bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasma membrane insertion of TRPC5 channels contributes to the cholinergic plateau potential in hippocampal CA1 pyramidal neurons
Authors: Tai Chao , Hines Dustin J. , Choi Hyun B. , MacVicar Brian A. 
Published: June 2010

AbstractIn cultured hippocampal neurons, transient receptor potential 5 (TRPC5) channels are translocated and inserted into plasma membranes of hippocampal neurons to generate nonselective cation (NSC) currents. We investigated whether TRPC5 channel translocation also contributes to the generation of NSC currents underlying the afterdepolarizations and plateau potentials (PPs) in hippocampal pyramidal cells that are induced by muscarinic receptor activation. Using a biotinylation assay to quantify the change in surface membrane proteins in acute hippocampal slices, we found that muscarinic stimulation significantly enhanced the levels of TRPC5 protein on the membrane surface but not those of TRPC1 or TRPC4 channels. We then investigated the pharmacological sensitivity of the cation current observed during muscarinic stimulation to determine if a component could be due to TRPC5 channels. The TRPC channel antagonists 2‐APB and SKF96365 strongly depressed the generation of PPs, the underlying tail currents (Itail) and the associated dendritic Ca2+ influx induced by muscarinic receptor activation in pyramidal neurons. High intracellular concentrations of ATP, which specifically inhibit TRPC5 channels, depressed Itail. In addition, pretreatment with the calmodulin (CaM) inhibitor W‐7, which depresses recombinant TRPC5 currents, inhibited both the cation current (Itail) and the surface insertion of TRPC5 channels. Finally, the phosphatidylinositide 3‐kinase (PI3K) inhibitor wortmannin, which blocks translocation of TRPC5 channels in cell culture, also inhibited both the Itail and the surface insertion of TRPC5 channels. Therefore, we conclude that insertion of TRPC5 channels contributes to the generation of the prolonged afterdepolarizations following muscarinic stimulation. This altered plasma membrane expression of TRPC5 channels in pyramidal neurons may play an important role in the generation of prolonged neuronal depolarization and bursting during the epileptiform seizure discharges of epilepsy. © 2010 Wiley‐Liss, Inc.
Volume of a liquid drop detaching from a sphere
Authors: Katoh Kenji , Iyota Hiroyuki , Inoue Tamotsu , Tsujino Tomoya 
Published: June 2010

AbstractA theoretical and experimental study is conducted to investigate the detached volume from a pendant drop on the surface of a sphere. Observation of drop detachment by high‐speed video camera reveals that the movement of the upper part of the neck of the drop is quite slow compared to that of the detaching lower part. The surface profile of the upper part was calculated approximately as a static problem using the axisymmetric Laplace equation. Using the drop profile, the system energy, including the work done by the solid–liquid wetting behavior, was calculated. Based on the condition of minimum energy, the volume of the detached part V was calculated. The volume V increases with the sphere diameter and approaches the value for the pendant drop attached to a plate. In addition, V is strongly dependent on the wettability between the sphere and the liquid and decreases with the receding contact angle. The detached volume of the water drop was measured for spheres of porous brick of various diameters. The experimental and theoretical results were found to be in good agreement. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20305
Molecular Dynamics Study on Thermal Conductivity of Carbon Nanotubes
Authors: Hou Quan‐Wen , Cao Bing‐Yang , Guo Zeng‐Yuan 
Published: June 2010

AbstractThe thermal conductivity of a (5, 5) carbon nanotube at room temperature is studied by non‐equilibrium molecular dynamics simulations. The thermal conductivity increases from 30 W/(m·K) to 1000 W/(m·K) as the tube length increases from 6 nm to 4 µm. It is proportional to the tube length when the tube length is less than 40 nm, which indicates that the heat conduction is in the ballistic transport regime. The thermal conductivity relates to the tube length by an exponential function as the tube length increases, and the length dependence exponent decreases and approaches zero, which indicates that the phonon transport changes from the ballistic regime to the diffusive regime. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; 39(7): 455–459, 2010; Published online in Wiley Online Library (wileyOnlinelibrary.com). DOI 10.1002/htj.20311
Overexpression of carbonic anhydrase XII in tissues from resectable non‐small cell lung cancers is a biomarker of good prognosis
Authors: Ilie Marius I. , Hofman Véronique , Ortholan Cécile , Ammadi Reda El , Bonnetaud Christelle , Havet Katia , Venissac Nicolas , Mouroux Jerôme , Mazure Nathalie M. , Pouysségur Jacques , Hofman Paul 
Published: June 2010

AbstractThe pattern of protein expression in tumors is under the influence of nutrient stress, hypoxia and low pH, which determines the survival of neoplastic cells and the development of tumors. Carbonic anhydrase XII (CAXII) is a transmembrane enzyme that catalyzes the reversible hydration of cell‐generated carbon dioxide into protons and bicarbonate. Hypoxic conditions activate its transcription and translation and enhanced expression is often present in several types of tumors. The aim of our study was to assess the prognostic significance of CAXII tumor tissues expression in patients with NSCLC. Five hundred fifty‐five tumors were immunostained for CAXII on tissue microarrays (TMA) and the results were correlated with clinicopathological parameters and outcome of patients. CAXII overexpression was present in 105/555 (19%) cases and was associated with tumors of lower grade (p = 0.015) and histological type (p < 0.001), being significantly higher in squamous cell carcinoma. High CAXII expression correlated with better overall and disease‐specific survival of patients with resectable NSCLC in univariate (p < 0.001) and multivariate survival analyses (p < 0.001). In conclusion, this is the first study demonstrating that a high CAXII tumor tissue expression evaluated on TMAs is related to a better outcome in a large series of patients with resectable NSCLC.
Silibinin attenuates cardiac hypertrophy and fibrosis through blocking EGFR‐dependent signaling
Authors: Ai Wen , Zhang Yan , Tang Qi‐Zhu , Yan Ling , Bian Zhou‐Yan , Liu Chen , Huang He , Bai Xue , Yin Lu , Li Hongliang 
Published: June 2010

AbstractCardiac hypertrophy is a major determinant of heart failure. The epidermal growth factor receptor (EGFR) plays an important role in cardiac hypertrophy. Since silibinin suppresses EGFR in vitro and in vivo, we hypothesized that silibinin would attenuate cardiac hypertrophy through disrupting EGFR signaling. In this study, we examined this hypothesis using neonatal cardiac myocytes and fibroblasts induced by angiotensin II (Ang II) and animal model by aortic banding (AB) mice. Our data revealed that silibinin obviously blocked cardiac hypertrophic responses induced by pressure overload. Meanwhile, silibinin markedly reduced the increased generation of EGFR. Moreover, these beneficial effects were associated with attenuation of the EGFR‐dependent ERK1/2, PI3K/Akt signaling cascade. We further demonstrated silibinin decreased inflammation and fibrosis by blocking the activation of NF‐κB and TGF‐β1/Smad signaling pathways in vitro and in vivo. Our results indicate that silibinin has the potential to protect against cardiac hypertrophy, inflammation, and fibrosis through blocking EGFR activity and EGFR‐dependent different intracellular signaling pathways. J. Cell. Biochem. 110: 1111–1122, 2010. Published 2010 Wiley‐Liss, Inc.
Recent advances in understanding the mechanisms of osteoclast precursor fusion
Authors: Oursler Merry Jo 
Published: June 2010

AbstractBone marrow macrophages fuse on the bone surface to form multinucleated osteoclasts that then organize to efficiently resorb bone. Many, if not all, of the stages of macrophage fusion involve cytoskeletal components that reorganize the cells. Recruitment may involve chemotactic responses to bone matrix protein and calcium ion gradients and/or chemokine production by bone forming osteoblasts. The roles of integrins vary, depending on the particular subunits with some interfering with fusion and others having a participatory role. RANKL is essential for fusion and many identified modulators of fusion influence RANKL signaling pathways. Tetraspanins have been implicated in fusion of macrophages and myoblasts, but differences in impacts exist between these two cell types. Macrophage recruitment to apoptotic cells prior to their engulfment is driven by the exposed phospholipids on the external surface of the apoptotic cells and there is evidence that this same identification mechanism is employed in macrophage fusion. Because loss of cadherin or ADAM family members suppresses macrophage fusion, a crucial role for these membrane glycoproteins is evident. The Ig membrane glycoprotein superfamily members CD200 and MFR/SIRPα are involved in macrophage fusion, although their influences are unresolved. Differential screenings have identified the structurally related membrane proteins DC‐STAMP and OC‐STAMP as required components for fusion and the contributions to fusion remain active areas of investigation. While many of the key components involved in these processes have been identified, a great deal of work remains in resolving the precise processes involved and the interactions between key contributors to multinucleated osteoclast formation. J. Cell. Biochem. 110: 1058–1062, 2010. Published 2010 Wiley‐Liss, Inc.
AP2α is essential for MUC8 gene expression in human airway epithelial cells
Authors: Moon Uk Yeol , Kim Chang‐Hoon , Choi Jae Young , Kim Yoon‐Ju , Choi Yeon Ho , Yoon Ho‐Geun , Kim Hyeyoung , Yoon Joo‐Heon 
Published: June 2010

AbstractMucins are high molecular weight proteins that make up the major components of mucus. Hypersecretion of mucus is a feature of several chronic inflammatory airway diseases. MUC8 is an important component of airway mucus, and its gene expression is upregulated in nasal polyp epithelium. Little is known about the molecular mechanisms of MUC8 gene expression. We first observed overexpression of activator protein‐2alpha (AP2α) in human nasal polyp epithelium. We hypothesized that AP2α overexpression in nasal polyp epithelium correlates closely with MUC8 gene expression. We demonstrated that phorbol 12‐myristate 13‐acetate (PMA) treatment of the airway epithelial cell line NCI‐H292 increases MUC8 gene and AP2α expression. In this study, we sought to determine which signal pathway is involved in PMA‐induced MUC8 gene expression. The results show that the protein kinase C and mitogen‐activating protein/ERK kinase (MAPK) pathways modulate MUC8 gene expression. PD98059 or ERK1/2 siRNA and RO‐31‐8220 or PKC siRNA significantly suppress AP2α as well as MUC8 gene expression in PMA‐treated cells. To verify the role of AP2α, we specifically knocked down AP2α expression with siRNA. A significant AP2α knock‐down inhibited PMA‐induced MUC8 gene expression. While dominant negative AP2α decreased PMA‐induced MUC8 gene expression, overexpressing wildtype AP2α increased MUC8 gene expression. Furthermore, using lentiviral vectors for RNA interference in human nasal polyp epithelial cells, we confirmed an essential role for AP2α in MUC8 gene expression. From these results, we concluded that PMA induces MUC8 gene expression through a mechanism involving PKC, ERK1/2, and AP2α activation in human airway epithelial cells. J. Cell. Biochem. 110: 1386–1398, 2010. © 2010 Wiley‐Liss, Inc.
Imatinib targets PDGF signaling in melanoma and host smooth muscle neighboring cells
Authors: Pirraco Ana , Coelho Pedro , Rocha Ana , Costa Raquel , Vasques Luísa , Soares Raquel 
Published: June 2010

AbstractIn previous in vitro studies, we showed that imatinib abrogated platelet‐derived growth factor receptor α (PDGFRα) signaling, disrupting both breast cancer and smooth muscle cells (SMC). PDGF is also a powerful mitogen for neural crest origin cells like melanocytes. The purpose of the present study was to evaluate the effect of imatinib on melanoma growth and in angiogenesis, with emphasis to the involvement in PDGF signaling. B16 melanoma cells incubation with 5 µM (IC50) imatinib resulted in a significant reduction in cell proliferation and migration. Apoptosis, however, was not significantly affected. Phosphorylated‐PDGFRα expression was decreased in B16 lysates. In a mouse model of B16 melanoma, intraperitoneal administration of imatinib at early day light significantly decreased tumor growth. These findings were corroborated by a highly significant reduction in cell proliferation and increase in apoptosis in melanoma tumors. This was accompanied by a decrease in microvessel density and in the number of SMC‐presenting vessels. Imatinib further inhibited PDGFRα expression and activity, as confirmed by the down‐regulation of downstream Erk signaling pathway. Altogether, this study demonstrates that besides targeting tumor cells, imatinib also prevents vascular integrity. The current study provides evidence that the paracrine crosstalk between tumor cells and host neighboring cells is crucial for the elucidation of imatinib effects. In addition, the fact that this molecule targets vascular support cells further enlarges its therapeutic purpose to a wide range of vasculoproliferative pathologies. J. Cell. Biochem. 111: 433–441, 2010. © 2010 Wiley‐Liss, Inc.
Association of home visitors' and mothers' attachment style with family engagement
Authors: McFarlane Elizabeth , Burrell Lori , Fuddy Loretta , Tandon Darius , Derauf D. Christian , Leaf Philip , Duggan Anne 
Published: June 2010

AbstractFamily engagement in home visiting (HV) is challenging. This study related attachment security of home visitors (n=48) and mothers (n=328) to family engagement in an HV program to prevent child maltreatment. Attachment security was assessed by using the Attachment Style Questionnaire to measure attachment anxiety and attachment avoidance. Family engagement was defined as receipt of a high dose of visits and home visitor response to intimate partner violence (IPV) and poor maternal mental health as measured via record review and by maternal report of trust in the home visitor.Home visitors had lower attachment anxiety and avoidance than mothers. Families were likely to receive a high dose of services if either the mother or home visitor was high on attachment anxiety. Home visitors high on attachment anxiety were less likely to respond to IPV and poor maternal mental health; home visitors high on attachment avoidance were more likely to respond to these issues. Mothers with high attachment anxiety were less trusting of highly anxious home visitors and more trusting of avoidant home visitors. HV programs should consider the influence of both home visitor and maternal attachment style on family engagement. © 2010 Wiley Periodicals, Inc.
Early parenthood in a community context: neighborhood conditions, race–ethnicity, and parenting stress
Authors: M. Franco Lydia , J. Pottick Kathleen , Huang Chien‐Chung 
Published: June 2010

AbstractResearch has highlighted the role of intrapersonal and family characteristics on stress, but less attention has been paid to the potential influence of the community context and racial‐ethnic differences in early parental experiences. Using an ecological model, this study examines the impact of neighborhood‐level social disorder and social cohesion on parenting stress and whether this is universal across mothers of different race–ethnicities in a sample of mothers of young children in large U.S. cities. Study findings show that neighborhood context is significantly associated with parenting stress and minority parents experience less stress than White parents in higher‐disordered neighborhoods. Findings highlight the need to improve community conditions, social support, and resources to reduce parenting stress. © 2010 Wiley Periodicals, Inc.
Structural and biochemical correlates of Na+,K+‐ATPase driven ion uptake across the posterior gill epithelium of the true freshwater crab, Dilocarcinus pagei (Brachyura, Trichodactylidae)
Authors: Furriel Rosa Prazeres Melo , Firmino Kelly Cristina Silva , Masui Douglas Chodi , Faleiros Rogério Oliveira , Torres Antonio Hernandes , McNamara John Campbell 
Published: June 2010

AbstractTo better comprehend the structural and biochemical underpinnings of ion uptake across the gills of true freshwater crabs, we performed an ultrastructural, ultracytochemical and morphometric investigation, and kinetically characterized the Na+,K+‐ATPase, in posterior gill lamellae of Dilocarcinus pagei. Ultrastructurally, the lamellar epithelia are markedly asymmetrical: the thick, mushroom‐shaped, proximal ionocytes contain elongate mitochondria (41% cell volume) associated with numerous (≈14 µm2 membrane per µm3 cytoplasm), deep invaginations that house the Na+,K+‐ATPase, revealed ultracytochemically. Their apical surface is amplified (7.5 µm2 µm−2) by stubby evaginations whose bases adjoin mitochondria below the subcuticular space. The apical membrane of the thin, distal ionocytes shows few evaginations (1.6 µm2 µm−2), each surrounding a mitochondrion, abundant in the cytoplasm below the subcuticular space; basolateral invaginations and mitochondria are few. Fine basal cytoplasmic bridges project across the hemolymph space, penetrating into the thick ionocytes, suggesting ion movement between the epithelia. Microsomal Na+,K+‐ATPase specific activity resembles marine crabs but is ≈5‐fold less than in species from fluctuating salinities, and freshwater shrimps, suggesting ion loss compensation by strategies other than Na+ uptake. Enzyme apparent K+ affinity attains 14‐fold that of marine crabs, emphasizing the relevance of elevated K+ affinity to the conquest of fresh water. Western blotting and biphasic ouabain inhibition disclose two α‐subunit isoforms comprising distinct functional isoenzymes. While enzyme activity is not synergistically stimulated by NH and K+, each increases affinity for the other, possibly assuring appropriate intracellular K+ concentrations. These findings reveal specific structural and biochemical adaptations that may have allowed the establishment of the Brachyura in fresh water. J. Exp. Zool. 313A:508–523, 2010. © 2010 Wiley‐Liss, Inc.
Optimization of enzyme–substrate pairing for bioluminescence imaging of gene transfer using Renilla and Gaussia luciferases
Authors: Kimura Takahiro , Hiraoka Kei , Kasahara Noriyuki , Logg Christopher R. 
Published: June 2010

AbstractBackgroundBioluminescence imaging (BLI) permits the non‐invasive quantification and localization of transduction and expression by gene transfer vectors. The tendency of tissue to attenuate light in the optical region, however, limits the sensitivity of BLI. Improvements in light output from bioluminescent reporter systems would allow the detection of lower levels of expression, smaller numbers of cells and expression from deeper and more attenuating tissues within an animal.MethodsWith the goal of identifying substrates that allow improved sensitivity with Renilla luciferase (RLuc) and Gaussia luciferase (GLuc) reporter genes, we evaluated native coelenterazine and three of its most promising derivatives in BLI of cultured cells transduced with retroviral vectors encoding these reporters. Of the eight enzyme–substrate pairs tested, the two that performed best were further evaluated in mice to compare their effectiveness for imaging vector‐modified cells in live animals.ResultsIn cell culture, we observed striking differences in luminescence levels from the various enzyme–substrate combinations and found that the two luciferases exhibited markedly distinct abilities to generate light with the substrates. The most effective pairs were RLuc with the synthetic coelenterazine derivative ViviRen, and GLuc with native coelenterazine. In animals, these two pairs allowed similar detection sensitivities, which were eight‐ to 15‐fold higher than that of the prototypical RLuc‐native coelenterazine combination.ConclusionsSubstrate selection can dramatically influence the detection sensitivity of RLuc and GLuc and appropriate choice of substrate can greatly improve the performance of reporter genes encoding these enzymes for monitoring gene transfer by BLI. Copyright © 2010 John Wiley & Sons, Ltd.
Density functional theory and RRKM calculations of decompositions of the metastable E‐2,4‐pentadienal molecular ions
Authors: Solano Espinoza Eduardo A. , Vallejo Narváez Wilmer E. 
Published: June 2010

AbstractThe potential energy profiles for the fragmentations that lead to [C5H5O]+ and [C4H6]+• ions from the molecular ions [C5H6O]+• of E‐2,4‐pentadienal were obtained from calculations at the UB3LYP/6‐311G + + (3df,3pd)//UB3LYP/6‐31G(d,p) level of theory. Kinetic barriers and harmonic frequencies obtained by the density functional method were then employed in Rice–Ramsperger–Kassel–Marcus calculations of individual rate coefficients for a large number of reaction steps. The pre‐equilibrium and rate‐controlling step approximations were applied to different regions of the complex potential energy surface, allowing the overall rate of decomposition to be calculated and discriminated between three rival pathways: CH bond cleavage, decarbonylation and cyclization. These processes should have to compete for an equilibrated mixture of four conformers of the E‐2,4‐pentadienal ions. The direct dissociation, however, can only become important in the high‐energy regime. In contrast, loss of CO and cyclization are observable processes in the metastable kinetic window. The former involves a slow 1,2‐hydrogen shift from the carbonyl group that is immediately followed by the formation of an ion‐neutral complex which, in turn, decomposes rapidly to the s‐trans‐1,3‐butadiene ion [C4H6]+•. The predominating metastable channel is the second one, that is, a multi‐step ring closure which starts with a rate‐limiting cis—trans isomerization. This process yields a mixture of interconverting pyran ions that dissociates to the pyrylium ions [C5H5O]+. These results can be used to rationalize the CID mass spectrum of E‐2,4‐pentadienal in a low‐energy regime. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of surface roughness on TM modes in rectangular waveguide
Authors: Chen Juan , Huang Binke , Jiang Wanshun 
Published: June 2010

AbstractBy using a rigorous numerical technique that is applicable to calculations of modes in waveguides for the TM case, the effects of the periodic rectangular, triangular, sinusoidal, and Gaussian random rough surface on the rectangular waveguide are discussed. The effects of the parameters of the roughness on the mode cutoff frequencies and field distribution are considered, including the height, width, and period of the grooves, the standard deviation of height and correlation length of the Gaussian roughness. Copyright © 2010 John Wiley & Sons, Ltd.