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1.
J Nanosci Nanotechnol ; 20(2): 1098-1108, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383110

RESUMO

In this study, the 2D porous graphitic carbon nitride (g-C3N4) nanosheets were successfully fabricated via a facile thermal decomposition polymerization method without any help of templates, and then novel porous g-C3N4/CdS complex catalysts of different mass fractions were is situ synthesized by a simple solvothermal process. The results of photocatalytic experiments demonstrate that the coupling g-C3N4/CdS cocatalysts exhibit significant enhanced visible-light-driven photocatalytic activity for the decolorization of methyl orange (MO) compared with individual porous g-C3N4 and CdS. In particular, an optimal porous g-C3N4 content in the hybridized composite has been determined to be 70 wt.%, corresponding to pseudo-first-order rate constant of 0.046 min-1, which is 7 and 11 times faster than that of pure porous g-C3N4 and CdS, respectively. Photoluminescence (PL) spectroscopy measurements clearly confirmed that the recombination of photoproduced electrons and holes in g-C3N4/CdS composites was efficiently inhibited due to the formation of heterojunctions. Furthermore, the possible mechanism of enhanced photocatalytic activity and photostability of prous g-C3N4/CdS are also tentatively proposed.

2.
Chemosphere ; 239: 124703, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31526999

RESUMO

In recent years, precise environment supervision has gradually become vital in water pollution control, which requires the clear identification of dissolved organic matters (DOM) in wastewater. Metalworking fluid (MWF) is a type of wastewater with high toxicity. Over ten million m3 of MWF is discharged per year. However, its DOM characteristics have not yet been systematically investigated. Therefore, in this study, the fluorescent DOM (FDOM) of MWF was firstly characterized by excitation-emission matrix-parallel factor analysis (EEM-PARAFAC) and high-performance liquid chromatography (HPLC). Three fluorescent components (C1-C3) of the MWF from three metalworking plants (BO, TH, and YD) were identified. The peaks measured for C1 and C3 were attributed to tryptophan-like (Peak T) and humic/fulvic acid-like (Peak A + C) peaks, respectively, and the peaks at C2 were identified as humic-like (Peak A + M) or tryptophan-like (Peak T) peaks. There were differences in the C2 and C3 components of MWF from the three metalworking plants. The FDOM of MWF from the three metalworking plants exhibited similar polarity, but different apparent molecular weight distributions. In addition, the highest intensities of the three fluorescent peaks were sensitive to variations in the pH, humic acid (HA) concentrations, and metal ion levels (Cu2+, Fe3+, and Ni2+). The findings of this study not only indicate the FDOM characteristics of MWF, but also provide a promising method and valuable guidance for the practical monitoring of MWF in natural water bodies.

3.
Toxicol In Vitro ; 62: 104677, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31629067

RESUMO

Doxorubicin (DOX) has dose-dependent toxicity on ovarian follicles (OFs), and the inhibition of different signaling molecules along with the DOX application for enhancing its efficacy can also upsurge this toxicity. Therefore, it is strongly required to explore the mechanism of DOX-induced toxicity in 3D culture systems for protecting the OFs. A microfluidic chip was used to culture a single OF to identify the potential signaling molecules and their combined effects on OFs dynamically. The chip offers better 3D biomimetic microenvironment to the growing OF than 2D culture systems. The OFs cultured on the chip were treated with DOX and the inhibitors of Src, Ca2+, and PIM. Their mutual effects were studied on OFs growth and 17ß-estradiol secretion. Besides, the RNA levels of B4GALT2 and UNC5C genes of DOX-exposed OFs were detected by RT-qPCR, and TUNEL staining experiments were conducted to check the OF apoptosis. The results showed that DOX application reduced the OFs growth and hormone secretion and induced apoptosis in the OFs. Moreover, the DOX-induced toxic effects were enriched by Src and PIM inhibition, while reduced by the ER-Ca2+ channel inhibitor. This study specifically demonstrates the synergistic effects of some signaling molecules on DOX-mediated cellular functions of OFs and demands some meditative measures to decipher this toxicity for supporting the female endocrine and reproductive functions.

4.
Mar Environ Res ; 152: 104823, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31676169

RESUMO

The oil spill accidents may drastically impact the environment and ecosystem at intertidal zones. The spilled oil will penetrate the sediments and accumulate to cause lethal or sublethal effects on the benthic invertebrates. An M-BACI experiment was manipulated in situ to assess the ecological responses of benthic macrofauna to different degrees of diesel oil spill. Both biotic and abiotic parameters were studied for 126 days, subjected to both "pulse" and "press" oil contaminations. The content of aliphatic hydrocarbons (displayed as ratios of n-C17/Pr and n-C18/Ph) slightly dropped then continuously existed in the sediment during the experiment time. The macrofaunal assemblage structures were dramatically altered in species number, abundance and biomass. In general, it takes longer time for the macrofauna assemblages to recover under high concentration oil spill than that under low concentration. Our results highlight the diversified strategies for survival and recolonization among dominant species, which distinguish themselves between: i) tolerant species, ii) opportunistic species, and iii) equilibrium species.

5.
Sheng Wu Gong Cheng Xue Bao ; 35(10): 1942-1954, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31668040

RESUMO

The chemical manufacturing industry that uses fossil resources as raw materials, consumes non-renewable resources and also causes damage to the ecological environment, stimulating the development of bio-manufacturing with renewable resources as raw materials. Unlike traditional chemical manufacturing, bio-manufacturing uses cells as a "production workshop", and each process in the "workshop" is catalyzed by enzymes. In addition to mild reaction conditions, the "cell factory" has strong plasticity, and can be used to synthesize various target chemicals according to demand adjustment or reconstitution of metabolic pathways. The design process of the "cell factory" follows the following guidelines: 1) Construct an optimal synthetic route from raw materials to products; 2) Balance the metabolic flux of each reaction in the metabolic pathway, so that the metabolic flux of this pathway is much higher than the primary metabolism of the cells; 3) Precursor supply in the pathway should be sufficient, and adjust multiple precursors supply ratio as needed; 4) enzymatic reactions often involve the participation of various cofactors, smooth metabolic pathways need to balance or regenerate various cofactors; 5) Through genetic modification or process improvement to remove metabolic intermediates and products feedback inhibition to achieve higher yields.


Assuntos
Biotecnologia , Células/metabolismo , Engenharia Metabólica , Redes e Vias Metabólicas , Coenzimas/metabolismo , Redes e Vias Metabólicas/genética
6.
Sci Rep ; 9(1): 15733, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673000

RESUMO

State-of-art quantum key distribution (QKD) systems are performed with several GHz pulse rates, meanwhile privacy amplification (PA) with large scale inputs has to be performed to generate the final secure keys with quantified security. In this paper, we propose a fast Fourier transform (FFT) enhanced high-speed and large-scale (HiLS) PA scheme on commercial CPU platform without increasing dedicated computational devices. The long input weak secure key is divided into many blocks and the random seed for constructing Toeplitz matrix is shuffled to multiple sub-sequences respectively, then PA procedures are parallel implemented for all sub-key blocks with correlated sub-sequences, afterwards, the outcomes are merged as the final secure key. When the input scale is 128 Mb, our proposed HiLS PA scheme reaches 71.16 Mbps, 54.08 Mbps and 39.15 Mbps with the compression ratio equals to 0.125, 0.25 and 0.375 respectively, resulting achievable secure key generation rates close to the asymptotic limit. HiLS PA scheme can be applied to 10 GHz QKD systems with even larger input scales and the evaluated throughput is around 32.49 Mbps with the compression ratio equals to 0.125 and the input scale of 1 Gb, which is ten times larger than the previous works for QKD systems. Furthermore, with the limited computational resources, the achieved throughput of HiLS PA scheme is 0.44 Mbps with the compression ratio equals to 0.125, when the input scale equals up to 128 Gb. In theory, the PA of the randomness extraction in quantum random number generation (QRNG) is same as the PA procedure in QKD, and our work can also be efficiently performed in high-speed QRNG.

7.
BMC Cancer ; 19(1): 1064, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703631

RESUMO

BACKGROUND: The present standard of surgical treatment for esophageal cancer is country dependent. The aim of the present study was to investigate the basic aspects of surgical procedures performed for esophageal cancer, and provide information about the present state of esophageal cancer surgery in China. METHODS: Data were obtained from a database administered by the Chinese Ministry for Health. A total of 542 participating hospitals were divided into seven geographic areas, and 10% of hospitals in each area were randomly chosen for inclusion. All patients with esophageal cancer, who underwent esophagectomy in these participating hospitals from January 1 to December 31, 2015, were included in the present study. The clinical characteristics, stage of tumor at diagnosis, operation summary and outcomes, and histological findings of patients were extracted and analyzed. RESULTS: The present study included 11,791 patients, and the average number of patients per hospital was 218. Squamous cell carcinoma was the most common pathological type, while the mid-esophagus was the most common location. Open procedures were performed in 63.8% of patients, while minimally invasive esophagectomy was performed in 36.2% of patients. Multiple approaches to transthoracic esophagectomy were utilized. Two-field lymphadenectomy was the most frequently performed (64.8%), followed by three-field lymphadenectomy (21.8%). Gastric tubes, thoracic duct ligation and postoperative enteral nutrition were implemented to minimize complications. CONCLUSION: The standard operative procedure and detailed technique for esophageal carcinoma surgery is presently being debated in China. This survey provides some basic information about the present state of esophageal cancer surgery countrywide.

8.
Cell Metab ; 30(5): 937-951.e5, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31668872

RESUMO

Obesity-induced adipose dysfunction is a major contributor to atherosclerosis. Cold exposure has been reported to affect atherosclerosis through regulation of adipose function, but the mechanism has not been well clarified. Here, adipocyte hypoxia-inducible factor 2α (HIF-2α) was upregulated after mild cold exposure at 16°C and mediated cold-induced thermogenesis. Adipocyte HIF-2α deficiency exacerbated Western-diet-induced atherosclerosis by increasing adipose ceramide levels, which blunted hepatocyte cholesterol elimination and thermogenesis. Mechanistically, Acer2, the gene encoding alkaline ceramidase 2, was identified as a novel target gene of HIF-2α, triggering ceramide catabolism. Adipose overexpression of ACER2 rescued adipocyte HIF-2α-deficiency-induced exacerbation of atherosclerosis. Furthermore, activation of adipose HIF-2α by the HIF prolyl hydroxylase inhibitor FG-4592 had protective effects on atherosclerosis, accompanied by a reduction in adipose and plasma ceramide and plasma cholesterol levels. This study highlights adipocyte HIF-2α as a putative drug target against atherosclerosis.

10.
Theranostics ; 9(25): 7666-7679, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695793

RESUMO

Despite burgeoning development of nanoplatform made in the past few years, it remains a challenge to produce drug nanocarrier that enables requested on/off drug release. Thus, this study aimed to develop an ideal near-infrared light-triggered smart nanocarrier for targeted imaging-guided treatment of cancer that tactfully integrated photothermal therapy with chemotherapy to accurately control drug release time and dosage. Methods: This delivery system was composed of Ag2S QD coating with dendritic mesoporous silica (DMSN), which acted as nanocarrier of doxorubicin localized inside pores. To provide the nanocarrier with controlled release capability, a polypeptide-engineered that structure was reversible to photothermal effect of Ag2S QD, was covalently grafted to the external surface of drug-loaded DMSN. Results: This nanocarrier with the size of 40~60 nm had satisfactory biocompatibility and photothermal conversion efficiency up to 28.35%. Due to acidity-triggered charge reversal of polypeptide, which significantly extended circulation time and improved targeting ability, fluorescence and photoacoustic signals were still obvious at tumor site post-24 h by tail vein injection and chemo-photothermal synergistic therapy obviously enhanced antitumor efficacy. Mild PTT with multiple short-term exposures not only reduced the side effect of overdose drug but also avoided skin damage caused by long-term irradiation. Conclusion: By adjusting irradiation time and on/off cycle, multiple small amount local drug release reduced the side effect of overdose drug and skin damage. This novel approach provided an ideal near-infrared light-triggered nanocarrier with accurate control of area, time, and especially dosage.

11.
Math Biosci Eng ; 16(6): 6231-6241, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31698559

RESUMO

RNA modification plays an indispensable role in the regulation of organisms. RNA modification site prediction offers an insight into diverse cellular processing. Regarding different types of RNA modification site prediction, it is difficult to tell the most relevant feature combinations from a variant of RNA properties. Thereby, the performance of traditional machine learning based predictors relied on the skill of feature engineering. As a data-driven approach, deep learning can detect optimal feature patterns to represent input data. In this study, we developed a predictor for multiple types of RNA modifications method called DeepMRMP (Multiple Types RNA Modification Sites Predictor), which is based on the bidirectional Gated Recurrent Unit (BGRU) and transfer learning. DeepMRMP makes full use of multiple RNA site modification data and correlation among them to build predictor for different types of RNA modification sites. Through 10-fold cross-validation of the RNA sequences of H. sapiens, M. musculus and S. cerevisiae, DeepMRMP acted as a reliable computational tool for identifying N1-methyladenosine (m1A), pseudouridine (Ψ), 5-methylcytosine (m5C) modification sites.

12.
Math Biosci Eng ; 16(6): 6923-6933, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31698596

RESUMO

Objective: To investigate whether miR-125a-5p can inhibit the proliferation and invasion of breast cancer cells and induce apoptosis by targeting GAB2. Methods: qRT-PCR was used to detect the expression of miR-125a-5p in normal mammary epithelial cells and breast cancer cell lines; The miR-125a-5p overexpression plasmid was transiently transfected into MDA-MB-157 cells, and the proliferation, invasion and apoptosis of breast cancer cells were detected by CCK8 kit, Transwell chamber and flow cytometry, respectively; Gene silencing was used to knock down GAB2 gene in MDA-MB-157 cells, and the changes of proliferation, invasion, apoptosis and apoptosis-related proteins in breast cancer cells were detected by CCK8 kit, Transwell chamber, flow cytometry and western blot, respectively; The direct interaction between miR-125a-5p and GAB2 was detected by dual-luciferase reporter assay. The miR-125a-5p overexpression plasmid was transiently transfected into MDA-MB-157 cells, and the expression levels of GAB2 and apoptosis-related proteins were detected by western blot. Results: The expression of miR-125a-5p in breast cancer cell lines, MDA-MB-157 cells, MDA-MB-361 cells and MDA-MB-415 cells, was significantly lower than that in normal breast epithelial cells, MCF-10A cells; The proliferation and invasion ability of MDA-MB-157 cells transfected with miR-125a-5p were significantly inhibited, and the apoptosis rate was significantly increased; Since GAB2 knocked down, the proliferation and invasion ability of MDA-MB-157 cells were significantly inhibited, while the apoptosis rate was significantly increased, the Bax protein expression was significantly down-regulated, and the Bcl-2 protein expression was significantly up-regulated; The dual-luciferase reporter assay demonstrated that miR-125a-5p can specifically target GAB2. Transfected with miR-125a-5p, the GAB2 protein expression and Bax protein expression were significantly down-regulated, but the Bcl-2 protein expression was significantly up-regulated. Conclusion: miR-125a-5p inhibits the proliferation and invasion of breast cancer cells and induces their apoptosis by negatively regulating GAB2.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31702393

RESUMO

Background: EGFR-AS1 has been characterized as an oncogenic lncRNA in many types of cancers, while its roles in esophageal squamous cell carcinoma (ESCC) are unknown. Results: Their data showed that EGFR-AS1 and ROCK1 were upregulated in ESCC and positively correlated. Survival analysis showed that high EGFR-AS1 and ROCK1 expression levels predicted poor survival. In ESCC cells, EGFR-AS1 overexpression led to upregulated ROCK1, while miR-145 overexpression led to downregulated ROCK1 and reduced effects of EGFR-AS1 overexpression. Bioinformatics analysis showed that miR-145 may bind EGFR-AS1, while overexpression of EGFR-AS1 and miR-145 did not significantly affect each other. In esophageal squamous cell carcinoma (ESCC) cells, EGFR-AS1 and ROCK1 overexpression mediated the increased rates of ECSS cell invasion and migration. Overexpression of miR-145 played an opposite role and attenuated the effects of EGFR-AS1 overexpression. Conclusion: Therefore, EGFR-AS1 may upregulate ROCK1 by sponging miR-145 to promote ESCC cell invasion and migration.

14.
Bioorg Chem ; : 103369, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31703810

RESUMO

2-Epi-jaspine B is an isomer of the natural product jaspine B and shows certain selectivity for SphK1 and potent antitumor activity. Based on the crystal structure of SphK1, we transformed the structure of 2-epi-jaspine B and modified the hydrophobic side chain to obtain a series of 2-epi-jaspine B analogs. The MTT assay was used to examine the antitumor activities of these analogs. We identified a novel 2-epi-jaspine B analog YHR17, which has potent antiproliferative activities for tested cell lines with IC50 values that ranged from 0.68 to 5.68 µM and inhibited the proliferation of the A375 cell line by affecting the cell cycle and apoptosis. Furthermore, YHR17 inhibited SphK1 with more than 125-fold selectivity over SphK2.

15.
Kaohsiung J Med Sci ; 2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31736242

RESUMO

Accumulation of oxidative proteins within mitochondria leads to loss of mitochondrial function, which may lead to age-related degenerative diseases. Mitochondrial antioxidant defense capacity reflects the expression of mitochondrial unfolded protein response (mtUPR)-related proteins. Senescent cells are considered to be less resistant to cellular stress stimuli than exponentially growing cells. In this study, we aimed to investigate the ability of mitochondrial stress response in senescent cells to cope with the accumulation of mitochondrial unfolded proteins induced by hydrogen peroxide (H2 O2 ) and to understand the relevant molecular mechanisms. We report here that senescence-associated ß-galactosidase (SA-ß-gal) and senescence marker protein-30 (SMP-30), commonly used replicative senescence biomarkers, changed remarkably between population doubling (PD) 25 (exponentially growing cells) and PD50 (senescent cells) of MRC-5 fibroblasts. Mitochondrial unfolded proteins were significantly accumulated in H2 O2 -treated senescent cells, whereas mtUPR-related molecular chaperones (heat shock protein Hsp60 and Hsp10) and proteases (caseinolytic Clp protease) were not concomitantly elevated in senescent cells. In addition, decreased expression of stromal interacting molecule 1-Orai1-mediated store-operated Ca2+ entry following an declined intracellular calcium level after 2 mM calcium treatment together with H2 O2 addition, implying impairment of calcium influx in senescent MRC-5 during H2 O2 -induced injury. These findings suggest that senescent fibroblasts expressed higher vulnerability to H2 O2 -induced injury involving the imbalance of calcium homeostasis and impaired mitochondrial nuclear communication. This may provide useful information for the future development of therapeutic agents to prevent the adverse effects of aging on cells and the potential for treatment of proteinopathies in the elderly.

16.
Sci Rep ; 9(1): 17384, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31757985

RESUMO

Petaloid cytoplasmic male sterility (CMS) is a maternally inherited loss of male fertility due to the complete conversion of stamens into petal-like organs, and CMS lines have been widely utilized in carrot breeding. Petaloid CMS is an ideal model not only for studying the mitochondrial-nuclear interaction but also for discovering genes that are essential for floral organ development. To investigate the comprehensive mechanism of CMS and homeotic organ alternation during carrot flower development, we conducted transcriptome analysis between the petaloid CMS line (P2S) and its maintainer line (P2M) at four flower developmental stages (T1-T4). A total of 2838 genes were found to be differentially expressed, among which 1495 genes were significantly downregulated and 1343 genes were significantly upregulated in the CMS line. Functional analysis showed that most of the differentially expressed genes (DEGs) were involved in protein processing in the endoplasmic reticulum, plant hormone signal transduction, and biosynthesis. A total of 16 MADS-box genes were grouped into class A, B, C, and E, but not class D, genes. Several key genes associated with oxidative phosphorylation showed continuously low expression from stage T2 in P2S, and the expression of DcPI and DcAG-like genes also greatly decreased at stage T2 in P2S. This indicated that energy deficiency might inhibit the expression of B- and C-class MADS-box genes resulting in the conversion of stamens into petals. Stamen petaloidy may act as an intrinsic stress, upregulating the expression of heat shock protein (HSP) genes and MADS-box genes at stages T3 and T4 in P2S, which results in some fertile revertants. This study will provide a better understanding of carrot petaloid CMS and floral development as a basis for further research.

17.
Physiol Behav ; 213: 112689, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669775

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease, mainly characterized by cognitive dysfunction and memory impairment. Due to its pathological similarities to type 2 diabetes mellitus (T2DM), such as ß-amyloid deposition, oxidative stress, inflammation, disordered glucose metabolism, impaired signaling pathways of insulin and insulin-like growth factor-1 (IGF-1), we speculate that AD is another form of brain diabetes. Clarifying the relationship between T2DM and AD is important for us to better understand the exact pathological mechanisms of AD. Silibinin, a polyphenolic flavonoid extracted from the seeds of Silybum marianum, exerts hepatoprotective, anti- diabetic and neuroprotective effects. Streptozotocin (STZ), which is used to disrupt the insulin signal transduction pathway, could well mimic the sporadic AD models by intracerebroventricular (ICV) injection. Therefore, we selected ICV injection of STZ (ICV-STZ) to investigate the neuroprotective effects of silibinin in rats and to make a foundation for further exploring the relationship between AD and T2DM. ICV-STZ obviously caused memory damage, sharply reduced the number of nissl bodies and destroyed morphological structure of hippocampal neuronal cells, while silibinin attenuated the damages. Moreover, silibinin significantly decreased STZ-induced tau hyperphosphorylation (ser404) in hippocampus and cerebral cortex, markedly inhibited apoptosis of neurons induced by STZ, and up-regulated insulin signal transduction pathway. Silibinin exerts neuroprotective effect in STZ-treated rats, indicating the potential of silibinin for the treatment of AD patients with T2DM in future.

18.
Biochem Pharmacol ; 171: 113684, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678492

RESUMO

Recent discoveries revealed several types of programmed necrosis, such as necroptosis, ferroptosis, pyroptosis, etc. Necroptosis is mediated by signaling complexes with receptor-interacting protein kinases (RIPs) and mixed lineage kinase domain-like protein (MLKL). Here, we described an MLKL mediated non-canonical necroptosis through reactive oxygen species (ROS) in lung cancer cells triggered by a natural compound, tanshinol A (TSA). Morphologically, TSA-induced necrotic cell death is characterized by increased cell volume, transparent of cytoplasm, and rupture of the cell membrane. Biochemically, it induces intracellular ATP depletion and PI penetration. Molecularly, TSA-induced cell death is mediated by MLKL but independent of RIP1 and RIP3. Furthermore, TSA induces MLKL phosphorylation and membrane translocation, and cytosolic calcium accumulation. However, calcium shows no effect on TSA-induced cell death. Especially, TSA induces intracellular ROS generation, which was found to be the upstream of MLKL. Collectively, our data indicated that TSA triggers a novel type of programmed necrosis mediated by MLKL in lung cancer cells, which might have therapeutic potentials for lung cancer treatment.

19.
Mol Cell Endocrinol ; 500: 110641, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31711985

RESUMO

Endothelial cells (ECs) primarily rely on glycolysis for their energy metabolism, and the final product of glycolysis-lactate-is transferred out of cells via monocarboxylate transporter 4 (MCT4). We previously showed that MCT4 downregulation is involved in diabetic endothelial injury. However, the underlying regulatory mechanisms of MCT4 in diabetes remain unclear. This study showed that miR-425-5p was significantly upregulated in diabetic patients and human umbilical vein endothelial cells (HUVECs) treated with high glucose (HG) and interleukin-1ß (IL-1ß). MCT4 was shown to be a direct target gene of miR-425-5p, and miR-425-5p expression led to MCT4 downregulation, lactate accumulation and increased apoptosis in HUVECs. Furthermore, the results indicated that NF-κB signaling activation increased miR-425-5p levels and induced MCT4 downregulation, lactate accumulation and apoptosis in HUVECs. In conclusion, NF-κB/miR-425-5p/MCT4 axis activation plays a crucial role in the EC injury induced by HG and IL-1ß.

20.
Anal Chem ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31744292

RESUMO

In this work, in-situ growth of titanium dioxide micro-plug (TDMP) having mesoporous channels at the tip of glass micropi-pette induced by space-confined evaporation is reported. Moreover, clear ion current rectification (ICR) of single-material nanopore in saturated potassium chloride solution is observed for the first time. The TDMP presents an asymmetrical chan-nel structure with the top and bottom apertures of 12.3 ± 6.1 nm and 42.6 ± 19.7 nm, respectively. The TDMP exhibits out-standing ICR capability as the ions get transported through it due to the applied potential. The values for rectification coef-ficient (r = log2|I+1V/I-1V|) in saturated KCl solution under acidic (pH of 3.0) and alkaline (pH of 10.0) environments are 1.32 and -0.84, respectively. The intensity and direction of ICR can be adjusted by pH, or through the modification of citric acid. Meanwhile, the length and ion transport behavior of TDMP under different growth conditions (time and diameter) were also investigated. The TDMP with asymmetric mesoporous channels, maintaining ICR in saturated salt solution is expected to expand the application of nanopores in high-salt environment. Furthermore, growth of mesoporous material in the micropi-pette facilitates the miniaturization of the nanopore device, which further promotes its application potential.

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