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21.
22.
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
23.
24.
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
25.
26.
The ultrasonograms of ulcerative colitis (UC) in active stage show hypoechoic changes of the colorectal wall from the mucosal layer to the deeper layers. These endoscopic ultrasound (EUS) changes of the wall recognized in active stage disappear or normalize in the stage of remission. When the stage of UC is exacerbated, the hypoechoic changes of the wall extend from the mucosal layer to the deeper layers with the increase of wall thickness. These EUS images of active UC are classified into the following types: UC‐M, thickening of the whole wall with the structure preserved; UC‐SM, hypoechoic changes reach the superficial portion of third layer with the thickening of whole wall; UC‐SM deep, hypoechoic changes reach the deeper portion of third layer with the thickening of whole wall; UC‐MP, hypoechoic changes reach the fourth layer with the thickening of whole wall; UC‐SS/SE, hypoechoic changes penetrate through the fourth layer with the thickening of whole wall. With the help of EUS we can demonstrate the severity of inflammation in UC. Moreover, in severe cases of UC, the treatment strategy including emergency surgery can be determined. EUS is a valuable method in the management of UC. 相似文献
27.
28.
W. S. Hong Y. I. Min H. T. Kim Y. B. Cho K. H. Kim D. K. Kim 《Journal of Korean medical science》1995,10(4):269-274
In an attempt to develop a new anticancer platinum complex with greater or equivalent antitumor activity but reduced side effects compared with cisplatin (CDDP), a series of new platinum complexes having a glycolate leaving ligand was synthesized. Among them, five complexes were selected for further development on the basis of adequate water solubility, low nephrotoxicity and high antitumor activity in a murine system. The chemosensitivity of these five complexes was examined in MTT assay against two human pulmonary adenocarcinoma cell lines, PC-9 and PC-14, and two human stomach adenocarcinoma cell lines, MKN-45 and KATO III. Their IC50 and relative antitumor activity (RAA) values were compared with those of CDDP and 254-S, a second-generation platinum complex with a glycolate leaving ligand under phase III clinical trial. The lowest mean IC50 value was observed in CDDP, followed by SKI 2034R and SKI 2033R. In this study, the antitumor activity was evaluated in terms of RAA values and SKI 2034R showed the highest RAA value. The order of RAA values was SKI 2034R > CDDP > SKI 2032R > SKI 2033R > SKI 2030R > SKI 2029R > 254-S. Based on the RAA order, we have recommended SKI 2034R as the most promising candidate for further development of a clinically useful platinum complex. 相似文献
29.
We present three unusual cases of molluscum contagiosum occurring in epidermal cysts. All of them are asymptomatic, elevated, oval nodules diagnosed clinically as epidermal inclusion cyst or prurigo nodularis. Histology showed true epidermal cysts containing molluscum bodies throughout the cyst wall and some type of laminated material within the cyst itself. The lesion, in all three cases developed in the pubic area of young adult men. 相似文献
30.
Mitogenic, chemotactic, and synthetic responses of rat periodontal ligament fibroblastic cells to polypeptide growth factors in vitro. 总被引:9,自引:0,他引:9
The mitogenic, chemotactic, and synthetic responses of rat periodontal ligament (PDL) fibroblastic cells to epidermal growth factor (EGF), transforming growth factor-beta (TGF-beta), recombinant human platelet-derived growth factor (rhPDGF)-AB, rhPDGF-BB, natural (n) PDGF-AB, and insulin-like growth factor-I (IGF-I) were examined in vitro using PDL cells obtained from the coagulum of healing tooth sockets. PDGFs and IGF-I have potent and comparable mitogenic effects on PDL fibroblastic cells. The maximum mitogenic effect of PDGFs was observed at the concentration of 10 ng/ml, whereas that of IGF-I was seen at concentrations higher than 100 ng/ml. In contrast, EGF induced moderate, and TGF-beta inhibitory mitogenic responses. The combination of rhPDGF-AB with either EGF or TGF-beta demonstrated comparable mitogenic potency, equivalent to the level of PDGF alone regardless of the mitogenic effect of other growth factors. The combination of rhPDGF-AB and IGF-I, however, showed a synergistic effect revealing the highest mitogenic effect among all individual growth factors as well as any combinations of the growth factors tested. Similarly, PDL fibroblastic cells demonstrated strong chemotactic responses to both IGF-I and PDGFs. The maximum effect was observed by IGF-I at concentrations higher than 10 ng/ml, followed by rhPDGF-BB at 0.1 ng/ml, rhPDGF-AB and nPDGF at concentrations ranging from 0.1 to 1 ng/ml. TGF-beta revealed no, and EGF slightly increased, chemotactic effects. IGF-I slightly enhanced the synthesis of total protein, whereas other factors had no significant effect. However, both rhPDGF-AB and TGF-beta stimulated collagen synthesis. On the other hand, IGF-I showed no effect on collagen synthesis, while EGF suppressed collagen synthesis. These findings suggest that rhPDGF-BB and IGF-I stimulate proliferation and chemotaxis of PDL fibroblastic cells. In addition, the combination of these growth factors further increases the mitogenic effect. rhPDGF-AB also stimulates collagen synthesis by PDL fibroblastic cells. Thus, rhPDGF-BB and IGF-I may have important roles in promotion of PDL healing, and consequently, may be useful for clinical application in periodontal regenerative procedures. 相似文献