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1.
J Nanosci Nanotechnol ; 20(2): 828-839, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383078

RESUMO

At present, high-performance cement-based composites are widely used, and they are prone to early cracking due to their high autogenous shrinkage stress. In this research, the uniformly dispersed GNPs were added into high-performance cementitious materials. The autogenous shrinkage of high-performance cementitious matrix materials with different incorporation of GNPs was also researched with water to cement ratio of 0.25, 0.30 and 0.35. According to hydration heat, hydration products, microstructure and porosity of GNPs cementitious matrix materials, the microcosmic mechanism for autogenous shrinkage was also investigated. It was testified that moderate addition of GNPs decreased the autogenous shrinkage of cement-based composites. Moreover, the autogenous shrinkage value was minimal after treatment with 0.10 wt% GNPs cement paste sample for 7 days, at the water to cement ratio of 0.35, and the depressed percentage of autogenous shrinkage reached 81.60% compared with the blank sample.

2.
Magn Reson Med ; 83(1): 94-108, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31400028

RESUMO

PURPOSE: To propose a highly accelerated, high-resolution dynamic contrast-enhanced MRI (DCE-MRI) technique called GRASP-Pro (golden-angle radial sparse parallel imaging with imProved performance) through a joint sparsity and self-calibrating subspace constraint with automated selection of contrast phases. METHODS: GRASP-Pro reconstruction enforces a combination of an explicit low-rank subspace-constraint and a temporal sparsity constraint. The temporal basis used to construct the subspace is learned from an intermediate reconstruction step using the low-resolution portion of radial k-space, which eliminates the need for generating the basis using auxiliary data or a physical signal model. A convolutional neural network was trained to generate the contrast enhancement curve in the artery, from which clinically relevant contrast phases are automatically selected for evaluation. The performance of GRASP-Pro was demonstrated for high spatiotemporal resolution DCE-MRI of the prostate and was compared against standard GRASP in terms of overall image quality, image sharpness, and residual streaks and/or noise level. RESULTS: Compared to GRASP, GRASP-Pro reconstructed dynamic images with enhanced sharpness, less residual streaks and/or noise, and finer delineation of the prostate without prolonging reconstruction time. The image quality improvement reached statistical significance (P < 0.05) in all the assessment categories. The neural network successfully generated contrast enhancement curves in the artery, and corresponding peak enhancement indexes correlated well with that from the manual selection. CONCLUSION: GRASP-Pro is a promising method for rapid and continuous DCE-MRI. It enables superior reconstruction performance over standard GRASP and allows reliable generation of artery enhancement curve to guide the selection of desired contrast phases for improving the efficiency of GRASP MRI workflow.

3.
J Phys Condens Matter ; 32(1): 015301, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31470427

RESUMO

2D nanomaterials with atomic thickness usually exhibit high specific surface areas and atom exposure rates, which are suitable for surface reaction related applications. In this study, we selected the oxalate ions as the structure-inducing agent to synthesize δ-MnO2 ultrathin nanosheets (~4.5 nm) via a facile hydrothermal method. Subsequently, an efficient exfoliation method to prepare single-layer MnO2 nanosheets (~0.9 nm) with the major exposed {0 0 1} facets was successfully developed. We found that the oxalate ions play a major role in the growth and formation of δ-MnO2 ultrathin nanosheets, and the formation process of the ultrathin structure was also investigated. The resulting single-layer MnO2 nanosheets (monosheets) with exposed {0 0 1} facets showed much higher catalytic performance for carcinogenic airborne formaldehyde, better than few-layer ultrathin nanosheets and nanoflowers with exposed {1 0 0} facets. The reasons for the high catalytic activity of MnO2 monosheets can be attributed to its higher surface areas and oxygen vacancy concentration. Moreover, the density-functional-theory (DFT) theoretical calculations showed that the oxygen vacancy in single-layer {0 0 1} facets exhibited the strongest adsorption/activation ability to O2 and H2O, which was very favorable for catalytic oxidation of formaldehyde. The synthesis strategy of ultrathin nanosheets described in this article may serve as reference and guidance for the preparation of other 2D ultrathin nanomaterials.

4.
Food Microbiol ; 86: 103344, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703877

RESUMO

This study aimed to evaluate the inhibitory activity of phenyllactic acid (PLA) against the biofilm formation of Enterococcus faecalis and to explore its potential molecular mechanism. The MIC value of PLA that inhibited the growth of E. faecalis R612-Z1 in BHI broth was 5 mg/mL. PLAs at subinhibitory concentrations of 1.25 and 2.50 mg/mL were found to inhibit biofilm formation by a crystal violet staining assay. The cell swimming and swarming motilities of E. faecalis were reduced in the presence of PLA. An apparent decrease in the thickness of PLA-treated biofilms was observed through confocal laser scanning microscopy analysis. The exopolysaccharide production in E. faecalis biofilms was inhibited by EPS quantification assay and scanning electron microscopy (SEM). qRT-PCR analyses showed that PLA down-regulated the transcription of Ebp pili genes (ebpABC) and Epa polysaccharide genes (epaABE). PLA inhibited the biofilm formation by interfering with cell mobility and EPS production of E. faecalis. In addition, PLA at concentrations of 10.0 mg/mL can effectively control the bacterial cells in a three-day-old mature biofilm of E. faecalis grown on 24-well flat-bottom polystyrene plates and stainless-steel surfaces. Thus, PLA is potentially an effective agent to control E. faecalis biofilms.

5.
Gen Comp Endocrinol ; 285: 113248, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31430448

RESUMO

Neuroparsin (NP) is an important neuropeptide in invertebrates. It is well-known that NP displays multiple biological activities, including antidiuretic and inhibition of vitellogenesis in insects. However, the information about its effect in crustaceans is scarce. In this study, the sequence of Sp-NP1 was selected from the transcriptome database from the mud crab, Scylla paramamosain. Sequence analyses indicate that the Sp-NP1 amino acid (AA) sequences consist of a 27 AA signal peptide and a 74 AA mature peptide, which contains 12 cysteine residues. qRT-PCR analysis has revealed that the expressions of Sp-NP1 gene are high in the nervous tissues and extremely low in the ovary and hepatopancreas. In situ hybridization has shown that the positive signals are localized in cell cluster 6 of protocerebrum and cell clusters 10 and 11 of deutocerebrum. The presence of Sp-NP1 in the haemolymph has been detected in S. paramamosain through western blot, which indicates that Sp-NP1 serves as an endocrine factor in the regulation of physiological activities. In vitro experiments have further shown that the mRNA level of vitellogenin in the hepatopancreas notably decreases following administration of recombinant Sp-NP1, while the mRNA level of vitellogenin receptor and cyclin B in the ovary shows no significant differences. Collectively, Sp-NP1 possibly can inhibit the production of vitellogenin in the hepatopancreas and has no direct effect on the ovary in S. paramamosain.

6.
J Mech Behav Biomed Mater ; 101: 103414, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31539736

RESUMO

The purpose of this study was to prepare anti-bacterial experimental resin composites with synthesized branched silicone methacrylate (BSM), and evaluate the influence of BSM on the physiochemical properties of the experimental resin composites. BSM was synthesized through a reaction between branched amino silicone and isocyanatoethyl methacrylate, and it was incorporated into 2,2-bis [4- (2-hydroxy-3-methacryloxy-propoxy)phenyl] propane (Bis-GMA)/triethyleneglycol dimethacrylate (TEGDMA) (50 wt/50 wt) with a series of concentrations to form resin matrices. The experimental composites (EC) were then prepared by mixing different resin matrices with silaned BaAlSiO2 fillers. The double bond conversion, volumetric shrinkage, and mechanical properties of the prepared experimental resin composites were measured among groups with different BSM concentrations. A bacterial adhesion assay for bacteria colony counting was conducted using Streptococcus mutans. The results showed that all of the experimental resin composites had nearly the same double bond conversion ranging from 60.9 ±â€¯0.3% to 62.4 ±â€¯1.3% (p > 0.05). BSM could reduce the volumetric shrinkage of experimental resin composites, and composites with 20 wt% and 30 wt% of BSM in the resin matrix had the lowest volumetric shrinkage (p < 0.05). The flexural strength would be impaired after adding 30 wt% of BSM into the resin matrix of experimental resin composites, and BSM had no negative influence on the flexural modulus in this study. The water contact angles on the surfaces of BSM-containing composites were all higher than that on the surface of control group (p < 0.05), and followed a trend of increasing with the increase of the BSM concentration. S. mutans adherence on the surfaces of the EC-10%, EC-15%, EC-20% and EC-30% groups were significantly lower compared with the control group. This work suggested that the hydrophobic resin composites incorporating of BSM could reduce S. mutans adhesion and possibly increase the longevity of resin composite restorations.

7.
Ultrasound Med Biol ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31784201

RESUMO

Atrial fibrillation (AF) poses challenges in use of the echocardiogram to assess left ventricular (LV) function. The index beat method has been found to agree well with the average method. We aimed to assess the value of the index beat method in evaluation of LV function using the dual pulsed wave Doppler technique. Peak early diastolic mitral inflow velocity (E) and diastolic (e') and systolic (s') mitral annulus velocity were simultaneously obtained and measured beat-to-beat in patients with AF. The index beat s' exhibited the best correlation (r = 0.96 and 0.92, respectively, for septal and lateral wall, both p values = 0.000) with the mean, while E/e' at the pre-index beat, rather than at the index beat-initiated cycle, had the best correlation with the mean (r = 0.88 for septal and 0.97 for lateral wall, both p values = 0.000).

9.
Stem Cell Res Ther ; 10(1): 363, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791397

RESUMO

BACKGROUND: Diabetic nephropathy (DN) is one of the most severe chronic diabetic complications and the main cause of end-stage renal disease. Chronic inflammation plays a key role in the development of DN. However, few treatment strategies are available; therefore, new and effective strategies to ameliorate DN at the early stage must be identified. METHODS: Mesenchymal stem cells (MSCs) are characterized by anti-inflammatory and immune regulatory abilities. We developed a rhesus macaque model of DN and administered MSCs four times over 2 months. We measured blood glucose level, HbA1c, and levels of renal function parameters in the blood and urine, and cytokine levels in the kidney and blood circulatory system of rhesus macaques. Also, we analyzed the renal pathological changes of rhesus macaques. In vitro, we treated tubular epithelial cells (HK2) with 30 mmol/L glucose and 10 ng/mL human recombinant TNF-alpha (rhTNF-α) and explored the effects of MSCs on inflammation and Na+-glucose cotransporter 2 (SGLT2) expression in HK2. RESULTS: We found that MSCs decreased the blood glucose level and daily insulin requirement of DN rhesus macaques. Furthermore, MSCs had a dominant function in improving renal function and decreasing SGLT2 expression on renal tubular epithelial cells. Also, renal pathological changes were ameliorated after MSC treatment. Moreover, MSCs powerfully reduced inflammation, especially decreased the level of pro-inflammatory cytokine interleukin-16 (IL-16), in the kidney and blood circulatory system. CONCLUSIONS: Our study is an important step to explore the mechanism of MSCs in ameliorating the early stage of DN, potentially through influencing SGLT2 expression and resulting in improved glycemic control and anti-inflammation. We hope these findings would provide insights for the clinical application of MSCs in DN.

10.
EBioMedicine ; 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31791845

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) have drawn increasing attention because they play a pivotal role in various types of autoimmune diseases, including rheumatoid arthritis (RA). Fibroblast-like synoviocytes (FLSs), a prominent component of hyperplastic synovial pannus tissue, are the primary effector cells in RA synovial hyperplasia and invasion which can lead to joint destruction. In this study, we investigated whether lncRNAs could act as competing endogenous RNAs to regulate the pathological behaviors of RA-FLSs. METHODS: LncRNA microarray was conducted to establish lncRNA expression profiles in FLSs isolated from RA patients and healthy controls (HCs). Differentially expressed lncRNAs were verified by quantitative real-time PCR (qRT-PCR) on RA-FLSs and synovial fluid. The functional role of lncRNA PICSAR downregulation was evaluated in RA-FLSs. We conducted molecular biological analysis to predict miRNAs which have a potential binding site for PICSAR and further refined the results by qRT-PCR. Luciferase reporter assay was adopted to validate the interaction of lncRNA PICSAR and miR-4701-5p. Western Blot and qPCR were used to identify the target gene and protein. The functional role of miR-4701-5p upregulation was examined in RA-FLSs. FINDINGS: We identified a long intergenic non-protein-coding RNA162 (LINC00162), also known as lncRNA PICSAR (p38 inhibited cutaneous squamous cell carcinoma associated lincRNA), has significantly higher expression in RA-FLSs and RA synovial fluid. The cell proliferation, migration, invasion and proinflammatory cytokines production of RA-FLSs showed significant alterations after the lncRNA PICSAR suppression. Mechanistically, lncRNA PICSAR functioned through sponging miR-4701-5p in RA-FLSs. INTERPRETATION: Our results reveal PICSAR may exert an essential role in promoting synovial invasion and joint destruction by sponging miR-4701-5p in RA and that lncRNA PICSAR may act as a biomarker of RA.

11.
Acc Chem Res ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31789016

RESUMO

The concept of pericyclic reactions and the explanation of their specificity through orbital symmetries introduced a new way of understanding reactions and looking for new ones. One of the 1965 Woodward-Hoffmann communications described "the (as yet unobserved) symmetry-allowed 6 + 4 combination", the prediction of a new field of "higher-order" cycloadditions, involving more than six electrons. Later these authors predicted exo-stereoselectivity for the [6 + 4]-cycloaddition. Chemists rushed to test this prediction (for the most part successfully). For more than half a century, chemists have hunted for additional higher-order cycloadditions. The application of catalysis within organic chemistry allows the accomplishment of previously unattainable reactions, including higher-order cycloadditions. The many examples of [8 + 2], [6 + 4], and cycloadditions of even higher electron-counts discovered since the Woodward-Hoffmann rules were introduced illustrate the difficulty in predicting which of these transformations will occur when two highly unsaturated molecules react. Periselectivity has been a challenge, and the development of enantioselective variants has been elusive. While progress was made, the rise of organocatalysis in asymmetric synthesis has led to a surge of interest in stereoselective versions of higher-order cycloadditions. Through organocatalytic activation of conjugated cyclic polyenes and heteroaromatic compounds, asymmetric [8 + 2]-, [6 + 4]-, and [10 + 4]-cycloadditions have been realized by our groups. In this century, [6 + 4]-cycloadditions have been found also to occur in enzyme-catalyzed reactions for the biosynthesis of spinosyn A, heronamide, and streptoseomycin natural products. A whole new class of enzymes, the pericyclases that catalyze pericyclic reactions, has been discovered. A remarkable aspect of these recent developments is the cross-disciplinary research involved: from organic synthesis to computational studies integrated with experimental studies of reaction mechanisms, intermediates, and dynamics, to understanding mechanisms of enzyme catalysis and engineering of enzymes. This Account describes how our groups have been involved in the expansion of the higher-order cycloaddition frontiers. We describe both the history and recent progress in higher-order cycloadditions, and how these advances have been made by our collaborative experimental and computational studies. Progress in asymmetric organocatalysis, incorporating enantioselective higher-order cycloadditions in organic synthesis, and the stereoselective synthesis of important scaffolds will be highlighted. Experimental progress and computational modeling with density functional theory (DFT) has identified ambimodal cycloaddition pathways and led to the realization that multiple products of pericyclic reactions are linked by common transition states. Molecular dynamic simulations have provided fundamental understanding of factors controlling periselectivity and have led to discoveries of a group of enzymes, the pericyclases, which catalyze pericyclic reactions such as [6 + 4]-cycloadditions.

12.
Aging (Albany NY) ; 112019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31794427

RESUMO

Ninjurin2 (Ninj2) is an adhesion protein expressed in neurons and glial cells. The current study tested its expression and potential functions in human glioma. We show that Ninj2 mRNA and protein levels are significantly upregulated in human glioma cells and tissues. In established and primary human glioma cells, Ninj2 shRNA or knockout (by CRISPR/Cas9 gene editing) potently inhibited cell survival, growth, proliferation, cell migration and invasion, while inducing apoptosis activation. Contrarily, ectopic overexpression of Ninj2 promoted glioma cell progression in vitro. In human glioma tissues and cells, Ninj2 co-immunoprecipitated with multiple receptor tyrosine kinases (EGFR, PDGFRß and FGFR), required for downstream Akt and Erk activation. Akt and Erk activation was potently inhibited by Ninj2 shRNA or knockout, but enhanced with ectopic Ninj2 overexpression in glioma cells. In summary, we show that Ninj2 overexpression promotes glioma cell growth.

13.
Water Sci Technol ; 80(6): 1134-1144, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31799957

RESUMO

A two-phase anaerobic system comprised of upflow anaerobic sludge bed (UASB) reactor for hydrogen production and internal circulation reactor (IC) for methane production was proposed and investigated at laboratory scale and mesophilic temperature (35 °C). Hydrogen was efficiently produced from the UASB with the highest production rate of 3.00 ± 0.04 L · L-1 reactor · d-1 at optimum hydraulic retention time (HRT) of 6 h and in the IC, methane was also produced from residual organic matter and soluble metabolite products (SMP) with a production rate of 2.54 ± 0.04 L · L-1 reactor · d-1 at optimum HRT of 15 h. Finally, system HRT of 21 h was determined to be the optimum HRT at which energy conversion efficiency increased from 9.6 ± 0.1% (hydrogen only production) to 72.4 ± 2.5% (hydrogen and methane coproduction) and system chemical oxygen demand (COD) removal reached up to the high level of 90.1 ± 2.1%.

14.
Hu Li Za Zhi ; 66(6): 90-97, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31802459

RESUMO

This report discusses an experience of taking care of a breast cancer patient with rapidly deteriorating, fungating wounds and herpes simplex virus wounds and describes the physical and psychological effects on the patient and the related decreases in the quality of life of both the patient and her caregivers. Nursing care was implemented from December 14th, 2017 to January 23rd, 2018. Data collection was performed through direct caregiving, observation, interviews, and chart review. Three major problems were identified: difficulties with wound care, psychological distress of the patient, and the coping problems of the caregivers. Based on these problems, nursing interventions were implemented. During the period, fungating wound care guidelines were used to teach the patient and her caregivers the core principles of fungating wound management. Meanwhile, the COPE framework (creativity, optimism, planning, and expert information) was applied to train the patient and her caregivers how to develop problem-solving skills and build self-confidence. Finally, the patient and her family successfully overcame these challenges. The patient was relieved of stress and anxiety, became better able to self-manage her symptoms, sustain hope for the future, and improve her perception of body self-image. We suggested that the patient and her family be considered a single, supportive unit and then helped them cope with the disease and build self-care confidence in order to improve their life quality and to coexist with the disease. We hope that our clinical experience will be taken as a reference by patient caregivers.

15.
BMC Pulm Med ; 19(1): 196, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31684936

RESUMO

BACKGROUND: Epidemiologic studies have shown inconsistent conclusions about the effect of ulinastain treatment for acute respiratory distress syndrome (ARDS). It is necessary to perform a meta-analysis of ulinastatin's randomized controlled trials (RCTS) to evaluate its efficacy for treating ARDS. METHODS: We searched the published RCTs of ulinastatin treatment for ARDS from nine databases (the latest search on April 30th, 2017). Two authors independently screened citations and extracted data. The meta-analysis was performed using Rev. Man 5.3 software. RESULTS: A total of 33 RCTs involving 2344 patients satisfied the selection criteria and were included in meta-analysis. The meta-analysis showed that, compared to conventional therapy, ulinastatin has a significant benefit for ARDS patients by reducing mortality (RR = 0.51, 95% CI:0.43~0.61) and ventilator associated pneumonia rate (RR = 0.50, 95% CI: 0.36~0.69), and shortening duration of mechanical ventilation (SMD = -1.29, 95% CI: -1.76~-0.83), length of intensive care unit stay (SMD = -1.38, 95% CI: -1.95~-0.80), and hospital stay (SMD = -1.70, 95% CI:-2.63~-0.77). Meanwhile, ulinastatin significantly increased the patients' oxygenation index (SMD = 2.04, 95% CI: 1.62~2.46) and decreased respiratory rate (SMD = -1.08, 95% CI: -1.29~-0.88) and serum inflammatory factors (tumor necrosis factor-α: SMD = -3.06, 95% CI:-4.34~-1.78; interleukin-1ß: SMD = -3.49, 95% CI: -4.64~-2.34; interleukin-6: SMD = -2.39, 95% CI: -3.34~-1.45; interleukin-8: SMD = -2.43, 95% CI: -3.86~-1.00). CONCLUSIONS: Ulinastatin seemly showed a beneficial effect for ARDS patients treatment and larger sample sized RCTs are needed to confirm our findings.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31699366

RESUMO

The abnormally high activity of the proteasome system is closely related to the occurrence and development of various tumors. PSMB4 is a non-catalytic subunit for the proteasome assembly. Although the reports from genetic screening have demonstrated it's a driver gene for cell growth in several types of solid tumor, its expression pattern and regulatory mechanisms in malignant diseases are still elusive. Here, we found that PSMB4 is overexpressed in cervical cancer tissues. And knockdown of PSMB4 significantly inhibited cervical cancer cell proliferation. The mechanistic study revealed that FoxM1, a master regulator of cell division, binds directly to the promoter region of PSMB4 and regulates the PSMB4 expression in the mRNA level. In addition, the data analysis from TCGA showed a positive correlation between FxoM1 and PSMB4 in cervical cancer. Furthermore, the loss of functional and rescue experiments confirmed that PSMB4 is required for FoxM1-driven cervical cancer cell proliferation. Collectively, our study explains the phenomenon of dysregulated expression of PSMB4 in cervical cancer tissues and verifies its driver effect on cancer cell proliferation. More importantly, it highlights a FoxM1-PSMB4 axis could be a potential target for the treatment of cervical cancer.

17.
Cell Biochem Funct ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31702057

RESUMO

It is well known that the sine oculis homeobox 4 (SIX4) expression is very relevant to the progression of multiple cancers. Moreover, we found that miR-802 could directly target the SIX4. However, the precise mechanism of miR-802 in glioblastoma multiforme (GBM) is still unknown. The aim of this study is to investigate the roles of miR-802/SIX4 axis in GBM. Here, our results showed that the SIX4 expression was obviously increased in GBM tissues and cell lines, and the miR-802 level was distinctly decreased. What is more, the SIX4 expression was negatively related to the miR-802 level in GBM tissues. Furthermore, increased miR-802 level evidently restrained the proliferation, invasion, and epithelial-mesenchymal transition (EMT) of GBM cells. Next, we confirmed that miR-802 could directly target SIX4 by using luciferase reporter assay. Besides, the knockdown of SIX4 had the similar effects with miR-802 overexpression on GBM cells. The inhibitory effects of miR-802 mimic were partially blocked by SIX4 overexpression. Altogether, the overexpression of miR-802 restrained cell proliferation, invasion, and EMT of GBM cells via the regulation of SIX4. SIGNIFICANCE OF THE STUDY: An elevated expression of SIX4 has been observed in colorectal cancer and nonsmall cell lung cancer. However, the precise roles of SIX4 in GBM have not been elucidated. Our study for the first time demonstrated that SIX4 level was significantly upregulated in GBM. Additionally, the knockdown of SIX4 inhibited cell growth, invasion, and the EMT of GBM. Moreover, our data suggested a significant negative correlation between miR-802 and SIX4 expression in GBM. MiR-802 suppressed GBM cell proliferation, invasion, and EMT by directly targeting SIX4, which suggested important roles for miR-802/SIX4 axis in the GBM pathogenesis and its potential application in cancer therapy.

18.
Genomics ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31733270

RESUMO

In this investigation, whole-genome identification and functional characterization of the cotton dehydrin genes was carried out. A total of 16, 7, and 7 dehydrin proteins were identified in G. hirsutum, G. arboreum and G. raimondii, respectively. Through RNA sequence data and RT-qPCR validation, Gh_A05G1554 (GhDHN_03) and Gh_D05G1729 (GhDHN_04) were highly upregulated, and knockdown of the two genes, significantly reduced the ability of the plants to tolerate the effects of osmotic and salt stress. The VIGS-plants recorded significantly higher concentration levels of oxidants, hydrogen peroxide (H2O2) and malondialdehyde (MDA), furthermore, the four stress responsive genes GhLEA2, Gh_D12G2017 (CDKF4), Gh_A07G0747 (GPCR) and a transcription factor, trihelix, Gh_A05G2067, were significantly downregulated in VIGS-plants, but upregulated in wild types under osmotic and salt stress condition. The result indicated that dehydrin proteins are vital for plants and can be exploited in developing a more osmotic and salt stress-resilient germplasm to boost and improve cotton production.

19.
Oncol Rep ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31746437

RESUMO

The aim of the present study was to investigate the synergistic antitumor effects of emodin and 3'­azido­3'­deoxythymidine (AZT) on human chronic myeloid leukemia cells and to explore the possible underlying mechanisms. The K562 cells were treated with emodin and AZT, and the rates of cell inhibition and apoptosis were determined by MTT assay and flow cytometry, respectively. The mRNA expression of EGR1 was detected by reverse transcription­polymerase chain reaction (RT­PCR) analysis. The expression of EGR1 was silenced using siRNA, and then protein expression of ß­catenin was detected by western blotting. The results demonstrated that AZT enhanced the inhibitory effect of emodin in K562 cells. The IC50 of the emodin/AZT combination at 24, 48 or 72 h was 23.6/235.6, 10.2/101.6 or 5.9/58.5 µmol/l, respectively, which was significantly lower compared with the IC50 of emodin (all >32 µmol/l) or AZT (all >320 µmol/l) alone. There was a dose­dependent response to the combined emodin and AZT treatment, and the calculation of the combination index yielded values <1, demonstrating the synergistic effect of the combined treatment compared with the control (P<0.05). Furthermore, the combination of emodin and AZT increased apoptosis in K562 cells (P<0.05). Apoptosis was higher in the combination group compared with that of either treatment alone or control groups. The expression of early growth response­1 (EGR1) in K562 cells was upregulated in a time­dependent manner. The expression of EGR1 was higher in the combination group compared with that in the emodin or AZT alone groups. The expression of the Wnt/ß­catenin signaling pathway in the combination group was lower compared with that in the emodin or AZT alone groups. The expression of the Wnt/ß­catenin signaling pathway was significantly increased following EGR1 siRNA transfection. These data suggest that treating K562 cells with a combination of emodin and AZT exhibits reduced toxicity and improves therapeutic efficacy, and that the growth, inhibition, apoptosis and regulation of the Wnt/ß­catenin signaling pathway in human chronic myeloid leukemia cells by emodin and AZT may be associated with the expression of EGR1.

20.
Colloids Surf B Biointerfaces ; 185: 110618, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31706145

RESUMO

Alkaline phosphatase (ALP) is an important biomarker for diagnosis, and the abnormal level of serum ALP is closely related to a variety of diseases. In present work, a ratiometric fluorescence probe based on hybrid nanoparticles CDs@YVO4: Dy3+ nanoparticle is introduced for alkaline phosphatase (ALP) activity determination. The CDs@YVO4: Dy3+ probe is constructed by the carbon dots (CDs) and YVO4: Dy3+ through a simple mixing method, in which the blue emission of CDs at 405 nm acts as the calibrated signal, the green emission of YVO4: Dy3+ at 574 nm decreased with the increasing targets ALP, and used as the output signal. In addition, the Cu2+ and pyrophosphate (PPi) were also employed in this strategy to utilize the excellent fluorescnece quenching efficiency of Cu2+ to the Dy3+ ions emission of CDs@YVO4: Dy3+, as well as the strong affinity of PPi for Cu2+. In the presence of analyts ALP, ALP catalyzes the hydrolysis of PPi, causing the release of Cu2+, resulting in the Dy3+ ions emission quenched, while the CDs emission at 405 nm retained unchanged, based on this, we designed the off-on-off ratiometric fluorescence platform for ALP sensing. The experiment result shows that the ratio of F574/F405 is linear to the concentration of ALP in arange of 0.05∼3000 U/L with a detection limit of 0.04 U/L, which is comparable or better than those reported fluorescence probe, especially the calibrated signal introduction of CDs can eliminate the background interference, improve the accuracy of proposed probe greatly. Furthermore, the discrimination of ALP enzyme inhibitor with the IC50 of 26 µM, and ALP concentration in real human serum sample has also demonstrated the applicability of CDs@YVO4: Dy3+ fluorescence sensor well.

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