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1.
Small ; 19(34): e2301516, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37086123

RESUMO

Proton exchange membrane water electrolyzer (PEMWE) is a green hydrogen production technology that can be coupled with intermittent power sources such as wind and photoelectric power. To achieve cost-effective operations, low noble metal loading on the anode catalyst layer is desired. In this study, a catalyst with RuO2 nanorods coated outside SnO2 nanocubes is designed, which forms continuous networks and provides high conductivity. This allows for the reduction of Ru contents in catalysts. Furthermore, the structure evolutions on the RuO2 surface are carefully investigated. The etched RuO2 surfaces are seen as the consequence of Co leaching, and theoretical calculations demonstrate that it is more effective in driving oxygen evolution. For electrochemical tests, the catalysts with 23 wt% Ru exhibit an overpotential of 178 mV at 10 mA cm-2 , which is much higher than most state-of-art oxygen evolution catalysts. In a practical PEMWE, the noble metal Ru loading on the anode side is only 0.3 mg cm-2 . The cell achieves 1.61 V at 1 A cm-2 and proper stability at 500 mA cm-2 , demonstrating the effectiveness of the designed catalyst.

2.
Nanotechnology ; 34(48)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37625396

RESUMO

Extensive investigations have been devoted to nitrogen-doped carbon materials as catalysts for the oxygen reduction reaction (ORR) in various conversion technologies. In this study, we introduce nitrogen-doped carbon materials with hollow spherical structures. These materials demonstrate significant potential in ORR activity within alkaline media, showing a half-wave potential of 0.87 V versus the reversible hydrogen electrode (RHE). Nitrogen-doped hollow carbon spheres (N-CHS) exhibit unique characteristics such as a thin carbon shell layer, hollow structure, large surface area, and distinct pore features. These features collectively create an optimal environment for facilitating the diffusion of reactants, thereby enhancing the exposure of active sites and improving catalytic performance. Building upon the promising qualities of N-CHS as a catalyst support, we employ heme chloride (1 wt%) as the source of iron for Fe doping. Through the carbonization process, Fe-N active sites are effectively formed, displaying a half-wave potential of 0.9 V versus RHE. Notably, when implemented as a cathode catalyst in zinc-air batteries, this catalyst exhibits an impressive power density of 162.6 mW cm-2.

3.
Cell Mol Biol (Noisy-le-grand) ; 68(5): 103-110, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36029492

RESUMO

The study focused on the role of mitophagy in neonatal ventilator-induced lung injury (VILI). Immunoassays were used to study the TLR9 signaling pathway of neonatal VILI, expected to provide a feasible solution for neonatal VILI. The mice were randomly divided into four groups, group A: spontaneous breathing group; group B: normal tidal volume (VT) group (VT=9mL/kg); group C: high VT group (VT=39mL/kg); and group D: ODN2088 (400µg/ Only) intervention + high VT group. The four groups were compared for the expression of inflammatory factors. It was found that as the culture time increased, the expression of TLR9, MyD88, and NF-κBp65 in the lung tissue of the large VT group was significantly higher than those in the spontaneous breathing group and normal VT group, and the differences were statistically significant; and TLR9 inhibitors could activate the TLR9-MyD88 signaling pathway to up-regulate the expression of NF-κB, mediating the release of inflammatory factors to cause VILI.


Assuntos
Receptor Toll-Like 9 , Lesão Pulmonar Induzida por Ventilação Mecânica , Animais , Camundongos , Mitofagia , Fator 88 de Diferenciação Mieloide , Transdução de Sinais
4.
Int J Mol Sci ; 23(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35163836

RESUMO

Female sterility is a common phenomenon in the plant world, and systematic research has not been carried out in gymnosperms. In this study, the ovules of No. 28 sterile line and No. 15 fertile line Pinus tabuliformis were used as materials, and a total of 18 cDNA libraries were sequenced by the HiSeqTM 4000 platform to analyze the differentially expressed genes (DEGs) and simple sequence repeats (SSRs) between the two lines. In addition, this study further analyzed the DEGs involved in the signal transduction of plant hormones, revealing that the signal pathways related to auxin, cytokinin, and gibberellin were blocked in the sterile ovule. Additionally, real-time fluorescent quantitative PCR verified that the expression trend of DEGs related to plant hormones was consistent with the results of high-throughput sequencing. Frozen sections and fluorescence in situ hybridization (FISH) were used to study the temporal and spatial expression patterns of PtRab in the ovules of P. tabuliformis. It was found that PtRab was significantly expressed in female gametophytes and rarely expressed in the surrounding diploid tissues. This study further explained the molecular regulation mechanism of female sterility in P. tabuliformis, preliminarily mining the key factors of ovule abortion in gymnosperms at the transcriptional level.


Assuntos
Perfilação da Expressão Gênica/métodos , Óvulo Vegetal/fisiologia , Pinus/fisiologia , Infertilidade das Plantas , Proteínas de Plantas/genética , Núcleo Celular/genética , Núcleo Celular/fisiologia , Análise por Conglomerados , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Hibridização in Situ Fluorescente , Mitose , Óvulo Vegetal/genética , Fenótipo , Pinus/genética , Especificidade da Espécie , Proteínas rab de Ligação ao GTP/genética
5.
Int J Mol Sci ; 22(6)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808669

RESUMO

Ovule abortion is a common phenomenon in plants that has an impact on seed production. Previous studies of ovule and female gametophyte (FG) development have mainly focused on angiosperms, especially in Arabidopsis thaliana. However, because it is difficult to acquire information about ovule development in gymnosperms, this remains unclear. Here, we investigated the transcriptomic data of natural ovule abortion mutants (female sterile line, STE) and the wild type (female fertile line, FER) of Pinus tabuliformis Carr. to evaluate the mechanism of ovule abortion during the process of free nuclear mitosis (FNM). Using single-molecule real-time (SMRT) sequencing and next-generation sequencing (NGS), 18 cDNA libraries via Illumina and two normalized libraries via PacBio, with a total of almost 400,000 reads, were obtained. Our analysis showed that the numbers of isoforms and alternative splicing (AS) patterns were significantly variable between FER and STE. The functional annotation results demonstrate that genes involved in the auxin response, energy metabolism, signal transduction, cell division, and stress response were differentially expressed in different lines. In particular, AUX/IAA, ARF2, SUS, and CYCB had significantly lower expression in STE, showing that auxin might be insufficient in STE, thus hindering nuclear division and influencing metabolism. Apoptosis in STE might also have affected the expression levels of these genes. To confirm the transcriptomic analysis results, nine pairs were confirmed by quantitative real-time PCR. Taken together, these results provide new insights into ovule abortion in gymnosperms and further reveal the regulatory mechanisms of ovule development.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Óvulo Vegetal/genética , Pinus/genética , Infertilidade das Plantas/genética , Transcriptoma , Biologia Computacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Imuno-Histoquímica , Repetições de Microssatélites , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
BMC Genomics ; 21(1): 852, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261554

RESUMO

BACKGROUND: The root growth angle (RGA) typically determines plant rooting depth, which is significant for plant anchorage and abiotic stress tolerance. Several quantitative trait loci (QTLs) for RGA have been identified in crops. However, the underlying mechanisms of the RGA remain poorly understood, especially in apple rootstocks. The objective of this study was to identify QTLs, validate genetic variation networks, and develop molecular markers for the RGA in apple rootstock. RESULTS: Bulked segregant analysis by sequencing (BSA-seq) identified 25 QTLs for RGA using 1955 hybrids of the apple rootstock cultivars 'Baleng Crab' (Malus robusta Rehd., large RGA) and 'M9' (M. pumila Mill., small RGA). With RNA sequencing (RNA-seq) and parental resequencing, six major functional genes were identified and constituted two genetic variation networks for the RGA. Two single nucleotide polymorphisms (SNPs) of the MdLAZY1 promoter damaged the binding sites of MdDREB2A and MdHSFB3, while one SNP of MdDREB2A and MdIAA1 affected the interactions of MdDREB2A/MdHSFB3 and MdIAA1/MdLAZY1, respectively. A SNP within the MdNPR5 promoter damaged the interaction between MdNPR5 and MdLBD41, while one SNP of MdLBD41 interrupted the MdLBD41/MdbHLH48 interaction that affected the binding ability of MdLBD41 on the MdNPR5 promoter. Twenty six SNP markers were designed on candidate genes in each QTL interval, and the marker effects varied from 0.22°-26.11°. CONCLUSIONS: Six diagnostic markers, SNP592, G122, b13, Z312, S1272, and S1288, were used to identify two intricate genetic variation networks that control the RGA and may provide new insights into the accuracy of the molecular markers. The QTLs and SNP markers can potentially be used to select deep-rooted apple rootstocks.


Assuntos
Malus , Marcadores Genéticos , Malus/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
7.
BMC Plant Biol ; 20(1): 149, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32268887

RESUMO

BACKGROUND: Podosphaera aphanis, a predominately biotrophic fungal pathogen, causes significant yield losses of strawberry. China is the largest strawberry producer in the world, and selecting for powdery mildew-resistant cultivars is desirable. However, the resistance mechanism against P. aphanis in the octoploid strawberry remains unclear. RESULTS: To understand possible mechanisms of disease resistance, we inoculated strawberry leaves with P. aphanis, and examined the expression profiles of candidate genes and the biochemical phenotypes in strawberry leaves of two groups. The unigenes obtained from ddH2O- and SA-pretreated leaves resulted in a total of 48,020 and 45,896 genes, respectively. KEGG enrichment showed that phenylpropanoid biosynthesis and plant hormone signal transduction pathways were enriched to a noticeable extent. DEG analysis showed that key TFs genes associated with the SA signaling pathway could play important role in the strawberry-P. aphanis interaction. In particular, FaWRKY70, FaJAZ1 and FaMYC2-like, involved in regulating the antagonistic effect of SA and JA signaling pathway, leading to increased expression of SA-responsive genes (in particular PR1, PR2, PR3, and PR5) compared to a decline in expression of JA-responsive genes (FaJAR1, FaAOS, and FaLOX2). Furthermore, SA pretreatment induced accumulation of PAs by activating the MBW complex and inhibit powdery mildew growth. CONCLUSIONS: This study describes the role of the proanthocyanidins (PAs), pathogenesis-related (PR) genes, SA, and transcription factors in regulatory model against P. aphanis, which coincided with an early activation of defense, leading to the accumulation of PAs and the PR proteins.


Assuntos
Ascomicetos/metabolismo , Resistência à Doença , Fragaria/microbiologia , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Proantocianidinas/metabolismo , Flavonoides/biossíntese , Fragaria/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Fatores de Transcrição/metabolismo , Transcriptoma
8.
Sensors (Basel) ; 20(11)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492842

RESUMO

Action recognition is a significant and challenging topic in the field of sensor and computer vision. Two-stream convolutional neural networks (CNNs) and 3D CNNs are two mainstream deep learning architectures for video action recognition. To combine them into one framework to further improve performance, we proposed a novel deep network, named the spatiotemporal interaction residual network with pseudo3D (STINP). The STINP possesses three advantages. First, the STINP consists of two branches constructed based on residual networks (ResNets) to simultaneously learn the spatial and temporal information of the video. Second, the STINP integrates the pseudo3D block into residual units for building the spatial branch, which ensures that the spatial branch can not only learn the appearance feature of the objects and scene in the video, but also capture the potential interaction information among the consecutive frames. Finally, the STINP adopts a simple but effective multiplication operation to fuse the spatial branch and temporal branch, which guarantees that the learned spatial and temporal representation can interact with each other during the entire process of training the STINP. Experiments were implemented on two classic action recognition datasets, UCF101 and HMDB51. The experimental results show that our proposed STINP can provide better performance for video recognition than other state-of-the-art algorithms.

9.
Entropy (Basel) ; 22(8)2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-33286670

RESUMO

Artificial intelligence is one of the most popular topics in computer science. Convolutional neural network (CNN), which is an important artificial intelligence deep learning model, has been widely used in many fields. However, training a CNN requires a large amount of labeled data to achieve a good performance but labeling data is a time-consuming and laborious work. Since active learning can effectively reduce the labeling effort, we propose a new intelligent active learning method for deep learning, which is called multi-view active learning based on double-branch network (MALDB). Different from most existing active learning methods, our proposed MALDB first integrates two Bayesian convolutional neural networks (BCNNs) with different structures as two branches of a classifier to learn the effective features for each sample. Then, MALDB performs data analysis on unlabeled dataset and queries the useful unlabeled samples based on different characteristics of two branches to iteratively expand the training dataset and improve the performance of classifier. Finally, MALDB combines multiple level information from multiple hidden layers of BCNNs to further improve the stability of sample selection. The experiments are conducted on five extensively used datasets, Fashion-MNIST, Cifar-10, SVHN, Scene-15 and UIUC-Sports, the experimental results demonstrate the validity of our proposed MALDB.

10.
J Cell Biochem ; 120(10): 17059-17066, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31111552

RESUMO

C1qTNF-related proteins (CTRPs) are a member of the adiponectin paralogs family, which are implicated in regulation of various biological processes. Recently, CTRP6 was found upregulated in human hepatocellular carcinomas (HCC). However, the specific roles and molecular mechanisms of CTRP6 in HCC remain unclear. Here, we investigated the effects of CTRP6 on the vitality, apoptosis, migration, and invasion of HCC cells. Firstly, we measured the levels of CTRP6 in HCC tissues and cell lines. Our results showed that CTRP6 was markedly upregulated in HCC tissues and Hep3B cells. Then, the CTRP6 siRNA was transfected into Hep3B cells. Cell counting kit-8 (CCK-8) assay and flow cytometry analysis revealed that silencing CTRP6-induced cell viability inhibition, and apoptosis. The wound-healing and transwell assay showed that CTRP6 deficiency suppressed the migration and invasion of Hep3B cells. Meanwhile, the AKT phosphorylation level was reduced by CTRP6 silencing. Next, Hep3B cells were pretreated with insulin-like growth factor-1 (IGF-1) (an activator of AKT), and then transfected with CTRP6 siRNA, and the cell vitality, apoptosis, migration, and invasion were measured again. We found that all these alterations caused by CTRP6 inhibition could be reversed by IGF-1 treatment. Taken together, CTRP6 suppression blocked cell survival, migration, and invasion and promoted cell apoptosis through inactivating the AKT signaling pathway. Our findings present a novel potential molecular target for HCC therapy.


Assuntos
Carcinoma Hepatocelular/genética , Caspase 3/genética , Colágeno/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Proteínas Proto-Oncogênicas c-akt/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Caspase 3/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno/antagonistas & inibidores , Colágeno/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
11.
J Neural Transm (Vienna) ; 126(8): 1081-1094, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31292734

RESUMO

Various studies report discordant results regarding the efficacy, parameters, and underlying mechanisms of repetitive transcranial magnetic stimulation (rTMS) combined with cognitive training (CT) on Alzheimer's disease (AD). The objective of the study was to assess the effect of rTMS-CT on cognition, the activities of daily life, neuropsychiatric behavioral symptoms, and metabolite levels beneath the stimulated areas of the brain in patients with AD and to investigate the correlation of metabolic changes (measured with proton magnetic resonance spectroscopy [1H-MRS]) with clinical outcomes after treatment. Thirty consecutive patients with mild or moderate AD were enrolled and randomly divided into one of the two intervention groups: (1) real rTMS with CT (i.e., real group) and (2) sham rTMS with CT (i.e., sham group). 10 Hz rTMS was used to stimulate the left dorsolateral prefrontal cortex (DLPFC) and then to stimulate the left lateral temporal lobe (LTL) for 20 min each day for 4 weeks. Each patient underwent neuropsychological assessment at baseline (T0), immediately after treatment (T1), and 4 weeks after treatment (T2). The ratios of N-acetylaspartate/creatine (NAA/Cr), myoinositol/creatine (mI/Cr), and choline/creatine (Cho/Cr) in the stimulated cortex were measured using 1H-MRS at T0 and T1. Twenty-eight patients were treated with rTMS-CT for 4 weeks. Two patients in the sham group withdrew after being treated several times. Compared with the sham group, the cognitive function and behavior in the real rTMS group improved significantly at T1 and T2. In the real group, compared with the sham group, the NAA/Cr ratio in the left DLPFC was significantly elevated (p = 0.045); however, in the left LTL, it only showed a tendency toward increase (p = 0.162). The change in the NAA/Cr ratio in the left DLPFC was negatively correlated with the change in the cognitive scales of the Alzheimer's Disease Assessment Scale (ADAS-cog). This study indicated a possible modest effect of rTMS-CT on preventing clinical and neuronal functional deterioration in the left DLPFC of patients with AD. The left DLPFC is a better candidate area than the left LTL.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Córtex Cerebral/metabolismo , Cognição , Estimulação Magnética Transcraniana , Atividades Cotidianas , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Córtex Cerebral/diagnóstico por imagem , Cognição/fisiologia , Terapia Combinada/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Dados Preliminares , Espectroscopia de Prótons por Ressonância Magnética , Agitação Psicomotora/metabolismo , Agitação Psicomotora/terapia , Índice de Gravidade de Doença , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
12.
Med Sci Monit ; 25: 10077-10088, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31883264

RESUMO

BACKGROUND In China, electroacupuncture (EA) is used to treat the symptoms of ischemic stroke. However, the mechanisms involved in the effects of EA in cerebral ischemia remain to be investigated. This study aimed to investigate the molecular mechanism underlying the effects of EA in a rat model of cerebral ischemia-reperfusion injury (CIRI) induced by middle cerebral artery occlusion (MCAO). MATERIAL AND METHODS Seventy-five male Sprague-Dawley rats were divided into five groups: the sham group (with sham surgery), the model group (the MCAO model), the EA group (treated with EA), the EA control group, and the EA+antagomir-223-3p group. Rats in the model of CIRI underwent MCAO for 90 minutes. EA was performed on the second postoperative day and was performed at the Waiguan (TE5) and Zusanli (ST36) acupoints. The rat brains were evaluated for structural and molecular markers. RESULTS EA treatment significantly upregulated the expression of microRNA-223 (miR-223), NESTIN, and NOTCH1, and downregulated the expression of PTEN in the subventricular zone (SVZ) and hippocampus. The luciferase reporter assay supported that PTEN was a direct target of miR-223, and antagomiR-223-3p reversed the effects of EA and reduced the increase in NESTIN and inhibition of PTEN expression associated with EA treatment. There was a negative correlation between PTEN expression and the number of neural stem cells (NSCs). CONCLUSIONS In a rat model of CIRI following MCAO, EA activated the NOTCH pathway, promoted the expression of miR-223, increased the number of NSCs, and reduced the expression of PTEN.


Assuntos
Isquemia Encefálica/etiologia , Isquemia Encefálica/terapia , Eletroacupuntura , Infarto da Artéria Cerebral Média/complicações , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/terapia , Animais , Antagomirs/farmacologia , Sequência de Bases , Isquemia Encefálica/genética , Hipocampo/patologia , Masculino , MicroRNAs/genética , Nestina/metabolismo , Neuroproteção , Ratos Sprague-Dawley , Receptores Notch/genética , Receptores Notch/metabolismo , Traumatismo por Reperfusão/genética , Transdução de Sinais , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
13.
Med Sci Monit ; 25: 4723-4733, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31237865

RESUMO

BACKGROUND Electroacupuncture (EA) has been commonly used to treat stroke in China. However, the underlying mechanism remains largely unknown. The present study investigated the neuroprotective effects of EA in middle cerebral artery occlusion (MCAO) rats and elucidated the possible anti-inflammatory mechanisms. MATERIAL AND METHODS In this study, modified neurological severity scoring (mNSS) was used to assess neurological deficits, and TTC staining and brain water content were measured to evaluate the degree of brain damage. HE staining, Nissl staining, and TUNEL staining were employed to evaluate apoptotic neuronal death. Molecular biological methods were used to measure the levels of miR-233, NLRP3, caspase-1, IL-1ß, and IL-18 in the peri-infarct cortex. RESULTS Our results showed that EA treatment significantly decreased the neurological deficit score and infarct volume of MCAO rats. The level of miR-223 was increased, while the levels of NLRP3, caspase-1, IL-1ß, and IL-18 were decreased in the peri-infarct cortex of EA-treated MCAO rats. However, the neuroprotective effect of EA was partially blocked by antagomir-223. CONCLUSIONS These data suggest that EA treatment can alleviate neuroinflammation by inhibiting the miR-223/NLRP3 pathway, thus playing a neuroprotective role in MCAO in rats.


Assuntos
Isquemia Encefálica/terapia , Eletroacupuntura/métodos , Infarto da Artéria Cerebral Média/terapia , MicroRNAs/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Pontos de Acupuntura , Animais , Encéfalo/metabolismo , Lesões Encefálicas/metabolismo , Isquemia Encefálica/metabolismo , Córtex Cerebral/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/terapia
14.
Int J Mol Sci ; 20(20)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627402

RESUMO

Heterophylly is the phenomenon of leaf forms varying along the longitudinal axis within a single plant. Populus euphratica, a heterophyllous woody plant, develops lanceolate leaves and dentate broad-ovate leaves on the bottom and top of the canopy, respectively, which are faced with different intensities of ambient solar radiation. However, the mechanism of the heteromorphic leaf response to the microenvironment in P. euphratica remains elusive. Here, we show that the dentate broad-ovate leaves have advantages in tolerating high light intensity, while lanceolate leaves are excellent at capturing light. Compared with lanceolate leaves, more trichomes, higher stomatal density, thicker lamina, and higher specific leaf weight were observed in dentate broad-ovate leaves. Furthermore, high-throughput RNA sequencing analysis revealed that the expression patterns of genes and long noncoding RNAs (lncRNAs) are different between the two heteromorphic leaves. A total of 36,492 genes and 1725 lncRNAs were detected, among which 586 genes and 54 lncRNAs were differentially expressed. Based on targets prediction, lncRNAs and target genes involved in light adaption, protein repair, stress response, and growth and development pathways were differentially expressed in heteromorphic leaves, 10 pairs of which were confirmed by quantitative real-time PCR. Additionally, the analysis of interactions indicated that lncRNA-mRNA interactions were involved in the response to the microenvironment of heteromorphic leaves. Taken together, these results suggest that the morphological features and joint regulation of lncRNA-mRNA in heteromorphic leaves may serve as survival strategies for P. euphratica, which could lead to optimal utilization of environmental factors.


Assuntos
Folhas de Planta/anatomia & histologia , Populus/anatomia & histologia , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo , Adaptação Fisiológica , Microambiente Celular , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/efeitos da radiação , Populus/genética , Populus/crescimento & desenvolvimento , Populus/efeitos da radiação , Estresse Fisiológico , Luz Solar
15.
Int J Mol Sci ; 19(8)2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30071597

RESUMO

The development of the female gametophyte (FG) is one of the key processes of life cycle alteration between the haploid gametophyte and the diploid sporophytes in plants and it is required for successful seed development after fertilization. It is well demonstrated that free nuclear mitosis (FNM) of FG is crucial for the development of the ovule. However, studies of the molecular mechanism of ovule and FG development focused mainly on angiosperms, such as Arabidopsis thaliana and further investigation of gymnosperms remains to be completed. Here, Illumina sequencing of six transcriptomic libraries obtained from developing and abortive ovules at different stages during free nuclear mitosis of magagametophyte (FNMM) was used to acquire transcriptome data and gene expression profiles of Pinus tabulaeformis. Six cDNA libraries generated a total of 71.0 million high-quality clean reads that aligned with 63,449 unigenes and the comparison between developing and abortive ovules identified 7174 differentially expressed genes (DEGs). From the functional annotation results, DEGs involved in the cell cycle and phytohormone regulation were highlighted to reveal their biological importance in ovule development. Furthermore, validation of DEGs from the phytohormone signal transduction pathway was performed using quantitative real-time PCR analysis, revealing the dynamics of transcriptional networks and potential key components in the regulation of FG development in P. tabulaeformis were identified. These findings provide new insights into the regulatory mechanisms of ovule development in woody gymnosperms.


Assuntos
Regulação da Expressão Gênica de Plantas/fisiologia , Mitose/fisiologia , Óvulo Vegetal , RNA de Plantas , Análise de Sequência de RNA , Fertilidade , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Pinus , RNA de Plantas/biossíntese , RNA de Plantas/genética
16.
J Ultrasound Med ; 36(2): 261-268, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27914175

RESUMO

OBJECTIVES: We aimed to evaluate the validity of transient elastography in monitoring the antiviral outcomes in patients with chronic hepatitis B. METHODS: This study included 108 patients treated with nucleos(t)ide analogues and 67 patients treated with interferon (IFN). Liver biopsies were evaluated by the METAVIR score. Transient elastography was performed initially at baseline, 48 weeks, and 96 weeks. Liver tissue was obtained before and after 96 weeks of treatment. The area under the receiver operating characteristic curve was used to examine the diagnostic value of transient elastography in predicting and monitoring outcomes of antiviral treatment. RESULTS: The liver stiffness value correlated well with the baseline alanine aminotransferase level (r = 0.33; P < .001) and was significantly different among various stages of liver fibrosis (P < .001). In the nucleos(t)ide analogue group, the mean pretreatment and posttreatment liver stiffness values ± SD were 8.7 ± 3.1 and 5.9 ± 1.6 kPa, respectively (P < .001), and they were 9.2 ± 3.7 and 7.2 ± 1.9 kPa (P < .001) in the IFN group. Although the liver stiffness values at baseline between the groups were similar (P = .45), they were 5.9 ± 1.6 kPa in the nucleos(t)ide analogue group and 7.2 ± 1.9 kPa in the IFN group after 48 weeks of treatment (P < .001). With the decreased magnitude liver stiffness for predicting the improvement in liver fibrosis, the area under the receiver operating characteristic curve was 0.68 (P = .029). When the decreased magnitude of liver stiffness was 4.1 kPa or higher, the sensitivity and specificity for predicting a histologic response were 88.2% and 50.0%. CONCLUSIONS: Our findings suggest that transient elastography is an effective measurement tool for diagnosing and monitoring the histologic response in patients with chronic hepatitis B during antiviral treatment and can help avoid multiple liver biopsies.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatite B Crônica/diagnóstico por imagem , Hepatite B Crônica/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Adulto , Antivirais/uso terapêutico , Feminino , Seguimentos , Hepatite B Crônica/tratamento farmacológico , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Virol J ; 13: 64, 2016 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-27062520

RESUMO

BACKGROUND: To assess the potential effects of telbivudine (LdT) and entecavir (ETV) on renal function in patients with chronic hepatitis B (CHB), we performed a meta-analysis of the relevant data available on these agents to evaluate their effects on the estimated glomerular filtration rate (eGFR) during treatment. METHODS: The PubMed, EMBASE, Scopus, CNKI (China National Knowledge Infrastructure), Cochrane Library, and WanFang databases were searched for relevant articles appearing in the literature up to July 1, 2015. A total of 6 studies (1960 CHB patients) with 1-year eGFR outcomes were retrieved and analyzed. RESULTS: Generally, the results of the 6 studies analyzed showed that eGFR was improved after LdT treatment, but was decreased after ETV treatment. Using a fixed-effects approach, the change in eGFR was found to be significantly different between LdT and ETV treatment (Z = 3.64; P = 0.0003). Whereas the eGFR was slightly decreased with ETV compared with baseline (-1.45 mL/min/1.73 m(2)), the eGFR was improved with LdT (2.99 mL/min/1.73 m(2)) after 1 year of treatment. An overall test of effect in the meta-analysis showed that the eGFR in LdT-treated patients was significantly improved after 1-year of treatment (Z = 3.71; P = 0.0002). CONCLUSION: This meta-analysis has confirmed that LdT has a renal protective effect whereas ETV does not. However, whether the benefit on renal function outweighs the occurrence of resistance in specific clinical situations is not yet clear.


Assuntos
Antivirais/efeitos adversos , Guanina/análogos & derivados , Nefropatias/induzido quimicamente , Rim/efeitos dos fármacos , Rim/fisiologia , Timidina/análogos & derivados , Antivirais/uso terapêutico , China , Guanina/efeitos adversos , Guanina/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Humanos , Testes de Função Renal , Telbivudina , Timidina/efeitos adversos , Timidina/uso terapêutico
18.
Phys Chem Chem Phys ; 16(30): 15941-7, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24964174

RESUMO

Surfactant-free nanospheres and latex nanospheres of poly(methyl methacrylate) (PMMA) with diameter ranging from 20 to 220 nm are prepared by atom transfer radical polymerization (ATRP) in microemulsions and subsequent dialysis against deionized water. The glass transitions of these PMMA nanospheres are characterized using nano differential scanning calorimetry (nano-DSC) in aqueous dispersions. The glass transition temperature (Tg) of the surfactant-free PMMA nanospheres and nonionic PMMA latex nanospheres with diameters below 150 nm is less than that of the PMMA bulk, and Tg decreases with the decrease of the diameter. In contrast, Tg of the anionic PMMA latex nanospheres is size-independent and is near to that of the PMMA bulk. The influence of the environment surrounding the PMMA nanospheres on glass transitions as well as comparisons to our prior studies with polystyrene (PS) nanospheres in aqueous dispersions are discussed.

19.
Biomed Opt Express ; 15(6): 3975-3992, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38867792

RESUMO

Segmenting the optic disc (OD) and optic cup (OC) is crucial to accurately detect changes in glaucoma progression in the elderly. Recently, various convolutional neural networks have emerged to deal with OD and OC segmentation. Due to the domain shift problem, achieving high-accuracy segmentation of OD and OC from different domain datasets remains highly challenging. Unsupervised domain adaptation has taken extensive focus as a way to address this problem. In this work, we propose a novel unsupervised domain adaptation method, called entropy and distance-guided super self-ensembling (EDSS), to enhance the segmentation performance of OD and OC. EDSS is comprised of two self-ensembling models, and the Gaussian noise is added to the weights of the whole network. Firstly, we design a super self-ensembling (SSE) framework, which can combine two self-ensembling to learn more discriminative information about images. Secondly, we propose a novel exponential moving average with Gaussian noise (G-EMA) to enhance the robustness of the self-ensembling framework. Thirdly, we propose an effective multi-information fusion strategy (MFS) to guide and improve the domain adaptation process. We evaluate the proposed EDSS on two public fundus image datasets RIGA+ and REFUGE. Large amounts of experimental results demonstrate that the proposed EDSS outperforms state-of-the-art segmentation methods with unsupervised domain adaptation, e.g., the Dicemean score on three test sub-datasets of RIGA+ are 0.8442, 0.8772 and 0.9006, respectively, and the Dicemean score on the REFUGE dataset is 0.9154.

20.
Comput Biol Med ; 171: 108184, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417386

RESUMO

How to fuse low-level and high-level features effectively is crucial to improving the accuracy of medical image segmentation. Most CNN-based segmentation models on this topic usually adopt attention mechanisms to achieve the fusion of different level features, but they have not effectively utilized the guided information of high-level features, which is often highly beneficial to improve the performance of the segmentation model, to guide the extraction of low-level features. To address this problem, we design multiple guided modules and develop a boundary-guided filter network (BGF-Net) to obtain more accurate medical image segmentation. To the best of our knowledge, this is the first time that boundary guided information is introduced into the medical image segmentation task. Specifically, we first propose a simple yet effective channel boundary guided module to make the segmentation model pay more attention to the relevant channel weights. We further design a novel spatial boundary guided module to complement the channel boundary guided module and aware of the most important spatial positions. Finally, we propose a boundary guided filter to preserve the structural information from the previous feature map and guide the model to learn more important feature information. Moreover, we conduct extensive experiments on skin lesion, polyp, and gland segmentation datasets including ISIC 2016, CVC-EndoSceneStil and GlaS to test the proposed BGF-Net. The experimental results demonstrate that BGF-Net performs better than other state-of-the-art methods.


Assuntos
Processamento de Imagem Assistida por Computador , Aprendizagem
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