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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2007.06.003 Byline: Eun-Jung Jin (a), Young-Ae Choi (a), Eui Kyun Park (b), Ok-Sun Bang (c), Shin-Sung Kang (a)(d) Keywords: Chondrogenesis; Condensation; FAK; Fibronectin; Integrin; MMP-2; p38MAPK Abstract: Matrix metalloprotease-2 (MMP-2) has the capacity to degrade cartilage extracellular matrix molecules, the turnover of which is an essential event in chondrogenesis. Here, we investigated the functional role of MMP-2 in chondrogenesis of leg bud mesenchymal cells. Small interference RNA (siRNA)-mediated knockdown of mmp-2 promoted precartilage condensation and chondrogenesis. Treatment with bafilomycin A1, an MMP-2 activator, or GM6001, an MMP inhibitor, at the pre-condensation stage resulted in the inhibition or promotion of chondrogenesis, respectively. By comparison, treatment at the post-condensation stage had little or no effect on chondrogenesis. These results indicate that MMP-2 is involved in the regulation of cell condensation. Inhibition of MMP-2 activity by mmp-2 specific siRNA increased the protein level of fibronectin, and integrins [alpha]5 and [beta]1. The interaction between focal adhesion kinase (FAK) and integrin [beta]1 leading to tyrosine phosphorylation of FAK was also enhanced. Moreover, inactivation of p38MAPK down-regulated the level of MMP-2 mRNA and activity, and increased mesenchymal cell condensation in parallel with enhanced phosphorylation of FAK. Taken together, our data indicate that MMP-2 mediates the inhibitory signals of p38MAPK during mesenchymal cell condensation by functioning as a negative regulator of focal adhesion activity regulated by FAK via interactions with fibronectin through integrin [beta]1. Author Affiliation: (a) Department of Biology, College of Natural Sciences (BK21), Daegu 702-701, Korea (b) Department of Pathology and Regenerative Medicine, School of Dentistry, Kyungpook National University, Daegu 702-701, Korea (c) Department of Medical Research, Korea Institute of Oriental Medicine, Daejeon, 305-811, Korea (d) Daegu Center, Korea Basic Science Institute, Daegu 702-701, Korea Article History: Received 30 November 2006; Revised 31 May 2007; Accepted 5 June 2007

We aimed to investigate the incidence rate and risk factors of medical device-related pressure injuries (MDRPIs) among patients undergoing prone position spine surgery. This was a prospective observational study of 147 patients who underwent spine surgery in an orthopaedic hospital in Korea. The incidence of MDRPI according to intrinsic and extrinsic factors was assessed using the independent t-, χ2 -, or Fisher's exact tests. A logistic regression analysis was performed exclusively for MDRPI areas with an incidence rate >5%. The mean incidence rate of overall MDRPI was 27.4%, while that of MDRPI by Wilson frame, bi-spectral index, and endotracheal tube (ETT) was 56.5%, 52.4%, and 9.5%, respectively. The risk factors under Wilson frame were operation time and body mass index classification. Compared to their normal weight counterparts, those who were underweight, overweight, and obese had a 46.57(95% CI: 6.37–340.26), 3.96 (95% CI: 1.13–13.86), and 5.60 times (95% CI: 1.62–19.28) higher risk of developing MDRPI, respectively. The risk factors by bi-spectral index were sex, operation time, and the American Society of Anaesthesiologists classification. Compared to ETT intubation of <2 h, the risk of MDRPI increased by 7.16 times (95% CI: 1.35–38.00) and 7.93 times (95% CI: 1.45–43.27) for<3 and ≥3 h' duration, respectively. The difficulty of device repositioning can increase the incidence of MDRPI, and prolonged surgery was a significant risk factor. Thus, appropriate planning and correct equipment utilization is needed during prone position spine surgeries. • The most significant risk factor for MDRPIs was operation time. • Among devices, the Wilson frame is associated with the highest risk for MDRPI. • Advanced MDRPIs in the oral mucosa occur earlier than those in the skin. [ABSTRACT FROM AUTHOR]

Structure engineering is essential for manipulating the chemical, electrical, and optical properties of Au. However, it is challenging to design nanoscopic structures because no effective method is available to deviate from the intrinsic evolution behavior during and after synthesis via vapor deposition. Here, we propose an approach that utilizes the oxidation-induced clustering and layering of Au due to the strong O interference at the outmost surfaces of nanoscopic Au geometries. This promotes the evolution of Au clusters and layers that are highly wetted on their oxide supports. A 4-nm-thick epitaxial Au layer eventually evolved from the proposed growth mode, simultaneously exhibiting higher optical transparency than Ag, a near-bulk resistivity of 8 × 10−8 Ω m, and extreme resilience to chemical corrosion and mechanical deformation. This result provides a definite solution to transparent metal electrodes that are highly vulnerable to degradation in ambient and working environments. The study proposes a design rule for manipulating Au clustering dynamics mediated by atomic oxygen surfactants for synthesizing an ultrathin, highly crystalline, 2D-layered Au superstructure providing a breakthrough in research on optoelectrical losses and chemical corrosion in metal electrodes. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Variegated environmental subjectivities emerging from multiple governmentalities. • Local residents conform, contest, and manipulate governmental programmes. • Various, contradictory and surprising positions of environmental subjects. • Situated governmentalities within the experience of the Korean developmental state. This paper explores multiple and variegated environmental subjectivities through the case study of ecotourism development in Jeungdo, South Korea. Drawing on Foucault's work on governmentalities, recent studies on "multiple governmentalities" explore the complex and situated operation of power in contemporary environmental governance. However, limited attention so far has been paid to how multiple governmentalities are experienced by those who are governed. By bringing multiple governmentalities and recent discussions of environmental subjects together, this paper reconfigures environmental subjectivity as multiplicity, from which a variety of subject positions beyond the plan of the governing authorities can emerge. It first examines how local residents of Jeungdo shape their environmental behaviours through multiple governmentalities of ecotourism. It pays particular attention to the ways in which local residents conform, contest, and manipulate governmental programmes, while making references to the site-specific context related to the experience of the developmental state. It then discusses the coexistence and interplay of various, contradictory, and surprising positions of environmental subjects – which I call "multiple environmental subjects" – in relation to the capacity of local residents in the operation of environmental governmentalities. This paper argues that environmental subjectivity is a variegated process in which local residents negotiate governmental programmes in various and creative ways. [ABSTRACT FROM AUTHOR]

Abstract Intensive efforts to engineer the microstructures of materials by utilizing atomic-scale defects have been made to overcome the current limitation on physical properties such as thermoelectric energy conversion performance levels (ZT). Here, we report that (i) internally dispersed strains are generated by a nano-diamond (ND) inserted into polycrystalline Bi-Sb-Te (BST) alloys, which thereby create point-defects clustered zones (PDZs) around the ND/BST interface; (ii) a local strain field is also generated, wherein many point defects are intensified; (iii) locally-strained interfaces result in an increase of the hole carrier concentration caused by the formation of cationic defects. From these results, strain-mediated point defects in ND particle-dispersed BST matrix (ND/BST) composites are assessed as artificial nanostructures, which can independently control transport properties of carriers and phonons. Our findings open new avenues for design and applications of favorable atomic-defect-structures in the area of energy or electronic materials through a classical solid-state sintering method. Graphical abstract fx1 Highlights • Dispersed nanodiamonds generate locally concentrated-strain fields in the matrix. • The locally strained interfaces are corresponding to point-defects clustered zones. • Nanoscale clustering of cationic defects results in hole carrier density. • PDZ independently controls thermal conductivity and power factors for improving ZT. [ABSTRACT FROM AUTHOR]

We previously reported the inhibitory effect of chrysin, a natural flavonoid plentifully contained in propolis, vegetables and fruits, on the mast cell-mediated allergic reaction. In this study, we evaluated the effect of chrysin on atopic dermatitis (AD) and defined underlying mechanisms of action. We used an AD model in BALB/c mice by the repeated local exposure of 2,4-dinitrochlorobenzene (DNCB) and house dust mite ( Dermatophagoides farinae extract, DFE) to the ears. Repeated alternative treatment of DNCB/DFE caused AD-like skin lesions. Oral administration of chrysin diminished AD symptoms such as ear thickness and histopathological analysis, in addition to serum IgE and IgG2a levels. Chrysin decreased infiltration of mast cells, and reduced serum histamine level. Chrysin also suppressed AD by inhibiting the inflammatory responses of Th1, Th2, and Th17 cells in mouse lymph node and ear. Interestingly, chrysin significantly inhibited the production of cytokines, Th2 chemokines, CCL17 and CCL22 by the down-regulation of p38 MAPK, NF-κB, and STAT1 in tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated human keratinocytes (HaCaT). Chrysin also inhibited TNF-α/IFN-γ-stimulated IL-33 expression in HaCaT cells and mouse primary keratinocytes. Taken together, the results indicate that chrysin suppressed AD symptoms, suggesting that chrysin might be a candidate for the treatment of AD and skin allergic diseases. [ABSTRACT FROM AUTHOR]

Highlights: [•] Lithium polymer cells composed of lithium powder anode and LiV3O8 cathode are assembled with cross-linked gel polymer electrolyte. [•] The cells exhibit better capacity retention and greater rate performance than the liquid electrolyte-based cell. [•] The dendritic growth of lithium electrode could be suppressed by the protective gel polymer layer on the lithium powder surface. [ABSTRACT FROM AUTHOR]

Pulmonary nodular lymphoid hyperplasia (PNLH) is a rare, benign lymphoproliferative disease, which is characterized by nonclonal lymphoproliferation. PNLH is usually asymptomatic and usually detected incidentally on imaging studies. Common imaging findings include a solitary nodule, multiple nodules, or focal consolidation. Atypically, PNLH may present with persistent subsolid nodules, mimicking adenocarcinoma. Here, we report a rare case of PNLH presenting as multifocal subsolid nodules in both lower lobes. During follow-up, persistency and growth of the subsolid nodules suggested the possibility of malignancy. Wedge resection was performed bilaterally, and PNLH was confirmed on pathological examination. [ABSTRACT FROM AUTHOR]

Highlights: [&#x2022;] The calbindin expression in the ipsi and contralateral side was found to decrease 6hr after UL. [&#x2022;] Asymmetric calbindin expression was found between ipsi and contralateral nodulus 24hr after UL. [&#x2022;] Forty-eight hours after UL, calbindin expression returned to the control level. [&#x2022;] And asymmetric expression in both noduli also subsided. [ABSTRACT FROM AUTHOR]

Abstract: Ionic liquid-based cross-linked gel polymer electrolytes were prepared with a phosphazene-based cross-linking agent, and their electrochemical properties were investigated. Lithium polymer cells composed of lithium anode and LiCoO2 cathode were assembled with ionic liquid-based cross-linked gel polymer electrolyte and their cycling performance was evaluated. The interfacial adhesion between the electrodes and the electrolyte by in situ chemical cross-linking resulted in stable capacity retention of the cell. A reduction in the ionic mobility in both the electrolyte and the electrode adversely affected discharge capacity and high rate performance of the cell. DSC studies demonstrated that the use of ionic liquid-based cross-linked gel polymer electrolytes provided a significant improvement in the thermal stability of the cell. [Copyright &y& Elsevier]

Abstract: 1-Butyl-1-methylpyrrolidinium hexafluorophosphate (BMP-PF6) was used as a flame-retarding additive in the liquid electrolyte, and the influence of BMP-PF6 content on cycling performance and thermal properties of lithium-ion batteries was investigated. Self-extinguishing time and DSC studies demonstrated that the addition of BMP-PF6 to the electrolyte provided a significant suppression in the flammability of the electrolyte and an improvement in the thermal stability of the cell. The optimum BMP-PF6 content in the electrolyte was found to be 10wt.% for improving safety without degrading cycling performance of the cell. [Copyright &y& Elsevier]

Abstract: A FeSi2.7 thin film is deposited on a copper substrate by RF magnetron sputtering of a Fe–Si alloy target. The electrochemical behavior of the FeSi2.7 electrode in ionic liquid electrolyte based on 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide is investigated and compared with that of a FeSi2.7 electrode in conventional liquid electrolyte. The FeSi2.7 electrode in the ionic liquid electrolyte delivers an initial discharge capacity of 756mAhg−1 at room temperature, and its discharge capacity is maintained to be 92% of the initial discharge capacity after the 100th cycle. AC impedance and FTIR analysis reveal that the formation of a stable solid electrolyte interphase (SEI) layer on the FeSi2.7 electrode in the ionic liquid electrolyte leads to a good capacity retention. This study demonstrates that the FeSi2.7 electrode exhibits stable cycling behavior and good interfacial characteristics in the ionic liquid electrolyte without any solvents and additives. [Copyright &y& Elsevier]

Abstract: Ceramic-coated separators are prepared by coating the sides of a porous polyethylene membrane with nano-sized Al2O3 powder and hydrophilic poly(lithium 4-styrenesulfonate) binder. These separators exhibit an improved thermal stability at high temperatures without significant thermal shrinkage. Due to the high hydrophilicity of the polymer binder and large surface area of the small ceramic particles, the separators show good wettability in non-aqueous liquid electrolytes. By using the ceramic-coated separators, lithium-ion cells composed of a carbon anode and a LiCoO2 cathode are assembled and their cycling performance is evaluated. The cells are proven to have better capacity retention than for cells prepared with polyethylene membrane. It is expected that the ceramic-coated separator in this study can be potential candidate as a separator for rechargeable lithium-ion batteries that require thermal safety and good capacity retention. [Copyright &y& Elsevier]

Abstract: Lithium-ion polymer cells composed of a carbon anode and a LiCoO2 cathode are assembled with a gel polymer electrolyte cured by in-situ chemical cross-linking with novel cross-linking agents. The strong interfacial adhesion between the electrodes and the porous polyethylene membrane by the chemical cross-linking results in the stable capacity retention of the cell. However, a reduction in the ionic mobility in both the electrolyte and the electrodes adversely affects the high rate performance of the cell. These results imply that proper control of the cross-linking density in the cell is imperative for achieving good capacity retention and high rate performance of the cell. [Copyright &y& Elsevier]

Abstract: Endochondral skeletal development begins with the formation of a cartilaginous template where mesenchymal cells aggregate and increase in density prior to their overt differentiation into chondrocytes. Prechondrogenic condensation, in which mesenchymal cells aggregate, requires cell migration and proliferation. However, the molecular mechanisms promoting this aggregation remain to be elucidated. Here, we report that rottlerin suppresses migration and cell surface expression of integrin β1 in chondrogenic progenitors. Perturbation of integrin β1 function using an anti-integrin β1 blocking antibody suppressed the migration of wing bud mesenchymal cells. Furthermore, phosphorylation levels of Src and focal adhesion kinase (FAK) were decreased by rottlerin treatment. Cell treatment with PP2, an inhibitor of Src family kinase, or electroporation of FAK specific siRNA, suppressed cell migration in a wound-healing assay. Cells treated with rottlerin showed decreased phosphorylation of Akt, independent of PKCδ inhibition. In addition, an Akt inhibitor suppressed the migration of chick limb bud mesenchymal cells. Taken together, our results point to the novel finding that rottlerin may act as a negative regulator for cell migration, an essential step for prechondrogenic condensation, by regulating integrin β1 signaling at focal adhesion complexes via modulation of Akt activity. [Copyright &y& Elsevier]

Abstract: We tend to simulate or recall others’ appraisals through auditory verbal imagery (AVI) process to react appropriately. In particular, the ability to imagine derogatory appraisals by others may be critically important for social survival. In this study, we investigated the neural correlates implicated in the processing of unpleasant emotion related to derogatory remark and its self-directedness during AVI process. Twenty-three right-handed healthy human subjects participated in our study. We asked each subject to imagine hearing one’s own or another person’s voice saying derogatory or non-derogatory neutral remarks during the scanning of functional magnetic imaging. A test of the interaction between derogatory emotion and its self-directedness revealed significant activation of the amygdala. Additionally, we observed decreased neural activity in the anterior cingulate cortex (ACC) during imagery of derogatory remarks compared to neutral remarks. Our findings indicate an important role of the amygdala in the processing of unpleasant emotion or self-relevance of information in the real world may also be expanded to the processing of self-directedness of unpleasant emotion in the imagined world, and thereby contribute to human higher social cognitive process. This study also suggests that deactivation of ACC may enable us to enact vivid affective responses, and thereby contribute to an effective simulation of social interaction. [Copyright &y& Elsevier]

Abstract: Acute hypotension induces excitation of electrical activity and expression of c-Fos protein and phosphorylated extracellular signal-regulated kinase (pERK) in the vestibular nuclei. Expression of c-Fos protein and pERK is mediated by the excitatory neurotransmitter, glutamate. In this study, in order to investigate the signaling pathway of glutamate in the vestibular nuclei following acute hypotension, expression of the NR2B subunit of glutamate N-methyl-d-aspartate (NMDA) receptors and the GluR1 subunit of glutamate alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors was measured by Western blotting in the medial vestibular nucleus (MVN) following acute hypotension in bilateral labyrinthectomized (BL) rats. In intact labyrinthine animals, acute hypotension increased expression of pGluR1 and pNR2B in the MVN. Expression of pGluR1 Ser831 and Ser845 peaked at 5 and 30 min after acute hypotension and expression of pNR2B peaked at 60 min after acute hypotension, respectively. In BL animals, expression of pGluR1 Ser831, pGluR1 Ser845, and pNR2B was decreased significantly compared to intact labyrinthine animals following acute hypotension. These results suggest that excitatory afferent signals from the peripheral vestibular receptors, resulting from acute hypotension, release glutamate into postsynaptic neurons in the vestibular nuclei and the excitatory signals are transmitted through the GluR1 subunit of the AMPA receptors and the NR2B subunits of the NMDA receptors in the vestibular system. [Copyright &y& Elsevier]

Abstract: Many burn patients experience psychosocial problems such as personality change, post-traumatic stress disorder, family trouble, and financial burden. The purpose of this study was to identify the risk factors of these psychosocial problems that prevented burn patients from developing appropriate adjustments after burn. Six hundred eighty-six adult burn inpatients were interviewed. Most of them suffered from burns less than 10% of total body surface area. They were asked to fill in a questionnaire for this study, which was a psychosocial problem checklist of 17 items. Descriptive analysis, factor analysis, Chi-square test, and multiple logistic regression analysis were used to analyze the results. Lack of family support and living expense burden were the two significant risk factors for psychosocial problems including, burn treatment problems, rehabilitation problems, and welfare information problems on both acute and chronic burn patients. Medical expense burden was the risk factor among chronic burn patients. These findings suggested that active interventions by the burn team including mental health professionals (psychologist, psychiatrist or social worker) might reduce psychosocial problems of burn patients and encourage social rehabilitation. [Copyright &y& Elsevier]

The expression of phosphorylated extracellular signal-regulated kinase 1/2 (pERK 1/2) was evaluated in the vestibular nuclei (VN) of rats following unilateral labyrinthectomy (UL). Immunohistochemistry revealed a significant asymmetrical increase in pERK 1/2 expression in the VN, 5 min after UL, after which pERK 1/2 immunoreactivity decreased rapidly and was undetectable by 90 min after UL. These results suggest that unilateral deafferentation of the vestibular system triggers intracellular signal pathways that activate ERK 1/2 in the VN. [Copyright &y& Elsevier]