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Inflammatory bowel disease (IBD) mainly includes Crohn's disease (CD) and ulcerative colitis (UC). Immune disorders play an essential role in the pathogenesis of these two IBDs, but the differences in the immune microenvironment of the colon and their underlying mechanisms remain poorly investigated. Here we examined the immunological features and metabolic microenvironment of untreated individuals with IBD by multiomics analyses. Modulation of CD-specific metabolites, particularly reduced selenium, can obviously shape type 1 T helper (Th1) cell differentiation, which is specifically enriched in CD. Selenium supplementation suppressed the symptoms and onset of CD and Th1 cell differentiation via selenoprotein W (SELW)-mediated cellular reactive oxygen species scavenging. SELW promoted purine salvage pathways and inhibited one-carbon metabolism by recruiting an E3 ubiquitin ligase, tripartite motif-containing protein 21, which controlled the stability of serine hydroxymethyltransferase 2. Our work highlights selenium as an essential regulator of T cell responses and potential therapeutic targets in CD.
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Antioxidantes/farmacologia , Doença de Crohn/tratamento farmacológico , Doença de Crohn/imunologia , Selênio/farmacologia , Selenoproteína W/metabolismo , Células Th1/citologia , Diferenciação Celular/imunologia , Polaridade Celular , Colo/imunologia , Colo/patologia , Glicina Hidroximetiltransferase/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Ribonucleoproteínas/metabolismo , Células Th1/imunologia , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Although copper oxide high-temperature superconductors constitute a complex and diverse material family, they all share a layered lattice structure. This curious fact prompts the question of whether high-temperature superconductivity can exist in an isolated monolayer of copper oxide, and if so, whether the two-dimensional superconductivity and various related phenomena differ from those of their three-dimensional counterparts. The answers may provide insights into the role of dimensionality in high-temperature superconductivity. Here we develop a fabrication process that obtains intrinsic monolayer crystals of the high-temperature superconductor Bi2Sr2CaCu2O8+δ (Bi-2212; here, a monolayer refers to a half unit cell that contains two CuO2 planes). The highest superconducting transition temperature of the monolayer is as high as that of optimally doped bulk. The lack of dimensionality effect on the transition temperature defies expectations from the Mermin-Wagner theorem, in contrast to the much-reduced transition temperature in conventional two-dimensional superconductors such as NbSe2. The properties of monolayer Bi-2212 become extremely tunable; our survey of superconductivity, the pseudogap, charge order and the Mott state at various doping concentrations reveals that the phases are indistinguishable from those in the bulk. Monolayer Bi-2212 therefore displays all the fundamental physics of high-temperature superconductivity. Our results establish monolayer copper oxides as a platform for studying high-temperature superconductivity and other strongly correlated phenomena in two dimensions.
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Exosomes, one of three main types of extracellular vesicles, are ~30-100 nm in diameter and have a lipid bilayer membrane. They are widely distributed in almost all body fluids. Exosomes have the potential to regulate unknown cellular and molecular mechanisms in intercellular communication, organ homeostasis, and diseases. They are critical signal carriers that transfer nucleic acids, proteins, lipids, and other substances into recipient cells, participating in cellular signal transduction and material exchange. ncRNAs are non-protein-coding genes that account for over 90% of the genome and include microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs). ncRNAs are crucial for physiological and pathological activities in the liver by participating in gene transcription, posttranscriptional epigenetic regulation, and cellular processes through interacting with DNA, RNA, or proteins. Recent evidence from both clinical and preclinical studies indicates that exosome-derived noncoding RNAs (ncRNAs) are highly involved in the progression of acute and chronic liver diseases by regulating hepatic lipid metabolism, innate immunity, viral infection, fibrosis, and cancer. Therefore, exosome-derived ncRNAs have promising potential and clinical implications for the early diagnosis, targeted therapy, and prognosis of liver diseases.
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Exossomos , MicroRNAs , RNA Longo não Codificante , Epigênese Genética , Exossomos/genética , Exossomos/metabolismo , Fígado/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , RNA não Traduzido/genética , RNA não Traduzido/metabolismoRESUMO
We use scanning tunneling microscopy to investigate the (001) surface of a cleaved SmB6 Kondo insulator. Variable temperature dI/dV spectroscopy up to 60 K reveals a gaplike density of state suppression around the Fermi level, which is due to the hybridization between the itinerant Sm 5d band and localized Sm 4f band. At temperatures below 40 K, a sharp coherence peak emerges within the hybridization gap near the lower gap edge. We propose that the in-gap resonance state is due to a collective excitation in magnetic origin with the presence of spin-orbital coupling and mixed valence fluctuations. These results shed new light on the electronic structure evolution and transport anomaly in SmB6.
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We use scanning tunneling microscopy to investigate the doping dependence of quasiparticle interference (QPI) in NaFe1-xCoxAs iron-based superconductors. The goal is to study the relation between nematic fluctuations and Cooper pairing. In the parent and underdoped compounds, where fourfold rotational symmetry is broken macroscopically, the QPI patterns reveal strong rotational anisotropy. At optimal doping, however, the QPI patterns are always fourfold symmetric. We argue this implies small nematic susceptibility and, hence, insignificant nematic fluctuation in optimally doped iron pnictides. Since TC is the highest this suggests nematic fluctuation is not a prerequistite for strong Cooper pairing.
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The clinical features and risk factors for survival time were analysed in haemodialysis patients complicated with infective endocarditis. A total of 101 infective endocarditis (IE) patients treated at Hangzhou First People's Hospital, from January 1, 2012, to April 1, 2022, were included in the present study. Baseline demographic data and laboratory data were collected for statistical analysis of risk factors and survival time in the IE with haemodialysis group (HD-IE group, n=15) and the IE without haemodialysis group (NHD-IE group, n=86). Haemoglobin, red blood cells, C-reactive protein, procalcitonin, serum albumin, diabetes, invasive procedures, positive blood bacteria culture, heart valve calcification ratio, and left ventricular ejection fraction level were risk factors for infective endocarditis complicated with haemodialysis (P<0.05). Compared with the NHD-IE group, the HD-IE group had an obviously increased risk of mortality (χ2=6.323, P=0.012). The univariate Cox regression analysis showed that age, haemoglobin, red blood cells, serum albumin, left ventricular ejection score, longest vegetation diameter, combined hypotension and diabetes were risk factors for death; furthermore, multivariate Cox regression showed that age (HR=1.187, P=0.015), combined hypotension (HR=0.921, P=0.025) and the longest vegetation diameter (HR=9.191, P=0.004) were independent risk factors affecting the survival of patients. Collectively, the present study revealed that the mortality rate of HD-IE patients was higher than that of NHD-IE patients. Older age, hypotension, and the longest vegetation diameter were independent risk factors affecting the survival of patients. For HD-IE patients, active and effective antibiotic treatment or surgical treatment should be strongly recommended.
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We report the doping, temperature, and spatial evolutions of the electronic structure of NaFe(1-x)Co(x)As studied by scanning tunneling microscopy. In the parent state we directly observe the spin density wave gap, which exhibits unconventional features that are incompatible with simple Fermi surface nesting. The optimally doped sample has a single superconducting gap, but in the overdoped regime a novel pseudogaplike feature emerges. The pseudogaplike phase coexists with superconductivity in the ground state, persists well into the normal state, and shows strong spatial variations. The characteristics of the three distinct electronic states revealed here shed important new lights on the microscopic models for the iron-based superconductors.
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We present scanning tunneling microscopy studies of the LaOFeAs parent compound of iron pnictide superconductors. High resolution spectroscopic imaging reveals strong standing wave patterns induced by quasiparticle interference of two-dimensional surface states. Fourier analysis shows that the distribution of scattering wave vectors exhibits pronounced twofold (C(2)) symmetry, strongly reminiscent of the nematic electronic state found in CaFe(1.94)Co(0.06)As(2). The implications of these results to the electronic structure of the pnictide parent states will be discussed.
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AIM: To evaluate the effect of vitrectomy combined with scleral shortening for eyes with myopic macular retinoschisis. METHODS: Thirty-seven patients with myopic macular retinoschisis who underwent pars plana vitrectomy (PPV) combined with scleral shortening were reviewed. Axial length (AL), the height of macular retinoschisis, the height of retinal detachment if existed, the diameter of macular hole if existed and best corrected visual acuity (BCVA) were obtained. The preoperative and postoperative parameters were compared. RESULTS: At postoperative 24mo, the mean AL and height of macular retinoschisis were reduced significantly by 0.79 mm and 256.51 µm (t=8.064, P<0.0001; Z=-5.086, P<0.0001) respectively. In addition, the mean height of retinal detachment and diameter of macular hole were also reduced significantly by 365.38 µm and 183.68 µm (Z=-4.457, P=0.000008; Z=-2.983, P=0.003) respectively. Meanwhile, the postoperative BCVA was improved markedly (Z=-2.126, P=0.033). CONCLUSION: Vitrectomy combined with scleral shortening is an effective surgical method for eyes with myopic macular retinoschisis, whether or not macular hole and retinal detachment are present.
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OBJECTIVE: To investigate inhibition effects and the mechanism of EPA on the proliferation of human umbilical vascular endothelial cells (HUVEC). METHODS: Different concentrations of EPA were added to the cultured HUVEC in vitro. The time cause and does response for the inhibition the cells proliferation in all groups were measured by the MTT assay. Light absorption values and cytostasis ratios in all groups were compared. One-way ANOVA in the SPSS 13.0 version statistical software was used. The effect of EPA on cell cycle, proliferative index (PI) and apoptosis of HUVEC in vitro were observed by Flow Cytometry. chi2-test of R x C contingency table was used as a method for statistical analysis. RESULTS: When the concentration of EPA was equal to or more than 0.15 g/L, MTT assay showed a significant difference of light absorption value in the cultured cell after EPA exposure compared with control, the suppressing effects enhanced as the treatment time increased. The peak time of the inhibition of the cell proliferation induced by EPA was at 60 hours and the effect was last until 72 hours. The proliferative index in the treatment group was 23.9%, which was lower than that in the control group (26.9%). No apoptosis was found in the cell in each group. CONCLUSIONS: EPA plays an important role of inhibition of proliferation of cultured HUVEC in vitro. No apoptosis was induced by the exposure HUVEC to EPA, therefore, it suggests a potential application for clinical trial.
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Proliferação de Células/efeitos dos fármacos , Ácido Eicosapentaenoico/farmacologia , Células Endoteliais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/citologia , HumanosRESUMO
A simple and highly sensitive fluorimetric method for the determination of Cr(VI) was developed in the present paper. The method is based on the fluorescence enhancement of acridine red with Cr(VI) in the sulfuric acid medium. The effects of some experimental conditions on the determination of Cr(VI) were investigated in detail. The detection limit for Cr(VI) is 0.6 microg x L(-1), and the linear range of the determination is 2.0-32 microg x L(-1). The relative standard deviation of 11 replicate measurements is less than 2.0%. The proposed method has been successfully used to determine Cr(VI) in electroplating solution, waste chromic acid mixture, and alloy steel samples. The results obtained were compared with the certified values of Cr(VI) in standard samples and those provided by 1, 5-diphenylcarbazide method with satisfaction.
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OBJECTIVE: A study was carried out to investigate the effects of seed oil and sarcocarp oil of Hippophae rhamnoides on rats with experimental hepatocirrhosis, and comparison between the two. METHOD: A rat model of experimental hepatocirrhosis was set up by feeding CCl4. Different concentration of seed oil and sarcocarp oil of H. rhamnoides were feed to those rats for 45 d, then the changes of activity of ALT in serum and SOD in liver were measured. RESULT: Both of seed oil and sarcocarp oil can control the increase of ALT in serum and the decrease of SOD evidently, and the effect of seed oil was turn out to be a little better than sarcocarp oil. CONCLUSION: Seed oil was more effective than sarcocarp oil of H. rhamnoides in alleviating liver injury caused by CCl4.
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Hippophae , Cirrose Hepática Experimental/metabolismo , Óleos de Plantas/farmacologia , Alanina Transaminase/sangue , Animais , Intoxicação por Tetracloreto de Carbono , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Frutas/química , Hippophae/química , Fígado/enzimologia , Cirrose Hepática Experimental/etiologia , Masculino , Óleos de Plantas/isolamento & purificação , Plantas Medicinais/química , Ratos , Sementes/química , Superóxido Dismutase/metabolismoRESUMO
Electron-electron and electron-phonon interactions are two major driving forces that stabilize various charge-ordered phases of matter. In layered compound 1T-TaS2, the intricate interplay between the two generates a Mott-insulating ground state with a peculiar charge-density-wave (CDW) order. The delicate balance also makes it possible to use external perturbations to create and manipulate novel phases in this material. Here, we study a mosaic CDW phase induced by voltage pulses, and find that the new phase exhibits electronic structures entirely different from that of the original Mott ground state. The mosaic phase consists of nanometre-sized domains characterized by well-defined phase shifts of the CDW order parameter in the topmost layer, and by altered stacking relative to the layers underneath. We discover that the nature of the new phase is dictated by the stacking order, and our results shed fresh light on the origin of the Mott phase in 1T-TaS2.
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Elétrons , Fônons , Sulfetos/química , Tantálio/química , Eletrônica , Transição de Fase , TemperaturaRESUMO
Monolayer transition metal dichalcogenides MX2 (M = Mo, W; X = S) exhibit remarkable electronic and optical properties, making them candidates for application within flexible nano-optoelectronics. The ability to achieve a high optical signal, while quantitatively monitoring strain in real-time is the key requirement for applications in flexible sensing and photonics devices. Surface-enhanced Raman scattering (SERS) allows us to achieve both simultaneously. However, the SERS depends crucially on the size and shape of the metallic nanoparticles (NPs), which have a large impact on its detection sensitivity. Here, we investigated the SERS of monolayer MX2, with particular attention paid to the effect of the distribution of the metallic NPs. We show that the SERS depends crucially on the distribution of the metallic NPs and also the phonon mode of the MX2. Moreover, strong coupling between MX2 and metallic NPs, through surface plasmon excitation, results in splitting of the and modes and an additional peak becomes apparent. For a WS2-Ag system the intensity of the additional peak increases exponentially with local strain, which opens another interesting window to quantitatively measure the local strain using SERS. Our experimental study may be useful for the application of monolayer MX2 in flexible nano-optoelectronics.
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A new flow-injection catalytic spectrophotometric method was proposed for the determination of Se(IV) based on its catalytic effect on the reduction reaction of azure I by Na2S in pH 7.0 citric-acid sodium-hydrogen-phosphate buffer solution. Some different schematic diagrams of FIA were compared. Effects of the flow rates of reagents and sample, the medium and its acidity, the temperature, and coexistent substances were studied respectively. The amount of used reagents and the experimental conditions for sampling volume and coil length were optimized by using the controlled and weighed centroid simplex method. The Linear range of the determination is 0.1-2.0 mg x L(-1), the detection limit is 0.015 mg x L(-1), the relative standard deviation is less than 3.1%, and the sampling frequency is 120 samples per hour. The method has been applied to the determination of organic selenium and inorganic selenium in garlic and selenium-yeast. It was found that garlic had a strong enriching effect for selenium, and the conversion ratio of organic selenium decreased with increasing the concentration of selenium in the environment. The recovery of this method is 97.1%-104.3%.
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Selênio/análise , Espectrofotometria/métodos , Catálise , Análise de Injeção de Fluxo , Alho/química , Compostos Organometálicos/análise , Reprodutibilidade dos Testes , Selênio/química , Compostos de Selênio/análise , Espectrofotometria/instrumentação , Temperatura , Leveduras/químicaRESUMO
N-doped graphene displays many interesting properties compared with pristine graphene, which makes it a potential candidate in many applications. Here, we report that the Shubnikov-de Haas (SdH) oscillation effect in graphene can be enhanced by N-doping. We show that the amplitude of the SdH oscillation increases with N-doping and reaches around 5k Ω under a field of 14 T at 10 K for highly N-doped graphene, which is over 1 order of magnitude larger than the value found for pristine graphene devices with the same geometry. Moreover, in contrast to the well-established standard Lifshitz-Kosevich theory, the amplitude of the SdH oscillation decreases linearly with increasing temperature and persists up to a temperature of 150 K. Our results also show that the magnetoresistance (MR) in N-doped graphene increases with increasing temperature. Our results may be useful for the application of N-doped graphene in magnetic devices.
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Recently, significant attention has been paid to the resistance switching (RS) behaviour in Fe3O4 and it was explained through the analogy of the electrically driven metal-insulator transition based on the quantum tunneling theory. Here, we propose a method to experimentally support this explanation and provide a way to tune the critical switching parameter by introducing self-aligned localized impurities through the growth of Fe3O4 thin films on stepped SrTiO3 substrates. Anisotropic behavior in the RS was observed, where a lower switching voltage in the range of 10(4) V cm(-1) is required to switch Fe3O4 from a high conducting state to a low conducting state when the electrical field is applied along the steps. The anisotropic RS behavior is attributed to a high density array of anti-phase boundaries (APBs) formed at the step edges and thus are aligned along the same direction in the film which act as a train of hotspot forming conduits for resonant tunneling. Our experimental studies open an interesting window to tune the electrical-field-driven metal-insulator transition in strongly correlated systems.
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Anaplasma platys is a parasite of canine platelets that causes infectious cyclic thrombocytopenia. In this study, a novel real-time loop-mediated isothermal amplification (RT-LAMP) method was developed to detect A. platys. RT-LAMP primer sets were designed using a citrate synthase gene sequence and the assay was performed at 63 °C for 30 min. No cross-reactivity was observed with other Anaplasma or Ehrlichia spp. and the method exhibited a similar level of sensitivity in detecting the organism in 58 canine blood samples to that of a nested PCR. This RT-LAMP is a rapid and potentially cost-effective method of diagnosing A. platys infection in dogs.
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Anaplasma/isolamento & purificação , Anaplasmose/diagnóstico , Doenças do Cão/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/veterinária , Anaplasma/genética , Anaplasmose/parasitologia , Animais , China , Doenças do Cão/parasitologia , Cães , Ehrlichia/genética , Ehrlichia/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/economia , Sensibilidade e EspecificidadeRESUMO
Although the mechanism of superconductivity in the cuprates remains elusive, it is generally agreed that at the heart of the problem is the physics of doped Mott insulators. A crucial step for solving the high temperature superconductivity puzzle is to elucidate the electronic structure of the parent compound and the behaviour of doped charge carriers. Here we use scanning tunnelling microscopy to investigate the atomic-scale electronic structure of the Ca(2)CuO(2)Cl(2) parent Mott insulator of the cuprates. The full electronic spectrum across the Mott-Hubbard gap is uncovered for the first time, which reveals the particle-hole symmetric and spatially uniform Hubbard bands. Defect-induced charge carriers are found to create broad in-gap electronic states that are strongly localized in space. We show that the electronic structure of pristine Mott insulator is consistent with the Zhang-Rice singlet model, but the peculiar features of the doped electronic states require further investigations.
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A novel technique, high temperature headspace liquid-phase microextraction (HS-LPME) with room temperature ionic liquid (RTIL), 1-butyl-3-methylimidazolium hexafluorophosphate ([C4MIM][PF6]) as extractant, was developed for the analysis of dichlorodiphenyltrichloroethane (p,p'-DDT and o,p'-DDT) and its metabolites including 4,4'-dichlorodiphenyldichloroethylene (p,p'-DDE) and 4,4'-dichlorodiphenyldichloroethane (p,p'-DDD) in water samples by high performance liquid chromatography with ultraviolet detection. The parameters such as salt content, sample pH and temperature, stirring rate, extraction time, microdrop volume, and sample volume, were found to have significant influence on the HS-LPME. The conditions optimized for extraction of target compounds were as follows: 35% NaCl (w/v), neutral pH condition, 70 degrees C, 800 rpm, 30 min, 10 microL [C4MIM][PF6], and 25 mL sample solutions. Under the optimized conditions, the linear range, detection limit (S/N=3), and precision (R.S.D., n=6) were 0.3-30 microg L(-1), 0.07 microg L(-1), and 8.0% for p,p'-DDD, 0.3-30 microg L(-1), 0.08 microg L(-1), and 7.1% for p,p'-DDT, 0.3-30 microg L(-1), 0.08 microg L(-1), and 7.2% for o,p'-DDT, and 0.2-30 microg L(-1), 0.05 microg L(-1), and 6.8% for p,p'-DDE, respectively. Water samples including tap water, well water, snow water, reservoir water, and wastewater were analyzed by the proposed procedure and the recoveries at 5 microg L(-1) spiked level were in the range of 86.8-102.6%.