Scaling of limb joint surface areas in anthropoid primates and other mammals

Recently it was reported that limb joint surface areas scale positively allometrically with body weight in anthropoid primates. This was attributed to the biomechanics of weight bearing: larger animals must require relatively larger joint surfaces to withstand relatively greater weight-related stresses on the joints. Our data on humeral and femoral geometry and joint surface areas in 73 species belonging to six mammalian orders (including primates) demonstrate that positive allometry of joint surface areas is not a general phenomenon for mammals and cannot have its basis among Anthropoidea in the biomechanics of weight bearing. We argue that, to the extent that positive allometric scaling of joint surface areas occurs in anthropoid primates, it is an artifact of differences in positional behaviour among distinct taxonomic groups that also happen to differ widely in body weight. Furthermore, we argue that, among mammals ranging in body size from sportive lemurs to giant pandas, functionally similar groups tend to exhibit: (1) linear dimensions (especially diameters and shaft circumferences) that scale in direct proportion to each other; and (2) joint surface areas that scale in direct proportion to the squares of linear dimensions and to the 2/3 power of body mass. In other words, limb bones of functionally similar animals fit the theoretical model of geometric similarity (or skeletal isometry). Differences in relative sizes of joint surface areas are related to differences in force transmission and movement potential among functionally distinct groups of animals.     

Comparison of Tissue Metal Concentrations in Zucker Lean, Zucker Obese, and Zucker Diabetic Fatty Rats and the Effects of Chromium Supplementation on Tissue Metal Concentrations

Diabetes results in several metabolic changes, including alterations in the transport, distribution, excretion, and accumulation of metals. While changes have been examined in several rat models of insulin resistance and diabetes, the metal ion concentrations in the tissues of Zucker lean, Zucker obese (an insulin resistance and early stage diabetes model), and Zucker diabetic fatty (ZDF, a type 2 diabetes model) have not previously been examined in detail. The concentration of Cu, Zn, Fe, Mg, and Ca were examined in the liver, kidney, heart and spleen, and Cr concentration in the liver and kidney of these rats were examined. Zucker obese rats have a reduction in the concentration of Cu, Zn, Fe, Mg in the liver compared to ZDF and/or lean Zucker rats, presumably as a result of the increased fat content of the liver of the obese rats. ZDF rats have increased concentrations of kidney Cu compared to the lean rats, while kidney Ca concentrations are increased in the Zucker obese rats. Spleen Fe concentrations are decreased in Zucker obese rats compared to the lean rats. No effects on metal concentrations in the heart were observed between the lean, obese, and ZDF rats, and no effects on Cr concentrations were identified. Cr(III) complexes have previously been shown to have beneficial effects on the signs of insulin resistance in Zucker obese and ZDF rats. The effects of daily gavage administration of chromium picolinate ([Cr(pic)₃]) (1 mg?Cr/kg body mass), CrCl₃ (1 mg?Cr/kg body mass), and Cr3 ([Cr₃O(propionate)₆(H₂O)₃]⁺) (33 μg and 1 mg?Cr/kg body mass) on metal concentrations in these tissues were examined. Treatment with CrCl₃ and Cr3, but not [Cr(pic)₃], at 1 mg?Cr/kg resulted in a statistically significant accumulation of Cr in the kidney of lean and obese but not ZDF rats but resulted in lowering the elevated levels of kidney Cu in ZDF rats, suggesting a beneficial effect on this symptom of type 2 diabetes.     

“Microbiological aging” by Mechnikov. How to interpret these ideas today?

Mechnikov’s hypothesis that the key to prolongation of life lies in the introduction of useful microflora to the gut was not proved. Any microflora needs nutrition and perceives the human body only as a nutrient substrate. Destruction of the basement membranes, that delimit the epithelium contacting with aggressive microbiological environment from the deeper parts of the body, can lead to chronic inflammatory diseases and aging of the skin as a consequence of invasion of microorganisms. At the ultrastructural level this has been shown by the example of prostatitis and skin aging changes. Coupled with the penetration of germs, a flux of immune cells may cause autoimmune reactions due to abrupt changes in the molecular design during intermembrane transport. Thus, the physiological process of macroorganism aging can be viewed as a consequence of its microbiological destruction.     

Combined treatment of persisting urogenital chlamydia infection with sumamed and interferon alfa]

The results of complex treatment of 235 patients with persisting urogenital chlamidial infection are presented. The treatment regime included immunotropic agent interferone alfa-alpha 2b and antibiotic azithromycin (Sumamed, "Pliva", Croatia) 1 g per day 3 times every 7 days. Chlamidial persistence diagnosis was performed by culture method (determination of small cytoplasmic inclusions), by the method of immune fluorescence and PCR. The treatment provided positive influence on immune status (amount of CD4+; HLA-DR+ cell and IgA level normalized after the treatment). In 3 months after the treatment only 2 cases of Chlamydia trachomatis infection recurrence were registered. Treatment efficacy achieves 94.8 per cent.     

Lee A. Fuiman and Robert G. Werner (eds.), Fisheries Science: The Unique Contributions of Early Life Stages

Reviews in Fish Biology and Fisheries -