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1.
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.

2.
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
3.
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
4.
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
5.
Nat Genet ; 55(10): 1745-1756, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37679493

RESUMO

Exploitation of crop heterosis is crucial for increasing global agriculture production. However, the quantitative genomic analysis of heterosis was lacking, and there is currently no effective prediction tool to optimize cross-combinations. Here 2,839 rice hybrid cultivars and 9,839 segregation individuals were resequenced and phenotyped. Our findings demonstrated that indica-indica hybrid-improving breeding was a process that broadened genetic resources, pyramided breeding-favorable alleles through combinatorial selection and collaboratively improved both parents by eliminating the inferior alleles at negative dominant loci. Furthermore, we revealed that widespread genetic complementarity contributed to indica-japonica intersubspecific heterosis in yield traits, with dominance effect loci making a greater contribution to phenotypic variance than overdominance effect loci. On the basis of the comprehensive dataset, a genomic model applicable to diverse rice varieties was developed and optimized to predict the performance of hybrid combinations. Our data offer a valuable resource for advancing the understanding and facilitating the utilization of heterosis in rice.


Assuntos
Vigor Híbrido , Oryza , Humanos , Vigor Híbrido/genética , Oryza/genética , Melhoramento Vegetal , Fenótipo , Alelos
6.
Front Oncol ; 13: 1211759, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576888

RESUMO

OX40 (CD134), a member of the TNF receptor superfamily, is a widely studied costimulatory immune checkpoint. Several OX40 agonistic antibodies are in the clinical stage for cancer treatment, among which PF-04518600 is the leader and currently in phase II trial. It has been recognized that one potential mode of action for anti-OX40 antibodies is the deletion of intratumoral Tregs. Thus, a novel human anti-OX40 antibody, BAT6026, was generated with enhanced antibody dependent cellular cytotoxicity (ADCC) via fucose deletion to strengthen its Treg depletion activity. This characteristic of BAT6026 differentiates it from other previously reported anti-OX40 antibodies in the field of tumor therapy. The affinity of BT6026 to OX40 was 0.28nM, approximately 8 times stronger than that of PF-04518600. BAT6026 effectively competed for the binding of ligand OX40L to OX40, whereas PF-04518600 only partially competed. Moreover, compared to PF-04518600, BAT6026 activated T cells more effectively when clustered by FcγRs engagement and stimulated SEB-pretreated PBMCs to secrete IL-2 cytokines in vitro. In addition, BAT6026 demonstrated stronger anti-tumor activity than PF-04518600 in an OX40-humanized mouse MC38 tumor model. BAT6026 also showed a significantly synergistic effect on tumor inhibition when combined treatment with PD-1 antibody. Analysis of tumor-infiltrating T cells revealed that BAT6026 treatment significantly reduced Treg cells and increased CD8+ T cells in tumor. Preclinical safety assessment in non-human primates demonstrated a good safety profile for BAT6026. Together these data warrant further development of BAT6026 into clinical trials for patients with cancer.

7.
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.

8.
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
9.
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.

10.
Front Vet Sci ; 10: 1139089, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215473

RESUMO

Infectious bronchitis virus (IBV) is a vital pathogen in poultry farms, which can induce respiratory, nephropathogenic, oviduct, proventriculus, and intestinal diseases. Based on the phylogenetic classification of the full-length S1 gene, IBV isolates have been categorized into nine genotypes comprising 38 lineages. GI (GI-1, GI-2, GI-3, GI-4, GI-5, GI-6, GI-7, GI-13, GI-16, GI-18, GI-19, GI-22, GI-28, and GI-29), GVI-1 and GVII-1 have been reported in China in the past 60 years. In this review, a brief history of IBV in China is described, and the current epidemic strains and licensed IBV vaccine strains, as well as IBV prevention and control strategies, are highlighted. In addition, this article presents unique viewpoints and recommendations for a more effective management of IBV. The recombinant Newcastle Disease virus (NDV) vector vaccine expressed S gene of IBV QX-like and 4/91 strains may be the dominant vaccine strains against NDV and IBV.

11.
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.

12.
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
13.
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
14.
Front Endocrinol (Lausanne) ; 13: 1035929, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353235

RESUMO

Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder among women of reproductive age. Current standard treatment includes lifestyle change, oral pharmacological agents, and surgical modalities. However, the efficacy of current therapies is less than satisfactory. Clinical evidence has shown that acupuncture is effective for regulating hormone levels, promoting ovulation, and attenuating insulin resistance in patients with PCOS. Acupuncture may affect the production of ß-endorphin, which may lead to gonadotropin-releasing hormone secretion and then affect ovulation, menstrual cycle, and fertility. The mechanism of acupuncture for patients with PCOS has not been comprehensively reviewed so far. Better understanding of the mechanisms of acupuncture would help popularize the use of acupuncture therapy for patients with PCOS. In this narrative review, we aimed to overview the potential mechanisms and evidence-based data of acupuncture on PCOS, and analyze the most frequently used acupoints based on animal and clinical studies. The results of this study will contribute to a better understanding of the current situation in this field.


Assuntos
Terapia por Acupuntura , Resistência à Insulina , Síndrome do Ovário Policístico , Humanos , Animais , Feminino , Síndrome do Ovário Policístico/terapia , Síndrome do Ovário Policístico/etiologia , Terapia por Acupuntura/efeitos adversos , Terapia por Acupuntura/métodos , Ovulação
15.
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
16.
IEEE J Biomed Health Inform ; 26(12): 5907-5917, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36103444

RESUMO

This study proposed a refined BP prediction strategy that using single-channel photoplethysmography (PPG) signals to stratify populations by cardiovascular status before BP estimation. Combining demographic characteristics (age, gender) and pulse wave morphological features, the random forest was applied to screen two kinds of typical cardiovascular diseases (CVDs), with an accuracy of 92.2%. A deep learning model (BiLSTM-At) was proposed to estimate the long-term BP trend for different CVD groups. Transfer learning technique was used for personalized modeling to reduce computational complexity while improving performance. The method was validated on 255 patients with different CVDs. The mean absolute errors (MAEs) of systolic blood pressure (SBP) and diastolic blood pressure (DBP) estimation were 2.815 mmHg and 1.876 mmHg for normal subjects, 3.024 mmHg and 1.334 mmHg for AF subjects, and 4.444 mmHg and 2.549 mmHg for CA subjects. The results met the American Association for the Advancement of Medical Instrumentations (AAMI) and British Hypertension Society (BHS) Class A criteria. This indicated that our strategy has good performance and can realize long-term monitoring of BP through a small batch samples, with the potential to implement real-time monitoring in healthy devices.


Assuntos
Determinação da Pressão Arterial , Hipertensão , Humanos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Fotopletismografia/métodos , Algoritmo Florestas Aleatórias
17.
Front Med (Lausanne) ; 9: 851172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091712

RESUMO

Blood pressure is one of the basic physiological parameters of human physiology. Frequent and repeated measurement of blood pressure along with recording of environmental or other physiological parameters when measuring blood pressure may reveal important cardiovascular risk factors that can predict occurrence of cardiovascular events. Currently, wearable non-invasive blood pressure measurement technology has attracted much research attention. Several different technical routes have been proposed to solve the challenge between portability or continuity of measurement methods and medical level accuracy of measurement results. The accuracy of blood pressure measurement technology based on auscultation and oscillography has been clinically verified, while majority of other technical routes are being explored at laboratory or multi-center clinical demonstration stage. Normally, Blood pressure measurement based on oscillographic method outside the hospital can only be measured at intervals. There is a need to develop techniques for frequent and high-precision blood pressure measurement under natural conditions outside the hospital. In this paper, we discussed the current status of blood pressure measurement technology and development trends of blood pressure measurement technology in different scenarios. We focuses on the key technical challenges and the latest advances in the study of miniaturization devices based on oscillographic method at wrist and PTT related method at finger positions as well as technology processes. This study is of great significance to the application of high frequency blood pressure measurement technology.

18.
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
19.
Chem Commun (Camb) ; 58(58): 8014-8024, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35775431

RESUMO

Alkali metal-O2 batteries exhibit ultra-high theoretical energy density which is even on par with fossil energy and are expected to become the next generation energy storage devices. However, to maintain the advantages of high energy density of alkali metal-O2 batteries, the reversibility of alkali metal anodes with high capacity is of vital importance. But the alkali metal anode with high chemical activity often faces a variety of challenges, including various side reactions, dendrite formation and volume expansion. In this highlight, we focus on the challenges faced by alkali metal anodes in alkali metal-O2 batteries and introduce the latest strategies to effectively stabilize the metal anode. Future perspectives are pointed out, which are valuable for the further development of nonaqueous alkaline metal-O2 batteries.

20.
Biosens Bioelectron ; 198: 113855, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34871834

RESUMO

Simultaneous monitoring of electrophysiological and biochemical signals is of great importance in healthcare and fitness management, while the fabrication of highly integrated and flexible devices is crucial to these applications. Herein, we devised a multifunctional and flexible hydrogel-paper patch (HPP) that was capable of simultaneously real-time monitoring of electrocardiogram (ECG) signal and biochemical signal (glucose content) in sweat during exercise. The self-assembly of the highly porous PEDOT:PSS hydrogel on paper fiber provided the HPP with good conductivity and hydrophilic wettability for efficient electron transmission and substance diffusion, thereby enabling it to serve as a low-impedance ECG electrode and a highly sensitive glucose sensor. Additionally, the spontaneous capillary flow effect allows the paper patch to be used as microfluidic channels for the collect and analysis of sweat. Moreover, the HPP is integrated with a flexible printed circuit board (FPCB) and works as a multifunctional wearable device mounted on the chest for real-time monitoring of electrophysiological and biochemical signals during exercise.


Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Hidrogéis , Suor
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