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1.
J Craniofac Surg ; 32(3): 1147-1149, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33252523

RESUMO

ABSTRACT: In principle, reconstruction in macrostomia requires symmetry and accurate positioning of the newly reconstructed commissure. The proper position of the new commissure can be determined by several methods. In the determination of the new commissure of bilateral cases, generally the average length of the lips or the distance from anatomical landmarks other than the lips, such as the pupils or tragi, has been used. A new approach was reported by Tse et al in 2018: the anatomic approximation approach. Macrostomia repair refers to anatomical landmarks in the lips to determine the new commissure. The authors performed surgery using this anatomic approximation approach for bilateral macrostomia and achieved the good results.


Assuntos
Macrostomia , Cabelo , Humanos , Lábio/cirurgia , Pupila , Couro Cabeludo
2.
J Toxicol Sci ; 45(1): 25-35, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31932555

RESUMO

In this study, we found that nuclear receptors FXR and LXR (originally characterized as regulatory factors involved in cholesterol/bile acid homeostasis) regulate the expression of Oct3/4, a marker for cell differentiation, in both normal renal-derived cell line HK-2 and renal adenocarcinoma cell line ACHN. Down-regulation of Oct3/4 expression by activating FXR and LXR occurs only in normal renal cell-derived HK-2 cells. We also found that the RNA-binding protein, ELAVL2, oppositely regulates Oct3/4 expressions in HK-2 and ACHN cells. Moreover, we revealed that LXR-alpha and LXR-beta regulate each other's expression. Although an LXR-beta-specific agonist is assumed to be the basis for an anti-arteriosclerotic drug that only stimulates reverse cholesterol transport, our findings show that the development of such an anti-arteriosclerotic drug would require further elucidation of the complex mechanism of LXR-alpha and LXR-beta regulation.


Assuntos
Adenocarcinoma , Regulação da Expressão Gênica , Neoplasias Renais , Rim/citologia , Receptores X do Fígado/genética , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Arteriosclerose/tratamento farmacológico , Linhagem Celular , Colesterol/metabolismo , Regulação para Baixo , Descoberta de Drogas , Proteína Semelhante a ELAV 2/genética , Humanos
3.
J Toxicol Sci ; 43(12): 711-715, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30518708

RESUMO

SIRT1, an NAD+-dependent deacetylase, causes deacetylation and down-regulation of its target p53. Given that p53 is an upstream regulator of the transcription of the cyclin-dependent kinase inhibitor p21/Cip1, SIRT1 is hypothesized to play a stimulatory role in carcinoma cell proliferation. We previously reported that down-regulation of SIRT1 caused the increase in p21/Cip1 in a post-transcriptional manner, suggesting that p53 is not involved in the p21/Cip1 increase and raising the question whether SIRT1 exhibits the activity other than deacetylase. In the present study, we examined whether SIRT1 down-regulation and the inhibitor for SIRT1 deacetylase activity affects p21/Cip1 and p53 expression in renal adenocarcinoma cells and normal renal cells. SIRT1 knockdown caused an increase in p53 and p21/Cip1 protein levels in renal adenocarcinoma ACHN cells but not normal renal-derived HK-2 cells. The increase in p53 in ACHN cells is unlikely to contribute to the upregulation of p21/Cip1 expression, given that SIRT1 knockdown did not increase p21/Cip1 mRNA levels in these cells. In contrast to the SIRT1-knock down assay, SIRT1 deacetylase inhibitor did not affect p53 or p21/Cip1 protein levels in ACHN cells. Therefore, SIRT1-knockdown likely stimulates p53 and p21/Cip1 protein expression in a deacetylase-independent manner.


Assuntos
Carcinoma de Células Renais/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Rim/metabolismo , Sirtuína 1/genética , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , Técnicas de Silenciamento de Genes , Humanos , RNA Mensageiro/metabolismo , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53/genética , Regulação para Cima
4.
J Nat Med ; 72(1): 342-346, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29159687

RESUMO

The spirostanol saponin AU-1 from Agavaceae plants stimulates the expression of the glycolytic enzyme phosphoglycerate mutase (PGAM) in ACHN cells. We hypothesized that this may arise from the downregulation of the NAD+-dependent deacetylase SIRT1. In this article, we showed that, unlike in renal adenocarcinoma cells, AU-1 does not affect the expression of SIRT1 in the normal renal cell-derived cell line HK-2. Consistent with the lack of a downregulation of SIRT1, AU-1 did not upregulate, but rather decreased PGAM expression. Moreover, AU-1 inhibited the increase in PGAM levels that results from the knock-down of SIRT1. Our results suggest that AU-1 may prevent carcinogenesis caused by increased cellular PGAM.


Assuntos
Anticarcinógenos/farmacologia , Asparagaceae/química , Fosfoglicerato Mutase/genética , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Espirostanos/farmacologia , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo , Repressão Enzimática , Expressão Gênica/efeitos dos fármacos , Glicólise , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfoglicerato Mutase/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo
5.
J Toxicol Sci ; 42(3): 259-265, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28496032

RESUMO

The farnesoid X receptor (FXR) is a bile acid-activated nuclear receptor which is abundant in the liver, intestine, and kidney. FXR is a pivotal factor in cholesterol/bile acid homeostasis but is involved in the growth of hepatocellular carcinoma cells. In the present study, we investigated whether FXR is also involved in the growth of renal adenocarcinoma cells. The cell growth of renal adenocarcinoma cell line ACHN was inhibited by FXR knockdown and stimulated by FXR ligand, while that of a normal renal cell-derived cell line, HK-2, was not affected. The carcinoma-specific stimulation of cell growth by FXR was found to arise from down-regulation of p53 and p21/Cip1 mRNA expression. Our study showed that FXR stimulates proliferation of renal adenocarcinoma cells and that FXR knockdown is useful for growth suppression of renal adenocarcinoma without cytotoxicity to normal renal cells.


Assuntos
Adenocarcinoma/patologia , Processos de Crescimento Celular/genética , Transformação Celular Neoplásica/genética , Neoplasias Renais/patologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Adulto , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação para Baixo , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Ligantes , Masculino , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/genética , Adulto Jovem
6.
Int J Food Sci Nutr ; 67(2): 99-110, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26883301

RESUMO

Development of type 2 diabetes mellitus and insulin resistance is associated with a quality of dietary fatty acids such as saturated and unsaturated fatty acids. Dietary fatty acids also include transform of unsaturated fatty acids and intake of transform of oleate (elaidate) is associated with cardiovascular disease. However, little is known about the roles of elaidate in insulin responsiveness. We show here that elaidate impairs insulin-dependent glucose uptake in adipocytes. Differentiation with 10 µM elaidate, which is close to physiological plasma concentration, reduces insulin-dependent glucose uptake. Furthermore, insulin-dependent GLUT4 translocation is disturbed in adipocytes differentiated with elaidate. In addition, analysis of lipolysis and gene expression shows that deteriorative effects of elaidate on insulin responsiveness are limited but not general. Thus, our findings reveal that differentiation with elaidate tends to affect insulin-dependent glucose uptake through alternation of GLUT4 translocation from cytosol to the plasma membrane.


Assuntos
Adipócitos/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Ácido Oleico/farmacologia , Células 3T3-L1 , Adipócitos/fisiologia , Animais , Diferenciação Celular , Ácidos Graxos/química , Regulação da Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 4/genética , Camundongos , Ácidos Oleicos , Soroalbumina Bovina/química
7.
J Oral Maxillofac Surg ; 72(3): 485-95, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24528562

RESUMO

PURPOSE: Novel gabapentin-lactam (GBP-L) has shown its potency in enhancing new bone formation (NBF) in vitro. The objective of the present preclinical trial was to investigate the in vivo performance of GBP-L. MATERIALS AND METHODS: Bilateral sinus floor augmentations in 10 adult sheep were conducted. Bovine bone mineral (BBM) and mesenchymal stem cells (MSCs) combined with novel GBP-L were placed into the test sinus of each sheep. The BBM and MSCs alone served as the control on the contralateral side. Simultaneously, 3 dental implants were inserted in each maxillary sinus. The animals were sacrificed after 8 and 16 weeks, and the amount of NBF was analyzed using histomorphometry. The osteogenic potency of the MSCs was demonstrated using the colony-forming unit and differentiation assay. Statistical evaluation was performed using the Wilcoxon signed rank test and 3-factorial nonparametric analysis of variance. RESULTS: The histologic examination showed NBF in tight contact with the original bone in the control and test groups. The NBF was not significantly different between the test and control sites (P > .05). However, a highly significant difference in NBF between the apical and coronal sites in the specimens from the control and test groups was detected (P < .05). GBP-L did not alter the multipotency of the MSCs or impair NBF. CONCLUSIONS: Bone formation is initiated from the residual alveolar crest and along the implant. The elected mode of GBP-L application did not induce faster NBF. Alternate forms of application (eg, slow release or systemic administration) might clarify the controversial in vitro findings.


Assuntos
Aumento do Rebordo Alveolar/métodos , Compostos Aza/farmacologia , Regeneração Óssea/efeitos dos fármacos , Implantação Dentária Endóssea/métodos , Maxila/efeitos dos fármacos , Transplante de Células-Tronco Mesenquimais , Levantamento do Assoalho do Seio Maxilar/métodos , Compostos de Espiro/farmacologia , Animais , Substitutos Ósseos , Diferenciação Celular , Proliferação de Células , Ensaio de Unidades Formadoras de Colônias , Feminino , Osseointegração , Ovinos
8.
Int J Oral Maxillofac Implants ; 29(1): e73-80, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24451891

RESUMO

PURPOSE: Modern bone tissue engineering associated with mesenchymal stem cells (MSCs) provides promising treatment alternatives for the loss of bone, one of the foremost challenges in oral and craniofacial surgery today. The effect of gabapentin-lactam (GBP-L) and its analogs on osteogenic differentiated MSCs has not yet been deciphered. Consequently, this study investigates the effect of novel trans-8-tertbutylgabapentin-lactam (trans-8-TB-GBP-L) hydroxamic acid derivatives on metabolism, proliferation, and physiologic mineralization characteristics of ovine osteoblast cells. MATERIALS AND METHODS: Osteoblasts were extracted and prepared from sheep femoral heads and cultured in medium enriched with hydroxamic acid derivatives of trans-8-TB-GBP-L. The cell proliferation rate, cell metabolism, cell viability, and basic osteoblastic function were assessed. RESULTS: After 3 and 5 days of incubation, no significant increase in DNA content was detected in any of 12 test groups versus the control group. However, after 8 days of incubation, a significant increase of DNA contents in the test groups containing nanomolar concentrations of trans-8-TB-GBP-L hydroxamic acid derivatives was found. No significant aberration in metabolic activity was detected when any of the test substances were applied. ALP displayed similar activity rates among the test groups and the control at all time points. Calcification of osteoblastic cells occurred solely when nanomolar concentrations were used. CONCLUSION: Trans-8-TB-GBP-L hydroxamic acid derivatives do not interfere with physiologic function and phenotype of ovine osteoblasts. However, when applied at nanomolar concentrations, the assessed GBP-L derivatives significantly increased the cell proliferation rate after 8 days of incubation, indicating a dose-response curve with the maximum peak at nanomolar concentration and a retarded drug response between 5 and 8 days.


Assuntos
Compostos Aza/farmacologia , Proliferação de Células/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Compostos de Espiro/farmacologia , Engenharia Tecidual/métodos , Animais , Reabsorção Óssea/terapia , Osso e Ossos , Calcificação Fisiológica , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteoblastos/metabolismo , Fenótipo , Ovinos
9.
Int J Oral Maxillofac Implants ; 28(5): e310-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24066349

RESUMO

PURPOSE: Following initial positive reports of the use of bone marrow aspirate concentrate (BMAC) in combination with bovine bone mineral (BBM) in augmentation procedures, the technique was evaluated in patients with mandibular deficiency. MATERIALS AND METHODS: Two adult patients required surgical correction of a deficient alveolar ridge (one patient showed horizontal deficiency only, and the other patient presented with horizontal and vertical deficiency) prior to dental implant placement. In both patients, the reconstruction was performed with BBM in combination with mononuclear cells concentrated by the BMAC method using different techniques. RESULTS: The patients recovered well from all surgical procedures. Histologically, there was uniform bone formation, which allowed placement of dental implants. CONCLUSION: The results suggest that the use of BMAC in combination with BBM, without autogenous bone, has the potential to restore horizontal and vertical mandibular alveolar defects, providing a functional bone structure and allowing dental implant placement for subsequent prosthetic rehabilitation.


Assuntos
Aumento do Rebordo Alveolar/métodos , Transplante de Medula Óssea/métodos , Implantação Dentária Endóssea/métodos , Reconstrução Mandibular/métodos , Adulto , Processo Alveolar/cirurgia , Animais , Medula Óssea , Bovinos , Separação Celular/métodos , Feminino , Humanos , Masculino , Mandíbula/cirurgia , Pessoa de Meia-Idade , Minerais , Osteogênese
10.
Tissue Eng Part A ; 17(17-18): 2187-97, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21529247

RESUMO

PURPOSE: The purpose of this work was to evaluate the potential of substituting autogenous bone (AB) by bone marrow aspirate concentrate (BMAC). Both AB and BMAC were tested in combination with a bovine bone mineral (BBM) for their ability of new bone formation (NBF) in a multicentric, randomized, controlled, clinical and histological noninferiority trial. MATERIALS AND METHODS: Forty-five severely atrophied maxillary sinus from 26 patients were evaluated in a partial cross-over design. As test arm, 34 sinus of 25 patients were augmented with BBM and BMAC containing mesenchymal stem cells. Eleven control sinus from 11 patients were augmented with a mixture of 70% BBM and 30% AB. Biopsies were obtained after a 3-4-month healing period at time of implant placement and histomorphometrically analyzed for NBF. RESULTS: NBF was 14.3%±1.8% for the control and nonsignificantly lower (12.6%±1.7%) for the test (90% confidence interval: -4.6 to 1.2). Values for BBM (31.3%±2.7%) were significantly higher for the test compared with control (19.3%±2.5%) (p<0.0001). Nonmineralized tissue was lower by 3.3% in the test compared with control (57.6%; p=0.137). CONCLUSIONS: NBF after 3-4 months is equivalent in sinus, augmented with BMAC and BBM or a mixture of AB and BBM. This technique could be an alternative for using autografts to stimulate bone formation.


Assuntos
Medula Óssea/metabolismo , Substitutos Ósseos/uso terapêutico , Transplante Ósseo/métodos , Levantamento do Assoalho do Seio Maxilar/métodos , Adulto , Idoso , Animais , Regeneração Óssea/fisiologia , Bovinos , Feminino , Humanos , Masculino , Seio Maxilar/cirurgia , Pessoa de Meia-Idade , Osteogênese/fisiologia , Método Simples-Cego
11.
Biol Pharm Bull ; 34(1): 54-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21212517

RESUMO

FGD1 encodes a guanine nucleotide exchange factor for Cdc42. Mutations in the FGD1 gene are responsible for an X-linked disorder known as Aarskog-Scott syndrome (AAS). While most mutations were found in the catalytic region, which consists of Dbl homology (DH) domain and adjacent pleckstrin homology (PH) domain, a missense mutation in the proline-rich domain is also found in a patient with typical clinical features as AAS. In this mutant FGD1, the serine residue at 205 is replaced with isoleucine. We recently demonstrated that FGD1 translocated to the membrane in response to extracellular stimuli such as epidermal growth factor (EGF) whereas FGD1 with S(205)/I substitution did not. Here we show that the proline-rich domain is critical for FGD1-induced directionally persistent cell migration. When inducibly expressed in HeLa Tet-Off cells, FGD1 stimulates directional migration whereas FGD1 with S(205)/I substitution does not affect it. We further demonstrate that FGD1 augments EGF-stimulated c-Jun NH(2)-terminal kinase (JNK) activation. In the presence of JNK inhibitor SP600125, motility of FGD1-expressing cells is significantly impaired, indicating a critical role of JNK in cell migration. However, FGD3, an FGD1 homologue lacking the proline-rich domain, and FGD1 with S(205)/I substitution augment EGF-stimulated JNK activation similarly to FGD1, suggesting that the proline-rich domain is not involved in the regulation of JNK. Finally, we show that FGD1, but not FGD1 with S(205)/I substitution, is phosphorylated in response to EGF, suggesting that the phosphorylation of S(205) may trigger the FGD1 translocation to the leading edge membrane and enable cells to undergo directional migration.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Movimento Celular , Regulação da Expressão Gênica/fisiologia , Células HeLa , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Transdução de Sinais
12.
Br J Oral Maxillofac Surg ; 49(6): 480-2, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20678831

RESUMO

We report a simplified method of using bone marrow aspirate concentrate (BMAC™) to regenerate hard tissue. The results suggest that BMAC™ combined with a suitable biomaterial can form sufficient bone within 3 months for further implants to be inserted, and at the same time minimise morbidity at the donor site.


Assuntos
Transplante de Medula Óssea/métodos , Regeneração Óssea/fisiologia , Substitutos Ósseos/uso terapêutico , Transplante de Células-Tronco Mesenquimais/métodos , Levantamento do Assoalho do Seio Maxilar/métodos , Materiais Biocompatíveis/uso terapêutico , Humanos , Arcada Parcialmente Edêntula/cirurgia , Masculino , Maxila/cirurgia , Pessoa de Meia-Idade , Osteogênese/fisiologia
13.
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
14.
Tissue Eng Part C Methods ; 16(5): 1033-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20050809

RESUMO

INTRODUCTION: New reconstructive and less invasive methods have been searched to optimize bone formation and osseointegration of dental implants in maxillary sinus augmentation. PURPOSE: The aim of the presented ovine split-mouth study was to compare bovine bone mineral (BBM) alone and in combination with mesenchymal stem cells (MSCs) regarding their potential in sinus augmentation. MATERIAL AND METHODS: Bilateral sinus floor augmentations were performed in six adult sheep. BBM and MSCs were placed into the test side and only BBM in the contra-lateral control side of each sheep. Animals were sacrificed after 8 and 16 weeks. Augmentation sites were analyzed by computed tomography, histology, and histomorphometry. RESULTS: The initial volumes of both sides were similar and did not change significantly with time. A tight connection between the particles of BBM and the new bone was observed histologically. Bone formation was significantly (p = 0.027) faster by 49% in the test sides. CONCLUSION: The combination of BBM and MSCs accelerated new bone formation in this model of maxillary sinus augmentation. This could allow early placement of implants.


Assuntos
Osso e Ossos , Células-Tronco Mesenquimais/citologia , Minerais , Seios Paranasais/cirurgia , Animais , Bovinos , Adesão Celular , Ovinos
15.
Biol Pharm Bull ; 33(1): 35-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20045932

RESUMO

We previously demonstrated that FGD1, the Cdc42 guanine nucleotide exchange factor (GEF) responsible for faciogenital dysplasia, and its homologue FGD3 are targeted by the ubiquitin ligase SCF(FWD1) upon phosphorylation of two serine residues in their DSGIDS motif and subsequently degraded by the proteasome. FGD1 and FGD3 share highly homologous Dbl homology (DH) and adjacent pleckstrin homology (PH) domains, both of which are responsible for GEF activity. However, their function and regulation are remarkably different. Here we demonstrate extracellular signal-responsive translocation of FGD1, but not FGD3. During the wound-healing process, translocation of FGD1 to the leading edge membrane occurs in cells facing to the wound. Furthermore, epidermal growth factor (EGF) stimulates the membrane translocation of FGD1, but not FGD3. As the most striking difference, FGD3 lacks the N-terminal proline-rich domain that is conserved in FGD1, indicating that proline-rich domain may play a crucial role in signal-responsive translocation of FGD1. Indeed, there is a faciogenital dysplasia patient who has a missense mutation in proline-rich domain of FGD1, by which the serine residue at position 205 is substituted with isoleucine. When expressed in cells, the mutant FGD1 with S(205)/I substitution fails to translocate to the membrane in response to the mitogenic stimuli. Thus we present a novel mechanism by which the activity of FGD1, a GEF for Cdc42, is temporally and spatially regulated in cells.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Prolina/metabolismo , Estrutura Terciária de Proteína/fisiologia , Transdução de Sinais/fisiologia , Cicatrização/fisiologia , Transporte Biológico/fisiologia , Membrana Celular/fisiologia , Fatores de Troca do Nucleotídeo Guanina/genética , Células HeLa , Humanos , Isoleucina/metabolismo , Mutação , Serina/metabolismo , Translocação Genética
16.
Br J Oral Maxillofac Surg ; 48(4): 285-90, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19665265

RESUMO

Our aim was to compare the osteogenic potential of mononuclear cells harvested from the iliac crest combined with bovine bone mineral (BBM) (experimental group) with that of autogenous cancellous bone alone (control group). We studied bilateral augmentations of the sinus floor in 6 adult sheep. BBM and mononuclear cells (MNC) were mixed and placed into one side and autogenous bone in the other side. Animals were killed after 8 and 16 weeks. Sites of augmentation were analysed radiographically and histologically. The mean (SD) augmentation volume was 3.0 (1.0) cm(3) and 2.7 (0.3) cm(3) after 8 and 16 weeks in the test group, and 2.8 (0.3) cm(3) (8 weeks) and 2.8 (1.2) cm(3) (16 weeks) in the control group, respectively. After 8 weeks, histomorphometric analysis showed 24 (3)% BBM, and 19 (11)% of newly formed bone in the test group. The control group had 20 (13%) of newly formed bone. Specimens after 16 weeks showed 29 (12%) of newly formed bone and 19 (3%) BBM in the test group. The amount of newly formed bone in the control group was 16 (6%). The results show that mononuclear cells, including mesenchymal stem cells, in combination with BBM as the biomaterial, have the potential to form bone.


Assuntos
Aumento do Rebordo Alveolar/métodos , Matriz Óssea/transplante , Substitutos Ósseos/uso terapêutico , Seio Maxilar/cirurgia , Células-Tronco Mesenquimais/fisiologia , Minerais/uso terapêutico , Animais , Matriz Óssea/patologia , Remodelação Óssea/fisiologia , Bovinos , Contagem de Células , Fluoresceínas , Corantes Fluorescentes , Ósteon/patologia , Maxila/patologia , Maxila/cirurgia , Seio Maxilar/patologia , Osteoclastos/patologia , Osteogênese/fisiologia , Ovinos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Transplante Autólogo , Transplante Heterólogo
17.
Tissue Eng Part C Methods ; 16(2): 215-23, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19473102

RESUMO

OBJECTIVE: To compare new bone formation in maxillary sinus augmentation procedures using biomaterial associated with mesenchymal stem cells (MSCs) separated by two different isolation methods. BACKGROUND: In regenerative medicine open cell concentration systems are only allowed for clinical application under good manufacturing practice conditions. METHODS: Mononuclear cells, including MSCs, were concentrated with either the synthetic polysaccharide (FICOLL) method (classic open system--control group, n = 6 sinus) or the bone marrow aspirate concentrate (BMAC) method (closed system--test group, n = 12 sinus) and transplanted in combination with biomaterial. A sample of the cells was characterized by their ability to differentiate. After 4.1 months (SD +/- 1.0) bone biopsies were obtained and analyzed. RESULTS: The new bone formation in the BMAC group was 19.9% (90% confidence interval [CI], 10.9-29), and in the FICOLL group was 15.5% (90% CI, 8.6-22.4). The 4.4% difference was not significant (90% CI, -4.6-13.5; p = 0.39). MSCs could be differentiated into osteogenic, chondrogenic, and adipogenic lineages. CONCLUSION: MSCs harvested from bone marrow aspirate in combination with bovine bone matrix particles can form lamellar bone and provide a reliable base for dental implants. The closed BMAC system is suited to substitute the open FICOLL system in bone regeneration procedures.


Assuntos
Materiais Biocompatíveis/farmacologia , Extratos Celulares/farmacologia , Ficoll/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Regeneração/fisiologia , Idoso , Aumento do Rebordo Alveolar/instrumentação , Aumento do Rebordo Alveolar/métodos , Animais , Biópsia por Agulha , Células da Medula Óssea/química , Regeneração Óssea/fisiologia , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Bovinos , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Separação Celular/métodos , Implantação Dentária/métodos , Humanos , Implante de Prótese Maxilofacial/métodos , Pessoa de Meia-Idade , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Engenharia Tecidual/métodos , Dente/fisiologia
18.
Genes Cells ; 13(4): 329-42, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18363964

RESUMO

We previously demonstrated that FGD1, the Cdc42 guanine nucleotide exchange factor (GEF) responsible for faciogenital dysplasia, is targeted by the ubiquitin ligase SCF(FWD1/beta-TrCP) upon phosphorylation of two serine residues in its DSGIDS motif and subsequently degraded by the proteasome. Here we show that FGD3, which was identified as a homologue of FGD1 but has been poorly characterized, has conserved the same motif and is down-regulated similarly by SCF(FWD1/beta-TrCP). Although FGD3 and FGD1 share strikingly similar Dbl homology (DH) domains and adjacent pleckstrin homology (PH) domains, both of which are responsible for guanine nucleotide exchange, there also exist remarkable differences in their structures. Indeed, FGD1 and FGD3 induced significantly different morphological changes in HeLa Tet-Off cells: whereas FGD1 induced long finger-like protrusions, FGD3 induced broad sheet-like protrusions when the level of GTP-bound Cdc42 was significantly increased by the inducible expression of FGD3. Furthermore, FGD1 and FGD3 reciprocally regulated cell motility: when inducibly expressed in HeLa Tet-Off cells, FGD1 stimulated cell migration whereas FGD3 inhibited it. Thus we demonstrate that the highly homologous GEFs, FGD1 and FGD3 play different roles to regulate cellular functions but that their intracellular levels are tightly controlled by the same destruction pathway through SCF(FWD1/beta-TrCP).


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Animais , Sequência de Bases , Linhagem Celular , Movimento Celular/fisiologia , Forma Celular/fisiologia , Primers do DNA/genética , Fatores de Troca do Nucleotídeo Guanina/química , Células HeLa , Humanos , Camundongos , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas/antagonistas & inibidores , Proteínas/genética , Proteínas/fisiologia , Interferência de RNA , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Transfecção , Proteína cdc42 de Ligação ao GTP/metabolismo
19.
Biosci Biotechnol Biochem ; 69(8): 1545-54, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16116284

RESUMO

Fatty acid hydroperoxide lyase (HPL), a member of cytochrome P450 (CYP74), produces aldehydes and oxo-acids involved in plant defensive reactions. In monocots, HPL that cleaves 13-hydroperoxides of fatty acids has been reported, but HPL that cleaves 9-hydroperoxides is still unknown. To find this type of HPL, in silico screening of candidate cDNA clones and subsequent functional analyses of recombinant proteins were performed. We found that AK105964 and AK107161 (Genbank accession numbers), cDNAs previously annotated as allene oxide synthase (AOS) in rice, are distinctively grouped from AOS and 13-HPL. Recombinant proteins of these cDNAs produced in Escherichia. coli cleaved both 9- and 13-hydroperoxide of linoleic and linolenic into aldehydes, while having only a trace level of AOS activity and no divinyl ether synthase activity. Hence we designated AK105964 and AK107161 OsHPL1 and OsHPL2 respectively. They are the first CYP74C family cDNAs to be found in monocots.


Assuntos
Carbono-Oxigênio Liases/genética , Sistema Enzimático do Citocromo P-450/genética , DNA Complementar/genética , Oryza/enzimologia , Sequência de Aminoácidos , Sequência de Bases , Carbono-Oxigênio Liases/química , Carbono-Oxigênio Liases/metabolismo , Clonagem Molecular , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Primers do DNA , Escherichia coli/genética , Dados de Sequência Molecular , Oryza/genética , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
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