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101.
Regeneration of defects in articular cartilage in rat knee joints by CCN2 (connective tissue growth factor). 总被引:7,自引:0,他引:7
Takashi Nishida Satoshi Kubota Shunji Kojima Takuo Kuboki Kyouji Nakao Toshihiro Kushibiki Yasuhiko Tabata Masaharu Takigawa 《Journal of bone and mineral research》2004,19(8):1308-1319
CTGF/CCN2, a hypertrophic chondrocyte-specific gene product, possessed the ability to repair damaged articular cartilage in two animal models, which were experimental osteoarthritis and full-thickness defects of articular cartilage. These findings suggest that CTGF/CCN2 may be useful in regeneration of articular cartilage. INTRODUCTION: Connective tissue growth factor (CTGF)/CCN2 is a unique growth factor that stimulates the proliferation and differentiation, but not hypertrophy, of articular chondrocytes in vitro. The objective of this study was to investigate the therapeutic use of CTGF/CCN2. MATERIALS AND METHODS: The effects of recombinant CTGF/CCN2 (rCTGF/CCN2) on repair of damaged cartilage were evaluated by using both the monoiodoacetic acid (MIA)-induced experimental rat osteoarthritis (OA) model and full-thickness defects of rat articular cartilage in vivo. RESULTS: In the MIA-induced OA model, quantitative real-time RT-PCR assays showed a significant increase in the level of CTGF/CCN2 mRNA, and immunohistochemical analysis and in situ hybridization revealed that the clustered chondrocytes, in which clustering indicates an attempt to repair the damaged cartilage, produced CTGF/CCN2. Therefore, CTGF/CCN2 was suspected to play critical roles in cartilage repair. In fact, a single injection of rCTGF/CCN2 incorporated in gelatin hydrogel (rCTGF/CCN2-hydrogel) into the joint cavity of MIA-induced OA model rats repaired their articular cartilage to the extent that it became histologically similar to normal articular cartilage. Next, to examine the effect of rCTGF/CCN2 on the repair of articular cartilage, we created defects (2 mm in diameter) on the surface of articular cartilage in situ and implanted rCTGF/CCN2-hydrogel or PBS-hydrogel therein with collagen sponge. In the group implanted with rCTGF/CCN2-hydrogel collagen, new cartilage filled the defect 4 weeks postoperatively. In contrast, only soft tissue repair occurred when the PBS-hydrogel collagen was implanted. Consistent with these in vivo effects, rCTGF/CCN2 enhanced type II collagen and aggrecan mRNA expression in mouse bone marrow-derived stromal cells and induced chondrogenesis in vitro. CONCLUSION: These findings suggest the utility of CTGF/CCN2 in the regeneration of articular cartilage. 相似文献
102.
Alberto Falchetti Marco Di Stefano Francesca Marini Francesca Del Monte Carmelo Mavilia Debora Strigoli Maria L De Feo Giovan Isaia Laura Masi Antonietta Amedei Federica Cioppi Valentina Ghinoi Susanna Maddali Bongi Giuseppina Di Fede Carmela Sferrazza Giovan B Rini Daniela Melchiorre Marco Matucci-Cerinic Maria L Brandi 《Journal of bone and mineral research》2004,19(6):1013-1017
PDB is genetically heterogeneous. Mutations of the sequestosome1 gene have been reported in sporadic and familial forms of Paget's in patients of French Canadian and British descent. Mutational analyses in different ethnic groups are needed to accurately investigate hereditary diseases. We describe two novel mutations of sequestosome1 in 62 Italian sporadic patients, confirming the role of the encoded protein in this disorder. INTRODUCTION: Paget's disease of bone (PDB) is a relatively common disease of bone metabolism reported to affect up to 3% of whites over 55 years of age. The disorder is genetically heterogeneous, and at present, there is scientific evidence that at least eight different human chromosomal loci are correlated with its pathogenesis. Mutations of the sequestosome1 (SQSTM1) gene were identified as responsible for most of the sporadic and familial forms of Paget in patients of French Canadian and British descent. Such mutations were located at exon 7 and 8 levels, encoding for the ubiquitin protein-binding domain (UBA) and representing a mutational hot spot area. MATERIALS AND METHODS: To verify the involvement of this gene in Italian subjects affected by PDB, we performed mutational analysis in 62 sporadic PDB cases. RESULTS: We described three different mutations at exon 8 level: P392L, already described in the French Canadian population and families predominantly of British descendent, and two novel mutations consisting of the amino acid substitutions M404V and G425R. No significant differences in the clinical history of PDB have been observed in patients with SQSTM1 mutations in respect to those without. CONCLUSIONS: Even though our findings suggest a minor involvement of the SQSTM1 gene in the pathogenesis of sporadic Italian Paget's cases, the identification of different significant mutations within the SQSTM1 gene in unrelated, but clinically similar individuals, offers extremely convincing evidence for a causal relationship between this gene and PDB. Longitudinal studies are needed to assess the penetrance of genotype/phenotype correlations. Our findings confirm the evidence of a clustered mutation area at this level in this disorder. 相似文献
103.
Claudio R Cernea Alberto R Ferraz Inês V de Castro Miriam N Sotto Angela F Logullo Carlos E Bacchi André S Potenza 《Otolaryngology--head and neck surgery》2006,134(3):471-475
BACKGROUND: Some skin carcinomas may be very aggressive. Increased expression of the protein p53 has been associated with tumor aggressiveness. In this study, p53 expression was evaluated in basal cell carcinomas (BCC) and squamous cell carcinomas (SCC) with skull base invasion, and was compared to tumors with good outcome. STUDY DESIGN AND SETTING: Expression of p53 was immunohistochemically analyzed and it was reported as present or absent in 24 BCC and 11 SCC with skull base invasion. Control group (good outcome) included 23 BCC and 10 SCC. RESULTS: Expression of p53 was noted in 70.83% of BCC with skull base invasion, compared to 43.48% in the control group (P = 0.058). Regarding SCC, p53 positivity was noted in only 9.09% of SCC with skull base invasion, compared to 40.00% in the control group (P = 0.149). CONCLUSIONS: In this study, p53 expression was more common among BCC with skull base invasion, compared to controls with good outcome, and the difference was considered marginally significant. This proportion was reversed in SCC, but the difference was not statistically significant. EBM rating: B-3b. 相似文献
104.
Samuel E. Lynch DMD DMSc ; Stephen B. Trippel MD ; Richard D. Finkelman DDS PhD ; Rafael A. Hernandez DMD ; Christopher P. Kiritsy BA ; Harry N. Antoniades PhD 《Wound repair and regeneration》1994,2(3):182-190
The combination of insulin-like growth factor-I and platelet-derived growth factor-BB has previously been shown to stimulate healing of soft tissue wounds and the formation of bone and ligament around teeth. The purpose of the present study was to evaluate the effects of platelet-derived growth factor-BB and insulin-like growth factor-I individually and in combination on the healing of osseous wounds. Four standardized cortical wounds were created in each tibia of 11 adult Yucatan miniature pigs. The wounds in one tibia per animal were treated with either purified recombinant human insulin-like growth factor-I, platelet-derived growth factor-BB, or both in a methylcellulose gel. The wounds in each contralateral tibia received placebo gel alone. Coded serial sections of each wound were evaluated by computer-aided histomorphometry 21 days after surgery. The area and perimeter of the newly formed mineralized callus, the thickness of the total callus, and the percentage of mineralized tissue within the callus were significantly increased compared with the values of matched controls only in wounds treated with a combination of insulin-like growth factor-I and platelet-derived growth factor-BB. No significant differences in the measured parameters of callus formation were found in wounds treated with either insulin-like growth factor-I or platelet-derived growth factor-BB alone. Cartilage was present only in sites treated with insulin-like growth factor-I alone. These results suggest that the combination of platelet-derived growth factor-BB and insulin-like growth factor-I stimulates bone formation in wounds in long bones of adult animals and that these growth factors act via different pathways during the repair process. 相似文献
105.
Enrico Verrina Barbara Andreetta Sergio Bassi Roberto Bonaudo Domenica A. Caringella Alfonso Castellani Pierluigi Cavalli Alberto Edefonti Giancarlo Lavoratti Luigi Longo Ivana Pela Rosa Penza Francesco Perfumo Virgilio Petrucci Marina Picca Mauro Ragaiolo Stefano Rinaldi Gianfranco Rizzoni Palma Sorino Giusto Viglino Graziella Zacchello Rosanna Gusmano 《Pediatric nephrology (Berlin, Germany)》1992,6(1):78-81
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%. 相似文献
106.
107.
Developmental changes in beta-adrenoceptors, muscarinic cholinoceptors and Ca2+ channels in rat ventricular muscles. 总被引:2,自引:2,他引:0 下载免费PDF全文
M. Kojima T. Ishima N. Taniguchi K. Kimura H. Sada N. Sperelakis 《British journal of pharmacology》1990,99(2):334-339
1. In an attempt to explain the previous electrophysiological data on the ontogeny of beta-adrenergic and muscarinic cholinergic interactions on cardiac Ca2+ current, biochemical studies were performed on the ontogeny of beta-adrenoceptors, muscarinic cholinoceptors and Ca2+ channels in cardiac muscle of developing rats: 16-20 days old foetuses, 0-20 days old neonates, and 2-3 months old adults. 2. Developmental changes in cardiac beta-adrenoceptors, muscarinic cholinoceptors, and Ca2+ channels were determined with the use of specific radioligands, [3H]-dihydroalprenolol (DNA), [3H]-quinuclidinyl benzilate (QNB), and [3H]-nitrendipine (NTD), respectively. 3. The Bmax value (fmol mg-1 tissue) for [3H]-DNA binding started to increase on post-gestation day 20, reached almost its maximum level on neonatal day 6, kept almost the same level until neonatal day 20, and then decreased slightly to its adult level. 4. The Bmax value (fmol mg-1 tissue) for [3H]-QNB binding started to increase on post-gestation day 16, reached almost its maximum level on neonatal day 0, remained almost constant until neonatal day 15, and then decreased to its adult level. 5. The Bmax value (fmol mg-1 tissue) for [3H]-NTD binding increased with age between post-gestation day 18 and neonatal day 15, stayed almost constant until neonatal day 20, and then decreased to its adult level. 6. The Kd values for [3H]-DHA, [3H]-QNB, and [3H]-NTD bindings remained almost constant during the developmental period examined.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
108.
When complex prostheses are fabricated, it is expected that at some point maintenance will be necessary. This clinical report documents a 10-year-old maxillary spark erosion prosthesis that had been repaired many times, was discolored, and exhibited significant signs of wear. The metal superstructure was intact; therefore, only the acrylic resin base and teeth needed to be replaced. To reduce both cost and time without the prosthesis for the patient, the rehabilitation was completed within 24 hours. 相似文献
109.
Tissue specimens from patients with the scirrhous type of gastric carcinoma were stained using the peroxidase-antiperoxidase (PAP) method. Nine out of thirty-seven specimens (24 per cent) showed positive estrogen staining, and here tissues from male or older patients were usually stained. Cumulative survival rate in patients whose tissue showed a positive estrogen staining was higher than that in case of a negative estrogen staining. Four out of thirty-one specimens (13 per cent) stained positively for progesterone, all four patients being male. These results suggest that estrogen and progesterone may relate to the growth of the scirrhous type of gastric cancer. 相似文献
110.
T Kokubo Y Ohtomo J Iseki T Toyoda S Kondo F Hattori K Itoh K Kojima 《Radiation Medicine》1986,4(4):124-126
The case of a 38-year-old man with an exogastric leiomyoblastoma is reported. CT and ultrasound examinations revealed a large mass in the left hypochondrium that had both solid and cystic components. These findings mimicked those of cystadenoma of the pancreas. Because of intraperitoneal hemorrhage in the preoperative course, emergency laparotomy was performed. A large tumor was found to arise from the greater curvature of the stomach. The diagnosis was confirmed histologically. 相似文献