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991.
Inoue M Nakamura T Shigeno K Ueda H Tamura N Fukuda S Liu Y Nakahara T Toba T Yoshitani M Iizuka T Shimizu Y 《The International journal of artificial organs》2000,23(12):845-851
The authors have developed a new artificial dental implant and evaluated it in a dog model in terms of its potential to produce: I) regeneration of junctional epithelium; II) regeneration and attachment of connective tissue. The implants were constructed from allo-teeth. We removed the cell components from the periodontal ligaments of these teeth with a detergent (1% TritonX-100); the remaining acellular periodontal ligament acted as an extracellular matrix upon which regeneration and attachment could proceed. We placed 10 of these implants in the just-extracted sites of three beagle dogs. We observed regeneration of both junctional epithelium and connective tissue at all implant sites after 3 months. The connective tissue was attached in all cases. Use of the acellular periodontal ligament as an extracellular matrix may facilitate regeneration of host periodontal ligament tissue, thus contributing to recovery of host immunological defense and long-term oral function. 相似文献
992.
Miyasaka K Ichikawa M Kawanami T Kanai S Ohta M Sato N Ebisawa H Funakoshi A 《Mechanisms of ageing and development》2003,124(2):183-190
Laboratory rats are normally confined to cages that markedly restrict their physical activity. In these rats, the resting energy expenditure accounts for 90% of the total daily energy expenditure, while the daily physical activity in humans consumes 30% of the total daily energy expenditure. Otsuka Long Evans Tokushima Fatty (OLETF) rats have been developed as a model of non-insulin-dependent diabetes mellitus (NIDDM) with mild obesity, and obesity is an important factor that induces diabetes in this strain. We implemented a running-wheel exercise regimen that was the equivalent of normal physical activity to provide light exercise for OLETF rats. The purpose of the study was to determine if light exercise improves the age-related decline in energy metabolism and glucose intolerance in OLETF rats. The effects were also compared in control Long Evans Tokushima (LETO) rats. From 12 to 46 weeks of age, the rats performed a running-wheel exercise (3000 m/day). Energy metabolism was determined at 8-week intervals. The typical increase in body weight was significantly decreased in OLETF rats in response to exercise, while no significant effect was observed in LETO rats. Energy expenditure and basal metabolic rate (BMR) per kilogram body weight (not whole-body weight) were increased by exercise in OLETF rats, but not in LETO rats. At 46 weeks of age, after exercise, the blood glucose and hemoglobin (Hb)A1c levels, as well as the plasma levels of insulin, triglyceride, cholesterol, and leptin significantly decreased in OLETF rats, while only the plasma levels of cholesterol and leptin significantly decreased in LETO rats. Light exercise thus appears to be beneficial for preventing age-related decline in energy metabolism and glucose intolerance in OLETF rats. 相似文献
993.
Tomoya Suzuki Keisuke Nojiri Satoshi Higurashi Yuta Tsujimori Yasuhiro Toba Kyoko Nomura 《Nutrients》2022,14(6)
This study investigated whether parenting stress is associated with breastfeeding type (exclusive or partial). Between 2014 and 2019, we recruited 1210 healthy mothers (mean age, 31.2 years; 65%, multiparity) from 73 obstetric institutions across all prefectures of Japan. Among these, 1120 mothers at two months and 1035 mothers at six months were investigated for parenting stress and breastfeeding type: exclusive versus otherwise (partial). Parenting stress was measured by a validated Japanese scale consisting of childcare exhaustion, worry about child’s development, and no partner support. Exclusive breastfeeding prevalence was 75% at two and 78% at six months. The total scores for childcare exhaustion and worry about child development were statistically higher in the partial breastfeeding group than in the exclusive breastfeeding group at two months but not at six months. A logistic regression model demonstrated that childcare exhaustion was significantly associated with an increased risk of having partial breastfeeding at two months after adjusting for the maternal Body Mass Index, parity, and baby’s current weight. However, the association was no longer significant at six months. The present study suggests that intervention for parenting stress at two months postpartum may promote prolonged exclusive breastfeeding. 相似文献
994.
995.
Takako Yokozawa Erbo Dong Teruto Yasui Atsushi Muraguchi 《Phytotherapy research : PTR》1998,12(2):135-137
In terms of the rate of DNA fragmentation and electrophoresis patterns, we demonstrated that apoptosis was induced in LLC-PK1 cells subjected to the Fenton reaction with H2O2 and Fe2+. In addition, Wen-Pi-Tang, which is known to inhibit the progression of renal failure in both an experimental and a clinical setting, was found to suppress this apoptosis. © 1998 John Wiley & Sons, Ltd. 相似文献
996.
Takako Yokozawa Atsutoshi Tsuji Masao Hattori Hikokichi Oura Toshiyuki Kaji Yasuyuki Fujiwara Kunihiko Wakaki Fumitomo Koizumi Mineo Shimizu 《Phytotherapy research : PTR》1996,10(3):224-227
A significant increase in high-density lipoprotein-cholesterol and a tendency for total cholesterol and low-density lipoprotein-cholesterol to decrease were found in parous rats given Hokoei-to orally for 25 days, resulting in improvement of the atherogenic index. In experiments using cells of vascular origin, significantly increased proliferation of endothelial cells and suppressed proliferation of smooth muscle cells were obtained in the presence of Hokoei-to. When the action of each component galenical of Hokoei-to was examined, all five components, i.e. Taraxaci Radix, Angelicae Radix, Cyperi Rhizoma, Moutan Cortex and Dioscoreae Rhizoma, promoted the proliferation of endothelial cells. However, Taraxaci Radix and Angelicae Radix also promoted the growth of smooth muscle cells, showing inconsistency with the effect of Hokoei-to as a whole. 相似文献
997.
Shuji Ogino Mohan Brahmandam Mami Cantor Chungdak Namgyal Takako Kawasaki Gregory Kirkner Jeffrey A Meyerhardt Massimo Loda Charles S Fuchs 《Modern pathology》2006,19(1):59-68
Signet ring cell carcinoma and mucinous carcinoma are distinct subtypes of colorectal adenocarcinoma. The morphologic and molecular spectra of colorectal carcinomas with various signet ring cell components and colorectal carcinomas with various mucinous components, compared to non-mucinous adenocarcinomas, have not been examined. The study groups consisted of 39 carcinomas with various signet ring cell components ('the signet group'), 167 carcinomas with various mucinous components ('the mucinous group'), and 457 nonmucinous adenocarcinoma. We visually estimated the amounts of signet ring cell and mucinous components in tumors, and subclassified the signet and mucinous groups according to the amount of each component (< or = 19, 20-49, and > or = 50%). We sequenced BRAF and KRAS, analyzed for microsatellite instability (MSI) and 18q loss of heterozygosity (LOH), and performed immunohistochemistry for TP53, cyclooxygenase-2 (COX2), MLH1, O-6-methylguanine DNA methyltransferase (MGMT), p16 (CDKN2A), and fatty acid synthase (FASN). Signet ring cell carcinoma (> or = 50% signet ring cell tumors) and < or = 49% signet ring cell tumors showed similar molecular features. Except for MSI and MGMT, > or = 50% mucinous tumors and < or = 49% mucinous tumors also showed similar molecular features. BRAF mutations, MSI, and MLH1 loss were more frequent in both the signet and mucinous groups than nonmucinous carcinoma. More frequent KRAS mutations and less frequent p16 loss and TP53 positivity were observed in the mucinous group than nonmucinous carcinoma. 18q LOH and COX2 overexpression were less common in the signet group than nonmucinous carcinoma. FASN levels were highest in the mucinous group, followed by nonmucinous carcinoma, and lowest in the signet group. In conclusion, a minor (< or = 49%) signet ring cell or mucinous component in colorectal carcinoma suggests molecular features similar to > or = 50% signet ring cell or mucinous carcinoma, respectively. Signet ring cell carcinoma and mucinous carcinoma are related subtypes of colorectal adenocarcinoma, but have molecular features distinct from each other. 相似文献
998.
999.
Yuriko Saito Takako Furukawa Yasushi Arano Yasuhisa Fujibayashi Tsuneo Saga 《Nuclear medicine and biology》2008,35(8):851-860
IntroductionVarious techniques are available for in vivo imaging, and precise understanding of their characteristics is essential for effective use of the imaging results. We established human mesothelioma cell lines expressing red fluorescent protein (RFP) and examined their fluorescence intensity and uptake of positron emission tomography (PET) tracer analogs to compare their characteristics and assess their usefulness in the evaluation of therapeutics.MethodA human mesothelioma cell line was stably transfected to express RFP. Fluorescence, cell number and protein amount were measured during cell growth and treatment with cytotoxic reagents. In in vivo experiments, RFP-expressing cells were injected subcutaneously or into the pleural cavity of nude mice, and fluorescence images were taken with or without pemetrexed treatment. The uptake of [3H]3′-deoxy-3′-fluorothymidine ([3H]FLT) and [14C]2-fluoro-2-deoxy-d-glucose ([14C]FDG) under treatment with the above reagents in vitro and in vivo were examined.ResultsStrong correlation was observed between fluorescence intensity and total cell number with or without cytotoxic treatment. The uptake of [3H]FLT and [14C]FDG decreased rapidly after the initiation of treatment with actinomycin D or cycloheximide. When treated with pemetrexed, the uptake of [3H]FLT temporarily increased. The cells formed subcutaneous and orthotopic tumors, with fluorescence intensity correlating with tumor volume. The correlation was sustained under pemetrexed treatment. The uptake of [3H]FLT in vivo increased significantly early after pemetrexed treatment.ConclusionFluorescence imaging could be used to semiquantitatively monitor tumor size, whereas PET could be used to monitor tumor response to therapeutic treatments, and especially, FLT might be a good marker of the response to anti-folate chemotherapeutics. 相似文献
1000.
Takeshi Onda Satoshi Mashiko Megumi Hamano Isao Tomita Takako Tomita 《Clinical and experimental pharmacology & physiology》1994,21(11):857-863
1. Endothelium-dependent relaxation (EDR) in aortic rings from young (8 weeks) and adult (16 weeks and 20 weeks) stroke-prone spontaneously hypertensive rats (SHRSP) was investigated in comparison with age-matched Wistar-Kyoto rats (WKY). 2. At 8 weeks, acetylcholine (3×10?-9-?10?-5 mol/L) and ionomycin (4×10?8-10?6 mol/L)-induced EDR in SHRSP aortae was significantly enhanced compared to that in WKY aortae. Mechanical denudation of the endothelium completely abolished, and pretreatment of aortae with NG-monomethyl L-arginine (1 mmol/L), an inhibitor of nitric oxide formation, greatly reduced the relaxation in both strains. Indomethacin (10?5 mol/L), a cyclo-oxygenase inhibitor that blocks the production of endothelium-derived contracting factors, did not significantly alter the relaxation by acetylcholine at this age. There was no difference in endothelium-independent relaxation of denuded aortae by sodium nitroprusside (10?9-10?6 mol/L) and 8-bromoguanosine 3‘, 5‘-cyclic monophos-phate (10?6-10?3 mol/L). 3. In adult SHRSP with established hypertension, however, the acetylcholine (10?8-?10?5 mol/L)-induced relaxation markedly diminished at any of the concentrations tested compared to that observed in 8 week old SHRSP and WKY at 8–20 weeks of age. This finding differed from other observations where the relaxation in SHRSP was impaired only at higher concentrations of acetylcholine. Indomethacin pretreatment of aortae from 20 week old SHRSP restored acetylcholine-induced EDR to a level comparable with that in age-matched WKY. 4. These results suggest that the aorta from young SHRSP releases more endothelium-derived relaxing factors in response to acetylcholine and ionomycin, but the relaxation greatly diminishes in adult SHRSP with established hypertension. This may be due to counteraction of endothelium-derived contracting factors released from the endothelium with functional changes resulting from the long duration of the hypertension. 相似文献