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1.
Artigo em Inglês | MEDLINE | ID: mdl-31677796

RESUMO

The prognosis for hepatocellular carcinoma (HCC) is dismal. Long noncoding RNA PVT1 has been linked to malignancies and might be a deleterious therapy target. However, the key events controlling its expression in HCC remain undetermined. Here, we address how PVT1 is fine-regulated and its downstream signaling in hepatoma cells. Interestingly, we found that c-Myc and P53 could divergently regulate PVT1 transcription. Oncoprotein c-Myc enhances PVT1 expression, whereas P53 suppresses its expression. We also identified miR-214 as a crucial, negative regulator of PVT1. Consistently, high miR-214 levels were significantly correlated with diminished PVT1 expression in HCC specimens. Silencing of PVT1 by ectopic miR-214 or siRNAs markedly inhibited viability and invasion of HCC cells. In opposition, inhibition of endogenous miR-214 promoted PVT1 expression and enhanced cell proliferation. Notably, oncogenic GDF15 is a potential downstream target of the miR-214-PVT1 signaling. Collectively, our results show that the c-Myc/P53/miR-214-PVT1-GDF15 axis is implicated in HCC development, shedding light on the mechanistic actions of PVT1 and representing potential targets for HCC clinical intervention.

2.
J Colloid Interface Sci ; 560: 312-320, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31670226

RESUMO

In order to enhance the gas response of polypyrrole to NO2, the polypyrrole/Fe2O3 nanocomposites are synthesized by one-step hydrothermal route. The presence of ferric oxide in composites is demonstrated by XPS, HRTEM and TG analyses. The polypyrrole/Fe2O3 sensor exhibits high selectivity and response to NO2 at 50 °C. Compared with other polypyrrole/metal oxide materials, the polypyrrole/Fe2O3 materials are easy to be synthesized, and the gas sensor has a higher response of 220.7%, lower detection limit of 0.1 ppm and good linear relationship when the NO2 concentrations range from 0.1 ppm to 10 ppm. The gas response is greatly improved in comparison with the pure polypyrrole and Fe2O3. The reason for the improved response is also discussed.

3.
Scand J Gastroenterol ; : 1-6, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31687871

RESUMO

Background: Brain metastasis (BM) from colorectal cancer (CRC) seriously affects the survival and quality of life of patients. However, this disease is not fully understood. It is not clear when follow-up monitoring should be conducted to achieve early diagnosis. Furthermore, the reported prognostic factors have varied among different studies. Our study aims to determine the clinicopathological, survival and prognostic factors, as well as the timing of BM occurrence.Methods: We retrospectively studied the patients with BM from CRC between January 2000 and July 2017. The clinicopathologic features were assessed, and the time from primary tumor surgery and extracranial metastases (lung, liver and bone) to the occurrence of BM was calculated, respectively. Survival time after BM was statistically analyzed. Multivariate Cox analysis was carried out to determine the independent factors that affected survival.Results: 52 patients were analyzed. Most of the patients (86.5%) had combined extracranial metastases when BM was diagnosed, and lung was the commonest extracranial metastasis location. The median time interval from CRC surgery to the diagnosis of BM was 20.5 months, and the median time interval from lung, liver and bone metastases to BM was 7, 5 and 2 months, respectively. After diagnosis of BM, the median survival was 9 months. Extracranial metastases (p =.012) and Karnofsky performance status (p =.025) were independent prognostic factors based on multivariate analysis.Conclusion: BM from colorectal cancer often occur in the late stage, and has an extremely poor prognosis. Identifying the timing of brain metastasis can help to detect this disease early.

4.
Diabetes Metab J ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31701685

RESUMO

BACKGROUND: Membrane CD36 is a fatty acid transporter implicated in the pathogenesis of metabolic disease. We aimed to evaluate the association between plasma CD36 levels and diabetes risk and to examine if the association was independent of adiposity among Danish population. METHODS: We conducted a case-cohort study nested within the Danish Diet, Cancer and Health study among participants free of cardiovascular disease, diabetes and cancer and with blood samples and anthropometric measurements (height, weight, waist circumference, and body fat percentage) at baseline (1993 to 1997). CD36 levels were measured in 647 incident diabetes cases that occurred before December 2011 and a total of 3,515 case-cohort participants (236 cases overlap). RESULTS: Higher plasma CD36 levels were associated with higher diabetes risk after adjusting for age, sex and other lifestyle factors. The hazard ratio (HR) comparing high versus low tertile of plasma CD36 levels was 1.36 (95% confidence interval [CI], 1.00 to 1.86). However, the association lost its significance after further adjustment for different adiposity indices such as body mass index (HR, 1.23; 95% CI, 0.87 to 1.73), waist circumference (HR, 1.21; 95% CI, 0.88 to 1.68) or body fat percentage (HR, 1.20; 95% CI, 0.86 to 1.66). Moreover, raised plasma CD36 levels were moderately associated with diabetes risk among lean participants, but the association was not present among overweight/obese individuals. CONCLUSION: Higher plasma CD36 levels were associated with higher diabetes risk, but the association was not independent of adiposity. In this Danish population, the association of CD36 with diabetes risk could be either mediated or confounded by adiposity.

6.
Curr Med Chem ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701843

RESUMO

Diabetic nephropathy (DN) is one of the most common and important microvascular complications of diabetes mellitus (DM). The main clinical features of DN are proteinuria and a progressive decline in renal function , which are associated with structural and functional changes in the kidney. The pathogenesis of DN is multifactorial, including genetic, metabolic and haemodynamic factors, which can trigger a sequence of events. Controlling metabolic risks such as hyperglycaemia, hypertension and dyslipidaemia is not enough to slow the progression of DN. Recent studies have emphasized immunoinflammation as a critical pathogenic factor in the progression of DN. Therefore, targeting inflammation is considered a potential and novel treatment strategy for DN. In this review, we will briefly introduce the inflammatory process of DN and discuss the anti-inflammatory effects of antidiabetic drugs when treating DN.

7.
Mar Genomics ; : 100719, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31680055

RESUMO

The Acinetobacter baumanni J1 isolated from surface water of the Eastern Pacific Ocean, demonstrated significant algicidal activity on the algae Alexandrium tamarense. Interestingly, this strain showed the ability to produce an acyl-homoserine lactone (AHL) quorum sensing molecule. To better understand its AHL producing mechanism and its ecological functions, the genome of A. baumanni strain J1 was completely sequenced. The genome contained a circular chromosome of 3,948,465 bp with an average GC content of 39.9 mol%. A total of 3707 protein coding genes, 41 tRNA genes and 16 rRNA genes were obtained. In silico genome annotation identified a LuxI putative gene located on contig 4. Subsequent thin-layer chromatography analysis indicated that C8-AHL could be produced by A. baumanni J1, which confirmed the authenticity of the LuxI gene. Taken together, this work describes an algicidal bacterium that is capable of producing an AHL molecule, which may represent a valuable tool for developing microbial methods to control harmful algae.

8.
Eur J Pharmacol ; : 172772, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31697934

RESUMO

Vascular calcification increased the risk of morbidity and mortality in patients with cardiovascular diseases, chronic kidney diseases, and diabetes. However, viable therapeutic methods to target vascular calcification are limited. Aloe-emodin (AE), an anthraquinone is a natural compound found in the leaves of Aloe-vera. In this study, we investigated the underlying mechanism of AE in the calcification of vascular smooth muscle cells (VSMCs) and murine thoracic aorta. We demonstrate that AE repressed not only the phenotypes of Ca2+ induced calcification but also level of calcium in VSMCs. AE has no effect on cell viability in VSMC cells. Alizarin red and von Kossa stainings and calcium quantification showed that Ca2+ induced vascular calcification is significantly decreased by AE in a concentration-dependent manner. In contrast, AE attenuated Ca2+ induced calcification through inhibiting osteoblast differentiation genes such as SMAD4, collagen 1α, osteopontin (OPN), Runt-related transcription factor (RUNX-2) and Osterix. AE also suppressed Ca2+ induced osteoblast-related protein expression including collagen 1α, bone morphogenic protein 2 (BMP-2), RUNX-2 and smooth muscle actin (SMA). Furthermore, Alizarin red, von Kossa stainings and calcium quantification showed that AE significantly inhibited the calcification of ex vivo ring formation in murine thoracic aorta, and markedly inhibited vitamin D3 induced medial aorta calcification in vivo. Taken together, our findings suggest that AE may have therapeutic potential for the prevention of vascular calcification program.

9.
Colloids Surf B Biointerfaces ; 185: 110606, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31698265

RESUMO

This study demonstrated a novel injectable-thermoreversible hydrogel scaffold composing of PLuronic F127, carboxymethyl hexanoyl chitosan (CA) and glyoxal (Gx) for encapsulating human osteosarcoma MG-63 cells. The hydrogel was prepared by simply mixing CA, F127 and Gx. In so doing, this system exhibited short gelation time and higher gelation temperature. In addition, this hydrogel exhibited thermo-reversibility, that is, the hydrogel can liquefy at room temperature and revert to gel state at body temperature. The encapsulated cells in this hydrogel proliferated more than 400% in the 5-day incubation. Based on these results, these F127/CA/Gx hydrogels can be used to encapsulate cells for tissue engineering applications.

10.
Math Biosci Eng ; 16(6): 6562-6586, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31698576

RESUMO

In the IoT environment, many terminal devices are deployed in unattended areas. If these devices are moved elsewhere by an attacker, the wrong environmental sensing values are obtained, which causes a major disaster. In this paper, we propose an ambient authentication mechanism based on audio to be used in multi-factor authentication by using the ambient sensors equipped with a smart phone. An ultrasonic signal that is not detectable by the human ear was transmitted by the authenti-cator, and the attenuated signal received by the user being authenticated was transmitted back to the authentication server. The transmitted and received decoded symbol sequences of the audio signal are used to calculated the bit error rate, which is used to measure the relative distance. Our proposed method can narrow the authentication distance to less than 0.5 meters, which can greatly improve the security of the authentication system.

11.
J Neuroinflammation ; 16(1): 206, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699098

RESUMO

BACKGROUND: Oligodendrocytes (OLs) death after spinal cord injury (SCI) contributes to demyelination, even leading to a permanent neurological deficit. Besides apoptosis, our previous study demonstrated that OLs underwent receptor-interacting serine-threonine kinase 3(RIP3)/mixed lineage kinase domain-like protein (MLKL)-mediated necroptosis. Considering that necroptosis is always accompanied with pro-inflammatory response and quercetin has long been used as anti-inflammatory agent, in the present study we investigated whether quercetin could inhibit necroptosis of OLs and suppress the M1 macrophages/microglia-mediated immune response after SCI as well as the possible mechanism. METHODS: In this study, we applied quercetin, an important flavonoid component of various herbs, to treat rats with SCI and rats injected with saline were employed as the control group. Locomotor functional recovery was evaluated using Basso-Beattie-Bresnahan (BBB) scoring and rump-height Index (RHI) assay. In vivo, the necroptosis, apoptosis, and regeneration of OLs were detected by immunohistochemistry, 5'-bromo-2'-deoxyuridine (BrdU) incorporation. The loss of myelin and axons after SCI were evaluated by Luxol fast blue (LFB) staining, immunohistochemistry, and electron microscopic study. The polarization of macrophages/microglia after SCI and the underlying mechanisms were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry. In vitro, the ATP and reactive oxygen species (ROS) level examination, propidium iodide (PI) labeling, and Western blotting were used to analyze the necroptosis of cultured OLs, while the signaling pathways-mediated polarization of cultured macrophages/microglia was detected by qRT-PCR and Western blotting. RESULTS: We demonstrated that quercetin treatment improved functional recovery in rats after SCI. We then found that quercetin significantly reduced necroptosis of OLs after SCI without influencing apoptosis and regeneration of OLs. Meanwhile, myelin loss and axon loss were also significantly reduced in quercetin-treated rats, as compared to SCI + saline control. Further, we revealed that quercetin could suppress macrophages/microglia polarized to M1 phenotype through inhibition of STAT1 and NF-κB pathway in vivo and in vitro, which contributes to the decreased necroptosis of OLs. CONCLUSIONS: Quercetin treatment alleviated necroptosis of OLs partially by inhibiting M1 macrophages/microglia polarization after SCI. Our findings suggest that necroptosis of OLs may be a potential therapeutic target for clinical SCI.

12.
Clin Nucl Med ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31693613

RESUMO

We report a large mobile bladder calculus with intense Tc-MDP uptake demonstrated on both whole-body bone scintigraphy and SPECT/CT images in a patient with complicated chronic history of urolithiasis and urinary tract infection. Bone tracer uptake in bladder calculus is a rare phenomenon and might be related to the composition and matrix of calculus, direct exposure to excreted radiotracer, and bacterial colonization on the surface of calculus.

13.
ACS Nano ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31702890

RESUMO

The intricate features of many-body interactions and spin-orbit coupling play a significant role in numerous physcial phenomena. Particularly in two-dimensional transition metal dichalcogenides (2D-TMDs), excitonic dynamics are a key phenomenon that promises opportunities for diverse range of device applications. Here, we report the direct observation of a visible-range three-dimensional resonant exciton and its associated charged exciton in monolayer tungsten diselenide, as compared to monolayer molybdenum disulfide. A comprehensive experimental study that includes high-resolution TEM, Raman, high-resolution spectroscopic ellipsometry over a wide temperature range down to 4K, high-energy temperature and excitation power-dependent photoluminescence spectroscopy has been conducted. It is supported by first-principles calculations to unravel the influence of spin-orbit coupling in the formation of the resonant exciton and to identify its in-plane and out-of-plane features. Furthermore, we study the impact of temperature and thickness on the spin-orbit coupling strength in 2D-TMDs. This work is crucial in creating a platform in the fundamental understanding of high-energy resonant exciton in layered two-dimensional systems, and that such high-energy optoelectronic features make them an increasingly attractive candidate for novel electronic and optoelectronic applications particularly in the aspects of solar cells and light-emitting diodes via the manipulation of excitonic states.

14.
Sensors (Basel) ; 19(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652797

RESUMO

In 2014, Yang proposed a method to enhance the current EMV credit card protocol (EPMAR). However, the protocol ignores the exceeding of a credit quota caused by multiple offline transactions, with the result that the amount spent can exceed the risk control scope. In this paper, we proposed an EMV-compatible offline mobile payment protocol with mutual authentication (EOPMA) to enhance EPMAR. In EOPMA, we use the reverse hash chain technique to guarantee the payment, which solves the problem of credit quotas getting exceeded because of multiple offline payments. During a transaction, in addition to payment for merchandise, an offline authorization certificate for the transaction is sent to the merchant. The merchant can verify the correctness of the transaction in real time. Our protocol is compatible with the EMV standard, which is applicable to the retail environment of numerous merchants and effectively, making EMV transactions more secure and reliable. We use numerical analysis to examine the security and performance of the protocols. We formally check the correctness of EOPMA by using the Gong-Needham-Yahalom logic.

15.
Dig Dis Sci ; 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31654313

RESUMO

BACKGROUND: Short-time usage of direct-acting antiviral agents (DAA) limited knowledge regarding histological outcomes and predictive values of noninvasive measurements in patients with hepatitis C virus (HCV) after sustained virologic response (SVR) with DAA. AIMS: This study aimed to indicate histological changes and assess predictive value of noninvasive measurements for fibrosis in these patients. METHODS: HCV patients who achieved SVR by DAA were identified. Pre- and post-SVR clinical and histological data were collected. RESULTS: Of patients, 83% (33/40), 38% (15/40) and 83% (33/40) achieved inflammation improvement, fibrosis regression and histological improvement, respectively. Liver stiffness measurements (LSM), APRI, and FIB-4 could predict post-SVR fibrosis well without significant differences. Areas under receiver operating characteristic curves of LSM, APRI, and FIB-4 were 0.78, 0.81, and 0.87 for post-SVR advanced fibrosis (≥ F4) and 0.86, 0.86, and 0.85 for post-SVR cirrhosis (≥ F5), respectively. Pre-SVR LSM, APRI, and FIB-4 values were significantly lower in patients with fibrosis regression (P = 0.003-0.012), while FIB-4 was significantly lower in patients with histological improvement (P = 0.012-0.033). Patients with higher pre-SVR Ishak scores tended to have bigger decline in APRI (P = 0.025) and FIB-4 (P = 0.024) after SVR. CONCLUSIONS: DAA could improve liver inflammation and fibrosis of HCV patients in a short time after SVR. LSM, APRI, and FIB-4 predict fibrosis well even after SVR by DAA. Most of the cutoff values for advanced fibrosis (≥ F4) and cirrhosis (≥ F5) of these noninvasive measurements decreased significantly after SVR, maybe because of the inflammation improvement.

16.
Colloids Surf B Biointerfaces ; 184: 110532, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31590051

RESUMO

In this work, a multi-stimuli responsive drug delivery system (MCHP) was designed for combinational chemotherapy and photothermal therapy (PTT). Mesoporous carbon nanoparticles (MCN) with a high loading efficiency were used as near-infrared (NIR)-responsive drug carriers. Human serum albumin (HSA) was attached to the pore openings of MCN via disulfide bonds to serve as a gatekeeper due to its biocompatibility and appropriate molecular size. To improve the dispersity and biocompatibility, the surface of the MCN was modified with polyethylene glycol (PEG). In vitro photothermal effect results showed that MCHP exhibited a power and concentration-dependent photothermal conversion capacity and a good photothermal stability. The doxorubicin (DOX) release from the MCHP/DOX system exhibited NIR/pH/reduction-responsive release properties. A cytotoxicity assay demonstrated that, under NIR irradiation, the MCHP/DOX exhibited chemo-photothermal synergistic effects with a combination index (CI) of 0.643. The biodistribution of DOX in vivo indicated that an NIR laser can prolong the retardation time of DOX in tumor sites. In vivo antitumor experiments showed that MCHP/DOX with NIR irradiation had the highest tumor inhibition rate against 4T1 tumors in mice. This work suggested that MCHP could be explored as a multi-responsive drug release platform for combinational photothermo-chemotherapy.

17.
Mol Cancer ; 18(1): 147, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31651347

RESUMO

Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide and the second most lethal human cancer. A portion of patients with advanced HCC can significantly benefit from treatments with sorafenib, adriamycin, 5-fluorouracil and platinum drugs. However, most HCC patients eventually develop drug resistance, resulting in a poor prognosis. The mechanisms involved in HCC drug resistance are complex and inconclusive. Human transcripts without protein-coding potential are known as noncoding RNAs (ncRNAs), including microRNAs (miRNAs), small nucleolar RNAs (snoRNAs), long noncoding RNAs (lncRNAs) and circular RNA (circRNA). Accumulated evidences demonstrate that several deregulated miRNAs and lncRNAs are important regulators in the development of HCC drug resistance which elucidates their potential clinical implications. In this review, we summarized the detailed mechanisms by which miRNAs and lncRNAs affect HCC drug resistance. Multiple tumor-specific miRNAs and lncRNAs may serve as novel therapeutic targets and prognostic biomarkers for HCC.

18.
Nanotechnology ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31658451

RESUMO

High responsivity, fast response time, ultra-wide detection spectrum are pursuing goals for state-of-art photodetectors. Cd3As2, as a three-dimensional (3D) Dirac semimetal, has zero-bandgap, high light absorption rate in broad spectral region, and higher mobility than graphene at room temperature. However, photoconductive detectors based Cd3As2 suffer low quantum efficiency due to the absence of high built-in field. Here, Cd3As2 nanoplate/multilayer MoS2 heterojunction photodetector was fabricated and achieved a quite high responsivity of 2.7×103 A/W at room temperature. The photodetector exhibits a short response time of in broad spectra region from ultraviolet (365 nm) to short-wavelength-infrared (1550 nm) and reached 65 µs at 650nm. This work provides a great potential solution for high-performance photodetector and broadband imaging by combining 3D Dirac semi-metal materials with semiconductor materials.

19.
J Am Chem Soc ; 141(44): 17629-17636, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31600074

RESUMO

This study describes the first use of a silicon(II) complex, NHC-parent silyliumylidene cation complex [(IMe)2SiH]I (1, IMe = :C{N(Me)C(Me)}2) as a versatile catalyst in organic synthesis. Complex 1 (loading: 10 mol %) was shown to act as an efficient catalyst (reaction time: 0.08 h, yield: 94%, TOF = 113.2 h-1; reaction time: 0.17 h, yield: 98%, TOF = 58.7 h-1) for the selective reduction of CO2 with pinacolborane (HBpin) to form the primarily reduced formoxyborane [pinBOC(═O)H]. The activity is better than the currently available base-metal catalysts used for this reaction. It also catalyzed the chemo- and regioselective hydroboration of carbonyl compounds and pyridine derivatives to form borate esters and N-boryl-1,4-dihydropyridine derivatives with quantitative conversions, respectively. Mechanistic studies show that the silicon(II) center in complex 1 activated the substrates and then mediated the catalytic hydroboration. In addition, complex 1 was slightly converted into the NHC-borylsilyliumylidene complex [(IMe)2SiBpin]I (3) in the catalysis, which was also able to mediate the catalytic hydroboration.

20.
Nat Chem ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31636391

RESUMO

In an effort to obtain the maximum atom efficiency, research on heterogeneous single-atom catalysts has intensified recently. Anchoring organometallic homogeneous catalysts to surfaces creates issues with retaining mononuclearity and activity, while the several techniques developed to prepare atomically dispersed precious metals on oxide supports are usually complex. Here we report a facile one-pot synthesis of inorganometallic mononuclear gold complexes formed in alkaline solutions as robust and versatile single-atom gold catalysts. The complexes remain intact on impregnation onto supports or after drying in air to give a crystalline powder. They can be used to interrogate the nuclearity of the catalytically active gold site for reactions known to be catalysed by oxidized gold species. We show that the [Au1-Ox]- cluster directs the heterogeneous coupling of two methanol molecules to methyl formate and hydrogen with a 100% selectivity below 180 °C. The reaction is industrially important as well as the key step in methanol steam reforming on gold catalysts.

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