Response of mouse plantaris muscle to functional overload: comparison with rat and cat

Functional overload (FO) of a muscle by removing its synergists results in a compensatory hypertrophy of the muscle. However, the extent of the response appears to be dependent, at least in part, on the activity and/or loading levels of the muscle following surgery. Thus, differences in the inherent physical activity levels across species may be an important factor to consider. In the present study, the effects of 8 weeks of FO on the isometric mechanical properties of the plantaris of mice (highly active) were determined and the findings compared with the results from previous studies performed on the plantaris of rats (highly active) and cats (less active). FO resulted in approximately a doubling of the mass, the physiological cross-sectional area and the maximum tetanic tension per unit cross-sectional area, was similar in the plantaris of control and FO mice. Isometric twitch speed properties were unaffected, but the tension enhancement in response to an increase in the rate of stimulation showed the pattern of a "faster" muscle following FO. The fatigue resistance of the plantaris in FO mice was significantly higher than in control mice. Although the degree of hypertrophy that occurred in the mouse plantaris was similar to that observed after FO in rats and in cats that are exercised intermittently at high intensities, there were differences in the mechanical properties that may be related to the adaptability of species and/or the behavioral responses to the overload.     

Metabolic consequences of alcohol dependency

Alcohol dependency leads to a variety of biochemical adaptations and morphological changes which may be considered as either adaptive or destructive. This ranges from the utilization of ethanol as a metabolic fuel, to overt tissue and cellular damage, and may lead to increases in morbidity and mortality. Virtually every organ system is affected by either acute and chronic ethanol exposure and numerous metabolic pathways are altered. As a consequence of these wide ranging effects, it is extremely difficult to cover every aspect of alcohol toxicity in a single review. Instead, attention is focussed on selected areas, such as nutrition and protein metabolism in the liver and bone (and to a lesser extent, skeletal muscle and the gastrointestinal tract). The aim is to illustrate the numerous ways in which alcohol affects the body.     

Intellectual performance in multi-infarct dementia and Alzheimer''s disease a replication study

A comparative study was conducted to evaluate the efficacy of a metal or flexible plastic 8 mm cannula for artificial abortion by vacuum aspiration for patients at six to 10 weeks' gestation. Complication rates, amounts of retained tissue (obtained with a curette check), frequencies of cannula obstructions and procedure times were used as criteria for determining the efficacy of the two types of cannulae. Two physicians participated in the study: one was responsible for the preliminary examination and performance of the abortion, and the other physician, who was kept unaware of the type of cannula used, was responsible for patient care after completions of the abortion to the time of the follow-up visit. Paracervical block anesthesia was used in all cases. Differences in complication rates (controlled for gestational age) between groups of subjects aborted with either the metal or flexible plastic cannula were not significantly different (p less than .05). For both patient groups shock was the most frequently reported immediate complication (2.7% in the metal cannula group, 4,7% in the flexible plastic cannula group), and leukorrhea was the most frequently reported complication at the time of follow-up (3.3% metal, 5.3% flexible plastic). Amounts of retained tissue and frequency of cannulae obstruction were similar for both groups. Procedure times were also similar for both groups (means of 5.7 minutes and 5.5 minutes, respectively, for procedures performed with the metal and flexible plastic cannulae).     

Spasmogenic and potentiating actions of some amino acids on the guinea-pig myometrium

Ectothiorhodospira shaposhnikovii, Chromatium minutissimum and Thiocapsa roseopersicina were grown in the dark under anaerobic conditions on media containing glucose or fructose and organic acids. Their cell contained the following enzymes of the fructose diphosphate pathway: phosphofructokinase, fructose diphosphate aldolase, and 3-phosphoglyceraldehyde dehydrogenase. The activity of fructose diphosphate aldolase was higher in the cells grown in the dark than in the cells grown in the light. The same enzymes of the tricarboxylic acid cycle were found in the cells cultivated in the dark on media containing organic acids as in the cells grown in the light, though the activity of some enzymes was lower. Only the activity of isocitrate lyase increased in the cells cultivated in the dark on a medium containing acetate.