Molecular imaging in masseter muscle observed by muscle function magnetic resonance imaging and P-magnetic resonance spectroscopy in patients with a jaw deformity.

Background: Skeletal mandibular protrusion would influence to the muscle fatigue of the masticatory muscles. Establishing a diagnostic procedures combining physiological and biochemical information is necessary for quantitative evaluation of masticatory muscle fatigue.

Objective: The transverse relaxation time (T2 time) of muscle functional magnetic resonance imaging (mfMRI), and P-magnetic resonance spectroscopy (MRS) were used to investigate the reliability as parameters for measuring the masseter muscle in patients with skeletal mandibular prognathism.

Development of flash cards to teach about lesions in the jaws and maxillary sinuses.

Objective: We sought to evaluate a set of flash cards to teach about lesions of the jaws and maxillary sinuses.

Methods: We placed illustrations of 30 diseases of the jaws and maxillary sinuses on the front of the cards (7 cm × 5 cm). On the backs of the cards, a description of the radiological findings and the corresponding QR code for each disease were printed.

Effect of exposure parameters and gutta-percha cone size on fracture-like artifacts in endodontically treated teeth on cone-beam computed tomography images.

Objectives: To ascertain the effects of exposure parameters (tube current and tube voltage) and the gutta-percha cone (GPC) size on root fracture-like artifacts obtained with cone-beam computed tomography (CBCT).

Methods: Fracture-like artifacts appearing on CBCT images of nine extracted human mandibular premolars filled with GPCs of size #50 or #80 were analyzed using six exposure factors: two tube voltages (80 kV and 110 kV); and three tube currents (4 mA, 7 mA, and 10 mA). On axial images, the gray value (GV) was recorded at three points: the mesiobuccal portion (MBP) as the sound dentin, the mesial portion (MP) as the artifact line, and the water area (WA).

Identification of a Novel Alternatively Spliced Form of Inflammatory Regulator SWAP-70-Like Adapter of T Cells.

Activation of naive CD4 T cells results in the development of several distinct subsets of effector Th cells, including Th2 cells that play a pivotal role in allergic inflammation and helminthic infections. SWAP-70-like adapter of T cells (SLAT), also known as Def6 or IBP, is a guanine nucleotide exchange factor for small GTPases, which regulates CD4 T cell inflammatory responses by controlling Ca/NFAT signaling. In this study, we have identified a novel alternatively spliced isoform of SLAT, named SLAT2, which lacks the region encoded by exons 2-7 of the gene.

Vascularity as assessed by Doppler intraoral ultrasound around the invasion front of tongue cancer is a predictor of pathological grade of malignancy and cervical lymph node metastasis.

Objectives: To quantitatively evaluate the relationship of vascularity of tongue cancer as demonstrated on intraoral ultrasonography images and tumour thickness with pathological grade of malignancy and the presence of cervical lymph node metastases.

Methods: 18 patients with tongue cancer were enrolled in this retrospective study. Using Doppler ultrasonography images of the invasion front of the cancers along the length of their tumour boundaries, three vascular indexes were analysed quantitatively, namely ratio of blood flow signal area within the cancer to whole tumour area (BAR), blood flow signal number ratio (BNR) and blood flow signal width ratio (BWR).

Interaction between fibronectin and β1 integrin is essential for tooth development.

The dental epithelium and extracellular matrix interact to ensure that cell growth and differentiation lead to the formation of teeth of appropriate size and quality. To determine the role of fibronectin in differentiation of the dental epithelium and tooth formation, we analyzed its expression in developing incisors. Fibronectin mRNA was expressed during the presecretory stage in developing dental epithelium, decreased in the secretory and early maturation stages, and then reappeared during the late maturation stage.

Serum level of soluble (pro)renin receptor is modulated in chronic kidney disease.

Background: Prorenin, the precursor of renin, binds to the (pro)renin receptor [(P)RR] and triggers intracellular signaling. The ligand binding sites of (P)RR are disconnected and are present in the soluble form of the receptor in serum. Given that the clinical significance of serum prorenin and soluble (P)RR in chronic kidney disease (CKD) is unclear, we investigated the relationship between serum prorenin, soluble (P)RR, and various clinical parameters in patients with CKD.

Multiple congenitally missing teeth treated with autotransplantation and orthodontics.

Treatment of children with several congenitally missing teeth is challenging, because growth and development of the oral structures must be considered. The treatment options include retaining the deciduous teeth and postponing treatment until later or extracting the deciduous teeth and doing one of the following: allowing the space to close spontaneously, closing the space orthodontically, or in patients whose growth is finished, using a prosthetic or implant replacement. One other viable option, if donor teeth are available, is autotransplantation.

Serum levels of soluble secreted α-Klotho are decreased in the early stages of chronic kidney disease, making it a probable novel biomarker for early diagnosis.

Background: α-Klotho was first identified as an aging gene and was later shown to be a regulator of phosphate metabolism. Fibroblast growth factor 23 (FGF23) is the key regulator of phosphate metabolism. Serum levels of soluble α-Klotho in chronic kidney disease (CKD) patients have not previously been determined, especially in relation with FGF23 and creatinine levels.

Evaluation of diffusion parameters and T2 values of the masseter muscle during jaw opening, clenching, and rest.

Background: Diffusion-weighted imaging (DWI) and diffusion-tensor imaging (DTI) can be used to evaluate changes that accompany skeletal muscle contraction.

Purpose: To investigate whether jaw opening or closure affect the diffusion parameters of the masseter muscles (MMs).

Material And Methods: Eleven healthy volunteers were evaluated.

Assessment of the sequential change of the masseter muscle by clenching: a quantitative analysis of T1, T2, and the signal intensity of the balanced steady-state free precession.

Background: The persistent muscle contractions during clenching are thought to cause some temporomandibular disorders. However, no report has so far evaluated the effect of clenching on the masticatory muscles by magnetic resonance imaging (MRI).

Purpose: To investigate the effect of clenching with maximum voluntary contraction on the T(1), T(2), and signal intensity (SI) of the balanced fast field-echo (b FFE) of the masseter muscle.

Cervical lymph nodes with or without metastases from oral squamous carcinoma: a correlation of MRI findings and histopathologic architecture.

Objectives: The aim of this study was to describe the magnetic resonance images (MRIs) of the architecture of metastatic lymph nodes as well as healthy lymph nodes and to correlate the images with the histopathologic architecture of the lymph nodes from oral squamous cell carcinoma.

Study Design: The signal intensities of 98 cervical lymph nodes from 20 patients with oral squamous cell carcinoma were evaluated on T2-weighted and diffusion-weighted whole-body imaging with background body signal suppression (DWIBS). The MRI findings were compared with the histopathologic architecture.

Assessment of the relationship between impacted mandibular third molars and inferior alveolar nerve with dental 3-dimensional computed tomography.

Purpose: The purpose of this study was to assess the capacity of dental 3-dimensional computed tomography (3D-CT; limited cone-beam CT) to predict the exposure and injury of the inferior alveolar nerve (IAN) after mandibular third molar extractions.

Materials And Methods: This study was a retrospective case series of patients who presented for extraction of mandibular third molars. Subjects eligible for study enrollment were those who underwent preoperative dental 3D-CT because the mandibular third molars were determined to be extremely close to the IAN on panoramic radiogram.

Influences of interferon-gamma on cell proliferation and interleukin-6 production in Down syndrome derived fibroblasts.

Objective: Down syndrome, a frequently encountered genetic disorder, is usually associated with medical problems related to infectious disease, such as periodontal diseases and prolonged wound healing. Although affected individuals are considered to have clinical problems related to high interferon (IFN) sensitivity, the molecular mechanisms of IFN activities are not completely understood.

Design: Down syndrome derived fibroblasts, Detroit 539 (D1) and Hs 52.

Platelet-derived growth factor receptor regulates salivary gland morphogenesis via fibroblast growth factor expression.

A coordinated reciprocal interaction between epithelium and mesenchyme is involved in salivary gland morphogenesis. The submandibular glands (SMGs) of Wnt1-Cre/R26R mice have been shown positive for mesenchyme, whereas the epithelium is beta-galactosidase-negative, indicating that most mesenchymal cells are derived from cranial neural crest cells. Platelet-derived growth factor (PDGF) receptor alpha is one of the markers of neural crest-derived cells.

Neurotrophic factor neurotrophin-4 regulates ameloblastin expression via full-length TrkB.

Neurotrophic factors play an important role in the development and maintenance of not only neural but also nonneural tissues. Several neurotrophic factors are expressed in dental tissues, but their role in tooth development is not clear. Here, we report that neurotrophic factor neurotrophin (NT)-4 promotes differentiation of dental epithelial cells and enhances the expression of enamel matrix genes.

Amelogenin is a negative regulator of osteoclastogenesis via downregulation of RANKL, M-CSF and fibronectin expression in osteoblasts.

Amelogenin is a novel enamel matrix protein. Knockout mice showed enhanced osteoclast formation and resorption of tooth cementum. This study investigated the effects of amelogenin on osteoclastogenesis.

Current topics in pharmacological research on bone metabolism: osteoclast differentiation regulated by glycosphingolipids.

Glycosphingolipids are thought to play important roles in the development and function of several tissues, although the function of glycolipids in osteoclastogenesis has not been clearly demonstrated. In the present study, D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP), a glucosylceramide synthase inhibitor, completely inhibited osteoclastogenesis induced by macrophage-colony stimulating factor (M-CSF) and receptor activator of NF-kappaB ligand (RANKL). Following treatment with D-PDMP, nearly all glycosphingolipid expression was dramatically reduced on the surface of bone marrow cells, which suggests that glycosphingolipids are necessary for osteoclastogenesis.

Laminin alpha5 is required for dental epithelium growth and polarity and the development of tooth bud and shape.

In tooth development, the oral ectoderm and mesenchyme coordinately and reciprocally interact through the basement membrane for their growth and differentiation to form the proper shape and size of the tooth. Laminin alpha5 subunit-containing laminin-10/11 (LM-511/521) is the major laminin in the tooth germ basement membrane. Here, we have examined the role of laminin alpha5 (Lama5) in tooth development using laminin alpha5-null mouse primary dental epithelium and tooth germ organ cultures.

Intraoral sonographic features of tongue cancer after radical radiotherapy.

Purpose: The purpose was to illustrate the sonographic changes of tongue cancer after radical radiotherapy.

Materials And Methods: In 24 patients with tongue cancer treated by interstitial brachytherapy (BRT) (uneventful recovery n = 16 , recurrence n = 5, severe soft tissue complication n = 3), follow-up examination were performed and both the margin and the vascular pattern were retrospectively assessed. We basically performed US examination at least once every 3 months after BRT within 1 year during follow-up period.

Infection-induced up-regulation of the costimulatory molecule 4-1BB in osteoblastic cells and its inhibitory effect on M-CSF/RANKL-induced in vitro osteoclastogenesis.

Bacterial infection sometimes impairs bone metabolism. In this study, we infected the osteoblastic cell line MC3T3-E1 with Mycobacterium bovis bacillus Calmette-Guérin (BCG) and identified genes that were up-regulated in the BCG-infected cells by the suppression subtractive hybridization method. A gene encoding 4-1BB (CD137), a member of the tumor necrosis factor-alpha receptor family, was found to be one of the up-regulated genes.

Change of sonographic findings on cervical lymph nodes before and after preoperative radiotherapy.

The aim of this study was to assess the changes in the power Doppler sonographic findings in patients with oral cancer undergoing chemotherapy and radiotherapy. We performed US examinations on 187 cervical lymph nodes (71 metastatic and 116 reactive nodes) excised from 52 patients before and after preoperative therapy. On Power Doppler images, we calculated the vascular index (VI) and evaluated the vascular pattern.

Laminin alpha2 is essential for odontoblast differentiation regulating dentin sialoprotein expression.

Laminin alpha2 is subunit of laminin-2 (alpha2beta1gamma1), which is a major component of the muscle basement membrane. Although the laminin alpha2 chain is expressed in the early stage of dental mesenchyme development and localized in the tooth germ basement membrane, its expression pattern in the late stage of tooth germ development and molecular roles are not clearly understood. We analyzed the role of laminin alpha2 in tooth development by using targeted mice with a disrupted lama2 gene.