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AimsCalcific aortic valve disease (CAVD) is the most common valve disease, which consists of a chronic interplay of inflammation, fibrosis, and calcification. In this study, sortilin (SORT1) was identified as a novel key player in the pathophysiology of CAVD, and its role in the transformation of valvular interstitial cells (VICs) into pathological phenotypes is explored.Methods and resultsAn aortic valve (AV) wire injury (AVWI) mouse model with sortilin deficiency was used to determine the effects of sortilin on AV stenosis, fibrosis, and calcification. In vitro experiments employed human primary VICs cultured in osteogenic conditions for 7, 14, and 21 days; and processed for imaging, proteomics, and transcriptomics including single-cell RNA-sequencing (scRNA-seq). The AVWI mouse model showed reduced AV fibrosis, calcification, and stenosis in sortilin-deficient mice vs. littermate controls. Protein studies identified the transition of human VICs into a myofibroblast-like phenotype mediated by sortilin. Sortilin loss-of-function decreased in vitro VIC calcification. ScRNA-seq identified 12 differentially expressed cell clusters in human VIC samples, where a novel combined inflammatory myofibroblastic-osteogenic VIC (IMO-VIC) phenotype was detected with increased expression of SORT1, COL1A1, WNT5A, IL-6, and serum amyloid A1. VICs sequenced with sortilin deficiency showed decreased IMO-VIC phenotype.ConclusionSortilin promotes CAVD by mediating valvular fibrosis and calcification, and a newly identified phenotype (IMO-VIC). This is the first study to examine the role of sortilin in valvular calcification and it may render it a therapeutic target to inhibit IMO-VIC emergence by simultaneously reducing inflammation, fibrosis, and calcification, the three key pathological processes underlying CAVD.

Extracellular vesicles (EVs) play a critical role in intercellular communication by transferring microRNAs, lipids, and proteins to neighboring cells. Sortilin, a sorting receptor that directs target proteins to the secretory or endocytic compartments of cells, is found in both EVs and cells. In many human diseases, including cancer and cardiovascular disorders, sortilin expression levels are atypically high. To elucidate the relationship between cardiovascular disease, particularly vascular calcification, and sortilin expression levels, we explored the trafficking of sortilin in both the intracellular and extracellular milieu. We previously demonstrated that sortilin promotes vascular calcification via its trafficking of tissue-nonspecific alkaline phosphatase to EVs. Although recent reports have noted that sortilin is regulated by multiple post-translational modifications, the precise mechanisms of sortilin trafficking still need to be determined. Here, we show that sortilin forms homodimers with an intermolecular disulfide bond at the cysteine 783 (Cys783) residue, and because Cys783 can be palmitoylated, it could be shared via palmitoylation and an intermolecular disulfide bond. Formation of this intermolecular disulfide bond leads to trafficking of sortilin to EVs by preventing palmitoylation, which further promotes sortilin trafficking to the Golgi apparatus. Moreover, we found that sortilin-derived propeptide decreased sortilin homodimers within EVs. In conclusion, sortilin is transported to EVs via the formation of homodimers with an intermolecular disulfide bond, which is endogenously regulated by its own propeptide. Therefore, we propose that inhibiting dimerization of sortilin acts as a new therapeutic strategy for the treatment of EV-associated diseases, including vascular calcification and cancer.

Dynamic metabolic changes occur in the liver during the transition between fasting and feeding. Here we show that transient ER stress responses in the liver following feeding terminated by Sdf2l1 are essential for normal glucose and lipid homeostasis. Sdf2l1 regulates ERAD through interaction with a trafficking protein, TMED10. Suppression of Sdf2l1 expression in the liver results in insulin resistance and increases triglyceride content with sustained ER stress. In obese and diabetic mice, Sdf2l1 is downregulated due to decreased levels of nuclear XBP-1s, whereas restoration of Sdf2l1 expression ameliorates glucose intolerance and fatty liver with decreased ER stress. In diabetic patients, insufficient induction of Sdf2l1 correlates with progression of insulin resistance and steatohepatitis. Therefore, failure to build an ER stress response in the liver may be a causal factor in obesity-related diabetes and nonalcoholic steatohepatitis, for which Sdf2l1 could serve as a therapeutic target and sensitive biomarker., Endoplasmic reticulum (ER) stress has been proposed to play a role in metabolic diseases. Here, Sasako and colleagues identify stromal cell-derived factor 2 like 1 (Sdf2l1) as a regulator of the ER stress response to feeding in the liver, and suggest that its downregulation may promote diabetes and hepatic steatosis in humans.

Objective: Extracellular vesicles (EVs) play a critical role in intercellular communication by transferring microRNAs, lipids and proteins to neighboring cells. Sortilin, a sorting receptor that directs target proteins to the secretary or endocytic compartments of cells, is found in both EVs and cells. In many diseases, including cardiovascular calcification and cancer, sortilin expression levels are atypically high. We previously demonstrated that sortilin promotes vascular calcification via its trafficking of tissue-nonspecific alkaline phosphatase to EVs. Therefore, suppressing trafficking of sortilin to EVs may act as a novel therapy against EV-associated diseases. However, the precise mechanisms of sortilin trafficking remain to be determined. In this study, we hypothesized that dimerization of sortilin regulates its trafficking to EVs. Approach and Results: We found that sortilin forms a homodimer with an intermolecular disulfide bond (IDB) at Cysteine783 (Cys783) residue. Palmitoylation and the IDB formation compete for Cys783. Formation of the IDB led to trafficking of sortilin to EVs by preventing palmitoylation, which further promoted sortilin trafficking to the Golgi apparatus. Moreover, addition of sortilin-derived propeptide decreased sortilin homodimers within EVs, suggesting that the propeptide binding suppresses sortilin trafficking to EVs through prevention of its dimerization. We also found that soluble sortilin secreted by cells overexpressing full-length sortilin forms homodimers with IDBs using various commercially available antibodies against sortilin, thus providing an opportunity for diagnosis of EV-associated diseases by detection of sortilin homodimers in patients. Conclusions: Sortilin is transported to EVs via the formation of homodimers with an IDB, which is endogenously regulated by its own propeptide. Therefore, inhibiting sortilin dimerization may provide a novel therapy against EV-associated diseases, including cardiovascular calcification and cancer. In addition, soluble sortilin homodimer with IDBs could be detected and used as a novel diagnostic biomarker for EV-associated diseases.

application/pdf, Welding in the World. 2015, 59 (4), P.589-595

Background: The rodent salivary gland is not fully developed at birth and the cellular definitive differentiation takes place postnatally. However, little is known about its molecular mechanism. Results: Here we provide the loss-of-function genetic evidence that Runx signaling affects postnatal development of the submandibular gland (SMG). Core binding factor b (Cbfb) is a cotranscription factor which forms a heterodimer with Runx proteins. Cbfb was specifically expressed in the duct epithelium, specifically in the SMG. Epithelial Cbfb deficiency resulted in decrease in the size of the SMG and in the saliva secretion on postnatal day 35. The Cbfb mutant SMG specifically exhibited involution of the granular convoluted tubules (GCT), with a down-regulated expression of its marker genes, such as Klk1, Ngf, and Egf. The induction of GCT is under the control of androgens, and the Cbfb mutant SMG demonstrated down-regulated expression of Crisp3, an androgen-dependent transcript. Because the circulating testosterone or tissue dihydrotestosterone levels were not affected in the Cbfb mutants, it appears that Runx/Cbfb signaling regulate androgen receptor pathway, but does not affect the circulating testosterone levels or the enzymatic conversion to DHT. Conclusions: Runx signaling is important in the postnatal development of androgen-dependent GCT in the SMG. Developmental Dynamics 000:000–000, 2014. V C 2014 Wiley Periodicals, Inc.

In temper bead welding, hardness is one of the key criteria to evaluate the tempering effect. A neural network-based method for hardness prediction in the heat affected zone (HAZ) of low-alloy steel has been investigated in the present study to evaluate the tempering effect in temper bead welding. The new hardness prediction system was constructed by using a neural network based on the experimentally obtained hardness database. On the basis of the thermal cycles numerically obtained by FEM, hardness distribution in HAZ of low alloy steel welded with temper bead welding method was calculated. The predicted hardness was in good accordance with the experimental results. It follows that our new prediction system is effective for estimating the tempering effect in HAZ during temper bead welding and hence enables us to assess the effectiveness of temper bead welding.

A new thermal cycle tempering parameter (TCTP) to characterize the tempering effect during multi-pass thermal cycles has been proposed by extending the Larson-Miller parameter (LMP) to non-isothermal heat treatment. Experimental results revealed that the hardness in synthetic HAZ of low-alloy steel subjected to multi-pass tempering thermal cycles has a good linear relationship with the TCTP. The new hardness prediction system was constructed by using a neural network taking into consideration of the tempering effect during multi-pass welding, estimated by using the TCTP. Based on the thermal cycles numerically obtained by FEM and the experimentally obtained hardness database, the hardness distribution in HAZ of low-alloy steel welded with temper bead welding method was calculated. The predicted hardness was in good accordance with the experimental results. It follows that our new prediction system is effective for estimating the tempering effect in HAZ during multi-pass welding and hence enables us to assess the effectiveness of temper bead welding.

SummaryInsulin receptor substrate (Irs) mediates metabolic actions of insulin. Here, we show that hepatic Irs1 and Irs2 function in a distinct manner in the regulation of glucose homeostasis. The PI3K activity associated with Irs2 began to increase during fasting, reached its peak immediately after refeeding, and decreased rapidly thereafter. By contrast, the PI3K activity associated with Irs1 began to increase a few hours after refeeding and reached its peak thereafter. The data indicate that Irs2 mainly functions during fasting and immediately after refeeding, and Irs1 functions primarily after refeeding. In fact, liver-specific Irs1-knockout mice failed to exhibit insulin resistance during fasting, but showed insulin resistance after refeeding; conversely, liver-specific Irs2-knockout mice displayed insulin resistance during fasting but not after refeeding. We propose the concept of the existence of a dynamic relay between Irs1 and Irs2 in hepatic insulin signaling during fasting and feeding.

We herein describe a novel procedure for dentin regeneration that mimics the biological processes of tooth development in nature. The canonical Wnt signaling pathway is an important regulator of the Dentin sialophosphoprotein (Dspp) expression. Our approach mimics the biological processes underlying tooth development in nature and focuses on the activation of canonical Wnt signaling to trigger the natural process of dentinogenesis. The coronal portion of the dentin and the underlying pulp was removed from the first molars. We applied lithium chloride (LiCl), an activator of canonical Wnt signaling, on the amputated pulp surface to achieve transdifferentiation toward odontoblasts from the surrounding pulpal cells. MicroCT and microscopic analyses demonstrated that the topical application of LiCl induced dentin repair, including the formation of a complete dentin bridge. LiCl-induced dentin is a tubular dentin in which the pulp cells are not embedded within the matrix, as in primary dentin. In contrast, a dentin bridge was not induced in the control group treated with pulp capping with material carriers alone, although osteodentin without tubular formation was induced at a comparatively deeper position from the pulp exposure site. We also evaluated the influence of LiCl on differentiation toward odontoblasts in vitro. In the mDP odontoblast cell line, LiCl activated the mRNA expression of Dspp, Axin2 and Kallikrein 4 (Klk4) and downregulated the Osteopontin (Osp) expression. These results provide a scientific basis for the biomimetic regeneration of dentin using LiCl as a new capping material to activate dentine regeneration.

Nectins are Ca2+-independent immunoglobulin-like cell-cell adhesion molecules that play roles in organization of a variety of cell-cell junctions in cooperation with or independently of cadherins. Four nectins have been identified. Five nectin-like molecules, which have domain structures similar to those of nectins, have been identified, and we characterized here nectin-like molecule-2 (Necl-2)/IGSF4/RA175/SgIGSF/TSLC1/SynCAM1. Necl-2 showed Ca2+-independent homophilic cell-cell adhesion activity. It furthermore showed Ca2+-independent heterophilic cell-cell adhesion activity with Necl-1/TSLL1/SynCAM3 and nectin-3. Necl-2 was widely expressed in rat tissues examined. Necl-2 localized at the basolateral plasma membrane in epithelial cells of the mouse gall bladder, but not at specialized cell-cell junctions, such as tight junctions, adherens junctions, and desmosomes. Nectins bind afadin, whereas Necl-2 did not bind afadin but bound Pals2, a membrane-associated guanylate kinase family member known to bind Lin-7, implicated in the proper localization of the Let-23 protein in Caenorhabditis elegans, the homologue of mammalian epidermal growth factor receptor. These results indicate the unique localization of Necl-2 and its possible involvement in localization of a transmembrane protein(s) through Pals2.

Malignant transformation of cells causes disruption of cell-cell adhesion, enhancement of cell motility, and invasion into surrounding tissues. Nectins have both homophilic and heterophilic cell-cell adhesion activities and organize adherens junctions in cooperation with cadherins. We examined here whether Tage4, which was originally identified to be a gene overexpressed in colon carcinoma and has a domain structure similar to those of nectins, is involved in cell adhesion and/or migration. Tage4 heterophilically trans-interacted with nectin-3, but not homophilically with Tage4. Expression of Tage4 was markedly elevated in NIH3T3 cells transformed by an oncogenic Ki-Ras (V12Ras-NIH3T3 cells) as compared with that of wild-type NIH3T3 cells. trans-Interaction of Tage4 with nectin-3 enhanced motility of V12Ras-NIH3T3 cells. Tage4 did not bind afadin, a nectin- and actin filament-binding protein that connects nectins to the actin cytoskeleton and cadherins through catenins. Thus, Tage4 heterophilically trans-interacts with nectin-3 and regulates cell migration. Tage4 is tentatively re-named here nectin-like molecule-5 (necl-5) on the basis of its function and domain structure similar to those of nectins.

In this study, a spectroscopic method is applied to measure two-dimensional (2D) distributions of flame temperatures during regenerative combustion of natural gas with highly preheated air in a test furnace of industrial size. By using a CCD camera fitted with an optical bandpass filter, the 2D distributions of the continuum emission from soot particles in premix and diffusion flames are measured at two different wavelengths. Subsequently, the temperature is determined on the basis of the two-color 2D thermometry, in which the ratio of the 2D emission intensity distributions is converted into the 2D temperature distribution with much higher spatial resolution in comparison with those obtainable by thermocouples. The emission profiles of NO radiation also were measured and the results are discussed in conjunction with difference in the temperature profiles of the flames.

To prevent primary water stress corrosion cracking (PWSCC), water jet peening (WJP) has been used on the welds of Ni-based alloys in pressurized water reactors (PWRs). Before WJP, the welds are machined and buffed in order to conduct a penetrant test (PT) to verify the weld qualities to access, and microstructure evolution takes place in the target area due to the severe plastic deformation. The compressive residual stresses induced by WJP might be unstable under elevated temperatures because of the high dislocation density in the compressive stress layer. Therefore, the stability of the compressive residual stresses caused by WJP was investigated during long-term operation by considering the microstructure evolution due to the working processes. The following conclusions were made: The compressive residual stresses were slightly relaxed in the surface layers of the thermally aged specimens. There were no differences in the magnitude of the relaxation based on temperature or time. The compressive residual stresses induced by WJP were confirmed to remain stable under elevated temperatures. The stress relaxation at the surface followed the Johnson–Mehl equation, which states that stress relaxation can occur due to the recovery of severe plastic strain, since the estimated activation energy agrees very well with the self-diffusion energy for Ni. By utilizing the additivity rule, it was indicated that stress relaxation due to recovery is completed during the startup process. It was proposed that the long-term stability of WJP under elevated temperatures must be assessed based on compressive stresses with respect to the yield stress. Thermal elastic–plastic creep analysis was performed to predict the effect of creep strain. After 100 yr of simulated continuous operation at 80% capacity, there was little change in the WJP compressive stresses under an actual operating temperature of 623 K. Therefore, the long-term stability of WJP during actual operation was analytically predicted.

Previously we showed that CCN family member 2/connective tissue growth factor (CCN2) promotes the proliferation, differentiation, and maturation of growth cartilage cells in vitro. To elucidate the specific role and molecular mechanism of CCN2 in cartilage development in vivo, in the present study we generated transgenic mice overexpressing CCN2 and analyzed them with respect to cartilage and bone development. Transgenic mice were generated expressing a ccn2/lacZ fusion gene in cartilage under the control of the 6 kb-Col2a1-enhancer/promoter. Changes in cartilage and bone development were analyzed histologically and immunohistologically and also by micro CT. Primary chondrocytes as well as limb bud mesenchymal cells were cultured and analyzed for changes in expression of cartilage-related genes, and non-transgenic chondrocytes were treated in culture with recombinant CCN2. Newborn transgenic mice showed extended length of their long bones, increased content of proteoglycans and collagen II accumulation. Micro-CT analysis of transgenic bones indicated increases in bone thickness and mineral density. Chondrocyte proliferation was enhanced in the transgenic cartilage. In in vitro short-term cultures of transgenic chondrocytes, the expression of col2a1, aggrecan and ccn2 genes was substantially enhanced; and in long-term cultures the expression levels of these genes were further enhanced. Also, in vitro chondrogenesis was strongly enhanced. IGF-I and IGF-II mRNA levels were elevated in transgenic chondrocytes, and treatment of non-transgenic chondrocytes with recombinant CCN2 stimulated the expression of these mRNA. The addition of CCN2 to non-transgenic chondrocytes induced the phosphorylation of IGFR, and ccn2-overexpressing chondrocytes showed enhanced phosphorylation of IGFR. Our data indicates that the observed effects of CCN2 may be mediated in part by CCN2-induced overexpression of IGF-I and IGF-II. These findings indicate that CCN2-overexpression in transgenic mice accelerated the endochondral ossification processes, resulting in increased length of their long bones. Our results also indicate the possible involvement of locally enhanced IGF-I or IGF-II in this extended bone growth.

BACKGROUND:K-134 is a more potent antiplatelet drug with a selective inhibitory effect on phosphodiesterase 3 (PDE3) compared with its analogue, cilostazol. OBJECTIVES:This study was performed to compare the ameliorating effects of K-134 and cilostazol on brain damage in an experimental photothrombotic cerebral infarction model. METHODS AND RESULTS:We investigated the effects of oral preadministration of PDE3 inhibitors in a rat stroke model established by photothrombotic middle cerebral artery (MCA) occlusion. K-134 significantly prolonged MCA occlusion time at doses >10 mg/kg, and reduced cerebral infarct size at 30 mg/kg in the stroke model (n = 12, 87.5±5.6 vs. 126.8±7.5 mm(3), P

Adiponectin has been proposed to act as an antidiabetic adipokine, suppressing gluconeogenesis and stimulating fatty acid oxidation in the liver and skeletal muscle. Although adiponectin-knockout (adipo(-/-)) mice are known to exhibit insulin resistance, the degrees of insulin resistance and glucose intolerance are unexpectedly only moderate. In this study, the adipo(-/-) mice showed hepatic, but not muscle, insulin resistance. insulin-stimulated phosphorylation of IRS-1 and IRS-2 was impaired, the IRS-2 protein level was decreased, and insulin-stimulated phosphorylation of Akt was decreased in the liver of the adipo(-/-) mice. However, the triglyceride content in the liver was not increased in these mice, despite the decrease in the PPARalpha expression involved in lipid combustion, since the expressions of lipogenic genes such as SREBP-1 and SCD-1 were decreased in association with the increased leptin sensitivity. Consistent with this, the down-regulation SREBP-1 and SCD-1 observed in the adipo(-/-) mice was no longer observed, and the hepatic triglyceride content was significantly increased in the adiponectin leptin double-knockout (adipo(-/-)ob/ob) mice. On the other hand, the triglyceride content in the skeletal muscle was significantly decreased in the adipo(-/-) mice, probably due to up-regulated AMPK activity associated with the increased leptin sensitivity. In fact, these phenotypes in the skeletal muscle of these mice were no longer observed in the adipo(-/-)ob/ob mice. In conclusion, adipo(-/-) mice showed impaired insulin signaling in the liver to cause hepatic insulin resistance, however, no increase in the triglyceride content was observed in either the liver or the skeletal muscle, presumably on account of the increased leptin sensitivity.

Thiazolidinediones have been shown to up-regulate adiponectin expression in white adipose tissue and plasma adiponectin levels, and these up-regulations have been proposed to be a major mechanism of the thiazolidinedione-induced amelioration of insulin resistance linked to obesity. To test this hypothesis, we generated adiponectin knock-out (adipo-/-) ob/ob mice with a C57B/6 background. After 14 days of 10 mg/kg pioglitazone, the insulin resistance and diabetes of ob/ob mice were significantly improved in association with significant up-regulation of serum adiponectin levels. Amelioration of insulin resistance in ob/ob mice was attributed to decreased glucose production and increased AMP-activated protein kinase in the liver but not to increased glucose uptake in skeletal muscle. In contrast, insulin resistance and diabetes were not improved in adipo-/-ob/ob mice. After 14 days of 30 mg/kg pioglitazone, insulin resistance and diabetes of ob/ob mice were again significantly ameliorated, which was attributed not only to decreased glucose production in the liver but also to increased glucose uptake in skeletal muscle. Interestingly, adipo-/-ob/ob mice also displayed significant amelioration of insulin resistance and diabetes, which was attributed to increased glucose uptake in skeletal muscle but not to decreased glucose production in the liver. The serum-free fatty acid and triglyceride levels as well as adipocyte sizes in ob/ob and adipo-/-ob/ob mice were unchanged after 10 mg/kg pioglitazone but were significantly reduced to a similar degree after 30 mg/kg pioglitazone. Moreover, the expressions of TNFalpha and resistin in adipose tissues of ob/ob and adipo-/-ob/ob mice were unchanged after 10 mg/kg pioglitazone but were decreased after 30 mg/kg pioglitazone. Thus, pioglitazone-induced amelioration of insulin resistance and diabetes may occur adiponectin dependently in the liver and adiponectin independently in skeletal muscle.

Nectins are Ca2+-independent immunoglobulin-like cell-cell adhesion molecules and comprise a family of four members. At the mossy fiber terminals of hippocampus, nectin-1 and nectin-3 localize at the presynaptic and postsynaptic sides of synaptic junctions, respectively, and their trans-interactions play a role in formation of synapses in cooperation with N-cadherin. Nectins are associated with the actin cytoskeleton through afadin, a nectin- and actin-filament-binding protein. Five nectin-like molecules (Necls) which have domain structures similar to those of nectins have been identified and here we characterize Necl-1/TSLL1/SynCAM3, from now on referred to as Necl-1. Tissue distribution analysis showed that Necl-1 was specifically expressed in the neural tissue. Immunofluorescence and immunoelectron microscopy revealed that Necl-1 localized at the contact sites among axons, their terminals, and glia cell processes that cooperatively formed synapses, axon bundles and myelinated axons. Necl-1 showed Ca2+-independent homophilic cell-cell adhesion activity. It furthermore showed Ca2+-independent heterophilic cell-cell adhesion activity with Necl-2/IGSF4/RA175/SgIGSF/TSLC1/SynCAM1 from now on referred to as Necl-2, nectin-1 and nectin-3, but not with Necl-5 or nectin-2. The C-terminal cytoplasmic region of Necl-1 did not bind afadin but bound membrane-associated guanylate kinase subfamily members that contain the L27 domain, including Dlg3, Pals2 and CASK. These results indicate that Necl-1 is a neural-tissue-specific Ca2+-independent immunoglobulin-like cell-cell adhesion molecule which potentially has membrane-associated guanylate kinase subfamily member-binding activity and localizes at the non-junctional cell-cell contact sites.

Frabin is an actin filament (F-actin)-binding protein with GDP/GTP exchange activity specific for Cdc42 small G protein. Expression of frabin forms filopodia-like microspikes through the direct activation of Cdc42, and lamellipodia through indirect activation of Rac small G protein. Frabin consists of the F-actin-binding domain (FAB), the Dbl homology domain (DH), the first pleckstrin homology domain (PH1), the FYVE-finger domain (FYVE), the second PH domain (PH2) from the N-terminus in this order. Although DH and PH1 show exchange activity, FAB, in addition to DH and PH1, is required for the formation of microspikes, whereas FYVE and PH2, in addition to DH and PH1, are required for the formation of lamellipodia.Various truncated mutants of frabin were co-expressed with a dominant active mutant (DA) of Cdc42, Rac1DA, or full-length frabin in L fibroblasts. FAB was recruited to the Cdc42DA-formed filopodia-like microspikes. FAB and a fragment containing DH, PH1, FYVE and PH2 were recruited to the Rac1DA-formed membrane ruffles. Furthermore, each of these fragments served as a dominant negative mutant of frabin when co-expressed with full-length frabin, and inhibited the full-length frabin-formed morphological changes.These results suggest that frabin recognizes a specific actin structure(s) through FAB and a specific membrane structure(s) through FAB and the region containing DH, PH1, FYVE and PH2. It is likely that frabin associates with the specific actin and membrane structures and activates Cdc42 and Rac in the vicinity of these structures, eventually leading to morphological changes.

It is impossible to avoid welding deformations when steel structures such as ships are assembled. Therefore, quantitative prediction and effective control of residual welding deformation are necessary. However, the current finite element analysis requires very long computational time and memory. To solve this problem, we have developed an inherent strain analysis method using idealized explicit FEM and have applied this proposed method to a ship block model. The simulated results agree well with the measured deformation. Furthermore, the influence of various factors on the welding deformation of targeted ship block is also investigated.

Highly precise fabrication of welded materials is in great demand, and so microstructure and distortion controls are essential. Furthermore, consideration of process mechanics is important for intelligent fabrication. In this study, the microstructure and hardness distribution in multi-pass weld metal are evaluated by computational simulations under the conditions of multiple heat cycles and phase transformation. Because conventional CCT diagrams of weld metal are not available even for single-pass weld metal, new diagrams for multi-pass weld metals are created. The weld microstructure and hardness distribution are precisely predicted when using the created CCT diagram for multi-pass weld metal and calculating the weld thermal cycle. Weld distortion is also investigated by using numerical simulation with a thermal elastic-plastic analysis. In conventional evaluations of weld distortion, the average heat input has been used as the dominant parameter; however, it is difficult to consider the effect of molten pool configurations on weld distortion based only on the heat input. Thus, the effect of welding process conditions on weld distortion is studied by considering molten pool configurations, determined by temperature distribution and history.

SummaryIn obese patients with type 2 diabetes, insulin delivery to and insulin-dependent glucose uptake by skeletal muscle are delayed and impaired. The mechanisms underlying the delay and impairment are unclear. We demonstrate that impaired insulin signaling in endothelial cells, due to reduced Irs2 expression and insulin-induced eNOS phosphorylation, causes attenuation of insulin-induced capillary recruitment and insulin delivery, which in turn reduces glucose uptake by skeletal muscle. Moreover, restoration of insulin-induced eNOS phosphorylation in endothelial cells completely reverses the reduction in capillary recruitment and insulin delivery in tissue-specific knockout mice lacking Irs2 in endothelial cells and fed a high-fat diet. As a result, glucose uptake by skeletal muscle is restored in these mice. Taken together, our results show that insulin signaling in endothelial cells plays a pivotal role in the regulation of glucose uptake by skeletal muscle. Furthermore, improving endothelial insulin signaling may serve as a therapeutic strategy for ameliorating skeletal muscle insulin resistance.