The effects of a 7-day period of daily physical stress (chasing until exhaustion) on the beta-adrenergic response of the rainbow trout (Oncorhynchus mykiss) red blood cell (rbc) were examined in vitro. Physical stress was associated with pronounced increases in the circulating levels of the catecholamine hormones (adrenaline and noradrenaline) measured on days 1, 3 and 7 of the stress regime. A...

Ca(2+)/calmodulin kinase II (CaMKII) plays an important role in cardiac contractility and the development of heart failure. Although stimulation of beta(1)-adrenergic receptors (ARs) leads to an increase in CaMKII activity, the molecular mechanism by which beta(1)-ARs activate CaMKII is not completely understood. In this study, we show the requirement for the beta(1)-AR regulatory protein beta-...

The effects of efonidipine hydrochloride (efonidipine), a dihydropyridine calcium antagonist, on the cholesterol ester metabolism induced by beta-migrating very low density lipoprotein (beta-VLDL) in J774 macrophages were studied. The cholesteryl ester content in the macrophages was increased by incubation with beta-VLDL, and the increase was inhibited by efonidipine. Oleic acid incorporation i...

Transfection of U937 and THP-1 cells with a recombinant plasmid, pIL1(4.0kb)-CAT, containing 4 kb of the interleukin 1 beta (IL-1 beta) gene upstream regulatory sequence resulted in inducer-dependent expression of chloramphenicol acetyltransferase activity. Treatment of the transfected cells with various combinations of the inducers lipopolysaccharide, phorbol myristate acetate, and dibutyryl c...

Histamine, beta-adrenergic amines, and prostaglandins inhibited hemolytic plaque formation by splenic leukocytes from immunized mice. The same agents had previously been shown to prevent both the IgE-mediated release of histamine from human basophils and the immunologically specific cytolytic activity of murine lymphocytes, through stimulation of the production of cyclic AMP in leukocytes. We t...

We used electronic circular dichroism (CD) and UV resonance Raman (UVRR) spectroscopy at 204 nm excitation to examine the temperature dependence of conformational changes in cyclic and linear elastin peptides. We utilize CD spectroscopy to study global conformation changes in elastin peptides, while UVRR is utilized to probe the local conformation and hydrogen bonding of Val and Pro peptide bon...

This study investigated the effect of mechanical load on human mesenchymal stem cell (hMSC) differentiation under different exogenous transforming growth factor-beta1 (TGF-beta(1)) concentrations (0, 1 or 10 ng/ml).The role of the TGF-beta signalling pathway in this process was also studied. Human MSCs were seeded into fibrin-biodegradable polyurethane scaffolds at a cell density of 5 x 10(6) c...

The initial action of cyclodextrin glucanotransferase (CGTase, EC 2.4.1.19) from an alkalophilic Bacillus sp. A2-5a on amylose was investigated. Synthetic amylose was incubated with purified CGTase then terminated in the very early stage of the enzyme reaction. When the reaction mixture was treated with glucoamylase and the resulting glucoamylase-resistant glucans were analyzed with high perfor...

The properties and regulation of beta-lactamases produced by certain R factors derived from ampicillin-resistant strains of Escherichia coli and Klebsiella were characterized. beta-Lactamase activity was determined by the acidimetric method with phenol red as indicator. The sensitivity of this assay was increased by employing phosphate buffer at a final concentration of 0.4 mm; as little as 0.0...