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1.
Aesthetic Plast Surg ; 46(5): 2480-2487, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34993595

RESUMO

BACKGROUND: Botulinum toxin-A (BTX-A) injection of regional platysma has been utilized in the lower-part elevation and mandibular contour sculpture. However, the relative research, especially in quantitative assessment appears very spare. Our aim is to investigate the efficacy of three-dimensional (3D) technology as a method for regional platysma injection with BTX-A. MATERIALS AND METHODS: From October 2019 to September 2020, patients with mild or moderate degrees of facial sagging on the lower face were recruited to regional platysma BTX-A injection, and 3D scanning and measurement technology was used to evaluate the difference of curved distances and angels. Patients' improvement was assessed by the global aesthetic improvement scale (GAIS). RESULTS: A total of 57 patients underwent regional platysma BTX-A injection and 32 patients were followed up successfully. Compared with Pre-operative, postoperative facial reference curves distance and cervico-mental angles had statistical differences (p < 0.05). GAIS suggested that the 3D imaging measurement technology could improve satisfaction. CONCLUSION: 3D technology can evaluate the improvement of the lower face with BTX-A. It provides effective measurement methods and raises satisfaction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Toxinas Botulínicas Tipo A , Sistema Musculoaponeurótico Superficial , Humanos , Seguimentos , Resultado do Tratamento , Tecnologia
2.
Anal Chem ; 92(2): 1940-1947, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31887020

RESUMO

In view of the size and hydrophilicity of glycopeptides, materials having suitable channels (size-exclusion) and strong hydrophilic surface (hydrophilic interaction) are preferred to enrich the glycopeptides in biological samples. Metal-organic frameworks (MOFs) are good candidates. However, their smaller microporous channels and low chemical stability have limited the application. Herein, a facile strategy was established to construct hydrophilic mesoporous MOF via synergistic etching and surface functionalization by using phytic acid (PA). Besides, polyvinylpyrrolidone (PVP) was added during MOF synthesis to enhance the water stability of the MOF. Owing to the expanded hydrophilic mesoporous channels, the PA-modified Ce-MOF effectively and selectively captured 422 glycopeptides from 155 glycoproteins in tryptic digests of human serum (2 µL). The present work sheds light on the easy fabrication of hydrophilic mesoporous materials, and this established material holds unique advantages for glycopeptides analysis in biological samples.


Assuntos
Glicopeptídeos/sangue , Estruturas Metalorgânicas/química , Cromatografia Líquida , Glicoproteínas/sangue , Glicoproteínas/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estruturas Metalorgânicas/síntese química , Ácido Fítico/química , Porosidade , Povidona/química , Proteólise , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tripsina/química
3.
Mikrochim Acta ; 186(9): 600, 2019 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-31377859

RESUMO

A hydrophilic interaction liquid chromatography (HILIC) material with application in glycoproteomics was obtained by sequential deposition of polyethyleneimine (PEI) and hyaluronic acid (HA) on a negatively charged substrate by means of electrostatic self-assembly. This kind of surface modification endows the material with excellent hydrophilicity and warrants efficient glycopeptides enrichment. The feasibility of this enrichment was verified by using dendritic mesoporous silica nanoparticles (DMSNs) and magnetic graphene oxide (MagG) as negatively charged substrates for PEI and HA adhesion. The two final products (DMSNs@PEI@HA and MagG@PEI@HA) exhibit high enrichment selectivity (molar ratios of IgG and BSA digests = 1:500 and 1:1000), sensitivity (detection limit, 2 fmol/µL), recovery (>90%) and enrichment capacity (300 mg/g). When using DMSNs@PEI@HA, 419 N-glycopeptides derived from 105 glycoproteins were identified. When using MagG@PEI@HA, 376 N-glycopeptides derived from 102 glycoproteins were identified, both from a 2 µL serum sample. This is better than by methods described in previous reports. Graphical abstract Schematic representation of hydrophilic modification of negatively charged nanomaterial substrates by electrostatic self-assembly techniques to obtain hydrophilic interaction liquid chromatography (HILIC) materials for enrichment of N-glycopeptides.


Assuntos
Glicopeptídeos/análise , Ácido Hialurônico/química , Polietilenoimina/química , Eletricidade Estática , Cromatografia Líquida , Grafite/química , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Nanopartículas/química , Tamanho da Partícula , Porosidade , Dióxido de Silício/química , Propriedades de Superfície
4.
Anal Chem ; 90(12): 7617-7625, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29799184

RESUMO

Selective enrichment and sensitive detection of phosphopeptides are of great significance in many bioapplications. In this work, dendritic mesoporous silica nanoparticles modified with polydopamine and chelated Ti4+ (denoted DMSNs@PDA-Ti4+) were developed to improve the enrichment selectivity of phosphopeptides. The unique central-radial pore structures endowed DMSNs@PDA-Ti4+ with a high surface area (362 m2 g-1), a large pore volume (1.37 cm3 g-1), and a high amount of chelated Ti4+ (75 µg mg-1). Compared with conventional mesoporous silica-based materials with the same functionalization (denoted mSiO2@PDA-Ti4+) and commercial TiO2, DMSNs@PDA-Ti4+ showed better selectivity and a lower detection limit (0.2 fmol/µL). Moreover, 2422 unique phosphopeptides were identified from HeLa cell extracts with a high specificity (>95%) enabled by DMSNs@PDA-Ti4+, better than those in previous reports.


Assuntos
Nanopartículas/química , Neoplasias/química , Neoplasias/patologia , Fosfopeptídeos/análise , Dióxido de Silício/química , Titânio/química , Células HeLa , Humanos , Indóis/química , Estrutura Molecular , Tamanho da Partícula , Polímeros/química , Porosidade , Propriedades de Superfície
5.
J Nanosci Nanotechnol ; 13(10): 6553-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24245114

RESUMO

In this study, thermosensitive and folate functionalized poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)-ploy(N-isopropylacrylamide-co-hydroxyethyl methacrylate) (FA-Pluronic-PNH) copolymer was synthesized. The structure and molecular weight of the copolymer were confirmed by 1H NMR, FT-IR and GPC, respectively. The lower critical solution temperature (LCST) of the copolymer was 39.8 degrees C. By employing doxorubicin (DOX) as a model drug, folate receptor-targeted DOX-loaded micelles were further formed on the copolymer. The blank and DOX-loaded micelles both exhibited nearly spherical shapes and their average diameters were 35 nm and 50 nm, respectively. The in vitro release behaviors of the DOX-loaded micelles were temperature-dependent and the release rate of DOX at 42 degrees C (above LCST) was faster than that at 37 degrees C (below LCST). Furthermore, the cytotoxicity assays of free DOX and DOX-loaded micelles on human cervical cancer cell lines HeLa and human lung cancer cell lines A549 demonstrated that folate increased the cellular uptake of the micelles within targeted cells that vastly over-expressed folate receptors.


Assuntos
Ácido Fólico/química , Micelas , Poloxâmero/química , Cromatografia em Gel , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Eur J Med Res ; 28(1): 463, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37884978

RESUMO

BACKGROUND: A novel CT-linac (kilovolt fan-beam CT-linac) has been introduced into total marrow and lymphoid irradiation (TMLI) treatment. Its integrated kilovolt fan-beam CT (kV FBCT) can be used not only for image guidance (IGRT) but also to re-calculate the dose. PURPOSE: This study reported our clinical routine on performing TMIL treatment on the CT-linac, as well as dose distribution comparison between planned and re-calculated based on IGRT FBCT image sets. METHODS: 11 sets of data from 5 male and 6 female patients who had underwent the TMLI treatment with uRT-linac 506c were selected for this study. The planning target volumes consist of all skeletal bones exclusion of the mandible and lymphatic sanctuary sites. A planned dose of 10 Gy was prescribed to all skeletal bones exclusion of the mandible in two fractions and 12 Gy in two fractions was prescribed to lymphatic sanctuary sites. Each TMLI plan contained two sub-plans, one dynamic IMRT for the upper body and the other VMAT for the lower extremity. Two attempts were made to obtain homogeneous dose in the overlapping region, i.e., applying two plans with different isocenters for the treatment of two fractions, and using a dose gradient matching scheme. The CT scans, including planning CT and IGRT FBCT, were stitched to a whole body CT scan for dose distribution evaluation. RESULTS: The average beam-on time of Planupper is 30.6 min, ranging from 24.9 to 37.5 min, and the average beam-on time of Planlower is 6.3 min, ranging from 5.7 to 8.2 min. For the planned dose distribution, the 94.79% of the PTVbone is covered by the prescription dose of 10 Gy (V10), and the 94.68% of the PTVlymph is covered by the prescription dose of 12 Gy (V12). For the re-calculated dose distribution, the 92.17% of the PTVbone is covered by the prescription dose of 10 Gy (V10), and the 90.07% of the PTVlymph is covered by the prescription dose of 12 Gy (V12). The results showed that there is a significant difference (p < 0.05) between planning V10, V12 and delivery V10, V12. There is no significant difference (p > 0.05) between planned dose and re-calculated dose on selected organs, except for right lens (p < 0.05, Dmax). The actual delivered maximum dose of right lens is apparently larger than the planned dose of it. CONCLUSION: TMLI treatment can be performed on the CT-linac with clinical acceptable quality and high efficiency. Evaluation of the recalculated dose on IGRT FBCT suggests the treatment was delivered with adequate target coverage.


Assuntos
Radioterapia de Intensidade Modulada , Humanos , Masculino , Feminino , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Medula Óssea , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Irradiação Linfática , Tomografia Computadorizada por Raios X/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-34840084

RESUMO

Considering the importance of glycopeptides in the clinical diagnosis of cancer and some serious diseases, the identification of glycopeptides from complex biological samples has attracted considerable attention. Effective pre-enrichment before mass spectrometry analysis plays an important role. In this work, a kind of hydrophilic two-dimensional composites (denoted as GO@MPDA@Arg) based on mesoporous polydopamine-graphene oxide were used to selectively enrich glycopeptides in biological samples. The mesoporous polydopamine (MPDA) layer self-assembled with template Pluronic F127 provided more binding sites to load arginine, and bound arginine enhanced the hydrophilicity of the material. As a result, GO@MPDA@Arg composites exhibited excellent enrichment performance for glycopeptides, containing good selectivity (IgG digests : BSA digests = 1:50, molar ratio), low detection limit for IgG digests (10 fmol µL-1), high loading capacity for IgG digests (200 µg mg-1), and good size exclusion (IgG digests : IgG : BSA = 1:100:100, mass ratio). In addition, mouse brain tissue was selected as the actual biological sample to further study the enrichment effect of GO@MPDA@Arg composites. In three parallel experiments, a total of 401 glycopeptides belonging to 233 glycoproteins were enriched from 200 µg digestion of mouse brain extract. The enrichment results demonstrate that GO@MPDA@Arg composites have application potential for glycopeptides enrichment in protein post-translational modification research.


Assuntos
Arginina/química , Cromatografia/métodos , Glicopeptídeos/análise , Glicopeptídeos/química , Eletricidade Estática , Animais , Química Encefálica , Grafite/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imunoglobulina G/sangue , Imunoglobulina G/química , Indóis/química , Camundongos , Nanocompostos/química , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/química , Polímeros/química
8.
Anal Chim Acta ; 1169: 338628, 2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34088375

RESUMO

The detection of circulating tumor DNA (ctDNA) has increasingly received a great deal of attention considering its significance in cancer diagnosis. And the signal amplification plays an important role in the development of sensitive ctDNA biosensors. Herein, the nanocomposites (denoted as HAC-AuPt), integrating from high-active carbon (HAC) and AuPt alloy nanoparticles, were synthesized and subsequently used as a signal amplification label to fabricate a sandwich-type ctDNA electrochemical biosensor. Characterizations demonstrated that HAC presents uniform size distribution and AuPt alloy nanoparticles were successfully loaded on HAC. The current response could be amplified to a great extent by the resultant HAC-AuPt due to its excellent electrochemical property. The nanocomposites were further bounded with DNA signal probes (SPs) via Au-S or Pt-S assembly to form SPs-label. After the capture probes (CPs) were immobilized on the electrode surface, the target DNA (tDNA) and SPs-label were stepwise incubated on the CPs-modified electrode, thus forming a sandwich-type structure. By monitoring the catalytic signal of HAC-AuPt towards the reduction process of H2O2, this biosensor provided a wide linear range of 10-8 mol/L - 10-16 mol/L with a low detection limit of 3.6 × 10-17 mol/L (S/N = 3) for the detection of the tDNA. Furthermore, obvious differences in response signals among different DNAs were observed benefitting from the excellent selectivity of the biosensor. Besides, the long-term stability, reproducibility, and recovery rate were proved to be outstanding. These results indicate that the established biosensor holds a potential application in the clinical diagnosis of ctDNA.


Assuntos
Técnicas Biossensoriais , DNA Tumoral Circulante/análise , Grafite , Nanopartículas Metálicas , Ligas , Técnicas Eletroquímicas , Ouro , Peróxido de Hidrogênio , Limite de Detecção , Platina , Reprodutibilidade dos Testes
9.
Sci Rep ; 11(1): 12283, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112869

RESUMO

Radiotherapy-related caries is a complication of radiotherapy for nasopharyngeal carcinoma; however, factors influencing the occurrence, accurate prediction of onset, and protective factors of radiotherapy-related caries remain unclear. This study analyzed risk factors, disease predictors, and protective factors for radiotherapy-related caries in nasopharyngeal carcinoma. This prospective study included 138 nasopharyngeal carcinoma patients receiving radical radiotherapy at our hospital during June 2012-December 2016 and were followed up for dental caries. Patients' clinical data on radiotherapy were collected, dynamic monitoring was performed to assess changes in oral pH values, and a questionnaire survey was administered to collect patients' lifestyle habits. Time-dependent cox regression trees, event-free Kaplan-Meier curve, Mann-Whitely U test were used to analysis the results. The median follow-up time was 30 (12-60) months. Radiotherapy-related caries occurred in 28 cases (20.3%). Univariate analyses showed that radiotherapy-related caries was associated with patient's age, oral saliva pH value, green tea consumption, and radiation dose to sublingual glands, but not with the radiation dose to the parotid and submandibular glands. Multivariate analysis showed that oral saliva pH value [hazard ratio (HR) = 0.390, 95% confidence interval = 0.204-0.746] was an independent prognostic factor for radiotherapy-related caries. Patients with oral saliva pH values ≤ 5.3 in the 9th month after radiotherapy represented a significantly higher risks for radiotherapy-related caries (p < 0.001). Green tea consumption was associated with the occurrence of radiotherapy-related caries, and oral saliva pH values could predict the occurrence of radiotherapy-related caries. Limiting radiation doses to sublingual glands can reduce the occurrence of radiotherapy-related caries.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária/etiologia , Concentração de Íons de Hidrogênio , Carcinoma Nasofaríngeo/complicações , Radioterapia/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/radioterapia , Modelos de Riscos Proporcionais , Radioterapia/métodos , Medição de Risco , Fatores de Risco , Fatores de Tempo
10.
Anal Chim Acta ; 1053: 89-97, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30712573

RESUMO

As pyrophosphate ion (PPi) and pyrophosphatase (PPase) play crucial roles in the pathological process of arthritis, determination of PPi and PPase in biological fluids turns to be of great importance for clinical diagnosis and therapy of arthritic diseases. In this work, we proposed a new fluorescent assay for PPi and PPase activity detection based on the competitive coordination chemistry of Fe3+ between PPi and an in situ formed fluorescent polydopamine (PDA). FeCo layered double hydroxide (FeCo-LDH) was explored as a peroxidase mimic to facilitate the in situ formation of fluorescent PDA from dopamine mediated by low-concentration H2O2 within 30 min; The formed fluorescent PDA could be significantly quenched by Fe3+ through forming a PDA-Fe3+ complex structure; When PPi existed, it coordinated Fe3+ competitively against PDA and inhibited the fluorescence quenching of PDA by Fe3+; When PPi was hydrolyzed under the catalysis of PPase, the Fe3+ ion could quench the fluorescence of the formed PDA again. With these principles, our fluorescent assay was able to detect PPi and PPase activity specifically, providing detection limits down to 54 µM and 0.13 U/L, respectively. Furthermore, accurate determination of PPi and PPase activity in spiked human serum was also demonstrated using the developed assay.


Assuntos
Materiais Biomiméticos/química , Análise Química do Sangue/métodos , Difosfatos/análise , Ensaios Enzimáticos/métodos , Indóis/química , Peroxidase/metabolismo , Polímeros/química , Pirofosfatases/metabolismo , Catálise , Cobalto/química , Compostos Férricos/química , Corantes Fluorescentes/química , Humanos , Hidróxidos/química
11.
Radiat Oncol ; 13(1): 248, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30558631

RESUMO

BACKGROUND: To report our experience in planning and delivering total marrow irradiation (TMI) and total marrow and lymphatic irradiation (TMLI) in patients with hematologic malignancies. METHODS: Twenty-seven patients undergoing bone marrow transplantation were treated with TMI/TMLI using Helical Tomotherapy (HT). All skeletal bones exclusion of the mandible comprised the treatment target volume and, for TMLI, lymph node chains, liver, spleen and/or brain were also included according to the clinical indication. Planned dose of 8Gy in 2 fractions was delivered over 1 day for TMI while 10Gy in 2 fractions BID was used for TMLI. Organs at risk (OAR) contoured included the brain, brainstem, lens, eyes, optic nerves, parotids, oral cavity, lungs, heart, liver, kidneys, stomach, small bowel, bladder and rectum. In particular, a simple method to avoid hot or cold doses in the overlapping region was implemented and the plan sum was adopted to evaluate dose inhomogeneity. Furthermore, setup errors from 54 treatments were summarized to gauge the effectiveness of immobilization. RESULTS: During the TMI/TMLI treatment, no acute adverse effects occurred during the radiation treatment. Two patients suffered nausea or vomiting right after radiation course. For the 9 patients treated with TMI, the median dose reduction of major organs varied 30-65% of the prescribed dose, substantially lower than the traditional total body irradiation (TBI). Meanwhile, average biological equivalent doses to OARs with 8Gy/2F TMI approach were not different from the conventional 12Gy/6F TMI approach. In the dose junction region, the 93% of PTV was covered by the prescribed dose without obvious hotspots. For the 27 patients, the overall setup corrections were lower than 3 mm except those in the SI direction for abdomen-pelvis region, demonstrating excellent immobilization. CONCLUSION: The present study confirmed the technical feasibility of HT-based TMI/TMLI delivering 8-10Gy in 2 fractions over 1 day. For patients undergoing hematopoietic cell transplantation the proposed 8Gy/2F TMI (or 10Gy/2F TMLI) strategy may be a novel approach to improve delivery efficiency, increase effective radiation dose to target while maintaining low risk of severe organ toxicities.


Assuntos
Medula Óssea/efeitos da radiação , Neoplasias Hematológicas/radioterapia , Sistema Linfático/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Adolescente , Adulto , Criança , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Prognóstico , Dosagem Radioterapêutica , Estudos Retrospectivos , Adulto Jovem
12.
J Biomater Sci Polym Ed ; 26(8): 468-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25780935

RESUMO

Functional polymeric micelles play an important role in the efficient delivery of therapeutic drugs into tumours. In this study, a functional drug delivery platform with ligands for targeting and fluorescent imaging was designed based on Pluronic F127 (PF127). Using folic acid (FA) and fluorescein isothiocyanate (FITC) to chemically conjugate with PF127, two functional polymers, Pluronic F127-FA (PF127-FA) and Pluronic F127-FITC (PF127-FITC), were synthesized. Solasodine-loaded micelles were then prepared via the thin-film hydration method. By employing A549 and HeLa cells, the results of in vitro cell assays performed using confocal laser scanning microscopy and flow cytometry suggested that the proposed micelles could provide the desired specific targeting and fluorescent imaging functions. In addition, the results of in vitro cytotoxicity experiments showed that the growth inhibition rates of A549 and HeLa cells treated with solasodine-loaded micelles were remarkably higher than those of cells treated with free solasodine. Solasodine-loaded micelles exhibited a more distinct inhibitory effect against HeLa cells than against A549 cells. Thus, an effective drug delivery system for targeting and imaging cancer cells was developed.


Assuntos
Portadores de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Imagem Óptica/métodos , Poloxâmero/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Fluoresceína-5-Isotiocianato/química , Ácido Fólico/administração & dosagem , Ácido Fólico/farmacologia , Células HeLa , Humanos , Micelas , Neoplasias/patologia , Poloxâmero/síntese química , Alcaloides de Solanáceas/administração & dosagem , Alcaloides de Solanáceas/farmacologia
13.
Talanta ; 137: 18-24, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25770601

RESUMO

In the present work, a high-performance enzyme-based electrochemical sensor for the detection of superoxide anion radical (O2(●-)) is reported. Firstly, we employed a facile approach to synthesize PtPd nanoparticles (PtPd NPs) on chemically reduced graphene oxide (RGO) coated with polydopamine (PDA). The prepared PtPd-PDARGO composite was well characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectra, X-ray diffraction, X-ray photoelectron spectroscopy and electrochemical methods. Then the assembled composite was used as a desired electrochemcial interface for superoxide dismutase (SOD) immobilization. Owing to the PDA layer as well as the synergistic effect of PtPd NPs, the fabricated SOD/PtPd-PDARGO sensor exhibited an outstanding sensitivity of 909.7 µA mM(-1) cm(-2) upon O2(●-) in a linear range from 0.016 mM to 0.24 mM (R(2)=0.992), with a low detection limit of 2 µM (S/N=3) and excellent selectivity, good reproducibility as well as favorable long-term stability.


Assuntos
Técnicas Biossensoriais/métodos , Grafite/química , Indóis/química , Nanopartículas Metálicas/química , Óxidos/química , Polímeros/química , Superóxido Dismutase/metabolismo , Superóxidos/análise , Técnicas Biossensoriais/instrumentação , Eletroquímica , Eletrodos , Paládio/química , Platina/química , Reprodutibilidade dos Testes , Superóxido Dismutase/química , Superóxidos/química
14.
J Biomed Nanotechnol ; 10(5): 795-802, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24734532

RESUMO

In the present work, we propose a new multifunctional micelle, co-self-assembled from different monofunctional copolymers, for tumor targeting and fluorescent and electron spin resonance (ESR) dual detection. Firstly, a poly(D,L-lactic acid)-b-poly(N-isopropyl methacrylamide-co-N-isopropylmaelic acid-co-10-undecenoic acid)-b-poly(N-acryloxysuccinimide) (PLA-PNNUA-PNAS) copolymer, with pH-dependent thermo-responsive properties, was synthesized. The copolymer was synthesized using reversible addition fragmentation chain transfer (RAFT) polymerization method, after which it was further used as a parent copolymer to combine with folic acid (FA), fluorescein isothiocyanate (FITC) and 4-amino-2,2,6,6-tetramethylpiperidin-1-oxyl (4-NH2-TEMPO), respectively, resulting into three new monofunctional copolymers. Finally, the multifunctional copolymer micelle was easily then fabricated, through co-self-assembly, using the monofunctional copolymers. The results from in vitro cell assays indicated that the proposed micelle was able to provide desired multifunctional properties, including tumor specific targeting and fluorescent and ESR dual detection. Additionally, the parent copolymer allowed conjugation with other ligands to prepare them for more functional copolymers attachment for future potential applications. More importantly, the multifunctional properties of the copolymer micelles could be rationally tailored, able for given purposes.


Assuntos
Resinas Acrílicas/química , Materiais Biocompatíveis/química , Ácido Láctico/química , Micelas , Neoplasias Experimentais/química , Polímeros/química , Succinimidas/química , Animais , Linhagem Celular Tumoral , Cristalização/métodos , Endocitose , Substâncias Macromoleculares/química , Teste de Materiais , Camundongos , Conformação Molecular , Células NIH 3T3 , Neoplasias Experimentais/fisiopatologia , Tamanho da Partícula , Poliésteres , Propriedades de Superfície
15.
Int J Pharm ; 458(1): 110-7, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24126038

RESUMO

The blood-brain barrier (BBB) restricts the transfer and delivery of most drug substances to brain. In this study, a novel nano-drug delivery system for brain-targeting was developed and investigated in vitro and in vivo. Lactoferrin (Lf) was selected as a brain-targeting ligand and conjugated to ß-cyclodextrin (ß-CD) via the heterobifunctional polyethyleneglycol (PEG) linker NHS-PEG-MAL, yielding Lf conjugated ß-cyclodextrin (Lf-CD). UV-vis, FTIR, NMR and transmission electron microscopy (TEM) techniques clearly demonstrated the successful synthesis of Lf-CD nanoparticles with the average diameter of 92.9 ± 16.5 nm. Using near-infrared fluorescent dye IR-775 chloride (IR) as a model compound of poorly water-soluble drugs, IR-loaded Lf-CD nanoparticles (Lf-CD/IR) were successfully prepared with a high entrapment efficiency of 98.1 ± 4.8%. Biodistribution and pharmacokinetics of Lf-CD/IR were evaluated in KM mice after intravenous administration. The results of tissue distribution studies revealed that Lf-CD/IR treatment showed greatly improved BBB transport efficiency. In addition, AUC0-2h of IR in brain after Lf-CD/IR treatment was seven fold higher compared with that of IR treatment without Lf-CD nano-carriers, demonstrating that the introduction of Lf-CD drug-delivery system positively resulted in a higher AUC located in brain tissue. These results provide evidence that Lf-CD nanoparticles could be exploited as a potential brain-targeting drug delivery system for hydrophobic drugs and diagnostic reagents which normally fail to pass through the BBB.


Assuntos
Encéfalo/metabolismo , Portadores de Fármacos/química , Lactoferrina/administração & dosagem , Lactoferrina/química , Nanopartículas/química , beta-Ciclodextrinas/administração & dosagem , beta-Ciclodextrinas/química , Animais , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Portadores de Fármacos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Camundongos , Nanopartículas/administração & dosagem , Células PC12 , Tamanho da Partícula , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Ratos , Distribuição Tecidual
16.
Nanomedicine (Lond) ; 6(2): 225-31, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21385125

RESUMO

AIMS: In this article we report our recent developments in the field of electron paramagnetic resonance oximetry. MATERIALS & METHODS: Novel synthesized ferrocenyl nitroxide radicals (FcN)-1-6 were evaluated to determine their electron paramagnetic resonance oxygen responsiveness and reduction resistance. The 3-ferrocenyl-N-(oxyl-2,2,6,6-tetramethylpiperidin-4-yl) butanamide radical (FcN-6), with outstanding electron paramagnetic resonance oxygen sensitivity, was encapsulated in Pluronic F-127 polymeric nanoparticles. RESULTS: The nanoparticles exhibited good oxygen sensitivity, long-term stability of responsiveness, targeting to lung, liver and tumor, and low toxicity. CONCLUSION: These features make this novel nanoparticle especially valuable for mapping O2 concentrations in the body and monitoring the oxygen level inside tissues.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Compostos Ferrosos/química , Nanopartículas/química , Óxidos de Nitrogênio/química , Oximetria/métodos , Oxigênio/análise , Animais , Carcinoma Pulmonar de Lewis/diagnóstico , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Poloxâmero/química , Sensibilidade e Especificidade
17.
Shanghai Kou Qiang Yi Xue ; 20(3): 265-8, 2011 Jun.
Artigo em Zh | MEDLINE | ID: mdl-21779734

RESUMO

PURPOSE: To compare the microstructure and ESR dosimetry between tetracycline-stained teeth and normal teeth by means of scanning electron microscopy (SEM) and electron spin resonance (ESR) dosimeter. METHODS: Ten first or second premolars of tetracycline-stained teeth and ten normal teeth extracted for adult orthodontic persons were collected. The enamel on the surface and the dentine on the cross section of both type of teeth were observed with SEM. The ESR signal of teeth components (enamel and dentine) was evaluated by X-band ESR spectroscopy. RESULTS: Compared with normal teeth, the enamel of tetracycline-stained teeth was of porosity and the enamel prisms were irregular. The dentinal tubules and dentinal matrix also showed obvious difference between the two type of teeth. The X-band ESR spectrum of tetracycline-stained teeth was different from normal teeth. CONCLUSION: The microstructure and the native radicals have significant effect on the tetracyclines deposited in the teeth.


Assuntos
Esmalte Dentário , Tetraciclina , Descoloração de Dente , Adulto , Dente Pré-Molar , Dentina , Humanos , Microscopia Eletrônica de Varredura , Dente
18.
J Colloid Interface Sci ; 362(2): 584-93, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21794871

RESUMO

The fabrication of a new amphiphilic block copolymer composed of a poly DL-lactic acid (PLA) hydrophobic backbone and pH dependent thermo-sensitive poly (N-isopropyl) methacrylamide-co-N-isopropylmaleamic acid-co-10-undecenoic acid (PNIPAAm-co-NIPMMA-co-UA) entities as hydrophilic domains as well as carrying 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) residues for electron spin resonance (ESR) labeling is reported. The lower critical solution temperature (LCST) of the copolymer was determined by optical absorbance measurements. The LCST was pH dependent and varied in a narrow practical range, 35.4 °C at pH 5.0, 37.5 °C at pH 6.5 and 39.4 °C at pH 7.4, which was below, near and above nominal physiological temperature respectively. The assembly of the copolymer into micelles in aqueous solution at temperatures below the LCST was confirmed by FT-IR, (1)H NMR and fluorescence spectroscopy. It is demonstrated that the anticancer drug, 5-fluorouracil (5-FU) can be loaded effectively within the polymeric micelles and released in response to environmental stimuli- namely, pH and temperature.


Assuntos
Óxidos N-Cíclicos/química , Portadores de Fármacos/química , Polímeros/química , Espectroscopia de Ressonância de Spin Eletrônica , Fluoruracila/administração & dosagem , Concentração de Íons de Hidrogênio , Micelas , Marcadores de Spin , Temperatura
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