Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Radiology ; 285(2): 462-471, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28631963

RESUMO

Purpose To investigate the role of a tumor-penetrating peptide (internalizing CRGDRGPDC [iRGD])-integrated thermally sensitive liposomal (TSL) doxorubicin (DOX) in combination with radiofrequency (RF) ablation of liver tumors in an animal model. Materials and Methods Approval from the institutional animal care and use committee was obtained. Characterization of iRGD-TSL-DOX was performed in vitro. Next, H22 liver adenocarcinomas were implanted in 138 mice in vivo. The DOX accumulation and cell apoptosis of iRGD-TSL-DOX and TSL-DOX with or without RF were evaluated (n = 5) at different time points after treatment with quantitative analysis or pathologic staining. Mice bearing tumors were randomized into the following six groups (each group, eight mice): no treatment, iRGD-TSL-DOX, TSL-DOX, RF alone, RF ablation followed by TSL-DOX at 30 minutes (TSL-DOX combined with RF), and RF ablation followed by iRGD-TSL-DOX (iRGD-TSL-DOX combined with RF). Kaplan-Meier method was used to estimate the survival curves and log-rank test was used for comparison with statistical software. Results DOX encapsulation efficiency in iRGD-TSL-DOX was 97.5% ± 1.3 (standard deviation) with temperature-dependent drug release capability confirmed in vitro. In vivo, the iRGD-TSL-DOX group had overall higher DOX concentration in the tumor and had maximal difference at 24 hours compared with TSL-DOX group (2.7-fold). RF caused more intense cell apoptosis at 24 hours (median, 65% vs 21%, respectively; P < .001). For end-point survival, the iRGD-TSL-DOX combined with RF group had better survival (median, 32 days) than TSL-DOX combined with RF (median, 27 days; P = .035) or RF alone (median, 21 days; P < .001). Conclusion Conjugation to iRGD helped to improve intratumoral DOX accumulation and further enhanced the activity of TSL-DOX in RF ablation of liver tumors. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Antineoplásicos/farmacocinética , Ablação por Cateter/métodos , Doxorrubicina/análogos & derivados , Neoplasias Hepáticas Experimentais/terapia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Terapia Combinada , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Temperatura Alta , Camundongos , Peptídeos/química , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Biosens Bioelectron ; 254: 116221, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38513541

RESUMO

Antibiotics are widely used for treating bacterial infections. However, excessive or improper use of antibiotics can pose a serious threat to human health and water environments, and thus, developing cost-effective, portable and effective strategies to analyze and detect antibiotics is highly desired. Herein, we reported a responsive photonic hydrogel (RPH)-based optical biosensor (PPNAH) with superior recyclability for sensitive and colorimetric determination of a typical ß-lactam antibiotic penicillin G (PG) in water. This sensor was composed of poly(N-isopropylacrylamide-co-acrylamide) smart hydrogel with incorporated penicillinase and Fe3O4@SiO2 colloidal photonic crystals (CPCs). The sensor could translate PG concentration signals into changes in the diffraction wavelength and structural color of the hydrogel. It possessed high sensitivity and selectivity to PG and excellent detection performances for other two typical ß-lactam antibiotics. Most importantly, due to the unique thermosensitivity of the poly(N-isopropylacrylamide) moieties in the hydrogel, the PG-responded PPNAH sensor could be facilely regenerated via a simple physical method at least fifty times while without compromising its response performance. Besides, our sensor was suitable for monitoring the PG-contaminated environmental water and displayed satisfactory detection performances. Such a sensor possessed obvious advantages of superior recyclability, highly chemical stability, low production cost, easy fabrication, wide range of visual detection, simple and intuitive operation for PG detection, and environmental-friendliness, which holds great potential in sensitive and colorimetric detection of the PG residues in polluted water.


Assuntos
Acrilamidas , Resinas Acrílicas , Técnicas Biossensoriais , Hidrogéis , Humanos , Hidrogéis/química , Penicilinase , Acrilamida , Colorimetria , Dióxido de Silício , Técnicas Biossensoriais/métodos , Penicilina G , Antibacterianos/análise , Água
3.
Anal Chem ; 85(13): 6477-84, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23687902

RESUMO

A novel, simple, portable, and low-cost method for diagnosis of hyperkalemia by using K(+)-recognizable poly(N-isopropylacrylamide-co-benzo-15-crown-5-acrylamide) [poly(NIPAM-co-B15C5Am)] linear copolymer as indicator is presented in this work. The pendent 15-crown-5 units in the linear copolymers can selectively and specifically recognize K(+) to form stable 2:1 "sandwich" host-guest complexes, which cause the copolymer chains to change from the hydrophilic state to the hydrophobic state isothermally, whereas other tested metal ions (e.g., Li(+), Na(+), Cs(+), Mg(2+), Ca(2+), Sr(2+), Ba(2+), Cu(2+), Fe(3+), Pb(2+), Cd(2+), Cr(3+)) cannot be recognized. With increasing the 15-crown-5 content or the K(+) concentration, the poly(NIPAM-co-B15C5Am) linear copolymers exhibit higher sensitivity to K(+). The hyperkalemia can be simply diagnosed by observing the K(+)-induced optical transmittance change of human blood samples with poly(NIPAM-co-B15C5Am) linear copolymer as an indicator. Normal blood samples with low potassium level containing the poly(NIPAM-co-B15C5Am) linear copolymer are almost transparent since the copolymer is hydrophilic and soluble at the operating temperature. However, severe hyperkalemia samples with high potassium level become completely cloudy since the copolymer is hydrophobic and insoluble at this temperature. The presented diagnosis method with poly(NIPAM-co-B15C5Am) linear copolymer as indicator is quite simple and low-cost, and it would bring a new candidate material to design simple and portable tools for diagnosis of hyperkalemia in the general population. Moreover, the results in this work provide valuable guidance for building novel poly(NIPAM-co-B15C5Am)-based artificial K(+)-recognizable "smart" or "intelligent" systems in various application fields.


Assuntos
Resinas Acrílicas/química , Técnicas Biossensoriais/métodos , Hiperpotassemia/sangue , Hiperpotassemia/diagnóstico , Potássio/química , Técnicas Biossensoriais/instrumentação , Humanos
4.
Appl Biochem Biotechnol ; 195(11): 6537-6556, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36877441

RESUMO

The efficient and economical removal of fermentation inhibitors from the complex system of biomass hydrolysate was one of the basics and keys in bio-chemical transformation. In this work, post-cross-linked hydrophilic-hydrophobic interpenetrating polymer networks (PMA/PS_pc IPNs and PAM/PS_pc IPNs) were proposed to remove fermentation inhibitors from sugarcane bagasse hydrolysate for the first time. PMA/PS_pc and PAM/PS_pc IPNs can obviously enhance the adsorption performance towards fermentation inhibitors due to their higher surface area and hydrophilic-hydrophobic synergetic surface properties, especially PMA/PS_pc IPNs has higher selectivity coefficients of 4.57, 4.63, 4.85, 16.0, 49.43, and 22.69, and higher adsorption capacity of 24.7 mg/g, 39.2 mg/g, 52.4 mg/g, 9.1 mg/g, 13.2 mg/g, and 144.9 mg/g towards formic acid, acetic acid, levulinic acid (LA), 5-hydroxymethylfurfural (HMF), furfural, and acid-soluble lignin (ASL), respectively, in a lower total sugar loss of 2.03%. The adsorption kinetics and isotherm of PMA/PS_pc IPNs were studied to elucidate its adsorption behavior towards fermentation inhibitors. In addition, the cyclic utilization property of PMA/PS_pc IPNs was stable. Synthesizing PMA/PS_pc IPNs is a new strategy to provide an efficient adsorbent for the removal of fermentation inhibitors from lignocellulosic hydrolysate.


Assuntos
Celulose , Saccharum , Celulose/metabolismo , Polímeros , Fermentação , Saccharum/química , Hidrólise
5.
J Chromatogr A ; 1682: 463505, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36152484

RESUMO

A novel nano petal-shaped covalent organic frameworks modified magnetic polystyrene-divinylbenzene-glycidylmethacrylate (NP-COF@Mag-PS/DVB/GMA) microsphere has been synthesized. It is a perfect combination of high productivity of PS/DVB/GMA microspheres and excellent enrichment efficiency of COF particles, and the excellent properties of NP-COF@Mag-PS/DVB/GMA microspheres are characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and X-ray photoelectron spectroscopy (XPS). The sorbent can extract illicit drugs via the reverse-phase interactions provided by benzene ring on the polymer backbone and the hydrogen bonding interactions provided by functional group (-NH-) on the COF particles. Based on using NP-COF@Mag-PS/DVB/GMA as sorbents, an easiness-to-handle of magnetic dispersive solid phase extraction (Mag-dSPE) procedure is proposed for the simultaneous preconcentration of 12 illicit drugs from wastewater. The obtained results show high extraction efficiency of NP-COF@Mag-PS/DVB/GMA to illicit drugs with recoveries between 81.6 and 116%. Furthermore, a liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) method for the determination of 12 illicit drugs from wastewater at sub-ppt levels has been proposed and validated with the pretreatment of samples by Mag-dSPE. The limits of quantification (LOQs) for the 12 illicit drugs are between 0.40 and 4.90 ng/L. Validation results on linearity, specificity, trueness and precision, as well as on application to the analysis of 12 illicit drugs in ten real samples demonstrate the applicability to environment monitoring analysis.


Assuntos
Drogas Ilícitas , Estruturas Metalorgânicas , Benzeno , Cromatografia Líquida , Estruturas Metalorgânicas/química , Microesferas , Poliestirenos/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem , Compostos de Vinila , Águas Residuárias/química
6.
Cancer Chemother Pharmacol ; 89(2): 209-215, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35022817

RESUMO

PURPOSE: The repeated use of doxorubicin is limited due to dose-limiting cardiac toxicity. Pegylated liposomal doxorubicin (PEG-LD, Duomeisu) has a reduced cardiac toxicity. This phase I study aimed to investigate the maximum tolerated doses (MTDs) and dose-limiting toxicities (DLTs) of the PEG-LD and cisplatin combination in patients with metastatic and recurrent osteosarcoma. METHODS: Patients were given PEG-LD at a dose of 40, 50, or 60 mg/m2 on day 1 of each 21-day cycle, according to a 3 + 3 approach for dose escalation. Cisplatin was administered as a fixed dose of 100 mg/m2 for every cycle. Toxicities and tumor response were observed. RESULTS: A total of 15 patients were enrolled in this trial, and nine of the patients had received prior doxorubicin. The MTD of PEG-LD was reached at 50 mg/m2 in this regimen, with neutropenic fever and stomatitis as DTLs. The main adverse event (AE) was myelosuppression. The most common non-hematological AEs were vomiting, hypoproteinemia, stomatitis and transient sinus arrhythmia. Grade 3-4 toxicity was neutropenia, leukopenia, thrombocytopenia, anemia and stomatitis in the whole cohort. All the AEs were relieved after symptomatic and supportive treatment. Totally, the overall response rate was 13.3% and disease control rate was 66.7%. For the six patients who have not received prior doxorubicin, one partial response and five stable diseases were observed. CONCLUSION: We provide the data showing that PEG-LD 50 mg/m2 combined with cisplatin 100 mg/m2 demonstrated an acceptable safety profile and promising clinical activity in advanced osteosarcoma, which merits further evaluation in phase II studies. TRIAL REGISTRATION: ChiCTR1900021550.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Ósseas/patologia , Cisplatino/administração & dosagem , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Osteossarcoma/patologia , Polietilenoglicóis/administração & dosagem , Resultado do Tratamento , Adulto Jovem
7.
Zhonghua Zhong Liu Za Zhi ; 33(3): 229-31, 2011 Mar.
Artigo em Zh | MEDLINE | ID: mdl-21575526

RESUMO

OBJECTIVE: To evaluate the efficacy and toxicity of paclitaxel with low-dose cisplatin and 5-fluorouracil continuous infusion in the treatment of advanced gastric carcinoma. METHODS: The patients were treated with paclitaxel liposome 60 mg/m(2) i.v. gtt on d1, 8, 15, DDP 15 mg×m(-2)×d(-1) by i.v. gtt on d1-5, 5-Fu 500 mg×m(-2)×d(-1) by civ for 120 h, administered every 21 days. RESULTS: Out of the whole group, 3 cases achieved CR, 29 cases achieved PR with an ORR of 54.2% and median TTP of 7.1 months. Out of 40 cases in the primary treatment, 3 cases achieved CR, 22 cases achieved PR with an ORR of 62.5% and median TTP of 7.6 months. Out of 20 evaluable retreated cases, no case achieved CR, 7 cases achieved PR with an ORR of 36.8% and median TTP 6.3 months. The main toxicities were hematological toxicities, nausea and vomiting of grade I-II. CONCLUSION: The combination regimen of paclitaxel, low-dose cisplatin and 5-fluorouracil is effective and well tolerated for patients with advanced gastric carcinoma, especially for primary treatment cases. It is worthy of further study.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Infusões Intravenosas , Leucopenia/induzido quimicamente , Lipossomos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Indução de Remissão , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Vômito/induzido quimicamente , Adulto Jovem
8.
Sci Total Environ ; 767: 144345, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33434834

RESUMO

PURPOSE: Microplastics have been widely detected in the environment and marine organisms. However, few studies have investigated the presence of microplastics in humans. This preliminary study identified and quantified the microplastic content in human feces. METHODS: A total of 26 young male students aged 18-25 years were recruited from Beijing, China. A self-administered 7-day 24-h fluid intake record was used to document fluid intake, and food intake was recorded for 3 days. Feces were collected by participants using a sterile fecal collector. Microplastics in the remaining fecal residues were measured and identified using fourier transform infrared micro-spectroscopy. RESULTS: Eventually, twenty-four participants completed the study. The fecal samples of 23 (95.8%) participants tested positive for microplastics. In these 23 samples, the abundance of microplastics varied from 1 particle/g to 36 particles/g (size 20 to 800 µm). The summed mass of all microplastic particles per participant ranged from 0.01 to 14.6 mg. Qualitative analysis of the microplastics indicated the presence of one to eight types of microplastics in each sample, with polypropylene (PP) being the most abundant; it was found in 95.8% of fecal samples. We examined associations between water intake habits and the abundance of microplastics in their feces. A moderate correlation was observed between packaged water and beverage intake and microplastic abundance in feces (r = 0.445, P = 0.029). CONCLUSION: Various types of microplastics were detected in human feces, with PP being found in the highest proportion. There may be an association between water intake habits and microplastic abundance in feces.


Assuntos
Microplásticos , Poluentes Químicos da Água , Adolescente , Adulto , Pequim , China , Monitoramento Ambiental , Fezes/química , Humanos , Masculino , Plásticos , Poluentes Químicos da Água/análise , Adulto Jovem
9.
Int J Pharm ; 580: 119123, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32035258

RESUMO

The development of small molecule anticancer drugs, with low water solubility and high toxicity, into polymeric prodrugs has developed into a promising strategy in clinical application. In this study, we synthesized a novel G3-C12-mediated esterase-sensitive tumor-targeting polymeric prodrug of camptothecin (CPT), P(OEGMA-co-CPT-co-G3-C12), and explored its anticancer activity against androgen-independent prostate cancer in vitro and in vivo. Compared to free CPT, the multifunctional polymeric prodrug demonstrated improved water solubility and stability, higher intracellular uptake, and enhanced cytotoxicity in DU145 cells in vitro. Furthermore, it displayed an improved accumulation in the tumor and an enhanced anticancer activity in vivo. Hence, P(OEGMA-co-CPT-co-G3-C12) could be a promising drug in the treatment of androgen-independent prostate cancer.


Assuntos
Proteínas Sanguíneas/metabolismo , Camptotecina/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Desenvolvimento de Medicamentos/métodos , Galectinas/metabolismo , Pró-Fármacos/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo , Animais , Camptotecina/administração & dosagem , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Polímeros/administração & dosagem , Polímeros/metabolismo , Pró-Fármacos/administração & dosagem , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
10.
Bioresour Technol ; 318: 124053, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32942092

RESUMO

Economical removal of fermentation inhibitors from lignocellulosic hydrolysate plays a considerable role in bioconversion of lignocellulose biomass. In this work, the textural properties of polyacrylamide/polystyrene interpenetrating polymer networks (PAM/PS IPNs) on adsorption of fermentation inhibitors from sugarcane bagasse hydrolysate (SCBH) were investigated for the first time. The results showed that, the specific surface area, pore diameter and surface polarity had important influence on its adsorption performance towards sugars, organic acids, furans and acid-soluble lignin. The PAM/PS IPNs under the optimal copolymerization situation achieved the high selectivity coefficients of 4.07, 14.9, 21.2 and 25.8 with respective to levulinic acid, furfural, hydroxymethylfurfural (HMF) and acid-soluble lignin, and had a low total sugar loss of 2.09%. Overall, this research puts forward a design and synthetic strategy for adsorbent to remove fermentation inhibitors from lignocellulosic hydrolysate.


Assuntos
Saccharum , Resinas Acrílicas , Adsorção , Celulose , Fermentação , Hidrólise , Lignina/metabolismo , Polímeros , Poliestirenos , Saccharum/metabolismo
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(2): 609-616, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32319404

RESUMO

OBJECTIVE: To investigate the effects of polyvinyl alcohol (PVA) + graphene oxide (GO, weight content 1 wt%) aerogel three-dimensional (3D) scaffolds culture system on the proliferation, phenotype and drug resistance of ALL cell line Jurkat and AML cell line HL-60. METHODS: Jurkat cells and HL-60 cells were seeded in PVA+GO aerogel scaffolds for culture, and the structure of cells were observed by the scanning electron microscopy. Cell proliferation activity was measured by Cell Counting Kit-8 (CCK-8), cell phenotypes were analyzed by flow cytometry after fluorescent staining, then were compared with 2D cultured cells. Ara-C was used in drug resistance experiment, and CCK8 was used to detected cell proliferation activity. RESULTS: The proliferation activity of Jurkat cells grown in aerogel scaffolds was higher than that by 2D cultured in long-term culture. However, in HL-60 cells, the proliferation activity on 3D scaffold only at the 8th to 20th day was higher than that on the traditional 2D culture. Expression of CD4 in Jurkat cells increased after culture for 30 days, but the cell phenotypes in the 3D aerogel scaffolds were similar to 2D cultured cells. Phenotype of HL-60 cells was certainly changed after culture for 30 days, the cells can be divided into CD13+CD14-CD45+HLA-DR+,CD13-CD14--CD45+HLA-DR+ and CD13-CD14-CD45+HLA-DR- groups, and a new CD13+CD14-CD45-HLA-DR+ group of cells appeared in the cells cultured in 3D scaffolds, but not in 2D cultured cells. Drug resistance experiments showed that Jurkat cells in aerogel scaffolds have stronger drug resistance than those in 2D culture. CONCLUSION: PVA+GO (1 wt%) aerogel scaffolds can improve the proliferation and drug resistance of leukemia cells, and the phenotypes were the same as those in 2D culture, which can be used for cell amplification and biology characteristics studies and drug experiments. However, cell phenotypes should be analyzed before culture, and the effects of phenotypes changes on drug resistance should be eliminated.


Assuntos
Leucemia Mieloide Aguda , Linhagem Celular , Proliferação de Células , Grafite , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Álcool de Polivinil , Alicerces Teciduais
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(4): 1100-3, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19626911

RESUMO

In brick-tea fluorosis affected areas XiLinHot city in Inner Mongolia, herdsmen who like drinking a large amount of brick tea in everyday life and Han habitants rarely drinking brick tea as control group were enrolled, and their hair and urine were sampled. The concentrations of Ca, Mg, K, Al, P, Cu, Zn and Fe in hair and urine were detected using ICP-OES. The RSDs of the method were between 2.32% and 8.03%, and the analytical results of the hair reference samples were consistent with the certified values. The results showed that the contents of Al, Mg and K in hair, and contents of Al and Ca in urine of herdsmen who were accustomed to drinking brick tea were obviously higher than those in control group (P<0.05), while the contents of K in urine of herdsmen who were accustomed to drinking brick tea was lower than those in control group (P<0.05), and other elements did not have statistic significance (P>0.05). Chronically drinking brick tea probably brings metabolic disorder of Ca and Al in human body, and the interaction mechanism of life elements in brick-tea fluorosis should be further studied.


Assuntos
Fluorose Dentária/diagnóstico , Cabelo/química , Espectrofotometria Atômica/métodos , Chá/efeitos adversos , Oligoelementos/análise , Urina/química , Alumínio/efeitos adversos , Alumínio/análise , China , Fluoretos/efeitos adversos , Humanos , Oligoelementos/urina
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(2): 329-31, 2007 Feb.
Artigo em Zh | MEDLINE | ID: mdl-17514968

RESUMO

In polyethylene glycol 2000 (PEG)-(NH4)2SO4-edible pigment two-phase aqueous systems, the spectroscopic behaviour of the complexes of edible pigment and human serum albumin in PEG phase was investigated. Effects of different acidity, quantities of PEG and salt, reaction time, and coexistent matter on the determination of systems were discussed. Experimental results show that compared to BS spectra, the maximum wavelength of the complex of human serum albumin shifted to the red by 13 nm in buffer solution at pH 8, the maximum binding number of 40 was measured by molar ratio method, and the apparent molar absorptivity was 9.4 x 10(4) L x mol(-1) x cm(-1). The linear range was 0-21.07 mg x L(-1). With different surfactant, the interaction mechanism of protein and edible pigment was discussed.


Assuntos
Corantes de Alimentos/análise , Polietilenoglicóis/química , Albumina Sérica/análise , Corantes de Alimentos/química , Humanos , Concentração de Íons de Hidrogênio , Albumina Sérica/química , Tensoativos/química
14.
Virol J ; 3: 84, 2006 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-17022821

RESUMO

BACKGROUND: Human cytomegalovirus (HCMV) infection in the oral cavity plays an important role in its horizontal transmission and in causing viral-associated oral diseases such as gingivitis. However, little is currently known about HCMV pathogenesis in oral mucosa, partially because HCMV infection is primarily limited to human cells and few cultured tissue or animal models are available for studying HCMV infection. RESULTS: In this report, we studied the infection of HCMV in a cultured gingival tissue model (EpiGingival, MatTek Co.) and investigated whether the cultured tissue can be used to study HCMV infection in the oral mucosa. HCMV replicated in tissues that were infected through the apical surface, achieving a titer of at least 300-fold at 10 days postinfection. Moreover, the virus spread from the apical surface to the basal region and reduced the thickness of the stratum coreum at the apical region. Viral proteins IE1, UL44, and UL99 were expressed in infected tissues, a characteristic of HCMV lytic replication in vivo. Studies of a collection of eight viral mutants provide the first direct evidence that a mutant with a deletion of open reading frame US18 is deficient in growth in the tissues, suggesting that HCMV encodes specific determinants for its infection in oral mucosa. Treatment by ganciclovir abolished viral growth in the infected tissues. CONCLUSION: These results suggest that the cultured gingival mucosa can be used as a tissue model for studying HCMV infection and for screening antivirals to block viral replication and transmission in the oral cavity.


Assuntos
Citomegalovirus/fisiologia , Gengiva/virologia , Adulto , Idoso , Antivirais/farmacologia , Células Cultivadas , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/genética , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/virologia , Feminino , Fibroblastos , Ganciclovir/farmacologia , Gengiva/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/virologia , Mutação/genética , Técnicas de Cultura de Tecidos , Replicação Viral/efeitos dos fármacos
15.
Yao Xue Xue Bao ; 40(11): 982-7, 2005 Nov.
Artigo em Zh | MEDLINE | ID: mdl-16499080

RESUMO

AIM: To prepare self-microemulsifying drug delivery system (SMEDDS) containing atorvastatin,and decrease its size to improve the solubility in the stomach. And to study the effect of the resultant microemulsion in reducing the presystemic clearance in the gastrointestinal mucosa and hepatic first-pass metabolism, improving the oral bioavailability, and reducing side effect and expenditure. METHODS: Pseudoternary phase diagrams were used to evaluate the self-microemulsification existence area. The HPLC analyses in vitro and in vivo were set up. Solubility in various vehicles was determined. The self-microemulsification efficiency was assessed, such as self-microemulsification time, stability, particle size and zeta potential. SMEDDS containing atorvastatin, non-ionic surfactant and lipid were prepared. Droplet size/distributions and zeta potential of the resultant microemulsion were determined. Photos were taken with transmission electron microscope. Oral bioavailability was studied on prepared SMEDDS hard capsules and compared with that of the conventional tablet in Beagle dogs in vivo. RESULTS: The optimal formulations had wide microemulsion existent field and had good self-microemulsifying efficiency. Droplet size was within 100 nm and showed Gaussian distribution. After oral administration of SMEDDS capsules and the conventional tablet to fasted Beagle dogs, the Cmax from SMEDDS was greater than that of the conventional tablet. AUC from zero to 24 h of SMEDDS was about 1.5-fold higher than that of the conventional tablet. Oral bioavailability of atorvastatin SMEDDS was greater than that of the conventional tablet. CONCLUSION: The results indicated the potential use of SMEDDS for the delivery of atorvastatin to increase its oral bioavailability.


Assuntos
Sistemas de Liberação de Medicamentos , Ácidos Heptanoicos/farmacocinética , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacocinética , Polietilenoglicóis/química , Pirróis/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Atorvastatina , Disponibilidade Biológica , Cães , Emulsões , Glicerol/análogos & derivados , Glicerol/química , Ácidos Heptanoicos/administração & dosagem , Ácidos Heptanoicos/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/sangue , Masculino , Tamanho da Partícula , Pirróis/administração & dosagem , Pirróis/sangue , Solubilidade
16.
Appl Biochem Biotechnol ; 175(3): 1678-88, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25422061

RESUMO

In this study, corncob acid hydrolysate was used as a substrate for bacterial cellulose (BC) production by Gluconacetobacter xylinus. After 2 weeks' static fermentation, a BC yield of 4 g/L could be obtained. Both effects of medium composition and fermentation condition on the BC production were evaluated. Most extra substrates (carbon and nitrogen sources) except mannitol, butyric acid, and levulinic acid showed no effect on the improvement of BC yield. Fermentation condition including fermentation mode, inoculation concentration, and initial pH showed certain influence on the BC yield and thus should be well controlled. The analysis by field emission scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) showed that the BC sample had obvious nano-network structure, clear functional groups that were found in cellulose, and relatively high crystallinity and crystallinity index value. Moreover, the BC sample had great water-holding capacity. Overall, corncob acid hydrolysate could be one promising substrate for BC production.


Assuntos
Ácidos/farmacologia , Celulose/biossíntese , Gluconacetobacter xylinus/metabolismo , Zea mays/química , Celulose/ultraestrutura , Meios de Cultura/farmacologia , Fermentação/efeitos dos fármacos , Gluconacetobacter xylinus/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Hidrólise , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Água , Difração de Raios X , Zea mays/efeitos dos fármacos
17.
ACS Appl Mater Interfaces ; 6(21): 19405-15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25325533

RESUMO

A novel type of smart microspheres with K(+)-induced shrinking and aggregating properties is designed and developed on the basis of a K(+)-recognition host-guest system. The microspheres are composed of cross-linked poly(N-isopropylacrylamide-co-acryloylamidobenzo-15-crown-5) (P(NIPAM-co-AAB15C5)) networks. Due to the formation of stable 2:1 "sandwich-type" host-guest complexes between 15-crown-5 units and K(+) ions, the P(NIPAM-co-AAB15C5) microspheres significantly exhibit isothermally and synchronously K(+)-induced shrinking and aggregating properties at a low K(+) concentration, while other cations (e.g., Na(+), H(+), NH4(+), Mg(2+), or Ca(2+)) cannot trigger such response behaviors. Effects of chemical compositions of microspheres on the K(+)-induced shrinking and aggregating behaviors are investigated systematically. The K(+)-induced aggregating sensitivity of the P(NIPAM-co-AAB15C5) microspheres can be enhanced by increasing the content of crown ether units in the polymeric networks; however, it is nearly not influenced by varying the monomer and cross-linker concentrations in the microsphere preparation. State diagrams of the dispersed-to-aggregated transformation of P(NIPAM-co-AAB15C5) microspheres in aqueous solutions as a function of temperature and K(+) concentration are constructed, which provide valuable information for tuning the dispersed/aggregated states of microspheres by varying environmental K(+) concentration and temperature. The microspheres with synchronously K(+)-induced shrinking and aggregating properties proposed in this study provide a brand-new model for designing novel targeted drug delivery systems.


Assuntos
Éteres de Coroa/química , Microesferas , Potássio/química , Resinas Acrílicas/química , Sistemas de Liberação de Medicamentos/métodos , Tamanho da Partícula , Temperatura
18.
PLoS One ; 8(11): e79194, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24223176

RESUMO

The global population remains vulnerable in the face of the next pandemic influenza virus outbreak, and reformulated vaccinations are administered annually to manage seasonal epidemics. Therefore, development of a new generation of vaccines is needed to generate broad and persistent immunity to influenza viruses. Here, we describe three adjuvants that enhance the induction of stalk-directed antibodies against heterologous and heterosubtypic influenza viruses when administered with chimeric HA proteins. Addavax, an MF59-like nanoemulsion, poly(I:C), and an RNA hairpin derived from Sendai virus (SeV) Cantell were efficacious intramuscularly. The SeV RNA and poly(I:C) also proved to be effective respiratory mucosal adjuvants. Although the quantity and quality of antibodies induced by the adjuvants varied, immunized mice demonstrated comparable levels of protection against challenge with influenza A viruses on the basis of HA stalk reactivity. Finally, we present that intranasally, but not intramuscularly, administered chimeric HA proteins induce mucosal IgA antibodies directed at the HA stalk.


Assuntos
Anticorpos Antivirais/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Imunização/métodos , Vacinas contra Influenza/imunologia , Adjuvantes Imunológicos/administração & dosagem , Administração Intranasal , Animais , Anticorpos Antivirais/sangue , Cães , Emulsões/administração & dosagem , Ensaio de Imunoadsorção Enzimática , Feminino , Células HEK293 , Glicoproteínas de Hemaglutininação de Vírus da Influenza/administração & dosagem , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza A/imunologia , Vacinas contra Influenza/administração & dosagem , Injeções Intramusculares , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Conformação de Ácido Nucleico , Infecções por Orthomyxoviridae/sangue , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Poli I-C/administração & dosagem , Poli I-C/imunologia , Polissorbatos/administração & dosagem , RNA Viral/administração & dosagem , RNA Viral/química , RNA Viral/imunologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/imunologia , Vírus Sendai/genética , Vírus Sendai/imunologia , Esqualeno/administração & dosagem , Esqualeno/imunologia
19.
Shanghai Kou Qiang Yi Xue ; 16(4): 385-7, 2007 Aug.
Artigo em Zh | MEDLINE | ID: mdl-17924023

RESUMO

PURPOSE: To assess the efficacy of intraoral open reduction of mandibular body fracture using titanium miniplate rigid fixation and intermaxillary traction titanium screw to rigidly tract the jaw during the operation. METHODS: 54 mandibular fractures in 45 patients were included in this study. After general anaesthesia, the intermaxillary traction titanium screw was inserted in the alveolar bone, between the two incisors, between the canine and the first premolar, between the first molar and the second molar, and the intermaxillary traction was finished with 0.5 mm stainless steel wire. After the mandibular arch and occlusion relationship were returned to preoperative condition, transoral mucoperiosteal incision was made to expose the fracture lines and fragments. Two 2.0 mm titanium miniplates were adapted along the Champy's line of ideal osteosynthesis and secured. After operation the stainless steel wire was released. Panoramic radiograph and clinical examination were applied at the first day and three months after operation to exhibit bone union and occlusion. RESULTS: Most patients displayed satisfied occlusion and bone union without major complications. Seventeen patients had numbness of the lower lips after operation, and the symptom was disappeared three months later. Two patients had improvement of numbness of the lower lips. CONCLUSION: Intraoral open reduction of mandibular body fracture using titanium miniplate rigid fixation and intermaxillary traction titanium screw showed high efficiency in fixation of the mandibular arch fractures , which occurred in the body and the angle of the mandible.


Assuntos
Fixação Interna de Fraturas , Fraturas Mandibulares/cirurgia , Placas Ósseas , Parafusos Ósseos , Oclusão Dentária , Humanos , Técnicas de Fixação da Arcada Osseodentária , Titânio
20.
Shanghai Kou Qiang Yi Xue ; 16(3): 311-4, 2007 Jun.
Artigo em Zh | MEDLINE | ID: mdl-17660922

RESUMO

PURPOSE: The purpose of this study was to evaluate and compare the friction and abrasion of six kinds of dental materials that was widely used clinically. The mechanisms were investigated to provide experimental reference for selecting proper restorative material to protect opposite natural enamel of the patients. METHODS: In the experimental groups,pure Ti, Ti alloy, Au-Pd alloy, Ni-Cr alloy, AgHg alloy,ceramic were fabricated into thirty uniform 8.0mmx8.0mmx2.0mm block. Five specimens in each group.In the control group,five recently extracted mandibular third molar of adults were fabricated into 8.0mmx8.0mmx2.0mm block. Steatites were fabricated into discs in the diameter of 25mm and thickness of 2.0mm to act as counter sample materials. The mass loss of each specimen and the opposing steatite were weighted by electric balance. The volume loss of the materials and opposing steatites were analyzed by SPSS11.5 software package and the difference was compared between each group. RESULTS: The ranking of the volume loss of six materials and enamel from the most to the least was group A, group E, group C, group D, group B, group F and group G. Significant difference was found between group A and the other groups. No significance was found between group G and F. The coefficient of friction of group A-G was 0.68, 0.12, 0.11, 0.41, 0.38, 0.48 and 0.65,respectively. CONCLUSION: The six materials in this study were less resistant to wear than natural tooth. The wear of pure Ti, AgHg alloy and Ni-Cr alloy are to enamel.


Assuntos
Materiais Dentários , Desgaste de Restauração Dentária , Esmalte Dentário , Porcelana Dentária , Fricção , Teste de Materiais , Propriedades de Superfície
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA