A static characteristic analysis of proposed bi-directional dual active bridge DC-DC converter

Recently, the power supply network with energy storage devices such as battery has been focused. This network topology uses bi-directional isolated DC-DC converter of low or medium capacity is required for the diversification of power supply network. The dual active bridge (DAB) DC-DC converter is one of the effective bi-directional isolated DC-DC converters. However, the circuit has some instinct problems such as degradation of power efficiency and the occurrence of the surge in light-load operation. In this paper, we have been done a static characteristic analysis and highly power-efficient technique for DAB DC-DC Converter at light load. Also the analysis results and the proposed technique are verified with some experimental results.7th International Power Electronics Conference, IPEC-Hiroshima - ECCE Asia 2014; Hiroshima; Japan; 18 May 2014 through 21 May 201

Gan-Lu-Yin (Kanroin), Traditional Chinese Herbal Extracts, Reduces Osteoclast Differentiation In Vitro and Prevents Alveolar Bone Resorption in Rat Experimental Periodontitis

Gan-Lu-Yin (GLY), a traditional Chinese herbal medicine, shows therapeutic effects on periodontitis, but that mechanism is not well known. This study aims to clarify the precise mechanism by investigating the inhibitory effects of GLY extracts on osteoclastogenesis in vitro and on bone resorption in periodontitis in vivo. RAW264.7 cells are cultured with soluble receptor activator of nuclear factor-kappa B (sRANKL) and GLY extracts (0.01–1.0 mg/mL), and stained for tartrate-resistant acid phosphatase (TRAP) to evaluate osteoclast differentiation. Experimental periodontitis is induced by placing a nylon ligature around the second maxillary molar in rats, and rats are administered GLY extracts (60 mg/kg) daily for 20 days. Their maxillae are collected on day 4 and 20, and the levels of alveolar bone resorption and osteoclast differentiation are estimated using micro-computed tomography (CT) and histological analysis, respectively. In RAW264.7 cells, GLY extracts significantly inhibit sRANKL-induced osteoclast differentiation at a concentration of more than 0.05 mg/mL. In experimental periodontitis, administering GLY extracts significantly decreases the number of TRAP-positive osteoclasts in the alveolar bone on day 4, and significantly inhibits the ligature-induced bone resorption on day 20. These results show that GLY extracts suppress bone resorption by inhibiting osteoclast differentiation in experimental periodontitis, suggesting that GLY extracts are potentially useful for oral care in periodontitis

Glycated Albumin in Gingival Crevicular Fluid from Patients With Diabetes

Background: Diabetes mellitus (DM) patients have a high prevalence of periodontitis. DM-associated periodontitis (DM-P) is characterized by severe inflammation and tissue destruction. To diagnose DM-P is important for cures of periodontitis and DM. The purpose of this study was to investigate the levels of glycated albumin (GA), a DM marker, and calprotectin, an inflammatory marker, in gingival crevicular fluid (GCF) from patients with periodontitis and DM. Methods: Seventy-eight subjects participated in this study were the patients with DM, chronic periodontitis (CP), DM-P and healthy individuals (H). GCF and blood were collected from four groups. GA and calprotectin in GCF were analyzed using western blotting and ELISA, and their levels were compared among H, DM, CP, and DM-P groups. GA and glycated hemoglobin (HbA1c) in blood were determined, and the correlation between GCF GA level and blood HbA1c or GA level was investigated. ROC analysis for GCF GA level to predict DM was performed. Results: GA was identified in GCF, and its amount and concentration in GCF samples from DM and DM-P were significantly higher than those of non-DM groups (H and CP). Calprotectin amount in GCF from CP and DM-P was significantly higher than that in H and DM groups. GCF GA level was positively correlated to blood HbA1c and GA level. ROC analysis of GCF GA level showed an optimal cut-off value to predict DM. Conclusions: GA showed a high level in GCF from DM patients. GA and calprotectin in GCF may be useful markers to diagnose DM-associated periodontitis

Elastic fiber assembly is disrupted by excessive accumulation of chondroitin sulfate in the human dermal fibrotic disease, keloid

Keloid is a fibrotic disease characterized by abnormal accumulation of extracellular matrix in the dermis. The keloid matrix contains excess collagen and glycosaminoglycans (GAGs), but lacks elastic fiber. However, the roles of these matrix components in the pathogenesis of keloid are largely unknown. Here, we show that elastin and DANCE (also known as fibulin-5), a protein required for elastic fiber formation, are not deposited in the extracellular matrix of keloids, due to excess accumulation of chondoitin sulfate (CS), although the expression of elastin and DANCE is not affected. Amount of CS accumulated in the keloid legion was 6.9-fold higher than in normal skin. Fibrillin-1, a scaffold protein for elastic fiber assembly, was abnormally distributed in the keloid matrix. Addition of purified CS to keloid fibroblast culture resulted in abnormal deposition of fibrillin-1, concomitant with significantly decreased accumulation of elastin and DANCE in the extracellular matrix. We propose that CS plays a crucial role in the development of keloid lesions through inhibition of elastic fiber assembly

Cognitive and Emotional Changes in Peer Educators of Type 2 Diabetes Patients After Starting Peer-Support Activities

Background: Diabetes self-management education through peer support has beneficial effects, especially in regions with limited medical resources. To ensure peer educators continue to provide peer-led education programs, it is important that they remain motivated to instruct patients. Here, to explore measures to enhance peer-educators’ motivation toward such programs, we examined the cognitive and emotional changes in Filipino type 2 diabetics after 7-month activities as peer educators. Methods: We individually performed semi-structured interviews with 13 peer educators with 20 years of age or above in August 2017 (immediately before starting their peer-education activities) and in March 2018 (7 months after the start). The first interview was performed after the peer educators had received 2-day training of diabetes self-management. In both interviews, we asked the peer educators about their feelings toward peer-led educational activities (e.g., satisfaction, difficulty, reward, confidence, and challenges). Their replies about their own cognition and emotions were interpreted and integrated, and then analyzed qualitatively. Results: Four and seven categories were extracted from the first and second interviews, respectively. The category “Cognition of patients’ active learning attitudes and of positive changes in patients’ physical conditions and behavior” observed in the second interview led to “Cognition of growth as a peer educator” and “Satisfaction with supporting patients as a peer educator.” These two feelings gave the peer educators’ “Increased motivation to continue the activities as a peer educator.” This motivation was also associated with “Active collaboration among peer educators,” which was affected by “Difficulties and concerns in working as a peer educator.” Conclusion: To sustain diabetic peer-led education programs, we suggest that interventions be implemented that increase peer educators’ motivation toward their activities and stimulate their awareness of the importance of collaborating with one another. Such collaboration should help to overcome the difficulties they may face in providing peer-led education

Association between periodontal condition and kidney dysfunction in Japanese adults : A cross‐sectional study

Recent studies have demonstrated that chronic kidney disease (CKD) may be associated with the progression of periodontal disease. Diabetes mellitus (DM) is a major risk factor for CKD. The objective of this study was to clarify the relationship between periodontal condition and kidney dysfunction in patients who had kidney failure with or without DM. One hundred sixty‐four patients with kidney dysfunction were enrolled (male: N = 105; female: N = 59), and the relationship between periodontal condition and kidney dysfunction was analyzed in a cross‐sectional study. The subjects were divided into three groups: (a) patients with DM, (b) dialysis patients with nephropathy due to various kidney diseases, and (c) dialysis patient with nephropathy due to DM (diabetic nephropathy). Then, the effect of DM on the periodontal condition was analyzed. The patients were also stratified by CKD stage (into G1–G5) using the estimated glomerular filtration rate (eGFR), and the G5 group was divided in patients with or without DM. Correlations between eGFR and parameters of periodontal condition were calculated in patients from G1 to G4. The number of missing teeth was significantly higher in dialysis patients with diabetic nephropathy than in patients with DM, whereas alveolar bone loss did not show a significant difference among the three groups. In addition, the G5 patients with DM had a significantly higher number of missing teeth than the other CKD groups, whereas alveolar bone loss did not show a significant difference. In G5 patients with DM, Community Periodontal Index and Oral Hygiene Index scores were significantly higher than in G1‐4 patients with DM. There was a significant negative correlation between eGFR and the number of missing teeth. Patients with diabetic nephropathy have a higher rate of periodontal problems such as missing teeth in Japanese adults

AGEs increase IL-6 and ICAM-1 expression

Background and Objectives: Diabetes mellitus (DM) is a risk factor for periodontal diseases and may exacerbate the progression of the pathogenesis of periodontitis. Advanced glycation end-products (AGEs) cause DM complications relative to levels of glycemic control and larger amounts accumulate in the periodontal tissues of patients with periodontitis and DM. In the present study, we investigated the effects of AGEs on the expression of inflammation-related factors in human gingival fibroblasts (HGFs) in order to elucidate the impact of AGEs on DM-associated periodontitis. Materials and Methods: HGFs were cultured with or without AGEs. Cell viability was examined, and RNA and protein fractions were isolated from AGE-treated cells. The expression of IL-6, ICAM-1, and the receptor for AGE (RAGE) was investigated using RT-PCR, quantitative real-time PCR, and ELISA, and reactive oxygen species (ROS) activity was measured using a kit with 2’,7’-dichlorofluorescin diacetate. Human monocytic cells (THP-1) labelled with a fluorescent reagent were co-cultured with HGFs treated with AGEs and IL-6 siRNA, and the adhesive activity of THP-1 cells to HGFs was assessed. The expression of IL-6 and ICAM-1 was examined when HGFs were pretreated with recombinant human IL-6 (rhIL-6), the siRNAs of RAGE and IL-6, and inhibitors of MAPK and NF-κB, and then cultured with and without AGEs. The phosphorylation of MAPK and NF-κB was assessed using Western blotting. Results: AGEs increased the mRNA and protein expressions of RAGE, IL-6, ICAM-1 and ROS activity in HGFs, and promoted the adhesion of THP-1 cells to HGFs, but had no effect on cell viability until 72 h. rhIL-6 increased ICAM-1 expression in HGFs, while the siRNAs of RAGE and IL-6 inhibited AGE-induced IL6 and ICAM1 mRNA expression, and IL-6 siRNA depressed AGE-induced THP-1 cell adhesion. AGEs increased the phosphorylation of p38 and ERK MAPKs, p65 NF-κB, and IκBα, while inhibitors of p38, ERK MAPKs, and NF-κB significantly decreased AGE-induced IL-6 and ICAM-1 expression. Conclusions: AGEs increase IL-6 and ICAM-1 expression via the RAGE, MAPK and NF-κB pathways in HGFs and may exacerbate the progression of the pathogenesis of periodontal diseases

β-defensin-1 SNPs in Japanese periodontitis

Background and Objective: Periodontitis is a multifactorial disease associated with genetic and environmental factors. Recent reports have shown that single-nucleotide polymorphisms (SNPs) are associated with susceptibility to common diseases such as not only diabetes and hypertension but also periodontitis. Although the oral cavity is continuously exposed to various pathogenic organisms, the oral conditions are well controlled by innate and acquired immune systems. Antimicrobial peptides (AMPs) play an important role in the innate immune system; however, the association of AMP-SNPs with periodontitis has not been fully elucidated. The aim of the present study was to investigate the relationship between AMP-SNPs and periodontitis in Japanese. Methods: One hundred and five Japanese subjects were recruited, which included 21 patients with aggressive, 28 with severe, 13 with moderate and 22 with mild periodontitis, as well as 21 age-matched healthy controls. Genomic DNA was isolated from peripheral blood in each subject. Genotypes of four reported SNPs of β-defensin-1 and lactoferrin genes (DEFB1: rs1799946, rs1800972 and rs11362; and LTF: rs1126478) were investigated using the PCR-Invader assay. Protein levels of AMP in gingival crevicular fluid (GCF) were quantified by ELISA. Results: Case-control studies revealed that the -44 CC genotype of DEFB1 (rs1800972) was associated with severe chronic periodontitis (odds ratio 4.15) and with combined severe and moderate chronic periodontitis (odds ratio 4.04). No statistical differences were found in other genotypes. The β-defensin-1 concentrations in GCF were significantly lower in the subjects with the -44 CC genotype of DEFB1 than in those without this genotype. No significant differences between GCF concentrations of AMPs and other genotypes were detected. Conclusion: The -44 CC genotype of the β-defensin-1 gene (DEFB1 rs1800972) may be associated with susceptibility to chronic periodontitis in Japanese