Multicenter study comparing EUS-guided hepaticogastrostomy and ERCP for malignant biliary obstruction in patients with accessible papillae.

BACKGROUND: One advantage of endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is that it is difficult for reflux cholangitis, caused by duodenal pressure increasing due to duodenal obstruction, to occur. In addition, since stent deployment is performed away from the malignant stricture site, longer stent patency than with endoscopic retrograde cholangiopancreatography (ERCP) may be obtained. However, no study has previously compared EUS-HGS and ERCP for patients without duodenal obstruction or surgically altered anatomy. The aim of the present study was to compare clinical outcomes between EUS-HGS and ERCP in normal anatomy patients without duodenal obstruction. METHOD: In the ERCP group, patients who initially underwent biliary drainage were included. In the EUS-HGS group, patients who underwent EUS-HGS due to failed biliary cannulation were included. Patients with an inaccessible papilla, such as with surgically altered anatomy or duodenal obstruction, were excluded. RESULTS: A total of 314 patients who underwent ERCP and EUS-HGS were enrolled in this study. Of the 314 patients, 289 underwent biliary stenting under ERCP guidance, and 25 patients underwent biliary stenting under EUS-HGS. After propensity score-matching analysis, the adverse event rate tended to be lower in the EUS-HGS group than in the ERCP group. Although overall survival was not significantly different between the EUS-HGS and ERCP groups (p = .228), stent patency was significantly longer in the EUS-HGS group (median 366.0 days) than in the ERCP group (median 76.5 days). CONCLUSIONS: EUS-HGS had a lower adverse event rate, shorter procedure time, and longer stent patency than ERCP in cases of normal anatomy without duodenal obstruction.

Influence of feeding a soft diet on proteoglycan expression in rat temporomandibular joint discs.

OBJECTIVES: Extracellular matrix components play a significant role in maintaining tissue integrity and pathological processes of the temporomandibular joint (TMJ). This study aimed to evaluate the influence of a soft diet on the mRNA expression of proteoglycans and glycosaminoglycans (GAGs) linked to proteoglycan core proteins in rat TMJ discs. METHODS: Thirty 4-week-old male Wistar rats were assigned to one of two groups: a control group fed a regular pellet diet and a soft diet group fed a powdered diet for 4 weeks. The mRNA expression levels of 12 proteoglycans in TMJ discs were evaluated using real-time polymerase chain reaction (PCR). In addition, histomorphometric and biochemical analyses were performed to evaluate the thickness and deoxyribonucleic acid (DNA), GAG, and water content of the TMJ discs. RESULTS: The TMJ disc thickness in the anterior, intermediate, and posterior bands decreased significantly in the soft diet group. The GAG content decreased significantly in the soft-diet group, whereas no significant differences in DNA content or water content ratio were observed between the groups. Real-time PCR indicated that the expression levels of aggrecan, versican, biglycan, decorin, fibromodulin, lumican, and chondroadherin decreased in the soft diet group. The expression levels of all versican isoforms decreased in the soft diet group. CONCLUSIONS: These results indicate that the biomechanical environment of the TMJ caused by a soft diet is closely related to the expression of proteoglycans in TMJ discs, which may eventually increase the fragility of the TMJ discs.

Utility of Contrast-Enhanced Harmonic Endoscopic Ultrasonography to Diagnose Pancreaticobiliary Maljunction.

BACKGROUND: Detection of a common channel outside the duodenal wall is important in diagnosing pancreaticobiliary maljunction (PBM). The present study evaluated the utility of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) in diagnosing PBM. METHODS: This single-center retrospective study enrolled 45 patients who were diagnosed with PBM or high confluence of pancreatobiliary ducts (HCPBD) between January 2007 and December 2021. The diagnostic sensitivities of contrast-enhanced computed tomography (CE-CT), magnetic resonance imaging (MRI), and CH-EUS for diagnosing PBM were analyzed. Imaging findings were evaluated by two reviewers blinded to the clinicopathological results. RESULTS: Based on diagnostic criteria, 33 patients were diagnosed with PBM and 12 with HCPBD. Compared with the patients with HCPBD, those with PBM had significantly longer common channel (12.5 mm vs. 8.1 mm, P = 0.018) and common bile duct (13.0 mm vs. 8.6 mm, P = 0.049) lengths. The κ-coefficients for differentiating PBM and HCPBD were 0.871 between CE-CT and MRI, 0.330 between CE-CT and CH-EUS, and 0.611 between MRI and CH-EUS. The diagnostic sensitivity of CH-EUS (95.2%) was higher than that of CE-CT (83.3%) and MRI (82.8%), although the differences were not statistically significant. CONCLUSION: CH-EUS may be useful for the diagnosis of PBM.

Three-Dimensional Evaluation of Treatment Effects and Post-Treatment Stability of Maxillary Molar Intrusion Using Temporary Anchorage Devices in Open Bite Malocclusion.

Background: We investigated treatment outcomes and post-treatment stability in 10 patients with an anterior open bite and nonsurgical orthodontics. Methods: The patients underwent maxillary molar intrusion using temporary anchorage devices (TADs) to deepen the overbite due to mandibular autorotation. Lateral cephalograms and dental cast models were obtained before treatment (T0), immediately after it (T1), and >1 year after it (T2). Skeletal and dental cephalometric changes and three-dimensional movements of the maxillary dentitions were evaluated. Results: At T0, cephalometric analysis indicated that patients had skeletal class I with tendencies for a class II jaw relationship and a skeletal open bite. During active treatment (T0 to T1), the maxillary first molar intruded by 1.6 mm, the mandibular first molar extruded by 0.3 mm, the Frankfort-mandibular plane angle decreased by 1.1°, and the overbite increased by 4.1 mm. Statistically significant changes were observed in the amount of vertical movement of the maxillary first molar, Frankfort-mandibular plane angle, and overbite. Three-dimensional (3D) dental cast analysis revealed that the maxillary first and second molars intruded, whereas the anterior teeth extruded, with the second premolar as an infection point. In addition, the maxillary molar was tipped distally by 2.9° and rotated distally by 0.91°. Statistically significant changes were observed in the amount of vertical movement of the central incisor, lateral incisor, canine and first molar, and molar angulation. From T1 to T2, no significant changes in cephalometric measurements or the 3D position of the maxillary dentition were observed. The maxillary and mandibular dentitions did not significantly change during post-treatment follow-up. Conclusions: Maxillary molar intrusion using mini-screws is an effective treatment for open bite correction, with the achieved occlusion demonstrating 3D stability at least 1 year after treatment.

Distribution of alpha-synuclein in rat salivary glands.

Expression of alpha-synuclein (Syn), a presynaptic neuronal protein, was immunohistochemically examined in intact rat submandibular, sublingual, and lingual glands. The submandibular gland contained abundant periductal Syn-immunoreactive (-ir) nerve fibers. Abundant Syn-ir varicosities were present in acini of the sublingual and serous lingual glands. By confocal laser scanning microscopy, Syn-ir nerve fibers around smooth muscle actin (SMA)-ir cells alone were infrequent; however, those around aquaporin-5 (AQP5)-ir cells alone and both SMA- and AQP5-ir cells were abundant in the sublingual and serous lingual glands. SMA-ir cells were occasionally immunoreactive for toll-like receptor 4, a Syn receptor. Syn-ir nerve fibers contained tyrosine hydroxylase (TH) in the submandibular gland and choline acetyltransferase (ChAT) in all examined salivary glands. In the superior cervical (SCG), submandibular, and intralingual ganglia, sympathetic and parasympathetic neurons co-expressed Syn with TH and ChAT, respectively. SCG neurons innervating the submandibular gland contained mostly Syn. In the thoracic spinal cord, 14.7% of ChAT-ir preganglionic sympathetic neurons co-expressed Syn. In the superior salivatory nucleus, preganglionic parasympathetic neurons projecting to the lingual nerve co-expressed Syn and ChAT. The present findings indicate that released Syn acts on myoepithelial cells. Syn in pre- and post-ganglionic neurons may regulate neurotransmitter release and salivary volume and composition.

Three-dimensional morphologic analysis of the maxillary alveolar bone after anterior tooth retraction with temporary anchorage devices.

OBJECTIVES: To investigate three-dimensional (3D) morphologic changes in the alveolar bone around the maxillary central incisors of patients who underwent premolar extraction and subsequent anterior tooth retraction using temporary anchorage devices (TADs). MATERIALS AND METHODS: The subjects consisted of 16 patients with bimaxillary protrusion. The maxillary anterior teeth were retracted using sliding or loop mechanics and TADs for anchorage reinforcement. Cephalograms and computed tomography scans taken pretreatment and posttreatment were registered with respect to the palatal structures. The movement of the maxillary central incisors and morphologic changes in the anterior alveolar bone were evaluated quantitatively. RESULTS: Displacement in the palatal direction was observed in the alveolar bone around the incisors and the interdental septum. The displacement and bone remodeling/tooth movement ratio were larger on the labial side than the palatal side, and decreased progressively from the crest to apex level. The bone thickness was significantly increased on the labial side and decreased on the palatal side. CONCLUSIONS: Regional differences exist in morphologic changes of the alveolar bone during anterior tooth retraction using TADs. Attention should be paid to the crest region of the palatal alveolar bone because of its small original thickness and low remodeling activity.

The role of TRPV2 as a regulator on the osteoclast differentiation during orthodontic tooth movement in rats.

When orthodontic forces are applied to teeth, bone remodeling, which consists of bone resorption and bone formation, occurs around the teeth. Transient receptor potential vanilloid 2 (TRPV2) is a cation channel expressed in various cell types that responds to various stimuli, including mechanical stress, and involved in calcium oscillations during the early stages of osteoclast differentiation. However, in vivo expression of TRPV2 in osteoclasts has not yet been reported, and temporo-spatial expression of TRPV2 during osteoclast differentiation is unclear. In this study, we examined the TRPV2 expression during experimental tooth movement and assessed the effect of TRPV2 on osteoclast differentiation. TRPV2 was detected on day 1 after experimental tooth movement on the compression side, and the number of TRPV2-expressing cells significantly increased on day 7. These TRPV2-expressing cells had a single, or multiple nuclei and were positive for TRAP activity. Consistent with these in vivo findings, in vitro experiments using RAW264.7 osteoclast progenitor cells showed that TRPV2 mRNA was increased at the early stage of osteoclast differentiation and maintained until the late stage. Furthermore, a TRPV2 channel selective antagonist significantly inhibited osteoclast differentiation. These findings suggest that TRPV2 may have a regulatory role in osteoclast differentiation during orthodontic tooth movement.

Vibration accelerates orthodontic tooth movement by inducing osteoclastogenesis via transforming growth factor-ß signalling in osteocytes.

BACKGROUND: We previously found the conditions of supplementary vibration that accelerated tooth movement and induced bone resorption in an experimental rat tooth movement model. However, the molecular biological mechanisms underlying supplementary vibration-induced orthodontic tooth movement are not fully understood. Transforming growth factor (TGF)-ß upregulates osteoclastogenesis via induction of the receptor activator of nuclear factor kappa B ligand expression, thus TGF-ß is considered an essential cytokine to induce bone resorption. OBJECTIVES: The aim of this study is to examine the role of TGF-ß during the acceleration of orthodontic tooth movement by supplementary vibration. MATERIALS AND METHODS: In experimental tooth movement, 15 g of orthodontic force was loaded onto the maxillary right first molar for 28 days. Supplementary vibration (3 g, 70 Hz) was applied to the maxillary first molar for 3 min on days 0, 7, 14, and 21. TGF-ß receptor inhibitor SB431542 was injected into the submucosal palatal and buccal areas of the maxillary first molars once every other day. The co-culture of RAW264.7 cells and MLO-Y4 cells was used as an in vitro osteoclastogenesis model. RESULTS: SB431542 suppressed the acceleration of tooth movement and the increase in the number of osteoclasts by supplementary vibration in our experimental rat tooth movement model. Immunohistochemical analysis showed supplementary vibration increased the number of TGF-ß1-positive osteocytes in the alveolar bone on the compression side during the experimental tooth movement. Moreover, vibration-upregulated TGF-ß1 in MLO-Y4 cells induced osteoclastogenesis. CONCLUSIONS: Orthodontic tooth movement was accelerated by supplementary vibration through the promotion of the production of TGF-ß1 in osteocytes and subsequent osteoclastogenesis.

A comparative study on cephalometric differences in maxillofacial morphology between skeletal Class III cases with and without acromegaly: a pilot study.

OBJECTIVES: The most typical maxillofacial feature of patients with acromegaly is mandibular protrusion. This study aimed to determine differences in maxillofacial morphology between skeletal Class III patients with and without acromegaly using cephalometric analysis. METHODS: Cephalograms of 37 patients with acromegaly (Acro), 37 age-matched non-acromegalic patients with skeletal Class III malocclusion (C-III), and 37 age-matched Class I malocclusion patients (C-I; control) were retrospectively collected. The skeletal and dental morphology of each group was analyzed using cephalometric analysis, which included linear and angular measurements and facial profilograms. In addition, we analyzed diagnostic performance and cutoff values for discriminating acromegaly from skeletal Class III malocclusion using receiver operating characteristic (ROC) curve analysis. RESULTS: The mandibular ramus height was larger in the Acro group than in the other groups. The increase in L1/MP in the Acro group, which represented labial inclination of the mandibular central incisors, was the most characteristic feature in this study. ROC curve analysis indicated that a cutoff value of 88.4° for L1/MP had the highest diagnostic performance in discriminating acromegaly from non-acromegalic Class III malocclusion. CONCLUSIONS: Acromegaly was characterized by a greater degree of bimaxillary prognathism than was non-acromegalic Class III malocclusion. Focusing on labial inclination of the mandibular central incisors would be the most useful way to differentiate acromegaly from non-acromegalic Class III malocclusion.

Distribution of alpha-synuclein in the rat cranial sensory ganglia, and oro-cervical regions.

BACKGROUND: Alpha-synuclein (Syn), an unfolded soluble cytosolic protein, is known as a disease-associated protein in the brain. However, little is known about distribution of this protein in the peripheral nervous system. In this study, expression of Syn was investigated in the sensory ganglia of the cranial nerves V, IX and X. METHODS: To analyze distribution of Syn and its co-expression with calcitonin gene-related peptide (CGRP) or the transient receptor potential cation channel subfamily V member 1 (TRPV1), immunohistochemical techniques were used in the rat cranial sensory ganglia and their peripheral tissues. RESULTS: Syn-immunoreactive (-ir) neurons were abundant in the sensory ganglia of the petrosal (56.7%), jugular (28.3%) and nodose ganglia (82.5%). These neurons had small to medium-sized cell bodies (petrosal, mean ± S.D. = 667.4 ± 310.8 µ m2; jugular, 625.1 ± 318.4 µ m2; nodose, 708.3 ± 248.3 µ m2), and were distributed throughout the ganglia. However, the trigeminal ganglion was mostly free of Syn-ir neurons. By double and triple immunofluorescence staining, Syn-ir neurons co-expressed CGRP and TRPV1 in the petrosal and jugular ganglia. Syn-immunoreactivity was expressed by nerve fibers in the epithelium and taste bud of oral and cervical viscerae. These nerve fibers were abundant in the naso-pharynx, epiglottis and laryngeal vestibule. Some taste bud cells were also immunoreactive for Syn. In addition, Syn-ir nerve fibers were detected in the vicinity of macrophages, dendritic cells and Langerhans cells. CONCLUSIONS: Syn was abundant in the visceral sensory neurons but not in somatic sensory neurons. This protein may play a role in nociceptive and chemosensory transduction in the glossopharyngeal and vagal sensory ganglia. It is possible that Syn has a function about the immune mechanism of the upper air way.

Delayed tooth movement in Runx2+/- mice associated with mTORC2 in stretch-induced bone formation.

Runt-related transcription factor 2 (Runx2) is an essential transcription factor for osteoblast differentiation, and is activated by mechanical stress to promote osteoblast function. Cleidocranial dysplasia (CCD) is caused by mutations of RUNX2, and CCD patients exhibit malocclusion and often need orthodontic treatment. However, treatment is difficult because of impaired tooth movement, the reason of which has not been clarified. We examined the amount of experimental tooth movement in Runx2+/- mice, the animal model of CCD, and investigated bone formation on the tension side of experimental tooth movement in vivo. Continuous stretch was conducted to bone marrow stromal cells (BMSCs) as an in vitro model of the tension side of tooth movement. Compared to wild-type littermates the Runx2+/- mice exhibited delayed experimental tooth movement, and osteoid formation and osteocalcin (OSC) mRNA expression were impaired in osteoblasts on the tension side of tooth movement. Runx2 heterozygous deficiency delayed stretch-induced increase of DNA content in BMSCs, and also delayed and reduced stretch-induced alkaline phosphatase (ALP) activity, OSC mRNA expression, and calcium content of BMSCs in osteogenic medium. Furthermore Runx2+/- mice exhibited delayed and suppressed expression of mammalian target of rapamycin (mTOR) and rapamycin-insensitive companion of mTOR (Rictor), essential factors of mTORC2, which is regulated by Runx2 to phosphorylate Akt to regulate cell proliferation and differentiation, in osteoblasts on the tension side of tooth movement in vivo and in vitro. Loss of half Runx2 gene dosage inhibited stretch-induced PI3K dependent mTORC2/Akt activity to promote BMSCs proliferation. Furthermore, Runx2+/- BMSCs in osteogenic medium exhibited delayed and suppressed stretch-induced expression of mTOR and Rictor. mTORC2 regulated stretch-elevated Runx2 and ALP mRNA expression in BMSCs in osteogenic medium. We conclude that Runx2+/- mice present a useful model of CCD patients for elucidation of the molecular mechanisms in bone remodeling during tooth movement, and that Runx2 plays a role in stretch-induced proliferation and osteogenesis in BMSCs via mTORC2 activation.

Vibration enhances osteoclastogenesis by inducing RANKL expression via NF-κB signaling in osteocytes.

To shorten the duration of orthodontic treatment it is important not only to reduce risks such as dental caries, periodontal disease, and root resorption, but also to decrease pain and discomfort caused by a fixed appliance. Several studies have investigated the effect of vibration applied to fixed appliances to accelerate tooth movement. Although it was reported that vibration accelerates orthodontic tooth movement by enhancing alveolar bone resorption, the underlying cellular and molecular mechanisms remain unclear. In this study, we investigated the effects of vibration on osteoclastogenesis in vitro and in vivo. Vibration applied to pre-osteoclast cell line RAW264.7 cells enhanced cell proliferation but did not affect their differentiation into osteoclasts. Osteocytes in bone are known to be mechanosensitive and to act as receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL). Therefore, in the present study, vibration was applied to cells from the osteocyte-like cell line MLO-Y4. In MLO-Y4 cells, vibration induced phosphorylation of the inhibitor of NF-κB (IκB) and caused nuclear localization of NF-κB p65. Additionally, vibration increased RANKL mRNA expression, but did not affect osteoprotegerin (OPG) mRNA expression in MLO-Y4 cells, thus resulting in an increased RANKL/OPG ratio. Consistent with these findings, vibration applied during experimental tooth movement increased NF-κB activation and RANKL expression in osteocytes on the compression side of alveolar bone in vivo, whereas vibration had no such effects on the tension side. Furthermore, in a co-culture of MLO-Y4 cells and RAW264.7 cells, vibration applied to MLO-Y4 cells enhanced osteoclastogenesis. These findings suggest that vibration could accelerate orthodontic tooth movement by enhancing osteoclastogenesis through increasing the number of pre-osteoclasts and up-regulating RANKL expression in osteocytes on the compression side of alveolar bone via NF-κB activation.

Biosafety, stability, and osteogenic activity of novel implants made of Zr70Ni16Cu6Al8 bulk metallic glass for biomedical application.

Superior mechanical and chemical properties of Zr70Ni16Cu6Al8 bulk metallic glass (BMG) demonstrate its promise as a novel biomaterial for fabrication of implants. The aim of the present study was to validate mechanical, chemical, and biological properties of Zr70Ni16Cu6Al8 BMG through comparison with titanium (Ti). Our data indicated higher tensile strength, lower Young's modulus, and reduced metal ion release of Zr70Ni16Cu6Al8 BMG compared with Ti. Biosafety of bone marrow mesenchymal cells on Zr70Ni16Cu6Al8 BMG was comparable to that of Ti. Next, screw-type implant prototypes made of Zr70Ni16Cu6Al8 BMG were fabricated and inserted into rat long bones. Zr70Ni16Cu6Al8 BMG implants indicated a higher removal-torque value and lower Periotest value compared with Ti implants. In addition, higher amounts of new bone formation and osseointegration were observed around Zr70Ni16Cu6Al8 BMG implants compared with Ti implants. Moreover, gene expression analysis displayed higher expression of osteoblast- and osteoclast-associated genes in the Zr70Ni16Cu6Al8 BMG group compared with the Ti group. Importantly, loading to implants upregulated bone formation, as well as osteoblast- and osteoclast-associated gene expression in the peri-implant area. No significant difference in concentrations of Ni, Al, Cu, and Zr in various organs was shown between in the Zr70Ni16Cu6Al8 BMG and Ti groups. Collectively, these findings suggest that Zr70Ni16Cu6Al8 BMG is suitable for fabricating novel implants with superior mechanical properties, biocompatibility, stability, and biosafety compared with Ti. STATEMENT OF SIGNIFICANCE: Titanium is widely used to fabricate orthopedic and dental implants. However, Titanium has disadvantages for biomedical applications in regard to strength, elasticity, and biosafety. Recently, we developed a novel hypoeutectic Zr70Ni16Cu6Al8 BMG, which has superior mechanical and chemical properties. However, the validity of Zr70Ni16Cu6Al8 BMG for biomedical application has not been cleared. The aim of the present study was to validate the mechanical, chemical, and biological properties of Zr70Ni16Cu6Al8 BMG for biomedical applications through comparison with Titanium. The present study clarifies that Zr70Ni16Cu6Al8 BMG has good mechanical properties, corrosion resistance, and osteogenic activity, which are necessary features for biomedical applications. The present study provides for the first time the superiority of Zr70Ni16Cu6Al8 BMG implants to Titanium implants for biomedical applications.

Synergistic acceleration of experimental tooth movement by supplementary high-frequency vibration applied with a static force in rats.

Several recent prospective clinical trials have investigated the effect of supplementary vibration applied with fixed appliances in an attempt to accelerate tooth movement and shorten the duration of orthodontic treatment. Among them, some studies reported an increase in the rate of tooth movement, but others did not. This technique is still controversial, and the underlying cellular and molecular mechanisms remain unclear. In the present study, we developed a new vibration device for a tooth movement model in rats, and investigated the efficacy and safety of the device when used with fixed appliances. The most effective level of supplementary vibration to accelerate tooth movement stimulated by a continuous static force was 3 gf at 70 Hz for 3 minutes once a week. Furthermore, at this optimum-magnitude, high-frequency vibration could synergistically enhance osteoclastogenesis and osteoclast function via NF-κB activation, leading to alveolar bone resorption and finally, accelerated tooth movement, but only when a static force was continuously applied to the teeth. These findings contribute to a better understanding of the mechanism by which optimum-magnitude high-frequency vibration accelerates tooth movement, and may lead to novel approaches for the safe and effective treatment of malocclusion.

Gene Expression Analysis of CCN Protein in Bone Under Mechanical Stress.

To investigate mechanical-dependent bone remodeling, we had previously applied various types of mechanical loading onto the teeth of rats and mice. In vitro cultured bone cells were then used to elucidate the mechanisms underlying the specific phenomenon revealed by in vivo experiments. This review describes the techniques used to upregulate CCN2 expression in bone cells produced by different types of mechanical stress, such as fluid shear stress and substrate strain in vitro, and compression or tension force in vivo.

Dynamical behavior and peak power reduction in a pair of energy storage oscillators coupled by delayed power price.

This paper investigates dynamics of a management system for controlling a pair of energy storages. The system involves the following two characteristics: each storage behaves in a manner that reduces the number of charge noncharge cycles and begins to be charged when the price of power is lower than a particular price threshold. The price is proportional to the past total power flow from a power grid to all storages. A peak of the total power flow occurs when these storages are charged simultaneously. From the viewpoint of nonlinear dynamics, the energy storages can be considered as relaxation oscillators coupled by a delay connection. Our analytical results suggest that the peak can be reduced by inducing an antiphase synchronization in coupled oscillators. We confirm these analytical results through numerical simulations. In addition, we numerically investigate the dynamical behavior in 10 storages and find that time delay in the connection is important in reducing the peak.