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1.
Ultrason Sonochem ; 64: 105006, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32146332

RESUMO

A novel network-like magnetic nanoparticle was fabricated on a graphitic carbon nitride through a facile sonochemical route at frequency 20 kHz and power 70 W. To enhance the electrocatalytic activity of the modified materials, the graphitic carbon nitrides (g-C3N4) was prepared from melamine. Monitoring of xanthine concentration level in biological fluids is more important for clinical diagnosis and medical applications. As modified CuFe2O4/g-C3N4 nanocomposite exhibits better electrochemical activity towards the oxidation of xanthine with higher anodic current compared to other modified and unmodified electrode for the detection of xanthine with larger linear range (0.03-695 µM) and lower limit of detection (13.2 nM). To compare with these methods, the electrochemical techniques may be an alternative high sensitive method due to their simplicity and rapid detection time. In addition, the practical feasibility of the sensor was inspected with biological samples, reveals the acceptable recovery of the sensor in real samples.

2.
Cell Mol Life Sci ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170339

RESUMO

eIF4E plays key roles in protein synthesis and tumorigenesis. It is phosphorylated by the kinases MNK1 and MNK2. Binding of MNKs to eIF4G enhances their ability to phosphorylate eIF4E. Here, we show that mTORC1, a key regulator of mRNA translation and oncogenesis, directly phosphorylates MNK2 on Ser74. This suppresses MNK2 activity and impairs binding of MNK2 to eIF4G. These effects provide a novel mechanism by which mTORC1 signaling impairs the function of MNK2 and thereby decreases eIF4E phosphorylation. MNK2[S74A] knock-in cells show enhanced phosphorylation of eIF4E and S6K1 (i.e., increased mTORC1 signaling), enlarged cell size, and increased invasive and transformative capacities. MNK2[Ser74] phosphorylation was inversely correlated with disease progression in human prostate tumors. MNK inhibition exerted anti-proliferative effects in prostate cancer cells in vitro. These findings define a novel feedback loop whereby mTORC1 represses MNK2 activity and oncogenic signaling through eIF4E phosphorylation, allowing reciprocal regulation of these two oncogenic pathways.

3.
Endocrinology ; 161(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32141513

RESUMO

Follicle-stimulating hormone (FSH)-induced growth of ovarian follicles is independent of follicular vascularization. Recent evidence has indicated that follicular vascularization is critical to ovarian follicle development and survival. FSH, a gonadotropin that induces follicular growth and development, also acts as the major survival factor for antral follicles. FSH has been reported to stimulate angiogenesis in the theca layers mediated in part by the vascular endothelial growth factor A (VEGFA) and the transcription factor hypoxia inducible factor 1α (HIF-1α). However, it remains largely undetermined whether FSH-dependent growth and survival of antral follicles relies on FSH-induced vascularization. Here, we first demonstrated that induction of angiogenesis through the FSH-HIF-1α-VEGFA axis is not required for FSH-stimulated follicular growth in mouse ovary. FSH increased the total number of blood vessels in mouse ovarian follicles, which was correlated with elevated expression of VEGFA and HIF-1α in granulosa cells. In contrast, blocking of follicular angiogenesis using inhibitors against the HIF-1α-VEGFA pathway repressed vasculature formation in follicles despite FSH administration. Interestingly, by measuring follicular size and ovarian weight, we found that the suppression of angiogenesis via HIF-1α-VEGFA pathway did not influence FSH-mediated follicular growth. However, inhibition of FSH-induced follicular vascularization by PX-478, a small-molecule inhibitor that suppresses HIF-1α activity, blocked ovulation and triggered atresia in large follicles. On the other hand, PX-478 injection reduced oocyte quality via impairing the meiotic apparatus, showing a prominently defective spindle assembly and actin dynamics. Collectively, our findings unveiled a vascularization-independent effect of FSH on follicular growth, whereas follicular survival, ovulation, and oocyte development relies on FSH-mediated angiogenesis in the follicles.

4.
Nanoscale ; 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32219258

RESUMO

Correction for 'A robust Mn@FeNi-S/graphene oxide nanocomposite as a high-efficiency catalyst for the non-enzymatic electrochemical detection of hydrogen peroxide' by Shaktivel Manavalan et al., Nanoscale, 2020, 12, 5961-5972.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32149501

RESUMO

The rapid development of electrochemical sensors holds great promise to serve as next generation point-of-care safety devices. However, the practical performances of electrochemical sensors are cruelly limited by stability, selectivity, and sensitivity. These issues have been well addressed by introducing rational designs into the modified electrode for achieving the required performances. Herein, we demonstrate the gadolinium oxide nanorods embedded on the graphene aerogel (GdO NRs/GA) for a highly selective electrochemical detection of carbendazim (CDM). The GdO NRs/GA nanocomposite was characterized using X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, field emission gun scanning electron microscopy, transmission electron microscopy with elemental mapping, and energy-dispersive spectrometry. The GdO NRs/GA-modified electrode shows a much improved electrochemical performance compared to other electrodes. Interestingly, the GdO NRs are strongly anchored in the GA matrix, which provides a more sufficient pathway for the rapid electron and ion transportation. On the basis of these findings, our proposed sensor achieves a wide detection range from 0.01 to 75 µM with a correlation coefficient of 0.996 and a low detection limit of 3.0 nM. Most markedly, the real-time monitoring of the proposed electrochemical sensor was proved by the successful determination of CDM in environmental samples. Our research work has opened a novel way to the rationale for the construction of highly efficient practical electrochemical sensors.

6.
Sci Total Environ ; 721: 137774, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32172123

RESUMO

The concentration and composition of suspended particulate matter provide important information for evaluating water quality and understanding the variability in the underwater light field in lakes. In this study, inherent optical property (IOP)-centered algorithms were developed to estimate the concentrations of chlorophyll-a (Chla, [mg/m3]) and suspended particulate matter (SPM, [g/m3]) and the Chla/SPM ratio (an indicator of the suspended particulate composition) of 118 lakes in the middle and lower reaches of the Yangtze and Huai Rivers (MLYHR) of China using Sentinel-3A/OLCI (Ocean and Land Colour Instrument) data collected from August 2016 to July 2018. The mean Chla concentration and Chla/SPM ratio were high in summer and low in winter, while the mean SPM peaked in winter and decreased in summer. The 94 lakes in the Yangtze River basin had a higher mean Chla concentration (30.94 ± 14.84) and Chla/SPM ratio (0.97 × 10-3 ± 0.60 × 10-3), but a lower mean SPM (44.87 ± 12.61) than the 24 lakes in the Huai River basin (Chla: 27.35 ± 12.18, Chla/SPM: 0.79 × 10-3 ± 0.48 × 10-3, SPM: 47.31 ± 13.40). Regarding the mean values of each lake, Chla and Chla/SPM ratio correlated well with temperature, whereas the wind speed and precipitation had little effect on the variations of suspended particulate matter. Moreover, shipping transportation and sand dredging activities affected the spatial distribution of Chla, SPM, and Chla/SPM in several large lakes (e.g., Lake Poyang and Lake Dongting). Chla/SPM related well with other proxies that express the suspended particulate composition, and had a significant correlation with the Chla-specific absorption coefficient of phytoplankton at 443 nm (aph⁎(443)). The remotely sensed concentration and composition of suspended particulate matter can provide a comprehensive reference for water quality monitoring and expand our knowledge of the trophic status of the lakes.

7.
J Clin Lab Anal ; : e23315, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32207860

RESUMO

BACKGROUND: Sustaining proliferation is the most fundamental step for breast cancer tumor genesis. Accelerated proliferation is usually linked to the uncontrolled cell cycle. However, the internal and external factors linked to the activation of breast cancer cell cycle are still to be investigated. METHODS: quantitative PCR (qPCR) and Western blotting assay were used to detect the expression of potassium channel tetramerization domain containing 12 (KCTD12) in breast cancer. MTT and colony formation assays were performed to evaluate the effect of KCTD12 on cell proliferation of breast cancer. Anchorage-independent growth assay was used to examine the in vitro tumorigenesis of breast cancer cells. Flow cytometry assay, qPCR, and Western blotting were used to investigate the detailed mechanisms of KCTD12 on breast cancer progression. RESULTS: Herein, the result showed that the level of KCTD12 is significantly decreased in breast cancer tissues and cells, and lower level of KCTD12 predicts poorer survival for patients with breast cancer. Further cell function tests illustrated that downregulation of KCTD12 significantly promotes cell proliferation and in vitro tumor genesis. Besides, molecular biologic experiments showed that downregulation of KCTD12 can enhance the G1/S transition through activating the AKT/FOXO1 signaling. CONCLUSION: Our study inferred that downregulation of KCTD12 can be a novel factor for poor prognosis in breast cancer.

8.
Macromol Rapid Commun ; : e2000035, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32125049

RESUMO

1D polymer nanomaterials have attracted significant interest in recent years because of their unique properties and promising applications in various fields. It is, however, still a challenge to fabricate polymer nanoarrays with desired sizes and controlled morphologies. Here, an unprecedented approach, the laser-assisted nanowetting (LAN) method, to selectively fabricate polymer nanoarrays is presented. Polystyrene (PS) is blended with gold nanorods (AuNRs), which are used to absorb the energy from the laser. After the blend films are brought in contact with AAO templates, the AuNRs at regions shone by the laser beams absorb the energy and heat the surrounding polymer chains, resulting in the formation of PS/AuNRs arrays in selected areas. This work paves a new research direction for developing template-based polymer nanomaterials.

9.
Endocr Pract ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32045295

RESUMO

PURPOSE: Comprehensive evidence comparing different medications for acromegaly is scarce. The aim of this study was to perform a network meta-analysis based on evidence from both randomized trials and observational studies of medical treatments for acromegaly. METHODS: Electronic databases were searched for both observational studies and randomized trials that enrolled acromegaly patients treated with medications of interest. Simulated trials were generated by a machine learning algorithm, and then synthesized with Bayesian random-effects network meta-analyses. The main outcome was the rate of insulin-like growth factor-I (IGF-I) control after medical treatment. RESULTS: We included 90 studies (100 arms, 4523 patients) before matching. After matching, 28 simulated trials were generated. Balance of matched arms was checked by spatial distance and correlation matrix. Co-treatment with somatostatin receptor ligands and pegvisomant was the most effective treatment compared with other treatments. In unselected patients, pegvisomant was better than octreotide long-acting release (logOR, 0.85, 95% credibility interval [CrI], 0.05 to 1.65) or lanreotide (logOR, 1.09, 95% CrI, 0.05 to 2.14) and the mean absolute IGF-I control rate ranged from 40% to 60%. While in partially responsive patients, co-treatment with somatostatin receptor ligands and pegvisomant was similar to pegvisomant monotherapy, ranking as the most two effective treatments, and the mean absolute IGF-I control rate was over 60%. CONCLUSIONS: Our analysis suggested that the combination of data from observational studies and randomized trials in network meta-analysis was feasible. The findings of this network meta-analysis provided robust evidence supporting the current guidelines in treatment strategy for acromegaly.

10.
J Mol Histol ; 51(1): 55-65, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32006186

RESUMO

p53 is known to advance the cell arrest and cell senescence in human tumors. In this study, we displayed that osteogenic ability of p53-knockout (p53-/-) mice was significantly increased in the tooth extraction socket compared with wild-type (WT) counterparts. Bone marrow mesenchymal stem cells (BM-MSCs) from mandibular were collected and exhibited with elevated proliferation potential and colony-forming units compared with the control, as well as stronger mineral deposits and osteogenic markers. Besides, the bone mass and bone parameter in p53-/- mice were markedly enhanced compared with the counterpart after extractions by micro-CT. Masson's trichrome staining and immunohistochemistry also revealed that new bone filling and osterix/osteocalcin (Osx/OCN)-immunopositive staining in p53-/- mice were remarkably increased at each time point. Furthermore, consistent with the enhanced osteogenic markers, the angiogenic marker of blood vessels (alpha smooth muscle actin, α-SMA) was significantly elevated in p53-/- mice in contrast to WT mice. Importantly, we found that the osteoclast numbers exhibited an increased trend in p53-/- mice compared with WT mice during socket healing. Collectively, our result suggest that p53 deficiency could promote the osteogenesis and angiogenesis in the tooth extraction socket and might lend possibility for p53-based therapeutic approaches in acceleration of extraction bone healing.

11.
Ultrason Sonochem ; 64: 105014, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32078909

RESUMO

This work described the sonohydrolysis of Bi(NO3)3 into Bi2O3 and simultaneous sonochemical exfoliation of graphite into graphene sheets in the alkaline environment and its electocatalytic performance towards the detection of anti-depression drug imipramine (IMPR). The ultrasound (37/80 kHz; 60 W) effectively hydrolyzed the Bi(NO3)3 into a single crystalline monoclinic phase of Bi2O3 nanotiles in the alkaline condition. And also, the sonochemical reaction condition can trigger the lamellar particles on the graphite bulk surface and allowed to exfoliated the graphite (EG) into graphene nanosheets as well. The material characterizations are done by XRD, Raman, FESEM, and HRTEM. It shows the α-Bi2O3 nanotiles along with EG nanosheets with high crystallinity and low defects. The (0 0 2) plane in XRD confirms the high crystalline nature of EG. The monoclinic stretching vibrations (90-600 cm-1) confirms the Raman modes of Bi2O3. The prepared Bi2O3-EG composites are subjected to the electrochemical determination of IMPR which revealed appreciable analytical performances. The results showed that the Bi2O3-EG exhibits better results in the 3 h sonication process. Bi2O3-EG-3 exhibited a good linear range (0.02-82.3 µM) and an acceptable limit of detection (6 nM). And also Bi2O3-EG-3 exhibits the significant tolerance limit when compared to other potential interfering compounds.

12.
Ultrason Sonochem ; 64: 105007, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32092696

RESUMO

Binary metal oxides (La2O3@SnO2) decorated reduced graphene oxide nanocomposite was synthesized by ultrasound process in an environmentally benign solvent with a working frequency of 25 and 40 kHz (6.5 l200 H, Dakshin, India and maximum input power 210 W). Further, to enhance the electrocatalytic activity, the reduced graphene oxide (rGO) was prepared from graphene oxide by ultrasonication method. As prepared La2O3@SnO2/rGO was scrutinized using XRD, TEM, EDX and quantitative test for the structural and morphology properties. As modified La2O3@SnO2/rGO nanocomposite exhibits better electrochemical activity towards the oxidation of methyl nicotinate with higher anodic current compared to other modified and unmodified electrode for the detection of methyl nicotinate with larger linear range (0.035-522.9 µM) and lower limit of detection (0.0197 µM). In addition, the practical feasibility of the sensor was inspected with biological samples, reveals the acceptable recovery of the sensor in real samples.

13.
Ultrason Sonochem ; 64: 105008, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32106067

RESUMO

Thermo-responsive polymer nanocomposite based on poly (styrene-co-N-isopropylacrylamide) hybrid tungsten dioxide (WO2@PS-co-PNIPAM) was synthesized by a facile ultrasonic irradiation (Frequency; 20 kHz, power; 180 W, calorimetrically determined power; 5.73 W in the bath, and Type; probe) method in the presence of water as inisolv. The as-synthesized WO2@PS-co-PNIPAM modified glassy carbon electrode (WO2@PS-co-PNIPAM/GCE) was acting as a reversibly switched detection for the electrooxidation of metoprolol (MTP), with the thermal stimuli response of the PNIPAM. In below lower critical solution temperature (LCST), the PS-co-PNIPAM expanded to embed the electroactive sites of WO2, and the MTP could not proceed via the polymer to attain electronic transfer, indicating the "off" state. Rather, in above LCST, the PS-co-PNIPAM shrank to reveal electroactive sites and expand cyclic voltammetric background peak currents, the MTP was capable to undergo electro-oxidation reaction usually and produce the response current, indicating "on" state. Additionally, the proposed sensor had excellent sensitivity (2.21 µA µM-1 cm-2), wide dynamic range (0.05-306 µM), and a low limit of detection of 0.03 µM for MTP. Intriguingly, the fabricated sensor demonstrates the good selectivity towards the detection of MTP among the possible interfering compounds. Eventually, the WO2@PS-co-PNIPAM/GCE has been utilized in the analysis of MTP in human blood serum samples.

15.
Nanoscale ; 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32108852

RESUMO

Exploring high-efficiency, stable, and cost-effective electrocatalysts for electrochemical activities is greatly desirable and challenging. Herein, a newly designed hybrid catalyst with manganese-doped FeNi-S encapsulated into graphene oxide (Mn@FeNi-S/GO) with unprecedented electrocatalytic activity was developed by simple one-step heat treatment followed by sonication. X-ray powder diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), and N2 sorption isotherm demonstrated the successful formation of Mn@FeNi-S/GO. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) further confirmed the kinetic-favourable adsorption of hydrogen peroxide (H2O2) onto the surface sites of Mn@FeNi-S/GO. Additionally, the synergetic effects between Mn@FeNi-S and GO are regarded as significant contributors to an efficient electron transfer path, and they promote the capture of H2O2 in hybrid catalysts. Under an optimal condition, a biosensor-based Mn@FeNi-S/GO electrode exhibits a high sensitivity of 8.929 µA µM-1 cm-2 and a detection limit of 8.84 nM with a wide detection range for H2O2 and excellent selectivity; also, it is capable of online monitoring H2O2 derived from apple juice and human blood serum.

16.
Gynecol Endocrinol ; : 1-6, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070153

RESUMO

Osteoporosis is now a worldwide public health problem that seriously endangers human health, but its causes have not yet been fully clarified. Recently, increasing evidence suggested that polymorphisms in CYP19A1 gene were associated with osteoporosis risk and bone mineral density (BMD), but results remained conflicting. We herein performed a meta-analysis based on evidence currently available from the literature to make a more precise estimation of these relationships. The PubMed, Embase, Cochrane library, CNKI (China National Knowledge Infrastructure), and Wan Fang databases were searched for eligible studies. Odds ratio (OR), mean difference (MD), and 95% confidence interval (CI) were applied to assess the strength of these relationships. A total of 8 studies involving 2632 subjects were included in our meta-analysis. We observed that the AG genotype of CYP19A1 rs700518 was significantly associated with lower BMD values of lumbar spine and femoral neck (AG vs. GG: p = .001 and.01, respectively). However, this polymorphism had no obvious impacts on osteoporosis risk according to current available data. In conclusion, the present meta-analysis showed that CYP19A1 rs700518 polymorphism may be a potential candidate biomarker for osteoporosis screening, early diagnosis, and treatment, which will help improve individualized therapy of osteoporosis patients in clinics.

17.
FASEB J ; 34(3): 3631-3645, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31960530

RESUMO

In developing follicles, the granulosa cells (GCs) live in a hypoxic environment due to the devoid of blood supply. Upon hypoxic conditions, several types of mammalian cells have been reported to undergo apoptosis. Follicle-stimulating hormone (FSH) is known as the primary survival factor for antral follicles by preventing GCs apoptosis. Mitophagy is a type of organelle-specific autophagy that removes damaged or stressed mitochondria to maintain cellular health. This study provides the first evidence suggesting that FSH-mediated mitophagy protected porcine GCs from hypoxia-induced apoptosis. Our data showed that the GCs apoptosis caused by mitochondrial pathway upon hypoxia stress was markedly attenuated after FSH treatment, which was correlated with enhanced activation of mitophagy. Interestingly, FSH also stimulated mitochondrial biogenesis as suggested by increased expression of mitochondrial transcription factor A and nuclear respiratory factor 1 during hypoxia exposure. Notably, the protein level of hypoxia inducible factor-1α (HIF-1α) was significantly increased in hypoxic GCs following FSH treatment, accompanied by elevated mitophagic activity and dampened apoptotic signaling. Blocking HIF-1α inhibited mitophagy and restored hypoxia-induced apoptosis despite FSH treatment. Importantly, FSH promoted the expression of serine/threonine kinase PTEN induced putative kinase 1 (PINK1) and the E3 ligase Parkin during hypoxia stress through a HIF-1α dependent manner. This induced the mitophagic clearance of damaged mitochondria, hence inhibiting apoptosis by reducing cytochrome c releasing. The inhibition of HIF-1α and/or PINK1 using inhibitor or RNAi further confirmed the role of the FSH-HIF-1α-PINK1-Parkin-mitophagy axis in suppressing GC apoptosis under hypoxic conditions. These findings highlight a novel function of FSH in preserving GCs viability against hypoxic damage by activating HIF-1α-PINK1-Parkin-mediated mitophagy.

18.
Mol Med Rep ; 21(2): 659-666, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31974611

RESUMO

The aim of the present study was to investigate the expression of keratin 20 (KRT20) and placenta specific 8 (PLAC8) in gastrointestinal (GI) cancer with various differentiation phenotypes. The present study retrospectively investigated archived formalin­fixed paraffin­embedded tissue samples from 12 patients at different stages of GI cancer [four with gastric cancer, four with pancreatic cancer and four with colorectal cancer (CRC)]. The stages were pre­determined, according to differentiation phenotypes, by a pathologist of the Department of Pathology at Sijhih Cathay General Hospital. KRT20 and PLAC8 expression levels were assessed using immunohistochemistry. The CRC cell lines SW620 and Caco­2 were used to assess interactions between KRT20 and PLAC8 via reverse transcription­quantitative PCR. PLAC8 and KRT20 expression was observed consistently only in the well­differentiated CRC tissue samples. Low KRT20 expression levels were observed in the PLAC8 knockdown SW620 cells. In addition, there was a positive association between PLAC8 and KRT20 expression in the differentiated Caco­2 cells. According to the results of the present study, the differentiation status of GI cancer influenced KRT20 expression, particularly in CRC, which may explain why patients with well­differentiated CRC display better clinical outcomes. Therefore, the prognostic significance of KRT20 and PLAC8 may be particularly crucial for patients with CRC displaying a well­differentiated phenotype.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31990167

RESUMO

We report the rational design and implementation of a new class of gel guest-assisted, ionic covalent organic framework (COF) membranes that exhibit superior H+ conduction. The as-synthesized COFs are postmodified via a lithiation (or sodiation) treatment. The hydrophilic Li or Na ions in the COFs form a dense and extensive hydrogen-bonding network of H2O molecules with mobile H+ at the periphery, thereby transforming COFs into H+ conductors. Then, the ionic COFs are assembled into a flexible H+ conductor membrane via a gelation process, where the organic gel provides both mechanical strength and additional H+ carriers for fast H+ conduction. The final COF-based membrane exhibits an excellent H+ conductivity of 1.3 × 10-1 S cm-1 at 313 K and 98% relative humidity, which are the highest values of the COF-based H+ conductors reported until now and are even comparable with those of the typical commercial Nafion membrane. We anticipate that the two-in-one strategy would open up a porous COF-driven new molecular framework and membrane architectural design/opportunity for development of next-generation ionic conductors.

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