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1.
Biomaterials ; 232: 119738, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31901695

RESUMO

In recent years, research trend has gradually removed from a concentration on monotherapy to combination therapy for fighting cancer. Combination photo-chemotherapy, including photodynamic-chemotherapy, photothermal-chemotherapy, as well as photodynamic-photothermal-chemotherapy, has demonstrated the priorities to elevate cancer therapeutic efficacies and diminish undesired side effects through different mechanisms in cancer treatment. In this review, we summarize the most recent progress in designing mesoporous silica-based nanoplatforms for combination delivery of multiple therapeutic agents, and discuss the treatment outcome in cancer by combining photodynamic therapy (PDT) and/or photothermal therapy (PTT) with chemotherapy. Furthermore, we highlight the drawbacks and challenges of employing mesoporous silica-based combinational formulations for effective cancer photo-chemotherapy, which might provide new guidelines for development of photo-chemo combination cancer treatments.

2.
Chem Commun (Camb) ; 55(11): 1659-1662, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30657473

RESUMO

A novel aligned nanofiber matrix was obtained from the self-assembly of an oligopeptide amphiphile. The alignment properties can be applied to measure residual dipolar couplings (RDCs) for the structural elucidation of molecules by liquid-state NMR.


Assuntos
Nanofibras/química , Oligopeptídeos/química , Microscopia Eletrônica de Transmissão , Ressonância Magnética Nuclear Biomolecular , Espalhamento a Baixo Ângulo , Temperatura Ambiente , Difração de Raios X
3.
Small ; 14(45): e1802417, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30247806

RESUMO

Efficacy and safety of chemotherapeutic drugs constitute two major criteria in tumor chemotherapy. Nanomedicines with tumor-targeted properties hold great promise for improving the efficacy and safety. To design targeted nanomedicines, the pathological characteristics of tumors are extensively and deeply excavated. Here, the rationale, principles, and advantages of exploiting these pathological characteristics to develop targeted nanoplatforms for tumor chemotherapy are discussed. Homotypic targeting with the ability of self-recognition to source tumors is reviewed individually. In the meanwhile, the limitations and perspective of these targeted nanomedicines are also discussed.


Assuntos
Nanomedicina/métodos , Animais , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Humanos , Neoplasias/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos
4.
Biomaterials ; 171: 178-197, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29698868

RESUMO

The clinical outcomes of conventional mono-chemotherapy of cancers are usually far from satisfactory due to some issues such as tumor heterogeneity and resistance to chemotherapeutic drugs. With the increasing knowledge of molecular signal pathways and pathological mechanisms involved in the initiation and progression of cancers, collaborative strategies have been elaborated to optimize therapeutic outcomes. This review surveys the most recent advances in combination therapy including combination chemotherapy, chemotherapy plus gene therapy, chemotherapy plus phototherapy, as well as chemotherapy plus immunotherapy. Additionally, chemotherapy-involved multiple therapy that merges various therapeutic modalities is also presented. We try to elicit the rationales of applying these combinational formulations for cancer chemotherapy, which might provide new guidelines for high-performance cancer treatments.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Terapia Combinada , Terapia Genética , Humanos , Imunoterapia , Neoplasias/imunologia , Fototerapia
5.
Colloids Surf B Biointerfaces ; 165: 345-354, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29518683

RESUMO

The morphology of nanomedicines has a large influence on the anticancer efficiency of therapeutic agents in biological systems. In this study, camptothecin (CPT)-based nanodrugs with helical and spherical shapes were simply built without the need of any additional carriers. Self-deliverable spherical nanodrug represented a therapeutic advantage over the helical one, which was uncovered from the in vitro toxicity assay. Confocal imaging study indicated that the better outcome of spherical nanodrug was ascribed to the faster cellular uptake. With the aid of sonication treatment, helical nanodrugs with different lengths (HD-1, HD-2, HD-3, HD-4) were created. In comparing with the longest HD-1, the drug release kinetics indicated that the shortest HD-4 exhibited a 20% elevation in cumulative drug release at the first 10 h. The internalized drug amount of HD-4 was three-fold higher than that of HD-1 after the cultivation with 4T1 cells for 2 h. These results demonstrated that the anticancer efficacy of helical nanodrugs was inversely proportional to their lengths. The strategy demonstrated here presents great promise for the preparation of nanodrugs with suitable morphology for cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Camptotecina/farmacologia , Nanomedicina/métodos , Nanopartículas/química , Animais , Antineoplásicos Fitogênicos/química , Camptotecina/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Liberação Controlada de Fármacos , Endocitose/fisiologia , Células HeLa , Humanos , Cinética , Camundongos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Sonicação
6.
Biomaterials ; 112: 234-247, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27768976

RESUMO

Carrier-assistant drug delivery systems (DDSs) have been rapidly established for cancer therapy and great strides have been made in recent years. However, further development of DDSs is retarded by the aspects such as the low drug carrying capacity, carrier-induced toxicity and immunogenicity, complex synthesis manipulation. Drug self-delivery systems (DSDSs), in which active drugs exhibit nanoscale characteristic to realize intracellular delivery by themselves without the help of nanocarriers, have been rapidly developed to address these issues. In this review, we present a comprehensive summary of the recent advances in DSDSs for cancer therapy. After a brief introduction to the major types of DSDSs and their fabrication strategies, we emphatically discuss some representative achievements of these DSDSs for passive or/and positive targeting therapy, combinational therapy as well as theranostics. The design principle is explained and justified, which can cast a new light on developing drug delivery systems for cancer treatments.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Desenho de Drogas , Nanocápsulas/administração & dosagem , Nanocápsulas/química , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Humanos , Neoplasias/metabolismo
7.
ACS Appl Mater Interfaces ; 9(3): 2093-2103, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28032742

RESUMO

A tumor targeting redox-responsive drug delivery system (DDS) with bioactive surface was constructed by immobilizing peptide-based amphiphile C12-CGRKKRRQRRRPPQRGDS (defined as ADDA-TCPP) onto the mesoporous silica nanoparticles (MSNs) as an end-capping nanovalve, which consists of two main segments: a hydrophobic alkyl chain ADDA and a hydrophilic amino acid sequence containing a Tat48-60 peptide sequence with a thiol terminal group and an RGDS targeting ligand, via a disulfide linkage for redox-triggered intracellular drug delivery. A series of characterizations confirmed that the nanosystem had been successfully fabricated. The antitumor drug doxorubicin (DOX) was selected as a model drug and efficiently trapped in the pores of MSNs, and an in vitro release experiment demonstrated that the mesopores of the resulting DOX-loaded MSNs (DOX@MSN-ss-ADDA-TCPP) could be sealed tightly with ADDA-TCPP self-assemblies through hydrophobic interactions between the alkyl chains; the resulting DDS exhibited "zero premature release" of DOX in the physical environment. However, a burst drug release was triggered by a high concentration of glutathione (GSH) in simulated cellular cytosol. Moreover, detailed investigations confirmed that incorporation of RGDS peptide facilitated the active targeting delivery of DOX to αvß3 integrin overexpressed tumor cells, and Tat48-60 modification on MSNs could enhance intracellular drug delivery, exhibiting an obvious toxicity to tumor cells. The multifunctional nanosystem constructed here can realize the controlled drug release and serve as a platform for designing multifunctional nanocarriers using diversified bioactive peptide-based amphiphile.


Assuntos
Nanopartículas , Doxorrubicina , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Peptídeos , Porosidade , Dióxido de Silício
8.
Carbohydr Polym ; 144: 238-44, 2016 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-27083814

RESUMO

A novel cationic flocculant of konjac glucomannan-graft-poly-(2-methacryloyloxyethyl)trimethyl ammonium chloride (KGM-g-PDMC), was successfully synthesized by using acidic ammonium cerium (IV) nitrate (CAN) as initiator in homogeneous aqueous solution. The graft copolymer was characterized using Fourier-transform infrared (FT-IR) spectroscopy, (1)H nuclear magnetic resonance ((1)H NMR), thermogravimetric analysis (TGA) and elemental analysis. The influences of degree of substitution (DS) of KGM, concentration of NaCl and pH value on turbidity removal rate of the cationic flocculant were investigated. The results demonstrated that the flocculant exhibited excellent flocculating ability in the presence of salt and a wide range of pH (1

Assuntos
Mananas/química , Mananas/síntese química , Cério/química , Técnicas de Química Sintética , Floculação , Concentração de Íons de Hidrogênio , Metacrilatos/química , Ácidos Polimetacrílicos/química , Compostos de Amônio Quaternário/química , Cloreto de Sódio/química
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 14(12): 982-7, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23234791

RESUMO

OBJECTIVE: To study the role and possible mechanisms of gap junctional intercellular communication (GJIC) involved in mesangial cell (MC) proliferation which could be inhibited by bufalin. METHODS: Rat mesangial cells were cultured in vitro. The effect of bufalin on platelet-derived growth factor-BB (PDGF-BB)-induced MC proliferation was evaluated by MTT assay. The function of GJIC was detected by Lucifer Yellow scrape loading and dye transfer (SLDT). mRNA levels of Cx43, Cx45 and Cx40 were measured by RT-PCR. Intracellular calcium concentrations ([Ca(2+)]i) were examined in laser scanning confocal microscopy after loading by Fura-3/AM. RESULTS: MTT indicated that bufalin could inhibited PDGF-BB-induced MC proliferation (P<0.01). Compared with the hormal control group, PDGF-BB inhibited GJIC function, increased the expression of Cx45 and Cx40 (P<0.01) without altering the Cx43 (P>0.05) in gene level and also increased [Ca(2+)]i. However, bufalin treatment enhanced GJIC function, decreased Cx45 mRNA and Cx40 mRNA expression (P<0.01), and reduced [Ca(2+)]i (P<0.01). CONCLUSIONS: Bufalin inhibits PDGF-BB-induced MC proliferation, and its possible mechanisms may be related to regulation of Cx45 and Cx40 expression in the gene level, reduction of [Ca(2+)]i and enhancement of GJIC function.


Assuntos
Bufanolídeos/farmacologia , Comunicação Celular/efeitos dos fármacos , Junções Comunicantes/efeitos dos fármacos , Células Mesangiais/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-sis/farmacologia , Animais , Becaplermina , Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Mesangiais/fisiologia , Células Mesangiais/ultraestrutura , Ratos
10.
Huan Jing Ke Xue ; 33(4): 1247-51, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22720573

RESUMO

Hematite was used as the catalyst to degrade the rhodamine B and 2,4-dichlorophenol under visible light irradiation. The effect of pH, catalyst dosage and dissolved iron on the degradation efficiency were studied. UV-Vis spectrophotometer, infrared spectrometer, fluorescence spectrophotometry and the chemical oxygen demand (COD) were employed to evaluate the mechanism during the degradation process. The result indicated that RhB could be degraded effectively by the Cata/RhB/H2O2/vis system. The optimum conditions were 0.6 g x L(-1) catalyst; pH 3.0 and 1.5 x 10(-3) mol x L(-1) H2O2. RhB was decomposed after 180 min and 56% of 2,4-DCP was degraded after 24 h by this syetem. Dissolved Fe ion was a relatively weak factor for the catalyst system. The catalyst had excellent stability with little loss of activity after 6 recycling experiments. The degradation process was dominated by the hydroxyl radical (*OH) generated in the heterogeneous Fenton-like system.


Assuntos
Compostos Férricos/química , Peróxido de Hidrogênio/química , Ferro/química , Compostos Orgânicos/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Catálise , Clorofenóis/isolamento & purificação , Luz , Processos Fotoquímicos , Rodaminas/isolamento & purificação
11.
Langmuir ; 27(7): 3982-90, 2011 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-21375328

RESUMO

A new oxadiazole-containing cyclotriphosphazene, namely, hexakis-(4-(5-phenyl-1,3,4-oxazodiazol-2-yl)-phenoxy)-cyclotriphosphazene (HPCP) was synthesized. Single-crystal nano- and microbelts of HPCP were self-assembly via two simple solution methods. The shapes of the as-prepared nano- and microstructures can be readily controlled by varying the solvent and aging time in the self-assembly process. A growth mechanism was proposed for the formation of the 1D morphological structures. Crystal structure analysis demonstrated that the overlap between the aryl units attached to the cyclotriphosphazene backbone forms effective intermolecular π-π linking for crystal growth. Electronic and optical properties of the as-prepared nano- and microstructures are investigated.

12.
World J Gastroenterol ; 16(14): 1735-41, 2010 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-20380005

RESUMO

AIM: To observe the regional distributions and morphological features of nesfatin-1/nucleobindin-2 (NUCB2) immunoreactive (IR) cells in the rodent digestive system. METHODS: Paraffin-embedded sections of seven organs (pancreas, stomach, duodenum, esophagus, liver, small intestine and colon) dissected from sprague-dawley (SD) rats and imprinting-control-region (ICR) mice were prepared. The regional distributions of nesfatin-1/NUCB2 IR cells were observed by immunohistochemical staining. The morphological features of the nesfatin-1/NUCB2 IR cells were evaluated by hematoxylin and eosin (HE) staining. Fresh tissues of the seven organs were prepared for Western blotting to analyze the relative protein levels of NUCB2 in each organ. RESULTS: Immunohistochemical staining showed that the nesfatin-1/NUCB2 IR cells were localized in the central part of the pancreatic islets, the lower third and middle portion of the gastric mucosal gland, and the submucous layer of the duodenum in SD rats and ICR mice. HE staining revealed that the morphological features of nesfatin-1/NUCB2 IR cells were mainly islet cells in the pancreas, endocrine cells in the stomach, and Brunner's glands in the duodenum. Western blotting revealed that NUCB2 protein expression was higher in the pancreas, stomach and duodenum than in the esophagus, liver, small intestine and colon (P = 0.000). CONCLUSION: Nesfatin-1/NUCB2 IR cells are expressed in the pancreas, stomach and duodenum in rodents. These cells may play an important role in the physiological regulation of carbohydrate metabolism, gastrointestinal function and nutrient absorption.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação a DNA/metabolismo , Sistema Digestório/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 10(2): 188-90, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18433544

RESUMO

OBJECTIVE: To explore the role of exogenous connective tissue growth factor (CTGF) in the collagen III synthesis of human renal tubular epithelial cell line HK2 in vitro. METHODS: Cultured HK2 cells were randomly assigned to three groups: placebo-control, low-dose CTGF-treated (2.5 ng/mL) and high-dose CTGF-treated groups (20 ng/mL). Cell morphological changes were observed under an inverted microscope. Collagen III alpha mRNA expression was detected using RT-PCR. Immunohistochemistry staining was used to assess the levels of intracellular collagen III alpha protein. RESULTS: After 48 hrs of low- or high- dose CTGF treatment, the appearances of HK2 cells were changed from oval to fusiform. High-dose CTGF treatment increased collagen III alpha mRNA expression (0.4461+/-0.0274 vs 0.2999+/-0.0115; P<0.05) as well as the protein expression of collagen III alpha (0.4075+/-0.0071 vs 0.3503+/-0.0136; P<0.05) compared with the placebo-control group. CONCLUSIONS: CTGF can induce morphological changes of human renal tubular epithelial cells in vitro. High concentration of CTGF may increase the synthesis of collagen III alpha.


Assuntos
Colágeno Tipo III/biossíntese , Proteínas Imediatamente Precoces/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Túbulos Renais/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo III/genética , Fator de Crescimento do Tecido Conjuntivo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Imuno-Histoquímica , Túbulos Renais/metabolismo , RNA Mensageiro/análise
14.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): o2047, 2008 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21201239

RESUMO

The complete molecule of the title compound, C(5)H(6)O(4)S(3), is generated by crystallographic twofold symmetry with the C=S group lying on the rotation axis. The molecules are linked through weak hydrogen-bond contacts by glide-plane operations to form R(2) (2)(20) rings and ladder-like C(4) chains along the c axis.

16.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 23(2): 127-9, 2007 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-17286905

RESUMO

AIM: To investigate the role of insulin-like growth factor I(IGF-I) in transdifferentiation and collagen synthesis of human renal tubular epithelial cell line HK2 in vitro. METHODS: Cultured HK2 cells were divided into two groups: (1) control group; (2) IGF-I-treated group(25, 50, 100, 200 microg/L, respectively). The cell morphological changes were traced with inverted microscope, and the expression of alpha-smooth muscle actin (alpha-SMA), collagen I alpha and collagen III alpha mRNA was detected by RT-PCR. Concentration of collagen I secreted into the culture supernatant was determined by ELISA. RESULTS: In HK2 cells, IGF-I stimulated the morphological oval-to-fusiform transdifferentiation of the cells, and upregulated alpha-SMA, collagen I alpha and collagen III alpha mRNA expression(P<0.05). Secreted collagen I level was also up-regulate by IGF-I in the concentration of 100 and 200 microg/L, respectively. CONCLUSION: IGF-I can promote the transdifferentiation of human renal tubular epithelial cells and stimulate the synthesis of collagen.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Colágeno/biossíntese , Colágeno/genética , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Túbulos Renais/citologia , Actinas/genética , Linhagem Celular , Transdiferenciação Celular , Colágeno Tipo I/genética , Colágeno Tipo III/genética , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/citologia , Humanos , Túbulos Renais/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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