Changes in calcium ion binding and characteristics of Na+, K+-ATPase functioning in erythrocytes in the presence of hypertension]

A greater amount of calcium is removed with the aid of EDTA from the erythrocyte membranes of patients with hypertensive disease than from erythrocytes of persons with a normal arterial blood pressure. When isotonic MgCl2 was used the amount of calcium removed from the erythrocytic membrane was equal in both groups. The activity of Na-K-ATP-ase in the membrane of reconstituted erythrocytes increased with the action of calcium ions in the patients with hypertensive disease only half as much as in healthy persons.     

Oxidative Posttranslational Modifications of Blood Plasma Proteins of Cosmonauts after a Long-Term Flight: Part II

Human Physiology - Oxidative damage to main cell components (DNA, lipids, and proteins) in the human body during a spaceflight (SF) is more intense than in normal conditions because of the...     

Reconstruction of Electric Discharge Patterns and Electrogenesis Mechanism in African Sharptooth Catfish Clarias gariepinus (Clariidae,Siluriformes)

Doklady Biological Sciences - Electrical discharges (EDs) in the African sharptooth catfish Clarias gariepinus were studied. Irregular monopolar EDs, lasting for 8–10 ms and longer, and more...     

The mechanobiology theory of the development of medical device-related pressure ulcers revealed through a cell-scale computational modeling framework

Biomechanics and Modeling in Mechanobiology - Pressure ulcers are localized sites of tissue damage which form due to the continuous exposure of skin and underlying soft tissues to sustained...     

Sorption of humic acids by bacteria

Capacity for sorption of humic acid (HA) from water solutions was shown for 38 bacterial strains. Isotherms of HA sorption were determined for the cells of 10 strains. The bonding strength between the cells and HA (k) and the terminal adsorption (Q _max) determined from the Langmuir equation for gram-positive and gram-negative bacteria were reliably different. Gram-positive bacteria sorbed greater amounts of HA than gram-negative ones (Q _max = 23 ± 10 and 5.6 ± 1.2 mg/m², respectively). The bonding strength between HA and the cells was higher in gram-negative bacteria than in gram-positive: k = 9 ± 5 and 3.3 ± 1.1 mL/mg, respectively.     

Optimization of training: New developments in safe strength training

The hypertrophic effect of strength training is known to be due to mechanical and metabolic stimuli. During exercises with the restricted blood supply of working muscles, i.e., under the conditions of intensified metabolic stress, the training effect may be achieved with much lower external loads (20% of one repetition maximum). The effects of 8 weeks of high-intensity (80–85% of one repetition maximum) strength training were compared to low-intensity (50% of one repetition maximum) training without relaxation. The high-intensity strength training resulted in higher increases in strength and size of the exercised muscles than training without relaxation. During high-intensity training, at the muscle cross section, an increase in the area occupied by type II fibers prevails; while, during training without relaxation, an increase in the area occupied by type I fibers prevails. An exercise session without relaxation leads to a more pronounced increase in the secretion of the growth hormone, insulin-like growth factor-1, and cortisol. The expression of gene regulating myogenesis (Myostatin) is changed in different ways after a high-intensity strength exercise session and after an exercise session without relaxation. Low-intensity strength training (50% of one repetition maximum) without relaxation is an efficient way for inducing increases of the strength and size of the trained muscles. This low-intensive type of training may be used in rehabilitation medicine, sports, and fitness.     

Chiroptical Properties of Bilirubin-Serum Albumin Binding Sites

Although the interactions between bilirubin and serum albumin are among the most studied serum albumin-ligand interactions, the binding-site location and the participation of bilirubin-serum albumin complexes in pathological and physiological processes are under debate. In this article, we have benefited from the chiral structure of bilirubin and used CD spectroscopy to characterize the structure of bilirubin bound to human and bovine serum albumins. We determined that in a phosphate buffer at pH 7.8 there are three binding sites in both human and bovine serum albumins. While the primary binding sites in human and bovine serum albumins bind bilirubin with P- and M-helical conformations, respectively, the secondary binding sites in both albumins bind bilirubin in the P-helical conformation. We have shown that the bonding of bilirubin to the serum albumin matrix is a more favorable process than the self-association of bilirubin under the studied conditions, with a maximum of three bound bilirubins per serum albumin molecule. Although bilirubin bound to the primary binding site has attracted the most attention, the presented results have documented the impact of the secondary binding sites which are relevant in the displacement reactions between BR and drugs and in the phenomena where bilirubin plays antioxidant, antimutagenic, and anti-inflammatory roles. Chirality 00:000000, 2013. © 2013 Wiley Periodicals, Inc.