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2.
Arch Oral Biol ; 141: 105467, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35679800

RESUMO

OBJECTIVE: The aim of this study was to explore the effects and underlying mechanisms of Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS) on the formation of neutrophil extracellular traps (NETs). DESIGN: NETs induced by 1 µg/ml P. gingivalis LPS were observed by a fluorescence microscope and quantified by a microplate reader. Quantities of extra- and intracellular P. gingivalis in neutrophils were determined to assay the bactericidal efficiency of NETs. Intracellular Ca2+ levels in neutrophils were explored by flow cytometry. Expressions of phospho-tumor progression locus 2 (p-TPL2), phospho-mitogen-activated protein kinase kinase1/2 (p-MEK1/2), phospho-extracellular signal-regulated kinase1/2 (p-ERK1/2), ORAI1, ORAI2 and peptidylarginine deiminase 4 (PAD4) were detected by Western blot. In addition, neutrophil elastase activities in NETs incubated with macrophages were assayed to evaluate their clearance. RESULTS: P. gingivalis LPS contributed to the formation of NETs and the increased levels of extracellular DNA (p < 0.05), which enhanced bactericidal activity of neutrophils (p < 0.05). Levels of intracellular Ca2+, p-TPL2, p-MEK1/2, p-ERK1/2, ORAI1, ORAI2 and PAD4 were increased in P. gingivalis LPS-treated neutrophils compared with control group (p < 0.05). In addition, inhibition of intracellular Ca2+ by two Ca2+ chelators, and PAD4 knockdown resulted in decreased levels of extracellular DNA (p < 0.05). After co-culture of NETs with macrophages, neutrophil elastase activities were decreased (p < 0.05). CONCLUSION: P. gingivalis LPS induced the formation of NETs via a Ca2+-TPL2-MEK-ERK-PAD4 signaling pathway, which contribute to the elimination of P. gingivalis.

4.
Curr Biol ; 32(9): 1937-1948.e5, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35338850

RESUMO

Novel targets for treating feeding-related diseases are of great importance, and histamine has long been considered an anorexigenic agent. However, understanding its functions in feeding in a circuit-specific way is still limited. Here, we report a medial septum (MS)-projecting histaminergic circuit mediating feeding behavior. This MS-projecting histaminergic circuit is functionally inhibited during food consumption, and bidirectionally modulates feeding behavior via downstream H2, but not H1, receptors on MS glutamatergic neurons. Further, we observed a pathological decrease of histamine 2 receptors (H2Rs) expression in MS glutamatergic neurons in diet-induced obesity (DIO) mice. Genetically, down-regulation of H2Rs expression in MS glutamatergic neurons accelerates body-weight gain. Importantly, chronic activation of H2Rs in MS glutamatergic neurons (with its clinical agonist amthamine) significantly slowed down the body-weight gain in DIO mice, providing a possible clinical utility to treat obesity. Together, our results demonstrate that this MS-projecting histaminergic circuit is critically involved in feeding, and H2Rs in MS glutamatergic neurons is a promising target for treating body-weight problems.


Assuntos
Comportamento Alimentar , Histamina , Animais , Comportamento Alimentar/fisiologia , Histamina/metabolismo , Histamina/farmacologia , Camundongos , Neurônios/fisiologia , Obesidade/metabolismo , Ganho de Peso
5.
Inflammation ; 45(3): 1174-1185, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35059922

RESUMO

Tolerance is defined to be a hyporesponsive state following repeated stimulations with bacteria or their virulence factors and has potential impacts on the development of periodontitis. Recently, macrophages have been reported to release chromatin and antimicrobial peptides to form extracellular traps upon bacterial or chemical stimulations. Thus, we explored the roles and mechanisms of tolerance induced by Porphyromonas gingivalis (P. gingivalis) in macrophage extracellular traps (METs). Tolerance in peritoneal macrophages from mice was triggered by repeated P. gingivalis stimulation. METs were observed using fluorescence microscopy, and the levels of extracellular DNA were determined by microplate reader assays. The expression of p-RAF, p-MEK, and p-ERK was examined by Western blot, and reactive oxygen species (ROS) production was explored using flow cytometry. Moreover, the levels of intracellular Ca2+ were also determined by confocal microscopy to identify the possible mechanisms related to the changes in METs in P. gingivalis-pretreated macrophages. Repeated P. gingivalis stimulation contributed to the formation of METs and increased levels of extracellular DNA (p < 0.05). ROS generation and RAF/MEK/ERK phosphorylation were decreased in P. gingivalis-pretreated macrophages compared with non-pretreated cells (p < 0.05), which was inconsistent with the changes in METs. However, in P. gingivalis-pretreated macrophages, the levels of intracellular Ca2+ were significantly increased compared with the single stimulation group. Additionally, inhibition of intracellular Ca2+ resulted in a decrease in the levels of extracellular DNA in P. gingivalis-pretreated cells (p < 0.05). Taken together, P. gingivalis-pretreated macrophages released more METs, possibly related to the increased levels of intracellular Ca2+.


Assuntos
Armadilhas Extracelulares , Porphyromonas gingivalis , Animais , Armadilhas Extracelulares/metabolismo , Macrófagos/metabolismo , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
J Phys Chem Lett ; 13(2): 520-526, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35005955

RESUMO

It is critical to identify the influence of phosphine ligands on cross-coupling reactions to obtain a higher yield. In order to reveal ligands' effects, many descriptors have been proposed, which allow statistical analysis to be implemented in mining the structure-property relationship and providing mechanistic insights. This work combines the steric and electronic effects into a descriptor, %Vbur (min) - 3·HOMO-LUMO gap (eV) where %Vbur (min) is the minimum percent buried volume and the Boltzmann averaged gap is used. Volcano plots were well presented by yields (y-axis) and the descriptor (x-axis) for Ni- and Pd-catalyzed cross-coupling reactions. In addition, volcano peaks in these plots can be located to optimize reaction yields for experiments. Our work sheds light on the reaction mechanisms of phosphine ligands and delivers a strategy for choosing ligands in cross-coupling catalysis.

7.
Phys Rev E ; 104(5-1): 054502, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34942690

RESUMO

In this work, we report an intriguing phenomenon: crowding-induced polymer trapping in a channel. Using Langevin dynamics simulations and analytical calculations, we find that for a polymer confined in a channel, crowding particles can push a polymer into the channel corner through inducing an effective polymer-corner attraction due to the depletion effect. This phenomenon is referred to as polymer trapping. The occurrence of polymer trapping requires a minimum volume fraction of crowders, ϕ^{*}, which scales as ϕ^{*}∼(a_{c}/L_{p})^{1/3} for a_{c}≫a_{m} and ϕ^{*}∼(a_{c}/L_{p})^{1/3}(a_{c}/a_{m})^{1/2} for a_{c}≪a_{m}, where a_{c} is the crowder diameter, a_{m} is the monomer diameter, and L_{p} is the polymer persistence length. For DNA, ϕ^{*} is estimated to be around 0.25 for crowders with a_{c}=2nm. We find that ϕ^{*} also strongly depends on the shape of the channel cross section, and ϕ^{*} is much smaller for a triangle channel than a square channel. The polymer trapping leads to a nearly fully stretched polymer conformation along a channel corner, which may have practical applications, such as full stretching of DNA for the nanochannel-based genome mapping technology.

8.
Int J Mol Sci ; 22(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34639201

RESUMO

The arsenic acid-resistant (ArsR) family transcriptional regulators are widely distributed in microorganisms, including in the facultative intracellular pathogen Brucella spp. ArsR proteins are implicated in numerous biological processes. However, the specific roles of ArsR family members in Brucella remain obscure. Here, we show that ArsR6 (BSS2_RS07325) is required for Brucella survival both under heat, oxidative, and osmotic stress and in a murine infection model in vivo. RNA-seq and ChIP-seq reveal that 34 potential target genes for ArsR6 protein were identified, among which eight genes were up-regulated and 26 genes were down-regulated, including outer membrane protein 25D (Omp25D). ArsR6 autoregulates its own expression to maintain bacterial intracellular Cu/Ni homeostasis to benefit bacterial survival in hostile environments. Moreover, ArsR6 also regulates the production of virulence factor Omp25D, which is important for the survival of Brucella under stress conditions. Significantly, Omp25D deletion strain attenuated in a murine infection model in vivo. Altogether, our findings reveal a unique mechanism in which the ArsR family member ArsR6 autoregulates its expression and also modulates Omp25D expression to maintain metal ion homeostasis and virulence in Brucella.


Assuntos
Proteínas de Bactérias/metabolismo , Brucella/crescimento & desenvolvimento , Brucelose/microbiologia , Regulação Bacteriana da Expressão Gênica , Transativadores/metabolismo , Fatores de Virulência/metabolismo , Virulência , Animais , Brucella/genética , Brucella/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Transativadores/genética , Fatores de Virulência/genética
9.
Sci Rep ; 11(1): 16492, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389742

RESUMO

Heat shock transcription factors (HSFs) are central elements in the regulatory network that controls plant heat stress response. They are involved in multiple transcriptional regulatory pathways and play important roles in heat stress signaling and responses to a variety of other stresses. We identified 41 members of the HSF gene family in moso bamboo, which were distributed non-uniformly across its 19 chromosomes. Phylogenetic analysis showed that the moso bamboo HSF genes could be divided into three major subfamilies; HSFs from the same subfamily shared relatively conserved gene structures and sequences and encoded similar amino acids. All HSF genes contained HSF signature domains. Subcellular localization prediction indicated that about 80% of the HSF proteins were located in the nucleus, consistent with the results of GO enrichment analysis. A large number of stress response-associated cis-regulatory elements were identified in the HSF upstream promoter sequences. Synteny analysis indicated that the HSFs in the moso bamboo genome had greater collinearity with those of rice and maize than with those of Arabidopsis and pepper. Numerous segmental duplicates were found in the moso bamboo HSF gene family. Transcriptome data indicated that the expression of a number of PeHsfs differed in response to exogenous gibberellin (GA) and naphthalene acetic acid (NAA). A number of HSF genes were highly expressed in the panicles and in young shoots, suggesting that they may have functions in reproductive growth and the early development of rapidly-growing shoots. This study provides fundamental information on members of the bamboo HSF gene family and lays a foundation for further study of their biological functions in the regulation of plant responses to adversity.


Assuntos
Fatores de Transcrição de Choque Térmico/genética , Proteínas de Plantas/genética , Sasa/genética , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Estudo de Associação Genômica Ampla , Fatores de Transcrição de Choque Térmico/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Sasa/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA
10.
Phys Chem Chem Phys ; 23(32): 17545-17552, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34369534

RESUMO

Recently, a new carbon allotrope, cyclo[18]carbon, of alternating short and long carbon-carbon bonds has been synthesized and characterized in the condensed phase. Inspired by experiments, a lot of theoretical studies involving adsorption, aromaticity, catalysis and spectra have been performed. Although cyclo[18]carbon is generally regarded as an unstable molecule, the theoretical explanation of its instability is still inadequate. In this work, we studied the intermediate process of reactions between cyclo[18]carbon and triplet oxygen by density functional theory calculations. The reaction is expected to happen easily because the maximal reaction energy barrier is less than 1 eV, and cyclo[16]carbon, cyclo[17]carbon and straight-chain C18O2 molecules have been considered as possible products. Infrared and Raman spectra were calculated to help in differentiating the final products. The thermal stability of cyclo[17]carbon is rather weak according to ab initio molecular dynamics simulations. This work sheds light on the synthesis of other cyclo[n]carbons and cumulenes by utilizing cyclo[18]carbon.

11.
BMC Genomics ; 22(1): 533, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34256690

RESUMO

BACKGROUND: The BBX (B-box) family are zinc finger protein (ZFP) transcription factors that play an essential role in plant growth, development and response to abiotic stresses. Although BBX genes have been characterized in many model organisms, genome-wide identification of the BBX family genes have not yet been reported in Moso bamboo (Phyllostachys edulis), and the biological functions of this family remain unknown. RESULT: In the present study, we identified 27 BBX genes in the genome of Moso bamboo, and analysis of their conserved motifs and multiple sequence alignments revealed that they all shared highly similar structures. Additionally, phylogenetic and homology analyses indicated that PeBBX genes were divided into three clusters, with whole-genome duplication (WGD) events having facilitated the expansion of this gene family. Light-responsive and stress-related cis-elements were identified by analyzing cis-elements in the promoters of all PeBBX genes. Short time-series expression miner (STEM) analysis revealed that the PeBBX genes had spatiotemporal-specific expression patterns and were likely involved in the growth and development of bamboo shoots. We further explored the downstream target genes of PeBBXs, and GO/KEGG enrichment analysis predicted multiple functions of BBX target genes, including those encoding enzymes involved in plant photosynthesis, pyruvate metabolism and glycolysis/gluconeogenesis. CONCLUSIONS: In conclusion, we analyzed the PeBBX genes at multiple different levels, which will contribute to further studies of the BBX family and provide valuable information for the functional validation of this family.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Poaceae , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poaceae/genética , Poaceae/metabolismo , Fatores de Transcrição/genética
12.
BMC Plant Biol ; 21(1): 296, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34182934

RESUMO

BACKGROUND: Moso bamboo, the fastest growing plant on earth, is an important source for income in large areas of Asia, mainly cultivated in China. Lateral organ boundaries domain (LBD) proteins, a family of transcription factors unique to plants, are involved in multiple transcriptional regulatory pathways and play important roles in lateral organ development, pathogen response, secondary growth, and hormone response. The LBD gene family has not previously been characterized in moso bamboo (Phyllostachys edulis). RESULTS: In this study, we identified 55 members of the LBD gene family from moso bamboo and found that they were distributed non-uniformly across its 18 chromosomes. Phylogenetic analysis showed that the moso bamboo LBD genes could be divided into two classes. LBDs from the same class share relatively conserved gene structures and sequences encoding similar amino acids. A large number of hormone response-associated cis-regulatory elements were identified in the LBD upstream promoter sequences. Synteny analysis indicated that LBDs in the moso bamboo genome showed greater collinearity with those of O. sativa (rice) and Zea mays (maize) than with those of Arabidopsis and Capsicum annuum (pepper). Numerous segmental duplicates were found in the moso bamboo LBD gene family. Gene expression profiles in four tissues showed that the LBD genes had different spatial expression patterns. qRT-PCR assays with the Short Time-series Expression Miner (STEM) temporal expression analysis demonstrated that six genes (PeLBD20, PeLBD29, PeLBD46, PeLBD10, PeLBD38, and PeLBD06) were consistently up-regulated during the rapid growth and development of bamboo shoots. In addition, 248 candidate target genes that function in a variety of pathways were identified based on consensus LBD binding motifs. CONCLUSIONS: In the current study, we identified 55 members of the moso bamboo transcription factor LBD and characterized for the first time. Based on the short-time sequence expression software and RNA-seq data, the PeLBD gene expression was analyzed. We also investigated the functional annotation of all PeLBDs, including PPI network, GO, and KEGG enrichment based on String database. These results provide a theoretical basis and candidate genes for studying the molecular breeding mechanism of rapid growth of moso bamboo.


Assuntos
Genes de Plantas/genética , Poaceae/genética , Fatores de Transcrição/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Sequência Conservada , Evolução Molecular , Regulação da Expressão Gênica de Plantas/genética , Estudo de Associação Genômica Ampla , Filogenia , Alinhamento de Sequência , Transcriptoma
13.
PLoS One ; 16(3): e0248318, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33724993

RESUMO

Dirigent-jacalin (D-J) genes belong to the plant chimeric lectin family, and play vital roles in plant growth and resistance to abiotic and biotic stresses. To explore the functions of the D-J family in the growth and development of Moso bamboo (Phyllostachys edulis), their physicochemical properties, phylogenetic relationships, gene and protein structures, and expression patterns were analyzed in detail. Four putative PeD-J genes were identified in the Moso bamboo genome, and microsynteny and phylogenetic analyses indicated that they represent a new branch in the evolution of plant lectins. PeD-J proteins were found to be composed of a dirigent domain and a jacalin-related lectin domain, each of which contained two different motifs. Multiple sequence alignment and homologous modeling analysis indicated that the three-dimensional structure of the PeD-J proteins was significantly different compared to other plant lectins, primarily due to the tandem dirigent and jacalin domains. We surveyed the upstream putative promoter regions of the PeD-Js and found that they mainly contained cis-acting elements related to hormone and abiotic stress response. An analysis of the expression patterns of root, leaf, rhizome and panicle revealed that four PeD-J genes were highly expressed in the panicle, indicating that they may be required during the formation and development of several different tissue types in Moso bamboo. Moreover, PeD-J genes were shown to be involved in the rapid growth and development of bamboo shoots. Quantitative Real-time PCR (qRT PCR) assays further verified that D-J family genes were responsive to hormones and stresses. The results of this study will help to elucidate the biological functions of PeD-Js during bamboo growth, development and stress response.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Lectinas de Plantas/genética , Poaceae/fisiologia , Adaptação Biológica/genética , Sequência Conservada , Perfilação da Expressão Gênica , Genoma de Planta/genética , Estudo de Associação Genômica Ampla , Filogenia , Regiões Promotoras Genéticas , Estrutura Terciária de Proteína/genética , Estresse Fisiológico
14.
Front Plant Sci ; 12: 809666, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095981

RESUMO

Jacalin-related lectins (JRLs) are a new subfamily of plant lectins that has recently been recognized and plays an important role in plant growth, development, and abiotic stress response. Although moso bamboo (Phyllostachys edulis) is an economically and industrially important bamboo worldwide, there has been no systematic identification of JRLs in this species. Here, we identified 25 JRL genes in moso bamboo, and these genes are unequally distributed among 10 genome scaffolds. Phylogenetic analysis showed that the moso bamboo JRLs were clustered into four JRL subgroups: I, II, V, and VII. Numerous stress-responsive and hormone-regulated cis-elements were detected in the upstream promoter regions of the JRLs. Genome collinearity analyses showed that the JRL genes of moso bamboo are more closely related to those of Brachypodium distachyon than to those of Oryza sativa and Zea mays. Sixty-four percent of the PeJRL genes are present as segmental and tandem duplicates. qRT-PCR expression analysis showed that JRL genes in the same subgroup were significantly downregulated in response to salicylic acid (SA), abscisic acid (ABA), and methyl jasmonate (MeJA) treatments and significantly upregulated under low temperature, drought, and salt stress; they also exhibited tissue-specific expression patterns. Subcellular localization experiments revealed that PeJRL04 and PeJRL13 were localized to the cell membrane, nucleus, and cytoplasm. Three dimensional structure prediction and yeast two-hybrid assays were used to verify that PeJRL13 exists as a self-interacting homodimer in vivo. These findings provide an important reference for understanding the functions of specific moso bamboo JRL genes and for the effective selection of stress-related genes.

15.
Shanghai Kou Qiang Yi Xue ; 29(4): 359-364, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-33089282

RESUMO

PURPOSE: The aim of the present study was to investigate the effect of curcumin (Cur) on TGF-ß1/Smad3 pathway of rat gingival fibroblast treated with cyclosporine A (CsA) in vitro, and to provide theoretical basis for the mechanism of curcumin inhibiting drug-induced gingival hyperplasia induced by CsA. METHODS: Healthy Sprague-Dawley rat gingival fibroblasts were cultured with different concentrations of Cur (0, 5, 10, 20, 30 µmol/L) and Cur (20 µmol/L)+CsA(200 ng/mL), cell proliferation was assessed with CCK-8 assay. The mRNA levels of TGF-ß1, Smad3, α-SMA and collagen type Ⅰ in gingival fibroblasts were detected by real-time PCR under Cur(20 µmol/L)+CsA(200 ng/mL); the protein level of TGF-ß1, Smad3, p-Smad3, α-SMA and collagen type Ⅰ were determined through Western blot. The effect of Cur(20 µmol/L)+CsA(200 ng/mL) on migration ability of gingival fibroblasts was observed through Scratch wound-healing assay. The data were analyzed with SPSS 23.0 software package. RESULTS: Cell proliferation and migration ability of rats gingival fibroblasts were significantly reduced under Cur(20 µmol/L)+CsA(200 ng/mL). 20 µmol/L Cur significantly decreased mRNA expression of TGF-ß1, α-SMA and collagen type Ⅰ in gingival fibroblasts, and Western blot suggested significantly down-regulated expression of TGF-ß1, p-Smad3, α-SMA, and collagen typeⅠ. CONCLUSIONS: Cur may inhibit TGF-ß1/Smad3 signaling pathway of gingival fibroblasts activated by CsA, thereby weakening proliferation and migration, reducing secretion of smooth muscle actin and collagen of gingival fibroblasts, and ameliorating gingival hyperplasia.


Assuntos
Curcumina , Fator de Crescimento Transformador beta1 , Animais , Curcumina/farmacologia , Ciclosporina/farmacologia , Fibroblastos , Ratos , Ratos Sprague-Dawley
16.
Microb Pathog ; 149: 104587, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33091579

RESUMO

INTRODUCTION: Toxoplasma gondii (T. gondii), a parasitic protozoa that is associated with various psychiatric disorders. Both T. gondii infection and disturbed host's lipid profile are common in schizophrenia patients. However, the underlying pathophysiological mechanisms remain speculative. Also, the characteristics of serum lipid levels in schizophrenia patients comorbid with T. gondii infection are not clear. Therefore, it is necessary to explore the influence of chronic T. gondii infection on the characteristic physiological indexes of schizophrenia patients so as to provide some insights into finding target therapeutic drugs. METHODS: In this study, the effect of chronic T. gondii infection on serum lipid profile was retrospectively analysed in 1719 schizophrenic patients and 1552 healthy subjects from Eastern China. RESULTS: The overall prevalence of Immunoglobulin G (IgG) antibodies against T. gondii (17.98%) in schizophrenia patients was significantly higher than healthy controls (7.35%, χ2 = 81.831, P = 0.000). Compared to T. gondii IgG-seronegative schizophrenia patients, IgG-seropositive group had higher high-density lipoprotein (HDL) (P = 0.000) and triglycerides (TG) (P = 0.000) levels, while total cholesterol (TC) (P = 0.000) levels showed an opposite tendency in IgG-seropositive cases. We also found significant correlation between T. gondii seropositivity and increased TG (P = 0.000) and TC levels (P = 0.000) in schizophrenia patients. Binary regression analysis also showed that decreased TC level was more common among schizophrenia patients with T. gondii seropositivity compared to seronegative subjects (OR = 0.617, 95%CI = 0.509-0.749, P = 0.000). CONCLUSION: Patients with chronic T. gondii infection and comorbid schizophrenia had higher HDL and TG levels, while cholesterol levels showed an opposite trend. To the best of our knowledge, this is the first report focus on the host's lipid profile of chronic T. gondii infection and comorbid schizophrenia patients.


Assuntos
Esquizofrenia , Toxoplasma , Toxoplasmose , Anticorpos Antiprotozoários , China/epidemiologia , Comorbidade , Humanos , Lipídeos , Estudos Retrospectivos , Esquizofrenia/complicações , Esquizofrenia/epidemiologia , Estudos Soroepidemiológicos , Toxoplasmose/complicações , Toxoplasmose/epidemiologia
17.
Nat Commun ; 11(1): 2531, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439875

RESUMO

Solar-driven CO2 reduction by abundant water to alcohols can supply sustainable liquid fuels and alleviate global warming. However, the sluggish water oxidation reaction has been hardly reported to be efficient and selective in CO2 conversion due to fast charge recombination. Here, using transient absorption spectroscopy, we demonstrate that microwave-synthesised carbon-dots (mCD) possess unique hole-accepting nature, prolonging the electron lifetime (t50%) of carbon nitride (CN) by six folds, favouring a six-electron product. mCD-decorated CN stably produces stoichiometric oxygen and methanol from water and CO2 with nearly 100% selectivity to methanol and internal quantum efficiency of 2.1% in the visible region, further confirmed by isotopic labelling. Such mCD rapidly extracts holes from CN and prevents the surface adsorption of methanol, favourably oxidising water over methanol and enhancing the selective CO2 reduction to alcohols. This work provides a unique strategy for efficient and highly selective CO2 reduction by water to high-value chemicals.

18.
ACS Nano ; 14(5): 5636-5648, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32315150

RESUMO

The metallic, 1T polymorph of molybdenum disulfide (MoS2) is promising for next-generation supercapacitors due to its high theoretical surface area and density which lead to high volumetric capacitance. Despite this, there are few fundamental works examining the double-layer charging mechanisms at the MoS2/electrolyte interface. This study examines the potential-dependent and frequency-dependent area-specific double-layer capacitance (Ca) of the 1T and 2H polymorphs of MoS2 in aqueous and organic electrolytes. Furthermore, we investigate restacking effects and possible intercalation-like mechanisms in multilayer films. To minimize the uncertainties associated with porous electrodes, we carry out measurements using effectively nonporous monolayers of MoS2 and contrast their behavior with reduced graphene oxide deposited layer-by-layer on atomically flat graphite single crystals using a modified, barrier-free Langmuir-Blodgett method. The metallic 1T polymorph of MoS2 (Ca,1T = 14.9 µF/cm2) is shown to have over 10-fold the capacitance of the semiconducting 2H polymorph (Ca,2H = 1.35 µF/cm2) near the open circuit potential and under negative polarization in aqueous electrolyte. However, under positive polarization the capacitance is significantly reduced and behaves similarly to the 2H polymorph. The capacitance of 1T MoS2 scales with layer number, even at high frequency, suggesting easy and rapid ion penetration between the restacked sheets. This model system allows us to determine capacitance limits for MoS2 and suggest strategies to increase the energy density of devices made from this promising material.

19.
Int J Nurs Stud ; 105: 103554, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32200101

RESUMO

BACKGROUND: There is a shortage of nurses worldwide, and a large number of older nurses will be entering retirement in the near future. Older nurses have rich nursing experience, and their retirement is a major loss of resources for the nursing profession. Returning to work after retirement is becoming increasingly popular among retirees today, but there is limited knowledge of the perceptions of older nurses regarding continuing to work in a nursing career after retirement. OBJECTIVES: To explore older nurses' perceptions of continuing to work in a nursing career after retirement. DESIGN AND SETTINGS: We conducted a descriptive, qualitative study of older nurses from two public hospitals of different levels in China in 2018. PARTICIPANTS: A total of 27 older nurses aged 50-60 years were recruited, 15 from a tertiary hospital and 12 from a secondary hospital. METHODS: Individual semi-structured interviews were conducted with older nurses. An interview guide was developed to explore nurses' perceptions of continuing to work in a nursing career after retirement. Thematic analysis was used for the data analysis. We developed an interview guide and analysed the data based on the three essential conditions of the framework for understanding behaviour. FINDINGS: Based on the definition of the three essential conditions of the framework for understanding behaviour, 14 subthemes emerged from the data were categorised under this framework. The three main themes were as follows: the nurses' perceptions of their capability, motivation, and opportunity related to engaging in a nursing career after retirement. A number of older nurses with rich clinical experience have the ability and motivation to engage in nursing a career after retirement. However, discrimination against nurses, burnout, and the effects on young people's employment are barriers to older nurses considering working in a nursing career after retirement. Regarding re-employment after retirement, older nurses also expressed concerns about their physical health, family responsibilities, and salary as well as lack of managerial and policy support. CONCLUSIONS: These themes confirmed previous findings and offered new perspectives on older Chinese nurses' perceptions of working in a nursing career after retirement. These findings will influence future policy development and research directions. Policies for facilitating a prolonged working life should be developed. Future research should focus on how to address the challenges confronted by older nurses.


Assuntos
Atitude do Pessoal de Saúde , Recursos Humanos de Enfermagem no Hospital , Aposentadoria , China , Feminino , Hospitais , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade
20.
Medicine (Baltimore) ; 98(49): e18162, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31804329

RESUMO

RATIONALE: The prognosis of lung cancer is dismal, which has resulted in lung carcinoma being one of the leading causes of cancer-related deaths worldwide. Non-small cell lung cancer accounts for approximately 80% of all types of lung carcinoma. The skeletal system and central nervous system are the most common distal metastatic sites in patients with lung cancer, while cutaneous and soft tissues metastasis is rare. PATIENT CONCERNS: We report a case of concomitant metastasis in the nasal tip and suspected buttocks metastasis secondary to lung cancer, who complained of repeated cough and white sputum for 6 months. DIAGNOSE: Primary lung cancer was diagnosed by bronchoscopy and biopsy, lesion on nasal tip was confirmed by biopsy. Furthermore, PET-CT scan identified the untouchable buttocks lesion that could have been easily missed. INTERVENTIONS: This patient refused systemic treatments, but he chose traditional Chinese medicine at home. OUTCOMES: He died 6 months after the diagnosis. LESSONS: The possibility of metastasis of primary cancers should be considered when encountering soft-tissue neoplasm lesions, and a biopsy of the suspicious cutaneous lesions could likely aid in the histological identification of the primary cancer. PET-CT scan could be an effective supplementary tool for the diagnosis and evaluation of cancers.


Assuntos
Neoplasias Pulmonares/patologia , Neoplasias Cutâneas/secundário , Neoplasias de Tecidos Moles/secundário , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
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