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Atsushi Nakayama Motohiko Kato Yusaku Takatori Masayuki Shimoda Mari Mizutani Koshiro Tsutsumi Yoshiyuki Kiguchi Teppei Akimoto Motoki Sasaki Makoto Mutaguchi Kaoru Takabayashi Tadateru Maehata Yasutoshi Ochiai Takanori Kanai Naohisa Yahagi 《Digestive endoscopy》2020,32(3):417-424
There are no reports on detailed endoscopic diagnosis of superficial non-ampullary duodenal epithelial tumors (SNADET) except for relatively small case series. Herein, we conducted a prospective observational study to investigate the relationship between endoscopic findings and histopathological diagnosis of SNADET. A total of 163 SNADET diagnosed using magnified endoscopic examination with image-enhanced endoscopy (IEE-ME) were prospectively registered in this study. We investigated location, size, macroscopic type, color, and IEE-ME findings including surface structure (closed- or open-loop) and presence of white opaque substance (WOS) in SNADET. We analyzed association between these findings and histopathological diagnosis of SNADET based on the Vienna classification (VCL) using logistic regression analysis. In univariate analysis, lesion size, superficial structure, and WOS deposition showed statistical significance, and the oral side of the lesion location showed statistical tendency for association with VCL C4/5. In multivariate analysis, lesion size (odds ratio [OR], 2.92; 95% CI, 1.94–4.39; P < 0.05) and negative WOS (OR, 5.59; 95% CI, 1.72–18.1; P < 0.05) were significantly associated with VCL C4/5 lesions. Superficial structures with a closed-loop pattern on the surface showed statistical tendency for predicting VCL C4/5 lesions (OR, 2.15; 95% CI, 0.86–5.37; P = 0.10). Based on these findings, we concluded that negative WOS by IEE-ME and lesion size were independent predictors of VCL C4/5 SNADET. These factors may help us to understand of pathophysiology of SNADET and to select appropriate therapeutic strategies. 相似文献
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Hiroko Kobayashi Ryo Suzuki Kei Sato Takatoshi Ogami Hiroshi Tomozawa Masahito Tsubata Koji Ichinose Masaki Aburada Wataru Ochiai Kiyoshi Sugiyama Tsutomu Shimada 《Journal of natural medicines》2018,72(1):136-144
Knee osteoarthritis (OA) is becoming more prevalent worldwide due to increases in the numbers of elderly and obese patients. Currently, pharmaceutical medicines used for the treatment of OA are for symptomatic therapy and therefore new therapeutic agents are needed. Kaempferia parviflora (KP) is a plant growing naturally in Southeast Asia and has various pharmacological effects including an anti-inflammatory effect, but no effect on OA has yet been reported. We therefore conducted a search for the effects KP and the active components of KP extract (KPE) exert on OA as well as its mechanism of action. Results from a study of KPE using the monoiodoacetic acid rat OA model revealed that KPE reduced the pain threshold and severity of osteoarthritic cartilage lesions. The mechanism of action and active components were then investigated using IL-1β-treated human knee-derived chondrocytes. KPE, as well as 5,7-dimethoxyflavone and 5,7,4′-trimethoxyflavone, which are key constituents of KPE and highly absorbable into the body, reduced the expression of matrix metalloproteinases (MMPs), which are the main extracellular matrix enzymes that degrade collagen within cartilage. As mentioned above, KPE acted to suppress OA and 5,7-dimethoxyflavone and 5,7,4′-trimethoxyflavone were shown to be involved as part of KPE’s mechanism that inhibits MMPs. 相似文献
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Rie Matsunaga Motohiro Kojima Yuji Nishizawa Mitsuru Yokota Hiro Hasegawa Norio Saito Masaaki Ito Atsushi Ochiai 《Pathology international》2019,69(5):272-281
The pathological assessment of the resection margin of rectal cancer is important to predict clinical outcome. The transverse slicing method of rectal specimens is recommended in Western countries. However, in Japan the longitudinal slicing method is traditionally advocated. The aim of this study was to assess the advantages of the longitudinal slicing method. The subjects were 197 consecutive patients with primary rectal cancer who underwent curative intersphincteric resection from 2000 to 2013. The resected rectal specimens were cut into 12 slices in the direction of the long axis. Resection margin was considered positive when it was less than or equal to 1 mm. Resection margin was positive in 23 patients (12%). They were classified into two groups, namely the DEEP group (n = 16, 70%), when the resection margin corresponded to the deepest tumor invasion area, and the ENTRY group (n = 7, 30%), when resection margin was around the initial cutting point of the anal canal. It was shown that resection margin tends to be positive not only in the deepest tumor invasion area but also in the entry area of the anal canal. The longitudinal slicing method may have some advantages for accurate assessment of resection margin especially in low‐lying rectal cancer. 相似文献
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Four hybrid cell lines secreting monoclonal antibodies (McAbs) against glucosyltransferase synthesizing water-insoluble glucan (GTase-I) were generated by fusion of myeloma cells (P3U1) with splenocytes from mice immunized with GTase-I from Streptococcus sobrinus B13-N. Cell lines 29E7, 21GC7, and 42HB8 were found to secrete an IgG2a-type immunoglobulin, and 29EG, an IgM-type immunoglobulin. These two isotypes of McAbs were used for the determination of the binding sites on the GTase molecule, with use of an enzyme-linked immunosorbent assay. The binding site for McAb 29EG was different from the site that bound other McAbs. McAb 29EG was found to inhibit water-insoluble glucan synthesis by GTase-I by 50%, and 29E7 was found to inhibit it weakly. However, other McAbs did not show any inhibitory effect in spite of binding to GTase-I. McAb 42HB8 strongly inhibited GTase-I-mediated adherence of heat-killed cells of S. sobrinus B-13N to glass surfaces. When the McAbs were tested for their cross-reactivity among GTase preparations from different mutans streptococci, McAb 29EG reacted with S. cricetus and S. sobrinus, but not with other mutans streptococci. Three other McAbs, 21GC7, 29E7, and 42HB8, were found to react only with the enzyme from S. sobrinus. These findings indicated that the specificity of the McAbs studied varied with respect to the antigenic sites on the GTase-I molecule, and that some of the sites differed in their functions. 相似文献
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Kurita-Ochiai T Seto S Suzuki N Yamamoto M Otsuka K Abe K Ochiai K 《Journal of dental research》2008,87(1):51-55
Butyric acid, an extracellular metabolite from periodontopathic bacteria, induces apoptosis in murine and human T- and B-cells, whereas intact gingival fibroblasts isolated from healthy humans are resistant to butyric-acid-induced apoptosis. We examined the susceptibility of inflamed gingival fibroblasts isolated from adult persons with periodontitis to butyric-acid-induced apoptosis. Butyric acid significantly suppressed the viability of inflamed gingival fibroblasts and induced apoptosis in a dose-dependent manner. The incubation of inflamed gingival fibroblasts with butyric acid induced DNA fragmentation and apoptotic changes such as chromatin condensation, hypodiploid nuclei, and mitochondrial injury. Furthermore, butyric-acid-induced apoptosis in inflamed gingival fibroblasts was reduced by caspase-3/7, -6, -8, and -9 inhibitors. Thus, inflamed gingival fibroblasts from adult persons with periodontitis appear to be highly susceptible to mitochondria- and caspase-dependent apoptosis induced by butyric acid, compared with healthy gingival fibroblasts. 相似文献
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STATEMENT OF PROBLEM: The inhibitory effect of indirect latex contamination on the polymerization of vinyl polysiloxane (VPS) impression material has been previously reported. However, the transfer of specific elements that cause inhibition has not been confirmed, nor has the removal of such contaminants been reported. PURPOSE: This study examined the surfaces of materials commonly used in restorative procedures that were contaminated by indirect latex glove contact and then evaluated for inhibition of polymerization of VPS. The effect of selected cleansing procedures was then studied. MATERIAL AND METHODS: Four experimental groups (n = 8) were prepared: (1) clean vinyl gloves (control), (2) clean gingival retraction cords (control), (3) contaminated vinyl gloves, and (4) contaminated gingival retraction cord. Microscopic evaluation of the appearance and the characterization of surface particulate contamination were performed for each. Three cleansing protocols were then evaluated for efficacy in cleaning vinyl glove surfaces contaminated by latex contact (n = 10): (1) brushing with water, (2) brushing with soap/rinsing with water, (3) cleansing with rubbing alcohol. The subsequent degree of VPS polymerization inhibition was evaluated subjectively. A chi-square test was used for data analysis (alpha=.05). RESULTS: Particulate sulfur elements and sulfur-chloride compounds were present on the contaminated substrates. None of the 3 cleansing procedures eliminated polymerization inhibition (P =.33). Residual elemental sulfur remained on all tested surfaces. CONCLUSION: Particulate sulfur and sulfur-chloride compounds were identified as the particulate contamination that resulted in polymerization inhibition of the tested VPS dental impression material. Removal of these contaminants from the tested vinyl gloves and gingival retraction cord was not possible with the 3 cleansing protocols tested in this study. 相似文献
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