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1.
Adv Mater ; : e2401955, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613435

RESUMO

Unimolecular current rectifiers are fundamental building blocks in organic electronics. Rectifying behavior has been identified in numerous organic systems due to electron-hole asymmetries of orbital levels interfaced by a metal electrode. As a consequence, the rectifying ratio (RR) determining the diode efficiency remains fixed for a chosen molecule-metal interface. Here, we present a mechanically tunable molecular diode exhibiting an exceptionally large rectification ratio (>105) and reversible direction. The molecular system comprises a 7-armchair graphene nanoribbon (GNR) doped with a single unit of substitutional diboron within its structure, synthesized with atomic precision on a gold substrate by on-surface synthesis. The diboron unit creates half-populated in-gap bound states and splits the GNR frontier bands into two segments, localizing the bound state in a double barrier configuration. By suspending these GNRs freely between the tip of a low-temperature scanning tunneling microscope and the substrate, we demonstrate unipolar hole transport through the boron in-gap state's resonance. Strong current rectification is observed, associated with the varying widths of the two barriers, which can be tuned by altering the distance between tip and substrate. This study introduces an innovative approach for the precise manipulation of molecular electronic functionalities, opening new avenues for advanced applications in organic electronics. This article is protected by copyright. All rights reserved.

2.
Int Wound J ; 21(3): e14773, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38477639

RESUMO

This study aims to comprehensively compare the effects of unicondylar knee arthroplasty (UKA) and high tibial osteotomy (HTO) on wound infection and pain in patients with medial knee osteoarthritis. A computerized search was conducted in Embase, PubMed, Google Scholar, China National Knowledge Infrastructure, Cochrane Library and Wanfang databases, from database inception to October 2023, for studies comparing UKA and HTO for medial knee osteoarthritis. Studies selection, data extraction and study quality evaluation were independently conducted by two researchers. Stata 17.0 software was employed for data analysis. Overall, 10 studies involving 870 patients with medial knee osteoarthritis were included. It was found that the UKA group had significantly lower wound visual analogue scale scores compared to the HTO group (SMD = -0.53, 95%CI: -0.87 to -0.20, p < 0.001). The incidence of wound infection in the UKA group was higher than in the HTO group (OR = 1.92, 95%CI: 0.65-5.69, p = 0.240), and the incidence of complications was lower (OR = 0.89, 95%CI: 0.52-1.54, p = 0.684), though these differences were not statistically significant. This study indicates that UKA is effective in alleviating postoperative wound pain in medial knee osteoarthritis. However, the rates of postoperative wound infection and complications are comparable to those of HTO. Clinicians should consider factors such as patient age and disease severity in making individualized treatment decisions.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Humanos , Infecção da Ferida Cirúrgica , Dor Pós-Operatória , Osteotomia
3.
Medicine (Baltimore) ; 103(5): e37113, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38306511

RESUMO

The purpose of this study is to investigate whether the presentation of targets can affect the performance of multiple object tracking and whether the difference between female soccer players and female college students is regulated by the presentation of targets. We enlisted a group of 20 Chinese female soccer players and another group of 20 non-players to complete a multiple object juggling (MOJ) task. The mean age was 20.24 ±â€…1.61 years in the athletes group and 21.35 ±â€…1.93 years in the non-athletes group. Accuracy was analyzed to examine the disparity between soccer players and non-players, as well as the disparity between 3 presentation conditions for targets (fixed, added, and dynamic). Regarding the MOJ task, female soccer players did not outperform non-players (F = 1.84, 95% CI [-1.14 to 6.02], P = .27). The performance of tracking in fixed conditions was superior to that in added and dynamic conditions (MD = 10.33%, 95% CI [4.93 to 15.71], P < .001; MD = 9.82%, 95% CI [4.43 to 15.21], P < .001). The tracking accuracy of female soccer players was significantly higher than non-players in dynamic condition (F = 7.26, 95% CI [2.19 to 14.59], P = .01). According to the findings, experts who specialize in team sports tend to exhibit a greater attention advantage in areas that are pertinent to their field of expertise. For future studies, it will be necessary to employ MOT conditions that are more representative of sport-specific characteristics to strengthen the task ecological validity.


Assuntos
Futebol , Esportes , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Atletas
4.
PLoS One ; 19(2): e0296819, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38377109

RESUMO

The escalating challenge of municipal solid waste (MSW) critically tests the sustainable development capacities of urban centers. In response, China initiated pilot policies in 2017 aimed at bolstering MSW management. The effectiveness of these initiatives, however, necessitates empirical scrutiny. This study leverages panel data spanning 95 cities at the prefectural level or higher, covering the period from 2006 to 2020, to assess the impact of the MSW sorting pilot policy on urban sustainable development using a difference-in-differences approach. The research found that the MSW sorting pilot policy has significantly increased the processing volume of MSW, thereby enhancing the sustainable development capabilities of cities. Further, the study identifies augmented fixed asset investments as a key mechanism through which pilot cities have enhanced their MSW management capabilities. Notably, the policy's stimulative effects are more pronounced in less densely populated and economically lagging regions. These findings provide critical insights for developing nations in shaping MSW sorting strategies and advancing urban sustainability.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Resíduos Sólidos/análise , Cidades , Crescimento Sustentável , China , Políticas
5.
Genomics ; 115(6): 110745, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37977332

RESUMO

Grain qualities including milling quality, appearance quality, eating and cooking quality, and nutritional quality are important indicators in rice breeding. Significant achievements in genetic improvement of rice quality have been made. In this study, we analyzed the variation patterns of 16 traits in 1570 rice varieties and found significant improvements in appearance quality and eating and cooking quality, particularly in hybrid rice. Through genome-wide association study and allelic functional nucleotide polymorphisms analysis of quality trait genes, we found that ALK, FGR1, FLO7, GL7/GW7, GLW7, GS2, GS3, ONAC129, OsGRF8, POW1, WCR1, and Wx were associated with the genetic improvement of rice quality traits in Southern China. Allelic functional nucleotide polymorphisms analysis of 13 important rice quality genes, including fragrance gene fgr, were performed using the polymerase chain reaction amplification refractory mutation system technology. The results showed that Gui516, Gui569, Gui721, Ryousi, Rsimiao, Rbasi, and Yuehui9802 possessed multiple superior alleles. This study elucidates the phenotypic changes and molecular basis of key quality traits of varieties in Southern China. The findings will provide guidance for genetic improvement of rice quality and the development of new varieties.


Assuntos
Oryza , Locos de Características Quantitativas , Oryza/genética , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Nucleotídeos
6.
Heliyon ; 9(8): e18516, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37560651

RESUMO

Background and purpose: Sex difference in cerebral atherosclerosis has been noted in previous studies, but the precise characteristics remain incompletely elucidated. This study aims to identify the sex difference in patients with asymptomatic cerebrovascular stenosis. Materials and methods: The image and clinical data of 1305 consecutive patients who had head and neck computed tomography angiography (CTA) were collected. Fifty hundred and seventy-three patients (287 males) with asymptomatic atherosclerotic stenosis in cerebral arteries were finally included. The stenosis number, distribution, severity and their changes with age were analyzed and compared between males and females. Simple linear regression was used to assess the change in lesions with age. Results: A total of 2097 stenoses were identified in 573 patients, males had more stenoses than females (3 [2, 5] vs 3 [2, 4], p=0.015). The number of stenoses in extracranial arteries was much higher in males (p = 0.001). Females had higher percentage of stenosis in anterior (89.6% vs 85.9%, p = 0.012) and intracranial arteries (63.3% vs 57.1%, p = 0.004) than males. Males had higher percentage of moderate-severe stenosis (5.1% vs 3.2%, p = 0.026). Age (OR = 1.67; 95% CI 1.24-2.25; p < 0.001) and hypertension (OR = 2.53; 95% CI 1.24-5.15; p = 0.01) were associated with moderate-severe stenosis. In patients over 50 years old, the number of stenoses increased by 1.03 per 10 years (p < 0.001), with 0.72 more stenoses in males (p = 0.003). Conclusions: Cerebral atherosclerotic stenosis was different between sexes regarding the distribution, severity and the change pattern with age, which underline the sex specific management in patients with cerebral atherosclerosis.

7.
Proteomics ; 23(18): e2200538, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37376803

RESUMO

Grain size is one of the most important agronomic traits for grain yield determination in rice. To better understand the proteins that are regulated by the grain size regulatory gene OsMKK3, this gene was knocked out using the CRISPR/Cas9 system, and tandem mass tag (TMT) labeling combined with liquid chromatograph-tandem mass spectrometry analysis was performed to study the regulation of proteins in the panicle. Quantitative proteomic screening revealed a total of 106 differentially expressed proteins (DEPs) via comparison of the OsMKK3 mutant line to the wild-type YexiangB, including 15 and 91 up-regulated and down-regulated DEPs, respectively. Pathway analysis revealed that DEPs were enriched in metabolic pathways, biosynthesis of secondary metabolites, phenylpropanoid biosynthesis, and photosynthesis. Strong interactions were detected among seven down-regulated proteins related to photosystem components in the protein-protein interaction network, and photosynthetic rate was decreased in mutant plants. The results of the liquid chromatography-parallel reaction monitoring/mass spectromery analysis and western blot analysis were consistent with the results of the proteomic analysis, and the results of the quantitative reverse transcription polymerase chain reaction analysis revealed that the expression levels of most candidate genes were consistent with protein levels. Overall, OsMKK3 controls grain size by regulating the protein content in cells. Our findings provide new candidate genes that will aid the study of grain size regulatory mechanisms associated with the mitogen-activated protein kinase (MAPK) signaling pathway.


Assuntos
Oryza , Oryza/metabolismo , Proteômica/métodos , Sistemas CRISPR-Cas/genética , Grão Comestível/metabolismo , Fotossíntese/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
8.
Adv Fiber Mater ; : 1-14, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37361108

RESUMO

Wearable sensors have drawn vast interest for their convenience to be worn on body to monitor and track body movements or exercise activities in real time. However, wearable electronics rely on powering systems to function. Herein, a self-powered, porous, flexible, hydrophobic and breathable nanofibrous membrane based on electrospun polyvinylidene fluoride (PVDF) nanofiber has been developed as a tactile sensor with low-cost and simple fabrication for human body motion detection and recognition. Specifically, effects of multi-walled carbon nanotubes (CNT) and barium titanate (BTO) as additives to the fiber morphology as well as mechanical and dielectric properties of the piezoelectric nanofiber membrane were investigated. The fabricated BTO@PVDF piezoelectric nanogenerator (PENG) exhibits the high ß-phase content and best overall electrical performances, thus selected for the flexible sensing device assembly. Meanwhile, the nanofibrous membrane demonstrated robust tactile sensing performance that the device exhibits durability over 12,000 loading test cycles, holds a fast response time of 82.7 ms, responds to a wide pressure range of 0-5 bar and shows a high relative sensitivity, especially in the small force range of 11.6 V/bar upon pressure applied perpendicular to the surface. Furthermore, when attached on human body, its unique fibrous and flexible structure offers the tactile sensor to present as a health care monitor in a self-powered manner by translating motions of different movements to electrical signals with various patterns or sequences. Supplementary Information: The online version contains supplementary material available at 10.1007/s42765-023-00282-8.

9.
BMC Plant Biol ; 23(1): 256, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37189032

RESUMO

BACKGROUND: Heat stress threatens rice yield and quality at flowering stage. In this study, average relative seed setting rate under heat stress (RHSR) and genotypes of 284 varieties were used for a genome-wide association study. RESULTS: We identified eight and six QTLs distributed on chromosomes 1, 3, 4, 5, 7 and 12 in the full population and indica, respectively. qHTT4.2 was detected in both the full population and indica as an overlapping QTL. RHSR was positively correlated with the accumulation of heat-tolerant superior alleles (SA), and indica accession contained at least two heat-tolerant SA with average RHSR greater than 43%, meeting the needs of stable production and heat-tolerant QTLs were offer yield basic for chalkiness degree, amylose content, gel consistency and gelatinization temperature. Chalkiness degree, amylose content, and gelatinization temperature under heat stress increased with accumulation of heat-tolerant SA. Gel consistency under heat stress decreased with polymerization of heat-tolerant SA. The study revealed qHTT4.2 as a stable heat-tolerant QTL that can be used for breeding that was detected in the full population and indica. And the grain quality of qHTT4.2-haplotype1 (Hap1) with chalk5, wx, and alk was better than that of qHTT4.2-Hap1 with CHALK5, WX, and ALK. Twelve putative candidate genes were identified for qHTT4.2 that enhance RHSR based on gene expression data and these genes were validated in two groups. Candidate genes LOC_Os04g52830 and LOC_Os04g52870 were induced by high temperature. CONCLUSIONS: Our findings identify strong heat-tolerant cultivars and heat-tolerant QTLs with great potential value to improve rice tolerance to heat stress, and suggest a strategy for the breeding of yield-balance-quality heat-tolerant crop varieties.


Assuntos
Oryza , Oryza/genética , Oryza/metabolismo , Estudo de Associação Genômica Ampla , Alelos , Amilose/metabolismo , Melhoramento Vegetal , Receptores Proteína Tirosina Quinases/genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-36901667

RESUMO

Green credit is a vital instrument for promoting low-carbon transition. However, designing a reasonable development pattern and efficiently allocating limited resources has become a challenge for developing countries. The Yellow River Basin, a critical component of the low-carbon transition in China, is still in the early stages of green credit development. Most cities in this region lack green credit development plans that suit their economic conditions. This study examined the impact of green credit on carbon emission intensity and utilized a k-means clustering algorithm to categorize the green credit development patterns of 98 prefecture-level cities in the Yellow River Basin based on four static indicators and four dynamic indicators. Regression results based on city-level panel data from 2006 to 2020 demonstrated that the development of green credit in the Yellow River Basin can effectively reduce local carbon emission intensity and promote low-carbon transition. We classified the development patterns of green credit in the Yellow River Basin into five types: mechanism construction, product innovation, consumer business expansion, rapid growth, and stable growth. Moreover, we have put forward specific policy suggestions for cities with different development patterns. The design process of this green credit development patterns is characterized by its ability to achieve meaningful outcomes while relying on fewer numbers of indicators. Furthermore, this approach boasts a significant degree of explanatory power, which may assist policy makers in comprehending the underlying mechanisms of regional low-carbon governance. Our findings provide a new perspective for the study of sustainable finance.


Assuntos
Pessoal Administrativo , Rios , Humanos , Cidades , Algoritmos , Carbono , China , Desenvolvimento Econômico
11.
Biosensors (Basel) ; 13(2)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36831971

RESUMO

A mask serves as a simple external barrier that protects humans from infectious particles from poor air conditions in the surrounding environment. As an important personal protective equipment (PPE) to protect our respiratory system, masks are able not only to filter pathogens and dust particles but also to sense, reflect or even respond to environmental conditions. This smartness is of particular interest among academia and industries due to its potential in disease detection, health monitoring and caring aspects. In this review, we provide an overlook of the current air filtration strategies used in masks, from structural designs to integrated functional modules that empower the mask's ability to sense and transfer physiological or environmental information to become smart. Specifically, we discussed recent developments in masks designed to detect macroscopic physiological signals from the wearer and mask-based disease diagnoses, such as COVID-19. Further, we propose the concept of next-generation smart masks and the requirements from material selection and function design perspectives that enable masks to interact and play crucial roles in health-caring wearables.


Assuntos
COVID-19 , Dispositivos de Proteção Respiratória , Dispositivos Eletrônicos Vestíveis , Humanos , Pandemias , Atenção à Saúde
12.
Biosensors (Basel) ; 13(1)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36671962

RESUMO

The current physical health care system has gradually evolved into a form of virtual hospitals communicating with sensors, which can not only save time but can also diagnose a patient's physical condition in real time. Textile-based wearable sensors have recently been identified as detection platforms with high potential. They are developed for the real-time noninvasive detection of human physiological information to comprehensively analyze the health status of the human body. Sweat comprises various chemical compositions, which can be used as biomarkers to reflect the relevant information of the human physiology, thus providing references for health conditions. Combined together, textile-based sweat sensors are more flexible and comfortable than other conventional sensors, making them easily integrated into the wearable field. In this short review, the research progress of textile-based flexible sweat sensors was reviewed. Three mechanisms commonly used for textile-based sweat sensors were firstly contrasted with an introduction to their materials and preparation processes. The components of textile-based sweat sensors, which mainly consist of a sweat transportation channel and collector, a signal-selection unit, sensing elements and sensor integration and communication technologies, were reviewed. The applications of textile-based sweat sensors with different mechanisms were also presented. Finally, the existing problems and challenges of sweat sensors were summarized, which may contribute to promote their further development.


Assuntos
Suor , Dispositivos Eletrônicos Vestíveis , Humanos , Suor/química , Têxteis , Biomarcadores/análise
13.
J Proteomics ; 270: 104745, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36220543

RESUMO

Grain length is one of the most important rice grain appearance components. To better understand the protein regulated by grain length in indica rice, the tandem mass tag (TMT) labeling combined with LC-MS/MS analysis was used for quantitative identification of differentially regulated proteins by comparing six long-grain cultivars (MeiB, LongfengB, YexiangB, FengtianB, WantaiB, and DingxiangB) to the short-grain cultivar BoB, respectively. A total of 6622 proteins were detected for quantitative analysis by comparing protein content of six long-grain cultivars to the short-grain cultivar, and 715 proteins were significantly regulated, consisting of 336 uniquely over-accumulated proteins and 355 uniquely down-accumulated proteins. KEGG pathway analysis revealed that most of accumulated proteins are involved in metabolic pathways, biosynthesis of secondary metabolites and phenylpropanoid biosynthesis. Four down-accumulated proteins maybe involved in the signaling pathways for grain length regulation. LC-PRM/MS quantitative analysis was used to analyze 10 differentially expressed proteins. The results were almost consistent with the TMT quantitative analysis. qRT-PCR analysis results showed that the transcription level was not always parallel to the protein content. This study identified many novel grain length accumulated proteins through the quantitative proteomics approach, providing candidate genes for further study of grain size regulatory mechanisms. SIGNIFICANCE: Rice grain length is one of the most important characteristics influencing appearance and yield. Six long-grain cultivars (MeiB, LongfengB, YexiangB, FengtianB, WantaiB, and DingxiangB obtained in Guangxi province of China from the 2000s to 2020s) and one short-grain cultivar (BoB obtained in Guangxi province of China in 1980s) were used for comparative analyses. Totally, 715 differentially expressed proteins (DEPs) were identified using TMT-base proteomic analysis. The numbers of DEPs increased as the grain length increased. 4 DEPs may be related to rice's signaling pathways for grain size regulation. A total of 85 DEPs regulated in at least four long-grain cultivars compared with the short-grain cultivar BoB, and 7 proteins were over-accumulated, and 3 proteins were down-accumulated in six long-grain cultivars. These findings provide valuable information to better understand the mechanisms of protein regulation by grain length in rice.


Assuntos
Oryza , Oryza/genética , Oryza/metabolismo , Proteômica/métodos , Cromatografia Líquida , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Espectrometria de Massas em Tandem , China , Grão Comestível/metabolismo , Transdução de Sinais
14.
Breed Sci ; 72(2): 150-168, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36275934

RESUMO

Low temperature is one of the important environmental factors that affect rice growth and yield. To better understand the japonica rice responses to cold stress, isobaric tags for a relative and absolute quantification (iTRAQ) labeling-based quantitative proteomics approach was used to detected changes in protein levels. Two-week-old seedlings of the cold tolerant rice variety Kongyu131 were treated at 8°C for 24, 48 and 72 h, then the total proteins were extracted from tissues and used for quantitative proteomics analysis. A total of 5082 proteins were detected for quantitative analysis, of which 289 proteins were significantly regulated, consisting of 169 uniquely up-regulated proteins and 125 uniquely down-regulated proteins in cold stress groups relative to the control group. Functional analysis revealed that most of the regulated proteins are involved in photosynthesis, metabolic pathway, biosynthesis of secondary metabolites and carbon metabolism. Western blot analysis showed that protein regulation was consistent with the iTRAQ data. The corresponding genes of 25 regulated proteins were used for quantitative real time PCR analysis, and the results showed that the mRNA level was not always parallel to the corresponding protein level. The importance of our study is that it provides new insights into cold stress responses in rice with respect to proteomics and provides candidate genes for cold-tolerance rice breeding.

15.
ACS Nano ; 16(9): 14819-14826, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36037149

RESUMO

Spin-hosting graphene nanostructures are promising metal-free systems for elementary quantum spintronic devices. Conventionally, spins are protected from quenching by electronic band gaps, which also hinder electronic access to their quantum state. Here, we present a narrow graphene nanoribbon substitutionally doped with boron heteroatoms that combines a metallic character with the presence of localized spin 1/2 states in its interior. The ribbon was fabricated by on-surface synthesis on a Au(111) substrate. Transport measurements through ribbons suspended between the tip and the sample of a scanning tunneling microscope revealed their ballistic behavior, characteristic of metallic nanowires. Conductance spectra show fingerprints of localized spin states in the form of Kondo resonances and inelastic tunneling excitations. Density functional theory rationalizes the metallic character of the graphene nanoribbon due to the partial depopulation of the valence band induced by the boron atoms. The transferred charge builds localized magnetic moments around the boron atoms. The orthogonal symmetry of the spin-hosting state's and the valence band's wave functions protects them from mixing, maintaining the spin states localized. The combination of ballistic transport and spin localization into a single graphene nanoribbon offers the perspective of electronically addressing and controlling carbon spins in real device architectures.

16.
Nano Lett ; 22(15): 6075-6082, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35895892

RESUMO

Molecular spins on surfaces potentially used in quantum information processing and data storage require long spin excitation lifetimes. Normally, coupling of the molecular spin with the conduction electrons of metallic surfaces causes fast relaxation of spin excitations. However, the presence of superconducting pairing effects in the substrate can protect the excited spin from decaying. In this work, we show that a proximity-induced superconducting gold film can sustain spin excitations of a FeTPP-Cl molecule for more than 80 ns. This long value was determined by studying inelastic spin excitations of the S = 5/2 multiplet of FeTPP-Cl on Au films over V(100) using scanning tunneling spectroscopy. The spin lifetime decreases with increasing film thickness, along with the decrease of the effective superconducting gap. Our results elucidate the use of proximitized gold electrodes for addressing quantum spins on surfaces, envisioning new routes for tuning the value of their spin lifetime.


Assuntos
Ouro , Supercondutividade , Fenômenos Físicos , Análise Espectral
17.
Neuropathology ; 42(6): 505-511, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35723632

RESUMO

Mutations in MARS gene cause dominant Charcot-Marie-Tooth disease (CMT) 2U. The aim of this study is to investigate phenotypic heterogeneities and peripheral neuropathology of MARS-related CMT patients. We identified a heterozygous p. R199Q mutation and an already reported heterozygous p. P800T mutation of MARS gene in two unrelated families using targeted next-generation sequencing. The first pedigree comprised three patients over three generations and the second pedigree comprised two patients over two generations. In addition of an asymptomatic carrier in the second pedigree, all patients presented with childhood-onset length dependent sensorimotor neuropathy with pes cavus. Nerve conduction studies revealed slowing of motor nerve conduction velocities (MNCV) of the median nerve indicating intermediate neuropathy in the patient with the p. R199Q mutation, and normal MNCV with reduced compound muscle action potential indicating axonal neuropathy in the patient with the p. P800T mutation. Magnetic resonance imaging detected a pattern of nerve changes similar to those in demyelinating polyneuropathies in intermediate type (p. R199Q mutation) patients compared with normal in the axonal type (p. P800T mutation) patients. Additionally, sural nerve biopsy revealed loss of myelinated axons with onion bulb formation in both mutations. By electron microscopy, a marked decrease of myelinated and unmyelinated fiber, neurofilaments aggregate with degenerating mitochondria and microtubule loss in axons were frequently found. Denervated Schwann cell complexes and few collagen pockets indicated involvement of unmyelinated Schwann cells. Therefore, the investigated MARS mutations cause not only the known axonal type but also intermediate type neuropathy with involvement of both axons and Schwann cells. Those findings are useful for the differential diagnosis of CMT patients with unknown MARS variants.


Assuntos
Doença de Charcot-Marie-Tooth , Humanos , Criança , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/patologia , Nervo Sural/patologia , Fenótipo , Linhagem , Mutação
18.
Front Plant Sci ; 12: 784037, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899812

RESUMO

Rice (Oryza sativa L.) is an important staple food crop for more than half of the world's population. Enhancing the grain quality and yield of rice to meet growing demand remains a major challenge. Here, we show that OsMKK3 encode a MAP kinase kinase that controls grain size and chalkiness by affecting cell proliferation in spikelet hulls. We showed that OsSPL16, GS5, and GIF1 have a substantial effect on the OsMKK3-regulated grain size pathway. OsMKK3 has experienced strong directional selection in indica and japonica. Wild rice accessions contained four OsMKK3 haplotypes, suggesting that the OsMKK3 haplotypes present in cultivated rice likely originated from different wild rice accessions during rice domestication. OsMKK3-Hap1, gs3, and gw8 were polymerized to enhance the grain length. Polymerization of beneficial alleles, such as OsMKK3-Hap1, gs3, gw8, fgr, alk, chalk5, and wx, also improved the quality of hybrid rice. Overall, the results indicated that beneficial OsMKK3 alleles could be used for genomic-assisted breeding for rice cultivar improvement and be polymerized with other beneficial alleles.

19.
Nat Commun ; 12(1): 5538, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545075

RESUMO

Precise control over the size and shape of graphene nanostructures allows engineering spin-polarized edge and topological states, representing a novel source of non-conventional π-magnetism with promising applications in quantum spintronics. A prerequisite for their emergence is the existence of robust gapped phases, which are difficult to find in extended graphene systems. Here we show that semi-metallic chiral GNRs (chGNRs) narrowed down to nanometer widths undergo a topological phase transition. We fabricated atomically precise chGNRs of different chirality and size by on surface synthesis using predesigned molecular precursors. Combining scanning tunneling microscopy (STM) measurements and theory simulations, we follow the evolution of topological properties and bulk band gap depending on the width, length, and chirality of chGNRs. Our findings represent a new platform for producing topologically protected spin states and demonstrate the potential of connecting chiral edge and defect structure with band engineering.

20.
Medicine (Baltimore) ; 100(4): e24384, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33530233

RESUMO

RATIONALE: Anti-IgLON5 disease was first described as a progressive antibody-associated encephalopathy, with multiple non-specific clinical symptoms including sleep dysfunction, bulbar symptoms, progressive supranuclear palsy-like syndrome, cognitive impairment, and a variety of movement disorders. This newly discovered disease presents with unremarkable or unspecific brain magnetic resonance imagings (MRI), and have poor responsiveness to immunotherapy. PATIENT CONCERNS: In this case, a 37-year-old man presented with 4-day history of gait instability, dysarthria, and oculomotor abnormalities. The initial neurologic examination revealed mild unsteady gait, subtle dysarthria, and left abducent paralysis. DIAGNOSIS: The patient was diagnosed with anti-IgLON5 disease, based on clinical features and positive anti-IgLON5 antibodies in serum. INTERVENTIONS: Initially, the patient was treated with high dosages of methylprednisolone and immunoglobulins.Outcomes: The symptoms of patient rapidly improved after high-dose intravenous methylprednisolone and immunoglobulins. CONCLUSIONS: In this paper, we report a new case of anti-IgLON5 disease with major symptoms of gait instability, dysarthria, and oculomotor abnormalities, with distinctive brain MRI findings, and responsive to immunotherapy.


Assuntos
Autoanticorpos/sangue , Doenças Autoimunes do Sistema Nervoso/diagnóstico por imagem , Moléculas de Adesão Celular Neuronais/imunologia , Encefalite/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Autoanticorpos/imunologia , Doenças Autoimunes do Sistema Nervoso/tratamento farmacológico , Doenças Autoimunes do Sistema Nervoso/imunologia , Encéfalo/diagnóstico por imagem , Disartria/diagnóstico por imagem , Disartria/tratamento farmacológico , Disartria/imunologia , Encefalite/tratamento farmacológico , Encefalite/imunologia , Transtornos Neurológicos da Marcha/diagnóstico por imagem , Transtornos Neurológicos da Marcha/tratamento farmacológico , Transtornos Neurológicos da Marcha/imunologia , Humanos , Masculino , Neuroimagem/métodos , Doenças do Nervo Oculomotor/diagnóstico por imagem , Doenças do Nervo Oculomotor/tratamento farmacológico , Doenças do Nervo Oculomotor/imunologia
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