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1.
Pest Manag Sci ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489764

RESUMO

BACKGROUND: Interactions between herbivorous insects and entomoviruses may depend on host plant, perhaps mediated through changes in herbivore innate immunity. RESULTS: Caterpillars (Spodoptera exigua) fed Glycine max had high viral loads and low melanization rates together with low melanization enzyme [PO, DDC, TH] activities and gene expressions. Caterpillars fed Ipomoea aquatica had low viral loads and high melanization, gene activities and gene expressions while those fed Brassica oleracea or artificial diet had intermediate levels of each. Melanization rates were negatively correlated with viral loads and positively correlated with activity and expression of each of the three enzymes. Some diet effects on enzymes were constitutive because the same diets led to low (G. max) or high (I. aquatica) melanization related gene activities and expressions without infection. CONCLUSION: Diet influences the interactions between insect herbivores and viruses by shaping the innate immune response both at the onset of infection and afterwards as viral loads accumulate over a period of days. In addition, diets that lead to low viral loads are associated with high activities and gene expressions of a variety of melanization related enzymes suggesting a common causative mechanism. © 2019 Society of Chemical Industry.

2.
Plant Dis ; 103(11): 2759-2763, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31509496

RESUMO

Rice blast caused by the fungus Magnaporthe oryzae is one of the most destructive diseases of rice. Its control through the deployment of host resistance genes would be facilitated by understanding the pathogen's race structure. Here, dynamics of race structures in this decade in Heilongjiang province were characterized by Chinese differential cultivars. Two patterns of dynamics of the race structures emerged: both race diversity and population-specific races increased gradually between 2006 and 2011, but they increased much more sharply between 2011 and 2015, with concomitant falls in both the population-common races and dominant races. Four races (ZD1, ZD3, ZD5, and ZE1) were among the top three dominant races over the whole period, indicating that the core of the race structure remained stable through this decade. On the host side, the composition of resistance in the cultivar differential set could be divided in two: the three indica-type entries of the differential set expressed a higher level of resistance to the population of M. oryzae isolates tested than did the four japonica-type entries. The cultivars Tetep and Zhenlong 13 as well as two additional resistance genes α and ε were confirmed as the most promising donors of blast resistance for the local rice improvement programs.[Formula: see text]Copyright © 2019 The Author(s). This is an open-access article distributed under the CC BY-NC-ND 4.0 International license.

3.
Biotechnol Lett ; 41(10): 1111-1119, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31428905

RESUMO

OBJECTIVE: At present, no studies have established internal control genes for circular RNA (circRNA) analyses. We aimed to identify reference circRNAs for real-time quantitative PCR (RT-qPCR). RESULTS: After analyzing the RNA-seq data, we obtained 50 circRNAs that were expressed in all samples. We ranked these 50 circRNAs according to their stability and obtained the six most stable circRNAs. We further evaluated the stability of the six circRNAs and three linear control genes (i.e., GAPDH, ß-actin and 18S rRNA) in 22 cell lines. Our results indicated that hsa_circ_0000284 (circHIPK3) and hsa_circ_0000471 (circN4BP2L2) were the two most stable genes. After removing linear RNAs or including the cells treated with Adriamycin, NH4Cl and shikonin, the two most stable genes were hsa_circ_0000471 and hsa_circ_0000284. The amplification efficiency was 100% for hsa_circ_0000471 and 95% for hsa_circ_0000284. CONCLUSIONS: In conclusion, since the stability of circRNAs is higher than that of linear RNAs, hsa_circ_0000284 and hsa_circ_0000471 may be used as reference genes not only for circRNAs but also for other kinds of RNAs. The findings in the present study fill the gap of lacking reference genes in the detection of circRNAs.

4.
Pain Res Manag ; 2019: 6760121, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31149319

RESUMO

The therapeutic goals of patients with chronic pain are not only to relieve pain but also to improve the quality of life. Chronic pain negatively affects various aspects of daily life, such as by decreasing the motivation to work and reward sensitivity, which may lead to difficulties in daily life or even unemployment. Human and animal studies have shown that chronic pain damages reward processing; the exploration of associated internal mechanisms may aid the development of treatments to repair this damage. Incentive salience theory, used widely to describe reward processing, divides this processing into "liking" (reward-induced hedonic sensory impact) and "wanting" (reward-induced motivation) components. It has been employed to explain pathological changes in reward processing induced by psychiatric disorders. In this review, we summarize the findings of studies of reward processing under chronic pain and examine the effects of chronic pain on "liking" and "wanting." Evidence indicates that chronic pain compromises the "wanting" component of reward processing; we also discuss the neural mechanisms that may mediate this effect. We hope that this review aids the development of therapies to improve the quality of life of patients with chronic pain.

6.
Sci Total Environ ; 676: 595-612, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31051366

RESUMO

Hydropower is among the most widely-adopted renewable energy sources worldwide. Its development has, however, led to environmental impacts such as carbon emissions and water loss. To date, the water footprint (WF) and carbon footprint (CF) of hydropower stations have been assessed, but not simultaneously or at a large scale such as national scale. Previous WF and CF studies rarely assessed all life-cycle stages of a hydropower station, calling for a more holistic understanding of the environmental impacts of hydropower. We developed a complete WF and CF assessment method and applied it to a case study on 50 of China's most influential hydropower stations, representing over 80% of the country's total hydropower. The total annual WF of these hydropower stations was 5.50 × 1011 m3, equal to 18.9% of Yellow River's annual runoff. The total CF of these stations was 1.06 × 107 tCO2e, with extremely large variations found, ranging from 1850 to 1.56 × 106 tCO2e. This study provides the first environmental impact assessment to simultaneously include the WF and CF of multiple influential hydropower stations at a national scale. We were able to show spatial variations in their environmental impacts from different life-cycle stages of the hydropower station. Most of the WF was due to surface water loss from reservoirs, while most of the CF was derived from the operational and maintenance stage of these stations. This initial WF and CF assessment of hydropower at a national scale provides insights for water resource management and carbon reduction during hydropower development.

7.
Clin Exp Optom ; 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31119785

RESUMO

BACKGROUND: Adequate diagnosis of acute anterior ischaemic optic neuropathy (AION) is challenging to achieve with traditional medical imaging approaches. The aim of this study was to evaluate the detection capacity of diffusion tensor imaging for abnormalities of the optic nerve in acute AION patients. METHODS: Diffusion tensor imaging data were collected from 31 patients with acute AION and 20 healthy subjects. The mean fractional anisotropy and apparent diffusion co-efficient subsequently were evaluated across all subjects. RESULTS: In affected nerves, the mean fractional anisotropy was reduced and the mean apparent diffusion co-efficient was increased in acute AION patients compared with control nerves (p < 0.001), as well as clinically unaffected contralateral nerves (p < 0.001). The mean fractional anisotropy and apparent diffusion co-efficient demonstrated no difference between normal control nerves and clinically unaffected contralateral nerves (p = 0.73 and 0.92, respectively). CONCLUSION: Diffusion tensor imaging of the optic nerves demonstrated diagnostic potential for acute AION and could serve as a novel tool for the detection and evaluation of therapies.

8.
Nat Commun ; 10(1): 2107, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-31068596

RESUMO

Aromatic N-heterocyclic compounds are very important chemicals, which are currently produced mostly from petroleum. Here we report that a pyridazine-based compound 6-(4-hydroxy-3-methoxyphenyl)pyridazin-3(2H)-one (GSPZ) can be efficiently synthesized by the Friedel-Crafts reaction of guaiacol and succinic anhydride, both of which can be derived from biomass. GSPZ is then treated with bio-based epichlorohydrin to prepare the epoxy resin precursor GSPZ-EP. With 4,4'-diaminodiphenylmethane as curing agent, GSPZ-EP possesses higher glass transition temperature (187 oC vs. 173 oC) and shows a 140%, 70 and 93% increase in char yield (in N2), storage modulus (30 oC) and Young's modulus, respectively when compared with a standard petroleum-based bisphenol A epoxy resin. Moreover, the cured GSPZ-EP shows good intrinsic flame retardancy properties and is very close to the V-0 rating of UL-94 test. This work opens the door for production of aromatic N-heterocyclic compounds, which can be derived from biomass and employed to construct high performance polymers.

9.
Blood Cells Mol Dis ; 77: 82-87, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31005751

RESUMO

Ionizing radiation (IR) causes severe damage to the hematopoietic system; thus, it is necessary to explore agents or compounds that can reduce this damage. SS31 is a mitochondria-targeted peptide that can scavenge cellular reactive oxygen species (ROS) and inhibit the production of mitochondrial ROS. Therefore, in this study, we discuss the protective effect of SS31 on IR-induced hematopoietic system damage. Our results showed that treatment with 6 mg/kg SS31 elevated the survival rate of lethally irradiated mice and increased the numbers of white blood cells, red blood cells, hemoglobin and platelets in mice exposed to 4 Gy whole-body irradiation. In addition, SS31 administration improved the number of hematopoietic stem/progenitor cells (HSPCs) and the self-renewal and reconstitution abilities of these cells in irradiated mice. The elevation of ROS levels is the main cause of IR-induced hematopoietic system damage, and SS31 can effectively reduce the ROS level in HSPCs. The above results suggest that SS31 can protect the hematopoietic system from radiation-induced damage by reducing cellular ROS levels.

10.
Biosci Rep ; 39(5)2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-30988071

RESUMO

Homo sapiens ceramide synthase 2 (CerS-2) plays an important role in inhibiting invasion and metastasis of tumor cells and has been reported as a tumor metastasis suppressor gene in diverse cancers. Thus, low level of CerS-2 protein might suggest a bad prognosis and up-regulation of CerS-2 protein might act as a promising therapeutic strategy for malignant tumors. In this review, we discussed the expression, as well as the clinical and pathological significance of CerS-2 in diverse human cancers. The pathological processes and molecular pathways regulated by CerS-2 were also summarized.

11.
Comput Biol Chem ; 80: 159-167, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30959272

RESUMO

Since the driver pathway in cancer plays a crucial role in the formation and progression of cancer, it is very imperative to identify driver pathways, which will offer important information for precision medicine or personalized medicine. In this paper, an improved maximum weight submatrix problem model is proposed by integrating such three kinds of omics data as somatic mutations, copy number variations, and gene expressions. The model tries to adjust coverage and mutual exclusivity with the average weight of genes in a pathway, and simultaneously considers the correlation among genes, so that the pathway having high coverage but moderate mutual exclusivity can be identified. By introducing a kind of short chromosome code and a greedy based recombination operator, a parthenogenetic algorithm PGA-MWS is presented to solve the model. Experimental comparisons among algorithms GA, MOGA, iMCMC and PGA-MWS were performed on biological and simulated data sets. The experimental results show that, compared with the other three algorithms, the PGA-MWS one based on the improved model can identify the gene sets with high coverage but moderate mutual exclusivity and scales well. Many of the identified gene sets are involved in known signaling pathways, most of the implicated genes are oncogenes or tumor suppressors previously reported in literatures. The experimental results indicate that the proposed approach may become a useful complementary tool for detecting cancer pathways.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas/estatística & dados numéricos , Genes Neoplásicos , Genômica/estatística & dados numéricos , Glioblastoma/genética , Neoplasias Ovarianas/genética , Algoritmos , Variações do Número de Cópias de DNA , Feminino , Expressão Gênica , Humanos , Mutação , Transdução de Sinais/genética
12.
Biosci Rep ; 39(3)2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30833362

RESUMO

Cervical cancer (CC) with early metastasis of the primary tumor results in poor prognosis and poor therapeutic outcomes. MicroRNAs (miRNAs) are small, noncoding RNA molecules that play a substantial role in regulating gene expression post-transcriptionally and influence the development and progression of tumors. Numerous studies have discovered that miRNAs play significant roles in the invasion and metastasis of CC by affecting specific pathways, including Notch, Wnt/ß-catenin, and phosphoinositide-3 kinase (PI3K)-Akt pathways. miRNAs also effectively modulate the process of epithelial-mesenchymal transition. Many studies provide new insights into the role of miRNAs and the pathogenesis of metastatic CC. In this review, we will offer an overview and update of our present understanding of the potential roles of miRNAs in metastatic CC.

13.
Epigenomics ; 11(4): 411-421, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30785332

RESUMO

AIM: We aimed to explore the roles of circular RNAs (circRNAs) in breast cancer (BCa). MATERIALS & METHODS: RNA was extracted from exosomes and BCa cells and analyzed using the RNA sequencing technique or microarray. RESULTS: Compared with controls, 1147 and 1195 circRNAs were dysregulated in exosomes from metastatic and localized BCa patients, respectively. A total of 480 dysregulated circRNAs were found in metastatic patients compared with localized patients, and these dysregulated circRNAs were enriched in eight pathways. Compared with MCF-7 cells and their exosomes, there were 5842 and 1137 dysregulated circRNAs in MDA-MB-231 cells and exosomes, respectively, and 5 circRNAs were confirmed using real-time quantitative PCR. CONCLUSION: We identified a number of dysregulated circRNAs in exosomes from BCa cells and patients.

14.
Neuropharmacology ; 148: 1-10, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30612008

RESUMO

Oscillatory activities within basal ganglia (BG) circuitry in L-DOPA induced dyskinesia (LID), a condition that occurs in patients with Parkinson disease (PD), are not well understood. The aims of this study were firstly to investigate oscillations in main BG input and output structures-the dorsolateral striatum (dStr) and substantia nigra pars reticulata (SNr), respectively- including the direction of oscillation information flow, and secondly to investigate the effects of 5-HT1A/B receptor agonism with eltoprazine on oscillatory activities and abnormal involuntary movements (AIMs) characteristic. To this end, we conducted local field potential (LFP) electrophysiology in the dStr and SNr of LID rats simultaneous with AIM scoring. The LFP data were submitted to power spectral density, coherence, and partial Granger causality analyses. AIM data were analyzed relative to simultaneous oscillatory activities, with and without eltoprazine. We obtained four major findings. 1) Theta band (5-8 Hz) oscillations were enhanced in the dStr and SNr of LID rats. 2) Theta power correlated with AIM scores in the 180-min period after the last LID-inducing L-DOPA injection, but not with daily summed AIM scores during LID development. 3) Oscillatory information flowed from the dStr to the SNr. 4) Chronic eltoprazine reduced BG theta activity in LID rats and normalized information flow directionality, relative to that in LID rats not given eltoprazine. These results indicate that dStr activity plays a determinative role in the causal interactions of theta oscillations and that serotonergic inhibition may suppress dyskinesia by reducing dStr-SNr theta activity and restoring theta network information flow.

15.
PLoS Pathog ; 15(1): e1007534, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668603

RESUMO

Tomato yellow leaf curl virus (TYLCV) and its related begomoviruses cause fast-spreading diseases in tomato worldwide. How this virus induces diseases remains largely unclear. Here we report a noncoding RNA-mediated model to elucidate the molecular mechanisms of TYLCV-tomato interaction and disease development. The circular ssDNA genome of TYLCV contains a noncoding intergenic region (IR), which is known to mediate viral DNA replication and transcription in host cells, but has not been reported to contribute directly to viral disease development. We demonstrate that the IR is transcribed in dual orientations during plant infection and confers abnormal phenotypes in tomato independently of protein-coding regions of the viral genome. We show that the IR sequence has a 25-nt segment that is almost perfectly complementary to a long noncoding RNA (lncRNA, designated as SlLNR1) in TYLCV-susceptible tomato cultivars but not in resistant cultivars which contains a 14-nt deletion in the 25-nt region. Consequently, we show that viral small-interfering RNAs (vsRNAs) derived from the 25-nt IR sequence induces silencing of SlLNR1 in susceptible tomato plants but not resistant plants, and this SlLNR1 downregulation is associated with stunted and curled leaf phenotypes reminiscent of TYLCV symptoms. These results suggest that the lncRNA interacts with the IR-derived vsRNAs to control disease development during TYLCV infection. Consistent with its possible function in virus disease development, over-expression of SlLNR1 in tomato reduces the accumulation of TYLCV. Furthermore, gene silencing of the SlLNR1 in the tomato plants induced TYLCV-like leaf phenotypes without viral infection. Our results uncover a previously unknown interaction between vsRNAs and host lncRNA, and provide a plausible model for TYLCV-induced diseases and host antiviral immunity, which would help to develop effective strategies for the control of this important viral pathogen.


Assuntos
Begomovirus/genética , RNA Longo não Codificante/genética , DNA Intergênico/genética , Inativação Gênica/fisiologia , Genoma Viral/genética , Lycopersicon esculentum/imunologia , Doenças das Plantas/genética , RNA Longo não Codificante/metabolismo , RNA Interferente Pequeno/genética
16.
Epigenomics ; 11(2): 199-213, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30657346

RESUMO

AIM: The study aimed to investigate the role of circular RNA circASS1 in breast cancer cells. MATERIALS & METHODS: Circular RNAs microarray expression profile were analyzed in MCF-7, MDA-MB-231, and qRT-PCR and western blotting were used to quantify expression of circASS1 and its parental gene ASS1. Wound healing, migration and invasion assay were performed. Luciferase assay system was used to detect harbored miRNA. RESULTS: CircASS1 in MDA-MB-231 is downregulated comparing to MCF-7, and overexpression of circASS1 could suppress invasion and migration. While silence, it could promote invasion and migration. MiR-4443 functioning as a tumor promoter gene could be captured by circASS1. ASS1 is upregulated in loss-of-function experiments, while downregulated in gain-of-function experiments. CONCLUSION: CircASS1 suppresses invasion and migration capacity of breast cancer cells and harbored miR-4443.

17.
Clin Chim Acta ; 490: 17-27, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30553863

RESUMO

Ovarian cancer is one of the most common gynecologic malignancies and has a poor prognosis. Recently, long noncoding RNAs (lncRNAs) have been identified as key regulators of cancer development. Studies have shown that the dysregulation of lncRNAs is frequently observed in ovarian cancer and greatly contributes to malignant phenotypical changes. In this review, we provide perspectives on the involvement of lncRNAs in the proliferation, apoptosis, cell cycle, migration, invasion, metastasis and drug resistance of ovarian cancer based on recent discoveries. Then, we discuss the role of lncRNAs in predicting the prognosis of ovarian cancer. Finally, we provide insight into the potential of lncRNAs for evaluating the diagnosis and prognosis of ovarian cancer.


Assuntos
Neoplasias Ovarianas/genética , RNA Longo não Codificante/genética , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia
18.
Sci Rep ; 8(1): 15673, 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30353114

RESUMO

Pain, especially chronic pain, can lead to cognitive deficits. Mismatch negativity (MMN) is a change-specific component of the auditory event-related brain potential (ERP) that is thought to provide a unique window into sensory memory processes. The present study was designed to determine how chronic and acute pain affects auditory sensory memory. In experiment 1, MMNs elicited by standard and deviant auditory stimuli at short and long inter-stimulus intervals (ISIs) were compared between trigeminal neuralgia (TN) patients and demographically matched healthy controls (HCs). The TN patients were found to have stronger attenuation of the MMN at longer ISIs than HCs. Correlation analysis revealed a significant positive correlation between the sensory subscale of McGill Pain Questionnaire and MMN amplitude reduction across ISI conditions. In experiment 2, MMNs recorded before, during, and after the cold pressor test were compared in healthy subjects. MMN amplitude was significantly reduced during pain exposure and recovered immediately thereafter. These results suggest that both chronic pain and acute pain can interfere with automatic change detection processes in the brain. This study provides the first evidence that chronic pain patients have a faster auditory memory trace decay than HCs.

19.
Breast Cancer ; 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30341748

RESUMO

BACKGROUND: We aimed to investigate the potential of microRNA expression profiles to predict survival in breast cancer. METHODS: MicroRNA and mRNA expression data of breast cancer were downloaded from The Cancer Genome Atlas. LASSO regression was used to identify microRNAs signature predicting survival of breast cancer patients. Transfection experiment was conducted to explore the influence of microRNAs on their potential targets. RESULTS: We identified 56 differentially expressed microRNAs in breast cancer tissues compared to adjacent normal tissues. 10 microRNAs with non-zero coefficient were selected from the 56 microRNAs using LASSO Cox regression. After predicting the targets for the 10 microRNAs, we further obtained 155 targets that were associated with overall survival of breast cancer patients. Spearman's correlation analysis found that the expression of SCUBE2, SCRN3, YTHDF3, ITFG1, ITPRIPL2, and JAK1 was an inversely correlated with their microRNAs. Transfection experiment showed that YTHDF3 was down-regulated in cells transfected with miR-106b-5p mimics compared with those transfected with negative control of mimics (fold change 4.21; P < 0.01). CONCLUSIONS: In conclusion, we identified a 10-miRNA signature associated with prognosis of breast cancer patients. The expression of YTHDF3 was down-regulated by miR-106b-5p.

20.
Epigenomics ; 10(11): 1499-1509, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30309258

RESUMO

Exosomes are small membrane vesicles with a diameter of 40-100 nm, which are released into the intracellular environment. Exosomes could influence the genetic and epigenetic changes of receptor cells by promoting the horizontal transfer of various proteins or RNAs, especially miRNAs. Moreover, exosomes also play an important role in tumor microenvironment. Exosomes could promote the short- and long-distance exchanges of genetic information by acting as mediators of cell-to-cell communication. In addition, exosomes participate in drug resistance of tumor cells by genetic exchange between cells. It is reported that exosomes could be absorbed by recipient cells and transmit chemoresistance from drug-resistant tumor cells to sensitive ones. Then understanding the mechanisms of chemotherapy failure and controlling tumor progression effectively will be a major challenge for us. Therefore, in this review, we will briefly reveal the role of exosomes in drug resistance.

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