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1.
Perception ; 51(1): 37-50, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34904869

RESUMO

Face mask is now a common feature in our social environment. Although face covering reduces our ability to recognize other's face identity and facial expressions, little is known about its impact on the formation of first impressions from faces. In two online experiments, we presented unfamiliar faces displaying neutral expressions with and without face masks, and participants rated the perceived approachableness, trustworthiness, attractiveness, and dominance from each face on a 9-point scale. Their anxiety levels were measured by the State-Trait Anxiety Inventory and Social Interaction Anxiety Scale. In comparison with mask-off condition, wearing face masks (mask-on) significantly increased the perceived approachableness and trustworthiness ratings, but showed little impact on increasing attractiveness or decreasing dominance ratings. Furthermore, both trait and state anxiety scores were negatively correlated with approachableness and trustworthiness ratings in both mask-off and mask-on conditions. Social anxiety scores, on the other hand, were negatively correlated with approachableness but not with trustworthiness ratings. It seems that the presence of a face mask can alter our first impressions of strangers. Although the ratings for approachableness, trustworthiness, attractiveness, and dominance were positively correlated, they appeared to be distinct constructs that were differentially influenced by face coverings and participants' anxiety types and levels.


Assuntos
Expressão Facial , Máscaras , Ansiedade , Atitude , Medo , Humanos , Confiança
2.
Sci Rep ; 10(1): 16873, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037303

RESUMO

Tuberculosis (TB) is the leading cause of death due to a single infectious disease. Knowing when a person was infected with Mycobacterium tuberculosis (M.tb) is critical as recent infection is the strongest clinical risk factor for progression to TB disease in immunocompetent individuals. However, time since M.tb infection is challenging to determine in routine clinical practice. To define a biomarker for recent TB exposure, we determined whether gene expression patterns in blood RNA correlated with time since M.tb infection or exposure. First, we found RNA signatures that accurately discriminated early and late time periods after experimental infection in mice and cynomolgus macaques. Next, we found a 6-gene blood RNA signature that identified recently exposed individuals in two independent human cohorts, including adult household contacts of TB cases and adolescents who recently acquired M.tb infection. Our work supports the need for future longitudinal studies of recent TB contacts to determine whether biomarkers of recent infection can provide prognostic information of TB disease risk in individuals and help map recent transmission in communities.


Assuntos
Busca de Comunicante/métodos , Mycobacterium tuberculosis/genética , RNA Bacteriano/sangue , Tuberculose/diagnóstico , Animais , Biomarcadores/sangue , Testes Diagnósticos de Rotina , Expressão Gênica , Humanos , Macaca , Valor Preditivo dos Testes , Risco , Tuberculose/prevenção & controle , Tuberculose/transmissão
3.
Am J Physiol Regul Integr Comp Physiol ; 314(4): R611-R622, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29351418

RESUMO

Moderate anemia is associated with increased mortality and morbidity, including acute kidney injury (AKI), in surgical patients. A red blood cell (RBC)-specific antibody model was utilized to determine whether moderate subacute anemia could result in tissue hypoxia as a potential mechanism of injury. Cardiovascular and hypoxic cellular responses were measured in transgenic mice capable of expressing hypoxia-inducible factor-1α (HIF-1α)/luciferase activity in vivo. Antibody-mediated anemia was associated with mild intravascular hemolysis (6 h) and splenic RBC sequestration ( day 4), resulting in a nadir hemoglobin concentration of 89 ± 13 g/l on day 4. At this time point, renal tissue oxygen tension (PtO2) was decreased in anemic mice relative to controls (13.1 ± 4.3 vs. 20.8 ± 3.7 mmHg, P < 0.001). Renal tissue hypoxia was associated with an increase in HIF/luciferase expression in vivo ( P = 0.04) and a 20-fold relative increase in renal erythropoietin mRNA transcription ( P < 0.001) but no increase in renal blood flow ( P = 0.67). By contrast, brain PtO2 was maintained in anemic mice relative to controls (22.7 ± 5.2 vs. 23.4 ± 9.8 mmHg, P = 0.59) in part because of an increase in internal carotid artery blood flow (80%, P < 0.001) and preserved cerebrovascular reactivity. Despite these adaptive changes, an increase in brain HIF-dependent mRNA levels was observed (erythropoietin: P < 0.001; heme oxygenase-1: P = 0.01), providing evidence for subtle cerebral tissue hypoxia in anemic mice. These data demonstrate that moderate subacute anemia causes significant renal tissue hypoxia, whereas adaptive cerebrovascular responses limit the degree of cerebral tissue hypoxia. Further studies are required to assess whether hypoxia is a mechanism for acute kidney injury associated with anemia.


Assuntos
Injúria Renal Aguda/sangue , Anemia/sangue , Anticorpos Monoclonais , Encéfalo/irrigação sanguínea , Eritrócitos/metabolismo , Hipóxia Encefálica/sangue , Rim/irrigação sanguínea , Oxigênio/sangue , Injúria Renal Aguda/imunologia , Injúria Renal Aguda/patologia , Injúria Renal Aguda/fisiopatologia , Anemia/imunologia , Anemia/patologia , Anemia/fisiopatologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Circulação Cerebrovascular , Modelos Animais de Doenças , Eritrócitos/imunologia , Eritrócitos/patologia , Eritropoetina/genética , Eritropoetina/metabolismo , Glicoforinas/sangue , Glicoforinas/imunologia , Hemólise , Hipóxia Encefálica/imunologia , Hipóxia Encefálica/patologia , Hipóxia Encefálica/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Rim/metabolismo , Rim/patologia , Masculino , Camundongos Transgênicos , Circulação Renal , Índice de Gravidade de Doença , Baço/metabolismo , Baço/patologia , Regulação para Cima
4.
FEMS Microbiol Lett ; 334(1): 57-65, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22697494

RESUMO

In the DNA damage response of most bacteria, UmuD forms part of the error-prone (UmuD'(2) )C polymerase V and is activated for this function by self-cleavage after DNA damage. However, the umuD homolog (umuDAb) present throughout the Acinetobacter genus encodes an extra N-terminal region, and in Acinetobacter baylyi, regulates transcription of DNA damage-induced genes. UmuDAb expressed in cells was correspondingly larger (24 kDa) than the Escherichia coli UmuD (15 kDa). DNA damage from mitomycin C or UV exposure caused UmuDAb cleavage in both E. coli wild-type and ΔumuD cells on a timescale resembling UmuD, but did not require UmuD. Like the self-cleaving serine proteases LexA and UmuD, UmuDAb required RecA for cleavage. This cleavage produced a UmuDAb' fragment of a size consistent with the predicted cleavage site of Ala83-Gly84. Site-directed mutations at Ala83 abolished cleavage, as did mutations at either the Ser119 or Lys156 predicted enzymatic residues. Co-expression of the cleavage site mutant and an enzymatic mutant did not allow cleavage, demonstrating a strictly intramolecular mechanism of cleavage that more closely resembles the LexA-type repressors than UmuD. These data show that UmuDAb undergoes a post-translational, LexA-like cleavage event after DNA damage, possibly to achieve its regulatory action.


Assuntos
Acinetobacter/enzimologia , Acinetobacter/genética , Proteínas de Bactérias/metabolismo , Dano ao DNA , DNA Polimerase Dirigida por DNA/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Serina Endopeptidases/metabolismo , Acinetobacter/efeitos da radiação , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Dano ao DNA/efeitos da radiação , DNA Polimerase Dirigida por DNA/química , DNA Polimerase Dirigida por DNA/genética , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/efeitos da radiação , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Dados de Sequência Molecular , Processamento de Proteína Pós-Traducional , Recombinases Rec A/genética , Recombinases Rec A/metabolismo , Alinhamento de Sequência , Serina Endopeptidases/química , Serina Endopeptidases/genética , Raios Ultravioleta
5.
Environ Sci Technol ; 44(15): 5805-11, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20617840

RESUMO

Twelve marine sediment cores from Hudson Bay, Canada, were collected to investigate the response of sub-Arctic marine sediments to atmospherically transported anthropogenic mercury (Hg). Modeling by a two-layer sediment mixing model suggests that the historical Hg deposition to most of the sediment cores reflects the known history of atmospheric Hg deposition in North America, with an onset of increasing anthropogenic Hg emissions in the late 1800s and early 1900s and a reduction of Hg deposition in the mid- to late-1900s. However, although anthropogenic Hg has contributed to a ubiquitous increase in Hg concentrations in sediments over the industrial era, the most elevated industrial-era sedimentary Hg concentrations only marginally exceed the upper preindustrial sedimentary Hg concentrations. Analysis of delta13C and relationship between Hg and organic matter capture suggests that the response of Hudson Bay sediments to changes in atmospheric Hg emissions is largely controlled by the particle flux in the system and that natural changes in organic matter composition and dynamics can cause variation in sedimentary Hg concentrations at least to the same extent as those caused by increasing anthropogenic Hg emissions.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Mercúrio/análise , Poluentes Químicos da Água/análise , Canadá , Água do Mar/química , Poluição Química da Água/estatística & dados numéricos
6.
Sci Total Environ ; 406(1-2): 190-204, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18765159

RESUMO

Based on extensive sampling of the rivers, troposphere, seawater and sediments, mercury (Hg) mass budgets are constructed for both contemporary and preindustrial times in the Hudson Bay Marine System (HBS) to probe sources and pathways of Hg and their responses to the projected climate change. The contemporary total Hg inventory in the HBS is estimated to be 98 t, about 1% of which is present in the biotic systems and the remainder in the abiotic systems. The total contemporary Hg influx and outflux, around 6.3 t/yr each, represent a 2-fold increase from the preindustrial fluxes. The most notable changes are in the atmospheric flux, which has gone from a nearly neutral (0.1 t/yr) to source term (1.5 t/yr), increased river inputs (which may also reflect increased atmospheric deposition to the HBS watershed) and in the sedimentary burial flux which has increased by 2.4 t/yr over preindustrial values, implying that much of the modern Hg loading entering this system is buried in the sediments. The capacity to drive increased Hg loading from the atmosphere to sediment burial may be supported by the resuspension of an extraordinarily large flux (120 Mt/yr) of shallow water glacigenic sediments uncontaminated by anthropogenic Hg, which could scavenge Hg from the water column before being transported to the deeper accumulative basins. Under the projected climate warming in the region, the rate of the sediment recycling pump will likely increase due to enhanced Hg scavenging by increasing biological productivity, and thus strengthen atmosphere-ocean Hg exchanges in the HBS.


Assuntos
Conservação dos Recursos Naturais , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Mercúrio/análise , Poluentes Químicos da Água/análise , Regiões Árticas , Atmosfera/química , Canadá , Clima , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Geografia , Sedimentos Geológicos/química , Mercúrio/química , Modelos Biológicos , Rios , Água do Mar , Fatores de Tempo , Poluentes Químicos da Água/química
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