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1.
Cell Mol Neurobiol ; 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32140899

RESUMO

Recent studies demonstrated that FoxO3 circular RNA (circFoxO3) plays an important regulatory role in tumourigenesis and cardiomyopathy. However, the role of circFoxO3 in neurodegenerative diseases remains unknown. The aim of this study was to examine the possible role of circFoxO3 in neurodegenerative diseases and the underlying mechanisms. To model human neurodegenerative conditions, hippocampus-derived neurons were treated with glutamate. Using molecular and cellular biology approaches, we found that circFoxO3 expression was significantly higher in the glutamate treatment group than that in the control group. Furthermore, silencing of circFoxO3 protected HT22 cells from glutamate-induced oxidative injury through the inhibition of the mitochondrial apoptotic pathway. Collectively, our study demonstrates that endogenous circFoxO3 plays a key role in inducing apoptosis and neuronal cell death and may act as a novel therapeutic target for neurodegenerative diseases.

2.
J Cell Mol Med ; 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32150667

RESUMO

Acute myeloid leukaemia (AML) is the most common type of adult acute leukaemia and has a poor prognosis. Thus, optimal risk stratification is of greatest importance for reasonable choice of treatment and prognostic evaluation. For our study, a total of 1707 samples of AML patients from three public databases were divided into meta-training, meta-testing and validation sets. The meta-training set was used to build risk prediction model, and the other four data sets were employed for validation. By log-rank test and univariate COX regression analysis as well as LASSO-COX, AML patients were divided into high-risk and low-risk groups based on AML risk score (AMLRS) which was constituted by 10 survival-related genes. In meta-training, meta-testing and validation sets, the patient in the low-risk group all had a significantly longer OS (overall survival) than those in the high-risk group (P < .001), and the area under ROC curve (AUC) by time-dependent ROC was 0.5854-0.7905 for 1 year, 0.6652-0.8066 for 3 years and 0.6622-0.8034 for 5 years. Multivariate COX regression analysis indicated that AMLRS was an independent prognostic factor in four data sets. Nomogram combining the AMLRS and two clinical parameters performed well in predicting 1-year, 3-year and 5-year OS. Finally, we created a web-based prognostic model to predict the prognosis of AML patients (https://tcgi.shinyapps.io/amlrs_nomogram/).

3.
Environ Toxicol ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32167222

RESUMO

Glyburide is a classic antidiabetic drug that is dominant in inflammation regulation, but its specific role in ozone-induced lung inflammation and injury remains unclear. In order to investigate whether glyburide prevents ozone-induced pulmonary inflammation and its mechanism, C57BL/6 mice were intratracheally pre-instilled with glyburide or the vehicle 1 hour before ozone (1 ppm, 3 hours) or filtered air exposure. After 24 hours, the total inflammatory cells and total protein in bronchoalveolar lavage fluid (BALF) were detected. The pathological alternations in lung tissues were evaluated by HE staining. The expression of NLRP3, interleukin-1ß (IL-1ß), and IL-18 protein in lung tissues was detected by immunohistochemistry. Western blotting was used to examine the levels of caspase-1 p10 and active IL-1ß protein. Levels of IL-1ß and IL-18 in BALF were measured using ELISA kits. Glyburide treatment decreased the total cells in BALF, the inflammatory score, and the mean linear intercept induced by ozone in lung tissues. In addition, glyburide inhibited the expression of NLRP3, IL-18, and IL-1ß protein in lung tissues, and also suppressed NLRP3 inflammasome activation, including caspase-1 p10, active IL-1ß protein in lung tissues, IL-1ß, and IL-18 in BALF. These results demonstrate that glyburide effectively attenuates ozone-induced pulmonary inflammation and injury via blocking the NLRP3 inflammasome.

4.
J Clin Lab Anal ; : e23275, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32133697

RESUMO

BACKGROUND: Laboratory tests play an important role in the diagnosis of syphilis. This study aimed to compare and assess the performance of the Abbott chemiluminescent microparticle immunoassay (CMIA) and the ChIVD light-initiated chemiluminescent assay (LICA) in the detection of Treponema pallidum (TP) antibody. METHODS: A total of 10 498 serum samples were detected with two assays, and the Treponema pallidum particle agglutination assay (TPPA) and recombinant immunoblot assay (RIBA) methods were used for confirmation. The sensitivity, specificity, positive predictive value, and negative predictive value of the Abbott CMIA and ChIVD LICA were calculated. The coincidence rate between two assays was also evaluated. The causes of false positive and false negative of two assays were studied. RESULTS: For the Abbott CMIA and ChIVD LICA, the sensitivity was 94.44% and 98.15%, the specificity was 99.89% and 99.81%, the positive predictive value was 93.29% and 88.83%, and the negative predictive value was 99.91% and 99.97%, respectively. The coincidence rate between Abbott CMIA and ChIVD LICA was 99.26%, and κ value was .790. The disease of infertility, hypertensive disease, liver disease, and cancer were the common causes of false positive in both assays, while infertility was also the main reason lead to false negative. CONCLUSION: Our results demonstrated that the Abbott CMIA and ChIVD LICA generally had high sensitivity and specificity and therefore may be suitable for the detection of TP antibody and screening for syphilis.

5.
Sci Rep ; 10(1): 4626, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170163

RESUMO

miRNAs are endogenous regulatory factors that play pivotal roles in post-transcriptional regulation. However, their specific roles in early somatic embryogenesis (SE) remain unclear. Study of the SE system is fundamental for clarifying the molecular mechanisms in Dimocarpus longan. We identified 289 known miRNAs from 106 different miRNA families and 1087 novel miRNAs during early longan SE, including embryogenic callus (EC), incomplete pro-embryogenic culture (ICpEC), globular embryo (GE), and non-embryogenic callus (NEC). The abundances of known miRNAs were concentrated in GE. The differentially expression (DE) miRNAs showed five expression patterns during early SE. Largely miRNAs were expressed highly and specially in EC, ICpEC, and GE, respectively. Some miRNAs and putative target genes were enriched in lignin metabolism. Most potential targets were related to the pathways of plant hormone signal transduction, alternative splicing, tyrosine metabolism and sulfur metabolism in early longan SE. The regulatory relationships between dlo-miR166a-3p and DlHD-zip8, dlo-miR397a and DlLAC7, dlo-miR408-3p and DlLAC12 were confirmed by RNA ligase-mediated rapid amplification of cDNA ends. The expression patterns of eight DE miRNAs detected by qRT-PCR were consistent with RNA-seq. Finally, the miRNA regulatory network in early SE was constructed, which provided new insight into molecular mechanism of early SE in longan.

6.
Basic Res Cardiol ; 115(2): 22, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32112145

RESUMO

The roles and the underlying mechanisms of M1-type macrophages in angiogenesis and postmyocardial infarction (MI) cardiac repair have remained unclear. In this study, we investigated the role of M1-like macrophage-derived exosomes in a MI microenvironment. We found that the proinflammatory M1-like-type macrophages released an extensive array of proinflammatory exosomes (M1-Exos) after MI. M1-Exos exerted an anti-angiogenic effect and accelerated MI injury. They also exhibited highly expressed proinflammatory miRNAs, such as miR-155. miR-155 was transferred to endothelial cells (ECs), leading to the inhibition of angiogenesis and cardiac dysfunction by downregulating its novel target genes, including Rac family small GTPase 1 (RAC1), p21 (RAC1)-activated kinase 2 (PAK2), Sirtuin 1 (Sirt1), and protein kinase AMP-activated catalytic subunit alpha 2 (AMPKα2). M1-Exos depressed Sirt1/AMPKα2-endothelial nitric oxide synthase and RAC1-PAK2 signaling pathways by simultaneously targeting the five molecule nodes (genes), reduced the angiogenic ability of ECs, aggravated myocardial injury, and restrained cardiac healing. The elucidation of this mechanism provides novel insights into the functional significance of M1 macrophages and their derived exosomes on angiogenesis and cardiac repair. This mechanism can be used as a novel potential therapeutic approach for the prevention and treatment of MI.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32184191

RESUMO

Channel catfish (Ictalurus punctatus) is an important aquaculture species in China. In channel catfish, diseases such as haemorrhagic, sepsis and tail-rot disease are all caused by bacteria as general in China. Most of the pathogenic bacteria are Gram-negative bacteria. Liver transcriptome analysis of the co-injection of cortisol and lipopolysaccharide (LPS) was performed in this study. Preliminary evidence from the results suggest that after the emergence of immune stress, cortisol will up-regulate the complement cascade pathway, down-regulate the coagulation cascade pathway, down-regulate the platelet activation pathway, down-regulate antigen presentation pathway, and show complex regulation relationship to inflammatory factors. At 12 h, the number of differential genes regulated by cortisol was about half less than the number of differential genes regulated by LPS. At 24 h, there was no significant difference between the number of differential genes regulated by cortisol and LPS, but the types of differential genes vary widely. KEGG enrichment analysis found that cortisol regulated LPS-stimulated immune responses mainly focus on cytokines, complement and coagulation cascades pathways, antigen presentation pathways, haematopoiesis, and inflammation. It is suggested that there may be some strategic choice in the regulation of immune response by cortisol. These results will help understand the pathogenesis and host defence system in bacterial disease caused by Gram-negative bacteria.

8.
Chem Commun (Camb) ; 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32186550

RESUMO

For the first time, we report the design and fabrication of a ZnS nanoparticle-decorated silica fibre mesh (ZnS@SiO2) for localized H2S-amplified chemotherapy. With incorporation of DOX, implanted ZnS@SiO2 fibres enable sufficient on-site drug dosage and intracellular H2S content, inducing significant in vitro and in vivo tumour inhibition.

9.
J Ethnopharmacol ; : 112780, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32222575

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The Si-miao-yong-an decoction (SMYAD) is a famous traditional Chinese medicinal formula that has been used for centuries in ancient China for treating thromboangiitis obliterans. Because of its long history of use, it has been used to treat patients in China for thousands of years. In recent years, SMYAD has been widely used for treating cardiovascular and endocrine diseases. It was shown to significantly increase high-density lipoprotein-cholesterol levels and reduce total cholesterol and low-density lipoprotein-cholesterol levels in the serum. AIM OF THE STUDY: Herein, a serum metabonomics approach based on the HPLC-MS/MS method was adopted to evaluate the therapeutic effect of SMYAD on high-fat diet-induced hyperlipidemia, and investigate the mechanisms for treating hyperlipidemia. MATERIALS AND METHODS: Firstly, the change in body weight, liver histopathology, and serum biochemistry, including that in the levels of hepatotoxicity-related enzymes, oxidative stress indexes, and inflammatory factors were monitored in rats, to evaluate the therapeutic effect of SMYAD on high-fat diet-induced hyperlipidemia. Then, a serum metabolomics approach was applied, to cluster different groups using principle component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), as well as to screen out sensitive and reliable biomarkers. Finally, the metabolic pathways associated with specific biomarkers were analyzed, to understand the possible mechanism underlying the action of SMYAD. RESULTS: The results indicated that SMYAD had significant anti-hyperlipidemic, anti-oxidant, and anti-inflammatory effects. Based on the results of serum metabolomics analysis, the hyperlipidemic rats showed completely different results compared to the control rats; metabolite profiles of rats from the SMYAD treatment groups showed a trend comparable to those of the normal control group in a dose-dependent manner. Besides, twelve biomarkers associated with pyruvate metabolism, taurine and hypotaurine metabolism, TCA cycle, bile acid metabolism, and glucose metabolism were identified and confirmed, to clarify the mechanism of action of SMYAD. CONCLUSION: Using metabonomics technology, it was predicted that the therapeutic effects of SMYAD were associated with its anti-oxidation as well as anti-inflammatory activities and the adjustment of the pyruvate, taurine as well as hypotaurine metabolism pathways in the hyperlipidemic state. This study provided evidence regarding the clinical application of SMYAD and thoroughly explored the mechanism underlying the action of this traditional Chinese medicine.

10.
Cardiovasc Res ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049355

RESUMO

AIMS: Aging is a risk factor for cardiovascular diseases and adaptive immunity has been implicated in angiotensin (Ang) II-induced target-organ dysfunction. Herein, we sought to determine the role of T-cell senescence in Ang II-induced target organ impairment and to explore the underlying mechanisms. METHODS AND RESULTS: Flow cytometric analysis revealed that T cell derived from aged mice exhibited immuno-senescence. Adoptive transfer of aged T cells to immunodeficient RAG1 KO mice accelerates Ang II-induced cardiovascular and renal fibrosis compared with young T cell transfer. Aged T cells also promote inflammatory factor expression and superoxide production in these target organs. In vivo and in vitro studies revealed that Ang II promotes IFN-γ production in the aged T cells comparing to young T cells. Importantly, transfer of senescent T cell that IFN-γ KO mitigates the impairment. Aged T cell-conditioned medium stimulates inflammatory factor expression and oxidative stress in Ang II-treated renal epithelial cells compared with young T cells, and these effects of aged T cell-conditioned medium are blunted after IFN-γ-neutralizing antibody pretreatment. CONCLUSIONS: These results provide a significant insight into the contribution of senescent T cells to Ang II-induced cardiovascular dysfunction and provide an attractive possibility that targeting T cell specifically might be a potential strategy to treat elderly hypertensive patients with end-organ dysfunction. TRANSLATIONAL PERSPECTIVE: Aging is a risk factor for cardiovascular diseases. Adaptive immunity has been implicated in Ang II-induced target-organ dysfunction. Here, we utilized adoptive transfer of young or aged T cell into RAG1-/- mice and provide the direct evidence that senescent T-cell was more sensitive to Ang II stimulation and exerted an adverse impact on target-organ, in which senescent T cell-derived IFN-γ may play a critical role. These findings might shed new light on the contribution of T-cell senescence to target-organ injury in age-related hypertension.

11.
J Am Chem Soc ; 142(10): 4944-4954, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32069041

RESUMO

Pancreatic ductal adenocarcinoma, as one of the most aggressive cancers, is characterized by rich desmoplastic stroma that forms a physical barrier for anticancer drugs. To address this issue, we herein report a two-step sequential delivery strategy for targeted therapy of pancreatic cancer with gemcitabine (GEM). In this sequential strategy, metformin (MET) was first administrated to disrupt the dense stroma, based on the fact that MET downregulated the expression of fibrogenic cytokine TGF-ß to suppress the activity of pancreatic stellate cells (PSCs), through the 5'-adenosine monophosphate-activated protein kinase pathway of PANC-1 pancreatic cancer cells. In consequence, the PSC-mediated desmoplastic reactions generating α-smooth muscle actin and collagen were inhibited, which promoted the delivery of GEM and pH (low) insertion peptide (pHLIP) comodified magnetic nanoparticles (denoted as GEM-MNP-pHLIP). In addition, pHLIP largely increased the binding affinity of the nanodrug to PANC-1 cells. The targeted delivery and effective accumulation of MET/GEM-MNP-pHLIP in vivo were confirmed by magnetic resonance imaging enhanced by the underlying magnetic nanoparticles. The tumor growth inhibition of the sequential MET and GEM-MNP-pHLIP treatment were investigated on both subcutaneous and orthotopic tumor mice models. A remarkably improved therapeutic efficacy, for example, up to 91.2% growth inhibition ratio over 30 d of treatment, well-exemplified the novel cascade treatment for pancreatic cancer and the innovative use of MET.

12.
Ecotoxicol Environ Saf ; 193: 110257, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32088547

RESUMO

Chlorobenzenes (CBs) present in synthetic dyes are discharged into natural waters during the treatment of textile dyeing wastewater, which may have adverse effects on human and environment. In this study, the existence and removal of 12 CBs in different units of five treatment plants were examined. The ecological risk of CBs in textile dyeing wastewater was assessed by ambient severity (AS) and risk quotients (RQs). The results showed that trichlorobenzene, tetrachlorobenzene, pentachlorobenzene and hexachlorobenzene were ubiquitous in textile dyeing wastewater, and their distribution was similar. In one of the plants, the content of hexachlorobenzene was found to be as high as 9.277 µg/L in the raw water, which was an oil-water mixture. In other plants, there was no significant difference in the content and composition of CBs among influent and effluent suggesting that the conventional wastewater treatment plants cannot improve the existence of them. Monochlorobenzene and dichlorobenzene were not detected, which may have been related to strong volatility, biochemical properties, and weak instrument sensitivity. In the treatment process and effluent, trichlorobenzene is the main pollutant and accounted for 39.51% of all CB. CB removal was found only in the anaerobic system, while the aerobic system did not have the corresponding removal effect on CB and total organic carbon. According to ecological risk assessment, CBs in effluent has not been found the significant potential harm to human health (AS < 1), but posed moderate ecological risk to aquatic ecosystem (RQs > 0.1).

13.
Mol Genet Genomic Med ; : e1189, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32077254

RESUMO

BACKGROUND: Dysregulation of microRNAs (miRNAs) has been reported to be involved in the neuroinflammatory pathogenesis of PD. This study aimed to investigate the serum expression of microRNA-150 (miR-150) in Parkinson's disease (PD) patients and further uncover the regulatory effect of miR-150 on neuroinflammation. METHODS: Quantitative Real-Time PCR was used to measure the expression of miR-150. A receiver operating characteristic curve was applied to evaluate the diagnostic value of miR-150. The effect of miR-150 on neuroinflammation was analyzed by examining its correlation with proinflammatory cytokines and gain-of-function experiments in microglia treated with LPS. RESULTS: Serum miR-150 expression was downregulated in PD patients compared with the healthy controls, and served as a candidate diagnostic biomarker for the screening of PD cases. Negative correlation was found between miR-150 levels and the levels of procytokines in PD patients. By the treatment of LPS, microglia BV2 cells had a reduced expression of miR-150, and the enhanced neuroinflammatory responses were inhibited by the overexpression of miR-150. AKT3 was verified as a target of miR-150 in BV2 cells. CONCLUSION: All the data of this study revealed that the decreased serum miR-150 serves as a potential diagnostic biomarker. The methods to increase miR-150 expression may have a beneficial effect in PD via suppressing the neuroinflammation by targeting AKT3.

15.
Biomed Pharmacother ; 125: 109975, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32036223

RESUMO

Necrotizing enterocolitis (NEC) is one of the most common and devastating gastrointestinal diseases in preterm newborns, and its underlying mechanisms remain unclear. Non-coding RNAs (ncRNAs) play critical roles in intestinal diseases; however, little is known about their roles in the development of NEC. To gain a deeper understanding of the pathophysiological mechanism of NEC, long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and mRNAs were detected in an NEC rat model. In total, 1820 lncRNAs, 118 miRNAs and 929 mRNAs were differentially expressed in NEC group. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that these molecules were enriched in apoptosis, autophagic cell death, TLR4 signaling pathway, Notch signaling pathway, and mTOR signaling pathway. These pathways are thought to be closely associated with NEC. Furthermore, a lncRNA-miRNA interaction network was constructed, and four of the novel, differentially expressed lncRNAs with large changes were randomly verified using quantitative polymerase chain reaction (qPCR). The GO and KEGG pathway analysis of these four lncRNAs showed that they were associated with the negative regulation of TLR4 signaling pathway and Notch signaling pathway. In conclusion, our study revealed that these differentially expressed lncRNAs may participate in the development of NEC via interactions with miRNAs and may serve as possible biomarkers and target genes in NEC.

16.
Int J Biol Macromol ; 152: 1-10, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32045608

RESUMO

Channel catfish (Ictalurus punctatus) are one of the most important commercial freshwater fish in the world. China has been the major producer and consumer of channel catfish following the rapid development in the past three decades. In the present study, a novel orthologous myostatin gene, IpMSTNa, of channel catfish was identified based on homology cloning and genome locating. Multiple sequence alignments and gene structure analyses showed that the IpMSTNa gene and its deduced protein presented similar architectures to other known vertebrates. Phylogenetic and synteny analyses indicated that IpMSTNa belongs to MSTN1 orthologues. Pro-IpMSTNa protein is a typical disulphide-linked homodimer, with each chain containing an N-terminal pro-domain and a C-terminal unmatured GF domain, while pro-IpMSTNa present some significant differences in secondary structure and three-dimensional substances with pro-IpMSTNb. Relative expression level of the IpMSTNa gene upregulated rapidly and decreased dramatically during the embryonic and larval developmental stages, respectively. In addition, IpMSTNa displayed remarkably higher expression at most developmental stages compared to IpMSTNb. Tissue distribution analysis indicated that the IpMSTNa gene had a significantly higher level of expression than IpMSTNb in all selected tissues, with abundantly greater expression in the liver, muscle, gill and spleen, and moderately greater expression in the kidney, intestine, and head kidney. ISH analysis demonstrated that the expression signals of IpMSTNa and IpMSTNb at the selected developmental stages are consistent to qRT-PCR tests. Our study suggested that the IpMSTNa gene may have more biological functions, which have yet to be determined compared to the IpMSTNb gene.

17.
J Nat Prod ; 83(1): 8-13, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31904949

RESUMO

Nine previously undescribed prenylated p-terphenyls, prenylterphenyllins F-J (1, 2, 4-6) and prenylcandidusins D-G (3, 7-9), were isolated from an endophytic fungus, Aspergillus candidus LDJ-5. Their structures were determined from NMR and MS data. Differing from previously reported p-terphenyls, compound 3 represents a rare 6,5,6,6-fused ring system. Compounds 4-6 are antimicrobial, and compounds 1, 4, 6, and 9 are cytotoxic.

18.
Fish Physiol Biochem ; 46(1): 177-186, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31709461

RESUMO

The full-length cDNA coding IGF-I was cloned from the liver of Yellow catfish Pelteobagrus fulvidraco. The tissue distributions of IGF-I in adults were then analyzed by using real-time PCR. The effects of starvation (3 weeks) and subsequent refeeding (3 weeks) on the compensatory growth performance in juvenile fish weighing 3.80 ± 0.78 g and hepatic IGF-I mRNA expressions were also investigated. The cDNA obtained covered 884 bp with an open reading frame of 480 bp encoding 159 amino acids. It is composed of a signal peptide with 41 amino acids (AAs), a mature peptide comprising the B, C, A, and D domains (71 AAs) and E domain of 47 AAs. Sequence alignment and phylogenetic analysis revealed a high degree of conservation (71-87%) among the species of Siluriformes and some closely related species. In adults, the highest IGF-I expression was observed in the liver, followed by the brain, whereas relatively low expressions were detected in muscle and stomach. Both body weight and length increased significantly in fish fed to satiation continuously. Body weight, body length, condition factor, and hepatic IGF-I expressions were all decreased remarkably with increasing starvation times, but increased significantly after refeeding. The results showed that the expression of IGF-I was positively correlated with feed intakes and IGF-I may play a key regulatory role for somatic growth induced by compensatory growth in Yellow catfish.

19.
Plant Cell Physiol ; 61(2): 403-415, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31693150

RESUMO

Although control of xylem ion loading is essential to confer salinity stress tolerance, specific details behind this process remain elusive. In this work, we compared the kinetics of xylem Na+ and K+ loading between two halophytes (Atriplex lentiformis and quinoa) and two glycophyte (pea and beans) species, to understand the mechanistic basis of the above process. Halophyte plants had high initial amounts of Na+ in the leaf, even when grown in the absence of the salt stress. This was matched by 7-fold higher xylem sap Na+ concentration compared with glycophyte plants. Upon salinity exposure, the xylem sap Na+ concentration increased rapidly but transiently in halophytes, while in glycophytes this increase was much delayed. Electrophysiological experiments using the microelectrode ion flux measuring technique showed that glycophyte plants tend to re-absorb Na+ back into the stele, thus reducing xylem Na+ load at the early stages of salinity exposure. The halophyte plants, however, were capable to release Na+ even in the presence of high Na+ concentrations in the xylem. The presence of hydrogen peroxide (H2O2) [mimicking NaCl stress-induced reactive oxygen species (ROS) accumulation in the root] caused a massive Na+ and Ca2+ uptake into the root stele, while triggering a substantial K+ efflux from the cytosol into apoplast in glycophyte but not halophytes species. The peak in H2O2 production was achieved faster in halophytes (30 min vs 4 h) and was attributed to the increased transcript levels of RbohE. Pharmacological data suggested that non-selective cation channels are unlikely to play a major role in ROS-mediated xylem Na+ loading.

20.
Int J Neurosci ; 130(2): 186-192, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31696761

RESUMO

Background and Purpose: Oxidative stress is involved in the development of infections. However, whether oxidative stress indicators can be used as markers of stroke-associated infection (SAI) is still unclear. The purpose of this study was to test the predictive values of superoxide dismutase (SOD) and malondialdehyde (MDA) levels for SAI incidence.Methods: A total of 45 consecutive patients with ischemic stroke who were admitted to our hospital were enrolled. A prospective study was carried out to observe the occurrence of SAI during the first 7 days after stroke. Accordingly, the patients were divided into SAI and non-SAI groups. The relationship between SOD and MDA serum levels and SAI was analyzed.Results: The patients in the SAI group had significantly higher serum SOD levels than those in the non-SAI group (41.638 ± 3.428 U/ml vs. 36.542 ± 9.114 U/ml, p = 0.033). However, there were no significant differences in MDA levels between the SAI and non-SAI group (p > 0.05). The discriminating ability of serum SOD level for SAI was measured using an ROC curve. Serum level of SOD >38.16 U/ml was useful in diagnosing SAI with a sensitivity of 88% and a specificity of 61%. Kaplan-Meier curves showed that the group with serum SOD level >38.16 U/ml had higher rates of SAI incidence (χ2 = 9.688, p = 0.002; log rank test). Furthermore, Cox regression analysis indicated that a serum SOD level >38.16 U/ml was an independent risk factor for SAI (hazard ratio = 5.836; 95% CI, 1.298-26.244; p = 0.021).Conclusions: Acute-phase serum SOD level could be a predictor of SAI.

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