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1.
Nutrients ; 16(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38613112

RESUMO

It remains unclear how the various environmental factors are combined in practice to influence vegetable preferences in school-aged children. This study aimed to clarify the environmental factors during infancy and their association with vegetable preference in school-aged children. To find clusters of early childhood environmental factors, we conducted a factor analysis on 58 items related to early childhood environmental factors and a k-means cluster analysis using the factors obtained. The association of the extracted factors and clusters with vegetable preferences was assessed by multiple regression analysis. Twelve factors relating to vegetable eating, cooking and harvesting experience, and parental attitudes were extracted by factor analysis. Three clusters, "low awareness of experiences", "high awareness" and "low positive encouragement", were then extracted. In the multiple regression analysis, all 12 factors were found to be associated with vegetable preferences. Furthermore, it was found that the "high awareness" group had a significantly higher score for vegetable preference than the "low awareness of experiences" group (ß = 0.56, 95% CI: 0.37-0.74). Thus, the study found that environmental factors during infancy, in isolation and combination, influenced vegetable preferences in school-aged children. Assessing the combination of various environmental factors during infancy may contribute to a better understanding of future vegetable preferences.


Assuntos
Culinária , Verduras , Pré-Escolar , Criança , Lactente , Humanos , Japão , Análise por Conglomerados , Análise Fatorial
2.
Prog Rehabil Med ; 8: 20230040, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38024959

RESUMO

Background: Magnetic stimulation devices can be large because of the need for cooling systems. We developed a compact and lightweight Spinning Permanent Magnet (SPM) device that generates magnetic fields with intensities below the motor threshold. In this report, we present the case of a post-stroke patient in which an immediate reduction in spasticity of the ankle plantar flexors was achieved after SPM treatment. Case: A 37-year-old man was admitted to our hospital with a right putamen hemorrhage. The patient underwent conservative therapy and exhibited residual left hemiplegia and spasticity. Three months after stroke onset, he was able to walk with supervision while using a left ankle-foot orthosis and a T-cane. The Modified Ashworth Scale (MAS) score of the left ankle plantar flexors was 1+. The plantar flexors were stimulated by SPM treatment. The outcomes were the Hmax/Mmax of the tibial nerve (soleus muscle) and the MAS score. On the first day, SPM stimulation was applied for 30 min. On the second day, a sham stimulation of the same duration was performed. On the third day, the SPM stimulation was repeated. Hmax/Mmax decreased from 41.5% to 37.7% on the first day, and from 46.9% to 31.6% on the third day after SPM stimulation. The MAS score decreased from 1+ to 1 on both days. In contrast, after sham stimulation, Hmax/Mmax increased from 39.2% to 44.2%, whereas the MAS score remained unchanged at 1+. Discussion: Stimulation below the motor threshold using SPM treatment can effectively reduce spasticity.

3.
Clin Interv Aging ; 18: 1453-1461, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37674531

RESUMO

Purpose: Past research has shown that exposure to the image of a slim person reduces food consumption among young adults. However, it remains unknown whether this paradigm could be adapted and applied to increase food intake among older adults with dementia by exposing them to the image of a higher-weight person to mitigate weight loss and malnutrition. The present study explored whether weight-related visual cues affect the amount of food consumed by older adults with dementia. Participants and Methods: In the experiment, twenty-one elderly people with dementia living in a nursing home were visually exposed to one of four conditions (a cartoon image of a normal-weight chef, a higher-weight chef, a flower or no image) during real-life daily lunch situations over the course of four weeks, during which each condition was presented for one week. Results: Results demonstrate that participants finished their meals more frequently when they were exposed to the image of the higher-weight chef than when they were not exposed to any images. Conclusion: These results suggest that exposure to a cartoon chef character representing a stereotyped social group related to body weight activates the stereotype and increases stereotype-consistent behavior in older adults with dementia. The present findings will contribute to understanding the effect of visual information on eating behavior and to designing eating environments which facilitate sufficient nutrition intake among older adults with dementia.


Assuntos
Demência , Desnutrição , Idoso , Humanos , Sinais (Psicologia) , Ingestão de Alimentos , Comportamento Alimentar
4.
PLoS One ; 17(10): e0275093, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36215235

RESUMO

The quality of the dietary habits of older adults is important for increasing healthy life expectancy. As with other physical senses, the senses of taste and olfaction change with age. In contrast to physical sensations that can be visibly compared with those of other people, taste and olfaction are personal sensations, making it challenging to infer associated changes. This study investigated the characteristics of taste and olfaction in healthy older adults and compared them with those of young adults. In the taste assessment, threshold values were measured using the whole-mouth method with a diagnostic assay kit (Tastedisc). The olfactory assessment measured the overall identification ability using a card-type olfactory identification test kit (Open Essence). Additionally, participants' subjective health awareness was measured using a visual analog scale. The taste and olfactory assessments results showed that the older group had lower overall sensory sensitivity than the young group, and that there was no correlation between taste and olfactory sensitivity in the older group, while a trend was observed in the young group. Moreover, there was no significant difference between the two groups regarding subjective health awareness, indicating that participants in our research considered themselves healthy regardless of age. This suggests that the subjective health awareness of older people in the health promotion class is somehow independent from their sensory ability.


Assuntos
Transtornos do Olfato , Paladar , Idoso , Autoavaliação Diagnóstica , Promoção da Saúde , Humanos , Transtornos do Olfato/diagnóstico , Olfato , Adulto Jovem
5.
Multisens Res ; 35(7-8): 537-554, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35998899

RESUMO

Interaction between odor and taste information creates flavor perception. There are many possible determinants of the interaction between odor and taste, one of which may be the somatic sensations associated with breathing. We assumed that a smell stimulus accompanied by inhaling or exhaling enhances taste intensity if the order is congruent with natural drinking. To present an olfactory stimulus from the identical location during inhalation and exhalation, we blocked the gap between the tube presenting the olfactory stimulus and the nostril. Participants breathed and ingested the solution according to the instructions on the screen and evaluated the solution's taste intensity. Vanilla odor enhanced the sweet taste in both retronasal and orthonasal conditions when the order of stimuli was congruent with natural drinking, but it did not do so in either condition when they were incongruent. The results suggest that breathing is a determinant of odor-taste interaction. The methods of presenting olfactory stimuli used in this study were compared and discussed in relation to those used in previous studies. Odor-induced taste enhancement depends on the time order of smell with breathing and taste congruency in natural drinking. Taste enhancement was induced by odor in both conditions by minimizing differences in odor presentation between them.


Assuntos
Odorantes , Paladar , Humanos , Olfato , Percepção Gustatória , Respiração
6.
J Infect Dis ; 225(2): 269-281, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34223910

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging, life-threatening tick-borne viral hemorrhagic fever caused by SFTS virus (SFTSV). Transient appearance of plasmablastic lymphocytes in the peripheral blood of SFTS cases has been reported; however, the pathological significance of this transient burst in peripheral blood plasmablastic lymphocytes is unclear. Here, we show that SFTSV infection of human peripheral blood mononuclear cells in vitro induced propagation of atypical lymphocytes. These atypical lymphocytes were activated B cells, which were induced by secretory factors other than viral particles; these factors were secreted by SFTSV-infected B cells. Activated B cells shared morphological and immunophenotypic characteristics with B cells of plasmablast lineage observed in peripheral blood and autopsy tissues of SFTS cases. This suggests that SFTSV-infected B cells secrete factors that induce B-cell differentiation to plasmablasts, which may play an important role in pathogenesis of SFTS through the SFTSV-B cell axis.


Assuntos
Leucócitos Mononucleares , Phlebovirus/isolamento & purificação , Febre Grave com Síndrome de Trombocitopenia , Linfócitos B , Infecções por Bunyaviridae , Humanos
7.
Food Sci Nutr ; 9(2): 719-727, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33598157

RESUMO

Sweeteners are widely used in food products, and their sweetness potency is usually evaluated by comparing it with that of sucrose. This, however, has led to confusion as some sweeteners are evaluated based on their maximum value of sweet taste response, while others are evaluated by their threshold value. Here, we aimed to develop a novel nonverbal sweetness evaluation system through the sweet taste signal transduction by comparing the responses of the sweet taste receptor, salivation, taste intensity, and preference among six sweeteners. The hT1r2/hT1r3 sweet taste receptor responses represented the input signal of the sweet taste signal transduction, while salivation, sweet taste intensity, and participants' preferences represented the output signals by the gustatory-salivary reflex, primary gustatory cortex area, and the secondary gustatory cortex, respectively. Our results showed that the sweet taste receptor, sweet intensity, and salivary secretion responses were concentration-dependent and expressed exponentially. Moreover, the results comparing coefficients showed 15-35 times more sensitivity between the response of hT1r2/hT1r3 and the salivation or the sweet taste intensity in non-nutrient sweeteners. The preference graph curve was not exponential, suggesting that the sweetener preference was not related to the sweet taste receptor, salivation, or sweet taste intensity. These results may suggest that the sweet taste signal of the non-nutritive sweeteners might be maintained by taste reception by hT1r2/hT1r3 to taste recognition in the primary gustatory area and that receptor responses and salivation could be used as indicators of sweetness intensity.

8.
RSC Adv ; 11(33): 20529-20540, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35479917

RESUMO

Turpentine is a renewable resource, has good combustion performance, and is considered to be a fuel or promising additive to diesel fuel. This is very important for the investigation of thermal stability and energy oxidation characteristics, because evaluation of energy or fuel quality assurance and use safety are necessary. The main components of turpentine are α-pinene and ß-pinene, which have unsaturated double bonds and high chemical activity. By investigating their thermal stability and oxidation reaction characteristics, we know the chemical thermal properties and thermal explosion hazard of turpentine. In this present study, the thermal stability and oxidation characteristics of α-pinene, ß-pinene and α-pinene/ß-pinene mixture were investigated using a high sensitivity accelerating rate calorimeter (ARC) and C80 calorimeter. The important parameters of oxidation reaction and thermal stability were obtained from the temperature, pressure and exothermic behavior in chemical reaction. The results show that α-pinene and ß-pinene are thermally stable without chemical reaction under a nitrogen atmosphere even when the temperature reaches 473 K. The initial exothermic temperature of the two pinenes and their mixture is 333-338 K, and the heat release (-ΔH) of their oxidation is 2745-2973 J g-1. The oxidation activation energy (E a) of α-pinene, ß-pinene and α-pinene/ß-pinene mixture is 116.25 kJ mol-1, 121.85 kJ mol-1, and 115.95 kJ mol-1, respectively. There are three steps in the oxidation of pinenes: the first is the induction period of the oxidation reaction; the second is the main oxidation stage, and the pressure is reduced; the third is thermal decomposition to produce gas.

9.
ACS Omega ; 5(49): 31957-31962, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33344850

RESUMO

Microwaves (MWs) are often used to enhance various heterogeneous catalytic reactions. Here, we demonstrate real-time monitoring of a catalyst's oxidation state in a microwave catalytic reaction using a resonance frequency. The changes in the catalyst's oxidation state during the reaction induced changes in the resonance frequency in the cavity resonator. The resonance frequency was not affected by 2-propanol adsorption, while the frequency decreased with the reduction of WO3 → WO3-x. That is, the redox state of the WO3 catalyst could be detected using the resonance frequency. The oxidation state of the WO3 catalyst was then directly observed by the resonance frequency during the dehydration reaction of 2-propanol by microwaves as a model reaction. Resonance frequency monitoring revealed that the enhanced dehydration of 2-propanol by microwaves was attributable to the reduction of the WO3 catalyst. Moreover, the temporal changes in the oxidation state of the WO3 catalyst detected by the resonance frequency coincided with that observed by operando Raman spectroscopy. Therefore, real-time resonance frequency monitoring allowed facile detection of the bulk catalyst oxidation state under microwaves without using any spectroscopic apparatus.

10.
ACS Omega ; 5(45): 29102-29109, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33225141

RESUMO

Rosin is a sustainable resource, which is mainly composed of resin acid. Rosin-modified resin is widely used in adhesives, inks, coatings, and other fields, and its stability is very important for the production, storage, and use of products. Thermal stability and reactivity of three resin acids (levopimaric acid, neoabietic acid, and dehydroabietic acid) and four rosin-modified resins were studied using an accelerating rate calorimeter (ARC). They are stable, and exothermic reactions do not occur even when they were heated to 200 °C under a nitrogen atmosphere, but they are unstable under an oxygen atmosphere. The mechanism of the oxidation reaction process was found: first, resin acids absorb oxygen, and then an exothermic oxidation occurs. The initial exothermic temperature (T 0) of levopimaric acid, neoabietic acid, and dehydroabietic acid are 354.01, 353.83, and 398.20 K, the initial oxidation kinetics shows a second-order reaction, and the activation energies (E a) are 42.90, 58.05, and 46.60 kJ/mol, respectively. Peroxide concentration of three resin acids were determined by iodometry. The T 0 values of hydrogenated rosin, disproportionated rosin, hydrogenated rosin glyceride, and hydrogenated rosin pentaerythritol ester, the four rosin-modified resin, are 353.71, 348.32, 412.85, and 412.44 K. Levopimaric acid and neoabietic acid have higher oxidative reactivity and easily undergoes an oxidation reaction at lower temperature. Rosin-modified resins are stable and find it difficult to undergo oxidation reactions.

11.
ACS Omega ; 5(37): 23520-23523, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32984670

RESUMO

We demonstrate that the surface of an α-Al2O3(001) single crystal recrystallizes to α-AlO(OH) under ultrahigh pressure (8 GPa) at 600 °C. The recrystallization depends on the degree of surface roughness. A polished surface topotaxially recrystallizes to (100)-oriented α-AlO(OH) microcrystals, while unpolished surface recrystallizes to polycrystalline α-AlO(OH). This study demonstrates a new synthetic route to obtain oriented crystals of ultrahigh-pressure-phase materials and paves the way for the investigations of the physical and chemical properties of such materials.

12.
J Biol Chem ; 295(23): 7941-7957, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32341071

RESUMO

Chikungunya fever is a re-emerging zoonotic disease caused by chikungunya virus (CHIKV), a member of the Alphavirus genus in the Togaviridae family. Only a few studies have reported on the host factors required for intracellular CHIKV trafficking. Here, we conducted an imaging-based siRNA screen to identify human host factors for intracellular trafficking that are involved in CHIKV infection, examined their interactions with CHIKV proteins, and investigated the contributions of these proteins to CHIKV infection. The results of the siRNA screen revealed that host endosomal sorting complexes required for transport (ESCRT) proteins are recruited during CHIKV infection. Co-immunoprecipitation analyses revealed that both structural and nonstructural CHIKV proteins interact with hepatocyte growth factor-regulated tyrosine kinase substrate (HGS), a component of the ESCRT-0 complex. We also observed that HGS co-localizes with the E2 protein of CHIKV and with dsRNA, a marker of the replicated CHIKV genome. Results from gene knockdown analyses indicated that, along with other ESCRT factors, HGS facilitates both genome replication and post-translational steps during CHIKV infection. Moreover, we show that ESCRT factors are also required for infections with other alphaviruses. We conclude that during CHIKV infection, several ESCRT factors are recruited via HGS and are involved in viral genome replication and post-translational processing of viral proteins.


Assuntos
Febre de Chikungunya/metabolismo , Febre de Chikungunya/virologia , Vírus Chikungunya/crescimento & desenvolvimento , Vírus Chikungunya/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Replicação Viral , Vírus Chikungunya/genética , Células HEK293 , Humanos , Replicação Viral/genética
13.
Data Brief ; 28: 105079, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32226816

RESUMO

This data article includes the visual stimuli used to model the freshness perception of four different vegetable textures, namely a cabbage, a carrot, a strawberry and a spinach. All four vegetables were optically measured during their degradation process in a humidity, temperature and light controlled environment. The visual data is in csv format for convenient usage. Each data point represents a pixel value using the hardware independent XYZ color space. The total size of the data can be related to an equivalent image of 1360 × 1024 resolution. Additionally, using the calibration data of an LCD-Display, the respective RGB color space images were derived from the XYZ data as an example. For interpretation and discussion, please see the original article entitled "Model of vegetable freshness perception using luminance cues" [1].

14.
Sci Rep ; 10(1): 2689, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060366

RESUMO

Scandium is being explored as an alloying element for aluminium alloys, which are gaining importance as high-performance lightweight structural alloys in the transportation industry. Sc-rich ScAlN thin films show strong piezoelectricity and can be fabricated on a hard substrate for use as wideband surface acoustic wave filters in next-generation wireless mobile communication systems. However, the use of ScAlN thin films in microelectromechanical system devices is limited by the high cost of metallic Sc, which is due to the difficulty in smelting of this material. Here, we propose a novel microwave irradiation process for producing Al-Sc alloys, with Mg ions as a reducing agent. Although scandium oxide is thermodynamically stable, intermetallic Al3Sc is obtained in high yield (69.8%) via a low-temperature (660 °C) reduction reaction under microwave irradiation. Optical spectroscopy results and thermodynamic considerations suggest a non-thermal equilibrium reaction with the univalent magnesium ions excited by microwave irradiation.

15.
J Clin Invest ; 130(2): 799-812, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31904586

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging hemorrhagic fever caused by a tick-borne banyangvirus and is associated with high fatality. Despite increasing incidence of SFTS and serious public health concerns in East Asia, the pathogenesis of lethal SFTS virus (SFTSV) infection in humans is not fully understood. Numbers of postmortem examinations to determine target cells of the viral infection have so far been limited. Here we showed that B cells differentiating into plasmablasts and macrophages in secondary lymphoid organs were targets for SFTSV at the end stage of lethal infection, and the majority of SFTSV-infected cells were B cell-lineage lymphocytes. In affected individuals, B cell-lineage lymphocytes with SFTSV infection were widely distributed in both lymphoid and nonlymphoid organs, and infiltration of these cells into the capillaries of the organs could be observed occasionally. Moreover, a human plasmablastic lymphoma cell line, PBL-1, was susceptible to SFTSV propagation and had a similar immunophenotype to that of target cells of SFTSV in fatal SFTS. PBL-1 can therefore provide a potential in vitro model for human SFTSV infection. These results extend our understanding of the pathogenesis of human lethal SFTSV infection and can facilitate the development of SFTSV countermeasures.


Assuntos
Diferenciação Celular/imunologia , Febre por Flebótomos/imunologia , Phlebovirus/imunologia , Plasmócitos/imunologia , Linhagem Celular , Feminino , Humanos , Masculino , Febre por Flebótomos/mortalidade , Febre por Flebótomos/patologia , Plasmócitos/patologia
16.
Commun Chem ; 3(1): 86, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-36703448

RESUMO

Microwave irradiation can cause high local temperatures at supported metal nanoparticles, which can enhance reaction rates. Here we discuss the temperature of platinum nanoparticles on γ-Al2O3 and SiO2 supports under microwave irradiation using the Debye-Waller factor obtained from in situ extended X-ray absorption fine structure (EXAFS) measurements. Microwave irradiation exhibits considerably smaller Deby-Waller factors than conventional heating, indicating the high local temperature at the nanoparticles. The difference in the average temperatures between the platinum nanoparticles and the bulk under microwaves reaches 26 K and 132 K for Pt/Al2O3 and Pt/SiO2, respectively. As a result, Pt/SiO2 exhibits considerably more reaction acceleration for the catalytic dehydrogenation of 2-propanol under microwave irradiation than Pt/Al2O3. We also find microwaves enhance the reduction of PtOx nanoparticles by using operando X-ray absorption near edge structure (XANES) spectroscopy. The present results indicate that significant local heating of platinum nanoparticles by microwaves is effective for the acceleration of catalytic reactions.

17.
Phys Chem Chem Phys ; 22(3): 1003-1010, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31776539

RESUMO

Cellulose dissolution in mixtures of the ionic liquid 1-ethyl-3-methylimidazolium acetate with dimethylsulfoxide, [C2C1Im][OAc] + DMSO, have been kinetically compared using conventional heating and microwave heating in a single-mode cavity with a semiconductor generator. Microwaves led to enhancements in the dissolution rate between 21 and 57% under different conditions of temperature and concentration of ionic liquid. Rate enhancement by microwaves prominently occurred at temperatures above 60 °C. Based on an Arrhenius plot and wide-band dielectric measurements we advance the hypothesis that the faster dissolution is caused by ionic motion induced by microwaves in the timescale of formation and breaking of hydrogen bonds between cellulose chains and acetate anions.

18.
J Phys Chem Lett ; 10(12): 3390-3394, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31050903

RESUMO

Microwave irradiation has great potential to control chemical reactions remotely, particularly reactions that involve electron transfer. In this study, we found that the reduction reaction of bipyridine derivatives on metal nickel particles was accelerated or decelerated by 2.45 GHz microwaves without an alteration of the reaction temperature. The order of the extent of the microwave acceleration of the electron transfer reaction coincided with the negativity of the redox potential of the bipyridine derivatives, i.e., the electron transfer with smaller Δ G was significantly enhanced by microwave irradiation. By applying Marcus' electron transfer theory, we propose two mechanisms of the microwave effect on electron transfer reactions, i.e., vibration of the electrons in Ni particles to make the electron transfer easier and rotation of the water molecules to prevent the reorganization of the hydrated systems after the electron transfer reaction.

19.
Cogn Neurodyn ; 13(1): 1-11, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30728867

RESUMO

Recent advances in nonlinear analytic methods for electroencephalography have clarified the reduced complexity of spatiotemporal dynamics in brain activity observed in Alzheimer's disease (AD). However, there are far fewer studies exploring temporal scale dependent fractal properties in AD, despite the importance of studying the dynamics of brain activity within physiologically relevant frequency ranges. Higuchi's fractal dimension is a widely used index for evaluating fractality in brain activity, but temporal-scale-specific characteristics are lost due to its requirement of averaging over the entire range of temporal scales. In this study, we adapted Higuchi's fractal algorithm into a method for investigating temporal-scale-specific fractal properties. We then compared the values of the temporal-scale-specific fractal dimension between healthy control (HC) and AD patient groups. Our data indicate that relative to the HC group, the AD group demonstrated reduced fractality at both slow and fast temporal scales. Moreover, we confirmed that the fractality at fast temporal scales correlates with cognitive decline. These properties might serve as a basis for a useful approach to characterizing temporal neural dynamics in AD or other neurodegenerative disorders.

20.
PLoS Pathog ; 15(1): e1007427, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30605488

RESUMO

Mucosal immunoglobulins comprise mainly secretory IgA antibodies (SIgAs), which are the major contributor to pathogen-specific immune responses in mucosal tissues. These SIgAs are highly heterogeneous in terms of their quaternary structure. A recent report shows that the polymerization status of SIgA defines their functionality in the human upper respiratory mucosa. Higher order polymerization of SIgA (i.e., tetramers) leads to a marked increase in neutralizing activity against influenza viruses. However, the precise molecular mechanisms underlying the effects of SIgA polymerization remain elusive. Here, we developed a method for generating recombinant tetrameric monoclonal SIgAs. We then compared the anti-viral activities of these tetrameric SIgAs, which possessed variable regions identical to that of a broadly neutralizing anti-influenza antibody F045-092 against influenza A viruses, with that of monomeric IgG or IgA. The tetrameric SIgA showed anti-viral inhibitory activity superior to that of other forms only when the antibody exhibits low-affinity binding to the target. By contrast, SIgA tetramerization did not substantially modify anti-viral activity against targets with high-affinity binding. Taken together, the data suggest that tetramerization of SIgA improved target breadth, but not peak potency of antiviral functions of the broadly neutralizing anti-influenza antibody. This phenomenon presumably represents one of the mechanisms by which SIgAs present in human respiratory mucosa prevent infection by antigen-drifted influenza viruses. Understanding the mechanisms involved in cross neutralization of viruses by SIgAs might facilitate the development of vaccine strategies against viral infection of mucosal tissues.


Assuntos
Anticorpos Neutralizantes/imunologia , Imunoglobulina A Secretora/imunologia , Imunoglobulina A Secretora/metabolismo , Animais , Anticorpos Neutralizantes/fisiologia , Anticorpos Antivirais/imunologia , Antivirais , Linhagem Celular , Embrião de Galinha , Cães , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Imunoglobulina A/imunologia , Imunoglobulina A/metabolismo , Imunoglobulina A Secretora/fisiologia , Vírus da Influenza A/imunologia , Vacinas contra Influenza , Influenza Humana/imunologia , Células Madin Darby de Rim Canino , Testes de Neutralização , Orthomyxoviridae/imunologia , Polimerização , Ligação Proteica , Proteínas Recombinantes/metabolismo
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