470 research outputs found
Cyclic AMP-dependent protein kinase and Ca2+-calmodulin stimulate the formation of polyphosphoinositjdes in a sarcoplasmic reticulum preparation of rabbit heart
AbstractA rabbit heart membrane fraction enriched in sarcoplasmic reticulum was incubated in a reaction mixture containing [Îł-32P]ATP. The catalytic subunit of cyclic AMP-dependent protein kinase enhanced the 32P-labelling of both phosphatidylinositol-4-phosphate and phosphatidylinositol-4,5-bisphosphate. Ca2+-calmodulin also increased the 32P-incorporation into both polyphosphoinositides. Upon SDS gel-electrophoretic analysis of the membrane proteins, phospholamban was found to be concurrently phosphorylated by the exogenous catalytic subunit as well as by an endogenous Ca2+-calmodulm-dependent protein kinase
EFFECT OF FERTILIZERS ON THE YIELD, PROTEIN CONTENT AND AMINO ACID COMPOSITION OF WINTER CEREALS
The effect of different fertilizers (nitrogen, phosphorus, potassium) and their combinations
on the yield, raw protein content and amino acid composition were studied in field
experiments. The levels of treatment were 200 kg/ha for nitrogen, 500-1000 kg/ha for
phosphorus and potassium. Winter rye, triticale and wheat cultivar were grown in two
subsequent years.
Nitrogen fertilization in all cases increased the yield of grains and the raw protein
content. The increase reached about 50% in average comparing with control samples grown
without adding nitrogen fertilizers. Although there are significant differences between the
different cereals studied, it can be generally stated that the increase in protein content is
connected with a decrease in the essential to non-essential amino acid ratio. The decrease
is higher if only nitrogen fertilizer is used and moderate if a combined treatment with
nitrogen, phosphorus and potassium fertilizer is applied
ABCC6 is a basolateral plasma membrane protein
RATIONALE:: ABCC6 plays a crucial role in ectopic calcification; mutations of the gene cause pseudoxanthoma elasticum and general arterial calcification of infancy. To elucidate the role of ABCC6 in cellular physiology and disease, it is crucial to establish the exact subcellular localization of the native ABCC6 protein. OBJECTIVE:: In a recent article in Circulation Research, ABCC6 was reported to localize to the mitochondria-associated membrane and not the plasma membrane. As the suggested mitochondrial localization is inconsistent with published data and the presumed role of ABCC6, we performed experiments to determine the cellular localization of ABCC6 in its physiological environment. METHODS AND RESULTS:: We performed immunofluorescent labeling of frozen mouse and human liver sections, as well as primary hepatocytes. We used several different antibodies recognizing human and mouse ABCC6. Our results unequivocally show that ABCC6 is in the basolateral membrane of hepatocytes and is not associated with the mitochondria, mitochondria-associated membrane, or the endoplasmic reticulum. CONCLUSIONS:: Our findings support the model that ABCC6 is in the basolateral membrane, mediating the sinusoidal efflux of a metabolite from the hepatocytes to systemic circulation. © 2013 American Heart Association, Inc
Induced ionization of small molecules: comparison of experiment with quantum and classical calculations
Resonant scattering of positronium as a quasifree electron
In order to clarify the physics underlying the observations of the electronlike behavior of positronium (Ps) and its resonant scattering from CO2, we have measured the Ps+N2 total cross section and found it also to exhibit significant structure. Analysis of the resonances reveals that Ps is distorted in the collisions and classical trajectory Monte Carlo calculations indicate that the electron is on average closer to the target than the positron, which may in turn bind resonantly to the ensuing temporary negative ion. This description of the nature of Ps resonances agrees with long-standing theoretical predictions
Interoperable AI: Evolutionary Race Towards Sustainable Knowledge Sharing
Article and Supplementary MaterialInternational audienceThe advancement and deployment of artificial intelligent agents brought numerous benefits in knowledge and data gathering and processing. However, one of the key challenges in deploying such agents in an open environment like the Web is their interoperability as they currently mostly run in silos. In this paper we report on a simulation and evaluation based on evolutionary agent-based modelling to empirically test how sustainable different strategies are for knowledge sharing in open multi-agent systems (MAS). Our results show the importance of translation-based approaches and the need for incentives to support these
Promoting positive development among refugee adolescents
Of the estimated 35.3âmillion refugees around the world (UNHCR, Figures at a Glance, 2022), approximately 50% are children under the age of 18. Refugee adolescents represent a unique group as they navigate developmental tasks in an unstable and often threatening environment or in resettlement contexts in which they often face marginalization. In addition to physiological, social, and psychological changes that mark adolescence, refugee youth often face traumatic experiences, acculturative stress, discrimination, and a lack of basic resources. In this consensus statement, we examine research on refugee adolescents' developmental tasks, acculturative tasks, and psychological adjustment using SuĂĄrez-Orozco and colleague's integrative risk and resilience model for immigrant-origin children and youth proposed by SuĂĄrez-Orozco et al. Finally, we discuss recommendations-moving from proximal to more distal contexts
Further characterization of the plasma membrane- and intracellular membrane-associated platelet Ca2+ transport systems
Ionization of small molecules induced byH+, He+, andN+projectiles: Comparison of experiment with quantum and classical calculations
We report the energy and angular distribution of ejected electrons from
CH and HO molecules impacted by 1 MeV H, He and 650 keV N
ions. Spectra were measured at different observation angles, from 2 eV to 2000
eV. The obtained absolute double-differential-electron-emission cross sections
(DDCS) were compared with the results of CTMC and CDW-EIS calculations. For the
bare H+ projectile both theories show remarkable agreement with the experiment
at all observed angles and energies. The CTMC results are in similarly good
agreement with the DDCS spectra obtained for impact by dressed He and N
ions, where screening effects and electron loss from the projectile gain
importance. The CDW-EIS calculations slightly overestimate the electron loss
for 1 MeV He impact, and overestimate both the target and projectile
ionization at low emitted electron energies for 650 keV N impact. The
contribution of multiple electron scattering by the projectile and target
centers (Fermi-shuttle) dominates the N-impact spectra at higher electron
energies, and it is well reproduced by the non-perturbative CTMC calculations.
The contributions of different processes in medium velocity collisions of
dressed ions with molecules are determined
The influence of long chain polyunsaturate supplementation on docosahexaenoic acid and arachidonic acid in baboon neonate central nervous system
BACKGROUND: Docosahexaenoic acid (DHA) and arachidonic acid (ARA) are major components of the cerebral cortex and visual system, where they play a critical role in neural development. We quantitatively mapped fatty acids in 26 regions of the four-week-old breastfed baboon CNS, and studied the influence of dietary DHA and ARA supplementation and prematurity on CNS DHA and ARA concentrations. METHODS: Baboons were randomized into a breastfed (B) and four formula-fed groups: term, no DHA/ARA (T-); term, DHA/ARA supplemented (T+); preterm, no DHA/ARA (P-); preterm and DHA/ARA supplemented (P+). At four weeks adjusted age, brains were dissected and total fatty acids analyzed by gas chromatography and mass spectrometry. RESULTS: DHA and ARA are rich in many more structures than previously reported. They are most concentrated in structures local to the brain stem and diencephalon, particularly the basal ganglia, limbic regions, thalamus and midbrain, and comparatively lower in white matter. Dietary supplementation increased DHA in all structures but had little influence on ARA concentrations. Supplementation restored DHA concentrations to levels of breastfed neonates in all regions except the cerebral cortex and cerebellum. Prematurity per se did not exert a strong influence on DHA or ARA concentrations. CONCLUSION: 1) DHA and ARA are found in high concentration throughout the primate CNS, particularly in gray matter such as basal ganglia; 2) DHA concentrations drop across most CNS structures in neonates consuming formulas with no DHA, but ARA levels are relatively immune to ARA in the diet; 3) supplementation of infant formula is effective at restoring DHA concentration in structures other than the cerebral cortex. These results will be useful as a guide to future investigations of CNS function in the absence of dietary DHA and ARA
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