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High-mobility group box-1 (HMGB1) protein acts as a transcription factor in the nucleus and also as a pro-inflammatory cytokine when released into extracellular fluids. The presence of higher levels of HMGB1 is reported in the gingival crevicular fluid from periodontal patients. Since the proliferation of bacteria within the periodontal pocket is closely involved in the exacerbation of periodontal disease, it is hypothesized that the periodontal pocket causes the release of HMGB1. Immunohistochemical staining of inflamed gingiva revealed that HMGB1 is exclusively dislocated from the nucleus to the cytoplasm in the pocket epithelium, whereas it is mainly present in the nucleus in the gingival epithelium. Butyric acid, an extracellular metabolite from periodontopathic bacteria populating the periodontal pocket, induced the passive release of HMGB1 as a result of eliciting necrosis in the human gingival epithelial cell line. Thus, the periodontal epithelium may provide a unique pathological setting for HMGB1 release by bacterial insult. Abbreviations: HMGB1, high-mobility group box-1; TNF-α, tumor necrosis factor-α; CHX, cycloheximide; PI, propidium iodide; ROS, reactive oxygen species; HDAC, histone deacetylase. [ABSTRACT FROM PUBLISHER]

Objective: By maximizing the advantages of exoscopy, we developed a keyhole approach for intracranial hematoma removal. Herein, we validated the utility of this procedure, and compared it with conventional microscopic hematoma removal and endoscopic hematoma removal in our institution., Methods: We included 12 consecutive patients who underwent this procedure from June 2022 to March 2024. A 4-cm-long skin incision was made, and a keyhole craniotomy (diameter, 2.5 cm) was performed. An assistant manipulated a spatula, and an operator performed hematoma removal and hemostasis using typical microsurgical techniques under an exoscope. The dura mater was reconstructed without sutures using collagen matrix and fibrin glue. The outcomes of this series were compared with those of 12 consecutive endoscopic hematoma removals and 19 consecutive conventional microscopic hematoma removals from October 2018 to March 2024., Results: The mean age was 72±10 years, and 7 (58%) patients were men. Hematoma location was the putamen in 5 patients and subcortical in 7 patients. The mean operative time was 122±34 min, the mean hematoma removal rate was 95%±8%, and the mortality rate was 0%. Although the preoperative hematoma volume was similar between the 3 groups, the operative time and total time in the operating room was significantly shorter in the exoscope group than in the microscope group (P<0.0001)., Conclusions: This procedure may be simpler and faster than conventional microscopic hematoma removal, and comparable to endoscopic hematoma removal., (Copyright © 2024 Elsevier Inc. All rights reserved.)

A liquid piston Stirling engine is an external combustion engine that uses air and water under atmospheric pressure as its working fluids. Resulting from its uncomplicated design and the capacity to operate under relatively low temperature differentials of less than 100 °C, it has attracted considerable attention in recent years. This paper presents the fundamental characteristics of the liquid piston engine combined with a self-rectifying turbine for the advancement of thermal generators. When the turbine is installed in the water region rather than in the air region, it exhibits unidirectional rotation with a rotational speed directly proportional to the velocity amplitude of the reciprocating axial flow. Additionally, the acoustic impedance within the duct section containing the turbine is determined, demonstrating that the real part of impedance rises with increasing axial velocity, indicating a loss mechanism similar to the minor loss. Furthermore, the installation of the turbine results in a breakdown of symmetry in the engine oscillation mode. To maintain symmetry and improve system design, future developments must consider the installation of a turbine in each unit. These findings can pave the way to the design of liquid piston Stirling engines and their applications in thermal energy conversion., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).)

Background/purpose: Various biofeedback stimulation techniques for managing sleep bruxism (SB) have recently emerged; however, the effect of the successive application of vibratory feedback stimulation has not been clarified. This study aimed to elucidate the effect of vibration feedback stimulation via an oral appliance (OA) on SB., Materials and Methods: This prospective, single-arm, open-label intervention study included 20 participants diagnosed with "definite" SB who wore a specially designed OA for 98 nights at home. A force-based SB detection system triggered a vibrator attached to the OA. Vibratory stimulation was withheld during the first 3-week adaptation period (weeks 1-3), applied during the 9-week stimulation period (weeks 4-12), and withheld again during the post-stimulation period (weeks 13-14). The number and duration of SB events per hour of sleep were calculated based on piezoelectric signals recorded with the OA-based vibration feedback device and compared between weeks 3 and 4, 8, 12, and 14 and between weeks 12 and 14 using the Friedman test (post-hoc test with Bonferroni correction)., Results: The duration of SB events significantly decreased after vibratory stimulation (weeks 3 versus 4, 8, and 12: P  < 0.001, P  = 0.026, and P  = 0.033, respectively) and then significantly increased upon cessation of vibratory stimulation after the stimulation period (weeks 12 versus 14: P  < 0.001)., Conclusion: Contingent vibratory stimulation through an OA-based vibration feedback device may suppress SB-related masticatory muscle activity continuously for 9 weeks and may be an effective alternative for managing SB., (© 2024 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V.)

Objective: This study aimed to investigate the causes of lumboperitoneal (LP) shunt failure and determine risk factors for lumbar catheter fracture., Methods: We retrospectively investigated 149 patients who underwent LP shunting in our hospital between January 2012 and March 2023. Shunt reconstruction occurred in 22 patients (14.8%). Among these, cause of failure was lumbar catheter fracture in 5 (22.7%). Patient backgrounds, cause of LP shunt failure, surgical technique factors, and anatomical characteristics were extracted for comparative analysis and risk factors of lumbar catheter fracture were analyzed., Results: Compared with the no reoperation group (n = 127), patients in the lumbar catheter fracture tended to be younger (63 ± 20 vs. 72 ± 11 years) and favorable neurologic status (modified Rankin scale score ≤2) after initial LP shunt; however, the differences were not significant. Lumbar lordosis was significantly higher in the lumbar catheter fracture group (52.7°± 14.8° vs. 37.1°± 12.3°; P = 0.0067)., Conclusions: Excessive lumbar lordosis is a risk factor for lumbar catheter fracture in patients undergoing LP shunting. Younger age and higher level of postoperative activities of daily living might also be associated with lumbar catheter fracture., (Copyright © 2024 Elsevier Inc. All rights reserved.)

We present a case of pontine infarction caused by subclavian steal phenomenon (SSP) due to subclavian artery stenosis (SAS) and an arteriovenous shunt in the forearm in a 74-year-old man with hemodialysis and stenting for SAS with improvement of SSP. He developed dysarthria during dialysis. He was admitted to our hospital and diagnosed with a pontine infarction. As the basilar artery appeared to be occluded on magnetic resonance angiography, an emergency diagnostic angiography was performed. Aortagram showed severe stenosis of the left subclavian artery. Right vertebral artery (VA) angiogram revealed retrograde arterial blood flow from the right VA to the left VA via the VA union, which suggested SSP. In addition, the steal was augmented by an ipsilateral hemodialysis arteriovenous shunt. Percutaneous subclavian artery stenting was performed 12 days later, and there was no recurrence of symptoms in the follow-up period. To our knowledge, this study is the first to report a patient with SSP who developed a pontine infarction due to SAS and an arteriovenous shunt during hemodialysis and who underwent subclavian artery stenting and had a good outcome., Competing Interests: The authors declare no conflict of interest., (© 2024 The Japan Neurosurgical Society.)

Bifrontal craniotomy frequently involves opening the frontal sinus and mucosal injury. We report a new technique for mucosal repair in the frontal sinus using surgical titanium microclips. Six consecutive patients who underwent bifrontal craniotomy with frontal sinus exposure and mucosal injury underwent mucosal repair using surgical titanium microclips between April 2019 and August 2022. In all cases, the frontal sinus mucosa was peeled from the inner walls of the frontal sinus to ensure sufficient mucosal margin for clipping using ORBEYE. The repair was accomplished with the microclips in all cases. We also sealed the mucosal wound using fibrin glue and sufficiently filled the frontal sinus with bone debris, resulting in zero incidence of postoperative liquorrhea in all cases. Repairing the mucosa using surgical titanium microclips using ORBEYE may be a simple and quick technique when the frontal sinus mucosa is injured during craniotomy.

The advent of Artificial Intelligence (AI) is fostering the development of innovative methods of communication and collaboration. Integrating AI into Information and Communication Technologies (ICTs) is now ushering in an era of social progress that has the potential to empower marginalized groups. This transformation paves the way to a digital inclusion that could qualitatively empower the online presence of women, particularly in conservative and male-dominated regions. To explore this possibility, we investigated the effect of integrating conversational agents into online debates encompassing 240 Afghans discussing the fall of Kabul in August 2021. We found that the agent leads to quantitative differences in how both genders contribute to the debate by raising issues, presenting ideas, and articulating arguments. We also found increased ideation and reduced inhibition for both genders, particularly females, when interacting exclusively with other females or the agent. The enabling character of the conversational agent reveals an apparatus that could empower women and increase their agency on online platforms., (© 2023. Springer Nature Limited.)

Background: The immune checkpoint programmed cell death 1 (PD-1): PD-1 ligand 1 (PD-L1) pathway plays a crucial role in maintaining immune tolerance and preventing tissue damages by excessive immune responses. PD-L1 is physiologically expressed and upregulated in keratinocytes (KCs) in the oral cavity. We here investigated the contribution of PD-L1 that was overexpressed in gingival basal KCs in a ligature-induced periodontitis model., Methods: Wild-type (WT) BALB/c and K14/PD-L1 transgenic (tg) mice, in which PD-L1 was overexpressed in basal KCs under control of the keratin 14 promoter, were used. To induce periodontitis, a 9-0 silk ligature was placed around the upper right second molar, and lipopolysaccharide from Porphyromonas gingivalis was applied on the suture. Gingival tissues were collected on day 7, after which histological analyses were performed, including by hematoxylin and eosin and tartrate-resistant acid phosphate staining (TRAP) and quantitative PCR for proinflammatory cytokines and bone metabolism-related genes. Alveolar bone loss at 7 weeks after ligature placement was assessed by micro-computed tomography analysis., Results: PD-L1 was overexpressed in the basal KCs of all gingival epithelia in K14/PD-L1tg mice. Early ligature-induced periodontal inflammation, as assessed based on histological changes, elevation of proinflammatory cytokine (IL-1β, IL-6, TNF-α) expression, periodontal ligament degeneration, and osteoclastogenesis as assessed by Rankl and Opg expression and TRAP+ cells, was markedly impaired in K14/PD-L1tg mice. Alveolar bone resorption at a late time point was also clearly minimized in K14/PD-L1tg mice., Conclusion: Overexpression of PD-L1 in gingival basal keratinocytes in K14/PD-L1tg mice reduces periodontal inflammation and alveolar bone resorption in a ligature-induced periodontitis model., (© 2021 The Authors. Journal of Periodontology published by Wiley Periodicals LLC on behalf of American Academy of Periodontology.)

During palatogenesis, the palatal shelves first grow vertically on either side of the tongue before changing their direction of growth to horizontal. The extracellular matrix (ECM) plays an important role in these dynamic changes in palatal shelf morphology. Tenascin-C (TNC) is an ECM glycoprotein that shows unique expression in the posterior part of the palatal shelf, but little is known about the regulation of TNC expression. Since transforming growth factor-beta-3 (TGF-β3) and sonic hedgehog (SHH) signaling are known to play important roles in palatogenesis, we investigated whether TGF-β3 and SHH are involved in the regulation of TNC expression in the developing palate. TGF-β3 increased the expression of TNC mRNA and protein in primary mouse embryonic palatal mesenchymal cells (MEPM) obtained from palatal mesenchyme dissected at embryonic day 13.5-14.0. Interestingly, immunohistochemistry experiments revealed that TNC expression was diminished in K14-cre ; Tgfbr2 fl/fl mice that lack the TGF-β type II receptor in palatal epithelial cells and exhibit cleft soft palate, whereas TNC expression was maintained in Wnt1-cre ; Tgfbr2 fl/fl mice that lack the TGF-β type II receptor in palatal mesenchymal cells and exhibit a complete cleft palate. SHH also increased the expression of TNC mRNA and protein in MEPM cells. However, although TGF-β3 up-regulated TNC mRNA and protein expression in O9-1 cells (a cranial neural crest cell line), SHH did not. Furthermore, TGF-β inhibited the expression of osteoblastic differentiation markers (osterix and alkaline phosphatase) and induced the expression of fibroblastic markers (fibronectin and periostin) in O9-1 cells, whereas SHH did not affect the expression of osteoblastic and fibroblastic markers in O9-1 cells. However, immunohistochemistry experiments showed that TNC expression was diminished in the posterior palatal shelves of Shh -/+ ; MFCS4 +/- mice, which have deficient SHH signaling in the posterior palatal epithelium. Taken together, our findings support the proposal that TGF-β and SHH signaling in palatal epithelium co-ordinate the expression of TNC in the posterior palatal mesenchyme through a paracrine mechanism. This signal cascade may work in the later stage of palatogenesis when cranial neural crest cells have differentiated into fibroblast-like cells. The spatiotemporal regulation of ECM-related proteins by TGF-β and SHH signaling may contribute not only to tissue construction but also to cell differentiation or determination along the anterior-posterior axis of the palatal shelves., (Copyright © 2020 Ohki, Oka, Ogata, Okuhara, Rikitake, Toda-Nakamura, Tamura, Ozaki, Iseki and Sakai.)

The tongue is a highly specialised muscular organ with a complex anatomy required for normal function. We have utilised multiple genetic approaches to investigate local temporospatial requirements for sonic hedgehog (SHH) signalling during tongue development. Mice lacking a Shh cis -enhancer, MFCS4 ( ShhMFCS4/- ), with reduced SHH in dorsal tongue epithelium have perturbed lingual septum tendon formation and disrupted intrinsic muscle patterning, with these defects reproduced following global Shh deletion from E10.5 in pCag - CreERTM; Shhflox/flox embryos. SHH responsiveness was diminished in local cranial neural crest cell (CNCC) populations in both mutants, with SHH targeting these cells through the primary cilium. CNCC-specific deletion of orofaciodigital syndrome 1 ( Ofd1 ), which encodes a ciliary protein, in Wnt1-Cre; Ofdfl/Y mice led to a complete loss of normal myotube arrangement and hypoglossia. In contrast, mesoderm-specific deletion of Ofd1 in Mesp1-Cre; Ofdfl/Y embryos resulted in normal intrinsic muscle arrangement. Collectively, these findings suggest key temporospatial requirements for local SHH signalling in tongue development (specifically, lingual tendon differentiation and intrinsic muscle patterning through signalling to CNCCs) and provide further mechanistic insight into the tongue anomalies seen in patients with disrupted hedgehog signalling., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2019. Published by The Company of Biologists Ltd.)

The cranial base is a structure mainly formed through endochondral ossification and integrated into the craniofacial complex, which acts as an underlying platform for the developing brain. Foxc1 is an indispensable regulator during intramembranous and endochondral ossification. In this study, we found that the spontaneous loss of Foxc1 function in a mouse (congenital hydrocephalous), Foxc1 ch/ch , demonstrated the anterior cranial base defects, including unossified presphenoid and lack of middle part of the basisphenoid bone. Hypoplastic presphenoid primordial cartilage (basal portion of the trabecular cartilage [bTB]) and a lack of the middle part of basisphenoid primordial cartilage (the hypophyseal cartilage) were consistently observed at earlier developmental stage. Foxc1 was expressed robustly and ubiquitously in undifferentiated mesenchyme of the cranial base-forming area in E11.0 wild-type fetuses. Once chondrogenesis commenced, the expression was downregulated and later limited to the perichondrium. Detection of transcripts of Collagen type2 A1 (Col2a1) revealed that both bTB and the anterior part of the hypophyseal cartilage developing anterior to the persistent epithelial stalk of the anterior lobe of the pituitary gland were suppressed in the Foxc1 ch/ch . Proliferation activity of chondrocyte precursor cells was higher in the Foxc1 ch/ch . Loss of Foxc1 function only in the neural crest cell lineage (Wnt1-cre;Foxc1 ch/flox ) showed ossification of the posterior part of the hypophyseal cartilage derived from the mesoderm. These findings suggest that Foxc1 is an important regulator to further chondrogenesis and initiate the ossification of the presphenoid and basisphenoid bones., (© 2018 Japanese Teratology Society.)

Aim: Although hyponatremia is associated with a poor prognosis in liver cirrhosis, little is known about the clinical significance of serum sodium concentration in cirrhosis in Japan. This study investigated associations of mortality in Japanese cirrhosis patients taking conventional diuretics with serum sodium concentration and other clinical characteristics., Methods: A total of 171 consecutive patients with cirrhosis who were taking diuretic medication were enrolled retrospectively. We determined the prevalence of low serum sodium concentration and searched for associations with age, sex, etiology, complications of cirrhosis, liver function tests and Model for End-Stage Liver Disease (MELD) and MELD-Na scores. The predictive ability of sodium level on mortality was also investigated., Results: Median serum sodium concentration was 139 mEq/L (interquartile range, 137-141). Only eight of 171 (4.7%) patients had low serum sodium (<130 mEq/L). Median MELD-Na score was 10.5 (interquartile range, 8.0-14.3). Cumulative survival rates were significantly lower in patients with Na of less than 139 mEq/L or MELD-Na score of 10.5 or more (log-rank test, P = 0.017 and P = 0.0002, respectively). Several liver function tests, MELD and MELD-Na scores, and the incidence of ascites were all significantly associated with patients having Na of less than 139 mEq/L., Conclusion: Serum sodium concentration below 139 mEq/L and MELD-Na score above 10.5 may be predictive markers for mortality in patients with cirrhosis despite being within normal ranges. These markers may help to better assess and manage the prognosis of patients with cirrhosis in Japan., (© 2014 The Japan Society of Hepatology.)

Background: The brain vascular system arises from the perineural vascular plexus (PNVP) which sprouts radially into the neuroepithelium and subsequently branches off laterally to form a secondary plexus in the subventricular zone (SVZ), the subventricular vascular plexus (SVP). The process of SVP formation remains to be fully elucidated. We investigated the role of Foxc1 in early stage vascular formation in the ventral telencephalon., Results: The Foxc1 loss of function mutant mouse, Foxc1(ch/ch) , showed enlarged telencephalon and hemorrhaging in the ventral telencephalon by embryonic day 11.0. The mutant demonstrated blood vessel dilation and aggregation of endothelial cells in the SVZ after the invasion of endothelial cells through the radial path, which lead to failure of SVP formation. During this early stage of vascular development, Foxc1 was expressed in endothelial cells and pericytes, as well as in cranial mesenchyme surrounding the neural tube. Correspondingly, abnormal deposition pattern of basement membrane proteins around the vessels and increased strong Vegfr2 staining dots were found in the aggregation sites., Conclusions: These observations reveal an essential role for Foxc1 in the early stage of vascular formation in the telencephalon., (© 2015 Wiley Periodicals, Inc.)

Aim: We sought to clarify the associations between serum cytokines and chemokines, hepatitis B surface antigen (HBsAg), hepatitis B core-related antigen (HBcrAg), and hepatitis B virus (HBV) DNA and response to entecavir therapy in chronic hepatitis B., Methods: We analyzed six cytokines (interleukin [IL]-2, IL-6, IL-10, IL-12p70, IL-21 and IL-22) and five chemokines (CCL2, CCL3, CXCL9, CXCL10 and CXCL11) before and at 6, 12 and 24 months during entecavir therapy in 48 chronic hepatitis B patients. Quantitative measurement of HBsAg, HBcrAg and HBV DNA was performed. A virological response (VR) was defined as serum HBV DNA of less than 2.1 log copies/mL by treatment month 24., Results: Thirty-nine patients (81%) achieved a VR. Serum IL-6 (P = 0.031), CXCL-9 (P = 0.002), and CXCL-10 (P = 0.001) were high in chronic HBV and correlated positively with transaminases and bilirubin. Before treatment, elevated IL-22 (P = 0.031) and lower HBsAg (P = 0.001) and HBcrAg (P < 0.001), but not HBV DNA, were associated with a favorable treatment outcome. In multivariate analysis, high IL-22 (hazard ratio = 13.67, P = 0.046) and low HBcrAg (hazard ratio = 10.88, P = 0.048) were independently associated with a VR. The levels of IL-22 (P < 0.001), HBsAg (P < 0.001), and HBcrAg (P < 0.001) all decreased from baseline to 24 months of treatment in virological responders., Conclusion: Serum IL-22 and HBcrAg are predictive markers of a VR to entecavir therapy in patients with chronic hepatitis B., (© 2013 The Japan Society of Hepatology.)

The frontal and parietal bones form the major part of the calvarium and their primordia appear at the basolateral region of the head and grow apically. A spontaneous loss of Foxc1 function mutant mouse, congenital hydrocephalus (Foxc1(ch/ch)), results in congenital hydrocephalus accompanied by defects in the apical part of the skull vault. We found that during the initiation stage of apical growth of the frontal bone primordium in the Foxc1(ch/ch) mouse, the Runx2 expression domain extended only to the basal side and bone sialoprotein (Bsp) and N-cadherin expression domains appeared only in the basal region. Fluorescent dye (DiI) labeling of the frontal primordium by ex-utero surgery confirmed that apical extension of the frontal bone primordium of the mouse was severely retarded, while extension to the basal side underneath the brain was largely unaffected. Consistent with this observation, decreased cell proliferation activity was seen at the apical tip but not the basal tip of the frontal bone primordium as determined by double detection of Runx2 transcripts and BrdU incorporation. Furthermore, expression of the osteogenic-related genes Bmp4 and-7 was observed only in the basal part of the meninges during the initiation period of primordium growth. These results suggest that a loss of Foxc1 function affects skull bone formation of the apical region and that Bmp expression in the meninges might influence the growth of the calvarial bone primordium., (© 2014 Japanese Teratology Society.)

An adolescent girl presented with inappetence. Upper gastrointestinal endoscopy showed rough and cracked mucosa at the gastric antrum with a scarred duodenal ulcer, and a biopsy sample demonstrated abundant eosinophils. We therefore diagnosed the patient as having eosinophilic gastroenteritis. Eradication therapy for Helicobacter pylori (H. pylori) did not improve her symptoms; however, proton pump inhibitor therapy was effective in resolving her chief complaints. There are several reports of eosinophilic gastroenteritis complicated with H. pylori infection in which the association between eradication therapy and the patient's symptoms is unclear. In the present case, the patient's symptoms did not improve with eradication therapy, and there appeared to be no relationship between the two.

Fibroblast growth factor (FGF) signaling is involved in skeletal development. Among total 22 FGFs, it is suggested that FGF18 functions in promotion of osteoblast differentiation. In order to elucidate the mechanism of FGF18-dependent acceleration of osteogenesis, we implanted rhFGF18 soaked beads over mouse fetal coronal sutures using ex-utero surgery. The coronal suture area comprises the peripheries of the developing frontal and parietal bones, separated by the sutural mesenchyme. rhFGF18 accelerated osteogenesis by promoting connection of the frontal and parietal bone domains, resulting in elimination of the sutural mesenchyme. Expression of Fgf receptors, Fgfr1, -2 and -3 involved in skeletal development, was maintained or upregulated in the developing bone domains, consistent with enhanced osteogenesis. Bone morphogenetic protein (Bmp) 2 was specifically upregulated in the skeletogenic layer and the application of Bmp antagonist, rmNoggin, inhibited rhFGF18-dependent upregulation of osteoblast markers. These results suggest that FGF18 accelerates osteogenesis by upregulation of Bmp2 as well as maintenance or upregulation of Fgfr1, -2 and -3 expression in osteoblasts., (© 2013 The Authors. Congenital Anomalies © 2013 Japanese Teratology Society.)

The upper lip is formed by the fusion of facial processes, a process in which many genetic and environmental factors are involved. Embryonic hypoxia is induced by uterine anemia and the administration of vasoconstrictors during pregnancy. To define the relationship between hypoxia and upper lip formation, hypoxic conditions were created in a whole embryo culture system. Hypoxic embryos showed a high frequency of impaired fusion, reflecting failure in the growth of the lateral nasal process (LNP). In hypoxic embryos, cell proliferation activity in the LNP mesenchyme was decreased following downregulation of genes that are involved in lip formation. We also observed upregulation of vascular endothelial growth factor expression along with the induction of apoptosis in the LNP. These results suggest that embryonic hypoxia during lip formation induces apoptosis in physiologically hypoxic regions, hypoxia-induced gene expression and downregulation of the genes involved in maxillofacial morphogenesis as immediate responses, followed by reduction of mesenchymal cell proliferation activity, resulting in insufficient growth of the facial processes., (Copyright © 2012 Wiley Periodicals, Inc.)

Tenascin-W is a tenascin family member that forms part of a complex extracellular matrix, and previous studies have suggested its association with osteogenesis. In the present study we investigated the roles of tenascin-W in osteogenesis. We found that tenascin-W is expressed in osteoblasts at the edge of the developing bone domain prior to mineralization in mouse fetuses. Expression of tenascin-W was induced during the course of mineralization of the Kusa-A1 osteoblast cell line. In the interfrontal suture of postnatal mice, the anterior portion remains patent and the posterior portion closes by 4 weeks of age. Tenascin-W expression was downregulated at 1 week of age in the posterior frontal suture, whereas in the anterior suture, expression was maintained until the mice reached 4 weeks of age. Fibroblast growth factor 2 (FGF2)-bead application to the mouse fetal skull by ex-utero surgery accelerated osteoblast differentiation, but inhibited mineralization with a downregulation of tenascin-W expression. These results suggest that tenascin-W is involved in osteoblast maturation (i.e. mineralization).

Objective: The object of this study was to elucidate the kinetics of receptor activator of NFkB ligand (RANKL), RANK, osteoprotegerin (OPG), and cytokine expressions in experimentally induced rat periapical lesions., Study Design: The mRNA expressions of RANKL, RANK, OPG, and cytokines in experimentally induced rat periapical lesions were evaluated by real-time PCR. The lesions were induced in male Wistar rats (n = 48, 5 weeks of age) by unsealed pulp exposure of the lower first molars., Results: Expression of RANKL was up-regulated at the beginning of lesion expansion, and expression ratio of RANKL against OPG, a competitor of RANKL, peaked at 2 and 3 weeks. Expression of inflammatory cytokines, such as TNF-alpha, IL-1alpha, and IL-1beta also increased at this stage, suggesting contribution of synergic effects of RANKL and proinflammatory cytokine signaling to lesion expansion. Most of RANKL+ cells were fibroblastic, but few of them were T cells., Conclusion: Expression of RANKL and proinflammatory cytokines was correlated with periapical lesion expansion.

Both induction and inhibition of "preferential enrichment", an unusual symmetry-breaking enantiomeric-resolution phenomenon observed upon simple recrystallization of a certain kind of racemic crystals from organic solvents, have been successfully achieved by controlling the mode of the polymorphic transition during crystallization with appropriate seed crystals. Such control of the polymorphic transition can be interpreted in terms of a novel phenomenon consisting of 1) the adsorption of prenucleation aggregates, 2) the heterogeneous nucleation and crystal growth of a metastable crystalline form, and 3) the subsequent polymorphic transition into the more stable form; these three processes occur on the same surface of a seed crystal. We refer to this phenomenon as an "epitaxial transition", which has been confirmed by means of in situ attenuated total reflection (ATR) FTIR spectroscopy in solution and the solid state, differential scanning calorimetry (DSC) measurements of the deposited crystals, and X-ray crystallographic analysis of the single crystals or the direct-space approach employing the Monte Carlo method with the Rietveld refinement for the structure solution from the powder X-ray diffraction data.