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1.
J Am Med Inform Assoc ; 28(9): 2009-2012, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34151980

RESUMO

The COVID-19 pandemic has once again highlighted the ubiquity and persistence of health inequities along with our inability to respond to them in a timely and effective manner. There is an opportunity to address the limitations of our current approaches through new models of informatics-enabled research and clinical practice that shift the norm from small- to large-scale patient engagement. We propose augmenting our approach to address health inequities through informatics-enabled citizen science, challenging the types of questions being asked, prioritized, and acted upon. We envision this democratization of informatics that builds upon the inclusive tradition of community-based participatory research (CBPR) as a logical and transformative step toward improving individual, community, and population health in a way that deeply reflects the needs of historically marginalized populations.


Assuntos
Ciência do Cidadão , Pesquisa Participativa Baseada na Comunidade , Equidade em Saúde , Informática , COVID-19 , Humanos , Pandemias
2.
Artigo em Inglês | MEDLINE | ID: mdl-18952494

RESUMO

A range of archaeological samples have been examined using FT-IR spectroscopy. These include suspected coprolite samples from the Neolithic site of Catalhöyük in Turkey, pottery samples from the Roman site of Silchester, UK and the Bronze Age site of Gatas, Spain and unidentified black residues on pottery sherds from the Roman sites of Springhead and Cambourne, UK. For coprolite samples the aim of FT-IR analysis is identification. Identification of coprolites in the field is based on their distinct orange colour; however, such visual identifications can often be misleading due to their similarity with deposits such as ochre and clay. For pottery the aim is to screen those samples that might contain high levels of organic residues which would be suitable for GC-MS analysis. The experiments have shown coprolites to have distinctive spectra, containing strong peaks from calcite, phosphate and quartz; the presence of phosphorus may be confirmed by SEM-EDX analysis. Pottery containing organic residues of plant and animal origin has also been shown to generally display strong phosphate peaks. FT-IR has distinguished between organic resin and non-organic compositions for the black residues, with differences also being seen between organic samples that have the same physical appearance. Further analysis by GC-MS has confirmed the identification of the coprolites through the presence of coprostanol and bile acids, and shows that the majority of organic pottery residues are either fatty acids or mono- or di-acylglycerols from foodstuffs, or triterpenoid resin compounds exposed to high temperatures. One suspected resin sample was shown to contain no organic residues, and it is seen that resin samples with similar physical appearances have different chemical compositions. FT-IR is proposed as a quick and cheap method of screening archaeological samples before subjecting them to the more expensive and time-consuming method of GC-MS. This will eliminate inorganic samples such as clays and ochre from GC-MS analysis, and will screen those samples which are most likely to have a high concentration of preserved organic residues.


Assuntos
Arqueologia , Compostos Orgânicos/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Silicatos de Alumínio/análise , Argila , Cromatografia Gasosa-Espectrometria de Massas , Resinas Sintéticas/análise , Espectrofotometria Infravermelho , Reino Unido
3.
J Appl Physiol (1985) ; 102(3): 1143-51, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17122379

RESUMO

Chronic muscle disuse induced by denervation reduces mitochondrial content and produces muscle atrophy. To investigate the molecular mechanisms responsible for these adaptations, we assessed 1) mitochondrial biogenesis- and apoptosis-related proteins and 2) apoptotic susceptibility and cell death following denervation. Rats were subjected to 5, 7, 14, 21, or 42 days of unilateral denervation of the sciatic or peroneal nerve. Muscle mass and mitochondrial content were reduced by 40-65% after 21 and 42 days of denervation. Denervation-induced decrements in mitochondrial content occurred along with 60% and 70% reductions in transcription factor A (Tfam) and peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha, respectively. After 42 days of denervation, Bax was elevated by 115% and Bcl-2 was decreased by 89%, producing a 16-fold increase in the Bax-to-Bcl-2 ratio. Mitochondrial reactive oxygen species production was markedly elevated by 5- to 7.5-fold in subsarcolemmal mitochondria after 7, 14, and 21 days of denervation, whereas reactive oxygen species production in intermyofibrillar (IMF) mitochondria was reduced by 40-50%. Subsarcolemmal and IMF mitochondrial levels of MnSOD were also reduced by 40-50% after 14-21 days of denervation. The maximal rate of IMF mitochondrial pore opening (V(max)) was elevated by 25-35%, and time to V(max) was reduced by 20-25% after 14 and 21 days, indicating increased apoptotic susceptibility. Myonuclear decay, assessed by DNA fragmentation, was elevated at 7-21 days of denervation. Our data indicate that PGC-1alpha and Tfam are important factors that likely contribute to the reduced mitochondrial content after chronic disuse. In addition, our results illustrate that, despite the reduced mitochondrial content, denervated muscle has greater mitochondrial apoptotic susceptibility, which coincided with elevated apoptosis, and these processes may contribute to denervation-induced muscle atrophy.


Assuntos
Apoptose/fisiologia , Mitocôndrias Musculares/fisiologia , Músculo Esquelético/inervação , Transtornos Musculares Atróficos/fisiopatologia , Adaptação Fisiológica , Animais , Núcleo Celular/metabolismo , Respiração Celular/fisiologia , Expressão Gênica , Marcação In Situ das Extremidades Cortadas , Masculino , Denervação Muscular , Fibras Musculares Esqueléticas/patologia , Proteínas Musculares/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/fisiologia , Atrofia Muscular/patologia , Transtornos Musculares Atróficos/patologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Canais de Ânion Dependentes de Voltagem/metabolismo
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