Lens Lesions in the Elk

During the period 1973–1976, eyes from 17 elks (Alces a. alces L) were examined, bilateral cataract being found in nine elks, and a cataract found in an additional elk, from which only one eye was submitted for examination. Macro-scopically, the lenses were more or less deformed and reduced in size, being milky white or brownish grey and shrunk, their surface uneven and granular. Microscopically, there was a marked fluid accumulation between the lens fibers and apparently also a swelling of the lens fibers. Proliferation and swelling of epithelial cells were observed as well. Etiological factors are discussed.     

Erythrocyte Aggregation in Athletes

Erythrocyte aggregation (examined microscopically in diluted blood), lipid and protein plasma profiles, and fibrinolytic activity were studied in endurance athletes. Division of the athletes into two subgroups by cluster analysis showed that a higher level of fitness was associated with a lower plasminogen activity; enhanced fibrinolysis; increased blood fluidity; lower fibrinogen, cholesterol, and triglyceride levels; a relatively low erythrocyte aggregation index; and high suspension stability of the blood. Fibrinogen was the key plasma factor determining erythrocyte aggregation. Its level was closely correlated with plasminogen activity. Discriminant analysis showed that most differences between groups of athletes were connected with plasminogen activity, the von Willebrand factor, and fibrinolytic activity.     

Physiological Criteria of Endurance in Athletes

The main bioenergetic qualities—the alactic anaerobic, glycolytic anaerobic, and aerobic potentials—are the main factors of endurance in athletes. These physiological properties may be estimated by three main parameters: power, capacity, and energy efficiency. The specific expression of endurance in athletes is determined by the ratio between these bioenergetic parameters. It has been found that the aforementioned criteria of endurance are expressed in different forms in the cases of critical modes of muscular activity and considerably affect performance in representatives of cyclic sports.     

Modeling the Impact of Lesions in the Human Brain

Lesions of anatomical brain networks result in functional disturbances of brain systems and behavior which depend sensitively, often unpredictably, on the lesion site. The availability of whole-brain maps of structural connections within the human cerebrum and our increased understanding of the physiology and large-scale dynamics of cortical networks allow us to investigate the functional consequences of focal brain lesions in a computational model. We simulate the dynamic effects of lesions placed in different regions of the cerebral cortex by recording changes in the pattern of endogenous (“resting-state”) neural activity. We find that lesions produce specific patterns of altered functional connectivity among distant regions of cortex, often affecting both cortical hemispheres. The magnitude of these dynamic effects depends on the lesion location and is partly predicted by structural network properties of the lesion site. In the model, lesions along the cortical midline and in the vicinity of the temporo-parietal junction result in large and widely distributed changes in functional connectivity, while lesions of primary sensory or motor regions remain more localized. The model suggests that dynamic lesion effects can be predicted on the basis of specific network measures of structural brain networks and that these effects may be related to known behavioral and cognitive consequences of brain lesions.     

Lesions of the frontal bone in American Indians

Over 1,400 adult skulls from archeological sites along the Atlantic Seaboard, in the Midwest and in the Southwest were examined for frontal lesions. A late prehistoric site in Delaware yielded the highest frequency. Next was a late prehistoric site in Illinois, but here the high frequency may reflect in part the collector's special interest in bone pathology. By contrast, the historic and early prehistoric sites yielded the lowest frequencies. Like Hooton and Snow, the only previous American investigators who have recorded frontal lesions in detail, the present authors agree that most of the occurrences in skulls from Archaic and early Pueblo sites are due to trauma. However, in the other groups studied most of the lesions appear to be inflammatory and to have a rather constant location on the frontal. Some are accompanied by lesions on the parietals and on certain long bones. After healing bone remodelling gradually eliminates much of the original disfigurement. Examples of lesions in different stages are illustrated. The appearance of some of the inflammatory lesions suggests syphilis, but satisfactory proof of this is not yet forthcoming. Hopefully, these findings will rekindle interest in the problem and stimulate further efforts to reach correct diagnoses.     

Rheological Properties of Blood in Athletes

Rheological properties of blood were studied in subjects with high physical activity (athletes). It was found that the whole blood viscosity decreased under conditions of relative rest. The use of the concept of hemorheological profiles made it possible to reveal different profiles in subjects exposed to different courses of training exercise. The relationship between the rheological properties of blood and the total work capacity in humans was established. The typical parameter of profiles in subjects with high physical activity was high erythrocyte deformability associated mainly with erythrocyte form and viscoelastic properties of its membrane.