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1.
bioRxiv ; 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37398405

RESUMO

Small RNAs (sRNAs) of the fungal pathogen Botrytis cinerea can enter plant cells and hijack host Argonaute protein 1 (AGO1) to silence host immunity genes. However, the mechanism by which these fungal sRNAs are secreted and enter host cells remains unclear. Here, we demonstrate that B. cinerea utilizes extracellular vesicles (EVs) to secrete Bc-sRNAs, which are then internalized by plant cells through clathrin-mediated endocytosis (CME). The B. cinerea tetraspanin protein, Punchless 1 (BcPLS1), serves as an EV biomarker and plays an essential role in fungal pathogenicity. We observe numerous Arabidopsis clathrin-coated vesicles (CCVs) around B. cinerea infection sites and the colocalization of B. cinerea EV marker BcPLS1 and Arabidopsis CLATHRIN LIGHT CHAIN 1, one of the core components of CCV. Meanwhile, BcPLS1 and the B. cinerea-secreted sRNAs are detected in purified CCVs after infection. Arabidopsis knockout mutants and inducible dominant-negative mutants of key components of CME pathway exhibit increased resistance to B. cinerea infection. Furthermore, Bc-sRNA loading into Arabidopsis AGO1 and host target gene suppression are attenuated in those CME mutants. Together, our results demonstrate that fungi secrete sRNAs via EVs, which then enter host plant cells mainly through CME.

2.
Nat Commun ; 14(1): 4383, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474601

RESUMO

Small RNAs (sRNAs) of the fungal pathogen Botrytis cinerea can enter plant cells and hijack host Argonaute protein 1 (AGO1) to silence host immunity genes. However, the mechanism by which these fungal sRNAs are secreted and enter host cells remains unclear. Here, we demonstrate that B. cinerea utilizes extracellular vesicles (EVs) to secrete Bc-sRNAs, which are then internalized by plant cells through clathrin-mediated endocytosis (CME). The B. cinerea tetraspanin protein, Punchless 1 (BcPLS1), serves as an EV biomarker and plays an essential role in fungal pathogenicity. We observe numerous Arabidopsis clathrin-coated vesicles (CCVs) around B. cinerea infection sites and the colocalization of B. cinerea EV marker BcPLS1 and Arabidopsis CLATHRIN LIGHT CHAIN 1, one of the core components of CCV. Meanwhile, BcPLS1 and the B. cinerea-secreted sRNAs are detected in purified CCVs after infection. Arabidopsis knockout mutants and inducible dominant-negative mutants of key components of the CME pathway exhibit increased resistance to B. cinerea infection. Furthermore, Bc-sRNA loading into Arabidopsis AGO1 and host target gene suppression are attenuated in those CME mutants. Together, our results demonstrate that fungi secrete sRNAs via EVs, which then enter host plant cells mainly through CME.


Assuntos
Arabidopsis , Vesículas Extracelulares , Arabidopsis/microbiologia , RNA Fúngico/genética , Células Vegetais , Endocitose , Clatrina , Doenças das Plantas/microbiologia
3.
Colloids Surf B Biointerfaces ; 198: 111456, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33246776

RESUMO

The tuning of surface properties through functionalization is an important field of research with a broad spectrum of applications. Self-assembled monolayers (SAMs) allow the surface tailoring through the adsorption of molecular layers having the appropriate functional group or precursor group enabling in situ chemical reactions and thus to the incorporation of new functionalities. The latter approach is particularly advantageous when the incorporation of huge groups is needed. In this study, we report the immobilization of pterin moieties on 11-bromoundecyltrichlorosilane-modified silicon substrates based on the in situ replacement of the bromine groups by pterin (Ptr), the parent derivative of pterins, by means of a nucleophilic substitution reaction. The modified surface was structurally characterized through a multi-technique approach, including high-resolution XPS analysis, contact angle measurements, and AFM. The designed synthesis method leads to the functionalization of the silicon surface with two compounds, O-undecyl-Ptr and N-undecyl-Ptr, with a higher proportion of the N-derivative (1:8 ratio). The alkyl-pterins immobilized via the proposed strategy, retain their photochemical properties, being able to inhibit Staphylococcus aureus growth under irradiation (84.3 ± 15.6 % reduction in viable cells). Our results open the possibility for the modification of several materials, such as glass and metal, through the formation of SAMs having the proper head group, thus allowing the design of photosensitive surfaces with potential microbiological self-cleaning properties.


Assuntos
Silício , Staphylococcus aureus , Fármacos Fotossensibilizantes , Pterinas , Propriedades de Superfície
4.
Sci Total Environ ; 753: 141915, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33207447

RESUMO

In this study we focused on urban bird diversity across Mexico, a megadiverse country, with a special focus on the relative role of urban greenspaces and heavily-built sites. We considered a country-wide approach, including 24 different sized Mexican cities. Our aims were to describe the urban bird diversity in focal cities and further assess the relationships between it and the biogeographic region where cities are located, their size, elevation, and annual rainfall. Additionally, we evaluated differences in the functional composition of bird communities in both studied urban scenarios (i.e., urban greenspaces, heavily-built sites). Our results confirm that urban greenspaces are home to a large proportion of species when contrasted with heavily-built sites. While total species richness and species richness of greenspaces were related with the cities' biogeographic region -with higher species richness in the Neotropical region and Transition Zone-, the relationship did not hold true in heavily-built sites. We found that annual rainfall was negatively related to bird richness in heavily-built sites, suggesting that species from arid systems can be more tolerant to urbanization. Regarding the bird functional group assessment, results show a clear differentiation between the functional groups of greenspaces and those of heavily-built sites, with granivores and omnivores associated with the latter and a highly diverse array of functional groups associated with urban greenspaces.


Assuntos
Biodiversidade , Aves , Animais , Cidades , Ecossistema , México , Urbanização
5.
Biotechnol Rep (Amst) ; 26: e00456, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32373484

RESUMO

Technological advances allowed the development of high-throughput instruments such as IntelliCyt iQue Screener PLUS®. Here, we took advantage of this technology to transfer a previously validated cytotoxicity assay. The evaluated parameters were cell permeability, caspase activation and phosphatidyl serine exposure. The assay was accurate (r2 = 0.90), precise (%CV ≤ 18.90) and specific. These results showed that this technology is suitable to be used in control quality environments. In addition, the automation provided a faster acquisition and analysis of data with precise and accurate results. This application could be implemented to evaluate another in vitro mechanism of action of different biotherapeutics.

6.
Biotechnol Rep (Amst) ; 22: e00331, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31061815

RESUMO

The biotherapeutic type I interferons (IFN-I) are indicated to treat several diseases. These products are regulated to guarantee safety and efficacy through critical quality attributes. For this purpose, the development of robust assays is required, followed by its validation to demonstrate their suitability for its intended purpose. Despite there are some commercial kits to evaluate IFN-I signaling, these are focused on measuring in vitro biological response instead of their validation, which is a pharmaceutical industry requirement. The aim of this work was to validate the HEK-Blue IFN-α/ß system evaluating the biological activity of IFN-α/ß under good laboratory practices, according to international standards. Our results demonstrated that HEK-Blue IFN-α/ß system comply with accuracy (r2>0.95) precision (CV < 20%) and specificity for both IFN-α/ß; confirming that this assay is robust for this biotherapeutics' evaluation. Thereby, this bioassay could be implemented as a complementary method to the classical anti-proliferative and anti-viral assays under quality control environments.

7.
J Immunol Methods ; 464: 87-94, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30395815

RESUMO

The development of biotherapeutics requires continuous improvement in analytical methodologies for the assessment of their quality attributes. A subset of biotherapeutics is designed to interact with specific antigens that are exposed on the membranes of target cells or circulating in a soluble form, and effector functions are achieved via recognition of their Fc region by effector cells that induce mechanisms such as antibody-dependent cell-mediated cytotoxicity (ADCC). Thus, ADCC induction is a critical quality attribute (CQA) that must be evaluated to ensure biotherapeutic efficacy. Induction of ADCC can be evaluated by employing effector cells from different sources, such as peripheral blood mononuclear cells (PBMC) and genetically modified cell lines (e.g., transfected NKs or Jurkat cells), and different approaches can be used for detection and results interpretation depending on the type of effector cells used. In this regard, validation of the assays is relevant to ensure the reliability of the results according to the intended purpose. Herein, we show the standardization and validation of ADCC assays to test the potency of three biotherapeutic proteins using primary NK cells obtained from fresh blood as effector cells and detecting cell death by flow cytometry. The advantage of using primary NKs instead of modified cells is that the response is closer to that occurring in vivo since cytotoxicity is evaluated in a direct manner. Our results indicate that in all cases, the assays exhibited a characteristic sigmoidal dose/response curve complying with accurate, precise and specific parameters. Thereby, the validated ADCC assay is an appropriate alternative to evaluate the biological activities of these type of biotherapeutics.


Assuntos
Adalimumab/farmacologia , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Antineoplásicos Imunológicos/farmacologia , Linfoma de Burkitt/tratamento farmacológico , Separação Celular/métodos , Etanercepte/farmacologia , Citometria de Fluxo , Células Matadoras Naturais/efeitos dos fármacos , Rituximab/farmacologia , Animais , Linfoma de Burkitt/imunologia , Linfoma de Burkitt/patologia , Células CHO , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cricetulus , Relação Dose-Resposta a Droga , Humanos , Células Matadoras Naturais/imunologia , Cultura Primária de Células , Reprodutibilidade dos Testes
8.
Front Med (Lausanne) ; 5: 272, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30320117

RESUMO

Biotherapeutic products which are derived from living organisms using recombinant DNA technology significantly contribute to the progress in the treatment of life-threatening and chronic diseases. The worldwide sale of biological drugs in 2016 was near US $263,700 million. In Latin America, where monoclonal antibodies market was worth US $7000 million, being Mexico the second largest market. Approval is one of the key aspects which influences the market of medicinal products, thus it is responsibility of the regulatory authority to establish a regulatory framework that ensure safety and efficacy of the products, and it is responsibility of the applicants to provide a high quality dossier in accordance with the registration requirements of the country. The applicants submitting registration requests in Mexico need to be aware of the requirements. Similar to many other countries, Mexico has adopted the Common Technical Document (CTD) structure for organizing dossier of the medicinal product for submission into main modules (i.e., quality, non-clinical, and clinical). This facilitates the submission process of medicinal products following a logical sequence aligned to the International Council on Harmonisation (ICH) guidelines. Moreover, this structure improves the transparency and clarity of the dossier in process of evaluation of medicinal products. In Mexico, the Ministry of Health has published a regulation, NOM-257-SSA1-2014, which established the general requirements to be followed by applicants to complete the registration of biotherapeutics. This regulation stipulates that the evaluation process is supported by a regulatory framework involving Good Manufacturing Practices, labeling, stability, clinical trials, biocomparability studies, pharmacovigilance, and a technical evaluation performed by a multidisciplinary team of experts in biotherapeutics development. Additionally, the Mexican regulatory agency, COFEPRIS, has published specific guidelines to facilitate the application process. Despite the availability of this information, the scope is limited to regulatory and administrative purposes, rather than technical-scientific supporting knowledge. The aim of this article is to provide concise information to improve and promote communication between industry and regulatory agencies. Herein, we describe the current process of COFEPRIS in regulating biotherapeutics in Mexico. This process explains the basis for the organization and structure of the technical-scientific information of biotherapeutics required for registration application.

9.
J Pharm Biomed Anal ; 155: 235-240, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29653347

RESUMO

Physicochemical and structural properties of proteins used as active pharmaceutical ingredients of biopharmaceuticals are determinant to carry out their biological activity. In this regard, the assays intended to evaluate functionality of biopharmaceuticals provide confirmatory evidence that they contain the appropriate physicochemical properties and structural conformation. The validation of the methodologies used for the assessment of critical quality attributes of biopharmaceuticals is a key requirement for manufacturing under GMP environments. Herein we present the development and validation of a flow cytometry-based methodology for the evaluation of adalimumab's affinity towards membrane-bound TNFα (mTNFα) on recombinant CHO cells. This in vitro methodology measures the interaction between an in-solution antibody and its target molecule onto the cell surface through a fluorescent signal. The characteristics evaluated during the validation exercise showed that this methodology is suitable for its intended purpose. The assay demonstrated to be accurate (r2 = 0.92, slope = 1.20), precise (%CV ≤ 18.31) and specific (curve fitting, r2 = 0.986-0.997) to evaluate binding of adalimumab to mTNFα. The results obtained here provide evidence that detection by flow cytometry is a viable alternative for bioassays used in the pharmaceutical industry. In addition, this methodology could be standardized for the evaluation of other biomolecules acting through the same mechanism of action.


Assuntos
Adalimumab/metabolismo , Bioensaio/métodos , Membrana Celular/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Células CHO , Cricetulus , Citometria de Fluxo/métodos , Padrões de Referência
10.
Nucleic Acids Res ; 46(D1): D645-D648, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29136215

RESUMO

Multitasking, or moonlighting, is the capability of some proteins to execute two or more biological functions. MultitaskProtDB-II is a database of multifunctional proteins that has been updated. In the previous version, the information contained was: NCBI and UniProt accession numbers, canonical and additional biological functions, organism, monomeric/oligomeric states, PDB codes and bibliographic references. In the present update, the number of entries has been increased from 288 to 694 moonlighting proteins. MultitaskProtDB-II is continually being curated and updated. The new database also contains the following information: GO descriptors for the canonical and moonlighting functions, three-dimensional structure (for those proteins lacking PDB structure, a model was made using Itasser and Phyre), the involvement of the proteins in human diseases (78% of human moonlighting proteins) and whether the protein is a target of a current drug (48% of human moonlighting proteins). These numbers highlight the importance of these proteins for the analysis and explanation of human diseases and target-directed drug design. Moreover, 25% of the proteins of the database are involved in virulence of pathogenic microorganisms, largely in the mechanism of adhesion to the host. This highlights their importance for the mechanism of microorganism infection and vaccine design. MultitaskProtDB-II is available at http://wallace.uab.es/multitaskII.


Assuntos
Bases de Dados de Proteínas , Humanos , Internet , Dobramento de Proteína , Proteínas/química , Proteínas/genética , Proteínas/metabolismo , Interface Usuário-Computador
11.
J Colloid Interface Sci ; 496: 456-464, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28254612

RESUMO

The encapsulation of fluorescent dyes inside silica nanoparticles is advantageous to improve their quality as probes. Inside the particle, the fluorophore is protected from the external conditions and its main emission parameters remains unchanged even in the presence of quenchers. On the other hand, the amine-functionalized nanoparticle surface enables a wide range of applications, as amino groups could be easily linked with different biomolecules for targeting purposes. This kind of nanoparticle is regularly synthesized by methods that employ templates, additional nanoparticle formation or multiple pathway process. However, a one-step synthesis will be an efficient approach in this sort of bifunctional hybrid nanoparticles. A co-condensation sol-gel synthesis of hybrid fluorescent silica nanoparticle where developed. The chemical and morphological characterization of the particles where investigated by DRIFTS, XPS, SEM and SAXS. The nanoparticle fluorescent properties were also assessed by excitation-emission matrices and time resolved experiments. We have developed a one-pot synthesis method that enables the simultaneous incorporation of functionalities, the fluorescent molecule and the amino group, by controlling co-condensation process. An exhaustive characterization allows the definition of the spatial distribution of the fluorescent probe, fluorescein isothiocyanate, inside the particle and reactive amino groups on the surface of the nanoparticle with diameter about 100nm.


Assuntos
Corantes Fluorescentes/química , Nanopartículas/química , Dióxido de Silício/química , Fluoresceína/análise , Fluoresceína/química , Corantes Fluorescentes/análise , Propriedades de Superfície
12.
Int J Billing ; 19(6): 693-702, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26640399

RESUMO

AIMS AND OBJECTIVES/PURPOSE/RESEARCH QUESTIONS: Following reports showing bilingual advantages in executive control (EC) performance, the current study investigated the role of selective attention as a foundational skill that might underlie these advantages. DESIGN/METHODOLOGY/APPROACH: Bilingual and monolingual young adults performed a visual search task by determining whether a target shape was present amid distractor shapes. Task difficulty was manipulated by search type (feature or conjunction) and by the number and discriminability of the distractors. In feature searches, the target (e.g., green triangle) differed on a single dimension (e.g., color) from the distractors (e.g., yellow triangles); in conjunction searches, two types of distractors (e.g., pink circles and turquoise squares) each differed from the target (e.g., turquoise circle) on a single but different dimension (e.g., color or shape). DATA AND ANALYSIS: Reaction time and accuracy data from 109 young adults (53 monolinguals and 56 bilinguals) were analyzed using a repeated-measures analysis of variance. Group membership, search type, number and discriminability of distractors were the independent variables. FINDINGS/CONCLUSIONS: Participants identified the target more quickly in the feature searches, when the target was highly discriminable from the distractors and when there were fewer distractors. Importantly, although monolinguals and bilinguals performed equivalently on the feature searches, bilinguals were significantly faster than monolinguals in identifying the target in the more difficult conjunction search, providing evidence for better control of visual attention in bilinguals. ORIGINALITY: Unlike previous studies on bilingual visual attention, the current study found a bilingual attention advantage in a paradigm that did not include a Stroop-like manipulation to set up false expectations. SIGNIFICANCE/IMPLICATIONS: Thus, our findings indicate that the need to resolve explicit conflict or overcome false expectations is unnecessary for observing a bilingual advantage in selective attention. Observing this advantage in a fundamental skill suggests that it may underlie higher order bilingual advantages in EC.

13.
Artigo em Inglês | MEDLINE | ID: mdl-26157797

RESUMO

Multitasking or moonlighting is the capability of some proteins to execute two or more biochemical functions. Usually, moonlighting proteins are experimentally revealed by serendipity. For this reason, it would be helpful that Bioinformatics could predict this multifunctionality, especially because of the large amounts of sequences from genome projects. In the present work, we analyze and describe several approaches that use sequences, structures, interactomics, and current bioinformatics algorithms and programs to try to overcome this problem. Among these approaches are (a) remote homology searches using Psi-Blast, (b) detection of functional motifs and domains, (c) analysis of data from protein-protein interaction databases (PPIs), (d) match the query protein sequence to 3D databases (i.e., algorithms as PISITE), and (e) mutation correlation analysis between amino acids by algorithms as MISTIC. Programs designed to identify functional motif/domains detect mainly the canonical function but usually fail in the detection of the moonlighting one, Pfam and ProDom being the best methods. Remote homology search by Psi-Blast combined with data from interactomics databases (PPIs) has the best performance. Structural information and mutation correlation analysis can help us to map the functional sites. Mutation correlation analysis can only be used in very specific situations - it requires the existence of multialigned family protein sequences - but can suggest how the evolutionary process of second function acquisition took place. The multitasking protein database MultitaskProtDB (http://wallace.uab.es/multitask/), previously published by our group, has been used as a benchmark for the all of the analyses.

14.
Biochem Soc Trans ; 42(6): 1692-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25399591

RESUMO

Protein multitasking or moonlighting is the capability of certain proteins to execute two or more unique biological functions. This ability to perform moonlighting functions helps us to understand one of the ways used by cells to perform many complex functions with a limited number of genes. Usually, moonlighting proteins are revealed experimentally by serendipity, and the proteins described probably represent just the tip of the iceberg. It would be helpful if bioinformatics could predict protein multifunctionality, especially because of the large amounts of sequences coming from genome projects. In the present article, we describe several approaches that use sequences, structures, interactomics and current bioinformatics algorithms and programs to try to overcome this problem. The sequence analysis has been performed: (i) by remote homology searches using PSI-BLAST, (ii) by the detection of functional motifs, and (iii) by the co-evolutionary relationship between amino acids. Programs designed to identify functional motifs/domains are basically oriented to detect the main function, but usually fail in the detection of secondary ones. Remote homology searches such as PSI-BLAST seem to be more versatile in this task, and it is a good complement for the information obtained from protein-protein interaction (PPI) databases. Structural information and mutation correlation analysis can help us to map the functional sites. Mutation correlation analysis can be used only in very restricted situations, but can suggest how the evolutionary process of the acquisition of the second function took place.


Assuntos
Biologia Computacional , Proteínas/fisiologia , Mutação , Conformação Proteica , Proteínas/química , Proteínas/genética , Homologia de Sequência de Aminoácidos
15.
Cognition ; 130(3): 278-88, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24374020

RESUMO

One hundred and seventy-five children who were 6-years old were assigned to one of four groups that differed in socioeconomic status (SES; working class or middle class) and language background (monolingual or bilingual). The children completed tests of nonverbal intelligence, language tests assessing receptive vocabulary and attention based on picture naming, and two tests of executive functioning. All children performed equivalently on the basic intelligence tests, but performance on the language and executive functioning tasks was influenced by both SES and bilingualism. Middle-class children outperformed working-class children on all measures, and bilingual children obtained lower scores than monolingual children on language tests but higher scores than monolingual children on the executive functioning tasks. There were no interactions with either group factors or task factors. Thus, each of SES and bilingualism contribute significantly and independently to children's development irrespective of the child's level on the other factor.


Assuntos
Função Executiva/fisiologia , Idioma , Multilinguismo , Classe Social , Criança , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia
16.
Immunology ; 139(4): 459-71, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23432484

RESUMO

Salmonella enterica serovar Typhi (S. Typhi) is the causal agent of typhoid fever, a disease that primarily affects developing countries. Various antigens from this bacterium have been reported to be targets of the immune response. Recently, the S. Typhi genome has been shown to encode two porins--OmpS1 and OmpS2--which are expressed at low levels under in vitro culture conditions. In this study, we demonstrate that immunizing mice with either OmpS1 or OmpS2 induced production of specific, long-term antibody titres and conferred protection against S. Typhi challenge; in particular, OmpS1 was more immunogenic and conferred greater protective effects than OmpS2. We also found that OmpS1 is a Toll-like receptor 4 (TLR4) agonist, whereas OmpS2 is a TLR2 and TLR4 agonist. Both porins induced the production of tumour necrosis factor and interleukin-6, and OmpS2 was also able to induce interleukin-10 production. Furthermore, OmpS1 induced the over-expression of MHC II molecules in dendritic cells and OmpS2 induced the over-expression of CD40 molecules in macrophages and dendritic cells. Co-immunization of OmpS1 or OmpS2 with ovalbumin (OVA) increased anti-OVA antibody titres, the duration and isotype diversity of the OVA-specific antibody response, and the proliferation of T lymphocytes. These porins also had adjuvant effects on the antibody response when co-immunized with either the Vi capsular antigen from S. Typhi or inactivated 2009 pandemic influenza A(H1N1) virus [A(H1N1)pdm09]. Taken together, the data indicate that OmpS1 and OmpS2, despite being expressed at low levels under in vitro culture conditions, are potent protective immunogens with intrinsic adjuvant properties.


Assuntos
Adjuvantes Imunológicos , Anticorpos Antibacterianos/sangue , Proteínas da Membrana Bacteriana Externa/imunologia , Porinas/imunologia , Vacinas contra Salmonella/imunologia , Salmonella typhi/imunologia , Febre Tifoide/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/genética , Animais , Proteínas da Membrana Bacteriana Externa/administração & dosagem , Proteínas da Membrana Bacteriana Externa/genética , Células Dendríticas/imunologia , Relação Dose-Resposta a Droga , Feminino , Células HEK293 , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunização , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Ativação Linfocitária , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Ovalbumina/imunologia , Polissacarídeos Bacterianos/imunologia , Porinas/administração & dosagem , Porinas/genética , Vacinas contra Salmonella/administração & dosagem , Vacinas contra Salmonella/genética , Salmonella typhi/genética , Linfócitos T/imunologia , Fatores de Tempo , Receptor 2 Toll-Like/agonistas , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/metabolismo , Transfecção , Fator de Necrose Tumoral alfa/metabolismo , Febre Tifoide/sangue , Febre Tifoide/imunologia , Febre Tifoide/microbiologia
17.
J Exp Child Psychol ; 114(2): 187-202, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23059128

RESUMO

Two studies are reported comparing the performance of monolingual and bilingual children on tasks requiring different levels of working memory. In the first study, 56 5-year-olds performed a Simon-type task that manipulated working memory demands by comparing conditions based on two rules and four rules and manipulated conflict resolution demands by comparing conditions that included conflict with those that did not. Bilingual children responded faster than monolinguals on all conditions and bilinguals were more accurate than monolinguals in responding to incongruent trials, confirming an advantage in aspects of executive functioning. In the second study, 125 children 5- or 7-year-olds performed a visuospatial span task that manipulated other executive function components through simultaneous or sequential presentation of items. Bilinguals outperformed monolinguals overall, but again there were larger language group effects in conditions that included more demanding executive function requirements. Together, the studies show an advantage for bilingual children in working memory that is especially evident when the task contains additional executive function demands.


Assuntos
Percepção de Cores , Lateralidade Funcional , Memória de Curto Prazo , Multilinguismo , Orientação , Reconhecimento Visual de Modelos , Desempenho Psicomotor , Atenção , Criança , Pré-Escolar , Conflito Psicológico , Função Executiva , Feminino , Humanos , Masculino , Resolução de Problemas
18.
Vaccine ; 29(44): 7826-34, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21816199

RESUMO

Virus-like particles (VLPs) can be rapidly developed from influenza virus genetic sequences in order to supply vaccine after the onset of a pandemic. The safety and immunogenicity of one or two doses of a recombinant A (H1N1) 2009 influenza VLP vaccine was evaluated in a two-stage, Phase 2, randomized, double-blind, placebo-controlled study conducted in 4563 healthy adults, 18-64 years of age, during the H1N1 2009 pandemic in Mexico. In Part A, 1013 subjects were randomized into four treatment groups (5 µg, 15 µg, or 45 µg hemagglutinin [HA] VLP vaccine or placebo) and vaccinated 21 days apart, with sera collected on Days 1, 14 and 36 for hemagglutination inhibition (HAI) testing. After review of safety and immunogenicity data from Part A, additional subjects were immunized with a single dose of 15 µg VLP vaccine (N=2537) or placebo (N=1011) and assessed for safety in Part B. Results showed the H1N1 2009 VLP vaccine was safe and well-tolerated. Systemic solicited events were similar between placebo and VLP vaccinated groups with no vaccine-related serious adverse events. Dose response trends for solicited local adverse events were observed, with higher incidences of local pain, swelling, tenderness, and redness reported in the higher VLP dose groups (15 µg and 45 µg) compared to the placebo and 5 µg VLP groups following both vaccinations. Although the majority of local AEs were mild in severity, a dose trend in events of moderate or greater severity was also noted for these solicited events. The VLP vaccine groups demonstrated robust HAI immune responses after a single vaccination, with high rates of seroprotection (≥ 40 HAI titer) in 82-92% of all subjects and in 64-85% of subjects who were seronegative at the time of immunization. HAI geometric mean titers (GMTs), geometric mean ratios (GMRs) and seroconversion rates were also all statistically higher in the VLP groups compared to placebo for both post-baseline time points. Based on these data, additional clinical trials are in development to evaluate influenza vaccine candidate antigens manufactured using Spodoptera frugiperda (Sf9)/baculovirus-based VLP technology.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Vacinação/métodos , Adolescente , Adulto , Idoso , Animais , Anticorpos Antivirais/sangue , Baculoviridae/genética , Linhagem Celular , Método Duplo-Cego , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vacinas contra Influenza/administração & dosagem , Masculino , México , Pessoa de Meia-Idade , Placebos/administração & dosagem , Spodoptera , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/imunologia , Vacinas Virossomais/administração & dosagem , Vacinas Virossomais/efeitos adversos , Vacinas Virossomais/imunologia , Adulto Jovem
19.
Langmuir ; 27(8): 4328-33, 2011 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-21425821

RESUMO

The design of hybrid mesoporous materials incorporating polymeric assemblies as versatile functional units has become a very fertile research area offering major opportunities for controlling molecular transport through interfaces. However, the creation of such functional materials depends critically on our ability to assemble polymeric units in a predictable manner within mesopores with dimensions comparable to the size of the macromolecular blocks themselves. In this work, we describe for the first time the manipulation of the molecular transport properties of mesoporous silica thin films by the direct infiltration of polyelectrolytes into the inner environment of the 3D porous framework. The hybrid architectures were built up through the infiltration-electrostatic assembly of polyallylamine (PAH) on the mesopore silica walls, and the resulting systems were studied by a combination of experimental techniques including ellipso-porosimetry, cyclic voltammetry and X-ray photoelectron spectroscopy, among others. Our results show that the infiltration-assembly of PAH alters the intrinsic cation-permselective properties of mesoporous silica films, rendering them ion-permeable mesochannels and enabling the unrestricted diffusion of cationic and anionic species through the hybrid interfacial architecture. Contrary to what happens during the electrostatic assembly of PAH on planar silica films (quantitative charge reversal), the surface charge of the mesoporous walls is completely neutralized upon assembling the cationic PAH layer (i.e., no charge reversal occurs). We consider this work to have profound implications not only on the molecular design of multifunctional mesoporous thin films but also on understanding the predominant role of nanoconfinement effects in dictating the functional properties of polymer-inorganic hybrid nanomaterials.


Assuntos
Eletrólitos , Polímeros , Dióxido de Silício/química , Membranas Artificiais , Nanoestruturas , Permeabilidade , Porosidade
20.
J Exp Psychol Learn Mem Cogn ; 37(2): 308-24, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21299326

RESUMO

The ability to temporarily maintain information in order to successfully perform a task is important in many daily activities. However, the ability to quickly and accurately update existing mental representations in distracting situations is also imperative in many of these same circumstances. In the current studies, individuals varying in working memory capacity (WMC) performed different varieties of go/no-go tasks that have been hypothesized to measure inhibitory ability. The results indicated that low-WMC individuals relative to high-WMC individuals showed worse performance specifically in certain conditions of the conditional go/no-go task. Further analyses showed that increasing the temporal lag/number of intervening items between the previous target and the current lure had a deleterious effect on the performance of the low-WMC group only. The results indicate a relationship between WMC and the ability to selectively update, maintain, and retrieve information, especially in interference-rich conditions.


Assuntos
Tomada de Decisões/fisiologia , Função Executiva/fisiologia , Inibição Psicológica , Memória de Curto Prazo/fisiologia , Retenção Psicológica , Detecção de Sinal Psicológico/fisiologia , Adolescente , Adulto , Análise de Variância , Retroalimentação Sensorial , Feminino , Humanos , Individualidade , Masculino , Matemática , Testes Neuropsicológicos , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto Jovem
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