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1.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36834898

RESUMO

The identification of the prognostic markers and therapeutic targets might benefit the diagnosis and treatment of pancreatic adenocarcinoma (PAAD), one of the most aggressive malignancies. Vacuolar protein sorting associated protein 26 A (VPS26A) is a candidate prognosis gene for hepatocellular carcinoma, but its expression and function in PAAD remain unknown. The mRNA and protein expression of VPS26A in PAAD was explored and validated by bioinformatics and immunohistochemical analysis. The correlation between VPS26A expression and various clinical parameters, genetic status, diagnostic and prognostic value, survival and immune infiltration were evaluated, and the co-expressed gene-set enrichment analysis for VPS26A was performed. Cytologic and molecular experiments were further carried out to investigate the role and potential mechanism of VPS26A in PAAD. The mRNA and protein levels of VPS26A were elevated in PAAD tissues. High VPS26A expression was associated with the advanced histological type, tumor stage simplified, smoking status and tumor mutational burden score, and the poor prognosis of PAAD patients. VPS26A expression was significantly correlated with immune infiltration and immunotherapy response. VPS26A-co-expressed genes were mainly enriched in the regulation of cell adhesion and actin cytoskeleton and the immune-response-regulating signaling pathway. Our experiments further demonstrated that VPS26A promoted the proliferation, migration and invasion potentials of PAAD cell lines through activating the EGFR/ERK signaling. Our study suggested that VPS26A could be a potential biomarker and a therapeutic target for PAAD through comprehensive regulation of its growth, migration and immune microenvironment.


Assuntos
Adenocarcinoma , Neoplasias Hepáticas , Neoplasias Pancreáticas , Humanos , Regulação Neoplásica da Expressão Gênica , Prognóstico , Microambiente Tumoral , Neoplasias Pancreáticas
2.
Water Sci Technol ; 87(4): 924-937, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36853771

RESUMO

The diverse compositions and complex nature of the textile wastewater make it imperative to find an economical and suitable degradation pathway. The degradation of real textile wastewater on a novel heterogeneous electro-Fenton system was carried out with a composite anode of magnetically fixed micron ZVI coupling with a Ti/RuO2-IrO2 sheet. The influences of different variables such as mZVI dosage, H2O2 amount, applied voltage and pH value on both total organic carbon and chemical oxygen demand removal efficiencies and energy consumption were investigated. The optimized parameters were simultaneously verified by using electrochemical workstation Tafel curves and Nyquist plots. The optimal operating conditions for evaluating the wastewater treatment were H2O2 dosage of 0.10 mol·L-1, applied voltage of 5.0 V, mZVI amount of 1.0 g·L-1 and initial pH value of 3.0. The high TOC and COD removal efficiencies of 92.44 and 82.84% could be achieved simultaneously in 60 min, respectively. XRD, XPS and SEM-EDS were used to investigate the interaction between the pollutant and the mZVI. GC-MS analysis was performed on untreated and treated wastewater to determine the degradation of pollutants in dyeing wastewater during the electro-Fenton process and to effectively propose a suitable degradation mechanism for this system.


Assuntos
Poluentes Ambientais , Peróxido de Hidrogênio , Pós , Águas Residuárias , Eletrodos , Têxteis
3.
Water Sci Technol ; 84(1): 216-224, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34280165

RESUMO

This study shows the effectiveness of a novel electrocoagulation process using magnetically attracted iron scrap anodes for phosphate removal from aqueous solution. The effect of contact time, reaction temperature, dose of iron scrap, initial phosphate concentration, applied voltage, pH, magnetic force, and the species of competing anions on the efficiency of phosphate removal and the reaction products has been investigated. The techniques of XRD, XPS, and VSM were used to characterize the elemental composition and the types of the reaction products in order to clarify the interaction between novel anode and phosphate ions. The removal of phosphate was fitted by a pseudo first-order reaction kinetic model. The results showed that magnetically attracted iron scrap anodes were electrodissoluted under an applied potential and reacted with phosphate into Fe-hydroxo-phosphate complexes. The work suggested that electrocoagulation using magnetically attracted iron scrap anodes had the potential to become a promising technique for phosphate precipitation.


Assuntos
Ferro , Poluentes Químicos da Água , Eletrocoagulação , Eletrodos , Concentração de Íons de Hidrogênio , Fosfatos
4.
Cancers (Basel) ; 16(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38254825

RESUMO

Pancreatic cancer (PC) is an aggressive and fatal malignant tumor, and exosomes have been reported to be closely related to PC invasion and metastasis. Here we found that Exo70, a key subunit of the exocyst complex, promoted PC metastasis by regulating the secretion of tumor exosomes. Clinical sample studies showed that Exo70 was highly expressed in PC and negatively correlated with patients' survival. Exo70 promoted PC cell lines' invasion and migration. Interestingly, knockdown of Exo70, or using an Exo70 inhibitor (ES2) inhibited the secretion of tumor exosomes and increased the accumulation of cellular vesicles. Furthermore, Exo70 was found to accumulate in the exosomes, which then fused with neighboring PC cells and promoted their invasion. Moreover, Exo70 increased the expression of exosomal PD-L1, leading to the immune escape of PC cells. In vivo, knockdown of Exo70 or treatment with ES2 both decreased the tumor metastasis of PC cells in mice. This study provides new insight into the mechanism of invasion and metastasis in PC and identifies Exo70 as a potential prognostic factor and therapeutic target for PC.

5.
ACS Omega ; 8(14): 12707-12715, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37065085

RESUMO

This study presents an economic and environmentally friendly method for the synthesis of microspherical FePO4·2H2O precursors with secondary nanostructures by the electroflocculation of low-cost iron fillers in a hot solution. The morphology and crystalline shape of the precursors were adjusted by gradient co-precipitation of pH conditions. The effect of precursor structure and morphology on the electrochemical performance of the synthesized LiFePO4/C was investigated. Electrochemical analysis showed that the assembly of FePO4·2H2O submicron spherical particles from primary nanoparticles and nanorods resulted in LiFePO4/C exhibiting excellent multiplicity and cycling performance with first discharge capacities at 0.2C, 1C, 5C, and 10C of 162.8, 134.7, 85.5, and 47.7 mAh·g-1, respectively, and the capacity of LiFePO4/C was maintained at 85.5% after 300 cycles at 1C. The significant improvement in the electrochemical performance of LiFePO4/C was attributed to the enhanced Li+ diffusion rate and the crystallinity of LiFePO4/C. Thus, this work shows a new three-dimensional mesoporous FePO4 synthesized from the iron flake electroflocculation as a precursor for high-performance LiFePO4/C cathodes for lithium-ion batteries.

6.
JHEP Rep ; 5(11): 100883, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37860052

RESUMO

Background & Aims: HBV infection is one of the leading causes of liver cirrhosis. However, the immune microenvironment in patients with HBV cirrhosis remains elusive. Methods: Single-cell RNA sequencing was used to analyse the transcriptomes of 76,210 immune cells in the livers of six healthy individuals and in five patients with HBV cirrhosis. Results: Patients with HBV cirrhosis have a unique immune ecosystem characterised by an accumulation of macrophage-CD9/IL18, macrophage-C1QA, NK Cell-JUNB, CD4+ T cell-IL7R, and a loss of B cell-IGLC1 clusters. Furthermore, our analysis predicted enhanced cell communication between myeloid cells and all immune cells in patients with HBV-related cirrhosis. Pseudo-time analysis of myeloid cells, natural killer (NK) cells, and B cells demonstrated a significant accumulation of mature cells and a depletion of naive cells in HBV cirrhosis. In addition, we observed an increase in antigen processing and presentation capacities in myeloid cells in patients with HBV cirrhosis, whereas NK cell-mediated cytotoxicity was substantially reduced. Conclusions: Our results provide valuable insight into the immune landscape of HBV cirrhosis, suggesting that HBV cirrhosis is associated with the accumulation of activated myeloid cells and impaired cytotoxicity in NK cells. Impact and implications: The absence of single-cell transcriptome profiling of immune cells in HBV cirrhosis hinders our understanding of the underlying mechanisms driving disease progression. To address this knowledge gap, our study unveils a distinctive immune ecosystem in HBV cirrhosis and represents a crucial advancement in elucidating the impact of the immune milieu on the development of this condition. These findings constitute significant strides towards the identification of more effective therapeutic approaches for HBV cirrhosis and are relevant for healthcare professionals, researchers, and pharmaceutical developers dedicated to combating this disease.

7.
Front Immunol ; 14: 1320414, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38116005

RESUMO

Introduction: Immune cells play crucial roles in the development of chronic hepatitis B virus (HBV) infection, leading to cirrhosis and hepatocellular carcinoma (HCC). However, their functions at different disease stages are not fully understood. Methods: In this study, we used single-cell RNA sequencing (scRNA-seq) to characterize the human liver immune microenvironment at different disease stages. We analyzed scRNA-seq data from 118,455 immune cells obtained from livers of six healthy individuals, four patients with HBV infection, five patients with HBV cirrhosis, and three patients with HBV-associated HCC. Results: Our results showed an accumulation of scar-associated macrophages during disease progression, and we identified two relevant immune subsets, Macrophage-CD9/IL18 and macrophage-CD9/IFI6. Macrophage-CD9/IL18 expanded from HBV infection to cirrhosis, while macrophage-CD9/IFI6 expanded from cirrhosis to HCC. We verified the existence of Macrophage-CD9/IFI6 using multiplex immunofluorescence staining. We also found an increase in cytotoxic NK Cell-GNLY during progression from cirrhosis to HCC. Additionally, the proportion of CD4 T cell-TNFAIP3, CD8 T cell-TNF (effector CD8 T cells), and CD8 T cell-CD53 increased, while the proportion of Treg cells decreased from HBV infection to cirrhosis. The proportion of Treg and CD8 T cell-LAG3 (Exhausted CD8 T cell) enhanced, while the proportion of CD8 T cell-TNF (effector CD8 T cells) decreased from cirrhosis to HCC. Furthermore, GSEA enrichment analyses revealed that MAPK, ERBB, and P53 signaling pathways in myeloid cells were gradually inhibited from HBV infection to cirrhosis and HCC. Discussion: Our study provides important insights into changes in the hepatic immune environment during the progression of HBV-related liver disease, which may help improve the management of HBV-infected liver diseases.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Hepatite B , Neoplasias Hepáticas , Humanos , Vírus da Hepatite B , Interleucina-18 , Hepatite B/complicações , Cirrose Hepática/complicações , Microambiente Tumoral
8.
Chemosphere ; 294: 133806, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35120957

RESUMO

Ammonium as the major reduction intermediate has always been the limitation of nitrate reduction by cathodic reduction or nano zero-valent iron (nZVI). In this work, we report the electrochemical nitrate removal by magnetically immobilized nZVI anode on RuO2-IrO2/Ti plate with ammonia-oxidizing function. This system shows maximum nitrate removal efficiency of 94.6% and nitrogen selectivity up to 72.8% at pH of 3.0, and it has also high nitrate removal efficiency (90.2%) and nitrogen selectivity (70.6%) near neutral medium (pH = 6). As the increase of the applied anodic potentials, both nitrate removal efficiency (from 27.2% to 94.6%) and nitrogen selectivity (70.4%-72.8%) increase. The incorpration of RuO2-IrO2/Ti plate with ammonia-oxidizing function on the nZVI anode enhances the nitrate reduction. The dosage of nZVI on RuO2-IrO2/Ti plate (from 0.2 g to 0.6 g) has a slight effect (the variance is no more than 10.0%) on the removal performance. Cyclic voltammetry, Tafel analysis and electrochemical impedance spectroscopy (EIS) were further used to investigate the reaction mechanisms occurring on the nZVI surfaces in terms of CV curve area, corrosion voltage, corrosion current density and charge-transfer resistance. In conclusion, high nitrate removal performance of magnetically immobilized nZVI anode coupled with RuO2-IrO2/Ti plate may guide the design of improved electrochemical reduction by nZVI-based anode for practical nitrate remediation.


Assuntos
Nitratos , Poluentes Químicos da Água , Amônia/análise , Eletrodos , Ferro/química , Nitratos/química , Oxirredução , Titânio/análise , Poluentes Químicos da Água/análise
9.
Cancers (Basel) ; 14(10)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35626097

RESUMO

Antiangiogenic therapy is an important treatment strategy for metastatic colorectal cancer (mCRC). We carried out a clinical study of low-dose apatinib (250 mg) monotherapy as a third-line treatment in patients with mCRC and assessed its efficacy and safety. It demonstrated that low-dose apatinib had comparable survival outcomes, significantly improved the patient quality of life, and caused tolerable adverse reactions. To further investigate the underlying mechanism of the effects of apatinib in CRC besides angiogenesis, we performed RNA-seq, and our results suggested that apatinib may have other potential antitumor mechanisms in CRC through multiple pathways, including exosomes secretion. In RKO and HCT116 cells, apatinib significantly reduced exosomes secretion by targeting multivesicular body (MVB) transport. Further studies have indicated that apatinib not only promoted the degradation of MVBs via the regulation of LAMP2 but also interfered with MVB transport by inhibiting Rab11 expression. Moreover, apatinib inhibited MVB membrane fusion by reducing SNAP23 and VAMP2 expression. In vivo, apatinib inhibited orthotopic murine colon cancer growth and metastasis and reduced the serum exosomes amount. This novel regulatory mechanism provides a new perspective for the antitumor effect of apatinib beyond angiogenesis inhibition.

10.
Phytomedicine ; 94: 153843, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34785414

RESUMO

BACKGROUND: Obesity is the cause of multiple metabolic disorders, and its incidence has been rapidly increasing worldwide. It develops when energy intake exceeds energy expenditure (EE). Wedelolactone (WDL) is a naturally isolated compound from Eclipta prostrata L. and possesses many pharmacological activities. However, little is known about the effect of WDL on obesity and EE. PURPOSE: The present study aimed to investigate the effect of WDL on obesity and EE in diet-induced obese (DIO) mice and its underlying mechanism. METHODS: Obese mice were induced by high fat diet. The effects of WDL on obese mice were assessed by examining body weight, fat mass, EE, glucose tolerance, and hepatic and kidney injury. 3T3-L1 cells were differentiated into mature adipocytes and incubated with WDL in vitro. Immunohistochemistry, western blotting, and real-time PCR were used to assess adipose browning. The inhibitory efficiency of WDL on nicotinamide N-methyltransferase (NNMT) was evaluated using a fluorescence assay. RESULTS: WDL reduced fat mass, suppressed body weight gain, and improved obesity-related metabolic disorders in DIO mice. WDL treatment promoted adipose browning and enhanced EE in both DIO mice and 3T3-L1 cells. These effects were eliminated in AMPK antagonized or PPARα knockdown cells and in PPARα-/- mice. Furthermore, we identified the target of WDL to be NNMT, an appealing target for regulating energy metabolism. WDL inhibited NNMT with an extremely low IC50 of 0.03 µM. Inhibition of NNMT and activation of SIRT1/AMPK/PPARα explains how WDL reverses obesity by prompting adipose browning. CONCLUSION: Our findings demonstrate the novel effects of WDL in promoting adipose browning, enhancing EE and attenuating obesity and uncover the underlying mechanism, which includes inhibition of NNMT and subsequently activation of SIRT1/AMPK/PPARα in response to WDL. WDL could be further developed as a therapeutic agent for treating obesity and related metabolic diseases.


Assuntos
Nicotinamida N-Metiltransferase , Sirtuína 1 , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP , Animais , Cumarínicos , Dieta Hiperlipídica , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , PPAR alfa , Compostos Fitoquímicos
11.
Cancer Lett ; 531: 27-38, 2022 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-35093426

RESUMO

In vivo tumor growth is characterized by a necrotic core generated by oxygen and nutrients gradients, which is replicated by in vitro three-dimensional (3D) tumor spheroids but not traditional two-dimensional cell monolayers. Gap junctions provide direct communication between adjacent cells and play a critical role in cancer development, but their effects are still debatable. In this study, we found that connexin 43 (Cx43) reduced the area of necrotic core in colon cancer 3D spheroids, thus providing a growth advantage. This impact is dependent on gap junction channel functions, as the channel blocker carbenoxolone or connexin channel death mutant reverses this effect. Additionally, enhanced glucose uptake was detected in Cx43-overexpressing spheroids, along with upregulated mTOR, downregulated AMPK signaling, increased ATP content, and enhanced oxygen consumption rate. Furthermore, the xenograft mouse model confirmed the growth advantage of Cx43 in vivo. RNAseq data and clinical information from The Cancer Genome Atlas (TCGA) database indicated a more heterogeneous expression pattern of Cx43 in colon cancer compared to normal colon tissue, and higher Cx43 level is associated with worse clinical outcomes. Our data suggest a novel function of connexin in tumor growth, that gap junctions may provide nutrients transmitting routes in lieu of vasculature to meet the increasing metabolic requirement of solid tumors.


Assuntos
Neoplasias do Colo , Conexina 43 , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Conexinas/genética , Conexinas/metabolismo , Junções Comunicantes/metabolismo , Glucose/metabolismo , Humanos , Camundongos
12.
Anesth Analg ; 112(5): 1088-95, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21415436

RESUMO

BACKGROUND: General anesthetics (e.g., propofol) influence the therapeutic activity of intraoperative radiotherapy but the mechanism of the effects is largely unknown. It has been reported that propofol inhibits gap junction (GJ) function briefly, and a functional GJ enhances the efficacy of radiotherapy in some cancer cells. Yet the mechanisms underlying the inhibition of GJ function by propofol and the influence of propofol on therapeutic activity of intraoperative radiotherapy are unknown. METHODS: The role of propofol at clinically relevant concentrations in the modulation of radiograph-induced cytotoxicity in HeLa cells transfected with connexin 32 (Cx32) plasmid was explored by manipulation of connexin expression, GJ presence, and function. GJ function, Cx32 protein level, and Cx32 mRNA expression were determined by "Parachute" dye-coupling assay, Western blotting, and reverse transcriptase-polymerase chain reaction, respectively. RESULTS: Propofol significantly reduced radiograph-induced cytotoxicity only in the presence of functional GJ. Four-hour propofol exposure inhibited GJ function mainly by diminution of Cx32 protein levels but without influence on Cx32 mRNA expression. CONCLUSIONS: These results suggest that propofol inhibits the function of the GJ through the reduction of Cx32 protein levels by a transcription-independent mechanism. They further indicate that propofol depresses the cytotoxicity of radiograph irradiation through inhibition of GJ activity.


Assuntos
Anestésicos Intravenosos/farmacologia , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/efeitos da radiação , Propofol/farmacologia , Raios X , Western Blotting , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Conexinas/genética , Conexinas/metabolismo , Citoproteção , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Junções Comunicantes/metabolismo , Células HeLa , Humanos , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transfecção , Proteína beta-1 de Junções Comunicantes
13.
Cancer Res ; 81(23): 5904-5918, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34654723

RESUMO

Invasive mucinous lung adenocarcinoma (IMA) is a subtype of lung adenocarcinoma with a strong invasive ability. IMA frequently carries "undruggable" KRAS mutations, highlighting the need for new molecular targets and therapies. Nuclear receptor HNF4α is abnormally enriched in IMA, but the potential of HNF4α to be a therapeutic target for IMA remains unknown. Here, we report that P2 promoter-driven HNF4α expression promotes IMA growth and metastasis. Mechanistically, HNF4α transactivated lncRNA BC200, which acted as a scaffold for mRNA binding protein FMR1. BC200 promoted the ability of FMR1 to bind and regulate stability of cancer-related mRNAs and HNF4α mRNA, forming a positive feedback circuit. Mycophenolic acid, the active metabolite of FDA-approved drug mycophenolate mofetil, was identified as an HNF4α antagonist exhibiting anti-IMA activities in vitro and in vivo. This study reveals the role of a HNF4α-BC200-FMR1-positive feedback loop in promoting mRNA stability during IMA progression and metastasis, providing a targeted therapeutic strategy for IMA. SIGNIFICANCE: Growth and metastatic progression of invasive mucinous lung adenocarcinoma can be restricted by targeting HNF4α, a critical regulator of a BC200-FMR1-mRNA stability axis.


Assuntos
Adenocarcinoma de Pulmão/secundário , Adenocarcinoma Mucinoso/secundário , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Regulação Neoplásica da Expressão Gênica , Fator 4 Nuclear de Hepatócito/metabolismo , Neoplasias Pulmonares/patologia , RNA Longo não Codificante/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Retroalimentação Fisiológica , Feminino , Proteína do X Frágil da Deficiência Intelectual/genética , Fator 4 Nuclear de Hepatócito/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Cancers (Basel) ; 13(14)2021 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-34298686

RESUMO

Whilst researches elucidating a diversity of intracellular mechanisms, platinum-resistant epithelial ovarian cancer (EOC) remains a major challenge in the treatment of ovarian cancer. Here we report that Exo70, a key subunit of the exocyst complex, contributes to both innate and acquired cisplatin resistance of EOC. Upregulation of Exo70 is observed in EOC tissues and is related to platinum resistance and progression-free survival of EOC patients. Exo70 suppressed the cisplatin sensitivity of EOC cells through promoting exocytosis-mediated efflux of cisplatin. Moreover, cisplatin-induced autophagy-lysosomal degradation of Exo70 protein by modulating phosphorylation of AMPK and mTOR, thereby reducing the cellular resistance. However, the function was hampered during prolonged cisplatin treatment, which in turn stabilized Exo70 to facilitate the acquired cisplatin resistance of EOC cells. Knockdown of Exo70, or inhibiting exocytosis by Exo70 inhibitor Endosidin2, reversed the cisplatin resistance of EOC cells both in vitro and in vivo. Our results suggest that Exo70 overexpression and excessive stability contribute to innate and acquired cisplatin resistance through the increase in cisplatin efflux, and targeting Exo70 might be an approach to overcome cisplatin resistance in EOC treatment.

15.
J Pharmacol Exp Ther ; 333(3): 903-11, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20215407

RESUMO

Cisplatin [cis-diamminedichloroplatinum(II)]/oxaliplatin [1,2-diamminocyclohexane(trans-1)oxolatoplatinum(II)] toxicity is enhanced by functional gap junctions between treated cells, implying that inhibition of gap junctions may decrease cytotoxic activity of these platinum-based agents. This study investigates the effect of gap junction modulation by cisplatin/oxaliplatin on cytotoxicity in a transformed cell line. The effects were explored using junctional channels expressed in transfected HeLa cells and purified hemichannels. Junctional channels showed a rapid, dose-dependent decrease in dye coupling with exposure to cisplatin/oxaliplatin. With longer exposure, both compounds also decreased connexin expression. Both compounds inhibit the activity of purified connexin hemichannels, over the same concentration range that they inhibit junctional dye permeability, demonstrating that inhibition occurs by direct interaction of the drugs with connexin protein. Cisplatin/oxaliplatin reduced the clonogenic survival of HeLa cells at low density and high density in a dose-dependent manner, but to a greater degree at high density, consistent with a positive effect of gap junctional intercellular communication (GJIC) on cytotoxicity. Reduction of GJIC by genetic or pharmacological means decreased cisplatin/oxaliplatin toxicity. At low cisplatin/oxaliplatin concentrations, where effects on connexin channels are minimal, the toxicity increased with increased cell density. However, higher concentrations strongly inhibited GJIC, and this counteracted the enhancing effect of greater cell density on toxicity. The present results indicate that inhibition of GJIC by cisplatin/oxaliplatin decreases their cytotoxicity. Direct inhibition of GJIC and reduction of connexin expression by cisplatin/oxaliplatin may thereby compromise the effectiveness of these compounds and be a factor in the development of resistance to this class of chemotherapeutic agents.


Assuntos
Antineoplásicos/farmacologia , Comunicação Celular/efeitos dos fármacos , Cisplatino/farmacologia , Conexinas/biossíntese , Junções Comunicantes/efeitos dos fármacos , Compostos Organoplatínicos/farmacologia , Transporte Biológico Ativo , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Corantes , Conexinas/antagonistas & inibidores , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Lipossomos/química , Oxaliplatina
16.
IEEE Trans Vis Comput Graph ; 26(3): 1442-1453, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30295622

RESUMO

Given the expanding use of 3D Objects in a variety of fields such as animation, gaming, virtual worlds, commerce, augmented reality and 3D printing, we present a novel system for object browsing and searching. Specifically, the system packs objects into an interactive 3D cloud for browsing and searching. It was designed with the aim of increasing search efficiency in a variety of active environments, while providing a visually engaging layout, and we evaluated this by conducting a comparative user study. We show that our system can significantly decrease search times compared to the classic grid-based layout, and it has been suggested by subjects that cloud-based searching is more interesting and visually-engaging.

17.
Water Res ; 169: 115239, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31706129

RESUMO

Electro-oxidation using RuO2-IrO2/Ti plate anode and electrocoagulation using iron plate anode were widely applied to remove ammonia and phosphate in an aquatic environment, respectively. In this work, we designed magnetically bound ZVI microparticles on RuO2-IrO2/Ti plate as a composite electrode for the simultaneous removal of ammonia and phosphate from aqueous solution via combined EO and EC (EO/EC) processes. We present a series of experiments to study such simultaneous removal under an electric field via the EO/EC process. In the electrochemical unit, mZVI-RuO2-IrO2/Ti, mZVI-graphite, and RuO2-IrO2/Ti electrodes were used as anodes. The influence of applied voltage, initial pH, zero-valent iron dosage, reaction temperature, and organic compounds on the EO/EC process was also examined. Ammonia and phosphate could be completely removed at an applied voltage of 10 V, pH of 7, zero-valent iron dosage of 0.1 g, and reaction temperature of 35 °C using mZVI-RuO2-IrO2/Ti anode when influent ammonia and phosphate concentrations is 200 and 100 mg L-1. Ammonia degradation was consistent with pseudo-zero-order kinetic model. The characterization was analyzed by scanning electron microscope-energy dispersive spectrometer (SEM-EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Hence, the mZVI-RuO2-IrO2/Ti electrode can be used for efficient simultaneous removal of ammonia and phosphate.


Assuntos
Amônia , Poluentes Químicos da Água , Eletrocoagulação , Eletrodos , Ferro , Oxirredução , Fosfatos
18.
J Hazard Mater ; 388: 121768, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31843409

RESUMO

This study combined electro-oxidation (EO) and electrocoagulation (EC) process (EO/EC) to treat landfill leachate by using RuO2-IrO2/Ti plate and microscale zero-valent iron powder composite anode. EO was achieved by direct oxidation and indirect oxidation on RuO2-IrO2/Ti plate, whereas EC was achieved using iron powder to lose electrons and produce coagulants in situ. The influences of variables including type of anode material, applied voltage, zero-valent iron dosage, interelectrode gap, and reaction temperature on EO/EC were evaluated. Results showed that at an applied voltage of 10 V, zero-valent iron dosage of 0.2 g, interelectrode gap of 1 cm, and non-temperature-controlled mode, the removal efficiencies were 72.5 % for total organic carbon (TOC), 98.5 % for ammonia, and 98.6 % for total phosphorus (TP). Some heavy metals and hardness were also removed. Further analysis indicated that the removal of TOC, ammonia, and TP followed pseudo-first order, pseudo-zero order, and pseudo-second order kinetic models, respectively. Other characteristics were examined by scanning electron microscopy-energy dispersive spectrometry, X-ray diffraction, and X-ray photoelectron spectroscopy. Overall, our results showed that EO/EC can be used to efficiently remove organic matter, ammonia, TP, and heavy metals from landfill leachate.

19.
J Med Chem ; 63(11): 5841-5855, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32391701

RESUMO

We reported recently that berberine (Ber), a traditional oriental medicine to treat gastroenteritis, binds and activates retinoid X receptor α (RXRα) for suppressing the growth of colon cancer cells. Here, we extended our studies based on the binding mode of Ber with RXRα by design, synthesis, and biological evaluation of a focused library of 15 novel Ber analogues. Among them, 3,9-dimethoxy-5,6-dihydroisoquinolino[3,2-a]isoquinolin-7-ium chloride (B-12) was identified as the optimal RXRα activator. More efficiently than Ber, B-12 bound and altered the conformation of RXRα/LBD, thereby suppressing the Wnt/ß-catenin pathway and colon cancer cell growth via RXRα mediation. In addition, B-12 not only preserved Ber's tumor selectivity but also greatly improved its bioavailability. Remarkably, in mice, B-12 did not show obvious side effects including hypertriglyceridemia as other RXRα agonists or induce hepatorenal toxicity. Together, our study describes an approach for the rational design of Ber-derived RXRα activators as novel effective antineoplastic agents for colon cancer.


Assuntos
Antineoplásicos/química , Berberina/análogos & derivados , Receptor X Retinoide alfa/agonistas , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Berberina/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Humanos , Masculino , Camundongos , Camundongos Nus , Simulação de Acoplamento Molecular , Estrutura Terciária de Proteína , Ratos , Receptor X Retinoide alfa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Transplante Heterólogo
20.
Nat Commun ; 11(1): 117, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913283

RESUMO

Increased expression of protein kinase ULK1 was reported to negatively correlate with breast cancer metastasis. Here we report that ULK1 suppresses the migration and invasion of human breast cancer cells. The suppressive effect is mediated through direct phosphorylation of Exo70, a key component of the exocyst complex. ULK1 phosphorylation inhibits Exo70 homo-oligomerization as well as its assembly to the exocyst complex, which are needed for cell protrusion formation and matrix metalloproteinases secretion during cell invasion. Reversely, upon growth factor stimulation, Exo70 is phosphorylated by ERK1/2, which in turn suppresses its phosphorylation by ULK1. Together, our study identifies Exo70 as a substrate of ULK1 that inhibits cancer metastasis, and demonstrates that two counteractive regulatory mechanisms are well orchestrated during tumor cell invasion.


Assuntos
Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Neoplasias da Mama/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Nus , Metástase Neoplásica , Fosforilação , Proteínas de Transporte Vesicular/genética
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