Regulation of G protein-coupled receptor kinase 5 (GRK5) by actin

G protein-coupled receptor kinases (GRKs) initiate pathways leading to the desensitization of agonist-occupied G-protein-coupled receptors (GPCRs). Here we report that the cytoskeletal protein actin binds and inhibits GRK5. Actin inhibits the kinase activity directly, reducing GRK5-mediated phosphorylation of both membrane-bound GPCRs and soluble substrates. GRK5 binds actin monomers with a Kd of 0.6 microM and actin filaments with a Kd of 0. 2 microM. Mutation of 6 amino acids near the amino terminus of GRK5 eliminates actin-mediated inhibition of GRK5. Calmodulin has previously been shown to bind to the amino terminus of GRK5 (Pronin, A. N., and Benovic, J. L. (1997) J. Biol. Chem. 272, 3806-3812) and here we show calmodulin displaces GRK5 from actin. Calmodulin inhibits GRK5-mediated phosphorylation of GPCRs, but not soluble substrates such as casein. Thus in the presence of actin, calmodulin determines the substrate specificity of GRK5 by preferentially allowing phosphorylation of soluble substrates over membrane-bound substrates.     

On the economic selection of medium voltage cable sizes innonsinusoidal conditions

Selection of cable size in the nonsinusoidal conditions is only based on ampacity considerations without any attention to the cost of the losses that will be suffered in the cable life. Since the cost of these losses (fundamental plus harmonics) can assume significant values, the selection of a cross section higher than required for ampacity considerations can result in a large reduction of cost. This paper proposes a method which allows the optimal economic selection of medium-voltage cables in nonsinusoidal operating conditions; it takes into account the initial investment costs and the Joule losses costs, including the additional costs due to current harmonics. It employs simplified expressions similar to those adopted by the IEC Standard in sinusoidal conditions, being the harmonic presence taken into account by a proper definition of a harmonic loss factor and by the introduction of harmonic coefficients to be predicted. Numerical applications to medium-voltage cables are developed and discussed in order to show the sensitivity of the cable optimum size to variations in the coefficients that characterize the harmonic presence     

Recycling of dry and wet polyamide 6

Recycling of polycondensation polymers can give rise to secondary materials with good mechanical properties only if a careful drying is carried out before the melt reprocessing operations. The presence of humidity provokes the hydrolytic chain scission of the macromolecules and the consequent decrease of molecular weight and properties. In this work, the drying step was substituted by the addition of an antioxidant that is able to protect the macromolecules because it is the autioxidant is more prone to hydrolysis, thus removing the water from the melt. The mechanical properties of polyamide 6 reprocessed more times in wet conditions and in the presence of this stabilizer are even better than those obtained reprocessing the dry polyamide. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1899–1903, 2002     

Dietary factors and the risk of endometrial cancer

BACKGROUND: Endometrial cancer is associated with overweight, but little is known on its possible relationship with specific aspects of diet. METHODS: The relationship between dietary factors and the risk of endometrial cancer was investigated in a case-control study conducted in Switzerland and Northern Italy on 274 patients with histologically confirmed endometrial cancers and 572 control subjects admitted to the hospital for acute nongynecologic disorders that were not hormone related, metabolic, or neoplastic. RESULTS: Significant direct associations were observed with (1) the total energy intake (odds ratio [OR] for the highest versus the lowest consumption tertile = 2.7) and, after allowance for energy intake, (2) the frequency of consumption of most types of meats, eggs, beans or peas, added fats (OR for total added fat = 2.5), and sugar (OR = 2.5). Significant protection, of the order of 40-60% reduction in the highest versus the lowest consumption tertile, was conferred by elevated intake of most vegetables and fresh fruit and whole grain bread and pasta. This was reflected in the low OR for the highest tertiles of intake of beta-carotene and ascorbic acid (OR for the highest versus the lowest consumption tertile after allowance for energy intake = 0.5). CONCLUSIONS: The current study suggests that, aside from the predictable adverse effects of overeating and consequent overweight, some qualitative aspects of the habitual diet may also be associated with the risk of endometrial cancer, chiefly, the intake of animal proteins and fat (directly) and of fresh fruit, vegetables, and fibers (inversely).     

Authenticity and positivity strivings in marriage and courtship.

Proposed that married persons would want their spouses to see them as they saw themselves but that dating persons would want their relationship partners to evaluate them favorably. A survey of 176 married and dating couples tested these predictions. Just as married persons were most intimate with spouses whose evaluations verified their self-views, dating persons were most intimate with partners who evaluated them favorably. For married people with negative self-views, then, intimacy increased as their spouses evaluated them more negatively. Marriage apparently precipitates a shift from a desire for positive evaluations to a desire for self-verifying evaluations. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Magnet shaping to reduce induced voltage harmonics in PM machineswith surface mounted magnets

A simple methodology for reducing induced voltage harmonics in permanent magnet (PM) machines by selecting the appropriate magnet shape and dimensions is presented. The method, which uses a simplified analytical model of the magnetic circuit, is applied to three basic magnet shapes (rectangular, stepped, and trapezoidal), and can be extended to more complex geometries. The results of the analytical models are compared with results obtained from finite element analysis and with test results     

Brain neurotoxicity of Penitrem A: electrophysiological, behavioral and histopathological study

The neurotoxicity of Penitrem A (PA) in rats was assessed against neurophysiological, behavioral and histopathological parameters. Animals were acutely given intracerebroventricular (22-45 mg) or intraperitoneal injections (0.5-1.5 mg/kg) of PA. A typical trembling syndrome associated with PA was always noted. Depending on the dose administered, animals may convulse and eventually die (1-1.5 mg/kg). PA-induced transient alterations of the EEG involving an increase in the frequency and voltage of electrical activity recorded from the cerebral cortex. Hippocampal activity was not modified and some pathologic activities may be recorded at the thalamus. Generally these EEG alterations disappeared at d 3 after the injection and the animals progressively recovered. However in the most severe cases, neuromotor disturbances were maintained at d 7 (rotarod test). Coronal sections of the brain at the striatal, thalamic, hippocampal and pons levels mainly revealed that PA was able to induce dose related injuries in the cerebellum with massive degeneration of Purkinje cells and a significant vacuolization within the molecular layer. The neurotoxic mechanism remains unclear. Action of the mycotoxin on the cerebello-thalamo-cortical tract is discussed.