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1.
Food Chem ; 367: 130664, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343804

RESUMO

Cyclodextrin-based dispersive liquid-liquid microextraction (CD-DLLME) was developed for the determination of triazole and strobilurin fungicides in water, juice, and vinegar samples using high-performance liquid chromatography-diode-array detection (HPLC-DAD). Undecanol, which is a green solvent, was selected as the extraction solvent. A cyclodextrin aqueous solution was chosen as the dispersion solvent and demulsifier to avoid the use of a toxic dispersion solvent and eliminate the centrifugation step. Dispersion and phase separation were completed within 1 and 60 s, respectively. The linear range of this method was 1 to 100 µg L-1. The limits of detection were 0.3 µg L-1 along with the preconcentration factor of 133 and enrichment factor of 124. The recovery was 83.2% to 103.2%. This pretreatment method was fast, simple, and environmentally friendly and was successfully applied to the analysis of triazole and strobilurin fungicide residues in water, juice, and vinegar samples.


Assuntos
Ciclodextrinas , Fungicidas Industriais , Microextração em Fase Líquida , Poluentes Químicos da Água , Ácido Acético , Cromatografia Líquida de Alta Pressão , Fungicidas Industriais/análise , Solventes , Água , Poluentes Químicos da Água/análise
2.
Oxid Med Cell Longev ; 2021: 5093216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650663

RESUMO

Ischemia-reperfusion (I/R) injury often occurred in some pathologies and surgeries. I/R injury not only harmed to physiological functions of corresponding organ and tissue but also induced multiple tissue or organ dysfunctions (even these in distant locations). Although the reperfusion of blood attenuated I/R injury to a certain degree, the risk of secondary damages was difficult to be controlled and it even caused failures of these tissues and organs. Lipoic acid (LA), as an endogenous active substance and a functional agent in food, owns better safety and effects in our body (e.g., enhancing antioxidant activity, improving cognition and dementia, controlling weight, and preventing multiple sclerosis, diabetes complication, and cancer). The literature searching was conducted in PubMed, Embase, Cochrane Library, Web of Science, and SCOPUS from inception to 20 May 2021. It had showed that endogenous LA was exhausted in the process of I/R, which further aggravated I/R injury. Thus, supplements with LA timely (especially pretreatments) may be the prospective way to prevent I/R injury. Recently, studies had demonstrated that LA supplements significantly attenuated I/R injuries of many organs, though clinic investigations were short at present. Hence, it was urgent to summarize these progresses about the effects of LA on different I/R organs as well as the potential mechanisms, which would enlighten further investigations and prepare for clinic applications in the future.

3.
Child Adolesc Psychiatry Ment Health ; 15(1): 60, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34654451

RESUMO

BACKGROUND: Mobile phone addiction has become a social problem that affects the healthy growth of adolescents, and it may be correlated with coping style. The aim of this study was to investigate the relationship between mobile phone addiction and coping style and the influencing factors for adolescents. METHODS: A meta-analysis was conducted by searching China National Knowledge Infrastructure (CNKI), WANFANG DATA and Chongqing VIP Information Co., Ltd. (VIP), PubMed, Web of Science, Embase, and PsycINFO. Stata 16.0 was used to analyse the overall effect and test the moderating effect. RESULTS: Thirty-three studies were included, involving a total of 20,349 subjects. There was no significant correlation between adolescents' mobile phone addiction and positive coping style (r = - 0.02, 95% CI = - 0.06 to 0.02, P > 0.05), but there was a moderate positive correlation between adolescents' mobile phone addiction and negative coping style (r = 0.31, 95% CI = 0.26 to 0.36, P < 0.001). The moderating effect analysis showed that the effect of dissertations on mobile phone addiction and positive coping style among adolescents was significantly larger than that of journal articles. The Smartphone Addiction Scale for College Students (SAS-C) showed the largest effect on mobile phone addiction and positive coping style among adolescents. The time of publication significantly positively moderated the relationship between mobile phone addiction and negative coping style among adolescents. The Simplified Coping Style Questionnaire (SCSQ) showed the largest effect on adolescents' mobile phone addiction and negative coping style. However, the correlation between adolescents' mobile phone addiction and coping style was not affected by age or gender. CONCLUSIONS: There was a close relationship between mobile phone addiction and coping style among adolescents. In the future, longitudinal research should be carried out to better investigate the dynamic changes in the relationship between mobile phone addiction and coping style.

4.
Psychiatry Res ; 306: 114219, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34614443

RESUMO

This study aimed to examine the effects of different types of bullying victimization (direct, relational, and cyber) on psychological symptoms, self-harm, and suicidality (including suicidal ideation and attempts) among adolescents, and to explore whether these effects may vary by gender. The data were obtained from a cross-sectional study of adolescents (n = 11,248, 46.7% females) with a mean age of 13.83 years from grade 5 to 12 in Henan, China. A series of binary logistic regression models were conducted to estimate the associations between different types of bullying victimization and psychological symptoms, self-harm, suicidal ideation, and suicidal attempts, after adjusting for demographic covariates. All three types of bullying victimization were significantly associated with psychological symptoms, self-harm, suicidal ideation, and suicidal attempts. Adolescents who suffered from cyberbullying victimization were more likely to commit self-harm and suicidal attempts as compared to direct and relational victimization. Female adolescents who suffered from relational bullying tend to have a higher risk of suicidal attempts than male adolescents. The current study demonstrated the negative effect of bullying victimization on adolescents' adverse psychological outcomes and gender difference need to be taken into account in developing targeted intervention strategies to address bullying victimization.

5.
Nanoscale ; 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34613321

RESUMO

Coupled with renewable electricity, electrochemical reduction of CO2 (CO2RR) is one of the sustainable strategies for the production of value-added carbon-containing chemicals. Cu-based catalysts are by far the most widely studied electrocatalytic materials for CO2RR, although they exhibit poor performance in CO selectivity. In this work, we have designed a Cu1.96S/Cu tandem structure via a combined electrospinning and calcination method. The catalyst enables CO2 reduction to CO with high selectivity >80% with a production rate of 34.6 µmol h-1 cm-2 at -0.68 V vs. RHE, which is superior to most of the Cu-based catalysts under the same operation conditions. Theoretical simulations show that the improved CO2RR performance stems from the Cu1.96S/Cu tandem structure in which Cu acts as a *CO-producing site and the neighboring Cu1.96S facilitates the following *CO desorption step. This work opens new possibilities for exploiting tandem catalysis mechanisms.

6.
J Environ Manage ; 301: 113848, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34597950

RESUMO

Biodegradation could be a potential alternative solution to polyethylene (PE) pollution. However, its hydrophobic surface and long carbon chains make extremely low biodegradation efficiency. In this study, we screened a novel potential bacterial strain C5 (CGMCC number: 1.18715) for low-density polyethylene (LDPE) biodegrading from landfills. The strain was identified as Bacillus velezensis according to its 16S rRNA sequence. The contact angle analysis indicated that C5 could rapidly form biofilm on untreated LDPE which resulted in contact angles decreasing from 100° to 54° over 7 d. After the LDPE film incubated with C5 for 90 d, the thickness and weight of LDPE film decreased by 26% and 8.01%, respectively. Besides, the biotreated PE film was found with increases in weight-averaged molecular weight by 29.8%, suggesting low molar mass chains were consumed. C24-C29 n-alkanes were detected in the biodegradation products, which proved the depolymerization of LDPE. Combined with the genome mining results, a possible biofilm-aided degrading mechanism was proposed and might involve key enzymes, such as laccase, cytochrome P450 and propionyl-CoA carboxylase, which could constitute a multienzyme system for the co-catalytic degradation of LDPE waste.

7.
Cell Commun Signal ; 19(1): 93, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521440

RESUMO

BACKGROUND: Exosomes mediated crosstalk between tumor cells and other stromal cells including tumor associated macrophages plays an essential role in reprogramming tumor microenvironment (TME) to facilitate tumor progression. However, the mechanism of tumor derived exosomes promotes bladder cancer progression have not been defined. METHODS: Exosomes were extracted from bladder cancer cells MB49 conditioned medium by ultracentrifugation. The effects of MB49-derived exosomes on macrophages polarization were analyzed by qPCR, flow cytometry, and Western blot. The immunosuppressive phenotype and function of MB49-derived exosomes stimulated macrophages were verified by tumor xenograft assays and T cell co-culture experiments. Exosomal miRNAs were analyzed by microarray to identify potential targets regulating macrophage polarization. RESULTS: MB49-derived exosomes could be ingested by macrophages, consequently promoting macrophages immunosuppressive polarization. Mechanically, the MB49-derived exosomes induced macrophage M2 polarization was mediated by down-regulation of PTEN and activation of AKT/STAT3/6 signaling. Moreover, hindrance of the generation or secretion of exosomes by GW4869 inhibited macrophages differentiation into immunosuppressive phenotype and function, thereby suppressed tumor growth in a mouse subcutaneous tumor model. CONCLUSION: Our study confirmed the contribution of bladder cancer derived exosomes on the establishment of immunosuppressive TME and provided a potential therapeutic target for bladder cancer treatment. Video Abstract.

8.
J Hazard Mater ; 423(Pt A): 126962, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34464866

RESUMO

Colorimetric and fluorescent methods for Ochratoxin A (OTA) detection are convenient and well received. However, the pigments and autofluorescence originated from food matrices often interfere with detection signals. We have developed a strategy with colorimetric and fluorescent dual modes to solve this challenge. In the colorimetric mode, OTA aptamer (AP9) was assembled into a DNA triple-helix switch with a specially designed signal-amplifying sequence. The OTA-induced G-quadruplex (G4) of AP9 would open the switch and release the signal-amplifying sequence for colorimetric signal amplification. The G4 structures of AP9 were further utilized to combine with the fluorogenic dye ThT for fluorescent mode. By skillfully engineering DNA G4 assembly for signal amplification, there was no need for any DNA amplification or nanomaterials labeling. Detections could be carried out in a wide temperature range (22-37 â„ƒ) and finished rapidly (colorimetric mode, 60 min; fluorescent mode, 15 min). Broad linear ranges (colorimetric mode, 10-1.5 ×103 µg/kg; fluorescent mode, 0.05-1.0 ×103 µg/kg) were achieved. The limit of detection for colorimetric and fluorescent modes were 4 µg/kg and 0.01 µg/kg, respectively. The two modes have been successfully applied to detect OTA in samples with intrinsic pigments and autofluorescence, showing their applicability and reliability.

9.
J Colloid Interface Sci ; 606(Pt 1): 158-166, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34388568

RESUMO

Sulfonated polydivinylbenzene bamboo-like nanotube (SPDVB) with effective olefins oxidation activity is prepared by combining cationic polymerization and sulfonation. By merely adjusting sulfonation time, SPDVB with different sulfonic acid group (-SO3H) contents is achieved. SPDVB is used as both a solid emulsifier and catalyst to fabricate Pickering emulsion interface catalytic system for oxidizing olefins with 30% H2O2 acting as oxidant/water phase and olefins acting as reactants/oil phase. It is shown that Pickering emulsion interface catalytic system stabilized by SPDVB exhibits enhanced olefins oxidation efficiency than the conventional ones. At the optimum catalyst and reaction condition, the conversion of olefins by Pickering emulsion interface catalytic system stabilized by SPDVB for cyclohexene, 1-methylcyclohexene, cyclooctene, 2,3-dimethyl-2-butene oxidation is higher than 90.00% and the corresponding 1,2-diol selectivity exceeds 93.00% except the selectivity to 1-methyl-1,2-cyclohexanediol. The catalytic system also exhibits excellent cycling performance (>95.00% olefins conversion and >89.00% 1,2-diol selectivity for cyclohexene/2,3-dimethyl-2-butene oxidation after four cycles). A possible mechanism for oxidation of olefins to 1,2-diol by SPDVB stabilized Pickering emulsion is proposed: the high catalytic interface area between sulfonic acid group and H2O2 in water phase enhances the sulfonic acid group of SPDVB to convert into peroxysulfonic acid (catalytic activity centre) firstly; then the formed peroxysulfonic acid attacks the double bond of olefins to form epoxide intermediates, which will be hydrolyzed to 1,2-diol.

10.
Front Cell Infect Microbiol ; 11: 577236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307184

RESUMO

Gut microbiota is regarded as the second human genome and forgotten organ, which is symbiotic with the human host and cannot live and exist alone. The gut microbiota performs multiple physiological functions and plays a pivotal role in host health and intestinal homeostasis. However, the gut microbiota can always be affected by various factors and among them, it is radiotherapy that results in gut microbiota dysbiosis and it is often embodied in a decrease in the abundance and diversity of gut microbiota, an increase in harmful bacteria and a decrease in beneficial bacteria, thereby affecting many disease states, especially intestine diseases. Furthermore, gut microbiota can produce a variety of metabolites, among which short-chain fatty acids (SCFAs) are one of the most abundant and important metabolites. More importantly, SCFAs can be identified as second messengers to promote signal transduction and affect the occurrence and development of diseases. Radiotherapy can lead to the alterations of SCFAs-producing bacteria and cause changes in SCFAs, which is associated with a variety of diseases such as radiation-induced intestinal injury. However, the specific mechanism of its occurrence is not yet clear. Therefore, this review intends to emphasize the alterations of gut microbiota after radiotherapy and highlight the alterations of SCFAs-producing bacteria and SCFAs to explore the mechanisms of radiation-induced intestinal injury from the perspective of gut microbiota and its metabolite SCFAs.


Assuntos
Microbioma Gastrointestinal , Bactérias , Disbiose , Ácidos Graxos Voláteis , Humanos , Intestinos
12.
J Agric Food Chem ; 69(29): 8130-8143, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34269571

RESUMO

A tumor-related hypoxic microenvironment can promote the proliferation of gastric cancer cells, and hypoxic-induced autophagy is the main mechanism of protection against hypoxia in gastric cancer cells. Isorhamnetin (ISO) is a chemical substance derived from plants, mainly from the sea buckthorn. Previous studies have shown that ISO has antitumor effects, but the effects of ISO against gastric cancer in a hypoxic environment are still unknown. In this study, we investigated the effects of ISO against gastric cancer in a hypoxic environment and the mechanisms underlying ISO-induced gastric cancer cell death. The results show that ISO targeted PI3K and blocked the PI3K-AKT-mTOR signaling pathway, significantly inhibiting gastric cancer cell autophagy in a hypoxic environment, inhibiting cell proliferation, decreasing mitochondrial membrane potential, and promoting mitochondria-mediated apoptosis. ISO, a functional food component, is a promising candidate for the treatment of gastric cancer.


Assuntos
Neoplasias Gástricas , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Hipóxia , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Quercetina/análogos & derivados , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Microambiente Tumoral
13.
Biol Trace Elem Res ; 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34287812

RESUMO

Arsenic (As) pollution is ubiquitous in water, which shows immunotoxicity to aquatic organisms. As an indispensable regulator of gene transcription and enzymatic modification, zinc (Zn) may play a preventive and therapeutic effect on As toxicity. The purpose of this study was to investigate the interactions of As and Zn on the head kidney of common carp Cyprinus carpio. Herein the carp were treated alone or in combination with waterborne As3+ (2.83 mg/L) and/or Zn2+ (1 mg/L). Results suggested a head kidney-toxic effect of As exposure, which was manifested by the histopathological damage of the head kidney, elevation of nuclear translocation of pro-inflammatory nuclear factor-kappa light chain enhancer of B cells (NF-κB), and blockage of the anti-oxidative nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. The global activation of three endoplasmic reticulum (ER) stress pathways led to the execution of programmed cell death, including ER apoptosis mediated by C/EBP-homologous protein (CHOP), death receptor-mediated exogenous cell apoptosis, and the endogenous apoptosis executed by Caspases9. The combined application of Zn can significantly improve the histopathological damage of the head kidney, the imbalance of the antioxidant system, and the apoptosis outcomes due to ER stress. In conclusion, this study indicates that Zn has an antagonistic effect on the head kidney injury of common carp induced by sub-chronic As exposure. The results of this study provide basic data for the risk assessment of As accumulation in an aquatic environment and a reference for the use of Zn preparation in aquaculture.

14.
Signal Transduct Target Ther ; 6(1): 289, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326311

RESUMO

Pregnant women are generally more susceptible to viral infection. Although the impact of SARS-CoV-2 in pregnancy remains to be determined, evidence indicates that the risk factors for severe COVID-19 are similar in pregnancy to the general population. Here we systemically analyzed the clinical characteristics of pregnant and non-pregnant female COVID-19 patients who were hospitalized during the same period and found that pregnant patients developed marked lymphopenia and higher inflammation evident by higher C-reactive protein and IL-6. To elucidate the pathways that might contribute to immunopathology or protective immunity against COVID-19 during pregnancy, we applied single-cell mRNA sequencing to profile peripheral blood mononuclear cells from four pregnant and six non-pregnant female patients after recovery along with four pregnant and three non-pregnant healthy donors. We found normal clonal expansion of T cells in the pregnant patients, heightened activation and chemotaxis in NK, NKT, and MAIT cells, and differential interferon responses in the monocyte compartment. Our data present a unique feature in both innate and adaptive immune responses in pregnant patients recovered from COVID-19.


Assuntos
Imunidade Adaptativa , COVID-19/imunologia , Imunidade Inata , Linfócitos/imunologia , Complicações Infecciosas na Gravidez/imunologia , SARS-CoV-2/imunologia , Adulto , Proteína C-Reativa/imunologia , Feminino , Humanos , Interleucina-6/imunologia , Gravidez , Estudos Retrospectivos , Análise de Sequência de RNA , Análise de Célula Única
15.
Sci Rep ; 11(1): 15180, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34312446

RESUMO

Kv1.1 containing potassium channels play crucial roles towards dampening neuronal excitability. Mice lacking Kv1.1 subunits (Kcna1-/-) display recurrent spontaneous seizures and often exhibit sudden unexpected death. Seizures in Kcna1-/- mice resemble those in well-characterized models of temporal lobe epilepsy known to involve limbic brain regions and spontaneous seizures result in enhanced cFos expression and neuronal death in the amygdala. Yet, the functional alterations leading to amygdala hyperexcitability have not been identified. In this study, we used Kcna1-/- mice to examine the contributions of Kv1.1 subunits to excitability in neuronal subtypes from basolateral (BLA) and central lateral (CeL) amygdala known to exhibit distinct firing patterns. We also analyzed synaptic transmission properties in an amygdala local circuit predicted to be involved in epilepsy-related comorbidities. Our data implicate Kv1.1 subunits in controlling spontaneous excitatory synaptic activity in BLA pyramidal neurons. In the CeL, Kv1.1 loss enhances intrinsic excitability and impairs inhibitory synaptic transmission, notably resulting in dysfunction of feed-forward inhibition, a critical mechanism for controlling spike timing. Overall, we find inhibitory control of CeL interneurons is reduced in Kcna1-/- mice suggesting that basal inhibitory network functioning is less able to prevent recurrent hyperexcitation related to seizures.

16.
Dis Markers ; 2021: 6680883, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211612

RESUMO

Background: Glioma is the most common primary intracranial tumor and is associated with poor prognosis. Identifying effective biomarkers for glioma is particularly important. MXRA5, a secreted glycoprotein, is involved in cell adhesion and extracellular matrix remodeling and has been reported to be expressed in many cancers. However, the role and mechanism of action of MXRA5 in gliomas remain unclear. This study was aimed at investigating the role of MXRA5 at the transcriptome level and its clinical prognostic value. Methods: In this study, RNA microarray data of 301 glioma patients from the Chinese Glioma Genome Atlas (CGGA) were collected as a training cohort and RNA-seq data of 702 glioma samples from The Cancer Genome Atlas (TCGA) were used for validation. We analyzed the clinical and molecular characteristics as well as the prognostic value of MXRA5 in glioma. In addition, the expression level of MXRA was evaluated in 28 glioma tissue samples. Results: We found that MXRA5 expression was significantly upregulated in high-grade gliomas and IDH wild-type gliomas compared to controls. Receiver operating characteristic (ROC) analysis showed that MXRA5 is a potential marker of the mesenchymal subtype of glioblastoma multiforme (GBM). We found that MXRA5 expression is highly correlated with immune checkpoint molecule expression levels and tumor-associated macrophage infiltration. High MXRA5 expression could be used as an independent indicator of poor prognosis in glioma patients. Conclusion: Our study suggests that MXRA5 expression is associated with the clinicopathologic features and poor prognosis of gliomas. MXRA5 may play an important role in the immunosuppressive microenvironment of glioma. As a secreted glycoprotein, MXRA5 is a potential circulating biomarker for glioma, deserving further investigation.

17.
Nanoscale ; 13(26): 11360-11369, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34096562

RESUMO

Emulating the biological behavior of the human brain with artificial neuromorphic devices is essential for the future development of human-machine interactive systems, bionic sensing systems and intelligent robotic systems. In this paper, artificial flexible transparent carbon nanotube synaptic transistors (F-CNT-STs) with signal transmission and emotional learning functions are realized by adopting the poly(vinyl alcohol) (PVA)/SiO2 proton-conducting electrolyte. Synaptic functions of biological synapses including excitatory and inhibitory behaviors are successfully emulated in the F-CNT-STs. Besides, synaptic plasticity such as spike-duration-dependent plasticity, spike-number-dependent plasticity, spike-amplitude-dependent plasticity, paired-pulse facilitation, short-term plasticity, and long-term plasticity have all been systematically characterized. Moreover, the F-CNT-STs also closely imitate the behavior of human brain learning and emotional memory functions. After 1000 bending cycles at a radius of 3 mm, both the transistor characteristics and the synaptic functions can still be implemented correctly, showing outstanding mechanical capability. The realized F-CNT-STs possess low operating voltage, quick response, and ultra-low power consumption, indicating their high potential to work in low-power biological systems and artificial intelligence systems. The flexible artificial synaptic transistor enables its potential to be generally applicable to various flexible wearable biological and intelligent applications.


Assuntos
Nanotubos de Carbono , Inteligência Artificial , Humanos , Dióxido de Silício , Sinapses , Transistores Eletrônicos
18.
Tree Physiol ; 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34185092

RESUMO

Low temperature is a major stress that severely affects plant growth and development. ICE1 (Inducer of CBF Expression 1) plays a key role in plant cold tolerance by regulating the expression of cold stress-responsive genes. In the present study, we characterized the function and underlying regulatory mechanism of PsnICE1 from Xiaohei poplar (Populus simonii × P. nigra). PsnICE1 was significantly induced in response to cold stress in the roots, stems and leaves. PsnICE1 proteins were found to localize to the nucleus and exert transactivation activity via thier N-terminal transactivation domain. Compared with non-transgenic poplar, transgenic poplar overexpressing PsnICE1 showed substantially enhanced tolerance to cold stress, with higher survival rates and antioxidant enzyme activity levels and reduced reactive oxygen species (ROS) accumulation. In contrast, plants with RNA inhibition-mediated silencing of PsnICE1 showed the opposite phenotype. PsnICE1 can bind to H-box and ABRE elements, and more importantly, it mainly binds to IBS1 (a newly discovered cis-acting element) and E-box elements to regulate stress-related genes involved in ROS scavenging. Overall, these results indicated that PsnICE1 functions as a positive regulator of cold tolerance and serves as a potential candidate gene for plant cold tolerance improvement via molecular breeding.

19.
BMC Plant Biol ; 21(1): 291, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34167462

RESUMO

Brassinosteroids (BRs) play important roles in plant growth and development. Although BR receptors have been intensively studied in Arabidopsis, those in foxtail millet remain largely unknown. Here, we show that the BR signaling function of BRASSINOSTEROID INSENSITIVE 1 (BRI1) is conserved between Arabidopsis and foxtail millet, a new model species for C4 and Panicoideae grasses. We identified four putative BR receptor genes in the foxtail millet genome: SiBRI1, SiBRI1-LIKE RECEPTOR KINASE 1 (SiBRL1), SiBRL2 and SiBRL3. Phylogenetic analysis was used to classify the BR receptors in dicots and monocots into three branches. Analysis of their expression patterns by quantitative real-time PCR (qRT-PCR) showed that these receptors were ubiquitously expressed in leaves, stems, dark-grown seedlings, roots and non-flowering spikelets. GFP fusion experiments verified that SiBRI1 localized to the cell membrane. We also explored the SiBRI1 function in Arabidopsis through complementation experiments. Ectopic overexpression of SiBRI1 in an Arabidopsis BR receptor loss-of-function mutant, bri1-116, mostly reversed the developmental defects of the mutant. When SiBRI1 was overexpressed in foxtail millet, the plants showed a drooping leaf phenotype and root development inhibition, lateral root initiation inhibition, and the expression of BR synthesis genes was inhibited. We further identified BRI1-interacting proteins by immunoprecipitation (IP)-mass spectrometry (MS). Our results not only demonstrate that SiBRI1 plays a conserved role in BR signaling in foxtail millet but also provide insight into the molecular mechanism of SiBRI1.


Assuntos
Brassinosteroides/metabolismo , Genes de Plantas/genética , Proteínas de Plantas/genética , Receptores de Superfície Celular/genética , Setaria (Planta)/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiologia , Evolução Molecular , Filogenia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Proteínas Quinases/genética , Proteínas Quinases/fisiologia , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/fisiologia , Setaria (Planta)/metabolismo
20.
Food Funct ; 12(15): 6712-6724, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34160501

RESUMO

Branched chain amino acids (BCAA), especially leucine (Leu), have been reported to decrease fat deposition. However, opposite effects of BCAA on lipid metabolism have been observed. To determine the role of BCAA in lipid metabolism, an amino acid-defined diet was formulated and C57BL/6J mice were assigned into the following groups: amino acid-defined control diet and control diet supplemented with Leu, isoleucine, or valine. Nitrogen was balanced by proportionally mixed amino acids except BCAA. Results showed that dietary Leu supplementation significantly increased the levels of serum triglycerides, total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol and urea nitrogen. Metabolomics showed that biosynthesis of unsaturated fatty acids was altered by Leu supplementation. Leu treatment up-regulated the expression of genes related to fat synthesis and down-regulated the expression of genes related to fatty acid synthesis. Furthermore, the genes and proteins of selective markers involved in browning of white adipose tissue (WAT) were up-regulated by dietary supplementation with Leu. This study indicated that dietary supplementation with Leu, but not isoleucine or valine, significantly affected lipid metabolism by regulating lipid metabolism-related genes and serum fatty acid concentration, providing a new tool in the management of obesity and metabolic disorders.

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