A subacute epidural haematoma extending over the occipital region and posterior cranial fossa due to a laceration in the transverse sinus.

A 6-year-old male was found dead on his stomach with massive reddish vomiting from his mouth and nose. Postmortem cranial CT revealed an epidural haematoma in the left occipital region, but the cause and origin of the haematoma were unclear. An autopsy revealed that the epidural haematoma expanded over the left temporal region and the left side of the occipital region and posterior cranial fossa, and its origin was a laceration in the left transverse sinus induced by diastases in the left lambdoidal and occipitomastoid sutures. A pathohistological examination revealed that one portion of the haematoma was an early-stage hemorrhage, while the other portion extended approximately 1 week after the hemorrhage. Moreover, approximately 1 week elapsed after the laceration of the transverse sinus. Thus, we believe that the primary haematoma was induced by the laceration in the transverse sinus approximately 1 week before death, but the haematoma ceased to enlarge due to hemostasis. However, later, the size of the haematoma rapidly increased again due to rebleeding from the laceration, which led to intracranial hypertension. Consequently, we diagnosed the direct cause of death as choking due to vomit aspiration that resulted from intracranial hypertension induced by a subacute epidural haematoma.

Effects of a Janus kinase inhibitor, pyridone 6, on airway responses in a murine model of asthma.

Th2 cytokines and their downstream Janus kinase (JAK)-signal transducer and activation of transcription (STAT) pathways play a critical role in allergic asthma. We studied the effects of a pan-JAK inhibitor, pyridone 6 (P6), on asthmatic responses in a mouse model and investigated the mechanism for its biological effects. Mice were sensitized and challenged by ovalbumin (OVA). P6 treatment during the challenge phase suppressed eosinophilia in bronchoalveolar lavage (BAL) fluids but did not affect airway hyperresponsiveness (AHR). To improve the efficacy of the JAK inhibitor, P6 was encapsulated in polylactic-coglycolic acid nanoparticles (P6-PLGA). P6-PLGA treatment just before OVA challenge suppressed both airway eosinophilia and AHR. Although the IL-13 levels in BAL fluids and the OVA-specific IgE levels in serum after the challenge phase treatment with P6-PLGA were similar to those after a sham treatment, the eotaxin levels in BAL fluids and lung mCLCA3/Gob-5 expression were decreased in P6-PLGA-treated mice. Interestingly, the local IL-13 levels and serum OVA-specific IgE were decreased, while IL-17-producing T cells were increased by P6-PLGA treatment during the sensitization plus challenge phases. In vitro, P6 strongly suppressed the differentiation of Th2 from naive CD4 T cells, but it partly enhanced Th17 differentiation. P6 potently suppressed IL-13-mediated STAT6 activation and mCLCA3/Gob-5 expression in mouse tracheal epithelial cells. These findings suggest that the JAK inhibitor P6 suppresses asthmatic responses by inhibiting Th2 inflammation and that application of PLGA nanoparticles improves the therapeutic potency of P6.

Airflow limitation and tongue microbiota in community-dwelling elderly individuals.

Numerous oral indigenous microorganisms are constantly introduced into the stomach via the laryngopharynx, and a portion of these microorganisms irregularly reaches the lower airways and lungs. This study investigated the association between airflow limitation and the status of tongue microbiota, which is a primary source of ingested oral bacterial populations. The study population consisted of 484 community-dwelling adults aged 70-80 years inhabiting Hisayama town, Japan, who underwent a regular health examination including dental examination and spirometry test in 2016. The bacterial density and composition of their tongue microbiota were determined using a previously used 16S rRNA gene to understand their relationship with oral health conditions. The present cross-sectional study compared the tongue microbiota status between elderly individuals with airflow limitation and those with normal airflow. The total bacterial density of the tongue microbiota of individuals with airflow limitation was significantly higher than that of individuals with normal airflow. Logistic regression analysis demonstrated that a high-biomass tongue microbiota was significantly associated with airflow limitation after adjustment for smoking intensity and other covariates (adjusted OR 1.61, 95% CI 1.01-2.60). Of the predominant commensals, higher amounts of Prevotella melaninogenica and Actinomyces odontolyticus were associated with a higher prevalence of airflow limitation. These results indicate that increased bacterial burden in the tongue microbiota is associated with a higher prevalence of airflow limitation.

Macrophage-mediated repair of intraepithelial damage in rat oral mucosa.

OBJECTIVE: It is important to protect the patient's oral mucosa from injury caused by inappropriate oral care. We established anin vivo model of intraepithelial injury of the oral mucosa and assessed the effects of inappropriate dental apparatus use on inflammatory response of macrophages in rats. DESIGN: Using this model, swabbing was performed to the labial mucosa of rats with the interdental brush, and the tissue samples were processed for histological evaluation. RESULTS: CD 68-positive macrophage-like cells appeared only in the subepithelial region after intraepithelial injury in the presence and absence of antibiotics. After intraepithelial injury, interleukin-1ß levels did not increase beyond those observed in intact rats. The number of bacteria in the lip increased slightly and decreased promptly. In the ear, intraepithelial injury caused an inflammatory response with macrophages infiltrating into the intraepithelial region as well as the subepithelial region, increased interleukin-1ß production, and high bacterial levels around tissues. CONCLUSION: Our results highlight the importance of protecting against the intraepithelial injury during oral care procedures, and these findings would contribute to oral care risk management in the future.

Periodontal status and lung function decline in the community: the Hisayama study.

This study aimed to determine whether periodontal status is related to a decline in lung function in a general Japanese population. We followed a total of 1,650 community-dwelling individuals (≥40 years) without chronic obstructive pulmonary disease, with at least one teeth, for 3 years. Periodontal status was assessed at baseline by clinical attachment loss (CAL) and probing pocket depth (PPD) at two sites for each tooth, and the mean values were calculated for each subject. Lung function was measured at baseline and follow-up using spirometry, and longitudinal decline in forced expiratory volume in one second (FEV1) was calculated. Multivariate Poisson regression with robust error variance was used to estimate risk ratio (RR). After adjusting for potential confounders including smoking status, there was a tendency for the adjusted RR of developing rapid lung function decline (≥160 mL/3years, the highest quartile of the distribution of FEV1 declines) to increase as mean CAL levels increased (P trend = 0.039). Likewise, a positive association was observed between mean PPD levels and RR of developing rapid lung function decline (P trend = 0.047). Our findings suggest deterioration of periodontal status could be a risk factor for rapid lung function decline in the general Japanese population.

Induction of salivary antibodies to inhibit Candida albicans adherence to human epithelial cells by tonsillar immunization in rabbits.

To examine the possibility of a vaccine for Candida albicans infection in the oral cavity, we induced salivary antibodies by immunization of killed-C. albicans ATCC 18804 on the palatine tonsils of rabbits. The enzyme-linked immunosorbent assay reaction of salivary antibodies was high against C. albicans serotype A. The saliva antibodies greatly inhibited C. albicans adherence to cloned epithelial cells from human gingiva. Tonsillar immunizations of C. albicans ATCC 18804 induce salivary antibodies that prevent C. albicans adherence to epithelial cells, and thus should prove useful in the prevention of oral candidiasis caused by C. albicans serotype A.

New pitfalls of high-density postmortem computed tomography.

An 80-year-old female was transferred to the hospital due to a traffic accident. Multiple cranial bone fractures with intracranial hemorrhage and intracranial air were detected. Despite treatment, the patient died after 6h. Twenty-one hours after the patient died, her whole body was scanned by postmortem CT, and a region of high density was detected within the left putamen. The autopsy revealed a cerebral contusion and multiple skull base fractures. Moreover, superabsorbent polymers (SAPs) were found within the left lateral ventricle and adjacent to the putamen, which appeared as a high-density lesion on postmortem CT at the left putamen, where the SAPs were compacted. Both ante- and postmortem conditions should be considered to prevent misdiagnoses based only on postmortem CT.

Perspectives on a new educational system for dental hygiene students in Japan.

The purpose of this article is to report changes to dental hygiene education in Japan and to evaluate the successful implementation of these changes in 2010. The legislative change that began in 2005 revised the length of education for dental hygiene students from two years to three or four years (the mandate was three years), which has led to a dramatic change in program curriculum. After a five-year moratorium, a new curriculum has been established for dental hygiene education in Japan. The new curriculum provides students the requisite knowledge to effectively perform the latest dental hygiene procedures. Although the change of the educational system from the present mandatory three-year to the new four-year programs poses many administrative problems, we believe this shift will ultimately provide a more thorough and in-depth education for students.