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1.
Ann Vasc Surg ; 85: 190-203, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35337927

RESUMO

BACKGROUND: To evaluate the association of perioperative inflammatory status, as determined using the neutrophil-to-lymphocyte ratio (NLR) and high-sensitivity C-reactive protein (hs-CRP) level, with the efficacy of femoropopliteal paclitaxel-coated balloon (PCB) angioplasty. METHODS: The data of 122 patients (138 limbs) were retrospectively analyzed (median follow-up time, 21 months). The pre- and postoperative NLRs and hs-CRP levels were evaluated to determine their predictive value for mid-term primary patency and clinically driven target lesion revascularization (CD-TLR) during follow-up. Cox regression and Kaplan-Meier survival analyses were performed to investigate the predictive value of the inflammatory parameters and clinical risk factors. RESULTS: The study population had a median age of 67.2 ± 9.2 years, and 85.2 ± 3% of them were men. Approximately, 18.0 ± 3% of the cases were classified under Rutherford grade II; 52.5 ± 4%, grade III; 24.6 ± 3%, grade IV; 4.1 ± 1%, grade V; and 0.8 ± 0.7%, grade VI. The 12- and 24-month cumulative patency rates were 81.2 ± 27.0% and 60.4 ± 30.1%, respectively, and the freedom from CD-TLR rates were 90.8 ± 19.1% and 82.5 ± 28.3%, respectively. Severe lesion calcification was identified as an independent risk factor for CD-TLR (hazard ratio [HR] = 1.51, 95% confidence interval [CI] = 1.05-3.01), while hypertension was found as a protective factor for primary patency (HR = 0.54, 95% CI = 0.30-0.93). The patients with Trans-Atlantic Inter-Society Consensus (TASC) C/D lesions had more than a 2-fold increased adjusted risk of both primary patency loss and CD-TLR compared with those with TASC A/B lesions (HR = 2.44 for primary patency loss; HR = 2.51 for CD-TLR). The perioperative NLRs and hs-CRP levels were stratified into three grades. The patients with a higher preoperative hs-CRP level (>9.2 vs. 0.6-9.2 vs. <0.6 mg/L by each tertile) had a 2.4-fold increased adjusted risk of primary patency loss compared with those with a lower preoperative hs-CRP level. The patients with a higher hs-CRP level on the first postoperative day (>13.0 vs. 7.7-13.0 vs. <7.7 mg/L by each tertile) had a 1.8-fold increased adjusted risk of primary patency loss compared with those with a lower hs-CRP level. In contrast, the patients with a higher NLR at 4-6 hr postoperatively (>3.6 vs. 2.5-3.6 vs. <2.5 by each tertile) showed better primary patency (adjusted HR = 0.57) than did those with a lower NLR. A higher hs-CRP level on the first postoperative day was the only inflammatory marker associated with a high risk of CD-TLR (adjusted HR = 2.37). CONCLUSIONS: Perioperative inflammatory status serves as a valuable prognostic parameter for assessing the potential risk stratification of outcomes after paclitaxel-coated balloon (PCB) angioplasty.


Assuntos
Angioplastia com Balão , Doença Arterial Periférica , Idoso , Angioplastia com Balão/efeitos adversos , Proteína C-Reativa , Materiais Revestidos Biocompatíveis , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel/efeitos adversos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/etiologia , Doença Arterial Periférica/terapia , Artéria Poplítea/diagnóstico por imagem , Estudos Retrospectivos , Resultado do Tratamento , Grau de Desobstrução Vascular
2.
Curr Med Chem ; 28(40): 8243-8266, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33334278

RESUMO

BACKGROUND: Natural biopolymers have drawn extensive attention because of their great biocompatibility, biodegradability, renewability, and the availability of various reactive functional groups for modifying and introducing novel components. In the last few years, numerous natural biopolymer composites have been exploited to improve their physical and chemical properties and add new functionalities. METHODS: Herein, we summarize the current progress in three common classes of natural biopolymer-based composites, including alginate, chitosan, and gelatin. RESULTS: The morphology characteristics, preparation methods, and unique functionalities of these biopolymer composites are also analyzed and discussed. CONCLUSION: Finally, the article offers an overview of recent progress in the main biomedical applications such as tissue engineering, wound-healing, and drug delivery, which inspires further progress in biopolymer composites with tailored mechanical property and stable characteristics for pharmaceutical and biomedical applications.


Assuntos
Quitosana , Alginatos , Biopolímeros , Sistemas de Liberação de Medicamentos , Humanos , Engenharia Tecidual
3.
Curr Pharm Des ; 23(35): 5292-5300, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29086678

RESUMO

Cellulose is an important environmentally-friendly renewable polymer on the earth. Cellulose has been widely used as feedstocks for the synthesis of biomaterials, biofuels and biochemicals. Recently, cellulose and cellulose derivatives have received intense attention in biomedical applications, such as tissue engineering, scaffold, artificial blood vessel, skin grafts, artificial skin, drug carrier, and chronic skin diseases, many of which are somehow related to cancer therapy. In this mini-review, we focus on the up-to-date development of cellulosebased nanocarriers used for cancer therapy. Various cellulose-based nanocarriers such as bacterial cellulose (BC), cellulose acetate, microcrystalline cellulose, carboxymethyl cellulose, cellulose nanocrystals, cellulose nanofibrills, etc, are reviewed in terms of being used in drug delivery systems for cancer treatment. Different strategies for the synthesis of cellulose-based nanocarriers are summarized. Special attention is paid on the structure and properties of cellulose-based drug carriers for cancer therapy via some representative examples. Finally, the problems and future developments of these promising polymeric nanocarriers are raised and proposed.


Assuntos
Antineoplásicos/administração & dosagem , Celulose/administração & dosagem , Portadores de Fármacos/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/metabolismo , Celulose/metabolismo , Portadores de Fármacos/metabolismo , Humanos , Nanopartículas/metabolismo , Neoplasias/metabolismo
4.
J Phys Chem B ; 110(17): 8593-7, 2006 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-16640412

RESUMO

Polyacrylamide-metal (M = Pt, Ag, Cu) nanocomposites with metal nanoparticles homogeneously dispersed in the polymer matrix have been successfully prepared with the corresponding metal salt and acrylamide monomer in ethylene glycol by microwave heating. This method is based on the single-step simultaneous formation of metal nanoparticles and polymerization of the acrylamide monomer, leading to a homogeneous distribution of metal nanoparticles in the polyacrylamide matrix. Ethylene glycol acts as both a reducing reagent and a solvent, thus no additional reductant is needed. Another advantage is that no initiator for AM polymerization and no surfactant for stabilization of metal nanoparticles are necessary. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), ultraviolet visible (UV-vis) absorption spectra, and thermogravimetric (TG) and differential scanning calorimetric analysis (DSC).


Assuntos
Resinas Acrílicas/química , Etilenoglicol/química , Metais Pesados/química , Nanoestruturas/química , Compostos Organometálicos/síntese química , Resinas Acrílicas/efeitos da radiação , Cristalografia por Raios X , Etilenoglicol/efeitos da radiação , Metais Pesados/efeitos da radiação , Microscopia Eletrônica de Transmissão/métodos , Micro-Ondas , Nanoestruturas/efeitos da radiação , Compostos Organometálicos/química , Compostos Organometálicos/efeitos da radiação , Tamanho da Partícula , Sensibilidade e Especificidade , Propriedades de Superfície
5.
Dent Mater J ; 35(5): 756-761, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27725512

RESUMO

To assess the effect of resin infiltration vs. fluoride varnish in enhancing enamel surface conditions after interproximal reduction (IPR). After IPR procedures, 84 human enamel specimens were divided into three groups, group A/ group B was treated by fluoride varnish/resin infiltration according to the manufacturers' instructions, group C were treated with nothing. All the specimens were pH-cycled twice daily in 37°C bath for 30 days. Surface micro-hardness, density and mineral loss were measured before and after the pH cycling. The data were analyzed and compared using ANOVA. Both treatments A and B increased the surface microhardness of enamel after IPR (p<0.05). Both before and after pH cycling, the surface microhardness of A was significantly harder than B. The density of A was higher than B before pH cycling (p<0.05). Fluoride varnish and resin infiltration may provide an enamel protection from acid challenge.


Assuntos
Fluoretos Tópicos , Esmalte Dentário , Fluoretos , Dureza , Humanos
6.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 32(2): 88-92, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-30024681

RESUMO

Objective: To investigate the application of the digital osteotomy template in the mandibular angle osteotomy,so as to increase the precision and symmetry of the osteotomy. Methods: 8 cases were included in our study (female,average age 25.5).The CT data (DICOM format) were reformatted into 3D images using 3D imaging software (ProPlan).The osteotomy lines were designed on digital 3D theoretical model with ProPlan.Then the statistics of the ostectomy were imported into GeoMagic in the form of STL file to design the 3D osteotomy template.The osteotomy template was fabricated with FDA certificated PLA through RP machine. During operation,the template was inserted into operation area to guide the osteotomy.A line was drawn along the edge of ostectomy plate with a grinding ball and osteotomy was done along the curvilinear line using a goose saw. Results: The removed bone proved to be highly matched with the template.All the post-operative results were satisfactory.There were no complications such as fracture,life-threatening hemorrhage and infection.The post-operative measurement showed good symmetry. Conclusions: With the guidance of osteotomy templates,the surgeon can perform the osteotomy in an accurate way.The precision and symmetry of the osteotomy are greatly improved.


Assuntos
Mandíbula/cirurgia , Osteotomia/métodos , Adulto , Placas Ósseas , Desenho Assistido por Computador , Feminino , Humanos , Imageamento Tridimensional/métodos , Mandíbula/diagnóstico por imagem , Modelos Anatômicos , Osteotomia/instrumentação , Tomografia Computadorizada por Raios X/métodos
7.
Carbohydr Polym ; 91(1): 162-8, 2013 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-23044118

RESUMO

The purpose of this study is to develop a green strategy to synthesize the cellulose-based nanocomposites and open a new avenue to the high value-added applications of biomass. Herein, we reported a microwave-assisted ionic liquid route to the preparation of cellulose/CuO nanocomposites, which combined three major green chemistry principles: using environmentally friendly method, greener solvents, and sustainable resources. The influences of the reaction parameters including the heating time and the ratio of cellulose solution to ionic liquid on the products were discussed by X-ray powder diffraction, Fourier transform infrared spectrometry, and scanning electron microscopy. The crystallinity of CuO increased and the CuO shape changed from nanosheets to bundles and to particles with increasing heating time. The ratio of cellulose solution to ionic liquid also affected the shapes of CuO in nanocomposites. Moreover, CuO crystals were obtained by thermal treatment of the cellulose/CuO nanocomposites at 800 °C for 3 h in air.


Assuntos
Celulose/química , Cobre/química , Temperatura Alta , Líquidos Iônicos/química , Micro-Ondas , Nanocompostos/química , Ar , Técnicas de Química Sintética , Soluções
8.
Mater Sci Eng C Mater Biol Appl ; 32(6): 1511-7, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24364953

RESUMO

Nanocomposites of cellulose/iron oxide have been successfully prepared by hydrothermal method using cellulose solution and Fe(NO3)3·9H2O at 180 °C. The cellulose solution was obtained by the dissolution of microcrystalline cellulose in NaOH/urea aqueous solution, which is a good system to dissolve cellulose and favors the synthesis of iron oxide without needing any template or other reagents. The phases, microstructure, and morphologies of nanocomposites were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectra (EDS). The effects of the heating time, heating temperature, cellulose concentration, and ferric nitrate concentration on the morphological behavior of products were investigated. The experimental results indicated that the cellulose concentration played an important role in both the phase and shape of iron oxide in nanocomposites. Moreover, the nanocomposites synthesized by using different cellulose concentrations displayed different thermal stabilities.


Assuntos
Celulose/química , Compostos Férricos/química , Nanocompostos/química , Microscopia Eletrônica de Varredura/métodos , Nitratos/química , Soluções/química , Temperatura , Difração de Raios X/métodos
9.
Recent Pat Nanotechnol ; 4(3): 164-70, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20707769

RESUMO

Calcium-based inorganic biodegradable nanomaterials (CIBNs) including calcium phosphate, hydroxyapatite (HA), calcium silicate, calcium carbonate, and calcium sulfate, are important materials and have been widely used in biomedical field. Although CIBNs have been intensively studied, there are only a few synthesis methods that showed promising characteristics for practical applications. Here, we intend to review recent progress in the synthesis of the CIBNs including both patents and papers. In addition, the mechanisms of CIBNs are introduced. Finally, the current and future developments are put forward. In summary, we briefly review the patents and the patent-interrelated papers concerning the fabrication, mechanism, and future development of CIBNs in this mini-review. The paper provides an overview about the potential application of nanotechnology in biomedical field.


Assuntos
Materiais Biocompatíveis/química , Compostos de Cálcio/química , Nanoestruturas/química , Microscopia Eletrônica de Varredura , Nanoestruturas/ultraestrutura , Nanotecnologia/legislação & jurisprudência , Patentes como Assunto
10.
Carbohydr Res ; 345(8): 1046-50, 2010 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-20381016

RESUMO

Preparation of nanocomposites was carried out using microcrystalline cellulose, CaCl(2), and NaH(2)PO(4) in N,N-dimethylacetamide (DMAc) solvent by a microwave-assisted method at 150 degrees C. XRD results showed that the nanocomposites consisted of cellulose and hydroxyapatite (HA). The cellulose existed as a matrix in the nanocomposites. SEM and TEM analysis showed that HA nanorods were homogeneously dispersed in the cellulose matrix. The effects of the microwave heating time on the products were investigated. This method has advantages of being simple, rapid, low-cost, and environmentally friendly.


Assuntos
Acetamidas/química , Celulose/química , Durapatita/química , Micro-Ondas , Nanocompostos/química , Solventes/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanocompostos/ultraestrutura
11.
J Vasc Surg ; 37(5): 1075-81, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12756357

RESUMO

OBJECTIVES: R136K is a mutation of fibroblast growth factor-1 (FGF-1) in which arginine replaces lysine at the primary thrombin cleavage site. This may be important in vivo in inducing endothelial cell (EC) migration and coverage of arterial injury sites by allowing R136K to be used in a fibrin glue delivery system, without thrombin-induced degradation, in the absence of heparin. The objectives of this study were to determine whether R136K, with and without heparin, can induce migration of EC and smooth muscle cells (SMC) through fibrin glue, and to compare these results with those of wild-type FGF-1; and to determine the resistance of R136K to thrombin-induced degradation versus FGF-1. METHODS: The dose-response migration through fibrin glue induced by wild-type FGF-1 and the R136K mutant in the presence and absence of heparin was tested with EC and SMC. Migration was tested with 50, 100, and 200 ng/mL of both FGF-1 and R136K, either with or without 5 U/mL of heparin. Migration of EC was also assessed after growth inhibition with mitomycin C. A novel modified Boyden chamber-type migration assay using fibrin glue on the upper surface of the chamber filter was used to test migration. The fluorescent marker calcein was used to identify those cells that had migrated through the fibrin glue and were embedded in the filter. Molecular degradation by thrombin was assessed with sodium dodecylsulfate polyacrylamide gel electrophoresis. RESULTS: For EC, R136K in the absence of heparin induced significantly more migration than did FGF-1 at 50 (P <.002), 100 (P <.0001), and 200 (P <.0001) ng/mL. In the presence of heparin, a chemotactic response of EC to cytokine was seen at all doses, with no significant difference between FGF-1 and R136K. A dose-dependent difference was noted in this group between the 100 and 200 ng/mL concentrations of cytokine (for FGF-1, P <.0001; for R136K, P <.0001). SMC showed no difference in migration with FGF-1, R136K, or negative control at any dose in the presence or absence of heparin. Gel electrophoresis demonstrated that R136K was more resistant to thrombin degradation than was FGF-1. CONCLUSION: Site-directed mutagenesis of FGF-1 to R136K enables induction of heparin-independent migration of EC through fibrin glue at an optimal concentration of 100 ng/mL. Neither FGF-1 nor R136K elicits SMC migration through fibrin glue. The ability of R136K to induce EC migration through fibrin glue in the absence of heparin may prove useful in vivo by inducing EC migration and coverage of arterial injury sites, thus potentially reducing thrombogenicity and intimal hyperplasia.


Assuntos
Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Adesivo Tecidual de Fibrina/administração & dosagem , Fibrinolíticos/administração & dosagem , Fator 1 de Crescimento de Fibroblastos/administração & dosagem , Heparina/administração & dosagem , Adesivos Teciduais/administração & dosagem , Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Citocinas/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Trombina/efeitos dos fármacos , Trombina/metabolismo
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