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Background Increasing evidence suggests a causal link between periodontitis and cognitive disorders. Systemic inflammation initiated by periodontitis may mediate the development of cognitive impairment. Our study aims to investigate the effect of ligature-induced periodontitis on cognitive function and the role of signal transducers and activators of transcription 3 (STAT3) in this process. Materials and methods Ligature-induced periodontitis was established, and the rats were treated intraperitoneally with/without the pSTAT3 inhibitor cryptotanshinone (CTS). Alveolar bone resorption and periodontal inflammation were detected by micro-computed tomography analysis and histopathological evaluation. Locomotor activity and cognitive function were evaluated by the open field test and the Morris water maze test, respectively. The activation of microglia and astrocytes in the hippocampus and cortex was assessed by immunohistochemistry (IHC). The expression of interleukins (IL-1β, IL-6, IL-8, IL-21) in both the periphery and cortex was evaluated by RT-PCR and ELISA. The expression of TLR/NF-κB and ROS cascades was evaluated by RT-PCR. The expression of pSTAT3 and the activation of the STAT3 signaling pathway (JAK2, STAT3, and pSTAT3) in the periodontal tissue and cortex were assessed by IHC and Western blot. The expression of amyloid precursor protein (APP) and its key secretases was evaluated by RT-PCR. The level of amyloid β-protein (Aβ) and the ratio of Aβ1-40/1-42 were measured via ELISA in the plasma and cortex while IHC was used to detect the level of Aβ1-42 in the brain. Results In periodontal ligature rats, significant alveolar bone resorption and local inflammatory cell infiltration were present. Apparent increases in inflammatory cytokines (IL-1β, IL-6, IL-8, and IL-21) were detected in peripherial blood and brain. Additionally, spatial learning and memory ability was impaired, while locomotor activity was not affected. Activated microglia and astrocytes were found in the cortex and hippocampus, presenting as enlarged cell bodies and irregular protrusions. Levels of TLR/NF-kB, PPAR and ROS were altered. The STAT3 signaling pathway was activated in both the periodontal tissue and cortex, and the processing of APP by β- and γ-secretases was promoted. The changes mentioned above could be relieved by the pSTAT3 inhibitor CTS. Conclusions Ligature-induced periodontitis in rats resulted in systemic inflammation and further abnormal APP processing, leading to cognitive impairments. In this progress, the activation of the STAT3 signaling pathway may play an important role by increasing inflammatory load and promoting neuroinflammation.

Periodontitis is one of the most common oral diseases worldwide, and it is associated with various systemic diseases, including cognitive diseases. STAT3 regulates the inflammatory cascade and influences adaptive immunity by modulating Th17/Treg cell differentiation. In this study, we aimed to explore the effect of adaptive immunity inside and outside the brain on the association between periodontitis and cognitive impairment and understand the role of the STAT3 signaling pathway. We established Porphyromonas gingivalis LPS-induced periodontitis mice models by injecting P. gingivalis LPS into the gingival sulcus of mice. Behavioral tests showed that learning and memory abilities were impaired. The flow cytometry data showed an imbalance in the Th17/Treg ratio in the blood and brain samples of the mice. The expression of Th17-related cytokines (IL-1β, IL-17A, IL-21, and IL-22) increased, whereas that of Treg-related cytokines (IL-2 and IL-10) decreased in both the blood and the brain. The level of LPS increased and the STAT3 signaling pathway was activated during this process. These effects were reversed by C188-9, a STAT3 inhibitor. In conclusion, P. gingivalis LPS-induced periodontitis may promote the occurrence and progression of cognitive impairment by modulating the Th17/Treg balance inside and outside the brain. The STAT3 signaling pathway may have immunoregulatory effects on the mouth-to-brain axis.

To evaluate the association between periodontitis and Alzheimer's disease.Databases of PubMed, Embase, CNKI, VIP and WanFang databases were searched for the relevant observational studies focusing on the association between periodontitis and Alzheimer's disease. The deadline was January 2019. Data quality evaluation and extraction were independently conducted by two authors. Meta analysis was performed using RevMan 5.2 software.Four case-control, five cross-sectional and two cohort studies were included. One cohort study and four case-control studies treated periodontitis as the exposure factor, all five cross-sectional studies and the other cohort study treated Alzheimer's disease as the exposure factor. The results of meta analysis showed that patients with periodontitis had a higher risk of Alzheimer's disease (RR=1.22, 95%CI: 1.13-1.33, P0.00001), and the risk was more higher in patients with severe periodontitis(RR=1.54, 95%CI:1.05-2.26, P=0.030.05); but there was no significant difference in the risk of Alzheimer's disease in patients with moderate periodontitis (RR=1.19, 95%CI: 0.98-1.44, P=0.070.05). The results of meta-analysis also showed that probing depth in patients with Alzheimer's disease was significantly higher than that of the control group (MD=2.58, 95%CI: 0.17-4.99, P=0.040.05), as well as clinical attachment loss (MD=1.27, 95%CI: 0.43-2.10, P=0.0030.05), plaque index (MD=1.14, 95%CI: 0.85-1.44, P0.00001) and the percentage of bleeding on probing (MD=21.11%, 95%CI: 18.23%-23.99%, P0.00001). Furthermore, the number of present teeth in patients with Alzheimer's disease was significantly less than that of the control group (MD=-3.77, 95% CI: -6.89- -0.65, P=0.020.05).The current evidence indicates that periodontitis is associated with Alzheimer's disease and patients with periodontitis (especially severe periodontitis) probably have a higher risk of developing Alzheimer's disease, and patients with Alzheimer's disease tend to have poorer periodontal health. However, the number of existing studies is limited and more clinical evidences are needed to support the correlation between these two diseases.

Background Mucosal neuroma (MN) is a benign neural tumor of peripheral nerves histologically characterized by irregular tortuous bundles of nerve cells with prominent perineurium that lie scattered throughout the submucosa. The tumor is usually associated with the multiple endocrine neoplasia type 2B (MEN 2B) but rarely occurs without the other components of MEN 2B. We present a case of solitary MN without MEN 2B that occurs in the maxillary incisor gingival papilla that has not been reported yet and review the literature. Case presentation: A 29-year-old woman presented to our outpatient department with an upper anterior teeth gingiva painless mass for 2-year. Intraoral examination revealed a small, tough, basal wide, well-defined mass in the labial gingival papilla between maxillary central incisor. Excisional biopsy showed that it was characterized by nerve bundles in various sizes surrounded by normal connective tissue in the submucosa under HE staining; Immunohistochemically, the mass showed strongly positive staining of S-100 protein, NSE,NF and weakly positive of EMA. The Laboratory examination and ultrasonography showed no signs of MEN 2B. In the first 6 months of follow-up, there was no evidence of recurrence and other components of MEN 2B. The patient was asymptomatic and she is still being followed up every 6 months. Based on these features, the lesion was finally diagnosed as a solitary gingival MN. Conclusions This study showed a rare solitary MN in the gingiva papilla without MEN 2B that has not been reported yet. The histopathological evaluation can be helpful in the differential diagnosis of MN. It is hoped that a greater understanding of solitary MN without MEN 2B in the oral cavity will avoid potential misdiagnosis, and contribute to determining the correct management, which appears to be complete surgical excision with close follow-up for recurrence and other components of MEN 2B surveillance.

Background: Increasing evidence suggests a causal link between periodontitis and Alzheimer’s disease (AD). Systemic inflammation initiated by periodontitis may mediate the development of AD. Our study aims to investigate the effect of ligature-induced periodontitis on cognitive function and the role of STAT3 in this process.Materials and Methods: Ligature-induced periodontitis was established, and the rats were treated intraperitoneally with/without the pSTAT3 inhibitor cryptotanshinone (CTS, 5 mg/kg). Alveolar bone resorption and periodontal inflammation were detected by micro-computed tomography (micro-CT) analysis and histopathological evaluation. The expression of cytokines (IL-1β, IL-6, IL-8, IL-21) in the periphery was evaluated by RT-PCR and ELISA. Locomotor activity and cognitive function were evaluated by the open field test and the Morris water maze test, respectively. The activation of microglia and astrocytes was assessed by immunohistochemistry. In the cortex, the cytokines mentioned above were also detected, while the activation of the STAT3 signalling pathway (JAK2, STAT3, and pSTAT3) was assessed by Western blotting. The expression of amyloid precursor protein (APP) and its key secretase enzymes was evaluated by RT-PCR, while the total Aβ and the ratio of Aβ1-40/1-42 were measured via ELISA.Results: In periodontal ligature rats, significant alveolar bone resorption and local inflammatory cell infiltration were present. Apparent increases in inflammatory cytokines (IL-1β, IL-6, IL-8 and IL-21) were detected; this change was relieved by the pSTAT3 inhibitor CTS. Additionally, spatial learning and memory function was impaired, while locomotor activity was not affected. Activated microglia and astrocytes were found in the cortex and hippocampus. In the cortex, these inflammatory cytokines showed similar changes when the STAT3 signalling pathway was activated. The processing of APP by β- and γ-secretases was promoted, and both the total Aβ and the ratio of Aβ1-40/1-42 were upregulated. Changes in the brain were also attenuated by CTS.Conclusions: Ligature-induced periodontitis in rats resulted in systemic inflammation and further impairments in cognitive function, leading to AD-like pathology. The activation of the STAT3 signalling pathway may play an important role in this process by increasing inflammatory load in both the periphery and brain, promoting neuroinflammation and modulating APP processing. This study may provide novel insights into periodontal intervention strategies and potential targets for AD prevention.

There exists a constant value of $H(z)$ at $z=-1$ when in $\omega$CDM universe with $\omega > -1$, which is independent on other cosmological parameters. We first combine this theoretical $H(z)$ value with the latest 43 observational $H(z)$ data (OHD) to perform the model-independent Gaussian Processes (GP) and constrain the Hubble constant. We obtain $H_0$=67.67$\pm3.03\ {\rm km\ s^{-1} Mpc^{-1}}$, which is in agreement with $H_0$ values from Plank Collaboration (2015) ($0.24 \sigma $ tension) but a larger deviation from Riess et al. (2016) ($1.60 \sigma $ tension), while $H_0$=71.09\ $\pm3.71\ {\rm km\ s^{-1} Mpc^{-1}}$ $ (0.64 \sigma $ tension) by only using latest 43 OHD. Using this $H_0$ value, we perform $\chi^2$ statistics with Markov Chain Monte Carlo (MCMC) method to constrain cosmological parameters. We obtain $\Omega_M=0.26 \pm 0.02$ and $\omega=-0.85 \pm 0.06$ in flat $\omega CDM$ model, and $\Omega_M=0.27\pm 0.04 , \Omega_\Lambda=0.80 \pm 0.12$ and $\omega=-0.82 \pm 0.07$ in non-flat $\omega CDM$ model, which are larger than those not using the theoretical $H(z)$ value.

To assess the validity of the Demirjian and Willems dental age estimation methods in a population of Eastern Chinese 11-18-year-old subadults.A total of 1622 orthopantomograms (787 boys and 835 girls) aged from 11.00 to 18.99 years old from a Chinese Han population were evaluated in the study. Dental ages were calculated using both Demirjian and Willems method. Statistical significance was set at p0.05 and for each method, discrepancies between chronological age (CA) and dental age (DA) were statistically analyzed by paired t-tests. Special age interval analysis was conducted by Chi-square tests to compare the accuracy of the Demirjian and the Willems methods.Demirjian method underestimated CA 0.66±1.45 y (p0.001) in boys and 0.62±1.61 y (p0.001) in girls while Willems method underestimated 0.90±1.32 y (p0.001) and 0.97±1.56 y (p0.001) in boys and girls, respectively. The mean absolute error (MAE) value between the CA and the DA (CA-DA) using the Demirjian method and the Willems method were 1.31 and 1.29 y for boys, respectively, and 1.35 and 1.43 y for girls, respectively.It is suggested that the Demirjian method was found to be more accurate compared with the Willems method. However, the Demirjian method may not be satisfactory for 11-18-year-old children of Eastern China. It is recommended that a modified Demirjian method for better dental age estimation for Eastern Chinese juvenile individuals.

X-ray imaging has a very important role in life sciences and material microstructure analysis and other applications. One of the core components of X-ray imaging equipment is the X-rays-visible light conversion screen. Flashing transparent film is an effective way to achieve high spatial resolution X-ray imaging. M'-type LuTaO₄: Eu³+ is an excellent scintillation material. It has high light yield, high density, good radiation hardness and good chemical stability. Therefore, to research and develop the transparent conversion screen with M'-type LuTaO⁴: Eu+ is very important for the application of X-ray detector in high spatial resolution X-ray imaging. In this paper, the M'-type LuTaO₄:Eu³+ transparent scintillator films were successfully prepared from the inorganic salt and 2-methoxyethanol solution containing polyvinylpyrrolidone (PVP) via sol-gel technique, and transmittance, photoluminescence, X-ray excitation emission spectral and spatial resolution, and a series of film properties were characterized. A film thickness of about 2.1 µm was achieved after 8 coatings. The thick film was homogeneous and crack free, and the transmittance was approximately 70% in its emission region. The spatial resolution of the thick film was 1.5 µm, which measured by the standard spatial resolution panels. An X-ray imageof fruit fly was obtained by using this thick film. Additionally, thesol-gel derived M'-type LuTaO₄:Eu³+ thick film revealed excellent photoluminescence and X-ray excited luminescence per- formances. All results indicated that the M'-type LuTaO⁴:Eu³+ thick films have satisfied the essential requirements for applications in high-spatial-resolution X-ray imaging.