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941.
Fumiaki Ono Takumi Okihara Noboru Osaka Noriyuki Nagaoka Yuji Kameoka Akira Ishikawa Hironari Ooki Takumi Ito Daisuke Todome Shinya Uemoto Mitsuaki Furutani Tsutomu Inokuchi Kenji Okada 《RSC advances》2022,12(6):3300
Nitrogen/phosphorus-containing melamines (NPCM), a durable flame-retardant, were prepared by the successive treatment of ArOH (Ar = BrnC6H5−n, n = 0, 1, 2, and 3) with POCl3 and melamine monomer. The prepared flame-retardants were grafted through the CH2 unit to lignocellulose nanofibers (LCNFs) by the Mannich reaction. The resulting three-component products were characterized using FT-IR (ATR) and EA. The thermal behavior of the NPCM-treated LCNF fabric samples was determined using TGA and DSC analyses, and their flammability resistances were evaluated by measuring their Limited Oxygen Index (LOI) and the UL-94V test. A multitude of flame retardant elements in the fabric samples increased the LOI values as much as 45 from 20 of the untreated LCNFs. Moreover, the morphology of both the NPCM-treated LCNFs and their burnt fabrics was studied with a scanning electron microscope (SEM). The heat release lowering effect of the LCNF fabric against the water-based paint was observed with a cone calorimeter. Furthermore, the mechanical properties represented as the tensile strength of the NPCM-treated LCNF fabrics revealed that the increase of the NPCM content in the PP-composites led to an increased bending strength with enhancing the flame-retardance.LCNFs were grafted with nitrogen/phosphorus-containing melamines to achieve potent flame-retardance and converted to PP-composites of improved mechanical properties. 相似文献
942.
Kota Ouchi Shin Takahashi Akira Okita Yasuhiro Sakamoto Osamu Muto Kenji Amagai Takaho Okada Hisatsugu Ohori Eiji Shinozaki Chikashi Ishioka 《Cancer science》2022,113(3):1057
DNA methylation status correlates with clinical outcomes of anti‐epidermal growth factor receptor (EGFR) treatment. There is a strong need to develop a simple assay for measuring DNA methylation status for the clinical application of drug selection based on it. In this study, we collected data from 186 patients with metastatic colorectal cancer (mCRC) who had previously received anti‐EGFR treatment. We modified MethyLite to develop a novel assay to classify patients as having highly methylated colorectal cancer (HMCC) or low‐methylated colorectal cancer (LMCC) based on the methylation status of 16 CpG sites of tumor‐derived genomic DNA in the development cohort (n = 30). Clinical outcomes were then compared between the HMCC and LMCC groups in the validation cohort (n = 156). The results showed that HMCC had a significantly worse response rate (4.2% vs 33.3%; P = .004), progression‐free survival (median: 2.5 vs 6.6 mo, P < .001, hazard ratio [HR] = 0.22), and overall survival (median: 5.6 vs 15.5 mo, P < .001, HR = 0.23) than did LMCC in patients with RAS wild‐type mCRC who were refractory or intolerable to oxaliplatin‐ and irinotecan‐based chemotherapy (n = 101). The DNA methylation status was an independent predictive factor and a more accurate biomarker than was the primary site of anti‐EGFR treatment. In conclusion, our novel DNA methylation measurement assay based on MethyLight was simple and useful, suggesting its implementation as a complementary diagnostic tool in a clinical setting. 相似文献
943.
Akira Fujimori Hirokazu Hirakawa Cuihua Liu Taishin Akiyama Bevin P Engelward Jac A Nickoloff Masao Suzuki Bing Wang Mitsuru Nenoi Sei Sai 《American journal of cancer research》2022,12(2):562
In this study, we aimed to investigate how homologous recombinant (HR)-related genomic instability is involved in ionizing radiation (IR)-induced thymic lymphoma in mice. We divided five-week-old Rosa26 Direct Repeat-GFP (RaDR-GFP) transgenic mice into non-IR control and IR groups and exposed the mice in the IR group to a 7.2 Gy dose of γ-rays, delivered in 1.8 Gy fractions, once a week for four weeks. We then estimated mouse survival and recorded their body, thymus, and spleen weights. The frequency of HR events in the chromosomes of the thymus, bone marrow, and spleen cells and the phenotype of thymic lymphoma cells were analyzed using fluorescence-activated cell sorting (FACS). We found that most mice in the IR group developed thymic lymphoma, their survival rate decreasing to 20% after 180 days of IR exposure, whereas no mice died in the non-IR control group until day 400. The thymus and spleen weighed significantly more in the IR-4-month group than that in the non-IR group; however, we observed no significant differences between the body weights of the control and IR mice. FACS analysis indicated that the frequency of HR events significantly increased at two and four months after the last IR dose in the bone marrow and thymus cells, but not in the spleen cells of RaDR-GFP transgenic mice, suggesting that recombinant cells accumulated in the thymus upon IR exposure. This suggests that IR induces genome instability, revealed as increased HR, that drives the development of thymic lymphoma. Additionally, phenotypic analysis of lymphoma cells showed an increase in the CD4-/CD8+ (CD8SP) cell population and a decrease in the CD4+/CD8- (CD4SP) cell population in the IR-4-month group compared to that in the non-IR group, indicating that IR induces an aberrant cell phenotype characteristic of lymphoma. In conclusion, we observed a significant increase in HR events and abnormal phenotype in thymic lymphoma cells at two and four months after IR exposure in both the thymus and bone marrow tissues, suggesting that genomic instability is involved in the early stages of thymic lymphomagenesis. Our study indicates that HR-visualizing RaDR-GFP transgenic mice can help explore the links between the molecular mechanisms of genome instability and IR-induced tumorigenesis. 相似文献
944.
Junnosuke Hayasaka Daisuke Kikuchi Hiroyuki Odagiri Kosuke Nomura Yorinari Ochiai Takayuki Okamura Yugo Suzuki Yutaka Mitsunaga Nobuhiro Dan Masami Tanaka Satoshi Yamashita Akira Matsui Shu Hoteya 《Internal medicine (Tokyo, Japan)》2022,61(4):451
Objective Clipping is a common technique for managing colonic diverticular bleeding (CDB), despite the lack of published evidence regarding its effectiveness. We aimed to evaluate the effectiveness of clipping for CDB in preventing early recurrent bleeding. Methods This dual-center retrospective study included 93 patients who underwent emergency hospitalization for bloody stool, diagnosed with definitive CDB, and treated with clipping or conservative treatment. The primary outcome was early recurrent bleeding. A logistic regression analysis was performed to assess the association between the occurrence of early recurrent bleeding and clipping with adjustment for propensity scores. Secondary outcomes included death, transfusion, length of hospitalization, need for transcatheter arterial embolization or surgery, and adverse events. Results The patient characteristics were similar between the clipping (n=85) and conservative treatment (n=8) groups. The rate of early recurrent bleeding was significantly lower in the clipping group than in the conservative treatment group [23.5% (20 cases) vs. 75% (6 cases), p=0.005]. In the propensity score-adjusted logistic regression analysis, the odds ratio for early recurrent bleeding in the clipping group was 0.094 (95% confidence interval, 0.008-0.633, p=0.026). Secondary outcomes were not significantly different between the two groups. Stigmata of recent hemorrhage (SRH) at the time of recurrent bleeding was identified in 79.2% of patients (19/24). In the clipping group, recurrent bleeding was observed in 62.5% of cases (10/16) from the same diverticulum. However, early recurrent bleeding tended to be less likely with direct clipping (p=0.072). Conclusion Clipping for definite CDB was more effective in preventing early recurrent bleeding than conservative treatment. 相似文献
945.
946.
Akira Yokote Yuka Hayashi Shozaburo Yanamoto Shinsuke Fujioka Kazuo Higa Yoshio Tsuboi 《Internal medicine (Tokyo, Japan)》2022,61(5):633
Objective Leg muscle strength (LMS) is decreased in early-stage Parkinson disease (PD) patients and is associated with slower walking and falls. However, LMS in advanced PD has not been well investigated. The purpose of this study was to evaluate LMS in advanced PD patients and its effects on gait performance, activities of daily living, and the cognitive function. Methods The medical records of 132 patients with idiopathic advanced PD [Hoehn and Yahr (H&Y) stages 3 and 4] with a mean disease duration of 9.6 years were retrospectively reviewed. Leg extensor muscle strength of the patients was measured using a Strength Ergo 240. The associations between the LMS and gait performance, Barthel index, H&Y stage, and Mini-Mental State Examination (MMSE) score were analyzed. Results A Spearman''s correlation analysis showed that LMS was correlated with the sex, age, age of disease onset, H&Y stage, Barthel index, MMSE score, and gait parameters. A multivariable linear regression analysis for identifying predictors of LMS showed that the gait velocity (β=0.377), Barthel index (β=0.281), sex (β=-0.187), and disease duration (β=-0.155) were significant. A receiver operating characteristic curve analysis for discriminating between H&Y stage 3 and 4 was performed for LMS; the area under the curve was 0.774 (95% confidence interval=0.696-0.851). Conclusions LMS was strongly associated with multiple domains of clinical characteristics, especially gait velocity and the Barthel index. Our study also suggested that LMS can be a predictor of PD progression. 相似文献
947.
Akira Takamata Yuri Nishimura Ayano Oka Mayuna Nagata Natsumi Kosugi Sayaka Eguchi Hiroko Negishi Keiko Morimoto 《Nutrients》2022,14(6)
Sex steroids modify feeding behavior and body weight regulation, and androgen reportedly augments food intake and body weight gain. To elucidate the role of endogenous androgens in the feeding regulation induced by reduced glucose availability, we examined the effect of gonadectomy (orchiectomy) on food intake and orexin A neuron’s activity in the lateral hypothalamic/perifornical area (LH/PFA) in response to reduced glucose availability (glucoprivation) induced by 2-deoxy-d-glucose (2DG) administration in male rats. Rats (7W) were bilaterally orchiectomized (ORX group) or sham operated (Sham group). Seventeen days after the surgery, food intake response to 2DG (400 mg/kg, i.v.) was measured for 4 h after the infusion. The same experiment was performed for the immunohistochemical examination of c-Fos-expressing orexin A neurons in the LH/PFA and c-Fos expression in the arcuate nucleus (Arc). Food intake induced by glucoprivation was greater in the ORX group than the Sham group, and the glucoprivation-induced food intake was inversely correlated with plasma testosterone concentration. Glucoprivation stimulated c-Fos expression of the orexin A neurons at the LH/PFA and c-Fos expression in the dorsomedial Arc. The number and percentage of c-Fos-expressing orexin A neurons in the LH/PFA and c-Fos expression in the dorsomedial Arc were significantly higher in the ORX group than the Sham group. This indicates that endogenous androgen, possibly testosterone, diminishes the food intake induced by reduced glucose availability, possibly via the attenuated activity of orexin A neuron in the LH/PFA and neurons in the dorsomedial Arc. 相似文献
948.
Teizo Ueyama Noboru Mizuno Sakashi Nomura Akira Konishi Kazuo Itoh Hisao Arakawa 《The Journal of comparative neurology》1984,222(1):38-46
Central distribution of afferent and efferent components of the pudendal nerve was examined in the cat by the HRP method after applying HRP to the central cut end of the pudendal nerve. Retrogradely labeled neuronal cell bodies were located primarily in the feline homologue of the Onuf's X nucleus, constituting a slender longitudinal cell column in the ventral horn of the S1 and S2 cord segments. The Onuf's nucleus was present constantly from middle S1 to high S2 cord segments, and occasionally extended rostrally to high S1 or low L7, and caudally to middle S2, low S2, or high S3 cord segments. No sex differences were observed in the distribution pattern, number, and soma size of labeled neurons in the Onuf's nucleus. Transganglionically labeled dorsal root fibers were found to terminate ipsilaterally in the lamina I of the dorsal horn at levels of lower lumbar, sacral, and higher coccygeal cord segments and the gracile nucleus, and bilaterally with an ipsilateral predominance in the dorsal commissural gray and laminae III, IV, V, and VI of the dorsal horn at levels of lower lumbar, sacral, and higher coccygeal cord segments. Some labeled dorsal root fibers appeared to end ipsilaterally in the regions where the sacral parasympathetic preganglionic neurons have been shown to be located. 相似文献
949.
Yukiko Matsuda Tsuneyasu Terauchi Kota Murahira Seema Patil Vajendra Joshi Kazuyuki Araki Akira Taguchi Tomohiro Okano 《Oral Radiology》2014,30(1):20-26
Objectives
Digital subtraction radiography (DSR) is a suitable technique for detecting incipient bone changes. However, in DSR, one or more follow-up radiographs must be taken. The aim of this study was to assess the possibility of reducing the exposure time for the radiographs that follow the initial one.Methods
Maxillary premolar and molar radiographic images of a dry skull were taken with a digital radiography system. The initial radiographs, without bone chips, were taken at 0.32 and 0.16 s. Then, five bone chips (weight range 7–15 mg) were placed on the maxillary molar buccal side of the dry skull. Secondary radiographs were taken at 0.32-, 0.16-, 0.08-, 0.04-, and 0.02-s exposure times. For each bone chip, radiographs were taken three times. The secondary and initial images were subtracted to yield subtraction images. Four observers were asked to evaluate bone change visibility in the subtraction images. The Friedman test was used for statistical analysis.Results
Significant differences were seen at each of the settings for the 0.32-s group (p = 1.24e?030) and 0.16-s group (p = 7.52e?009). By comparing the different groups, observer evaluations indicated that visibility changed when the secondary radiograph was taken at 1/8 of the exposure time of the initial radiograph. In both groups, the visibility of the 0.02-s subtraction image was significantly lower than that of the other subtraction images.Conclusion
In DSR, the exposure time of the secondary radiograph can be reduced to 1/4 of the exposure time of the initial radiograph. 相似文献950.
Insulin‐Like Growth Factor I Inhibits Alveolar Bone Loss Following Tooth Extraction in Rats 下载免费PDF全文