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1.
Lima; Perú. Ministerio de Salud; 20200900. 10 p.
Monografia em Espanhol | LILACS, MINSAPERU | ID: biblio-1118773

RESUMO

El documento contiene las pautas para garantizar la seguridad, calidad y desempeño en el desarrollo y validación de proyectos de investigación vinculados a los dispositivos de diagnóstico in vitro (DMDIVD), que permitan una autorización para la fabricación y uso.


Assuntos
Pesquisa , Projetos de Pesquisa , Técnicas In Vitro , Infecções por Coronavirus , Diagnóstico , Equipamentos e Provisões
2.
PLoS Biol ; 18(9): e3000873, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32966273

RESUMO

The inhibitory axonless olfactory bulb granule cells form reciprocal dendrodendritic synapses with mitral and tufted cells via large spines, mediating recurrent and lateral inhibition. As a case in point for dendritic transmitter release, rat granule cell dendrites are highly excitable, featuring local Na+ spine spikes and global Ca2+- and Na+-spikes. To investigate the transition from local to global signaling, we performed holographic, simultaneous 2-photon uncaging of glutamate at up to 12 granule cell spines, along with whole-cell recording and dendritic 2-photon Ca2+ imaging in acute juvenile rat brain slices. Coactivation of less than 10 reciprocal spines was sufficient to generate diverse regenerative signals that included regional dendritic Ca2+-spikes and dendritic Na+-spikes (D-spikes). Global Na+-spikes could be triggered in one third of granule cells. Individual spines and dendritic segments sensed the respective signal transitions as increments in Ca2+ entry. Dendritic integration as monitored by the somatic membrane potential was mostly linear until a threshold number of spines was activated, at which often D-spikes along with supralinear summation set in. As to the mechanisms supporting active integration, NMDA receptors (NMDARs) strongly contributed to all aspects of supralinearity, followed by dendritic voltage-gated Na+- and Ca2+-channels, whereas local Na+ spine spikes, as well as morphological variables, barely mattered. Because of the low numbers of coactive spines required to trigger dendritic Ca2+ signals and thus possibly lateral release of GABA onto mitral and tufted cells, we predict that thresholds for granule cell-mediated bulbar lateral inhibition are low. Moreover, D-spikes could provide a plausible substrate for granule cell-mediated gamma oscillations.


Assuntos
Potenciais de Ação , Sinalização do Cálcio , Dendritos/metabolismo , Bulbo Olfatório/metabolismo , Sódio/metabolismo , Animais , Cálcio/metabolismo , Feminino , Holografia , Técnicas In Vitro , Masculino , Ratos Wistar , Receptores de N-Metil-D-Aspartato/metabolismo
3.
Nat Commun ; 11(1): 4454, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901001

RESUMO

Chronic viral infections are often associated with impaired CD8+ T cell function, referred to as exhaustion. Although the molecular and cellular circuits involved in CD8+ T cell exhaustion are well defined, with sustained presence of antigen being one important parameter, how much T cell receptor (TCR) signaling is actually ongoing in vivo during established chronic infection is unclear. Here, we characterize the in vivo TCR signaling of virus-specific exhausted CD8+ T cells in a mouse model, leveraging TCR signaling reporter mice in combination with transcriptomics. In vivo signaling in exhausted cells is low, in contrast to their in vitro signaling potential, and despite antigen being abundantly present. Both checkpoint blockade and adoptive transfer of naïve target cells increase TCR signaling, demonstrating that engagement of co-inhibitory receptors curtails CD8+ T cell signaling and function in vivo.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Coriomeningite Linfocítica/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transferência Adotiva , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/virologia , Doença Crônica , Citotoxicidade Imunológica , Modelos Animais de Doenças , Regulação para Baixo , Tolerância Imunológica , Imunidade Celular , Técnicas In Vitro , Ativação Linfocitária , Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/imunologia , Receptor de Morte Celular Programada 1/imunologia , RNA-Seq , Transdução de Sinais/imunologia
4.
Nat Commun ; 11(1): 4457, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901017

RESUMO

Innate lymphoid cells (ILCs) and CD4+ T cells produce IL-22, which is critical for intestinal immunity. The microbiota is central to IL-22 production in the intestines; however, the factors that regulate IL-22 production by CD4+ T cells and ILCs are not clear. Here, we show that microbiota-derived short-chain fatty acids (SCFAs) promote IL-22 production by CD4+ T cells and ILCs through G-protein receptor 41 (GPR41) and inhibiting histone deacetylase (HDAC). SCFAs upregulate IL-22 production by promoting aryl hydrocarbon receptor (AhR) and hypoxia-inducible factor 1α (HIF1α) expression, which are differentially regulated by mTOR and Stat3. HIF1α binds directly to the Il22 promoter, and SCFAs increase HIF1α binding to the Il22 promoter through histone modification. SCFA supplementation enhances IL-22 production, which protects intestines from inflammation. SCFAs promote human CD4+ T cell IL-22 production. These findings establish the roles of SCFAs in inducing IL-22 production in CD4+ T cells and ILCs to maintain intestinal homeostasis.


Assuntos
Ácidos Graxos Voláteis/imunologia , Microbioma Gastrointestinal/imunologia , Imunidade Inata , Interleucinas/biossíntese , Animais , Butiratos/imunologia , Butiratos/metabolismo , Butiratos/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Citrobacter rodentium , Colite/imunologia , Colite/microbiologia , Colite/prevenção & controle , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/prevenção & controle , Ácidos Graxos Voláteis/metabolismo , Ácidos Graxos Voláteis/farmacologia , Microbioma Gastrointestinal/fisiologia , Inibidores de Histona Desacetilases/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Técnicas In Vitro , Interleucinas/deficiência , Interleucinas/genética , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Regiões Promotoras Genéticas , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo
5.
Nat Microbiol ; 5(10): 1185-1191, 2020 10.
Artigo em Inglês | MEDLINE | ID: covidwho-752497

RESUMO

Antibody-based drugs and vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are being expedited through preclinical and clinical development. Data from the study of SARS-CoV and other respiratory viruses suggest that anti-SARS-CoV-2 antibodies could exacerbate COVID-19 through antibody-dependent enhancement (ADE). Previous respiratory syncytial virus and dengue virus vaccine studies revealed human clinical safety risks related to ADE, resulting in failed vaccine trials. Here, we describe key ADE mechanisms and discuss mitigation strategies for SARS-CoV-2 vaccines and therapies in development. We also outline recently published data to evaluate the risks and opportunities for antibody-based protection against SARS-CoV-2.


Assuntos
Anticorpos Facilitadores , Betacoronavirus , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , Vacinas Virais/efeitos adversos , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Humanos , Imunização Passiva/efeitos adversos , Técnicas In Vitro , Modelos Imunológicos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Doenças Respiratórias/etiologia , Doenças Respiratórias/imunologia , Fatores de Risco , Segurança , Vacinas Virais/imunologia
6.
Nat Microbiol ; 5(10): 1185-1191, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32908214

RESUMO

Antibody-based drugs and vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are being expedited through preclinical and clinical development. Data from the study of SARS-CoV and other respiratory viruses suggest that anti-SARS-CoV-2 antibodies could exacerbate COVID-19 through antibody-dependent enhancement (ADE). Previous respiratory syncytial virus and dengue virus vaccine studies revealed human clinical safety risks related to ADE, resulting in failed vaccine trials. Here, we describe key ADE mechanisms and discuss mitigation strategies for SARS-CoV-2 vaccines and therapies in development. We also outline recently published data to evaluate the risks and opportunities for antibody-based protection against SARS-CoV-2.


Assuntos
Anticorpos Facilitadores , Betacoronavirus , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , Vacinas Virais/efeitos adversos , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Humanos , Imunização Passiva/efeitos adversos , Técnicas In Vitro , Modelos Imunológicos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Doenças Respiratórias/etiologia , Doenças Respiratórias/imunologia , Fatores de Risco , Segurança , Vacinas Virais/imunologia
7.
Rev. Asoc. Odontol. Argent ; 108(2): 46-51, mayo-ago. 2020. tab
Artigo em Espanhol | LILACS | ID: biblio-1121108

RESUMO

Objetivos: Comparar ex vivo la eficacia del instrumento XP-endo Finisher y del sistema EndoActivator en la reducción/eliminación del biofilm microbiano en conductos radiculares infectados. Materiales y métodos: Se utilizaron 23 premolares inferiores humanos extraídos cuya longitud fue estandarizada en 17 mm. Todos los conductos se prepararon con el sistema WaveOne Gold Medium (#35.06). Los dientes se esterilizaron, se inocularon con Enterococcus faecalis y se separaron en dos grupos experimentales de 10 piezas cada uno. De los 3 dientes remanentes, 1 fue utilizado como control positivo y 2, como controles negativos. En el grupo 1, las soluciones irrigantes se agitaron con XP-endo Finisher. En el grupo 2, se utilizó EndoActivator. Se tomaron muestras antes de la contaminación, luego de esta y después de la agitación de los irrigantes mediante conos de papel estériles. La carga microbiana fue sembrada en agar sangre y los conos se cultivaron en caldo tripteína de soja. La remoción de la carga microbiana se determinó por la presencia o ausencia de turbiedad del medio. Las unidades formadoras de colonias (UFC) remanentes se cuantificaron y los resultados se categorizaron como R1 (≤10 UFC) o R2 (>10 UFC). Los datos fueron analizados mediante la prueba de Fisher. Resultados: No hubo diferencias significativas entre XP-endo Finisher y EndoActivator (P>0,05). El número de usos no influyó sobre la capacidad operativa de ambos instrumentos (AU)


Aim: To compare ex vivo the effectiveness of the XP-endo Finisher and the EndoActivator in biofilm reduction/ removal from infected root canals. Materials and methods: Twenty three extracted human single-rooted lower premolars were selected and standardised to 17 mm in length. All the canals were prepared with WaveOne Gold Medium reciprocating files (#35.06). The teeth were autoclaved and inoculated with Enterococcus faecalis. The infected teeth were then assigned to 2 experimental groups of 10 teeth each according to the final irrigation/agitation protocol. Of the three remaining teeth, one was used as a positive control, and the other two were used as negative controls. In Group 1 the irrigating solutions were agitated with XP-endo Finisher while in Group 2 the EndoActivator was used. All root canals were sampled before and after contamination, and again after irrigant agitation with sterile paper points. The microbial load was spread on blood agar plates and the paper points were cultured in sterile trypticase soy broth. The removal of the microbial load was determined by visual observation of the turbidity of the media and by quantification of the number of colony-forming units (UFC). The results were categorized as R1 (≤10 UFC) or R2 (>10 UFC). Data were analysed by the Fisher's exact test at P<0.05. Results: No significant differences was found between XP-endo Finisher and EndoActivator (P>0.05) regarding their effectiveness in the reduction/removal of the microbial biofilm. The number of uses of both instruments did not affect their operative performance (AU) Conclusion: XPF and EA were both equally effective for microbial biofilm reduction/removal from ex vivo infected root canals (AU)


Assuntos
Irrigantes do Canal Radicular/química , Equipamentos Odontológicos de Alta Rotação , Biofilmes , Instrumentos Odontológicos , Cavidade Pulpar/microbiologia , Técnicas In Vitro , Contagem de Colônia Microbiana/métodos , Eficácia , Análise Estatística , Enterococcus faecalis/isolamento & purificação , Meios de Cultura
8.
Sci Transl Med ; 12(557)2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32747425

RESUMO

Pathogenic coronaviruses are a major threat to global public health, as exemplified by severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and the newly emerged SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19). We describe herein the structure-guided optimization of a series of inhibitors of the coronavirus 3C-like protease (3CLpro), an enzyme essential for viral replication. The optimized compounds were effective against several human coronaviruses including MERS-CoV, SARS-CoV, and SARS-CoV-2 in an enzyme assay and in cell-based assays using Huh-7 and Vero E6 cell lines. Two selected compounds showed antiviral effects against SARS-CoV-2 in cultured primary human airway epithelial cells. In a mouse model of MERS-CoV infection, administration of a lead compound 1 day after virus infection increased survival from 0 to 100% and reduced lung viral titers and lung histopathology. These results suggest that this series of compounds has the potential to be developed further as antiviral drugs against human coronaviruses.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/química , Betacoronavirus/fisiologia , Linhagem Celular , Chlorocebus aethiops , Infecções por Coronavirus/patologia , Cristalografia por Raios X , Cisteína Endopeptidases/química , Modelos Animais de Doenças , Humanos , Técnicas In Vitro , Pulmão/patologia , Pulmão/virologia , Masculino , Camundongos , Camundongos Transgênicos , Testes de Sensibilidade Microbiana , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Modelos Moleculares , Pandemias , Inibidores de Proteases/química , Bibliotecas de Moléculas Pequenas , Especificidade da Espécie , Eletricidade Estática , Pesquisa Médica Translacional , Células Vero , Carga Viral/efeitos dos fármacos , Proteínas não Estruturais Virais/química
9.
Cardiol Rev ; 28(5): 266-271, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32769401

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to be a threat to the health of many humans across the world as they confront coronavirus disease 2019 (COVID-19). Previous promising in vitro data that emerged after the SARS-CoV outbreak in 2003, along with the emergent need for pharmacologic management strategies in the fight against COVID-19, prompted interest in the use of chloroquine and hydroxychloroquine across the globe. Unfortunately, the in vitro activity of these drugs did not necessarily correlate with most in vivo studies, which showed no consistent efficacy. Safety is also a major concern, with these agents having a known risk of QT prolongation and proarrhythmic effects. In addition, clinical practice guidelines provide no clear consensus on the role of chloroquine or hydroxychloroquine for the management of COVID-19. The United States Food and Drug Administration has declared that the potential benefits of these agents no longer outweigh the possible risks, and unless new emerging information suggests a more favorable risk:benefit ratio, neither chloroquine nor hydroxychloroquine should be recommended for COVID-19 treatment or prevention at this time.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Cloroquina/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Hidroxicloroquina/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Betacoronavirus , Citocromo P-450 CYP2D6/metabolismo , Interações Medicamentosas , Humanos , Técnicas In Vitro , Síndrome do QT Longo/induzido quimicamente , Pandemias , Guias de Prática Clínica como Assunto , Torsades de Pointes/induzido quimicamente , Resultado do Tratamento
10.
Nat Commun ; 11(1): 4258, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848127

RESUMO

Protein misfolding causes a wide spectrum of human disease, and therapies that target misfolding are transforming the clinical care of cystic fibrosis. Despite this success, however, very little is known about how disease-causing mutations affect the de novo folding landscape. Here we show that inherited, disease-causing mutations located within the first nucleotide-binding domain (NBD1) of the cystic fibrosis transmembrane conductance regulator (CFTR) have distinct effects on nascent polypeptides. Two of these mutations (A455E and L558S) delay compaction of the nascent NBD1 during a critical window of synthesis. The observed folding defect is highly dependent on nascent chain length as well as its attachment to the ribosome. Moreover, restoration of the NBD1 cotranslational folding defect by second site suppressor mutations also partially restores folding of full-length CFTR. These findings demonstrate that nascent folding intermediates can play an important role in disease pathogenesis and thus provide potential targets for pharmacological correction.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Mutação , Substituição de Aminoácidos , Sítios de Ligação/genética , Fibrose Cística/genética , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/química , Células HEK293 , Humanos , Técnicas In Vitro , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Domínios Proteicos , Dobramento de Proteína , Modificação Traducional de Proteínas/genética , Estabilidade Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ribossomos/metabolismo , Supressão Genética , Temperatura
11.
Nat Commun ; 11(1): 4276, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848151

RESUMO

The structural organization of excitatory inputs supporting spike-timing-dependent plasticity (STDP) remains unknown. We performed a spine STDP protocol using two-photon (2P) glutamate uncaging (pre) paired with postsynaptic spikes (post) in layer 5 pyramidal neurons from juvenile mice. Here we report that pre-post pairings that trigger timing-dependent LTP (t-LTP) produce shrinkage of the activated spine neck and increase in synaptic strength; and post-pre pairings that trigger timing-dependent LTD (t-LTD) decrease synaptic strength without affecting spine shape. Furthermore, the induction of t-LTP with 2P glutamate uncaging in clustered spines (<5 µm apart) enhances LTP through a NMDA receptor-mediated spine calcium accumulation and actin polymerization-dependent neck shrinkage, whereas t-LTD was dependent on NMDA receptors and disrupted by the activation of clustered spines but recovered when separated by >40 µm. These results indicate that synaptic cooperativity disrupts t-LTD and extends the temporal window for the induction of t-LTP, leading to STDP only encompassing LTP.


Assuntos
Espinhas Dendríticas/fisiologia , Plasticidade Neuronal/fisiologia , Potenciais de Ação/fisiologia , Animais , Sinalização do Cálcio/fisiologia , Técnicas In Vitro , Potenciação de Longa Duração/fisiologia , Depressão Sináptica de Longo Prazo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência por Excitação Multifotônica , Modelos Neurológicos , Células Piramidais/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia
12.
AAPS PharmSciTech ; 21(6): 227, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32767025

RESUMO

Streptococcus mutans (S. mutans) is the principal etiologic agent in the occurrence of human dental caries and the formation of biofilms on the surface of teeth. Tea tree oil (TTO) has been demonstrated to exhibit a wide range of pharmacological actions that can effectively inhibit the activity of bacteria. In this context, we evaluated the in vitro antimicrobial effects of TTO on S. mutans both during planktonic growth and in biofilms compared with 0.2% CHX. We determined the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) using the microdilution method, the bacteriostatic rate using an MTT assay, and the antimicrobial time using a time-kill assay. Then, we explored the effects of TTO on acid production and cell integrity. Furthermore, the effects of TTO on the biomass and bacterial activity of S. mutans biofilms were studied. Finally, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to investigate the structure and activity of biofilms. The MIC and MBC values were 0.125% and 0.25%, and the bacterial inhibition rate was concentration dependent. TTO can effectively inhibit bacterial acid production and destroy the integrity of the cell membrane. Electron micrographs revealed a reduction in bacterial aggregation, inhibited biofilm formation, and reduced biofilm thickness. The effect of TTO was the same as that of 0.2% CHX at a specific concentration. In summary, we suggest that TTO is a potential anticariogenic agent that can be used against S. mutans.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Óleo de Melaleuca/farmacologia , Cárie Dentária/microbiologia , Humanos , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Microscopia Confocal , Microscopia Eletrônica de Varredura , Streptococcus mutans/efeitos dos fármacos
13.
PLoS One ; 15(8): e0237015, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760098

RESUMO

Graves' orbitopathy (GO) is characterised in early stages by orbital fibroblast inflammation, which can be aggravated by oxidative stress and often leads to fibrosis. Protein tyrosine protein 1B (PTP1B) is a regulator of inflammation and a therapeutic target in diabetes. We investigated the role of PTP1B in the GO mechanism using orbital fibroblasts from GO and healthy non-GO subjects. After 24 hours of transfection with PTPN1 siRNA, the fibroblasts were exposed to interleukin (IL)-1ß, cigarette smoke extract (CSE), H2O2, and transforming growth factor (TGF)-ß stimulations. Inflammatory cytokines and fibrosis-related proteins were analysed using western blotting and/or enzyme-linked immunosorbent assay (ELISA). Reactive oxygen species (ROS) release was detected using an oxidant-sensitive fluorescent probe. IL-1ß, tumor necrosis factor (TNF)-α, bovine thyroid stimulating hormone (bTSH), high-affinity human stimulatory monoclonal antibody of TSH receptor (M22), and insulin-like growth factor-1 (IGF-1) significantly increased PTP1B protein production in GO and non-GO fibroblasts. PTPN1 silencing significantly blocked IL-1ß-induced inflammatory cytokine production, CSE- and H2O2-induced ROS synthesis, and TGF-ß-induced expression of collagen Iα, α-smooth muscle actin (SMA), and fibronectin in GO fibroblasts. Silencing PTPN1 also decreased phosphorylation levels of Akt, p38, and c-Jun N-terminal kinase (JNK) and endoplasmic reticulum (ER)-stress response proteins in GO cells. PTP1B may be a potential therapeutic target of anti-inflammatory, anti-oxidant and anti-fibrotic treatment of GO.


Assuntos
Oftalmopatia de Graves/enzimologia , Oftalmopatia de Graves/terapia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Adulto , Animais , Apoptose , Bovinos , Sobrevivência Celular , Citocinas/biossíntese , Estresse do Retículo Endoplasmático , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Inativação Gênica , Oftalmopatia de Graves/patologia , Humanos , Técnicas In Vitro , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/genética , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
14.
PLoS One ; 15(8): e0236871, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745115

RESUMO

Element bioaccessibility consists of the fraction of the element that is mobilized from food matrices into digestive extractants. The degree of bioaccessibility of a toxic metal is a fundamental consideration in estimating its bioavailability. In addition, gaining a better understanding of the essential elements released into the gastro intestinal fluids allows a more thorough assessment of the health benefits of food matrices in the field of nutrition science. In the present study, an in vitro digestion model simulating gastro-intestinal digestion (GID) was used to investigate the bioaccessibility of stable elements in mixed leaf salad and 210Po in various foods (meat, seafood, vegetables). The simulation was carried out over three phases: after a pre-treatment with a saliva solution, raw and cooked seafood samples were subjected to a complete simulated gastrointestinal digestion (gastric digestion followed by bile-pancreas digestion). The 210Po bioaccessibility was found to range from 16.2±9.39% to 62.8±17.7% and from 6.26±2.15% to 67.5±13.1% for raw and cooked food respectively. Moreover, bioaccessibility could not be determined for As, Cd, Ce, Co, Cr, Hg, La, Pb, Sb, Sn, Te, Th, Tl, Ti, U. It proved to be poor (1-16%) for Al, Fe and S; fair (40-50%) for Cu, P, and Si; and high (>50%) for Ba, Ca, K, Mg, Mn, Ni, Rb, Sr, Zn. The results show that bioaccessibility varies according to the chemical form of the element in the food as well as the matrix composition.


Assuntos
Disponibilidade Biológica , Contaminação de Alimentos/análise , Polônio/análise , Oligoelementos/análise , Digestão , Humanos , Técnicas In Vitro/métodos , Carne/análise , Alimentos Marinhos/análise , Verduras/química
15.
PLoS One ; 15(8): e0234672, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764753

RESUMO

Opticin is a class III member of the extracellular matrix small leucine-rich repeat protein/proteoglycan (SLRP) family found in vitreous humour and cartilage. It was first identified associated with the surface of vitreous collagen fibrils and several other SLRPs are also known to bind collagen fibrils and it some cases alter fibril morphology. The purpose of this study was to investigate the binding of opticin to the collagen II-containing fibrils found in vitreous and cartilage. Electron microscopic studies using gold labelling demonstrated that opticin binds vitreous and thin cartilage collagen fibrils specifically at a single site in the gap region of the collagen D-period corresponding to the e2 stain band; this is the first demonstration of the binding site of a class III SLRP on collagen fibrils. Opticin did not bind thick cartilage collagen fibrils from cartilage or tactoids formed in vitro from collagen II, but shows high specificity for thin, heterotypic collagen fibrils containing collagens II, and XI or V/XI. Vitreous collagen fibrils from opticin null and wild-type mice were compared and no difference in fibril morphology or diameter was observed. Similarly, in vitro fibrillogenesis experiments showed that opticin did not affect fibril formation. We propose that when opticin is bound to collagen fibrils, rather than influencing their morphology it instead hinders the binding of other molecules to the fibril surfaces and/or act as an intermediary bridge linking the collagen fibrils to other non-collagenous molecules.


Assuntos
Colágeno/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteoglicanas/metabolismo , Animais , Sítios de Ligação , Bovinos , Colágeno/química , Colágeno/ultraestrutura , Proteínas da Matriz Extracelular/química , Proteínas da Matriz Extracelular/deficiência , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Microscopia Imunoeletrônica , Ligação Proteica , Proteoglicanas/química , Proteoglicanas/deficiência , Corpo Vítreo/química , Corpo Vítreo/metabolismo , Corpo Vítreo/ultraestrutura
16.
Artif. organs ; 44(8): 785-796, Aug. 2020. gráfico, ilustração, tabela
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1103514

RESUMO

Left ventricular assist devices (LVADs) have been used as a bridge to transplantation or as destination therapy to treat patients with heart failure (HF). The inability of control strategy to respond automatically to changes in hemodynamic conditions can impact the patients' quality of life. The developed control system/algorithm consists of a control system that harmoniously adjusts pump speed without additional sensors, considering the patient's clinical condition and his physical activity. The control system consists of three layers: (a) Actuator speed control; (b) LVAD flow control (FwC); and (c) Fuzzy control system (FzC), with the input variables: heart rate (HR), mean arterial pressure (MAP), minimum pump flow, level of physical activity (data from patient), and clinical condition (data from physician, INTERMACS profile). FzC output is the set point for the second LVAD control schemer (FwC) which in turn adjusts the speed. Pump flow, MAP, and HR are estimated from actuator drive parameters (speed and power). Evaluation of control was performed using a centrifugal blood pump in a hybrid cardiovascular simulator, where the left heart function is the mechanical model and right heart function is the computational model. The control system was able to maintain MAP and cardiac output in the physiological level, even under variation of EF. Apart from this, also the rotational pump speed is adjusted following the simulated clinical condition. No backflow from the aorta in the ventricle occurred through LVAD during tests. The control algorithm results were considered satisfactory for simulations, but it still should be confirmed during in vivo tests.


Assuntos
Sangue , Técnicas In Vitro , Algoritmos , Coração Auxiliar
17.
Sci Transl Med ; 12(557)2020 08 19.
Artigo em Inglês | MEDLINE | ID: covidwho-694565

RESUMO

Pathogenic coronaviruses are a major threat to global public health, as exemplified by severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and the newly emerged SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19). We describe herein the structure-guided optimization of a series of inhibitors of the coronavirus 3C-like protease (3CLpro), an enzyme essential for viral replication. The optimized compounds were effective against several human coronaviruses including MERS-CoV, SARS-CoV, and SARS-CoV-2 in an enzyme assay and in cell-based assays using Huh-7 and Vero E6 cell lines. Two selected compounds showed antiviral effects against SARS-CoV-2 in cultured primary human airway epithelial cells. In a mouse model of MERS-CoV infection, administration of a lead compound 1 day after virus infection increased survival from 0 to 100% and reduced lung viral titers and lung histopathology. These results suggest that this series of compounds has the potential to be developed further as antiviral drugs against human coronaviruses.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/química , Betacoronavirus/fisiologia , Linhagem Celular , Chlorocebus aethiops , Infecções por Coronavirus/patologia , Cristalografia por Raios X , Cisteína Endopeptidases/química , Modelos Animais de Doenças , Humanos , Técnicas In Vitro , Pulmão/patologia , Pulmão/virologia , Masculino , Camundongos , Camundongos Transgênicos , Testes de Sensibilidade Microbiana , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Modelos Moleculares , Pandemias , Inibidores de Proteases/química , Bibliotecas de Moléculas Pequenas , Especificidade da Espécie , Eletricidade Estática , Pesquisa Médica Translacional , Células Vero , Carga Viral/efeitos dos fármacos , Proteínas não Estruturais Virais/química
18.
Cardiol Rev ; 28(5): 266-271, 2020.
Artigo em Inglês | MEDLINE | ID: covidwho-707022

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to be a threat to the health of many humans across the world as they confront coronavirus disease 2019 (COVID-19). Previous promising in vitro data that emerged after the SARS-CoV outbreak in 2003, along with the emergent need for pharmacologic management strategies in the fight against COVID-19, prompted interest in the use of chloroquine and hydroxychloroquine across the globe. Unfortunately, the in vitro activity of these drugs did not necessarily correlate with most in vivo studies, which showed no consistent efficacy. Safety is also a major concern, with these agents having a known risk of QT prolongation and proarrhythmic effects. In addition, clinical practice guidelines provide no clear consensus on the role of chloroquine or hydroxychloroquine for the management of COVID-19. The United States Food and Drug Administration has declared that the potential benefits of these agents no longer outweigh the possible risks, and unless new emerging information suggests a more favorable risk:benefit ratio, neither chloroquine nor hydroxychloroquine should be recommended for COVID-19 treatment or prevention at this time.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Cloroquina/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Hidroxicloroquina/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Betacoronavirus , Citocromo P-450 CYP2D6/metabolismo , Interações Medicamentosas , Humanos , Técnicas In Vitro , Síndrome do QT Longo/induzido quimicamente , Pandemias , Guias de Prática Clínica como Assunto , Torsades de Pointes/induzido quimicamente , Resultado do Tratamento
19.
PLoS One ; 15(8): e0235102, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857764

RESUMO

Inosine is ubiquitous and essential in many biological processes, including RNA-editing. In addition, oxidative stress on RNA has been a topic of increasing interest due, in part, to its potential role in the development/progression of disease. In this work we probed the ability of three reverse transcriptases (RTs) to catalyze the synthesis of cDNA in the presence of RNA templates containing inosine (I), 8-oxo-7,8-dihydroinosine (8oxo-I), guanosine (G), or 8-oxo-7,8-dihydroguanosine (8-oxoG), and explored the impact that these purine derivatives have as a function of position. To this end, we used 29-mers of RNA (as template) containing the modifications at position-18 and reverse transcribed DNA using 17-mers, 18-mers, or 19-mers (as primers). Generally reactivity of the viral RTs, AMV / HIV / MMLV, towards cDNA synthesis was similar for templates containing G or I as well as for those with 8-oxoG or 8-oxoI. Notable differences are: 1) the use of 18-mers of DNA (to explore cDNA synthesis past the lesion/modification) led to inhibition of DNA elongation in cases where a G:dA wobble pair was present, while the presence of I, 8-oxoI, or 8-oxoG led to full synthesis of the corresponding cDNA, with the latter two displaying a more efficient process; 2) HIV RT is more sensitive to modified base pairs in the vicinity of cDNA synthesis; and 3) the presence of a modification two positions away from transcription initiation has an adverse impact on the overall process. Steady-state kinetics were established using AMV RT to determine substrate specificities towards canonical dNTPs (N = G, C, T, A). Overall we found evidence that RNA templates containing inosine are likely to incorporate dC > dT > > dA, where reactivity in the presence of dA was found to be pH dependent (process abolished at pH 7.3); and that the absence of the C2-exocyclic amine, as displayed with templates containing 8-oxoI, leads to increased selectivity towards incorporation of dA over dC. The data will be useful in assessing the impact that the presence of inosine and/or oxidatively generated lesions have on viral processes and adds to previous reports where I codes exclusively like G. Similar results were obtained upon comparison of AMV and MMLV RTs.


Assuntos
Vírus da Mieloblastose Aviária/enzimologia , Transcriptase Reversa do HIV/metabolismo , Vírus da Leucemia Murina de Moloney/enzimologia , DNA Polimerase Dirigida por RNA/metabolismo , Animais , Sequência de Bases , DNA Complementar/biossíntese , DNA Complementar/química , DNA Complementar/genética , Guanosina/análogos & derivados , Guanosina/química , Guanosina/metabolismo , Humanos , Técnicas In Vitro , Inosina/análogos & derivados , Inosina/química , Inosina/metabolismo , Cinética , Camundongos , RNA Viral/química , RNA Viral/genética , RNA Viral/metabolismo , Moldes Genéticos
20.
J Oleo Sci ; 69(9): 1087-1093, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32788522

RESUMO

Previously, we reported that the polar lipid fraction from the golden oyster mushroom, Pleurotus citrinopileatus, suppresses colon injuries which result from apoptosis induced by inflammatory stresses in vivo and in vitro (Yamashita et al., J. Oleo Sci., 69, 751-757 (2020)). Here, we investigated the use of lipid classes in mushroom polar lipid fraction in alleviating colon injury using differentiated Caco-2 cells as an intestinal tract model. The mushroom polar lipid fraction was separated into four fractions using silica thin layer chromatography. Each mushroom polar lipid fraction suppressed lipopolysaccharide (LPS)-induced decreases in the viability of intestinal cells, and the effects of sphingolipid fractions were significantly stronger than those of fraction that did not contain sphingolipids. Addition of sphingolipid fractions suppressed the expression of apoptosis-related proteins (e.g., death receptors and caspases) in the LPS-treated cells. Mushroom polar lipids, especially sphingolipids suppress intestinal apoptosis induced by inflammatory stress, and highly polar sphingolipids may exert stronger suppressive effects.


Assuntos
Apoptose/efeitos dos fármacos , Doenças do Colo/tratamento farmacológico , Doenças do Colo/patologia , Fitoterapia , Pleurotus/química , Esfingolipídeos/isolamento & purificação , Esfingolipídeos/farmacologia , Apoptose/genética , Células CACO-2 , Caspases/genética , Caspases/metabolismo , Fracionamento Químico , Doenças do Colo/induzido quimicamente , Expressão Gênica , Humanos , Técnicas In Vitro , Inflamação , Lipopolissacarídeos , Esfingolipídeos/uso terapêutico
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