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1.
JAMA Psychiatry ; 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31851304

RESUMO

Importance: Alcohol abuse correlates with gray matter development in adolescents, but the directionality of this association remains unknown. Objective: To investigate the directionality of the association between gray matter development and increase in frequency of drunkenness among adolescents. Design, Setting, and Participants: This cohort study analyzed participants of IMAGEN, a multicenter brain imaging study of healthy adolescents in 8 European sites in Germany (Mannheim, Dresden, Berlin, and Hamburg), the United Kingdom (London and Nottingham), Ireland (Dublin), and France (Paris). Data from the second follow-up used in the present study were acquired from January 1, 2013, to December 31, 2016, and these data were analyzed from January 1, 2016, to March 31, 2018. Analyses were controlled for sex, site, socioeconomic status, family history of alcohol dependency, puberty score, negative life events, personality, cognition, and polygenic risk scores. Personality and frequency of drunkenness were assessed at age 14 years (baseline), 16 years (first follow-up), and 19 years (second follow-up). Structural brain imaging scans were acquired at baseline and second follow-up time points. Main Outcomes and Measures: Increases in drunkenness frequency were measured by latent growth modeling, a voxelwise hierarchical linear model was used to observe gray matter volume, and tensor-based morphometry was used for gray matter development. The hypotheses were formulated before the data analyses. Results: A total of 726 adolescents (mean [SD] age at baseline, 14.4 [0.38] years; 418 [58%] female) were included. The increase in drunkenness frequency was associated with accelerated gray matter atrophy in the left posterior temporal cortex (peak: t1,710 = -5.8; familywise error (FWE)-corrected P = 7.2 × 10-5; cluster: 6297 voxels; P = 2.7 × 10-5), right posterior temporal cortex (cluster: 2070 voxels; FWE-corrected P = .01), and left prefrontal cortex (peak: t1,710 = -5.2; FWE-corrected P = 2 × 10-3; cluster: 10 624 voxels; P = 1.9 × 10-7). According to causal bayesian network analyses, 73% of the networks showed directionality from gray matter development to drunkenness increase as confirmed by accelerated gray matter atrophy in late bingers compared with sober controls (n = 20 vs 60; ß = 1.25; 95% CI, -2.15 to -0.46; t1,70 = 0.3; P = .004), the association of drunkenness increase with gray matter volume at age 14 years (ß = 0.23; 95% CI, 0.01-0.46; t1,584 = 2; P = .04), the association between gray matter atrophy and alcohol drinking units (ß = -0.0033; 95% CI, -6 × 10-3 to -5 × 10-4; t1,509 = -2.4; P = .02) and drunkenness frequency at age 23 years (ß = -0.16; 95% CI, -0.28 to -0.03; t1,533 = -2.5; P = .01), and the linear exposure-response curve stratified by gray matter atrophy and not by increase in frequency of drunkenness. Conclusions and Relevance: This study found that gray matter development and impulsivity were associated with increased frequency of drunkenness by sex. These results suggest that neurotoxicity-related gray matter atrophy should be interpreted with caution.

2.
Schizophr Res ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31706787

RESUMO

The neurobiological heterogeneity of schizophrenia is widely accepted, but it is unclear how mechanistic differences converge to produce the observed phenotype. Establishing a pathophysiological model that accounts for both neurobiological heterogeneity and phenotypic similarity is essential to inform stratified treatment approaches. In this cross-sectional diffusion tensor imaging study, we recruited 77 healthy controls, and 70 patients with DSM-IV diagnosis of schizophrenia. We first confirmed the heterogeneity in structural connectivity by showing a reduced between-individual similarity of the structural connectivity in patients compared to healthy controls. Second, at a system level, we found the diversity of the topographic distribution of the strength of structural connectivity was significantly reduced in patients (P = 7.21 × 10-7, T142 = 5.19 [95% CI: 3.37-7.52], Cohen's d = 0.91), and this affected 65 of the 90 brain regions examined (False Discovery Rate <5%). Third, when topographic diversity was used as a discriminant feature to train a model for classifying patients from controls, it significantly improved the accuracy on an independent sample (T99 = 5.54; P < 0.001). These findings suggest a highly individualized pattern of structural dysconnectivity underlies the heterogeneity of schizophrenia, but these disruptions likely converge on an emergent common pathway to generate the clinical phenotype of the disorder.

3.
Zootaxa ; 4646(1): zootaxa.4646.1.9, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31717032

RESUMO

Two new leafhopper species of the bamboo-feeding subgenus Myittana (Benglebra), M. (Benglebra) biflaka sp. nov. and M. (Benglebra) curvata sp. nov. are described and illustrated from the southwest of China (Yunnan Province). A new combination, M. (Benglebra) ventrospina (Chen Yang, 2007), comb. nov. is proposed. Female genitalia of four Chinese species are described and illustrated for the first time. A key to all known species is also provided.


Assuntos
Hemípteros , Animais , China , Feminino
4.
Int J Biol Macromol ; 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31770558

RESUMO

Chitosan-α-lipoic acid (CS-LA) conjugates were prepared by amino reaction. The methotrexate (MTX) was successfully loaded within CS-LA copolymer by the ring-opening polymerizations of disulfide bond under the action of reducing agent. The obtained copolymer was investigated by fourier transform infrared spectrometer (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and nuclear magnetic resonance (1H NMR) analysis. The ring-opening polymerization process effects on rheological properties were studied. The graft of LA increased the apparent viscosity of CS-LA, and the loaded of MTX by redox reduced its apparent viscosity enormously. The load of MTX under the action of DTT decreased the apparent viscosity and moduli of CS-LA-MTX hydrogel. In dynamic oscillatory experiment, the package of MTX reduced the rigidity of CS-LA and damaged the gel structure of CS-LA. The antimicrobial ability of CS-LA against E. coli was processed by the inhibition zone and growth curves. The modification of LA raised the antibacterial activity of CS-LA. The cytotoxicity assay of CS-LA-MTX to prostate cancer cells (RM-1) was examined. The load of MTX within CS-LA-MTX greatly enhanced the cytotoxicity to RM-1 cells. In summary, CS-LA hydrogel may provide a new copolymer carrier for drug package in food and biomedical application.

5.
Nat Commun ; 10(1): 5013, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676774

RESUMO

For atomically thin two-dimensional materials, interfacial effects may dominate the entire response of devices, because most of the atoms are in the interface/surface. Graphene/sapphire has great application in electronic devices and semiconductor thin-film growth, but the nature of this interface is largely unknown. Here we find that the sapphire surface has a strong interaction with some of the carbon atoms in graphene to form a C-O-Al configuration, indicating that the interface interaction is no longer a simple van der Waals interaction. In addition, the structural relaxation of sapphire near the interface is significantly suppressed and very different from that of a bare sapphire surface. Such an interfacial C-O-Al bond is formed during graphene growth at high temperature. Our study provides valuable insights into understanding the electronic structures of graphene on sapphire and remote control of epitaxy growth of thin films by using a graphene-sapphire substrate.

6.
Nucleic Acids Res ; 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31733060

RESUMO

As the largest group of MYB family transcription factors, R2R3-MYB proteins play essential roles during plant growth and development. However, the structural basis underlying how R2R3-MYBs recognize the target DNA remains elusive. Here, we report the crystal structure of Arabidopsis WEREWOLF (WER), an R2R3-MYB protein, in complex with its target DNA. Structural analysis showed that the third α-helices in both the R2 and R3 repeats of WER fit in the major groove of the DNA, specifically recognizing the DNA motif 5'-AACNGC-3'. In combination with mutagenesis, in vitro binding and in vivo luciferase assays, we showed that K55, N106, K109 and N110 are critical for the function of WER. Although L59 of WER is not involved in DNA binding in the structure, ITC analysis suggested that L59 plays an important role in sensing DNA methylation at the fifth position of cytosine (5mC). Like 5mC, methylation at the sixth position of adenine (6mA) in the AAC element also inhibits the interaction between WER and its target DNA. Our study not only unravels the molecular basis of how WER recognizes its target DNA, but also suggests that 5mC and 6mA modifications may block the interaction between R2R3-MYB transcription factors and their target genes.

7.
Small ; 15(47): e1904372, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31609079

RESUMO

Minimization of defects and ion migration in organic-inorganic lead halide perovskite films is desirable for obtaining photovoltaic devices with high power conversion efficiency (PCE) and long-term stability. However, achieving this target is still a challenge due to the lack of efficient multifunctional passivators. Herein, to address this issue, n-type goethite (FeOOH) quantum dots (QDs) are introduced into the perovskite light-absorption layer for achieving efficient and stable perovskite solar cells (PSCs). It is found that the iron, oxygen, and hydroxyl of FeOOH QDs can interact with iodine, lead, and methylamine, respectively. As a result, the crystallization kinetics process can be retarded, thereby resulting in high quality perovskite films with large grain size. Meanwhile, the trap states of perovskite can be effectively passivated via interaction with the under-coordinated metal (Pb) cations, halide (I) anions on the perovskite crystal surface. Consequently, the PSCs with FeOOH QDs achieve a high efficiency close to 20% with negligible hysteresis. Most strikingly, the long-term stability of PSCs is significantly enhanced. Furthermore, compared with the CH3 NH3 PbI3 -based device, a higher PCE of 21.0% is achieved for the device assembled with a Cs0.05 FA0.81 MA0.14 PbBr0.45 I2.55 perovskite layer.

8.
ACS Nano ; 13(11): 12912-12928, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31651142

RESUMO

Tumor microenvironment responsive multimodal synergistic theranostic strategies can significantly improve the therapeutic efficacy while avoiding severe side effects. Inspired by the fact that special morphology could enhance photothermal conversion efficiency (PCE) and cellular delivery, we developed an acidic tumor microenvironment responsive shape-reversal metal-organic virus-inspired nanodrug for enhancing near-infrared (NIR)-II PCE, increasing cell adhesion, and activating tumor targeting. First, a NIR-I fluorescence probe (IR825), a chemo-drug (pemetrexed, PEM), and a rare-earth metal ion (Nd(III)) were chosen to synthesize a virus-like nanodrug via coordination-driven assembly. Then, the spike-like surface of the nanodrug was further camouflaged by an acidity-sensitive poly(ethylene glycol) "shell" to create virus-core and sphere-shell hierarchical nanoassemblies, which could efficiently prevent immune clearance and prolong systemic circulation. Interestingly, the acidic tumor microenvironment could trigger the shell detachment of nanoassemblies for shape reversal to produce a virus-like surface followed by re-exposure of PEM to synergistically amplify the cellular internalization while enhancing NIR-II PCE. By utilizing the shell-detached virus-like nanodrug core, the tumor microenvironment specific enhanced NIR-II photothermal chemotherapy can be realized under the precise guidance of fluorescence/photoacoustic imaging, thereby achieving complete tumor elimination without recurrence in a single treatment cycle. We envision that integrating the tumor microenvironment responsive ability with  "sphere-to-virus" shape reversal will provide a promising strategy for biomimetic targeted cancer therapy.

9.
Basic Res Cardiol ; 114(6): 41, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31502080

RESUMO

Carotid baroreceptor stimulation (CBS) has been shown to improve cardiac dysfunction and pathological structure remodelling. This study aimed to investigate the effects of CBS on the ventricular electrophysiological properties in canines with chronic heart failure (CHF). Thirty-eight beagles were randomized into control (CON), CHF, low-level CBS (LL-CBS), and moderate-level CBS (ML-CBS) groups. The CHF model was established with 6 weeks of rapid right ventricular pacing (RVP), and concomitant LL-CBS and ML-CBS were applied in the LL-CBS and ML-CBS groups, respectively. After 6 weeks of RVP, ventricular electrophysiological parameters and left stellate ganglion (LSG) neural activity and function were measured. Autonomic neural remodelling in the LSG and left ventricle (LV) and ionic remodelling in the LV were detected. Compared with the CHF group, both LL-CBS and ML-CBS decreased spatial dispersion of action potential duration (APD), suppressed APD alternans, reduced ventricular fibrillation (VF) inducibility, and inhibited enhanced LSG neural discharge and function. Only ML-CBS significantly inhibited ventricular repolarization prolongation and increased the VF threshold. Moreover, ML-CBS inhibited the increase in growth-associated protein-43 and tyrosine hydroxylase-positive nerve fibre densities in LV, increased acetylcholinesterase protein expression in LSG, and decreased nerve growth factor protein expression in LSG and LV. Chronic RVP resulted in a remarkable reduction in protein expression encoding both potassium and L-type calcium currents; these changes were partly amended by ML-CBS and LL-CBS. In conclusion, CBS suppresses VF in CHF canines, potentially by modulating autonomic nerve and ion channels. In addition, the effects of ML-CBS on ventricular electrophysiological properties, autonomic remodelling, and ionic remodelling were superior to those of LL-CBS.

10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(4): 450-452, 2019 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-31512843

RESUMO

Negative pressure pulmonary edema is a rare complication of general anesthesia. This paper presents a case of acute negative pressure pulmonary edema that occurred during general anesthesia resuscitation. The patient is a young male that underwent bimaxillary surgery under general anesthesia. Laryngospasm spasm ensued after extubation. The treatment for laryngeal spasm retained the smoothness of the nasopharyngal airway, and the pulse oxygen saturation rapidly decreased after anesthesia resuscitation. Pink foam sputum was sucked out from the cavity due to respiratory shortness from mouth and nose. Highly concentrated oxygen was immediately given to assist ventilation and as a symptomatic support (diuretics, hormones), and the condition evidently improved. The diagnosis and treatment of this case suggest that when acute pulmonary edema occurs during general anesthesia resuscitation, negative pressure pulmonary edema should be highly suspected. The first line of treatment is to relieve respiratory tract obstruction. Supplying highly concentrated oxygen to assist positive pressure ventilation is an effective treatment to alleviate pulmonary edema.


Assuntos
Obstrução das Vias Respiratórias , Laringismo , Edema Pulmonar , Anestesia Geral , Humanos , Masculino , Resultado do Tratamento
11.
Ann Transl Med ; 7(16): 377, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31555691

RESUMO

Background: The prognostic role of squamous differentiation in upper urinary tract urothelial carcinoma (UTUC) is still unclear. This article describes the impact of squamous differentiation on prognosis and intravesical recurrence of patients with primary UTUC treated with radical nephroureterectomy (RNU). Methods: Totally, we retrieved (I) 669 histologically confirmed UTUC patients without histologic variants; (II) 101 UTUC patients with squamous differentiation in our institution, dating from April 2003 to April 2016. The clinical pathological characteristics and survival outcomes were compared between these two cohorts. Results: In our study, 13% UTUC patients were detected with squamous differentiation. The mean age of all the patients examined was 66, of whom 70% were males. Squamous differentiation significantly associated with tumor stage, tumor grade and lymphovascular invasion. The Kaplan-Meier and Cox regression analyses showed that presence of squamous differentiation was correlated with shorter cancer specific survival of UTUC patients. The 5-year cancer specific survival rates were 47% for squamous differentiation-present patients and 63% for squamous differentiation-absent patients. UTUC patients with squamous differentiation showed a higher frequency of high-grade disease in advanced stage (pT2/pT3/pT4), while the discrepancy was not shown in early stage (pTa/pT1). Intravesical recurrence was observed in 27% patients. We found that intravesical recurrence had little impact on the cancer specific survival of squamous differentiation-present patients, yet it tended to decrease cancer specific survival among squamous differentiation-absent patients. Conclusions: The presence of squamous differentiation in UTUC patients was a vital prognostic factor for cancer specific survival and correlated with intravesical recurrence after receiving RNU.

12.
Int J Biol Macromol ; 139: 521-530, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377297

RESUMO

Chitosan-1-(mercaptomethyl)-cyclopropane acetic acid (CS-MCA) copolymer was synthesized by amino linkage. The obtained copolymer was characterized by FTIR, 1H NMR, XRD, TGA and SEM. Porous and reticulate morphologies were found on the CS-MCA surface. The effects of pH on the rheological properties of CS-MCA were investigated. On the one hand, the apparent viscosity of CS-MCA indicated a shear-thinning behavior. The graft of MCA enhanced the moduli and the maximum elastic properties were observed at pH = 7.00. The addition of dithiothreitol reduced the viscosity and modulus of CS-MCA hydrogel, and the gelation time, temperature and frequency were obtained in dynamic oscillatory tests. The antibacterial effect of CS-MCA against E. coli was investigated for the inhibition zone and bacterial growth curve. These results showed that CS-MCA had better antibacterial ability than chitosan without modification. Therefore, the rheological behavior and functional activities can be applied for the hydrocolloid gels in food and pharmaceutical applications.

13.
Zookeys ; 861: 53-61, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333324

RESUMO

A new species of the bamboo-feeding leafhopper genus Bambusana Anufriev, 1969, B.longispina Luo & Chen, sp. nov. is described and illustrated from China (Yunnan Province). A checklist and key to known species of this genus are provided. Figures are also provided for B.bambusae, B.biflaka, B.fopingensis and B.multidentata.

14.
Clin Neurol Neurosurg ; 184: 105421, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31319236

RESUMO

McLeod syndrome (MLS) is a rare multisystem disorder and X-linked recessive inheritance disorder caused by mutations of the X-linked Kx blood group (XK) gene. The manifestations progress slowly and mainly appear in middle age, which make it difficult to distinguish MLS from other neuromuscular disorders. Here, we present a case of a 10-month-old Chinese boy who was taken to hospital for herpes of the extremities and oral cavity along with febrile seizures in June 2017. The laboratory test revealed persistent elevated levels of serum creatine phosphokinase and abnormal liver function. The results of the electrocardiogram showed sinus tachycardia, and magnetic resonance imaging of the brain showed enlarged bilateral ventricles and third ventricle. Genetic analysis by next-generation sequencing revealed a novel nonsense mutation c.89C > A (p. Ser30X) in exon 1 of XK. To the best of our knowledge, this is the first case report of infants with MLS confirmed by genetic analysis.

15.
Nat Hum Behav ; 3(9): 950-961, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31358974

RESUMO

Excessive alcohol consumption is one of the main causes of death and disability worldwide. Alcohol consumption is a heritable complex trait. Here we conducted a meta-analysis of genome-wide association studies of alcohol consumption (g d-1) from the UK Biobank, the Alcohol Genome-Wide Consortium and the Cohorts for Heart and Aging Research in Genomic Epidemiology Plus consortia, collecting data from 480,842 people of European descent to decipher the genetic architecture of alcohol intake. We identified 46 new common loci and investigated their potential functional importance using magnetic resonance imaging data and gene expression studies. We identify genetic pathways associated with alcohol consumption and suggest genetic mechanisms that are shared with neuropsychiatric disorders such as schizophrenia.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31326579

RESUMO

OBJECTIVE: Cannabis consumption during adolescence has been reported as a risk factor for psychotic-like experiences (PLEs) and schizophrenia. However, brain developmental processes associated with cannabis-related PLEs are still poorly described. METHOD: A total of 706 adolescents from the general population who were recruited by the IMAGEN consortium had structural magnetic resonance imaging scans at both 14 and 19 years of age. We used deformation-based morphometry to map voxelwise brain changes between the two time points, using the pairwise algorithm in SPM12b. We used an a priori region-of-interest approach focusing on the hippocampus/parahippocampus to perform voxelwise linear regressions. Lifetime cannabis consumption was assessed using the European School Survey Project on Alcohol and other Drugs (ESPAD), and PLEs were assessed with the Comprehensive Assessment Psychotic-like experiences (CAPE) tool. We first tested whether hippocampus/parahippocampus development was associated with PLEs. Then we formulated and tested an a priori simple mediation model in which uncus development mediates the association between lifetime cannabis consumption and PLEs. RESULTS: We found that PLEs were associated with reduced expansion within a specific region of the right hippocampus/parahippocampus formation, the uncus (p = .002 at the cluster level, p = .018 at the peak level). The partial simple mediation model revealed a significant total effect from lifetime cannabis consumption to PLEs (b = 0.069, 95% CI = 0.04-0.1, p =2 × 10-16), as well as a small yet significant, indirect effect of right uncus development (0.004; 95% CI = 0.0004-0.01, p = .026). CONCLUSION: We show here that the uncus development is involved in the cerebral basis of PLEs in a population-based sample of healthy adolescents.

17.
Nanoscale ; 11(27): 12973-12982, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31263818

RESUMO

Nano-theranostic agents play important roles in the development of therapeutic methods for serious diseases. In this study, novel carbon dots (CDs) L-CD/C-CD were prepared from Gd(iii) salt/complexes, cationic polymers and citric acid in the hope that they would combine the abilities of gene delivery and multi-modal (MR/FL) imaging. The CDs inherited the properties of good water-solubility and positive charge from their precursor polymers. In vitro gene transfection results showed that the CDs have good transfection efficiency and anti-serum ability, especially for L-CD, which has 74 times higher transfection efficiency than PEI 25 kDa in the presence of 10% serum. The CDs exhibited bright fluorescence, which was stable for several days under various pH. Confocal laser scanning microscopy revealed that the CDs could image HeLa cells with blue or green fluorescence well, and realize the monitoring of the gene delivery process. Besides, the CDs showed favorable biocompatibility with excellent performance in longitudinal relaxivity rates (r1) of 11.4 mM-1 s-1 for L-CD and 57.6 mM-1 s-1 for C-CD, which were about 3-15 times higher than that of the clinical Gd reagent Gd-DTPA (3.75 mM-1 s-1). Furthermore, the CDs could perform in vivo tumor-specific MR-imaging more clearly than Gd-DTPA, which is attributed to their suitable particle size and their resulting greater accumulation at tumor site via the EPR effect. This study provides a promising strategy for constructing multi-functional CDs for tumor theranostics.

18.
Int Immunopharmacol ; 74: 105737, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31288152

RESUMO

Influenza A virus usually leads to economic loss to breeding farms and pose a serious threat to human health. Virus infecting tissues directly and influenza virus-induced excessive production of inflammatory factors play the key role in pathogenesis of the disease, but the mechanism is not well clarified. Here, the role of autophagy was investigated in H9N2 influenza virus-triggered inflammation. The results showed that autophagy was induced by H9N2 virus in A549 cells and in mice. Inhibiting autophagy by an autophagy inhibitor (3-methyladenine, 3-MA) or knockdown of Atg5(autophagy-related gene) by Atg5 siRNA significantly suppressed H9N2 virus replication, H9N2 virus-triggered inflammatory cytokines and chemokines, including IL-1ß, TNF-α, IL-8, and CCL5 in vitro and in vivo, and suppressed H9N2 virus-triggered acute lung injury as indicated as accumulative mortality of mice, inflammatory cellular infiltrate and interstitial edema, thickening of the alveolar walls in mice lung tissues, increased inflammatory cytokines and chemokines, increased W/D ratio in mice. Moreover, autophagy mediated inflammatory responses through Akt-mTOR, NF-κB and MAPKs signaling pathways. Our data showed that autophagy was essential in H9N2 influenza virus-triggered inflammatory responses, and autophagy could be target to treat influenza virus-caused lung inflammation.

19.
Chem Commun (Camb) ; 55(61): 9011-9014, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31290869

RESUMO

For effective hydrogen generation with remarkable durability, carbon nanotubes (CNTs) grown on Ni nanofibers and their post hydroxylation treatment engendered active Ni nanofiber catalysts an efficient decomposition of hydrous hydrazine with a turnover frequency (TOF) of 19.4 h-1 and an activation energy down to 51.05 KJ mol-1.

20.
Nat Commun ; 10(1): 2999, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31278262

RESUMO

The different genome-wide distributions of tri-methylation at H3K36 (H3K36me3) in various species suggest diverse mechanisms for H3K36me3 establishment during evolution. Here, we show that the transcription factor OsSUF4 recognizes a specific 7-bp DNA element, broadly distributes throughout the rice genome, and recruits the H3K36 methyltransferase SDG725 to target a set of genes including the key florigen genes RFT1 and Hd3a to promote flowering in rice. Biochemical and structural analyses indicate that several positive residues within the zinc finger domain are vital for OsSUF4 function in planta. Our results reveal a regulatory mechanism contributing to H3K36me3 distribution in plants.


Assuntos
Histona-Lisina N-Metiltransferase/metabolismo , Histonas/genética , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Transativadores/metabolismo , Metilação de DNA/fisiologia , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/fisiologia , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética
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