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1.
J Nanosci Nanotechnol ; 20(2): 828-839, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383078

RESUMO

At present, high-performance cement-based composites are widely used, and they are prone to early cracking due to their high autogenous shrinkage stress. In this research, the uniformly dispersed GNPs were added into high-performance cementitious materials. The autogenous shrinkage of high-performance cementitious matrix materials with different incorporation of GNPs was also researched with water to cement ratio of 0.25, 0.30 and 0.35. According to hydration heat, hydration products, microstructure and porosity of GNPs cementitious matrix materials, the microcosmic mechanism for autogenous shrinkage was also investigated. It was testified that moderate addition of GNPs decreased the autogenous shrinkage of cement-based composites. Moreover, the autogenous shrinkage value was minimal after treatment with 0.10 wt% GNPs cement paste sample for 7 days, at the water to cement ratio of 0.35, and the depressed percentage of autogenous shrinkage reached 81.60% compared with the blank sample.

2.
J Chromatogr A ; : 460472, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31471136

RESUMO

Pomegranate flowers is an ancient medicine that has commonly been used to treat various diseases such as diabetes. However, no reports are available on the metabolic profile of pomegranate flowers in vivo. In the present study, with the aid of HPLC-Q-TOF-MS2, 67 compounds were identified in pomegranate flowers extract, including 18 ellagitannins, 14 gallic acid and galloyl derivatives, five anthocyanins and 18 flavonoids. Seven compounds were firstly identified. In vivo, 22 absorbed compounds and 35 metabolites were identified in rat biosamples (urine, feces, plasma and tissues) after orally administered with pomegranate flowers extract. This result showed that not all compounds abundant in pomegranate flowers extract could be absorbed well in plasma and tissues. This finding also suggested a potential correlation between study on metabolic profile of these compounds in vivo and study on strategy of screening bioactivity of the isolates with in vitro cell systems evaluation. Notably, mono-glucuronide conjugated metabolite of ellagitannin compound (corilagin) was firstly identified. In addition, this is first report to identify phase II conjugate metabolites of ellagitannins in vivo after oral administration of ellagitannins-rich extracts (or foods). Thus, characterizing its multiple constitution, absorption and metabolic fate of these compounds in vivo is helpful to better analyze the active components in pomegranate flowers.

3.
Sci Rep ; 9(1): 12612, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31471555

RESUMO

Ocular trauma is a major cause of monocular blindness worldwide. Vitrectomy at correct timing can significantly improve the efficacy and prognosis, but the timing of vitrectomy has remained highly controversial for decades. Trauma cases are different from each other, thus, a flexible timing system based on the details of each individual case is recommended. Unfortunately, no such a timing system is available for clinical application up to now. To establish the vitrectomy timing individualization system for ocular trauma (VTISOT), we first identified 6 independent tPVR risk factors (including Zone 3 Injury, Zone 3 retinal Laceration, Massive Vitreous Hemorrhage, Retinal Disorder, Timing of Vitrectomy and Type of Injury) by retrospective study. Then, the tPVR score was established by binary logistic regression analysis. Most importantly and critically, the vitrectomy timing individualization system for ocular trauma was established based on the identified tPVR risk factors and the tPVR score. The following evaluation of the VTISOT showed that the patients consistent with the VTISOT principles exhibited reduced tPVR incidence and better surgical results. In short, the VTISOT principles were established, which may provide a new approach to individualize the timing of vitrectomy and improve the prognosis after trauma.

4.
Aging (Albany NY) ; 112019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477637

RESUMO

OBJECTIVES: Autophagy is an evolutionarily conserved intracellular degradation mechanism in which cell constituents are phagocytosed to maintain cellular homeostasis. Forkhead box O 3a (FoxO3a) promotes autophagy to protect cells from environmental stress. Methylated CpG binding protein 2 (MeCP2) is a nuclear protein that binds DNA and represses transcription. However, the mechanism and interplay between FoxO3a and MeCP2 underlying endothelial progenitor cell (EPC) function are not fully understood. RESULTS: In EPCs, MeCP2 overexpression attenuated autophagy and cell functionality, which were reversed by the autophagy activator rapamycin or co-transfection with FoxO3a. FoxO3a promoted cell function, which was reversed by the autophagy inhibitor chloroquine. Following MeCP2 overexpression, MeCP2 was found enriched on the FoxO3a promoter, resulting in promoter hypermethylation and enhanced H3K9 histone modification in nucleosomes of the FoxO3a promoter. CONCLUSIONS: MeCP2 attenuated cell functionality via DNA hypermethylation and histone modification of the FoxO3a promoter to inhibit FoxO3a transcription and autophagy. MATERIALS AND METHODS: EPCs were isolated from human umbilical cord blood and treated with adenoviral vectors containing interference sequences. The effects and mechanism of MeCP2 and FoxO3a were analyzed by utilizing western blotting, cell counting kit-8, transwell plates, Matrigel, matrix adhesion, transmission electron microscopy, and chromatin immunoprecipitation.

5.
PLoS One ; 14(9): e0221271, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31479453

RESUMO

Identification of the most influential spreaders that maximize information propagation in social networks is a classic optimization problem, called the influence maximization (IM) problem. A reasonable diffusion model that can accurately simulate information propagation in social networks is the key step to efficiently solving the IM problem. Synergism of neighbor nodes plays an important role in information propagation dynamics. Some known diffusion models have considered the reinforcement mechanism in defining the activation threshold. Most of these models focus on the synergetic effects of nodes on their common neighbors, but the accumulation of synergism has been neglected in previous studies. Inspired by these facts, we first discuss the catalytic role of synergism in the spreading dynamics of social networks and then propose a novel diffusion model called the synergism-based three-step cascade model (TSSCM) based on the above analysis and the three-degree influence theory. Finally, we devise an algorithm for solving the IM problem based on the TSSCM. Experiments on five real large-scale social networks demonstrate the efficacy of our method, which achieves competitive results in terms of influence spreading compared to the four other algorithms tested.

6.
Foodborne Pathog Dis ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483172

RESUMO

Chlorogenic acid (CA), an ester of caffeic acid, is a major phenolic compound in herbs. The antimicrobial activity of CA against Pseudomonas aeruginosa P1, a foodborne pathogen, was investigated in this study. To understand how CA injured target cells, the influence of CA on cell morphology was assessed. A sunken cell surface and detachment of outer membrane components in P. aeruginosa P1 were observed after being treated by CA. Following this, the intracellular membrane permeability and the content of lipopolysaccharide (LPS), a main component of outer membrane, were determined. The release of intracellular protein and ATP from P. aeruginosa P1 indicated that CA increased intracellular membrane permeability and resulted in the leakage of intracellular materials. The uptake of propidium iodide, a compromised cell membrane nucleic acid stain, further demonstrated that CA acted on the intracellular membrane. CA resulted in the decrease of LPS contents of P. aeruginosa P1, which supported the detachment of outer membrane. CA also downregulated the expression of major genes in LPS biosynthesis, suggesting that CA may inhibit intracellular metabolism of P. aeruginosa P1 cells. Thus, CA increased the intracellular membrane permeability, induced the exfoliation of outer membrane, and disturbed the intracellular metabolism. Damage of intracellular and outer membranes as well as disruption of cell metabolism resulted in cell death eventually. The finding suggested that CA has the potential to be developed as a preservative to control P. aeruginosa-associated foodborne diseases.

7.
BMC Microbiol ; 19(1): 201, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477026

RESUMO

BACKGROUND: Plants have evolved intimate interactions with soil microbes for a range of beneficial functions including nutrient acquisition, pathogen resistance and stress tolerance. Further understanding of this system is a promising way to advance sustainable agriculture by exploiting the versatile benefits offered by the plant microbiome. The rhizosphere is the interface between plant and soil, and functions as the first step of plant defense and root microbiome recruitment. It features a specialized microbial community, intensive microbe-plant and microbe-microbe interactions, and complex signal communication. To decipher the rhizosphere microbiome assembly of soybean (Glycine max), we comprehensively characterized the soybean rhizosphere microbial community using 16S rRNA gene sequencing and evaluated the structuring influence from both host genotype and soil source. RESULTS: Comparison of the soybean rhizosphere to bulk soil revealed significantly different microbiome composition, microbe-microbe interactions and metabolic capacity. Soil type and soybean genotype cooperatively modulated microbiome assembly with soil type predominantly shaping rhizosphere microbiome assembly while host genotype slightly tuned this recruitment process. The undomesticated progenitor species, Glycine soja, had higher rhizosphere diversity in both soil types tested in comparison to the domesticated soybean genotypes. Rhizobium, Novosphingobium, Phenylobacterium, Streptomyces, Nocardioides, etc. were robustly enriched in soybean rhizosphere irrespective of the soil tested. Co-occurrence network analysis revealed dominant soil type effects and genotype specific preferences for key microbe-microbe interactions. Functional prediction results demonstrated converged metabolic capacity in the soybean rhizosphere between soil types and among genotypes, with pathways related to xenobiotic degradation, plant-microbe interactions and nutrient transport being greatly enriched in the rhizosphere. CONCLUSION: This comprehensive comparison of the soybean microbiome between soil types and genotypes expands our understanding of rhizosphere microbe assembly in general and provides foundational information for soybean as a legume crop for this assembly process. The cooperative modulating role of the soil type and host genotype emphasizes the importance of integrated consideration of soil condition and plant genetic variability for future development and application of synthetic microbiomes. Additionally, the detection of the tuning role by soybean genotype in rhizosphere microbiome assembly provides a promising way for future breeding programs to integrate host traits participating in beneficial microbiota assembly.

8.
J Am Chem Soc ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31475527

RESUMO

Pyrimidines are almost unreactive partners in Diels-Alder cycloadditions with alkenes and alkynes, and only reactions under drastic conditions have previously been reported. We describe how 2-hydrazonylpyrimidines, easily obtained in two steps from commercially available 2-halopyrimidines, can be exceptionally activated by trifluoroacetylation. This allows a Diels-Alder cycloaddition under very mild reaction conditions, leading to a large diversity of aza-indazoles, a ubiquitous scaffold in medicinal chemistry. This reaction is general and scalable and has an excellent functional group tolerance. A straightforward synthesis of a key intermediate of Bayer's Vericiguat illustrates the potential of this cycloaddition strategy. Quantum mechanical calculations show how the simple N-trifluoroacetylation of 2-hydrazonylpyrimidines distorts the substrate into a transition-state-like geometry that readily undergoes the intramolecular Diels-Alder cycloaddition.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31487151

RESUMO

Magnetic ferroferric oxide-supported bimetallic Pd-In cluster sub-nanoparticles were used for the first time for the catalytic reduction of nitrates. Due to the unique properties of the FeOx support, the PdIn active centers could be highly dispersed in both nano- and sub-nanoscales. A variety of characterizations and the charge density difference model confirm that a strong metal-support interaction exists between the active sites and the support. The PdIn nanoparticles on FeOx show high selectivity toward nitrogen and excellent cyclic activity due to ferromagnetism, which broaden its prospect in practical water treatment. Moreover, the active centers in the sub-nanoscale are used in the nitrate reduction process for the first time and they show a distinct higher activity in denitration. The rate constant for nitrate conversion on PdIn sub-nanoparticles is larger than that for its nanometer counterpart based on the Langmuir-Hinshelwood model. High turnover frequency value and ammonia selectivity are achieved for the small-sized sub-nanocatalyst. The FeOx-supported PdIn nanoparticles and sub-nanoparticles have two application areas in water purification and ammonia recovery, respectively. Density functional theory calculations on the adsorption energies of elemental reactions are also performed, which shed some light on the catalysis mechanism and catalyst design.

10.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(9): 890-893, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31506148

RESUMO

OBJECTIVE: To study the long-term clinical effect of the CCLG-ALL2008 regimen in the treatment of children newly diagnosed with acute lymphoblastic leukemia (ALL) with different molecular biological features. METHODS: A total of 940 children who were newly diagnosed with ALL were enrolled in this study. The children were treated with the CCLG-ALL2008 regimen. A retrospective analysis was performed for the long-term outcome of ALL children with different molecular biological features. RESULTS: Among the 940 children with ALL, there were 570 boys and 370 girls, with a median age of onset of 5 years (range 1-15 years) and a median follow-up time of 65 months (range 3-123 months). The complete response (CR) rate was 96.7%, the predicted 10-year overall survival (OS) rate was 76.5%±1.5%, and the event-free survival (EFS) rate was 62.6%±3.0%. After CR was achieved after treatment, the overall recurrence rate was 21.9%. The children with positive ETV6-RUNX1 had the lowest recurrence rate and were prone to late recurrence, and those with positive MLL rearrangement had the highest recurrence rate and were prone to early recurrence. The children with positive ETV6-RUNX1 had a significantly higher predicted 10-year OS rate than those with positive TCF3-PBX1, BCR-ABL, or MLL rearrangement and those without molecular biological features (P<0.05). The children with positive ETV6-RUNX1 had a significantly higher predicted 10-year EFS rate than those with positive BCR-ABL or MLL rearrangement (P<0.05). CONCLUSIONS: Molecular biological features may affect the long-term prognosis of children with ALL, and positive MLL rearrangement and BCR-ABL fusion gene are indicators of poor prognosis. Children with positive ETV6-RUNX1 fusion gene have the highest long-term survival rate.

11.
Mol Genet Genomic Med ; : e923, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503426

RESUMO

BACKGROUND: Pediatric myelodysplastic syndromes (MDS) display clonal genomic instability that can lead to acquisition of other hematological disorders, usually by loss of heterozygosity. Immunodeficiency caused by uniparental disomy (UPD) has not previously been reported. METHODS: We investigated a 13-year-old boy who suffered from recurrent infections and pancytopenia for 1 year. Both the comet assay and chromosome breakage analysis were normal, but the bone marrow showed evidence of dysplasia characteristic of MDS. With his normal sister as donor, he underwent failed hematopoietic stem cell transplantation (HSCT) with reduced intensity conditioning (RIC) followed by successful HSCT with myeloablative conditioning (MAC). We used single nucleotide polymorphism (SNP) array, targeted gene panel, and whole exome sequencing to investigate the etiology of his disease. RESULTS: The molecular analyses revealed multiple regions of homozygosity, one region encompassing a homozygous missense variant of recombination activating gene 1 (RAG1) which was previously associated with severe immunodeficiency in infancy. This RAG1 mutation was heterozygous in the proband's fingernail DNA, but was changed to homozygous in the proband's marrow by somatic acquisition of UPD event. No other pathogenic driver mutation for MDS-related genes was identified. CONCLUSION: The hematological phenotype, somatic genomic instability, and response to HSCT MAC but not HSCT RIC deduced to a diagnosis of MDS type refractory cytopenia of children in this patient. His immunodeficiency was secondary to MDS due to somatic acquisition of homozygosity for known pathogenic RAG1 mutation.

12.
Medicine (Baltimore) ; 98(37): e17157, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31517862

RESUMO

Antimicrobial resistance, a major threat to human health, is mainly driven by the overuse of antimicrobials. The purpose of this study was to further investigate the relationship between antimicrobial use and resistance with a 15-year record in Southwest hospital, one of the largest hospitals in Southwest China and a university affiliated hospital, thus to further predict the antimicrobial resistance in an autoregressive integrated moving average (ARIMA) manner. Kirby-Bauer tests were carried out to figure out the drug sensitivity of Gram-negative bacterial. Antimicrobials (ß-lactamase inhibitor complex, aminoglycosides, quinolones, third and fourth-generation cephalosporins, carbapenems, cephamycins, oxacephems, and sulfonamides) consumption were calculated according to World Health Organization (WHO) anatomical therapeutic chemical classification index and expressed as annual defined daily dose (DDD) or DDD per 1000 out patients. Resistance rates of levofloxacin-resistant Escherichia coli, ceftazidime-resistant Klebsiella pneumoniae, amikacin-resistant Bacterium levans, imipenem-resistant Pseudomonas aeruginosa is positively correlated with the usage of aminoglycosides and quinolones; resistance rates of imipenem-resistant Acinetobacter baumanii is positively correlated with the usage of carbapenemes (P-value between the drug resistance of levofloxacin-resistant E. coli, ceftazidime-resistant K. pneumoniae and the usage of aminoglycosides is under .05, the other P-value are under .01); resistance rates of the drug resistance of levofloxacin-resistant E. coli is positively correlated with the usage of oxacephems (P < .01); resistance rates of imipenem-resistant P. aeruginosa is positively correlated with the usage of oxacephems and sulfonamides (P < .01).The present study presents one of the largest and longest retrospective analyses in China between antimicrobial consumption and antimicrobial resistance. Change of the usage of several antibacterial drugs has great influence on the drug resistance of Gram-negative bacterial. Of particular, ARIMA forecasting revealed that carbapenem related bacterial resistance should be closely watched.

13.
EBioMedicine ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31492563

RESUMO

BACKGROUND: The gut microbiota plays important roles in modulating host metabolism. Previous studies have demonstrated differences in the gut microbiome of T2D and prediabetic individuals compared to healthy individuals, with distinct disease-related microbial profiles being reported in groups of different age and ethnicity. However, confounding factors such as anti-diabetic medication hamper identification of the gut microbial changes in disease development. METHOD: We used a combination of in-depth metagenomics and metaproteomics analyses of faecal samples from treatment-naïve type 2 diabetic (TN-T2D, n = 77), pre-diabetic (Pre-DM, n = 80), and normal glucose tolerant (NGT, n = 97) individuals to investigate compositional and functional changes of the gut microbiota and the faecal content of microbial and host proteins in Pre-DM and treatment-naïve T2D individuals to elucidate possible host-microbial interplays characterizing different disease stages. FINDINGS: We observed distinct differences characterizing the gut microbiota of these three groups and validated several key features in an independent TN-T2D cohort. We also demonstrated that the content of several human antimicrobial peptides and pancreatic enzymes differed in faecal samples between three groups. INTERPRETATION: Our findings suggest a complex, disease stage-dependent interplay between the gut microbiota and the host and point to the value of metaproteomics to gain further insight into interplays between the gut microbiota and the host. FUND: The study was supported by the National Natural Science Foundation of China (No. 31601073), the National Key Research and Development Program of China (No. 2017YFC0909703) and the Shenzhen Municipal Government of China (No. JCYJ20170817145809215). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

14.
J Electrocardiol ; 57: 63-68, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514014

RESUMO

BACKGROUND AND AIM: Migraine patients can exhibit autonomic dysregulation, in turn leading to cardiac conduction and repolarization abnormalities. This systematic review and meta-analysis evaluated the electrocardiographic changes in migraineurs. METHOD: PubMed and Embase databases were searched for human studies using the search terms 'migraine' and 'electrocardiogram' until 15th December 2018, identifying 108 and 131 studies. RESULTS: Thirteen studies involving 667 migraineurs and 208 normal subjects included (mean age=30.7, total male percentage=19.8%) were included. A longer mean QTc interval (standard mean difference=7.89, 95% confidence interval=[3.29, 12.49], p=0.0008) and higher frequency of QTc prolongation (risk ratio [RR]=6.23, [2.86-13.58], p<0.00001), but no difference in PR-interval (SMD=4.33, [-3.90-12.56], p=0.30) were observed during migraine attacks compared to pain-free periods. P-wave dispersion was higher in migraine patients compared to controls (mean difference=3.62, [1.03-6.21], p=0.006). RR-interval were statistically indistinguishable between migraine patients and controls (SMD=0.08, [-0.65-0.81], p=0.83), or between migraineurs with and without aura (SMD=-0.03, [-0.44-0.38], p=0.89). Deep breathing ratio was significantly lower in migraineurs compared to controls (SMD=-0.27, 95% CI=[-0.46, -0.08], p=0.006) but similar between migraineurs with and without aura (SMD=-0.04, [-0.27-0.19], p=0.74). No significant difference in Valsalva ratio is found between migraineurs and controls (SMD=0.10, [-0.32-0.53], p=0.63) or between migraineurs with and without aura (SMD=-0.17, [-0.40-0.06], p=0.14). Root mean square of successive differences (RMSSD) (SMD=-0.07, [-1.10-0.95], p=0.89) and standard deviation of NN intervals (SDNN) (SMD=-0.10, [-0.61-0.41], p=0.71) did not significantly differ between migraine patients and controls. CONCLUSION: Electrocardiographic alterations are observed in migraine patients compared to controls, especially during migraine attacks.

15.
BMC Infect Dis ; 19(1): 771, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481053

RESUMO

BACKGROUND: Although worldwide measles elimination achieved great progress for decades, outbreaks were still reported in certain countries. This study describes the epidemiologic features of a substantial measles outbreak in an office building in Beijing and explores control strategies in a crowded city. METHODS: We performed descriptive analyses of data on demographic characteristic, laboratory testing and epidemiological information. RESULTS: From February 25 to March 28, 2016, 43 outbreak-related measles cases occurred in an office building in Beijing. The total crude attack rate was 1.20% in the building. The age range of patients was 23 to 45 years old, of whom 30 (69.8%) were migrants and 5 (11.6%) were vaccinated but without documentation. The attack rate of the department and the company of the source case was 22.73 and 11.86%, respectively. The attack rate in the building was 1.78%, except for the commercial center on the lower floors, which was 0.34%. Of the 43 measles cases, only 19 cases (53.5%) were reported by hospitals through the National Notifiable Disease Reporting System (NNDRS), and the rest were found through active surveillance. Outbreak response immunization was conducted for 6216 persons. CONCLUSIONS: Office buildings in crowded metropolis are prone to large-scale measles outbreaks, and require a rapid outbreak response. Early Outbreak response immunization and active surveillance are important strategies to control outbreaks such as the one reported herein.

16.
Opt Express ; 27(15): 20282-20289, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510125

RESUMO

A 208 W all-solid-state modulated-longitudinal-mode quasi-continuous-wave sodium guide star (SGS) laser was developed by sum-frequency of a 1064 nm laser and a 1319 nm laser. The laser contained two spectral lines separated by 1.72 GHz for re-pumping the sodium atoms. To suppress absorption saturation effect of the sodium atoms induced by the high light intensity, we used a white noise generator to modulate the 1064 nm single frequency seed laser in the frequency domain. The line width of the modulated-longitudinal-mode 589 nm laser was maximally broadened to 0.74 GHz compared to the initial line width of ~0.30 GHz. A bright SGS with photon return flux of 56800 photons/s/cm2 during the pulse length was obtained.

17.
Opt Express ; 27(16): 22053-22073, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510501

RESUMO

Two properly designed columns of orthogonally tilted and spatially varied nano-apertures have been demonstrated to achieve polarization-controlled launching of the localized cosine-Gauss beam, which is a kind of highly localized surface plasmonic wave without diffraction. According to the experimental results, the generated unidirectional propagating plasmonic beam could propagate with a non-diffracting length of up to 57µm as well as the extinction ratio of more than 150. We believe that our proposed device would play an important role in highly compact photonic circuit on-chip with plasmonic wave.

18.
Plant Biotechnol J ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31479566

RESUMO

The diploid wild cotton species Gossypium australe possesses excellent traits including resistance to disease and delayed gland morphogenesis, and has been successfully used for distant breeding programmes to incorporate disease resistance traits into domesticated cotton. Here, we sequenced the G. australe genome by integrating PacBio, Illumina short read, BioNano (DLS) and Hi-C technologies, and acquired a high-quality reference genome with a contig N50 of 1.83 Mb and a scaffold N50 of 143.60 Mb. We found that 73.5% of the G. australe genome is composed of various repeat sequences, differing from those of G. arboreum (85.39%), G. hirsutum (69.86%) and G. barbadense (69.83%). The G. australe genome showed closer collinear relationships with the genome of G. arboreum than G. raimondii and has undergone less extensive genome reorganization than the G. arboreum genome. Selection signature and transcriptomics analyses implicated multiple genes in disease resistance responses, including GauCCD7 and GauCBP1, and experiments revealed induction of both genes by Verticillium dahliae and by the plant hormones strigolactone (GR24), salicylic acid (SA) and methyl jasmonate (MeJA). Experiments using a Verticillium-resistant domesticated G. barbadense cultivar confirmed that knockdown of the homologues of these genes caused a significant reduction in resistance against Verticillium dahliae. Moreover, knockdown of a newly identified gland-associated gene GauGRAS1 caused a glandless phenotype in partial tissues using G. australe. The G. australe genome represents a valuable resource for cotton research and distant relative breeding as well as for understanding the evolutionary history of crop genomes.

19.
Magn Reson Med ; 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31400028

RESUMO

PURPOSE: To propose a highly accelerated, high-resolution dynamic contrast-enhanced MRI (DCE-MRI) technique called GRASP-Pro (golden-angle radial sparse parallel imaging with imProved performance) through a joint sparsity and self-calibrating subspace constraint with automated selection of contrast phases. METHODS: GRASP-Pro reconstruction enforces a combination of an explicit low-rank subspace-constraint and a temporal sparsity constraint. The temporal basis used to construct the subspace is learned from an intermediate reconstruction step using the low-resolution portion of radial k-space, which eliminates the need for generating the basis using auxiliary data or a physical signal model. A convolutional neural network was trained to generate the contrast enhancement curve in the artery, from which clinically relevant contrast phases are automatically selected for evaluation. The performance of GRASP-Pro was demonstrated for high spatiotemporal resolution DCE-MRI of the prostate and was compared against standard GRASP in terms of overall image quality, image sharpness, and residual streaks and/or noise level. RESULTS: Compared to GRASP, GRASP-Pro reconstructed dynamic images with enhanced sharpness, less residual streaks and/or noise, and finer delineation of the prostate without prolonging reconstruction time. The image quality improvement reached statistical significance (P < 0.05) in all the assessment categories. The neural network successfully generated contrast enhancement curves in the artery, and corresponding peak enhancement indexes correlated well with that from the manual selection. CONCLUSION: GRASP-Pro is a promising method for rapid and continuous DCE-MRI. It enables superior reconstruction performance over standard GRASP and allows reliable generation of artery enhancement curve to guide the selection of desired contrast phases for improving the efficiency of GRASP MRI workflow.

20.
Sci Signal ; 12(593)2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31387938

RESUMO

Disruption of γ-aminobutyric acid (GABA)-ergic interneuron migration is implicated in various neurodevelopmental disorders, including autism spectrum disorder and schizophrenia. The dopamine D1 receptor (D1R) promotes GABAergic interneuron migration, which is disrupted in various neurological disorders, some of which are also associated with mutations in the gene encoding synaptic Ras-guanosine triphosphatase-activating protein (SynGAP). Here, we explored the mechanisms underlying these associations and their possible connection. In prenatal mouse brain tissue, we found a previously unknown interaction between the D1R and SynGAP. This D1R-SynGAP interaction facilitated D1R localization to the plasma membrane and promoted D1R-mediated downstream signaling pathways, including phosphorylation of protein kinase A and p38 mitogen-activated protein kinase. These effects were blocked by a peptide (TAT-D1Rpep) that disrupted the D1R-SynGAP interaction. Furthermore, disrupting this complex in mice during embryonic development resulted in pronounced and selective deficits in the tangential migration of GABAergic interneurons, possibly due to altered actin and microtubule dynamics. Our results provide insights into the molecular mechanisms regulating interneuron development and suggest that disruption of the D1R-SynGAP interaction may underlie SYNGAP1 mutation-related neurodevelopmental disorders.

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