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1.
Front Immunol ; 15: 1411930, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881891

RESUMO

Introduction: Sepsis is a life-threatening inflammatory condition caused by dysregulated host responses to infection. Extracellular cold-inducible RNA-binding protein (eCIRP) is a recently discovered damage-associated molecular pattern that causes inflammation and organ injury in sepsis. Kupffer cells can be activated and polarized to the inflammatory M1 phenotype, contributing to tissue damage by producing proinflammatory mediators. We hypothesized that eCIRP promotes Kupffer cell M1 polarization in sepsis. Methods: We stimulated Kupffer cells isolated from wild-type (WT) and TLR4-/- mice with recombinant mouse (rm) CIRP (i.e., eCIRP) and assessed supernatant IL-6 and TNFα levels by ELISA. The mRNA expression of iNOS and CD206 for M1 and M2 markers, respectively, was assessed by qPCR. We induced sepsis in WT and CIRP-/- mice by cecal ligation and puncture (CLP) and assessed iNOS and CD206 expression in Kupffer cells by flow cytometry. Results: eCIRP dose- and time-dependently increased IL-6 and TNFα release from WT Kupffer cells. In TLR4-/- Kupffer cells, their increase after eCIRP stimulation was prevented. eCIRP significantly increased iNOS gene expression, while it did not alter CD206 expression in WT Kupffer cells. In TLR4-/- Kupffer cells, however, iNOS expression was significantly decreased compared with WT Kupffer cells after eCIRP stimulation. iNOS expression in Kupffer cells was significantly increased at 20 h after CLP in WT mice. In contrast, Kupffer cell iNOS expression in CIRP-/- mice was significantly decreased compared with WT mice after CLP. CD206 expression in Kupffer cells was not different across all groups. Kupffer cell M1/M2 ratio was significantly increased in WT septic mice, while it was significantly decreased in CIRP-/- mice compared to WT mice after CLP. Conclusion: Our data have clearly shown that eCIRP induces Kupffer cell M1 polarization via TLR4 pathway in sepsis, resulting in overproduction of inflammatory cytokines. eCIRP could be a promising therapeutic target to attenuate inflammation by preventing Kupffer cell M1 polarization in sepsis.


Assuntos
Células de Kupffer , Camundongos Knockout , Proteínas de Ligação a RNA , Sepse , Animais , Células de Kupffer/imunologia , Células de Kupffer/metabolismo , Sepse/imunologia , Sepse/metabolismo , Camundongos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Camundongos Endogâmicos C57BL , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Modelos Animais de Doenças , Inflamação/imunologia , Inflamação/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Receptor de Manose , Interleucina-6/metabolismo
2.
Maxillofac Plast Reconstr Surg ; 45(1): 42, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38108939

RESUMO

Orthognathic surgery, essential for addressing jaw and facial skeletal irregularities, has historically relied on traditional surgical planning (TSP) involving a series of time-consuming steps including two-dimensional radiographs. The advent of virtual surgical planning (VSP) and 3D printing technologies has revolutionized this field, bringing unprecedented precision and customization to surgical processes. VSP facilitates 3D visualization of the surgical site, allowing for real-time adjustments and improving preoperative stress for patients by reducing planning time. 3D printing dovetails with VSP, offering the creation of anatomical models and surgical guides, enhancing the predictability of surgical outcomes despite higher initial setup and material costs. The integration of VSP and 3D printing promises innovative and effective solutions in orthognathic surgery, surpassing the limitations of traditional methods. Patient-reported outcomes show a positive post-surgery impact on the quality of life, underlining the significant role of these technologies in enhancing self-esteem and reducing anxiety. Economic analyses depict a promising long-term fiscal advantage with these modern technologies, notwithstanding the higher initial costs. The review emphasizes the need for large-scale randomized controlled trials to address existing research gaps and calls for a deeper exploration into the long-term impacts and ethical considerations of these technologies. In conclusion, while standing on the cusp of a technological renaissance in orthognathic surgery, it is incumbent upon the medical fraternity to foster a collaborative approach, balancing innovation with scrutiny to enhance patient care. The narrative review encourages the leveraging of VSP and 3D printing technologies for more efficient and patient-centric orthognathic surgery, urging the community to navigate uncharted territories in pursuit of precision and efficiency in the surgical landscape.

3.
Nat Commun ; 13(1): 2708, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577790

RESUMO

Cystinuria is a genetic disorder characterized by overexcretion of dibasic amino acids and cystine, causing recurrent kidney stones and kidney failure. Mutations of the regulatory glycoprotein rBAT and the amino acid transporter b0,+AT, which constitute system b0,+, are linked to type I and non-type I cystinuria respectively and they exhibit distinct phenotypes due to protein trafficking defects or catalytic inactivation. Here, using electron cryo-microscopy and biochemistry, we discover that Ca2+ mediates higher-order assembly of system b0,+. Ca2+ stabilizes the interface between two rBAT molecules, leading to super-dimerization of b0,+AT-rBAT, which in turn facilitates N-glycan maturation and protein trafficking. A cystinuria mutant T216M and mutations of the Ca2+ site of rBAT cause the loss of higher-order assemblies, resulting in protein trapping at the ER and the loss of function. These results provide the molecular basis of system b0,+ biogenesis and type I cystinuria and serve as a guide to develop new therapeutic strategies against it. More broadly, our findings reveal an unprecedented link between transporter oligomeric assembly and protein-trafficking diseases.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos , Cálcio , Cistinúria , Sistemas de Transporte de Aminoácidos/metabolismo , Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Sistemas de Transporte de Aminoácidos Básicos/ultraestrutura , Cálcio/química , Cálcio/metabolismo , Cistina/metabolismo , Cistinúria/genética , Cistinúria/metabolismo , Humanos
4.
Maxillofac Plast Reconstr Surg ; 44(1): 11, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35298724

RESUMO

BACKGROUND: Many studies on maintaining the condyle in a normal or anatomical position during orthognathic surgery have been conducted to stabilize surgical outcomes and prevent iatrogenic temporomandibular joint complications. The aim of this study is to evaluate the changes in condylar positions after orthognathic surgery using virtual surgical planning via the balanced orthognathic surgery (BOS) system. METHODS: Postoperative changes in condylar position were retrospectively evaluated in 22 condyles of 11 patients with skeletal class III malocclusion who underwent orthognathic surgery using virtual surgical planning via the BOS system. The center point coordinates of the condylar head before and after orthognathic surgery were analyzed using voxel-based registration. RESULTS: Changes in the condylar position mainly occurred downward in the y-axis (-1.09 ± 0.62 mm) (P < 0.05). The change in the x-axis (0.02 ± 0.68 mm) and z-axis (0.01 ± 0.48 mm) showed no significant difference between before and after orthognathic surgery. CONCLUSION: These results indicate that the changes in the condylar positions after orthognathic surgery using virtual surgical planning via the BOS system mainly occurred downward in the y-axis, with slight changes in the x- and z-axes. The change in the condylar position after orthognathic surgery using the BOS system is clinically acceptable.

5.
J Oral Maxillofac Surg ; 79(5): 1146.e1-1146.e25, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33539812

RESUMO

PURPOSE: Accuracy in orthognathic surgery with virtual planning has been reported, but detailed analysis of accuracy according to anatomic location, including the mandibular condyle, is insufficient. The purpose of this study was to compare the virtual plan and surgical outcomes and analyze the degree and distribution of errors according to each anatomic location. PATIENTS AND METHODS: This retrospective cohort study evaluated skeletal class III patients, treated with bimaxillary surgery. The primary predictor was anatomic locations that consisted of right and left condyles, maxilla, and the distal segment of the mandible. Other variables were age and gender. The primary outcome was surgical accuracy, defined as mean 3-dimensional distance error, mean absolute error, and mean error along the horizontal, vertical, and anteroposterior axes between the virtual plan and surgical outcomes. Landmarks were compared using a computational method based on affine transformation with a 1-time landmark setting. The mean errors were visualized with multidimensional scattergrams. Bivariate and regression statistics were computed. RESULTS: This study included 52 patients, 26 men and 26 women, with a mean age of 21 years and 3 months. The mean 3D distance errors for condylar landmarks, maxillary landmarks, and landmarks on the distal segment of the mandible were 1.03, 1.25, and 2.24 mm, respectively. Condylar landmarks, maxillary landmarks, and the landmarks on the distal segment of the mandible were positioned at 0.49 mm inferior, 0.28 mm anterior, and 1.25 mm inferior, respectively. The landmark errors for the distal segment of the mandible exhibited a wider distribution than those for condylar and maxillary landmarks. CONCLUSIONS: Agreement between the planned and actual outcome aided by virtual surgical planning was highest for the condyles, followed by the maxilla, and the distal segment of the mandible. It is important to consider the tendency for surgical errors in each anatomic location during operations.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Cirurgia Assistida por Computador , Adulto , Feminino , Humanos , Imageamento Tridimensional , Masculino , Mandíbula , Maxila , Estudos Retrospectivos , Adulto Jovem
6.
Front Immunol ; 12: 780210, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35003095

RESUMO

Extracellular cold-inducible RNA-binding protein (eCIRP) is a damage-associated molecular pattern promoting inflammation and tissue injury. During bacterial or viral infection, macrophages release DNA decorated with nuclear and cytoplasmic proteins known as macrophage extracellular traps (METs). Gasdermin D (GSDMD) is a pore-forming protein that has been involved in extracellular trap formation in neutrophils. We hypothesized that eCIRP induces MET formation by activating GSDMD. Human monocytic cell line THP-1 cells were differentiated with phorbol 12-myristate 13-acetate (PMA) and treated with recombinant murine (rm) CIRP. The MET formation was detected by three methods: time-lapse fluorescence microscopy (video imaging), colorimetry, and ELISA. Cleaved forms of GSDMD, and caspase-1 were detected by Western blotting. Treatment of THP-1 cells with rmCIRP increased MET formation as revealed by SYTOX Orange Staining assay in a time- and dose-dependent manner. METs formed by rmCIRP stimulation were further confirmed by extracellular DNA, citrullinated histone H3, and myeloperoxidase. Treatment of THP-1 cells with rmCIRP significantly increased the cleaved forms of caspase-1 and GSDMD compared to PBS-treated cells. Treatment of macrophages with caspase-1, and GSDMD inhibitors z-VAD-fmk, and disulfiram, separately, significantly decreased rmCIRP-induced MET formation. We also confirmed rmCIRP-induced MET formation using primary cells murine peritoneal macrophages. These data clearly show that eCIRP serves as a novel inducer of MET formation through the activation of GSDMD and caspase-1.


Assuntos
Armadilhas Extracelulares/imunologia , Macrófagos/imunologia , Proteínas de Ligação a Fosfato/imunologia , Proteínas Citotóxicas Formadoras de Poros/imunologia , Proteínas de Ligação a RNA/imunologia , Animais , Células Cultivadas , Armadilhas Extracelulares/metabolismo , Humanos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Ligação a Fosfato/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Proteínas de Ligação a RNA/metabolismo , Células THP-1
7.
Protein Sci ; 29(12): 2398-2407, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33016372

RESUMO

System xc - is an amino acid antiporter that imports L-cystine into cells and exports intracellular L-glutamate, at a 1:1 ratio. As L-cystine is an essential precursor for glutathione synthesis, system xc - supports tumor cell growth through glutathione-based oxidative stress resistance and is considered as a potential therapeutic target for cancer treatment. System xc - consists of two subunits, the light chain subunit SLC7A11 (xCT) and the heavy chain subunit SLC3A2 (also known as CD98hc or 4F2hc), which are linked by a conserved disulfide bridge. Although the recent structures of another SLC7 member, L-type amino acid transporter 1 (LAT1) in complex with CD98hc, have provided the structural basis toward understanding the amino acid transport mechanism, the detailed molecular mechanism of xCT remains unknown. To revealthe molecular mechanism, we performed single-particle analyses of the xCT-CD98hc complex. As wild-type xCT-CD98hc displayed poor stability and could not be purified to homogeneity, we applied a consensus mutagenesis approach to xCT. The consensus mutated construct exhibited increased stability as compared to the wild-type, and enabled the cryoelectron microscopy (cryo-EM) map to be obtained at 6.2 Å resolution by single-particle analysis. The cryo-EM map revealed sufficient electron density to assign secondary structures. In the xCT structure, the hash and arm domains are well resolved, whereas the bundle domain shows some flexibility. CD98hc is positioned next to the xCT transmembrane domain. This study provides the structural basis of xCT, and our consensus-based strategy could represent a good choice toward solving unstable protein structures.


Assuntos
Sistema y+ de Transporte de Aminoácidos/química , Sistema y+ de Transporte de Aminoácidos/ultraestrutura , Microscopia Crioeletrônica , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/metabolismo , Animais , Cadeia Pesada da Proteína-1 Reguladora de Fusão/química , Cadeia Pesada da Proteína-1 Reguladora de Fusão/genética , Cadeia Pesada da Proteína-1 Reguladora de Fusão/metabolismo , Cadeia Pesada da Proteína-1 Reguladora de Fusão/ultraestrutura , Células HEK293 , Humanos , Mutagênese , Domínios Proteicos , Estabilidade Proteica , Estrutura Secundária de Proteína , Células Sf9 , Spodoptera
8.
Nat Struct Mol Biol ; 26(6): 510-517, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160781

RESUMO

The L-type amino acid transporter 1 (LAT1 or SLC7A5) transports large neutral amino acids across the membrane and is crucial for brain drug delivery and tumor growth. LAT1 forms a disulfide-linked heterodimer with CD98 heavy chain (CD98hc, 4F2hc or SLC3A2), but the mechanism of assembly and amino acid transport are poorly understood. Here we report the cryo-EM structure of the human LAT1-CD98hc heterodimer at 3.3-Å resolution. LAT1 features a canonical Leu T-fold and exhibits an unusual loop structure on transmembrane helix 6, creating an extended cavity that might accommodate bulky amino acids and drugs. CD98hc engages with LAT1 through the extracellular, transmembrane and putative cholesterol-mediated interactions. We also show that two anti-CD98 antibodies recognize distinct, multiple epitopes on CD98hc but not its glycans, explaining their robust reactivities. These results reveal the principles of glycoprotein-solute carrier assembly and provide templates for improving preclinical drugs and antibodies targeting LAT1 or CD98hc.


Assuntos
Cadeia Pesada da Proteína-1 Reguladora de Fusão/química , Transportador 1 de Aminoácidos Neutros Grandes/química , Microscopia Crioeletrônica , Cadeia Pesada da Proteína-1 Reguladora de Fusão/metabolismo , Cadeia Pesada da Proteína-1 Reguladora de Fusão/ultraestrutura , Humanos , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/ultraestrutura , Modelos Moleculares , Conformação Proteica , Dobramento de Proteína , Multimerização Proteica
9.
Cell Rep ; 26(12): 3212-3220.e4, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893595

RESUMO

Metazoan cell death mechanisms are diverse and include numerous non-apoptotic programs. One program called entosis involves the invasion of live cells into their neighbors and is known to occur in cancers. Here, we identify a developmental function for entosis: to clear the male-specific linker cell in C. elegans. The linker cell leads migration to shape the gonad and is removed to facilitate fusion of the gonad to the cloaca. We find that the linker cell is cleared in a manner involving cell-cell adhesions and cell-autonomous control of uptake through linker cell actin. Linker cell entosis generates a lobe structure that is deposited at the site of gonad-to-cloaca fusion and is removed during mating. Inhibition of lobe scission inhibits linker cell death, demonstrating that the linker cell invades its host while alive. Our findings demonstrate a developmental function for entosis: to eliminate a migrating cell and facilitate gonad-to-cloaca fusion, which is required for fertility.


Assuntos
Caenorhabditis elegans/metabolismo , Comunicação Celular/fisiologia , Entose/fisiologia , Animais , Adesão Celular/fisiologia
10.
J Craniofac Surg ; 28(3): 768-770, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28468162

RESUMO

Mandibular contouring surgery was performed using computer-assisted simulation planning (CASP) and 3-dimensional printed surgical guide. The outcome of the surgery was evaluated by overlapping preoperative image. The patient underwent mandibular contouring surgery according to CASP for his residual facial asymmetry of the mandibular angle and mental area. The overall facial aesthetic of the patient was improved. In the overlapping image, the left mandibular border area was slightly overcorrected. However, the other portion was operated as planned. The overcorrection was due to the improper adaptation of the surgical guide adjacent to the mental foramen. In conclusion, usage of CASP and a surgical guide could reduce operation time and increase the accuracy of the operation. However, the design of the stent should be improved around the mental foramen to avoid nerve damage and improper adaptation.


Assuntos
Simulação por Computador , Desenho Assistido por Computador , Tomografia Computadorizada de Feixe Cônico/métodos , Assimetria Facial/cirurgia , Imageamento Tridimensional/métodos , Mandíbula/cirurgia , Cirurgia Assistida por Computador/métodos , Assimetria Facial/diagnóstico por imagem , Seguimentos , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Período Pós-Operatório , Fatores de Tempo , Interface Usuário-Computador , Adulto Jovem
11.
Dev Cell ; 38(5): 536-47, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27623384

RESUMO

The scavenging of extracellular macromolecules by engulfment can sustain cell growth in a nutrient-depleted environment. Engulfed macromolecules are contained within vacuoles that are targeted for lysosome fusion to initiate degradation and nutrient export. We have shown that vacuoles containing engulfed material undergo mTORC1-dependent fission that redistributes degraded cargo back into the endosomal network. Here we identify the lipid kinase PIKfyve as a regulator of an alternative pathway that distributes engulfed contents in support of intracellular macromolecular synthesis during macropinocytosis, entosis, and phagocytosis. We find that PIKfyve regulates vacuole size in part through its downstream effector, the cationic transporter TRPML1. Furthermore, PIKfyve promotes recovery of nutrients from vacuoles, suggesting a potential link between PIKfyve activity and lysosomal nutrient export. During nutrient depletion, PIKfyve activity protects Ras-mutant cells from starvation-induced cell death and supports their proliferation. These data identify PIKfyve as a critical regulator of vacuole maturation and nutrient recovery during engulfment.


Assuntos
Fosfatidilinositol 3-Quinases/genética , Canais de Potencial de Receptor Transitório/genética , Vacúolos/genética , Animais , Caenorhabditis elegans , Linhagem Celular Tumoral , Endossomos/genética , Endossomos/metabolismo , Humanos , Lisossomos/genética , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Fagocitose/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inanição , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Vacúolos/metabolismo
12.
Maxillofac Plast Reconstr Surg ; 37(1): 21, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26258114

RESUMO

Computer Assisted Simulation Surgery (CASS) is a reliable method that permits oral and maxillofacial surgeons to visualize the position of the maxilla and the mandible as observed in the patient. The purpose of this report was to introduce a newly developed strategy for proximal segment management according to Balanced Orthognathic Surgery (BOS) protocol which is a type of CASS, and to establish the clinical feasibility of the BOS protocol in the treatment of complex maxillo-facial deformities. The BOS protocol consists of the following 4 phases: 1) Planning and simulation phase, 2) Modeling phase, 3) Surgical phase, and 4) Evaluation phase. The surgical interventions in 80 consecutive patients were planned and executed by the BOS protocol. The BOS protocol ensures accuracy during surgery, thereby facilitating the completion of procedures without any complications. The BOS protocol may be a complete solution that enables an orthognatic surgeon to perform accurate surgery based on a surgical plan, making real outcomes as close to pre-planned outcomes as possible.

13.
Cell Res ; 25(6): 647-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25952669

RESUMO

Cell-in-cell structures resulting from live cell engulfment were identified more than 100 years ago, but their physiological significance has remained largely obscure. Now Ni et al. identify a new role for cell-in-cell structure formation, called "in-cell infection" that spreads Epstein-Barr virus from infected B cells to epithelial cells, an activity that may predispose to cancer.


Assuntos
Linfócitos B/virologia , Células Epiteliais/virologia , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/virologia , Neoplasias Nasofaríngeas/virologia , Humanos
14.
J Oral Maxillofac Surg ; 72(10): 1928-36, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25234528

RESUMO

PURPOSE: The objective of this study was to compare bone formation after installation of uncoated (UC), hydroxyapatite-coated (HA), collagen plus HA-coated (CH), and silk plus HA-coated (SH) implants. MATERIALS AND METHODS: Implants in the UC group had acid-etched surfaces. Surface coating was applied using the aerosol deposition method. Cellular responses on the coated surfaces were examined with scanning electron microscopy. Cellular responses to the surfaces were studied with the corresponding coated discs and MG63 cells. Subsequently, 3-(4, 5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphatase (ALP) assays were performed. Peri-implant bone formation was evaluated with the rabbit tibia model. Twenty-four implants from each group were installed. The animals were sacrificed 6 weeks after implant installation. Peri-implant bone formation and implant-to-bone contact were measured in histologic sections. Significance of differences across groups was evaluated using analysis of variance. RESULTS: Scanning electron microscopic images showed that the CH and SH groups exhibited cells that appeared more spread out than those in the other groups. The SH group exhibited the highest value in the MTT assay. The CH group exhibited the highest level of ALP activity. Comparisons of these modifications with the acid-etched surfaces showed that the CH and SH groups displayed significantly greater peri-implant bone formation (P < .001). CONCLUSION: The SH group displayed significantly greater new bone formation and bone-to-implant contact than did the other groups.


Assuntos
Materiais Revestidos Biocompatíveis/química , Colágeno Tipo I/química , Implantes Dentários , Durapatita/química , Osteogênese/fisiologia , Seda/química , Condicionamento Ácido do Dente/métodos , Aerossóis , Fosfatase Alcalina/análise , Animais , Adesão Celular/fisiologia , Técnicas de Cultura de Células , Linhagem Celular , Movimento Celular/fisiologia , Corantes , Materiais Dentários/química , Planejamento de Prótese Dentária , Microscopia Eletrônica de Varredura , Osseointegração/fisiologia , Osteoblastos/fisiologia , Coelhos , Propriedades de Superfície , Sais de Tetrazólio , Tiazóis , Titânio/química
15.
J Craniofac Surg ; 24(2): 632-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23524763

RESUMO

OBJECTIVE: The aim of this study was to compare new bone formation with titanium (Ti) surface and hydroxyapatite (HA)-coated titanium surface in mucosal perforation model. MATERIALS AND METHODS: HA coating to the Ti disc and implant were done by aerosol deposition technique. Alkaline phosphatase assay and cell migration assay were done in Ti and HA surface disc with MG63 cells. For the in vivo test, 5 New Zealand white rabbits were used. Two penetration defects were prepared in the nasal bone. Subsequently, 2 types of implants were installed into the defect (diameter: 3.0 mm, length: 6.0 mm). Approximately 5.0 mm of the fixture's surface penetrated into the nasal cavity. In the experimental group, HA-coated implants were used. The same design of implants without coating was used in the control group. The animals were sacrificed 8 weeks postoperatively. Subsequently, a histomorphometric analysis was done. RESULTS: Alkaline phosphatase activity was significantly higher in HA-coated surface than in titanium surface (P < 0.05). In addition, more cells were migrated into the HA-coated surface when compared to Ti surface. In the animal experiments, mean new bone formation was 30.68 ± 14.16% in the experimental group and 6.92 ± 5.12% in the control group (P = 0.001). Mean bone-to-implant contact was 31.71 ± 8.41% in the experimental group and 7.98 ± 5.58% in the control group (P < 0.001). Mean height of the bone regeneration was 3.70 ± 0.76 mm in the experimental group and 1.04 ± 0.67 mm in the control group. The difference between the 2 groups was statistically significant (P < 0.001). CONCLUSIONS: HA-coated implants exhibited more bone regeneration in the mucosal penetration model than the uncoated implants.


Assuntos
Durapatita/farmacologia , Osso Nasal/cirurgia , Osteogênese/efeitos dos fármacos , Próteses e Implantes , Titânio/farmacologia , Aerossóis , Fosfatase Alcalina/análise , Animais , Movimento Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Microscopia Eletrônica de Varredura , Osso Nasal/enzimologia , Coelhos
16.
Artigo em Inglês | MEDLINE | ID: mdl-22676926

RESUMO

OBJECTIVE: The objective of this study was to evaluate the application of platelet-rich fibrin (PRF) into a peri-implant defect in vivo. STUDY DESIGN: Eight New Zealand white rabbits were used for this study. Two peri-implants with defects sized 3.0 × 5.0 mm (width × length) were prepared after drilling to host the dental implant in the tibia. Subsequently, the 2 dental implants were installed (diameter, 3.0 mm and length, 8.0 mm). In the experimental group, PRF was applied into the bony defect. In the control group, the peri-implant defect was left unfilled. The animals were humanely killed 8 weeks after implantation and histomorphometric analysis was done. RESULTS: In the histomorphometric analysis, mean new bone formation was 29.30% ± 7.50% in the experimental group and 11.06% ± 8.94% in the control group (P = .020). Mean bone-to-implant contact was 39.43% ± 7.39% in the experimental group and 17.11% ± 8.12% in the control group (P = .006). CONCLUSIONS: In the animal model, peri-implant defect sized 3.0 × 5.0 mm (width × length) was successfully repaired by the application of PRF alone.


Assuntos
Perda do Osso Alveolar/cirurgia , Regeneração Óssea , Implantes Dentários , Fibrina/uso terapêutico , Perda do Osso Alveolar/tratamento farmacológico , Animais , Plaquetas/fisiologia , Substâncias de Crescimento/uso terapêutico , Modelos Animais , Coelhos , Tíbia/cirurgia
17.
Environ Toxicol Pharmacol ; 32(3): 382-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22004957

RESUMO

Helicobacter pylori (H. pylori) is associated with the development of gastric adenocarcinoma and lymphoma. However, the mechanisms through which H. pylori induces gastric mucosal lesions are not well defined. This study was conducted to evaluate the effect of the oncoprotein CagA on gastric cancer cells using whole-genome expression arrays. Human gastric epithelial (AGS) cells were incubated with CagA-positive H. pylori strains (147C (phosphorylated CagA) or 147A (dephosphorylated CagA)), and total protein and RNA were collected. The effects of phosphorylated and unphosphorylated CagA on AGS cells were then evaluated using Western blotting and microarray analysis. The expression levels of the genome profiles of AGS cells infected with 147A were compared with those of AGS cells infected with 147C. The expression profiles of the differentially expressed genes were grouped, and their expression patterns were validated via quantitative real-time PCR. Up- and down-regulated genes mainly included epithelial mesenchymal transition (EMT)-related genes. The results of the microarray analysis revealed that phosphorylated and unphosphorylated CagA may affect EMT in part through gene expression. This suggests that the intracellularly translocated CagA may be involved in EMT, resulting in differential expression of genes independent on the phosphorylation status of CagA.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Células Epiteliais/microbiologia , Regulação da Expressão Gênica , Helicobacter pylori/patogenicidade , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiologia , Western Blotting , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Genoma Humano , Infecções por Helicobacter/genética , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Humanos , Mesoderma , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Transporte Proteico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/patologia
18.
J Oral Maxillofac Surg ; 69(11): e354-63, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21821331

RESUMO

PURPOSE: Aerosol deposition is a newly developed technique, and it can deliver the drug from a hydroxyapatite (HA)-coated surface. 4-Hexylresorcinol (4-HR) is a well-known antiseptic. The influence of the 4-HR component of HA coatings on titanium surfaces was studied in vitro and in vivo. MATERIALS AND METHODS: X-ray diffraction and Fourier transform infrared techniques were used for the evaluation of the coating. The cellular response of the coating was evaluated by scanning electron microscopic study, MTT assay, alkaline phosphatase assay, and osteocalcin assay. In addition, the dental implant was coated with HA or HA + 4-HR. The implant was installed into the tibia of a rabbit after contamination by Aggregatibacter actinomycetemcomitans. The torque test and histologic analysis were then performed at 8 weeks after the operation. RESULTS: By use of an aerosol deposition technique, the combination of HA and 4-HR was successfully coated onto a titanium surface, which was confirmed by x-ray diffraction and Fourier transform infrared techniques. MG63 cells attached more rapidly to the HA + 4-HR coating than to the HA-only coating. The HA + 4-HR coating had significantly increased osteocalcin expression and alkaline phosphatase activity compared with the HA-only coating (P < .05). The dental implant coated with HA + 4-HR had a significantly higher removal torque value than that coated with HA alone at 8 weeks after surgery (P < .05). On histologic analysis, both the bone formation value and the bone-to-implant contact value were significantly higher in the HA + 4-HR group than in the HA-only group at 8 weeks after surgery (P < .05). CONCLUSIONS: Collectively, the HA + 4-HR-coated dental implant had clear advantages over the HA-coated dental implant. Therefore HA + 4-HR coatings can be considered for patients who need immediate implant installation after tooth extraction or who have poor-quality bone.


Assuntos
Anti-Infecciosos Locais/química , Materiais Revestidos Biocompatíveis/química , Ligas Dentárias/química , Implantes Dentários , Durapatita/química , Hexanos/química , Resorcinóis/química , Titânio/química , Aerossóis , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Fosfatase Alcalina/análise , Animais , Anti-Infecciosos Locais/farmacologia , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Corantes , Implantes Dentários/microbiologia , Contaminação de Equipamentos , Hexanos/farmacologia , Hexilresorcinol , Teste de Materiais , Microscopia Eletrônica de Varredura , Osseointegração/fisiologia , Osteoblastos/fisiologia , Osteocalcina/análise , Osteogênese/fisiologia , Porphyromonas gingivalis/efeitos dos fármacos , Prevotella intermedia/efeitos dos fármacos , Coelhos , Resorcinóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Sais de Tetrazólio , Tiazóis , Tíbia/cirurgia , Torque , Difração de Raios X
19.
Artigo em Inglês | MEDLINE | ID: mdl-21856192

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the bone regeneration ability of silk fibroin (SF) membrane. STUDY DESIGN: Fourier-transform infrared (FT-IR) and solubility test against distilled water were performed with 3 different types of SF membrane (SM1, SM2, and SM3). Subsequently, microscopic computerized tomography (µ-CT) and histomorphometric analyses were performed in rabbit calvarial defect model after SF membrane application at 4 and 8 weeks after surgery. RESULTS: FT-IR showed that the conformation of the SF membrane was a random coil structure and that SM1 was the least soluble. When SM1 was used in the animal model, the groups with SM1 had significantly higher new bone formation than the uncovered control in both the µ-CT and the histomorphometric analyses (P < .05). CONCLUSIONS: The SF membrane had more new bone formation compared with the uncovered control.


Assuntos
Regeneração Óssea/fisiologia , Fibroínas , Regeneração Tecidual Guiada/métodos , Membranas Artificiais , Seda , Animais , Bombyx , Densidade Óssea/fisiologia , Doenças Ósseas/patologia , Doenças Ósseas/cirurgia , Matriz Óssea/patologia , Amarelo de Eosina-(YS) , Estudos de Viabilidade , Fibroínas/química , Corantes Fluorescentes , Modelos Animais , Osteogênese/fisiologia , Osso Parietal/patologia , Osso Parietal/cirurgia , Conformação Proteica , Coelhos , Seda/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Água/química , Cicatrização/fisiologia , Microtomografia por Raio-X
20.
Oral Maxillofac Surg ; 15(3): 189-92, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21503623

RESUMO

BACKGROUND: Alveolar bone is usually resorbed after the loss of a tooth. As the buccal bony plate of the alveolar bone is thin compared to the palatal or the lingual bony plate, the bone resorption rate is higher on the buccal side. If a patient is partially edentulous, vertical bone resorption is restricted by the adjacent teeth. In such a case, the residual alveolar ridge becomes thin and narrow. As a result, a veneer graft is required. CASE REPORT: Two patients received a total of two implants with a modified technique. The modified technique is described in which the implant hole is made in both the mandibular ramus and the recipient site. Autogenous bone was taken from the mandibular ramus as a partial-thickness graft. The grafted bone was adapted to an installed dental implant and used as a veneer graft. There were no cases that showed the fixture exposure during the follow-up periods. Numbness was not reported after the operation in any of the cases. Additionally, osseointegration failures did not occur during the follow-up periods. CONCLUSION: Our technique has been shown high success rates and is reproducible for a veneer bone graft with concomitant implant installation.


Assuntos
Aumento do Rebordo Alveolar/métodos , Transplante Ósseo/métodos , Implantação Dentária Endóssea/métodos , Implantes Dentários , Seguimentos , Humanos , Arcada Parcialmente Edêntula/reabilitação , Arcada Parcialmente Edêntula/cirurgia , Masculino , Mandíbula/cirurgia , Pessoa de Meia-Idade , Osseointegração/fisiologia , Osteotomia/instrumentação , Osteotomia/métodos , Coleta de Tecidos e Órgãos/métodos , Resultado do Tratamento , Adulto Jovem
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