Ar + H<Subscript>2</Subscript> Plasma Interacting with Lithium-Filled Capillary Porous Structure

Ar + H₂ plasma interacting with liquid lithium was carried out on a one-cathode linear plasma device (SCU-PSI). The lithium sample was covered with capillary porous structure (CPS). It is found that the electron temperature of applied plasma ranged from ~0–1 eV and electron density ranged from 0.1 × 10²⁰ to 1 × 10²⁰ m^?3. The experimental results indicate that a reduction in the electron temperature and the lithium evaporation is found as the percentage of H₂ increases When the ratio of argon and hydrogen keeps constant, the electron temperature and lithium evaporation increase with applied input power, respectively. The retention of hydrogen atoms in lithium surface results in reducing the lithium evaporation. The XRD analysis result shows that during plasma radiation no LiH is formed.     

Within-population craniometric variability of insular populations of deer mice, Peromyscus maniculatus, elucidated by landscape configuration

Within-population genetic variability of twelve insular and four mainland populations of deer mice ( Peromyscus maniculatus ) was assessed using craniometric characters, and compared to results previously obtained from RAPD data. An index of Craniometric Variance ( CVar ) was computed from pairwise distances among all specimens. Variations in CVar measures were then compared to landscape variables using a linear regression approach. Our results suggest that CVar decreases in presence of large number of a competitive species (the boreal redback vole, Clethrionomys gapperi ; r =−0.527, p <0.037) in deer mouse populations. Island remoteness ( r =−0.251, p <0.220) and the geometry of the bank opposite to each island ( r =−0.459, p <0.067) were marginally correlated with CVar , but the linear combination of these two variables, forming a composite isolation index, represented the major factor explaining the observed CVar ( r =−0.648, p <0.011). Using a multiple regression model, 76.3% of the CVar was explained by a combination of this isolation index and the competitors' abundance. These results suggest that taking into account landscape barriers as well as the dispersal behavior of small mammals might provide sounder ecological variables than geographical distances alone for predicting within-population genetic variability in a network of habitat patches.     

Depot-specific gene expression profiles during differentiation and transdifferentiation of bovine muscle satellite cells, and differentiation of preadipocytes

We report a systematic study of gene expression during myogenesis and transdifferentiation in four bovine muscle tissues and of adipogenesis in three bovine fat tissues using DNA microarray analysis. One hundred hybridizations were performed and 7245 genes of known and unknown function were identified as being differentially expressed. Supervised hierarchical cluster analysis of gene expression patterns revealed the tissue specificity of genes. A close relationship in global gene expression observed for adipocyte-like cells derived from muscle and adipocytes derived from intramuscular fat suggests a common origin for these cells. The role of transthyretin in myogenesis is a novel finding. Different genes were highly induced during the transdifferentiation of myogenic satellite cells and in the adipogenesis of preadipocytes, indicating the involvement of different molecular mechanisms in these processes. Induction of CD36 and FABP4 expression in adipocyte-like cells and adipocytes may share a common pathway.     

N-t-Butyl hydroxylamine regulates heat shock-induced apoptosis in U937 cells

Heat shock may increase oxidative stress due to increased production of reactive oxygen species and/or the promotion of cellular oxidation events. Therefore, compounds that scavenge reactive oxygen species may regulate heat shock-induced cell death. Recently, it has been shown that the decomposition product of the spin-trapping agent alpha-phenyl-N-t-butylnitrone, N-t-butyl hydroxylamine (NtBHA), mimics alpha-phenyl-N-t-butylnitrone and is much more potent in delaying reactive oxygen species-associated senescence. We investigated the protective role of NtBHA against heat shock-induced apoptosis in U937 cells. Upon exposure to heat shock, there was a distinct difference between the untreated cells and the cells pre-treated with 0.1 mM NtBHA for 2 h in regard to apoptotic parameters, cellular redox status, and mitochondrial function. Upon exposure to heat shock, NtBHA pre-treated cells showed significant inhibition of apoptotic features such as activation of caspase-3, up-regulation of Bax, and down-regulation of Bcl-2 compared to untreated cells. This study indicates that NtBHA may play an important role in regulating the apoptosis induced by heat shock, presumably through scavenging of reactive oxygen species.     

Reversible associative depression and nonassociative potentiation at a parallel fiber synapse

The electrosensory lobe (ELL) of mormyrid electric fish is one of several cerebellum-like sensory structures in fish that remove predictable features of the sensory inflow. This adaptive process obeys anti-Hebbian rules and appears to be mediated by associative depression at the synapses between parallel fibers and Purkinje-like cells of ELL. We show here that there is also a nonassociative potentiation at this synapse that depends only on the repeated occurrence of the EPSP. The depression can be reversed by the potentiation and vice versa. Finally, we show that the associative depression requires NMDA receptor activation, changes in postsynaptic calcium, and the occurrence of a postsynaptic dendritic spike within a few milliseconds following EPSP onset.     

Sodium Fluoride Affects Proliferation and Apoptosis Through Insulin-Like Growth Factor I Receptor in Primary Cultured Mouse Osteoblasts

Insulin-like growth factor-I receptor (IGF-IR) is important for maintaining proliferation and apoptosis in osteoblasts. However, the details about the effect of sodium fluoride supplementation on primary osteoblast cultures on mediating IGF-IR expression are still not well-known. In this study, we used mouse osteoblasts to examine the impact of sodium fluoride on the proliferation and apoptosis; the cells were treated with IGF-IR small interfering RNA (or left untreated) and subsequently divided into a control group and six experimental groups, which were exposed to different concentrations of NaF (10(-6), 10(-5), 10(-4), 10(-3), 5?×?10(-3), and 10(-2)?mol/L) for analysis at 48?h. In particular, we examined cell proliferation, apoptosis, IGF-IR messenger RNA, and protein expression levels of the various cell groups. In summary, our findings suggest that the administration of NaF affects the expression of IGF-IR in mouse osteoblasts, contributing to the proliferation and apoptosis induced by fluoride.