Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 51
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Plant Cell ; 35(11): 4002-4019, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648256

RESUMO

Heading date (flowering time), which greatly influences regional and seasonal adaptability in rice (Oryza sativa), is regulated by many genes in different photoperiod pathways. Here, we characterized a heading date gene, Early heading date 5 (Ehd5), using a modified bulked segregant analysis method. The ehd5 mutant showed late flowering under both short-day and long-day conditions, as well as reduced yield, compared to the wild type. Ehd5, which encodes a WD40 domain-containing protein, is induced by light and follows a circadian rhythm expression pattern. Transcriptome analysis revealed that Ehd5 acts upstream of the flowering genes Early heading date 1 (Ehd1), RICE FLOWERING LOCUS T 1 (RFT1), and Heading date 3a (Hd3a). Functional analysis showed that Ehd5 directly interacts with Rice outermost cell-specific gene 4 (Roc4) and Grain number, plant height, and heading date 8 (Ghd8), which might affect the formation of Ghd7-Ghd8 complexes, resulting in increased expression of Ehd1, Hd3a, and RFT1. In a nutshell, these results demonstrate that Ehd5 functions as a positive regulator of rice flowering and provide insight into the molecular mechanisms underlying heading date.


Assuntos
Flores , Oryza , Ritmo Circadiano , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Oryza/genética , Oryza/metabolismo , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Repetições WD40/genética
2.
Plant Physiol ; 192(2): 967-981, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36822628

RESUMO

Grain yield and grain quality are major determinants in modern breeding controlled by many quantitative traits loci (QTLs) in rice (Oryza sativa). However, the mechanisms underlying grain shape and quality are poorly understood. Here, we characterize a QTL for grain size and grain quality via map-based cloning from wild rice (W1943), GS10 (Grain Size on Chromosome 10), which encodes a protein with 6 tandem armadillo repeats. The null mutant gs10 shows slender and narrow grains with altered cell size, which has a pleiotropic effect on other agronomical traits. Functional analysis reveals that GS10 interacts with TUD1 (Taihu Dwarf1) and is epistatic to OsGSK2 (glycogen synthase kinase 2) through regulating grain shape and lamina joint inclination, indicating it is negatively involved in brassinosteroid (BR) signaling. Pyramiding gs10 and the grain size gene GW5 into cultivar GLA4 substantially improved grain shape and appearance quality. Natural variation analysis revealed that gs10 from the wild rice Oryza rufipogon W1943 is a rare allele across the rice population. Collectively, these findings advance our understanding of the underlying mechanism of grain shape and provide the beneficial allele of gs10 for future rice breeding and genetic improvement.


Assuntos
Brassinosteroides , Oryza , Brassinosteroides/metabolismo , Grão Comestível/genética , Oryza/genética , Fenótipo , Melhoramento Vegetal , Locos de Características Quantitativas/genética
3.
Plant Physiol ; 190(3): 1747-1762, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-35976143

RESUMO

Wild rice (Oryza rufipogon) has a lower panicle seed setting rate (PSSR) and gamete fertility than domesticated rice (Oryza sativa), but the genetic mechanisms of this phenomenon remain unknown. Here, we cloned a null allele of OsMLH1, an ortholog of MutL-homolog 1 to yeast and mammals, from wild rice O. rufipogon W1943 and revealed a 5.4-kb retrotransposon insertion in OsMLH1 is responsible for the low PSSR in wild rice. In contrast to the wild-type, a near isogenic line NIL-mlh1 exhibits defective crossover (CO) formation during meiosis, resulting in reduced pollen viability, partial embryo lethality, and low PSSR. Except for the mutant of mismatch repair gene postmeiotic segregation 1 (Ospms1), all other MutL mutants from O. sativa indica subspecies displayed male and female semi-sterility similar to NIL-mlh1, but less severe than those from O. sativa japonica subspecies. MLH1 and MLH3 did not contribute in an additive fashion to fertility. Two types of MutL heterodimers, MLH1-PMS1 and MLH1-MLH3, were identified in rice, but only the latter functions in promoting meiotic CO formation. Compared to japonica varieties, indica cultivars had greater numbers of CO events per meiosis. Our results suggest that low fertility in wild rice may be caused by different gene defects, and indica and japonica subspecies have substantially different CO rates responsible for the discrepancy between the fertility of mlh1 and mlh3 mutants.


Assuntos
Oryza , Proteínas de Saccharomyces cerevisiae , Animais , Oryza/genética , Retroelementos/genética , Saccharomyces cerevisiae/genética , Sementes/genética , Meiose/genética , Mamíferos/genética , Proteínas MutL/genética , Proteínas de Saccharomyces cerevisiae/genética
4.
Nature ; 537(7622): 629-633, 2016 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-27602511

RESUMO

Increasing grain yield is a long-term goal in crop breeding to meet the demand for global food security. Heterosis, when a hybrid shows higher performance for a trait than both parents, offers an important strategy for crop breeding. To examine the genetic basis of heterosis for yield in rice, here we generate, sequence and record the phenotypes of 10,074 F2 lines from 17 representative hybrid rice crosses. We classify modern hybrid rice varieties into three groups, representing different hybrid breeding systems. Although we do not find any heterosis-associated loci shared across all lines, within each group, a small number of genomic loci from female parents explain a large proportion of the yield advantage of hybrids over their male parents. For some of these loci, we find support for partial dominance of heterozygous locus for yield-related traits and better-parent heterosis for overall performance when all of the grain-yield traits are considered together. These results inform on the genomic architecture of heterosis and rice hybrid breeding.


Assuntos
Genes de Plantas/genética , Genoma de Planta , Vigor Híbrido/genética , Oryza/crescimento & desenvolvimento , Oryza/genética , Locos de Características Quantitativas/genética , Alelos , Cruzamentos Genéticos , Genes Dominantes , Genômica , Genótipo , Heterozigoto , Hibridização Genética , Oryza/anatomia & histologia , Fenótipo , Melhoramento Vegetal , Análise de Sequência de DNA
5.
Sensors (Basel) ; 22(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36081055

RESUMO

The ankle joint is one of the important joints of the human body to maintain the ability to walk. Diseases such as stroke and ankle osteoarthritis could weaken the body's ability to control joints, causing people's gait to be out of balance. Ankle-foot orthoses can assist users with neuro/muscular or ankle injuries to restore their natural gait. Currently, passive ankle-foot orthoses are mostly designed to fix the ankle joint and provide support for walking. With the development of materials, sensing, and control science, semi-active orthoses that release mechanical energy to assist walking when needed and can store the energy generated by body movement in elastic units, as well as active ankle-foot orthoses that use external energy to transmit enhanced torque to the ankle, have received increasing attention. This article reviews the development process of ankle-foot orthoses and proposes that the integration of new ankle-foot orthoses with rehabilitation technologies such as monitoring or myoelectric stimulation will play an important role in reducing the walking energy consumption of patients in the study of human-in-the-loop models and promoting neuro/muscular rehabilitation.


Assuntos
Órtoses do Pé , Tornozelo , Articulação do Tornozelo , Fenômenos Biomecânicos , Marcha/fisiologia , Humanos , Pesquisa , Caminhada/fisiologia
6.
Molecules ; 27(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36557783

RESUMO

Sophorae tonkinensis Radix et Rhizoma (STR) is a traditional Chinese herbal medicine. STR can reduce aminotransferase activity; however, the specific mechanism remains unclear. Here, we explored the potential therapeutic effects and hepatoprotective mechanism of STR on liver damage in mice. The chemical characteristics of the extract were characterized using ultra-high-performance liquid chromatography-tandem mass spectrometry fingerprinting, and its antioxidant capacity was verified using free radical scavenging tests. Forty-eight Kunming mice were randomly assigned into six groups. The model was made after the corresponding drug was given. The results showed that the STR water extract pretreatment significantly reduced serum aminotransferase and related liver function indicators compared with that in the model group. Furthermore, the STR water extract pretreatment significantly inhibited the apoptosis of liver cells, the level of liver high-mobility group box 1 (HMGB1), and inflammatory factors in hepatic tissue compared with that in the model group, and significantly downregulated the levels of toll-like receptor 4 (TLR4), Myeloid differentiation factor 88 (MyD88), and nuclear factor kappa B (NF-κB) compared with those in the model group. Overall, the STR water extract exerted a significant protective effect on CCL4-induced acute liver injury in this study, and the accurate active ingredients of the STR water extract will be explored in the near future.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Medicamentos de Ervas Chinesas , Sophora , Camundongos , Animais , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Tetracloreto de Carbono/toxicidade , Sophora/química , Fígado , Transaminases , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle
7.
Plant Biotechnol J ; 18(1): 185-194, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31199059

RESUMO

Heterosis, or hybrid vigour, is a predominant phenomenon in plant genetics, serving as the basis of crop hybrid breeding, but the causative loci and genes underlying heterosis remain unclear in many crops. Here, we present a large-scale genetic analysis using 5360 offsprings from three elite maize hybrids, which identifies 628 loci underlying 19 yield-related traits with relatively high mapping resolutions. Heterotic pattern investigations of the 628 loci show that numerous loci, mostly with complete-incomplete dominance (the major one) or overdominance effects (the secondary one) for heterozygous genotypes and nearly equal proportion of advantageous alleles from both parental lines, are the major causes of strong heterosis in these hybrids. Follow-up studies for 17 heterotic loci in an independent experiment using 2225 F2 individuals suggest most heterotic effects are roughly stable between environments with a small variation. Candidate gene analysis for one major heterotic locus (ub3) in maize implies that there may exist some common genes contributing to crop heterosis. These results provide a community resource for genetics studies in maize and new implications for heterosis in plants.


Assuntos
Loci Gênicos , Vigor Híbrido , Zea mays/genética , Alelos , Genoma de Planta , Heterozigoto , Fenótipo
8.
Plant Physiol ; 180(4): 2077-2090, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31138620

RESUMO

Grain size is one of the key determinants of grain yield. Although a number of genes that control grain size in rice (Oryza sativa) have been identified, the overall regulatory networks behind this process remain poorly understood. Here, we report the map-based cloning and functional characterization of the quantitative trait locus GL6, which encodes a plant-specific plant AT-rich sequence- and zinc-binding transcription factor that regulates rice grain length and spikelet number. GL6 positively controls grain length by promoting cell proliferation in young panicles and grains. The null gl6 mutant possesses short grains, whereas overexpression of GL6 results in large grains and decreased grain number per panicle. We demonstrate that GL6 participates in RNA polymerase III transcription machinery by interacting with RNA polymerase III subunit C53 and transcription factor class C1 to regulate the expression of genes involved in rice grain development. Our findings reveal a further player involved in the regulation of rice grain size that may be exploited in future rice breeding.


Assuntos
Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fatores de Transcrição/metabolismo , Alelos , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Locos de Características Quantitativas/genética , RNA Polimerase III/genética , RNA Polimerase III/metabolismo , Fatores de Transcrição/genética
9.
J Cell Physiol ; 234(9): 16178-16190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30786006

RESUMO

Ovarian cancer resistance to available medicines is a huge challenge in dire need of a solution, which makes its recurrence and mortality rate further exacerbated. A promising approach to overcome chemoresistance is drug screening from natural products. Here, we report that NK007, a (±)-tylophorine malate isolated from the Asclepiadaceae family, selectively inhibited the proliferation of A2780 and A2780 (Taxol) cells and migration of paclitaxel-sensitive and -resistant ovarian cancer cells. Interestingly, the decline of cell viability, including cell multiplication, clonality, and migration capacity was independent on cell apoptosis. At the molecular level, NK007 considerably induced G1/S arrest and upregulated the expression of phospho-p38 mitogen-activated protein kinase (p-p38MAPK). In addition, hexokinase 2 (HK2) protein degradation was considerably elevated in the presence of NK007, which resulted in the reduction of oxygen consumption rate and extracellular acidification rate. Altogether, our results indicate that NK007, an analog of tylophorine, can overcome paclitaxel (PTX) resistance through p38MAPK activation and HK2 degradation. As an effective, alternative antiresistance agent, NK007 exhibits a promising potential to treat PTX-resistant ovarian cancer.

10.
Nature ; 490(7421): 497-501, 2012 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-23034647

RESUMO

Crop domestications are long-term selection experiments that have greatly advanced human civilization. The domestication of cultivated rice (Oryza sativa L.) ranks as one of the most important developments in history. However, its origins and domestication processes are controversial and have long been debated. Here we generate genome sequences from 446 geographically diverse accessions of the wild rice species Oryza rufipogon, the immediate ancestral progenitor of cultivated rice, and from 1,083 cultivated indica and japonica varieties to construct a comprehensive map of rice genome variation. In the search for signatures of selection, we identify 55 selective sweeps that have occurred during domestication. In-depth analyses of the domestication sweeps and genome-wide patterns reveal that Oryza sativa japonica rice was first domesticated from a specific population of O. rufipogon around the middle area of the Pearl River in southern China, and that Oryza sativa indica rice was subsequently developed from crosses between japonica rice and local wild rice as the initial cultivars spread into South East and South Asia. The domestication-associated traits are analysed through high-resolution genetic mapping. This study provides an important resource for rice breeding and an effective genomics approach for crop domestication research.


Assuntos
Agricultura/história , Produtos Agrícolas/genética , Evolução Molecular , Variação Genética/genética , Genoma de Planta/genética , Mapeamento Geográfico , Oryza/genética , Cruzamento/história , Produtos Agrícolas/classificação , Produtos Agrícolas/crescimento & desenvolvimento , Genômica , História Antiga , Oryza/classificação , Oryza/crescimento & desenvolvimento , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Seleção Genética
11.
Psychol Health Med ; 23(1): 114-125, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28635309

RESUMO

To systematically review the literature to identify the impact of rheumatoid arthritis (RA) on specific female sexual function domains. A meta-analysis was performed and the related literature were searched in MEDLINE, EMBASE, Cochrane Library, CNKI, CBM and Web of Science databases, and in reference lists of articles and systematic reviews. Score of the Female Sexual Function Index (FSFI) was used as the outcome measurement, and mean differences (MD) with 95% confidence intervals (CI) were calculated. Five studies were included, including 346 women with RA and 237 healthy female controls. Each domain of the FSFI score: lubrication (MD, -2.48; 95% CI, -3.69, -1.28), orgasm-1.71 (-2.09, -1.33), sexual desire-1.27 (-1.59, -0.95), satisfaction-1.67 (-2.18, -1.16), arousal-1.83 (-2.85, -0.82), pain-1.57 (-2.43, -0.70) and the total score -8.84 (-11.88, -5.79) were lower in RA women than healthy controls. Furthermore, lubrication dimension was most severely affected especially. This meta-analysis showed that female RA patients scored lower in each dimension of FSFI, mostly in the lubrication domain. It demonstrated that targeted interventions should be done to improve their sexual function. Future well-designed researches with larger sample sizes are necessary to evaluate the potential risk factors which determine female sexual dysfunction.


Assuntos
Nível de Alerta , Artrite Reumatoide/psicologia , Orgasmo , Adulto , Artrite Reumatoide/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Satisfação Pessoal , Fatores de Risco , Inquéritos e Questionários
12.
RNA ; 21(12): 2076-87, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26464523

RESUMO

Various stable circular RNAs (circRNAs) are newly identified to be the abundance of noncoding RNAs in Archaea, Caenorhabditis elegans, mice, and humans through high-throughput deep sequencing coupled with analysis of massive transcriptional data. CircRNAs play important roles in miRNA function and transcriptional controlling by acting as competing endogenous RNAs or positive regulators on their parent coding genes. However, little is known regarding circRNAs in plants. Here, we report 2354 rice circRNAs that were identified through deep sequencing and computational analysis of ssRNA-seq data. Among them, 1356 are exonic circRNAs. Some circRNAs exhibit tissue-specific expression. Rice circRNAs have a considerable number of isoforms, including alternative backsplicing and alternative splicing circularization patterns. Parental genes with multiple exons are preferentially circularized. Only 484 circRNAs have backsplices derived from known splice sites. In addition, only 92 circRNAs were found to be enriched for miniature inverted-repeat transposable elements (MITEs) in flanking sequences or to be complementary to at least 18-bp flanking intronic sequences, indicating that there are some other production mechanisms in addition to direct backsplicing in rice. Rice circRNAs have no significant enrichment for miRNA target sites. A transgenic study showed that overexpression of a circRNA construct could reduce the expression level of its parental gene in transgenic plants compared with empty-vector control plants. This suggested that circRNA and its linear form might act as a negative regulator of its parental gene. Overall, these analyses reveal the prevalence of circRNAs in rice and provide new biological insights into rice circRNAs.


Assuntos
Oryza/genética , RNA de Plantas/genética , Transcriptoma , Sequência de Bases , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oryza/metabolismo , RNA de Plantas/metabolismo , Análise de Sequência de RNA
13.
J Med Syst ; 40(3): 56, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26645320

RESUMO

Pulse rate is one of the major physiological parameters for monitoring of cardiovascular conditions or excise states during daily life. However it is difficult to precisely measure the exact pulse rates as photoplethysmography (PPG) is easy to be affected by motion artifacts. Instead of using accelerometers followed by algorithms such as least mean square (LMS), recursive least square (RLS) and independent component analysis (ICA) or other equipment such as complex laser systems to measure displacement directly, a novel motion artifact estimation method which had lower computational complexity and higher signal dynamic range was studied and implemented, where a differential channel following green and red light PPG channels was applied to reduce the motion artifact caused by displacement of light emitting diode (LED), photo diode (PD) and tissue deformation before the analog signal was converted to digital form. A miniaturized, battery powered wrist worn artifact-resistive pulse rates monitoring system (PRMS) was presented to verify the proposed method. Four kinds of motions were performed and the results showed that the differential channel improved the morphology of the PPG signal and appeared to be artifact resistive during motions through light intensity control and high gain-phase consistency circuit design here.


Assuntos
Frequência Cardíaca/fisiologia , Monitorização Ambulatorial/instrumentação , Fotopletismografia/instrumentação , Processamento de Sinais Assistido por Computador , Punho , Algoritmos , Humanos , Modelos Teóricos , Reprodutibilidade dos Testes
14.
Comput Biol Med ; 168: 107795, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38056206

RESUMO

BACKGROUND: Physiological parameter monitoring based on photoplethysmography (PPG) detection has the advantage of fast, portable, and non-invasive. Changes in the morphology of the PPG waveform can reflect the effect of arterial elasticity changes on blood pressure (BP). However, machine learning models and non-recurrent neural network models typically ignore the time-dependency of continuous PPG data, leading to the decrease of accuracy or the increased calibration frequency. OBJECTIVE: This paper proposes a BiGRU model with attention to estimate BP trends, which uses a single-channel PPG signal combined with demographic information to estimate continuous BP trends point-by-point and to discuss the impact of calibration cycle. METHODS: This paper selects 15 typical subjects from two groups with/without cardiovascular disease (CVD) and evaluates the model performance. Regarding the calibration frequency problem, we set two modes of non-calibration and calibration to validate the results of blood pressure trends estimation. RESULTS: In the calibration mode, the estimation errors (ME ± STD) of SBP for CVD/non-CVD groups are 0.91 ± 10.58 mmHg/0.17 ± 10.06 mmHg respectively, and DBP are 0.34 ± 5.28 mmHg/-0.19 ± 5.36 mmHg; in the non-calibration mode, the estimation errors of SBP for CVD/non-CVD groups are 0.27 ± 9.87 mmHg/-0.82 ± 9.92 mmHg respectively, and DBP are -0.63 ± 3.28 mmHg/0.80 ± 4.93 mmHg. CONCLUSIONS: The results show that the proposed model has high accuracy in estimating BP levels, which is expected to achieve real-time, long-term continuous BP trends monitoring in wearable devices.


Assuntos
Determinação da Pressão Arterial , Doenças Cardiovasculares , Humanos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Fotopletismografia/métodos , Análise de Onda de Pulso
15.
Comput Biol Med ; 170: 107995, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325215

RESUMO

Surgeons and anesthesia clinicians commonly face a hemodynamic disturbance known as intraoperative hypotension (IOH), which has been linked to more severe postoperative outcomes and increases mortality rates. Increased occurrence of IOH has been positively associated with mortality and incidence of myocardial infarction, stroke, and organ dysfunction hypertension. Hence, early detection and recognition of IOH is meaningful for perioperative management. Currently, when hypotension occurs, clinicians use vasopressor or fluid therapy to intervene as IOH develops but interventions should be taken before hypotension occurs; therefore, the Hypotension Prediction Index (HPI) method can be used to help clinicians further react to the IOH process. This literature review evaluates the HPI method, which can reliably predict hypotension several minutes before a hypotensive event and is beneficial for patients' outcomes.


Assuntos
Anestesia , Hipotensão , Infarto do Miocárdio , Humanos , Complicações Intraoperatórias/diagnóstico , Complicações Intraoperatórias/epidemiologia , Hipotensão/prevenção & controle , Cuidados Críticos
16.
Front Plant Sci ; 15: 1327507, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562563

RESUMO

Introduction: Rice (Oryza sativa) serves as a vital staple crop that feeds over half the world's population. Optimizing rice breeding for increasing grain yield is critical for global food security. Heading-date-related or Flowering-time-related traits, is a key factor determining yield potential. However, traditional manual phenotyping methods for these traits are time-consuming and labor-intensive. Method: Here we show that aerial imagery from unmanned aerial vehicles (UAVs), when combined with deep learning-based panicle detection, enables high-throughput phenotyping of heading-date-related traits. We systematically evaluated various state-of-the-art object detectors on rice panicle counting and identified YOLOv8-X as the optimal detector. Results: Applying YOLOv8-X to UAV time-series images of 294 rice recombinant inbred lines (RILs) allowed accurate quantification of six heading-date-related traits. Utilizing these phenotypes, we identified quantitative trait loci (QTL), including verified loci and novel loci, associated with heading date. Discussion: Our optimized UAV phenotyping and computer vision pipeline may facilitate scalable molecular identification of heading-date-related genes and guide enhancements in rice yield and adaptation.

17.
Nat Commun ; 15(1): 2413, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499575

RESUMO

The genome's dynamic nature, exemplified by elements like extrachromosomal circular DNA (eccDNA), is crucial for biodiversity and adaptation. Yet, the role of eccDNA in plants, particularly rice, remains underexplored. Here, we identify 25,598 eccDNAs, unveiling the widespread presence of eccDNA across six rice tissues and revealing its formation as a universal and random process. Interestingly, we discover that direct repeats play a pivotal role in eccDNA formation, pointing to a unique origin mechanism. Despite eccDNA's prevalence in coding sequences, its impact on gene expression is minimal, implying its roles beyond gene regulation. We also observe the association between eccDNA's formation and minor chromosomal deletions, providing insights of its possible function in regulating genome stability. Further, we discover eccDNA specifically accumulated in rice leaves, which may be associated with DNA damage caused by environmental stressors like intense light. In summary, our research advances understanding of eccDNA's role in the genomic architecture and offers valuable insights for rice cultivation and breeding.


Assuntos
Oryza , Oryza/genética , DNA Circular/genética , Melhoramento Vegetal , DNA , Genoma
18.
Front Bioeng Biotechnol ; 11: 1006326, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37214309

RESUMO

Introduction: Human-in-the-loop optimization has made great progress to improve the performance of wearable robotic devices and become an effective customized assistance strategy. However, a lengthy period (several hours) of continuous walking for iterative optimization for each individual makes it less practical, especially for disabled people, who may not endure this process. Methods: In this paper, we provide a muscle-activity-based human-in-the-loop optimization strategy that can reduce the time spent on collecting biosignals during each iteration from around 120 s to 25 s. Both Bayesian and Covariance Matrix Adaptive Evolution Strategy (CMA-ES) optimization algorithms were adopted on a portable hip exoskeleton to generate optimal assist torque patterns, optimizing rectus femoris muscle activity. Four volunteers were recruited for exoskeleton-assisted walking trials. Results and Discussion: As a result, using human-in-the-loop optimization led to muscle activity reduction of 33.56% and 41.81% at most when compared to walking without and with the hip exoskeleton, respectively. Furthermore, the results of human-in-the-loop optimization indicate that three out of four participants achieved superior outcomes compared to the predefined assistance patterns. Interestingly, during the optimization stage, the order of the two typical optimizers, i.e., Bayesian and CMA-ES, did not affect the optimization results. The results of the experiment have confirmed that the assistance pattern generated by muscle-activity-based human-in-the-loop strategy is superior to predefined assistance patterns, and this strategy can be achieved more rapidly than the one based on metabolic cost.

19.
Front Aging Neurosci ; 15: 1109144, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875705

RESUMO

Background: In patients with acute ischemic stroke, hemorrhagic transformation (HT) is a common complication after intravenous thrombolysis (IVT). In this study, we evaluated the relationship between the ratio of C-reactive protein to albumin (CAR) before thrombolysis, HT, and functional outcomes in patients with acute ischemic stroke. Methods: We retrospectively analyzed data from 354 patients who received thrombolytic therapy at the Second Affiliated Hospital of the Wenzhou Medical University in China between July 2014 and May 2022. CAR was measured on admission, and HT was identified by cranial computed tomography (CT) within 24-36 h after treatment. Poor outcome was defined as a score on the modified Rankin Scale (mRS) > 2 at discharge. The multivariate logistic regression model was used to investigate the association between CAR, HT, and poor outcome after thrombolysis, respectively. Results: A total of 354 patients were analyzed, and their median CAR was 0.61 (interquartile range, 0.24-1.28). CAR was significantly higher in the 56 patients (15.8%) who experienced HT than in those who did not (0.94 vs. 0.56, p < 0.001), and the 131 patients (37.0%) who experienced poor outcome than in those who did not (0.87 vs. 0.43, p < 0.001). Multivariate logistic regression indicated that CAR was an independent risk factor for both HT and poor outcome. The risk of HT was significantly higher among patients whose CAR fell in the fourth quartile than among those with CAR in the first quartile (OR 6.64, 95% CI 1.83 to 24.17, p = 0.004). Patients with CAR in the third quartile were more likely to experience poor outcome (OR 3.35, 95% CI 1.32 to 8.51, p = 0.01), as were those in the fourth quartile (OR 7.33, 95% CI 2.62 to 20.50, p < 0.001), compared to patients with CAR in the first quartile. Conclusion: High ratio of C-reactive protein to albumin in individuals with ischemic stroke is associated with an increased risk of HT and poor functional outcomes after thrombolysis.

20.
ACS Appl Mater Interfaces ; 15(35): 41839-41849, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37590959

RESUMO

Carbon nanotube fibers (CNTFs) are widely utilized in flexible and wearable electronics due to their outstanding electrical and mechanical properties. However, the spinning process of CNTFs has limited the CNTs from exposure, leading to an ultralow usage efficiency of individual CNTs. Here, we propose an electrochemical expansion strategy of a single CNTF at the liquid-air interface, forming a macroscopic spindle-shaped CNTF (SS-CNTF) with an enlarged volume of up to 5000-fold upon the spindle. The obtained spindle-shaped structure endows CNTF with a high specific surface area together with excellent conductivity and good mechanical properties. Therefore, the SS-CNTF-based devices exhibit outstanding performances both in energy storage (electrical double-layer supercapacitor, energy density: 11.22 Wh kg-1, power density: 203.9 kW kg-1) and electrochemical sensing (ascorbic acid: 1.26 µA µM-1 cm-2; dopamine: 103.91 µA µM-1 cm-2; uric acid: 11.53 µA µM-1 cm-2). The novel architecture of SS-CNTF prepared by one-step electrochemical expansion at the liquid-air interface enabled its high performance in multiple applications, providing new insight into the development of CNTF-based devices.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA