Gradients in periodontal status in Japanese employed males

AIM: The objective was to assess whether there was a social gradient in periodontal status by job classification in Japanese male workers. MATERIAL AND METHODS: Study participants were 15,803 Japanese male workers aged 20-69 years. There were seven groups classified by jobs. Oral examinations were conducted using community periodontal index (CPI). RESULTS: The percentages of sextants with a CPI score of 3 or 4 of professionals were significantly lower than for other job classes. The gradient also existed for the percentage of sextants with CPI score 4. After adjusting for age, a history of diabetes mellitus and smoking status, those lower on the gradient, namely, drivers, service occupations, salespersons and managers were 2.0, 1.5, 1.4 and 1.4, times, respectively more likely to have one or more sextants with CPI score 3 or 4 compared with professionals. Odds ratios of having more than one or more sextants with CPI score 4 after adjusting for age, clinical history of diabetes mellitus and smoking status for drivers, service occupations, salespersons and managers were 2.1, 1.5, 1.5 and 1.2, respectively, compared with professionals. CONCLUSIONS: There was a gradient in periodontal status by job classification. Professional and office workers had better periodontal status than salespersons, service occupations and drivers.     

Social nicotine dependence in Australian dental undergraduate students

Objectives: This study aimed to investigate dental undergraduate students’ tobacco usage and social nicotine dependence in Australia. A special interest was to identify the role of factors such as age, gender, year of dental education and cohabitants’ smoking status for social nicotine dependence. Materials and methods: A sample of 252, first‐to‐fifth year undergraduate students in an Australian dental school was used. Each completed a self‐administered questionnaire. Results: The smoking rate was 4.8%. Current smokers displayed higher social nicotine dependence than those that had never smoked (t = 3.1, df = 244, P = 0.002). Dental undergraduate students that showed higher social nicotine dependence (P = 0.001, OR = 1.3, 95% CI: 1.1–1.6), or that had smoking cohabitants (P = 0.016, OR = 4.8, 95% CI: 1.3–17.0), were more likely to smoke. Students’ social nicotine dependence increased with year of dental study (P = 0.043, β = 0.4, t = 2.0). Social nicotine dependence enhanced tobacco usage among Year‐1‐to‐4 students (P = 0.005, OR = 1.4, 95% CI: 1.1–1.7) but not Year‐5 undergraduates (P = 0.432). Conclusions: Social nicotine dependence has become a developing issue in dental education. Tobacco control should be highlighted in the dental curriculum. Future investigations into the effects of dental education on social nocotine dependence and tobacco usage are indicated.     

Site specific mineral composition and microstructure of human supra-gingival dental calculus

Dental calculus has been implicated in the aetiology of several periodontal conditions. Its prevention and removal are therefore desirable clinical goals. While it is known that calculus is very variable in chemical composition, crystallinity and crystallite size little is known about site specific variability within a dentition and between individuals. With this in mind, a study was undertaken to investigate the comparative site specific nature and composition of human dental supra-gingival dental calculus obtained from 66 male patients visiting for their dental check-up using fluorescent X-ray spectroscopy, X-ray diffractometry and Fourier transform infrared spectroscopy. The supra-gingival dental calculus formed on the lingual surfaces of lower anterior teeth and the buccal surfaces of upper molar teeth were classified into four types based on calcium phosphate phases present. There was significant difference in composition of the crystal phase types between lower and upper teeth (p<0.01). There was no significant difference in crystal size between dental calculus on anterior or molar teeth of all samples. The degree of crystallinity of dental calculus formed on the upper molar teeth was higher than that formed on the lower anterior teeth (p<0.01). The CO(3)(2-) contents in dental calculus formed on the lower anterior teeth were higher than on upper molar teeth (p<0.05) which might explain the difference in crystallinity. Magnesium and Si contents and Ca:P ratio on the other hand showed no significant difference between lower and upper teeth. It was concluded that the crystal phases, crystallinity and CO(3)(2-) contents of human dental supra-gingival dental calculus is related to its location in the mouth.     

Cell‐type‐dependent action potentials and voltage‐gated currents in mouse fungiform taste buds

Taste receptor cells fire action potentials in response to taste substances to trigger non‐exocytotic neurotransmitter release in type II cells and exocytotic release in type III cells. We investigated possible differences between these action potentials fired by mouse taste receptor cells using in situ whole‐cell recordings, and subsequently we identified their cell types immunologically with cell‐type markers, an IP₃ receptor (IP₃R3) for type II cells and a SNARE protein (SNAP‐25) for type III cells. Cells not immunoreactive to these antibodies were examined as non‐IRCs. Here, we show that type II cells and type III cells fire action potentials using different ionic mechanisms, and that non‐IRCs also fire action potentials with either of the ionic mechanisms. The width of action potentials was significantly narrower and their afterhyperpolarization was deeper in type III cells than in type II cells. Na⁺ current density was similar in type II cells and type III cells, but it was significantly smaller in non‐IRCs than in the others. Although outwardly rectifying current density was similar between type II cells and type III cells, tetraethylammonium (TEA) preferentially suppressed the density in type III cells and the majority of non‐IRCs. Our mathematical model revealed that the shape of action potentials depended on the ratio of TEA‐sensitive current density and TEA‐insensitive current one. The action potentials of type II cells and type III cells under physiological conditions are discussed.     

Involvement of Nax sodium channel in peripheral nerve regeneration via lactate signaling

Na_x, a sodium concentration‐sensitive sodium channel, is expressed in non‐myelinating Schwann cells of the adult peripheral nervous system, but the pathophysiological role remains unclear. We found that functional recovery of the hind paw responses from the sciatic nerve transection was delayed in Na_x knockout ( ) mice. Histological analyses showed a decrease in the number of regenerated myelinated axons in sciatic nerves. The delay in the recovery in mice was improved by lactate and inhibited by a monocarboxylate transporter inhibitor. In vitro experiments using cultured Schwann cells showed that lactate release was enhanced by endothelin (ET)‐1 and blocked by an ET receptor type B antagonist. Here, it is conceivable that Na_x was activated by ET‐1. The amount of lactate release by ET‐1 was lower in mice than in wild‐type mice. These results indicated that Na_x is functionally coupled to ET for lactate release via ET receptor type B and is involved in peripheral nerve regeneration.     

Once-Weekly Injection of Low-Dose Teriparatide (28.2 μg) Reduced the Risk of Vertebral Fracture in Patients with Primary Osteoporosis

We conducted a randomized, double-blind trial to assess the effect of 28.2 μg teriparatide versus placebo (1.4 μg teriparatide) on reduction of the incidence of vertebral fractures. Individuals enrolled in this study included patients with primary osteoporosis with one to five vertebral fractures and capable of self-supported walking. Attention was focused on incident vertebral fractures, change in bone mineral density (BMD) of the lumbar spine, and safety. A total of 316 subjects participated in the study, which lasted up to 131 weeks. Incident vertebral fractures occurred in 3.3 % of subjects in the 28.2 μg teriparatide-treated group and 12.6 % of subjects in the placebo group during the 78-weeks study period. Kaplan–Meier estimates of risk after 78 weeks were 7.5 and 22.2 % in the teriparatide and placebo groups, respectively, with a relative risk reduction of 66.4 % by teriparatide (P = 0.008). Lumbar BMD in the 28.2 μg teriparatide group increased significantly by 4.4 ± 4.7 % at 78 weeks, which was significantly higher than the corresponding data in the placebo group (P = 0.001). Adverse events were observed in 86.7 % of individuals in the teriparatide group and 86.1 % of those in the placebo group. In conclusion, weekly injection of a low-dose of teriparatide (28.2 μg) reduced the risk of incident vertebral fractures and increased lumbar BMD.     

Management of Early-stage Esophageal Neoplasia (MESEN) Consensus

Background

Treatment of esophageal adenocarcinoma often involves surgical resection. Newer technologies in interventional endoscopy have led to a substantial paradigm shift in the management of early-stage neoplasia in Barrett’s esophagus comprising high-grade dysplasia (HGD), intramucosal carcinoma, and, in some cases, submucosal carcinoma. However, there has been no consensus regarding the indications for esophageal preservation in these cases. In this work, consensus guidelines were established for the management of early-stage esophageal neoplasia considering clinically relevant aspects (age, comorbidities, and social environment) in each scenario.

Methods

Seventeen experts were invited to participate based on their background and clinical expertise at high-volume centers. A questionnaire was created that included four clinical scenarios covering a wide range of situations within HGD and/or early esophageal neoplasia, particularly where controversies are likely to exist. Each of the clinical scenarios was open to discussion subdivided by patient age (20, 50, and 80 s). For each clinical scenario an expert was chosen to defend that position. Each defense triggered a subsequent discussion during a consensus meeting. Conclusions of that discussion together with an accompanying literature analysis allowed experts to confirm or change their original choices and served as the basis for the recommendations stated in this article.

Results

There was 100 % consensus supporting esophageal preservation in patients with HGD, independent of patient age or Barrett’s length. In patients with T1a adenocarcinoma, consensus for preservation was not reached (65 %) for young and middle-aged individuals but was supported for elderly patients (100 %). For T1b adenocarcinoma, consensus was reached for surgical resection (90 %), leaving organ preservation for patients with very low risk of nodal invasion or poor surgical candidates.

Conclusion

Advances in endoscopic imaging and therapy allow for organ preservation in most settings of early-stage neoplasia of the esophagus, provided that the patient understands the implications of this decision.