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61.
Gunilla Journath Niklas Hammar Stig Elofsson Anette Linnersj? Max Vikstr?m G?ran Walldius Ingvar Krakau Peter Lindgren Ulf de Faire Mai-Lis Hellénius 《PloS one》2015,10(11)
Background
In 1988, a cardiovascular prevention program which combined an individual and a population-based strategy was launched within primary health-care in Sollentuna, a municipality in Stockholm County. The aim of this study was to investigate time trends in the incidence of and mortality from acute myocardial infarction and all-cause mortality in Sollentuna compared with the rest of Stockholm County during a period of two decades following the implementation of a cardiovascular prevention program.Materials and Methods
The average population in Sollentuna was 56,589 (49% men) and in Stockholm County (Sollentuna included) 1,795,504 (49% men) during the study period of 1987–2010. Cases of hospitalized acute myocardial infarction and death were obtained for the population of Sollentuna and the rest of Stockholm County using national registries of hospital discharges and deaths. Acute myocardial infarction incidence and mortality were estimated using the average population of Sollentuna and Stockholm in 1987–2010.Results
During the observation period, the incidence of acute myocardial infarction decreased more in Sollentuna compared with the rest of Stockholm County in women (-22% vs. -7%; for difference in slope <0.05). There was a trend towards a greater decline in Sollentuna compared to the rest of Stockholm County in the incidence of acute myocardial infarction (in men), acute myocardial mortality, and all-cause mortality but the differences were not significant.Conclusion
During a period of steep decline in acute myocardial infarction incidence and mortality in Stockholm County the municipality of Sollentuna showed a stronger trend in women possibly compatible with favorable influence of a cardiovascular prevention program.Trial Registration
ClinicalTrials.gov NCT02212145 相似文献62.
Rodrigo Egydio Barreto Augusto Barbosa-Júnior Elisabeth Criscuolo Urbinati Anette Hoffmann 《Hormones and behavior》2014
We evaluated the effect of increased plasma cortisol levels on fish antipredator behavior induced by conspecific chemical alarm cues. The experimental model for the study was the Frillfin goby Bathygobius soporator. We first confirmed that the alarm substance induces typical defensive antipredator responses in Frillfin gobies and described their alarm substance cells (epidermal ‘club’ cells). Second, we confirmed that intraperitoneal cortisol implants increase plasma cortisol levels in this species. We then demonstrated that exogenous cortisol administration and subsequent exposure to an alarm substance decreased swimming activity to a greater extent than the activity prompted by either stimulus alone. In addition, cortisol did not abolish the sheltering response to the alarm chemical cue even though it decreased activity. As predators use prey movements to guide their first contact with the prey, a factor that decreases swimming activity clearly increases the probability of survival. Consequently, this observation indicates that cortisol helps improve the antipredator response in fish. 相似文献
63.
Experiments were performed to investigate senses that are essential for mediating fright reaction and food behavior in Pseudoplatystoma corruscans, pintado. The dilemma “to feed or to flee” was also analyzed in fishes with intact and sectioned olfactory tracts, stimulated
by alarm substance extracts and food. Fishes were arranged into five groups: fish with intact lateral olfactory tracts (LOT),
fish with intact medial olfactory tract (MOT), fish with tracts totally sectioned (TOTAL, both LOT and MOT), sham operated,
and nonoperated fish. The five groups were submitted to either alarm substance extract and food stimulus or to distilled water
(control) and food stimulus. Fish reacted to food independently of which tract (LOT, MOT or TOTAL) was sectioned; vision seems
necessary and elemental to detect and deflagrate food response. Latency of the responses to each reaction was different between
groups. None of the fish with sectioned tracts reacted to alarm substance extract, while sham- and nonoperated fish showed
the typical alarm behavior response, leading to the conclusion that olfaction is essential for mediating alarm response. These
results indicate that others sense systems (e.g., vision) are sufficient to trigger and elicit feeding behavior and that olfaction
is not necessary to fully maintain food detection to qualitative and quantitative extent. However, olfactory tract integrity
seems to be required for mediation of alarm reaction in P. corruscans. 相似文献
64.
Integrins are cell adhesion receptors that are evolutionary old and that play important roles during developmental and pathological
processes. The integrin family is composed of 24 αβ heterodimeric members that mediate the attachment of cells to the extracellular
matrix (ECM) but that also take part in specialized cell-cell interactions. Only a subset of integrins (8 out of 24) recognizes
the RGD sequence in the native ligands. In some ECM molecules, such as collagen and certain laminin isoforms, the RGD sequences
are exposed upon denaturation or proteolytic cleavage, allowing cells to bind these ligands by using RGD-binding receptors.
Proteolytic cleavage of ECM proteins might also generate fragments with novel biological activity such as endostatin, tumstatin,
and endorepellin. Nine integrin chains contain an αI domain, including the collagen-binding integrins α1β1, α2β1, α10β1, and
α11β1. The collagen-binding integrins recognize the triple-helical GFOGER sequence in the major collagens, but their ability
to recognize these sequences in vivo is dependent on the fibrillar status and accessibility of the interactive domains in
the fibrillar collagens. The current review summarizes some basic facts about the integrin family including a historical perspective,
their structure, and their ligand-binding properties. 相似文献
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Deadenylation is the first and probably also rate-limiting step of controlled mRNA decay in eukaryotes and therefore central for the overall rate of gene expression. In yeast, the process is maintained by the mega-Dalton Ccr4-Not complex, of which both the Ccr4p and Pop2p subunits are 3′–5′ exonucleases potentially responsible for the deadenylation reaction. Here, we present the crystal structure of the Pop2p subunit from Schizosaccharomyces pombe determined to 1.4Å resolution and show that the enzyme is a competent ribonuclease with a tunable specificity towards poly-A. In contrast to S. cerevisiae Pop2p, the S. pombe enzyme contains a fully conserved DEDDh active site, and the high resolution allows for a detailed analysis of its configuration, including divalent metal ion binding. Functional data further indicates that the identity of the ions in the active site can modulate both activity and specificity of the enzyme, and finally structural superposition of single nucleotides and poly-A oligonucleotides provide insight into the catalytic cycle of the protein. 相似文献
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