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1.
Nat Commun ; 12(1): 5243, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34475406

RESUMO

Peroxisome, a special cytoplasmic organelle, possesses one or more kinds of oxidases for hydrogen peroxide (H2O2) production and catalase for H2O2 degradation, which serves as an intracellular H2O2 regulator to degrade toxic peroxides to water. Inspired by this biochemical pathway, we demonstrate the reactive oxygen species (ROS) induced tumor therapy by integrating lactate oxidase (LOx) and catalase (CAT) into Fe3O4 nanoparticle/indocyanine green (ICG) co-loaded hybrid nanogels (designated as FIGs-LC). Based on the O2 redistribution and H2O2 activation by cascading LOx and CAT catalytic metabolic regulation, hydroxyl radical (·OH) and singlet oxygen (1O2) production can be modulated for glutathione (GSH)-activated chemodynamic therapy (CDT) and NIR-triggered photodynamic therapy (PDT), by manipulating the ratio of LOx and CAT to catalyze endogenous lactate to produce H2O2 and further cascade decomposing H2O2 into O2. The regulation reactions of FIGs-LC significantly elevate the intracellular ROS level and cause fatal damage to cancer cells inducing the effective inhibition of tumor growth. Such enzyme complex loaded hybrid nanogel present potential for biomedical ROS regulation, especially for the tumors with different redox state, size, and subcutaneous depth.


Assuntos
Antineoplásicos/farmacologia , Nanogéis/química , Peroxissomos/enzimologia , Fotoquimioterapia/métodos , Animais , Antineoplásicos/química , Catalase/química , Catalase/metabolismo , Catálise , Linhagem Celular Tumoral , Óxido Ferroso-Férrico/química , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Verde de Indocianina/química , Camundongos , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Oxigênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral/efeitos dos fármacos
2.
Planta ; 254(3): 50, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34386845

RESUMO

MAIN CONCLUSION: Overexpression of the leaf color (Lc) gene in Ma bamboo substantially increased the accumulation level of anthocyanin, and improved plant tolerance to cold and drought stresses, probably due to the increased antioxidant capacity. Most bamboos, including Ma bamboo (Dendrocalamus latiflorus Munro), are naturally evergreen and sensitive to cold and drought stresses, while it's nearly impossible to make improvements through conventual breeding due to their long and irregular flowering habit. Moreover, few studies have reported bamboo germplasm innovation through genetic engineering as bamboo genetic transformation remains difficult. In this study, we have upregulated anthocyanin biosynthesis in Ma bamboo, to generate non-green Ma bamboo with increased abiotic stress tolerance. By overexpressing the maize Lc gene, a bHLH transcription activator involved in the anthocyanin biosynthesis in Ma bamboo, we generated purple bamboos with increased anthocyanin levels including cyanidin-3-O-rutinoside, peonidin 3-O-rutinoside, and an unknown cyanidin pentaglycoside derivative. The expression levels of 9 anthocyanin biosynthesis genes were up-regulated. Overexpression of the Lc gene improved the plant tolerance to cold and drought stress, probably due to increased antioxidant capacity. The levels of the cold- and drought-related phytohormone jasmonic acid in the transgenic plants were also enhanced, which may also contribute to the plant stress-tolerant phenotypes. High anthocyanin accumulation level did not affect plant growth. Transcriptomic analysis showed higher expressions of genes involved in the flavonoid pathway in Lc transgenic bamboos compared with those in wild-type ones. The anthocyanin-rich bamboos generated here provide an example of ornamental and multiple agronomic trait improvements by genetic engineering in this important grass species.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Antocianinas , Resposta ao Choque Frio , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo
3.
Plant Physiol Biochem ; 167: 337-348, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34392046

RESUMO

Plants do not always have the genetic capacity to tolerate high levels of arsenic (As), which may not only arrest their growth but pose potential health risks through dietary bioaccumulation. Meanwhile, the interplay between the tomato plants and As-NO-driven molecular cell dynamics is obscure. Accordingly, seedlings were treated with As (10 mg/L) alone or in combination with 100 µM sodium nitroprusside (SNP, NO donor) and 200 µM 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO, NO scavenger). Sodium nitroprusside immobilized As in the roots and reduced the shoot translocation by up-regulating the transcriptional expression of the PCS, GSH1, MT2, and ABC1. SNP further restored the growth retardation through modulating the chlorophyll and proline metabolism, increasing NO accumulation and stomatal conductance along with clear crosstalk between the antioxidant activity as well as glyoxalase I and II leading to endogenous H2O2 and MG reduction. Higher PCs and glutathione accumulation helped protect photosynthetic apparatus; however, cPTIO reversed the protective effects of SNP, confirming the role of NO in the As toxicity alleviation.


Assuntos
Arsênio , Lycopersicon esculentum , Antioxidantes , Arsênio/toxicidade , Peróxido de Hidrogênio , Lycopersicon esculentum/metabolismo , Óxido Nítrico , Nitroprussiato/farmacologia , Oxirredução , Estresse Oxidativo , Fitoquelatinas/metabolismo
4.
IEEE Trans Cybern ; PP2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34460410

RESUMO

In this article, the distributed cooperative control problem of redundant mobile manipulators is investigated. A novel method is proposed to solve the problem by integrating formation control with constrained optimization, which not only transports the object along a reference trajectory in a distributed manner but also obtains the dexterous joint postures and end-effector displacements under safety constraints for collision avoidance. For the constrained optimization, the cost function and safety constraints are designed to quantify the mobility and manipulability of mobile manipulators, and collision-free working ranges with the object and obstacles, respectively. A discontinuous projected primal-dual algorithm with damping terms is proposed to solve the constrained optimization problem, providing the joint postures and end-effector displacements, which minimize the cost function and satisfy safety constraints. For the formation control, a finite-time control law, guided by end-effector displacements from the primal-dual algorithm, is developed in order to transport the object by establishing a prescribed formation and moving its centroid to track the reference trajectory. The cooperative manipulation is therefore achieved by the proposed method, which is further validated through numerical simulations.

5.
J Immunol Res ; 2021: 5523832, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337075

RESUMO

Osteosarcoma is a quickly developing, malignant cancer of the bone, which is associated with a bad prognosis. In osteosarcoma, hypoxia promotes the malignant phenotype, which results in a cascade of immunosuppressive processes, poor prognosis, and a high risk of metastasis. Nonetheless, additional methodologies for the study of hyperoxia in the tumor microenvironment also need more analysis. We obtained 88 children patients with osteosarcoma from the Therapeutically Applicable Research to Generate Effective Treatment (TARGET) database and 53 children patients with RNA sequence and clinicopathological data from the Gene Expression Omnibus (GEO). We developed a four-gene signature related to hypoxia to reflect the immune microenvironment in osteosarcoma that predicts survival. A high-risk score indicated a poor prognosis and immunosuppressive microenvironment. The presence of the four-gene signature related to hypoxia was correlated with clinical and molecular features and was an important prognostic predictor for pediatric osteosarcoma patients. In summary, we established and validated a four-gene signature related to hypoxia to forecast recovery and presented an independent prognostic predictor representing overall immune response strength within the osteosarcoma microenvironment.

6.
World J Biol Psychiatry ; : 1-9, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34320901

RESUMO

AIM: Patients with depression have a high prevalence of developing dyslipidemia. In this study, we aim to investigate the difference of serum lipids, including total cholesterol (TCH), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), between the depressed patients and healthy controls. Sex differences in lipids and their psychological correlations were also included. METHODS: The study included 56 healthy controls (males/females = 26/30) and 110 first-diagnosed drug-naïve outpatients (males/females = 35/75). A total of 42 patients (males/females = 14/28) were followed for 3 months. RESULTS: A significant difference was found in TCH and LDL-C among healthy control and patients. Interestingly, female patients with first-diagnosed, drug-naïve depression had lower atherogenic indices than male patients. After 3 months of antidepressants therapy, female patients exhibited detrimental changes in serum lipids, namely increased TG and atherogenic index. Moreover, correlation analysis showed significant correlations between changes of depression inventory (HAMD and BDI) score and serum lipids (TCH, HDL-C) in depressed patients. CONCLUSION: We found that dyslipidemia was more common in female patients with depression during therapy with antidepressants. Moreover, the altered serum lipids and atherogenic index might be a hallmark of female patients. Further investigation of sex differences in lipid metabolism of depression is warranted.

7.
Stem Cells Dev ; 30(17): 876-889, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34155928

RESUMO

Psoriasis is an autoimmune disease still lacking standard treatment, and it has been demonstrated that mesenchymal stem cells (MSCs) are capable of immunoregulation. The underlying mechanism might involve the secretion of soluble cytokines, such as hepatocyte growth factor (HGF). This study aims to investigate the therapeutic effect of HGF-overexpressed dental pulp stem cells (DPSCs) [DPSCs; HGF overexpressed DPSCs (HGF-DPSCs)] on imiquimod-induced psoriasis. DPSCs were isolated and transfected by adenovirus vector carrying HGF gene (Ad-HGF). The immunoregulatry abilities of DPSCs and HGF-DPSCs were investigated by coculture of the MSCs with peripheral blood mononuclear cells (PBMCs) under appropriated stimulation. The psoriatic mice were treated with saline control, DPSCs, or HGF-DPSCs. Then the mice spleens were collected and weighted. The psoriatic skin lesions were analyzed by Hematoxylin/Eosin and immunohistochemical staining for histopathological changes, and quantitative real-time polymerase chain reaction to detect the expression levels of CD4+ T cell-related transcription factors and cytokines. The mice blood serum was measured by MILLIPLEX analysis and enzyme-linked immunosorbent assay to evaluate the expression levels of inflammation cytokines. The coculture experiments showed HGF overexpression enhanced the immunoregulation abilities of DPSCs not by suppressing PBMCs' proliferation, but by downregulating T helper 1 (Th1), Th17 cells, and upregulating regulatory T (Treg) cells. In psoriatic skin lesions, the psoriasis-like erythema, scaling, and thickening were ameliorated; and the expression of cytokeratin 6 (CK6), and cytokeratin 17 (CK17) were downregulated by DPSCs and HGF-DPSCs treatment. HGF overexpression enhanced the decrease of spleen masses; enhanced the downregulation of the expression levels of interferon-gamma (IFN-γ), tumor necrosis factor-α, and interleukin (IL)-17A in the blood serums; enhanced the downregulation of T-box transcription factor 21 (T-bet), IFN-γ, retinoic acid-related orphan receptor-γt (RORγt), IL-17A, IL-17F, IL-23, and upregulation of Foxp3 and IL-10 in the psoriatic skin lesions. Therefore, HGF overexpression enhanced DPSCs' treatment effect on psoriasis mainly by reducing inflammatory responses. These findings might provide new immunoregulation strategies for psoriasis treatment.

8.
Angew Chem Int Ed Engl ; 60(36): 19982-19987, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34173310

RESUMO

The in situ gelation of injectable precursors is desirable in the field of tissue regeneration, especially in the context of irregular defect filling. The current driving forces for fast gelation include the phase-transition of thermally sensitive copolymers, click chemical reactions with tissue components, and metal coordination effect. However, the rapid formation of tough hydrogels remains a challenge. Inspired by aerobic metabolism, we herein propose a tissue-fluid-triggered cascade enzymatic polymerization process catalyzed by glucose oxidase and ferrous glycinate for the ultrafast gelation of acryloylated chondroitin sulfates and acrylamides. The highly efficient production of carbon radicals and macromolecules contribute to rapid polymerization for soft tissue augmentation in bone defects. The copolymer hydrogel demonstrated the regeneration-promoting capacity of cartilage. As the first example of using artificial enzyme complexes for in situ polymerization, this work offers a biomimetic approach to the design of strength-adjustable hydrogels for bio-implanting and bio-printing applications.

9.
Pharmacol Res Perspect ; 9(3): e00785, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33957018

RESUMO

The aim of this study was to evaluate the tolerability, safety, and pharmacokinetics of single and continuous dose administration of recombinant neorudin (EPR-hirudin, EH) by intravenous administration in healthy subjects, and to provide a safe dosage range for phase II clinical research. Forty-four subjects received EH as a single dose of between 0.2 and 2.0 mg/kg by intravenous bolus and drip infusion. In addition, 18 healthy subjects were randomly divided into three dose groups (0.15, 0.30, and 0.45 mg/kg/h) with 6 subjects in each group for the continuous administration trial. Single or continuous doses of neorudin were generally well tolerated by healthy adult subjects. There were no serious adverse events (SAEs), and all adverse events (AEs) were mild to moderate. Moreover, no subjects withdrew from the trial because of AEs. There were no clinically relevant changes in physical examination results, clinical chemistry, urinalysis, or vital signs. The incidence of adverse events was not significantly related to drug dose or systemic exposure. After single-dose and continuous administration, the serum EH concentration reached its peak at 5 min, and the exposure increased with the increase in the administered dose. The mean half-life (T1/2 ), clearance (Cl), and apparent volume of distribution (Vd) of EH ranged from 1.7 to 2.5 h, 123.9 to 179.7 ml/h/kg, and 402.7 to 615.2 ml/kg, respectively. The demonstrated safety, tolerability, and pharmacokinetic characteristics of EH can be used to guide rational drug dosing and choose therapeutic regimens in subsequent clinical studies. Clinical trial registration: Chinadrugtrials.org identifier: CTR20160444.

10.
Hu Li Za Zhi ; 68(3): 97-107, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34013511

RESUMO

The American Nurses Credentialing Center (ANCC) manages Magnet Recognition Program® certification. Candidates for this certification are required to pass a review comprising six compulsory documents and 84 sets of written documents in five model components as well as an onsite appraisal. The Magnet Recognition Program® for medical institutes is currently regarded as the highest honor in the nursing field. The series of measures necessary to establish a Magnet-recognized hospital is described in this article. Our hospital began preparation for recognition in January 2016, with the application submitted in May 2017. The required measures include establishing a Professional Practice Model, Governance Council, and National Database of Nursing Quality Indicators as well as implementing a mentoring plan. ANCC approved Magnet Recognition Program® recognition for our hospital in May 2020, making ours the first Magnet-recognized hospital in Taiwan. The nursing staff shared their experiences on their Magnet journey. Magnet-recognition demonstrates that a hospital is adequately equipped and trained to provide patients with outstanding nursing care and to operate an excellent nursing practice environment.


Assuntos
Imãs , Recursos Humanos de Enfermagem no Hospital , Credenciamento , Humanos , Taiwan , Estados Unidos
11.
Stem Cell Res Ther ; 12(1): 260, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933140

RESUMO

BACKGROUND: Although increasing evidence has demonstrated that human dental pulp stem cells (hDPSCs) are efficacious for the clinical treatment of skeletal disorders, the underlying mechanisms remain incompletely understood. Osteoarthritis (OA) is one of the most common degenerative disorders in joints and is characterized by gradual and irreversible cartilaginous tissue damage. Notably, immune factors were newly identified to be closely related to OA development. In this study, we explored the modulatory effects of clinical-grade hDPSCs on osteoarthritic macrophages and their protective effects on cartilaginous tissues in OA joints. METHODS: The cell morphology, immunophenotype, and inflammatory factor expression of osteoarthritic macrophages were explored by phase contrast microscope, transmission electron microscopy, immunostaining, flow cytometry, quantitative polymerase chain reaction, and enzyme linked immunosorbent assay, respectively. Additionally, the factors and signaling pathways that suppressed macrophage activation by hDPSCs were determined by enzyme-linked immunosorbent assay and western-blotting. Furthermore, hDPSCs were administered to a rabbit knee OA model via intra-articular injection. Macrophage activation in vivo and cartilaginous tissue damage were also evaluated by pathological analysis. RESULTS: We found that hDPSCs markedly inhibited osteoarthritic macrophage activation in vitro. The cell morphology, immunophenotype, and inflammatory factor expression of osteoarthritic macrophages changed into less inflammatory status in the presence of hDPSCs. Mechanistically, we observed that hDPSC-derived hepatocyte growth factor and transforming growth factor ß1 mediated the suppressive effects on osteoarthritic macrophages. Moreover, phosphorylation of MAPK pathway proteins contributed to osteoarthritic macrophage activation, and hDPSCs suppressed their activation by partially inactivating those pathways. Most importantly, injected hDPSCs inhibited macrophage activation in osteochondral tissues in a rabbit knee OA model in vivo. Further histological analysis showed that hDPSCs alleviated cartilaginous damage to knee joints. CONCLUSIONS: In summary, our findings reveal a novel function for hDPSCs in suppressing osteoarthritic macrophages and suggest that macrophages are efficient cellular targets of hDPSCs for alleviation of cartilaginous damage in OA. hDPSCs treat OA via an osteoarthritic macrophages-dependent mechanisms. hDPSCs suppress the activation of osteoarthritic macrophages in vitro and in vivo and alleviate cartilaginous lesions in OA models.


Assuntos
Polpa Dentária , Osteoartrite , Animais , Diferenciação Celular , Células Cultivadas , Humanos , Macrófagos , Osteoartrite/terapia , Coelhos , Células-Tronco
12.
J Alzheimers Dis ; 81(3): 981-1038, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33896843

RESUMO

BACKGROUND: The toxicity of excessive glutamate release has been implicated in various acute and chronic neurodegenerative conditions. Vesicular glutamate transporters (VGLUTs) are the major mediators for the uptake of glutamate into synaptic vesicles. However, the dynamics and mechanism of this process in glutamatergic neurons are still largely unknown. OBJECTIVE: This study aimed to investigate the candidate protein partners of VGLUT1 and their regulatory roles in the vesicles in rat brain. METHODS: Pull down assay, co-immunoprecipitation assay, or split-ubiquitin membrane yeast two hybrid screening coupled with nanoRPLC-MS/MS were used to identify the candidate protein partners of VGLUT1 in the vesicles in rat brain. The in vitro and in vivo models were used to test effects of AßPP, Atp6ap2, Gja1, and Synataxin on VGLUT1 expression. RESULTS: A total of 255 and 225 proteins and 172 known genes were identified in the pull down assay, co-immunoprecipitation assay, or split-ubiquitin yeast two-hybrid screening respectively. The physiological interactions of SV2A, Syntaxin 12, Gja1, AßPP, and Atp6ap2 to VGLUT1 were further confirmed. Knockdown of Atp6ap2, Gja1, and Synataxin increased VGLUT1 mRNA expression and only knockdown of AßPP increased both mRNA and protein levels of VGLUT1 in PC12 cells. The regulatory function of AßPP on VGLUT1 expression was further confirmed in the in vitro and in vivo models. CONCLUSION: These results elucidate that the AßPP and VGLUT1 interacts at vesicular level and AßPP plays a role in the regulation of VGLUT1 expression which is essential for maintaining vesicular activities.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/metabolismo , Vesículas Sinápticas/metabolismo , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo , Animais , Conexina 43/metabolismo , Ácido Glutâmico/metabolismo , Neurônios/metabolismo , Ligação Proteica , Proteoma , Proteômica , Ratos , Ratos Wistar , Sinapses/metabolismo , Sintaxina 1/metabolismo
13.
Curr Mol Pharmacol ; 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33538683

RESUMO

Most of the tripartite motif (TRIM) family proteins have E3 ubiquitin ligase activities and also have a variety of functions in cellular processes such as intracellular signal transduction, apoptosis, innate immunity and carcinogenesis. TRIM65 is a member of the TRIM family. More and more evidences have shown a unique and importance of TRIM65 protein in the occurrence and development of some diseases. In this review, the importance on TRIM65 in white matter lesions, innate immunity and the effect of tumors was mainly reviewed.

14.
Biomarkers ; 26(2): 95-102, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33401971

RESUMO

OBJECTIVE: To assess the diagnostic value of Trefoil factor 3 (TFF3) and the correlation between TFF3 expression and clinicopathological features in patients with gastric cancer (GC). METHODS: PubMed, The Cochrane, EMbase, and Web of Science were retrieved comprehensively to collect relevant literature. The search ended on 31 May 2020. All data were analyzed using PubMed, The Cochrane, EMbase, and Web of Science were retrieved to collect relevant articles. All data from the included studies were subjected to meta-analysis using Stata 12.0 software. RESULTS: Seventeen studies involved 4654 subjects were included. For the diagnostic value of TFF3 for GC, the sensitivity, specificity, and AUC were 0.71, 0.80, and 0.80, respectively. For the clinicopathological value of TFF3, tissue TFF3 expression showed a higher risk of lymph node metastasis (OR 2.20, 95% CI 1.75-2.78, p < 0.001) and muscularis propria invasion (≥T2) (1.51, 1.13-2.03, p = 0.006), as well as worse TNM stage (2.26, 1.63-3.12, p < 0.001) and histological type (1.72, 1.34-2.20, p < 0.001), while no apparent relationship was found for serous membrane invasion (T4), venous invasion, and peritoneal metastasis. CONCLUSION: TFF3 may be a promising biomarker for GC, and the TFF3 expression is likely to be involved in the invasion, metastasis, and differentiation of GC.

15.
Stem Cell Rev Rep ; 17(2): 318-331, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32749649

RESUMO

Radiation therapy can cause haematopoietic damage, and mesenchymal stem cells (MSCs) derived extracellular vesicles (EVs) have been shown to reverse this damage. Our previous research showed that dental pulp stem cells (DPSCs) have a strong proliferation capacity and can produce abundant amounts of EVs to meet the requirements for use in vitro and in vivo. DPSCs derived EVs (DPSCs-EVs) are evaluated for their effect on reducing haematopoietic damage. Haematopoietic stem cell (HSC) numbers and function were assessed by flow cytometry, peripheral blood cell counts, histology and bone marrow transplantation. Epidermal growth factor (EGF) was used as a reference for evaluating the efficiency of EVs. miRNA microarray was employed to find out the changes of miRNA expression after cells being irradiated in vivo and the role they may play in mitigation the radiation caused injury. We observed the effect of DPSCs-EVs on promoting proliferation and inhibiting apoptosis of human umbilical vein endothelial cells (HUVECs) and FDC-P1 cells in vitro. We found that DPSCs-EVs and EGF could comparably inhibit the decrease in WBC, CFU count and KSL cells in vivo. We also verified that EVs could accelerate the recovery of long-term HSCs. In summary, DPSCs-EVs showed an apoptosis resistant effect on HUVECs and FDC-P1 cells after radiation injury in vitro. EVs from DPSCs were comparable to EGF in their ability to regulate haematopoietic regeneration after radiation injury in vivo. Radiation could alter the expression of some miRNAs in bone marrow cells, and EVs could correct these changes to some extent. Graphical abstract.

16.
Ecotoxicol Environ Saf ; 209: 111793, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33360287

RESUMO

Arsenic (As) toxicity can be a hazardous threat to sustainable agriculture and human health. Piriformospora indica (P. indica), as a beneficial endophytic fungus, is involved in the plant tolerance to stressful conditions. Here, the biochemical and molecular responses of rice plants to As (50 µM) phytotoxicity and P. indica inoculation as well as the role of P. indica in improving rice adaptation to As stress were evaluated. The results showed that As stress reduced chlorophylls content, chlorophyll fluorescence yield (Fv/Fm), electron transport rate (ETR) and growth. However, P. indica restored chlorophyll content and growth. P. indica decreased the contents of methylglyoxal and malondialdehyde by improving the activity of enzymes involved in the glyoxalase pathway and modulating the redox state of the ascorbic acid-glutathione cycle, and consequently, increased the plant tolerance to As toxicity. P. indica, by downregulating Lsi2 expression (involved in As translocation to the shoot) and upregulating PCS1 and PCS2 expression (involved in As sequestration in vacuoles), immobilized As in the roots and reduced damage to photosynthetic organs. P. indica increased iron (Fe) accumulation in the shoot under As toxicity by upregulating the expression of IRO2, YSL2 and FRDL1 genes. The results of the present study augmented our knowledge in using P. indica symbiosis in improving the tolerance of rice plants against As toxicity for sustainable agriculture.


Assuntos
Adaptação Fisiológica/fisiologia , Arsênio/toxicidade , Basidiomycota/fisiologia , Oryza/fisiologia , Poluentes do Solo/toxicidade , Arsênio/metabolismo , Basidiomycota/metabolismo , Clorofila/metabolismo , Humanos , Ferro/metabolismo , Malondialdeído/metabolismo , Oryza/metabolismo , Oryza/microbiologia , Fotossíntese , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Poluentes do Solo/metabolismo , Simbiose
17.
Front Plant Sci ; 11: 560985, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281837

RESUMO

With the development of sequencing technology, the availability of genome data is rapidly increasing, while functional annotation of genes largely lags behind. In Arabidopsis, the functions of nearly half of the proteins are unknown and this remains one of the main challenges in current biological research. In an attempt to identify novel and rapid abiotic stress responsive genes, a number of salt-up (SUP) regulated genes were isolated by analyzing the public transcriptomic data, and one of them, SUPA, was characterized in this study. The expression of SUPA transcripts was rapidly up-regulated by various abiotic stress factors (<15 min), and SUPA protein is mainly localized in the peroxisome. Overexpression of SUPA in Arabidopsis leads to the elevated accumulation of reactive oxygen species (ROS), strong morphological changes and alternations in abiotic stress tolerance. The transcriptome analysis showed changes in expression of genes involved in stress response and plant development. Interestingly, ectopic overexpression of SUPA in poplar leads to a dwarf phenotype with severely curved leaves and changes in the plant tolerance of abiotic stresses. Our study reinforces the potential roles of SUPA in normal plant growth and the abiotic stress response.

18.
Hu Li Za Zhi ; 67(4): 98-105, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32748384

RESUMO

BACKGROUND & PROBLEMS: Poor sleep quality during hospitalization may lead to post-hospital symptoms and increase readmission rates and mortality. Patients in our intensive care unit (ICU) reported low mean scores on the Richards-Campbell Sleep Questionnaire (RCSQ) during their third and fifth days of hospitalization (49.7 mm and 51.7 mm, respectively). Therefore, a project to improve sleep quality in the ICU was established. PURPOSE: To increase the mean RCSQ score from 51.7 mm to 76.0 mm on the fifth day. The fifth day timeframe was chosen because of the disease conditions of the patients and related clinical-medical factors. RESOLUTIONS: The project team proposed an evidence-based, sleep care bundle that included non-medication pain control, environmental regulation, improvement of the care process, and individualized sleep care. RESULTS: After implementing the bundled intervention, the mean RCSQ score of patients in our ICU increased from 49.7 mm to 55.9 mm on the third day and from 51.7 mm to 80.9 mm on the fifth day. CONCLUSIONS: This application of a sleep care bundle effectively improved the factors affecting sleep disturbance and improved quality of sleep in the patients in our intensive care unit.


Assuntos
Unidades de Terapia Intensiva , Pacotes de Assistência ao Paciente/enfermagem , Sono , Humanos , Pesquisa em Avaliação de Enfermagem , Transtornos do Sono-Vigília/prevenção & controle , Inquéritos e Questionários
19.
Commun Biol ; 3(1): 441, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796911

RESUMO

Acetyl coenzyme A (Ac-CoA)-dependent N-acetylation is performed by arylalkylamine N-acetyltransferase (AANAT) and is important in many biofunctions. AANAT catalyzes N-acetylation through an ordered sequential mechanism in which cofactor (Ac-CoA) binds first, with substrate binding afterward. No ternary structure containing AANAT, cofactor, and substrate was determined, meaning the details of substrate binding and product release remain unclear. Here, two ternary complexes of dopamine N-acetyltransferase (Dat) before and after N-acetylation were solved at 1.28 Å and 1.36 Å resolution, respectively. Combined with the structures of Dat in apo form and Ac-CoA bound form, we addressed each stage in the catalytic cycle. Isothermal titration calorimetry (ITC), crystallography, and nuclear magnetic resonance spectroscopy (NMR) were utilized to analyze the product release. Our data revealed that Ac-CoA regulates the conformational properties of Dat to form the catalytic site and substrate binding pocket, while the release of products is facilitated by the binding of new Ac-CoA.


Assuntos
Acetilcoenzima A/metabolismo , Arilalquilamina N-Acetiltransferase/metabolismo , Biocatálise , Insetos/enzimologia , Acetilação , Animais , Arilalquilamina N-Acetiltransferase/química , Monoaminas Biogênicas/química , Monoaminas Biogênicas/metabolismo , Domínio Catalítico , Modelos Moleculares , Conformação Proteica , Relação Estrutura-Atividade , Especificidade por Substrato
20.
J Plant Physiol ; 253: 153267, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32858442

RESUMO

Leaf-vegetable sweetpotato is an important cash crop that is of high nutritional value. Cuttage is the most convenient method for large-scale propagation. However, the rate and number of adventitious roots (ARs) formation vary significantly among different cultivar cuttings. In this study, two varieties, NC1 and FC13-14, were used to compare the rate of ARs formation. The cumulative results of root morphology showed that in NC1 total root length, total root surface area, total root volume, and root tips were 3.7, 3.5, 3.2, and 2.4 times greater, respectively, than those of FC13-14 at 7 d, indicating that the ARs formation and growth were faster in NC1. In addition, the biomass of aboveground and underground parts in NC1 was 3.6 and 1.3 times more, respectively, than that of FC13-14 at 7 d after cutting, suggesting that the rapid ARs formation rate contributed to the growth and yield of stems and leaves. The analysis of plant water potential showed that NC1 exhibiting higher water potential prevented leaf wilting. Gene expression levels of 22 root-related genes revealed differential expression during different developmental periods. Interestingly, YUCCA family genes had elevated transcript abundance at 0, 12, 24, and 36 h. Moreover, analysis of hormones including indole-3-acetic acid (IAA), ethylene (ETH), abscisic acid (ABA), brassinolide (BR), jasmonic acid (JA), gibberellin (GA), and cytokinin (CTK) revealed varied contents during different developmental stages. Cumulative evidence demonstrated that gene expression profiles and hormone content of IAA, ETH, and BR were significantly higher in NC1 roots than in FC13-14 roots following all time periods, while the amount of JA increased and was higher in FC13-14 than in NC1 from 0 to 72 h. This indicates that IAA, BR, and ETH play positive roles and JA has a negative effect on ARs formation. Moreover, ETH takes effect earlier than BR, while IAA and JA have functions throughout the whole process. The findings above were validated by the application of exogenous hormones and hormone synthesis inhibitors. This study reveals the preliminary regulation of ARs formation in leaf-vegetable sweetpotato cuttings and thus contributes to further clarification of the molecular mechanism of multiple hormone interactions.


Assuntos
Ipomoea batatas/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/metabolismo , Ciclopentanos/metabolismo , Citocininas/metabolismo , Etilenos/metabolismo , Giberelinas/metabolismo , Ipomoea batatas/crescimento & desenvolvimento , Oxilipinas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Verduras
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