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1.
Front Immunol ; 14: 1291186, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38058490

RESUMEN

Introduction: Hepatitis E virus (HEV) is a common cause of enterically transmitted acute hepatitis worldwide. The virus is transmitted by the fecal-oral route via the consumption of contaminated water supplies and is also a zoonotic foodborne pathogen. Swine are the main reservoir of zoonotic HEV. In humans, HEV infection is usually asymptomatic or causes acute hepatitis that is self-limited. However, fulminant hepatic failure and chronic cases of HEV infection can occur in some patients. In contrast, HEV infection in pigs remains asymptomatic, although the virus replicates efficiently, suggesting that swine are able to control the virus pathogenesis. Upon viral infection, IFN is secreted and activates cellular pathways leading to the expression of many IFN-stimulated genes (ISGs). ISGs can restrict the replication of specific viruses and establish an antiviral state within infected and neighboring cells. Methods: In this study, we used PCR arrays to determine the expression level of up to 168 ISGs and other IFN-related genes in the liver tissues of pigs infected with zoonotic HEV-3c and HEV-3f and in human bipotent liver HepaRG cells persistently infected with HEV-3f. Results and discussion: The expression of 12 and 25 ISGs was found to be up-regulated in infected swine livers and HepaRG cells, respectively. The expression of CXCL10, IFIT2, MX2, OASL and OAS2 was up-regulated in both species. Increased expression of IFI16 mRNA was also found in swine liver tissues. This study contributes to the identification of potential ISGs that could play a role in the control or persistence of HEV infection.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Humanos , Animales , Porcinos , Virus de la Hepatitis E/genética , Interferones/genética , Hepatitis E/genética , Hepatocitos
2.
Unfallchirurgie (Heidelb) ; 126(7): 552-558, 2023 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-37273116

RESUMEN

BACKGROUND: High expectations are currently attached to the application of artificial intelligence (AI) in the resuscitation room treatment of trauma patients with respect to the development of decision support systems. No data are available regarding possible starting points for AI-controlled interventions in resuscitation room treatment. OBJECTIVE: Do information request behavior and quality of communication indicate possible starting points for AI applications in the emergency room? MATERIAL AND METHODS: A 2­stage qualitative observational study: 1. Development of an observation sheet based on expert interviews that depicts the following six relevant topics: situational factors (course of accident, environment), vital parameters, treatment-specific Information (treatment carried out). trauma-specific factors (injury patterns), medication, special features of the patient (anamnesis, etc.) 2. Observational study Which topics were inquired about during emergency room treatment? Was the exchange of information complete? RESULTS: There were 40 consecutive observations in the emergency room. A total of 130 questions: 57/130 inquiries about medication/treatment-specific Information and vital parameters, 19/28 of which were inquiries about medication. Questions about injury-related parameters 31/130 with 18/31 regarding injury patterns, course of accident (8/31) and type of accident (5/31). Questions about medical or demographic background 42/130. Within this group, pre-existing illnesses (14/42) and demographic background (10/42) were the most frequently asked questions. Incomplete exchange of information was found in all six subject areas. CONCLUSION: Questioning behavior and incomplete communication indicate a cognitive overload. Assistance systems that prevent cognitive overload can maintain decision-making abilities and communication skills. Which AI methods can be used requires further research.


Asunto(s)
Inteligencia Artificial , Servicio de Urgencia en Hospital , Humanos , Comunicación , Estudios Observacionales como Asunto
3.
Brain Spine ; 2: 100859, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36248104

RESUMEN

Introduction: Traumatic Spinal Cord Injury (SCI) is one of the leading causes of disability in the world. Treatment is limited to supportive care and no curative therapy exists. Experimental research to understand the complex pathophysiology and potential mediators of spinal cord regeneration is essential to develop innovative translational therapies. A multitude of experimental imaging methods to monitor spinal cord regeneration in vivo have developed over the last years. However, little literature exists to deal with advanced imaging methods specifically available in SCI research. Research Question: This systematic literature review examines the current standards in experimental imaging in SCI allowing for in vivo imaging of spinal cord regeneration on a neuronal, vascular, and cellular basis. Material and Methods: Articles were included meeting the following criteria: experimental research, original studies, rodent subjects, and intravital imaging. Reviewed in detail are microstructural and functional Magnetic Resonance Imaging, Micro-Computed Tomography, Laser Speckle Imaging, Very High Resolution Ultrasound, and in vivo microscopy techniques. Results: Following the PRISMA guidelines for systematic reviews, 689 articles were identified for review, of which 492 were sorted out after screening and an additional 104 after detailed review. For qualitative synthesis 93 articles were included in this publication. Discussion and Conclusion: With this study we give an up-to-date overview about modern experimental imaging techniques with the potential to advance the knowledge on spinal cord regeneration following SCI. A thorough knowledge of the strengths and limitations of the reviewed techniques will help to optimally exploit our current experimental armamentarium in the field.

4.
EMBO J ; 41(12): e108306, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35506364

RESUMEN

Influenza virus infection causes considerable morbidity and mortality, but current therapies have limited efficacy. We hypothesized that investigating the metabolic signaling during infection may help to design innovative antiviral approaches. Using bronchoalveolar lavages of infected mice, we here demonstrate that influenza virus induces a major reprogramming of lung metabolism. We focused on mitochondria-derived succinate that accumulated both in the respiratory fluids of virus-challenged mice and of patients with influenza pneumonia. Notably, succinate displays a potent antiviral activity in vitro as it inhibits the multiplication of influenza A/H1N1 and A/H3N2 strains and strongly decreases virus-triggered metabolic perturbations and inflammatory responses. Moreover, mice receiving succinate intranasally showed reduced viral loads in lungs and increased survival compared to control animals. The antiviral mechanism involves a succinate-dependent posttranslational modification, that is, succinylation, of the viral nucleoprotein at the highly conserved K87 residue. Succinylation of viral nucleoprotein altered its electrostatic interactions with viral RNA and further impaired the trafficking of viral ribonucleoprotein complexes. The finding that succinate efficiently disrupts the influenza replication cycle opens up new avenues for improved treatment of influenza pneumonia.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Neumonía , Animales , Antivirales/farmacología , Humanos , Subtipo H3N2 del Virus de la Influenza A/metabolismo , Ratones , Proteínas de la Nucleocápside , Nucleoproteínas/metabolismo , Ácido Succínico/metabolismo , Ácido Succínico/farmacología , Ácido Succínico/uso terapéutico , Replicación Viral
5.
Genes Brain Behav ; 20(5): e12712, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33150709

RESUMEN

Alzheimer's disease (AD) is characterized by cognitive disorders and alterations of behavioral traits such as anhedonia and anxiety. Contribution of nonphysiological forms of amyloid and tau peptides to the onset of neurological dysfunctions remains unclear because most preclinical models only present one of those pathological AD-related biomarkers. A more recently developed model, the TgF344-AD rat has the advantage of overexpressing amyloid and naturally developing tauopathy, thus making it close to human familial forms of AD. We showed the presence of a learning dysfunction in a reference memory test, without spatial working memory impairment but with an increase in anxiety levels and a decrease in motivation to participate in the test. In the sucrose preference test, TgF344-AD rats did not show signs of anhedonia but did not increase the volume of liquid consumed when the water was replaced by sucrose solution. These behavioral phenomena were observed at an age when tau accumulation are absent, and where amyloid deposits are predominant in the hippocampus and the entorhinal cortex. Within the hippocampus itself, amyloid accumulation is heterogenous between the subiculum, the dorsal hippocampus and the ventral hippocampus. Thus, our data demonstrated heterogeneity in the appearance of various behavioral and neurochemical markers in the TgF344-AD rat. This multivariate analysis will therefore make it possible to define the stage of the pathology, to measure its evolution and the effects of future therapeutic treatments.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Aprendizaje por Laberinto , Memoria a Corto Plazo , Enfermedad de Alzheimer/genética , Animales , Corteza Entorrinal/fisiopatología , Femenino , Hipocampo/fisiopatología , Masculino , Ratas , Ratas Endogámicas F344 , Proteínas tau/genética , Proteínas tau/metabolismo
6.
Front Plant Sci ; 11: 745, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32655589

RESUMEN

Temperature has a major impact on plant development and growth. In temperate climates, the seasonal temperature displays large variations that can affect the early stages of plant growth and development. Sessile organisms need to be capable of responding to these conditions, so that growth temperature induces morphological and physiological changes in the plant. Besides development, there are also important molecular and ultrastructural modifications allowing to cope with different temperatures. The chloroplast plays a crucial role in plant energetic metabolism and harbors the photosynthetic apparatus. The photosynthetic light reactions are at the interface between external physical conditions (light, temperature) and the cell biochemistry. Therefore, photosynthesis requires structural flexibility to be able to optimize its efficiency according to the changes of the external conditions. To investigate the effect of growth temperature on the photosynthetic apparatus, we followed the photosynthetic performances and analyzed the protein and lipid profiles of Lepidium sativum (cress) grown at three different temperatures. This revealed that plants developing at temperatures above the optimum have a lower photosynthetic efficiency. Moreover, plants grown under elevated and low temperatures showed a different galactolipid profile, especially the amount of saturated galactolipids decreased at low temperature and increased at high temperature. From the analysis of the chlorophyll a fluorescence induction, we assessed the impact of growth temperature on the re-oxidation of plastoquinone, which is the lipidic electron carrier of the photosynthetic electron transport chain. We show that, at low temperature, along with an increase of unsaturated structural lipids and plastochromanol, there is an increase of the plastoquinone oxidation rate in the dark. These results emphasize the importance of the thylakoid membrane composition in preserving the photosynthetic apparatus under non-optimal temperatures.

7.
Cell ; 181(7): 1502-1517.e23, 2020 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-32559462

RESUMEN

RNA viruses are a major human health threat. The life cycles of many highly pathogenic RNA viruses like influenza A virus (IAV) and Lassa virus depends on host mRNA, because viral polymerases cleave 5'-m7G-capped host transcripts to prime viral mRNA synthesis ("cap-snatching"). We hypothesized that start codons within cap-snatched host transcripts could generate chimeric human-viral mRNAs with coding potential. We report the existence of this mechanism of gene origination, which we named "start-snatching." Depending on the reading frame, start-snatching allows the translation of host and viral "untranslated regions" (UTRs) to create N-terminally extended viral proteins or entirely novel polypeptides by genetic overprinting. We show that both types of chimeric proteins are made in IAV-infected cells, generate T cell responses, and contribute to virulence. Our results indicate that during infection with IAV, and likely a multitude of other human, animal and plant viruses, a host-dependent mechanism allows the genesis of hybrid genes.


Asunto(s)
Caperuzas de ARN/genética , Infecciones por Virus ARN/genética , Proteínas Recombinantes de Fusión/genética , Regiones no Traducidas 5'/genética , Animales , Bovinos , Línea Celular , Cricetinae , Perros , Humanos , Virus de la Influenza A/metabolismo , Ratones , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/metabolismo , Sistemas de Lectura Abierta/genética , Caperuzas de ARN/metabolismo , Infecciones por Virus ARN/metabolismo , Virus ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Viral/metabolismo , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Transcripción Genética/genética , Proteínas Virales/metabolismo , Replicación Viral/genética
8.
Complement Ther Med ; 48: 102221, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31987239

RESUMEN

BACKGROUND: Persons with Parkinson's disease (PD) experience somatic and psycho-emotional limitations. As a neurodegenerative disease with increasing motor symptoms, PD changes the body experience. Embodied activities like dancing are beneficial to individuals with PD regarding mobility, balance and body feeling. The objective of this study was to assess the impact of Tango Argentino (TA) on body experience in individuals with PD. METHODS: This qualitative study was conducted among 12 individuals with PD and their dance partners participating in TA courses for persons with PD and uses semi-standardized interviews. The heterogeneity of the sample was mainly based on the number of TA classes, so that participants were distinguished in participants with 10 h (beginners) and participants with more than 10 h (advanced). Further variance was due to different age groups and duration of disease. RESULTS: Participants reported change on five categories of body experiences: body awareness, motor symptoms and movement, general feelings, body sensations and disease-related feelings. Participants cited a shift in body awareness and improved stability, walking safety, enhanced mobility and amelioration in gestures and facial expressions. In general, participants described reduced body fatigue, anxiety, shame and frustration and increase in joy, pride, curiosity as well as reinforcement of partnership. With regard to perception, positive and negative feelings, ease, relaxation and increase of inner congruence were reported. The experience of normality and health helped to generate greater acceptance of disease burdens and to develop self-confidence and self-assurance. Dance partners confirmed the perceptions of the dancers with PD. CONCLUSION: The perceived effects of TA courses may be linked to a positive body awareness and body control which may be related improved motor symptoms, social and everyday life. These perceived effects should be controlled in relation to the long time change in embodied activity and body experience in persons with PD.


Asunto(s)
Danzaterapia/métodos , Movimiento , Enfermedad de Parkinson/psicología , Enfermedad de Parkinson/rehabilitación , Adulto , Anciano , Anciano de 80 o más Años , Emociones , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
Phys Chem Chem Phys ; 21(18): 9002-9012, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-30839040

RESUMEN

Semiconductor nanoparticle based porous 3D assemblies are interesting materials for various applications in the fields of photovoltaics, catalysis, or optical sensing. For use as photoelectrodes in photoelectrochemical sensors they need to be characterised by a high porosity, a good photostability, and a high charge carrier mobility. Our work reports on the preparation of cryoaerogel photoelectrodes based on CdSe nanoplatelets and their photoelectrochemical characterisation by means of linear sweep voltammetry (LSV) and intensity modulated photocurrent spectroscopy (IMPS). The obtained open-pored cryoaerogel films were observed to produce much higher photocurrents than comparable drop-cast films. By means of IMPS, the performance differences could be linked to the occurrence of charge carrier movement, which could solely be proven for the cryoaerogels. In a proof-of-principle experiment, the potential of the prepared photoelectrodes for application in photoelectrochemical sensing was moreover demonstrated.

10.
Viruses ; 10(12)2018 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-30567349

RESUMEN

Hepatitis E virus (HEV) is responsible for large waterborne epidemics of hepatitis in endemic countries and is an emerging zoonotic pathogen worldwide. In endemic regions, HEV-1 or HEV-2 genotypes are frequently associated with fulminant hepatitis in pregnant women, while with zoonotic HEV (HEV-3 and HEV-4), chronic cases of hepatitis and severe neurological disorders are reported. Hence, it is important to characterize the interactions between HEV and its host. Here, we investigated the ability of the nonstructural polyprotein encoded by the first open reading frame (ORF1) of HEV to modulate the host early antiviral response and, in particular, the type I interferon (IFN-I) system. We found that the amino-terminal region of HEV-3 ORF1 (MetYPCP), containing a putative methyltransferase (Met) and a papain-like cysteine protease (PCP) functional domain, inhibited IFN-stimulated response element (ISRE) promoter activation and the expression of several IFN-stimulated genes (ISGs) in response to IFN-I. We showed that the MetYPCP domain interfered with the Janus kinase (JAK)/signal transducer and activator of the transcription protein (STAT) signalling pathway by inhibiting STAT1 nuclear translocation and phosphorylation after IFN-I treatment. In contrast, MetYPCP had no effect on STAT2 phosphorylation and a limited impact on the activation of the JAK/STAT pathway after IFN-II stimulation. This inhibitory function seemed to be genotype-dependent, as MetYPCP from HEV-1 had no significant effect on the JAK/STAT pathway. Overall, this study provides evidence that the predicted MetYPCP domain of HEV ORF1 antagonises STAT1 activation to modulate the IFN response.


Asunto(s)
Proteasas de Cisteína/genética , Virus de la Hepatitis E/genética , Interferón Tipo I/inmunología , Metiltransferasas/genética , Sistemas de Lectura Abierta/genética , Células HEK293 , Virus de la Hepatitis E/efectos de los fármacos , Humanos , Inmunidad Innata , Interferón Tipo I/farmacología , Janus Quinasa 1/genética , Fosforilación , Factores de Transcripción STAT/genética , Transducción de Señal , Translocación Genética
11.
Int J Mol Sci ; 18(8)2017 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-28749409

RESUMEN

Highly pathogenic influenza A viruses (IAV) infections represent a serious threat to humans due to their considerable morbidity and mortality capacities. A good understanding of the molecular mechanisms responsible for the acute lung injury observed during this kind of infection is essential to design adapted therapies. In the current study, using an unbiased transcriptomic approach, we compared the host-responses of mice infected with two different subtypes of IAV: H1N1 vs. H5N1. The host-response comparison demonstrated a clear difference between the transcriptomic profiles of H1N1- and H5N1-infected mice despite identical survival kinetics and similar viral replications. The ontological analysis of the two transcriptomes showed two probable causes of death: induction of an immunopathological state of the lung for the H1N1 strain vs. development of respiratory dysfunction in the case of the H5N1 IAV. Finally, a clear signature responsible for lung edema was specifically associated with the H5N1 infection. We propose a potential mechanism of edema development based on predictive bioinformatics tools.


Asunto(s)
Interacciones Huésped-Patógeno , Subtipo H1N1 del Virus de la Influenza A/fisiología , Subtipo H5N1 del Virus de la Influenza A/fisiología , Infecciones por Orthomyxoviridae/patología , Infecciones por Orthomyxoviridae/virología , Animales , Análisis por Conglomerados , Epistasis Genética , Femenino , Perfilación de la Expresión Génica , Ontología de Genes , Interleucina-6/genética , Interleucina-6/metabolismo , Pulmón/metabolismo , Pulmón/patología , Ratones Endogámicos C57BL , Modelos Biológicos , Infecciones por Orthomyxoviridae/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Análisis de Supervivencia , Carga Viral
12.
J Gen Virol ; 98(6): 1196-1208, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28613140

RESUMEN

PB1-F2 is a viral protein encoded by influenza A viruses (IAVs). PB1-F2 is implicated in virulence by triggering immune cell apoptosis and enhancing inflammation. To obtain an insight into the molecular mechanisms of PB1-F2-mediated virulence, we used the yeast two-hybrid approach to find new PB1-F2 cellular interactors. This allowed us to identify calcium-binding and coiled-coil domain 2 (CALCOCO2, also known as NDP52) as a binding partner of PB1-F2. Binding of PB1-F2 to CALCOCO2 was confirmed by pull-down. Surface plasmon resonance binding experiments enabled us to estimate the dissociation constant (Kd) of the two partners to be around 20 nM. Using bioinformatics tools, we designed a CALCOCO2 interaction map based on previous knowledge and showed a strong connection between this protein and the type I interferon production pathways and the I-κB kinase/NF-κB signalling pathway. NF-κB reporter assays in which CALCOCO2, MAVS and PB1-F2 were co-expressed showed a cooperation of these three proteins to increase the inflammatory response. By contrast, PB1-F2 inhibits the TBK1-dependent activation of an ISRE reporter plasmid. We also demonstrated that the signal transducer TRAF6 is implicated in the enhancement of NF-κB activity mediated by PB1-F2/CALCOCO2 binding. Altogether, this report provides evidence of an interaction link between PB1-F2 and human proteins, and allows a better understanding of the involvement of PB1-F2 in the pathologic process mediated by IAV.


Asunto(s)
Interacciones Huésped-Patógeno , Inmunidad Innata , Virus de la Influenza A/inmunología , Virus de la Influenza A/patogenicidad , Proteínas Nucleares/metabolismo , Proteínas Virales/metabolismo , Factores de Virulencia/metabolismo , Biología Computacional , Humanos , Cinética , Unión Proteica , Mapeo de Interacción de Proteínas , Resonancia por Plasmón de Superficie , Técnicas del Sistema de Dos Híbridos
13.
PLoS One ; 12(4): e0176355, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28441462

RESUMEN

Avian Influenza virus (AIV) is a major concern for the global poultry industry. Since 2012, several countries have reported AIV outbreaks among domestic poultry. These outbreaks had tremendous impact on poultry production and socio-economic repercussion on farmers. In addition, the constant emergence of highly pathogenic AIV also poses a significant risk to human health. In this study, we used a chicken lung epithelial cell line (CLEC213) to gain a better understanding of the molecular consequences of low pathogenic AIV infection in their natural host. Using a transcriptome profiling approach based on microarrays, we identified a cluster of mitochondrial genes highly induced during the infection. Interestingly, most of the regulated genes are encoded by the mitochondrial genome and are involved in the oxidative phosphorylation metabolic pathway. The biological consequences of this transcriptomic induction result in a 2.5- to 4-fold increase of the ATP concentration within the infected cells. PB1-F2, a viral protein that targets the mitochondria was not found associated to the boost of activity of the respiratory chain. We next explored the possibility that ATP may act as a host-derived danger signal (through production of extracellular ATP) or as a boost to increase AIV replication. We observed that, despite the activation of the P2X7 purinergic receptor pathway, a 1mM ATP addition in the cell culture medium had no effect on the virus replication in our epithelial cell model. Finally, we found that oligomycin, a drug that inhibits the oxidative phosphorylation process, drastically reduced the AIV replication in CLEC213 cells, without apparent cellular toxicity. Collectively, our results suggest that AIV is able to boost the metabolic capacities of its avian host in order to provide the important energy needs required to produce progeny virus.


Asunto(s)
Transporte de Electrón/genética , Células Epiteliales/virología , Gripe Aviar/metabolismo , Pulmón/virología , Mitocondrias/metabolismo , Animales , Línea Celular , Pollos , Transporte de Electrón/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Perfilación de la Expresión Génica , Virus de la Influenza A , Gripe Aviar/virología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Mitocondrias/genética , Oligomicinas/farmacología , Fosforilación Oxidativa/efectos de los fármacos , Transcriptoma , Replicación Viral/efectos de los fármacos
14.
J Virol ; 90(7): 3684-93, 2016 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-26792748

RESUMEN

UNLABELLED: The influenza virus RNA-dependent RNA polymerase, which is composed of three subunits, PB1, PB2, and PA, catalyzes genome replication and transcription within the cell nucleus. The PA linker (residues 197 to 256) can be altered by nucleotide substitutions to engineer temperature-sensitive (ts), attenuated mutants that display a defect in the transport of the PA-PB1 complex to the nucleus at a restrictive temperature. In this study, we investigated the ability of the PA linker to tolerate deletion mutations for further in vitro and in vivo characterization. Four viable mutants with single-codon deletions were generated; all of them exhibited a ts phenotype that was associated with the reduced efficiency of replication/transcription of a pseudoviral reporter RNA in a minireplicon assay. Using fluorescently tagged PB1, we observed that the deletion mutants did not efficiently recruit PB1 to reach the nucleus at a restrictive temperature (39.5°C). Mouse infections showed that the four mutants were attenuated and induced antibodies that were able to protect mice from challenge with a lethal homologous wild-type virus. Serial in vitro passages of two deletion mutants at 39.5°C and 37°C did not allow the restoration of a wild-type phenotype among virus progeny. Thus, our results identify codons that can be deleted in the PA gene to engineer genetically stable ts mutants that could be used to design novel attenuated vaccines. IMPORTANCE: In order to generate genetically stable live influenza A virus vaccines, we constructed viruses with single-codon deletions in a discrete domain of the RNA polymerase PA gene. The four rescued viruses exhibited a temperature-sensitive phenotype that we found was associated with a defect in the transport of the PA-PB1 dimer to the nucleus, where viral replication occurs. These ts deletion mutants were shown to be attenuated and to be able to produce antibodies in mice and to protect them from a lethal challenge. Assays to select revertants that were able to grow efficiently at a restrictive temperature failed, showing that these deletion mutants are genetically more stable than conventional substitution mutants. These results are of interest for the design of genetically stable live influenza virus vaccines.


Asunto(s)
Codón , Virus de la Influenza A/fisiología , Proteínas Mutantes/metabolismo , ARN Polimerasa Dependiente del ARN/metabolismo , Eliminación de Secuencia , Proteínas Virales/metabolismo , Replicación Viral , Animales , Anticuerpos Antivirales/sangre , Modelos Animales de Enfermedad , Femenino , Inestabilidad Genómica , Virus de la Influenza A/genética , Virus de la Influenza A/inmunología , Ratones Endogámicos BALB C , Viabilidad Microbiana , Proteínas Mutantes/genética , Infecciones por Orthomyxoviridae/virología , ARN Polimerasa Dependiente del ARN/genética , Temperatura , Vacunas Atenuadas/genética , Vacunas Atenuadas/inmunología , Proteínas Virales/genética
15.
Brain Res ; 1567: 42-56, 2014 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-24746497

RESUMEN

Speech-associated gesturing leads to memory advantages for spoken sentences. However, unexpected or surprising events are also likely to be remembered. With this study we test the hypothesis that different neural mechanisms (semantic elaboration and surprise) lead to memory advantages for iconic and unrelated gestures. During fMRI-data acquisition participants were presented with video clips of an actor verbalising concrete sentences accompanied by iconic gestures (IG; e.g., circular gesture; sentence: "The man is sitting at the round table"), unrelated free gestures (FG; e.g., unrelated up down movements; same sentence) and no gestures (NG; same sentence). After scanning, recognition performance for the three conditions was tested. Videos were evaluated regarding semantic relation and surprise by a different group of participants. The semantic relationship between speech and gesture was rated higher for IG (IG>FG), whereas surprise was rated higher for FG (FG>IG). Activation of the hippocampus correlated with subsequent memory performance of both gesture conditions (IG+FG>NG). For the IG condition we found activation in the left temporal pole and middle cingulate cortex (MCC; IG>FG). In contrast, for the FG condition posterior thalamic structures (FG>IG) as well as anterior and posterior cingulate cortices were activated (FG>NG). Our behavioral and fMRI-data suggest different mechanisms for processing related and unrelated co-verbal gestures, both of them leading to enhanced memory performance. Whereas activation in MCC and left temporal pole for iconic co-verbal gestures may reflect semantic memory processes, memory enhancement for unrelated gestures relies on the surprise response, mediated by anterior/posterior cingulate cortex and thalamico-hippocampal structures.


Asunto(s)
Encéfalo/fisiología , Gestos , Reconocimiento en Psicología/fisiología , Semántica , Percepción del Habla/fisiología , Percepción Visual/fisiología , Adulto , Anticipación Psicológica/fisiología , Mapeo Encefálico , Discriminación en Psicología/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiología , Pruebas Neuropsicológicas , Adulto Joven
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