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1.
Environ Sci Technol ; 58(3): 1752-1762, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38190653

RESUMO

The widespread presence of formaldehyde (HCHO) pollutant has aroused significant environmental and health concerns. The catalytic oxidation of HCHO into CO2 and H2O at ambient temperature is regarded as one of the most efficacious and environmentally friendly approaches; to achieve this, however, accelerating the intermediate formate species formation and decomposition remains an ongoing obstacle. Herein, a unique tandem catalytic system with outstanding performance in low-temperature HCHO oxidation is proposed on well-structured Pd/Mn3O4-MnO catalysts possessing bifunctional catalytic centers. Notably, the optimized tandem catalyst achieves complete oxidation of 100 ppm of HCHO at just 18 °C, much better than the Pd/Mn3O4 (30%) and Pd/MnO (27%) counterparts as well as other physical tandem catalysts. The operando analyses and physical tandem investigations reveal that HCHO is primarily activated to gaseous HCOOH on the surface of Pd/Mn3O4 and subsequently converted to H2CO3 on the Pd/MnO component for deep decomposition. Theoretical studies disclose that Pd/Mn3O4 exhibits a favorable reaction energy barrier for the HCHO → HCOOH step compared to Pd/MnO; while conversely, the HCOOH → H2CO3 step is more facilely accomplished over Pd/MnO. Furthermore, the nanoscale intimacy between two components enhances the mobility of lattice oxygen, thereby facilitating interfacial reconstruction and promoting interaction between active sites of Pd/Mn3O4 and Pd/MnO in local vicinity, which further benefits sustained HCHO tandem catalytic oxidation. The tandem catalysis demonstrated in this work provides a generalizable platform for the future design of well-defined functional catalysts for oxidation reactions.


Assuntos
Formaldeído , Paládio , Temperatura , Domínio Catalítico , Oxirredução , Catálise , Paládio/química
2.
Oncogenesis ; 12(1): 34, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355711

RESUMO

Cancer relapse and metastasis are major obstacles for effective treatment. One important mechanism to eliminate cancer cells is to induce apoptosis. Activation of executioner caspases is the key step in apoptosis and was considered "a point of no return". However, in recent years, accumulating evidence has demonstrated that cells can survive executioner caspase activation in response to apoptotic stimuli through a process named anastasis. Here we show that breast cancer cells that have survived through anastasis (anastatic cells) after exposure to chemotherapeutic drugs acquire enhanced proliferation and migration. Mechanistically, cadherin 12 (CDH12) is persistently upregulated in anastatic cells and promotes breast cancer malignancy via activation of ERK and CREB. Moreover, we demonstrate that executioner caspase activation induced by chemotherapeutic drugs results in loss of DNA methylation and repressive histone modifications in the CDH12 promoter region, leading to increased CDH12 expression. Our work unveils the mechanism underlying anastasis-induced enhancement in breast cancer malignancy, offering new therapeutic targets for preventing post-chemotherapy cancer relapse and metastasis.

3.
Cell Death Dis ; 14(6): 388, 2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37391410

RESUMO

Chemotherapy is a common strategy to treat cancer. However, acquired resistance and metastasis are the major obstacles to successful treatment. Anastasis is a process by which cells survive executioner caspase activation when facing apoptotic stress. Here we demonstrate that colorectal cancer cells can undergo anastasis after transient exposure to chemotherapeutic drugs. Using a lineage tracing system to label and isolate cells that have experienced executioner caspase activation in response to drug treatment, we show that anastasis grants colorectal cancer cells enhanced migration, metastasis, and chemoresistance. Mechanistically, treatment with chemotherapeutic drugs induces upregulated expression of cIAP2 and activation of NFκB, which are required for cells to survive executioner caspase activation. The elevated cIAP2/NFκB signaling persists in anastatic cancer cells to promote migration and chemoresistance. Our study unveils that cIAP2/NFκB-dependent anastasis promotes acquired resistance and metastasis after chemotherapy.


Assuntos
Reversão da Morte Celular , Neoplasias Colorretais , Humanos , Resistencia a Medicamentos Antineoplásicos , NF-kappa B , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Caspases
4.
Huan Jing Ke Xue ; 43(4): 1966-1975, 2022 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-35393820

RESUMO

In order to reveal the pollution and risk level of phthalic acid esters (PAEs) in Qiandao Lake, six types of PAEs in 17 sampling points (in Qiandao Lake and its inflowing rivers) in dry and wet seasons were detected. The results showed that six types of PAEs were detected in both dry and wet seasons, with the concentrations of 0.98-5.33 µg·L-1 (average concentration 2.63 µg·L-1) in the dry season and 3.22-17.88 µg·L-1 (average concentration 7.99 µg·L-1) in the wet season. In terms of the detection rate and concentration of each monomer PAEs, DiBP, DBP, and DEHP were the main PAEs components in the water body. The measured value of DBP at 10 sampling points and its average mass concentration in the wet season were higher than the national standard (3 µg·L-1). Principal component analysis indicated that the main sources of PAEs were personal care products, plastics, and domestic waste. The pollution level of PAEs in Qiandao Lake was at a high level at home and abroad. The health risk assessment results in Qiandao Lake showed that the non-carcinogenic risk index of PAEs in the study area was less than 1, which would not produce non-carcinogenic risks to the human body. The carcinogenic risk index of children exceeded 10-6 at some points, indicating that it may pose carcinogenic risks to children, to which more attention should be paid.


Assuntos
Ácidos Ftálicos , Poluentes Químicos da Água , Criança , China , Dibutilftalato , Ésteres/análise , Humanos , Lagos , Ácidos Ftálicos/análise , Medição de Risco , Água/análise , Poluentes Químicos da Água/análise
5.
Med Chem ; 18(5): 589-601, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34463229

RESUMO

BACKGROUND: Breast cancer is the leading cause of cancer death in women. The current methods of chemotherapy for breast cancer generally have strong adverse reactions and drug resistance. Therefore, the discovery of novel anti-breast cancer lead compounds is urgently needed. OBJECTIVE: This study aimed to design and synthesize a series of 2-alkyl substituted fluorinated genistein analogues and evaluate their anti-breast cancer activity. METHODS: Target compounds were obtained in a multistep reaction synthesis. The anti-tumor activity of compounds I-1~I-35 was evaluated with MCF-7, MDA-MB-231, MDA-MB-435, and MCF-10A cell lines in vitro, with tamoxifen as the positive control. Molecular docking was used to study the interaction between the synthesized compounds and PI3K-gamma. RESULTS: A series of 2-alkyl substituted fluorinated genistein analogues was designed, synthesized, and screened for their bioactivity. Most of the compounds displayed better selectivity toward breast cancer cell lines as compared to tamoxifen. Among these analogues, I-2, I-3, I-4, I-9, I-15, and I-17 have the strongest selective inhibition of breast cancer cells. Compounds I-10, I-13, I-15, I-17, and I- 33 were found to have significant inhibitory effects on breast cancer cells. Molecular docking studies have shown that these compounds may act as PI3Kγ inhibitors and may further exhibit anti-breast cancer effects. CONCLUSION: Most of the newly synthesized compounds could highly, selectively inhibit breast cancer cell lines. The experimental results indicate that the synthesized analogs may also have obvious selective inhibitory effects on other malignant proliferation cancer cells.


Assuntos
Antineoplásicos , Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Relação Dose-Resposta a Droga , Feminino , Genisteína/farmacologia , Genisteína/uso terapêutico , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
6.
Stem Cell Reports ; 17(1): 159-172, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34971563

RESUMO

Transplantation in Parkinson's disease using human embryonic stem cell (hESC)-derived dopaminergic (DA) neurons is a promising future treatment option. However, many of the mechanisms that govern their differentiation, maturation, and integration into the host circuitry remain elusive. Here, we engrafted hESCs differentiated toward a ventral midbrain DA phenotype into the midbrain of a preclinical rodent model of Parkinson's disease. We then injected a novel DA-neurotropic retrograde MNM008 adeno-associated virus vector capsid, into specific DA target regions to generate starter cells based on their axonal projections. Using monosynaptic rabies-based tracing, we demonstrated for the first time that grafted hESC-derived DA neurons receive distinctly different afferent inputs depending on their projections. The similarities to the host DA system suggest a previously unknown directed circuit integration. By evaluating the differential host-to-graft connectivity based on projection patterns, this novel approach offers a tool to answer outstanding questions regarding the integration of grafted hESC-derived DA neurons.


Assuntos
Diferenciação Celular , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Sinapses/metabolismo , Biomarcadores , Rastreamento de Células , Expressão Gênica , Genes Reporter , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Mesencéfalo/metabolismo , Fenótipo , Proteínas Serina-Treonina Quinases/genética , Transplante de Células-Tronco
7.
Chem Commun (Camb) ; 57(49): 6070-6073, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34036988

RESUMO

The electronic structure of catalysts influences the electrocatalytic behavior. Herein, the electronic structure of NiO nanocrystals is modified by doping with a small amount of Li+. The Li+ doped NiO nanocrystals show much better OER activity than pristine NiO and LiNiO2, which is a result of tuned Fermi levels, stronger hybridization between Ni 3d and O 2p, and narrowed energy band gap. This work provides a facile strategy to regulate NiO electronic energy bands to promote OER performance.

8.
Dalton Trans ; 49(31): 10918-10927, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32720957

RESUMO

Because of their low cost and Earth-abundant characteristics, materials based on 3d transition metals have attracted great research interest and are considered as promising electrocatalysts for the oxygen evolution reaction (OER), besides the commercial noble metal-based materials, in recent years. In order to improve electrocatalytic activity, it is necessary to design the structures and compositions of electrocatalysts. In this study, a series of multi-shelled CoxNi1-x oxide/phosphide hollow spheres with tunable element ratios were prepared. The electrocatalytic activity of the multi-shelled CoxNi1-x oxide/phosphide is strongly dependent on the molar ratio of Co and Ni. Based on the combined advantages of complex structures and compositions, the multi-shelled Co0.5Ni0.5 oxide/phosphide displays outstanding electrocatalytic performance in terms of high activity and stable durability for the OER, surpassing those of RuO2 and multi-shelled CoxNi1-x oxide/phosphide with other element ratios of Co and Ni. This result suggests a great possibility of rationally designing the composition for highly efficient electrocatalysts.

9.
Medicine (Baltimore) ; 99(14): e19673, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32243402

RESUMO

INTRODUCTION: Interstitial cystitis (IC), as a common disease in urology, is prolonged and repeated. IC has caused great harm to the patient's physical and psychological. Traditional Chinese medicine (TCM) is characterized by overall concepts and dialectical treatment. It provides clinicians with safer and more reliable alternatives in terms of clinical prescriptions and prepared medicines, and also improves the quality of life of patients with IC. Therefore, in this study, we will use the research method of randomized controlled trials to explore the effects of TCM combined with western medicine on renal function and urine metabolism on middle-aged women with IC. METHODS/DESIGN: Use randomized controlled trials. According to the proposed diagnostic, inclusion, and exclusion criteria. Sixty patients with interstitial bladder inflammation that met the criteria were randomized into a treatment group and a control group of 30 cases each. The intervention group was treated with integrated traditional Chinese and western medicine. The control group was given conventional Western medicine treatment. The course of treatment is 8 weeks. Interstitial bladder inflammation symptoms score (ICS worker), problem score (worker CPI), pelvic pain and urinary urgency symptoms, and urodynamics were used as the evaluation criteria. DISCUSSION: This trial may provide evidence regarding the clinical effectiveness, safety, and cost-effectiveness of TCM for patients with IC. TRIAL REGISTRATION: ClinicalTrials.gov, ChiCTR2000029971, Registered on 17 February 2020.


Assuntos
Cistite Intersticial/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa/métodos , Agentes Urológicos/farmacologia , Cistite Intersticial/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Método Simples-Cego , Resultado do Tratamento , Urodinâmica/efeitos dos fármacos
10.
J BUON ; 24(3): 907-912, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424641

RESUMO

PURPOSE: The main objective of the current study was to examine the anticancer effects of Curzerenone - a naturally occurring sesquiterpene against gemcitabine-resistant lung carcinoma cells. The effects of Curzerenone on mitochondrial-mediated apoptosis, ROS, and ERK/MAPK and NF-kB signalling pathways were also investigated in the present study. METHODS: Cell proliferation was evaluated by MTT assay. Apoptosis was detected by acridine orange (AO)/ethidium bromide (EB) and DAPI staining as well as flow cytometry using annexin V apoptosis assay. The effects on reactive oxygen species (ROS) as well as mitochondrial membrane potential (MMP) were examined by flow cytometry. Protein expression was examined by western blotting. RESULTS: It was found that Curzerenone induced potent antiproliferative effects against the gemcitabine-resistant lung cancer cells and exhibited an IC50 of 24 µM. The anticancer effects of curzerenone were due to the induction of apoptosis which was also associated with alteration of apoptosis-related proteins (Bax,Bcl-2). Curzerenone also caused ROS-mediated alterations in the MMP. Curzerenone induced cell death in gemcitabine-resistant lung cancer cells by activating p38 MAPK/ERK signalling pathway while NF-kB pathway was inhibited in a dose-dependent manner. CONCLUSIONS: In conclusion, the current results strongly indicate that Curzerenone may prove a potential anticancer drug candidate against drug-resistant lung cancer.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , NF-kappa B/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Terpenos/uso terapêutico , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/patologia , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio , Transdução de Sinais , Terpenos/farmacologia
11.
Chem Commun (Camb) ; 55(62): 9212-9215, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31309946

RESUMO

Co3FePx/C nanocomposites were derived from one-step phosphorization of anthraquinone-2-sulfonate (AQS2) intercalated Co3Fe layered double hydroxides (Co3Fe LDHs). The carbonized AQS2 confines Co3FePx nanoparticles in the amorphous carbon matrix during thermal treatment. Ultra-small and uniformly distributed Co3FePx/C nanoparticles in carbon exhibit excellent durability and outstanding OER catalytic activity.

12.
Methods Mol Biol ; 1634: 235-246, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28819856

RESUMO

Circulating tumor cell (CTC) as an important component in "liquid biopsy" holds crucial clinical relevance in cancer prognosis, treatment efficiency evaluation, prediction and potentially early detection. Here, we present a Fiber-optic Array Scanning Technology (FAST) that enables antigen-agnostic, size-agnostic detection of CTC. By immunofluorescence staining detection of a combination of a panel of markers, FAST technology can be applied to detect rare CTC in non-small cell lung cancer (NSCLC) setting with high sensitivity and specificity. In combination with Automated Digital Microscopy (ADM) platform, companion markers on CTC such as Vimentin and Programmed death-ligand 1 (PD-L1) can also be analyzed to further characterize these CTCs. FAST data output is also compatible with downstream single cell picking platforms. Single cell can be isolated post ADM confirmation and used for "actionable" genetic mutations analysis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Tecnologia de Fibra Óptica/métodos , Imunofluorescência/métodos , Neoplasias Pulmonares/diagnóstico , Células Neoplásicas Circulantes/patologia , Análise de Célula Única/métodos , Anticorpos Monoclonais/química , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Detecção Precoce de Câncer , Tecnologia de Fibra Óptica/instrumentação , Imunofluorescência/instrumentação , Corantes Fluorescentes/química , Humanos , Queratinas/genética , Queratinas/imunologia , Queratinas/metabolismo , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/imunologia , Antígenos Comuns de Leucócito/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Mucina-1/genética , Mucina-1/imunologia , Mucina-1/metabolismo , Células Neoplásicas Circulantes/imunologia , Células Neoplásicas Circulantes/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/imunologia , Receptor ErbB-2/metabolismo , Sensibilidade e Especificidade , Análise de Célula Única/instrumentação , Vimentina/genética , Vimentina/imunologia , Vimentina/metabolismo
13.
Adv Exp Med Biol ; 994: 275-284, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28560680

RESUMO

We present here an experimental approach for exploring a new class of tumor biomarkers that are overexpressed by circulating tumor cells (CTCs) and are likely targetable in immunotherapy against tumor metastasis. Using carbohydrate microarrays, anti-tumor monoclonal antibodies (mAbs) were scanned against a large panel of carbohydrate antigens to identify potential tumor glycan markers. Subsequently, flow cytometry and fiber-optic array scanning technology (FAST) were applied to determine whether the identified targets are tumor-specific cell-surface markers and are, therefore, likely suitable for targeted immunotherapy. Finally, the tumor glycan-specific antibodies identified were validated using cancer patients' blood samples for their performance in CTC-detection and immunotyping analysis. In this article, identifying breast CTC-specific glycan markers and targeting mAbs serve as examples to illustrate this tumor biomarker discovery strategy.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias/sangue , Células Neoplásicas Circulantes/metabolismo , Polissacarídeos/sangue , Anticorpos Antineoplásicos/química , Humanos , Imunoterapia/métodos , Neoplasias/terapia , Análise Serial de Proteínas/métodos
14.
Arch Med Res ; 46(8): 642-50, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26657044

RESUMO

BACKGROUND AND AIMS: Recognition of abnormal glycosylation in virtually every cancer type has raised great interest in exploration of the tumor glycome for biomarker discovery. Identifying glycan markers of circulating tumor cells (CTCs) represents a new development in tumor biomarker discovery. The aim of this study was to establish an experimental approach to enable rapid screening of CTCs for glycan marker identification and characterization. METHODS: We applied carbohydrate microarrays and a high-speed fiber-optic array scanning technology (FAST scan) to explore potential glycan markers of breast CTCs (bCTCs) and targeting antibodies. An anti-tumor monoclonal antibody, HAE3-C1 (C1), was identified as a key immunological probe in this study. RESULTS: In our carbohydrate microarray analysis, C1 was found to be highly specific for an O-glycan cryptic epitope, gp(C1). Using FAST-scan technology, we established a procedure to quantify expression levels of gp(C1) in tumor cells. In blood samples from five stage IV metastatic breast cancer patients, the gp(C1) positive CTCs were detected in all subjects; ∼40% of bCTCs were strongly gp(C1) positive. Interestingly, CTCs from a triple-negative breast cancer patient with multiple sites of metastasis were predominantly gp(C1) positive (92.5%, 37/40 CTCs). CONCLUSIONS: Together we present here a practical approach to examine rare cell expression of glycan markers. Using this approach, we identified an O-core glyco-determinant gp(C1) as a potential immunological target of bCTCs. Given its bCTC-expression profile, this target warrants an extended investigation in a larger cohort of breast cancer patients.


Assuntos
Anticorpos Monoclonais/imunologia , Biomarcadores Tumorais/sangue , Neoplasias da Mama/patologia , Células Neoplásicas Circulantes/imunologia , Polissacarídeos/imunologia , Adulto , Linhagem Celular Tumoral , Feminino , Glicosilação , Humanos , Pessoa de Meia-Idade , Projetos Piloto
15.
J Colloid Interface Sci ; 454: 216-25, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26037271

RESUMO

Highly crystalline flake-like CuCeO2-δ composites (strCCx) with large specific surface area and developed mesoporosity were prepared using an economic and effective bio-template route. Modified starch with abundant surface carboxyl groups was adopted as the chelating agent and template for metal cations immobilization via electrostatic attraction predominately based on the process of -COO(-)⋯Cu(2+) and -COO(-)⋯Ce(3+). Physicochemical properties of prepared materials were systematically explored by FT-IR, XRD, TG, N2 adsorption/desorption, FE-SEM, TEM, H2-TPR, O2-TPD, XPS, DRUV-Vis, and XAFS techniques. Propanal as a typical oxygen-contained VOC was adopted as the probe pollutant to evaluate the catalytic performance of synthesized materials. Characterization results reveal that plenty of copper ions in composite oxides are incorporated into CeO2 lattice, which produces oxygen vacancies and enhances metal reducibility. Both specific surface area and pore volume of strCCx samples decreased with the increasing of Cu loading. The flake-like CuCeO2-δ sample (Cu/(Cu+Ce)=0.15) with highest specific surface area (108.2m(2)/g) and surface oxygen concentration is indentified as the most active catalyst with propanal totally destructed at 230°C. The introduction of H2O has a negative effect on propanal removal, and the synthesized catalyst has high tolerance to moisture. In conclusion, the specific surface area and surface oxygen density are two vital factors governing the catalytic activity of composite catalysts.

16.
Water Sci Technol ; 71(5): 754-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25768223

RESUMO

A novel bioelectrochemical system (BES) was designed to recover copper and nickel from wastewater sequentially. The BES has two chambers separated by a bipolar membrane and two cathodes. Firstly, the copper ions were reduced on a graphite cathode with electricity output, and then with an additional bias-potential applied, the nickel ions were recovered sequentially on a copper sheet with electricity input. In this design, nickel and copper can be recovered and separated sequentially on two cathodes. By adjusting the molar ratio of copper and nickel ions to 2.99:1 in wastewater, 1.40 mmol Cu²âº could be recovered with 143.78 J electricity outputs, while 50.68 J electricity was input for 0.32 mmol nickel reduction. The total energy output of copper recovery was far more than the electricity input of nickel reduction. The present technology provides a potential method for heavy metal ion separation and recovery.


Assuntos
Cobre/isolamento & purificação , Níquel/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Cátions , Eletricidade , Técnicas Eletroquímicas/instrumentação , Eletrodos , Eliminação de Resíduos Líquidos/instrumentação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação
17.
Chem Commun (Camb) ; 50(76): 11188-91, 2014 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-25110896

RESUMO

Nickel foam supported Zn-Co hydroxide nanoflakes were fabricated by a facile solvothermal method. Benefited from the unique structure of Zn-Co hydroxide nanoflakes on a nickel foam substrate, the as prepared materials exhibited an excellent specific capacitance of 901 F g(-1) at 5 A g(-1) and remarkable cycling stability as electrode materials in supercapacitors.


Assuntos
Cobalto/química , Capacitância Elétrica , Técnicas Eletroquímicas , Hidróxidos/química , Nanopartículas/química , Níquel/química , Zinco/química , Eletrodos , Tamanho da Partícula , Propriedades de Superfície
18.
J Biol Chem ; 289(33): 22850-22864, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24993821

RESUMO

Rapid tumor growth can establish metabolically stressed microenvironments that activate 5'-AMP-activated protein kinase (AMPK), a ubiquitous regulator of ATP homeostasis. Previously, we investigated the importance of AMPK for the growth of experimental tumors prepared from HRAS-transformed mouse embryo fibroblasts and for primary brain tumor development in a rat model of neurocarcinogenesis. Here, we used triple-negative human breast cancer cells in which AMPK activity had been knocked down to investigate the contribution of AMPK to experimental tumor growth and core glucose metabolism. We found that AMPK supports the growth of fast-growing orthotopic tumors prepared from MDA-MB-231 and DU4475 breast cancer cells but had no effect on the proliferation or survival of these cells in culture. We used in vitro and in vivo metabolic profiling with [(13)C]glucose tracers to investigate the contribution of AMPK to core glucose metabolism in MDA-MB-231 cells, which have a Warburg metabolic phenotype; these experiments indicated that AMPK supports tumor glucose metabolism in part through positive regulation of glycolysis and the nonoxidative pentose phosphate cycle. We also found that AMPK activity in the MDA-MB-231 tumors could systemically perturb glucose homeostasis in sensitive normal tissues (liver and pancreas). Overall, our findings suggest that the contribution of AMPK to the growth of aggressive experimental tumors has a critical microenvironmental component that involves specific regulation of core glucose metabolism.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias da Mama/enzimologia , Proteínas de Neoplasias/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Glucose/genética , Glucose/metabolismo , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Via de Pentose Fosfato/genética , Ratos
19.
Chemistry ; 19(46): 15467-71, 2013 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24127220

RESUMO

Magnetize your chemistry! A facile hydrothermal synthetic route was developed for the synthesis of uniform NiS2 hollow spheres, which could be transformed into NiSe2 and NiTe2 hollow spheres through a chemical conversion process. Furthermore, NiS and NiO hollow spheres could be selectively obtained by calcination of NiS2 hollow spheres at different temperatures.

20.
J Pept Sci ; 18(7): 476-86, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22641352

RESUMO

How to target cancer cells with high specificity and kill cancer cells with high efficiency remains an urgent demand for anticancer drugs. Temporin-La, which belongs to the family of temporins, presents antitumor activity against many cancer cell lines. We first used a whole bioinformatic analysis method as a platform to identify new anticancer antimicrobial peptides (AMPs). On the basis of these results, we designed a temporin-La analog (temporin-Las) and related constructs containing the Arg-Gly-Asp (RGD) tripeptide, the integrin αvß3 homing domain (RGD-La and RGD-Las). We detected a link between the net charges and integrin αvß3 expression of cancer cell lines and the antitumor activities of these peptides. Temporin-La and its synthetic analogs inhibited cancer cell proliferation in a dose-dependent manner. Evidence was provided that the affinity between RGD-Las and tumor cell membranes was stronger than other tested peptides using a pull-down assay. Morphological changes on the cell membrane induced by temporin-La and RDG-Las, respectively, were examined by scanning electron microscopy. Additionally, time-dependent morphological changes were detected by confocal microscopy, where the binding process of RGD-Las to the cell membrane could be monitored. The results indicate that the electrostatic interaction between these cationic peptides and the anionic cell membrane is a major determinant of selective cell killing. Thus, the RGD tripeptide is a valuable ligand motif for tumor targeting, which leads to an increased anticancer efficiency by RGD-Las. These AMP-derived peptides have clinical potential as specifically targeting agents for the treatment of αvß3 positive tumors.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Desenho de Fármacos , Integrina alfaVbeta3/química , Oligopeptídeos/farmacologia , Proteínas/farmacologia , Peptídeos Catiônicos Antimicrobianos , Antineoplásicos/síntese química , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Biologia Computacional , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Integrina alfaVbeta3/biossíntese , Integrina alfaVbeta3/metabolismo , Modelos Moleculares , Oligopeptídeos/síntese química , Oligopeptídeos/química , Estrutura Terciária de Proteína/efeitos dos fármacos , Proteínas/síntese química , Proteínas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
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