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1.
Mater Sci Eng C Mater Biol Appl ; 108: 110512, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924017

RESUMO

980-nm-upconverted 530 and 550 nm Er3+ green fluorescence spectra of Er3+/Yb3+-codoped NaGd(WO4)2 submicron crystals were measured in the temperature range of 298-383 K. A sextuple ratiometric thermometry is proposed. It is established on the basis of six schemes of fluorescence intensity ratio (FIR) that considers three component peaks of the 530 nm emission band and two component peaks of the 550 nm emission band, which involve electronic transitions between two Stark sublevels of Er3+. The study shows that the phosphor shows strong green fluorescence, which is verified by measured quantum yield, and thermally stable spectral structure desired for the sextuple ratiometric thermometry. All of the six FIR schemes display highly efficient sensing performances with slightly different thermal sensitivities. Each scheme gives a temperature value and the six schemes give an averaged result. In parallel, we have also carried out an ex vivo experimental study on the temperature characteristics of the green fluorescence of the phosphor. Almost same results have been obtained, verifying biological applicability of the phosphor. The ex vivo experimental results also show that the sextuple thermometry increases considerably the accuracy and reliability of temperature measurement in comparison with the conventional intensity integration method.

2.
Cell Rep ; 29(10): 3223-3234.e6, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31801085

RESUMO

Major depression is a serious global health concern; however, the pathophysiology underlying this condition remains unclear. While numerous studies have focused on brain-specific mechanisms, few have evaluated the role of peripheral organs in depression. Here, we show that the liver activates an intrinsic metabolic pathway that can modulate depressive-like behavior. We find that chronic stress specifically increases the protein levels of monomeric and oligomeric soluble epoxide hydrolase (sEH), a key enzyme in epoxyeicosatrienoic acid (EET) signaling, in the liver. Hepatic deletion of Ephx2 (which encodes sEH) results in antidepressant-like effects, while the hepatic overexpression of sEH induces depressive phenotypes. The activity of sEH in hepatocytes modulates the plasma levels of 14,15-EET, which then interacts with astrocytes in the medial prefrontal cortex to mediate the effects of hepatic Ephx2 deletion. These results suggest that targeting mechanisms underlying the hepatic response to stress would increase our therapeutic options for the treatment of depression.

3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(6): 840-846, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31880115

RESUMO

OBJECTIVE: To investigate the regulatory effect and its mechanism of chrysophanol (CP) on renal injury and immune response in immunoglobin A (IgA) nephropathy rats. METHODS: IgA nephropathy rat model was established by the method of lipopolysaccharide + bovine serum protein + carbon tetrachloride. Then the rats were randomly divided into 5 groups: control group, IgA group, IgA+low, medium and high dose of CP groups(2.5, 5 and 10 mg/kg for each group respectively). IgA+CP groups were intraperitoneally injected with different doses of chrysophanol once a day for 4 weeks, and the control group and IgA group were given isovolumetric saline. Urine protein content, serum creatinine and urea nitrogen were detected at 24 h after the administration of drugs. Kidney histopathological damage and apoptosis were measured by HE and TUNEL staining. The expression levels of Caspase-3 and Caspase-9 were detected by RT-PCR and Western blot; The contents of malondialdehyde (MDA), superoxide dismutase (SOD) and (glutathione peroxidase, Gpx) were detected by enzyme-linked immunosorbent assay (ELISA). The expression of interleukin-1ß, -6 (IL-1ß, IL-6) and tumor necrosis factor (TNF-α) in serum and kidney tissue were measured by ELISA and Western blot, respectively. The mRNA and protein expression levels of toll-like receptro 4 (TLR4), nuclear factor-κB P65 (NF-κB P65) were also detected by RT-PCR and Western blot, and vascular cell adherin molecule (VCAM-1) protein level was deteted by Western blot. RESULTS: In IgA nephropathy rats, the administration of CP reduced proteinuria, serum creatinine and urea nitrogen in a dose-dependent manner (P < 0.01). It also improved the pathological damage of kidney tissue, reduced the apoptosis rate (P < 0.01), and decreased the mRNA and protein expression levels of apoptosis-related proteins Caspase-3 and Caspase-9 (P < 0.01). CP inhibited MDA production while increased the activities of antioxidant enzymes Gpx and SOD (P < 0.01), and decreased the levels of serum and protein expression of IL-1ß, IL-6 and TNF-α (P < 0.01), as well as the expression levels of TLR4, NF-κB P65 and VCAM-1 (P < 0.01). CONCLUSION: Chrysophanol could play a protective role in IgA nephropathy rats, and its mechanism may be related to alleviating kidney injury and regulating immune response.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31715140

RESUMO

OBJECTIVE: To compare participation and subjective experience of participants in both home-based multiuser virtual reality (VR) therapy and home-based single-user (SU) VR therapy. DESIGN: Crossover, randomized trial. SETTING: Initial training and evaluations occurred in a rehabilitation hospital; the interventions took place in participants' homes. PARTICIPANTS: Survivors of stroke with chronic upper extremity impairment (N=20). INTERVENTIONS: Four weeks of in-home treatment using a custom, multiuser virtual reality system (VERGE): 2 weeks of both multiuser (MU) and SU versions of VERGE. The order of presentation of SU and MU versions was randomized such that participants were divided into 2 groups, First MU and First SU. MAIN OUTCOME MEASURES: We measured arm displacement during each session (m) as the primary outcome measure. Secondary outcome measures include time participants spent using each MU and SU VERGE and Intrinsic Motivation Inventory scores. Fugl-Meyer Assessment of Motor Recovery After Stroke Upper Extremity (FMA-UE) score and compliance with prescribed training were also evaluated. Measures were recorded before, midway, and after the treatment. Activity and movement were measured during each training session. RESULTS: Arm displacement during a session was significantly affected the mode of therapy (MU: 414.6m, SU: 327.0m, P=.019). Compliance was very high (99% compliance for MU mode and 89% for SU mode). Within a given session, participants spent significantly more time training in the MU mode than in the SU mode (P=.04). FMA-UE score improved significantly across all participants (Δ3.2, P=.001). CONCLUSIONS: Multiuser VR exercises may provide an effective means of extending clinical therapy into the home.

5.
Sensors (Basel) ; 19(22)2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718098

RESUMO

The vital importance of rapid and accurate detection of food borne pathogens has driven the development of biosensor to prevent food borne illness outbreaks. Electrochemical DNA biosensors offer such merits as rapid response, high sensitivity, low cost, and ease of use. This review covers the following three aspects: food borne pathogens and conventional detection methods, the design and fabrication of electrochemical DNA biosensors and several techniques for improving sensitivity of biosensors. We highlight the main bioreceptors and immobilizing methods on sensing interface, electrochemical techniques, electrochemical indicators, nanotechnology, and nucleic acid-based amplification. Finally, in view of the existing shortcomings of electrochemical DNA biosensors in the field of food borne pathogen detection, we also predict and prospect future research focuses from the following five aspects: specific bioreceptors (improving specificity), nanomaterials (enhancing sensitivity), microfluidic chip technology (realizing automate operation), paper-based biosensors (reducing detection cost), and smartphones or other mobile devices (simplifying signal reading devices).

6.
Nat Chem Biol ; 15(12): 1214-1222, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31591566

RESUMO

Iron is essential for a broad range of biochemical processes in the brain, but the mechanisms of iron metabolism in the brain remain elusive. Here we show that iron functionally translocates among brain regions along specific axonal projections. We identified two pathways for iron transport in the brain: a pathway from ventral hippocampus (vHip) to medial prefrontal cortex (mPFC) to substantia nigra; and a pathway from thalamus (Tha) to amygdala (AMG) to mPFC. While vHip-mPFC transport modulates anxiety-related behaviors, impairment of Tha-AMG-mPFC transport did not. Moreover, vHip-mPFC iron transport is necessary for the behavioral effects of diazepam, a well-known anxiolytic drug. By contrast, genetic or pharmacological promotion of vHip-mPFC transport produced anxiolytic-like effects and restored anxiety-like behaviors induced by repeated restraint stress. Taken together, these findings provide key insights into iron metabolism in the brain and identify the mechanisms underlying iron transport in the brain as a potential target for development of novel anxiety treatments.

7.
Transl Psychiatry ; 9(1): 233, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31534116

RESUMO

Inflammation is a natural defence response of the immune system against environmental insult, stress and injury, but hyper- and hypo-inflammatory responses can trigger diseases. Accumulating evidence suggests that inflammation is involved in multiple psychiatric disorders. Using inflammation-related factors as biomarkers of psychiatric disorders requires the proof of reproducibility and specificity of the changes in different disorders, which remains to be established. We performed a cross-disorder study by systematically evaluating the meta-analysis results of inflammation-related factors in eight major psychiatric disorders, including schizophrenia (SCZ), bipolar disorder (BD), autism spectrum disorder (ASD), major depression disorder (MDD), post-trauma stress disorder (PTSD), sleeping disorder (SD), obsessive-compulsive disorder (OCD) and suicide. A total of 43 meta-analyses involving 704 publications on 44 inflammation-related factors were included in the study. We calculated the effect size and statistical power for every inflammation-related factor in each disorder. Our analyses showed that well-powered case-control studies provided more consistent results than underpowered studies when one factor was meta-analysed by different researchers. After removing underpowered studies, 30 of the 44 inflammation-related factors showed significant alterations in at least one disorder based on well-powered meta-analyses. Eleven of them changed in patients of more than two disorders when compared with the controls. A few inflammation-related factors showed unique changes in specific disorders (e.g., IL-4 increased in BD, decreased in suicide, but had no change in MDD, ASD, PTSD and SCZ). MDD had the largest number of changes while SD has the least. Clustering analysis showed that closely related disorders share similar patterns of inflammatory changes, as genome-wide genetic studies have found. According to the effect size obtained from the meta-analyses, 13 inflammation-related factors would need <50 cases and 50 controls to achieve 80% power to show significant differences (p < 0.0016) between patients and controls. Changes in different states of MDD, SCZ or BD were also observed in various comparisons. Studies comparing first-episode SCZ to controls may have more reproducible findings than those comparing pre- and post-treatment results. Longitudinal, system-wide studies of inflammation regulation that can differentiate trait- and state-specific changes will be needed to establish valuable biomarkers.

8.
JACC Cardiovasc Interv ; 12(12): 1164-1171, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31221307

RESUMO

OBJECTIVES: The authors sought to better understand the stent geometry of the Lotus valve after transcatheter aortic valve replacement (TAVR) and its potential implications for valve size selection. BACKGROUND: The authors hypothesized that the greatest interference between the frame and aortic valvar complex occurs across the aortic valve leaflets. METHODS: The authors retrospectively analyzed the multidetector computed tomography (MDCT) scans of 32 consecutive patients undergoing Lotus valve (Boston Scientific, Natick, Massachusetts) implantation. The prosthesis cross section was analyzed at 3-mm increments along its length. The plane where the frame had the smallest area was defined as the waist. The corresponding plane of the waist on pre-procedural MDCT was identified by surrounding structures such as calcium deposits, commissural fusion, and commissural gaps, and was referred to as the supra-annulus. The spline of the supra-annulus was circumscribed with reference to the post-implant stent geometry at the waist. RESULTS: The waist was 5.8 ± 1.7 mm higher than the native annulus on post-procedural MDCT. The waist had a nearly 2-fold larger compression rate than the stent at the native annulus level (36.3 ± 10.4% vs. 18.9 ± 9.6%; p < 0.01), irrespective of valve morphologies. The supra-annulus was 5.9 ± 1.6 mm higher than the annulus on pre-procedural MDCT. Patients had an approximately 17% decrease in area from the annulus to the supra-annulus (18.3 ± 4.4% for bicuspid morphology and 16.0 ± 3.5% for tricuspid morphology). CONCLUSIONS: Major interference between the implanted prosthesis and anatomy occurred at a level above the annulus. The decrease in area from the annulus to supra-annulus may explain the feasibility of implanting a smaller valve than that suggested by traditional annular measurements.

9.
Plant Physiol ; 180(4): 2240-2253, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31221729

RESUMO

Cellulose synthesis is precisely regulated by internal and external cues, and emerging evidence suggests that light regulates cellulose biosynthesis through specific light receptors. Recently, the blue light receptor CRYPTOCHROME 1 (CRY1) was shown to positively regulate secondary cell wall biosynthesis in Arabidopsis (Arabidopsis thaliana). Here, we characterize the role of FLAVIN-BINDING KELCH REPEAT, F-BOX 1 (FKF1), another blue light receptor and well-known photoperiodic flowering time regulator, in cellulose biosynthesis. A phenotype suppression screen using a cellulose deficient mutant cesa1aegeus,cesa3ixr1-2 (c1,c3), which carries nonlethal point mutations in CELLULOSE SYNTHASE A 1 (CESA1) and CESA3, resulted in identification of the phenotype-restoring large leaf (llf) mutant. Next-generation mapping using the whole genome resequencing method identified the llf locus as FKF1 FKF1 was confirmed as the causal gene through observation of the llf phenotype in an independent triple mutant c1,c3,fkf1-t carrying a FKF1 T-DNA insertion mutant. Moreover, overexpression of FKF1 in llf plants restored the c1,c3 phenotype. The fkf1 mutants showed significant increases in cellulose content and CESA gene expression compared with that in wild-type Columbia-0 plants, suggesting a negative role of FKF1 in cellulose biosynthesis. Using genetic, molecular, and phenocopy and biochemical evidence, we have firmly established the role of FKF1 in regulation of cellulose biosynthesis. In addition, CESA expression analysis showed that diurnal expression patterns of CESAs are FKF1 independent, whereas their circadian expression patterns are FKF1 dependent. Overall, our work establishes a role of FKF1 in the regulation of cell wall biosynthesis in Arabidopsis.

10.
Chemistry ; 25(39): 9174-9179, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31050831

RESUMO

Herein, we report on the use a biohybrid catalyst consisting of palladium nanoparticles immobilized on cross-linked enzyme aggregates of lipase B of Candida antarctica (CalB CLEA) for the dynamic kinetic resolution (DKR) of benzylic amines. A set of amines were demonstrated to undergo an efficient DKR and the recyclability of the catalysts was studied. Extensive efforts to further elucidate the structure of the catalyst are presented.

11.
Phytomedicine ; 61: 152842, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31048127

RESUMO

BACKGROUND: Parkinson's disease (PD) is an age-dependent progressive movement disorder characterized by a profound and selective loss of nigrostriatal dopaminergic neurons. Accumulation of -synuclein (-syn) positive protein aggregates in the substantia nigra is a pathological hallmark of PD, indicating that protein turnover defect is implicated in PD pathogenesis. PURPOSE: This study aims to identify neuroprotective compounds which can alleviate the accumulation of -syn in neuronal cells and dissect the underlying mechanisms. METHODS: High throughput screening was performed by dot blot assay. The degradation of different forms of -syn by candidate compounds were assessed by western blot. The autophagy lysosome pathway and ubiquitin-proteasome system were examined to dissect the degradation pathway. The UPS activity was assessed by cellular UPS substrates degradation assay and biochemical proteasome activity assay. Q-PCR was performed to test the mRNA level of different proteasome subunits. Furthermore, Neuroprotective effect of candidate compound was tested by LDH assay and PI staining. RESULTS: Through the high throughput screening, harmine was identified as a potent -syn lowering compound. The time-dependent and dose-dependent effects of harmine on the degradation of different forms of -syn were further confirmed. Harmine could dramatically promote the degradation of UPS substrates GFP-CL1, Ub-R-GFP and Ub-G76V-GFP, and activate cellular proteasome activity. Mechanistically, harmine dramatically enhanced PKA phosphorylation to enhance proteasome subunit PSMD1 expression. PKA inhibitor blocked the effects of harmine in activating UPS, up regulating PSMD1 and promoting -syn degradation, indicating that harmine enhances UPS function via PKA activation. Moreover, harmine efficiently rescued cell death induced by over-expression of -syn, via UPS-dependent manner. CONCLUSION: Harmine, as a new proteasome enhancer, may have potential to be developed into therapeutic agent against neurodegenerative diseases associated with UPS dysfunction and aberrant proteins accumulation.

12.
Hortic Res ; 6: 48, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31069081

RESUMO

The conserved microRNA396 (miR396) is involved in plant growth, development, and abiotic stress response in multiple plant species through regulating its targets, Growth Regulating Factor (GRF) transcription factor genes. However, the role of miR396 has not yet been characterized in perennial monocot species. In addition, the molecular mechanism of miR396-mediated abiotic stress response remains unclear. To elucidate the role of miR396 in perennial monocot species, we generated transgenic creeping bentgrass (Agrostis stolonifera) overexpressing Osa-miR396c, a rice miRNA396 gene. Transgenic plants exhibited altered development, including less shoot and root biomass, shorter internodes, smaller leaf area, fewer leaf veins, and epidermis cells per unit area than those of WT controls. In addition, transgenics showed enhanced salt tolerance associated with improved water retention, increased chlorophyll content, cell membrane integrity, and Na+ exclusion during high salinity exposure. Four potential targets of miR396 were identified in creeping bentgrass and up-regulated in response to salt stress. RNA-seq analysis indicates that miR396-mediated salt stress tolerance requires the coordination of stress-related functional proteins (antioxidant enzymes and Na+/H+ antiporter) and regulatory proteins (transcription factors and protein kinases). This study establishes a miR396-associated molecular pathway to connect the upstream regulatory and downstream functional elements, and provides insight into the miRNA-mediated regulatory networks.

13.
BMC Complement Altern Med ; 19(1): 109, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31122236

RESUMO

BACKGROUND: Berberine is an isoquinoline alkaloid extracted from various Berberis species which is widely used in East Asia for a wide range of symptoms. Recently, neuroprotective effects of berberine in Alzheimer's disease (AD) animal models are being extensively reported. So far, no clinical trial has been carried out on the neuroprotective effects of berberine. However, a review of the experimental data is needed before choosing berberine as a candidate drug for clinical experiments. We conducted a systematic review on AD rodent models to analyze the drug effects with minimal selection bias. METHODS: Five online literature databases were searched to find publications reporting studies of the effect of berberine treatment on animal models of AD. Up to March 2018, 15 papers were identified to describe the efficacy of berberine. RESULTS: The included 15 articles met our inclusion criteria with different quality ranging from 3 to 5. We analyzed data extracted from full texts with regard to pharmacological effects and potential anti-Alzheimer's properties. Our analysis revealed that in multiple memory defects animal models, berberine showed significant memory-improving activities with multiple mechanisms, such as anti-inflammation, anti-oxidative stress, cholinesterase (ChE) inhibition and anti-amyloid effects. CONCLUSION: AD is likely to be a complex disease driven by multiple factors. Yet, many therapeutic strategies based on lowering ß-amyloid have failed in clinical trials. This suggest that the threapy should not base on a single cause of Alzheimer's disease but rather a number of different pathways that lead to the disease. Overall we think that berberine can be a promising multipotent agent to combat Alzheimer's disease.


Assuntos
Doença de Alzheimer , Berberina , Fármacos Neuroprotetores , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Berberina/química , Berberina/farmacologia , Berberina/uso terapêutico , Modelos Animais de Doenças , Camundongos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos
14.
Front Pharmacol ; 10: 16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30745870

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disorder characterized by the accumulation of protein aggregates (namely Lewy bodies) in dopaminergic neurons in the substantia nigra region of the brain. Alpha-synuclein (α-syn) is the major component of Lewy bodies in PD patients, and impairment of the ubiquitin-proteasome system has been linked to its accumulation. In this work, we developed a tetracycline-inducible expression system, with simultaneous induced expression of α-syn-EGFP and a bright red fluorescent protein marker (mCherry) to screen for potential compounds for degrading α-syn. We identified canthin-6-one as an α-syn lowering compound which promoted both wild type and mutants α-syn degradation in an ubiquitin-proteasome-system (UPS) dependent manner. By CRISPR/Cas9 genome-wide screening technology, we identified RPN2/PSMD1, the 26S proteasome non-ATPase regulatory subunit 1, as the targeting gene for pharmacological activity of canthin-6-one. Finally, we showed that canthin-6-one up-regulates PSMD1 and enhances UPS function by activating PKA.

15.
Exp Clin Endocrinol Diabetes ; 127(1): 50-55, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30396213

RESUMO

OBJECTIVE: To identify correlations of bone mineral density (BMD) and bone metabolism indices with the urine albumin to creatinine ratio (ACR) as an indicator of nephropathy in Chinese patients with type 2 diabetes (T2D). METHODS: In this retrospective analysis, 297 patients with T2D were divided into 3 groups according to the urine ACR. Patients' data were analyzed to identify associations of general conditions, blood glucose level, lipid levels, and uric acid level with BMD and bone metabolism indices. RESULTS: BMD at every location tested (femoral neck, trochanter, inside hip, Ward's triangle, total hip, and lumbar vertebrae) was negatively correlated with the urine ACR (all p<0.05). Osteocalcin, beta-C-terminal telopeptide (ß-CTX), and procollagen type 1 N- peptide (P1NP) were positively correlated with urine ACR (all p<0.05). Finally, 25-hydroxyvitamin D [25(OH)D] was negatively correlated with urine ACR (p<0.05). Multiple regression analysis with adjustment for age, body mass index, disease duration, and other clinical measurements revealed no significant correlation between urine ACR and BMD measurements or ß-CTX (p>0.05). However, significant correlations remained between urine ACR and osteocalcin, P1NP, and 25(OH)D (p<0.05). The same results were obtained for postmenopausal women specifically, with the exception of a significant correlation between the ACR and ß-CTX (p<0.05). CONCLUSION: In the early stage of diabetic nephropathy, BMD changes and bone transformation acceleration may occur, and the acceleration of bone transformation may occur before the change in BMD. Therefore, it is important to monitor bone metabolism indices in the early stage of diabetic nephropathy in T2D patients.


Assuntos
Albuminas/metabolismo , Densidade Óssea , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/metabolismo , Colágeno Tipo I/sangue , Creatinina/urina , Diabetes Mellitus Tipo 2/metabolismo , Neuropatias Diabéticas/metabolismo , Osteocalcina/sangue , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Vitamina D/análogos & derivados , Idoso , Albuminúria/urina , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/urina , China , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/urina , Neuropatias Diabéticas/sangue , Neuropatias Diabéticas/urina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa , Pós-Menopausa/sangue , Estudos Retrospectivos , Vitamina D/sangue
16.
Plant Biotechnol J ; 17(1): 233-251, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29873883

RESUMO

MicroRNA393 (miR393) has been implicated in plant growth, development and multiple stress responses in annual species such as Arabidopsis and rice. However, the role of miR393 in perennial grasses remains unexplored. Creeping bentgrass (Agrostis stolonifera L.) is an environmentally and economically important C3 cool-season perennial turfgrass. Understanding how miR393 functions in this representative turf species would allow the development of novel strategies in genetically engineering grass species for improved abiotic stress tolerance. We have generated and characterized transgenic creeping bentgrass plants overexpressing rice pri-miR393a (Osa-miR393a). We found that Osa-miR393a transgenics had fewer, but longer tillers, enhanced drought stress tolerance associated with reduced stomata density and denser cuticles, improved salt stress tolerance associated with increased uptake of potassium and enhanced heat stress tolerance associated with induced expression of small heat-shock protein in comparison with wild-type controls. We also identified two targets of miR393, AsAFB2 and AsTIR1, whose expression is repressed in transgenics. Taken together, our results revealed the distinctive roles of miR393/target module in plant development and stress responses between creeping bentgrass and other annual species, suggesting that miR393 would be a promising candidate for generating superior crop cultivars with enhanced multiple stress tolerance, thus contributing to agricultural productivity.


Assuntos
Agrostis/metabolismo , MicroRNAs/genética , Agrostis/genética , Agrostis/crescimento & desenvolvimento , Desidratação , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Genes de Plantas/fisiologia , Resposta ao Choque Térmico , MicroRNAs/fisiologia , Oryza/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal , Estresse Fisiológico
17.
Plant Cell Physiol ; 60(2): 285-302, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30351427

RESUMO

Plant organ development to a specific size and shape is controlled by cell proliferation and cell expansion. Here, we identify a novel Myb-like Arabidopsis gene, Development Related Myb-like1 (DRMY1), which controls cell expansion in both vegetative and reproductive organs. DRMY1 is strongly expressed in developing organs and its expression is reduced by ethylene while it is induced by ABA. DRMY1 has a Myb-like DNA-binding domain, which is predominantly localized in the nucleus and does not exhibit transcriptional activation activity. The loss-of-function T-DNA insertion mutant drmy1 shows reduced organ growth and cell expansion, which is associated with changes in the cell wall matrix polysaccharides. Interestingly, overexpression of DRMY1 in Arabidopsis does not lead to enhanced organ growth. Expression of genes involved in cell wall biosynthesis/remodeling, ribosome biogenesis and in ethylene and ABA signaling pathways is changed with the deficiency of DRMY1. Our results suggest that DRMY1 plays an essential role in organ development by regulating cell expansion either directly by affecting cell wall architecture and/or cytoplasmic growth or indirectly through the ethylene and/or ABA signaling pathways.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Sementes/crescimento & desenvolvimento , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/fisiologia , Proteínas de Ligação a DNA/fisiologia , Flores/crescimento & desenvolvimento , Germinação/fisiologia , Filogenia , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Alinhamento de Sequência
18.
Sci Rep ; 8(1): 17530, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30510207

RESUMO

Postsynthetic reactions of metal-organic frameworks (MOFs) are versatile tools for producing functional materials, but the methods of evaluating these reactions are cumbersome and destructive. Here we demonstrate and validate the use of in situ NMR spectroscopy of species in the liquid state to examine solvent-assisted ligand exchange (SALE) and postsynthetic modification (PSM) reactions of metal-organic frameworks. This technique allows functionalization to be monitored over time without decomposing the product for analysis, which simplifies reaction screening. In the case of SALE, both the added ligand and the ligand leaving the framework can be observed. We demonstrate this in situ method by examining SALE and PSM reactions of the robust zirconium MOF UiO-67 as well as SALE with the aluminum MOF DUT-5. In situ NMR spectroscopy provided insights into the reactions studied, and we expect that future studies using this method will permit the examination of a variety of MOF-solute reactions.

19.
Org Lett ; 20(23): 7670-7673, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30451505

RESUMO

The cypemycin decarboxylase CypD is investigated by using a synthetic oligopeptide, which contains the to-be-cyclized dehydroalanine (Dha) residue. It was shown that CypD efficiently catalyzes the decarboxylation of this Dha-containing peptide, but the expected AviCys ring is not formed in the product, suggesting that CypD alone is not enough to form the AviCys ring. It was also shown that the Dha-containing peptide is a better substrate than two similar peptides with a Ser or a Cys residue, supporting that, in cypemycin biosynthesis, Dha formation is prior to decarboxylation of the C-terminal Cys.

20.
Mar Drugs ; 16(10)2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30308963

RESUMO

In this paper, a novel natural influenza A H1N1 virus neuraminidase (NA) inhibitory peptide derived from cod skin hydrolysates was purified and its antiviral mechanism was explored. From the hydrolysates, novel efficient NA-inhibitory peptides were purified by a sequential approach utilizing an ultrafiltration membrane (5000 Da), sephadex G-15 gel column and reverse-phase high-performance liquid chromatography (RP-HPLC). The amino acid sequence of the pure peptide was determined by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) was PGEKGPSGEAGTAGPPGTPGPQGL, with a molecular weight of 2163 Da. The analysis of the Lineweacer⁻Burk model indicated that the peptide was a competitive NA inhibitor with Ki of 0.29 mM and could directly bind free enzymes. In addition, docking studies suggested that hydrogen binding might be the driving force for the binding affinity of PGEKGPSGEAGTAGPPGTPGPQGL to NA. The cytopathic effect reduction assay showed that the peptide PGEKGPSGEAGTAGPPGTPGPQGL protected Madin⁻Darby canine kidney (MDCK) cells from viral infection and reduced the viral production in a dose-dependent manner. The EC50 value was 471 ± 12 µg/mL against H1N1. Time-course analysis showed that PGEKGPSGEAGTAGPPGTPGPQGL inhibited influenza virus in the early stage of the infectious cycle. The virus titers assay indicated that the NA-inhibitory peptide PGEKGPSGEAGTAGPPGTPGPQGL could directly affect the virus toxicity and adsorption by host cells, further proving that the peptide had an anti-viral effect with multiple target sites. The activity of NA-inhibitory peptide was almost inactivated during the simulated in vitro gastrointestinal digestion, suggesting that oral administration is not recommended. The peptide PGEKGPSGEAGTAGPPGTPGPQGL acts as a neuraminidase blocker to inhibit influenza A virus in MDCK cells. Thus, the peptide PGEKGPSGEAGTAGPPGTPGPQGL has potential utility in the treatment of the influenza virus infection.


Assuntos
Antivirais/farmacologia , Gadus morhua/metabolismo , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Neuraminidase/antagonistas & inibidores , Peptídeos/farmacologia , Pele/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Cães , Células Madin Darby de Rim Canino , Peso Molecular , Infecções por Orthomyxoviridae/tratamento farmacológico , Carga Viral/métodos
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