Extracellular calcium increases fibroblast growth factor 2 gene expression via extracellular signal-regulated kinase 1/2 and protein kinase A signaling in mouse dental papilla cells

We previously reported that elevated extracellular calcium (Ca2+) levels increase bone morphogenetic protein 2 expression in human dental pulp (hDP) cells. However, it is unknown whether extracellular Ca2+ affects the expression of other growth factors such as fibroblast growth factor 2 (FGF2). Objective: The present study aimed to examine the effect of extracellular Ca2+ on FGF2 gene expression in hDP and immortalized mouse dental papilla (mDP) cells. Materials and Methods: Cells were stimulated with 10 mM CaCl2 in the presence or absence of cell signaling inhibitors. FGF2 gene expression was assessed using real-time polymerase chain reaction. The phosphorylation status of signaling molecules was examined by Western blotting. Results: Extracellular Ca2+ increased FGF2 gene expression in mDP and hDP cells. Gene expression of the calcium-sensing receptor and G protein-coupled receptor family C group 6 member A, both of which are extracellular Ca2+ sensors, was not detected. Ca2+-mediated Fgf2 expression was reduced by pretreatment with the protein kinase A (PKA) inhibitor H-89 or extracellular signal-regulated kinase (ERK) 1/2 inhibitor PD98059 but not by pretreatment with the protein kinase C inhibitor GF-109203X or p38 inhibitor SB203580. Extracellular Ca2+ increased PKA activity and ERK1/2 phosphorylation. Ca2+-induced PKA activity decreased by pretreatment with PD98059. Conclusions: These findings indicate that elevated extracellular Ca2+ levels led to increased Fgf2 expression through ERK1/2 and PKA in mDP cells and that this mechanism may be useful for designing regenerative therapies for dentin

Cyclic Stretch Negatively Regulates IL-1β Secretion Through the Inhibition of NLRP3 Inflammasome Activation by Attenuating the AMP Kinase Pathway

Macrophages are immune cells of hematopoietic origin that play diverse roles in host defenses and tissue homeostasis. In mechanical microenvironments, macrophages receive mechanical signals that regulate various cellular functions. However, the mechanisms by which mechanical signals influence the phenotype and function of macrophages in the process of inflammation have not yet been elucidated in detail. We herein examined the effects of cyclic stretch (CS) on NLR family, pyrin domain-containing 3 (NLRP3) inflammasome activation in J774.1, a murine macrophage cell line, and mouse primary bone marrow-derived macrophages. We showed that cyclic stretch inhibited adenosine triphosphate (ATP)-stimulated interleukin (IL)-1β secretion in lipopolysaccharide (LPS)-primed macrophages using ELISA and Western blot analyses. Cyclic stretch did not affect the degradation of the Inhibitor of κB or the nuclear translocation/transcriptional activity of nuclear factor (NF)-κB, suggesting that cyclic stretch-mediated inhibition was independent of the NF-κB signaling pathway. Consistent with these results, cyclic stretch did not affect the LPS-induced expression of inflammasome components, such as pro-IL-1β and NLRP3, which is known to require the activation of NF-κB signaling. We showed that the cyclic stretch-mediated inhibition of IL-1β secretion was caused by the suppression of caspase-1 activity. The addition of compound C, a specific inhibitor of adenosine monophosphate-activated protein kinase (AMPK), to LPS-primed macrophages inhibited IL-1β secretion as well as caspase-1 activation, suggesting that AMPK signaling is involved in ATP-triggered IL-1β secretion. Furthermore, the phosphorylation of AMPK induced by ATP in LPS-primed macrophages was significantly suppressed by cyclic stretch, indicating that cyclic stretch negatively regulates IL-1β secretion through the inhibition of caspase-1 activity by attenuating the AMPK pathway. Our results suggest that mechanical stress functions to maintain homeostasis through the prevention of excessive inflammasome activation in macrophages in mechanical microenvironments

Orbital characterization of GJ1108A system, and comparison of dynamical mass with model-derived mass for resolved binaries

We report an orbital characterization of GJ1108Aab that is a low-mass binary system in pre-main-sequence phase. Via the combination of astrometry using adaptive optics and radial velocity measurements, an eccentric orbital solution of $e$=0.63 is obtained, which might be induced by the Kozai-Lidov mechanism with a widely separated GJ1108B system. Combined with several observed properties, we confirm the system is indeed young. Columba is the most probable moving group, to which the GJ1108A system belongs, although its membership to the group has not been established. If the age of Columba is assumed for GJ1108A, the dynamical masses of both GJ1108Aa and GJ1108Ab ($M_{\rm dynamical,GJ1108Aa}=0.72\pm0.04 M_{\odot}$ and $M_{\rm dynamical,GJ1108Ab}=0.30\pm0.03 M_{\odot}$) are more massive than what an evolutionary model predicts based on the age and luminosities. We consider the discrepancy in mass comparison can attribute to an age uncertainty; the system is likely older than stars in Columba, and effects that are not implemented in classical models such as accretion history and magnetic activity are not preferred to explain the mass discrepancy. We also discuss the performance of the evolutionary model by compiling similar low-mass objects in evolutionary state based on the literature. Consequently, it is suggested that the current model on average reproduces the mass of resolved low-mass binaries without any significant offsets.Comment: Accepted in Ap

Lightweight rigidly foldable canopy using composite materials

This paper presents a novel origami-based portable deployable canopy system developed using fiber reinforced plastics. A modular system composed of multiple developable strips is proposed to provide a one degree-of-freedom deployment motion from a flat-folded state to a fully deployed state. Each strip is comprised of panels with embedded compliant hinges whose pattern is created in a planar configuration through the laying out of prepreg composite sheets and multi-step curing. The design process of a canopy using this system is demonstrated herein. To capture the complex behaviors and functionality, the design process involves developing different analytical models for each step starting with a simplified model and ending with a refined model. In this case, we defined a parametric design family from rigid origami theory and determined preliminary design parameters through a multi-objective optimization (MOO) scheme in order to balance performance against manufacturing constraints. We then applied geometric nonlinear analyses to assess the kinematic behaviors of the folding actions and also the buckling behavior of the structure in its deployed state. The analyses indicated the need for stability improvement, provided using tension elements. The structure was divided into developable parts that can be manufactured in a planar state. With a total mass of 27 kg, the system can be carried by two or three persons and deployed within a minute

Extracellular calcium increases fibroblast growth factor 2 gene expression via extracellular signal-regulated kinase 1/2 and protein kinase A signaling in mouse dental papilla cells

<div><p>Abstract We previously reported that elevated extracellular calcium (Ca2+) levels increase bone morphogenetic protein 2 expression in human dental pulp (hDP) cells. However, it is unknown whether extracellular Ca2+ affects the expression of other growth factors such as fibroblast growth factor 2 (FGF2). Objective: The present study aimed to examine the effect of extracellular Ca2+ on FGF2 gene expression in hDP and immortalized mouse dental papilla (mDP) cells. Materials and Methods: Cells were stimulated with 10 mM CaCl2 in the presence or absence of cell signaling inhibitors. FGF2 gene expression was assessed using real-time polymerase chain reaction. The phosphorylation status of signaling molecules was examined by Western blotting. Results: Extracellular Ca2+ increased FGF2 gene expression in mDP and hDP cells. Gene expression of the calcium-sensing receptor and G protein-coupled receptor family C group 6 member A, both of which are extracellular Ca2+ sensors, was not detected. Ca2+-mediated Fgf2 expression was reduced by pretreatment with the protein kinase A (PKA) inhibitor H-89 or extracellular signal-regulated kinase (ERK) 1/2 inhibitor PD98059 but not by pretreatment with the protein kinase C inhibitor GF-109203X or p38 inhibitor SB203580. Extracellular Ca2+ increased PKA activity and ERK1/2 phosphorylation. Ca2+-induced PKA activity decreased by pretreatment with PD98059. Conclusions: These findings indicate that elevated extracellular Ca2+ levels led to increased Fgf2 expression through ERK1/2 and PKA in mDP cells and that this mechanism may be useful for designing regenerative therapies for dentin.</p></div

Image_2_Cyclic Stretch Negatively Regulates IL-1β Secretion Through the Inhibition of NLRP3 Inflammasome Activation by Attenuating the AMP Kinase Pathway.TIF

<p>Macrophages are immune cells of hematopoietic origin that play diverse roles in host defenses and tissue homeostasis. In mechanical microenvironments, macrophages receive mechanical signals that regulate various cellular functions. However, the mechanisms by which mechanical signals influence the phenotype and function of macrophages in the process of inflammation have not yet been elucidated in detail. We herein examined the effects of cyclic stretch (CS) on NLR family, pyrin domain-containing 3 (NLRP3) inflammasome activation in J774.1, a murine macrophage cell line, and mouse primary bone marrow-derived macrophages. We showed that cyclic stretch inhibited adenosine triphosphate (ATP)-stimulated interleukin (IL)-1β secretion in lipopolysaccharide (LPS)-primed macrophages using ELISA and Western blot analyses. Cyclic stretch did not affect the degradation of the Inhibitor of κB or the nuclear translocation/transcriptional activity of nuclear factor (NF)-κB, suggesting that cyclic stretch-mediated inhibition was independent of the NF-κB signaling pathway. Consistent with these results, cyclic stretch did not affect the LPS-induced expression of inflammasome components, such as pro-IL-1β and NLRP3, which is known to require the activation of NF-κB signaling. We showed that the cyclic stretch-mediated inhibition of IL-1β secretion was caused by the suppression of caspase-1 activity. The addition of compound C, a specific inhibitor of adenosine monophosphate-activated protein kinase (AMPK), to LPS-primed macrophages inhibited IL-1β secretion as well as caspase-1 activation, suggesting that AMPK signaling is involved in ATP-triggered IL-1β secretion. Furthermore, the phosphorylation of AMPK induced by ATP in LPS-primed macrophages was significantly suppressed by cyclic stretch, indicating that cyclic stretch negatively regulates IL-1β secretion through the inhibition of caspase-1 activity by attenuating the AMPK pathway. Our results suggest that mechanical stress functions to maintain homeostasis through the prevention of excessive inflammasome activation in macrophages in mechanical microenvironments.</p

Image_1_Cyclic Stretch Negatively Regulates IL-1β Secretion Through the Inhibition of NLRP3 Inflammasome Activation by Attenuating the AMP Kinase Pathway.TIF

<p>Macrophages are immune cells of hematopoietic origin that play diverse roles in host defenses and tissue homeostasis. In mechanical microenvironments, macrophages receive mechanical signals that regulate various cellular functions. However, the mechanisms by which mechanical signals influence the phenotype and function of macrophages in the process of inflammation have not yet been elucidated in detail. We herein examined the effects of cyclic stretch (CS) on NLR family, pyrin domain-containing 3 (NLRP3) inflammasome activation in J774.1, a murine macrophage cell line, and mouse primary bone marrow-derived macrophages. We showed that cyclic stretch inhibited adenosine triphosphate (ATP)-stimulated interleukin (IL)-1β secretion in lipopolysaccharide (LPS)-primed macrophages using ELISA and Western blot analyses. Cyclic stretch did not affect the degradation of the Inhibitor of κB or the nuclear translocation/transcriptional activity of nuclear factor (NF)-κB, suggesting that cyclic stretch-mediated inhibition was independent of the NF-κB signaling pathway. Consistent with these results, cyclic stretch did not affect the LPS-induced expression of inflammasome components, such as pro-IL-1β and NLRP3, which is known to require the activation of NF-κB signaling. We showed that the cyclic stretch-mediated inhibition of IL-1β secretion was caused by the suppression of caspase-1 activity. The addition of compound C, a specific inhibitor of adenosine monophosphate-activated protein kinase (AMPK), to LPS-primed macrophages inhibited IL-1β secretion as well as caspase-1 activation, suggesting that AMPK signaling is involved in ATP-triggered IL-1β secretion. Furthermore, the phosphorylation of AMPK induced by ATP in LPS-primed macrophages was significantly suppressed by cyclic stretch, indicating that cyclic stretch negatively regulates IL-1β secretion through the inhibition of caspase-1 activity by attenuating the AMPK pathway. Our results suggest that mechanical stress functions to maintain homeostasis through the prevention of excessive inflammasome activation in macrophages in mechanical microenvironments.</p

Comparing the Efficacy of a Microperforated Titanium Membrane for Guided Bone Regeneration with an Existing Mesh Retainer in Dog Mandibles

Acute-type lateral ridge defects (25 mm × 6 mm × 5 mm) were bilaterally created in the mandibles of four dogs (two defects per animal). The defects were reconstructed with particulate autologous bone and covered with a microperforated titanium membrane (Ti-honeycomb membrane, TiHM) or an existing conventional titanium mesh as control. The samples were dissected after 16 weeks postoperatively and processed for radiographic, histologic, and histomorphometric analyses. Regenerated tissue and bone volume were significantly larger in the TiHM group than in the control group (p = 0.05; p = 0.049). In contrast, bone mineral density was similar between the two groups. Histomorphometric analysis revealed that the regenerated bone area and calcific osseous area were larger in the TiHM group than in the control group; however, the differences were not significant. The efficacy of TiHM was generally satisfactory with the potential to become a standard tool for the GBR procedure; however, early membrane exposure will be a major problem to overcome

Genomic Anatomy of a Premier Major Histocompatibility Complex Paralogous Region on Chromosome 1q21–q22

Human chromosomes 1q21–q25, 6p21.3–22.2, 9q33–q34, and 19p13.1–p13.4 carry clusters of paralogous loci, to date best defined by the flagship 6p MHC region. They have presumably been created by two rounds of large-scale genomic duplications around the time of vertebrate emergence. Phylogenetically, the 1q21–25 region seems most closely related to the 6p21.3 MHC region, as it is only the MHC paralogous region that includes bona fide MHC class I genes, the CD1 and MR1 loci. Here, to clarify the genomic structure of this model MHC paralogous region as well as to gain insight into the evolutionary dynamics of the entire quadriplication process, a detailed analysis of a critical 1.7 megabase (Mb) region was performed. To this end, a composite, deep, YAC, BAC, and PAC contig encompassing all five CD1 genes and linking the centromeric +P5 locus to the telomeric KRTC7 locus was constructed. Within this contig a 1.1-Mb BAC and PAC core segment joining CD1D to FCER1A was fully sequenced and thoroughly analyzed. This led to the mapping of a total of 41 genes (12 expressed genes, 12 possibly expressed genes, and 17 pseudogenes), among which 31 were novel. The latter include 20 olfactory receptor (OR) genes, 9 of which are potentially expressed. Importantly, CD1, SPTA1, OR, and FCERIA belong to multigene families, which have paralogues in the other three regions. Furthermore, it is noteworthy that 12 of the 13 expressed genes in the 1q21–q22 region around the CD1 loci are immunologically relevant. In addition to CD1A-E, these include SPTA1, MNDA, IFI-16, AIM2, BL1A, FY and FCERIA. This functional convergence of structurally unrelated genes is reminiscent of the 6p MHC region, and perhaps represents the emergence of yet another antigen presentation gene cluster, in this case dedicated to lipid/glycolipid antigens rather than antigen-derived peptides. [The nucleotide sequence data reported in this paper have been submitted to the DDBJ, EMBL, and GenBank databases under accession nos. AB045357–AB045365.