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1.
Emerg Microbes Infect ; 8(1): 1229-1239, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31448697

RESUMO

Lysine acetylation and succinylation are both prevalent protein post-translational modifications (PTMs) in bacteria species, whereas the effect of the cross-talk between both PTMs on bacterial biological function remains largely unknown. Our previously study found lysine succinylated sites on proteins play important role on metabolic pathways in fish pathogenic Aeromonas hydrophila. A total of 3189 lysine-acetylation sites were further identified on 1013 proteins of this pathogen using LC-MS/MS in this study. Functional examination of these PTMs peptides showed associations with basal biological processes, especially metabolic pathways. Additionally, when comparing the obtained lysine acetylome to a previously obtained lysine succinylome, 1198 sites in a total of 547 proteins were found to be in common and associated with various metabolic pathways. As the autoinducer-2 (AI-2) synthase involved in quorum sensing of bacteria, the site-directed mutagenesis of LuxS at the K165 site was performed and revealed that the cross-talk between lysine acetylation and succinylation exerts an inverse influence on bacterial quorum sensing and on LuxS enzymatic activity. In summary, this study provides an in-depth A. hydrophila lysine acetylome profile and for the first time reveals the role of cross-talk between lysine acetylation and succinylation, and its potential impact on bacterial physiological functions.

2.
World J Microbiol Biotechnol ; 35(8): 127, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375931

RESUMO

Aeromonas hydrophila is a Gram-negative bacterium that causes serious infections in aquaculture and exhibits significant multidrug resistance. The LysR-type transcriptional regulator (LTTR) family proteins are a well-known group of transcriptional regulators involved in diverse physiological functions. However, the role of LTTRs in the regulation of bacterial resistance to antibiotics is still largely unknown. In this study, to further investigate the role of four putative LTTR family proteins (A0KIU1, A0KJ82, A0KPK0, and A0KQ63) in antibiotic resistance in A. hydrophila, their genes were cloned and overexpressed in engineered Escherichia coli. After the optimization of experimental conditions including incubation time, temperature, and IPTG concentration, these proteins were successfully purified, and their specific antibodies against mice were obtained. Using western blot analysis, we found that these LTTR family proteins were downregulated in A. hydrophila following antibiotic treatment, indicating that they may be involved in the regulation of antibiotic resistance. Additionally, minimum inhibitory concentration (MIC) assays of chloramphenicol (CM), chlortetracycline (CTC), ciprofloxacin (CF), furazolidone (FZ), and balofloxacin (BF) in E. coli showed that overexpression of these LTTRs led to increased sensitivity to several antibiotics. To further validate their functional role in antibiotic resistance, we demonstrated that bacteria with loss of A0KQ63 (ΔAHA_3980) exhibited multi-drug resistance properties. Our results indicate that these LTTR family proteins may play an important role in the antibiotic resistance of A. hydrophila, and the that underlying mechanisms controlling antibiotic resistance should be further investigated.


Assuntos
Aeromonas hydrophila/efeitos dos fármacos , Aeromonas hydrophila/genética , Farmacorresistência Bacteriana , Regulação Bacteriana da Expressão Gênica , Genes Reguladores , Fatores de Transcrição/metabolismo , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Western Blotting , Clonagem Molecular , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Deleção de Genes , Expressão Gênica , Perfilação da Expressão Gênica , Genes Bacterianos , Camundongos , Testes de Sensibilidade Microbiana , Fatores de Transcrição/análise , Fatores de Transcrição/genética
3.
Cell Biol Int ; 43(7): 799-808, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31050064

RESUMO

Muscle satellite cells are usually at rest, and when externally stimulated or regulated, they can be further differentiated by cell fusion to form new myotubes and muscle fibers. WD repeat domain 13 (WDR13) is highly conserved in vertebrates. Studies have shown that mice lacking the Wdr13 gene develop mild obesity, hyperinsulinemia, and increased islet ß cell proliferation. However, the role of WDR13 in bovine cells is unclear. Here, we investigated the effect of WDR13 on bovine skeletal muscle-derived satellite cells (MDSCs). We found that WDR13 was upregulated in bovine MDSCs using western blotting and immunofluorescence experiments. Moreover, activation and inhibition of WDR13 expression increased and decreased cell differentiation, respectively, suggesting that WDR13 promotes bovine MDSC differentiation. To further understand the mechanism of action of WDR13, we examined changes in the PI3K/AKT signaling pathway following WDR13 activation or inhibition. In addition, cells were treated with a phosphoinositide kinase 3 (PI3K) inhibitor, LY294004, to observe cell differentiation. The results showed that activation of WDR13 inhibited the PI3K/AKT signaling pathway and enhanced cell differentiation. These data suggest that WDR13 can promote the differentiation of bovine MDSCs by affecting the PI3K/AKT signaling pathway.

4.
J Cell Physiol ; 234(11): 21211-21223, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31025379

RESUMO

The glucose-regulated endoplasmic reticulum chaperone protein 94 (GRP94) is required for many biological processes, such as secretion of immune factors and mesoderm induction. Here, we demonstrated that GRP94 promotes muscle differentiation in vitro and in vivo. Moreover, GRP94 inhibited the PI3K/AKT/mTOR signaling pathway. Using both in vitro and in vivo approaches, in myoblasts, we found that this inhibition resulted in reduced proliferation and increased differentiation. To further investigate the mechanism of GRP94-induced muscle differentiation, we used co-immunoprecipitation and proximity ligation assays and found that GRP94 interacted with PI3K-interacting protein 1 (Pik3ip1). The latter protein promoted muscle differentiation by inhibiting the PI3K/AKT/mTOR pathway. Furthermore, GRP94 was found to regulate Pik3ip1 expression. Finally, when Pik3ip1 expression was inhibited, GRP94-induced promotion of muscle differentiation was diminished. Taken together, our data demonstrated that GRP94 promoted muscle differentiation, mediated by Pik3ip1-dependent inhibition of the PI3K/AKT/mTOR signaling pathway.

5.
Molecules ; 24(7)2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970602

RESUMO

Polyamines have been reported to be involved in grain filling and they might contribute to the construction of heat resistance of some cereals. In this study, the hybrid rice 'YLY 689' was used to explore the possible effects of exogenous spermidine (Spd) on seed quality under high temperature during the filling stage. Rice spikes were treated with Spd or its synthesis inhibitor cyclohexylamine (CHA) after pollination, and then the rice plants were transferred to 40 °C for 5-day heat treatment. The results showed that, compared with the control under high temperature, Spd pretreatment significantly improved the germination percentage, germination index, vigor index, seedling shoot height, and dry weight of seeds harvested at 35 days after pollination, while the CHA significantly decreased the seed germination and seedling growth. Meanwhile, Spd significantly increased the peroxidase (POD) activity and decreased the malondialdehyde (MDA) content in seeds. In addition, after spraying with Spd, the endogenous content of spermidine and spermine and the expression of their synthetic genes, spermidine synthase (SPDSYN) and spermine synthase (SPMS1 and SPMS2), significantly increased, whereas the accumulation of amylose and total starch and the expression of their related synthase genes, soluble starch synthase II-3 (SS II-3) and granules bound starch synthase I (GBSSI), also increased to some extent. The data suggests that exogenous Spd pretreatment could alleviate the negative impacts of high temperature stress on rice seed grain filling and improve the rice seed quality to some extent, which might be partly caused by up-regulating endogenous polyamines and starch metabolism.


Assuntos
Germinação/efeitos dos fármacos , Temperatura Alta , Oryza/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Espermidina/farmacologia , Termotolerância/efeitos dos fármacos
6.
Front Immunol ; 10: 256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30833947

RESUMO

In our previous study, several iron-related outer membrane proteins in Aeromonas hydrophila, a serious pathogen of farmed fish, conferred high immunoprotectivity to fish, and were proposed as potential vaccine candidates. However, the protective efficacy of these extracellular proteins against A. hydrophila remains largely unknown. Here, we identified secreted proteins that were differentially expressed in A. hydrophila LP-2 in response to iron starvation using an iTRAQ-based quantitative proteomics method. We identified 341 proteins, of which 9 were upregulated in response to iron starvation and 24 were downregulated. Many of the differently expressed proteins were associated with protease activity. We confirmed our proteomics results with Western blotting and qPCR. We constructed three mutants by knocking out three genes encoding differentially expressed proteins (Δorf01830, Δorf01609, and Δorf03641). The physiological characteristics of these mutants were investigated. In all these mutant strains, protease activity decreased, and Δorf01609, and Δorf01830 were less virulent in zebrafish. This indicated that the proteins encoded by these genes may play important roles in bacterial infection. We next evaluated the immune response provoked by the six iron-related recombinant proteins (ORF01609, ORF01830, ORF01839, ORF02943, ORF03355, and ORF03641) in zebrafish as well as the immunization efficacy of these proteins. Immunization with these proteins significantly increased the zebrafish immune response. In addition, the relative percent survival (RPS) of the immunized zebrafish was 50-80% when challenged with three virulent A. hydrophila strains, respectively. Thus, these extracellular secreted proteins might be effective vaccine candidates against A. hydrophila infection in fish.

7.
Int J Nanomedicine ; 14: 1805-1815, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880981

RESUMO

Purpose: Resistant strains of Acinetobacter baumannii (AB) that can form biofilms are resistant to polymyxin. Therefore, effective and safe polymyxin preparations against biofilm-producing AB are urgently needed. This study aims to prepare chitosan-modified polymyxin B-loaded liposomes (CLPs) and ultrasound microbubbles (USMBs) and then explore the synergistic antibacterial effects of USMBs combined with CLPs in vitro. Methods: CLPs were prepared using a modified injection method, and microbubbles were prepared using a simple mechanical vibration method. Minimal biofilm inhibitory concentration (MBIC) of CLPs against resistant biofilm-producing AB was determined. Antibacterial activities of CLPs with or without USMBs were analyzed by crystal violet staining and resazurin assays to evaluate biofilm mass and viable counts, respectively. Then, the anti-biofilm effects of CLPs with or without USMBs on biofilm-producing AB were confirmed via scanning electron microscopy (SEM) analysis. Results: We prepared CLPs that were 225.17±17.85 nm in size and carried positive charges of 12.64±1.44 mV. These CLPs, with higher encapsulation efficiency and drug loading, could exhibit a sustained release effect. We prepared microbubbles that were 2.391±0.052 µm in size and carried negative charges of -4.32±0.43 mV. The MBICs of the CLPs on the biofilm-producing AB was 8±2 µg/mL, while that of polymyxin B was 32±2 µg/mL. USMBs in combination with 2 µg/mL of polymyxin B could completely eliminate the biofilm-producing AB and achieve the maximum antimicrobial effects (P>0.05 vs sterile blank control). SEM imaging revealed some scattered bacteria without a biofilm structure in the USMB combined with the CLP group, confirming that this combination has the greatest anti-biofilm effects. Conclusion: In this research, we successfully prepared USMBs and CLPs that have a more significant antibacterial effect on biofilm-forming AB than polymyxin B alone. Experiments in vitro indicate that the synergistic antibacterial effect of combining USMBs with CLPs containing as little as 2 µg/mL of polymyxin B is sufficient to almost eliminate drug-resistant biofilm-producing AB.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/fisiologia , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Quitosana/química , Microbolhas , Polimixina B/farmacologia , Ultrassom , Acinetobacter baumannii/ultraestrutura , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Humanos , Lipossomos , Testes de Sensibilidade Microbiana
8.
Food Funct ; 10(2): 635-645, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30648709

RESUMO

The design of zein-based nanoparticles to encapsulate bioactive molecules has gained great attention in recent years. However, the use of ethanol to dissolve zein presents flammability concerns and the scale-up production of zein-based nanoparticles is also a concern. In our study, propolis loaded zein/caseinate/alginate nanoparticles were fabricated using a facile one-step procedure: a well-blended solution was prepared containing deprotonated propolis, soluble zein, dissociated sodium caseinate micelles (NaCas) and alginate at alkaline pH, and then this alkaline solution was added to 0.1 M citrate buffer (pH 3.8) to fabricate composite nanoparticles without using organic solvents and sophisticated equipment. During acidification, the alginate molecules adsorbed on the zein/NaCas surfaces by electrostatic complexation, which improved the stability towards aggregation of zein/NaCas nanoparticles under gastrointestinal (GI) or acidic pH. The nanoparticles prepared under the optimized method (method 3 sample) were of spherical morphology with a particle size around 208 nm and a negative zeta potential around -27 mV. The encapsulation efficiency (EE) and loading capacity (LC) of propolis reached 86.5% and 59.6 µg mg-1 by zein/NaCas/alginate nanoparticles, respectively. These nanoparticles were shown to be stable towards aggregation over a wide range of pH values (2-8) and salt concentrations (0-300 mM NaCl). Compared to free propolis, the bioaccessibility of propolis encapsulated with nanoparticles was increased to 80%. Our results showed a promising clean and scalability strategy to encapsulate hydrophobic nutraceuticals for applications in foods, supplements, and pharmaceuticals.


Assuntos
Alginatos/química , Caseínas/química , Nanopartículas/química , Própole/química , Zeína/química , Tecnologia de Alimentos , Microscopia Eletrônica de Transmissão
9.
J Proteomics ; 195: 1-10, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30597314

RESUMO

The RNA-binding protein Hfq protein is a well-characterized post-transcriptional regulator and plays an important role in the regulation of various physiological functions. Most bacterial genomes have only one copy of hfq, but a few bacterial species carry another distinct copy of hfq (hfq2) on the chromosome. However, the physiological properties of Hfq2 remain elusive. Here, we successfully constructed an hfq2 knock-out strain of Aeromonas hydrophila ATCC 7966. Phenotype assays showed that hfq2 deletion significantly increased extracellular protease activity, chemotaxis and swarming motility; increased low temperature, acidic pH, and basic pH resistance; and increased sensitivity to H2O2 stress and high temperatures. A SWATH-based quantitative proteomics method was used to compare the differential expression of proteins between the ∆hfq2 mutant and the wild-type strain. Bioinformatic analysis showed that proteins associated with metabolic pathways were mostly upregulated, while those associated with ribosome subunits were mostly downregulated. Moreover, the deletion of hfq2 leads to the increased expression of several DNA- or RNA-binding regulators, including Hfq and the catabolite gene activator (Crp), and the decreased expression of OmpR. To our knowledge, this is the first study to demonstrate the effects of Hfq2 on physiological function at the protein level. BIOLOGICAL SIGNIFICANCE: Most of bacterial genome has only one hfq copy, while only few bacterial species have two distinct copies in chromosome, and there are few documents about the biological functions of Hfq2. The current phenotype assays showed that Hfq2 plays important roles on bacterial physiological functions such as chemotaxis, swarming motility, ECPase activity and response to various environmental stresses. To better understanding the biological behavior of this protein, a SWATH based quantitative proteomics method was used to compare the altered proteins between ∆hfq2 and wide type strain. Bioinformatics analysis showed that ∆hfq2 significantly affects central metabolic pathway and translation related proteins. Moreover, the deletion of hfq2 lead to the increased expression of post-transcriptional regulator Hfq and catabolite gene activator Crp, and the down regulation of two-component regulatory system regulator OmpR. Our results indicate that Hfq2 is not a pseudogene but plays important roles on the essential physiological functions in A. hydrophila. To our knowledge, this is the first report to demonstrate the molecular function of Hfq2 at proteomics level.

10.
J Proteomics ; 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30521976

RESUMO

Previously, a maltose-specific channel porin, LamB was found to be associate with multi-drug resistance in a lamB deleted strain, but the exact mechanisms require further elucidation. Herein, differential protein expression between the Escherichia coli mutant strain ΔlamB and the wild type strain BW25113, with and without ciprofloxacin (CFLX), was identified using iTRAQ based liquid chromatography-tandem mass spectrometry (LC-MS/MS); while differential metabolite expression was examined using gas chromatography-mass spectrometry (GC-MS). Further Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that lamB deletion leads to a decrease in several key metabolic pathways such as tricarboxylic acid (TCA) cycle, pentose phosphate pathway and glycolysis/gluconeogenesis. When examining the ΔlamB strain without CFLX, many aminoacyl-tRNA biosynthesis and pyrimidine metabolism-related proteins were unaltered, but the addition of CFLX resulted in reduced levels. These findings indicate that a lamB deletion may confer antibiotic resistance by relieving the pressure of protein translation and DNA replication. To further examine antibiotic resistance, exogenous metabolites, including maltose, and several amino acids metabolites were evaluated to determine whether the resistance level could be reduced in the presence of CFLX. The obtained results indicate that lamB knockout may increase bacterial antibiotics resistance by decreasing metabolic pathway activity levels.

11.
Mol Cell Proteomics ; 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30352804

RESUMO

Protein modification by lysine succinylation is a newly identified post-translational modification (PTM) of lysine residues and plays an important role in diverse physiological functions, although their associated biological characteristics are still largely unknown. Here, we investigated the effects of lysine succinylation on the physiological regulation within a well-known fish pathogen, Aeromonas hydrophila. A high affinity purification method was used to enrich peptides with lysine succinylation in A. hydrophilaATCC 7966, and a total of 2,174 lysine succinylation sites were identified on 666 proteins using LC-MS/MS. Gene ontology analysis indicated that these succinylated proteins are involved in diverse metabolic pathways and biological processes, including translation, protein export, and central metabolic pathways. The modifications of several selected candidates were further validated by western blotting. Using site-directed mutagenesis, we observed that the succinylation of lysines on S-ribosylhomocysteine lyase (LuxS) at the K23 and K30 sites positively regulate the production of the quorum sensing autoinducer AI-2, and that these PTMs ultimately alter its competitiveness with another pathogen, Vibrio alginolyticus. Moreover, subsequent metabolomic analyses indicated that K30 succinylation on LuxS may suppress the activated methyl cycle (AMC) and that both the K23 and K30 sites are involved in amino acid metabolism. Taken together, the results from this study provide significant insights into the functions of lysine succinylation and its critical roles on LuxS in regulating the cellular physiology of A. hydrophila.

12.
Fish Shellfish Immunol ; 82: 50-59, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30086377

RESUMO

Iron-related proteins play important roles in iron homeostasis, and they may be potential vaccine candidates against pathogenic Aeromonas hydrophila. In addition, the encapsulation of antigens in single-walled carbon nanotubes (SWCNTs) has recently been shown to effectively stimulate the host immune response. To investigate the immune response of zebrafish to iron-related proteins and SWCNT-encapsulated proteins, we overexpressed and purified four iron-related recombinant proteins (P55870, A0KGK5, A0KPP0, and A0KIY3) from A. hydrophila. We then vaccinated zebrafish with these proteins and their SWCNT-encapsulated counterparts via both intraperitoneal injection and bath immunization. The target proteins evoked an immune response in zebrafish after intraperitoneal injection, and SWCNT-encapsulation significantly increased the immune response after bath immunization. When challenged with virulent A. hydrophila, zebrafish administered 5 µg intraperitoneal injections of SWCNT-P55870, A0KGK5, A0KPP0, or A0KIY3 had remarkably high relative percent survivals (RPSs) (50%, 55.6%, 66.7%, and 94.44% respectively). The RPSs of zebrafish vaccinated via immunization bath with 40 mg/L SWCNT-encapsulated counterparts were also high (52.94%, 55.56%, 61.11%, and 86.11%, respectively). These results indicated that zebrafish vaccinated with P55870, A0KGK5, SWCNT-P55870, and SWCNT-A0KGK5 were partially protected, while A0KPP0 and A0KIY3 were promising vaccine candidates against pathogenic A. hydrophila infection.

13.
Fish Shellfish Immunol ; 68: 1-9, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28676336

RESUMO

The iron-regulated outer membrane protein (OMP) of Aeromonas hydrophila is an effective vaccine candidate, but its intrinsic functional components are largely unknown. In this study, we compared the differentially expressed sarcosine-insoluble fractions of A. hydrophila in iron-limited and normal medium using tandem mass tag labeling-based quantitative proteomics, and identified 91 upregulated proteins including 21 OMPs and 83 downregulated proteins including 10 OMPs. Subsequent bioinformatics analysis showed that iron chelate transport-related proteins were enriched in increasing abundance, whereas oxidoreductase activity and translation-related proteins were significantly enriched in decreasing abundance. The proteomics results were further validated in selected altered proteins by Western blotting. Finally, the vaccine efficacy of five iron-related recombinant OMPs (A0KGW8, A0KFG8, A0KQ46, A0KIU8, and A0KQZ1) that were increased abundance in iron-limited medium, were evaluated when challenged with virulent A. hydrophila against zebrafish, suggesting that these proteins had highly efficient immunoprotectivity. Our results indicate that quantitative proteomics combined with evaluation of vaccine efficacy is an effective strategy for screening novel recombinant antigens for vaccine development.


Assuntos
Aeromonas hydrophila/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas/imunologia , Doenças dos Peixes/prevenção & controle , Regulação Bacteriana da Expressão Gênica , Ferro/metabolismo , Peixe-Zebra , Aeromonas hydrophila/genética , Animais , Proteínas da Membrana Bacteriana Externa/metabolismo , Vacinas Bacterianas/genética , Western Blotting/veterinária , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Proteômica
14.
Neurology ; 88(18): 1727-1735, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28381514

RESUMO

OBJECTIVE: To investigate the prevalence of and personal and professional characteristics associated with burnout, psychological morbidity, job stress, and job satisfaction in Chinese neurologists. METHODS: The China Neurologist Association conducted a national cross-sectional study from September 2014 to March 2015. A questionnaire including the Maslach Burnout Inventory, the 12-item General Health Questionnaire, the Consultants' Mental Health Questionnaire, and questions assessing personal and professional characteristics, career satisfaction, and current doctor-patient relationships was administered. RESULTS: A total of 693 directors of neurology departments and 6,111 neurologists in 30 Chinese provinces returned surveys. Overall, 53.2% of responding neurologists experienced burnout, 37.8% had psychological morbidity, 50.7% had high levels of job stress, 25.7% had low levels of job satisfaction, 76.9% had poor doctor-patient relationships, and 58.1% regretted becoming a doctor. Factors independently associated with burnout were lower income, more hours worked per week, more nights on call per month, working in public hospitals, psychological morbidity, high levels of job stress, low levels of job satisfaction, and poor doctor-patient relationships. Factors independently associated with psychological morbidity included lower income, more nights on call per month, working in enterprise-owned hospitals, burnout, high levels of job stress, and low levels of job satisfaction. CONCLUSIONS: Burnout and psychological morbidity are common in Chinese neurologists. Burnout is the single greatest predictor of neurologists' psychological morbidity, high job stress, and low job satisfaction.


Assuntos
Esgotamento Profissional , Satisfação no Emprego , Neurologistas/psicologia , Estresse Psicológico , Adulto , Esgotamento Profissional/epidemiologia , Escolha da Profissão , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Renda , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Relações Médico-Paciente , Prevalência , Estresse Psicológico/epidemiologia , Inquéritos e Questionários , Carga de Trabalho/psicologia , Adulto Jovem
15.
J Sci Food Agric ; 97(4): 1124-1133, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27283044

RESUMO

BACKGROUND: Timely harvest is critical for hybrid rice to achieve maximum seed viability, vigor and yield. However, how to predict the optimum harvest time has been rarely reported so far. RESULTS: The seed vigor of Zhuliangyou 06 (ZLY06) increased and reached the highest level at 20 days after pollination (DAP), when seed moisture content had a lower value, which was maintained until final seed maturation. For Chunyou 84 (CY84), seed vigor, fresh and dry weight had relatively high values at 25 DAP, when seed moisture content reached the lowest value and changed slightly from 25 to 55 DAP. In both hybrid rice varieties, seed glume chlorophyll content declined rapidly from 10 to 30 DAP and remained at a very low level after 35 DAP. Starch content exhibited an increasing trend during seed maturation, while both soluble sugar content and amylase activity decreased significantly at the early stages of seed development. Moreover, correlation analyses showed that seed dry weight, starch content and superoxide dismutase activity were significantly positively correlated with seed vigor. In contrast, chlorophyll content, moisture content, soluble sugar, soluble protein, abscisic acid, gibberellin content, electrical conductivity, catalase and ascorbate peroxidase activities were significantly negatively correlated with seed vigor. Physiological and biochemical parameters were obviously more closely related with seed vigor than with seed germinability during seed development. CONCLUSION: Seed vigor could be better used as a comprehensive factor to predict the optimum seed harvest time. It is suggested that for ZLY06 seeds could be harvested as early as 20 DAP, whereas for CY84 the earliest optimum harvest time was 25 DAP. © 2016 Society of Chemical Industry.


Assuntos
Agricultura/métodos , Aptidão Genética , Germinação , Hibridização Genética , Oryza/crescimento & desenvolvimento , Melhoramento Vegetal , Sementes/crescimento & desenvolvimento , Ácido Abscísico/metabolismo , Biomassa , Metabolismo dos Carboidratos , Catalase/metabolismo , Clorofila/metabolismo , Giberelinas/metabolismo , Humanos , Vigor Híbrido , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Amido/metabolismo , Superóxido Dismutase/metabolismo
16.
J Sep Sci ; 39(16): 3239-45, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27378629

RESUMO

A simple and highly efficient interface to couple capillary electrophoresis with inductively coupled plasma mass spectrometry by a microflow polyfluoroalkoxy nebulizer and a quadruple ion deflector was developed in this study. By using this interface, six arsenic species, including arsenite, arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, and arsenocholine, were baseline-separated and determined in a single run within 11 min under the optimized separation conditions. The instrumental detection limit was in the range of 0.02-0.06 ng/mL for the six arsenic compounds. Repeatability expressed as the relative standard deviation (n = 5) of both migration time and peak area were better than 2.5 and 4.3% for six arsenic compounds. The proposed method, combined with a closed-vessel microwave-assisted extraction procedure, was successfully applied for the determination of arsenic species in the Solanum Lyratum Thunb samples from Anhui province in China with the relative standard deviations (n = 5) ≤4%, method detection limits of 0.2-0.6 ng As/g and a recovery of 98-104%. The experimental results showed that arsenobetaine was the main speciation of arsenic in the Solanum Lyratum Thunb samples from different provinces in China, with a concentration of 0.42-1.30 µg/g.


Assuntos
Arsenicais/química , Espectrometria de Massas/métodos , Solanum/química , China , Eletroforese Capilar
17.
Environ Sci Pollut Res Int ; 23(19): 19989-20002, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27438877

RESUMO

The present study was carried out to investigate the beneficial impact of seed priming with polyethylene glycol (PEG) under different concentrations of zinc oxide nanoparticles (nano-ZnO), i.e., 0, 250, 500, and 750 mg L(-1) in two cultivars of Oryza sativa (Zhu Liang You 06 and Qian You No. 1). Physiological parameters were improved by priming with 30 % PEG in both cultivars under stress treatments. Seed priming with 30 % PEG improved α-amylase activities and total soluble sugar contents of both cultivars under nano-ZnO stress. In addition, glutathione reductase (GR) activity, reactive oxygen species (ROS) accumulation, and proline contents decreased after the priming treatment in both cultivars under different nano-ZnO concentrations. Expression of GR1, GR2, Amy2A, and Amy3A genes in shoots and roots of both cultivars increased and had higher transcription levels under the nano-ZnO stress condition. Fourier transform infrared spectroscopy (FTIR) analysis did not show any significant effects of the priming treatment on the band observed at 3400, 900, 1600, and 1000 cm(-1) corresponding to alkenyl stretch (C = C), carboxyl acid (O-H), nitrile (C = N), and aromatic (C-H), respectively, in both cultivars under nano-ZnO stress.


Assuntos
Antioxidantes/metabolismo , Nanopartículas/toxicidade , Oryza , Estresse Oxidativo/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Sementes , Óxido de Zinco/toxicidade , Oryza/química , Oryza/efeitos dos fármacos , Oryza/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Sementes/química , Sementes/efeitos dos fármacos , Sementes/metabolismo
18.
Behav Brain Res ; 308: 115-27, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27102340

RESUMO

Major depressive disorder (MDD) is a debilitating illness. However, the underlying molecular mechanisms of depression remain largely unknown. Increasing evidence supports that inflammatory cytokine disturbances may be associated with the pathophysiology of depression in humans. Systemic administration of lipopolysaccharide (LPS) has been used to study inflammation-associated neurobehavioral changes in rodents, but no metabonomic study has been conducted to assess differential metabolites in the prefrontal cortex (PFC) of a LPS-induced mouse model of depression. Here, we employed a gas chromatography-mass spectrometry-based metabonomic approach in the LPS-induced mouse model of depression to investigate any significant metabolic changes in the PFC. Multivariate statistical analysis, including principal component analysis (PCA), partial least squares-discriminate analysis (PLS-DA), and pair-wise orthogonal projections to latent structures discriminant analysis (OPLS-DA), was implemented to identify differential PFC metabolites between LPS-induced depressed mice and healthy controls. A total of 20 differential metabolites were identified. Compared with control mice, LPS-treated mice were characterized by six lower level metabolites and 14 higher level metabolites. These molecular changes were closely related to perturbations in neurotransmitter metabolism, energy metabolism, oxidative stress, and lipid metabolism, which might be evolved in the pathogenesis of MDD. These findings provide insight into the pathophysiological mechanisms underlying MDD and could be of valuable assistance in the clinical diagnosis of MDD.


Assuntos
Depressão/induzido quimicamente , Depressão/patologia , Lipopolissacarídeos , Metaboloma , Córtex Pré-Frontal/metabolismo , Animais , Peso Corporal/fisiologia , Modelos Animais de Doenças , Ingestão de Alimentos/psicologia , Preferências Alimentares/psicologia , Cromatografia Gasosa-Espectrometria de Massas , Elevação dos Membros Posteriores , Masculino , Metabolômica , Camundongos , Camundongos Endogâmicos ICR , Análise de Componente Principal , Natação/psicologia
19.
Int J Mol Sci ; 16(8): 19347-68, 2015 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-26287181

RESUMO

Borna disease virus (BDV) persists in the central nervous systems of a wide variety of vertebrates and causes behavioral disorders. Previous studies have revealed that metabolic perturbations are associated with BDV infection. However, the pathophysiological effects of different viral strains remain largely unknown. Rat cortical neurons infected with human strain BDV Hu-H1, laboratory BDV Strain V, and non-infected control (CON) cells were cultured in vitro. At day 12 post-infection, a gas chromatography coupled with mass spectrometry (GC-MS) metabonomic approach was used to differentiate the metabonomic profiles of 35 independent intracellular samples from Hu-H1-infected cells (n = 12), Strain V-infected cells (n = 12), and CON cells (n = 11). Partial least squares discriminant analysis (PLS-DA) was performed to demonstrate discrimination between the three groups. Further statistical testing determined which individual metabolites displayed significant differences between groups. PLS-DA demonstrated that the whole metabolic pattern enabled statistical discrimination between groups. We identified 31 differential metabolites in the Hu-H1 and CON groups (21 decreased and 10 increased in Hu-H1 relative to CON), 35 differential metabolites in the Strain V and CON groups (30 decreased and 5 increased in Strain V relative to CON), and 21 differential metabolites in the Hu-H1 and Strain V groups (8 decreased and 13 increased in Hu-H1 relative to Strain V). Comparative metabonomic profiling revealed divergent perturbations in key energy and amino acid metabolites between natural strain Hu-H1 and laboratory Strain V of BDV. The two BDV strains differentially alter metabolic pathways of rat cortical neurons in vitro. Their systematic classification provides a valuable template for improved BDV strain definition in future studies.


Assuntos
Doença de Borna/metabolismo , Vírus da Doença de Borna/metabolismo , Encéfalo/virologia , Neurônios/metabolismo , Neurônios/virologia , Ratos/virologia , Animais , Doença de Borna/patologia , Doença de Borna/virologia , Vírus da Doença de Borna/isolamento & purificação , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Metaboloma , Metabolômica , Neurônios/patologia , Ratos/metabolismo , Ratos Sprague-Dawley
20.
J Proteome Res ; 14(8): 3382-9, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26168936

RESUMO

Bipolar disorder (BD) is a complex debilitating mental disorder that is often misdiagnosed as major depressive disorder (MDD). Therefore, a large percentage of BD subjects are incorrectly treated with antidepressants in clinical practice. To address this challenge, objective laboratory-based tests are needed to discriminate BD from MDD patients. Here, a combined gas chromatography-mass spectrometry (GC-MS)-based and nuclear magnetic resonance (NMR) spectroscopic-based metabonomic approach was performed to profile urine samples from 76 MDD and 43 BD subjects (training set) to identify the differential metabolites. Samples from 126 healthy controls were included as metabolic controls. A candidate biomarker panel was identified by further analyzing these differential metabolites. A testing set of, 50 MDD and 28 BD subjects was then used to independently validate the diagnostic efficacy of the identified panel using an area under the receiver operating characteristic curve (AUC). A total of 20 differential metabolites responsible for the discrimination between MDD and BD subjects were identified. A panel consisting of six candidate urinary metabolite biomarkers (propionate, formate, (R*,S*)2,3-dihydroxybutanoic acid, 2,4-dihydroxypyrimidine, phenylalanine, and ß-alanine) was identified. This panel could distinguish BD from MDD subjects with an AUC of 0.913 and 0.896 in the training and testing sets, respectively. These results reveal divergent urinary metabolic phenotypes between MDD and BD. The identified urinary biomarkers can aid in the future development of an objective laboratory-based diagnostic test for distinguishing BD from MDD patients.


Assuntos
Transtorno Bipolar/urina , Transtorno Depressivo Maior/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética/métodos , Metaboloma , Metabolômica/métodos , Adulto , Biomarcadores/metabolismo , Biomarcadores/urina , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/metabolismo , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/metabolismo , Diagnóstico Diferencial , Feminino , Formiatos/urina , Humanos , Hidroxibutiratos/urina , Masculino , Fenilalanina/urina , Propionatos/urina , Pirimidinas/urina , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem , beta-Alanina/urina
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