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1.
Heliyon ; 10(5): e25909, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38439839

RESUMEN

Objective: To investigate the stability of Acorus tatarinowii and Atractylodes lancea essential oils (ATaAL-EO) under a hot environment at 60 °C, and to analyze the differences in component, quantity, and quality changes, as well as variations in the main components, under different treatment methods of crude oil, ß-cyclodextrin inclusion of ATaAL-EO, and Pickering emulsion, to improve the stability and quality of ATaAL-EO. Methods: The stability of the ATaAL-EO group, the ß-cyclodextrin inclusion ATaAL-EO group, and the Pickering emulsion group were investigated under a 60 °C heat environment. Volatile oil retention rate and peroxide value were collected and measured. The volatile oil components of each group were determined by GC-MS, and t-tests were used to screen for differential components. PCA plots for each group were constructed using the OmicShare online platform. Line plots were generated using the Rmisc and reshape2 packages. Upset Venn diagrams under different hot environments were created using the OmicShare online platform to identify quantitative and qualitative changing components and heat map stack plots for newly generated compounds and connected line plots for disappearing compounds were produced for each group. Boxplots for the main component compounds under different hot environments were generated using the reshape2 and ggplot2 packages. Results: In a hot environment of 60 °C, the ß-cyclodextrin inclusion ATaAL-EO and Pickering emulsion group with 1, 3, and 8 h of placement showed higher retention and lower oxidation degree compared to the stability of the ATaAL-EO group. GC-MS analysis results showed that the stability of volatile components in the Pickering emulsion group and ß-cyclodextrin inclusion ATaAL-EO group was significantly improved compared to the crude oil group. Conclusion: ß-cyclodextrin inclusion complexes with ATaAL-EO, as well as Pickering emulsions, can significantly enhance the stability and quality of ATaAL-EO. Pickering emulsions have more advantages.

2.
Sci Rep ; 13(1): 19210, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37932360

RESUMEN

The Herpes simplex virus (HSV)-based platform for production of recombinant adeno-associated viral vectors (rAAVs) yields higher titers and increased percentage of full capsids when compared to the triple transient transfection (TTT) method. However, this platform currently faces two major challenges. The first challenge is the reliance on commercial media, sometimes supplemented with serum, leading to costly manufacturing and a high risk for introduction of adventitious agents. The second challenge is that the production of HSV-1 relies on adherent complementing Vero cells (V27), making it difficult to scale up. We engineered serum-free-adapted CHO cells expressing key HSV-1 entry receptors, HVEM and/or Nectin-1 to address the first challenge. Using high-throughput cloning methods, we successfully selected a HVEM receptor-expressing clone (CHO-HV-C1) that yields 1.62 × 109, 2.51 × 109, and 4.07 × 109 viral genome copies/mL with rAAV6.2-GFP, rAAV8-GFP, and rAAV9-GFP vectors respectively, within 24 h post rHSV-1 co-infection. Moreover, CHO-HV-C1-derived rAAVs had comparable in vitro transduction, infectivity, and biodistribution titers to those produced by TTT. The second challenge was addressed via engineering CHO-HV-C1 cells to express HSV-1 CP27. These cells successfully produced rHSV-1 vectors, but with significantly lower titers than V27 cells. Taken together, the CHO/HSV system provides a novel, scalable, reduced cost, serum-free AAV manufacturing platform.


Asunto(s)
Herpesvirus Humano 1 , Cricetinae , Animales , Chlorocebus aethiops , Células CHO , Cricetulus , Células Vero , Distribución Tisular , Herpesvirus Humano 1/genética , Terapia Genética
3.
Artículo en Inglés | MEDLINE | ID: mdl-37027590

RESUMEN

In this article, we present a collaborative neurodynamic optimization approach to distributed chiller loading in the presence of nonconvex power consumption functions and binary variables associated with cardinality constraints. We formulate a cardinality-constrained distributed optimization problem with nonconvex objective functions and discrete feasible regions, based on an augmented Lagrangian function. To overcome the difficulty caused by the nonconvexity in the formulated distributed optimization problem, we develop a collaborative neurodynamic optimization method based on multiple coupled recurrent neural networks reinitialized repeatedly using a meta-heuristic rule. We elaborate on experimental results based on two multi-chiller systems with the parameters from the chiller manufacturers to demonstrate the efficacy of the proposed approach in comparison to several baselines.

4.
Methods Mol Biol ; 2653: 129-149, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36995624

RESUMEN

In an era of cost-efficient gene synthesis and high-throughput construct assembly, the onus of scientific experimentation is on the rate of in vivo testing for the identification of top performing candidates or designs. Assay platforms that are relevant to the species of interest and in the tissue of choice are highly desirable. A protoplast isolation and transfection method that is compatible with a large repertoire of species and tissues would be the platform of choice. A necessary aspect of this high-throughput screening approach is the need to handle many delicate protoplast samples at the same time, which is a bottleneck for manual operation. Such bottlenecks can be mitigated with the use of automated liquid handlers for the execution of protoplast transfection steps. The method described within this chapter utilizes a 96-well head for simultaneous, high-throughput initiation of transfection. While initially developed and optimized for use with etiolated maize leaf protoplasts, the automated protocol has also been demonstrated to be compatible with other established protoplast systems, such as soybean immature embryo derived protoplast, similarly described within. This chapter also includes instructions for a sample randomization design to reduce the impact of edge effects, which might be present when microplates are used for fluorescence readout following transfection. We also describe a streamlined, expedient, and cost-effective protocol for determining gene editing efficiencies using the T7E1 endonuclease cleavage assay with a publicly available image analysis tool.


Asunto(s)
Edición Génica , Protoplastos , Protoplastos/metabolismo , Transfección , Transgenes , Hojas de la Planta/genética
5.
IEEE Trans Neural Netw Learn Syst ; 34(9): 5464-5475, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35358052

RESUMEN

This article addresses event-triggered optimal load dispatching based on collaborative neurodynamic optimization. Two cardinality-constrained global optimization problems are formulated and two event-triggering functions are defined for event-triggered load dispatching in thermal energy and electric power systems. An event-triggered dispatching method is developed in the collaborative neurodynamic optimization framework with multiple projection neural networks and a meta-heuristic updating rule. Experimental results are elaborated to demonstrate the efficacy and superiority of the approach against many existing methods for optimal load dispatching in air conditioning systems and electric power generation systems.

6.
J Environ Sci (China) ; 116: 103-113, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35219408

RESUMEN

The simultaneous electro-oxidation of Ni (II)-citrate and electrodeposition recovery of nickel metal were attempted in a combined electro-oxidation-electrodeposition reactor with a boron-doped diamond (BDD) anode and a polished titanium cathode. Effects of initial nickel citrate concentration, current density, initial pH, electrode spacing, electrolyte type, and initial electrolyte dosage on electrochemical performance were examined. The efficiencies of Ni (II)-citrate removal and nickel metal recovery were determined to be 100% and over 72%, respectively, under the optimized conditions (10 mA/cm2, pH 4.09, 80 mmol/L Na2SO4, initial Ni (II)-citrate concentration of 75 mg/L, electrode spacing of 1 cm, and 180 min of electrolysis). Energy consumption increased with increased current density, and the energy consumption was 0.032 kWh/L at a current density of 10 mA/cm2 (pH 6.58). The deposits at the cathode were characterized by scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). These characterization results indicated that the purity of metallic nickel in cathodic deposition was over 95%. The electrochemical system exhibited a prospective approach to oxidize metal complexes and recover metallic nickel.


Asunto(s)
Diamante , Contaminantes Químicos del Agua , Boro/análisis , Boro/química , Ácido Cítrico , Electrodos , Galvanoplastia , Níquel/química , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis
7.
Front Genome Ed ; 3: 670529, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34713259

RESUMEN

Recent advances in the development of CRISPR-Cas genome editing technologies have made it possible to perform targeted mutagenesis and precise gene replacement in crop plants. CRISPR-Cas9 and CRISPR-Cas12a are two main types of widely used genome editing systems. However, when CRISPR-Cas12a editing machinery is expressed from a transgene, some chromosomal targets encountered low editing frequency in important crops like maize and soybean. Here, we report efficient methods to directly generate genome edited lines by delivering Cas12a-gRNA ribonucleoprotein complex (RNP) to immature maize embryos through particle bombardment in an elite maize variety. Genome edited lines were obtained at ~7% frequency without any selection during regeneration via biolistic delivery of Cas12a RNP into immature embryos. Strikingly, the gene editing rate was increased to 60% on average and up to 100% in some experiments when the Cas12a RNP was co-delivered with a PMI selectable marker gene cassette and the induced callus cultures were selected with mannose. We also show that use of higher activity Cas12a mutants resulted in improved editing efficiency in more recalcitrant target sequence. The advances described here provide useful tools for genetic improvement of maize.

8.
Environ Pollut ; 275: 116654, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33582625

RESUMEN

Numerous genetic markers for microbial source tracking (MST) have been evaluated by testing a panel of target and nontarget faecal samples. However, the performance of MST markers may vary between faecal and water samples, thereby resulting in inaccurate water quality assessment. In this study, a 30-day sampling study was conducted in an urban river impacted by human- and sewage-associated pollution to evaluate the performance of different human-associated markers in environmental water. Additionally, marker decay was assessed via a microcosms approach. Overall, Bacteroidales 16sRNA and crAssphage markers exhibited higher prevalence in the study area, and their detection frequencies exceeded 90%. In contrast, Bacteroidales protein markers exhibited poor detection frequencies compared to other markers, with the prevalence of Hum2 and Hum163 reaching only 63% and 84%, respectively. Regarding marker abundance, there was no significant difference in the detection concentrations between Bacteroidales 16sRNA and crAssphage markers (p > 0.05); however, the concentrations of Bacteroidales protein markers were nearly 1 order of magnitude lower than those of other MST markers. The microcosm experiments indicated that the decay rate of crAssphage markers was significantly lower than that of other bacterial target markers, which may improve their detectability when the pollution source is located far from the sampling site. Due to the observed differences in performance and decay patterns among Bacteroidales 16sRNA, crAssphage, and Bacteroidales protein markers, we recommend the simultaneous use of multiple markers from different target microorganisms to obtain a more comprehensive understanding of the pollution sources. This approach would also provide an accurate assessment of pollution levels and health risks.


Asunto(s)
Microbiología del Agua , Contaminación del Agua , Monitoreo del Ambiente , Heces , Humanos , Ríos , Contaminación del Agua/análisis , Calidad del Agua
9.
Adv Mater ; 33(1): e2005074, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33241608

RESUMEN

Low-cost and large-area solar-thermal absorbers with superior spectral selectivity and excellent thermal stability are vital for efficient and large-scale solar-thermal conversion applications, such as space heating, desalination, ice mitigation, photothermal catalysis, and concentrating solar power. Few state-of-the-art selective absorbers are qualified for both low- (<200 °C) and high-temperature (>600 °C) applications due to insufficient spectral selectivity or thermal stability over a wide temperature range. Here, a high-performance plasmonic metamaterial selective absorber is developed by facile solution-based processes via assembling an ultrathin (≈120 nm) titanium nitride (TiN) nanoparticle film on a TiN mirror. Enabled by the synergetic in-plane plasmon and out-of-plane Fabry-Pérot resonances, the all-ceramic plasmonic metamaterial simultaneously achieves high, full-spectrum solar absorption (95%), low mid-IR emission (3% at 100 °C), and excellent stability over a temperature range of 100-727 °C, even outperforming most vacuum-deposited absorbers at their specific operating temperatures. The competitive performance of the solution-processed absorber is accompanied by a significant cost reduction compared with vacuum-deposited absorbers. All these merits render it a cost-effective, universal solution to offering high efficiency (89-93%) for both low- and high-temperature solar-thermal applications.

10.
Environ Pollut ; 265(Pt A): 114953, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32806427

RESUMEN

This study investigated the occurrence and distribution of pesticides in surface water (lakes, major rivers and tributaries) and potential discharge sources (fish ponds, livestock and poultry farms, and sewage treatment plants) in Wujin District (northwest of Taihu Lake), Jiangsu province, China. An analytical liquid chromatography-tandem mass spectrometry method was developed for 38 pesticides, which was applied in the monitoring of 240 surface water samples and 76 potential discharge source samples. Eleven insecticides and five fungicides with temporal and spatial variation were detected in surface water. The total pesticide concentrations in surface water in different seasons were as follows: March > August > June > November. The two most polluting and widespread pesticides were carbendazim (maximum concentration 508 ng L-1, detection rate 100%) and imidacloprid (maximum concentration 438 ng L-1, detection rate 88%). Gehu Lake (S46) and Sanshangang River (S12) were seriously polluted water bodies. Seven insecticides and four fungicides were detected in the potential discharge sources; and their composition changed significantly with the seasons. The concentrations of detected organophosphorus pesticides and neonicotinoids (e.g. acetamiprid in March and dichlorvos in November) in a few non-agricultural planting sources were far greater than those detected in surface water, and hence a few fish ponds, livestock and poultry farms, and sewage treatment plants might be the potential discharge sources of pesticides in the surrounding surface water. The estimated input flux of the studied pesticides from upstream rivers to Taihu Lake was 141.95 kg a-1. Furthermore, more attention should be paid to the medium or high aquatic ecotoxicological risk presented by the levels of organophosphorus pesticides, carbamates, and benzimidazoles.


Asunto(s)
Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Animales , China , Monitoreo del Ambiente , Lagos , Medición de Riesgo , Agua
11.
J Mol Neurosci ; 70(3): 340-352, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31776856

RESUMEN

After central nervous system (CNS) injury, a series of stress responses induce astrocytes activation. Reactive astrocytes, which are typically different from astrocytes in normal conditions in altered morphology and gene expression, combine with extracellular matrix (ECM) components to form a glial scar at the lesion site, which walls of the injured region from neighboring healthier tissue. However, as a physical and molecular barrier, glial scar can impede patients' functional recovery in the late period of CNS injury. Thus, inhibiting glial scar formation in the chronic stage after CNS injury may be a promising target to improve outcomes. Since the therapeutic strategies targeting on mediating glial scar formation are regarded as an important part on improving functional recovery after CNS injury, in this review, we focus on the regulating effects of related signaling pathways and other molecules on glial scar, and the process of glial scar formation and the roles that it plays during the acute and chronic stages are also expounded in this article. We hope to get a comprehensive understanding of glial scar during CNS injury based on current researches and to open new perspectives for the therapies to promote functional recovery after CNS injury.


Asunto(s)
Lesiones Encefálicas/metabolismo , Cicatriz/metabolismo , Neuroglía/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Animales , Lesiones Encefálicas/patología , Lesiones Encefálicas/terapia , Cicatriz/patología , Cicatriz/terapia , Humanos , Trasplante de Células Madre Mesenquimatosas/métodos , Neuroglía/patología , Transducción de Señal , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/terapia
12.
Mol Ther Methods Clin Dev ; 15: 257-263, 2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-31720304

RESUMEN

Adeno-associated virus (AAV) vectors are clinically proven gene delivery vehicles that are attracting an increasing amount of attention. Non-genome-containing empty AAV capsids are by-products during AAV production that have been reported to potentially impact AAV product safety and efficacy. Therefore, the presence and amount of empty AAV capsids need to be characterized during process development. Multiple methods have been reported to characterize empty AAV capsid levels, including transmission electron microscopy (TEM), analytical ultracentrifugation (AUC), charge detection mass spectrometry (CDMS), UV spectrophotometry, and measuring capsid and genome copies by ELISA and qPCR. However, these methods may lack adequate accuracy and precision or be challenging to transfer to a quality control (QC) lab due to the difficulty of implementation. In this study, we used AAV serotype 6.2 (AAV6.2) as an example to show the development of a QC-friendly anion exchange chromatography (AEX) assay for the determination of empty and full capsid percentages. The reported assay requires several microliters of material with a minimum titer of 5 × 1011 vg/mL, and it can detect the presence of as low as 2.9% empty capsids in AAV6.2 samples. Additionally, the method is easy to deploy, can be automated, and has been successfully implemented to support testing of various in-process and release samples.

13.
Nat Biotechnol ; 37(3): 287-292, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30833776

RESUMEN

Genome editing using CRISPR-Cas9 works efficiently in plant cells1, but delivery of genome-editing machinery into the vast majority of crop varieties is not possible using established methods2. We co-opted the aberrant reproductive process of haploid induction (HI)3-6 to induce edits in nascent seeds of diverse monocot and dicot species. Our method, named HI-Edit, enables direct genomic modification of commercial crop varieties. HI-Edit was tested in field and sweet corn using a native haploid-inducer line4 and extended to dicots using an engineered CENH3 HI system7. We also recovered edited wheat embryos using Cas9 delivered by maize pollen. Our data indicate that a transient hybrid state precedes uniparental chromosome elimination in maize HI. Edited haploid plants lack both the haploid-inducer parental DNA and the editing machinery. Therefore, edited plants could be used in trait testing and directly integrated into commercial variety development.


Asunto(s)
Sistemas CRISPR-Cas/genética , Plantas Modificadas Genéticamente/genética , Semillas/genética , Zea mays/genética , Citoplasma/genética , Edición Génica , Genoma de Planta , Haploidia , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Triticum/genética , Triticum/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo
14.
Methods Mol Biol ; 1917: 3-24, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30610624

RESUMEN

Remarkable progress in the development of technologies for sequence-specific modification of primary DNA sequences has enabled the precise engineering of crops with novel characteristics. These programmable sequence-specific modifiers include site-directed nucleases (SDNs) and base editors (BEs). Currently, these genome editing machineries can be targeted to specific chromosomal locations to induce sequence changes. However, the sequence mutation outcomes are often greatly influenced by the type of DNA damage being generated, the status of host DNA repair machinery, and the presence and structure of DNA repair donor molecule. The outcome of sequence modification from repair of DNA double-strand breaks (DSBs) is often uncontrollable, resulting in unpredictable sequence insertions or deletions of various sizes. For base editing, the precision of intended edits is much higher, but the efficiency can vary greatly depending on the type of BE used or the activity of the endogenous DNA repair systems. This article will briefly review the possible DNA repair pathways present in the plant cells commonly used for generating edited variants for genome engineering applications. We will discuss the potential use of DNA repair mechanisms for developing and improving methodologies to enhance genome engineering efficiency and to direct DNA repair processes toward the desired outcomes.


Asunto(s)
ADN de Plantas/genética , Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades/genética , Reparación del ADN por Unión de Extremidades/fisiología , Reparación del ADN/genética , Reparación del ADN/fisiología , Edición Génica , Ingeniería Genética , Genoma de Planta/genética
16.
Vaccine ; 36(14): 1871-1879, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29503113

RESUMEN

The continued detection of zoonotic influenza infections, most notably due to the avian influenza A H5N1 and H7N9 subtypes, underscores the need for pandemic preparedness. Decades of experience with live attenuated influenza vaccines (LAIVs) for the control of seasonal influenza support the safety and effectiveness of this vaccine platform. All LAIV candidates are derived from one of two licensed master donor viruses (MDVs), cold-adapted (ca) A/Ann Arbor/6/60 or ca A/Leningrad/134/17/57. A number of LAIV candidates targeting avian H5 influenza viruses derived with each MDV have been evaluated in humans, but have differed in their infectivity and immunogenicity. To understand these differences, we generated four H5N2 candidate pandemic LAIVs (pLAIVs) derived from either MDV and compared their biological characteristics in vitro and in vivo. We demonstrate that all candidate pLAIVs, regardless of gene constellation and derivation, were comparable with respect to infectivity, immunogenicity, and protection from challenge in the ferret model of influenza. These observations suggest that differences in clinical performance of H5 pLAIVs may be due to factors other than inherent biological properties of the two MDVs.


Asunto(s)
Hurones/inmunología , Inmunogenicidad Vacunal , Subtipo H5N2 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Infecciones por Orthomyxoviridae/prevención & control , Vacunas Atenuadas/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Línea Celular , Humanos , Inmunización
17.
J Virol ; 91(15)2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28490598

RESUMEN

We have developed pandemic live attenuated influenza vaccines (pLAIVs) against clade 1 H5N1 viruses on an Ann Arbor cold-adapted (ca) backbone that induced long-term immune memory. In 2015, many human infections caused by a new clade (clade 2.2.1.1) of goose/Guangdong (gs/GD) lineage H5N1 viruses were reported in Egypt, which prompted updating of the H5N1 pLAIV. We explored two strategies to generate suitable pLAIVs. The first approach was to modify the hemagglutinin gene of a highly pathogenic wild-type (wt) clade 2.2.1.1 virus, A/Egypt/N03434/2009 (Egy/09) (H5N1), with its unmodified neuraminidase (NA) gene; this virus was designated Egy/09 ca The second approach was to select a low-pathogenicity avian influenza H5 virus that elicited antibodies that cross-reacted with a broad range of H5 viruses, including the Egypt H5N1 viruses, and contained a novel NA subtype for humans. We selected the low-pathogenicity A/duck/Hokkaido/69/2000 (H5N3) (dk/Hok/00) virus for this purpose. Both candidate vaccines were attenuated and immunogenic in ferrets, inducing antibodies that neutralized homologous and heterologous H5 viruses with different degrees of cross-reactivity; Egy/09 ca vaccine antisera were more specific for the gs/GD lineage viruses but did not neutralize recent North American isolates (clade 2.3.4.4), whereas antisera from dk/Hok/69 ca-vaccinated ferrets cross-reacted with clade 2.3.4.4 and 2.2.1 viruses but not clade 1 or 2.1 viruses. When vaccinated ferrets were challenged with homologous and heterologous H5 viruses, challenge virus replication was reduced in the respiratory tract. Thus, the two H5 pLAIV candidates are suitable for clinical development to protect humans from infection with different clades of H5 viruses.IMPORTANCE In response to the continuing evolution of H5N1 avian influenza viruses and human infections, new candidate H5 live attenuated vaccines were developed by using two different approaches: one targeted a specific circulating strain in Egypt, and the other was based on a virus that elicits broadly cross-reactive antibodies against a wide range of H5 viruses. Both candidate vaccines were immunogenic and exhibited protective efficacy in ferrets. Our study permits a comparison of the two approaches, and the data support the further development of both vaccine viruses to optimally prepare for the further spread of clade 2.2.1 or 2.3.4.4 viruses.


Asunto(s)
Subtipo H5N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Reacciones Cruzadas , Modelos Animales de Enfermedad , Hurones , Genotipo , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Subtipo H5N1 del Virus de la Influenza A/clasificación , Subtipo H5N1 del Virus de la Influenza A/genética , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/genética , Vacunas contra la Influenza/aislamiento & purificación , Pruebas de Neutralización , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/prevención & control , Virus Reordenados/genética , Virus Reordenados/inmunología , Sistema Respiratorio/virología , Vacunas Atenuadas/administración & dosificación , Vacunas Atenuadas/genética , Vacunas Atenuadas/inmunología , Vacunas Atenuadas/aislamiento & purificación , Carga Viral
18.
Nature ; 542(7639): 105-109, 2017 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-28114299

RESUMEN

Sexual reproduction in flowering plants involves double fertilization, the union of two sperm from pollen with two sex cells in the female embryo sac. Modern plant breeders increasingly seek to circumvent this process to produce doubled haploid individuals, which derive from the chromosome-doubled cells of the haploid gametophyte. Doubled haploid production fixes recombinant haploid genomes in inbred lines, shaving years off the breeding process. Costly, genotype-dependent tissue culture methods are used in many crops, while seed-based in vivo doubled haploid systems are rare in nature and difficult to manage in breeding programmes. The multi-billion-dollar maize hybrid seed business, however, is supported by industrial doubled haploid pipelines using intraspecific crosses to in vivo haploid inducer males derived from Stock 6, first reported in 1959 (ref. 5), followed by colchicine treatment. Despite decades of use, the mode of action remains controversial. Here we establish, through fine mapping, genome sequencing, genetic complementation, and gene editing, that haploid induction in maize (Zea mays) is triggered by a frame-shift mutation in MATRILINEAL (MTL), a pollen-specific phospholipase, and that novel edits in MTL lead to a 6.7% haploid induction rate (the percentage of haploid progeny versus total progeny). Wild-type MTL protein localizes exclusively to sperm cytoplasm, and pollen RNA-sequence profiling identifies a suite of pollen-specific genes overexpressed during haploid induction, some of which may mediate the formation of haploid seed. These findings highlight the importance of male gamete cytoplasmic components to reproductive success and male genome transmittance. Given the conservation of MTL in the cereals, this discovery may enable development of in vivo haploid induction systems to accelerate breeding in crop plants.


Asunto(s)
Mutación del Sistema de Lectura , Haploidia , Fosfolipasas/genética , Fosfolipasas/metabolismo , Polen/enzimología , Zea mays/enzimología , Zea mays/genética , Alelos , Cruzamiento/métodos , Citoplasma/enzimología , Fertilización , Edición Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Prueba de Complementación Genética , Fenotipo , Proteínas de Plantas/metabolismo , Polen/citología , Polen/genética , Semillas/genética , Análisis de Secuencia de ARN , Zea mays/citología
19.
J Gen Virol ; 97(8): 1765-1770, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27153814

RESUMEN

Newcastle disease virus (NDV) is being developed as an oncolytic virus for virotherapy. In this study we analysed the regulation of complement-mediated inactivation of a recombinant NDV in different host cells. NDV grown in human cells was less sensitive to complement-mediated virus inactivation than NDV grown in embryonated chicken eggs. Additionally, NDV produced from HeLa-S3 cells is more resistant to complement than NDV from 293F cells, which correlated with higher expression and incorporation of complement regulatory proteins (CD46, CD55 and CD59) into virions from HeLa-S3 cells. Further analysis of the recombinant NDVs individually expressing the three CD molecules showed that CD55 is the most potent in counteracting complement-mediated virus inactivation. The results provide important information on selecting NDV manufacture substrate to mitigate complement-mediated virus inactivation.


Asunto(s)
Antígenos CD55/metabolismo , Proteínas Inactivadoras de Complemento/metabolismo , Proteínas del Sistema Complemento/metabolismo , Interacciones Huésped-Patógeno , Factores Inmunológicos/metabolismo , Virus de la Enfermedad de Newcastle/inmunología , Virus de la Enfermedad de Newcastle/fisiología , Animales , Antígenos CD59/metabolismo , Línea Celular , Pollos , Humanos , Proteína Cofactora de Membrana/metabolismo
20.
J Infect Dis ; 213(6): 922-9, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26655841

RESUMEN

BACKGROUND: We evaluated a candidate A/Anhui/2013(H7N9) pandemic live attenuated influenza vaccine (pLAIV) in healthy adults, and assessed the ability of 1 or 2 doses to induce immune memory. METHODS: Healthy subjects in 2 age groups (18-49 years and 50-70 years) with undetectable hemagglutination-inhibiting (HAI) antibody to H7N9 were enrolled. Younger subjects received either 1 or 2 intranasal doses of 10(7.0) fluorescent focus units of A/Anhui/1/2013 pLAIV, while older subjects received a single dose. All subjects received a single 30-µg dose of unadjuvanted, antigenically matched A/Shanghai2/2013(H7N9) pandemic inactivated influenza vaccine (pIIV) 12 weeks after their first dose of pLAIV. RESULTS: Both vaccines were well tolerated. Serum HAI antibody responses were detected in 0 of 32 younger subjects and 1 of 17 older subjects after 1 dose of pLAIV and in 2 of 16 younger subjects after a second dose. Strong serum antibody responses were detected after a single subsequent dose of pIIV that was broadly reactive against H7 influenza viruses. CONCLUSIONS: An A(H7N9) pLAIV candidate was safe in both age groups. Priming with pLAIV resulted in responses to subsequent pIIV that exceeded those seen in naive subjects in previous reports. The A(H7N9) pLAIV induces strong immune memory that can be demonstrated by exposure to subsequent antigenic challenge. CLINICAL TRIALS REGISTRATION: NCT01995695 and NCT02274545.


Asunto(s)
Subtipo H7N9 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/efectos adversos , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Pandemias/prevención & control , Administración Intranasal , Adolescente , Adulto , Anciano , Envejecimiento , Anticuerpos Antivirales/sangre , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Replicación Viral/fisiología , Esparcimiento de Virus , Adulto Joven
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