Ameloblastoma, desmoplastic type: a case report with characteristic radiological presentation

Ameloblastoma, desmoplastic type, is a rare lesion for which radiographic images are even less common, and such lesions are sometimes considered to be variant types. It is defined as a variant of ameloblastoma with specific imaging and histological features. This lesion occurs with the same frequency in the maxilla and mandible, although the predominant site is the anterior-premolar site in both the mandible and maxilla. For our case of ameloblastoma, desmoplastic type, resected from the right anterior to premolar maxilla, the radiographic appearance and histopathological findings were compared. Computed tomography images revealed that the lesion had a multilocular structure with many smaller septa at its periphery. Although expansion toward the maxillary sinus was suggested radiologically, invasion of the mucosa into the floor of the maxillary sinus was found on histopathological examination.     

Facilitation of experimental tooth movement by NOC-18, a long-acting nitric oxide donor

PurposeIn orthodontic tooth movement, osteoclasts play a crucial role in bone resorption on the compression side of the alveolar bone. It has been reported that nitric oxide is involved in bone remodeling caused by mechanical loading, and we previously reported that NOC-18, a long-acting nitric oxide donor, augmented RANKL-induced osteoclast differentiation in mouse monocytic RAW264 cells as well as mouse bone marrow macrophages. In this study, we investigated whether NOC-18 facilitated experimental tooth movement in mice.Materials and methodsEight-week-old male ddY mice were used. Experimental tooth movement was induced by the insertion of an orthodontic elastic between the left maxillary first molar and second molar. Just after the insertion of the elastic, NOC-18 was intraperitoneally administered once, and mice were killed after 3 days. For the detection of osteoclasts, HE staining, TRAP staining, and immunostaining for cathepsin K were performed.ResultsAn intraperitoneal injection of NOC-18 significantly increased the distance of experimental tooth movement. Furthermore, the number and area of osteoclasts on the compression side of the alveolar bone surface was significantly higher in the NOC-18 group.ConclusionThese results suggested that systemic administration of NOC-18 might have some effect to facilitate experimental tooth movement in mice via the augmentation of osteoclast differentiation on the compression side of the alveolar bone.     

Six-transmembrane epithelial antigen of prostate4 (STEAP4) is a tumor necrosis factor alpha-induced protein that regulates IL-6, IL-8, and cell proliferation in synovium from patients with rheumatoid arthritis

Human six-transmembrane epithelial antigen of prostate4 (STEAP4), an ortholog of mouse tumor necrosis factor-α-induced adipose-related protein (TIARP), plays a role in tumor necrosis factor (TNF)-dependent arthritis models. However, its role in rheumatoid arthritis (RA) is still obscure. This study explored such a role for STEAP4. The expressions of STEAP4, TNFα, and IL-6 were compared in synovia of RA and osteoarthritis patients. STEAP4 induction was examined in TNFα-stimulated fibroblast-like synoviocytes (FLS) in vitro. FLS (with/without TNFα stimulation) were also analyzed for IL-6 expression after STEAP4 knockdown, using siRNA or transfection with STEAP4-plasmid DNA. IL-8, cell proliferation, and apoptosis were also evaluated in STEAP4-overexpressing FLS. The expression of STEAP4 in joints correlated with TNFα expression, specifically in RA synovium. In the cultured FLS, STEAP4 protein expression was augmented by TNFα activation, and localized in endosomal/lysosomal compartments. STEAP4 downregulation by siRNA enhanced the expression of IL-6 mRNA, while STEAP4 overexpression suppressed IL-6 and IL-8 expression, inhibited cell proliferation, and induced apoptosis via caspase-3. The results indicated that human STEAP4 is regulated by TNFα in synovium, where it controls IL-6 secretion and proliferation of FLS, suggesting that STEAP4 might potentially suppress the pathogenesis of TNFα-induced arthritis such as RA.     

Acute limbic encephalitis with focal hyperperfusion on single photon emission computed tomography

Here we report an 11-year-old boy with acute encephalopathy with neuropsychiatric symptoms. The patient had mildly decreased consciousness, delirious behavior, and affective changes next day of fever onset. Hematologic, biochemical, and metabolic examinations were unremarkable. CSF analysis revealed cell counts of 278 cells/mm³ and a protein level of 87 mg/dL. Although MRI revealed no abnormal findings, an increase in regional cerebral blood flow was present in the bilateral frontal lobes, mesial temporal lobes, and basal ganglia on single photon emission computed tomography. The measurement of the concentrations of biomarkers such as cytokines in the patient’s serum and cerebrospinal fluid revealed elevated levels of IL-4 and TNF-α in the cerebrospinal fluid. Immunohistochemical studies applying control human brain sections did not demonstrate the presence of autoantibodies. We considered that innate immunity rather than autoantibody response may have contributed to the neuropsychiatric symptoms of our patient. These results suggest heterogeneity of patients with acute encephalopathy with neuropsychiatric symptoms.     

Hemodynamic factor evaluation using computational fluid dynamics analysis for de novo bleb formation in unruptured intracranial aneurysms

Neurological Sciences - Although bleb formation increases the risk of rupture of intracranial aneurysms, previous computational fluid dynamic (CFD) studies have been unable to identify robust...