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2.
Commun Biol ; 4(1): 1335, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34824369

RESUMO

DNA phosphorothioation (PT) is widely distributed in the human gut microbiome. In this work, PT-diet effect on nematodes was studied with PT-bioengineering bacteria. We found that the ROS level decreased by about 20-50% and the age-related lipofuscin accumulation was reduced by 15-25%. Moreover, the PT-feeding worms were more active at all life periods, and more resistant to acute stressors. Intriguingly, their lifespans were prolonged by ~21.7%. Comparative RNA-seq analysis indicated that many gene expressions were dramatically regulated by PT-diet, such as cysteine-rich protein (scl-11/12/13), sulfur-related enzyme (cpr-2), longevity gene (jnk-1) and stress response (sod-3/5, gps-5/6, gst-18/20, hsp-12.8). Both the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis suggested that neuroactivity pathways were upregulated, while phosphoryl transfer and DNA-repair pathways were down-regulated in good-appetite young worms. The findings pave the way for pro-longevity of multicellular organisms by PT-bacterial interference.


Assuntos
Caenorhabditis elegans/fisiologia , DNA Bacteriano/metabolismo , Fosfatos/metabolismo , Espécies Reativas de Oxigênio , Animais , DNA Bacteriano/administração & dosagem , Locomoção/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Fosfatos/administração & dosagem
3.
Biochem Mol Biol Educ ; 46(6): 644-651, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30387293

RESUMO

Laboratory exercises focused on protein quantification are frequently conducted in traditional undergraduate biochemistry laboratory curriculum. The laboratory course described here is designed to provide students with experience in measurement of protein content in milk powder by moving reaction boundary titration (MRBT), a new rapid technique for total protein content determination in milk. In addition, this approach is weakly influenced by nonprotein nitrogen reagents such as melamine and urea. The course was done as three weekly laboratory exercises. First, students established a standard curve for milk protein concentration by MRBT method. Then, students investigated the influence of nonprotein nitrogen reagents on MRBT method. Finally, students made a comparison among three different protein quantification methods (MRBT, Biuret, and Kjeldahl method). From the experiments, students grasped the concept and advantages of MRBT and deepened the understanding of protein quantification. This course offer students the opportunity to be exposed to an advanced technique, which may have practical significance to their future study and work in the life science field. © 2018 International Union of Biochemistry and Molecular Biology, 46(6):644-651, 2018.


Assuntos
Bioquímica/educação , Currículo , Laboratórios , Proteínas do Leite/análise , Leite/química , Titulometria/métodos , Universidades , Animais , Humanos , Pós/química , Estudantes
4.
Biomacromolecules ; 18(7): 2102-2117, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28605176

RESUMO

The organoiridium(III) complex (Ir(III)) [(η5-Cpxbiph)Ir(phpy) (py)]PF6 containing π-bonded biphenyltetramethylcyclopentadienyl(Cpxbiph), C∧N-chelated phenylpyridine(phpy), and pyridine (py) ligands has more potent antitumor activity as a new generation of drug than cisplatin toward various cancer cells. However, poor site-specific delivery, low solubility, and poor tumor penetration are common limitations of chemotherapy drugs. To develop CD44-targetable, pH-, and reduction-responsive drug delivery systems for Ir(III) drugs, the amphiphilic hyaluronan (HA)-based conjugates of HA-cystamin-pyrenyl (HA-ss-Py) containing disulfide bonds and HA-pyrenyl (HA-Py) were designed. The Ir(III) drug was readily loaded into these two amphiphilic conjugates and nanoparticles were formed. Dynamic light scattering (DLS) studies showed that the micelles formed from HA-ss-Py were sufficiently stable under physiological conditions, but were prone to rapid dissociation in reducing environments (20 mM glutathione (GSH)). In subsequent confocal microscopy analyses, A549 cancer cells efficiently internalized HA-based micelles. Moreover, in vitro cytotoxicity assays in A549 cells demonstrat that Ir-loaded HA-based nanoparticles have higher cytotoxicity than the free Ir(III) anticancer drug. Finally, systemic administration of Ir(III)-loaded HA-ss-Py nanoparticles enhanced tumor inhibition in vivo, and the corresponding biodistribution experiments showed that HA-ss-Py micelles accumulate in tumors. Overall, our results suggest that HA-ss-Py micelles have a great potential to be used as an effective Ir(III) drug carrier for targeted cancer therapy.


Assuntos
Antineoplásicos , Ácido Hialurônico , Irídio , Neoplasias/tratamento farmacológico , Compostos Organometálicos , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Concentração de Íons de Hidrogênio , Irídio/química , Irídio/farmacologia , Neoplasias/metabolismo , Neoplasias/patologia , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia
5.
Biomacromolecules ; 18(6): 1677-1696, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28485601

RESUMO

Nanomaterials, including gold, silver, and magnetic nanoparticles, carbon, and mesoporous materials, possess unique physiochemical and biological properties, thus offering promising applications in biomedicine, such as in drug delivery, biosensing, molecular imaging, and therapy. Recent advances in nanotechnology have improved the features and properties of nanomaterials. However, these nanomaterials are potentially cytotoxic and demonstrate a lack of cell-specific function. Thus, they have been functionalized with various polymers, especially polysaccharides, to reduce toxicity and improve biocompatibility and stability under physiological conditions. In particular, nanomaterials have been widely functionalized with hyaluronan (HA) to enhance their distribution in specific cells and tissues. This review highlights the most recent advances on HA-functionalized nanomaterials for biotechnological and biomedical applications, as nanocarriers in drug delivery, contrast agents in molecular imaging, and diagnostic agents in cancer therapy. A critical evaluation of barriers affecting the use of HA-functionalized nanomaterials is also discussed, and insights into the outlook of the field are explored.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Ácido Hialurônico/química , Nanopartículas de Magnetita/química , Nanoestruturas/química , Materiais Biocompatíveis/síntese química , Técnicas Biossensoriais , Carbono/química , Meios de Contraste/síntese química , Ouro/química , Humanos , Nanopartículas de Magnetita/ultraestrutura , Imagem Molecular , Nanoestruturas/ultraestrutura , Polissacarídeos/química , Prata/química
6.
Electrophoresis ; 38(13-14): 1706-1712, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28306175

RESUMO

Moving reaction boundary titration (MRBT) has a potential application to immunoassay and protein content analysis with high selectivity. However, air bubbles often impair the accuracy of MRBT, and the leakage of electrolyte greatly decreases the safety and convenience of electrophoretic titration. Addressing these two issues a reliable MRBT device with modified electrolyte chamber of protein titration was designed. Multiphysics computer simulation was conducted for optimization according to two-phase flow. The single chamber was made of two perpendicular cylinders with different diameters. After placing electrophoretic tube, the resident air in the junction next to the gel could be eliminated by a simple fast electrolyte flow. Removing the electrophoretic tube automatically prevented electrolyte leakage at the junction due to the gravity-induced negative pressure within the chamber. Moreover, the numerical simulation and experiments showed that the improved MRBT device has following advantages: (i) easy and rapid setup of electrophoretic tube within 20 s; (ii) simple and quick bubble dissipates from the chamber of titration within 2 s; (iii) no electrolyte leakage from the two chambers: and (iv) accurate protein titration and safe instrumental operation. The developed technique and apparatus greatly improves the performance of the previous MRBT device, and providing a new route toward practical application.


Assuntos
Eletroforese/instrumentação , Eletroforese/métodos , Proteínas/análise , Proteínas/química , Simulação por Computador , Desenho de Equipamento
7.
Cancer Lett ; 366(1): 100-11, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26095601

RESUMO

Radiation induced normal tissue damage is the most important limitation for the delivery of a high potentially curative radiation dose. Genistein (GEN), one of the main soy isoflavone components, has drawn wide attention for its bioactivity in alleviating radiation damage. However, the effects and molecular mechanisms underlying the radioprotective effects of GEN remain unclear. In the present study, we showed that low concentration of GEN (1.5 µM) protected L-02 cells against radiation damage via inhibition of apoptosis, alleviation of DNA damage and chromosome aberration, down-regulation of GRP78 and up-regulation of HERP, HUS1 and hHR23A. In contrast, high concentration of GEN (20 µM) demonstrated radiosensitizing characteristics through the promotion of apoptosis and chromosome aberration, impairment of DNA repair, up-regulation of GRP78, and down-regulation of HUS1, SIRT1, RAD17, RAD51 and RNF8. These findings shed light on using low, but not high-concentration GEN, as a potential candidate for adjuvant therapy to alleviate radiation-induced injuries to human recipients of ionizing radiation.


Assuntos
Apoptose/efeitos dos fármacos , Dano ao DNA , Genisteína/farmacologia , Protetores contra Radiação/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Aberrações Cromossômicas , Enzimas Reparadoras do DNA/genética , Proteínas de Ligação a DNA/genética , Relação Dose-Resposta à Radiação , Proteínas de Choque Térmico/genética , Humanos , Proteínas de Membrana/genética , Raios X
8.
Appl Microbiol Biotechnol ; 98(10): 4399-407, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24522728

RESUMO

Lavendamycin methyl ester (LME) is a derivative of a highly functionalized aminoquinone alkaloid lavendamycin and could be used as a scaffold for novel anticancer agent development. This work demonstrated LME production by cultivation of an engineered strain of Streptomyces flocculus CGMCC4.1223 ΔstnB1, while the wild-type strain did not produce. To enhance its production, the effect of shear stress and oxygen supply on ΔstnB1 strain cultivation was investigated in detail. In flask culture, when the shaking speed increased from 150 to 220 rpm, the mycelium was altered from a large pellet to a filamentous hypha, and the LME production was almost doubled, while no significant differences were observed among varied filling volumes, which implied a crucial role of shear stress in the morphology and LME production. To confirm this suggestion, experiments with agitation speed ranging from 400 to 1,000 rpm at a fixed aeration rate of 1.0 vvm were conducted in a stirred tank bioreactor. It was found that the morphology became more hairy with reduced pellet size, and the LME production was enhanced threefolds when the agitation speed increased from 400 to 800 rpm. Further experiments by varying initial k L a value at the same agitation speed indicated that oxygen supply only slightly affected the physiological status of ΔstnB1 strain. Altogether, shear stress was identified as a major factor affecting the cell morphology and LME production. The work would be helpful to the production of LME and other secondary metabolites by filamentous microorganism cultivation.


Assuntos
Antibióticos Antineoplásicos/metabolismo , Streptomyces/citologia , Streptomyces/metabolismo , Estreptonigrina/análogos & derivados , Estresse Mecânico , Fenômenos Mecânicos , Oxigênio/metabolismo , Streptomyces/genética , Streptomyces/fisiologia , Estreptonigrina/metabolismo
9.
Nanotechnology ; 24(23): 235706, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-23673609

RESUMO

In this paper, we demonstrate that ZnxCd1-xSe nanomultipods can be synthesized via a facile and nontoxic solution-based method. Interesting aspects of composition, morphology and optical properties were deeply explored. The value of Zn/(Zn+Cd) could be altered across the entire range from 0.08 to 0.86 by varying the ratio of cation precursor contents. The band gap energy could be linearly tuned from 1.88 to 2.48 eV with respect to the value of Zn/(Zn+Cd). The experiment also showed that oleylamine played a dominant role in the formation of multipod structure. A possible growth mechanism was further suggested. First-principles calculations of band gap energy and density of states in the Vienna ab initio simulation package code were performed to verify the experimental variation tendency of the band gap. Computational results indicated that dissimilarities of electronic band structures and orbital constitutions determined the tunable band gap of the as-synthesized nanomultipod, which might be promising for versatile applications in relevant areas of solar cells, biomedicine, sensors, catalysts and so on.


Assuntos
Cádmio/química , Nanopartículas/química , Selênio/química , Zinco/química , Compostos de Cádmio/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Compostos de Selênio/química , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Difração de Raios X
10.
Biomed Rep ; 1(1): 139-143, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24648910

RESUMO

ß-1,3-1,6-glucans are the most abundant glucose polymers in the cell walls of fungi. Previous studies have shown that ß-1,3-1,6-glucans derived from fungi possess immunomodulating activitivies. Antitumor effects of these compounds have also been reported in animal models. Current studies mainly focus on the direct effects of ß-1,3-1,6-glucans on immune systems, but no data are available to address the underlying molecular events in tumor cells. ß-1,3-1,6-glucan purified from black yeast at 5 mg/100 g body weight (study group) or saline (control group) was intragastrically administered on a daily basis to subcutaneously-injected mice with mouse S180 sarcoma cells. Tumor sizes, tumor weights, serum concentrations of cytokines and levels of microRNAs (miRNAs) in transplanted tumors were compared between the treated and control groups. The volumes and weights of transplanted tumors were significantly lower in the treatment groups compared to the control groups by ∼150% and 70%, respectively. The treated mice demonstrated significantly higher levels of cytokines, including IL-2, IL-4, IL-6, IL-8, IL-10 and IL-12, compared to the control mice. Notably, the expression of several miRNAs in transplanted tumor tissues also markedly changed. These data suggest that black yeast-derived ß-1,3-1,6-glucan, not only stimulates cytokine release from immune cells, but also changes the expression profiles of miRNAs in transplanted tumors.

11.
Exp Ther Med ; 1(2): 277-283, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22993540

RESUMO

To investigate the in vivo and in vitro inhibitory effects of deuterium-depleted water (DDW) on human lung cancer and the possible mechanisms underlying these effects, we cultured and treated human lung carcinoma cell line A549 and human embryonic lung fibroblasts HLF-1 with various concentrations of DDW from 2 to 72 h. Cellular growth inhibition rates were determined using the 3-(4, 5-dimethyldiazol-2-yl)-2, 5-diphenyltetrazolium-bromide) (MTT) proliferation assay. A549 cells were treated with 50±5 ppm DDW, and the morphology and structure of cells were observed by scanning electron microscopy (SEM). We observed alterations in the cellular skeleton by transmission electron microscopy (TEM) and changes in cell cycle by flow cytometry. Our data showed that DDW significantly inhibited the proliferation of A549 cells at a specific time point, and cells demonstrated the characteristic morphological changes of apoptosis under SEM and TEM. The length of the S phase increased significantly in cells treated with 50 ppm DDW, whereas the G0 to G1 phase and G2 to M phase were decreased. We observed DDW-induced cellular apoptosis using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and DNA fragment analyses. In addition, we established a tumor transplantion model by injecting H460 tumor cells into subcutaneous tissue of BALB/c mice treated with DDW for 60 days. We determined the tumor inhibition rate of treated and control groups and found that the tumor weight was significantly decreased and the tumor inhibition rate was approximately 30% in the DDW group. We conclude that DDW is a promising new anticancer agent with potential for future clinical application.

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