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1.
Photochem Photobiol Sci ; 18(10): 2442-2448, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31384873

RESUMO

In recent years, several drugs have become relatively easy to obtain with the rapid development of the economy and improvement in people's living standards. However, pathogenic bacteria have evolved strains that are resistant to certain drugs, such as antibiotics. Peptides are generally considered to be safe, have high tolerance to drugs, and are easy to manufacture. However, peptides are easily decomposed in complex biological environments. To solve this problem, many studies have modified peptides on the surface of nanomaterials to increase their functionality, biocompatibility, and stability. Meanwhile, nanomaterials have exhibited good absorption of near-infrared (NIR) light. When the NIR laser is focused on nanomaterials, photons are absorbed and the energy of the photons is converted into heat. Low-toxicity NRC03 peptide-conjugated dopamine/nano-reduced-graphene oxide (NRC03-DA/nRGO) nanomaterials are synthesized in this study for antibacterial testing using photothermal technology. The strains used in this study were Gram-positive Staphylococcus aureus (S. aureus). Our results indicated that the synthesized NRC03-DA/nRGO exhibits good absorption of NIR light and high photothermal conversion efficiency. Moreover, the synthesized NRC03-DA/nRGO inhibits the growth and survival of S. aureus. When the NRC03 peptide is modified on the surface of DA/nRGO, its biological stability is improved and the photothermal effect generated by NIR light produces additive effects, thereby indicating potential antibacterial applications.


Assuntos
Antibacterianos/farmacologia , Dopamina/química , Grafite/química , Nanoestruturas/química , Peptídeos/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Raios Infravermelhos
2.
Ann Oncol ; 29(6): 1402-1408, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29659672

RESUMO

Background: Arginine depletion is a putative target in hepatocellular carcinoma (HCC). HCC often lacks argininosuccinate synthetase, a citrulline to arginine-repleting enzyme. ADI-PEG 20 is a cloned arginine degrading enzyme-arginine deiminase-conjugated with polyethylene glycol. The goal of this study was to evaluate this agent as a potential novel therapeutic for HCC after first line systemic therapy. Methods and patients: Patients with histologically proven advanced HCC and Child-Pugh up to B7 with prior systemic therapy, were randomized 2 : 1 to ADI-PEG 20 18 mg/m2 versus placebo intramuscular injection weekly. The primary end point was overall survival (OS), with 93% power to detect a 4-5.6 months increase in median OS (one-sided α = 0.025). Secondary end points included progression-free survival, safety, and arginine correlatives. Results: A total of 635 patients were enrolled: median age 61, 82% male, 60% Asian, 52% hepatitis B, 26% hepatitis C, 76% stage IV, 91% Child-Pugh A, 70% progressed on sorafenib and 16% were intolerant. Median OS was 7.8 months for ADI-PEG 20 versus 7.4 for placebo (P = 0.88, HR = 1.02) and median progression-free survival 2.6 months versus 2.6 (P = 0.07, HR = 1.17). Grade 3 fatigue and decreased appetite occurred in <5% of patients. Two patients on ADI-PEG 20 had ≥grade 3 anaphylactic reaction. Death rate within 30 days of end of treatment was 15.2% on ADI-PEG 20 versus 10.4% on placebo, none related to therapy. Post hoc analyses of arginine assessment at 4, 8, 12 and 16 weeks, demonstrated a trend of improved OS for those with more prolonged arginine depletion. Conclusion: ADI-PEG 20 monotherapy did not demonstrate an OS benefit in second line setting for HCC. It was well tolerated. Strategies to enhance prolonged arginine depletion and synergize the effect of ADI-PEG 20 are underway. Clinical Trial number: www.clinicaltrials.gov (NCT 01287585).


Assuntos
Carcinoma Hepatocelular/terapia , Hidrolases/uso terapêutico , Neoplasias Hepáticas/terapia , Cuidados Paliativos , Polietilenoglicóis/uso terapêutico , Carcinoma Hepatocelular/patologia , Terapia Combinada , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
3.
Osteoarthritis Cartilage ; 21(10): 1613-22, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23927932

RESUMO

OBJECTIVE: Repairing articular cartilage is clinically challenging. We investigated a simple, effective and clinically feasible cell-based therapeutic approach using a poly(lactide-co-glycolide) (PLGA) scaffold seeded with autologous endothelial progenitor cells (EPC) to repair a full-thickness osteochondral defect in rabbits using a one-step surgery. METHODS: EPC obtained by purifying a small amount of peripheral blood from rabbits were seeded into a highly porous, biocompatible PLGA scaffold, namely, EPC-PLGA, and implanted into the osteochondral defect in the medial femoral condyle. Twenty two rabbits were randomized into one of three groups: the empty defect group (ED), the PLGA-only group or the EPC-PLGA group. The defect sites were evaluated 4 and 12 weeks after implantation. RESULTS: At the end of testing, only the EPC-PLGA group showed the development of new cartilage tissue with a smooth, transparent and integrated articular surface. Moreover, histological analysis showed obvious differences in cartilage regeneration. At week 4, the EPC-PLGA group showed considerably higher TGF-ß2 and TGF-ß3 expression, a greater amount of synthesized glycosaminoglycan (GAG) content, and a higher degree of osteochondral angiogenesis in repaired tissues. At week 12, the EPC-PLGA group showed enhanced hyaline cartilage regeneration with a normal columnar chondrocyte arrangement, higher SOX9 expression, and greater GAG and collagen type II (COLII) content. Moreover, the EPC-PLGA group showed organized osteochondral integration, the formation of vessel-rich tubercular bone and significantly higher bone volume per tissue volume and trabecular thickness (Tb.Th). CONCLUSION: The present EPC-PLGA cell delivery system generates a suitable in situ microenvironment for osteochondral regeneration without the supplement of exogenous growth factors.


Assuntos
Cartilagem Articular/fisiologia , Células Endoteliais/transplante , Regeneração , Transplante de Células-Tronco/métodos , Alicerces Teciduais , Animais , Materiais Biocompatíveis , Regeneração Óssea/fisiologia , Cartilagem Articular/lesões , Cartilagem Articular/patologia , Condrócitos/fisiologia , Fêmur/irrigação sanguínea , Fêmur/patologia , Fêmur/fisiologia , Ácido Láctico , Masculino , Neovascularização Fisiológica/fisiologia , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Engenharia Tecidual/métodos , Microtomografia por Raio-X/métodos
4.
J Periodontal Res ; 48(1): 66-73, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22834967

RESUMO

BACKGROUND AND OBJECTIVE: Short-chain fatty acids, such as butyric acid and propionic acid, are metabolic by-products generated by periodontal microflora such as Porphyromonas gingivalis, and contribute to the pathogenesis of periodontitis. However, the effects of butyrate on the biological activities of gingival fibroblasts (GFs) are not well elucidated. MATERIAL AND METHODS: Human GFs were exposed to various concentrations of butyrate (0.5-16 mm) for 24 h. Viable cells that excluded trypan blue were counted. Cell cycle distribution of GFs was analyzed by propidium iodide-staining flow cytometry. Cellular reactive oxygen species (ROS) production was measured by flow cytometry using 2',7'-dichlorofluorescein (DCF). Total RNA and protein lysates were isolated and subjected to RT-PCR using specific primers or to western blotting using specific antibodies, respectively. RESULTS: Butyrate inhibited the growth of GFs, as indicated by a decrease in the number of viable cells. This event was associated with an induction of G0/G1 and G2/M cell cycle arrest by butyrate (4-16 mm) in GFs. However, no marked apoptosis of GFs was noted in this experimental condition. Butyrate (> 2 mm) inhibited the expression of cdc2, cdc25C and cyclinB1 mRNAs and reduced the levels of Cdc2, Cdc25C and cyclinB1 proteins in GFs, as determined using RT-PCR and western blotting, respectively. This toxic effect of butyrate was associated with the production of ROS. CONCLUSION: These results suggest that butyrate generated by periodontal pathogens may be involved in the pathogenesis of periodontal diseases via the induction of ROS production and the impairment of cell growth, cell cycle progression and expression of cell cycle-related genes in GFs. These events are important in the initiation and prolongation of inflammatory processes in periodontal diseases.


Assuntos
Butiratos/farmacologia , Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Butiratos/toxicidade , Proteína Quinase CDC2 , Técnicas de Cultura de Células , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Corantes , Ciclina B/efeitos dos fármacos , Ciclina B1/efeitos dos fármacos , Quinases Ciclina-Dependentes , Fibroblastos/citologia , Citometria de Fluxo , Fluoresceína-5-Isotiocianato , Fluoresceínas , Corantes Fluorescentes , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Gengiva/citologia , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Propídio , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Fosfatases cdc25/efeitos dos fármacos
5.
Br J Cancer ; 103(7): 954-60, 2010 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-20808309

RESUMO

BACKGROUND: Human hepatocellular carcinoma (HCC) cells are largely deficient of argininosuccinate synthetase and thus auxotrophic for arginine. This study aims to investigate the efficacy and pharmacodynamics of pegylated arginine deiminase (ADI-PEG 20), a systemic arginine deprivation agent, in Asian HCC patients. METHODS: Patients with advanced HCC who were not candidates for local therapy were eligible and randomly assigned to receive weekly intramuscular injections of ADI-PEG 20 at doses of 160 or 320 IU m(-2). The primary end point was disease-control rate (DCR). RESULTS: Of the 71 accruals, 43.6% had failed previous systemic treatment. There were no objective responders. The DCR and the median overall survival (OS) of the intent-to-treat population were 31.0% (95% confidence interval (CI): 20.5-43.1) and 7.3 (95% CI: 4.7-9.9) months respectively. Both efficacy parameters were comparable between the two study arms. The median OS of patients with undetectable circulating arginine for more than or equal to and <4 weeks was 10.0 (95% CI: 2.1-17.9) and 5.8 (95% CI: 1.4-10.1) months respectively (P=0.251, log-rank test). The major treatment-related adverse events were grades 1-2 local and/or allergic reactions. CONCLUSIONS: ADI-PEG 20 is safe and efficacious in stabilising the progression of heavily pretreated advanced HCC in an Asian population, and deserves further exploration.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Hidrolases/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Polietilenoglicóis/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Arginina/sangue , Povo Asiático , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Retratamento
6.
Biomed Microdevices ; 12(1): 107-14, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19830566

RESUMO

The glass-based microfluidic chip has widely been applied to the lab-on-a-chip for clotting tests. Here, we have demonstrated a capillary driven flow chip using the water-assisted CO(2) laser ablation for crackless fluidic channels and holes as well as the modified low-temperature glass bonding with assistance of adhesive polymer film at 300 degrees Celsius. Effect of water depth on the laser ablation of glass quality was investigated. The surface hydrophilic property of glass and polymer film was measured by static contact angle method for hydrophilicity examination in comparison with the conventional polydimethylsiloxane (PDMS) material. Both low-viscosity deionized water and high-viscosity whole blood were used for testing the capillary-driving flow behavior. The preliminary coagulation testing in the Y-channel chip was also performed using whole blood and CaCl(2) solution. The water-assisted CO(2) laser processing can cool down glass during ablation for less temperature gradient to eliminate the crack. The modified glass bonding can simplify the conventional complex fabrication procedure of glass chips, such as high-temperature bonding, long consuming time and high cost. Moreover, the developed fluidic glass chip has the merit of hydrophilic behavior conquering the problem of traditional hydrophobic recovery of polymer fluidic chips and shows the ability to drive high-viscosity bio-fluids.


Assuntos
Materiais Biocompatíveis/química , Biotecnologia/instrumentação , Vidro/química , Lasers de Gás , Técnicas Analíticas Microfluídicas/instrumentação , Materiais Biocompatíveis/efeitos da radiação , Ação Capilar , Desenho de Equipamento , Análise de Falha de Equipamento , Vidro/efeitos da radiação , Temperatura Alta
7.
Int Endod J ; 41(5): 442-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18217994

RESUMO

AIM: To report two cases of palatal root fracture in maxillary molars that were successfully managed in the short term by root canal treatment and root amputation. SUMMARY: In the first case, a 48-year-old woman with bony destruction and a deep periodontal pocket on the palatal root of tooth 26 (FDI) underwent root canal treatment. Bleeding into the palatal canal and radiolucent lines over the root suggested a fracture. Further evidence was provided by an electronic apex locator. Subsequent surgery confirmed the presence of a horizontal root fracture and the fractured root was removed. In the second case, a 75-year-old woman presented with pain from the left posterior teeth. Clinical examination revealed an oblique root fracture of tooth 27 palatal roots with abscess formation and a deep periodontal pocket. Palatal root amputation and odontoplasty were performed. This was followed by root canal treatment. Both teeth were preserved in the short term and early healing of these two cases was uneventful. KEY LEARNING POINTS: Horizontal/oblique root fracture of the palatal root in molars is rare. A combination of periodontal and root canal treatment and palatal root amputation may allow short-term preservation of functional teeth.


Assuntos
Periodontite Periapical/complicações , Bolsa Periodontal/complicações , Fraturas dos Dentes/etiologia , Raiz Dentária/lesões , Raiz Dentária/cirurgia , Idoso , Feminino , Humanos , Maxila , Pessoa de Meia-Idade , Dente Molar/lesões , Dente Molar/cirurgia , Tratamento do Canal Radicular , Fraturas dos Dentes/cirurgia
8.
Eur J Oncol Nurs ; 35: 62-66, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30057085

RESUMO

PURPOSE: Research on symptom clusters is a newly emerging field in oncology; however, little evidence regarding symptom clusters in head and neck cancer (HNC) is currently available. To clarify this under-researched area, we investigated symptom clusters among patients with HNC treated with surgery and postoperative radiotherapy. We also examined the pattern of symptom clusters throughout the treatment course. METHOD: A convenience sample of 100 patients with HNC was recruited in the Ear, Nose, and Throat unit of a medical center in Taiwan. Before undergoing postoperative radiotherapy, patients were asked to complete the MD Anderson Symptom Inventory and a demographic sheet. Patients completed the same inventory questionnaire at week 1, 2, 3, 4, 5, and 6 of radiotherapy. RESULT: Two symptom clusters were observed, and they were stable throughout the course of radiotherapy. Cluster 1, the HNC-specific cluster, comprised the symptoms of pain, dry mouth, lack of appetite, sleep disturbance, fatigue, drowsiness, distress, and sadness. Cluster 2, the gastrointestinal cluster, included nausea, vomiting, numbness, shortness of breath, and difficulty remembering. CONCLUSION: This study advanced our knowledge of symptom clusters in patients with HNC. The results are expected to contribute to the development of appropriate assessment and nursing interventions targeting multiple symptoms that may coexist in postoperative radiotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Radioterapia/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Inquéritos e Questionários , Síndrome , Taiwan
9.
AJNR Am J Neuroradiol ; 28(6): 1042-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17569953

RESUMO

BACKGROUND AND PURPOSE: The purpose of this study was to investigate the risk factors for new symptomatic vertebral compression fractures after vertebroplasty at the thoracolumbar junction. MATERIALS AND METHODS: We conducted a retrospective analysis of 53 patients treated with percutaneous vertebroplasty at the thoracolumbar junction (T12, L1). The follow-up period was 15-27 months. The occurrence of new symptomatic vertebral compression fractures was recorded after vertebroplasty. We evaluated patient age and sex, amount of injected cement, vacuum clefts in the collapsed bodies, initial wedge angle of the compression fracture, change of the wedge angle after vertebroplasty, intradiskal cement leak, and percentage of height restoration of the vertebral body. In this report, we surveyed the possible risk factors for new symptomatic vertebral compression fractures. RESULTS: Thirty-nine (74%) of the 53 patients had fluid and/or air in the compression fracture at the thoracolumbar junction (T12, L1). Eight (20.5%) of the 39 patients with vacuum clefts had new symptomatic compression fracture after vertebroplasty between 1 month and 4 days after surgery to 23 months and 4 days after surgery. The patients with new symptomatic compression fracture had higher initial wedge angle and wedge angle change (more than 7 degrees ) after vertebroplasty than those without fractures; these data were considered statistically significant. CONCLUSIONS: The incidence of vacuum clefts in the compression fracture at the thoracolumbar junction is high (74%). The severity of initial wedge angle and wedge angle change affects the incidence of new symptomatic compression fracture.


Assuntos
Fraturas por Compressão/epidemiologia , Metilmetacrilatos/uso terapêutico , Medição de Risco/métodos , Fraturas da Coluna Vertebral/epidemiologia , Vértebras Torácicas/lesões , Idoso , Feminino , Humanos , Incidência , Masculino , Fatores de Risco , Taiwan
10.
Water Sci Technol ; 55(1-2): 425-31, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17305167

RESUMO

This study examined the reuse potential of the effluents discharged from several unified wastewater treatment plants (WWTPs) of industrial parks in Taiwan, with designed capacity exceeding 10,000 CMD. Parameters were selected based on the relevant reuse purposes. The "potential recycling percentage", R of the WWTP effluent was defined as the maximal percentage of pure water extractable by the "ideal reverse osmosis module" while the RO retentate still met local effluent standards and required no treatment. The analytical results demonstrated that the WWTP effluents had potential for recycling. A pilot plant was installed in one of the WWTPs. The treatment process included a sand filter, an ultrafiltration unit (UF) and a reverse osmosis module (RO). Results of this study demonstrated that the production quantity and quality are stable and appropriate for various purposes, including both industrial and domestic applications.


Assuntos
Conservação dos Recursos Naturais/métodos , Resíduos Industriais , Eliminação de Resíduos Líquidos , Purificação da Água/métodos , Membranas Artificiais , Eliminação de Resíduos , Esgotos/química , Taiwan
11.
Biomed Mater ; 12(2): 025011, 2017 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-28177302

RESUMO

Successful regeneration of the cranium in patients suffering from cranial bone defects is an integral step to restore craniofacial function. However, restoration of craniofacial structure has been challenging due to its complex geometry, limited donor site availability, and poor graft integration. To address these problems, we investigated the use of a thiol-acrylate hydrogel as a cell carrier to facilitate cranial regeneration. Thiol-acrylate hydrogels were formulated with 5-15 wt% poly(ethylene glycol)-diacrylate (PEGDA) and 1-9 mm dithiothreitol (DTT). The degradation rate, swelling ratio, and shear modulus of the resulting hydrogel were first characterized. Then, pre-osteoblast-like cells (MC3T3-E1) were encapsulated in the hydrogel and cultured for up to 21 d. Our results demonstrate that compared to samples formulated from 15 wt% PEGDA, 5 wt% PEGDA samples showed lower storage modulus at day 10 (0.7 kPa versus 8.3 kPa), 62.7% higher in weight change after soaking for 10 d. While the 5 wt% PEGDA group showed an 85% weight loss between day 10 and 21, the 15 wt% PEGDA group showed a 5% weight gain in the same time period. Cell viability with 15 wt% PEGDA and 5 mm DTT hydrogel decreased by 41.3% compared to 5 wt% PEGDA and 5mM DTT gel at day 7. However, histological analysis of cells after 21 d in culture revealed that they had pericellular mineral deposition indicating that the cells were differentiating into osteoblasts lineage in all experimental groups. This study shows that thiol-acrylate hydrogels can be tailored to achieve different degradation rates, in order to enhance cell viability and differentiation. Thus, the findings of this study provide a fundamental understanding for the application of thiol-acrylate hydrogels in cranial bone regeneration.


Assuntos
Materiais Biocompatíveis/química , Regeneração/fisiologia , Crânio/fisiologia , Células 3T3 , Implantes Absorvíveis , Acrilatos/química , Animais , Fenômenos Biomecânicos , Calcificação Fisiológica , Diferenciação Celular , Sobrevivência Celular , Humanos , Hidrogéis/química , Teste de Materiais , Camundongos , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteoblastos/transplante , Polietilenoglicóis/química , Compostos de Sulfidrila/química , Engenharia Tecidual/métodos
13.
Biomaterials ; 81: 36-45, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26717247

RESUMO

PURPOSE: To determine whether a fish scale-derived collagen matrix (FSCM) meets the basic criteria to serve as an artificial cornea, as determined with in vitro and in vivo tests. METHODS: Primary corneal epithelial and stromal cells were obtained from human donor corneas and used to examine the (in)direct cytotoxicity effects of the scaffold. Cytotoxicity was assessed by an MTT assay, while cellular proliferation, corneal cell phenotype and adhesion markers were assessed using an EdU-assay and immunofluorescence. For in vivo-testing, FSCMs were implanted subcutaneously in rats. Ologen(®) Collagen Matrices were used as controls. A second implant was implanted as an immunological challenge. The FSCM was implanted in a corneal pocket of seven New Zealand White rabbits, and compared to sham surgery. RESULTS: The FSCM was used as a scaffold to grow corneal epithelial and stromal cells, and displayed no cytotoxicity to these cells. Corneal epithelial cells displayed their normal phenotypical markers (CK3/12 and E-cadherin), as well as cell-matrix adhesion molecules: integrin-α6 and ß4, laminin 332, and hemi-desmosomes. Corneal stromal cells similarly expressed adhesion molecules (integrin-α6 and ß1). A subcutaneous implant of the FSCM in rats did not induce inflammation or sensitization; the response was comparable to the response against the Ologen(®) Collagen Matrix. Implantation of the FSCM in a corneal stromal pocket in rabbits led to a transparent cornea, healthy epithelium, and, on histology, hardly any infiltrating immune cells. CONCLUSION: The FSCM allows excellent cell growth, is not immunogenic and is well-tolerated in the cornea, and thus meets the basic criteria to serve as a scaffold to reconstitute the cornea.


Assuntos
Estruturas Animais/química , Materiais Biocompatíveis/farmacologia , Córnea/efeitos dos fármacos , Córnea/imunologia , Animais , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colágeno/farmacologia , Substância Própria/citologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Epitélio Corneano/citologia , Feminino , Peixes , Glucose/metabolismo , Humanos , Fenótipo , Coelhos , Ratos Endogâmicos F344 , Resistência à Tração/efeitos dos fármacos
14.
Int J Oral Maxillofac Surg ; 44(7): 816-22, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25825373

RESUMO

A randomized controlled trial was designed to assess the effectiveness of two alar base cinch techniques on the changes in nasolabial morphology after bimaxillary orthognathic surgery. Sixty patients requiring a Le Fort I osteotomy to correct skeletal discrepancies were selected randomly to receive either conventional or modified alar base cinching during the intraoral wound closure procedure. Conventional cinching passed through nasalis muscle and anterior nasal spine. Modified cinching also passed through dermis tissue to increase the anchorage. Postoperative hard and soft tissue changes were evaluated using cone beam computed tomography and three-dimensional stereophotogrammetry at predefined time points. Forty-eight patients with a skeletal class III malocclusion were included. In the conventional group, there was an increase of 0.31 ± 1.31 mm in nasal width and an increase of 0.97 ± 1.60mm in columellar length. In the modified group, there was an increase of 0.81 ± 1.87 mm in the cutaneous height of the upper lip and a decrease of 0.76 ± 1.56 mm in lower prolabial width. Patients with an initial narrow nasal width, alar base width, and less vertical nostril show were more susceptible to a greater degree of change after surgery. Both alar base suture techniques are effective at controlling nasolabial form changes resulting from class III dual-jaw orthognathic surgery.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Má Oclusão Classe III de Angle/diagnóstico por imagem , Má Oclusão Classe III de Angle/cirurgia , Maxila/diagnóstico por imagem , Maxila/cirurgia , Nariz/diagnóstico por imagem , Nariz/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Técnicas de Sutura , Adulto , Antropometria , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Osteotomia de Le Fort , Estudos Prospectivos , Taiwan , Resultado do Tratamento
15.
Biomaterials ; 17(11): 1133-40, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8718975

RESUMO

Autogenous bone transfer is an important part of reconstructive plastic surgery. Presently available techniques have the disadvantages of limitation of available donor site, loss of donor tissue and the possibility of donor defect or deformity. In the present study, a vascularized bone graft was created and cultured in the groin area of the New Zealand rabbit. The cylindrical ceramic chambers, 15 mm in length, 6 mm in outer diameter and 3 mm in inner diameter, were prepared by the addition of sintered porous beta-Ca2P2O7 with 5 wt% Na4P2O7.10H2O. In the first group, the chambers impregnated with autogenous bone fragments and allogenous demineralized bone matrix with volume ratio 1:1 were cultured in the rabbit's groin area with saphenous vessels passing through. In the second group, the chambers were treated by the same procedures as the first group but without saphenous vessels passing through. In the third group, the chambers were not impregnated, and were cultured in the groin area with saphenous vessels. After 2, 4, 6, 8 and 12 wk of operation, the animals were killed with an overdose of intravenous pentobarbital. The viability of the osseous tissue in the chamber was evaluated by histological examination, microangiograms and fluorochrome incorporation for the three groups. The autogenous bone chips could survive and retain their osteogenic properties while packed into the sintered porous beta-Ca2P2O7 (with 5 wt% Na4P2O7.10H2O addition) ceramic chamber and implanted in the rabbit groin area up to 12wk. However, even at the longest time periods, considerable amounts of dead bone were present in the chambers. In addition, we observed bone resorption in the three groups up to 12 wk, which might be attributed to lack of physiological stress. There were significant differences in new bone formation and osseous cell viability among the three groups. The prevascularized vessels and autogenous bone chips were both necessary for the formation of new bone and osteogenic property in the chamber under these heterotopic circumstances. The biodegradable ceramic used in this study was gradually absorbed and dissolved in the physiological environment. However, the degradation debris of the ceramic caused no injury to the new bone formation. These findings support the concept of creating a preformed vascularized bone graft to reconstruct segmental bone defects.


Assuntos
Materiais Biocompatíveis , Transplante Ósseo/métodos , Osso e Ossos/irrigação sanguínea , Pirofosfato de Cálcio , Cerâmica , Difosfatos , Animais , Técnica de Desmineralização Óssea , Osso e Ossos/citologia , Sobrevivência Celular/fisiologia , Histocitoquímica , Masculino , Coelhos
16.
Biomaterials ; 16(10): 793-802, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7492710

RESUMO

The ultimate goal of implantation of biomaterials in the skeleton is to reach full integration of the non-living implant with the living bone. The biomaterial can be used much as a bone graft, resorbing or dissolving as bone growth occurs, and the end result is a new remoulded bone. Calcium pyrophosphate, Ca2P2O7, is one of the intermediate products of bone mineralization. beta-Dicalcium pyrophosphate (beta-DCP) doped with certain amounts of Na4P2O7.10H2O was prepared as the developed material. Na4P2O7.10H2O was used as a liquid-phase additive to improve the sintering process and promote physiological bioresorbability. Compressive strength and four-point bending strength were measured by the Bionix test system 858. The mechanical strength of the sintered beta-DCP increased with the addition of Na4P2O7.10H2O up to 5 wt%, but thereafter decreased. The microstructure and crystal structure were analysed by the techniques of SEM, EPMA, TEM and XRD. The relationship between the mechanical strength of the sintered bioceramics and the Na4P2O7.10H2O dopant was examined in terms of the presence of NaCa(PO3)3, grain growth and abnormal grain coalescence while the dopant increased. Preliminary in vivo evaluation was studied by rabbit femur condyle implantation. There was no inflammation or any toxic sign during the experimental period. The histological section of intraosseous implantation revealed that the new bone deposited directly on the surface of the material in the fourth week after operation. The implant gradually decreased in volume and was replaced by the surrounding regenerated bone in the rabbit condyle in vivo environment. The results led us to conclude that the developed material has great potential as a biodegradable bone substitute.


Assuntos
Substitutos Ósseos , Osso e Ossos/patologia , Animais , Substitutos Ósseos/efeitos adversos , Calcificação Fisiológica , Pirofosfato de Cálcio/toxicidade , Cerâmica/toxicidade , Difosfatos/toxicidade , Fêmur/patologia , Fêmur/ultraestrutura , Masculino , Teste de Materiais , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Coelhos , Estresse Mecânico , Resistência à Tração
17.
Biomaterials ; 15(13): 1087-98, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7888580

RESUMO

There is extensive experimental and surgical experience with the use of bone tissue to fill defects in the skeleton, to bridge non-union sites, and to pack defects in bone created from cyst curettage. DP-bioactive glass with a chemical composition of Na2O 8.4%, SiO2 39.6%, P2O5 12% and CaO 40% has been reported as an alternative bone substitute of high mechanical strength, good biocompatibility. and which has a tight bond with living tissue. The bonding layer between DP-bioactive glass and bone tissue was considered to be formed by dissolution of calcium and phosphate ions from the DP-bioactive glass into the surrounding body fluids. The biological hydroxyapatite was suspected to deposit directly onto the bonding layer. In order to confirm the interaction between the DP-bioactive glass and bone tissue, the developed bioactive glass was implanted into rabbit femur condyle for 2-32 weeks. The histological evaluation of DP-bioactive glass as a bone substitute was also investigated in the study. Porous hydroxyapatite bioceramic was used in the control group and the results were compared with those of DP-bioactive glass. The interface between the DP-bioactive glass and bone tissue examined with SEM-EPMA showed that the bioactive glass formed a reaction layer on the surface within 2 weeks after operation and formed a direct bond with natural bone. The elements contained in the bioactive glass apparently interdiffuse with the living bone and biological hydroxyapatite deposited onto the diffusion area, which was proved by EPMA and TEM. After implantation for over 8 weeks, the DP-bioactive glass was gradually biodegraded and absorbed by the living bone. Histological examination using the optical microscope showed that osteocytes grow into the inside of the DP-bioactive glass and the bioactive glass would be expected to be a part of bone.


Assuntos
Regeneração Óssea , Substitutos Ósseos/normas , Fêmur/ultraestrutura , Vidro/química , Hidroxiapatitas/química , Animais , Fenômenos Biomecânicos , Líquidos Corporais/metabolismo , Compostos de Cálcio/metabolismo , Difusão , Microanálise por Sonda Eletrônica , Fêmur/fisiologia , Hidroxiapatitas/metabolismo , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Óxidos de Nitrogênio/metabolismo , Óxidos/metabolismo , Fósforo/metabolismo , Próteses e Implantes , Coelhos , Dióxido de Silício/metabolismo , Temperatura , Difração de Raios X
18.
J Microbiol Immunol Infect ; 32(3): 213-6, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10637721

RESUMO

A uremic patient developed subhepatic abscess, Porphyromonas gingivalis bacteremia and cytomegalovirus viremia after a renal transplantation in mainland China. P. gingivalis infection has been reported to cause gingivitis and periodontitis. Bacteremia due to P. gingivalis, however, has not been reported in the literature. We report herein a case of subhepatic abscess and bacteremia due to P. gingivalis in a renal transplant recepient who was treated successfully with the well functioning renal graft.


Assuntos
Abscesso/etiologia , Bacteriemia/etiologia , Infecções por Bacteroidaceae/etiologia , Transplante de Rim/efeitos adversos , Porphyromonas gingivalis/isolamento & purificação , Adulto , Infecções por Citomegalovirus/etiologia , Humanos , Masculino , Viremia/etiologia
19.
J Pharm Pharmacol ; 53(2): 187-91, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11273014

RESUMO

Reactive oxygen species have been implicated as important pathological mediators in many clinical disorders, including periodontal disease. As a possible alternative for the treatment of periodontal disease, the antimicrobial activity of six tannins isolated from Vaccinium vitis-idaea L., with confirmed antioxidant activity, were assayed by the agar dilution method against selected periodontal pathogens, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia. The results showed that epicatechin-(4beta-->8)-epicatechin-(4beta-->8, 2beta-->O-->7)-catechin had strong antimicrobial activity against P. gingivalis and P. intermedia, but not A. actinomycetemcomitans. The other tannins tested did not show antimicrobial activity. We conclude that tannins isolated from V. vitis-idaea L. with antimicrobial activity could potentially be used for the treatment of periodontal disease.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Plantas Medicinais/química , Taninos/farmacologia , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Doenças Periodontais/microbiologia , Porphyromonas gingivalis/efeitos dos fármacos , Prevotella intermedia/efeitos dos fármacos , Taninos/química , Taninos/isolamento & purificação
20.
J Pharm Pharmacol ; 51(9): 1075-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10528992

RESUMO

Reactive oxygen molecules have been implicated as important pathological mediators in many clinical disorders and periodontal disease. To provide possible alternative treatment of periodontal disease, six tannins isolated from Vaccinium vitis-idaea L. were evaluated for anti-lipid peroxidation, anti-superoxide formation and free radical scavenging activity. The results showed that cinnamtannin B1 displayed the strongest anti-lipid peroxidation activity, proanthocyanidin A-1 displayed the strongest superoxide scavenging activity, and epicatechin-(4beta--> 6)-epicatechin-(4beta-->8, 2beta-->O--> 7)-catechin had the strongest anti-superoxide formation effect. We conclude that tannins isolated from V. vitis-idaea L. exhibited multiple antioxidant activity, and could be used for the treatment of periodontal disease.


Assuntos
Antioxidantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Taninos/farmacologia , Antioxidantes/isolamento & purificação , Doenças Periodontais/prevenção & controle , Extratos Vegetais/isolamento & purificação , Espécies Reativas de Oxigênio , Relação Estrutura-Atividade , Superóxidos , Taninos/isolamento & purificação , Xantina Oxidase/antagonistas & inibidores
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