was observed in several countries. This study, carried out in Spain, describes mortality between 1 June and 31 August and evaluates the effect of the heat wave on mortality. Observed deaths were obtained from official death registers from 50 provincial capitals. Observed deaths were compared with the expected number, estimated by applying a Poisson regression model to historical mortality series and adjusting for the upward trend and seasonality observed. Meteorological information was provided by the Instituto Nacional de Meteorologia (National Institute of Meteorology). Spain experienced three heat waves in 2003. The total associated excess deaths were 8% (43 212 observed deaths compared with 40 046 expected deaths). Excess deaths were only observed in those aged 75 years and over (15% more deaths than expected for the age group 75 to 84 and 29% for those aged 85 or over). This phenomenon (heat-associated excess mortality) is an emerging public health problem because of its increasing attributable risk, the aging of the Spanish population and its forecasted increasing frequency due to global warming. The implementation of alert and response systems based on monitoring of climate-related risks, emergency room activity and mortality, and strengthening the response capacity of the social and health services should be considered.     

Survival of colorectal cancer patients in relation to duration of symptoms and other prognostic factors

The effect of duration of symptoms and other prognostic factors on survival was studied by interview using a population-based sample of 154 colorectal cancer patients. The authors found that symptom durations of up to approximately one year before diagnosis had no effect on survival. In addition, it was found that the total number of symptoms was a statistically significant predictor of survival, although no single symptom had a significant effect. Stage, sex, and site also were found to be significant predictors of survival, whereas age, socioeconomic status, and other factors were not predictive. Research supported by NCI grant 2R18CA-16404. Work performed at the Fred Hutchinson Cancer Research Center.     

Influence of exercise order on repetition performance during low-intensity resistance exercise

The purpose of this study was to compare repetition maximum performance and ratings of perceived exertion during resistance exercise sessions conducted at a low intensity (i.e., 20 RM) and in different exercise orders. Twenty-one recreationally trained men performed two total body resistance exercise sessions in opposite orders; each exercise was performed for three sets with 2 minutes passive rest between sets and exercises. The results indicated significantly greater total repetitions for each exercise when performed near the beginning of a sequence and for the first set of each exercise, irrespective of the sequence. The ratings of perceived exertion, however, were not significantly different between sequences. In conclusion, repetition maximum performance for resistance exercise sessions conducted at a low intensity is significantly different based on exercise order. Therefore, when performing high repetitions with relatively low intensity loads, exercises should be prioritized based on individual needs and sports-specific movement patterns for greater volume and potential for the desired neuromuscular adaptations.