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1.
Artigo em Inglês | MEDLINE | ID: mdl-38526751

RESUMO

Vaccines against SARS-CoV-2 have been recommended across the world, yet no study has investigated whether COVID-19 vaccination influences short-term warfarin anti-coagulation levels. Patients on stable warfarin treatment who received anti-SARS-CoV-2 vaccination were prospectively enrolled and followed up for three months. INR values less than 10 days before vaccination (baseline), 3-5 days (short-term) and 6-14 days (medium-term) after vaccination were recorded as INR0, INR1, and INR2, respectively. The variations of INR values within individuals were compared, and the linear mixed effect model was used to evaluate the variations of INR values at different time points. Logistic regression analysis was performed to determine covariates related to INR variations after COVID-19 vaccination. Vaccination safety was also monitored. There was a significant difference in INR values between INR0 and INR1 (2.15 vs. 2.26, p = 0.003), yet no marked difference was found between INR0 and INR2. The linear mixed effect model also demonstrated that INR variation was significant in short-term but not in medium-term or long-term period after vaccination. Logistic regression analysis showed that no investigated covariates, including age, vaccine dose, genetic polymorphisms of VKORC1 and CYP2C9 etc., were associated with short-term INR variations. Two patients (2.11%) reported gingival hemorrhage in the short-term due to increased INR values. The overall safety of COVID-19 vaccines for patients on warfarin was satisfying. COVID-19 vaccines may significantly influence warfarin anticoagulation levels 3-5 days after vaccination. We recommend patients on warfarin to perform at least one INR monitoring within the first week after COVID-19 vaccination.

2.
Blood Purif ; 53(6): 486-492, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38198755

RESUMO

INTRODUCTION: The objective of this study was to report our experience of angioplasty with paclitaxel-coated balloon (PCB) versus common balloon (CB) for the treatment of repeated failing vascular access. METHODS: Retrospective, single-center analysis consisting of 88 patients treated with percutaneous transluminal angioplasty in the period from October 2020 through December 2021. Patients were divided into two groups according to the type of treatment as PCB (n = 41) and CB (n = 47). We analyzed target lesion primary patency and vascular access primary patency for 6 months and the rate of complications. RESULTS: There was no significant difference in the target lesion primary patency which was similar for 6 months between the two groups (PCB group vs. CB group at 1, 3, and 6 months; 95.12 vs. 89.36% (p = 0.55), 75.61 versus 74.47% (p = 0.90), 53.66% versus 63.83% (p = 0.33), respectively). Similarly, vascular access primary patency in the PCB group and CB group was 90.24 and 89.36% (p = 0.83), respectively, at 1 month, 65.85 and 68.09% (p = 0.82), respectively, at 3 months, 39.02 and 53.19% (p = 0.18), respectively, at 6 months. There were no major complications after endovascular treatment. CONCLUSION: Compared to CB angioplasty, PCB angioplasty has no short-term patency benefit in the treatment of vascular access repeated stenosis.


Assuntos
Angioplastia com Balão , Paclitaxel , Diálise Renal , Grau de Desobstrução Vascular , Humanos , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Estudos Retrospectivos , Masculino , Feminino , Angioplastia com Balão/métodos , Pessoa de Meia-Idade , Idoso , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/terapia , Dispositivos de Acesso Vascular , Materiais Revestidos Biocompatíveis , Constrição Patológica
3.
Med Sci Monit ; 25: 2819-2834, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30994108

RESUMO

BACKGROUND The present study aimed to evaluate the difference in microbiota diversity in the oral cavity and fluid bronchoalveolar lavage (BALF) of patients with lung cancer. MATERIAL AND METHODS Buccal (saliva) and lower respiratory tract BALF samples were collected from 51 patients with primary bronchogenic carcinoma and 15 healthy controls, and bacterial genomic DNA was extracted. High-throughput 16S rDNA amplicon sequencing was performed, and microbial diversity, composition, and functions of microbiota were analyzed by bioinformatics methods. RESULTS Patients with lung cancer have lower microbial diversity than healthy controls in both saliva and BALF samples. Significant segregation was observed between the different pathological types of lung cancer groups and the control group regardless of the sampling site. Treponema and Filifactor were identified as potential bacterial biomarkers in BALF samples, while Filifactor was ideal to distinguish healthy controls from lung cancer patients. Moreover, the predictive variation analysis of the KEGG (Kyoto Encyclopedia of Genes and Genomes) metabolic pathway showed that the metabolic differences in microbiota varied by sampling site. CONCLUSIONS Lung cancer patients carry a different and less diverse microorganism community than healthy controls. Certain bacterial taxa might be associated with lung cancer, but the exact species depends on the sampling site and the pathological type. This study provides basic data on the microbiota diversity in BALF and saliva samples from lung cancer patients. Further investigation with a larger sample size should help validate the enriched species in different pathological types of lung cancers.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Carcinoma Broncogênico/microbiologia , Neoplasias Pulmonares/microbiologia , Saliva/microbiologia , Adulto , Idoso , Bactérias/genética , Bactérias/isolamento & purificação , Biomarcadores Tumorais/análise , Lavagem Broncoalveolar/métodos , Feminino , Humanos , Masculino , Microbiota , Pessoa de Meia-Idade , Dados Preliminares
4.
J Environ Sci (China) ; 86: 24-37, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31787188

RESUMO

Problems associated with water eutrophication due to high phosphorus concentrations and related environmentally safe solutions have attracted wide attention. A novel bis(diallyl alkyl tertiary ammonium salt) polymer, particularly poly(N1,N1,N6,N6-tetraallylhexane-1,6-diammonium dichloride) (PTAHDADC), was synthesized and characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, scanning electron microscopy, mercury intrusion method, and thermogravimetric analysis. The adsorption characteristics in phosphorus were evaluated in dilute solution, and the recycling properties of PTAHDADC were investigated. Results showed that PTAHDADC possessed macropores with a size distribution ranging from 30 to 130 µm concentrating at 63 µm in diameter and had 46.52% of porosity, excellent thermal stability below 530K, and insolubility. PTAHDADC could effectively remove phosphorus at pH = 7-11 and had a removal efficiency exceeding 98.4% at pH = 10-11. The adsorption equilibrium data of PTAHDADC for phosphorus accorded well with the Langmuir and pseudo-second-order kinetic models. Maximum adsorption capacity was 52.82 mg/g at 293 K. PTAHDADC adsorbed phosphorus rapidly and reached equilibrium within 90 min. Calculated activation energy Ea was 15.18 kJ/mol. PTAHDADC presented an excellent recyclability with only 8.23% loss of removal efficiency after five adsorption-desorption cycles. The morphology and structure of PTAHDADC slightly changed as evidenced by the pre- and post-adsorption of phosphorus, but the process was accompanied by the partial deprotonation of the (-CH2)3NH+ group of PTAHDADC. The adsorption was a spontaneous exothermic process driven by entropy through physisorption, electrostatic attraction, and ion exchange. Survey results showed that PTAHDADC was a highly efficient and fast-adsorbing phosphorus-removal material prospective in treating wastewater.


Assuntos
Compostos de Amônio/química , Fósforo/química , Polímeros/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Compostos de Amônio/análise , Águas Residuárias
5.
Aesthetic Plast Surg ; 39(1): 84-90, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25552330

RESUMO

PURPOSE: Puerperal breast abscess after polyacrylamide hydrogel (PAAG) augmentation mammoplasty can induce breast auto-inflation resulting in serious consequences. Mammography, ultrasound, and conventional MRI are poor at detecting related PAAG abnormality histologically. We evaluated the value of diffusion-weighted imaging (DWI) in the quantitative analysis of puerperal PAAG abscess after augmentation mammoplasty. MATERIALS AND METHODS: This was a retrospective study, and a waiver for informed consent was granted. Sixteen puerperal women with breast discomfort underwent conventional breast non-enhanced MRI and axial DWI using a 3T MR scanner. Qualitative analysis of the signal intensity on DWI and conventional sequences was performed. The apparent diffusion coefficient (ADC) values of the affected and contralateral normal PAAG cysts were measured quantitatively. Paired t test was used to evaluate whether there was significant difference. RESULTS: Both affected and normal PAAG cysts showed equal signal intensity on conventional T1WI and fat saturation T2WI, which were not helpful in detecting puerperal PAAG abscess. However, the affected PAAG cysts had a significantly decreased ADC value of 1.477 ± 0.332 × 10(-3)mm(2)/s and showed obvious hypo-intensity on the ADC map and increased signal intensity on DWI compared with the ADC value of 2.775 ± 0.233 × 10(-3)mm(2)/s of the contralateral normal PAAG cysts. CONCLUSION: DWI and quantitative measurement of ADC values are of great value for the diagnosis of puerperal PAAG abscess. Standardized MRI should be suggested to these puerperal women with breast discomfort or just for the purpose of check up. DWI should be selected as the essential MRI sequence.


Assuntos
Abscesso/diagnóstico , Abscesso/etiologia , Resinas Acrílicas , Doenças Mamárias/diagnóstico , Doenças Mamárias/etiologia , Implantes de Mama/efeitos adversos , Imagem de Difusão por Ressonância Magnética , Mamoplastia/efeitos adversos , Transtornos Puerperais/diagnóstico , Transtornos Puerperais/etiologia , Adulto , Estudos de Avaliação como Assunto , Feminino , Humanos , Estudos Retrospectivos , Adulto Jovem
6.
J Phys Condens Matter ; 23(2): 025501, 2011 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-21406842

RESUMO

We have investigated effects of O on mechanical properties of NiAl by calculating the cleavage energy (γ(C)) and the unstable stacking fault energy (γ(us)) using a first-principles method. O is shown to reduce γ(C)/γ(us) for the [001](110) and [100](001) slip systems, indicating that the presence of O should be associated with the ductility reduction of NiAl. Further, γ(C)/γ(us) of the NiAl-O system can be increased by Cr, suggesting the possibility to suppress the negative effect of O via alloying elements.


Assuntos
Compostos de Alumínio/química , Níquel/química , Oxigênio/química , Ligas/química
7.
Anal Methods ; 13(34): 3792-3798, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34355707

RESUMO

A new polythiophene-based optical probe, namely PTS, was designed and prepared for detection and quantification of the water present in organic solvents. PTS exhibited sensitive and fast absorption and fluorescence signaling response to the changes of water content in tetrahydrofuran (THF), N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMAc) due to the water-induced interpolymer-stacking aggregation as demonstrated by dynamic light scattering (DLS) analysis. The fluorescence intensity of PTS at 550 nm linearly reduced as a function of the water content in detection ranges of 0-30% (v/v) in THF, 0-10% in DMF and 0-10% in DMAc with the limit of detection (LOD) for water being 0.034% (v/v) in THF, 0.013% (v/v) in DMF, and 0.014% (v/v) in DMAc, respectively. Additionally, PTS-incorporated test paper was fabricated to successfully achieve naked-eye detection of water in DMF and DMAc. PTS was further applied to estimate the water content in real samples, convincingly demonstrating that our method was comparable with the standard Karl Fischer titration.


Assuntos
Dimetilformamida , Água , Polímeros , Solventes , Tiofenos
8.
Environ Pollut ; 288: 117745, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243083

RESUMO

Surface currents play an essential role in the worldwide distribution of microplastics in the coastal seas and open oceans. As a branch of the western boundary currents (WBCs), Kuroshio changes seawater properties and pollutant levels of the South China Sea (SCS) during its intrusion process. To study the impact of Kuroshio intrusion on microplastics, we conducted field observations on surface water from the western Pacific (WP) and SCS. Microplastic abundances in the surface water of WP (0.02-0.10 particles m-3) were generally lower than those in the SCS (0.05-0.26 particles m-3). Fragments and granules dominated their apparent characteristics, and showed spatial classifications in different areas. The abundance of fragment, granule and foam showed a similar unimodal trend, as they peaked when the Kuroshio fraction was 0.1, implying the effect of Kuroshio intrusion was a combination of the dilution and biogeochemical influence. The polymer types of microplastics, dominated by polypropylene (PP), polyethylene (PE), polyester (PES), polymethacrylate (PMA) and phenoxy resin (PR), showed complicated compositions in the northern SCS, and Kuroshio intrusion was not the dominant influencing factor. Further study is needed to discover the comprehensive effect of Kuroshio intrusion on the fate of microplastics and is expected for the whole WBC system.


Assuntos
Microplásticos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Plásticos , Poluentes Químicos da Água/análise
9.
Biochem Biophys Res Commun ; 391(1): 1000-6, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19968957

RESUMO

BACKGROUND AND OBJECTIVE: CypA is able to regulate inflammatory responses and MMPs production via interaction with its cell surface receptor, EMMPRIN. This study aimed to address the possible association of CypA with pathological inflammation and destruction of periodontal tissues, and whether CypA-EMMPRIN interaction exists in periodontitis. MATERIALS AND METHODS: Experimental periodontitis was induced by ligation according to our previous method. Histological and radiographic examinations were performed. Western blot was used to detect CypA and EMMPRIN expressions in gingival tissues. Immunohistochemistry was applied for CypA, EMMPRIN, MMP-1, MMP-2, MMP-9, as well as cell markers of macrophage, lymphocyte and neutrophil. CypA expression, alveolar bone loss, and inflammatory infiltrations were quantified followed by correlation analyses. RESULTS: Western blot revealed that CypA and EMMRPIN expressions were dramatically elevated in inflamed gingival tissues (ligature group) as compared to healthy gingival tissues (control group). The enhanced CypA and EMMPRIN expressions were highly consistent in cell localization on seriate sections. They were permanently co-localized in infiltrating macrophages and lymphocytes, as well as osteoclasts and osteoblasts in interradicular bone, but rarely expressed by infiltrating neutrophils. MMP-1, MMP-2, and MMP-9 expressions were also sharply increased in inflamed gingiva. MMP-2 and MMP-9 were mainly over-expressed by macrophages, while MMP-1 was over-produced by fibroblasts and infiltrating cells. The number of CypA-positive cells was strongly correlated with the ACJ-AC distance (r=0.839, p=0.000), the number of macrophages (r=0.972, p=0.000), and the number of lymphocytes (r=0.951, p=0.000). CONCLUSION: CypA is associated with the inflammatory infiltration and alveolar bone destruction of periodontitis. CypA-EMMPRIN interaction may exist in these pathological processes.


Assuntos
Perda do Osso Alveolar/enzimologia , Basigina/metabolismo , Ciclofilina A/metabolismo , Periodontite/enzimologia , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/patologia , Animais , Modelos Animais de Doenças , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Periodontite/diagnóstico por imagem , Periodontite/patologia , Radiografia , Ratos , Ratos Sprague-Dawley
10.
Wei Sheng Wu Xue Bao ; 50(8): 981-7, 2010 Aug.
Artigo em Zh | MEDLINE | ID: mdl-20931863

RESUMO

Rumen of ruminant animals is known as a natural reactor involved in highly efficient lignocelluloses degradation. Rumen fibrolytic microbes have attracted an increasing attention for their potential value in biofuel research. Studies on rumen microbes have traditionally entailed the isolation of fibrolytic bacteria and subsequent analysis of fibrolytic enzymes. Developments in genomic and metagenomic approaches have made it possible to isolate directly genes and gene clusters encoding fibrolytic activities from rumen samples, permitting a global analysis of mechanisms of degradation of lignocellulose in rumen. Research in this field shows that lignocellulose degradation in rumen is a complex process involving a number of different microbes and is effected by a huge array of hydrolytic enzymes in a concerted fashion. This review briefly summarizes results from recent studies, especially metagenomic studies, on lignocellulose degradation in rumen.


Assuntos
Bactérias/metabolismo , Celulase/genética , Glicosídeo Hidrolases/genética , Lignina/metabolismo , Rúmen/microbiologia , Animais , Bactérias/genética , Biodegradação Ambiental , Cromossomos Artificiais Bacterianos , Biblioteca Gênica , Metagenômica
11.
Prep Biochem Biotechnol ; 39(1): 81-91, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19090423

RESUMO

The present assessments of potential toxicity of metal ions (Al, Ni, Cr, V, and Ag) that construct the metallic biomaterials were carried out in vitro. By measurements of cell alkaline phosphatase (ALP) activity and reduction ability of cell methyl tetrazolium (MTT), the cytotoxicity of prevalence metallic biomaterials has been investigated. Furthermore, the poison and erosion of metal ions and atoms on human tissue are discussed. Research results indicated that trace Cr(VI) showed serious cytotoxicity and Ni as well as V are cytotoxic if the ion concentration in culture medium is over 100 micromol x L(-1) and 1 micromol x L(-1), respectively. A strange phenomenon is that Ag also is cytotoxic if the ion concentration is higher than 500 micromol x L(-1). Al ion is biphasic in cytotoxicity. At low ion concentration (< 10 micromol x L(-1)), Al ions can stimulate cell proliferation, whereas at concentrations over 1,000 micromol x L(-1), cytotoxicity increases.


Assuntos
Materiais Biocompatíveis/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Teste de Materiais/métodos , Metais/toxicidade , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Próteses e Implantes , Testes de Toxicidade/métodos , Animais , Células Cultivadas , Citotoxinas/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Osteoblastos/citologia , Ratos
12.
Talanta ; 198: 128-136, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30876540

RESUMO

In pure water system, the specific and rapid detection of cysteine (Cys) is very important and challenging. Herein, a new optical probe was developed for the purpose based on the complex of cupric ion (Cu2+) with a water-soluble conjugated polymer, poly[3-(3-N,N-diacetateaminopropoxy)-4-methyl thiophene disodium salts] (PTCO2). The fluorescence of PTCO2 in 100% aqueous solution can almost completely extinguished by Cu2+ ions due to its intrinsic paramagnetic properties. Among various amino acids, only Cys causes immediately the efficient recovery of the Cu2+-quenched fluorescence of PTCO2 with ~31-folds fluorescence enhancement because of the stronger affinity of Cys to Cu2+ leading to the formation of Cu2+-Cys complex through Cu-S bond and separation of Cu2+ from weak-fluorescent PTCO2-Cu(II) ensemble and thereby restoring the free PTCO2 fluorescence. In tris-HCl buffer solution (2 mM, pH 7.4), the intensity of the restored fluorescence is linear with the concentration of Cys, ranging from 0 to 120 µM and the estimated detection limit of Cys is 3.3 × 10-7 M with the correlation coefficient R = 0.9981. In addition, the PTCO2-Cu(II) ensemble probe exhibits low cytotoxicity and good membrane penetration, and its application in living cell imaging of Cys has also been explored.


Assuntos
Cobre/química , Cisteína/análise , Corantes Fluorescentes/química , Imagem Óptica , Polímeros/química , Sobrevivência Celular/efeitos dos fármacos , Cobre/farmacologia , Relação Dose-Resposta a Droga , Corantes Fluorescentes/farmacologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Íons/química , Estrutura Molecular , Teoria Quântica , Solubilidade , Relação Estrutura-Atividade , Água/química
13.
J Chromatogr A ; 1479: 137-144, 2017 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-27939601

RESUMO

Covalent-organic frameworks (COFs) are a newfangled class of intriguing microporous materials. Considering their unique properties, COFs should be promising as packing materials for high performance liquid chromatography (HPLC). However, the irregular shape and sub-micrometer size of COFs synthesized via the traditional methods render the main obstacles for the application of COFs in HPLC. Herein, we report the preparation of methacrylate-bonded COF monolithic columns for HPLC to overcome the above obstacles. The prepared COF bonded monolithic columns not only show good homogeneity and permeability, but also give high column efficiency, good resolution and precision for HPLC separation of small molecules including polycyclic aromatic hydrocarbons, phenols, anilines, nonsteroidal anti-inflammatory drugs and benzothiophenes. Compared with the bare polymer monolithic column, the COF bonded monolithic columns show enhanced hydrophobic, π-π and hydrogen bond interactions in reverse phase HPLC. The results reveal the great potential of COF bonded monoliths for HPLC and COFs in separation sciences.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Metacrilatos/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia de Fase Reversa , Interações Hidrofóbicas e Hidrofílicas , Fenóis/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Polímeros/química , Porosidade , Temperatura , Tiofenos/isolamento & purificação
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 118: 765-75, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24144830

RESUMO

The absorption spectra of Cu(2+), Pb(2+), Cd(2+), and Ni(2+) chelates of an amphoteric chelating polymer flocculant (ACPF) were measured by ultraviolet spectrophotometry, and their compositions and stability constants (ß) were calculated. ACPF exhibited three apparent absorption peaks at 204, 251, and 285 nm. The CSS(-) group of ACPF reacted with Cu(2+), Ni(2+), Pb(2+), and Cd(2+) to form ACPF-Cu(2+), ACPF-Ni(2+), ACPF-Pb(2+), and ACPF-Cd(2+) chelates, respectively, according to a molar ratio of 2:1. The maximum absorption peaks of ACPF-Cu(2+), ACPF-Ni(2+), ACPF-Pb(2+), and ACPF-Cd(2+) appeared at 319, 326, 310, and 313.5 nm, respectively. The maximum absorption peaks of the chelates showed significant red shifting compared with the absorption peaks of ACPF. The ß values of the ACPF-Cu(2+), ACPF-Pb(2+), ACPF-Cd(2+), and ACPF-Ni(2+) chelates were (1.37±0.35)×10(12), (3.26±0.39)×10(11), (2.05±0.27)×10(11), and (3.04±0.45)×10(10), respectively. The leaching rate of heavy metal ions from the chelating precipitates decreased with increasing pH. ACPF-Cu(2+), ACPF-Ni(2+), ACPF-Pb(2+), and ACPF-Cd(2+) were very stable at pH≥5.6. Cu(2+), Ni(2+), Pb(2+), and Cd(2+) concentrations in the leaching liquors were lower than the corresponding limits specified by the Integrated Wastewater Discharge Standard of China.


Assuntos
Cádmio/química , Quelantes/química , Cobre/química , Chumbo/química , Níquel/química , Polímeros/química , Floculação , Concentração de Íons de Hidrogênio , Espectrofotometria Ultravioleta
15.
J Biomater Sci Polym Ed ; 21(6-7): 821-42, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20482987

RESUMO

While silicone elastomers generally have excellent biomaterials properties, their hydrophobicity can elicit undesired local biological responses through adsorption and denaturation of proteins. Surface-bound poly(ethylene glycol) (PEG) can ameliorate the situation by preventing contact between the external biology and the silicone elastomer. It is further possible to manipulate the biocompatibility of the surface by linking peptides, proteins or other biological entities to the PEG. Previous synthetic approaches to PEG-protected surfaces are compromised by issues of reproducibility. We describe two rapid and efficient approaches to silicone surface modification by PEG-linked adhesion peptides that overcome this problem: SiH groups are introduced throughout a silicone elastomer during elastomer synthesis or only at the surface after cure; then, in either case, protein-repellent PEG brushes at the surface are introduced by hydrosilylation to give surfaces that can be stored for extensive periods of time without degradation. Activation of the free alcohol with an NSC group followed by immediate conjugation to relevant biological molecules occurs in high yields, as shown for RGDS and GYRGDS. High surface grafting density of the peptides was demonstrated using radiolabeling techniques. Biological activity was demonstrated by a 5-fold increase in cell adhesion on the peptide-modified surfaces when compared to unmodified PDMS control surfaces.


Assuntos
Materiais Biocompatíveis/química , Adesão Celular , Peptídeos/química , Polietilenoglicóis/química , Silicones/química , Materiais Biocompatíveis/metabolismo , Células Cultivadas , Células Endoteliais/citologia , Humanos , Peptídeos/metabolismo , Propriedades de Superfície , Veias Umbilicais/citologia
16.
J Med Eng Technol ; 34(7-8): 455-61, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20925477

RESUMO

The effects of metal ions on the cell DNA and RNA synthetic functions and the destruction of cell defensive system caused by metal ions were studied on the investigation of the effects of metal ions on cell alkaline phosphatase (ALP) activity and cell metabolism ability. The poisonous behaviours of metal ions [Cr (VI), Ni, V, Cr (III), Ag, and Al] on living tissue were both quantitatively and qualitatively measured. It was shown that Cr (VI) has a notable action on both cellular DNA and RNA synthetic functions, and following that, were Ni, V. The limitation action of Cr (III) on the synthetic abilities of DNA and RNA increased with the increase of Cr (III) concentration. Different to other five metal ions, the limitation of Al ion on RNA was greater than that on DNA. The limitation of V, Ag ions on DNA was same to that on RNA. Trace Cr (VI), in culture medium resulted in the decreasing of GSH in living tissue. Similar to that, a little higher Ni ion concentration seriously reduced the GSH content in living tissue. It was suggested that Cr (VI), Ni, might destroy and/or disturb the orientation of the microtubulin in cell skeleton. For other four metal ions, together with increasing the concentration in culture medium, the osmotic pressure increased. Consequently, more metal ions entered cell membrane, more GSH were lost in cell.


Assuntos
Materiais Biocompatíveis/toxicidade , Vias Biossintéticas/efeitos dos fármacos , Metais Pesados/toxicidade , Análise de Variância , Animais , Células Cultivadas , DNA/análise , DNA/metabolismo , Glutationa/análise , Glutationa/metabolismo , Histocitoquímica , Humanos , Teste de Materiais , Microscopia , Pressão Osmótica , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Próteses e Implantes , RNA/análise , RNA/metabolismo , Ratos , Testes de Toxicidade
17.
Macromol Biosci ; 8(3): 260-7, 2008 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-18008299

RESUMO

Biomineralized polysaccharide-coated alginate beads containing PNIPAAM were prepared. The resulting beads can be used as carriers for sustained pH/temperature-sensitive drug delivery. Characterizations using SEM, EDS, FTIR, and POM revealed that the beads were covered by the calcium-phosphate-mineralized alginate/chitosan membrane. The drug-release behavior was examined using indomethacin as a model drug, and the release profile of the developed materials was found to be responsive to pH and temperature. The release profile could be sustained under neutral conditions, indicating that the mineralized polysaccharide membrane could prevent the permeability of the encapsulated drug and reduce the drug release rate.


Assuntos
Resinas Acrílicas/química , Alginatos/química , Sistemas de Liberação de Medicamentos/métodos , Microesferas , Polissacarídeos/química , Preparações de Ação Retardada/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Indometacina/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
18.
Artigo em Inglês | MEDLINE | ID: mdl-18206397

RESUMO

OBJECTIVE: The aim of this report was to examine the oral cancer incidence by sex, race/ethnicity, and anatomical subsite. STUDY DESIGN: Data from the California Cancer Registry (CCR) were used to calculate the age-adjusted incidence rates of invasive oral squamous cell carcinoma (OSCC) by sex, race/ethnicity, and anatomical subsite among residents in California during 1988 to 2001. RESULTS: Although non-Hispanic (NH) black men have the highest overall incidence rate for OSCC, NH whites and NH blacks have similar incidence patterns by subsite, but the male-to-female (M:F) rate ratio is higher among NH blacks. The OSCC incidence rates for Hispanics are much lower than those for NH whites and NH blacks and similar to those of Asians. The Asian ethnic groups display dramatic variations in terms of the subsite-specific incidence rates and M:F rate ratios. CONCLUSION: The findings illustrate the heterogeneity and complexity of oral cancer by anatomical location and the importance of cultural habits and behavioral factors in the development of oral cancer.


Assuntos
Carcinoma de Células Escamosas/etnologia , Neoplasias Bucais/etnologia , Grupos Raciais/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Distribuição por Idade , California/epidemiologia , California/etnologia , Carcinoma de Células Escamosas/epidemiologia , Intervalos de Confiança , Feminino , Neoplasias Gengivais/epidemiologia , Neoplasias Gengivais/etnologia , Humanos , Incidência , Masculino , Soalho Bucal , Neoplasias Bucais/epidemiologia , Neoplasias Palatinas/epidemiologia , Neoplasias Palatinas/etnologia , Grupos Raciais/etnologia , Distribuição por Sexo , Neoplasias da Língua/epidemiologia , Neoplasias da Língua/etnologia
19.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 43(5): 281-5, 2008 May.
Artigo em Zh | MEDLINE | ID: mdl-18953912

RESUMO

OBJECTIVE: To investigate the effect of baicalin on the experimental periodontitis in rats, as well as the expression of MMP-1, MMP-2, MMP-9. METHODS: Twenty-seven adult male Sprague-Dawley rats were divided into three groups, with 9 rats in each group. A nylon thread was placed around the lower first molars of rats, which were sacrificed after 7 days. Baicalin (200 mg/kg) was administered to the experimental group by oral gavage, starting one day before the induction of periodontitis. The negative control group received vehicle (0.5% carboxymethylcellulose) alone. The blank control group did not get induction of periodontitis. The alveolar bone loss (ABL) and the area fraction (AA% ) occupied by collagen fibers were assessed. MMP-1, MMP-2 and MMP-9 protein expressions in the gingiva were detected by immunohistochemistry. RESULTS: Baicalin treatment significantly decreased ABL compared with the negative control group (P = 0.009). AA% of collagen fibers was significantly higher in baicalin-treated group than in the negative control group (P = 0.047). Baicalin treatment significantly down-regulated the protein expression for MMP-1 (P = 0.023) and MMP-9 (P = 0.042) and decreased the expression for MMP-2 (P = 0.099) compared with the negative control group. CONCLUSIONS: Baicalin protects against tissue damage in ligature-induced periodontitis in rats, which might be mediated in part by its inhibitory effect on the expression of MMP-1, MMP-2 and MMP-9.


Assuntos
Flavonoides/farmacologia , Gengiva/efeitos dos fármacos , Gengiva/metabolismo , Periodontite/metabolismo , Animais , Masculino , Metaloproteinases da Matriz/metabolismo , Ratos , Ratos Sprague-Dawley
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