Tooth Tissues of Certain Sharks and Lungfishes

A comparative odontologic study was conducted on teeth and their supporting tissues from extant sharks, fossil sharks, and living lungfishes using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) X-ray microprobe to investigate evolutionary changes in tooth structure of the fishes. No histological differences between the extant and fossil teeth of lamnoid sharks were observed. The weight percent of calcium in osteodentin of the fossil shark was higher than that in the extant shark. The weight percents of both P and Ca of tooth tissues in the giant extinct shark showed comparatively low values. Both the upper and lower jaws of the African lungfish possessed a pair of tooth plates composed of a very thin enamel, and layers of petrodentin and osteodentin. The radical osteodentin of the plates changed gradually, fusing with the jaw bones without distinct boundaries. SEM and EDS indicated the petrodentin contained bundles of fibers impregnated with hydroxyapatite crystals, and the enamel had plate-like crystals running at right angles to the tooth surfaces; no tubules were observed in this enamel. The total content of both P and Ca in the lungfish enamel is lower than those in the petrodentin and shark enameloid

Diagnostic accuracy of narrow-band imaging and pit pattern analysis significantly improved for less-experienced endoscopists after an expanded training program

Background: Previous reports assessing diagnostic skill using narrow-band imaging (NBI) and pit pattern analysis for colorectal polyps involved only highly experienced endoscopists. Objective: To evaluate diagnostic skills of less-experienced endoscopists (LEE group) for. differentiation of diminutive colorectal polyps by using NBI and pit pattern analysis with and without magnification after an expanded training program. Design: Prospective study. Patients: This study involved 32 patients with 44 colorectal polyps (27 adenomas and 17 hyperplastic polyps) of 5 mm that were identified and analyzed by using conventional colonoscopy as well as non-magnification and magnification NBI and chromoendoscopy followed by endoscopic removal for histopathological analysis. Intervention: Before a training course, 220 endoscopic images were distributed in randomized order to residents with no prior endoscopy experience (NEE group) and to the LEE group, who had performed colonoscopies for more than 5 years but had never used NBI. The 220 images were also distributed to highly experienced endoscopists (HEE group) who had routinely used NBI for more than 5 years. The images were distributed to the NEE and LEE groups again after a training class. Magnification NBI and chromoendoscopy images were assessed by using the Sano and Kudo classification systems, respectively. Main Outcome Measurements: Diagnostic accuracy and interobserver agreement for each endoscopic modality in each group. Results: Diagnostic accuracy was significantly higher, and kappa (kappa) values improved in the LEE group for NBI with high magnification after expanded training. Diagnostic accuracy and kappa values when using high-magnification NBI were highest among endoscopic techniques for the LEE group after such training and the HEE group (accuracy 90% vs 93%; kappa = 0.79 vs 0.85, respectively). Limitations: Study involved only polyps of <= 5 mm. Conclusion: Using high-magnification NBI increased the differential diagnostic skill of the LEE group after expanded training so that it was equivalent to that of the HEE group

2-Decenoic Acid Ethyl Ester, a Compound That Elicits Neurotrophin-like Intracellular Signals, Facilitating Functional Recovery from Cerebral Infarction in Mice

In our previous study, we found that trans-2-decenoic acid ethyl ester (DAEE), a derivative of a medium-chain fatty acid, elicits neurotrophin-like signals including the activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) in cultured mouse cortical neurons. Here, we examined the efficacy of intraperitoneal administration of DAEE on the treatment of a mouse model of the cerebral infarction caused by unilateral permanent middle cerebral artery occlusion (PMCAO). DAEE-treatment (100 μg/kg body weight injected at 0.5, 24, 48, 72 h after PMCAO) significantly restored the mice from PMCAO-induced neurological deficits including motor paralysis when evaluated 48, 72, and 96 h after the PMCAO. Furthermore, DAEE facilitated the phosphorylation of ERK1/2 on the infarction side of the brain when analyzed by Western immunoblot analysis, and it enhanced the number of phosphorylated ERK1/2-positive cells in the border areas between the infarction and non-infarction regions of the cerebral cortex, as estimated immunohistochemically. As the infarct volume remained unchanged after DAEE-treatment, it is more likely that DAEE improved the neurological condition through enhanced neuronal functions of the remaining neurons in the damaged areas rather than by maintaining neuronal survival. These results suggest that DAEE has a neuro-protective effect on cerebral infarction

Exploring the association between number of teeth, food intake, and cognitive function: A 9-year longitudinal study

Mameno T., Moynihan P., Nakagawa T., et al. Exploring the association between number of teeth, food intake, and cognitive function: A 9-year longitudinal study. Journal of Dentistry 145, 104991 (2024); https://doi.org/10.1016/j.jdent.2024.104991.Objectives: This study aimed to investigate the association between the number of teeth, food intake, and cognitive function in Japanese community-dwelling older adults. Methods: This 9-year longitudinal study included a total of 293 analyzable participants who participated in baseline and follow-up surveys. Dental status (number of teeth and periodontal pocket depth), dietary assessment using the brief-type self-administered diet history questionnaire, cognitive function, and the following confounding factors were evaluated: educational level, financial satisfaction, living situation, smoking and drinking habits, history of chronic diseases, apolipoprotein E-ε4 carrier, body mass index, handgrip strength, instrumental activities of daily living, and depressive symptomatology. The Japanese version of the Montreal Cognitive Assessment was used to evaluate cognitive function. A multinomial logistic regression analysis for the intake level of each food categorized into three groups (low, moderate, high), and a generalized estimating equation (GEE) for cognitive function over nine years were performed. Results: After controlling for confounding factors, the number of teeth was shown to be associated with the intake of green-yellow vegetables and meat. Furthermore, the GEE indicated that the lowest quartile of intake of green-yellow vegetables significantly associated with lower cognitive function (unstandardized regression coefficient [B] = -0.96, 95 % confidence interval [CI]: -1.72 to -0.20), and the lowest quartile of intake of meat significantly associated with lower cognitive function (B = -1.42, 95 % CI: -2.27 to -0.58). Conclusions: The intake of green and yellow vegetables and meat, which is influenced by the number of teeth, was associated with cognitive function in Japanese community-dwelling older adults. Clinical Significance: There are few studies that have examined the association between oral health, food intake, and cognitive function. This 9-year longitudinal study suggests that it is important to maintain natural teeth to enable the functional means to consume green-yellow vegetables and meat, and thereby help maintain cognitive function

Changes in Atrial Size Following PVI: Comparison of the Right and Left Atria

Background: Pulmonary vein isolation (PVI) is expected to cure atrial fibrillation (AF) and to improve atrial remodeling. However, the effects of PVI on the right atrial (RA) size have not been fully examined. We studied the effects of PVI on RA size in comparison that with the effects on LA size. Method: We studied 17 patients with drug-refractory AF (11 paroxysmal, 6 persistent). Two-dimensional echocardiography was performed at baseline and at follow-up to measure and compare RA and LA size.Results: Despite a short duration of AF in 7 patients after the PVI, all cases were maintained in sinus rhythm during the follow-up. LA and RA size were both reduced after the PVI compared with baseline measurements (LA 25.5 ± 2.9cm2 vs. 23.2 ± 3.6cm2, P < 0.05, RA 21.2 ± 2.9cm2 vs. 18.1 ± 3.0cm2, P < 0.01). The reduction ratio was more prominent in RA size (14.9%) than in LA size (8.7%)(P < 0.05). Conclusion: Atrial size was reduced following PVI for both the LA and RA, although the rate of reduction was more prominent in the RA

DAMP-Inducing Adjuvant and PAMP Adjuvants Parallelly Enhance Protective Type-2 and Type-1 Immune Responses to Influenza Split Vaccination

Recently, it was reported that 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD), a common pharmaceutical additive, can act as a vaccine adjuvant to enhance protective type-2 immunogenicity to co-administered seasonal influenza split vaccine by inducing host-derived damage-associated molecular patterns (DAMPs). However, like most other DAMP-inducing adjuvants such as aluminum hydroxide (Alum), HP-β-CyD may not be sufficient for the induction of protective type-1 (cellular) immune responses, thereby leaving room for improvement. Here, we demonstrate that a combination of HP-β-CyD with a humanized TLR9 agonist, K3 CpG-ODN, a potent pathogen-associated molecular pattern (PAMP), enhanced the protective efficacy of the co-administered influenza split vaccine by inducing antigen-specific type-2 and type-1 immune responses, respectively. Moreover, substantial antigen-specific IgE induction by HP-β-CyD, which can cause an allergic response to immunized antigen was completely suppressed by the addition of K3 CpG-ODN. Furthermore, HP-β-CyD- and K3 CpG-ODN-adjuvanted influenza split vaccination protected the mice against lethal challenge with high doses of heterologous influenza virus, which could not be protected against by single adjuvant vaccines. Further experiments using gene deficient mice revealed the unique immunological mechanism of action in vivo, where type-2 and type-1 immune responses enhanced by the combined adjuvants were dependent on TBK1 and TLR9, respectively, indicating their parallel signaling pathways. Finally, the analysis of immune responses in the draining lymph node suggested that HP-β-CyD promotes the uptake of K3 CpG-ODN by plasmacytoid dendritic cells and B cells, which may contributes to the activation of these cells and enhanced production of IgG2c. Taken together, the results above may offer potential clinical applications for the combination of DAMP-inducing adjuvant and PAMP adjuvant to improve vaccine immunogenicity and efficacy by enhancing both type-2 and type-1 immune responses in a parallel manner