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1.
Curr Genet ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31489464

RESUMO

Ustilaginoidea virens is an important fungus causing rice false smut, a devastating disease on spikelets of rice. In this study, we identified and characterized two CMGC (CDK/MAPK/GSK3/CLK) kinase genes, UvPmk1 and UvCDC2, in U. virens. Although UvPmk1 and UvCDC2 are, respectively, homologous to Fus3/Kss1 mitogen-activated protein kinases (MAPKs) and cyclin-dependent kinases (CDKs), they all have a conserved serine/threonine protein kinase domain. The qRT-PCR analysis of the relative expression of UvPmk1 and UvCDC2 during the infection of U. virens showed that these two genes were highly expressed during infection. UvPmk1 and UvCDC2 knockout mutants exhibited no significant changes in mycelial vegetative growth but decreases in conidiation. In addition, both UvPmk1 and UvCDC2 knockout mutants showed increases in tolerance to hyperosmotic and cell wall stresses, but they, respectively, exhibited decreases and increases in tolerance to oxidative stress compared with the wild-type strain HWD-2. Pathogenicity and infection assays demonstrated the defective growth of infection hyphae and significant loss of virulence in UvPmk1 and UvCDC2 knockout mutants. Taken together, our results demonstrate that UvPmk1 and UvCDC2 play important roles in the conidiation, stress response, and pathogenicity of U. virens.

2.
Environ Sci Technol ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31507168

RESUMO

The excellent permeability and selectivity of reduced graphene oxide (rGO) membranes have been demonstrated both theoretically and experimentally; however, strategies for the fabrication of highly stable, anti-fouling rGO membranes with a facile recovery after fouling have rarely been investigated. In this work, we report a structurally durable rGO-based hollow fiber membrane that allows high-pressure (at least 1 bar) back-flushing. This is achieved by sandwiching the rGO layer between a carbon nanotube (CNT) protective layer and a polyacrylonitrile (PAN) support. The CNT layer could also function as a pre-filtration and pre-adsorption microsystem and endow a higher resistance against fouling. This is experimentally confirmed by the much higher normalized permeance (0.82-0.92) of the CNT/rGO/PAN membranes than the simple rGO/PAN membranes (0.42-0.53) under the same operating conditions. Additionally, under a low cathode potential (0.9 V), the membrane could easily be renewed after fouling by simple back-flushing with a flux recovery ratio of ~96%. An investigation of the mechanism indicates that electrostatic repulsive forces promote the desorption of charged organic foulants (e.g., humic acid and dyes) from the rGO and CNT layers, and they can subsequently be removed from the membrane with water.

3.
Cell Death Dis ; 10(9): 678, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515489

RESUMO

Neutrophil extracellular traps (NETs) may play a critical role in smoking-related chronic airway inflammation. However, the mechanism by which NETs induced by cigarette smoke initiate the adaptive immunity in chronic obstructive pulmonary disease (COPD) is not fully understood. In this study, we explored the effects of NETs induced by cigarette smoke on the myeloid dendritic cells (mDCs) and Th1 and Th17 cells. Additionally, we observed the inhibitory effect of erythromycin on NETs induced by cigarette smoke. We found that elevated NET levels in the sputum of COPD patients were correlated with the circulating Th1 response, mDC activation and airflow limitation. NETs induced by cigarette smoke extract (CSE) could activate monocyte-derived mDCs and promote Th1 and Th17 differentiation in vitro. Erythromycin effectively inhibited NET formation induced by CSE. In vivo, erythromycin decreased NETs in the airway and ameliorated emphysema with Th1 and Th17 cell down-regulation and CD40+ and CD86+ mDCs suppression in mice chronically exposed to cigarette smoke. These findings provide direct evidence that NETs promote the differentiation of Th1 and Th17 and play a role in the adaptive immunity of smoking-related chronic lung inflammation. Erythromycin is a potential therapeutic strategy for NETs inhibition in COPD.

4.
Phytomedicine ; 64: 153084, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31514083

RESUMO

BACKGROUND: Metastasized melanoma is extremely difficult to treat. Activation of C-C chemokine receptor type 7 (CCR7) has been linked to melanoma metastasis. CCR7 can be directly regulated by miR-let-7. We have previously shown that an ethanolic extract of an herbal formula comprising Sophorae Flos and Lonicerae Japonicae Flos (SLE) inhibits melanoma cell migration and invasion. PURPOSE: In this study, we determined whether SLE suppresses melanoma metastasis, and whether regulation of miR-let-7a/f-CCR7 signaling is involved in the effect. STUDY DESIGN AND METHODS: Small RNA sequencing was conducted to compare miRNA expression profiles of B16F10 tumors dissected from SLE-treated or untreated mice. Western blot and RT-qPCR analyses were employed to examine protein and miRNA levels, respectively. A B16F10 melanoma lung metastasis mouse model was used to evaluate the effects of SLE on melanoma metastasis. MiR-let-7a/f-knockdown and CCR7-overexpression cell models were used to investigate the involvement of miR-let-7a/f-CCR7 signaling in the anti-metastatic effects of SLE. RESULTS: It was found that SLE upregulated levels of miR-let-7a/f in B16F10 melanoma tissues. SLE significantly elevated levels of miR-let-7a/f, lowered the protein level of CCR7, inhibited the phosphorylation of CCR7 downstream molecules p38 and JNK in B16F10 and A375 melanoma cells. SLE inhibited B16F10 melanoma lung metastasis in mice. SLE upregulated levels of miR-let-7a/f, and lowered protein levels of CCR7, MMP-2, MMP-9, phospho-p38 (Thr180/Tyr182) and phospho-JNK (Thr183/Tyr185) in melanoma-invaded lung tissues. Knockdown of miR-let-7a/f diminished the effects of SLE on CCR7 signaling in, and invasion of, melanoma cells. Overexpression of CCR7 lessened the effects of SLE in inhibiting the phosphorylation of p38 and JNK in, and the invasive capability of, melanoma cells. CONCLUSION: We for the first time demonstrated that SLE inhibits melanoma metastasis in mice, and that regulation of the miR-let-7a/f-CCR7 pathway contributes to the anti-metastatic mechanisms of SLE. These findings provide a pharmacological basis for developing SLE as a modern agent for treating metastatic melanoma. Additionally and importantly, this study suggests that regulating the miR-let-7a/f-CCR7 pathway is a novel strategy for controlling melanoma metastasis.

5.
Mol Ther Nucleic Acids ; 17: 840-851, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31465963

RESUMO

Although accumulating evidence has demonstrated the key roles of enhancers in gene expression regulation, the contribution of genome-wide enhancer-enhancer interactions to developmental decisions remains unclear. Here we explored the cooperative regulation patterns among enhancers to understand their regulatory mechanism. We first filtered robust enhancers in embryonic stem cells (ESCs) through integrating bidirectional transcription, genomic location, and epigenetic modification. Genome-wide enhancer-enhancer interactions were then identified based on enhancer-promoter relationships that were derived from Hi-C data. We further explored the interacting principles of the identified enhancer-enhancer interactions. The results revealed that the observed cooperativity occurred mainly between enhancers distributed within a 1-kb to 10-Mb distance across the genome. In addition, enhancer-enhancer pairs had higher expression correlations than non-interacting pairs. Finally, we identified robust enhancers during human cardiac commitment, and we found that enhancers exhibited strong stage-specific expression patterns. We further inferred the enhancer-enhancer interactions based on RNA sequencing (RNA-seq) data in heart development, according to the regulatory principles characterized from Hi-C data. The identified enhancer-enhancer interaction networks (EEINs) presented highly dynamic linkages. Moreover, enhancers cooperatively targeted many marker genes in each developmental stage to regulate stage-specific functions, which contribute to the organization of cell identity in heart development. Our work will increase the understanding of enhancer regulation in human heart development.

6.
Kaohsiung J Med Sci ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31433556

RESUMO

In this study, a novel mixed polymeric micelles formed from biocompatible polymers, poly(ethylene glycol)-poly(lactide) (mPEG-PLA) and poly(ethylene glycol)-poly(ɛ-caprolactone) (mPEG-PCL), used as a novel nanocarrier to encapsulate gambogenic acid (GNA). GNA-loaded mixed polymeric micelles (GNA-MMs) was prepared by cosolvent evaporation method. The mean average size of GNA-MMs was (83.23 ± 1.06) nm (n = 3) and entrapment efficiency (EE%) of GNA-MMs was (90.18 ± 2.59) % (n = 3) as well as (12.36 ± 0.64) % (n = 3) for drug loading (DL%). Transmission electron microscopy revealed that the GNA-MMs were spherical with "core-shell" structures. Compared with free GNA solution, in vitro release of GNA from GNA-MMs showed a two-phase sustained release profile: an initial relatively fast phase and followed by a slower release phase. Pharmacokinetic results also indicated that the GNA-MMs have longer systemic circulation time and slower plasma elimination rate than free GNA solution. Moreover, the in vitro cytotoxicity assay showed that the IC50 values on HepG2 cells for GNA-MMs and free GNA were (5.67 ± 0.02) µM and (9.02 ± 0.03) µM, respectively. In addition, GNA-MMs significantly increased the HepG2 cellular apoptosis in a concentration-dependent manner. In conclusion, the results showed that mPEG-PLA/mPEG-PCL mixed micelles may serve as an ideal drug delivery system for GNA to prolong drug circulation time in body, enhance bioavailability and retained its potent antitumor effect.

7.
Virulence ; 10(1): 754-767, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31429624

RESUMO

Clostridium perfringens is a common opportunistic pathogen endangering livestock and poultry breeds. Here, using enhanced green fluorescent protein as screening marker, a recombinant lactobacillus tetravalent vaccine constitutively expressing α, ε, ß1, and ß2 toxoids of C. perfringens was developed, and its immunogenicity in mice was investigated via oral administration. This probiotic vaccine could effectively induce antigen-specific secretory IgA (sIgA)-based mucosal and IgG-based humoral immune responses, and significantly high levels (p< 0.05) of cytokines IL-2, IL-4, IL-10, IL-12, IL-17, and IFN-γ were produced in immunized mice. Moreover, lymphoproliferation and percentage of CD4+ and CD8+ T cells significantly increased in mice of the probiotic vaccine group. Challenge experiments were performed in mice with C. perfringens toxinotypes A, C, and D crude toxins to evaluate protection efficiency of the probiotic vaccine, using a commercial inactivated C. perfringens vaccine made by C. perfringens toxinotypes A, C, and D as vaccine control. We observed 80% protection rate in the probiotic vaccine group, which was higher than commercial vaccine group, whereas all mice in control groups died and obvious histopathological changes were observed in liver, spleen, kidney, and intestines of mice. Significantly, we compared the immunogenicity and protection efficiency of lactobacillus constitutive expression system and lactobacillus inducible expression system, and results showed that lactobacillus constitutive expression system has obvious advantages. Our study clearly demonstrated that the probiotics vaccine could effectively induce mucosal, humoral, and cellular immunity, and provide effective protection against C. perfringens toxins, suggesting a promising strategy for the development of oral vaccine against C. perfringens.

8.
J Med Genet ; 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31413119

RESUMO

BACKGROUND: Neuronal intranuclear inclusion disease (NIID) is a heterogenous neurodegenerative disorder named after its pathological features. It has long been considered a disease of genetic origin. Recently, the GGC repeated expansion in the 5'-untranslated region (5'UTR) of the NOTCH2NLC gene has been found in adult-onset NIID in Japanese individuals. This study was aimed to investigate the causative mutations of NIID in Chinese patients. METHODS: Fifteen patients with NIID were identified from five academic neurological centres. Biopsied skin samples were analysed by histological staining, immunostaining and electron microscopic observation. Whole-genome sequencing (WGS) and long-read sequencing (LRS) were initially performed in three patients with NIID. Repeat-primed PCR was conducted to confirm the genetic variations in the three patients and the other 12 cases. RESULTS: Our patients included 14 adult-onset patients and 1 juvenile-onset patient characterised by degeneration of multiple nervous systems. All patients were identified with intranuclear inclusions in the nuclei of fibroblasts, fat cells and ductal epithelial cells of sweat glands. The WGS failed to find any likely pathogenic variations for NIID. The LRS successfully identified that three patients with adult-onset NIID showed abnormalities of GGC expansion in 5'UTR of the NOTCH2NLC gene. The GGC repeated expansion was further confirmed by repeat-primed PCR in seven familial cases and eight sporadic cases. CONCLUSION: Our findings provided evidence that confirmed the GGC repeated expansion in the 5'UTR of the NOTCH2NLC gene is associated with the pathogenesis of NIID. Additionally, the GGC expansion was not only responsible for adult-onset patients, but also responsible for juvenile-onset patients.

9.
Aging (Albany NY) ; 11(16): 6120-6133, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467256

RESUMO

MicroRNAs (miRNAs) have emerged as critical regulators in the pathology of Alzheimer's disease (AD). MiR-181a is associated with hippocampal memory formation and aberrantly expressed in patients with mild cognitive impairment (MCI), however, little is known about its role and underlying mechanism involved in AD. Here, we report that miR-181a expression declines in APP/PS1 mice, synchronous with the increase in amyloid ß (Aß) level, which suggests a reverse correlation between miR-181a level and AD development. Additionally, lentiviral overexpression of miR-181a via intrahippocampal injection ameliorates cognitive deficits and amyloid plaque deposition in APP/PS1 mice, indicating a beneficial role of miR-181a against AD progression. Moreover, miR-181a decelerates pericyte loss and blood-brain barrier breakdown in APP/PS1 mice. Furthermore, miR-181a protects against Aß accumulation-induced pericyte apoptosis in vitro, which is attributed to the negative regulation of FOXO1 by miR-181a, since FOXO1 restoration abolishes miR-181a protective role against pericyte apoptosis. Altogether, these results may identify miR-181a as a novel regulator of AD pathology, and also implicate that the protection of miR-181a in blood-brain barrier pericytes may underlie its ameliorating effect on APP/PS1 mice.

10.
J Agric Food Chem ; 67(31): 8573-8580, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31293156

RESUMO

Glycosylation endows both natural and synthetic small molecules with modulated physicochemical and biological properties. Plant and bacterial glycosyltransferases capable of decorating various privileged scaffolds have been extensively studied, but those from kingdom Fungi still remain underexploited. Here, we use a combination of genome mining and heterologous expression techniques to identify four novel glycosyltransferase-methyltransferase (GT-MT) functional modules from Hypocreales fungi. These GT-MT modules display decent substrate promiscuity and regiospecificity, methylglucosylating a panel of natural products such as flavonoids, stilbenoids, anthraquinones, and benzenediol lactones. Native GT-MT modules can be split up and regrouped into hybrid modules with similar or even improved efficacy as compared with native pairs. Methylglucosylation of kaempferol considerably improves its insecticidal activity against the larvae of oriental armyworm Mythimna separata (Walker). Our work provides a set of efficient biocatalysts for the combinatorial biosynthesis of small molecule glycosides that may have significant importance to the pharmaceutical, agricultural, and food industries.


Assuntos
Proteínas Fúngicas/química , Glicosiltransferases/química , Hypocreales/enzimologia , Metiltransferases/química , Fenóis/química , Animais , Biocatálise , Cristalografia por Raios X , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glicosilação , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Hypocreales/genética , Inseticidas/química , Inseticidas/farmacologia , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Mariposas/efeitos dos fármacos , Fenóis/farmacologia , Especificidade por Substrato
11.
Mol Ther Nucleic Acids ; 17: 362-373, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31302496

RESUMO

The accumulation of somatic driver mutations in the human genome enables cells to gradually acquire a growth advantage and contributes to tumor development. Great efforts on protein-coding cancer drivers have yielded fruitful discoveries and clinical applications. However, investigations on cancer drivers in non-coding regions, especially long non-coding RNAs (lncRNAs), are extremely scarce due to the limitation of functional understanding. Thus, to identify driver lncRNAs integrating multi-omics data in human cancers, we proposed a computational framework, DriverLncNet, which dissected the functional impact of somatic copy number alteration (CNA) of lncRNAs on regulatory networks and captured key functional effectors in dys-regulatory networks. Applying it to 5 cancer types from The Cancer Genome Atlas (TCGA), we portrayed the landscape of 117 driver lncRNAs and revealed their associated cancer hallmarks through their functional effectors. Moreover, lncRNA RP11-571M6.8 was detected to be highly associated with immunotherapeutic targets (PD-1, PD-L1, and CTLA-4) and regulatory T cell infiltration level and their markers (IL2RA and FCGR2B) in glioblastoma multiforme, highlighting its immunosuppressive function. Meanwhile, a high expression of RP11-1020A11.1 in bladder carcinoma was predictive of poor survival independent of clinical characteristics, and CTD-2256P15.2 in lung adenocarcinoma responded to the sensitivity of methyl ethyl ketone (MEK) inhibitors. In summary, this study provided a framework to decipher the mechanisms of tumorigenesis from driver lncRNA level, established a new landscape of driver lncRNAs in human cancers, and offered potential clinical implications for precision oncology.

12.
Mater Sci Eng C Mater Biol Appl ; 103: 109765, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349411

RESUMO

Fully degradable poly lactic acid based composite reinforced with 20 vol% magnesium alloy wires (MAWs) is prepared for weight bearing bone fracture healing. The degradation behaviors of the composite in the consistent and staged dynamic environments are investigated. The results suggest that dynamic loading would overall accelerate the degradation of the composite. As the loading magnitude increases from 0.2 MPa to 1 MPa or frequency from 0.5 Hz to 2.5 Hz, the degradation rate goes up. Under the staged dynamic loading condition, the degradation behaviors of the composite would show staged change determined by the dynamic loading condition at each stage. A numerical model is proposed to systematically depict the mechanical performances of the composite in the consistent and staged dynamic environments. The composite could theoretically provide sufficient stabilization for >8 weeks in a feasible dynamic environment to achieve successful bone fracture healing.

13.
BMC Med Genet ; 20(1): 129, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31340771

RESUMO

BACKGROUND: Several studies have been performed to investigate the associations between interleukin (IL)-8 rs4073 polymorphism and acute pancreatitis (AP), but the results are inconclusive. We conducted this cumulative meta-analysis for a precise estimate of the relationship between IL-8 rs4073 polymorphism and acute pancreatitis. METHODS: We searched the electronic databases for relevant studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the strength of the associations. For a better presentation of how the pooled ORs changed as updated evidence accumulated, we used forest plots from a cumulative meta-analysis method. RESULTS: Ten studies involving 1646 AP patients and 1816 controls were finally included in this meta-analysis. Cumulative meta-analyses indicated there is a consistent trend toward association after the initial discovery. Under the allelic, dominant, recessive and homozygous models, the pooled ORs were 1.265 (1.147-1.395, p < 0.001), 1.304 (1.127-1.508, p < 0.001), 1.431 (1.203-1.702, p < 0.001), and 1.634 (1.334-2.001, p < 0.001), respectively. CONCLUSIONS: This meta-analysis demonstrated a suggestive result that people who carried the risk A allele of the IL-8 rs4073 polymorphism may be more sensitive to acute pancreatitis.

14.
Anal Chim Acta ; 1075: 71-80, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31196425

RESUMO

In this work, porphyrin-based 2D MOF CuTCPP/platelet ordered mesoporous carbon (pOMC) composites were successfully synthesized by conventional solvothermal reaction. The introduction of pOMC increases conductivity of CuTCPP/pOMC composites, weakens accumulation of the CuTCPP layers, and exposes active sites of CuTCPP. CuTCPP/pOMC composites show high electro-catalytic activity to the oxidation of hydroxylamine and the redox of chlorogenic acid. An electrochemical sensor based on CuTCPP/pOMC was constructed for quantitative determination of hydroxylamine and chlorogenic acid, and relevant mechanisms were discussed. Under optimized conditions, the fabricated sensor displays two wide linear responses in the ranges of 5.8-733.8 µM and 733.8-2933.8 µM for hydroxylamine, with a rapid response time about 1 s. For chlorogenic acid, the sensor presents linear responses in the ranges of 0.1-2 µM and 2-15 µM, with a high sensitivity of 10.18 µA/µM. The sensor was used to detect hydroxylamine and chlorogenic acid in real samples, and satisfactory results were obtained. The synthesis of CuTCPP/pOMC composites provides new strategy for designing electrochemical sensors based on 2D MOFs.

15.
Pathobiology ; : 1-11, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31242482

RESUMO

BACKGROUND: Macrolides have anti-inflammatory and antioxidative stress function, but their pharmacological regulation remains unclear. Sirtuin 1 (SIRT1) is redox-sensitive protein belongs to class III histone/protein deacetylases, SIRT1 regulates the acetylation/expression of nuclear factor κB (NF-κB) and is involved in the airway inflammation of chronic obstructive pulmonary disease. OBJECTIVES: The present study was designed to examine the effects of erythromycin (EM) on the SIRT1-NF-κB axis and NF-κB-dependent proinflammatory cytokines. METHODS: Human macrophages were preincubated with EM and then treated with cigarette smoke extract (CSE). The mice were treated by injecting drugs to gastric with EM before cigarette smoke exposure. Reactive oxygen species (ROS) released by treated human macrophages were detected using flow cytometry. The expression of SIRT1 and NF-κB was analyzed by western blotting. SIRT1 and the RelA/p65 subunits of NF-κB interaction were detected by coimmunoprecipitation. We found that EM suppressed CSE-induced ROS released in human macrophages, which coincided with increases in SIRT1 protein expression in the macrophages and lungs of mice, resulting in suppressed -NF-κB acetylation and expression correlated with a reduction of inflammatory mediators. CONCLUSION: These findings suggest that EM increased SIRT1, leading to acetylation/expression of NF-κB, and thereby decreasing cigarette smoke-driven NF-κB-dependent proinflammatory cytokine.

16.
Appl Microbiol Biotechnol ; 103(16): 6645-6655, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31240365

RESUMO

High-yielding industrial Streptomyces producer is usually obtained by multiple rounds of random mutagenesis and screening. These strains have great potential to be developed as the versatile chassis for the discovery and titer improvement of desired heterologous products. Here, the industrial strain Streptomyces rimosus 461, which is a high producer of oxytetracycline, has been engineered as a robust host for heterologous expression of chlortetracycline (CTC) biosynthetic gene cluster. First, the industrial chassis strain SR0 was constructed by deleting the whole oxytetracycline gene cluster of S. rimosus 461. Then, the biosynthetic gene cluster ctc of Streptomyces aureofaciens ATCC 10762 was integrated into the chromosome of SR0. With an additional constitutively expressed cluster-situated activator gene ctcB, the CTC titer of the engineering strain SRC1 immediately reached 1.51 g/L in shaking flask. Then, the CTC titers were upgraded to 2.15 and 3.27 g/L, respectively, in the engineering strains SRC2 and SRC3 with the enhanced ctcB expression. Further, two cluster-situated resistance genes were co-overexpressed with ctcB. The resultant strain produced CTC up to 3.80 g/L in shaking flask fermentation, which represents 38 times increase in comparison with that of the original producer. Overall, SR0 presented in this study have great potential to be used for heterologous production of tetracyclines and other type II polyketides.

17.
Int J Mol Sci ; 20(11)2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31195741

RESUMO

Winter rapeseed is not only an important oilseed crop, but also a winter cover crop in Northern China, where its production was severely limited by freezing stress. As an overwinter crop, the production is severely limited by freezing stress. Therefore, understanding the physiological and molecular mechanism of winter rapeseed (Brassica napus L.) in freezing stress responses becomes essential for the improvement and development of freezing-tolerant varieties of Brassica napus. In this study, morphological, physiological, ultrastructure and transcriptome changes in the Brassica napus line "2016TS(G)10" (freezing-tolerance line) that was exposed to -2 °C for 0 h, 1 h, 3 h and 24 h were characterized. The results showed that freezing stress caused seedling dehydration, and chloroplast dilation and degradation. The content of malondialdehyde (MDA), proline, soluble protein and soluble sugars were increased, as well as the relative electrolyte leakage (REL) which was significantly increased at frozen 24 h. Subsequently, RNA-seq analysis revealed a total of 98,672 UniGenes that were annotated in Brassica napus and 3905 UniGenes were identified as differentially expressed genes after being exposed to freezing stress. Among these genes, 2312 (59.21%) were up-regulated and 1593 (40.79%) were down-regulated. Most of these DEGs were significantly annotated in the carbohydrates and energy metabolism, signal transduction, amino acid metabolism and translation. Most of the up-regulated DEGs were especially enriched in plant hormone signal transduction, starch and sucrose metabolism pathways. Transcription factor enrichment analysis showed that the AP2/ERF, WRKY and MYB families were also significantly changed. Furthermore, 20 DEGs were selected to validate the transcriptome profiles via quantitative real-time PCR (qRT-PCR). In conclusion, the results provide an overall view of the dynamic changes in physiology and insights into the molecular regulation mechanisms of winter Brassica napus in response to freezing treatment, expanding our understanding on the complex molecular mechanism in plant response to freezing stress.

18.
J Cell Physiol ; 234(12): 23518-23527, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31219186

RESUMO

Melanoma is responsible for the majority of deaths caused by skin cancer. Antitumor activity of microRNA-329 (miR-329) has been seen in several human cancers. In this study, we identify whether miR-329 serves as a candidate regulator in melanoma. Melanoma-related differentially expressed genes were screened with its potential molecular mechanism predicted. Melanoma tissues and pigmented nevus tissues were collected, where the levels of miR-329 and high-mobility group box 2 (HMGB2) were determined. To characterize the regulatory role of miR-329 on HMGB2 and the ß-catenin pathway in melanoma cell activities, miR-329 mimics, miR-329 inhibitors, and siRNA-HMGB2 were transfected into melanoma cells. Cell viability, migration, invasion, cell cycle, and apoptosis were assessed. miR-329 was predicted to influence melanoma by targeting HMGB2 via the ß-catenin pathway. High level of HMGB2 and low miR-329 expression were observed in melanoma tissues. HMGB2 was targeted and negatively regulated by miR-329. In melanoma cells transfected with miR-329 mimics or siRNA-HMGB2, cell proliferation, migration, and invasion were impeded, yet cell cycle arrest and apoptosis were promoted, corresponding to decreased levels of ß-catenin, cyclin D1, and vimentin and increased levels of GSK3ß and E-cadherin. Collectively, our results show that miR-329 can suppress the melanoma progression by downregulating HMGB2 via the ß-catenin pathway.

19.
J Cardiothorac Vasc Anesth ; 33(8): 2231-2236, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31060941

RESUMO

OBJECTIVE: To identify the predictors of in-hospital mortality in patients who develop perioperative acute ischemic stroke (PAIS) associated with noncardiac, nonvascular, and non-neurologic surgery. DESIGN: Retrospective study. SETTING: University-affiliated hospital. PARTICIPANTS: The study comprised 100 patients with PAIS. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The data of 351,531 patients who underwent noncardiac, nonvascular, and non-neurologic surgery in the authors' hospital between January 2003 and December 2016 were retrospectively reviewed. PAIS occurred in 100 patients. The incidence of PAIS (overall 2.8/10,000) was significantly lower in patients <45 years old (0.12/10,000) than in patients >75 years old (15.79/10,000; p < 0.001). The in-hospital mortality rate was higher among patients with PAIS (26%) than among patients without PAIS (0.34%; p < 0.01). Multiple logistic regression analysis revealed the following independent risk factors for in-hospital mortality: preoperative atrial fibrillation (odds ratio [OR] 9.013, 95% confidence interval [CI] 1.400-58.016; p = 0.021), disturbance of consciousness as the first PAIS symptom (OR 5.561, 95% CI 1.521-20.332; p = 0.009), no anticoagulant/antiplatelet therapy after PAIS (OR 8.196, 95% CI 1.017-66.065; p= 0.048), diuretic treatment (OR 4.942, 95% CI 1.233-19.818; p = 0.024), and pulmonary infection (OR 6.979, 95% CI 1.853-26.291; p = 0.004). CONCLUSIONS: The risk of PAIS after noncardiac, nonvascular, and non-neurologic surgery significantly increased with age, and development of PAIS increased the mortality rate. Among these patients, the independent predictors of in-hospital mortality were preoperative atrial fibrillation, disturbance of consciousness as the first PAIS symptom, no anticoagulant/antiplatelet therapy after PAIS, diuretic treatment, and pulmonary infection.

20.
Talanta ; 200: 300-306, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036188

RESUMO

In this work, the low-cost nitrogen-doped graphene-like mesoporous nanosheets (N-GMNs) was synthesized from the biomass waste of okara for the first time for the construction of a nonenzymatic amperometric vitamin C biosensor. The N-GMNs modified glassy carbon electrode (N-GMNs/GCE) shows much lower overpotential for the electrooxidation of vitamin C comparing to the traditional GCE as well as the GCE modified by carbon nanotubes (CNTs/GCE), indicating the promising of N-GMNs/GCE for the sensitive and selective nonenzymatic amperometric vitamin C biosensing. As a nonenzymatic amperometric biosensor for vitamin C, the N-GMNs/GCE shows a higher sensitivity (144.65 µA mM-1 cm-2), a wider linear range (10-5640 µmol L-1) and a lower detection limit (0.51 µmol L-1) than GCE, CNTs/GCE or some of recently reported nanomaterials-based electrochemical vitamin C biosensors. Especially, the vitamin C concentration in real samples of commercial beverage, vitamin C injection and commercial juice can be determined by the proposed N-GMNs/GCE with satisfied results. Therefore, the utilization of okara as the raw material for the synthesis of nanostructured carbon of N-GMNs is a green method to fabricate an advanced and low-cost electrode material for developing the nonenzymatic electrochemical biosensor for vitamin C detection.


Assuntos
Ácido Ascórbico/análise , Grafite/química , Nanoestruturas/química , Nitrogênio/química , Resíduos/análise , Biomassa , Técnicas Biossensoriais/economia , Técnicas Eletroquímicas/economia , Eletrodos , Grafite/economia , Nanoestruturas/economia , Nitrogênio/economia , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Água/química
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