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1.
Nature ; 578(7796): 545-549, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32103195

RESUMO

Chirality is ubiquitous in nature, and populations of opposite chiralities are surprisingly asymmetric at fundamental levels1,2. Examples range from parity violation in the subatomic weak force to homochirality in biomolecules. The ability to achieve chirality-selective synthesis (chiral induction) is of great importance in stereochemistry, molecular biology and pharmacology2. In condensed matter physics, a crystalline electronic system is geometrically chiral when it lacks mirror planes, space-inversion centres or rotoinversion axes1. Typically, geometrical chirality is predefined by the chiral lattice structure of a material, which is fixed on formation of the crystal. By contrast, in materials with gyrotropic order3-6, electrons spontaneously organize themselves to exhibit macroscopic chirality in an originally achiral lattice. Although such order-which has been proposed as the quantum analogue of cholesteric liquid crystals-has attracted considerable interest3-15, no clear observation or manipulation of gyrotropic order has been achieved so far. Here we report the realization of optical chiral induction and the observation of a gyrotropically ordered phase in the transition-metal dichalcogenide semimetal 1T-TiSe2. We show that shining mid-infrared circularly polarized light on 1T-TiSe2 while cooling it below the critical temperature leads to the preferential formation of one chiral domain. The chirality of this state is confirmed by the measurement of an out-of-plane circular photogalvanic current, the direction of which depends on the optical induction. Although the role of domain walls requires further investigation with local probes, the methodology demonstrated here can be applied to realize and control chiral electronic phases in other quantum materials4,16.

3.
J Pediatr ; 219: 31-37.e6, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32061408

RESUMO

OBJECTIVE: To identify distinct body mass index (BMI) trajectories across the life-course and explore the effects of BMI trajectories on the adult cardiovascular disease outcomes using a dataset with 30 years of follow-up in northern China. STUDY DESIGN: A total of 2839 participants aged 6-18 years whose BMIs were measured 3-6 times during the Hanzhong Adolescent Hypertension Study were included in our analysis. Latent mixture modeling was used to clarify distinct BMI trajectories in longitudinal analyses. RESULTS: Three groups with distinct trajectories in BMI were identified by the latent mixed models: a low-increasing group (n = 1324 [36.64%]), a moderate-increasing group (n = 1178 [16.89%]), and a high-increasing group (n = 337 [39.46%]). Compared with the participants in the low-increasing group, the risk ratios of hypertension, type 2 diabetes mellitus, high-risk triglycerides, and high-risk high-density lipoprotein cholesterol were more than 3.0 in the high-increasing group (all P < .001) after being fully adjusted. Increased risks existed in high brachial-ankle pulse wave velocity for the high-increasing group compared with the low-increasing group (RR, 2.75; 95% CI, 1.94-3.91; P < .001). Additionally, participants in the moderate-increasing group had a 2.31-fold increased risks of left ventricular hypertrophy (95% CI, 1.25-4.30; P = .008). CONCLUSIONS: Our study indicates that BMI trajectories from childhood to adulthood vary and that an elevated BMI trajectory in early life is predictive of an increased the risk of developing cardiovascular disease risks. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02734472.

4.
J Sep Sci ; 43(8): 1514-1522, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31984639

RESUMO

In this study, porous sandwich structure Fe3 O4 nanoparticles coated by polyhedral oligomeric silsesquioxanes and ß-cyclodextrin were prepared by surface polymerization and were used as the magnetic solid phase extraction adsorbent for the extraction and determination of carbaryl and carbofuran. The Fe3 O4 nanoparticles coated with polyhedral oligomeric silsesquioxanes and ß-cyclodextrin were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, and scanning electron microscopy. After optimizing the extraction conditions, a method that combined magnetic solid phase extraction with high-performance liquid chromatography was developed for the determination of carbaryl and carbofuran in apple. The method exhibited a good linearity in the range of 2-400 µg/kg for carbaryl and carbofuran (R2  = 0.9995), respectively. The limits of detection were 0.5 µg/kg of carbaryl and 0.7 µg/kg for carbofuran in apple, respectively. Extraction recoveries ranged from 94.2 to 103.1% with the preconcentration factor of 300 and the relative standard deviations were less than 5.9%. These results indicated that the method combined magnetic solid phase extraction with high-performance liquid chromatography and was promising for the determination of carbaryl and carbofuran at trace amounts.

5.
Eur J Clin Nutr ; 74(2): 278-284, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31728032

RESUMO

BACKGROUND: A high atherogenic index of plasma (AIP) is associated with increased cardiovascular risk and higher serum uric acid levels, but whether AIP is a strong risk factor for developing subclinical renal damage (SRD) is unknown. This study aimed to explore the effect of AIP variations on the prevalence of SRD in a 12-year follow-up study. METHODS: (1) The cross-sectional study enrolled 2485 participants from the Hanzhong cohort in 2017; (2) A total of 202 participants were included in the small longitudinal cohort from 2005 to 2017. Longitudinal analysis was used to determine whether an elevated AIP predicts the development of SRD. RESULTS: In the cross-sectional analysis, the AIP level was correlated with the estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatine ratio (uACR) (P < 0.05). The age-adjusted odds ratio (OR) for prevalent SRD in men in the high AIP group was 1.924 (1.355-2.732) (P < 0.001), while in women, the OR was 1.616 (1.049-2.490) (P = 0.030) in the high AIP group. In the longitudinal analysis, significantly higher uACR levels were found in participants with normal AIP at baseline and elevated AIP in 2013 (P < 0.05). The adjusted OR for prevalent SRD in the incident AIP group was 4.741 (1.668-13.472) (P = 0.003) compared with the control group. CONCLUSIONS: Our study indicates that elevated AIP increased the risk of developing SRD and was associated with uACR and eGFR. As a simple marker of CVD risk, AIP may emerge as a novel and reliable indicator of SRD.

6.
Langmuir ; 35(49): 16071-16078, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31743031

RESUMO

In this work, adsorption behaviors of pyrene (PYR), fluoranthene (FLT), phenanthrene (PHE), and fluorene (FLU) on the coordination cluster [Zn5(H2Ln)6](NO3)4]·8H2O·2CH3OH (Zn5) were studied. The adsorption mechanism and spectrum analyses revealed that the synergistic effect of hydrophobic interaction, π-π stacking, and N-H···π interaction played a crucial role during the adsorption process. The maximum adsorption capacities of PYR, FLT, PHE, and FLU were 406.4, 399.7, 153.7, and 114.3 mg g-1, respectively, resulting from the Langmuir isotherm model. Quick removal of PYR and FLT was found in kinetic experiments with the adsorption equilibrium being reached within 1 min. Competitive adsorption indicated that the adsorption sites for PYR, FLT, PHE, and FLU on Zn5 were identical, and synergistic effects also existed in the adsorption process. Therefore, Zn5 has the potential to be used as an adsorbent in the field of wastewater treatment.

7.
PLoS One ; 14(11): e0224680, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31730636

RESUMO

BACKGROUND AND OBJECTIVES: The aim of the study was to examine the associations of uric acid (UA) in blood and urine with subclinical renal damage (SRD) and its progression in a Chinese cohort. METHODS: 1) 2342 participants from our previously established cohort who were followed up in 2017 were included. Cross-sectional analysis was used to examine the relationships between serum and urinary UA and the risk of SRD. 2) A total of 266 participants were recruited from the same cohort in 2013, and followed up in 2017. Longitudinal analysis was used to determine the relationships of serum and urinary UA with progression of SRD, which was defined as urinary albumin-to-creatinine ratio (uACR) progression or estimated glomerular filtration rate (eGFR) decline. RESULTS: In cross-sectional analysis, higher levels of uACR were associated with higher levels of serum uric acid (SUA) and urinary uric acid/creatinine ratio (uUA/Cre). Lower eGFR was associated with higher levels of SUA and fractional excretion of uric acid (FEUA) but lower uUA/Cre levels in all subjects. In addition, the multivariate-adjusted odds ratios for SRD compared with non-SRD were 3.574 (2.255-5.664) for uUA/Cre. Increasing uUA/Cre levels were associated with higher risk of SRD. In longitudinal analysis, 4-year changes of uUA/Cre and SUA were significantly associated with eGFR decline. CONCLUSIONS: This study suggested that urinary UA excretion was significantly associated with the risk of SRD in Chinese adults. Furthermore, 4-year changes of serum and urinary UA were associated with SRD progression. These findings suggest that UA, especially urinary UA, may be used as a simple, noninvasive marker for early detection of decreased renal function in otherwise healthy subjects.

8.
Cell Death Dis ; 10(8): 575, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366916

RESUMO

Most circulating tumor cells (CTCs) die during the process of metastasis, but self-seeding CTCs can invade the primary tumor or form clinically meaningful metastases. This study aimed to evaluate the capacity of self-seeding CTCs to promote osteosarcoma growth and lung metastasis and to clarify the specific role of interleukin (IL)-8 in CTC self-seeding. We successfully isolated and cultured self-seeding CTCs through a self-seeding nude mouse model established using green fluorescent protein (GFP)-labeled F5M2 cells and found that self-seeding CTCs exhibit increased cellular proliferation, migration, and invasion in vitro, increased tumor growth and lung metastasis in mice, and increased IL-8 expression. Furthermore, suppressing IL-8 inhibited tumor growth and metastasis and reduced CTC seeding in primary tumors in vitro and in vivo. In osteosarcoma patients, IL-8 levels significantly correlated with the Enneking stage and metastasis. These findings demonstrate that self-seeding osteosarcoma CTCs can promote tumor growth and lung metastasis through IL-8. Their increased metastatic potential and elevated IL-8 expression suggest a novel strategy for future therapeutic interventions to prevent osteosarcoma progression and metastasis.

9.
Emerg Microbes Infect ; 8(1): 1223-1228, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31429668

RESUMO

Here, we report the first imported case of melioidosis from Laos in central China. COMPACT VITEK2 identification system and PCR, as well as sequencing methods confirmed that the patient was infected by Burkholderia pseudomallei, a bacterial species closely related to an isolate detected in Thailand. These findings are highly valuable for an early diagnosis, treatment and to prevent the spread of this emerging infectious disease in central China.


Assuntos
Burkholderia pseudomallei/isolamento & purificação , Melioidose/diagnóstico , Melioidose/patologia , Técnicas de Tipagem Bacteriana , China , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
10.
Cardiology ; 144(1-2): 27-35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31434092

RESUMO

BACKGROUND: Elevated plasma homocysteine (Hcy) and high-sensitivity C-reactive protein (hsCRP) levels are independent risk factors for cardiovascular diseases. However, it is unclear whether the coexistence of these conditions accelerates the risk of arterial stiffness. Our study aimed to evaluate the association of combined Hcy and hsCRP with arterial stiffness in Chinese middle-aged adults. MATERIAL/METHODS: We conducted a 12-year longitudinal study in 220 individuals in Hanzhong, China, from 2005 to 2017. The average age at follow-up was 41.83 ± 3.10 years. Demographic information, medical history, anthropometric measurements, and blood pressure as well as urine and fasting blood samples, including Hcy, hsCRP, and brachial-ankle pulse wave velocity (baPWV) were measured and analyzed. RESULTS: BaPWV levels showed a linear growth trend with the increasing of hsCRP (p for trend <0.01). The ORs in the highest quartile compared to the lowest quartile were 1.985 (95% CI 0.776-5.077; p = 0.152) and 3.960 (95% CI 1.468-10.684; p= 0.007) for Hcy and hsCRP, respectively. When Hcy and hsCRP were combined, subjects in both the highest quartile of Hcy and hsCRP (Hcy ≥15.50 µmol/L and hsCRP ≥0.82 µmol/L) had a 12.68-fold increased risk of developing arterial stiffness at the 12-year follow-up compared to those in the lowest quartile of Hcy and hsCRP (Hcy ≤9.91 µmol/L and hsCRP ≤0.19 µmol/L) after adjusting for potential confounders. CONCLUSIONS: The present study demonstrated that the combination of elevated serum Hcy and hsCRP may contribute to an increased risk of arterial stiffness.

11.
Adv Mater ; 31(37): e1806603, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31353629

RESUMO

Phonon polaritons in van der Waals materials reveal significant confinement accompanied with long propagation length: important virtues for tasks pertaining to the control of light and energy flow at the nanoscale. While previous studies of phonon polaritons have relied on relatively thick samples, here reported is the first observation of surface phonon polaritons in single atomic layers and bilayers of hexagonal boron nitride (hBN). Using antenna-based near-field microscopy, propagating surface phonon polaritons in mono- and bilayer hBN microcrystals are imaged. Phonon polaritons in monolayer hBN are confined in a volume about one million times smaller than the free-space photons. Both the polariton dispersion and their wavelength-thickness scaling law are altered compared to those of hBN bulk counterparts. These changes are attributed to phonon hardening in monolayer-thick crystals. The data reported here have bearing on applications of polaritons in metasurfaces and ultrathin optical elements.

12.
Org Lett ; 21(12): 4812-4815, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31192612

RESUMO

A novel ruthenium-catalyzed [5 + 1] annulation of 2-alkenylanilines with sulfoxonium ylides was developed for the rapid assembly of highly functionalized quinolines. This new catalytic process employs challenging but synthetically ideal free amino functionality to achieve alkenyl C-H activation with sulfoxonium ylides as one-carbon coupling partners. Various 2-acylquinolines could be obtained with good yields and excellent functional group tolerance. Moreover, the potential synthetic application of this methodology was exemplified by several chemical transformations.

13.
Proc Natl Acad Sci U S A ; 116(27): 13255-13259, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31196954

RESUMO

Bismuth-based materials have been instrumental in the development of topological physics, even though bulk bismuth itself has been long thought to be topologically trivial. A recent study has, however, shown that bismuth is in fact a higher-order topological insulator featuring one-dimensional (1D) topological hinge states protected by threefold rotational and inversion symmetries. In this paper, we uncover another hidden facet of the band topology of bismuth by showing that bismuth is also a first-order topological crystalline insulator protected by a twofold rotational symmetry. As a result, its [Formula: see text] surface exhibits a pair of gapless Dirac surface states. Remarkably, these surface Dirac cones are "unpinned" in the sense that they are not restricted to locate at specific k points in the [Formula: see text] surface Brillouin zone. These unpinned 2D Dirac surface states could be probed directly via various spectroscopic techniques. Our analysis also reveals the presence of a distinct, previously uncharacterized set of 1D topological hinge states protected by the twofold rotational symmetry. Our study thus provides a comprehensive understanding of the topological band structure of bismuth.

14.
Sci Adv ; 5(6): eaav1493, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31214647

RESUMO

The massless Dirac electron transport in graphene has led to a variety of unique light-matter interaction phenomena, which promise many novel optoelectronic applications. Most of the effects are only accessible by breaking the spatial symmetry, through introducing edges, p-n junctions, or heterogeneous interfaces. The recent development of direct synthesis of lateral heterostructures offers new opportunities to achieve the desired asymmetry. As a proof of concept, we study the photothermoelectric effect in an asymmetric lateral heterojunction between the Dirac semimetallic monolayer graphene and the parabolic semiconducting monolayer MoS2. Very different hot-carrier cooling mechanisms on the graphene and the MoS2 sides allow us to resolve the asymmetric thermalization pathways of photoinduced hot carriers spatially with electrostatic gate tunability. We also demonstrate the potential of graphene-2D semiconductor lateral heterojunctions as broadband infrared photodetectors. The proposed structure shows an extreme in-plane asymmetry and provides a new platform to study light-matter interactions in low-dimensional systems.

15.
Mol Med Rep ; 20(1): 292-302, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31115575

RESUMO

Increasing amounts of long noncoding RNAs (lncRNAs) have been shown to be involved in the development of cancer. Recently, aberrant expression of the lncRNA forkhead box D2 adjacent opposite strand RNA1 (FOXD2­AS1) has been reported to be involved in the progression of several types of human cancer. However, the function and mechanism of FOXD2­AS1 in osteosarcoma (OS) are currently unclear. The present study aimed to investigate the function and mechanism of FOXD2­AS1 in OS. Firstly, it was revealed that the expression levels of FOXD2­AS1 were significantly upregulated in OS tissues and cells, compared with in adjacent tissues and normal cells, as determined using reverse transcription­quantitative polymerase chain reaction. Notably, the overall survival of patients with relatively high FOXD2­AS1 expression in OS tissues was significantly lower than that of patients with relatively low expression, as determined using Kaplan­Meier analysis. In addition, loss­of­function experiments were performed in vivo and in vitro to study the biological effects of FOXD2­AS1. The SOSP­9607 and U2OS OS cell lines were infected with lentivirus­mediated FOXD2­AS1 short hairpin RNA; subsequently, the alterations in cell phenotype and downstream molecules were evaluated. Knockdown of FOXD2­AS1 inhibited the proliferation, migration and invasion of OS cells. Furthermore, the number of cells in the S phase was significantly decreased, which was consistent with the results of the Cell Counting kit 8 proliferation assay. The expression levels of ribonucleotide reductase regulatory subunit M2 and phosphoglycerate dehydrogenase were decreased, as determined by western blotting, following FOXD2­AS1 knockdown. Finally, in a nude mouse model of tumorigenesis, it was revealed that, when FOXD2­AS1 expression was downregulated, tumor growth was significantly reduced and pulmonary metastatic nodules were markedly reduced. The results of the present study suggested that decreased FOXD2­AS1 expression may inhibit the growth, migration and invasion of tumor cells, and it may regulate downstream gene expression. In conclusion, these findings indicated that FOXD2­AS1 may be used as a potential therapeutic target and early tumor marker for the diagnosis and prognosis of OS.


Assuntos
Carcinogênese/genética , Proliferação de Células/genética , Osteossarcoma/genética , RNA Longo não Codificante/genética , Adolescente , Adulto , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Criança , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Osteossarcoma/patologia , Prognóstico , Adulto Jovem
16.
J Hypertens ; 37(6): 1167-1175, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31026243

RESUMO

OBJECTIVE: Atherosclerotic diseases are the leading cause of death worldwide. This study aimed to investigate the predictors of brachial-ankle pulse wave velocity (baPWV) and carotid intima-media thickness (CIMT) progression in a Chinese cohort over a 12-year follow-up period and to determine whether these predictors differ by follow-up time. METHODS: A total of 202 participants were recruited from a previously established cohort in Shaanxi Province, China. Both baPWV and CIMT were measured in 2013 and 2017. Multivariable regression was used to determine the predictors of CIMT and baPWV progression. RESULTS: Men had higher CIMT and baPWV and a higher rate of CIMT progression during two follow-ups than women. A 4-year change in SBP was associated with baPWV progression, whereas a 12-year change in DBP was associated with baPWV progression. The increased progression of baPWV presented a linear trend when subgrouping all the participants according to SBP and DBP changes over 4 and 12 years, respectively. In addition, heart rate (HR) change over 4 and 12 years was consistently associated with CIMT progression, and a linear trend was also seen when subgrouping the population. CONCLUSION: Our study demonstrated that SBP and DBP contributed differently in different stages to the progression of arterial stiffness in this Chinese cohort. Moreover, HR was consistently involved in the increased progression of CIMT in all periods. These findings underline the importance of early detection and control of blood pressure and resting HR for the prevention of arterial stiffness progression.

17.
Adv Mater ; 31(18): e1900251, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30907483

RESUMO

Unlike conventional plasmonic media, polaritonic van der Waals (vdW) materials hold promise for active control of light-matter interactions. The dispersion relations of elementary excitations such as phonons and plasmons can be tuned in layered vdW systems via stacking using functional substrates. In this work, infrared nanoimaging and nanospectroscopy of hyperbolic phonon polaritons are demonstrated in a novel vdW heterostructure combining hexagonal boron nitride (hBN) and vanadium dioxide (VO2 ). It is observed that the insulator-to-metal transition in VO2 has a profound impact on the polaritons in the proximal hBN layer. In effect, the real-space propagation of hyperbolic polaritons and their spectroscopic resonances can be actively controlled by temperature. This tunability originates from the effective change in local dielectric properties of the VO2 sublayer in the course of the temperature-tuned insulator-to-metal phase transition. The high susceptibility of polaritons to electronic phase transitions opens new possibilities for applications of vdW materials in combination with strongly correlated quantum materials.

18.
J Clin Nurs ; 28(7-8): 1148-1155, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30375697

RESUMO

AIM AND OBJECTIVE: To investigate the incidence of intraoperative blanchable erythema and pressure injuries in patients undergoing digestive surgery and to explore potential risk factors. BACKGROUND: Pressure injuries pose significant economic and healthcare burden to patients and are used as one of the key indicators of nursing in the operation room with high incidence. DESIGN: A retrospective observational study. METHODS: Basic information and the results of 3S intraoperative risk assessment scale of pressure injury were obtained from the information system. And the patients with intraoperative blanchable erythema or pressure injuries were followed up for 72 hr by the information system. The clinical data were collected to analyse risk factors for intraoperative blanchable erythema and pressure injuries by univariate analysis and logistic regression analysis. STROBE checklist for cohort studies was applied in the preparation of the paper. RESULTS: Of 5,136 surgical cases, 134 (2.61%) had blanchable erythema, 37 (0.72%) had intraoperative pressure injuries, and 8 (0.16%) had pressure injuries at 72-hr follow-up. Preoperative skin under compression, preoperative physical activity, surgical position and extra intraoperative pressure were considered independent risk factors for intraoperative pressure injuries. CONCLUSION: The incidence of pressure injuries in our study was lower than those reported in the previous studies. Accessing preoperative skin under compression, preoperative physical activity, surgical position and extra intraoperative pressure was considered to be significant for preventing pressure injuries. RELEVANCE TO CLINICAL PRACTICE: The findings suggest that preoperative skin under compression, preoperative physical activity, surgical position and extra intraoperative pressure are associated with intraoperative pressure injuries in patients undergoing digestive surgery.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Eritema/epidemiologia , Cuidados Pré-Operatórios/enfermagem , Lesão por Pressão/epidemiologia , Adulto , Idoso , Comorbidade , Eritema/prevenção & controle , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Posicionamento do Paciente/métodos , Lesão por Pressão/prevenção & controle , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
19.
Biochem Biophys Res Commun ; 508(3): 877-881, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30538044

RESUMO

A growing number of studies suggest that synovitis plays an important role in the pathogenesis and progression of osteoarthritis (OA). As a negative mediator of the nuclear factor-kappa B (NF-κB) signaling pathway, the zinc finger protein A20 has significant anti-inflammatory properties. In this study, the differential expression of A20 was investigated at the mRNA and protein levels in human normal OA fibroblast-like synoviocytes (FLSs) and normal FLSs pretreated with TNF-α. We then measured the activation of the NF-κB pathway and expression of pro-inflammatory cytokines in the above three groups by western blotting, a human cytokine array and ELISA. We found that TNF-α activated the NF-κB pathway, increased the expression of the pro-inflammatory cytokines IL-6 and IL-8, and A20 expression in human normal FLSs. However, the role of A20 in FLSs was unclear. To clarify this, we investigated the effect of A20 overexpression in human normal FLSs. The results indicate that A20 inhibits the NF-κB signaling pathway activation and OA-associated pro-inflammatory cytokines release. The results of this study indicate that A20 has anti-inflammatory effects in FLSs, which makes it a potential target for OA synovitis treatment.


Assuntos
Citocinas/metabolismo , NF-kappa B/metabolismo , Osteoartrite do Joelho/metabolismo , Sinoviócitos/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/fisiologia , Células Cultivadas , Fibroblastos/citologia , Humanos , Mediadores da Inflamação/metabolismo , Osteoartrite do Joelho/genética , Sinoviócitos/efeitos dos fármacos , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
20.
Nature ; 565(7739): 337-342, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30559379

RESUMO

The electrical Hall effect is the production, upon the application of an electric field, of a transverse voltage under an out-of-plane magnetic field. Studies of the Hall effect have led to important breakthroughs, including the discoveries of Berry curvature and topological Chern invariants1,2. The internal magnetization of magnets means that the electrical Hall effect can occur in the absence of an external magnetic field2; this 'anomalous' Hall effect is important for the study of quantum magnets2-7. The electrical Hall effect has rarely been studied in non-magnetic materials without external magnetic fields, owing to the constraint of time-reversal symmetry. However, only in the linear response regime-when the Hall voltage is linearly proportional to the external electric field-does the Hall effect identically vanish as a result of time-reversal symmetry; the Hall effect in the nonlinear response regime is not subject to such symmetry constraints8-10. Here we report observations of the nonlinear Hall effect10 in electrical transport in bilayers of the non-magnetic quantum material WTe2 under time-reversal-symmetric conditions. We show that an electric current in bilayer WTe2 leads to a nonlinear Hall voltage in the absence of a magnetic field. The properties of this nonlinear Hall effect are distinct from those of the anomalous Hall effect in metals: the nonlinear Hall effect results in a quadratic, rather than linear, current-voltage characteristic and, in contrast to the anomalous Hall effect, the nonlinear Hall effect results in a much larger transverse than longitudinal voltage response, leading to a nonlinear Hall angle (the angle between the total voltage response and the applied electric field) of nearly 90 degrees. We further show that the nonlinear Hall effect provides a direct measure of the dipole moment10 of the Berry curvature, which arises from layer-polarized Dirac fermions in bilayer WTe2. Our results demonstrate a new type of Hall effect and provide a way of detecting Berry curvature in non-magnetic quantum materials.

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