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1.
J Colloid Interface Sci ; 678(Pt C): 200-209, 2025 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-39293364

RESUMEN

Composite solid electrolytes (CSEs), which combine the advantages of solid polymer electrolytes and inorganic solid electrolytes, are considered to be promising electrolytes for all-solid-state lithium metal batteries. However, the current CSEs suffer from defects such as poor inorganic/organic interface compatibility, lithium dendrite growth, and easy damage of electrolyte membrane, which hinder the practical application of CSEs. Herein, a CSE (PBHL@LLZTO@DDB) with polyurethane (PBHL) as the polymer matrix and Li6.4La3Zr1.4Ta0.6O12 (LLZTO) modified by silane coupling agent (DDB) as inorganic fillers (LLZTO@DDB) has been prepared. Disulfide bond exchange reactions between PBHL and LLZTO@DDB enable PBHL@LLZTO@DDB to form a dynamic three-dimensional (3D) inorganic/organic hybrid network, which promotes the uniform dispersion of LLZTO in PBHL@LLZTO@DDB, improves the Li+ conductivity (1.24 ± 0.08 × 10-4 S cm-1 at 30 â„ƒ), and broadens the electrochemical stability window (5.16 V vs. Li+/Li). Moreover, a combination of hydrogen bonds and disulfide bonds endows PBHL@LLZTO@DDB with excellent self-healing properties. As such, both all-solid-state symmetric and full cells exhibit excellent cycle performance at ambient temperature. More importantly, the healed PBHL@LLZTO@DDB can almost completely restore its original electrochemical properties, indicating its application potential in flexible electronic products.

2.
ACS Omega ; 9(38): 39743-39756, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39346870

RESUMEN

Explosion venting is an effective method to reduce the explosion damage; in order to study the mechanism of an explosion venting process in internal and external space, this paper investigates the influence of vent parameters on hydrogen-air explosion in a rectangular duct through numerical simulation. The model including the internal and external space is first constructed, and then the explosion dynamic behaviors of the full flow field are analyzed under different vent pressures and sizes. The study aims to reveal the coupling effect of the flame, pressure, and flow field on hydrogen explosion venting. The results indicate that the explosion intensity increases with the growth of the vent pressure and the reduction of the vent size. The maximum external overpressure increases to 2.6 and 2.3 times as the vent pressure increased to 10 times or vent size reduced by 90%. The flame and combustible gas mixture evolve from a mushroom cloud into a jet form as the vent size decreases, and vortexes formed at the flame front suppress flame propagation. However, the flame speed increases significantly as the flame passes the vent under the impact of larger pressure gradient, which results in a more violent turbulence intensity and secondary external explosion.

3.
China CDC Wkly ; 5(8): 171-175, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-37008672

RESUMEN

What is already known about this topic?: Children in kindergartens and primary schools are the high-incidence groups of norovirus acute gastroenteritis. However, asymptomatic norovirus infection among them is seldom reported. What is added by this report?: The norovirus positive rate was 3.48% among asymptomatic children in kindergartens and primary schools in Beijing Municipality in June 2021, the most common genotype was GII.4 Sydney, and no acute gastroenteritis outbreak was reported over the study period. What are the implications for public health practice?: The asymptomatic norovirus infection was relatively low among kindergarten children and primary school students in summer. Norovirus genotypes in asymptomatic children were similar to those circulating in the symptomatic cases. Asymptomatic norovirus infection may play a limited role in causing acute gastroenteritis outbreaks.

4.
Int. j. morphol ; 41(1): 324-330, feb. 2023. ilus, tab, graf
Artículo en Inglés | LILACS | ID: biblio-1430512

RESUMEN

SUMMARY: The Chinese alligator (Alligator sinensis) belongs to the genus Alligator, which is a unique crocodile in China. In order to study the macroscopic structure of the heart of Chinese alligator, we performed detailed cardiac anatomy on five specimens. The heart is in the cranial mediastinum. It is caudally involved by the liver cranial margins, and ventrally by the ribs, intercostal muscles, and sternum and dorsally by the lungs. The wild Chinese alligator heart is a typical four-chamber heart, with two (right and left) atria and ventricles, left and right aorta, pulmonary artery and subclavian artery branch from the aorta. Morphology measures the circumference (129.36 mm), weight (44.14 g), and length of the heart from apex to bottom (52.50 mm). Studies have shown that the shape of the wild Chinese alligator's heart is consistent with the anatomy of other crocodiles.


El caimán chino (Alligator sinensis) pertenece al género Alligator, que es un cocodrilo único en China. Para estudiar la estructura macroscópica del corazón del caimán chino, revisamos detalladamente la anatomía cardíaca de cinco especímenes. El corazón está en el mediastino craneal. Está limitado caudalmente por los márgenes craneales del hígado, y ventralmente por las costillas, los músculos intercostales y el esternón, y dorsalmente por los pulmones. El corazón de cocodrilo chino salvaje es un corazón típico de cuatro cámaras, con dos atrios y dos ventrículos (derecho e izquierdo), aortas izquierda y derecha, arteria pulmonar y rama de la arteria subclavia de la aorta. La morfología mide la circunferencia (129,36 mm), el peso (44,14 g) y la longitud del corazón desde el ápice hasta la base (52,50 mm). Los estudios han demostrado que la forma del corazón del caimán chino salvaje es consistente con la anatomía de otros cocodrilos.


Asunto(s)
Animales , Caimanes y Cocodrilos/anatomía & histología , Corazón/anatomía & histología
5.
Front Cell Dev Biol ; 10: 821471, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35646941

RESUMEN

Intermuscular bones (IBs) are small, hard-boned spicules located in the muscle tissue that mainly exist in the myosepta of lower teleosts, which hurt the edibleness and economic value of fish. The study of the development of IBs is very important for freshwater aquaculture fish, but the molecular mechanism of its formation and the key regulatory genes remain unclear. In this study, we first constructed two types of zebrafish mutants (the mutants losing IBs and the mutants with partial deletion of IBs) by knocking out bmp6. We then carried out a transcriptomic analysis to reveal the role of bmp6 in the developmental mechanism of IBs; we used the caudal musculoskeletal tissues of these mutants and wild-type zebrafish at three development stages (20, 45, and 60 dph) to perform transcriptomic analysis. The results showed that the deficiency of bmp6 upregulated sik1 and activated the TNF-A signaling via the NF-KB pathway, which inhibited the development of osteoblasts and promoted osteoclast formation, thereby inhibiting the formation of IBs. These results provided insights to understand the role of bmp6 in the development of IBs in zebrafish and are useful for selective breeding of IBs in cyprinids.

6.
Sci Rep ; 12(1): 313, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-35013399

RESUMEN

As a powerful and attractive method for detecting gene expression, qRT-PCR has been broadly used in aquaculture research. Understanding the biology of taimen (Hucho taimen) has drawn increasing interest because of its ecological and economic value. Stable reference genes are required for the reliable quantification of gene expression, but such genes have not yet been optimized for taimen. In this study, the stability levels of 10 commonly used candidate reference genes were evaluated using geNorm, NormFinder, BestKeeper, and RefFinder. The expression levels of the 10 genes were detected using 240 samples from 48 experimental groups consisting of 40 individuals treated under four heat-stress conditions (18, 20, 22, and 24 °C) for 24 h and 26 °C for 4, 24, 48, and 72 h. Six tissues (blood, heart, brain, gill, skin, and liver) were collected from each individual. Ribosomal protein S29 (RPS29) and ribosomal protein L19 (RPL19) were the most stable genes among all of the samples, whereas 28S ribosomal RNA (28S rRNA), attachment region binding protein (ARBP), and 18S ribosomal RNA (18S rRNA) were the least stable. These results were verified by an expression analysis of taimen heat-stress genes (heat shock protein 60, hsp60, and heat shock protein 70, hsp70). In conclusion, RPS29 and RPL19 are the optimal reference genes for qRT-PCR analyses of taimen, irrespective of the tissue and experimental conditions. These results allow the reliable study of gene expression in taimen.


Asunto(s)
Chaperonina 60/genética , Proteínas de Peces/genética , Proteínas HSP70 de Choque Térmico/genética , Respuesta al Choque Térmico , Calor/efectos adversos , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Salmonidae/genética , Animales , Acuicultura , Chaperonina 60/metabolismo , Proteínas de Peces/metabolismo , Regulación de la Expresión Génica , Proteínas HSP70 de Choque Térmico/metabolismo , Estándares de Referencia , Salmonidae/metabolismo
8.
Biol Pharm Bull ; 43(4): 716-724, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32238714

RESUMEN

The purpose of this study was to investigate the preventive effect and mechanism of Dendrobium alkaloids (DNLA) on oxidative stress-related death in neuronal cells. Our results demonstrated that DNLA has a direct neuroprotective effect through oxidative stress in N2A cells induced by hydrogen peroxide (H2O2). CCK8, lactate dehydrogenase (LDH), intracellular Ca2+, intracellular reactive oxygen species (ROS), and mitochondrial membrane potential (MMP) were used to evaluate the mechanism of DNLA neutralization by H2O2-induced injury. Results presented in the paper indicate that treatment with DNLA (35 ng/mL) significantly attenuated decreases in cell viability, release of LDH, and apoptosis after H2O2-induced neuronal injury. Furthermore, DNLA significantly reduced intracellular Ca2+ up-regulation, ROS production, and inhibited mitochondrial depolarization. Moreover, DNLA treatment significantly downregulated expressions of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, IL-6, nitric oxide synthase, janus kinase-signal transducer and activators of transcription (JAK-STATs) signaling in N2A cells, all of which were H2O2-induced. Taken together, our findings suggested that DNLA may inhibit the expression of pro-inflammatory and pro-apoptotic factors by blocking JAK-STATs signaling after oxidative stress injury. This research provides a potential experimental basis for further application of DNLA to prevent various human nervous system diseases caused by oxidative stress.


Asunto(s)
Alcaloides/farmacología , Dendrobium , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Citocinas/genética , Peróxido de Hidrógeno , Janus Quinasa 1/metabolismo , Janus Quinasa 2/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Neuronas/metabolismo , Neuronas/fisiología , Óxido Nítrico Sintasa/genética , Oxidantes , Estrés Oxidativo/efectos de los fármacos , Factores de Transcripción STAT , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos
9.
Front Genet ; 10: 1202, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31850066

RESUMEN

Background: Diseases of the nervous system are widely considered to be caused by genetic mutations, and they have been shown to share pathogenic genes. Discovering the shared mechanisms of these diseases is useful for designing common treatments. Method: In this study, by reviewing 518 articles published after 2007 on 20 diseases of the nervous system, we compiled data on 1607 mutations occurring in 365 genes, totals that are 1.9 and 3.2 times larger than those collected in the Clinvar database, respectively. A combination with the Clinvar data gives 2434 pathogenic mutations and 424 genes. Using this information, we measured the genetic similarities between the diseases according to the number of genes causing two diseases simultaneously. Further detection was carried out on the similarity between diseases in terms of cell types. Disease-related cell types were defined as those with disease-related gene enrichment among the marker genes of cells, as ascertained by analyzing single-cell sequencing data. Enrichment profiles of the disease-related genes over 25 cell types were constructed. The disease similarity in terms of cell types was obtained by calculating the distances between the enrichment profiles of these genes. The same strategy was applied to measure the disease similarity in terms of brain regions by analyzing the gene expression data from 10 brain regions. Results: The disease similarity was first measured in terms of genes. The result indicated that the proportions of overlapped genes between diseases were significantly correlated to the DMN scores (phenotypic similarity), with a Pearson correlation coefficient of 0.40 and P-value = 6.0×10-3. The disease similarity analysis for cell types identified that the distances between enrichment profiles of the disease-related genes were negatively correlated to the DMN scores, with Spearman correlation coefficient = -0.26 (P-value = 1.5 × 10-2). However, the brain region enrichment profile distances of the disease-related genes were not significantly correlated with the DMN score. Besides the similarity of diseases, this study identified novel relationships between diseases and cell types. Conclusion: We manually constructed the most comprehensive dataset to date for genes with mutations related to 20 nervous system diseases. By using this dataset, the similarities between diseases in terms of genes and cell types were found to be significantly correlated to their phenotypic similarity. However, the disease similarities in terms of brain regions were not significantly correlated with the phenotypic similarities. Thus, the phenotypic similarity between the diseases is more likely to be caused by dysfunctions of the same genes or the same types of neurons rather than the same brain regions. The data are collected into the database NeurodisM, which is available at http://biomed-ai.org/neurodism.

10.
J Infect Public Health ; 12(3): 403-409, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30658905

RESUMEN

BACKGROUND: Recombinant norovirus strain GII.P7/GII.6 has been circulating in Asia and around the world for at least 20 years, but has been responsible for relatively few outbreaks. METHODS: We used statistical analyses, real-time reverse transcription - PCR, and genome sequence analyses to investigate an outbreak of gastroenteritis, identifying the pathogen, the risk factors associated with the outbreak, and the molecular features of GII.P7/GII.6 strains. RESULTS: An outbreak of gastroenteritis was reported at a school involving 12 students and lasting 6 days, from September 13 to September 18, 2017. Epidemiological studies suggested that norovirus was transmitted from person to person and not via contaminated food or drinking water in this outbreak. Using a sequence analysis of the junction region between open reading frames 1 and 2, the pathogen was identified as a recombinant norovirus (strain GII.P7/GII.6). The full-length genome of the outbreak strain shared 86%-97% identity with those of other GII.P7/GII.6 strains. Phylogenetic trees were constructed from partial open reading frame 1 (ORF1) and ORF2 sequences from the outbreak strain and GII.P7/GII.6 norovirus sequences available in GenBank. On the ORF1 tree, the partial sequences of ORF1 were grouped into cluster A (with GII.6), cluster B (with GII.7), and a separate cluster (C), based on the GII.6 and GII.7 reference strains. The ORF2 tree showed all GII.P7/GII.6 strains formed a cluster together with GII.6 strains. Amino-acid substitutions and insertions/deletions were common in the capsid protein, especially in it's P2 and P1 domains. The outbreak was controlled within several days using appropriate measures. CONCLUSIONS: Because it may play a prominent role in future outbreaks, recombinant norovirus strain GII.P7/GII.6 should be monitored with routine surveillance.


Asunto(s)
Infecciones por Caliciviridae/epidemiología , Brotes de Enfermedades , Gastroenteritis/epidemiología , Norovirus/aislamiento & purificación , Proteínas Virales/genética , Infecciones por Caliciviridae/virología , Niño , China/epidemiología , Femenino , Gastroenteritis/virología , Humanos , Masculino , Norovirus/genética , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Riesgo , Análisis de Secuencia de ADN
11.
Food Sci Biotechnol ; 27(6): 1719-1726, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30483436

RESUMEN

Fermented vegetable-fruit beverages are a popular fermented food, with many potential health benefits. In this study, two commercial Lactobacillus plantarum strains were selected to ferment a beverage containing apples, pears, and carrots. The metabolites and antioxidant activities were examined during the fermentation process. Results showed that lactic acid and acetic acid accumulated gradually, whereas malic acid decreased. Glucose and fructose increased from 0.48 and 14.8 g/L to 7.7 and 20.8 g/L, respectively, while sucrose decreased slightly. Ascorbic acid also increased continuously during the fermentation to 90.74 mg/100 mL. DPPH and ABTS radical scavenging activity and FRAP reached their maximum value after 4-8 days. The accumulation of TPC, TFC, and SOD reached their maximum value on the 8th day of fermentation. Our study revealed that the L. plantarum-fermented vegetable-fruit beverage showed significant antioxidant activity, which is helpful in evaluating the fermentation end-point and developing a high-quality fermented beverage.

12.
Anesth Analg ; 113(3): 515-22, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21680855

RESUMEN

BACKGROUND: Reliable cardiac output monitoring is particularly useful in the cirrhotic patient undergoing liver transplant surgery, because cirrhosis of the liver is associated with a vasodilated and high output state, known as cirrhotic cardiomyopathy, that challenges the reliability of pulse contour cardiac output technology. The contractility of the ventricle in cirrhosis is impaired, which is tolerated even though the ejection fraction and cardiac output are elevated because of the low peripheral resistance. However, during surgery the cirrhotic patient can decompensate because of the physiological changes and stress of surgery. Recently, we showed that the FloTrac/Vigileo™ failed to perform in cirrhotic patients undergoing transplant surgery. In response, the company upgraded their software. Therefore, we have assessed the accuracy and reliability of this new third-generation (version 3.02) FloTrac/Vigileo algorithm software in the same setting. METHODS: The cardiac index was measured simultaneously by single-bolus thermodilution (CI(TD)), using a pulmonary artery catheter, and pulse contour analysis, using the FloTrac/Vigileo (CI(V)). Readings were made at 10 time points during and after liver transplant surgery in 21 patients. Comparisons with data from our 2009 study, which used second-generation (version 01.10) software, were also made. RESULTS: Our new data show that version 3.02 software significantly reduced the adverse effect on pulse contour cardiac output reading bias in low peripheral resistance states, and thus improves the overall precision and trending ability of the system. Regression analysis between CI(TD) and CI(V) showed that the correlation was moderate (r =0.67, 95% confidence interval, 0.40 to 0.86). The Bland and Altman analysis showed that bias was 0.4 L.min(-1) · m(-2), and the percentage error was 52% (95% confidence interval, 49% to 55%). Trending ability of the new software also was improved but was still well below the current benchmarks. CONCLUSION: The new software (version 3.02) provided substantial improvements over the previous versions with better overall precision and trending ability. Further algorithm refinements will increase this technology's reliability to be extensively used in the highly complex setting of cirrhotic patients undergoing liver transplantation.


Asunto(s)
Presión Sanguínea , Gasto Cardíaco , Cardiomiopatías/fisiopatología , Cateterismo Periférico/instrumentación , Cirrosis Hepática/cirugía , Trasplante de Hígado , Monitoreo Intraoperatorio/instrumentación , Arteria Radial/fisiopatología , Programas Informáticos , Adulto , Algoritmos , Cardiomiopatías/etiología , Cateterismo de Swan-Ganz , Diseño de Equipo , Femenino , Humanos , Italia , Cirrosis Hepática/complicaciones , Cirrosis Hepática/fisiopatología , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Análisis de Regresión , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Termodilución , Factores de Tiempo
13.
Anesth Analg ; 112(1): 70-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21127281

RESUMEN

BACKGROUND: Thermodilution cardiac output using a pulmonary artery catheter is the reference method against which all new methods of cardiac output measurement are judged. However, thermodilution lacks precision and has a quoted precision error of ± 20%. There is uncertainty about its true precision and this causes difficulty when validating new cardiac output technology. Our aim in this investigation was to determine the current precision error of thermodilution measurements. METHODS: A test rig through which water circulated at different constant rates with ports to insert catheters into a flow chamber was assembled. Flow rate was measured by an externally placed transonic flowprobe and meter. The meter was calibrated by timed filling of a cylinder. Arrow and Edwards 7Fr thermodilution catheters, connected to a Siemens SC9000 cardiac output monitor, were tested. Thermodilution readings were made by injecting 5 mL of ice-cold water. Precision error was divided into random and systematic components, which were determined separately. Between-readings (random) variability was determined for each catheter by taking sets of 10 readings at different flow rates. Coefficient of variation (CV) was calculated for each set and averaged. Between-catheter systems (systematic) variability was derived by plotting calibration lines for sets of catheters. Slopes were used to estimate the systematic component. Performances of 3 cardiac output monitors were compared: Siemens SC9000, Siemens Sirecust 1261, and Philips MP50. RESULTS: Five Arrow and 5 Edwards catheters were tested using the Siemens SC9000 monitor. Flow rates between 0.7 and 7.0 L/min were studied. The CV (random error) for Arrow was 5.4% and for Edwards was 4.8%. The random precision error was ± 10.0% (95% confidence limits). CV (systematic error) was 5.8% and 6.0%, respectively. The systematic precision error was ± 11.6%. The total precision error of a single thermodilution reading was ± 15.3% and ± 13.0% for triplicate readings. Precision error increased by 45% when using the Sirecust monitor and 100% when using the Philips monitor. CONCLUSION: In vitro testing of pulmonary artery catheters enabled us to measure both the random and systematic error components of thermodilution cardiac output measurement, and thus calculate the precision error. Using the Siemens monitor, we established a precision error of ± 15.3% for single and ± 13.0% for triplicate reading, which was similar to the previous estimate of ± 20%. However, this precision error was significantly worsened by using the Sirecust and Philips monitors. Clinicians should recognize that the precision error of thermodilution cardiac output is dependent on the selection of catheter and monitor model.


Asunto(s)
Cateterismo de Swan-Ganz/instrumentación , Cateterismo de Swan-Ganz/métodos , Arteria Pulmonar , Velocidad del Flujo Sanguíneo/fisiología , Catéteres , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Arteria Pulmonar/fisiología , Distribución Aleatoria , Proyectos de Investigación , Termodilución/instrumentación , Termodilución/métodos
14.
Biomed Environ Sci ; 23(4): 259-66, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20934112

RESUMEN

OBJECTIVE: To perform gene expression profiles comparison so that to identify and understand the potential differences in pathogenesis between the pandemic and seasonal A (H1N1) influenza viruses. METHODS: A549 cells were infected with A/California/07/09 (H1N1) and A/GuangdongBaoan/51/08 (H1N1) respectively at the same MOI of 2 and collected at 2, 4, 8, and 24 h post infection (p.i.). Gene expression profiles of A549 cells were obtained using the 22 K Human Genome Oligo Array, and differentially expressed genes were analyzed at selected time points. RESULTS: Microarrays results indicated that both of the viruses suppressed host immune response related pathways including cytokine production while pandemic H1N1 virus displayed weaker suppression of host immune response than seasonal H1N1 virus. Observation on similar anti-apoptotic events such as activation of apoptosis inhibitor and down-regulation of key genes of apoptosis pathways in both infections showed that activities of promoting apoptosis were different in later stage of infection. CONCLUSIONS: The immuno-suppression and anti-apoptosis events of pandemic H1N1 virus were similar to those seen by seasonal H1N1 virus. The pandemic H1N1 virus had an ability to inhibit biological pathways associated with cytokine responses, NK activation and macrophage recognition.


Asunto(s)
Células Epiteliales/metabolismo , Perfilación de la Expresión Génica , Expresión Génica , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Gripe Humana/genética , Pandemias , Apoptosis/genética , Línea Celular Tumoral , Efecto Citopatogénico Viral , Brotes de Enfermedades , Regulación hacia Abajo , Células Epiteliales/virología , Humanos , Inmunidad Innata/genética , Subtipo H1N1 del Virus de la Influenza A/clasificación , Gripe Humana/epidemiología , Gripe Humana/inmunología , Gripe Humana/virología , Análisis de Secuencia por Matrices de Oligonucleótidos , Estaciones del Año , Regulación hacia Arriba , Virulencia
15.
J Virol ; 84(15): 7822-31, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20484512

RESUMEN

Natural killer (NK) cells are the effectors of innate immunity and are recruited into the lung 48 h after influenza virus infection. Functional NK cell activation can be triggered by the interaction between viral hemagglutinin (HA) and natural cytotoxicity receptors NKp46 and NKp44 on the cell surface. Recently, novel subtypes of influenza viruses, such as H5N1 and 2009 pandemic H1N1, transmitted directly to the human population, with unusual mortality and morbidity rates. Here, the human NK cell responses to these viruses were studied. Differential activation of heterogeneous NK cells (upregulation of CD69 and CD107a and gamma interferon [IFN-gamma] production as well as downregulation of NKp46) was observed following interactions with H5N1, 1918 H1N1, and 2009 H1N1 pseudotyped particles (pps), respectively, and the responses of the CD56(dim) subset predominated. Much stronger NK activation was triggered by H5N1 and 1918 H1N1 pps than by 2009 H1N1 pps. The interaction of pps with NK cells and subsequent internalization were mediated by NKp46 partially. The NK cell activation by pps showed a dosage-dependent manner, while an increasing viral HA titer attenuated NK activation phenotypes, cytotoxicity, and IFN-gamma production. The various host innate immune responses to different influenza virus subtypes or HA titers may be associated with disease severity.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H5N1 del Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Gripe Humana/virología , Células Asesinas Naturales/inmunología , Adulto , Antígenos CD/biosíntesis , Antígenos de Diferenciación de Linfocitos T/biosíntesis , Antígeno CD56/análisis , Citotoxicidad Inmunológica , Regulación hacia Abajo , Expresión Génica , Humanos , Interferón gamma/metabolismo , Lectinas Tipo C/biosíntesis , Subgrupos Linfocitarios/química , Subgrupos Linfocitarios/inmunología , Proteína 1 de la Membrana Asociada a los Lisosomas/biosíntesis , Receptor 1 Gatillante de la Citotoxidad Natural/biosíntesis , Regulación hacia Arriba , Adulto Joven
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