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1.
Acta Derm Venereol ; 102: adv00684, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35170741

RESUMO

Elastolytic giant cell granuloma, an idiopathic granulomatous dermatosis, is characterized by annular plaques on sun-exposed areas, and has been termed actinic granuloma or annular elastolytic giant cell granuloma. Many atypical clinical manifestations and lesions involving sun-protected areas have been reported. The aims of this retrospective study of 105 patients were to summarize the clinical and histological features of patients with this condition; to provide evidence for the viewpoint that elastolytic giant cell granuloma is a better term to include all clinical morphological types presenting with elastolysis, elastophagocytosis, and an infiltrate of multinucleated giant cells histologically; and to establish a new clinical classification. The varying clinical manifestations were further categorized into annular, papular, giant, mixed and generalized forms. The pathological manifestations were classified into giant cell, necrobiotic, histiocytic, sarcoidal and mixed patterns. Diabetes mellitus or impaired glucose tolerance were the most commonly identified comorbidities. Oral low-dose corticosteroid may be an effective treatment.


Assuntos
Diabetes Mellitus , Granuloma de Células Gigantes , Transtornos de Fotossensibilidade , Tecido Elástico/patologia , Granuloma/patologia , Granuloma de Células Gigantes/tratamento farmacológico , Granuloma de Células Gigantes/patologia , Humanos , Transtornos de Fotossensibilidade/patologia , Estudos Retrospectivos
2.
Proc Natl Acad Sci U S A ; 116(20): 9820-9824, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31036653

RESUMO

Middle to Late Pleistocene human evolution in East Asia has remained controversial regarding the extent of morphological continuity through archaic humans and to modern humans. Newly found ∼300,000-y-old human remains from Hualongdong (HLD), China, including a largely complete skull (HLD 6), share East Asian Middle Pleistocene (MPl) human traits of a low vault with a frontal keel (but no parietal sagittal keel or angular torus), a low and wide nasal aperture, a pronounced supraorbital torus (especially medially), a nonlevel nasal floor, and small or absent third molars. It lacks a malar incisure but has a large superior medial pterygoid tubercle. HLD 6 also exhibits a relatively flat superior face, a more vertical mandibular symphysis, a pronounced mental trigone, and simple occlusal morphology, foreshadowing modern human morphology. The HLD human fossils thus variably resemble other later MPl East Asian remains, but add to the overall variation in the sample. Their configurations, with those of other Middle and early Late Pleistocene East Asian remains, support archaic human regional continuity and provide a background to the subsequent archaic-to-modern human transition in the region.


Assuntos
Fósseis , Crânio , China , Humanos , Dente
3.
Angew Chem Int Ed Engl ; 58(17): 5577-5581, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30838761

RESUMO

Tracking membrane-interacting molecules and visualizing their conformational dynamics are key to understanding their functions. It is, however, challenging to accurately probe the positions of a molecule relative to a membrane. Herein, a single-molecule method, termed LipoFRET, is reported to assess interplay between molecules and liposomes. It takes advantage of FRET between a single fluorophore attached to a biomolecule and many quenchers in a liposome. This method was used to characterize interactions between α-synuclein (α-syn) and membranes. These results revealed that the N-terminus of α-syn inserts into the membrane and spontaneously transitions between different depths. In contrast, the C-terminal tail of α-syn is regulated by calcium ions and floats in solution in two conformations. LipoFRET is a powerful tool to investigate membrane-interacting biomolecules with sub-nanometer precision at the single-molecule level.


Assuntos
Lipossomos/metabolismo , Lipídeos de Membrana/metabolismo , Nanotecnologia/métodos , Humanos
4.
J Acoust Soc Am ; 140(6): EL534, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28039994

RESUMO

The gentamicin-loaded nano-sized liposomes are shown to penetrate into alginate-based Ralstonia insidiosa bacterial biofilms by acoustic streaming generated by moderate pulsed ultrasound (frequency = 2.25 MHz, 10% duty cycle and spatially and temporally averaged intensity, ISATA ≈ 4.4 W/cm2). The liposomes are then burst by the scanned relatively high intensity ultrasound (frequency = 1.1 MHz, 10% duty cycle, the spatially and temporally averaged intensity ISATA ≈ 90 W/cm2) in situ, and the gentamicin solution is released from the liposomes resulting in 72% of Ralstonia insidiosa killing.


Assuntos
Biofilmes , Gentamicinas , Lipossomos , Ralstonia , Ondas Ultrassônicas
5.
J Mater Sci Mater Med ; 26(9): 234, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26395359

RESUMO

Bioreducible polymers have appeared as the ideal drug carriers for tumor therapy due to their properties of high stability in extracellular circulation and rapid drug release in intracellular reducing environment. Recently, the diselenide bond has emerged as a new reduction-sensitive linkage. In this work, the amphiphilic poly(ethylene glycol)-b-poly(L-lactide) containing diselenide bond has been synthesized and used to load anti-tumor drug, docetaxel (DTX), to form the redox micelles. It was found that the redox micelles showed a rapid response to glutataione (GSH), which resulted in a fast release of DTX in the presence of GSH. In contrast, <40 % of DTX was released from the micelles within 72 h under the normal condition (absence of GSH). The DTX-loaded redox micelles showed the significant inhibition effect to MCF-7 cells, and the cytotoxicity was dependent on the intracellular GSH concentrations. Moreover, considering the potentially clinical applications of the micelles through intravenous injection, the blood compatibility was also studied by the hemolysis analysis, activated partial thromboplastin time, prothrombin time and thromboelastography assays. These results confirmed that the redox micelles showed good blood safety, suggesting a potential application in tumor therapy.


Assuntos
Sistemas de Liberação de Medicamentos , Micelas , Poliésteres/química , Polietilenoglicóis/química , Selênio/química , Glutationa/metabolismo , Hemólise , Humanos , Células MCF-7 , Oxirredução
6.
J Acoust Soc Am ; 138(2): 1043-51, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26328720

RESUMO

Because biofilms have resistance to antibiotics, their control using minimum amounts of chemicals and energy becomes a critical issue particularly for resource-constrained long-term space and deep-sea explorations. This preliminary study investigates how ultrasound promoting penetration of antibiotic-loaded liposomes into alginate-based bacterial biofilms, resulting in enhanced bacterial (Ralstonia insidiosa) killing. Nano-sized liposomes are used as a delivery vehicle for the antibiotic gentamicin. Alginate-based synthetic biofilms, which are widely acknowledged as biofilm phantoms, filled with liposome solution are formed at the bottoms of six-well Petri dishes and exposed to ultrasound (frequency = 2.25 MHz, 10% duty cycle, and spatially and temporally averaged intensity ISAPA = 4.4 W/cm(2)). Gentamicin is released from liposomes after they are lysed using detergent solution (0.05% sodium dodecyl sulfate, 1.0% Triton X-100) and incubated for 20 min. The alginate biofilm is dissolved and diluted, counting of colony-forming units shows about 80% of the bacteria are killed. It has also been shown the liposome-capture density by the alginate film increases linearly with the ultrasound intensity up to ISAPA = 6.2 W/cm(2) reaching approximately threefold that without ultrasound. Measurement by using particle-image velocimetry has demonstrated the acoustic streaming with modification by thermal convection controls the enhancement of the liposome capture rate.


Assuntos
Antibacterianos/administração & dosagem , Biofilmes , Desinfecção/métodos , Gentamicinas/administração & dosagem , Lipossomos , Ondas Ultrassônicas , Purificação da Água/métodos , Alginatos , Carga Bacteriana , Portadores de Fármacos , Fluoresceína-5-Isotiocianato/análise , Ácido Glucurônico , Ácidos Hexurônicos , Temperatura Alta , Hidrogéis , Fluxometria por Laser-Doppler , Ralstonia/efeitos dos fármacos
7.
J Mater Sci Mater Med ; 25(6): 1461-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24652594

RESUMO

Molecularly imprinted poly(hydroxyethyl methacrylate) microspheres (PHEMA MIPMs) were prepared via precipitation polymerization in this article, using gatifloxacin (GFLX), hydroxyethyl methacrylate (HEMA), and ethylene glycol dimethacrylate (EGDMA) as template molecule, functional monomer and cross-linker, respectively. The effects of reaction medium, initial total monomers, cross-linker and molecular imprinting on the polymerization were investigated systematically. The interaction between GFLX and HEMA in pre-solution was studied by UV-Visible spectrophotometer, both size and morphology of products were characterized by a scanning electron microscope. When the total initial monomer concentration was 1 vol%, EGDMA content was 70 mol%, a group of uniform PHEMA MIPMs were prepared at different GFLX/MAA molar ratios, with diameter range from 2.06 ± 0.07 to 2.82 ± 0.20 µm. The results of drug loading and in vitro release experiments demonstrated that PHEMA MIPMs could achieve a higher GFLX loading content and a more acceptable sustained release than non-imprinted ones.


Assuntos
Acrilatos/química , Cápsulas/síntese química , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Fluoroquinolonas/administração & dosagem , Fluoroquinolonas/química , Impressão Molecular/métodos , Polímeros/química , Antibacterianos/administração & dosagem , Antibacterianos/síntese química , Cápsulas/administração & dosagem , Difusão , Gatifloxacina , Teste de Materiais , Tamanho da Partícula , Propriedades de Superfície
8.
Environ Technol ; 35(21-24): 2821-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25176486

RESUMO

The effect of C/N ratio on extracellular polymeric substances (EPS) of activated sludge was investigated in an anoxic-aerobic sequencing batch reactor (SBR) treating saline wastewater. The protein (PN) and protein/polysaccharide (PN/PS) ratio in the loosely bound EPS (LB-EPS) increased with the decrease of C/N ratio, whereas the PS in the LB-EPS decreased. The PS, PN and PN/PS ratio in the tightly bound EPS (TB-EPS) were independent of C/N ratio. Two fluorescence peaks in the LB-EPS and TB-EPS were identified at excitation/emission (Ex/Em) wavelengths of 275-280/335-340 nm and 220-225/330-340 nm by three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, respectively. These peaks in LB-EPS and TB-EPS were, respectively, associated with tryptophan protein-like substances and aromatic protein-like substances. The tryptophan protein-like fluorescence peaks in LB-EPS showed blue shift along the Ex axis and red shift along the Em axis with the decrease of C/N ratio. Fourier transform infrared spectra suggested that the variation of C/N ratio had more distinct effect on the functional groups of protein in the LB-EPS than those in the TB-EPS. The sludge volume index value decreased with the increase of LB-EPS, but there was no correlation between SVI and TB-EPS.


Assuntos
Biopolímeros/análise , Reatores Biológicos , Polissacarídeos/análise , Proteínas/análise , Esgotos , Aerobiose , Anaerobiose , Carbono/análise , Nitrogênio/análise , Salinidade , Águas Residuárias
9.
Acta Biomater ; 182: 171-187, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38759743

RESUMO

Photodamage is one of the most common causes of skin injury. High molecular weight hyaluronic acid (HHA) has shown immense potential in the treatment of skin photodamage by virtue of its anti-inflammatory, reparative, and antioxidative properties. However, due to its large molecular structure of HHA, HHA solution could only form a protective film on the skin surface in conventional application, failing to effectively penetrate the skin, which necessitates the development of new delivery strategies. Liposomes, with a structure similar to biological membranes, have garnered extensive attention as transdermal drug delivery carriers because of their advantages in permeability, dermal compatibility, and biosafety. Herein, we have developed a HHA-liposome transdermal system (HHL) by embedding HHA into the liposome structure using reverse evaporation, high-speed homogenization, and micro-jet techniques. The effective penetration and long-term residence of HHA in skin tissue were multidimensionally verified, and the kinetics of HHA in the skin were extensively studied. Moreover, it was demonstrated that HHL significantly strengthened the activity of human keratinocytes and effectively inhibits photo-induced cellular aging in vitro. Furthermore, a murine model of acute skin injury induced by laser ablation was established, where the transdermal system showed significant anti-inflammatory and immunosuppressive properties, promoting skin proliferation and scar repair, thereby demonstrating immense potential in accelerating skin wound healing. Meanwhile, HHL significantly ameliorated skin barrier dysfunction caused by simulated sunlight exposure, inhibited skin erythema, inflammatory responses, and oxidative stress, and promoted collagen expression in a chronic photodamage skin model. Therefore, this transdermal delivery system with biocompatibility represents a promising new strategy for the non-invasive application of HHA in skin photodamage, revealing the significant potential for clinical translation and broad application prospects. STATEMENT OF SIGNIFICANCE: The transdermal system utilizing hyaluronic acid-based liposomes enhances skin permeability and retains high molecular weight hyaluronic acid (HHL). In vitro experiments with human keratinocytes demonstrate significant skin repair effects of HHL and its effective inhibition of cellular aging. In an acute photodamage model, HHL exhibits stronger anti-inflammatory and immunosuppressive properties, promoting skin proliferation and scar repair. In a chronic photodamage model, HHL significantly improves skin barrier dysfunction, reduces oxidative stress induced by simulated sunlight, and enhances collagen expression.


Assuntos
Administração Cutânea , Ácido Hialurônico , Lipossomos , Envelhecimento da Pele , Pele , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Lipossomos/química , Animais , Humanos , Pele/patologia , Pele/efeitos dos fármacos , Pele/metabolismo , Envelhecimento da Pele/efeitos dos fármacos , Camundongos , Peso Molecular , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Sistemas de Liberação de Medicamentos , Células HaCaT
10.
Colloids Surf B Biointerfaces ; 223: 113146, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36696824

RESUMO

CRISPR-Cas9 technology has been proven to be the most straightforward and accurate tool for gene therapy, but some limitations, such as the inefficient transfection or inability to precisely target, prevent the gene therapy from achieving the desired therapeutic effect. To overcome these, a kind of glutathione-sensitive cationic vectors, hyperbranched polyamide amine (HPAA) was designed for Delivery of CRISPR-Cas9 RNA plasmid, and the cyclic RGD (Arg-Gly-Asp) was conjugated for the targeted treatment of nasopharyngeal carcinoma (NPC). Disulfide bonds in HPAA segments can specifically respond to the high glutathione concentration in the tumor microenvironment. Meanwhile, RGD could especially interact to the integrin αvß3 receptors which are highly expressed on the surface of NPC tumor cells. The results showed that more HPAA-RGD/SGK3-gRNA complexes could be uptaken by NPC HNE-1 cells after RGD was conjugated, and then the plasmid could be accumulated in the NPC tumor as well, which may assure the satisfied NPC therapy effect in vivo. In transfection assays, this complex showed the acceptable gene transfection efficiency in vitro and the obvious tumor inhibition effect in vivo, suggested a potential application in gene therapy to NPC.


Assuntos
Sistemas CRISPR-Cas , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/terapia , Polímeros , Terapia Genética/métodos , Plasmídeos , Glutationa , Oligopeptídeos/química , RNA Interferente Pequeno/genética , Aminas/química , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/terapia , Microambiente Tumoral
11.
Adv Healthc Mater ; 12(1): e2200807, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36177664

RESUMO

Since the first surgery 50 years ago, cochlear implantation (CI) is the major treatment for patients with severe sensorineural hearing loss. However, unexpected foreign body reactions (FBRs) after surgery are reported in 90% of CI recipients, resulting in the formation of fibrosis in the cochlea and progressive residual hearing loss. Zwitterion modification is universally used to reduce bio-fouling and suppress FBRs but never for CI. In the present study, a zwitterionic coating is developed, which is composed of poly sulfobetaine methacrylate (PSB) and polydopamine (PDA) for cochlear implants. The PSB-PDA coating shows a series of characters for an ideal anti-FBRs material, including super-hydrophilicity, low protein and cell adsorption, long-term stability, and high biocompatibility. Compared to the uncoated controls, PSB-PDA coating inhibits the activation of macrophages and reduces the release of inflammatory factors (TNF-α, IL-1ß, NO) and fibrosis-related factors (TGF-ß1, α-SMA, collagen I). PSB-PDA coated electrode arrays suppress fibrosis completely and preserve residual hearing significantly in rat CI models. These results suggest that PSB-PDA coating is a novel strategy for anti-fibrosis to improve the outcomes of CI.


Assuntos
Implante Coclear , Implantes Cocleares , Perda Auditiva , Ratos , Animais , Implante Coclear/efeitos adversos , Perda Auditiva/etiologia , Implantes Cocleares/efeitos adversos , Polímeros/farmacologia
12.
Adv Sci (Weinh) ; 10(11): e2206959, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36793143

RESUMO

Polymeric systems that provide cationic charges or biocide-release therapeutics are used to treat the bacteria-infected wound. However, most antibacterial polymers based on topologies with restricted molecular dynamics still do not satisfy the clinical requirements due to their limited antibacterial efficacy at safe concentrations in vivo. Here a NO-releasing topological supramolecular nanocarrier with rotatable and slidable molecular entities is reported to provide conformational freedom to promote the interactions between the carrier and the pathogenic microbes, hence greatly improving the antibacterial performance. With improved contacting-killing and efficient delivery of NO biocide from the molecularly dynamic cationic ligand design, the NO-loaded topological nanocarrier achieves excellent antibacterial and anti-biofilm effects via destroying the bacterial membrane and DNA. MRSA-infected rat model is also brought out to demonstrate its wound-healing effect with neglectable toxicity in vivo. Introducing flexible molecular motions into therapeutic polymeric systems is a general design to enhance the healing of a range of diseases.


Assuntos
Óxido Nítrico , Cicatrização , Ratos , Animais , Óxido Nítrico/farmacologia , Bactérias , Polímeros/farmacologia , Antibacterianos/farmacologia
13.
Genes (Basel) ; 13(10)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36292591

RESUMO

A complex molecular regulatory network plays an important role in the development and ripening of fruits and leads to significant differences in apparent characteristics. Comparative transcriptome and sRNAome analyses were performed to reveal the regulatory mechanisms of fruit ripening in a spontaneous early-ripening navel orange mutant ('Ganqi 4', Citrus sinensis L. Osbeck) and its wild type ('Newhall' navel orange) in this study. At the transcript level, a total of 10792 genes were found to be differentially expressed between MT and WT at the four fruit development stages by RNA-Seq. Additionally, a total of 441 differentially expressed miRNAs were found in the four periods, and some of them belong to 15 families. An integrative analysis of the transcriptome and sRNAome data revealed some factors that regulate the mechanisms of formation of early-ripening traits. First, secondary metabolic materials, especially endogenous hormones, carotenoids, cellulose and pectin, obviously changed during fruit ripening in MT and WT. Second, we found a large number of differentially expressed genes (PP2C, SnRK, JAZ, ARF, PG, and PE) involved in plant hormone signal transduction and starch and sucrose metabolism, which suggests the importance of these metabolic pathways during fruit ripening. Third, the expression patterns of several key miRNAs and their target genes during citrus fruit development and ripening stages were examined. csi-miR156, csi-miR160, csi-miR397, csi-miR3954, and miRN106 suppressed specific transcription factors (SPLs, ARFs, NACs, LACs, and TCPs) that are thought to be important regulators involved in citrus fruit development and ripening. In the present study, we analyzed ripening-related regulatory factors from multiple perspectives and provide new insights into the molecular mechanisms that operate in the early-ripening navel orange mutant 'Ganqi 4'.


Assuntos
Citrus sinensis , MicroRNAs , Citrus sinensis/genética , Transcriptoma/genética , Frutas , Reguladores de Crescimento de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Carotenoides/metabolismo , Sacarose/metabolismo , Pectinas/metabolismo , Amido/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Hormônios , Celulose/metabolismo
14.
Biomacromolecules ; 12(9): 3124-30, 2011 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-21780829

RESUMO

A polymeric prodrug, PEGylated indomethacin (MPEG-indo), was prepared and then used to interact with α-cyclodextrin (α-CD) in their aqueous mixed system. This process could lead to the formation of supramolecular hydrogel under mild conditions and simultaneous encapsulation of MPEG-indo in the hydrogel matrix. For the formed supramolecular hydrogel, its gelation kinetics, mechanical strength, shear-thinning behavior and thixotropic response were investigated with respect to the effects of MPEG-indo and α-CD amounts by dynamic and steady rheological tests. Meanwhile, the possibility of using this hydrogel matrix as injectable drug delivery system was also explored. By in vitro release and cell viability tests, it was found that the encapsulated MPEG-indo could exhibit a controlled and sustained release behavior as well as maintain its biological activity.


Assuntos
Preparações de Ação Retardada/síntese química , Portadores de Fármacos/síntese química , Indometacina/metabolismo , Polietilenoglicóis/química , Polímeros/química , Pró-Fármacos/síntese química , alfa-Ciclodextrinas/química , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/metabolismo , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/metabolismo , Portadores de Fármacos/farmacologia , Células Hep G2 , Humanos , Indometacina/química , Cinética , Espectroscopia de Ressonância Magnética , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Resistência ao Cisalhamento , Viscosidade , Água
15.
Drug Deliv ; 28(1): 1673-1684, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34347538

RESUMO

With dexamethasone as the model drug and polycaprolactone (PCL) as the carrier material, a drug delivery coating for cochlear electrodes was prepared, to control cochlear fibrosis caused by cochlear implantation. A dexamethasone/poly (ε-caprolactone)-based electrode coating was prepared using the impregnation coating method. Preparation parameters were optimized, yielding 1 impregnation instance, impregnation time of 10 s, and PCL concentration of 10%. The coating was characterized in vitro using scanning electron microscopy, a universal machine, high-performance liquid chromatography, and CCK-8. The surface was porous and uniformly thick (average thickness, 48.67 µm)-with good flexibility, long-term slow drug release, and optimal drug concentration-and was biologically safe. The experimental results show that PCL is an ideal controlled-release material for dexamethasone as a drug carrier coating for cochlear implants.


Assuntos
Anti-Inflamatórios/administração & dosagem , Implantes Cocleares , Dexametasona/administração & dosagem , Fibrose/prevenção & controle , Poliésteres/química , Animais , Anti-Inflamatórios/farmacologia , Materiais Biocompatíveis , Preparações de Ação Retardada , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Porosidade , Ratos , Propriedades de Superfície
16.
ACS Appl Mater Interfaces ; 13(48): 57009-57022, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34806877

RESUMO

Photodynamic therapy (PDT) has attracted extensive attention in the clinical treatment of malignant tumor. However, the acidic and hypoxic conditions of the tumor microenvironment (TME) limit the further application of PDT in the clinic. Herein, we fabricate a new nanoplatform─HPDA@MnO2@Ce6/DOX@PEG-RGD (HPMRCD)─by means of coating hollow polydopamine nanoparticles (HPDA) with manganese dioxide (MnO2), which is modified by cyclic RGD functionalized poly(ethylene glycol) (PEG) and further co-loaded with a photosensitizer, Chlorin e6 (Ce6), and a chemotherapy drug, doxorubicin (DOX). This nanoplatform could be enriched in tumor tissues, then instantly dissociated under an acidic and H2O2-rich TME. The dual-responsive release of Mn2+ ions and oxygen (O2) can relieve tumor hypoxia, which can be used as a magnetic resonance contrast agent and the latter can enhance the PDT effect. Furthermore, the degradation of HPMRCD leads to an efficient loaded therapeutic molecule release, thus yielding a potential therapy to enhance tumor suppression by adopting the combined chemo-photodynamic therapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Materiais Biomiméticos/farmacologia , Doxorrubicina/farmacologia , Nanopartículas/química , Oxigênio/farmacologia , Fotoquimioterapia , Hipóxia Tumoral/efeitos dos fármacos , Animais , Antibióticos Antineoplásicos/química , Apoptose/efeitos dos fármacos , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Indóis/química , Indóis/farmacologia , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Teste de Materiais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Óxidos/química , Óxidos/farmacologia , Oxigênio/química , Tamanho da Partícula , Polímeros/química , Polímeros/farmacologia , Porosidade
17.
Front Surg ; 8: 747304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778361

RESUMO

Background: An iatrogenic bile duct injury (IBDI) is a severe complication that has a great impact on the physical and mental quality of life of the patients, especially for patients with postoperative benign biliary stricture. The effective measures for end-to-end biliary-to-biliary anastomosis intraoperative are essential to prevent the postoperative bile duct stricture, but also a challenge even to the most skilled biliary tract surgeon. Objective: A postoperative benign biliary stricture is an extremely intractable complication that occurs following IBDI. This study aimed to introduce a novel end-to-end biliary-to-biliary anastomosis technique named fish-mouth-shaped (FMS) end-to-end biliary-to-biliary reconstruction and determine the safety and effectiveness for preventing the postoperative benign biliary stricture in both rats and humans. Methods: In this study, 18 patients with biliary injury who underwent an FMS reconstruction procedure were retrospectively analyzed. Their general information, disease of the first hospitalization, operation method, and classification of bile duct injury (BDI) were collected. The postoperative complications were evaluated immediately perioperatively and the long-term complications were followed up at the later period of at least 5 years. An IBDI animal model using 18 male rats was developed for animal-based evaluations. A bile duct diathermy injury model was used to mimic BDI. The FMS group underwent an FMS reconstruction procedure while the control group underwent common end-to-end biliary-to-biliary anastomosis, a sham operation group was also established. The blood samples, liver, spleen, and common bile duct tissues were harvested for further assessments. Results: In the retrospective study, there was no postoperative mortality and no patient developed cholangitis during the 5-years postoperation follow-up. In the study of IBDI animal models, compared with the control group, the FMS reconstruction procedure reduced the occurrence of benign biliary stenosis, liver function damage, and jaundice. The blood tests as well as morphological and pathological observations revealed that rats in the FMS reconstruction group had a better recovery than those in the control group. Conclusions: An FMS reconstruction procedure is a safe and efficient BDI treatment method.

18.
J Biomed Nanotechnol ; 17(1): 18-36, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33653494

RESUMO

Multidrug resistance (MDR) is a key to the ineffectiveness of hepatocellular carcinoma (HCC) chemotherapy. Oxaliplatin (OXA), as one of the first-line chemotherapeutic drugs for HCC, abnormally activates the PI3K/AKT/mTOR signaling pathway and DNA damage repair pathway (NHEJ and HR), causing drug resistance and consequnet compromised efficacy. Herein, we developed a hollow polydopamine nanoparticle (H-PDA)-based nano-delivery system (O/P-HP) that contained OXA and a dual PI3K/mTOR inhibitor PKI-587 with complementary effects for combating drug resistance in cancer chemotherapy. The hollow structure of H-PDA endowed O/P-HP with high loading efficiencies of OXA and PKI-587-up to 49.6% and 7.0%, respectively. In addition, benefiting from the intracellular delivery of H-PDA as well as the highly concentrated drugs therein, O/P-HP inhibited the proliferation of OXA-resistant HR cells, resulting in a cell viability of only 17.63%. These values were significantly superior to those with OXA single-agent treatment and treatment with free OXA in combination with PKI-587. We examined the intrinsic mechanisms of the combination therapy: O/PHP had excellent anti-cancer effects via the simultaneous upstream and downstream action to re-sensitize HR cells to chemotherapy; OXA induced strong apoptosis via the direct platinum lesions on DNA molecules, while PKI-587 normalized the abnormally activated PI3K/AKT/mTOR signaling pathway and DNA damage repair pathway (NHEJ and HR) that could attenuate the effectiveness of OXA, thus resulting in inhibition of cell proliferation, migration and DNA repair enzyme activity and the augment of apoptotic effects. Such combination therapy, with simultaneous upstream and downstream action, may be a strategy for minimizing resistance for anti-cancer treatments.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Preparações Farmacêuticas , Apoptose , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Indóis , Neoplasias Hepáticas/tratamento farmacológico , Morfolinas , Oxaliplatina , Fosfatidilinositol 3-Quinases , Polímeros , Triazinas
19.
Biomacromolecules ; 11(9): 2204-12, 2010 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-20831271

RESUMO

Heparin, a powerful anticoagulant used for the prophylaxis of both surgical and medical thrombosis, was covalently incorporated into a supramolecular hydrogel network. For this attempt, heparin was first conjugated with amino-terminated poly(ethylene glycol) methyl ether by carbodiimide chemistry and then used to interact with α-cyclodextrin in aqueous solution. The rheological measurements and X-ray diffraction analyses were used to characterize the hydrogel formation. It was found that the gelation kinetics and hydrogel properties could be modulated by changing the amount of conjugated heparin or α-cyclodextrin. By circular dichroism analyses and in vitro release experiments, resultant hydrogel material was found to have a great potential as an injectable matrix for the encapsulation and sustained release of model protein drug (bovine serum albumin). By in vitro release, blood clotting, and hemolysis experiments, such a supramolecular hydrogel was also confirmed to have a controlled release profile for conjugated heparin and shows good anticoagulant and blood-compatible properties.


Assuntos
Sistemas de Liberação de Medicamentos , Heparina/química , Heparina/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Polietilenoglicóis/química , alfa-Ciclodextrinas/química , Animais , Anticoagulantes/química , Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Bovinos , Dicroísmo Circular , Preparações de Ação Retardada , Portadores de Fármacos , Hemólise/efeitos dos fármacos , Heparina/administração & dosagem , Humanos , Cinética , Espectroscopia de Ressonância Magnética , Soroalbumina Bovina/metabolismo , Difração de Raios X
20.
Tissue Eng Regen Med ; 17(5): 705-715, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32588341

RESUMO

BACKGROUND: Beta-tricalcium phosphate (ß-TCP) has been employed successfully as a synthetic graft material in maxillary sinus floor augmentation (MSFA) for placing dental implants. However, the lack of osteogenic and osteoinductive properties of this substitute invariably results in bone regeneration of low quality and quantity. The purpose of this study was to determine whether loading dentin matrix protein-1 (DMP1) gene-modified bone marrow mesenchymal stem cells (BMSCs) onto ß-TCP promoted bone regeneration and osteointegration of dental implants in MSFA of dogs. METHODS: BMSCs were transduced with a lentiviral vector overexpressing the DMP1 gene (Lenti-DMP1) and with a lentiviral vector overexpressing enhanced green fluorescent protein (Lenti-EGFP) in vitro and were loaded into ß-TCP scaffolds for autologous sinus grafting. Beagles received bilateral MSFA with four biomaterials (① Lenti-DMP1-transduced BMSCs/ß-TCP, ② Lenti-EGFP-transduced BMSCs/ß-TCP, ③ BMSCs/ß-TCP, ④ ß-TCP) and simultaneous implant placement at each sinus. Twelve weeks post operation, the maxillae were explanted, and every sinus was evaluated by radiographic observation, micro-CT and histological analysis. The osteogenic outcomes of bone regeneration and osseointegration were compared between the four groups. RESULTS: The sinuses grafted with Lenti-DMP1-transduced BMSCs/ß-TCP constructs presented a significantly higher increase in compact radiopaque area, higher local bone mineral densities, greater bone-implant contact and greater bone density when compared to other three groups. CONCLUSION: These results demonstrated that combinations of ß-TCP and DMP1 gene-modified BMSCs could be used to construct tissue-engineered bone to enhance mineralization of the regenerated bone and osseointegration of dental implants in MSFA.


Assuntos
Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Animais , Células da Medula Óssea , Dentina , Cães , Maxila/diagnóstico por imagem , Maxila/cirurgia , Seio Maxilar , Osseointegração
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