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1.
Macromol Rapid Commun ; 43(11): e2200127, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35334130

RESUMO

Biological polyampholytes are ubiquitous in living organisms with primary functions including serving as transporters for moving chemical molecular species across the cell membranes. Synthetic amphoteric macromolecules that can change their phase states depending on the environment to simulate some properties of natural polyampholytes are of great interest. Here, the implementation of synthetic pseudo polymeric ampholytes is explored with ion-recognition-triggered conformational change. The phase transition behaviors of the ion-recognition-creative polyampholytes that contain deprotonated carboxylic acid groups as negative charges and 18-crown-6 units for forming positively charged host-guest complexes are systematically investigated. The ion-recognition-triggered phase transition behaviors of pseudo polyampholytes significantly depend on cation species and concentrations. Only those specific ions such as K+ , Ba2+ , Sr2+ and Pb2+ ions that can form 1:1 host-guest complexes with 18-crown-6 units in polymers enable control over conformational change like that of traditional pH-dependent polyampholytes. By regulating the content of carboxylic acid groups to match the content of ion-recognized positive charges provided by the host-guest complexes, the pseudo polyampholytes are more sensitive to the recognizable cations. Such ion-recognition-triggered amphoteric characteristics make the pseudo polyampholytes act like biological proteins, nucleic acids, and enzymes as molecular transporters, genetic code storage, and biocatalysts in artificial systems.


Assuntos
Ácidos Carboxílicos , Polímeros , Íons/química , Conformação Molecular , Transição de Fase , Polímeros/química
2.
J Hazard Mater ; 421: 126801, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34388916

RESUMO

A novel chemosensor is developed for the sensitive and facile detection of trace strontium ions (Sr2+) based on the ion-imprinted hydrogels. With Sr2+ as the templates, the ion-imprinted hydrogels are synthesized by copolymerizing the ion-responsive units 5'-O-acryloyl-2',3'-O-isopropylidene guanosine (APG) and the thermo-responsive units N-isopropylacrylamide (NIPAM). In the presence of Sr2+, APG units can self-assemble to form planar G-quartets via the complexation with Sr2+, which are introduced into the gel network during polymerization. Then Sr2+ templates can be removed by multiple repeated washing. When re-exposed to Sr2+, the relaxed G-quartets can recognize Sr2+, leading to the weakening of electrostatic repulsion between the four oxygen atoms in the G-quartets and inducing the shrinkage of the hydrogels. In this work, the Sr2+-imprinted chemosensors are designed as the grating systems for detecting trace Sr2+. Based on the array of hydrogel strings synthesized on a nano-scale, the smart grating systems thus constructed can convert and amplify the Sr2+ concentration signals to the easily-measurable optical signals. With the Sr2+-imprinted hydrogel gratings, trace Sr2+ (10-11 M) in an aqueous solution can be detected sensitively. Moreover, the proposed Sr2+-imprinted chemosensors can be integrated with other smart systems for developing various detectors with high performance.


Assuntos
Hidrogéis , Estrôncio , Guanosina , Íons , Polimerização
3.
ACS Appl Mater Interfaces ; 13(24): 28802-28817, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34109788

RESUMO

In this study, a novel class of multifunctional responsive nanoparticles is designed and fabricated as drug nanocarriers for synergetic chemo-photothermal therapy of tumors. The proposed nanoparticles are composed of a thermo-/pH-responsive poly(N-isopropylacrylamide-co-acrylic acid) (PNA) nanogel core, a polydopamine (PDA) layer for photothermal conversion, and an outer folic acid (FA) layer as a targeting agent for the folate receptors on tumor cells. The fabricated nanoparticles show good biocompatibility and outstanding photothermal conversion efficiency. The proposed nanoparticles loaded with doxorubicin (DOX) drug molecules are stable under physiological conditions with low leakage of drugs, while rapidly release drugs in environments with low pH conditions and at high temperature. The experimental results show that the drug release process is mainly governed by Fickian diffusion. In vitro cell experimental results demonstrate that the PNA-DOX@PDA-FA nanoparticles can be phagocytized by 4T1 tumor cells and release drugs in tumor cell acidic environments, and confirm that the combined chemo and photothermal therapeutic efficacy of PNA-DOX@PDA-FA nanoparticles is higher than the photothermal therapeutic efficacy or the chemotherapeutic efficacy alone. The proposed multifunctional responsive nanoparticles in this study provide a novel class of drug nanocarriers as a promising tool for synergetic chemo-photothermal therapy of tumors.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Nanopartículas Multifuncionais/química , Acrilamidas/química , Acrilamidas/metabolismo , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/metabolismo , Portadores de Fármacos/efeitos da radiação , Liberação Controlada de Fármacos , Endocitose/fisiologia , Ácido Fólico/análogos & derivados , Ácido Fólico/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Indóis/química , Indóis/metabolismo , Indóis/efeitos da radiação , Raios Infravermelhos , Camundongos , Nanopartículas Multifuncionais/metabolismo , Terapia Fototérmica , Polímeros/química , Polímeros/metabolismo , Polímeros/efeitos da radiação , Temperatura
4.
Aging (Albany NY) ; 13(10): 14001-14014, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34030135

RESUMO

Vascular dementia (VaD) is the second most common type of dementia worldwide. Although there are five FDA-approved drugs for the treatment of Alzheimer's disease (AD), none of them have been applied to treat VaD. Adalimumab is a TNF-α inhibitor that is used for the treatment of autoimmune diseases such as rheumatoid arthritis. In a recent retrospective case-control study, the application of adalimumab for rheumatoid or psoriasis was shown to decrease the risk of AD. However, whether adalimumab can be used for the treatment of VaD is not clear. In this study, we used 2VO surgery to generate a VaD rat model and treated the rats with adalimumab or vehicle. We demonstrated that VaD rats treated with adalimumab exhibited significant improvements in memory. In addition, adalimumab treatment significantly alleviated neuronal loss in the hippocampi of VaD rats. Moreover, adalimumab significantly reduced microglial activation and reversed M1/M2 polarization in VaD rats. Furthermore, adalimumab treatment suppressed the activity of NF-κB, an important neuroinflammatory transcription factor. Finally, adalimumab displayed a protective role against oxidative stress in VaD rats. Our results indicate that adalimumab may be applied for the treatment of human patients with VaD.


Assuntos
Adalimumab/uso terapêutico , Encéfalo/patologia , Circulação Cerebrovascular/fisiologia , Inflamação/patologia , Transtornos da Memória/tratamento farmacológico , Adalimumab/farmacologia , Animais , Biomarcadores/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Doença Crônica , Transtornos da Memória/fisiopatologia , Microglia/efeitos dos fármacos , Microglia/patologia , NF-kappa B/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
5.
J Hazard Mater ; 404(Pt A): 124157, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33039826

RESUMO

A simple and portable thermometer-type device based on forward osmosis-driven liquid column rising is developed for visual detection of trace Pb2+. The device consists of a top indicator tube, a chamber loaded with Pb2+-responsive poly(N-isopropylacrylamide-co-benzo-18-crown-6-acrylamide) (PNB) smart nanogels and a bottom semipermeable membrane. Upon the recognition of Pb2+, PNB smart nanogels undergo a Pb2+-induced hydrophobic to hydrophilic transition, which simultaneously causes the increase of osmotic pressure inside the device. Driven by this osmotic pressure difference, more Pb2+ solution flows into the device, causing the rise of the liquid column in the indicator tube, which can be directly observed by naked eyes. The relationship between the change of liquid column height and the Pb2+ concentration is investigated for the quantitative detection of Pb2+. With the proposed forward osmosis-driven device, trace Pb2+ as low as 10-10 M in aqueous solutions can be detected. This method provides a novel and simple strategy for the visual detection of trace Pb2+.

6.
ACS Appl Mater Interfaces ; 9(16): 14409-14421, 2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28398718

RESUMO

Facile fabrication of novel functional membranes with excellent dual thermo- and pH-responsive characteristics has been achieved by simply designing dual-layer composite membranes. pH-Responsive poly(styrene)-block-poly(4-vinylpyridine) (PS-b-P4VP) block copolymers and polystyrene blended with thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) nanogels are respectively used to construct the top layer and bottom layer of composite membranes. The stretching/coiling conformation changes of the P4VP chains around the pKa (∼3.5-4.5) provide the composite membranes with extraordinary pH-responsive characteristics, and the volume phase transitions of PNIPAM nanogels at the pore/matrix interfaces in the bottom layer around the volume phase transition temperature (VPTT, ∼33 °C) provide the composite membranes with great thermoresponsive characteristics. The microstructures, permeability performances, and dual stimuli-responsive characteristics can be well tuned by adjusting the content of PNIPAM nanogels and the thickness of the PS-b-P4VP top layer. The water fluxes of the composite membranes can be changed in order of magnitude by changing the environment temperature and pH, and the dual thermo- and pH-responsive permeation performances of the composite membranes are satisfactorily reversible and reproducible. The membrane fabrication strategy in this work provides valuable guidance for further development of dual stimuli-responsive membranes or even multi stimuli-responsive membranes.

7.
Biomed Pharmacother ; 83: 593-601, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27459115

RESUMO

Increasing study reports that Wnt/ß-catenin signaling pathway plays an essential role in numerous cancers growth, progression and metastasis. Aberrant miR-940 expression has been studied in gastric and breast cancer. However, the molecular mechanism of miR-940 enhancing proliferation and metastatic ability in human pancreatic carcinoma is far from to know. Real-time PCR was used to quantify miR-940 expression. Luciferase reporter assays here were performed to verify the activity of Wnt/ß-catenin signaling pathway and targeting gene relationships, and immunofluorescence assay was applied to observe ß-catenin expressed intensity. Bioinformatics analysis together with in vivo and vitro functional analysis indicated the potential targeting genes of miR-940. Specimens from 15 pairs of patients with human pancreatic carcinoma were involoved to confirm the relationship between miR-940 expression and the GSK3ß/sFRP1 through real-time PCR and western blot assays. Bioinformatics combined with cell luciferase function researches determined the possible regulation of miR-940 on the 3'-UTR of the GSK3ß and sFRP1 genes, resulting in the Wnt/ß-catenin signaling activation. Further, miR-940 knockdown significantly recovered GSK3ß and sFRP1 expression and relieved Wnt/ß-catenin-mediated cell invasion, migration, metastasis and proliferation. The ectopic up-regulation of miR-940 significantly suppressed GSK3ß/sFRP1 expression and promoted pancreatic carcinoma proliferation and invasion. Our study suggested mechanistic relationship between miR-940 and Wnt/ß-catenin in the development and progression of pancreatic carcinoma through regulation of GSK3ß and sFRP1.


Assuntos
Glicogênio Sintase Quinase 3 beta/metabolismo , MicroRNAs/metabolismo , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/genética , Proteínas/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Neoplasias Pancreáticas/patologia , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias Pancreáticas
8.
Biomed Pharmacother ; 82: 595-605, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27470402

RESUMO

Cervical cancer is a cause of cancer death, making it as the one of the most common cause for death among women globally. Though many studies before have explored a lot for cervical cancer prevention and treatment, there are still a lot far from to know based on the molecular mechanisms. Janus kinase 2 (JAK2) has been reported to play an essential role in the progression of apoptosis, autophagy and proliferation for cells. We loaded gold-quercetin into poly (dl-lactide-co-glycolide) nanoparticles to cervical cancer cells due to the propertities of quercetin in ameliorating cellular processes and the easier absorbance of nanoparticles. Here, in our study, quercetin nanoparticles (NQ) were administrated to cells to investigate the underlying mechanism by which the cervical cancer was regulated. First, JAK2-inhibited carvical cancer cell lines were involved for our experiments in vitro and in vivo. Western blotting, quantitative RT-PCR (qRT-PCR), ELISA, Immunohistochemistry, and flow-cytometric analysis were used to determine the key signaling pathway regulated by JAK2 for cervical cancer progression. And the role of quercetin nanoparticles was determined during the process. Data here indicated that JAK2, indeed, expressed highly in cancer cell lines compared to the normal cervical cells. And apoptosis and autophagy were found in JAK2-inhibited cancer cells through activating Caspase-3, and suppressing Cyclin-D1 and mTOR regulated by Signal Transducer and Activator of Transcription (STAT) 3/5 and phosphatidylinositide 3-kinase/protein kinases (PI3K/AKT) signaling pathway. The cervical cancer cells proliferation was inhibited. Further, tumor size and weight were reduced by inhibition of JAK2 in vivo experiments. Notably, administration with quercetin nanoparticles displayed similar role with JAK2 suppression, which could inhibit cervical cancer cells proliferation, invasion and migration. In addition, autophogy and apoptosis were induced, promoting cervical cancer cell death. To our knowledge, it was the first time to evaluate the role of quercetin nanoparticles in improving cervical cancer from apoptosis, autophagy and proliferation, which could be a potential target for future therapeutic approach clinically.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Progressão da Doença , Janus Quinase 2/metabolismo , Nanopartículas/química , Quercetina/farmacologia , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Transdução de Sinais/efeitos dos fármacos , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Zhonghua Xue Ye Xue Za Zhi ; 34(6): 485-8, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23827102

RESUMO

OBJECTIVE: Two children with hydroa vacciniforme-like lymphoma (HVLL) were reported for a better understanding of this disease. METHODS: The clinical manifestation, pathological characteristics, therapeutic outcomes of two children with HVLL were analyzed and presented by compared with what described in literatures. RESULTS: Two children were girls, who treated firstly in the hospital in May 2012, July 2012 and their duration were 1 years, more than 10 years respectively. Their clinical manifestations were both limbs and craniofacial polymorphous rashes. Pathological findings revealed that the dermis and subcutaneous tissue were profiled by atypical lymphocytic infiltration. Immunohistochemistry showed that the infiltration of cells from T/NK cell, and Epstein-Barr virus encoded small RNA (EBER)(+). Case 1 was treated with chemotherapy, but her condition continued to deteriorate. Case 2 just received symptomatic treatment, her skin lesions gradually reduced and rash disappeared completely 2 months later. CONCLUSION: HVLL is found with special clinical manifestation, its diagnosis mainly depend on skin biopsy and immunohistochemistry, there is no specific treatment method now, and its prognosis still needs further research.


Assuntos
Linfoma Cutâneo de Células T , Neoplasias Cutâneas , Criança , Pré-Escolar , Feminino , Humanos , Hidroa Vaciniforme
10.
Zhonghua Zhong Liu Za Zhi ; 30(8): 566-72, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19102931

RESUMO

OBJECTIVE: To investigate the inhibitory effect of nanoparticle-mediated antisense oligodeoxynucleotide (ASODN) of human telomerase reverse transcriptase (hTERT) on telomerase in the esophageal cancer EC9706 cells. METHODS: Line-polyethylenimine (L-PEI) was used to condense ASODN into nanoparticle and to couple NGR peptides into targeting nanoparticle, and the prepared L-PEI/ASODN complexes were transfected into the EC9706 cells. Cellular uptake of L-PEI/ASODN complexes was detected by laser confocal scanning microscopy. MTT assay was used to detect the inhibitory rate of EC9706 cell growth. The level of hTERT mRNA and its protein expression were measured by RT-PCR and immunohistochemistry, respectively. Annexin V FITC/PI double labeling was used to detect cell apoptosis. The distribution of drug in nude mice was observed by laser confocal scanning microscopy, and the growth and morphology of the tumor was examined. RESULTS: The L-PEI-mediated ASODN uptake was enhanced. After transfection, the inhibitory rate of EC9706 cells was time-dependant and there was a significant difference between control cell group and L-PEI/ASODN group (P < 0.05). At 48 h after transfection, the level of hTERT mRNA was decreased significantly compared with that of control cell group (P < 0.05), and the expression of hTERT protein was negative. There was apparent apoptosis in EC9706 cells after transfection with L-PEI/ASODN complexes. For the two NGR/L-PEI/ASODN groups, fluorescence was observed in the liver, kidney, lung and tumor tissues of nude mice, and their uptake intensity was time-dependent. The mean volume of tumors in the two NGR/L-PEI/ASODN groups was significantly smaller than those in blank control group and SODN group (P < 0.05). Apoptotic bodies were detected in the tumors of L-PEI/ASODN group. CONCLUSION: The NGR/L-PEI/ASODN nanoparticles can effectively reach into the human esophageal cancer xenograft and inhibit the tumor growth in nude mice, and this may provide a theoretical and experimental basis for gene therapy for human esophageal squamous cell carcinoma.


Assuntos
Apoptose , Neoplasias Esofágicas , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Telomerase/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Feminino , Vetores Genéticos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas , Transplante de Neoplasias , Oligodesoxirribonucleotídeos Antissenso/genética , Oligopeptídeos/química , Oligopeptídeos/farmacocinética , Polietilenoimina/química , Polietilenoimina/farmacocinética , RNA Mensageiro/metabolismo , Telomerase/genética , Distribuição Tecidual , Transfecção , Carga Tumoral
11.
Arch Pathol Lab Med ; 132(8): 1307-12, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18684031

RESUMO

CONTEXT: Phosphatase of regenerating liver (PRL) 3 messenger RNA (mRNA) was reported to express in human colorectal, gastric, ovarian, breast, and hepatic cancers. OBJECTIVE: To examine the expression of PRL-1 and PRL-3 mRNAs in human esophageal squamous cell carcinoma (ESCC). DESIGN: Expression of PRL-1 and PRL-3 mRNA was examined with reverse transcriptase-polymerase chain reaction in fresh tissue collected from 40 cases of ESCC with matched lymph node metastasis in 21 cases. The association of expression of PRL-1 and PRL-3 mRNAs with clinicopathologic parameters was analyzed. RESULTS: The frequencies of PRL-1 and PRL-3 mRNA expression were significantly higher in ESCC than in normal esophageal tissue (P = .001; P = .01) and also significantly higher in ESCC with lymph node metastasis than in those without lymph node metastasis (P = .01; P = .03). The levels of PRL-1 and PRL-3 mRNA expression were significantly higher in ESCC with lymph node metastasis than in those without lymph node metastasis (P = .04; P = .04). The frequencies and levels of PRL-1 and PRL-3 mRNA expression were correlated with the later stages but not with tumor differentiation, tumor location in the esophagus, patient's sex, and age. CONCLUSIONS: PRL-1 and PRL-3 mRNAs may be involved in and used to predict the metastasis of ESCC. The possibility of using PRL-1 and PRL-3 as the therapeutical target is also discussed.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Proteínas de Ciclo Celular/genética , Neoplasias Esofágicas/enzimologia , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Proteínas Tirosina Fosfatases/genética , RNA Mensageiro/metabolismo , Adulto , Idoso , Carcinoma de Células Escamosas/secundário , Neoplasias Esofágicas/patologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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