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101.
102.
Su Jin Park Su Jin Kim Yumie Rhee Ji Hyun Byun Seong Hwan Kim Myoung Hee Kim Eun Jig Lee Sung-Kil Lim 《Journal of bone and mineral research》2007,22(6):889-896
The FIGNL1 gene was proven to be a new subfamily member of ATPases associated with diverse cellular activities (AAA proteins). In this in vitro study, the AAA proteins inhibited osteoblast proliferation and stimulated osteoblast differentiation. We showed that FIGNL1 may play some regulatory role in osteoblastogenesis. INTRODUCTION: The fidgetin-like 1 (FIGNL1) gene encodes a new subfamily member of ATPases associated with diverse cellular activities (AAA proteins). Although the FIGNL1 protein localizes to both the nucleus and cytoplasm, the function of FIGNL1 remains unknown. In a previous study, we identified several genes that mediate the anabolic effects of basic fibroblast growth factor (bFGF) on bone by using microarray data. FIGNL1 was one of the genes that downregulated >2-fold in MC3T3-E1 cells after treatment with bFGF. Therefore, this study was aimed to identify and confirm the function of FIGNL1 on osteoblastogenesis. MATERIALS AND METHODS: We examined the effect of the FIGNL1 gene on proliferation, differentiation, and apoptosis in mouse osteoblast cells (MC3T3-E1 and mouse primary calvarial cells) using flow cytometry, RT-PCR, cell proliferation assay, and cell death assay. MC3T3-E1 cells and mouse calvarial cells were transfected with small interfering RNA (siRNA) directed against the FIGNL1 or nontargeting control siRNA and examined by cell proliferation and cell death assays. Also, FIGNL1 was fused to enhance green fluorescent protein (EGFP), and the EGFP-fused protein was transiently expressed in MC3T3-E1 cells. RESULTS: Reduced expression of FIGNL1 by bFGF and TGF-beta1 treatment was verified by RT-PCR analysis. Overexpression of FIGNL1 reduced the proliferation of MC3T3-E1 and calvarial cells, more than the mock transfected control cells did. In contrast, siFIGNL1 transfection significantly increased the proliferation of osteoblasts, whereas overexpression of FIGNL1 did not seem to alter apoptosis in osteoblasts. Meanwhile, overexpression of FIGNL1 enhanced the mRNA expression of alkaline phosphatase (ALP) and osteocalcin (OCN) in osteoblasts. In contrast, siFIGNL1 decreased the expression of ALP and OCN. A pEGFP-FIGNL1 transfected into MCT3-E1 cells had an initially ubiquitous distribution and rapidly translocated to the nucleus 1 h after bFGF treatment. CONCLUSIONS: From these results, we proposed that FIGNL1, a subfamily member of the AAA family of proteins, might play some regulatory role in osteoblast proliferation and differentiation. Further analyses of FIGNL1 will be needed to better delineate the mechanisms contributing to the inhibition of proliferation and stimulation of osteoblast differentiation. 相似文献
103.
Fontan conversion with arrhythmia surgery. 总被引:2,自引:0,他引:2
Woong-Han Kim Hong Gook Lim Jeong Ryul Lee Joon Ryang Rho Eun Jung Bae Chung Il Noh Yong Soo Yoon Yong Jin Kim 《European journal of cardio-thoracic surgery》2005,27(2):250-257
OBJECTIVE: Hemodynamic abnormalities and refractory atrial arrhythmias in patients late after the Fontan operation result in significant morbidity and mortality. We reviewed our experience with Fontan conversion and concomitant arrhythmia surgery. METHODS: Between January 1996 and February 2004, 16 patients underwent Fontan conversion and arrhythmia surgery. Mean age at the initial Fontan operation was 5.1+/-3.5 (range: 2-15) years and mean age at Fontan conversion was 17.0+/-5.8 (range: 6-30). The initial Fontan operations were atriopulmonary connections in 14 patients, extracardiac lateral tunnel in 1, and intracardiac lateral tunnel in 1. The types of arrhythmia included atrial flutter in 10 patients and atrial fibrillation in 3. Fontan conversion operation was performed with intracardiac lateral tunnel in 5 patients and extracardiac conduit in 11. Arrhythmia surgery included isthmus cryoablation in 10 patients and right-sided maze in 3. RESULTS: There has been no mortality. At Fontan conversion operation, 7 patients required permanent pacemaker. All patients have improved to New York Heart Association class I or II. With a mean follow-up of 26.9+/-30.6 (range:1-87) months, 16 patients had sinus rhythm, 2 patients had transient atrial flutter which was well controlled, and 2 patients required permanent pacemaker during follow-up. CONCLUSIONS: Fontan conversion with concomitant arrhythmia surgery and permanent pacemaker placement is safe, improves New York Heart Association functional class, and has a low incidence of recurrent arrhythmias. In most patients, concomitant permanent pacemakers are needed. 相似文献
104.
Yusen Chen Jun Nakura Jing-Ji Jin Zhihong Wu Miyuki Yamamoto Michiko Abe Yasuharu Tabara Yoshikuni Yamamoto Michiya Igase Xiao Bo Katsuhiko Kohara Tetsuro Miki 《Hypertension research》2003,26(6):439-444
The beta-adrenoceptor (beta-AR)-stimulatory guanine nucleotide-binding (Gs) protein system has been shown to play important roles in the cardiovascular system. The gene encoding the alpha-subunit of Gs proteins (GNAS1) is a candidate genetic determinant for hypertension. Because alcohol consumption is known to affect blood pressure partly through the beta-AR-Gs protein system, we examined the possible interaction between GNAS1 T393C polymorphism and drinking status in the association with hypertension in the present study. As a result, a non-significant but reasonable trend supporting the presence of an interaction was shown (p = 0.076). In line with this trend, the T393C polymorphism significantly interacted with drinking status in the association with systolic blood pressure (p = 0.028). Moreover, supporting the presence of an interaction, T allele carriers consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than CC homozygotes in non-drinkers and light drinkers. In contrast, CC homozygotes consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than T allele carriers in moderate to heavy drinkers. The present study also showed a significant interaction between the T393C polymorphism and drinking status in the association with pulse pressure (p = 0.026), reflected by a significant association between the T393C polymorphism and pulse pressure in moderate to heavy drinkers (p = 0.026). These findings may be helpful in conducting further molecular and biological studies on the relationship among the effects of alcohol, the beta-AR-Gs protein system, and hypertension. 相似文献
105.
目的 评价血管紧张素Ⅱ、氨甲酰血红蛋白、醛固酮及甲状旁腺激素等在血液净化充分性中的意义。方法 120例慢性肾功能衰竭患者,按采用不同的透析膜分为3组:即聚砜膜、醋酸膜、铜仿膜。用放射免疫法测定其血管紧张素Ⅱ(AngⅡ)及醛固酮(ALD)浓度,化学发光法测甲状旁腺激素(PTH)。采用不同的血流量200ml/min及250ml/min比较。结果 对体内中、小分子物质清除率,聚砜膜〉醋酸膜〉铜仿膜。结论 高血流量、高通透性人工合成聚砜膜,对治疗慢性肾功能衰竭,提高肾功能不全患者的身心健康及生活质量、延长患者生命有很重要的临床意义。 相似文献
106.
107.
目的:观察葛根素对家兔肢体缺血再灌注所致心脏损伤的保护作用并探讨其机制.方法:家兔40只,随机分4组:Ⅰ组为假手术对照组、Ⅱ组为缺血再灌注组、Ⅲ组为葛根素低剂量治疗组、Ⅳ组为葛根素高剂量治疗组.免疫组化法检测心肌组织Bcl-2和Bax蛋白表达;原位缺口末端标记法(TUNEL)检测心肌细胞凋亡;比色法测定心肌组织超氧化物岐化酶(SOD)和髓过氧化物酶(MPO)活性,丙二醛(MDA)含量,测定血清乳酸脱氢酶(LDH)活性;通过生理记录仪观察心功能指标.结果:与Ⅱ组比较,Ⅲ、Ⅳ组左心室功能增强,且Ⅳ组的左心室收缩功能比Ⅲ组增强,同时,Ⅲ、Ⅳ组心肌组织MDA含量和血清LDH活性减少,Bax蛋白表达减少,Ⅳ组的心肌凋亡指数低于Ⅱ组,心肌Bcl-2表达高于Ⅱ组.结论:葛根素促进肢体缺血再灌注后心脏功能的恢复,表现为剂量依赖效应,其作用机制与抗氧化损伤和抗细胞凋亡有关. 相似文献
108.
Chang Hyun Lee Jung-Gi Im Jin Mo Goo Hyun Ju Lee Sung-Tae Hong Cheng Hua Shen Doo Hyun Chung Kyu Ri Son Jung Min Chang Hong Eo 《Korean journal of radiology》2007,8(5):372-381
OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus. 相似文献
109.
单纯下颌骨磨削法矫治下颌角肥大 总被引:7,自引:0,他引:7
目的 探讨下颌角肥大骨磨削法治疗的临床效果。方法 在局部肿胀麻醉下,采用口内切口入路,常规分离显露下颌骨,在预定需要矫正的下颌骨区域,使用特殊器械磨削下颌骨体外侧皮质骨、下颌骨下缘及下颌角骨质,同时对部分肥大的咬肌进行处理,矫治下颌角肥大。结果 对58例下颌角肥大患者均行下颌骨磨削法矫治,除1例术中损伤下齿槽血管引起出血外,无其他并发症发生。术后随访6~18个月,全部病例取得良好的矫治效果。结论 下颌骨磨削法矫治下颌角肥大是一种并发症少、安全有效的好方法。与截骨矫治下颌角肥大的方法相比,该术式保留了下颌骨的内板。维持了颌颈区的立体感。 相似文献
110.
胸腰椎骨折术后内固定松动、断裂的原因及预防 总被引:14,自引:3,他引:11
目的 探讨椎弓根螺钉系统用于胸腰椎骨折术后出现松动、断裂的原因,并提出相应的预防对策。方法 12例胸腰椎骨折术后内固定失效病例,采用RF系统3例,AF系统9例。均未行植骨融合,AF系统中未按要求安装横连结3例,术后伤椎前缘高度平均恢复至正常的85.2%。结果 术后8—21个月出现棒断裂4例,螺钉断裂3例,钉帽松动5例。结论 内固定物的自身问题、术者的经验欠缺及操作不规范是胸腰椎骨折术后椎弓根螺钉系统松动、断裂的原因,但伤椎骨结构未能得到良好重建及术后椎间盘退变可能是其更重要的因素。因此重视内固定物的选择、加强规范操作,强调对损伤椎体及椎间盘的全面处理是预防内固定失效的有效措施。 相似文献