bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long non‐coding RNA NORAD functions as a microRNA‐204‐5p sponge to repress the progression of Parkinson's disease in vitro by increasing the solute carrier family 5 member 3 expression
Authors: Zhou Shufang , Zhang Dan , Guo Junnan , Chen Zhenzhen , Chen Yong , Zhang Junshi 
Published: July 2020

AbstractParkinson's disease (PD) is one of the most common neurodegenerative disorders. Long non‐coding RNAs have important regulatory values in various human diseases. Non‐coding RNA Activated by DNA Damage (NORAD) was reported to regulate PD progression in vitro, but its functional mechanism is fully unknown. We used 1‐methyl‐4‐phenylpyridinium (MPP+) to establish the cell‐based PD model. NORAD, microRNA‐204‐5p (miR‐204‐5p), and solute carrier family 5 member 3 (SLC5A3) levels were quantified using the quantitative real‐time polymerase chain reaction. Cell viability and apoptosis were determined by Cell Counting Kit‐8 and flow cytometry, respectively. The protein levels were analyzed via western blot. Cytotoxicity was assessed by the released lactate dehydrogenase level in cell supernatant. Oxidative stress and inflammation were measured by the standard indicators. Dual‐luciferase reporter and RNA immunoprecipitation assays were performed for intergenic combination. First, we found that NORAD was obviously reduced in MPP+‐treated neuroblastoma cells and lightened the MPP+‐induced cytotoxicity, oxidative stress, and inflammatory response. Then, NORAD was shown to be a miR‐204‐5p sponge and avoided the injury induced by MPP+ in neuroblastoma cells via targeting miR‐204‐5p. SLC5A3 was a miR‐204‐5p target and could be regulated by NORAD/miR‐204‐5p axis. SLC5A3 knockdown assuaged the anti‐miR‐204‐5p‐induced protection for neuroblastoma cells from MPP+. Altogether, NORAD played a neuroprotective role against the progression of MPP+‐induced PD model in neuroblastoma cells relying on the miR‐204‐5p/SLC5A3 axis. This study afforded the clear elaboration on the PD pathomechanism concerning NORAD.
Obesity Represses CYP2R1, the Vitamin D 25‐Hydroxylase, in the Liver and Extrahepatic Tissues
Authors: Elkhwanky Mahmoud‐Sobhy , Kummu Outi , Piltonen Terhi T , Laru Johanna , Morin‐Papunen Laure , Mutikainen Maija , Tavi Pasi , Hakkola Jukka 
Published: July 2020

ABSTRACTLow plasma level of 25‐hydroxyvitamin D (25‐OH‐D), namely vitamin D deficiency, is associated with obesity and weight loss improves 25‐OH‐D status. However, the mechanism behind obesity‐induced vitamin D deficiency remains unclear. Here, we report that obesity suppresses the expression of cytochrome P450 (CYP) 2R1, the main vitamin D 25‐hydroxylase, in both mice and humans. In humans, weight loss induced by gastric bypass surgery increased the expression of CYP2R1 in the s.c. adipose tissue suggesting recovery after the obesity‐induced suppression. At the same time, CYP27B1, the vitamin D 1α‐hydroxylase, was repressed by the weight loss. In a mouse (C57BL/6N) model of diet‐induced obesity, the plasma 25‐OH‐D was decreased. In accordance, the CYP2R1 expression was strongly repressed in the liver. Moreover, obesity repressed the expression of CYP2R1 in several extrahepatic tissues, the kidney, brown adipose tissue, and testis, but not in the white adipose tissue. Obesity had a similar effect in both male and female mice. In mice, obesity repressed expression of the vitamin D receptor in brown adipose tissue. Obesity also upregulated the expression of the vitamin D receptor and CYP24A1 in the s.c. adipose tissue of a subset of mice; however, no effect was observed in the human s.c. adipose tissue. In summary, we show that obesity affects CYP2R1 expression both in the mouse and human tissues. We suggest that in mouse the CYP2R1 repression in the liver plays an important role in obesity‐induced vitamin D deficiency. Currently, it is unclear whether the CYP2R1 downregulation in extrahepatic tissues could contribute to the obesity‐induced low plasma 25‐OH‐D, however, this phenomenon may affect at least the local 25‐OH‐D concentrations. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
Local anesthetic articaine ameliorates LPS‐induced acute kidney injury via inhibition of NF‐ĸB activation and the NLRP3 inflammasome pathway
Authors: Zhao Guanjie , Lu Shan , Li Linlin , Fan Xiaodi 
Published: July 2020

AbstractThe present study was conducted to determine the protective effect of articaine (ART) in an lipopolysaccharide (LPS)‐induced acute kidney injury (AKI) animal model. The results suggest ART causes a significant decrease in serum blood urea nitrogen, creatinine, and serum cystatin C level, showing a protective effect against LPS‐induced AKI. This has been further supported by histopathological findings of kidney tissues. The level of tumor necrosis factor‐α, interleukin (IL)‐6, and IL‐1β in serum and kidney tissues was remarkably inhibited by ART in a dose‐dependent manner. ART causes a significant reduction of malondialdehyde and increases the activities of glutathione and superoxide dismutase with an increase in dose as compared to the LPS‐treated group. Moreover, the ART‐treated group showed dose‐dependent inhibition of LPS‐induced nuclear factor‐κB activation and TLR4 expression as confirmed by Western blot analysis. The level of Bcl‐2 family genes (Bcl‐2 and Bax) was restored near to normal by ART. Collectively, all the above results indicated that ART had protective effects against LPS‐induced AKI by blocking inflammatory and oxidative responses.
Inhibition of the catalytic subunit of DNA‐dependent protein kinase (DNA‐PKcs) stimulates osteoblastogenesis by potentiating bone morphogenetic protein 2 (BMP2) responses
Authors: Farhat Theresa , Dudakovic Amel , Chung Jay H. , van Wijnen Andre J. , St‐Arnaud René 
Published: July 2020

AbstractThe catalytic subunit of DNA‐dependent protein kinase (DNA‐PKcs) is a pleiotropic enzyme involved in DNA repair, cell cycle control, and transcription regulation. A potential role for DNA‐PKcs in the regulation of osteoblastogenesis remains to be established. We show that pharmacological inhibition of DNA‐PKcs kinase activity or gene silencing of Prkdc (encoding DNA‐PKcs) in murine osteoblastic MC3T3‐E1 cells and human adipose‐derived mesenchymal stromal cells markedly enhanced osteogenesis and the expression of osteoblast differentiation marker genes. Inhibition of DNA‐PKcs inhibited cell cycle progression and increased osteogenesis by significantly enhancing the bone morphogenetic protein 2 response in osteoblasts and other mesenchymal cell types. Importantly, in vivo pharmacological inhibition of the kinase enhanced bone biomechanical properties. Bones from osteoblast‐specific conditional Prkdc‐knockout mice exhibited a similar phenotype of increased stiffness. In conclusion, DNA‐PKcs negatively regulates osteoblast differentiation, and therefore DNA‐PKcs inhibitors may have therapeutic potential for bone regeneration and metabolic bone diseases.
The influence of two land‐surface hydrology schemes on the terrestrial carbon cycle of Africa: A regional climate model study
Authors: Anwar Samy A. , Diallo Ismaila 
Published: July 2020

AbstractTwo 16‐year simulations were conducted to study the influence of two runoff schemes [the default one is TOPMODEL (hereafter referred as TOP) and the other one is the variable infiltration capacity (VIC)] with vegetation is being interactive [by enabling the carbon–nitrogen (CN) module] on the terrestrial carbon cycle fluxes of Africa using the regional climate model—RegCM4. The first simulation was labelled as CN‐TOP, while the second simulation was hereafter referred to as CN‐VIC. The results were evaluated and compared against various observation‐based satellites and reanalysis products. Results showed that the CN‐TOP overestimates leaf area index (LAI) and slightly underestimates the terrestrial carbon fluxes in comparison with the reference product; meanwhile, the CN‐VIC severely underestimates both LAI and terrestrial fluxes particularly over the Congo basin. In addition, the CN‐VIC shows a superior performance for simulating the net ecosystem exchange (NEE) than when it is simulated by the CN‐TOP. In summary, the coupled RegCM4‐CLM45‐CN‐VIC model can be recommended for future studies of NEE over Africa. To obtain robust results for simulating the terrestrial carbon fluxes especially the NEE; it is highly recommended to calibrate the four parameters of the VIC surface data set over Africa particularly over the Congo basin against in‐situ observations.
Reconstruction technique following total laryngectomy affects swallowing outcomes
Authors: Harris Brianna N. , Hoshal Steven G. , Evangelista Lisa , Kuhn Maggie 
Published: July 2020

AbstractObjectivesHow reconstruction affects function following total laryngectomy is unclear. This study seeks to determine whether reconstruction method is associated with differences in swallowing outcomes.MethodsRetrospective review of reconstruction technique in patients undergoing TL was compared by pharyngeal transit time (PTT), patient‐reported dysphagia (EAT‐10), and diet‐tolerated (FOIS).ResultsNinety‐five patients met inclusion criteria, with 40 patients (42.1%) undergoing primary closure and 55 patients (57.9%) undergoing tissue transfer. There was no difference in EAT‐10 scores between the groups (P = .09). There was a significantly higher proportion of patients achieving oral diet (FOIS >3) with primary closure (P = .003). Patients undergoing PMC vs free flap had similar rates of g‐tube dependency. Primary closure had the shortest PTT (1.89 seconds) compared to free flap (3.47‐4.65 seconds) or PMC (5.1 seconds; P = .035).ConclusionsWhen primary closure is achievable, these results suggest improved swallowing outcomes with better tolerance of oral diet and shorter pharyngeal transit times.Level of evidenceIV
Hot and sick? Impacts of warming and a parasite on the dominant zooplankter of Lake Baikal
Authors: Ozersky Ted , Nakov Teofil , Hampton Stephanie E. , Rodenhouse Nicholas L. , Woo Kara H. , Shchapov Kirill , Wright Katie , Pislegina Helena V. , Izmest'eva Lyubov R. , Silow Eugene A. , Timofeev Maxim A. , Moore Marianne V. 
Published: July 2020

AbstractClimate warming impacts ecosystems through multiple interacting pathways, including via direct thermal responses of individual taxa and the combined responses of closely interacting species. In this study, we examined how warming and infection by an oomycete parasite (Saprolegnia) affect the dominant zooplankter of Russia's Lake Baikal, the endemic copepod Epischurella baikalensis. We used a combination of laboratory experiments, long‐term monitoring data, and population modeling. Experiments showed a large difference in the thermal optima of host and parasite, with strong negative effects of warm temperatures on E. baikalensis survival and reproduction and a negative effect of Saprolegnia infection on survival. Saprolegnia infection had an unexpected positive effect on E. baikalensis reproductive output, which may be consistent with fecundity compensation by females exposed to the parasite. Long‐term monitoring data suggested that Saprolegnia infections were most common during the warmest periods of the year. Population models, parameterized with experimental and literature data, correctly predicted the timing of Saprolegnia epizootics, but overestimated the negative effect of warming on E. baikalensis populations. Models suggest that diel vertical migration may allow E. baikalensis to escape the negative effects of increasing temperatures and parasitism and enable E. baikalensis to persist in the face of moderate warming of Lake Baikal. Our results contribute to understanding of how warming and parasitism interact to affect the pelagic ecosystems of cold lakes and oceans and how the consequences of these interacting stressors can vary seasonally, spatially, and interannually.
Photosynthetic energy conversion efficiency in the West Antarctic Peninsula
Authors: Sherman Jonathan , Gorbunov Maxim Y. , Schofield Oscar , Falkowski Paul G. 
Published: July 2020

AbstractThe West Antarctic Peninsula (WAP) is a highly productive polar ecosystem where phytoplankton dynamics are regulated by intense bottom‐up control from light and iron availability. Rapid climate change along the WAP is driving shifts in the mixed layer depth and iron availability. Elucidating the relative role of each of these controls and their interactions is crucial for understanding of how primary productivity will change in coming decades. Using a combination of ultra‐high‐resolution variable chlorophyll fluorescence together with fluorescence lifetime analyses on the 2017 Palmer Long Term Ecological Research cruise, we mapped the temporal and spatial variability in phytoplankton photophysiology across the WAP. Highest photosynthetic energy conversion efficiencies and lowest fluorescence quantum yields were observed in iron replete coastal regions. Photosynthetic energy conversion efficiencies decreased by ~ 60% with a proportional increase in quantum yields of thermal dissipation and fluorescence on the outer continental shelf and slope. The combined analysis of variable fluorescence and lifetimes revealed that, in addition to the decrease in the fraction of inactive reaction centers, up to 20% of light harvesting chlorophyll‐protein antenna complexes were energetically uncoupled from photosystem II reaction centers in iron‐limited phytoplankton. These biophysical signatures strongly suggest severe iron limitation of photosynthesis in the surface waters along the continental slope of the WAP.
Experimental and theoretical studies of cinnamyl alcohol as a novel corrosion inhibitor for copper foils in rolling oil
Authors: Zhao Zhangliang , Sun Jianlin , Tang Huajie , Yan Xudong 
Published: July 2020

AbstractCinnamyl alcohol (CA) was added to the rolling oil of copper foils as a novel corrosion inhibitor, and its anticorrosion performance and mechanism were studied using potentiodynamic polarization and electrochemical impedance spectroscopy. Microstructure and chemical composition of the copper electrode surface were analyzed by scanning electron microscopy, energy‐dispersive spectroscopy, and X‐ray photoelectron spectroscopy. The results showed that CA acted as a mixed‐type inhibitor, and the maximum inhibition efficiency of 87.7% was achieved at 2.4 mM. Moreover, a protective film was formed on the copper surface, which attributed to the C–OH groups in the CA molecule. The absorption of CA on the copper surface was physisorption, which conformed to Langmuir adsorption isotherm, with a standard adsorption free energy of −11.38 kJ/mol. In the presence of CA, some flaky corrosion products changed into granular corrosion products. The synergistic effect of the granular corrosion products (copper chloride hydroxide) and the CA film further decreased the corrosion rate.
The “Superlubricity State” of Carbonaceous Fillers on Polymer Composites
Authors: Ferreira Eder H. C. , de Lima Lucas P. , Fechine Guilhermino J. M. 
Published: July 2020

AbstractIn 2019 Ferreira et al. observed for the first time the influence of the superlubricity phenomenon of platelet‐like fillers on the properties of high molecular weight polyethylene (HMWPE) in the molten state. At the time, the study was carried out in the solid state of the polymer, analyzing the influence of the superlubricity phenomenon of oxide graphene and oxide graphite (GrO) agglomerates on the mechanical properties of the HMWPE. It was observed that the agglomerates, due to their superlubricity state, toughen the HMWPE polymer matrix. Here, mechanical tests (tensile), X‐ray microtomography, and scanning electron microscopy are carried out to elucidate this phenomenon. The same is observed for polystyrene containing very poorly dispersed GrO. The results presented here are a paradigm shift, as it has always been thought that the presence of agglomerates is harmful, but the opposite is proven here. In general, this paper can contribute a lot to the development of new composites and nanocomposites based on fillers that present the superlubricity phenomenon.
Polyelectrolyte Translocation through a Corrugated Nanopore
Authors: Nagarajan Karthik , Chen Shing Bor 
Published: July 2020

AbstractThe problem of slowing down the rate of DNA translocation through a nanopore so as to facilitate detection of the genetic information remains a major challenge. In this study, the effectiveness of employing corrugated nanopores to reduce the polymer translocation velocity is investigated using dissipative particle dynamics (DPD) simulations. The average translocation time, <τ>, increases with the pore length and extent of variation of the pore cross‐sectional area. A systematic comparison of <τ> between flat and corrugated nanopores with walls that are either neutral or attractive for the polymer is performed. The value of <τ> for a corrugated nanopore with an attractive wall is 158% greater than that for a flat pore with a neutral wall. The extent of increase in <τ> obtained by manipulating either the geometry of the pore or the nature of its interaction with the polymer alone is significantly smaller. This is because the combined effect of monomer‐pore interactions and the spatial variation of the electric field strength significantly slows down the entry and escape of the chain from the pore.
Kinetics and thermal studies for the copolymerization of styrene and methyl methacrylate by incorporation of mesoporous diatomite
Authors: Khezri K. , Fazli Y. 
Published: July 2020

AbstractActivators generated by electron transfer (AGET) for atom transfer radical copolymerization (ATRP) was employed to synthesize tailor‐made random poly (styrene‐co‐methyl methacrylate)/mesoporous kieselgur nanocomposites. Some inherent features of the mesoporous kieselgur platelets were studied by nitrogen adsorption/desorption isotherm and transmission electron microscopy images. Conversion and molecular weight determinations were carried out using gas chromatography and size exclusion chromatography respectively. Addition of 3 wt.% mesoporous kieselgur platelets results in increments of conversion from 72 % to 87 % and molecular weight of copolymer chains from 15986 g mol−1 to 18564 g mol−1 respectively; however, polydispersity index values increases from 1.19 to 1.48. Increasing thermal stability of the nanocomposites is demonstrated by thermogravimetric analysis. Differential scanning calorimetry shows an increase in glass transition temperature from 70.6 °C to 75.7 °C by adding 3 wt.% of mesoporous kieselgur platelets.
A novel mixing method for powder metallurgy copper‐carbon nanotube composites
Authors: Özgün Ö. , Bulut C. 
Published: July 2020

AbstractIn this study, copper matrix composite materials with different ratios of carbon nanotubes were produced. The biggest problem faced in the production of carbon nanotube‐reinforced composites is that carbon nanotubes do not distribute homogeneously in the matrix. A novel mixing technique was applied to overcome this problem. Hot pressing was used in sample production. A second high‐pressure densification process was applied following the hot pressing process for enhancing the properties. The properties of both the hot‐pressed specimens and the specimens to which a second high‐pressure densification process was applied were characterized with the density measurements, microstructure examinations, and mechanical tests. The microstructure examinations showed that carbon nanotubes could be distributed homogeneously in the copper matrix with the mixing process applied. It was found out that the high‐pressure densification process applied following the hot‐pressing process increased the relative density and thus, all mechanical properties.
Fluid flow behavior and solidification process of welding pool under rapid cooling condition based on cellular automata‐lattice Boltzmann method (CA‐LBM) couple model
Authors: Shi F. , Zheng Z.T. , He M. , Lei Y.F. , Guo D.H. , Yu J.L. 
Published: July 2020

AbstractBased on the basic principle of lattice Boltzmann method (LBM), this paper first establishes a numerical model for simulating the evolution process of flow field, temperature field and concentration field. Then the cellular automata‐lattice Boltzmann method (CA‐LBM) coupling model is established to simulate the solidification process of welding pool. Finally, the solidification process of the welding pool under different rapid cooling powers is analyzed. It is found that the solidification process of the welding pool is significantly correlated with the magnitude of the rapid cooling power. As the rapid cooling power increases, the maximum temperature, the temperature interval and the size of the welding pool decrease, which lead to the Marangoni convection effect in the welding pool increases obviously and the unevenness of the concentration field is reduced. Meanwhile, due to the increase in the degree of supercooling, the nucleation rate increases. Finally, under the combined action, the microstructure of the weld is refined. The results of the coupling model accurately reflect the complex changes of the physical fields in the solidification process of welding pool under different cooling power. It lays a foundation for solving practical engineering problems in large calculation area.
Full‐count PET recovery from low‐count image using a dilated convolutional neural network
Authors: Spuhler Karl , Serrano‐Sosa Mario , Cattell Renee , DeLorenzo Christine , Huang Chuan 
Published: July 2020

PurposePositron emission tomography (PET) is an essential technique in many clinical applications that allows for quantitative imaging at the molecular level. This study aims to develop a denoising method using a novel dilated convolutional neural network (CNN) to recover full‐count images from low‐count images.MethodsWe adopted similar hierarchical structures as the conventional U‐Net and incorporated dilated kernels in each convolution to allow the network to observe larger, more robust features within the image without the requirement of downsampling and upsampling internal representations. Our dNet was trained alongside a U‐Net for comparison. Both models were evaluated using a leave‐one‐out cross‐validation procedure on a dataset of 35 subjects (~3500 slabs), which were obtained from an ongoing 18F‐Fluorodeoxyglucose (FDG) study. Low‐count PET data (10% count) were generated by randomly selecting one‐tenth of all events in the associated listmode file. Analysis was done on the static image from the last 10 minutes of emission data. Both low‐count PET and full‐count PET were reconstructed using ordered subset expectation maximization (OSEM). Objective image quality metrics, including mean absolute percent error (MAPE), peak signal‐to‐noise ratio (PSNR), and structural similarity index metric (SSIM), were used to analyze the deep learning methods. Both deep learning methods were further compared to a traditional Gaussian filtering method. Further, region of interest (ROI) quantitative analysis was also used to compare U‐Net and dNet architectures.ResultsBoth the U‐Net and our proposed network were successfully trained to synthesize full‐count PET images from the generated low‐count PET images. Compared to low‐count PET and Gaussian filtering, both deep learning methods improved MAPE, PSNR, and SSIM. Our dNet also systematically outperformed U‐Net on all three metrics (MAPE: 4.99 ± 0.68 vs 5.31 ± 0.76, P < 0.01; PSNR: 31.55 ± 1.31 dB vs 31.05 ± 1.39, P < 0.01; SSIM: 0.9513 ± 0.0154 vs 0.9447 ± 0.0178, P < 0.01). ROI quantification showed greater quantitative improvements using dNet over U‐Net.ConclusionThis study proposed a novel approach of using dilated convolutions for recovering full‐count PET images from low‐count PET images.