Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Cell ; 184(23): 5699-5714.e11, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34735795

RESUMO

Extension of the interval between vaccine doses for the BNT162b2 mRNA vaccine was introduced in the United Kingdom to accelerate population coverage with a single dose. At this time, trial data were lacking, and we addressed this in a study of United Kingdom healthcare workers. The first vaccine dose induced protection from infection from the circulating alpha (B.1.1.7) variant over several weeks. In a substudy of 589 individuals, we show that this single dose induces severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibody (NAb) responses and a sustained B and T cell response to the spike protein. NAb levels were higher after the extended dosing interval (6-14 weeks) compared with the conventional 3- to 4-week regimen, accompanied by enrichment of CD4+ T cells expressing interleukin-2 (IL-2). Prior SARS-CoV-2 infection amplified and accelerated the response. These data on dynamic cellular and humoral responses indicate that extension of the dosing interval is an effective immunogenic protocol.


Assuntos
Vacinas contra COVID-19/imunologia , Vacinas Sintéticas/imunologia , Adulto , Idoso , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacina BNT162 , COVID-19/sangue , COVID-19/imunologia , COVID-19/virologia , Apresentação Cruzada/imunologia , Relação Dose-Resposta Imunológica , Etnicidade , Feminino , Humanos , Imunidade , Imunoglobulina G/imunologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Padrões de Referência , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Resultado do Tratamento , Adulto Jovem , Vacinas de mRNA
2.
IEEE J Transl Eng Health Med ; 8: 0700210, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670675

RESUMO

Novel myoelectric control strategies may yield more robust, capable prostheses which improve quality of life for those affected by upper-limb loss; however, the development and translation of such strategies from an experimental setting towards daily use by persons with limb loss is a slow and costly process. Since prosthesis functionality is highly dependent on the physical interface between the user's prosthetic socket and residual limb, assessment of such controllers under realistic (noisy) environmental conditions, integrated into prosthetic sockets, and with participants with amputation is essential for obtaining representative results. Unfortunately, this step is particularly difficult as participant- and control strategy-specific prosthetic sockets must be custom-designed and manufactured. There is thus a need for a system to reduce these burdens and facilitate this crucial phase of the development pipeline. This study aims to address this gap through the design and assessment of an inexpensive and easy-to-use 3D-printed Modular-Adjustable transhumeral Prosthetic Socket (MAPS). This 3D-printed, open-source socket was developed in consultation with prosthetists and compared with a participant-specific suction socket in a single-participant case-study. We conducted mechanical and functional assessments to ensure that the developed socket enabled similar performance compared to participant-specific sockets. Both socket systems yielded similar results in mechanical and functional assessments, as well as in self-reported user feedback. The MAPS system shows promise as a research tool which catalyzes the development and deployment of novel myoelectric control strategies by better-enabling comprehensive assessment involving participants with amputations.

3.
Biochem J ; 476(15): 2255-2269, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31350330

RESUMO

Cancerous inhibitor of protein phosphatase 2A (CIP2A) is an adverse biomarker across many malignancies. Using K562 cells engineered to have high or low CIP2A expression, we show that high CIP2A levels significantly bias cellular energy production towards oxidative phosphorylation (OXPHOS) rather than glycolysis. Mass spectrometric analysis of CIP2A interactors and isobaric tagging for relative and absolute protein quantitation (ITRAQ) experiments identified many associated proteins, several of which co-vary with CIP2A level. Many of these CIP2A associating and co-varying proteins are involved in energy metabolism including OXPHOS, or in 5' AMP-activated protein kinase (AMPK) signalling, and manipulating AMPK activity mimics the effects of low/high CIP2A on OXPHOS. These effects are dependent on the availability of nutrients, driven by metabolic changes caused by CIP2A. CIP2A level did not affect starvation-induced AMPK phosphorylation of Unc-51 autophagy activating kinase 1 (ULK-1) at Ser555, but autophagy activity correlated with an increase in AMPK activity, to suggest that some AMPK processes are uncoupled by CIP2A, likely via its inhibition of protein phosphatase 2A (PP2A). The data demonstrate that AMPK mediates this novel CIP2A effect on energy generation in malignant cells.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autoantígenos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Fosforilação Oxidativa , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/genética , Animais , Autoantígenos/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Células K562 , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neoplasias/enzimologia , Neoplasias/genética , Neoplasias/patologia , Smegmamorpha
4.
Anal Chem ; 88(23): 11542-11550, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27801575

RESUMO

The complexity of heparin and heparan sulfate saccharides makes their purification, including many isomeric structures, very challenging and is a bottleneck for structure-activity studies. High-resolution separations have been achieved by strong anion exchange (SAX) chromatography on Propac PA1 and cetyltrimethylammonium (CTA)-C18 silica columns; however, these entail subsequent desalting methodologies and consequent sample losses and are incompatible with orthogonal chromatography methodologies and, in particular, mass spectrometry. Here, we present the CTA-SAX purification of heparin oligosaccharides using volatile salt (VS) buffer. In VSCTA-SAX, the use of ammonium bicarbonate buffer for elution improves resolution through both weaker dissociation and conformational coordination of the ammonium across the sulfate groups. Using ion mobility mass spectrometry, we demonstrate that isomeric structures have different structural conformations, which makes chromatographic separation achievable. Resolution of such structures is improved compared to standard SAX methods, and in addition, VSCTA-SAX provides an orthogonal method to isolate saccharides with higher purity. Because ammonium bicarbonate is used, the samples can be evaporated rather than desalted, preventing substantial sample loss and allowing more effective subsequent analysis by electrospray mass spectrometry. We conclude that VSCTA-SAX is a powerful new tool that helps address the difficult challenge of heparin/heparan sulfate saccharide separation and will enhance structure-activity studies.


Assuntos
Heparina/química , Oligossacarídeos/isolamento & purificação , Compostos Orgânicos Voláteis/química , Compostos de Cetrimônio/química , Cromatografia por Troca Iônica , Espectrometria de Mobilidade Iônica , Oligossacarídeos/química , Sais/química , Estereoisomerismo
5.
PLoS One ; 9(3): e91456, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24614177

RESUMO

During the 2010-2011 E/V Nautilus exploration of the Levantine basin's sediments at the depth of 300-1300 m, densely patched orange-yellow flocculent mats were observed at various locations along the continental margin of Israel. Cores from the mat and the control locations were collected by remotely operated vehicle system (ROV) operated by the E/V Nautilus team. Microscopic observation and phylogenetic analysis of microbial 16S and 23S rRNA gene sequences indicated the presence of zetaproteobacterial stalk forming Mariprofundus spp.-like prokaryotes in the mats. Bacterial tag-encoded FLX amplicon pyrosequencing determined that zetaproteobacterial populations were a dominant fraction of microbial community in the biofilm. We show for the first time that zetaproteobacterial may thrive at the continental margins, regardless of crustal iron supply, indicating significant fluxes of ferrous iron to the sediment-water interface. In light of this discovery, we discuss the potential bioavailability of sediment-water interface iron for organisms in the overlying water column.


Assuntos
Ferro/metabolismo , Proteobactérias/metabolismo , Biofilmes , Geografia , Sedimentos Geológicos/microbiologia , Israel , Dados de Sequência Molecular , Oxirredução , Filogenia , RNA Ribossômico 16S/genética , Tecnologia de Sensoriamento Remoto , Análise de Sequência de DNA , Água
6.
Proc Natl Acad Sci U S A ; 111(11): 4309-14, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24591609

RESUMO

Over the last two decades many secrets of the age-related human neural proteinopathies have been revealed. A common feature of these diseases is abnormal, and possibly pathogenic, aggregation of specific proteins in the effected tissue often resulting from inherent or decreased structural stability. An archetype example of this is superoxide dismutase-1, the first genetic factor to be linked with amyotrophic lateral sclerosis (ALS). Mutant or posttranslationally modified TAR DNA binding protein-32 (TDP-43) is also strongly associated with ALS and an increasingly large number of other neurodegenerative diseases, including frontotemporal lobar degeneration (FTLD). Cytoplasmic mislocalization and elevated half-life is a characteristic of mutant TDP-43. Furthermore, patient age at the onset of disease symptoms shows a good inverse correlation with mutant TDP-43 half-life. Here we show that ALS and FTLD-associated TDP-43 mutations in the central nucleic acid binding domains lead to elevated half-life and this is commensurate with increased thermal stability and inhibition of aggregation. It is achieved without impact on secondary, tertiary, or quaternary structure. We propose that tighter structural cohesion contributes to reduced protein turnover, increasingly abnormal proteostasis and, ultimately, faster onset of disease symptoms. These results contrast our perception of neurodegenerative diseases as misfolded proteinopathies and delineate a novel path from the molecular characteristics of mutant TDP-43 to aberrant cellular effects and patient phenotype.


Assuntos
Proteínas de Ligação a DNA/genética , Doenças Neurodegenerativas/epidemiologia , Doenças Neurodegenerativas/genética , Fluorescência , Meia-Vida , Humanos , Mutação/genética , Doenças Neurodegenerativas/fisiopatologia , Estabilidade Proteica , Espalhamento a Baixo Ângulo
7.
FEMS Microbiol Ecol ; 87(3): 780-96, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24283503

RESUMO

During the 2011 exploration season of the EV Nautilus in the Mediterranean Sea, we conducted a multidisciplinary study, aimed at exploring the microbial populations below the sediment-water interface (SWI) in the hydrocarbon-rich environments of the Levantine basin. Two c. 1000-m-deep locations were sampled: sediments fueled by methane seepage at the toe of the Palmachim disturbance and a patch of euxinic sediment with high sulfide and methane content offshore Acre, enriched by hydrocarbon from an unknown source. We describe the composition of the microbial population in the top 5 cm of the sediment with 1 cm resolution, accompanied by measurements of methane and sulfate concentrations, and the isotopic composition of this methane and sulfate (δ¹³C(CH4), δ¹8O(SO4), and δ³4S(SO4)). Our geochemical and microbiological results indicate the presence of the anaerobic methane oxidation (AOM) coupled to bacterial sulfate reduction (BSR). We show that complex methane and sulfur metabolizing microbial populations are present in both locations, although their community structure and metabolic preferences differ due to potential variation in the hydrocarbon source.


Assuntos
Sedimentos Geológicos/microbiologia , Metano/metabolismo , Sulfatos/metabolismo , Archaea/classificação , Archaea/metabolismo , Bactérias/classificação , Bactérias/metabolismo , Isótopos de Carbono/análise , DNA Arqueal/genética , DNA Bacteriano/genética , Sedimentos Geológicos/química , Mar Mediterrâneo , Oxirredução , Isótopos de Oxigênio/análise , Filogenia , Isótopos de Enxofre/análise
8.
Science ; 329(5988): 207-10, 2010 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-20616276

RESUMO

Styles of subduction zone deformation and earthquake rupture dynamics are strongly linked, jointly influencing hazard potential. Seismic reflection profiles across the trench west of Sumatra, Indonesia, show differences across the boundary between the major 2004 and 2005 plate interface earthquakes, which exhibited contrasting earthquake rupture and tsunami generation. In the southern part of the 2004 rupture, we interpret a negative-polarity sedimentary reflector approximately 500 meters above the subducting oceanic basement as the seaward extension of the plate interface. This predécollement reflector corresponds to unusual prism structure, morphology, and seismogenic behavior that are absent along the 2005 rupture zone. Although margins like the 2004 rupture zone are globally rare, our results suggest that sediment properties influence earthquake rupture, tsunami hazard, and prism development at subducting plate boundaries.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...