Search

Summary: Total joint replacement (TJR) of the temporomandibular joint (TMJ) is a promising surgical procedure and device for treating end-stage diseases of the TMJ. For the functional and aesthetic reconstruction of the oral and maxillofacial head and neck region, TMJ TJR significantly helps maintain the patient’s quality of life in terms of a better diet, mastication, speech and social interaction. TMJ TJR was approved by regulatory authorities in 2019 in Japan, thus enabling the clinical application of the TJR system. However, the surgery demands particularly difficult and high-risk procedures, necessitating the prudent selection of indicated patients. The joint committee of the Japanese Society of Oral and Maxillofacial Surgeons and Japanese Society for Temporomandibular Joint is working together to develop an appropriate clinical guideline for TMJ TJR.

Objective Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a disease which exhibits limiting mouth opening caused by hyperplasia of the tendon and aponeurosis of bilateral masticatory muscles. Although it is unclear whether hyperplasticity of tendons in MMTAH is due to cyclic stretch, we hypothesize that cyclic stretch is the main cause of force on MMTAH. In this study, we examined decorin expression in the masticatory muscle tendon of MMTAH patients. We also examined decorin (Dcn) expression of tenocytes on which stretch forces are loaded to explore whether stretch forces affect yes-associated protein (YAP) signaling and whether Dcn expression is regulated by YAP. Methods Quantitative reverse-transcription polymerase chain reaction, immunoblot analysis and immunohistochemistry were performed in tendons of patients having MMTAH. Mechanical loading experiment for TT-D6 tendon fibroblastic cells using RNA interference technique was conducted. Results We found that Dcn expression is increased in tendons of MMTAH patients. We also showed that cyclic stretch force increases decorin expression in TT-D6 tendon fibroblastic cells and that Dcn expression is regulated via YAP in TT-D6 tendon fibroblastic cells acted upon by cyclic stretch. Conclusions Our results, for the first time, demonstrated that cyclic stretch induces decorin expression via YAP in tenocytes and Dcn is upregulated in tendons of MMTAH, suggesting that tendons of MMTAH were subjected to cyclic stretch conditions.

Objective Osteoporosis has become a critical public health problem with the rapidly aging population in Japan. It is necessary for dentists to know their patients' status because it influences dental treatment. The purpose of this study was to predict the risk of osteoporosis in elderly patients visiting a dental clinic by assessing mandibular cortical morphology on panoramic radiographs. Method Three-hundred and thirty patients were divided into three classes based on the morphology of their mandibular cortex on panoramic radiographs. Mandibular cortical bone width at the mental foramen was also measured. Bone mineral density (BMD) was determined at the calcaneus using a quantitative ultrasound device. Results The mandibular cortical width decreased significantly from Class 1 (normal cortex), to Class 2 (moderately eroded cortex) and to Class 3 (severely eroded cortex). BMD was negatively correlated with age in both female and male patients. Most (108/186) female patients had a class 3 cortex with a low BMD. Among women, mandibular cortical width was significantly correlated with BMD. Thirty-three percent of the female had received a previous diagnosis of osteoporosis. In contrast, only 13.9% (20/144) of the male had a Class 3 cortex. In men, mandibular cortical width did not significantly correlate with BMD. Only a few of the men had received a previous diagnosis of osteoporosis. The number of remaining teeth did not correlate with low BMD in either sex. Conclusion Our findings reveal that most elderly female patients visiting the dental clinic had a high risk of osteoporosis and a low BMD.

The aim of the study was to investigate the difference in response to a motor imagery task between individuals with and without painful temporomandibular disorders (TMDs). The participants were 24 adults with and without TMD (TMD and control group, resp.). A set of photographic images of the profile view of a person’s head and neck and a hand and a foot were presented in a random order. The set consisted of six different orientations with rotations of each image at 0, 60, 120, 180, 240, and 300 degrees and included left and right representations. The participants were required to view the image and make a decision as to whether it was a left or a right side presented, that is, mental rotation (MR) task. Data were collected on 48 tasks (including left and right) at each orientation for each body part. Reaction times (RTs) for correct answers and accuracy in making the left or right judgements were recorded. The RT was slower in the TMD group than in the control group. The RT for the profile image was slower than those for the hand and foot images. For images that were 180 degrees, the RT was slower and the accuracy was lower than those for five of the other image orientations. The judgements made about the 180-degree rotated image were more inaccurate compared to images of all other orientations among all types of stimuli.

[Purpose] This study aimed to investigate the characteristics of upper quadrant posture of young women with temporomandibular disorders. [Subjects] The participants were 19 female patients with temporomandibular disorders (patient group: mean age, 30.1 years) and 14 controls (control group: mean age, 24.6 years). [Methods] Outcome measures were the neck inclination angle (formed by a line connecting C7 and the ear tragus with a horizontal line), the angle of the shoulder (formed by a line connecting C7 and the acromial angle with a horizontal line), the cranial rotation angle (formed by a line connecting the ear tragus and the corner of the eye with a horizontal line), and the neck-length/shoulder-width ratio [the ratio of the neck length (from C7 to the tragus) to the width of the shoulder between the acromial angle]. The maximum range of mouth opening was measured using a scale. [Results] The neck inclination angle and maximum range of mouth opening were significantly smaller in the patient group than in the control group. No significant differences were observed in the other outcome measures between the two groups. [Conclusion] Temporomandibular disorders with limited mouth opening in young females are associated with the head position relative to the trunk.

Staphylococcal exfoliative toxins are involved in some cutaneous infections in mammals by targeting desmoglein 1 (Dsg1), a desmosomal cell-cell adhesion molecule. Recently, an exfoliative toxin gene (exi) was identified in Staphylococcus pseudintermedius isolated from canine pyoderma. The aim of this study was to identify novel exfoliative toxin genes in S. pseudintermedius. Here, we describe a novel orf in the genome of S. pseudintermedius isolated from canine impetigo, whose deduced amino acid sequence was homologous to that of the SHETB exfoliative toxin from Staphylococcus hyicus (70.4%). The ORF recombinant protein caused skin exfoliation and abolished cell surface staining of Dsg1 in canine skin. Moreover, the ORF protein degraded the recombinant extracellular domains of canine Dsg1, but not Dsg3, in vitro. PCR analysis revealed that the orf was present in 23.2% (23/99) of S. pseudintermedius isolates from dogs with superficial pyoderma exhibiting various clinical phenotypes, while the occurrence in S. pseudintermedius isolates from healthy dogs was 6.1% (3/49). In summary, this newly found orf in S. pseudintermedius encodes a novel exfoliative toxin, which targets a cell-cell adhesion molecule in canine epidermis and might be involved in a broad spectrum of canine pyoderma.

Temporomandibular joint disorders (TMD) show complex symptoms associated with inflammation, pain and degeneration of the peripheral tissues including synovium. Although it is believed that excessive mechanical stress on synovium causes development of TMD, the molecular mechanism by which mechanical stress triggers TMD has still remained unclear. In order to examine the effect of mechanical stress on synoviocytes, rabbit synovial cells were cyclically stretched in vitro. The stretch efficiently increased the gene expressions of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) and NF-kappaB responsive reporter gene constructs. The interruption of NF-kappaB activating pathway by inhibitors resulted in the abrogation of those expressions, indicating the pivotal role of NF-kappaB in the mechanical stretch-mediated COX-2 and iNOS expressions. In parallel, the stretch remarkably increased NO production and poly(ADP-ribose) (PAR) synthesis, suggesting that excessive amounts of NO causes DNA injury and in turn activates PAR synthesis by poly(ADP-ribose) polymerase (PARP). The inhibition of PAR synthesis by a PARP inhibitor or a radical scavenger enhanced the mechanical stretch-induced gene expressions in a NF-kappaB-independent manner, implying an involvement of PARP in the gene expression. Taken together, these results demonstrate that mechanical stress on synovial cells not only induces gene expressions of COX-2 and iNOS but also affects PAR synthesis.

To understand species distribution, trends of antimicrobial susceptibility and prevalence of methicillin resistance in canine staphylococci in Japan, 190 coagulase-positive staphylococci (CoPS) were isolated from dogs with pyoderma in 2 Japanese veterinary referral hospitals. Using a multiplex polymerase chain reaction (M-PCR) method, two CoPS species were identified: 170 Staphylococcus pseudintermedius (89.5%) and 20 S. schleiferi subsp. coagulans isolates (10.5%). In these isolates, susceptibility to 7 antimicrobial agents was determined. Overall, the levels of susceptibility to cefalexin (CEX), amoxicillin/clavulanic acid (CVA/AMPC), minocycline (MINO), ofloxacin (OFLX), norfloxacin (NFLX), lincomycin (LCM) and clindamycin (CLDM) in S. pseudintermedius isolates were 38.2, 52.4, 34.7, 31.2, 34.1, 1.2 and 11.2%, respectively. In S. schleiferi subsp. coagulans isolates, 55% demonstrated susceptibility to CEX, 80% to CVA/AMPC, 70% to MINO, 45% to OFLX or NFLX and 30% to CLDM. None of S. schleiferi subsp. coagulans isolates was susceptible to LCM. To determine the prevalence of methicillin-resistant strains, we used a PCR method, which enabled detection of the fragment of mecA gene in 66.5% (113 of 170) in S. pseudintermedius and 30.0% (6 of 20) in S. schleiferi subsp. coagulans isolates. The frequencies of susceptibility to CEX, CVA/AMPC, OFLX, NFLX and CLDM were significantly lower in methicillin-resistant CoPS than in methicillin-susceptible CoPS isolates. These data suggest a high level of methicillin resistance in staphylococci isolated from dogs with pyoderma in Japan.

The cyclopentenonic prostaglandin 15-deoxy-Delta(12,14)-PG J(2) (15d-PGJ(2)) is a metabolite derived from PGD(2). Although 15d-PGJ(2) has been demonstrated to be a potent ligand for peroxisome proliferator activated receptor gamma (PPARgamma), the functions are not fully understood. In order to examine the effect of 15d-PGJ(2) on histone acetyltransferases (HATs), several lines of cell including mouse embryonic fibroblast (MEF) cells were exposed to 15d-PGJ(2). Three types of HAT, p300, CREB-binding protein (CBP), and p300/CBP-associated factor (PCAF), selectively disappeared from the soluble fraction in time- and dose-dependent manners. Inversely, HATs in the insoluble fraction increased, suggesting their conformational changes. The decrease in the soluble form of HATs resulted in the attenuation of NF-kappaB-, p53-, and heat shock factor-dependent reporter gene expressions, implying that the insoluble HATs are inactive. The resultant insoluble PCAF and p300 seemed to be digested by proteasome, because proteasome inhibitors caused the accumulation of insoluble HATs. Taken together, these results indicate that 15d-PGJ(2) attenuates some gene expressions that require HATs. This inhibitory action of 15d-PGJ(2) on the function of HATs was independent of PPARgamma, because PPARgamma agonists could not mimick 15d-PGJ(2) and PPARgamma antagonists did not inhibit 15d-PGJ(2).

This report is of a 44-year-old man with osteochondroma of the mandibular condyle. Condylectomy and immediate reconstruction with autogenous costochondral graft resulted in a good long-term outcome.

Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a new disease entity characterized by limited mouth opening due to contracture of the masticatory muscles, resulting from hyperplasia of tendons and aponeuroses. In this case series, we report what methods of airway establishment were conclusively chosen after rapid induction of anesthesia. We had 24 consecutive patients with MMTAH who underwent surgical release of its contracture under general anesthesia. Rapid induction of anesthesia with propofol and rocuronium was chosen for all the cases. In 7 cases, intubation using the Macintosh laryngoscopy was attempted; however, 2 of those cases failed to be intubated on the first attempt. Finally, intubation using the McCoy laryngoscopy or fiber-optic intubation was alternatively used in these 2 cases. In 7 cases, the Trachlight was used. In the remaining 10 cases, fiber-optic intubation was used. Limited mouth opening in patients with MMTAH did not improve with muscular relaxation. “Square mandible” has been reported to be one of the clinical features in this disease; however, half of these 24 patients lacked this characteristic, which might affect a definitive diagnosis of this disease for anesthesiologists. An airway problem in patients with MMTAH should not be underestimated, which means that other intubation methods rather than direct laryngoscopy had better be considered.

Willis'circle occlusion refers to stenosis or occlusion of the internal carotid artery arising from Willis'circle, associated with visible capillaries comprising the collateral circulation.The patient was a 27-year-old woman who had previously undergone duraencephalosynangiosis at 17 years of age and extracranial-intracranial bypass surgery at 23 years of age. She was examined at the Department of Oral and Maxillofacial Surgery, Nara Medical University Hospital on January 12, 2000 because of temporomandibular joint (TMJ) pain and limited mouth opening. At presentation, maximum mouth opening was 17mm. We describe the successful treatment of severe pain of the left TMJ and trismus by mobilization of the TMJ.The pain caused hyperventilation, cataplexy, and numbness of the hands and feet. Angiography showed that blood flow had improved after the extracranial-intracranial bypass. Conservative treatment was unsuccessful. On March 3, 2000, mobilization of the TMJ was done under general anesthesia. The superficial temporal artery was exposed, and blood flow was managed with by microdoppler technique.Postoperatively, the patient's pain resolved, and maximum mouth opening increased significantly from 17mm to 38mm. Forward movement and lateral movement increased to 8mm.The improvement on a visual analogue scale was also significant. No complications have occurred. As of 15 months after the operation, the response of Willis' circle occlusion to treatment has been good.

We describe a unique patient with mosquito-bite hypersensitivity who had extremely high titres of Epstein-Barr virus antibodies. For many years he developed intractable ulcers on the sites of mosquito-bite. Epstein-Barr virus infection was detected in almost all inflammatory cells in the ulcers and in the peripheral blood lymphocytes by using in situ hybridization to Epstein-Barr virus-encoded small ribonucleic acids and by polymerase chain reaction to Epstein-Barr virus DNA. The inflammatory cells in the ulcers were positive for T-cell marker. Our results suggest that the Epstein-Barr virus infection in T cells may participate in the pathogenesis of exaggerated mosquito hypersensitivity and in delayed healing of ulcers on the sites of mosquito-bite.

It has been reported that loading to the mandible during closing movement makes the condylar path move more in the superior direction than that during the free closing movement. In this study, the hypothesis was tested that the displacement of the condyle on the chewing side is greater in the direction of the mandibular fossa than that on the non-chewing side. Using a six-degrees-of-freedom jaw movement recording system, we recorded condylar motion in 12 healthy adults without TMD, during the chewing of a large hard gummy jelly. The maximum displacements at the condyle on the chewing side from the maximum intercuspation (CO) position were significantly larger in the superior and medial directions at the initial stage and in the posterior direction at all stages (0.5 mm, 0.5 mm, and 0.6 mm, respectively) than those on the non-chewing side (0.0 mm, 0.1 mm, and 0.1 mm, respectively). This suggests that, in healthy adults, the condyles at CO are located in a position such that excessive load is not applied to the temporomandibular joint when there are the aforementioned displacements.

Osteochondromas are outgrowths from the epiphyseal regions of bones, particularly the lower end of the femur and upper end of the tibia. In the jaws, solitary growths occur in the coronoid process of the mandible and in the mandibular condyle.An unusual case of osteochondroma of the mandibular fossa is reported. The patient was a 63-year-old man with recurrent luxation of the temporomandibular joint who had malocclusion, but symmetry of the mandible. A radiographic examination showed a well-circumscribed ovoid radiopacity in the left temporomandibular joint space. Computed and three-dimensional tomographic scans showed a loose body between the left mandibular fossa and the condylar head. On MR imaging, the loose body was found to be chondroid tissue, and the disk was dislocated anteriorly.Histological examination revealed a cartilage-capped overgrowth with cartilageous ossification, which had apparently arose in the left mandibular fossa.The patient was followed up for 1 year 3 months. There was no tumor recurrence or temporomandibular joint disorder.

We demonstrated in our previous paper [Appl. Phys. Lett. 74, 275 (1999)] that TaTi contacts annealed at temperature of 800 °C provided a specific contact resistance (ρc) of around 3×10−5 Ω cm2 for p-GaN epilayers with hole concentration of 7.0×1017 cm−3. The reduction of the contact resistances was believed to be due to reactivation of Mg atoms doped in the GaN epilayer by removing H. In the present article, diffusion behavior of hydrogen atoms in the p-GaN was extensively studied by secondary-ion mass spectroscopy and correlated with the electrical properties of the TaTi contacts. It was found that formation of the low-resistance TaTi ohmic contacts was well explained by diffusion behavior of hydrogen in the p-GaN. Although the deterioration rates of the TaTi contacts during low temperature storage after ohmic contact formation were coincident with the diffusion rates of hydrogen atoms in the GaN, the deterioration mechanism could not be explained simply by hydrogen release from the TaTi contacts into th...

We clinically studied 30 patients (34 joints) with closed lock who underwent arthroscopic surgery (lysis and lavage operations) of the superior joint compartment of the temporomandibular joint (TMJ). Arthroscopic surgery was studied as compared with arthrocenthesis and pumping manipulation by double-contrast arthrotomography and magnetic resonance imaging (MRI).The results were as follows:1. There was arthrographic evidence of marked narrowing of the anterior recess and lateral portion, of the upper joint compartment in patients who underwent arthrocenthesis and pumping, whereas narrowing of the posterior compartment and medial portion was found in patients who underwent arthroscopic surgery.2. In patients who underwent arthrocenthesis, MRI showed that anterior disk displacement and disk deformity were severer than after arthroscopic surgery.3. There was arthroscopic evidence of extensive synovitis, and osteoarthrosis and adhesionwere severe in the anterior recess.We found that upper joint arthroscopy of the TMJ was an important additional diagnostic method and that arthroscopy was effective in the diagnosis of synovitis and osteoarthrosis within the superior cavity and permitted the observation of adhesion.

To examine the existence of PRL messenger ribonucleic acid (mRNA) in the mouse placenta during late pregnancy, reverse transcriptase-polymerase chain reaction (RT-PCR) and Southern blot analysis were carried out followed by nucleotide sequence analysis of cDNA. Total RNA extracted from each tissue was reverse-transcribed, followed by PCR with two oligonucleotide primers specific for a part of mouse PRL (mPRL) cDNA. An amplified RT-PCR product of predicted size was detected in all samples from the placenta of days 16 and 18 pregnant mice. This product was specifically hybridized with a probe overlapping an entire sequence of mPRL cDNA in Southern blot analysis. Nucleotide sequence analysis also provided evidence that the amplified cDNA had a nucleotide sequence completely identical to the mPRL cDNA sequence reported previously. Furthermore, mPRL with a slightly bigger molecular weight than that of pituitary PRL was detected in the placenta of days 12, 14, 16 and 18 pregnancy by immunoblot analysis. These results suggest that PRL mRNA and its translation product are synthesized in mouse placenta during late pregnancy.

A ligand of peroxisome proliferator-activated receptor γ (PPARγ), 15-deoxy-Δ(12,14)-prostaglandin J2 (15d-PGJ2) induces apoptosis in various cells. However, the mechanism appears to be complex and cell-type specific. We investigated the mechanism of 15d-PGJ2-induced apoptosis of rabbit synovial cells. Exposure to 15d-PGJ2 resulted in DNA fragmentation accompanied by caspase-3 and -9 activations in the cells, suggesting occurrence of mitochondria-mediated apoptosis. Although the exposure also induced remarkable increase in p53 protein, its transcriptional activity was rather reduced, suggesting non-necessity of p53 in 15d-PGJ2-induced apoptosis. Covalent binding of 15d-PGJ2 to cellular proteins including p53 resulted in their insolubilization. N-acetylcysteine inhibited not only the 15d-PGJ2-induced apoptotic events but also the protein insolubilizations via its interaction with 15d-PGJ2. The studies using a PPARγ-agonist and -antagonist showed noninvolvement of PPARγ in 15d-PGJ2-induced apoptosis. The pre-exposure to pro-inflammatory cytokines did not affect the cytotoxicity of 15d-PGJ2 in synovial cells. Taken together, these results show that 15d-PGJ2 induces a mitochondria-mediated apoptotic pathway in p53- and PPARγ-independent manners.

In systematic research on a series of new nonlinear organic materials, we found that Bis (4-nitrophenoxy) methane (BNPM) showed a large intensity of second harmonic light, which was 4.4 times as large as that of urea crystal by powder technique and easily crystallized from a solution. The crystal structure of BNPM, obtained by the X-ray diffraction method, was orthorhombic, space group P21212 (point group 222), with unit-sell dimension a = 10.205 A; b = 12.854 A; c = 4.8822 A. In addition, we found that the absorption edge of BNPM was 430 nm with a 0.9-mm-thick crystal, and we observed the second harmonic light with BNPM single crystal at the wavelength of 1064 nm and in the range from 906 nm to 990 nm.

A postoperative follow-up study of internal derangement with persistent closed lock after arthroscopic surgery of the temporomandibular joint was performed in 9 patients, 11 joints.Using a triangulation technique via a second puncture, diagnostic arthroscopy was performed, followed by arthroscopic lysis and lavage operation of the temporomandibular joint to increase mobility of condyle-disk complex. This was accomplished by using power instrumentation (Microdebrider-Small Joint Microelectric Arthroplasty System) in conjunction with an irrigation system.We evaluated the efficiency of this instrument and irrigation system for temporomandibular joint arthroscopic surgery.According to the criteria of the American Society of Oral and Maxillofacial Surgery and those of Takahashi and Shibata, the surgical success rate was 88.9%. Postoperatively, there was no complication or severe discomfort.

Staphylococcal exfoliative toxins are involved in some cutaneous infections in mammals by targeting desmoglein 1 (Dsg1), a desmosomal cell-cell adhesion molecule. Recently, an exfoliative toxin gene (exi) was identified in Staphylococcus pseudintermedius isolated from canine pyoderma. The aim of this study was to identify novel exfoliative toxin genes in S. pseudintermedius. Here, we describe a novel orf in the genome of S. pseudintermedius isolated from canine impetigo, whose deduced amino acid sequence was homologous to that of the SHETB exfoliative toxin from Staphylococcus hyicus (70.4%). The ORF recombinant protein caused skin exfoliation and abolished cell surface staining of Dsg1 in canine skin. Moreover, the ORF protein degraded the recombinant extracellular domains of canine Dsg1, but not Dsg3, in vitro. PCR analysis revealed that the orf was present in 23.2% (23/99) of S. pseudintermedius isolates from dogs with superficial pyoderma exhibiting various clinical phenotypes, while the occurrence in S. pseudintermedius isolates from healthy dogs was 6.1% (3/49). In summary, this newly found orf in S. pseudintermedius encodes a novel exfoliative toxin, which targets a cell-cell adhesion molecule in canine epidermis and might be involved in a broad spectrum of canine pyoderma.

In veterinary medicine, coagulase-positive staphylococci (CoPS) other than Staphylococcus aureus have frequently been misidentified as being S. aureus strains, as they have several phenotypic traits in common. There has been no reliable method to distinguish among CoPS species in veterinary clinical laboratories. In the present study, we sequenced the thermonuclease ( nuc ) genes of staphylococcal species and devised a multiplex-PCR (M-PCR) method for species identification of CoPS by targeting the nuc gene locus. To evaluate sensitivity and specificity, we used this M-PCR method on 374 staphylococcal strains that had been previously identified to the species level by an hsp60 sequencing approach. We could successfully distinguish between S. aureus , S. hyicus , S. schleiferi , S. intermedius , S. pseudintermedius , and S. delphini groups A and B. The present method was both sensitive (99.8%) and specific (100%). Our M-PCR assay will allow the routine species identification of CoPS isolates from various animal species for clinical veterinary diagnosis.

Chemokines are important regulators of the selective recruitment of inflammatory cells into sites of allergic inflammation. Since canine atopic dermatitis (AD) shares many clinical features of human AD, patterns of chemokine production in dogs may also be similar with those in humans. The aim of this study was to examine mRNA expression of CCL27 and CCL28 in lesional skin of dogs with AD to demonstrate similarity of chemokine production with human counterparts. RNA was extracted from skin biopsy specimens of 12 dogs with AD. The mRNA expression of CC chemokines (CCL4, CCL19, CCL20, CCL21, CCL24, CCL27 and CCL28) was analyzed by quantitative real-time PCR and was compared between lesional and non-lesional skin. Seven types of chemokines examined were constitutively expressed in both lesional and non-lesional skin. It was found that mRNA expression levels of CCL27 and CCL28 among the chemokines were significantly different between lesional and non-lesional skin (P

Although extensive efforts have continued to develop Ohmic contacts for p-type GaN, which have specific contact resistance (ρc) lower than that (ρc∼10−2 Ω cm2) of conventional Ni/Au contacts, to the best of our knowledge no breakthrough has been reported in open literature. We demonstrated that bilayered Ta/Ti contacts have a ρc value of around 3×10−5 Ω cm2 for p-type GaN with a hole concentration of 7×1017 cm−3. This contact has resistance low enough to manufacture blue laser diodes, but deterioration of the ρc value during room-temperature storage is the key issue.

Recent studies on temporomandibular joint (TMJ) disorders have suggested that matrix metalloproteinases (MMPs) are closely involved in the pathophysiological progression of the internal derangement (ID) of TMJ. The aim of this study was to investigate MMPs in synovial fluid (SF) at different stages of ID. To examine the relationship between MMP activation and ID progression, 54 SF samples from ID patients were classified based on the criteria of Wilkes and were assayed for MMP activity. It was found that MMP-3 activity was transiently increased in the intermediate stage. This increase in the active form of MMP-3 was also confirmed by Western blotting. When the 54 samples were classified into two groups based on the presence or absence of inflammatory findings, the intensity of MMP-3 activity correlated with the inflammatory symptoms. These findings suggest that MMP-3 activation is a hallmark of early degenerative changes in ID. The tylosin nitration by the peroxynitrite can regulate the enzyme activity. To elucidate the activating pathway of MMPs in vivo, nitrated proteins in SF were analysed by immunoprecipitation. Some nitrated proteins in SF were identified as MMP-2 and -3, and the nitration of MMP-3 rendered them active in vitro.

Structured Abstract Authors – Kawakami M, Yamamoto K, Inoue M, Kawakami T, Fujimoto M, Kirita T Objective – To investigate the morphology of the temporomandibular joints (TMJ) in skeletal asymmetry with prognathism. Design – Three-group observational clinical study. Setting and Sample Population – University setting. Thirty-five patients undergoing orthognathic surgery without signs and symptoms of TMJ disorder were assigned to three groups (right deviation, n = 11; left deviation, n = 14; and non-deviation; n = 10) based on anteroposterior cephalometric analysis. Outcome Measure – Positional and morphological differences of the TMJs were evaluated using a total of 70 bilateral sagittal TMJ magnetic resonance images. Results – In both the right and left deviation groups, the TMJ on the deviated side showed a significantly steeper eminence than that on the non-deviated side (p

In this paper, three cases of acute suppurative arthritis of the temporomandibular joint, occurring in a 65-year-old man (case 1), 40-year-old woman (case 2), and 67-year-old woman (case 3), are presented.Clinical signs and symptoms were general malaise, pyrexia, trismus with localized swelling, tenderness, waviness over the left temporomandibular joint, and malocclusion with deviation of the mandible to the healthy side.

Open surgery for internal derangement of the temporomandibular joint was performed in 9 patients, 10 joints. Postoperative follow-up studies of 17 months or more are described.Satisfactory results were obtained in 8 cases, 9 joints according to the criteria of the American Society of Oral and Maxillofacial Surgery in 8 cases, 8 joints according to the criteria of Takahashi and Shibata. No surgical complication or postoperative severe discomfort was encountered. The surgical success rate was 88.9%.

The purpose of this study was to investigate the changes in masticatory muscle activity according to food size in human mastication. Sixteen subjects performed deliberate unilateral chewing of similarly cone shaped hard gummy jellies weighing 5 and 10 g. The masseter and anterior temporal muscle activity on both sides was recorded for the first 10 strokes. The normalized muscle activity during the chewing of the 10 g jelly was significantly higher than that of the 5-g jelly, and there was a considerably high significant correlationship between the muscle activity during the chewing of the 10- and 5-g jellies in each muscle on each side. The 10 g/5 g jelly ratio for the masseter muscle activity on the non-chewing side almost coincided with the theoretical energy ratio required to shear, although that of the chewing side was lower than the ratio. The 10 g/5 g jelly ratio for the temporal muscle activity on both sides almost coincided with the food height ratio. The results suggest that anterior temporal and masseter muscle activity changes according to the rate of change in the height of hard coherent food bolus and food resistance required to shear, respectively, during mastication.

A total of 74 specimens was obtained from the normal human skin of patients from 3 to 90 years old. The specimens were roughly classified into 5 groups: 15 for the face group from the face; 15 for the abdomen group from the abdomen; 13 for the back group from the back; 14 for the arm group from the upper arm and forearm; and 17 for the leg group from the thigh and lower leg. They were all fixed in 4% paraformaldehyde and 14% saturated picric acid. Cryostat sections were examined by the immunoperoxidase method and indirect immunofluorescence (IF). Primary antibodies against neurofilament, neuron-specific enolase, protein gene product 9.5 (PGP 9.5) and S-100 protein were used. The most effective method was found to be the combination of IF with PGP 9.5; it visualized the intraepidermal nerve fibers easily and clearly. Of the 74 specimens, 32 (43%) had intraepidermal PGP 9.5-immunoreactive (or nerve) fibers (IPIF), and 42 (57%) did not have any. With reference to the different skin locations, the maximal rate of specimens having IPIF was 57% in the arm group, and the minimum was 23% in the back group. IPIF positive specimens had approximate surface lengths of 6 mm, in which the existence number of the IPIF was 1 to 75. Their distribution density per 1000 epidermal basal cells was highest at 9.63 in the arm group and lowest at 2.89 in the back group. Their thickness was 2.94 +/- 0.83 microns with no significant differences among the five groups. We concluded that intraepidermal nerve fibers may not be distributed evenly in the hairy portions of normal human skin, but they may be present focally. Physiologically, two-point discrimination of itch may be explained by the distribution mode of intraepidermal nerve fibers.

Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a new disease entity characterized by limited mouth opening due to contracture of the masticatory muscles resulting from hyperplasia of tendons and aponeuroses. The other clinical feature is that the face of the patient with this disease displays a square mandible configuration. Muscle relaxants provide no relief for the limited mouth-opening ability. Anesthesiologists need to suspect difficult airway when patients have limited mouth opening with square mandible configuration. MMTAH can therefore be a possible cause of difficult intubation.

To date, the effect of food size on the movement of the mandibular first molars and condyles during chewing has not been fully examined due to methodological problems. The purpose of the present study was to examine the previously unknown effect of food size on masticatory jaw movement. Using a face bow, light-emitting diodes, and optical cameras, we recorded, in 16 young adults with good occlusion, mandibular movement for the first 10 strokes during the unilateral chewing of similarly shaped hard gummy jellies weighing 5 g and 10 g, respectively. The chewing cycle time for the 10-g jelly was significantly longer than that for the 5-g jelly. The jaw-closing and -opening maximum velocities, gapes at the maximum velocities, and maximum gape were significantly faster and larger when 10-g gummy jellies were chewed, compared with results with 5-g jellies, at the mandibular first molar on the chewing side and the condyle on the non-chewing side. With the exception of the velocity, similar tendencies were observed at the molar on the non-chewing side. However, such significant differences were not detected at the condyle on the chewing side. The mandibular first molar on the chewing side was that most affected by food size, and the mean value of the maximum gape coincided approximately with the height of each jelly. These results suggest that humans chew hard coherent food such that the mandibular teeth that come into contact with the food open to a height equivalent to that of the food bolus, and that the changes in movement of the other parts of the mandible are minimized, ensuring efficient mastication.