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1.
Theor Appl Genet ; 137(7): 173, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937300

RESUMO

KEY MESSAGE: Genetic editing of grain size genes quickly improves three-line hybrid rice parents to increase the appearance quality and yield of hybrid rice. Grain size affects rice yield and quality. In this study, we used CRISPR/Cas9 to edit the grain size gene GW8 in the maintainer line WaitaiB (WTB) and restorer line Guanghui998 (GH998). The new slender sterile line WTEA (gw8) was obtained in the BC2F1 generation by transferring the grain mutation of the maintainer plant to the corresponding sterile line WantaiA (WTA, GW8) in the T1 generation. Two slender restorer lines, GH998E1 (gw8(II)) and GH998E2 (gw8(I)), were obtained in T1 generation. In the early stage, new sterile and restorer lines in grain mutations were created by targeted editing of GS3, TGW3, and GW8 genes. These parental lines were mated to detect the impact of grain-type mutations on hybrid rice yield and quality. Mutations in gs3, gw8, and tgw3 had a minimal impact on agronomic traits except the grain size and thousand-grain weight. The decrease in grain width in the combination mainly came from gw8/gw8, gs3/gs3 increased the grain length, gs3/gs3-gw8/gw8 had a more significant effect on the grain length, and gs3/gs3-gw8/gw8(I) contributed more to grain length than gs3/gs3-gw8/gw8(II). The heterozygous TGW3/tgw3 may not significantly increase grain length. Electron microscopy revealed that the low-chalky slender-grain variety had a cylindrical grain shape, a uniform distribution of endosperm cells, and tightly arranged starch grains. Quantitative fluorescence analysis of endospermdevelopment-related genes showed that the combination of slender grain hybrid rice caused by gs3 and gw8 mutations promoted endosperm development and improved appearance quality. An appropriate grain size mutation resulted in hybrid rice varieties with high yield and quality.


Assuntos
Sistemas CRISPR-Cas , Grão Comestível , Edição de Genes , Oryza , Oryza/genética , Oryza/crescimento & desenvolvimento , Edição de Genes/métodos , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Genes de Plantas , Fenótipo , Melhoramento Vegetal/métodos , Mutação , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Sementes/genética , Sementes/crescimento & desenvolvimento
2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
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.

9.
Biochem Biophys Res Commun ; 545: 157-163, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33550097

RESUMO

The proliferation and migration of vascular smooth muscle cells (VSMCs) is one of main reasons of vascular remodeling and is the pathogenesis of atherosclerosis and other vascular diseases. Transient receptor potential vanilloid 1 (TRPV1) is the specific receptor of capsaicin. TRPV1 has been previously reported to inhibit proliferation, migration and phenotypic switching, but the regulatory mechanisms and relevant signalling pathways are not clear. The aim of this study was to investigate the effects of capsaicin-activated TRPV1 on VSMC phenotypic switching. In this study, oxidized low density lipoprotein (ox-LDL) was used to induce the proliferation and migration of VSMCs. Our data showed that the VSMC proliferation induced by ox-LDL was dependent on the concentration of ox-LDL. Nevertheless, the data showed that capsaicin activated TRPV1 significantly decreased ox-LDL-induced superoxide anion generation. Phenotypic switching of VSMCs was inhibited by the activation of TRPV1. Furthermore, capsaicin decreased ox-LDL-induced superoxide anion generation by activating peroxisome proliferator activated receptor α (PPARα). TRPV1 inhibited VSMC phenotypic switching via upregulated expression of PPARα. It may be considered a useful target for the treatment of vascular remodeling.


Assuntos
Miócitos de Músculo Liso/metabolismo , PPAR alfa/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Capsaicina/farmacologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Lipoproteínas LDL/metabolismo , Lipoproteínas LDL/farmacologia , Camundongos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , PPAR alfa/agonistas , Fenótipo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Superóxidos/metabolismo , Canais de Cátion TRPV/agonistas , Regulação para Cima/efeitos dos fármacos , Remodelação Vascular/efeitos dos fármacos , Remodelação Vascular/fisiologia
10.
Phys Rev Lett ; 124(17): 177201, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32412280

RESUMO

Graphene can develop large magnetic moments in custom-crafted open-shell nanostructures such as triangulene, a triangular piece of graphene with zigzag edges. Current methods of engineering graphene nanosystems on surfaces succeeded in producing atomically precise open-shell structures, but demonstration of their net spin remains elusive to date. Here, we fabricate triangulenelike graphene systems and demonstrate that they possess a spin S=1 ground state. Scanning tunneling spectroscopy identifies the fingerprint of an underscreened S=1 Kondo state on these flakes at low temperatures, signaling the dominant ferromagnetic interactions between two spins. Combined with simulations based on the meanfield Hubbard model, we show that this S=1 π paramagnetism is robust and can be turned into an S=1/2 state by additional H atoms attached to the radical sites. Our results demonstrate that π paramagnetism of high-spin graphene flakes can survive on surfaces, opening the door to study the quantum behavior of interacting π spins in graphene systems.

11.
Phys Rev Lett ; 125(14): 146801, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064521

RESUMO

Graphene nanoribbons (GNRs), low-dimensional platforms for carbon-based electronics, show the promising perspective to also incorporate spin polarization in their conjugated electron system. However, magnetism in GNRs is generally associated with localized states around zigzag edges, difficult to fabricate and with high reactivity. Here we demonstrate that magnetism can also be induced away from physical GNR zigzag edges through atomically precise engineering topological defects in its interior. A pair of substitutional boron atoms inserted in the carbon backbone breaks the conjugation of their topological bands and builds two spin-polarized boundary states around them. The spin state was detected in electrical transport measurements through boron-substituted GNRs suspended between the tip and the sample of a scanning tunneling microscope. First-principle simulations find that boron pairs induce a spin 1, which is modified by tuning the spacing between pairs. Our results demonstrate a route to embed spin chains in GNRs, turning them into basic elements of spintronic devices.

12.
Nano Lett ; 19(5): 3288-3294, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30964303

RESUMO

We report on the fabrication and transport characterization of atomically precise single-molecule devices consisting of a magnetic porphyrin covalently wired by graphene nanoribbon electrodes. The tip of a scanning tunneling microscope was utilized to contact the end of a GNR-porphyrin-GNR hybrid system and create a molecular bridge between the tip and sample for transport measurements. Electrons tunneling through the suspended molecular heterostructure excited the spin multiplet of the magnetic porphyrin. The detachment of certain spin centers from the surface shifted their spin-carrying orbitals away from an on-surface mixed-valence configuration, recovering its original spin state. The existence of spin-polarized resonances in the free-standing systems and their electrical addressability is the fundamental step in the utilization of carbon-based materials as functional molecular spintronics systems.

13.
Chemphyschem ; 20(18): 2305-2310, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31328365

RESUMO

Within the collection of surface-supported reactions currently accessible for the production of extended molecular nanostructures under ultra-high vacuum, Ullmann coupling has been the most successful in the controlled formation of covalent single C-C bonds. Particularly advanced control of this synthetic tool has been obtained by means of hierarchical reactivity, commonly achieved by the use of different halogen atoms that consequently display distinct activation temperatures. Here we report on the site-selective reactivity of certain carbon-halogen bonds. We use precursor molecules halogenated with bromine atoms at two non-equivalent carbon atoms and found that the Ullmann coupling occurs on Au(111) with a remarkable predilection for one of the positions. Experimental evidence is provided by means of scanning tunneling microscopy and core level photoemission spectroscopy, and a rationalized understanding of the observed preference is obtained from density functional theory calculations.

14.
Biochem Biophys Res Commun ; 503(3): 1356-1363, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30007438

RESUMO

High-fat diet (HFD) is known to promote atherosclerosis which accelerates the development of atherosclerotic cardiovascular diseases. Vascular dysfunction characterized by inflammation and lipid accumulation is common in atherosclerosis caused by HFD. The specific effects of HFD on blood vessels and the underlying mechanisms need to be further clarified. Toll-like receptor 4 (TLR4) is a key contributing factor in atherosclerosis and TLR4 deficiency protects vascular smooth muscle cells against inflammatory responses and lipid accumulation in vitro. However, the physiological significance of TLR4 signaling in HFD-induced changes is unknown. In this study, we observed that HFD feeding increased body weight, circulating inflammatory cytokines and lipid accumulation in the aorta of wild-type mice but apart from increasing body weight, did not affect the TLR4 knockout mice. TLR4 expression increased significantly in the arterial walls after receiving HFD treatment, while that of the co-localizing PPARγ and ABCG1 markedly decreased. TLR4 deficiency reversed the HFD-induced attenuation of PPARγ and ABCG1. In conclusion, TLR4 mediates HFD induced increase in body weight, inflammation and aortic lipid accumulation through, at least partly, the PPARγ/ABCG1 signaling pathway. Therefore, interfering with TLR4 signaling is a viable therapeutic option in diet induced atherosclerosis.


Assuntos
Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Dieta Hiperlipídica/efeitos adversos , Inflamação/metabolismo , Músculo Liso Vascular/metabolismo , PPAR gama/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Ensaio de Imunoadsorção Enzimática , Inflamação/patologia , Lipídeos/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/patologia , Transdução de Sinais , Receptor 4 Toll-Like/deficiência
15.
Cereb Cortex ; 27(6): 3254-3271, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28379350

RESUMO

The ability of the brain to predict future events based on the pattern of recent sensory experience is critical for guiding animal's behavior. Neocortical circuits for ongoing processing of sensory stimuli are extensively studied, but their contributions to the anticipation of upcoming sensory stimuli remain less understood. We, therefore, used in vivo cellular imaging and fiber photometry to record mouse primary auditory cortex to elucidate its role in processing anticipated stimulation. We found neuronal ensembles in layers 2/3, 4, and 5 which were activated in relationship to anticipated sound events following rhythmic stimulation. These neuronal activities correlated with the occurrence of anticipatory motor responses in an auditory learning task. Optogenetic manipulation experiments revealed an essential role of such neuronal activities in producing the anticipatory behavior. These results strongly suggest that the neural circuits of primary sensory cortex are critical for coding predictive information and transforming it into anticipatory motor behavior.


Assuntos
Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Motivação/fisiologia , Atividade Motora/fisiologia , Rede Nervosa/fisiologia , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Animais , Córtex Auditivo/citologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Channelrhodopsins/genética , Channelrhodopsins/metabolismo , Condicionamento Clássico , Comportamento de Ingestão de Líquido , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Parvalbuminas/genética , Parvalbuminas/metabolismo , Transdução Genética , Vigília
16.
J Stroke Cerebrovasc Dis ; 27(2): 479-485, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29056405

RESUMO

BACKGROUND: In the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial, 19.1% of ischemic strokes occurred out of the territory of previously symptomatic stenosis during the mean follow-up period of 23.4 months. However, it is unknown how many ischemic strokes were due to a previously asymptomatic intracranial atherosclerotic stenosis (ICAS). The objective of this study was to investigate whether the concomitant asymptomatic ICAS influences the outcome of patients undergoing symptomatic ICAS stenting. METHODS: We retrospectively reviewed 576 consecutive patients with nondisabling ischemic stroke (modified Rankin scale score of ≤3) who were treated with symptomatic ICAS (≥70% stenosis) stenting with or without concomitant asymptomatic ICAS. The baseline characteristics and the 30-day primary end points (stroke or death after stenting) were compared by bivariate and multivariable logistic analyses. RESULTS: The 30-day rate of primary end points was 5.2%, which was higher in patients with concomitant asymptomatic ICAS (≥50% stenosis) than in those without asymptomatic ICAS (no stenosis or <50% stenosis) (8.9% versus 3.8%, P = .014). In patients with concomitant asymptomatic ICAS, 25% of ischemic strokes occurred out of the territory of the stented artery, whereas in patients without asymptomatic ICAS, no ischemic stroke occurred out of the territory of the stented artery. Multivariable analysis showed that concomitant asymptomatic ICAS was an independent risk factor for 30-day stroke (odds ratio = 2.37, 95% confidence interval, 1.14-5.63; P = .023). CONCLUSIONS: Concomitant asymptomatic ICAS (≥50% stenosis) might increase the 30-day risk of stroke in patients undergoing symptomatic ICAS stenting.


Assuntos
Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Arteriosclerose Intracraniana/terapia , Stents , Acidente Vascular Cerebral/etiologia , Doenças Assintomáticas , Distribuição de Qui-Quadrado , China , Feminino , Humanos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico , Fatores de Tempo , Resultado do Tratamento
17.
Histochem Cell Biol ; 147(4): 511-521, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27774580

RESUMO

The phenotypic modulation of contractile vascular smooth muscle cell (VSMC) is widely accepted as the pivotal process in the arterial remodeling induced by hypertension. This study aimed to investigate the potential role of transient receptor potential vanilloid type 1 (TRPV1) on regulating VSMC plasticity and intracranial arteriole remodeling in hypertension. Spontaneously hypertensive rats (SHR), Wistar-Kyoto (WKY) rats and TRPV1-/- mice on a C57BL/6J background were used. By microscopic observation of the histopathological sections of vessels from hypertensive SHR and age-matched normotensive WKY control rats, we found that hypertension induced arterial remodeling. Decreased α-smooth muscle actin (α-SMA) and SM22α while increased osteopontin (OPN) were observed in aorta and VSMCs derived from SHR compared with those in WKY, and VSMCs derived from SHR upregulated inflammatory factors. TRPV1 activation by capsaicin significantly increased expression of α-SMA and SM22α, reduced expression of OPN, retarded proliferative and migratory capacities and inhibited inflammatory status in VSMCs from SHR, which was counteracted by TRPV1 antagonist 5'-iodoresiniferatoxin (iRTX) combined with capsaicin. TRPV1 activation by capsaicin ameliorated intracranial arteriole remodeling in SHR and deoxycorticosterone acetate (DOCA)-salt hypertensive mice. However, the attenuation of arteriole remodeling by capsaicin was not observed in TRPV1-/- mice. Furthermore, TRPV1 activation significantly decreased the activity of PI3K and phosphorylation level of Akt in SHR-derived VSMCs. Taken together, we provide evidence that TRPV1 activation by capsaicin attenuates intracranial arteriole remodeling through inhibiting VSMC phenotypic modulation during hypertension, which may be at least partly attributed to the suppression PI3K/Akt signaling pathway. These findings highlight the prospect of TRPV1 in prevention and treatment of hypertension.


Assuntos
Arteríolas/metabolismo , Hipertensão/metabolismo , Modelos Biológicos , Músculo Liso Vascular/metabolismo , Canais de Cátion TRPV/metabolismo , Remodelação Vascular , Animais , Pressão Intracraniana , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Canais de Cátion TRPV/deficiência
18.
Cell Tissue Res ; 368(1): 145-157, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27807703

RESUMO

Toll-like receptor 4 (TLR4) plays critical roles in vascular inflammation, lipid accumulation and atherosclerosis development. However, the mechanisms underlying these processes are still not well established, especially in vascular smooth muscle cells (VSMCs). ATP-binding cassette transporter G1 (ABCG1) is one of the key genes mediating inflammation and cellular lipid accumulation. The function of TLR4 in regulating the expression of ABCG1 and the underlying molecular mechanisms remain to be elucidated. In this study, we cultured VSMCs from the thoracic aortas of mice and treated the cells with 50 µg/ml oxidized low-density lipoprotein (oxLDL) to activate TLR4 signaling. We observed that activating TLR4 with oxLDL induced inflammatory responses and lipid accumulation in VSMCs. The expression of peroxisome proliferator-activated receptor gamma (PPARγ), liver X receptor alpha (LXRα) and ABCG1 was inhibited by TLR4 activation. However, these effects could be reversed by knocking out TLR4. PPARγ activation by rosiglitazone rescued LXRα and ABCG1 expression and reduced TLR4-induced inflammation and lipid accumulation. Silencing PPARγ expression with a specific small interfering RNA (siRNA) inhibited LXRα and ABCG1 expression and, importantly, enhanced TLR4-induced inflammation and lipid accumulation. In conclusion, ABCG1 expression was down-regulated by TLR4, which induces inflammation and lipid accumulation in VSMCs via PPARγ/LXRα signaling. These findings indicate a novel molecular mechanism underlying TLR4-induced inflammation and lipid accumulation.


Assuntos
Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Inflamação/patologia , Metabolismo dos Lipídeos , Receptores X do Fígado/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , PPAR gama/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Regulação para Baixo/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Camundongos Knockout , Modelos Biológicos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Rosiglitazona , Transdução de Sinais/efeitos dos fármacos , Tiazolidinedionas/farmacologia , Receptor 4 Toll-Like/deficiência
19.
Cereb Cortex ; 26(9): 3690-3704, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27405333

RESUMO

Glial precursor transplantation provides a potential therapy for brain disorders. Before its clinical application, experimental evidence needs to indicate that engrafted glial cells are functionally incorporated into the existing circuits and become essential partners of neurons for executing fundamental brain functions. While previous experiments supporting for their functional integration have been obtained under in vitro conditions using slice preparations, in vivo evidence for such integration is still lacking. Here, we utilized in vivo two-photon Ca(2+) imaging along with immunohistochemistry, fluorescent indicator labeling-based axon tracing and correlated light/electron microscopy to analyze the profiles and the functional status of glial precursor cell-derived astrocytes in adult mouse neocortex. We show that after being transplanted into somatosensory cortex, precursor-derived astrocytes are able to survive for more than a year and respond with Ca(2+) signals to sensory stimulation. These sensory-evoked responses are mediated by functionally-expressed nicotinic receptors and newly-established synaptic contacts with the host cholinergic afferents. Our results provide in vivo evidence for a functional integration of transplanted astrocytes into adult mammalian neocortex, representing a proof-of-principle for sensory cortex remodeling through addition of essential neural elements. Moreover, we provide strong support for the use of glial precursor transplantation to understand glia-related neural development in vivo.


Assuntos
Astrócitos/fisiologia , Astrócitos/transplante , Sinalização do Cálcio/fisiologia , Estimulação Elétrica/métodos , Neocórtex/citologia , Neocórtex/fisiologia , Córtex Somatossensorial/fisiologia , Potenciais de Ação/fisiologia , Animais , Astrócitos/citologia , Diferenciação Celular/fisiologia , Feminino , Humanos , Masculino , Camundongos , Neocórtex/cirurgia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Células-Tronco Neurais/transplante , Transdução de Sinais/fisiologia
20.
Histochem Cell Biol ; 145(2): 119-30, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26708152

RESUMO

The fully differentiated medial vascular smooth muscle cells (VSMCs) of mature vessels keep quiescent and contractile. However, VSMC can exhibit the plasticity in phenotype switching from a differentiated and contractile phenotype to a dedifferentiated state in response to alterations in local environmental cues, which is called phenotypic modulation or switching. Distinguishing from its differentiated state expressing more smooth muscle (SM)-specific/selective proteins, the phenotypic modulation in VSMC is characterized by an increased rate of proliferation, migration, synthesis of extracellular matrix proteins and decreased expression of SM contractile proteins. Although it has been well demonstrated that phenotypic modulation of VSMC contributes to the occurrence and progression of many proliferative vascular diseases, little is known about the details of the molecular mechanisms of VSMC phenotypic modulation. Growing evidence suggests that variety of molecules including microRNAs, cytokines and biochemical factors, membrane receptors, ion channels, cytoskeleton and extracellular matrix play important roles in controlling VSMC phenotype. The focus of the present review is to provide an overview of potential molecular mechanisms involved in VSMC phenotypic modulation in recent years. To clarify VSMC differentiation and phenotypic modulation mechanisms will contribute to producing cell-based therapeutic interventions for aberrant VSMC differentiation-related diseases.


Assuntos
Músculo Liso Vascular/metabolismo , Fenótipo , Animais , Diferenciação Celular , Humanos , Músculo Liso Vascular/patologia
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