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1.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(3): 579-585, 2019 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-31209434

RESUMO

OBJECTIVE: To evaluate and to compare dimensional alterations of hard and soft tissues in molar extraction sites with irregular deficiency of bone plates due to advanced periodontitis receiving two different procedures, namely the flapped and flapless techniques with Bio-Gide membrane covering the Bio-Oss material for ridge preservation. METHODS: Twenty-three patients with 24 infected-molar extraction sites received ridge preservation procedure, the first consecutive 12 sites belonged to the flap group (a full thickness mucoperiosteal flap and primary soft tissue closure) and the following 12 sites belonged to the flapless group (minimal flap with a collagen sponge and a secondary soft tissue closure). Width of keratinized tissue was evaluated before tooth extraction and after 6-month healing. Parallel periapical radiographs were taken immediately and 6 months after extraction to evaluate vertical bone changes. The width of the ridge was measured in the center of the ridge at the time of tooth extraction and after 6 months at implant placement. RESULTS: After 6 months, width of keratinized tissue decreased (1.6±1.5) mm in the flap group (P=0.004) when compared with (0.3±1.6) mm in the flapless group (P>0.05). Both groups showed increases in ridge height from the central aspect, (5.53±4.20) mm for flap group and (7.70±4.35) mm for flapless group. These differences between the groups were not statistically significant (P=0.226). The ridge widths were (9.5±2.2) mm for flap group and (9.3±1.0) mm for flapless group at the time of implant insertion, and no statistical significance was observed between the flap and flapless groups. CONCLUSION: The study points out that both ridge preservation techniques were effective in increasing ridge height and minimizing ridge resorption after tooth extraction, and the ridge width allowed the placement of implants 6 months after ridge preservation. The flapless technique gave positive outcome in terms of the keratinized gingival width than that of the flap technique.


Assuntos
Periodontite , Alvéolo Dental , Processo Alveolar , Humanos , Dente Molar , Extração Dentária
2.
Br Dent J ; 222(1): 21-25, 2017 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-28084388

RESUMO

Objectives To evaluate long-term outcomes of modified crown lengthening procedures for crown-root fractured teeth, and to analyse factors that affect the periodontal health of the treated teeth.Methods The present study retrospectively analysed data from 22 patients (13 males and 9 females) who had presented with crown-root fractured teeth and received modified crown lengthening procedures combined with crown restoration for ≥13 months. In total, 26 crown-root fractured teeth were treated and examined for plaque index, probing depth, bleeding index, bleeding on probing, mobility and the crown margin location. The contralateral tooth and ipsilateral teeth mesial and distal to the treated tooth were used as controls. Data were assessed descriptively or analysed statistically with Mann-Whitney-U test at α=0.05.Results Recorded periodontal indices revealed stable periodontal status in 25 of 26 treated teeth with the mean values for aesthetic and functional VAS scores at 9.5. A negative correlation was observed between the subgingival crown margin location and the bleeding index.Conclusions The modified crown lengthening procedure is a feasible and minimally invasive therapeutic option for management of crown-root fractured cases.


Assuntos
Aumento da Coroa Clínica , Doenças Periodontais/etiologia , Coroa do Dente/lesões , Fraturas dos Dentes/cirurgia , Raiz Dentária/lesões , Adulto , Aumento da Coroa Clínica/métodos , Índice de Placa Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Estudos Retrospectivos , Coroa do Dente/cirurgia , Raiz Dentária/cirurgia , Adulto Jovem
3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(6): 1090-1094, 2016 12 18.
Artigo em Chinês | MEDLINE | ID: mdl-27987520

RESUMO

For ideal implant rehabilitation, an adequate bone volume, optical implant position, and stable and healthy soft tissue are required. The reduction of alveolar bone and changes in its morphology subsequent to tooth extraction will result in insufficient amount of bone and adversely affect the ability to optimally place dental implants in edentulous sites. Preservation of alveolar bone volume through ridge preservation has been demonstrated to reduce the vertical and horizontal contraction of the alveolar bone crest after tooth extraction and reduce the need for additional bone augmentation procedures during implant placement. In this case, a patient presented with a mandible molar of severe periodontal disease, the tooth was removed as atraumatically as possible and the graft material of Bio-Oss was loosely placed in the alveolar socket without condensation and covered with Bio-Gide to reconstruct the defects of the alveolar ridge. Six months later, there were sufficient height and width of the alveolar ridge for the dental implant, avoiding the need of additional bone augmentation and reducing the complexity and unpredictability of the implant surgery. Soft tissue defects, such as gingival and connective tissue, played crucial roles in long-term implant success. Peri-implant plastic surgery facilitated development of healthy peri-implant structure able to withstand occlusal forces and mucogingival stress. Six months after the implant surgery, the keratinized gingiva was absent in the buccal of the implant and the vestibular groove was a little shallow. The free gingival graft technique was used to solve the vestibulum oris groove supersulcus and the absence of keratinized gingiva around the implant. The deepening of vestibular groove and broadening of keratinized gingiva were conducive to the long-term health and stability of the tissue surrounding the implant. Implant installation and prosthetic restoration showed favorable outcome after six months.


Assuntos
Aumento do Rebordo Alveolar/métodos , Implantação Dentária Endo-Óssea/métodos , Gengiva/transplante , Vestibuloplastia/métodos , Processo Alveolar/patologia , Processo Alveolar/cirurgia , Autoenxertos/transplante , Colágeno/uso terapêutico , Implantes Dentários , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Minerais/uso terapêutico , Dente Molar/cirurgia , Osseointegração , Extração Dentária , Transplante Autólogo/métodos , Resultado do Tratamento
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 51(6): 362-7, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-27256531

RESUMO

OBJECTIVE: To construct three-dimensional finite element models with modified crown lengthening surgery and post-core restoration in management of various crown-root fracture types, to investigate the intensity and distribution of stressin models mentioned above, and to compare and analyze the indications of traditional and modified crown lengthening surgeries from the mechanic point of view. METHODS: Nine three-dimensional finite element models with modified crown lengthening surgery and post-core restoration were established and analyzed by micro-CT scanning technique, dental impression scanner, Mimics 10.0, Geomagic studio 9.0 and ANSYS 14.0 software. The von Mises stress of dentin, periodontal ligament, alveolar bone, post and core, as well as the periodontal ligament area and threshold limit value were calculated and compared with the findings of traditional crown lengthening models which had been published earlierby our research group. RESULTS: The von Mises stress intensity of modified crown lengthening models were: dentin>post>core>alveolar bone>periodontal ligament. The maximum von Mises stress of dentin(44.37-80.58 MPa)distributed in lingual central shoulder. The periodontal ligament area of the modified crown lengthening surgery was reduced by 6% to 28%, under the same crown-root fracture conditions, the periodontal ligament area of modified crown lengthening models was larger than that of the traditional crown lengthening models. In modified crown lengthening surgery models, the von Mises stress of periodontal ligament of B3L1m, B3L2m, B3L3m models exceeded their limit values, however, the von Mises stress of periodontal ligament of the B2L2c, B2L3c, B3L1c, B3L2c, B3L3c models exceeded their limit values in traditional crown lengthening surgery models. CONCLUSIONS: The modified crown lengthening surgery conserves more periodontal supporting tissues, which facilitates the long-term survival of teeth. The indication of modified crown lengthening surgery is wider than traditional method. The maxillary central incisors with labial fracture at gingival margin level and with palatal fracture at or below the alveolar crest level are not the indication of the crown lengthening surgery.


Assuntos
Aumento da Coroa Clínica/métodos , Análise de Elementos Finitos , Incisivo/lesões , Coroa do Dente/lesões , Fraturas dos Dentes/cirurgia , Raiz Dentária/lesões , Processo Alveolar , Coroas , Análise do Estresse Dentário , Dentina , Humanos , Ligamento Periodontal , Técnica para Retentor Intrarradicular , Níveis Máximos Permitidos , Microtomografia por Raio-X/métodos
5.
Genet Mol Res ; 14(3): 9412-22, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26345875

RESUMO

In this study, we examined phytoene synthetase (PSY), the first key limiting enzyme in the synthesis of carotenoids and catalyzing the formation of geranylgeranyl pyrophosphate in terpenoid biosynthesis. We used known amino acid sequences of the PSY gene in tomato plants to conduct a genome-wide search and identify putative candidates in 34 sequenced plants. A total of 101 homologous genes were identified. Phylogenetic analysis revealed that PSY evolved independently in algae as well as monocotyledonous and dicotyledonous plants. Our results showed that the amino acid structures exhibited 5 motifs (motifs 1 to 5) in algae and those in higher plants were highly conserved. The PSY gene structures showed that the number of intron in algae varied widely, while the number of introns in higher plants was 4 to 5. Identification of PSY genes in plants and the analysis of the gene structure may provide a theoretical basis for studying evolutionary relationships in future analyses.


Assuntos
Geranil-Geranildifosfato Geranil-Geraniltransferase/genética , Proteínas de Plantas/genética , Plantas/genética , Motivos de Aminoácidos , Biologia Computacional , Bases de Dados Genéticas , Genoma de Planta , Geranil-Geranildifosfato Geranil-Geraniltransferase/química , Geranil-Geranildifosfato Geranil-Geraniltransferase/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas/classificação , Plantas/metabolismo
6.
Genet Mol Res ; 14(3): 7947-56, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26214476

RESUMO

Tomato yellow leaf curl virus is one of the main diseases affecting tomato production worldwide. Previous studies have shown that Ty-2 is an important resistance gene located between molecular markers C2_At2g28250 (82.3 cM) and T0302 (89.0 cM), and exhibits strong resistance to tomato yellow leaf curl virus in Asia. In this study, Ty-2 candidate genes were subjected to bioinformatic analysis for the sequenced tomato genome. We identified 69 genes between molecular markers C2_At2g28250 and T0302, 22 of which were disease-related resistant genes, including nucleotide binding site-leucine-rich repeat disease resistance genes, protease genes (protein kinase, kinase receptor, and protein isomerase), cytochromes, and transcription factors. Expressed sequence tag analysis revealed that 77.3% (17/22) of candidate disease-resistance genes were expressed, involving 143 expressed sequence tags. Based on full-length cDNA sequence analysis, 7 candidate genes were found, 4 of which were involved in tomato responses to pathogens. Microarray expression analysis also showed that most candidate genes were involved in the tomato responses to multiple pathogens, including fungi, viruses, and bacteria. RNA-seq expression analysis revealed that all candidate genes participated in tomato growth and development.


Assuntos
Mapeamento Cromossômico , Simulação por Computador , Resistência à Doença/genética , Genes de Plantas , Lycopersicon esculentum/genética , Lycopersicon esculentum/virologia , Doenças das Plantas/genética , Begomovirus/fisiologia , DNA Complementar/genética , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estudos de Associação Genética , Análise de Sequência com Séries de Oligonucleotídeos , Doenças das Plantas/virologia , Análise de Sequência de RNA
7.
Crit Rev Biotechnol ; 35(2): 269-80, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24083451

RESUMO

Cyanobacteria have developed various response mechanisms in long evolution to sense and adapt to external or internal changes under abiotic stresses. The signal transduction system of a model cyanobacterium Synechocystis sp. PCC 6803 includes mainly two-component signal transduction systems of eukaryotic-type serine/threonine kinases (STKs), on which most have been investigated at present. These two-component systems play a major role in regulating cell activities in cyanobacteria. More and more co-regulation and crosstalk regulations among signal transduction systems had been discovered due to increasing experimental data, and they are of great importance in corresponding to abiotic stresses. However, mechanisms of their functions remain unknown. Nevertheless, the two signal transduction systems function as an integral network for adaption in different abiotic stresses. This review summarizes available knowledge on the signal transduction network in Synechocystis sp. PCC 6803 and biotechnological implications under various stresses, with focuses on the co-regulation and crosstalk regulations among various stress-responding signal transduction systems.


Assuntos
Biotecnologia/métodos , Transdução de Sinais , Estresse Fisiológico , Synechocystis
8.
Pharmazie ; 61(8): 681-4, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16964710

RESUMO

A solid dispersion containing cyclosporine A (CyA) and polyoxyethylene (40) stearate (PS) was prepared by the solvent-melt method and characterized by powder X-ray diffraction (PXRD), hot-stage microscopy (HSM), scanning electron microscopy (SEM) and dissolution studies. The crystalline peaks of CyA disappeared in the PXRD spectra of solid dispersions but were seen in those of physical mixtures, demonstrating the amorphous state of the drug in solid dispersions. The solubility of CyA in aqueous solutions of PS was increased linearly with increasing amount of PS in water. Dissolution of the drug from solid dispersions and physical mixtures was dramatically enhanced compared to the drug powder alone in water at 37 degrees C.


Assuntos
Ciclosporina/química , Imunossupressores/química , Algoritmos , Fenômenos Químicos , Físico-Química , Cristalografia por Raios X , Diglicerídeos/química , Excipientes , Microscopia Eletrônica de Varredura , Polietilenoglicóis/química , Solubilidade , Termodinâmica
9.
J Interferon Cytokine Res ; 20(4): 403-9, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10805375

RESUMO

Recently, it has become clear that interferon-gamma (IFN-gamma) plays a role in the central nervous system (CNS) as well as in the immune system. However, the reason for the alteration in IFN-gamma production in the brain with aging remains unknown. In this study, we investigated the expression of IFN-gamma in the brain in terms of both mRNA and protein and compared the expression in young adult brain with that in aged mice. The cerebrum and cerebellum were collected from young adult (8-10 weeks old) and aged (24-26 months old) BALB/c mice, and the expressions of IFN-gamma and IFN-gamma receptor-1 (IFNGR-1) mRNA were examined by RT-PCR. Expression of IFN-gamma mRNA was detected in the brains from aged mice but not in those from young adult mice. However, IFNGR-1 mRNA was expressed in the brains from both young adult and aged mice. Moreover, IFN-gamma levels in the cerebrum and cerebellum from aged mice were detectable by ELISA, but IFN-gamma was undetectable in these tissues from young adult mice. To identify the cellular source of IFN-gamma in the brain of aged mice, immunostaining using antimouse IFN-gamma monoclonal antibody (mAb) was done. Immunoreactivity of IFN-gamma appeared to be located in cerebrovascular endothelial cells, including the choroid plexus of the cerebellum from aged mice. Expression of IFN-gamma and IFNGR-1 was also identified in isolated microvessels from brains. These results suggest that IFN-gamma plays a role in age-associated changes.


Assuntos
Envelhecimento/imunologia , Química Encefálica/imunologia , Encéfalo/irrigação sanguínea , Encéfalo/imunologia , Endotélio Vascular/metabolismo , Interferon gama/biossíntese , Animais , Encéfalo/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Feminino , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Interferon/biossíntese
10.
Infect Immun ; 68(2): 664-71, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10639431

RESUMO

Cytokines have been proposed to play an important role in Helicobacter pylori-associated gastroduodenal diseases, but the exact mechanism of the cytokine induction remains unclear. H. pylori urease, a major component of the soluble proteins extracted from bacterial cells, is considered to be one of the virulence factors for the inflammation in the gastric mucosa that is produced in H. pylori infection. However, the response of human gastric epithelial cells to the stimulation of urease has not been investigated. In the present study, we used human gastric epithelial cells in a primary culture system and examined whether H. pylori urease stimulates the gastric epithelial cells to induce proinflammatory cytokines by reverse transcription-PCR and enzyme-linked immunosorbent assay. First, by using peripheral blood mononuclear cells (PBMC) and a gastric cancer cell line (MKN-45 cells), we confirmed the ability of purified H. pylori urease to induce the production of proinflammatory cytokines. Furthermore, we demonstrated that the human gastric epithelial cells produced interleukin-6 (IL-6) and tumor necrosis factor alpha, but not IL-8, following stimulation with purified urease. The patterns of cytokine induction differed among human PBMC, MKN-45 cells, and human gastric epithelial cells. These results suggest that the human gastric epithelial cells contribute to the induction of proinflammatory cytokines by the stimulation of H. pylori urease, indicating that the epithelial cells were involved in the mucosal inflammation that accompanied H. pylori infection.


Assuntos
Citocinas/biossíntese , Mucosa Gástrica/microbiologia , Helicobacter pylori/enzimologia , Urease/farmacologia , Adulto , Linhagem Celular , Citocinas/genética , Mucosa Gástrica/imunologia , Humanos , Interleucina-6/biossíntese , Interleucina-8/biossíntese , RNA Mensageiro/análise
11.
Cell Regul ; 1(9): 661-74, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2150334

RESUMO

We present results from studies of human cell culture models to support the premise that the extracellular transport of lysosomal acid lipase has a function in lipoprotein cholesteryl ester metabolism in vascular tissue. Vascular endothelial cells secreted a higher fraction of cellular acid lipase than did smooth muscle cells and fibroblasts. Acid lipase and lysosomal beta-hexosaminidase were secreted at approximately the same rate from the apical and basolateral surface of an endothelial cell monolayer. Stimulation of secretion with NH4Cl did not affect the polarity. We tested for the ability of secreted endothelial lipase to interact with connective tissue cells and influence lipoprotein cholesterol metabolism in a coculture system in which endothelial cells on a micropore filter were suspended above a monolayer of acid lipase-deficient (Wolman disease) fibroblasts. After 5-7 d, acid lipase activity in the fibroblasts reached 10%-20% of the level in normal cells; cholesteryl esters that had accumulated from growth in serum were cleared. Addition of mannose 6-phosphate to the coculture medium blocked acid lipase uptake and cholesterol clearance, indicating that lipase released from endothelial cells was packaged into fibroblast lysosomes by a phosphomannosyl receptor-mediated pathway. Supplementation of the coculture medium with serum was not required for lipase uptake and cholesteryl ester hydrolysis by the fibroblasts, but was necessary for cholesterol clearance. Results from our coculture model suggest that acid lipase may be transported from intact endothelium to cells in the lumen or the wall of a blood vessel. We postulate that delivery of acid hydrolases and lipoproteins to a common endocytic compartment may occur and have an impact on cellular lipoprotein processing.


Assuntos
Ésteres do Colesterol/metabolismo , Endotélio Vascular/metabolismo , Fibroblastos/metabolismo , Lipase/metabolismo , Lisossomos/enzimologia , Transporte Biológico , Sangue , Comunicação Celular , Células Cultivadas , Humanos , Cinética , L-Lactato Desidrogenase/metabolismo , Lipoproteínas/metabolismo , Manosefosfatos/metabolismo , Fatores de Tempo , Doença de Wolman/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo
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