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1.
Proc Natl Acad Sci U S A ; 120(43): e2219491120, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37851678

RESUMEN

In conventional superconductors, electron-phonon coupling plays a dominant role in generating superconductivity. In high-temperature cuprate superconductors, the existence of electron coupling with phonons and other boson modes and its role in producing high-temperature superconductivity remain unclear. The evidence of electron-boson coupling mainly comes from angle-resolved photoemission (ARPES) observations of [Formula: see text]70-meV nodal dispersion kink and [Formula: see text]40-meV antinodal kink. However, the reported results are sporadic and the nature of the involved bosons is still under debate. Here we report findings of ubiquitous two coexisting electron-mode couplings in cuprate superconductors. By taking ultrahigh-resolution laser-based ARPES measurements, we found that the electrons are coupled simultaneously with two sharp modes at [Formula: see text]70meV and [Formula: see text]40meV in different superconductors with different dopings, over the entire momentum space and at different temperatures above and below the superconducting transition temperature. These observations favor phonons as the origin of the modes coupled with electrons and the observed electron-mode couplings are unusual because the associated energy scales do not exhibit an obvious energy shift across the superconducting transition. We further find that the well-known "peak-dip-hump" structure, which has long been considered a hallmark of superconductivity, is also omnipresent and consists of "peak-double dip-double hump" finer structures that originate from electron coupling with two sharp modes. These results provide a unified picture for the [Formula: see text]70-meV and [Formula: see text]40-meV energy scales and their evolutions with momentum, doping and temperature. They provide key information to understand the origin of these energy scales and their role in generating anomalous normal state and high-temperature superconductivity.

2.
Plant Biotechnol J ; 22(7): 1929-1941, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38366355

RESUMEN

Plants have evolved a sophisticated immunity system for specific detection of pathogens and rapid induction of measured defences. Over- or constitutive activation of defences would negatively affect plant growth and development. Hence, the plant immune system is under tight positive and negative regulation. MAP kinase phosphatase1 (MKP1) has been identified as a negative regulator of plant immunity in model plant Arabidopsis. However, the molecular mechanisms by which MKP1 regulates immune signalling in wheat (Triticum aestivum) are poorly understood. In this study, we investigated the role of TaMKP1 in wheat defence against two devastating fungal pathogens and determined its subcellular localization. We demonstrated that knock-down of TaMKP1 by CRISPR/Cas9 in wheat resulted in enhanced resistance to rust caused by Puccinia striiformis f. sp. tritici (Pst) and powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt), indicating that TaMKP1 negatively regulates disease resistance in wheat. Unexpectedly, while Tamkp1 mutant plants showed increased resistance to the two tested fungal pathogens they also had higher yield compared with wild-type control plants without infection. Our results suggested that TaMKP1 interacts directly with dephosphorylated and activated TaMPK3/4/6, and TaMPK4 interacts directly with TaPAL. Taken together, we demonstrated TaMKP1 exert negative modulating roles in the activation of TaMPK3/4/6, which are required for MAPK-mediated defence signalling. This facilitates our understanding of the important roles of MAP kinase phosphatases and MAPK cascades in plant immunity and production, and provides germplasm resources for breeding for high resistance and high yield.


Asunto(s)
Sistemas CRISPR-Cas , Resistencia a la Enfermedad , Enfermedades de las Plantas , Inmunidad de la Planta , Triticum , Triticum/genética , Triticum/microbiología , Triticum/inmunología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Inmunidad de la Planta/genética , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ascomicetos/fisiología , Mutagénesis , Fosfatasa 1 de Especificidad Dual/genética , Fosfatasa 1 de Especificidad Dual/metabolismo , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/genética , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/metabolismo , Puccinia/fisiología , Plantas Modificadas Genéticamente
3.
Int J Colorectal Dis ; 38(1): 99, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37067609

RESUMEN

PURPOSE: Metastatic early-onset colorectal cancer (EO-CRC) is on the rise, yet there is a dearth of predictive models for this disease. Therefore, it is crucial to develop a nomogram to aid in the early detection and management of metastatic colorectal cancer in young patients. METHODS: We retrieved data from the SEER database on patients with metastatic colorectal cancer aged 50 or younger between 2010 and 2017. The data were randomly allocated in a 7:3 ratio to training and validation cohorts, and univariate and multivariate Cox regression analyses were used to identify independent prognostic factors for overall survival (OS) and cancer-specific survival (CSS) at 1, 3, and 5 years. The nomograms were developed based on these factors, and their discriminatory and calibration capabilities were validated. Using the nomogram risk scores, patients were stratified into low-risk and high-risk groups. RESULTS: The study included 2470 patients with metastatic EO-CRC. Univariate and multivariate Cox regression analysis identified 12 independent risk factors that were included in the nomogram. The training cohort had a consistency index (C-index) of 0.71, while the validation cohort had a C-index of 0.70, demonstrating good predictive accuracy. Calibration plots showed a high level of consistency between the observed and predicted values, with overlapping plots along the diagonal. The decision curve analysis (DCA) revealed that the nomogram had a high clinical application value. CONCLUSIONS: The novel nomograms were created to predict the prognosis of patients with metastatic EO-CRC, which can aid clinicians in developing more effective treatment strategies and contribute to more accurate prognostic assessments.


Asunto(s)
Neoplasias del Colon , Neoplasias del Recto , Humanos , Investigación , Nomogramas , Calibración , Programa de VERF , Pronóstico , Estadificación de Neoplasias
4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(9): 1171-1175, 2023 Sep 10.
Artículo en Zh | MEDLINE | ID: mdl-37643968

RESUMEN

OBJECTIVE: To explore the diagnosis, treatment and genetic characteristics of a neonate with severe pulmonary hypertension and respiratory failure. METHODS: Perinatal history, clinical manifestations, laboratory finding and diagnosis and treatment data of the child were collected. Whole exome sequencing was carried out for the child, and Sanger sequencing was used to verify the candidate variants. RESULTS: The female neonate has developed progressive respiratory failure and refractory pulmonary hypertension shortly after birth. Conventional treatment such as mechanical ventilation, vasoactive drugs, and inhaled nitric oxide were ineffective. She has developed sustained pulmonary hypertension after weaning from extracorporeal membrane oxygenation therapy, and had died after the treatment had ceased. Whole exome sequencing revealed that she has harbored a heterozygous de novo variant of c.682_683insGCGGCGGC (p.G234Rfs*148) of the FOXF1 gene, which was predicted as pathogenic based on guidelines from the American College of Medical Genetics and Genomics (ACMG), with evidence items of PVS1_Strong+PM2_Supporting+PS2. Based on her clinical manifestations and result of genetic testing, the child was diagnosed with alveolar capillary dysplasia with misalignment of the pulmonary veins (ACD/MPV). CONCLUSION: Discovery of the c.682_683insGCGGCGGC (p.G234 Rfs*148) variant of the FOXF1 gene has expanded the mutational spectrum of the FOXF1 gene, which has facilitated implementation of specific treatment and provided a basis for clinical diagnosis and genetic counseling.


Asunto(s)
Hipertensión Pulmonar , Síndrome de Circulación Fetal Persistente , Venas Pulmonares , Femenino , Humanos , Niño , Recién Nacido , Embarazo , Síndrome de Circulación Fetal Persistente/diagnóstico , Síndrome de Circulación Fetal Persistente/genética , Síndrome de Circulación Fetal Persistente/terapia , Factores de Transcripción Forkhead/genética
5.
Arch Microbiol ; 204(12): 689, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36326918

RESUMEN

This study aimed to evaluate the antibacterial properties of nine lactic acid bacterial strains. The agar diffusion method (Oxford cup method) was used to assess the antimicrobial activity against pathogenic bacteria in aquaculture. The results showed that all selected strains inhibited the growth of Photobacterium damsel, Vibrio alginolyticus, Listonella anguillarum, Edwardsiella ictaluri, Aeromonas hydrophila, V. arahaemolyticus, Edwardsiella tarda and V. harveyi, but did not inhibit the growth of Metschnikowia bicuspidata. Among these strains of lactic acid bacteria, r1 was selected for its obvious antibacterial activity against eight kinds of pathogenic bacteria by 96-well plate method. Its inhibitory rate reached 96%, and it could inhibit the growth of six pathogenic bacteria at 121 â„ƒ, 20 min and pH 3.5-4.0. It was identified as Lactiplantibacillus plantarum by morphological observation and 16S rRNA sequencing analysis. Because strain r1 was isolated from culture ponds and exerted strong inhibitory effects on pathogenic bacteria, it holds potential as an agent to prevent and control infectious diseases in aquaculture. This study provides a foundation for the development and utilization of probiotics in aquaculture.


Asunto(s)
Antiinfecciosos , Enfermedades de los Peces , Lactobacillales , Probióticos , Vibrio , Animales , Lactobacillales/genética , ARN Ribosómico 16S/genética , Acuicultura/métodos , Vibrio/genética , Antiinfecciosos/farmacología , Probióticos/farmacología , Antibacterianos/farmacología , Enfermedades de los Peces/microbiología
6.
Phytopathology ; 111(2): 398-407, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32720876

RESUMEN

Plant subtilases (SBTs) or subtilisin-like proteases comprise a very diverse family of serine peptidases that participates in a broad spectrum of biological functions. Despite increasing evidence for roles of SBTs in plant immunity in recent years, little is known about wheat (Triticum aestivum) SBTs (TaSBTs). Here, we identified 255 TaSBT genes from bread wheat using the latest version 2.0 of the reference genome sequence. The SBT family can be grouped into five clades, from TaSBT1 to TaSBT5, based on a phylogenetic tree constructed with deduced protein sequences. In silico protein-domain analysis revealed the existence of considerable sequence diversification of the TaSBT family which, together with the local clustered gene distribution, suggests that TaSBT genes have undergone extensive functional diversification. Among those TaSBT genes whose expression was altered by biotic factors, TaSBT1.7 was found to be induced in wheat leaves by chitin and flg22 elicitors, as well as six examined pathogens, implying a role for TaSBT1.7 in plant defense. Transient overexpression of TaSBT1.7 in Nicotiana benthamiana leaves resulted in necrotic cell death. Moreover, knocking down TaSBT1.7 in wheat using barley stripe mosaic virus-induced gene silencing compromised the hypersensitive response and resistance against Puccinia striiformis f. sp. tritici, the causal agent of wheat stripe rust. Taken together, this study defined the full complement of wheat SBT genes and provided evidence for a positive role of one particular member, TaSBT1.7, in the incompatible interaction between wheat and a stripe rust pathogen.


Asunto(s)
Basidiomycota , Triticum , Simulación por Computador , Resistencia a la Enfermedad , Humanos , Filogenia , Enfermedades de las Plantas , Triticum/genética
7.
Appl Opt ; 60(20): 5900-5905, 2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-34263811

RESUMEN

A high-power continuous-wave (CW) ultraviolet (UV) laser at 378 nm from an intracavity frequency-doubled Alexandrite laser has been demonstrated with 638 nm fiber-coupled laser diodes as the pump source. A maximum output power of 2.55 W was obtained, which is the highest power for CW frequency-doubled Alexandrite lasers, to the best of our knowledge, corresponding to the optical-to-optical conversion efficiency of 7.9% from 638 nm pump laser to 378 nm UV laser. The beam quality factors M2 were measured to be 2.19 and 2.47 in x and y directions at UV output power of 1 W, respectively.

8.
Opt Lett ; 45(16): 4389-4392, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32796965

RESUMEN

A stable, 22.9 W, 671 nm single-frequency laser using a type II noncritically phase-matched external-cavity frequency doubling is demonstrated. The output power of the fundamental laser is 32.1 W; the corresponding conversion efficiency of frequency doubling from 1342 to 671 nm is calculated to be 71.3%. The M2 factors are measured to be 1.10 and 1.08 in the x and y directions, respectively. To the best of our knowledge, 22.9 W is the highest power obtained for a 671 nm single-frequency laser.

9.
Biomed Eng Online ; 19(1): 1, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31915014

RESUMEN

BACKGROUND: The traditional navigation interface was intended only for two-dimensional observation by doctors; thus, this interface does not display the total spatial information for the lesion area. Surgical navigation systems have become essential tools that enable for doctors to accurately and safely perform complex operations. The image navigation interface is separated from the operating area, and the doctor needs to switch the field of vision between the screen and the patient's lesion area. In this paper, augmented reality (AR) technology was applied to spinal surgery to provide more intuitive information to surgeons. The accuracy of virtual and real registration was improved via research on AR technology. During the operation, the doctor could observe the AR image and the true shape of the internal spine through the skin. METHODS: To improve the accuracy of virtual and real registration, a virtual and real registration technique based on an improved identification method and robot-assisted method was proposed. The experimental method was optimized by using the improved identification method. X-ray images were used to verify the effectiveness of the puncture performed by the robot. RESULTS: The final experimental results show that the average accuracy of the virtual and real registration based on the general identification method was 9.73 ± 0.46 mm (range 8.90-10.23 mm). The average accuracy of the virtual and real registration based on the improved identification method was 3.54 ± 0.13 mm (range 3.36-3.73 mm). Compared with the virtual and real registration based on the general identification method, the accuracy was improved by approximately 65%. The highest accuracy of the virtual and real registration based on the robot-assisted method was 2.39 mm. The accuracy was improved by approximately 28.5% based on the improved identification method. CONCLUSION: The experimental results show that the two optimized methods are highly very effective. The proposed AR navigation system has high accuracy and stability. This system may have value in future spinal surgeries.


Asunto(s)
Realidad Aumentada , Cirugía Asistida por Computador/métodos , Realidad Virtual , Humanos , Robótica , Programas Informáticos , Columna Vertebral/cirugía
10.
Appl Opt ; 59(8): 2606-2609, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32225804

RESUMEN

We present a power-scalable high-power single-frequency continuous-wave 1342 nm master oscillator power amplifier (MOPA) system that consists of a polarized single-frequency 1342 nm LD seed laser, a Raman fiber preamplifier, and a three-stage ${\rm Nd}:{{\rm YVO}_4}$Nd:YVO4 power amplifier. The single-frequency output power of 30 W at 1342 nm is achieved with the beam quality factors ${{\rm M}^{2\:}} = {1}.{26}$M2=1.26, and the power stability for 1 h is better than ${\pm }\;{0}.{5}\% $±0.5%.

11.
Opt Lett ; 43(11): 2563-2566, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29856430

RESUMEN

We report a high-energy single-frequency deep-ultraviolet (DUV) solid-state laser at 167.079 nm by the eighth-harmonic generation of a diode-pumped Nd:LGGG laser. A maximum DUV laser output energy of 1.5 µJ at a 5 Hz repetition rate with a 200 µs pulse duration is achieved. The central wavelength of the DUV laser is located at 167.079 nm and can be finely tuned from 167.075 to 167.083 nm. The linewidth is estimated to be 0.025 pm. To the best of our knowledge, this is the first Letter reporting a high-energy single-frequency solid-state DUV laser below 170 nm. The successful demonstration of the high-energy single-frequency DUV laser source with the unique wavelength is useful for direct detection of a Al+27 ion via resonance fluorescence in a multi-ion optical clock.

13.
Opt Express ; 25(11): 12860-12866, 2017 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-28786638

RESUMEN

A picosecond (ps) mid-infrared (MIR) optical parametric amplifier (OPA) with LiInSe2 crystal was demonstrated for the first time. The MIR OPA was pumped by a 30 ps 1064 nm Nd:YAG laser and injected by a barium boron oxide (BBO)-based widely tunable near-infrared seed. A maximum idler pulse energy of 433 µJ at 4 µm has been obtained under a pump energy of 17 mJ, and the corresponding pulse duration was estimated to be ~13 ps. To our knowledge, this is the highest single pulse energy generated by LiInSe2 crystal. Furthermore, an idler spectrum tuning from 3.6 to 4.8 µm was investigated at fixed pump energy of 15 mJ.

14.
Wei Sheng Wu Xue Bao ; 57(2): 304-14, 2017 Feb 04.
Artículo en Zh | MEDLINE | ID: mdl-29750493

RESUMEN

Objective: In order to get excellent strains for aquiculture water purification, we screened lactic acid bacteria from the aquaculture environment and intestinal tract of shrimp. Methods: The potential water purification ability of lactic acid bacteria at normal and low temperature was evaluated in the simulated wastewater. Morphological physio-biochemical characteristics, 16S rRNA gene sequence analysis were used to identify strain r13. Single factor test and orthogonal-design experiment were applied to optimize fermentation for r13. Results: In total 136 lactic acid bacteria strains were isolated from 3 samples. The results of water purification test suggested r13 had higher removal ability of nitrite and ammonia from water. After 72 h treatment by r13, nitrite with 11.5 mg/L in the water was completely removed and ammonia degradation rate was 29.1% with 13.0 mg/L original concentration. According to morphological, physio-biochemical characteristics and 16S rRNA gene sequence analysis, r13 was identified as Lactobacillus plantarum. The optimal fermentation condition for r13 was 6.0 g/L yeast extract, 20.0 g/L glucose, 4.0 g/L sodium acetate, 2.0 g/L diammonium hydrogen citrate, 2.0 g/L monopotassium phosphate, 50 mL tomato juice, with inoculation rate 5% (V/V), at pH 6.0 and 34℃. Under this condition cultured for 72 h, the bacterial biomass reached 28.4 g/L wet weight and cell counting reached 4.4×109 CFU/mL. Conclusion: Considering high nitrite removal ability, we suggested that r13 would be promising microorganism for water purification in aquiculture.


Asunto(s)
Lactobacillus plantarum/aislamiento & purificación , Lactobacillus plantarum/metabolismo , Aguas Residuales/microbiología , Amoníaco/metabolismo , Acuicultura , Biodegradación Ambiental , Fermentación , Ácido Láctico/metabolismo , Lactobacillus plantarum/clasificación , Lactobacillus plantarum/genética , Nitritos/metabolismo , Filogenia , Aguas Residuales/análisis , Purificación del Agua
15.
Clin Lab ; 62(6): 1139-45, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27468577

RESUMEN

BACKGROUND: Recent findings have revealed that abnormal expression of microRNAs (miRNA, miR) contributes to the malignancies of various cancers. Here, we report a novel miRNA that regulates the expression of Beclin-1 in breast cancer cells. METHODS: The expression of miR-124-3p and Beclin-1 was identified in breast cancer tissues and breast cancer cell lines. To explore whether Beclin-1 was the target gene of miR-124-3p, luciferase reporter assay was applied. MIR-124-3p was overexpressed or inhibited with the corresponding mimics or inhibitors. The expression of autophagy-related proteins including Beclin-1 and LC3II were explored by western blot and quantitative real-time PCR. RESULTS: We first demonstrated that miR-124-3p was decreased in breast cancer tissues and breast cancer cells lines. Furthermore, we validated that miR-124-3p could negatively regulate the expression of Beclin-1. Increased miR-124-3p significantly decreased the expression of Beclin-1 and LC3I. Further study showed that overexpres- sion of miR-124-3p could partially reverse 4-hydroxytamoxifen (4-OHT)-induced autophagy in breast cancer cells. CONCLUSIONS: Decreased miR-124-3p expression prompted breast cancer cell progression mainly by enhancing the expression of autophagy related protein, Beclin-1.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia , Neoplasias de la Mama/metabolismo , Proteínas de la Membrana/metabolismo , MicroARNs/metabolismo , Proteínas Reguladoras de la Apoptosis/genética , Autofagia/efectos de los fármacos , Beclina-1 , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Células MCF-7 , Proteínas de la Membrana/genética , MicroARNs/genética , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Transducción de Señal , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacología , Transfección
16.
Biochem Biophys Res Commun ; 458(4): 810-5, 2015 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-25701784

RESUMEN

Enterovirus 71 (EV71) is a neurotropic virus that causes hand, foot and mouth disease (HFMD), occasionally leading to death. As a member of the RAS association domain family (RASSFs), RASSF4 plays important roles in cell death, tumor development and signal transduction. However, little is known about the relationship between RASSF4 and EV71. Our study reveals for the first time that RASSF4 promotes EV71 replication and then accelerates AKT phosphorylation inhibition in EV71-infected 293T cells, suggesting that RASSF4 may be a potential new target for designing therapeutic measures to prevent and control EV71 infection.


Asunto(s)
Enterovirus Humano A/fisiología , Enfermedad de Boca, Mano y Pie/virología , Interacciones Huésped-Patógeno , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Replicación Viral , Apoptosis , Línea Celular , Enfermedad de Boca, Mano y Pie/fisiopatología , Humanos , Fosforilación
17.
Opt Lett ; 40(5): 776-9, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25723430

RESUMEN

We demonstrate a sub-pm linewidth acousto-optic (AO) Q-switched nanosecond Nd:GYSGG ring laser at 1336.6 nm side-pumped by 808-nm quasi-continuous wave (QCW) diode lasers for the first time. With incident pulse energy of 4.23 J at 10 Hz, a maximum output macropulse energy of 36.7 mJ at 1336.6 nm with linewidth of less than 0.85 pm and a micropulse width of 300 ns was obtained at a repetition rate of 80 Hz, corresponding to an average micropulse peak power of 15.3 kW. The M² factors were measured to be 1.42 and 1.10 in x and y directions, respectively. It can be tuned from 1336.576 to 1336.652 nm with a tuning resolution of 1 pm. The 1336.632 nm can be converted to deep ultraviolet (DUV) laser at 167.079 nm through its eighth harmonics, which is very useful for the ²7Al⁺ optical frequency standard.

18.
Opt Lett ; 40(14): 3268-71, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26176446

RESUMEN

We demonstrate a ps 167.75-nm vacuum-ultraviolet (VUV) laser by cascaded second-harmonic generation (SHG). The VUV laser is produced by eighth-harmonic generation (EHG) of a mode-locked ps 1342-nm Nd:YVO4 amplifier through three stages cascaded SHG with two LiB3O5 crystals and one KBe2BO3F2 crystal, successively. The 167.75-nm laser provides up to 65-µW output power, and the corresponding photon flux and photon flux density are 5.5×10(13) s(-1) and 1.6×10(18) s(-1)·cm(-2), respectively.

19.
Virus Genes ; 50(3): 365-74, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25724176

RESUMEN

The first Enterovirus 71 (EV71) strain isolated in 1969 was classified as genotype A. It is interesting that the genotype A disappeared nearly 40 years until its re-emergence in mainland China in 2008-2010. Few studies on genetic characterization of the re-emerged genotype A viruses have been reported. In this study, a series of analyses were performed on molecular epidemiology and genome recombination of genotype A viruses in China. Phylogenetic analysis indicated that except for 17 reported genotype A strains and 3 orphan strains (C0, C3 and B5), almost all EV71 strains in mainland China were belonging to subgenotype C4 during 1987-2011. The subgenotype C4 was further divided into 3 clades C4a1, C4a2, and C4b. The genotype A viruses co-circulated with the predominant clade C4a2 and the re-emerged clade C4b both in eastern and central China in 2008-2009. Moreover, comprehensive recombination analysis showed that the genotype A viruses were "triple-recombinant" by combination of intratypic and intertypic recombination. Intertypic recombination between the oldest C4b strain (SHZH98) and Coxsackievirus A5 (CVA5) and intratypic recombination between the SHZH98 and C1 strains both with one junction in 5'-UTR were observed for some specific C4a2 strains and the re-emerged C4b strain, respectively. And intratypic recombination between the re-emerged C4b strain and the specific C4a2 strains with one junction in 5'-UTR was observed for the Chinese genotype A viruses. Taken together, these results provided potential explanations for the genesis of Chinese genotype A viruses which were significant for preventing and controlling outbreaks.


Asunto(s)
Enterovirus Humano A/clasificación , Enterovirus Humano A/genética , Variación Genética , Genotipo , Recombinación Genética , China/epidemiología , Análisis por Conglomerados , Infecciones por Enterovirus/epidemiología , Infecciones por Enterovirus/virología , Evolución Molecular , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia
20.
Appl Opt ; 54(28): 8425-8, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26479619

RESUMEN

A low-timing-jitter high-power semiconductor saturable absorber mirror mode-locked picosecond (ps) 1063 nm Nd:GdVO4 master oscillator power amplifier is presented. Using a single-pass Nd:GdVO4 amplifier, an amplified laser with 21.5 W output power and 8.3 ps pulsewidth was achieved at 250 MHz repetition rate. Employing a servo control, an average RMS timing jitter of ∼222 fs was realized. This laser can be used as a drive laser for photocathode injectors in free-electron lasers.

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