RESUMO
AIM: To investigate the effects of recombinant human vascular endothelial growth factor (rhVEGF) on odontoblastic differentiation, in vitro angiogenesis, and expression and activity of lysyl oxidase (LOX) in human dental pulp cells (HDPCs), compared with rhFGF-2. To identify the underlying molecular mechanisms, the study focused on whether LOX was responsible for the actions of rhVEGF. METHODOLOGY: Recombinant human vascular endothelial growth factor (rhVEGF) was constructed using the pBAD-HisA plasmid in Escherichia coli. HDPCs were treated with 1-50 µg mL-1 rhVEGF for 14 days. Alkaline phosphatase (ALP) activity was measured, and the formation of calcified nodules was assessed using alizarin red staining after the induction of odontogenic differentiation of HDPCs. The expression level of the odontogenic differentiation markers was detected by reverse transcription polymerase chain reaction. Signal pathways were assessed by Western blot and immunocytochemistry. The data were analysed by anova with Bonferroni's test (α = 0.05). RESULTS: Recombinant human vascular endothelial growth factor significantly increased cell growth (P < 0.05), ALP activity (P < 0.05) and mineralization nodule formation and upregulated the mRNA expression levels of the osteogenic/odontogenic markers that were lower with rhFGF-2. rhVEGF significantly increased amine oxidase activity (P < 0.05) and upregulated LOX and LOXL mRNA expression in HDPCs. Additionally, rhVEGF dose-dependently upregulated angiogenic gene mRNAs and capillary tube formation to a greater degree than rhFGF-2. Inhibition of LOX using ß-aminopropionitrile (BAPN) and LOX or LOXL gene silencing by RNA interference attenuated rhVEGF-induced growth, ALP activity, mineralization, the expression of marker mRNAs and in vitro angiogenesis. Furthermore, treatment with rhVEGF resulted in phosphorylation of Akt, ERK, JNK and p38, and activation of NF-κB, which was inhibited by LOX or LOXL silencing and BAPN. CONCLUSION: Recombinant human vascular endothelial growth factor promoted cell growth, odontogenic potential and in vitro angiogenesis via modulation of LOX expression. These results support the concept that rhVEGF may offer therapeutic benefits in regenerative endodontics.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Polpa Dentária/citologia , Neovascularização Fisiológica/efeitos dos fármacos , Proteína-Lisina 6-Oxidase/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Western Blotting , Linhagem Celular , Polpa Dentária/efeitos dos fármacos , Polpa Dentária/crescimento & desenvolvimento , Humanos , Proteína-Lisina 6-Oxidase/antagonistas & inibidores , Proteínas Recombinantes , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
AIM: To assess whether SIRT1 and VEGF are responsible for tumour necrosis factor-α (TNF-α) and lipopolysaccharide (LPS)-induced angiogenesis and to examine the molecular mechanism(s) of action in human dental pulp cells (HDPCs). METHODOLOGY: Immortalized HDPCs obtained from Prof. Takashi Takata (Hiroshima University, Japan) were treated with LPS (1 µg mL(-1) ) and TNF-α (10 ng mL(-1) ) for 24 h. mRNA and protein levels were examined by RT-PCR and Western blotting, respectively. Migration and tube formation were examined in human umbilical vein endothelial cells (HUVECs). The data were analysed by one-way anova. Statistical analysis was performed at α = 0.05. RESULTS: LPS and TNF-α upregulated VEGF and SIRT1 mRNA and protein levels. Inhibition of SIRT1 activity by sirtinol and SIRT1 siRNA or inhibition of the VEGF receptor by CBO-P11 significantly attenuated LPS + TNF-α-stimulated MMPs production in HDPCs, as well as migration and tube formation in HUVECs (P < 0.05). Furthermore, sirtinol, SIRT1 siRNA and CBO-P11 attenuated phosphorylation of Akt, extracellular signal-regulated kinase (ERK), p38 and c-Jun N-terminal kinase (JNK) and the nuclear translocation of NF-κB p65. Pre-treatment with inhibitors of p38, ERK, JNK, PI3K and NF-κB decreased LPS + TNF-α-induced VEGF and SIRT1 expression, MMPs activity in HDPCs and angiogenesis (P < 0.05) in HUVECs. CONCLUSIONS: TNF-α and LPS led to upregulation of VEGF and SIRT1, and subsequent upregulation of MMP-2 and MMP-9 production, and promote angiogenesis via pathways involving PI3K, p38, ERK, JNK and NF-κB. The results suggest that inhibition of SIRT1 and VEGF might attenuate pro-inflammatory mediator-induced pulpal disease.
Assuntos
Polpa Dentária/metabolismo , Lipopolissacarídeos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Sirtuína 1/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Western Blotting , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Polpa Dentária/citologia , Fatores de Crescimento Endotelial/farmacologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Naftóis/farmacologia , Peptídeos Cíclicos/farmacologia , Fosforilação , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Regulação para CimaRESUMO
The immobilization process of glucose oxidase(GOx) in the poly(1,3-diaminobenzene) (poly(1,3-DAB)) network was closely investigated in situ using an electrochemical quartz crystal microbalance(EQCM). GOx captured in approximately 50 nm thick poly-1,3-DAB layer causes a 514 Hz frequency increase, corresponding to 541 ng, and distributes mostly in the outer part of the polymer film. The presence of poly-L-lysine and glutaraldehyde during electropolymerization of poly(1,3-DAB) improves sensitivity by raising the amount of GOx immobilized. Adding a protective membrane on to the enzyme layer from poly(tetrafluoroethylene) (PTFE) dispersed in aqueous media lets the entire fabrication procedure finish perfectly without nonaqueous solvent. The finalized needle-type glucose sensors show competent functions in sensitivity, stability, biocompatibility, lifetime, interference and reproducibility.
Assuntos
Técnicas Biossensoriais/métodos , Glucose/análise , Monitorização Fisiológica/métodos , Técnicas Biossensoriais/instrumentação , Eletroquímica , Enzimas Imobilizadas , Glucose Oxidase , Humanos , Técnicas In Vitro , Miniaturização , Monitorização Fisiológica/instrumentação , Sistemas On-Line/instrumentação , Fenilenodiaminas , Polímeros , Politetrafluoretileno , Quartzo , Reprodutibilidade dos TestesRESUMO
This study evaluated the effects of various porcelain surface treatments on the microleakage of the porcelain-composite interface. The experimental model isolated and evaluated only the porcelain-composite interface without the presence of a bond to tooth structure. Four types of porcelain were fired into circular porcelain tabs 1.0 mm thick by 8.5 mm in diameter. The groups of porcelain were divided into subgroups for treatment with hydrofluoric acid-etching and silane. A jig standardizing composite thickness to 0.2 mm was used to photopolymerize composite to porcelain. The margins were finished and polished with burs and disks. Samples were stored in 37 degrees C water thermocycled 1000X, placed in AgNO3 solution, embedded in epoxy, and cross-sectioned every 90 degrees for measurement of stain penetration at the composite-porcelain interface. Occasional crazing of porcelain from composite polymerization shrinkage was observed. Porcelain surface treatment significantly increased the specimens' ability to withstand water storage and thermal-cycling procedures. Porcelain surface treatment with silane alone did not reduce microleakage, but, in combination with etching, reduced microleakage significantly.
Assuntos
Colagem Dentária , Infiltração Dentária , Porcelana Dentária , Condicionamento Ácido do Dente , Análise de Variância , Distribuição de Qui-Quadrado , Ácido Fluorídrico , Silanos , Coloração e Rotulagem , Propriedades de Superfície , Análise de Sobrevida , Resistência à TraçãoRESUMO
In-Ceram is a sintered, high-alumina-content, glass-infiltrated ceramic core material reported to have sufficient strength for all-ceramic fixed partial dentures. While Vita/Vident recommends that In-Ceram should be used only for anterior FPDs, the purpose of this study was to push the sintered alumina material to its limits by testing posterior FPDs with premolar and molar pontics. This prospective clinical trial tested the longevity of 61 three-unit In-Ceram alumina FPDs. The failed specimens were analyzed to determine factors contributing to failure. The abutment teeth were prepared for full crown retainers with shoulder margins and 1.3 mm of axial reduction. All FPDs were cemented with an encapsulated glass ionomer. None of the patients reported postcementation sensitivity. During the three-year period, seven FPDs fractured through the connector area. By location of the pontic, failure rates were 0 percent for anteriors, 11 percent for premolars and 24 percent for molars. Based on the results of this clinical study at the three-year point, In-Ceram alumina can be reliably utilized for anterior FPDs as indicated by a 100 percent success rate. The findings do not support the use of In-Ceram alumina for posterior FPDs as was advised by the porcelain manufacturer. Glass ionomer cement can be predictably used to cement In-Ceram FPDs with few clinical side effects. Because of a technological malfunction, this article could not be presented with the others on ceramic restorations that appeared in the February issue.
Assuntos
Óxido de Alumínio/uso terapêutico , Porcelana Dentária/uso terapêutico , Planejamento de Dentadura , Prótese Parcial Fixa , Falha de Restauração Dentária , Estética Dentária , Cimentos de Ionômeros de Vidro , Humanos , Preparo do Dente , Resultado do TratamentoRESUMO
Mucoceles are commonly occurring lesions of the oral mucous membrane and the most common lesion involving minor salivary tissue. The incidence of mucoceles is understandable since accessary salivary gland tissue is widely distributed throughout the oral mucous membrane and trauma to the mucosa, which causes their formation, occurs frequently. But only a few studies have been reported that describe its detailed features. This is a retrospective study on the salivary mucoceles in the oral mucous membrane and based on clinical chart, biopsy request and photomicroscopic finding of 112 patients treated by Dept. of Oral Surgery in Seoul National University Hospital, during the period of last 10 years. The results were as following. 1. The age range of the 112 patients was 2 to 60 years, with a peak incidence in the second decade and a gradual decline thereafter. Of the 112 patients, 49 (44%) were males and 63 (56%) were females, the male-to-female ratio being 1:1.29. 2. The majority of these lesions were located on the lower lip but occurred with lesser frequently on the buccal mucosa, floor of the mouth, tongue, retromolar region, upper lip. 3. Of the 112 patients, 107 (95%) were treated by excision and only 5 were treated by marsupialization. 18 of 112 cases had recurrence and the recurrence rate in this study was 16%. 4. Only 3 of the 112 cases revealed an epithelial lining. This incidence indicates that the mucus-extravasation by the damage of excretory duct rather than the ductal dilatation by mucus-retention may play a critical role in the production of these lesions. 5. In 81 cases (72.3%) minor salivary gland were included in the excision biopsy, specimen. Changes observed in the glandular tissue were atrophy and infiltration of chronic inflammatory cell, but the secretory function of gland was thought to be normal in most cases because the changes were mild.
Assuntos
Doenças da Boca/patologia , Mucocele/patologia , Doenças das Glândulas Salivares/patologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Boca/cirurgia , Mucocele/cirurgia , Estudos Retrospectivos , Doenças das Glândulas Salivares/cirurgiaRESUMO
This study was conducted to determine the effectiveness of a silicone disclosing medium, G-C Fit-Checker, as an aid in the improvement of marginal integrity. Standardized preparations were made on 42 freshly extracted premolars. Base metal alloy castings were finished externally and initially adjusted internally. The castings were placed on their respective teeth and the marginal opening was determined. They were then adjusted twice using the silicone material and remeasured. The preadjustment mean marginal opening was 92 microns and the postadjustment measurement 55 microns, yielding a mean reduction of 37 microns (SEM 3 microns) or 39%.
Assuntos
Coroas , Materiais para Moldagem Odontológica , Técnica de Moldagem Odontológica , Silicones , Dente Pré-Molar , Infiltração Dentária/diagnóstico , Humanos , Indicadores e Reagentes , Teste de MateriaisRESUMO
Platelet concentrates (PCs), stored for 5 days in PL 2209, a new polyvinyl chloride (PVC) storage container plasticised with butyryl trihexyl citrate, were compared with those stored in PL 1240, a PVC platelet container plasticised with triethylhexyl trimellitate. In part 1 of the study, pooled platelet-rich plasma (PRP) was aliquoted into each type of pack and pH, pCO2, pO2, hypotonic shock response, aggregation responses, lactate, glucose and ATP concentrations, and lactate dehydrogenase and beta-thromboglobulin release were compared at days 1, 3 and 5. In part 2, 12 volunteers gave a unit of blood on two separate occasions and PCs produced by the PRP method were stored in PL 2209 or PL 1240 for 5 days before autologous reinfusion of a 111In-labelled sample. In vitro results demonstrated that PL 2209 was more gas permeable than PL 1240. In part 2 of the study, at day 5, pCO2 was 3.13 +/- 0.62 versus 5.14 +/- 0.69 (p < 0.001), whilst pO2 was not significantly different for PL 2209 versus PL 1240, respectively. pH was better maintained in PL 2209 than in PL 1240 (7.38 +/- 0.13 vs. 7.24 +/- 0.10, respectively, p < 0.01) after storage for 5 days. These results were confirmed by those from part 1. In vivo data were similar for PC stored in the two plastics with a multiple-hit recovery of 40.9 +/- 12.1% for PL 2209 and 37.4 +/- 11.3% for PL 1240, and a multiple-hit survival of 4.89 +/- 1.20 days and 5.28 +/- 2.06 days for PL 2209 and PL 1240, respectively. gamma-Camera imaging of volunteers showed similar biodistribution of radiolabelled platelets stored in each container. These results demonstrate that PL 2209 is a suitable container for storage of PCs for 5 days.
Assuntos
Benzoatos/química , Plaquetas/química , Preservação de Sangue/métodos , Butiratos/química , Plastificantes/química , Cloreto de Polivinila/química , Doadores de Sangue , Plaquetas/diagnóstico por imagem , Sobrevivência Celular/efeitos dos fármacos , Humanos , Técnicas In Vitro , Contagem de Plaquetas , CintilografiaRESUMO
This study measured the in vitro microleakage of conventional and new FPD luting agents. Standardized preparations were made on 42 freshly extracted premolars. Facial and lingual chamfer margins were placed in enamel, mesial and distal in dentin and cementum, and castings were made in Rexillium III alloy and were then cemented with a standardized technique. Six groups of seven samples were tested, (1) polycarboxylate, (2) zinc phosphate, (3) glass ionomer, (4) Den-Mat Thin Film cement, (5) Panavia Ex, and (6) Den-Mat Thin Film cement with Tenure. The ranking of groups for stain ingress was from the greatest (1) to the least (6). A one-way analysis of variance and Tukey-Student range analysis revealed significantly similar groups, p less than 0.05:(1,2,3,4) (5,6).
Assuntos
Adesivos/química , Coroas , Cimentos Dentários/química , Infiltração Dentária , Prótese Parcial Fixa , Cimentos de Resina , Cimentação , Corantes , Resinas Compostas/química , Colagem Dentária , Esmalte Dentário/anatomia & histologia , Dentina/anatomia & histologia , Planejamento de Dentadura , Humanos , Óxido de Magnésio/química , Teste de Materiais , Fosfatos/química , Cimento de Policarboxilato/química , Propriedades de Superfície , Óxido de Zinco/química , Cimento de Fosfato de Zinco/químicaRESUMO
PURPOSE: To evaluate the usefulness of flexible covered stents for treatment of acute colorectal obstruction secondary to malignant colorectal carcinoma. MATERIALS AND METHODS: Twenty patients with acute colorectal obstruction secondary to malignant colorectal carcinoma were treated by means of intubation of a flexible stent with fluoroscopic guidance with occasional endoscopic assistance. Two types of stents were placed (type 1, completely covered, type 2, two-thirds of proximal part uncovered). Of 15 patients with primary colorectal carcinoma, 12 underwent placement of a stent for presurgical decompression of colorectal obstruction; three, for palliative decompression. In three patients with rectosigmoid seeding from advanced gastric carcinoma and two patients with recurrent colonic carcinoma, stents were placed for palliative decompression. RESULTS: Stent placement was successful in 18 (90%) of 20 patients. Symptoms of obstruction resolved within 24 hours in 15 (75%) patients. Eight patients underwent elective single-stage surgery without complications 5-7 days after stent placement. Two patients underwent tumor resection and colostomy. In eight patients, stents provided palliative decompression of the colon. Type 1 stents migrated in four (50%) of eight patients; type 2 stents were used thereafter. CONCLUSION: Flexible stents effectively relieved acute colonic obstruction secondary to malignant rectosigmoid neoplasm. Stent placement allowed patients to undergo single-stage surgery in most cases and provided palliative decompression in cases of inoperable or disseminated disease.