Background. The present study was undertaken to determine the effect of local and systemic inflammation on the quantity and localization of gingival mesenchymal stem cells (gMSCs). Methods. Gingival samples were collected from 34 systemically healthy (group 1) and 10 consenting adult patients with type II diabetes mellitus (T2DM) (group 2), who had reported for various dental treatments, requiring excision of gingival tissues as part thereof. The tissue samples were further stratified into three categories: healthy gingiva, gingivitis-affected and periodontitis-affected. Samples mounted on slides were stained with hematoxylin and eosin (H&amp;amp;E) while CD105 antibody was used for immunohistochemistry staining. Immuno-positive cells were identified as gMSCs. Three gMSCpopulated areas in each sample were selected to determine the density of gMSCs. Results. The density of gMSCs was significantly higher (P<0.05) in sections of gingival tissues affected by gingivitis and periodontitis compared to those of normal gingiva. However, there were no significant differences in the densities of gMSCs in tissues of patients with T2DM and those of healthy subjects. Conclusion. Local inflammatory status appeared to increase the density of gMSCs. In the presence of periodontitis, an added low-grade systemic inflammation (T2DM) did not appear to affect the density of gMSCs.

Introduction:Diffuse midline glioma with H3-K27M mutation is an infiltrative high-grade glioma, with predominantly astrocytic differentiation.Patient concerns:A 54-year-old Chinese woman presented with memory loss for a month and walking instability for 15 days.Diagnosis:Magnetic resonance imaging showed a mass shadow of isometric T1 and slightly longer T2 with mild mixed signals in the third ventricle of the suprasellar region. Histologically, the tumor was primarily sheet-like, with many “anucleate areas” composed of long and thin fibrillary processes of the bipolar cells, which formed “whorls.” The neoplastic nuclei were ovoid and moderate in size. The tumor showed brisk mitotic activity and vascular proliferation, with no necrosis. In addition to histone H3K27M mutation, immunohistochemical staining showed that the tumor cells were positive for glial fibrillary acidic protein, oligodendrocyte transcription factor 2, alpha-thalassemia/mental retardation syndrome X, S-100 and Vimentin. The “anucleate areas” were positive for glial fibrillary acidic protein and negative for synaptophysin. The Ki-67 proliferation index was about 10%. Molecular genetic analyses detected H3F3A K27M mutation, but no mutations in IDH1 or IDH2, TERT promoter mutations, MGMT promoter methylation, KIAA1549-BRAF fusion or deletion of 1p/19q were found. Based on these findings, the patient was diagnosed as diffuse midline glioma with H3-K27M mutation in the third ventricle, corresponding to WHO grade 4.Interventions:A craniotomy with total excision of the tumor was performed.Outcomes:After surgery, she was routinely treated with temozolomide for chemotherapy and synchronous radiotherapy. It has been 11 months now, and the patient is living well.Conclusion:This case report provides information on the microscopic morphological features of diffuse midline glioma with H3K27M mutation, which can help pathologists to make a definitive diagnosis of this tumor.

Rationale: Astroblastoma is a rare tumor of the central nervous system with uncertain biological behavior and origin. Its histopathological features have been well established, while, to our knowledge, astroblastoma with oligodendroglial-like cells have not been reported.Patient concerns: A 15-year-old girl presented with nausea, vomiting, headache, and visual disturbance.Diagnosis: Magnetic resonance imaging revealed a large neoplasm in the left temporal. Histologically, the tumor showed solid and pseudopapillary structure. Immunohistochemical staining showed that the tumor cells were positive for glial fibrillary acidic protein and vimentin. The oligodendroglial-like cells were positive for glial fibrillary acidic protein, vimentin, and oligodendrocyte transcription factor 2. The antigen KI67 labeling index was about 4%. Sequencing for isocitrate dehydrogenase (IDH) 1 codon 132 and IDH2 codon 172 gene mutations showed negative results. Furthermore, fluorescent analysis revealed neither 1p nor 19q deletion in the lesion. Based on these findings, the girl was finally diagnosed as astroblastoma.Interventions: A craniotomy with total excision of the tumor was performed.Outcomes: The follow-up time was 1 year, no evidence of disease recurrence was found in magnetic resonance imaging.Lessons: Cerebral astroblastoma with oligodendroglial-like cells is a clinically rare tumor of central nervous system. Clear distinction and diagnosis are critical. Abbreviations: EMA = epithelial membrane antigen, FISH = fluorescent in situ hybridization, GFAP = glial fibrillary acidic protein, IDH = isocitrate dehydrogenase, NeuN = neuronal nuclear antigen, Olig-2 = oligodendrocyte transcription factor 2, P53 = tumor protein 53, Syn = synaptophysin.