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1.
Osteoarthritis Cartilage ; 30(3): 451-460, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34906679

RESUMO

OBJECTIVE: It has been debated whether the onset of knee osteoarthritis is initiated in cartilage or subchondral bone. The purpose of this study was to clarify the effects of increasing or decreasing joint instability on cartilage degeneration and subchondral bone changes in knee OA by comparing different models of joint instability. DESIGN: We used the anterior cruciate ligament transection (ACL-T) model and the destabilization of the medial meniscus (DMM) model. In addition, we created a controlled abnormal tibial translation (CATT) model and a controlled abnormal tibial rotation (CATR) model. We performed joint instability analysis, micro-computed tomography analysis, histological and immunohistological analysis in 4 and 6 weeks. RESULTS: The CATT group suppressed joint instability in the ACL-T group (6 weeks; P = 0.032), and the CATR group suppressed joint instability in the DMM group (6 weeks; P = 0.032). Chondrocyte hypertrophy in the ACL-T and DMM groups was increased compared to the Sham group (6 weeks; [ACL-T vs Sham], P = 0.002, 95%CI [5.983-33.025]; [DMM vs Sham], P = 0.022, 95%CI [1.691-28.733]). In the subchondral bone, the BV/TV in the DMM and CATR groups was increased compared to the ACL-T and CATT groups (6 weeks; [DMM vs ACL-T], P = 0.002, 95%CI [7.404-37.582]; [DMM vs CATT], P = 0.014, 95%CI [2.881-33.059]; [CATR vs ACL-T], P = 0.006, 95%CI [4.615-34.793]; [CATR vs CATT], P = 0.048, 95%CI [0.092-30.270]). CONCLUSIONS: This study showed that joint instability promotes chondrocyte hypertrophy, but subchondral bone changes were influenced by differences in ACL and meniscus function.


Assuntos
Lesões do Ligamento Cruzado Anterior/complicações , Doenças das Cartilagens/etiologia , Instabilidade Articular/complicações , Osteoartrite do Joelho/etiologia , Lesões do Menisco Tibial/complicações , Animais , Condrócitos/patologia , Modelos Animais de Doenças , Masculino , Camundongos
2.
Oncogene ; 32(17): 2140-9, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-22689052

RESUMO

Tumor-suppressor genes on chromosome X can be inactivated by a single hit, any of the point mutations, chromosomal loss and aberrant DNA methylation. As aberrant DNA methylation can be induced frequently, we here aimed to identify a tumor-suppressor gene on chromosome X inactivated by promoter DNA methylation. Of 69 genes on chromosome X upregulated by treatment of a gastric cancer cell line with a DNA-demethylating agent, 5-aza-2'-deoxycytidine, 11 genes had low or no expression in the cell line and abundant expression in normal gastric mucosae. Among them, FHL1 was frequently methylation-silenced in gastric and colon cancer cell lines, and methylated in primary gastric (21/80) and colon (5/50) cancers. Knockdown of the endogenous FHL1 in two cell lines by two kinds of shRNAs significantly increased cell growth in vitro and sizes of xenografts in nude mice. Expression of exogenous FHL1 in a non-expressing cell line significantly reduced its migration, invasion and growth. Notably, a somatic mutation (G642T; Lys214Asn) was identified in one of 144 colon cancer specimens, and the mutant FHL1 was shown to lack its inhibitory effects on migration, invasion and growth. FHL1 methylation was associated with Helicobacter pylori infection and accumulated in normal-appearing gastric mucosae of gastric cancer patients. These data showed that FHL1 is a methylation-silenced tumor-suppressor gene on chromosome X in gastrointestinal cancers, and that its silencing contributes to the formation of an epigenetic field for cancerization.


Assuntos
Neoplasias do Colo/genética , Inativação Gênica , Genes Supressores de Tumor , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Proteínas Musculares/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Sequência de Bases , Neoplasias do Colo/metabolismo , Ilhas de CpG , Metilação de DNA , Análise Mutacional de DNA , Epigênese Genética , Feminino , Mucosa Gástrica/metabolismo , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Transplante de Neoplasias , Regiões Promotoras Genéticas , Neoplasias Gástricas/metabolismo , Cromossomo X
3.
Kyobu Geka ; 64(5): 370-4, 2011 May.
Artigo em Japonês | MEDLINE | ID: mdl-21591436

RESUMO

Left ventricular pseudoaneurysm is a rare complication of myocardial infarction. However, the risk of rupture and heart failure are high, especially in a case of rapidly expanding aneurysm. As for left ventricular pseudoaneurysm, the risk of operation is high, and the long-term results are not good. We experienced 2 cases The 1st case was lost due to methicillin-resistant Staphylococcus aureus (MRSA) pneumonia The 2nd case is alive and has been free from heart failure for 3 years. The early diagnosis and surgery is necessary for a pseudoaneurysm.


Assuntos
Falso Aneurisma/cirurgia , Aneurisma Cardíaco/cirurgia , Idoso , Feminino , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações
4.
Eur J Clin Nutr ; 64(7): 714-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20517325

RESUMO

OBJECTIVES: We investigated the correlation between Japanese apricot (JA) intake and Helicobacter pylori-related chronic atrophic gastritis (CAG). METHODS: A questionnaire was administered and serum anti-H. pylori IgG antibodies measured in 1358 asymptomatic adults. The subjects were divided into high-intake and low-intake groups. Histological and serological evaluation of H. pylori-related CAG was performed in 68 non-elderly volunteers. RESULTS: The H. pylori-negative rate did not differ significantly between the high-intake and low-intake groups. Mean antibody titers were lower in the high-intake group, but the difference was not significant. There was no significant difference in the rate of H. pylori infection on the basis of JA intake when subjects were stratified by age. Among H. pylori-positive non-elderly subjects, antibody titers were significantly lower in the high-intake group (P=0.041). Endoscopic tissue biopsy from the 68 volunteers showed less H. pylori bacterial load and mononuclear infiltration irrespective of gastric site in the high-intake group. In the high-intake group, antral neutrophil infiltration was significantly less pronounced and corporal atrophy was less extensive. Serological evaluation using serum PG levels also confirmed these histopathological data. CONCLUSIONS: Our findings strongly indicate a preventive effect of JA intake on CAG by inhibiting H. pylori infection and reducing active mucosal inflammation.


Assuntos
Dieta , Gastrite/prevenção & controle , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Preparações de Plantas/uso terapêutico , Prunus , Estômago/efeitos dos fármacos , Adulto , Idoso , Anticorpos/sangue , Doença Crônica , Relação Dose-Resposta a Droga , Feminino , Frutas , Gastrite/imunologia , Gastrite/microbiologia , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/efeitos dos fármacos , Pepsinogênio C/sangue , Preparações de Plantas/farmacologia , Prevalência , Estômago/imunologia , Estômago/microbiologia , Inquéritos e Questionários
5.
J Craniomaxillofac Surg ; 38(8): 571-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20381369

RESUMO

BACKGROUND: Several studies have reported certain bone morphogenic proteins (BMPs) to have positive effects on bone generation. Although some investigators have studied the effects of human recombinant BMP (rhBMP-2) in sinus augmentation in sheep, none of these studies looked at the placement of implants at the time of sinus augmentation. Furthermore, no literature could be found to report on the impact that different implant systems, as well as the positioning of the implants had on bone formation if rhBMP-2 was utilized in sinus-lift procedures. PURPOSE: The aim of this study was to compare sinus augmentation with rhBMP-2 on a poly-d, l-lactic-co-glycolic acid gelatine (PLPG) sponge with sinus augmentation with autologous pelvic cancellous bone in the maxillary sinus during the placement of different dental implants. MATERIALS AND METHODS: Nine adult female sheep were submitted to bilateral sinus-floor elevation. In one side (test group) the sinus lift was performed with rhBMP-2 on a PLPG-sponge, while the contralateral side served as the control by using cancellous bone from the iliac crest. Three different implants (Bränemark(®), 3i(®) and Straumann(®)) were inserted either simultaneously with the sinus augmentation or as a two staged procedure 6 weeks later. The animals were sacrificed at 6 and 12 weeks for histological and histomorphometrical evaluations during which bone-to-implant contact (BIC) and bone density (BD) were evaluated. RESULTS: BD and BIC were significantly higher at 12 weeks in the test group if the implants were placed at the time of the sinus lift (p<0.05). No difference was observed between the different implant systems or positions. CONCLUSIONS: The use of rhBMP-2 with PLPG-sponge increased BIC as well as BD in the augmented sinuses if compared to autologous bone. Different implant systems and positions of the implants had no effect on BIC or BD.


Assuntos
Implantes Absorvíveis , Aumento do Rebordo Alveolar/métodos , Densidade Óssea/efeitos dos fármacos , Proteína Morfogenética Óssea 2/farmacologia , Osseointegração/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 2/administração & dosagem , Transplante Ósseo , Implantes Dentários , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Feminino , Esponja de Gelatina Absorvível , Humanos , Seio Maxilar/cirurgia , Procedimentos Cirúrgicos Pré-Protéticos Bucais/métodos , Osteogênese/efeitos dos fármacos , Proteínas Recombinantes , Ovinos
7.
Heart ; 92(4): 515-20, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15994912

RESUMO

OBJECTIVE: To examine the effects of microbubble destruction with ultrasound (MB) combined with bone marrow derived mononuclear cell transplantation (BMT) into ischaemic tissues in rat hind limb ischaemia. METHODS AND RESULTS: Unilateral hind limb ischaemia was surgically induced in Lewis rats. At postoperative day 7, rats were randomly divided into three groups: a vehicle treated group, an ultrasound treated group, and an MB treated group. MB treatment increased vascular endothelial growth factor mRNA as assessed by real time polymerase chain reaction (3.0-fold, p < 0.05). At four weeks, the MB group had increases in laser Doppler blood flow index (LDBFI; 1.2-fold, p < 0.05), angiographically detectable collateral vessels (angiographic score: 1.4-fold, p < 0.01), and capillary to muscle fibre ratio (1.4-fold, p < 0.01) in ischaemic limbs compared with the vehicle treated group. No differences were seen between the vehicle and ultrasound treated groups. Secondly, rats were allocated to vehicle treatment, BMT (5 x 10(6) cells/rat), or a combination of MB and BMT (MB+BMT) at seven days after hind limb ischaemia. BMT treatment significantly increased LDBFI, angiographic score, and capillary to muscle fibre ratio compared with vehicle treatment. Interestingly, MB+BMT treatment produced significantly greater LDBFI (1.2-fold, p < 0.01), angiographic score (1.5-fold, p < 0.01), and capillary to muscle fibre ratio (1.5-fold, p < 0.05) than BMT treatment alone. CONCLUSIONS: MB may be a useful technique to enhance BMT induced neovascularisation.


Assuntos
Transplante de Medula Óssea/métodos , Isquemia/terapia , Microbolhas , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Animais , Membro Posterior/irrigação sanguínea , Membro Posterior/patologia , Imuno-Histoquímica , Isquemia/diagnóstico por imagem , Masculino , Músculo Esquelético/patologia , Distribuição Aleatória , Ratos , Ratos Endogâmicos Lew , Ultrassonografia
8.
Endoscopy ; 36(7): 579-83, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15243878

RESUMO

BACKGROUND AND STUDY AIMS: One of the major complications of endoscopic mucosal resection (EMR) for gastrointestinal tumors is perforation, and the most effective way of preventing perforation is to elevate the lesion sufficiently by endoscopic injection of fluid into the submucosa. MATERIALS AND METHODS: In order to compare the lesion-lifting properties of several different solutions, 1 ml of each of the following solutions was injected into the submucosa of the resected porcine stomach: normal saline, 3.75 % NaCl, 20 % dextrose water, 10 % glycerin with 0.9 % NaCl plus 5 % fructose, and two sodium hyaluronate (SH) solutions. RESULTS: Significantly higher initial elevation was produced by both SH solutions, and it remained higher than that achieved by the other solutions at all times. Hypertonic solutions, especially 10 % glycerin with 0.9 % NaCl plus 5 % fructose, tended to produce and maintain greater mucosal elevation than normal saline, but the difference was not significant. CONCLUSIONS: SH solutions were the most suitable ones for producing and maintaining long-term mucosal elevation, while the superiority of hypertonic solutions over normal saline was not clearly demonstrated.


Assuntos
Mucosa Gástrica/cirurgia , Gastroscopia , Soluções/administração & dosagem , Animais , Mucosa Gástrica/patologia , Gastroscopia/métodos , Glucose , Glicerol , Ácido Hialurônico , Técnicas In Vitro , Injeções , Cloreto de Sódio , Suínos
9.
Endoscopy ; 36(7): 584-9, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15243879

RESUMO

BACKGROUND AND STUDY AIMS: Sodium hyaluronate (SH) is a promising submucosal injection solution during endoscopic mucosal resection, but its high cost is an obstacle to more widespread use. The aim of this study was to identify an appropriate low-cost SH solution by varying the molecular weight of SH and mixing various solutions with it. MATERIALS AND METHODS: The viscoelasticity of various SH solutions was first measured. The concentrations of two 1 % SH preparations with different molecular weights (800 kDa and 1900 kDa) were adjusted to 0.5 %, 0.25 %, and 0.125 %, using 0.9 %/3.75 % normal saline (NS), 5 %/20 % dextrose water (DW), and a glycerin solution (Glyceol): 10 % glycerin with 0.9 % normal saline plus 5 % fructose. The ability of these SH solutions to create submucosal fluid cushions (SFCs) was then investigated in the stomachs of two live minipigs. RESULTS: The 0.25 % 1900 kDa SH/NS solution and the 0.125 % 1900 kDa SH/20 % DW solution created a similar viscoelasticity to that of the 0.5 % 800 kDa SH/NS solution. The ability of these solutions to create SFCs was also similar. In addition, the 0.125 % 1900 kDa SH/Glyceol solution created similar SFCs, with a synergistic effect of increased viscoelasticity and the hypertonic nature of glycerin. CONCLUSIONS: A mixture of higher molecular weight sodium hyaluronate with a sugar solution (particularly 20 % dextrose), with or without glycerin, should be regarded as a cost-effective option for creating SFCs instead of the conventional SH solution made with the same amount of a 1 % 800 kDa SH preparation and normal saline.


Assuntos
Mucosa Gástrica/cirurgia , Gastroscopia , Ácido Hialurônico/administração & dosagem , Injeções , Animais , Mucosa Gástrica/patologia , Gastroscopia/métodos , Glucose , Glicerol , Peso Molecular , Cloreto de Sódio , Soluções/administração & dosagem , Suínos , Porco Miniatura , Viscosidade
10.
Kyobu Geka ; 57(6): 477-80, 2004 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-15202268

RESUMO

A 66-year-old man with left main trunk disease was treated under a diagnosis of acute myocardial infarction based on coronary angiography by off-pump coronary artery bypass (OPCAB). About 1 month after operation, his renal function deteriorated and purpura appeared on both feet, especially at the toe tips. In this case, steroid therapy was performed and the patient survived. Cholesterol embolism rarely occurs after angiographic procedure or cardiovascular surgery. In general, it is associated with high morbidity and mortality, but no optimal treatment has yet been developed. This underlines the importance of careful observation and skin biopsy for early diagnosis.


Assuntos
Síndrome do Artelho Azul/etiologia , Ponte de Artéria Coronária/métodos , Embolia de Colesterol/etiologia , Complicações Pós-Operatórias , Idoso , Angioplastia Coronária com Balão , Síndrome do Artelho Azul/patologia , Humanos , Balão Intra-Aórtico , Masculino , Infarto do Miocárdio/cirurgia , Infarto do Miocárdio/terapia
12.
Int J Oral Maxillofac Surg ; 32(5): 508-14, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14759110

RESUMO

An experimental model for the prefabrication of a vascularized bone flap was developed in this study. To form vascularized bone in the desired configuration and to increase the survival rate of the grafted bone, a muscle vascularized pedicle (MVP) was transformed into vascularized bone by the inducer recombinant human bone morphogenetic protein 2 (rhBMP-2). The muscle flap (8 x 8 mm) raised on saphenous vessels in the rat thigh was sandwiched between same-size collagen (Terudermis) sheets in the presence or absence of impregnated 25 microg of rhBMP-2 for the experimental group and the control group, respectively. The flaps were harvested 1, 2 and 3 weeks postoperatively. Bone transformation was detected by gross examination, radiology, and histologic testing. No evidence of muscle tissue transformation was found in control flaps, whereas all of the experimental flaps produced new bone. Saphenous vessels were observed to supply the new bone upon harvesting, and the newly formed vascularized bone showed good configuration with shape of the Terudermis sheet. This study indicates that this model of effective bone reconstruction could be potentially applied in a therapeutic setting.


Assuntos
Desenvolvimento Ósseo/fisiologia , Proteínas Morfogenéticas Ósseas/metabolismo , Transplante Ósseo/métodos , Músculo Esquelético/fisiologia , Osteogênese/fisiologia , Retalhos Cirúrgicos , Fator de Crescimento Transformador beta , Animais , Proteína Morfogenética Óssea 2 , Transplante Ósseo/fisiologia , Colágeno/fisiologia , Humanos , Masculino , Ossificação Heterotópica/induzido quimicamente , Ratos , Ratos Wistar , Proteínas Recombinantes , Retalhos Cirúrgicos/irrigação sanguínea , Coleta de Tecidos e Órgãos/métodos
13.
Int J Oral Maxillofac Surg ; 32(5): 563-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14759120

RESUMO

Oncocytoma is a rare salivary gland tumour consisting of oncocytes with many hyperplastic mitochondria. It usually occurs in the parotid gland. Because the features of oncocytoma resemble those of other benign and low-grade-malignant salivary gland tumours, clinical diagnosis is often challenging. This report presents the pathologic and imaging findings of an oncocytoma arising in the deep lobe of the left parotid gland in a 66-year-old man. Oncocytoma was diagnosed on the basis of histological, magnetic resonance imaging, and scintigraphic findings. The tumour showed accumulation of technetium-99m pertechnetate and decreased signal intensity on both T1- and T2-weighted magnetic resonance images.


Assuntos
Adenoma Oxífilo/patologia , Neoplasias Parotídeas/patologia , Adenoma Oxífilo/diagnóstico por imagem , Adenoma Oxífilo/cirurgia , Idoso , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Parotídeas/diagnóstico por imagem , Neoplasias Parotídeas/cirurgia , Cintilografia , Compostos Radiofarmacêuticos , Pertecnetato Tc 99m de Sódio
15.
Int J Oral Maxillofac Surg ; 31(3): 287-95, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12190136

RESUMO

The purpose of this study was to evaluate the long-term functional properties of regenerated bone induced by recombinant human bone morphogenetic protein-2 (rhBMP-2) in segmental bone defects of primate mandibles. The 30-mm defects were created in the mandibles of six young monkeys and the mandibles were fixed with titanium plates. Then 9 mg of rhBMP-2 permeating a poly-D, L-lactic-co-glycolic acid-coated gelatin sponge (PGS) was implanted into the bone defect. Dental implants were placed into the regenerated mandible 20 weeks after surgery, then suprastructures were placed and masticatory force loading was begun 8 weeks after the insertion of the dental implants. Bone formation and the quality of new bone were evaluated radiologically and histologically at 15 and 30 weeks after surgery, and 4 and 24 weeks after masticatory force loading. The resected mandibles were completely regenerated with the rhBMP-2-induced bone. Excellent remodelling and consolidation of new bone were observed after loading. This study demonstrated that the new bone induced by rhBMP-2 in large segmental defects was maintained and functional for at least 1 year. Bone regeneration induced by rhBMP-2 holds promise as a future therapy and may be an effective alternative to autogenous bone grafts for implant dentistry and reconstructive surgery.


Assuntos
Proteínas Morfogenéticas Ósseas/farmacologia , Regeneração Óssea/efeitos dos fármacos , Mandíbula/cirurgia , Procedimentos Cirúrgicos Pré-Protéticos Bucais , Fator de Crescimento Transformador beta , Implantes Absorvíveis , Animais , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/administração & dosagem , Placas Ósseas , Implantes Dentários , Prótese Dentária Fixada por Implante , Análise do Estresse Dentário , Implantes Experimentais , Ácido Láctico , Macaca mulatta , Masculino , Mandíbula/fisiologia , Prótese Mandibular , Mastigação , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia
16.
Int J Oral Maxillofac Surg ; 31(1): 66-72, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11936403

RESUMO

This study was designed to evaluate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with poly D, L lactic-co-glycolic acid (PLGA)/gelatin sponge complex (PGS) on the formation of bone in critically sized marginal defects of the mandible in dogs. Three months after extraction of the pre-molar teeth, rectangular bone defects (10 x 8 x 7 mm) were made in both sides of the mandible. A PGS block soaked in rhBMP-2 (400 microgram/ml) was implanted into one defect (BMP (+) group). As control, an untreated PGS block was implanted into the contralateral defect (BMP (-) group). 2, 4, 8, and 12 weeks after implantation, the defects were examined. In the BMP (+) group, newly formed bone was found in all defects from 4 weeks onward and was marked at 12 weeks. In contrast, the BMP (-) group showed no appreciable new bone formation, even at 12 weeks. Moreover, density of newly formed bone in the BMP (+) group was similar to that of the surrounding cortical bone at 12 weeks. These findings suggest that rhBMP-2/PGS is an effective bone substitute for reconstructive surgery of the dog mandible.


Assuntos
Aumento do Rebordo Alveolar/métodos , Proteínas Morfogenéticas Ósseas/farmacologia , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos , Fator de Crescimento Transformador beta , Implantes Absorvíveis , Animais , Materiais Biocompatíveis , Densidade Óssea , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/administração & dosagem , Cães , Gelatina , Humanos , Ácido Láctico , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros , Radiografia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia
17.
Br J Oral Maxillofac Surg ; 39(6): 452-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11735142

RESUMO

The efficacy of bone morphogenetic protein (BMP) for bone reconstruction has been widely studied in numerous animal experiments, but insufficient information exists about its ability to regenerate bone in primates. The purpose of this study was to evaluate the effects of recombinant human BMP-2 (rhBMP-2) on bone formation in alveolar bone defects in the mandibles of young primates. Marginal bone defects were created in the mandibles of nine 5-year-old rhesus monkeys and rhBMP-2 permeated in a polylactic-co-glycolic acid-coated gelatin sponge (PGS) was implanted into the bone defects. The resected bone treated with rhBMP-2 regenerated completely at 12 weeks postoperatively, and remodelling and consolidation of new bone were seen histologically. This study provides evidence of considerable bone regeneration in alveolar defects after surgical implantation of rhBMP-2 in non-human primates. This technique may be an effective alternative to autogenous bone grafts for reconstructive surgery in clinical practice.


Assuntos
Perda do Osso Alveolar/cirurgia , Proteínas Morfogenéticas Ósseas/farmacologia , Regeneração Óssea/efeitos dos fármacos , Procedimentos Cirúrgicos Bucais/métodos , Implantes Absorvíveis , Animais , Densidade Óssea , Proteínas Morfogenéticas Ósseas/administração & dosagem , Humanos , Ácido Láctico , Macaca mulatta , Masculino , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros , Proteínas Recombinantes/farmacologia , Tomografia Computadorizada por Raios X/métodos
19.
EMBO J ; 20(21): 6028-36, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11689443

RESUMO

Apoptosis signal-regulating kinase 1 (ASK1) is a MAP kinase kinase kinase (MAPKKK) that activates the JNK and p38 MAP kinase cascades and is activated in response to oxidative stress such as hydrogen peroxide (H(2)O(2)). A yeast two-hybrid screening identified a serine/threonine protein phosphatase 5 (PP5) as a binding partner of ASK1. PP5 directly dephosphorylated an essential phospho-threonine residue within the kinase domain of ASK1 and thereby inactivated ASK1 activity in vitro and in vivo. The interaction between PP5 and ASK1 was induced by H(2)O(2) treatment and was followed by the decrease in ASK1 activity. PP5 inhibited not only H(2)O(2)-induced sustained activation of ASK1 but also ASK1-dependent apoptosis. Thus, PP5 appears to act as a physiological inhibitor of ASK1-JNK/p38 pathways by negative feedback.


Assuntos
Retroalimentação Fisiológica/fisiologia , MAP Quinase Quinase Quinases/metabolismo , Proteínas Nucleares/metabolismo , Estresse Oxidativo/fisiologia , Fosfoproteínas Fosfatases/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células COS , Linhagem Celular , Células HeLa/enzimologia , Humanos , Peróxido de Hidrogênio/farmacologia , Rim/citologia , Rim/metabolismo , MAP Quinase Quinase Quinase 5 , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/genética , Proteínas Nucleares/genética , Proteínas Nucleares/farmacologia , Oxidantes/farmacologia , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/farmacologia , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Transdução de Sinais/fisiologia , Transfecção , Fator de Necrose Tumoral alfa/farmacologia , Técnicas do Sistema de Duplo-Híbrido
20.
Plast Reconstr Surg ; 108(4): 952-8, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11547152

RESUMO

In this study, an attempt was made to transform a muscle vascularized pedicle raised on host vessels into a vascularized bone flap, using recombinant human bone morphogenetic protein 2 (rhBMP-2). The purpose of this study was to produce new bone vascularized in nature to increase the survival rate of the subsequently grafted bone and to fabricate the newly formed bone into the desired shape. Silicone molds in the shape of a rat mandible were used to deliver rat bone matrix impregnated with or without rhBMP-2. A muscle pedicle the same size as the mold was raised on the saphenous vessels in the rat thigh and then sandwiched in the center of the silicone molds. The molds were sliced in half and each section was filled with rat bone matrix that was impregnated either with 25 microg of rhBMP-2 for the experimental group or with diluting material alone for the control group. The sandwiched flaps were then secured by tying them to the adjacent muscles and were harvested at 2 and 4 weeks after surgery. Three and six rats were used in the control and experimental groups at each time point, respectively. Bone formation was assessed in the ex vivo specimens by macroscopic, radiologic, and histologic evaluation. Macroscopically, the continuation of the vascular pedicle was clearly visible for both the control and experimental muscle flaps. However, no evidence of muscle-tissue transformation was observed in the control flaps, whereas all the flaps treated with rhBMP-2 produced new bone that replicated the shape of the mold exactly and had saphenous vessels supplying the newly formed bone. This study demonstrates that this experimental model has the potential to be therapeutically applied for effective bone reconstruction.


Assuntos
Proteínas Morfogenéticas Ósseas , Osso e Ossos/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos , Fator de Crescimento Transformador beta , Animais , Materiais Biocompatíveis , Proteína Morfogenética Óssea 2 , Masculino , Ratos , Ratos Wistar
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