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Abstract Background Adenocarcinoma not otherwise specified (NOS) is an uncommon malignant minor salivary gland tumor. We report gallium-67 SPECT/CT and diffusion-weighted MRI (DWI) in the palatal tumor, especially a rare case with adenocarcinoma NOS. Case presentation An 85-year-old female patient presented with swelling on the palate within 3 months. DWI and apparent diffusion coefficient (ADC) maps indicated high and low signal intensities on the lesion, respectively. ADC value of the lesion was 0.58 × 10–3 mm2s−1. Gallium-67 SPECT/CT showed increased uptake on the lesion and no metastasis. The maximum SUV for the palatal lesion was 7.36. Histopathological diagnosis by a biopsy was adenocarcinoma NOS. Conclusion The gallium-67 SPECT/CT and DWI should be effective for assessment of the palatal tumor.

Introduction: The intentional perforation of the pulp chamber floor before tooth replantation promotes pulpal healing by facilitating the revascularization of the pulp cavity. This study aimed to elucidate the effects of this method on the dynamics of quiescent dental pulp stem cells (DPSCs). Methods: The right and left maxillary first molars of Crlj:CD1 mice and TetOP-histone 2B (H2B)-green fluorescent protein (GFP) mice were extracted. The left molars were immediately replanted as the control group (CG), whereas the pulp chamber floor of the right molars were perforated before the tooth was replanted as the experimental group (EG). Immunohistochemistry for Nestin and GFP, and quantitative RT-PCR for Nestin, Opn, CD11c, and Oct3/4 mRNA were performed. Results: The rate of Nestin-positive perimeter along the pulp–dentin border in the EG tended to be higher than that of the CG at days 5 and 7 and was significantly increased between days 3 and 7. The rate of GFP-positive cells in the EG was significantly higher than that of the CG at days 5 and/or 7 in the mesial and middle coronal pulp. CD11c mRNA in the EG at day 5 was significantly higher than that of the CG and tended to be higher than that of the CG during the observation period. Oct3/4 mRNA expression in the EG was significantly higher than that of the CG at day 7. Conclusions: The current experimental model demonstrated the promotion of the survival of DPSCs and their differentiation into odontoblast-like cells (OBLCs). Thus, the use of this model is expected to clarify the crosstalk mechanism between immune cells, including macrophages and dendritic cells, and DPSCs with regards to pulpal healing after tooth replantation. It also provides insight into the differentiation process of DPSCs into OBLCs.

Abstract Background SPECT/CT has been applied for preoperative planning of MRONJ. Furthermore, the SUV using bone SPECT/CT has enabled quantitative analysis of jaw lesions. This study aimed to evaluate the role of preoperative SPECT/CT SUVs in MRONJ, especially SPECT/CT in relation to CBCT and histopathological findings of the resected bone of mandibulectomy. The preliminary study was conducted on five MRONJ patients who underwent mandibulectomy after SPECT/CT. Results The SUVmax and SUVmean of MRONJ in all cases (19.5 ± 5.6 and 5.5 ± 0.8) were significantly higher than those of right side of the MRONJ (8.5 ± 2.0 and 2.7 ± 0.5) and left side of the MRONJ (7.2 ± 1.6 and 2.7 ± 0.4), respectively. The CBCT of all cases showed osteolytic and sclerotic internal texture and sequestrum. The histopathological characteristics of all cases showed necrotic bone and granulation tissue with the bone circumference surrounded by inflammatory cells. Conclusions The preliminary results indicated a difference between MRONJ and right and left sides of the MRONJ in SPECT/CT SUVs. The SUVs has enabled quantitative analysis for surgical planning of MRONJ.

Abstract Cyclic phosphatidic acid (cPA) is a lipid mediator, which regulates adipogenic differentiation and glucose homeostasis by suppressing nuclear peroxisome proliferator-activated receptor γ (PPARγ). Glycerophosphodiesterase 7 (GDE7) is a Ca2+-dependent lysophospholipase D that localizes in the endoplasmic reticulum. Although mouse GDE7 catalyzes cPA production in a cell-free system, it is unknown whether GDE7 generates cPA in living cells. Here, we demonstrate that human GDE7 possesses cPA-producing activity in living cells as well as in a cell-free system. Furthermore, the active site of human GDE7 is directed towards the luminal side of the endoplasmic reticulum. Mutagenesis revealed that amino acid residues F227 and Y238 are important for catalytic activity. GDE7 suppresses the PPARγ pathway in human mammary MCF-7 and mouse preadipocyte 3T3-L1 cells, suggesting that cPA functions as an intracellular lipid mediator. These findings lead to a better understanding of the biological role of GDE7 and its product, cPA.

Hyperplastic dental follicles (HDFs) represent odontogenic hamartomatous lesions originating from the pericoronal tissues and are often associated with impacted or embedded teeth. These lesions may occasionally feature unique calcifying bodies, known as calcifying whorled nodules (CWNs), characterized by stromal cells arranged in a whorled or spiral fashion. CWNs are typically observed in multiple calcifying hyperplastic dental follicles or regional odontodysplasia. In our study, we examined 40 cases of HDFs, including nine instances with characteristics of CWNs, referred to as calcifying hyperplastic dental follicles (CHDFs), which are infrequently accompanied by odontodysplasia. The median ages of the HDFs and CHDFs were 16 (ranging from 3 to 66) and 15 (ranging from 11 to 50) years, respectively. The lower third molars were the most frequently affected by HDSFs and CHDFs, followed by the upper canines. A histological examination was conducted on all 40 cases, with an immunohistochemical analysis performed on 21 of them. Among the cases with CWN, nine affected a single embedded tooth, with one exception. CWNs exhibited diverse calcifications featuring sparse or entirely deposited psammoma bodies, and some displayed dentinoid formation. Immunohistochemically, the stromal cells of HDFs were frequently positive for CD56 and nestin. By contrast, CWNs were negative for CD56 but positive for nestin as well as hairy and enhancer split 1 (HES1), with a few dentin sialoprotein (DSP)-positive calcified bodies. Our results revealed that hamartomatous CHDFs can impact multiple and single-embedded teeth. CWNs composed of nestin and HES1-positive ectomesenchymal cells demonstrated the potential to differentiate into odontoblasts and contribute to dentin matrix formation under the influence of HES1. This study is the first report documenting odontoblastic differentiation in HDFs. The rare occurrence of HDFs and CHDFs contributes to limited comprehension. To prevent misdiagnosis, a better understanding of these conditions is necessary.

Coronavirus disease 2019 (COVID-19) is a highly transmissible pandemic disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The characteristics of the disease include a broad range of symptoms from mild to serious to death, with mild pneumonia to acute respiratory distress syndrome and complications in extrapulmonary organs. Taste impairment and salivary dysfunction are common early symptoms in COVID-19 patients. The mouth is a significant entry route for SARS-COV-2, similar to the nose and eyes. The cells of the oral epithelium, taste buds, and minor and major salivary glands express cell entry factors for SARS-COV-2, such as ACE2, TMPRSS2, and Furin. We describe the occurrence of taste impairment and salivary dysfunction in COVID-19 patients and show immunohistochemical findings regarding the cell entry factors in the oral tissue. We review and describe the pathogeneses of taste impairment and salivary dysfunction. Treatment for the oral disease is also described. Recently, it was reported that some people experience persistent and prolonged taste impairment and salivary dysfunction, described as post-COVID-19 syndrome or long COVID-19, after the acute illness of the infection has healed. To resolve these problems, it is important to understand the pathogenesis of oral complications. Recently, important advances have been reported in the understanding of gustatory impairment and salivary dysfunction. Although some progress has been made, considerable effort is still required for in-depth elucidation of the pathogenesis.

Fe–Si–B–P–Cu nanocrystalline alloy were treated with ball-mill using a lubricant as a process control agent (PCA). The resulting alloy powder is a strong candidate material for soft magnetic composites. Two ball milling methods (continuous and interval) were employed to control the interactions between the PCA and the alloy surface, and their effect on the microstructure of the prepared alloy particles was investigated. The alloy sheet was broken into small pieces and deformed plastically into flake-shaped particles regardless of the ball milling method implemented. Friction-force microscopy of the alloy immersed in the PCA revealed that the friction coefficient of the alloy surface exposed to air for a certain period was higher than that of the unexposed alloy surface (immediately after polishing). During ball milling, the ratio of the newly generated surface to the oxidized surfaces of the alloy subjected to interval milling was smaller than that of the alloy subjected to continuous milling. Therefore, the friction coefficient of the surface of the alloy subjected to interval milling was higher than that of the alloy subjected to continuous milling. Synchrotron radiation analysis revealed that the alloy subjected to interval milling exhibited enhanced surface friction, showing an obvious steepness and inflection in the diffraction intensity as a function of the tilt angle based on the Schulz reflection method. This indicates formation of crystallographic texture in α-Fe grains in an amorphous matrix. Hence, we demonstrated successfully that the ball milling process induced a crystallographic texture in the Fe-based nanocrystalline alloy due to plastic deformation due to the enhanced surface friction. The surface of the alloy was prepared based on the effect of the interfacial interactions between the alloy surface and the PCA.

Objective: Activating transcription factor 4 (ATF4) is a transcriptional regulator of the unfolded protein response and integrated stress response (ISR) that promote the restoration of normal endoplasmic reticulum (ER) function. Previous reports demonstrated that dysregulation of the ISR led to development of severe diabetes. However, the contribution of ATF4 to pancreatic β-cells remains poorly understood. In this study, we aimed to analyze the effect of ISR enhancer Sephin1 and ATF4-deficient β-cells to clarify the role of ATF4 in β-cells under ER stress conditions. Methods: To examine the role of ATF4 in vivo, ISR enhancer Sephin1 (5 mg/kg body weight, p.o.) was administered daily for 21 days to Akita mice. We also established β-cell–specific Atf4 knockout (βAtf4-KO) mice that were further crossed with Akita mice. These mice were analyzed for characteristics of diabetes, β-cell function, and morphology of the islets. To identify the downstream factors of ATF4 in β-cells, the islets of βAtf4-KO mice were subjected to cDNA microarray analyses. To examine the transcriptional regulation by ATF4, we also performed in situ PCR analysis of pancreatic sections from mice and ChIP-qPCR analysis of CT215 β-cells. Results: Administration of the ISR enhancer Sephin1 improved glucose metabolism in Akita mice. Sephin1 also increased the insulin-immunopositive area and ATF4 expression in the pancreatic islets. Akita/βAtf4-KO mice exhibited dramatically exacerbated diabetes, shown by hyperglycemia at an early age, as well as a remarkably short lifespan owing to diabetic ketoacidosis. Moreover, the islets of Akita/βAtf4-KO mice presented increased numbers of cells stained for glucagon, somatostatin, and pancreatic polypeptide and increased expression of aldehyde dehydrogenase 1 family member 3, a marker of dedifferentiation. Using microarray analysis, we identified atonal BHLH transcription factor 8 (ATOH8) as a downstream factor of ATF4. Deletion of ATF4 in β-cells showed reduced Atoh8 expression and increased expression of undifferentiated markers, Nanog and Pou5f1. Atoh8 expression was also abolished in the islets of Akita/βAtf4-KO mice. Conclusions: We conclude that transcriptional regulation by ATF4 maintains β-cell identity via ISR modulation. This mechanism provides a promising target for the treatment of diabetes.

Lysophosphatidic acid (LPA) is a lipid mediator that regulates various processes, including cell migration and cancer progression. Autotaxin (ATX) is a lysophospholipase D-type exoenzyme that produces extracellular LPA. In contrast, glycerophosphodiesterase (GDE) family members GDE4 and GDE7 are intracellular lysophospholipases D that form LPA, depending on Mg2+ and Ca2+, respectively. Since no fluorescent substrate for these GDEs has been reported, in the present study, we examined whether a fluorescent ATX substrate, FS-3, could be applied to study GDE activity. We found that the membrane fractions of human GDE4- and GDE7-overexpressing human embryonic kidney 293T cells hydrolyzed FS-3 in a manner almost exclusively dependent on Mg2+ and Ca2+, respectively. Using these assay systems, we found that several ATX inhibitors, including α-bromomethylene phosphonate analog of LPA and 3-carbacyclic phosphatidic acid, also potently inhibited GDE4 and GDE7 activities. In contrast, the ATX inhibitor S32826 hardly inhibited these activities. Furthermore, FS-3 was hydrolyzed in a Mg2+-dependent manner by the membrane fraction of human prostate cancer LNCaP cells that express GDE4 endogenously but not by those of GDE4-deficient LNCaP cells. Similar Ca2+-dependent GDE7 activity was observed in human breast cancer MCF-7 cells but not in GDE7-deficient MCF-7 cells. Finally, our assay system could selectively measure GDE4 and GDE7 activities in a mixture of the membrane fractions of GDE4- and GDE7-overexpressing human embryonic kidney 293T cells in the presence of S32826. These findings allow high-throughput assays of GDE4 and GDE7 activities, which could lead to the development of selective inhibitors and stimulators as well as a better understanding of the biological roles of these enzymes.

Abstract The plant Cannabis sativa contains cannabinoids represented by Δ9-tetrahydrocannabinol, which exert psychoactivity and immunomodulation through cannabinoid CB1 and CB2 receptors, respectively, in animal tissues. Arachidonoylethanolamide (also referred to as anandamide) and 2-arachidonoylglycerol (2-AG) are well known as two major endogenous agonists of these receptors (termed “endocannabinoids”) and show various cannabimimetic bioactivities. However, only 2-AG is a full agonist for CB1 and CB2 and mediates retrograde signals at the synapse, strongly suggesting that 2-AG is physiologically more important than anandamide. The metabolic pathways of these two endocannabinoids are completely different. 2-AG is mostly produced from inositol phospholipids via diacylglycerol by phospholipase C and diacylglycerol lipase and then degraded by monoacylglycerol lipase. On the other hand, anandamide is concomitantly produced with larger amounts of other N-acylethanolamines via N-acyl-phosphatidylethanolamines (NAPEs). Although this pathway consists of calcium-dependent N-acyltransferase and NAPE-hydrolyzing phospholipase D, recent studies revealed the involvement of several new enzymes. Quantitatively major N-acylethanolamines include palmitoylethanolamide and oleoylethanolamide, which do not bind to cannabinoid receptors but exert anti-inflammatory, analgesic, and anorexic effects through receptors such as peroxisome proliferator-activated receptor α. The biosynthesis of these non-endocannabinoid N-acylethanolamines rather than anandamide may be the primary significance of this pathway. Here, we provide an overview of the biological activities and metabolisms of endocannabinoids (2-AG and anandamide) and non-endocannabinoid N-acylethanolamines.

Cone-beam computed tomography (CBCT) provides accurate anatomical details in three-dimensional and multiplanar reformation images for diagnosis and treatment planning. We examined one surgical specimen of medication-related osteonecrosis of the jaw (MRONJ) by CBCT. CBCT images of the surgical specimen of MRONJ showed osteolytic changes in the jaws, sclerotic lesion, and sequestrum separation. Furthermore, high-resolution mode (tube voltage, 90.0 kV; tube current, 4.00 mA; rotation time,16.8 s; field of view, 56 mm × 56 mm; thickness, 0.099 mm) was sharper than standard mode (tube voltage, 90.0 kV; tube current, 4.00 mA; rotation time, 16.8 s; field of view, 81 mm × 81 mm; thickness, 0.144 mm) and high-density mode (tube voltage, 90.0 kV; tube current, 4.00 mA; rotation time, 33.5 s; field of view, 81 mm × 81 mm; thickness, 0.144 mm). We showed that CBCT, especially the high-resolution mode, is useful for the evaluation of surgical specimen of the jaw, such as MRONJ. This report can be used for reference in future studies and in clinical settings.

Radiotherapy is the main treatment modality for nasopharyngeal carcinoma. However, ionizing radiation is itself a known carcinogen, and sarcomas can be a complication of treatment. Radiation-induced osteosarcomas in the head and neck are particular rare. Imaging studies of radiation-induced sarcomas in patients with head and neck carcinoma have been limited to case reports and relatively small case series. We report an unusual case of a radiation-induced osteosarcoma of the mandibular ramus following radiotherapy for nasopharyngeal carcinoma with computed tomography (CT) and magnetic resonance imaging (MRI). These findings can be helpful for differentiating osteosarcoma from other tumors of the mandible.

Idiopathic pulmonary fibrosis is a devastating disease with poor prognosis. The pathogenic role of the lysophospholipid mediator sphingosine-1-phosphate and its receptor S1PR2 in lung fibrosis is unknown. We show here that genetic deletion of S1pr2 strikingly attenuated lung fibrosis induced by repeated injections of bleomycin in mice. We observed by using S1pr2LacZ/+ mice that S1PR2 was expressed in alveolar macrophages, vascular endothelial cells and alveolar epithelial cells in the lung and that S1PR2-expressing cells accumulated in the fibrotic legions. Bone marrow chimera experiments suggested that S1PR2 in bone marrow-derived cells contributes to the development of lung fibrosis. Depletion of macrophages greatly attenuated lung fibrosis. Bleomycin administration stimulated the mRNA expression of the profibrotic cytokines IL-13 and IL-4 and the M2 markers including arginase 1, Fizz1/Retnla, Ccl17 and Ccl24 in cells collected from broncho-alveolar lavage fluids (BALF), and S1pr2 deletion markedly diminished the stimulated expression of these genes. BALF cells from bleomycin-administered wild-type mice showed a marked increase in phosphorylation of STAT6, a transcription factor which is activated downstream of IL-13, compared with saline-administered wild-type mice. Interestingly, in bleomycin-administered S1pr2-/- mice, STAT6 phosphorylation in BALF cells was substantially diminished compared with wild-type mice. Finally, pharmacological S1PR2 blockade in S1pr2+/+ mice alleviated bleomycin-induced lung fibrosis. Thus, S1PR2 facilitates lung fibrosis through the mechanisms involving augmentation of IL-13 expression and its signaling in BALF cells, and represents a novel target for treating lung fibrosis.

In designing motors, one must grasp the magnetic properties of electrical steel sheets considering actual conditions in motors. Especially important is grasping the stress dependence of magnetic power loss. This paper describes a newly developed apparatus to measure two-dimensional (2-D) magnetic properties (properties under the arbitrary alternating and the rotating flux conditions) of electrical steel sheets under compressive stress normal to the sheet surface. The apparatus has a 2-D magnetic excitation circuit to generate magnetic fields in arbitrary directions in the evaluation area. It also has a pressing unit to apply compressive stress normal to the sheet surface. During measurement, it is important to apply uniform stress throughout the evaluation area. Therefore, we have developed a new flux density sensor using needle probe method. It is composed of thin copper foils sputtered on electrical steel sheets. By using this sensor, the stress can be applied to the surface of the specimen without influence of this sensor. This paper described the details of newly developed apparatus with this sensor, and measurement results of iron loss by using are shown.

Cardiac fibroblasts, together with cardiomyocytes, occupy the majority of cells in the myocardium and are involved in myocardial remodeling. The lysophospholipid mediator sphigosine-1-phosphate (S1P) regulates functions of cardiovascular cells through multiple receptors including S1PR1-S1PR3. S1PR1 but not other S1P receptors was upregulated in angiotensin II-induced hypertrophic hearts. Therefore, we investigated a role of S1PR1 in fibroblasts for cardiac remodeling by employing transgenic mice that overexpressed S1PR1 under the control of α-smooth muscle actin promoter. In S1PR1-transgenic mouse heart, fibroblasts and/or myofibroblasts were hyperplastic, and those cells as well as vascular smooth muscle cells overexpressed S1PR1. Transgenic mice developed bi-ventricular hypertrophy by 12-week-old and diffuse interstitial fibrosis by 24-week-old without hemodynamic stress. Cardiac remodeling in transgenic mice was associated with greater ERK phosphorylation, upregulation of fetal genes, and systolic dysfunction. Transgenic mouse heart showed increased mRNA expression of angiotensin-converting enzyme and interleukin-6 (IL-6). Isolated fibroblasts from transgenic mice exhibited enhanced generation of angiotensin II, which in turn stimulated IL-6 release. Either an AT1 blocker or angiotensin-converting enzyme inhibitor prevented development of cardiac hypertrophy and fibrosis, systolic dysfunction and increased IL-6 expression in transgenic mice. Finally, administration of anti-IL-6 antibody abolished an increase in tyrosine phosphorylation of STAT3, a major signaling molecule downstream of IL-6, in the transgenic mouse heart and prevented development of cardiac hypertrophy in transgenic mice. These results demonstrate a promoting role of S1PR1 in cardiac fibroblasts for cardiac remodeling, in which angiotensin II-AT1 and IL-6 are involved.