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1.
Food Chem ; 372: 131305, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34653777

RESUMO

High internal phase emulsions (HIPEs) show promising application in food and cosmetic industries. In this work, diacylglycerol (DAG) was applied to fabricate water-in-oil (W/O) HIPEs. DAG-based emulsion can hold 60% water and the emulsion rigidity increased with water content, indicating the water droplets acted as "active fillers". Stable HIPE with 80% water fraction was formed through the combination of 6 wt% DAG with 1 wt% polyglycerol polyricinoleate (PGPR). The addition of 1 w% kappa (κ)-carrageenan and 0.5 M NaCl greatly reduced the droplet size and enhanced emulsion rigidity, and the interfacial tension of the internal phase was reduced. Benefiting from the Pickering crystals-stabilized interface by DAG as revealed by the microscopy and enhanced elastic modulus of emulsions with the gelation agents, the HIPEs demonstrated good retaining ability for anthocyanin and ß-carotene. This study provides insights for the development of W/O HIPEs to fabricate low-calories margarines, spread or cosmetic creams.

2.
Chemosphere ; 286(Pt 1): 131683, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34351278

RESUMO

Butachlor being an important member of chloroacetanilide herbicides, is frequently used in agriculture to control unwanted weeds. Exposure to butachlor can induce cancer, human lymphocyte aberration, and immunotoxic effects in animals. The current experimental trial was executed to determine the potential risks of herbicide butachlor to immunotoxicity and its mechanism of adverse effects on the spleen. For this purpose, mice were exposed to 8 mg/kg butachlor for 28 days, and the toxicity of butachlor on the spleen of mice was evaluated. We found that butachlor exposure led to an increase in serum ALB, GLU, TC, TG, and TP and changes in the morphological structure of the spleen of mice. More importantly, results showed that butachlor significantly increased the expression level of ATG-5, decreased the protein expression of LC3B and M-TOR, and significantly decreased the mRNA content of M-TOR and p62. Results revealed that the mRNA contents of APAF-1, CYTC, and CASP-9 related genes were significantly decreased after butachlor treatment. Subsequently, the mRNA levels of inflammatory cytokines (IL-1ß, TNF-α, IL-10) were reduced in the spleen of treated mice. This study suggested that butachlor induce spleen toxicity and activate the immune response of spleen tissue by targeting the CYTC/BCL2/M-TOR pathway and caspase cascading activation of spleen autophagy and apoptosis pathways which may ultimately lead to immune system disorders.


Assuntos
Herbicidas , Acetanilidas , Animais , Apoptose , Autofagia , Herbicidas/toxicidade , Camundongos , Baço
3.
Toxicology ; 462: 152957, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34537261

RESUMO

Zearalenone (ZEN), a mycotoxin is frequently detected in different food products and has been widely studied for its toxicity. However, the underlying mechanisms of hepatotoxic effects, relationship between gut microbiome and liver metabolite mediated hepatotoxicity mechanisms induced by ZEN are still not clear. Here, we reported that the different microscopic changes like swelling of hepatocyte, disorganization of hepatocytes and extensive vacuolar degeneration were observed, and the mitochondrial functions decreased in exposed mice. Results exhibited up-regulation in expression of signals of apoptosis and autophagy in liver of treated mice via mitochondrial apoptotic and autophagy pathway (Beclin1/p62). The diversity of gut microbiome decreased and the values of various microbiome altered in treated mice, including 5 phyla (Chloroflexi, Sva0485, Methylomirabilota, MBNT15 and Kryptonia) and genera (Frankia, Lactococcus, Anaerolinea, Halomonas and Sh765B-TzT-35) significantly changed. Liver metabolism showed that the concentrations of 91 metabolite including lipids and lipid like molecules were significantly changed. The values of phosphatidylcholine, 2-Lysophosphatidylcholine and phosphatidate concentrations suggestive of abnormal glycerophosphate metabolism pathway were significantly increased in mice due to exposure to ZEN. In conclusion, the findings suggest that the disorders in gut microbiome and liver metabolites due to exposure to ZEN in mice may affect the liver.

4.
Ecotoxicol Environ Saf ; 224: 112662, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34411823

RESUMO

Fluorine being a well-known and essential element for normal physiological functions of tissues of different organisms is frequently used for growth and development of body. The mechanisms of adverse and injurious impacts of fluoride are not clear and still are under debate. Therefore, this study was executed to ascertain the potential mechanisms of sodium fluoride in liver tissues of ducks. For this purpose, a total of 14 ducks were randomly divided and kept in two groups including control group and sodium fluoride treated group. The ducks in control group were fed with normal diet while the ducks in other group were exposed to sodium fluoride (750 mg/kg) for 28 days. The results showed that exposure to sodium fluoride induced deleterious effects in different liver tissues of ducks. The results indicated that mRNA levels of Cas-3, Cas-9, p53, Apaf-1, Bax and Cyt-c were increased in treated ducks with significantly higher mRNA level of Cas-9 and lower levels of the mRNA level of Bcl-2 as compared to untreated control group (P < 0.01). The results showed that protein expression levels of Bax and p53 were increased while protein expression level of Bcl-2 was reduced in treated ducks. No difference was observed in protein expression level of Cas-3 between treated and untreated ducks. The results of this study suggest that sodium fluoride damages the normal structure of liver and induces abnormal process of apoptosis in hepatocyte, which provide a new idea for elucidating the mechanisms of sodium fluoride induced hepatotoxicity in ducks.

5.
Toxicology ; 461: 152906, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34450209

RESUMO

Fluoride is one of the most widely distributed elements in nature, while some fluorine-containing compounds are toxic to several vertebrates at certain levels. The current study was performed to evaluate the nephrotoxic effects of fluoride exposure in ducks. The results showed that the renal index was decreased in NaF group, and fluoride exposure significantly decreased the levels of serum Albumin, Glucose, Total cholesterol, Urea, protein and Triglycerides, confirming that NaF exhibited adverse effects on the kidney. The overall structure of renal cells showed damage with the signs of nuclelytic, vacuolar degeneration, atrophy, renal cystic cavity widening after fluoride induction. Renal vascular growth was impaired as the expression of VEGF and HIF-1α decreased (p > 0.05). More importantly, autophagy and apoptosis levels of CYT C, LC3, p62, Beclin, M-TOR, Bax and Caspase-3 were increased (p < 0.05) in the NaF treated group. Interestingly, our results showed that Phosphatidylethanolamine (PE) and Phosphatidylcholine (PC) activated the M-TOR autophagy pathway. Meanwhile, the PE acted on Atg5/ LC3 autophagy factor, followed by the auto-phagosome generation and activation of cell autophagy. These results indicate that NaF exposure to duck induced nephron-toxicity by activating autophagy, apoptosis and glucolipid metabolism pathways, which suggest that fluorine exposure poses a risk of poisoning.

6.
Chemosphere ; 283: 131226, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34146870

RESUMO

Butachlor is a systemic herbicide widely applied on wheat, rice, beans, and different other crops, and is frequently detected in groundwater, surface water, and soil. Therefore, it is necessary to investigate the potential adverse health risks and the underlying mechanisms of hepatotoxicity caused by exposure to butachlor in invertebrates, other nontarget animals, and public health. For this reason, a total of 20 mice were obtained and randomly divided into two groups. The experimental mice in one group were exposed to butachlor (8 mg/kg) and the mice in control group received normal saline. The liver tissues were obtained from each mice at day 21 of the trial. Results indicated that exposure to butachlor induced hepatotoxicity in terms of swelling of hepatocyte, disorders in the arrangement of hepatic cells, increased concentrations of different serum enzymes such as alkaline phosphate (ALP) and aspartate aminotransferase (AST). The results on the mechanisms of liver toxicity indicated that butachlor induced overexpression of Apaf-1, Bax, Caspase-3, Caspase-9, Cyt-c, p53, Beclin-1, ATG-5, and LC3, whereas decreases the expression of Bcl-2 and p62 suggesting abnormal processes of apoptosis and autophagy. Results on different metabolites (61 differential metabolites) revealed upregulation of PE and LysoPC, whereas downregulation of SM caused by butachlor exposure in mice led to the disruption of glycerophospholipids and lipid metabolism in the liver. The results of our experimental research indicated that butachlor induces hepatotoxic effects through disruption of lipid metabolism, abnormal mechanisms of autophagy, and apoptosis that provides new insights into the elucidation of the mechanisms of hepatotoxicity in mice induced by butachlor.


Assuntos
Herbicidas , Acetanilidas/toxicidade , Animais , Herbicidas/toxicidade , Metabolismo dos Lipídeos , Fígado , Camundongos
7.
J Acquir Immune Defic Syndr ; 87(2): 763-768, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33534274

RESUMO

ABSTRACT: Before the introduction of highly active antiretroviral therapy, patients infected with HIV experienced poor prognosis including high rates of opportunistic infections, rapid progression to AIDS, and significant mortality. Increased life expectancy after therapeutic improvements has led to an increase in other chronic diseases for these patients, including cardiovascular disease and, in particular, end-stage heart failure. Historically, HIV infection was deemed an absolute contraindication for transplantation. Since the development of highly active antiretroviral therapy, however, life expectancy for HIV-positive patients has significantly improved. In addition, there is a low incidence of opportunistic infections and the current antiretrovirals have an improved toxicity profile. Despite this, the current status of cardiac transplants in HIV-positive patients remains unclear. With this in mind, we conducted a narrative review on cardiac transplantation in patients with HIV.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Insuficiência Cardíaca/cirurgia , Transplante de Coração/métodos , Adulto , Feminino , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Inibidores de Integrase/uso terapêutico , Expectativa de Vida , Masculino , Pessoa de Meia-Idade , Inibidores de Proteases/uso terapêutico
8.
Langmuir ; 37(6): 2195-2204, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33533622

RESUMO

Multi-yolk-shell MnO@mesoporous carbon (MnO@m-carbon) nanopomegranates, featuring MnO nanoparticles within cavities of m-carbon with internal space between the MnO nanoparticle and a cavity carbon shell, were subtly constructed. Moreover, the buffer space was well controlled by means of regulating the size of the cavity in m-carbon or the content of MnO. The results of electrochemical measurements demonstrated that MnO(10)@m-carbon(22) nanopomegranates (MnO nanoparticle, 15 nm; cavity size, 22 nm) had the best cycling and rate performance for lithium ion storage. The pomegranate-like MnO@m-carbon nanostructures have shown several advantages for their excellent performance: the nanocavity in m-carbon can restrict the growth and agglomeration of MnO nanoparticles; the well-interconnected mesoporous carbon matrix provides a "highway" for electrons and lithium ion transport; the voids between the MnO nanoparticle and cavity shell can alleviate the volume expansion.

9.
Sci Rep ; 10(1): 19236, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33159112

RESUMO

The pipeline easily gets corroded in a seawater environment. The oxygen in the seawater is one of major parameters causing the corrosion. In practice, the corrosion due to the oxygen concentration difference, i.e. differential concentration corrosion (DCC), cannot be avoided. However, a one-dimensional DCC model cannot satisfactorily predict the corrosion because the oxygen distribution near the pipe wall is two-dimensional. In this regard, a two-dimensional DCC model was proposed in this study to numerically investigate the distribution of corrosion potential and current in the ionic conductive layer near the pipe wall as well as the overall corrosion current. The results show that DCC plays a significant role in determining the corrosion potential and current. Without considering DCC, a large corrosion potential and current exist at the location with high oxygen concentration near the pipe wall, whereas the occurrence of the low corrosion potential and current corresponds to the location with low oxygen concentration. However, as DCC is considered, at the location with high corrosion potential, cathodic polarization was produced and the corrosion rate decreases; at the location with low corrosion potential, anodic polarization was produced and the corrosion rate increases. In general, the corrosion potential can be homogenized in terms of DCC.

10.
Biomater Sci ; 7(10): 4131-4141, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31328742

RESUMO

Bacterial infection and the issue of antibiotic resistance have become one of the major public health problems worldwide. Thus, searching for new antibacterial agents is urgently required. Hydrogen peroxide, H2O2, as a traditional bactericide, is applied widely for medical treatments. However, the relatively high concentration of H2O2 used in a clinical setting usually inhibits wound healing and even damages normal tissues during disinfection. Here, we synthesized N-doped sponge-like carbon spheres (N-SCSs), which showed excellent mimicking activities for multiple enzymes, including peroxidase, oxidase, superoxide dismutase, and catalase. We then utilized the peroxidase-like activity of the N-SCSs to convert low-concentration H2O2 into radical oxygen species to resist bacteria. The data showed that the antibacterial performance of H2O2 against Gram-negative bacteria (Escherichia coli), Gram-positive bacteria (Staphylococcus aureus), and multidrug-resistant bacteria was improved through the peroxidase-like catalytic reaction of N-SCSs. Importantly, besides generating heat against bacteria, near-infrared laser exposure also promoted the peroxidase activity of N-SCSs, to further generate radical oxygen species to kill bacteria. In addition, this catalytic-photothermal antibacterial strategy demonstrated accelerated recovery of infected wounds in an animal model. Thus, our work provides a new synergetic anti-infection strategy, and further expands the application of carbon-based nanozymes in biomedicine.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Carbono/química , Luz , Catálise , Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos da radiação , Peróxido de Hidrogênio/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/efeitos da radiação
11.
Chem Commun (Camb) ; 55(56): 8064-8067, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31237580

RESUMO

A new class of pomegranate-like multicore-shell Mn3O4 encapsulated mesoporous N-doped carbon nanospheres (m-N-C@Mn3O4) with an internal void space has been developed. The novel nanostructure of m-N-C@Mn3O4 nanopomegranates has been proven to significantly alleviate the volume change and improve the electronic conductivity, which endows lithium-ion batteries with superior rate performance and cycling stability.

12.
J Electrocardiol ; 51(6): 939-940, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30497751

RESUMO

An otherwise healthy 64-year-old man with recently diagnosed multiple myeloma was admitted to hospital with hypercalcemia and renal failure. Despite his electrocardiogram showing short QT/QTc intervals, he was admitted without cardiac monitoring. He died suddenly a few hours later, likely from a fatal arrhythmia. This case illustrates that pronounced QT shortening from hypercalcemia is an underappreciated malignant finding that can portend a significant risk for arrhythmia and sudden cardiac death. In addition, we also discuss the causes of hypercalcemia associated short QT/QTc intervals and its ECG features.


Assuntos
Morte Súbita Cardíaca/etiologia , Eletrocardiografia , Hipercalcemia/complicações , Mieloma Múltiplo/complicações , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade
14.
J Thorac Imaging ; 31(6): 373-379, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27753753

RESUMO

BACKGROUND: Coronary computed tomography (CT) angiography (CCTA) has the ability to detect, characterize, and quantify atherosclerotic plaques. The aim of our study was to evaluate the prognostic power of CCTA-quantified plaque subtypes. MATERIALS AND METHODS: A total of 36 patients with adverse events and 36 Morise score-matched patients who remained event free on follow-up were identified. Using CCTA images, plaque subtype volumes in the major epicardial arteries were analyzed using predetermined attenuation ranges in Hounsfield units (HU): 1 to 30 HU (low attenuating), 31 to 70 HU (intermediate attenuating), 71 to 150 HU (high attenuating), and mean coronary lumen+2 SD to 1000 HU (calcified). Each epicardial artery was divided into proximal, mid, and distal segments, and plaque volumes were normalized for arterial segment length. RESULTS: The baseline characteristics of the 2 cohorts were similar. Low-attenuation and intermediate-attenuation plaque volumes were greater in the proximal segments as well as in the entire length in the adverse event compared with the event-free group. High-attenuation plaque volume was increased only in the proximal segments in the adverse event group. There was no difference in the volume of calcified plaque between the 2 groups. The log rank test using a cutoff of 3.99 mm/mm for combined intermediate and low plaque volume showed more adverse events in patients with a plaque volume of ≥3.99 mm/mm. CONCLUSIONS: Adverse events appear to be associated with greater volumes of low-attenuation and intermediate-attenuation plaques that reflect lipid and fibrous atherosclerosis. The difference between the 2 groups is most apparent in the proximal epicardial arteries.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prognóstico
15.
Int J Gynecol Cancer ; 25(7): 1173-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26270118

RESUMO

OBJECTIVE: This work aims to explore whether Toll-like receptor 9 (TLR9) -1486T/C and 2848G/A polymorphisms are associated with cervical cancer risk. METHODS: A comprehensive electronic search of studies published from January 1999 to October 2014 was conducted in Medline (Ovid), Embase, PubMed, Wanfang, Weipu, and CNKI. The algorithm included "TLR," "Toll-like receptor," "polymorphism," "variant," "mutation," and "cervical cancer." Seven articles, including 9 studies, were pooled using Revman 5.2 (Cochrane Collaboration, Copenhagen, Denmark). Odds ratio (OR) was used to explore the involvement of minor allele C (C vs T and CC + CT vs TT) of TLR9 (-1486T/C, rs187084) and minor allele A (A vs G and AA + AG vs GG) of TLR9 (2848G/A, rs352140) in cervical cancer risk. RESULTS: Toll-like receptor 9 (-1486T/C, rs187084) polymorphisms were associated with an elevated risk of cervical cancer (C vs T: OR, 1.15; 95% confidence interval [CI], 1.03-1.29; CC + CT vs TT: OR, 1.30; 95% CI, 1.11-1.53). We found no significant association between TLR9 (2848G/A, rs352140) polymorphisms and cervical cancer risk (A vs G: OR, 1.15; 95% CI, 0.87-1.54; AA + AG vs GG: OR, 1.27; 95% CI, 0.75-2.17). CONCLUSIONS: This meta-analysis indicates that TLR9 (-1486T/C, rs187084)-but not TLR9 (2848G/A, rs352140)-may be a risk factor for cervical cancer.


Assuntos
Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Receptor Toll-Like 9/genética , Neoplasias do Colo do Útero/genética , Feminino , Genótipo , Humanos , Metanálise como Assunto , Prognóstico , Fatores de Risco
16.
Cardiovasc Diagn Ther ; 5(1): 71-3, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25774352

RESUMO

Coronary computed tomography angiography (CCTA) is an emerging modality for comprehensive non-invasive assessment of coronary artery disease (CAD). CCTA was traditionally used for anatomical assessment of coronary plaque, including luminal narrowing, plaque burden, location, and composition. Preliminary studies have also demonstrated CCTA's capabilities for functional assessment of coronary plaque, including fractional flow reserve (FFR) and myocardial perfusion-albeit they are not routinely available at all centers and are focus of research. Although the identification and development of treatment strategies of severely stenotic lesions has advanced tremendously over the past years, the evaluation, prognostication, and treatment of patients with intermediate severity stenosis in whom there is equipoise between invasive versus medical management is only now receiving attention. Intermediate severity stenosis is the most likely to benefit from additional measures of disease beyond traditional clinical risk profiling and CCTA visual examination. Nakazato et al. studied 58 patients with intermediate severity stenosis and quantified the percent aggregate plaque volume (%APV), a novel measure of total arterial plaque disease. %APV had the highest correlation with ischemic lesions on FFR, outperforming luminal diameter, luminal area, minimal lumen diameter, and minimal lumen area. This study extracts additional information from pre-existing CT data-sets and suggest novel concept that might improve classification of moderate severity coronary stenoses.

17.
Bioengineered ; 5(4): 269­73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24911584

RESUMO

Recombinant glycoprotein drugs require proper glycosylation for optimal therapeutic efficacy. Glycoprotein therapeutics are rapidly removed from circulation and have reduced efficacy if they are poorly sialylated. Ricinus communis agglutinin-I (RCA-I) was found highly toxic to wild-type CHO-K1 cells and all the mutants that survived RCA-I treatment contained a dysfunctional N-acetylglucosaminyltransferase I (GnT I) gene. These mutants are named CHO-gmt4 cells. Interestingly, upon restoration of GnT I, the sialylation of a model glycoprotein, erythropoietin, produced in CHO-gmt4 cells was shown to be superior to that produced in wild-type CHO-K1 cells. This addendum summarizes the applicability of this cell line, from transient to stable expression of the recombinant protein, and from a lab scale to an industrial scale perfusion bioreactor. In addition, CHO-gmt4 cells can be used to produce glycoproteins with mannose-terminated N-glycans. Recombinant glucocerebrosidase produced by CHO-gmt4 cells will not require glycan remodeling and may be directly used to treat patients with Gaucher disease. CHO-gmt4 cells can also be used to produce other glycoprotein therapeutics which target cells expressing mannose receptors.


Assuntos
Engenharia Celular , Eritropoetina/genética , Eritropoetina/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Tetra-Hidrofolato Desidrogenase/genética , Animais , Humanos
18.
Biotechnol Lett ; 36(5): 907-11, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24557070

RESUMO

Sodium butyrate is commonly used in mammalian cell cultures to increase the productivity of recombinant proteins. A Chinese hamster ovary (CHO) cell line producing recombinant human erythropoietin (rhEPO) was cultured in commercial medium. Addition of 0.5 mM butyrate inhibited the over-growth of the cells after the medium was changed from serum-added medium to serum-free medium. At the 6th day, the addition of butyrate lowered the transcriptional level of sialidases I, II, and III compared to that of control groups by 56, 87, and 59%, respectively. Extracellular sialidase activity was decreased by 53% by addition of butyrate. The inhibition of cell over-growth and the decrease of extracellular sialidase activity helped to increase the acidic isoform content of rhEPO expressed by this CHO cell strain.


Assuntos
Ácido Butírico/farmacologia , Técnicas de Cultura de Células/métodos , Eritropoetina/metabolismo , Animais , Biotecnologia , Células CHO , Cricetinae , Cricetulus , Eritropoetina/análise , Eritropoetina/química , Eritropoetina/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Isoformas de Proteínas/análise , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/análise , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
19.
Biotechnol J ; 9(1): 100-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24166780

RESUMO

Therapeutic glycoprotein drugs require a high degree of sialylation of their N-glycans for a better circulatory half-life that results in greater efficacy. It has been demonstrated that Chinese hamster ovary (CHO) glycosylation mutants lacking N-acetylglucosaminyltransferase I (GnT I), when restored by introduction of a functional GnT I, produced highly sialylated erythropoietin (EPO). We have now further engineered one of such mutants, JW152, by inactivating the dihydrofolate reductase (DHFR) gene to allow for the amplification of the EPO gene with methotrexate (MTX). Several MTX-amplified clones maintained the ability to produce highly sialylated EPO and one was selected for culture in a perfusion bioreactor that is used in an existing industrial EPO-production bioprocess. Extensive characterization of the EPO produced was performed using total sialic quantification, HPAEC-PAD and MALDI-TOF MS analyses. Our results demonstrated that the EPO produced by the mutant line exhibits superior sialylation compared to the commercially used EPO-producing CHO clone cultured under the same conditions. Therefore, this mutant has the industrial potential for producing highly sialylated recombinant EPO and potentially other recombinant glycoprotein therapeutics.


Assuntos
Engenharia Celular , Eritropoetina/genética , Eritropoetina/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Tetra-Hidrofolato Desidrogenase/genética , Animais , Reatores Biológicos , Células CHO , Cricetinae , Cricetulus , Eritropoetina/química , Amplificação de Genes/efeitos dos fármacos , Glicosilação , Meia-Vida , Humanos , Metotrexato/farmacologia , Mutação , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tetra-Hidrofolato Desidrogenase/metabolismo
20.
PLoS One ; 8(11): e78417, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24223801

RESUMO

RhoB, a member of small GTPases belonging to the Ras protein superfamily, might have a suppressive activity in cancer progression. Here, expression of RhoB gene was evaluated in human benign, borderline and malignant ovary tumors by immunostaining, with normal ovary tissue as control. Malignant tumors were assessed according to Federation Internationale de Gynecologie Obstetrique (FIGO) guidelines and classified in stage I-IV. Revivification of RhoB gene was investigated by analyzing the effect of histone deacetylase (HDAC) inhibitor trichostatin (TSA) and methyltransferase inhibitor 5-azacytidine (5-Aza) on ovarian cancer cells via RT-PCR and western blot. Apoptosis of ovary cancer cells was detected using flowcytometry and fluorescence microscopy. Subsequently, RhoB expression is detected in normal ovary epithelium, borderline tumors, and decreases significantly or lost in the majority of ovarian cancer specimen (P<0.05). RhoB expression decreases significantly from stage II (71.4%) to stage III (43.5%) to stage IV (18.2%, P<0.05). TSA can both significantly revive the RhoB gene and mediate apoptosis of ovarian cancer cells, but 5-Aza couldn't. Interference into Revivification of RhoB gene results in reduction of ovary carcinoma cell apoptosis. It is proposed that loss of RhoB expression occurs frequently in ovary carcinogenesis and progression and its expression could be regulated by histone deacetylation but not by promoter hypermethylation, which may serve as a prospective gene treatment target for the patients with ovarian malignancy not responding to standard therapies.


Assuntos
Carcinogênese/genética , Cistadenoma Seroso/genética , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/genética , Neoplasias Ovarianas/genética , Proteína rhoB de Ligação ao GTP/genética , Antineoplásicos/farmacologia , Azacitidina/farmacologia , Carcinogênese/metabolismo , Carcinogênese/patologia , Estudos de Casos e Controles , Cistadenoma Seroso/metabolismo , Cistadenoma Seroso/patologia , Metilação de DNA , DNA de Neoplasias/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Metiltransferases/genética , Metiltransferases/metabolismo , Estadiamento de Neoplasias , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Ovário/metabolismo , Ovário/patologia , Proteína rhoB de Ligação ao GTP/metabolismo
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