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1.
Arch Virol ; 167(4): 1211-1214, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35247101

RESUMEN

Narcissus (Narcissus albidus) imported from the United States exhibited leaf chlorosis during post-entry quarantine. We employed next-generation sequencing (NGS) on symptomatic leaf samples and detected vallota mosaic virus (ValMV), belonging to the genus Potyvirus, family Potyviridae, as the viral agent. Sanger sequencing of PCR products and rapid amplification of cDNA ends based on NGS contigs revealed that ValMV is 9,451 nucleotides (nt) in length, excluding the poly(A) tail. Nucleotide and amino acid (aa) sequences of the coat protein region had over 98% identity to previously reported ValMV isolates. In each of the 10 regions encoding mature proteins, however, the sequence identity to other potyviruses was 49.5-71.9% nt and 18.3-78.9% aa, values that are below the species demarcation thresholds for the family Potyviridae. Phylogenetic analysis revealed that our ValMV isolate is most closely related to known ValMV isolates and is grouped with other potyviruses. Taken together, our results indicate that the newly isolated ValMV belongs to a distinct species in the genus Potyvirus. This study provides the first report of the complete ValMV genome sequence and the first record of this virus in narcissus.


Asunto(s)
Narcissus , Potyvirus , Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Japón , Sistemas de Lectura Abierta , Filogenia , Enfermedades de las Plantas , ARN Viral/genética , Estados Unidos
2.
Arch Virol ; 166(8): 2337-2341, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34091784

RESUMEN

Anemone mosaic virus (AnMV) and ranunculus mild mosaic virus (RanMMV) infect anemone plants, which exhibit characteristic mosaic patterns on their leaves. Employing next-generation sequencing of plant material imported from the Netherlands, the complete genome sequences of these two viruses were determined for the first time. AnMV and RanMMV have 9698 and 9537 nucleotides (nt), respectively, excluding the poly(A) tail. They share 80.0%/82.0% and 98.0%/97.0% nt/amino acid (aa) sequence identity, which is above the species demarcation value, in the previously reported AnMV and RanMMV coat protein sequences, but they share 69.0%/70.0% nt/aa sequence identity or less with other potyviruses in all 10 mature protein coding regions of the genome. Additionally, phylogenetic analysis confirmed the relationship of the AnMV and RanMMV genome sequences to previously reported partial sequences and placed them within the genus Potyvirus. These results show that these two viruses represent separate species within the genus Potyvirus.


Asunto(s)
Anemone/virología , Potyvirus/clasificación , Secuenciación Completa del Genoma/métodos , Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Japón , Países Bajos , Sistemas de Lectura Abierta , Filogenia , Filogeografía , Potyvirus/genética , Potyvirus/aislamiento & purificación , Homología de Secuencia de Aminoácido
3.
Curr Vasc Pharmacol ; 15(6): 589-598, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28460626

RESUMEN

BACKGROUND: Sugen5416 (semaxinib) is an inhibitor of the vascular endothelial growth factor (VEGF) receptor. A rat model of Pulmonary Arterial Hypertension (PAH), created with Sugen5416 and chronic hypoxia, is known to have similar histological findings to those of PAH patients. OBJECTIVE: To evaluate the pathophysiological mechanisms of cardiac remodeling due to hypoxic stress with Sugen5416 in vivo. METHODS: Male Sprague-Dawley rats were exposed to hypoxia (10 ± 1% O2) for 2 weeks after a single injection of Sugen5416 (SU-hypoxia group) or the vehicle (V-hypoxia group). RESULTS: Hypoxia elevated right ventricular (RV) systolic pressure and caused RV remodeling on Day 14. By electron microscopy, metamorphosis of capillaries with endothelial cell occlusive degeneration was observed in the RV myocardium of the SU-hypoxia group from Day 3. After reoxygenation, progressive RV remodeling with extensive degeneration of cardiomyocytes was observed in the SUhypoxia group, associated with a significant increase of oxidative stress and TUNEL-positive cells in both RV and left ventricular myocardium on Day 84. The expression of VEGF mRNA in the RV myocardium was significantly suppressed in the SU-hypoxia group on Day 3, whereas delayed activation of VEGF/extracellular signal-regulated kinase (ERK) signaling pathway on Day 14 were observed. CONCLUSION: Capillary degeneration and activation of VEGF/ERK signaling pathway might be crucial to accelerate the cardiac remodeling due to hypoxic stress with Sugen5416.


Asunto(s)
Capilares/efectos de los fármacos , Ventrículos Cardíacos/efectos de los fármacos , Hipoxia/patología , Indoles/farmacología , Pirroles/farmacología , Remodelación Ventricular/efectos de los fármacos , Animales , Presión Sanguínea/efectos de los fármacos , Capilares/patología , Modelos Animales de Enfermedad , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células Endoteliales/patología , Ventrículos Cardíacos/metabolismo , Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/patología , Hipoxia/metabolismo , Etiquetado Corte-Fin in Situ/métodos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Miocardio/metabolismo , Miocardio/patología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Estrés Oxidativo/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Factores de Crecimiento Endotelial Vascular/metabolismo
4.
J Am Chem Soc ; 137(13): 4587-91, 2015 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-25815702

RESUMEN

Substantial progress has been described in the development of asymmetric variants of the phosphine-catalyzed intermolecular [3+2] annulation of allenes with alkenes; however, there have not been corresponding advances for the intramolecular process, which can generate a higher level of complexity (an additional ring and stereocenter(s)). In this study, we describe the application of chiral phosphepine catalysts to address this challenge, thereby providing access to useful scaffolds that are found in bioactive compounds, including diquinane and quinolin-2-one derivatives, with very good stereoselectivity. The products of the [3+2] annulation can be readily transformed into structures that are even more stereochemically rich. Mechanistic studies are consistent with ß addition of the phosphepine to the allene being the turnover-limiting step of the catalytic cycle, followed by a concerted [3+2] cycloaddition to the pendant olefin.


Asunto(s)
Alquenos/química , Fosfinas/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Catálisis , Estereoisomerismo
5.
Angew Chem Int Ed Engl ; 53(48): 13183-7, 2014 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-25287684

RESUMEN

Because of the frequent occurrence of cyclopentane subunits in bioactive compounds, the development of efficient catalytic asymmetric methods for their synthesis is an important objective. Introduced herein is a new family of chiral nucleophilic catalysts, biphenyl-derived phosphepines, and we apply them to an enantioselective variant of a useful [4+1] annulation. A range of one-carbon coupling partners can be employed, thereby generating cyclopentenes which bear a fully substituted stereocenter [either all-carbon or heteroatom-substituted (sulfur and phosphorus)]. Stereocenters at the other four positions of the cyclopentane ring can also be introduced with good stereoselectivity. An initial mechanistic study indicates that phosphine addition to the electrophilic four-carbon coupling partner is not the turnover-limiting step of the catalytic cycle.


Asunto(s)
Ciclopentanos/química , Fosfinas/química , Catálisis , Ciclización , Modelos Moleculares , Estereoisomerismo
6.
J Neurochem ; 122(1): 72-80, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21985339

RESUMEN

FOXP2, a forkhead box-containing transcription factor, forms homo- or hetero-dimers with FOXP family members and localizes to the nucleus, while FOXP2(R553H), which contains a mutation related to speech/language disorders, features reduced DNA binding activity and both cytoplasmic and nuclear localization. In addition to being a loss-of-function mutation, it is possible that FOXP2(R553H) also may act as a gain-of-function mutation to inhibit the functions of FOXP2 isoforms including FOXP2Ex10+ lacking forkhead domain. Foxp2(R552H) knock-in mouse pups exhibit impaired ultrasonic vocalization and poor dendritic development in Purkinje cells. However, expressions of Foxp2 isoforms in the developing Purkinje are unclear. The appearance of 'apical cytoplasmic swelling' (mitochondria-rich regions that are the source of budding processes) correlates with dendritic development of Purkinje cells. In the present study, we focused on Foxp2 isoforms localizing to the apical cytoplasmic swelling and identified two isoforms lacking forkhead domain: Foxp2Ex12+ and Foxp2Ex15. They partly localized to the membrane fraction that includes mitochondria. Foxp2Ex12+ mainly localized to the apical cytoplasmic swelling in early developing Purkinje cells at the stellate stage (P2-P4). Mitochondrial localization of Foxp2Ex12+ in Purkinje cells was confirmed by immune-electron microscopic analysis. Foxp2Ex12+ may play a role in dendritic development in Purkinje cells.


Asunto(s)
Cerebelo/citología , Cerebelo/crecimiento & desarrollo , Factores de Transcripción Forkhead/genética , Regulación del Desarrollo de la Expresión Génica/genética , Mitocondrias/metabolismo , Células de Purkinje/ultraestructura , Proteínas Represoras/genética , Factores de Edad , Animales , Animales Recién Nacidos , Arginina/genética , Calbindinas , Citocromos c/metabolismo , Citoplasma/metabolismo , Dendritas/metabolismo , Dendritas/ultraestructura , Feto , Factores de Transcripción Forkhead/clasificación , Histidina/genética , Humanos , Ratones , Ratones Transgénicos , Microscopía Inmunoelectrónica , Mutación/genética , Isoformas de Proteínas/genética , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Proteínas Represoras/clasificación , Proteína G de Unión al Calcio S100/metabolismo , Fracciones Subcelulares/metabolismo , Ultrasonido , Vocalización Animal/fisiología
7.
J Am Chem Soc ; 133(31): 12293-7, 2011 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-21766794

RESUMEN

Through the design and synthesis of a new chiral phosphepine, the first catalytic asymmetric method for the [3 + 2] cycloaddition of allenes with olefins has been developed that generates cyclopentenes that bear nitrogen-, phosphorus-, oxygen-, and sulfur-substituted quaternary stereocenters. A wide array of racemic γ-substituted allenes can be employed in this stereoconvergent process, which occurs with good enantioselectivity, diastereoselectivity, regioselectivity, and yield. Mechanistic studies, including a unique observation of a (modest) kinetic resolution of a racemic allene, are consistent with addition of the phosphepine to the allene being the turnover-limiting step of the catalytic cycle.


Asunto(s)
Ciclopentanos/síntesis química , Fosfinas/química , Catálisis , Cristalografía por Rayos X , Ciclización , Ciclopentanos/química , Modelos Moleculares , Estructura Molecular , Estereoisomerismo
8.
Chem Sci ; 2: 2196-2198, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22216403

RESUMEN

An effective phosphine-catalyzed method has been developed for the enantioselective addition of aryl thiols to the γ position of allenoates, thereby furnishing ready access to aryl alkyl sulfides in very good ee. An array of mechanistic data are consistent with addition of the chiral phosphine to the allenoate being the turnover-limiting step of the catalytic cycle. The optimized reaction conditions, as well as the mechanistic observations, differ markedly from an earlier report on asymmetric additions of alkyl thiols to allenoates, which highlights the potential for divergent behavior between alkyl and aryl thiols when serving as nucleophiles.

9.
Phys Rev Lett ; 102(18): 187201, 2009 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-19518905

RESUMEN

Controlling and designing quantum magnetic properties by an external electric field is a key challenge in modern magnetic physics. Here, from first principles, the effects of an external electric field on the magnetocrystalline anisotropy (MCA) in ferromagnetic transition-metal monolayers are demonstrated which show that the MCA in an Fe(001) monolayer [but not in Co(001) and Ni(001) monolayers] can be controlled by the electric field through a change in band structure, in which small components of the p orbitals near the Fermi level, which are coupled to the d states by the electric field, play a key role. This prediction obtained opens a way to control the MCA by the electric field and invites experiments.

10.
Ultramicroscopy ; 109(5): 395-8, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19136212

RESUMEN

We measured spin polarization of electrons field-emitted from half-metallic Co(2)MnSi thin film grown on a W(001) facet via chromium buffer layer using Mott scattering. For spontaneously magnetized samples, values of polarization at room temperature were observed in a range from 10% to 46% and the polarization direction was 110 orientation of substrate tungsten, which agreed with an easy axis of magnetization of bulky Co(2)MnSi. An enhancement of polarization was observed as a consequence of applying a magnetic field of 350G perpendicular to the emitter axis after the annealing at 800K. This result is considered to be caused by improvement in crystallinity of the evaporated film due to annealing.

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