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1.
Sci Total Environ ; : 134771, 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31784165

RESUMO

China's Mu Us Desert, located in an energy-rich strategic base of the northwestern Loess Plateau, has acted as a crucial agro-pastoral transition zone for thousands of years. However, the area experienced notable climate and environmental change from 221 BCE to CE 907 (1128 years), which may have profoundly affected its landscape evolution up to modern times. To explore this process and associated driving mechanisms, we conducted a comprehensive study based on a dataset of 882 human archaeological sites (HASs), historical documents, and related environmental data of the Mu Us Desert and its surrounding area (MUDISA). We found that the MUDISA experienced large-scale immigration and an agricultural boom (790 HASs) during the Qin and Han dynasties (221 BCE-CE 220). This coincided with an ecologically favorable environment and may have potentially disturbed the desert's eco-environmental equilibrium. Coinciding with the deteriorating natural conditions, the MUDISA's animal husbandry replaced agriculture as the dominant subsistence economy during the era of disunity (CE 220-581, 33 HASs) and during the Sui and Tang dynasties (CE 581-907, 59 HASs). Although natural and political-economic factors together caused a sharp decline in number and scattering for HASs in the desert, people and livestock were widely distributed and maintained a high population level. This situation, coupled with the dry climate and fragile geographical environment, may have significantly accelerated the climate-driven desertification process from CE 220 to CE 907. This study highlights the long-term human-nature relationship and its impact on historical desertification in the Mu Us Desert, and may shed new light on historical environmental change in arid and/or semi-arid areas in northwest China and globally.

2.
Autoimmunity ; : 1-7, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31790283

RESUMO

High mobility group box 1 (HMGB1) played pathogenic role in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Recent findings demonstrated that Toll-like receptor 9 (TLR9) was involved in B cell tolerance breaking of autoimmune disease, including AAV. Here, we investigated the effect of HMGB1 on TLR9 in B cells of AAV. In the present work, patients with myeloperoxidase (MPO)-AAV in active stage were recruited. Intracellular TLR9 expression in various B cell subpopulations of the whole blood was detected by flow cytometry and the correlation with clinical data was analysed. Our results showed that intracellular TLR9 expression in B cells, memory B cells and plasmablasts correlated with erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP). In particular, TLR9 expression in plasma cells correlated with ESR, CRP, serum creatinine, eGFR, and Birmingham Vasculitis Activity Score. To further explore the effect of HMGB1 on B cell, peripheral blood mononuclear cells (PBMCs) from AAV patients were isolated. After stimulated with HMGB1, TLR9 expression in various B cell subpopulations and proliferation ratio of live B cells were analysed by flow cytometry. We found that TLR9 expression in plasma cells and the proliferation ratio of live B cells by HMGB1 stimulation were significantly upregulated compared with the control group. Therefore, TLR9 expression in plasma cells was associated with disease activity of MPO-AAV. HMGB1 could enhance TLR9 expression in plasma cells and B cell proliferation. These indicated a role of HMGB1 on TLR9 in B cells in MPO-AAV, which would provide potential clues for intervention strategies.

3.
BMC Med Genet ; 20(1): 168, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666013

RESUMO

BACKGROUND: Myasthenia gravis (MG) is an autoimmune diseases characterized by fatigue and weakness of skeletal muscles. B-lymphocyte-activating factor (BAFF), an essential factor for B cell differentiation and development, is important in the progression of MG. The current study aimed to investigate the association between single nucleotide polymorphism rs2893321 in BAFF with MG susceptibility in Chinese Han population. METHODS: One hundred forty-nine patients with MG and 148 healthy controls were recruited. Using improved multiple ligase detection reaction technology, the polymorphisms of rs2893321 between groups and among MG subgroups have been compared. RESULTS: A significant differences between the MG group and the healthy control group was observed. Additionally, rs2893321 was found to be associated with gender and age in patients with MG. CONCLUSION: Genetic variations of rs2893321 in BAFF might be associated with susceptibility to MG in the Chinese Han population.

4.
Microbiol Res ; 231: 126369, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31733598

RESUMO

The ability of endophytic fungi isolated from cucurbit plants to suppress soilborne diseases and the relationship between antagonism and disease suppression were studied. In dual culture tests of 1044 strains of 90 genera and three pathogenic fungi, 47.1 % of the endophytic fungal strains showed antagonistic effects on at least one pathogen; 186 strains against Rhizoctonia solani, 371 strains against Sclerotinia sclerotiorum, and 403 strains against Fusarium oxysporum f. sp. cucumerinum. The main antagonistic type of the strains of one genus generally was identical to one pathogen. In the pot experiment of cucumber inoculated with R. solani and endophytic fungi, 74.3 % and 33.3 % of 288 strains showed control efficacy of more than 50 % and more than 80 % on cucumber Rhizoctonia root rot respectively. These strains were mostly distributed in Fusarium, Chaetomium, Colletotrichum and Acrocalymma. There were some differences in the proportion of strains with better disease suppressive effects between strain sources. No significant correlation existed between the disease suppression of a strain in vivo and its antagonism against the pathogen in vitro. Most growth-promoting strains had good suppressive effects on cucumber Rhizoctonia root rot. In this study, 82 endophytic fungal strains had good disease suppressive effects and no obvious adverse effects on cucumber growth, and 35 of them showed obvious growth-promoting effects, which suggested that endophytic fungi from cucurbit plants have excellent potential for plant disease control.

5.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(11): 1144-1147, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31753099

RESUMO

Adverse environmental stimulation in the neonatal intensive care unit (NICU) can affect neurodevelopment through epigenetic modification and thus has adverse effects on the long-term developmental outcome of preterm infants. Developmental care can reverse epigenetic changes in genes and promote neurodevelopment in preterm infants. This article reviews the influence of environmental stress in the NICU and developmental care on neurodevelopment in preterm infants, as well as related epigenetic effects, in order to provide a reference for epigenetic studies of preterm infants.


Assuntos
Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Epigênese Genética , Humanos , Lactente , Recém-Nascido
6.
Analyst ; 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31777868

RESUMO

This work demonstrates a novel chemosensor, SPTPA, that exhibits fluorescence and colorimetric dual sensing of hypochlorite with an ICT ON strategy. Additionally, the chemosensor successfully detected and imaged endogenous hypochlorite in living cells, various types of bacteria, and zebrafish.

7.
Stem Cell Res ; 41: 101661, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31759290

RESUMO

Peripheral blood mononuclear cells (PBMCs) were collected from a 6-year-old female child who was clinically diagnosed as primary nephrotic syndrome (NS) with hormone resistance. An iPSC line was successfully established by the Sendai-virus (SeV) delivery system. The iPS-19 (GSPHi001-A) expressed pluripotent markers, exhibited a normal karyotype and differentiated towards three germ layers. The iPSC line might offer a potentially useful tool for investigating mechanisms of primary NS, drug testing and gene therapy studies.

8.
Nature ; 576(7785): 80-84, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31768043

RESUMO

Two-dimensional semiconductors have emerged as a new class of materials for nanophotonics owing to their strong exciton-photon interaction1,2 and their ability to be engineered and integrated into devices3. Here we take advantage of these properties to engineer an efficient lasing medium based on direct-bandgap interlayer excitons in rotationally aligned atomically thin heterostructures4. Lasing is measured from a transition-metal dichalcogenide heterobilayer (WSe2-MoSe2) integrated in a silicon nitride grating resonator. An abrupt increase in the spatial coherence of the emission is observed across the lasing threshold. The work establishes interlayer excitons in two-dimensional heterostructures as a gain medium with spatially coherent lasing emission and potential for heterogeneous integration. With electrically tunable exciton-photon interaction strengths5 and long-range dipolar interactions, these interlayer excitons are promising for application as low-power, ultrafast lasers and modulators and for the study of many-body quantum phenomena6.

9.
J Med Virol ; 2019 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-31587312

RESUMO

Coxsackievirus A16 (CA16) remains the most common causative agent of hand, foot, and mouth disease (HFMD), and is related to high incidence and critical complications. Vitamin D receptor (VDR) activity might affect the outcome of CA16 infection. Our case-control research aims to evaluate the relationship between VDR polymorphisms in the gene encoding and susceptibility to and severity of HFMD due to CA16. Three single-nucleotide polymorphisms (SNPs) of VDR gene were selected according to functional prediction and linkage disequilibrium, and were examined utilizing the SNPscan method to identify possible associations with HFMD caused by CA16. A significant relationship was found in the HFMD cases of polymorphism rs11574129 (GA vs GG: odds ratio (OR) = 0.068, 95% confidence interval (CI) = 0.007-0.693, P = .023; GA + AA vs GG: OR = 0.322, 95%CI = 0.106-0.984, P = .047), and vitamin D levels in genotype AA were significantly higher than those in genotype GG (P < .05). These results suggest that VDR rs11574129 may influence genetic susceptibility to CA16-associated HFMD.

10.
ACS Chem Neurosci ; 10(11): 4545-4557, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31491086

RESUMO

The supplementation of exogenous antioxidants to scavenge excessive reactive oxygen species (ROS) is an effective treatment for cerebral ischemia-reperfusion injury (CIRI) in stroke. Piperlongumine (PL), a natural alkaloid, has a great potential as a neuroprotective agent, but it also has obvious toxicity. Moreover, its neuroprotective effects remain to be improved. In this study, we designed a series of novel PL analogs by hybridizing the screened low-toxicity diketene skeleton with antioxidant effect and the 3,4,5-trimethoxyphenyl group, which may increase the antioxidant activity of PL. The intermediate was synthesized by a novel green synthesis method, and 34 compounds were obtained. The compounds without obvious cytotoxicity have remarkable antioxidant effects, especially compared with diketene skeletons and PL. The cytoprotection of the active compound decreased significantly by reduction of the carbon-carbon double bonds of the Michael acceptor in the diketene skeleton. More importantly, further study revealed that compound A9, which has the best activity, can confer protection for cells against oxidative stress and attenuate brain injury in vivo. Overall, this study provided a promising drug candidate for the treatment of CIRI and guided the further development of drug research in oxidative stress-mediated diseases.

11.
Opt Express ; 27(16): 22700-22707, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510556

RESUMO

The design of photonic structures plays a crucial role in the engineering of light-matter interactions. Planar microcavities have been widely used to establish strong light-matter coupling in semiconductor quantum wells, leading to intense research on exciton-polariton systems in the past few decades. However, planar cavities are limited in material compatibility, inflexible for mode engineering, and bulky for integration. Here we demonstrate dielectric slab photonic crystals as a flexible and compact platform for polaritons, where excitons are strongly coupled to photons confined in the leaky modes of the slab. We show our structure is well-suited for van der Waals materials, features unusual adjustable dispersions, and allows for multi-wavelength operation on a single chip.

12.
Cell Metab ; 30(4): 706-719.e6, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31495688

RESUMO

The physiological role of leptin is thought to be a driving force to reduce food intake and increase energy expenditure. However, leptin therapies in the clinic have failed to effectively treat obesity, predominantly due to a phenomenon referred to as leptin resistance. The mechanisms linking obesity and the associated leptin resistance remain largely unclear. With various mouse models and a leptin neutralizing antibody, we demonstrated that hyperleptinemia is a driving force for metabolic disorders. A partial reduction of plasma leptin levels in the context of obesity restores hypothalamic leptin sensitivity and effectively reduces weight gain and enhances insulin sensitivity. These results highlight that a partial reduction in plasma leptin levels leads to improved leptin sensitivity, while pointing to a new avenue for therapeutic interventions in the treatment of obesity and its associated comorbidities.

13.
Chem Biol Interact ; 313: 108820, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518571

RESUMO

Natural products with potent activity and less toxicity provide major sources for development of novel anti-cancer drugs. Herein, we evaluated the effects and the underlying mechanisms of a novel piperlongumine (PL) analogue L50377 on non-small-cell lung cancer (NSCLC) cells. The results revealed that L50377 displayed greater potentials of suppressing cell growth than PL. In addition, L50377 promoted cell apoptosis and pyroptosis via stimulating reactive oxygen species (ROS) generation in NSCLC cells. More interestingly, ROS mediated NF-κB suppression might be implicated in the mechanisms of L50377-induced pyroptosis in NSCLC cells. Taken together, our results suggested that L50377 served as a novel chemical agent might have great potentials for NSCLC treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Dioxolanos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Piroptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Dioxolanos/química , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo
14.
Arch Oral Biol ; 108: 104525, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31472278

RESUMO

OBJECTIVES: This study aims to investigate the role of Cannabinoid receptor 2 (CB2) on osteogenesis of bone marrow-derived mesenchymal stem cells (BMSCs) under hypoxia. MATERIALS AND METHODS: BMSCs were isolated from Sprague-Dawley rats and cultured in the presence of cobalt chloride (CoCl2) to induce intracellular hypoxia. Cell proliferation was measured with MTT assay. Quantitative real-time PCR and western blot were applied to evaluate the mRNA and protein expressions of CB2 and osteogenic indicators including osteocalcin, RUNX2, collagen-1 and osterix (SP7). The osteogenic differentiation of BMSCs was further examined by ALP assay and alizarin red S (ARS) staining. Moreover, the activation of MAPKs signaling pathways was analyzed by western blot. RESULTS: CoCl2 dose-dependently increased hypoxia inducible factor while higher concentrations (200 and 400 µM) of CoCl2 markedly inhibited cell proliferation. CoCl2 induced hypoxia significantly increased the protein and mRNA expressions of osteocalcin, RUNX2, collagen-1 and osterix, along with enhanced ALP and ARS staining. Interestingly, such effects can be inhibited by the addition of CB2 inhibitor AM630. Moreover, AM630 partially inhibited hypoxia-induced p38 and ERK pathways, which may lead to a decrease in the osteogenic transcripts of RUNX2, collagen-1 and osterix. CONCLUSIONS: CoCl2 induced hypoxia could promote osteogenesis of rat BMSCs possibly through CB2.

15.
J Periodontal Res ; 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539181

RESUMO

BACKGROUND AND OBJECTIVE: Bone remodeling during orthodontic treatment is achieved by the osteogenesis of human periodontal ligament cells (PDLCs) subjected to mechanical loadings. Transcriptional co-activator with PDZ-binding motif (TAZ) mediates bone remodeling in response to extracellular mechanical signals. This study aims to investigate the role of TAZ in osteogenesis of PDLCs under tensile strain. MATERIALS AND METHODS: A uniaxial cyclic tensile stress (CTS) at 12% elongation and 6 cycles/min (5 s on and 5 s off) was applied to PDLCs. The osteogenic differentiation was determined by the protein and gene expressions of osteogenic markers using qRT-PCR and Western blot, respectively, and further by alkaline phosphatase (ALP) activity and Alizarin Red S staining. The interaction of TAZ with core-binding factor α1 (Cbfα1) was examined by co-immunoprecipitation. The immunofluorescence histochemistry was used to examine the nucleus aggregation of TAZ and the reorganization of actin filaments. Moreover, small interfering RNA-targeting TAZ (TAZsiRNA) was used for TAZ inhibition and Y-27632 was employed for Ras homologue-associated coiled-coil protein kinase (ROCK) signaling blockage. RESULTS: CTS clearly stimulated the nucleus accumulation of TAZ and its interaction with Cbfα1. CTS-induced osteogenesis in PDLCs was significantly abrogated by the infection with TAZsiRNA, as shown by the decreased stained nodules and protein expressions of Cbfα1, collagen type I, osterix, and osteocalcin, along with the inhibition of ß-catenin signaling. Moreover, ROCK inhibition by Y-27632 hindered TAZ nucleus aggregation and its binding with Cbfα1, which subsequently lead to the decreased osteoblastic differentiation of PDLCs. CONCLUSIONS: Taken together, we propose that TAZ nucleus localization and its interaction with Cbfα1 are essential for the CTS-induced osteogenic differentiation in PDLCs. And such TAZ activation by CTS could be mediated by ROCK signaling, indicating the pivot role of ROCK-TAZ pathway for PDLCs differentiation.

16.
Phys Rev Lett ; 123(6): 060502, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31491139

RESUMO

Entanglement swapping, the process to entangle two particles without coupling them in any way, is one of the most striking manifestations of the quantum-mechanical nonlocal characteristic. Besides fundamental interest, this process has applications in complex entanglement manipulation and quantum communication. Here we report a high-fidelity, unconditional entanglement swapping experiment in a superconducting circuit. The measured concurrence characterizing the qubit-qubit entanglement produced by swapping is above 0.75, confirming most of the entanglement of one qubit with its partner is deterministically transferred to another qubit that has never interacted with it. We further realize delayed-choice entanglement swapping, showing whether two qubits previously behaved as in an entangled state or as in a separable state is determined by a later choice of the type of measurement on their partners. This is the first demonstration of entanglement-separability duality in a deterministic way.

17.
Phys Rev Lett ; 123(5): 050502, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31491305

RESUMO

Superconducting circuits have emerged as a powerful platform of quantum simulation, especially for emulating the dynamics of quantum many-body systems, because of their tunable interaction, long coherence time, and high-precision control. Here in experiments, we construct a Bose-Hubbard ladder with a ladder array of 20 qubits on a 24-qubit superconducting processor. We investigate theoretically and demonstrate experimentally the dynamics of single- and double-excitation states with distinct behaviors, indicating the uniqueness of the Bose-Hubbard ladder. We observe the linear propagation of photons in the single-excitation case, satisfying the Lieb-Robinson bounds. The double-excitation state, initially placed at the edge, localizes; while placed in the bulk, it splits into two single-excitation modes spreading linearly toward two boundaries, respectively. Remarkably, these phenomena, studied both theoretically and numerically as unique properties of the Bose-Hubbard ladder, are represented coherently by pairs of controllable qubits in experiments. Our results show that collective excitations, as a single mode, are not free. This work paves the way to simulation of exotic logic particles by subtly encoding physical qubits and exploration of rich physics by superconducting circuits.

18.
J Med Chem ; 62(17): 7910-7922, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31437392

RESUMO

Drug discovery programs of covalent irreversible, mechanism-based enzyme inhibitors often focus on optimization of potency as determined by IC50-values in biochemical assays. These assays do not allow the characterization of the binding activity (Ki) and reactivity (kinact) as individual kinetic parameters of the covalent inhibitors. Here, we report the development of a kinetic substrate assay to study the influence of the acidity (pKa) of heterocyclic leaving group of triazole urea derivatives as diacylglycerol lipase (DAGL)-α inhibitors. Surprisingly, we found that the reactivity of the inhibitors did not correlate with the pKa of the leaving group, whereas the position of the nitrogen atoms in the heterocyclic core determined to a large extent the binding activity of the inhibitor. This finding was confirmed and clarified by molecular dynamics simulations on the covalently bound Michaelis-Menten complex. A deeper understanding of the binding properties of covalent serine hydrolase inhibitors is expected to aid in the discovery and development of more selective covalent inhibitors.

19.
Nat Mater ; 18(10): 1065-1070, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31384030

RESUMO

The Berry phase of Bloch states can have profound effects on electron dynamics1-3 and lead to novel transport phenomena, such as the anomalous Hall effect and the valley Hall effect4-6. Recently, it was predicted that the Berry phase effect can also modify the exciton states in transition metal dichalcogenide monolayers, and lift the energy degeneracy of exciton states with opposite angular momentum through an effective valley-orbital coupling1,7-11. Here, we report the observation and control of the Berry phase-induced splitting of the 2p exciton states in monolayer molybdenum diselenide (MoSe2) using the intraexciton optical Stark spectroscopy. We observe the time-reversal-symmetric analogue of the orbital Zeeman effect resulting from the valley-dependent Berry phase, which leads to energy difference of +14 (-14) meV between the 2p+ and 2p- exciton states in the K (K') valley, consistent with the ordering from our ab initio GW-Bethe-Salpeter equation results. In addition, we show that the light-matter coupling between intraexciton states is remarkably strong, leading to a prominent valley-dependent Autler-Townes doublet under resonant driving. Our study opens up pathways to coherently manipulate the quantum states and excitonic excitation with infrared radiation in two-dimensional semiconductors.

20.
Medicine (Baltimore) ; 98(34): e16891, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31441866

RESUMO

RATIONALE: Alien Hand syndrome (AHS) is characterized in most patients by seemingly purposeful, involuntary movements of the extremities. It is not well known among physicians on account of its diverse clinical manifestations. PATIENT CONCERNS: We present a 57-year-old Chinese man who could not stop or turn himself around as he involuntarily and uncontrollably walked forward, which had happened frequently in the month prior to treatment. He had been a heavy drinker for thirty years before the onset of the disease, with an alcohol intake of 600 to 800 ml/day. DIAGNOSES: History of alcohol intake and the brain magnetic resonance imaging findings indicated a diagnosis of Marchiafava-Bignami disease. The patient was additionally diagnosed with Alien Hand Syndrome according to his clinical symptoms. INTERVENTIONS: The patient was treated with high doses of vitamin B for 1 month. OUTCOMES: The patient's abnormal behaviors never appeared during the treatment, and no instance of recurrence was observed during the 6 months of follow-up. LESSONS: The clinical manifestation of AHS is non-specific. Only by considering its diverse manifestation can doctors better understand the disease and achieve early intervention.


Assuntos
Síndrome da Mão Alienígena/etiologia , Doença de Marchiafava-Bignami/complicações , Doença de Marchiafava-Bignami/diagnóstico , Alcoolismo/complicações , Síndrome da Mão Alienígena/diagnóstico , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/patologia , Humanos , Imagem por Ressonância Magnética , Masculino , Doença de Marchiafava-Bignami/tratamento farmacológico , Pessoa de Meia-Idade , Tiamina/uso terapêutico , Complexo Vitamínico B/uso terapêutico
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