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1.
J Nanobiotechnology ; 18(1): 58, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32272948

RESUMO

BACKGROUND: The anti-angiogenic fusion protein RBDV-IgG1 Fc (RBDV), which comprises the receptor-binding domain of vascular endothelial growth factor-A (VEGF-A), has shown antitumour effects by reducing angiogenesis in vivo. This study used the cationic lipoplex lipo-PEG-PEI-complex (LPPC) to simultaneously encapsulate both the RBDV targeting protein and the RBDV plasmid (pRBDV) without covalent bonds to assess VEGFR targeting gene therapy in mice with melanoma in vivo. RESULTS: LPPC protected the therapeutic transgene from degradation by DNase, and the LPPC/RBDV complexes could specifically target VEGFR-positive B16-F10 cells both in vitro and in vivo. With or without RBDV protein-targeting direction, the pRBDV-expressing RBDV proteins were expressed and reached a maximal concentration on the 7th day in the sera after transfection in vivo and significantly elicited growth suppression against B16-F10 melanoma but not IgG1 control proteins. In particular, LPPC/pRBDV/RBDV treatment with the targeting molecules dramatically inhibited B16-F10 tumour growth in vivo to provide better therapeutic efficacy than the treatments with gene therapy with IgG1 protein targeting or administration of a protein drug with RBDV. CONCLUSIONS: The simultaneous combination of the LPPC complex with pRBDV gene therapy and RBDV protein targeting might be a potential tool to conveniently administer targeted gene therapy for cancer therapy.


Assuntos
Inibidores da Angiogênese/genética , Terapia Genética/métodos , Lipossomos/química , Melanoma Experimental/terapia , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Células 3T3 , Animais , Linhagem Celular Tumoral , Proliferação de Células , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/metabolismo , Masculino , Melanoma Experimental/mortalidade , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Plasmídeos/química , Plasmídeos/genética , Plasmídeos/uso terapêutico , Domínios Proteicos/genética , Receptores de Fatores de Crescimento do Endotélio Vascular/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/isolamento & purificação , Taxa de Sobrevida , Transplante Homólogo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
J Nanobiotechnology ; 17(1): 25, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30728015

RESUMO

BACKGROUND: A cationic liposome-PEG-PEI complex (LPPC) was employed as a carrier for achieving targeted delivery of drug to human epidermal growth factor receptor-2 (HER2/neu)-expressing breast cancer cells. LPPC can be easily loaded with an anti-tumor drug and non-covalently associated with an anti-tumor antibody such as Herceptin that is clinically used to rapidly form immunoparticles within 1 h. RESULTS: Drug-loaded LPPC have an average size about 250 nm and a zeta potential of about 40 mV. Herceptin was complexed onto surface of the LPPC to form the drug/LPPC/Herceptin complexes. The size of curcumin/LPPC/Herceptin complexes were 280 nm and the zeta potentials were about 23 mV. Targeting ability of this delivery system was demonstrated through specific binding on surface of cells and IVIS images in vivo, which showed specific binding in HER2-positive SKBR3 cells as compared to HER2-negative Hs578T cells. Only the drug/LPPC/Herceptin complexes displayed dramatically increased the cytotoxic activity in cancer cells. Both in vitro and in vivo results indicated that Herceptin adsorbed on LPPC directed the immunocomplex towards HER2/neu-positive cells but not HER2/neu-negative cells. The complexes with either component (curcumin or doxorubicin) used in the LPPC-delivery system provided a better therapeutic efficacy compared to the drug treatment alone and other treatment groups, including clinical dosages of Herceptin and LipoDox, in a xenografted model. CONCLUSIONS: LPPC displays important clinical implications by easily introducing a specific targeting characteristic to drugs utilized for breast cancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Polietilenoglicóis/química , Polietilenoimina/análogos & derivados , Receptor ErbB-2/metabolismo , Trastuzumab/administração & dosagem , Animais , Antineoplásicos/imunologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Curcumina/administração & dosagem , Doxorrubicina/administração & dosagem , Liberação Controlada de Fármacos , Feminino , Xenoenxertos , Humanos , Lipossomos , Células MCF-7 , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Polietilenoimina/química , Propriedades de Superfície , Trastuzumab/imunologia
3.
J Nanobiotechnology ; 14: 11, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26892504

RESUMO

BACKGROUND: Tamoxifen is currently used for the treatment of both early and advanced estrogen receptor (ER) positive breast cancer in pre- and post-menopausal women. However, using tamoxifen routinely to inhibit endogenous or exogenous estrogen effects is occasionally difficult because of its potential side effects. OBJECTIVES: The aim of this study is to design a local drug delivery system to encapsulate tamoxifen for observing their efficacy of skin penetration, drug accumulation and cancer therapy. METHODS: A cationic liposome-PEG-PEI complex (LPPC) was used as a carrier for the encapsulation of tamoxifen and forming 'LPPC/TAM' for transdermal release. The cytotoxicity of LPPC/TAM was analyzed by MTT. The skin penetration, tumor growth inhibition and organ damages were measured in xenograft mice following transdermal treatment. RESULTS: LPPC/TAM had an average size less than 270 nm and a zeta-potential of approximately 40 mV. LPPC/TAM displayed dramatically increased the cytotoxic activity in all breast cancer cells, especially in ER-positive breast cancer cells. In vivo, LPPC drug delivery helped the fluorescent dye penetrating across the skim and accumulating rapidly in tumor area. Administration of LPPC/TAM by transdermal route inhibited about 86 % of tumor growth in mice bearing BT474 tumors. This local treatment of LPPC/TAM did not injury skin and any organs. CONCLUSION: LPPC-delivery system provided a better skin penetration and drug accumulation and therapeutic efficacy. Therefore, LPPC/TAM drug delivery maybe a useful transdermal tool of drugs utilization for breast cancer therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Lipossomos/administração & dosagem , Tamoxifeno/administração & dosagem , Administração Cutânea , Animais , Mama/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Células HEK293 , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Polietilenoglicóis/administração & dosagem , Polietilenoimina/administração & dosagem , Polietilenoimina/análogos & derivados
4.
Small ; 10(23): 4886-94, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25059988

RESUMO

Light-responsive hydrogel particles with multi-compartmental structure are useful for applications in microreactors, drug delivery and tissue engineering because of their remotely-triggerable releasing ability and combinational functionalities. The current methods of synthesizing multi-compartmental hydrogel particles typically involve multi-step interrupted gelation of polysaccharides or complicated microfluidic procedures with limited throughput. In this study, a two-step sequential gelation process is developed to produce agarose/alginate double network multi-compartmental hydrogel particles using droplets assemblies induced by superhydrophobic surface as templates. The agarose/alginate double network multi-compartmental hydrogel particles can be formed with diverse hierarchical structures showing combinational functionalities. The synthesized hydrogel particles, when loaded with polypyrrole (PPy) nanoparticles that act as photothermal nanotransducers, are demonstrated to function as near-infrared (NIR) light triggerable and deformation-free hydrogel materials. Periodic NIR laser switching is applied to stimulate these hydrogel particles, and pulsatile release profiles are collected. Compared with massive reagents released from single-compartmental hydrogel particles, more regulated release profiles of the multi-compartmental hydrogel particles are observed.


Assuntos
Hidrogéis/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Alginatos/química , Cobre/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Raios Infravermelhos , Lasers , Luz , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanopartículas/química , Nanotubos/química , Polímeros/química , Pirróis/química , Sefarose/química , Engenharia Tecidual/métodos , Água/química
5.
J Exp Clin Cancer Res ; 42(1): 29, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36691089

RESUMO

BACKGROUND: The applicability and therapeutic efficacy of specific personalized immunotherapy for cancer patients is limited by the genetic diversity of the host or the tumor. Side-effects such as immune-related adverse events (IRAEs) derived from the administration of immunotherapy have also been observed. Therefore, regulatory immunotherapy is required for cancer patients and should be developed. METHODS: The cationic lipo-PEG-PEI complex (LPPC) can stably and irreplaceably adsorb various proteins on its surface without covalent linkage, and the bound proteins maintain their original functions. In this study, LPPC was developed as an immunoregulatory platform for personalized immunotherapy for tumors to address the barriers related to the heterogenetic characteristics of MHC molecules or tumor associated antigens (TAAs) in the patient population. Here, the immune-suppressive and highly metastatic melanoma, B16F10 cells were used to examine the effects of this platform. Adsorption of anti-CD3 antibodies, HLA-A2/peptide, or dendritic cells' membrane proteins (MP) could flexibly provide pan-T-cell responses, specific Th1 responses, or specific Th1 and Th2 responses, depending on the host needs. Furthermore, with regulatory antibodies, the immuno-LPPC complex properly mediated immune responses by adsorbing positive or negative antibodies, such as anti-CD28 or anti-CTLA4 antibodies. RESULTS: The results clearly showed that treatment with LPPC/MP/CD28 complexes activated specific Th1 and Th2 responses, including cytokine release, CTL and prevented T-cell apoptosis. Moreover, LPPC/MP/CD28 complexes could eliminate metastatic B16F10 melanoma cells in the lung more efficiently than LPPC/MP. Interestingly, the melanoma resistance of mice treated with LPPC/MP/CD28 complexes would be reversed to susceptible after administration with LPPC/MP/CTLA4 complexes. NGS data revealed that LPPC/MP/CD28 complexes could enhance the gene expression of cytokine and chemokine pathways to strengthen immune activation than LPPC/MP, and that LPPC/MP/CTLA4 could abolish the LPPC/MP complex-mediated gene expression back to un-treatment. CONCLUSIONS: Overall, we proved a convenient and flexible immunotherapy platform for developing personalized cancer therapy.


Assuntos
Melanoma , Polímeros , Animais , Camundongos , Citocinas/metabolismo , Imunoterapia , Lipossomos/química
6.
Nanomedicine ; 8(3): 318-27, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21704596

RESUMO

A cationic liposome-PEG-PEI complex (LPPC) was used as a carrier for the encapsulation of hydrophobic curcumin to give curcumin/LPPC. Curcumin/LPPC had an average size less than 270 nm and a zeta potential of approximately 40 mV. The LPPC encapsulation efficiency for curcumin was about 45%. The authors found it surprising that the cytotoxic activity of the curcumin/LPPC was fivefold higher than curcumin when tested on curcumin-sensitive cells and 20-fold more active against curcumin-resistant cells. Curcumin/LPPC treatment caused a cell cycle arrest at G2/M phase, which rapidly resulted in apoptosis. The increased cytotoxic activity of curcumin/LPPC is likely attributable to its rapid accumulation in the cell. In vivo, administration of curcumin/LPPC inhibited about 60 - 90% of tumor growth in mice bearing CT-26 or B16F10 cells. These results demonstrate LPPC encapsulation technology is able to enhance the effects of antitumor drugs. Use of this technology may provide a new tool for cancer therapy, especially for drug-resistant cancer. From the Clinical Editor: This team of investigators used a cationic liposome-PEG-PEI complex (LPPC) to encapsulate curcumin. The different delivery method resulted in the five-fold increase of cytotoxic activity against curcumin-sensitive cells and twenty-fold against curcumin-resistant cells.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Lipossomos/química , Polietilenoglicóis/química , Polietilenoimina/análogos & derivados , Animais , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Química Farmacêutica , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Polietilenoimina/química
7.
Prep Biochem Biotechnol ; 42(5): 448-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22897767

RESUMO

Gene therapy provides a novel strategy and a new hope for patients with cancer. Unfortunately, the specifics of the delivery systems or the promoters have not achieved the specified efficacy so far, and the perfection of either system will be extremely difficult. In this study, we introduce a simple concept that a combination of a partially specific delivery system and a partially specific promoter activity may achieve a more specific effect on transgenic expression in target cells. The first section describes tumor-related transcription factors that were assayed in tumors or rapidly proliferating cells to determine their activities. The activities of nuclear factor (NF)-κB, CREB, and HIF-1 were higher, and three copies of each response element were used to construct a transcription factor-based synthetic promoter (TSP). The results showed that the expression of the TSP was active and partially specific to cell types. As described in the second section, the multifunctional peptide RGD-4C-HA was designed to absorb polyethyleneimine (PEI) molecules, and this complex was targeted to integrin αvß3 on B16F10 cells. The results indicated that RGD-4C-HA could associate with PEI to mediate specific targeting in vitro. Finally, the combination of the PEI-peptide complex and TSP could enhance the specifically transgenic expression in B16F10 cells. This strategy has been proven to work in vitro and might potentially be used for specific gene therapy in vivo.


Assuntos
Expressão Gênica , Marcação de Genes/métodos , Técnicas de Transferência de Genes , Proteínas de Neoplasias/genética , Elementos de Resposta , Proteína de Ligação a CREB/química , Proteína de Ligação a CREB/genética , Linhagem Celular Tumoral , Terapia Genética , Vetores Genéticos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/química , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Integrina alfaVbeta3/antagonistas & inibidores , Integrina alfaVbeta3/genética , NF-kappa B/química , NF-kappa B/genética , Proteínas de Neoplasias/química , Neoplasias/patologia , Neoplasias/terapia , Oligopeptídeos/genética , Polietilenoimina/química , Transfecção
8.
Biotechnol Bioeng ; 108(6): 1318-27, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21192002

RESUMO

Most of the currently available targeting vectors are produced via the linkage of targeting molecules. However, the coupling process is complicated, and the covalent linkage may attenuate the activity of certain targeting molecules. In this study, we have developed a cationic liposome complexed with polyethylenimine and polyethylene glycol polymers (LPPC) that can capture various proteins without covalent conjugation. Characterizations of prepared LPPC revealed that the maximal-binding capacity was about 170 µg of bovine serum albumin to 40 µg of sphere-shaped LPPC (180 nm). The proteins were essentially located at or near the surface when analyzed by atomic force or transmission electron microscopy. We demonstrate that polyethylenimine was an essential component to bind the proteins. Upon the saturation of captured proteins, a given protein could not be displaced by other additional proteins and still retained its biological activity. Using a variety of functional proteins, we show some typical examples of the utility of incorporated beta-glucuronidase and antibodies onto the LPPC. The beta-glucuronidase can be used for the study of antigen-antibody interactions, whereas in studies with the antibody complex, we used anti-CD3 as an agonist to stimulate the proliferation of peripheral blood mononuclear cells via a receptor-mediated mechanism and anti-VEGFR for cell staining. In conclusion, the prepared LPPC can provide a platform to capture biologically and biochemically functional proteins on its surface for various applications, such as cell signaling, cell profiling, noncovalent enzyme-linked immunoassays, and others not mentioned.


Assuntos
Polietilenoglicóis/metabolismo , Polietilenoimina/metabolismo , Proteínas/metabolismo , Animais , Células 3T3 BALB , Bovinos , Células Cultivadas , Humanos , Lipossomos/metabolismo , Camundongos , Ligação Proteica , Soroalbumina Bovina/metabolismo
9.
Nanoscale ; 13(48): 20531-20540, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34859803

RESUMO

Lymphocytes play a vital role in immunosurveillance through sensing biomolecules and eliminating targeted invaders. Compared with conventional therapies that depend on drug loading, lymphocytes are advantageous as they are able to ensure self-regulated therapeutics. Here, novel multi-compartmental DNA hydrogel particles were synthesized using a microfluidic assembly for intelligent cancer treatment via the logic-based control of siRNA release without external stimulation. The sensing sequence (D1) was compartmentalized from the treatment sequence (D2) with the use of core-shell DNA hydrogel particles. When D1 detects a cancer-associated biomarker, miRNA-21, a sequence cascade is triggered to release siRNA from D2, effectively eliminating the targeted cancer cells via lymphocyte-inspired precision medicine.


Assuntos
Hidrogéis , Microfluídica , DNA , Hidrogel de Polietilenoglicol-Dimetacrilato , Linfócitos , Medicina de Precisão
10.
Lab Chip ; 20(3): 626-633, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31919490

RESUMO

Bacterial cellulose (BC), a renewable type of cellulose, has been used in the manufacture of foods, cosmetics, and biomedical products. To produce BC, a high-throughput single-bacterium measurement is necessary to identify the functional bacteria that can produce BC with sufficient amount and desirable morphology. In this study, a continuous-flow intelligent optofluidic device was developed to enable high-throughput single-bacterium profiling of BC. Single bacteria were incubated in agarose hydrogel particles to produce BC with varied densities and structures. An intelligent convolutional neural network (CNN) computational method was developed to analyze the scattering patterns of BC. The BC production and morphology were determined with a throughput of ∼35 bacteria per second. A total of ∼105 single-bacterium BC samples were characterized within 3 hours. The high flexibility of this approach facilitates high-throughput comprehensive single-cell production analysis for a range of applications in engineering biology.


Assuntos
Acetobacteraceae/química , Materiais Biocompatíveis/metabolismo , Celulose/biossíntese , Gluconacetobacter xylinus/química , Dispositivos Lab-On-A-Chip , Acetobacteraceae/metabolismo , Materiais Biocompatíveis/química , Celulose/química , Gluconacetobacter xylinus/metabolismo , Fenômenos Ópticos
11.
Adv Healthc Mater ; 8(4): e1801277, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30672156

RESUMO

Immunoassays are an important tool in various bioanalytical settings, such as clinical diagnostics, biopharmaceutical analysis, environmental monitoring, and food testing. An enzyme-linked immunosorbent assay (ELISA) is usually used to amplify immunoassay signals; however, it requires labor-intensive and time-consuming procedures, which hinders its application to rapid cytokine detection. In this study, a nano-in-micro composite system, where immunosensing polystyrene beads (≈320 nm) are incorporated within a stimuli-responsive microgel matrix (≈40 µm) via microfluidics, is investigated. The intrinsic volume phase-transition change properties of the smart microgels allows an enzyme-free enhanced immunoassay, enabling instant enhancement in signal-to-noise ratios of ≈5-fold. This nano-in-micro hydrogel composite offers a simple yet highly effective method for sensitive and multiplexed cytokine analysis without complex enzyme-based signal amplification steps, greatly benefitting advanced immune medicine.


Assuntos
Hidrogéis/química , Técnicas Analíticas Microfluídicas , Nanocompostos/química , Poliestirenos/química , Humanos , Imunoensaio
12.
Int J Nanomedicine ; 14: 1119-1130, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863049

RESUMO

BACKGROUND: Protein or peptide drugs are emerging therapeutics for treating human diseases. However, current protein drugs are typically limited to acting on extracellular/cell membrane components associated with the diseases, while intracellular delivery of recombinant proteins replaces or replenishes faulty/missing proteins and remains inadequate. In this study, we developed a convenient and efficient intracellular protein delivery vehicle. MATERIALS AND METHODS: A cationic liposomal polyethylenimine and polyethylene glycol complex (LPPC) was developed to noncovalently capture proteins for protein transfer into cells via endocytosis. ß-glucuronidase (ßG) was used in vitro and in vivo as a model enzyme to demonstrate the enzymatic activity of the intracellular transport of a protein. RESULTS: The endocytosed protein/LPPC complexes escaped from lysosomes, and the bound protein dissociated from LPPC in the cytosol. The enzymatic activity of ßG was well preserved after intracellular delivery in vitro and in vivo. CONCLUSION: Using LPPC as an intracellular protein transporter for protein therapeutics, we illustrated that LPPC may be an effective and convenient tool for studying diseases and developing therapeutics.


Assuntos
Espaço Intracelular/química , Polietilenoglicóis/química , Polietilenoimina/análogos & derivados , Proteínas/uso terapêutico , Células 3T3 , Adsorção , Animais , Bovinos , Morte Celular , Fluoresceína-5-Isotiocianato/química , Fluorescência , Glucuronidase/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Células Hep G2 , Humanos , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Polietilenoimina/química , Estabilidade Proteica , Soroalbumina Bovina/química , Eletricidade Estática
13.
Laryngoscope ; 117(7): 1280-2, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17603327

RESUMO

Tracheobronchial foreign body (FB) aspiration is a common problem worldwide, and the aspired objects can be very difficult to remove. Bronchoscopic removal of airway FBs can be safely accomplished with both rigid as well as flexible bronchoscopes. It is well known that a rigid bronchoscope more easily removes large FBs located in the central bronchi. A wide variety of instruments, such as biopsy forceps, Fogarty balloon catheters, alligator forceps, or wire baskets, are commonly available for removal. Herein, we report the case of a 75-year-old man with an airway dental prosthesis, the shape and composition of which complicated its extraction from the nearly totally occluded left main bronchus, using biopsy forceps and wire baskets. We describe the successful extraction of the challenging FB with a flexible bronchoscope in concert with wire loop snares and the avoidance of rigid bronchoscopy or thoracotomy.


Assuntos
Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/terapia , Broncoscopia/métodos , Prótese Dentária , Corpos Estranhos/complicações , Otolaringologia/instrumentação , Idoso , Desenho de Equipamento , Estudos de Viabilidade , Humanos , Masculino
14.
Adv Healthc Mater ; 5(23): 2983-2992, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27805793

RESUMO

Bacterial cellulose (BC) is a biocompatible material with high purity and robust mechanical strength used to fabricate desirable scaffolds for 3D cell culture and wound healing. However, the chemical resistance of BC and its insolubility in the majority of solutions make it difficult to manipulate using standard chemical methods. In this study, a microfluidic process is developed to produce hollow BC microspheres with desirable internal structures and morphology. Microfluidics is used to generate a core-shell structured microparticle with an alginate core and agarose shell as a template to encapsulate Gluconacetobacter xylinus for long-term static culture. G. xylinus then secretes BC, which becomes entangled within the shell of the structured hydrogel microparticles and forms BC microspheres. The removal of the hydrogel template via thermal-chemical treatments yields robust BC microspheres exhibiting a hollow morphology. These hollow microspheres spontaneously assemble as functional units to form a novel injectable scaffold. In vitro, a highly porous scaffold is created to enable effective 3D cell culture with a high cell proliferation rate and better depth distribution. In vivo, this injectable scaffold facilitates tissue regeneration, resulting in rapid wound-healing in a Sprague Dawley rat skin model.


Assuntos
Celulose/administração & dosagem , Celulose/química , Gluconacetobacter xylinus/química , Cicatrização/efeitos dos fármacos , Animais , Técnicas de Cultura de Células/métodos , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Injeções/métodos , Masculino , Microfluídica/métodos , Microesferas , Porosidade , Ratos , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Engenharia Tecidual/métodos
15.
Medicine (Baltimore) ; 95(20): e3735, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27196497

RESUMO

Treatment of periodontal diseases has been associated with benefit outcomes for patients with chronic obstructive pulmonary disease (COPD). However, no population-based cohort study has been conducted. We evaluated this relationship by retrospective cohort study using a large population data.Using the National Health Insurance claims data of Taiwan, we identified 5562 COPD patients with periodontal diseases who had received periodontal treatment as the treatment group. The comparison group was selected at a 1:1 ratio matched by the propensity score estimated with age, sex, date of COPD diagnosis and periodontal treatment, and comorbidities. Both groups were followed up for 5 years to compare risks of acute exacerbation, pneumonia, and acute respiratory failure.The incidence rates of adverse respiratory events were significantly lower in the treatment group than in the comparison group: 3.79 versus 4.21 per 100 person-years for emergency room visits, 2.75 versus 3.65 per 100 person-years for hospitalizations, and 0.66 versus 0.75 per 100 person-years for intensive care unit admissions. The treatment group also had a 37% reduced risk of deaths (1.81 vs 2.87 per 100 person-years), with an adjusted hazard ratio of 0.57 (95% confidence interval 0.52-0.62).Periodontal treatment for COPD patients could reduce the risk of adverse respiratory events and mortality. The adequate periodontal health care is important for COPD patients with periodontal diseases.


Assuntos
Doenças Periodontais/complicações , Doenças Periodontais/terapia , Pneumonia/epidemiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Insuficiência Respiratória/epidemiologia , Idoso , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Fatores de Proteção , Doença Pulmonar Obstrutiva Crônica/mortalidade , Curetagem Subgengival , Taiwan/epidemiologia
16.
Chem Commun (Camb) ; 51(30): 6617-20, 2015 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-25780804

RESUMO

A hydrothermal route to regulate the swelling and responsiveness properties of poly(N-isopropylacrylamide) (PNIPAM) hydrogels is reported. During the process, water is the only reactive medium used, and the hydrogel properties can be programmed effectively.


Assuntos
Hidrogéis/química , Temperatura , Acrilamidas/química , Resinas Acrílicas/química , Oxirredução
17.
Biomaterials ; 65: 76-85, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26142778

RESUMO

The capability to remotely control the release of biomolecules provides an unique opportunity to monitor and regulate neural signaling, which spans extraordinary spatial and temporal scales. While various strategies, including local perfusion, molecular "uncaging", or photosensitive polymeric materials, have been applied to achieve controlled releasing of neuro-active substances, it is still challenging to adopt these technologies in many experimental contexts that require a straightforward but versatile loading-releasing mechanism. Here, we develop a synthetic strategy for remotely controllable releasing of neuro-modulating molecules. This platform is based on microscale composite hydrogels that incorporate polypyrrole (PPy) nanoparticles as photo-thermal transducers and is triggered by near-infrared-light (NIR) irradiation. Specifically, we first demonstrate the utility of our technology by recapitulating the "turning assay" and "collapse assay", which involve localized treatment of chemotactic factors (e.g. Netrin or Semaphorin 3A) to subcellular neural elements and have been extensively used in studying axonal pathfinding. On a network scale, the photo-sensitive microgels are also validated for light-controlled releasing of neurotransmitters (e.g. glutamate). A single NIR-triggered release is sufficient to change the dynamics of a cultured hippocampal neuron network. Taking the advantage of NIR's capability to penetrate deep into live tissue, this technology is further shown to work similarly well in vivo, which is evidenced by synchronized spiking activity in response to NIR-triggered delivery of glutamate in rat auditory cortex, demonstrating remote control of brain activity without any genetic modifications. Notably, our nano-composite microgels are capable of delivering various molecules, ranging from small chemicals to large proteins, without involving any crosslinking chemistry. Such great versatility and ease-of-use will likely make our optically-controlled delivery technology a general and important tool in cell biology research.


Assuntos
Preparações de Ação Retardada/química , Hidrogéis/química , Nanopartículas/química , Neurônios/efeitos dos fármacos , Neurotransmissores/administração & dosagem , Polímeros/química , Pirróis/química , Animais , Células Cultivadas , Sistemas de Liberação de Medicamentos/instrumentação , Raios Infravermelhos , Nanopartículas/ultraestrutura , Neurônios/citologia , Ratos , Ratos Sprague-Dawley
18.
Health Phys ; 109(3): 242-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26222219

RESUMO

Acute radiation syndrome results from radiation exposure, such as in accidental nuclear disasters. Safe and effective radioprotectants, mitigators, and treatment drugs must be developed as medical countermeasures against radiation exposure. Here, the authors evaluated CCM-Ami, a novel polyethylene glycol micelle encapsulated with amifostine, for its radioprotective properties after total-body irradiation from a 60Co source. Male C57BL/6 mice (6-8 wk old) were intravenously injected with 45 mg kg(-1) of CCM-Ami 90 min before exposure to 7.2 and 8.5 Gy irradiation at a dose rate of 0.04 Gy min(-1). Both survival benefit and hematopoietic protection were observed after prophylactic CCM-Ami administration when compared with the effects measured in excipient control and amifostine groups. Pharmacokinetic results showed that after the intravenous injection, the plasma concentration of WR-1065, the active form of amifostine, was higher in CCM-Ami-treated mice than in amifostine-treated mice. These findings suggest that CCM-Ami-mediated hematopoietic protection plays a key role in enhancing survival of mice exposed to radiation toxicity and thus indicate that CCM-Ami is a radioprotectant that can be used safely and effectively in nuclear disasters.


Assuntos
Síndrome Aguda da Radiação/prevenção & controle , Amifostina/administração & dosagem , Protetores contra Radiação/administração & dosagem , Síndrome Aguda da Radiação/sangue , Amifostina/farmacocinética , Animais , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Masculino , Mercaptoetilaminas/sangue , Camundongos , Camundongos Endogâmicos C57BL , Micelas , Polietilenoglicóis , Protetores contra Radiação/farmacocinética , Irradiação Corporal Total
19.
Medicine (Baltimore) ; 94(46): e2047, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26579813

RESUMO

Several studies have reported an association between chronic obstructive pulmonary disease (COPD) and periodontal diseases. However, a large-scale population-based cohort study was previously absent from the literature. Therefore, we evaluated the risk of periodontal diseases in patients with COPD in a nationwide population.From the National Health Insurance claims data of Taiwan, we identified 22,332 patients with COPD who were newly diagnosed during 2000 to 2010. For each case, two individuals without COPD were randomly selected and frequency matched by age, sex, and diagnosis year. Both groups were followed up till the end of 2011.The overall incidence of periodontal diseases was 1.19-fold greater in the COPD group than in the comparison group (32.2 vs 26.4 per 1000 person-years; 95% confidence interval [CI] 1.15-1.24). Compared with non-COPD patients, the adjusted hazard ratios of patients with COPD increased with the number of emergency room visits (from 1.14 [95% CI 1.10-1.19] to 5.09 [95% CI 4.53-5.72]) and admissions (from 1.15 [95% CI 1.10-1.20] to 3.17 [95% CI 2.81-3.57]). In addition, the adjusted hazard ratios of patients with COPD treated with inhaled corticosteroids (1.22, 95% CI 1.11-1.34) and systemic corticosteroids (1.15, 95% CI 1.07-1.23) were significantly higher than those of patients not treated with corticosteroids.Patient with COPD are at a higher risk of developing periodontal diseases than the general population. Our results also support that the risk of periodontal diseases is proportional to COPD control. In addition, patients who receive corticosteroid treatment are at a higher risk of developing periodontal diseases.


Assuntos
Doenças Periodontais/etiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Doenças Periodontais/epidemiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Taiwan
20.
Chem Commun (Camb) ; 49(72): 7887-9, 2013 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-23903434

RESUMO

Poly(N-isopropylacrylamide) (pNIPAM) composite microgels incorporating polypyrrole (PPy) nanoparticles were produced using droplet microfluidics. The composite microgels exhibited site-specific de-swelling-swelling properties that were activated by near-infrared light. Their applications for programmable drug release by pulsed-light control were also demonstrated.


Assuntos
Géis/química , Luz , Microfluídica , Polímeros/química , Pirróis/química , Transdutores , Acrilamidas/química , Raios Infravermelhos , Nanopartículas/química , Polímeros/efeitos da radiação , Pirróis/efeitos da radiação , Temperatura
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