741 resultados para strain difference
Resumo:
Purpose: To assess geographical differences within Switzerland regarding management and revascularization procedures for acute myocardial infarction (AMI). Methods: Swiss hospital discharge database for period 2007-2008. The main inclusion criterion was AMI as a primary discharge diagnosis. AMI revascularization procedures were identified and seven Swiss regions (Leman, Mittelland, Northwest, Zurich, Central, Eastern and Ticino) were analyzed. Results: Data from 25,674 AMI discharges were analyzed. Almost half (53.6%) of them were managed in a single hospital, the values ranging from 63.1% (Leman) to 31.4% (Ticino) see table. Relative to the total number of discharges, the highest Intensive Care Unit admission rate was in Leman (69.7%), the lowest (16.4%) in Ticino (Swiss average: 35.8%). Intracoronary revascularization rates were highest in Leman (51.6%) and lowest (30.8%) in Central Switzerland (Swiss average: 41.4%). Bare (non-drug-eluting) stents use was highest in Leman (33.1%) and lowest (7.0%) in Ticino (Swiss average: 15.8%), while drug eluting stent use was highest (32.8%) in Ticino and lowest (13.9%) in Central Switzerland (Swiss average: 24.0%). Coronary artery bypass graft rates were highest (4.6%) in Ticino and lowest (0.4%) in Eastern Switzerland (Swiss average: 2.6%). Mechanical circulatory assistance rates were highest (4.1%) in Zurich and lowest (0.4%) in Ticino (Swiss average: 1.7%). The differences in revascularization procedures remained after adjusting for age, single or multiple hospital management and gender. Conclusion: In Switzerland, significant geographical differences in management and revascularization procedures for AMI were found.
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We study the existence of periodic solutions of the non--autonomous periodic Lyness' recurrence u_{n+2}=(a_n+u_{n+1})/u_n, where {a_n} is a cycle with positive values a,b and with positive initial conditions. It is known that for a=b=1 all the sequences generated by this recurrence are 5-periodic. We prove that for each pair (a,b) different from (1,1) there are infinitely many initial conditions giving rise to periodic sequences, and that the family of recurrences have almost all the even periods. If a is not equal to b, then any odd period, except 1, appears.
Resumo:
Aging is associated with an increased risk of depression in humans. To elucidate the underlying mechanisms of depression and its dependence on aging, here we study signs of depression in male SAMP8 mice. For this purpose, we used the forced swimming test (FST). The total floating time in the FST was greater in SAMP8 than in SAMR1 mice at 9 months of age; however, this difference was not observed in 12-month-old mice, when both strains are considered elderly. Of the two strains, only the SAMP8 animals responded to imipramine treatment. We also applied the dexamethasone suppression test (DST) and studied changes in the dopamine and serotonin (5-HT) uptake systems, the 5-HT2a/2c receptor density in the cortex, and levels of TPH2. The DST showed a significant difference between SAMR1 and SAMP8 mice at old age. SAMP8 exhibits an increase in 5-HT transporter density, with slight changes in 5-HT2a/2c receptor density. In conclusion, SAMP8 mice presented depression-like behavior that is dependent on senescence process, because it differs from SAMR1, senescence resistant strain.
Resumo:
The effects of farm equipment on the structural behavior of flexible and rigid pavements were investigated in this study. The project quantified the difference in pavement behavior caused by heavy farm equipment as compared to a typical 5-axle, 80 kip semi-truck. This research was conducted on full scale pavement test sections designed and constructed at the Minnesota Road Research facility (MnROAD). The testing was conducted in the spring and fall seasons to capture responses when the pavement is at its weakest state and when agricultural vehicles operate at a higher frequency, respectively. The flexible pavement sections were heavily instrumented with strain gauges and earth pressure cells to measure essential pavement responses under heavy agricultural vehicles, whereas the rigid pavement sections were instrumented with strain gauges and linear variable differential transducers (LVDTs). The full scale testing data collected in this study were used to validate and calibrate analytical models used to predict relative damage to pavements. The developed procedure uses various inputs (including axle weight, tire footprint, pavement structure, material characteristics, and climatic information) to determine the critical pavement responses (strains and deflections). An analysis was performed to determine the damage caused by various types of vehicles to the roadway when there is a need to move large amounts agricultural product.
Resumo:
Peroxisome proliferator-activated receptor (PPAR) alpha is a nuclear receptor that is mainly expressed in tissues with a high degree of fatty acid oxidation such as liver, heart, and skeletal muscle. Unsaturated fatty acids, their derivatives, and fibrates activate PPARalpha. Male rats are more responsive to fibrates than female rats. We therefore wanted to investigate if there is a sex difference in PPARalpha expression. Male rats had higher levels of hepatic PPARalpha mRNA and protein than female rats. Fasting increased hepatic PPARalpha mRNA levels to a similar degree in both sexes. Gonadectomy of male rats decreased PPARalpha mRNA expression to similar levels as in intact and gonadectomized female rats. Hypophysectomy increased hepatic PPARalpha mRNA and protein levels. The increase in PPARalpha mRNA after hypophysectomy was more pronounced in females than in males. GH treatment decreased PPARalpha mRNA and protein levels, but the sex-differentiated secretory pattern of GH does not determine the sex-differentiated expression of PPARalpha. The expression of PPARalpha mRNA in heart or soleus muscle was not influenced by gender, gonadectomy, hypophysectomy, or GH treatment. In summary, pituitary-dependent hormones specifically regulate hepatic PPARalpha expression. Sex hormones regulate the sex difference in hepatic PPARalpha levels, but not via the sexually dimorphic GH secretory pattern.
Resumo:
The objective of this study was to characterize weapon-carrying adolescents and to assess whether weapon carriers differ from weapon users. Data were drawn from a cross-sectional school-based survey of 7548 adolescents aged 16-20 years in Switzerland. Youths carrying a weapon were compared with those who do not. Subsequently, weapon carriers were divided into those who had used it in a fight and those who had not. Individual, family, school and social factors were analyzed using bivariate and stepwise multivariate analysis. For both genders, delinquent behavior and being victim of physical violence were associated with weapon carrying. For males, quarreling while intoxicated, being an apprentice, being sensation seekers, having a tattoo, having a poor relationship with parents and practicing unsafe sex were also related to weapon carrying. Compared with weapon carriers, female weapon users were more likely to be regular smokers. Male weapon users were foreign born, urban and apprentices; had poor school connectedness; practiced unsafe sex and quarreled while intoxicated. Carrying a weapon is a relatively frequent behavior among youths in Switzerland and a sizeable proportion of weapon carriers have used it in a fight. Weapon carrying should be part of the clinical assessment and preventive counseling of adolescents. Preventive programs specific for at-risk youth groups need to be developed.
Resumo:
Aging is associated with an increased risk of depression in humans. To elucidate the underlying mechanisms of depression and its dependence on aging, here we study signs of depression in male SAMP8 mice. For this purpose, we used the forced swimming test (FST). The total floating time in the FST was greater in SAMP8 than in SAMR1 mice at 9 months of age; however, this difference was not observed in 12-month-old mice, when both strains are considered elderly. Of the two strains, only the SAMP8 animals responded to imipramine treatment. We also applied the dexamethasone suppression test (DST) and studied changes in the dopamine and serotonin (5-HT) uptake systems, the 5-HT2a/2c receptor density in the cortex, and levels of TPH2. The DST showed a significant difference between SAMR1 and SAMP8 mice at old age. SAMP8 exhibits an increase in 5-HT transporter density, with slight changes in 5-HT2a/2c receptor density. In conclusion, SAMP8 mice presented depression-like behavior that is dependent on senescence process, because it differs from SAMR1, senescence resistant strain.
Resumo:
Aging is associated with an increased risk of depression in humans. To elucidate the underlying mechanisms of depression and its dependence on aging, here we study signs of depression in male SAMP8 mice. For this purpose, we used the forced swimming test (FST). The total floating time in the FST was greater in SAMP8 than in SAMR1 mice at 9 months of age; however, this difference was not observed in 12-month-old mice, when both strains are considered elderly. Of the two strains, only the SAMP8 animals responded to imipramine treatment. We also applied the dexamethasone suppression test (DST) and studied changes in the dopamine and serotonin (5-HT) uptake systems, the 5-HT2a/2c receptor density in the cortex, and levels of TPH2. The DST showed a significant difference between SAMR1 and SAMP8 mice at old age. SAMP8 exhibits an increase in 5-HT transporter density, with slight changes in 5-HT2a/2c receptor density. In conclusion, SAMP8 mice presented depression-like behavior that is dependent on senescence process, because it differs from SAMR1, senescence resistant strain.
Resumo:
Non-target effects of biocontrol strains of Pseudomonas on the population of resident pseudomonads should be assessed prior to their large scale application in the environment. The rifampicin resistant bacterium P. fluorescens CHA0-Rif and its antibiotic overproducing derivative CHA0-Rif/pME3424 were introduced into soil microcosms and the population of resident pseudomonads colonizing cucumber roots was investigated after 10 and 52 days. Both CHA0-Rif and CHA0-Rif/pME3424 displaced a part of the resident pseudomonad population after 10 days. To investigate the population structure, utilization of 10 carbon sources and production of two exoenzymes was assessed for 5600 individual pseudomonad isolates and 1700 isolates were subjected to amplified ribosomal DNA restriction analysis of the spacer region (spacer-ARDRA). After 10 days, only the proportion of pseudomonads able to degrade -tryptophan was reduced in treatments inoculated with either biocontrol strain. In parallel the phenotypic diversity was reduced. These effects were only observed 10 days after inoculation, and they were similar for inoculation with CHA0-Rif and CHA0-Rif/pME3424. Changes in the population structure of resident pseudomonads on cucumber roots during plant growth were more pronounced than changes due to the inoculants. The inoculants did not affect the genotypic diversity detected with spacer-ARDRA, but the genotypic fingerprints corresponded only partially to the phenotypic profiles. Overall CHA0-Rif had a small and transient impact on the population of resident pseudomonads and the effect was essentially the same for the genetically engineered derivative CHA0-
Resumo:
We introduce a set of sequential integro-difference equations to analyze the dynamics of two interacting species. Firstly, we derive the speed of the fronts when a species invades a space previously occupied by a second species, and check its validity by means of numerical random-walk simulations. As an example, we consider the Neolithic transition: the predictions of the model are consistent with the archaeological data for the front speed, provided that the interaction parameter is low enough. Secondly, an equation for the coexistence time between the invasive and the invaded populations is obtained for the first time. It agrees well with the simulations, is consistent with observations of the Neolithic transition, and makes it possible to estimate the value of the interaction parameter between the incoming and the indigenous populations
Resumo:
Aging is associated with an increased risk of depression in humans. To elucidate the underlying mechanisms of depression and its dependence on aging, here we study signs of depression in male SAMP8 mice. For this purpose, we used the forced swimming test (FST). The total floating time in the FST was greater in SAMP8 than in SAMR1 mice at 9 months of age; however, this difference was not observed in 12-month-old mice, when both strains are considered elderly. Of the two strains, only the SAMP8 animals responded to imipramine treatment. We also applied the dexamethasone suppression test (DST) and studied changes in the dopamine and serotonin (5-HT) uptake systems, the 5-HT2a/2c receptor density in the cortex, and levels of TPH2. The DST showed a significant difference between SAMR1 and SAMP8 mice at old age. SAMP8 exhibits an increase in 5-HT transporter density, with slight changes in 5-HT2a/2c receptor density. In conclusion, SAMP8 mice presented depression-like behavior that is dependent on senescence process, because it differs from SAMR1, senescence resistant strain.
Resumo:
We present a model for mechanical activation of the cardiac tissue depending on the evolution of the transmembrane electrical potential and certain gating/ionic variables that are available in most of electrophysiological descriptions of the cardiac membrane. The basic idea consists in adding to the chosen ionic model one ordinary differential equation for the kinetics of the mechanical activation function. A relevant example illustrates the desired properties of the proposed model, such as delayed muscle contraction and correct magnitude of the muscle fibers' shortening.
Resumo:
The vascular properties of large vessels in the obese have not been adequately studied. We used cardiovascular magnetic resonance imaging to quantify the cross-sectional area and elastic properties of the ascending thoracic and abdominal aorta in 21 clinically healthy obese young adult men and 25 men who were age-matched lean controls. Obese subjects had greater maximal cross-sectional area of the ascending thoracic aorta (984 +/- 252 vs 786 +/- 109 mm(2), p <0.01) and of the abdominal aorta (415 +/- 71 vs 374 +/- 51 mm(2), p <0.05). When indexed for height the differences persisted, but when indexed for body surface area, a significant difference between groups was found only for the maximal abdominal aortic cross-sectional area. The obese subjects also had decreased abdominal aortic elasticity, characterized by 24% lower compliance (0.0017 +/- 0.0004 vs 0.0021 +/- 0.0005 mm(2)/kPa/mm, p <0.01), 22% higher stiffness index beta (6.0 +/- 1.5 vs 4.9 +/- 0.7, p <0.005), and 41% greater pressure-strain elastic modulus (72 +/- 25 vs 51 +/- 9, p <0.005). At the ascending thoracic aorta, only the pressure-strain elastic modulus was different between obese and lean subjects (85 +/- 42 vs 65 +/- 26 kPa, respectively; p <0.05), corresponding to a 31% difference-but arterial compliance and stiffness index were not significantly different between groups. In clinically healthy young adult obese men, obesity is associated with increased cross-sectional aortic area and decreased aortic elasticity.
Resumo:
The cellular FLICE inhibitory protein (c-FLIP) is an endogenous inhibitor of the caspase-8 proapoptotic signaling pathway downstream of death receptors. Recent evidence indicates that the long form of c-FLIP (c-FLIP(L)) is required for proliferation and effector T-cell development. However, the role of c-FLIP(L) in triggering autoimmunity has not been carefully analyzed. We now report that c-FLIP(L) transgenic (Tg) mice develop splenomegaly, lymphadenopathy, multiorgan infiltration, high titers of auto-antibodies, and proliferative glomerulonephritis with immune complex deposition in a strain-dependent manner. The development of autoimmunity requires CD4(+) T cells and may result from impaired thymic selection. At the molecular level, c-FLIP(L) overexpression inhibits the zeta chain-associated protein tyrosine kinase of 70 kDa (ZAP-70) activation, thus impairing the signaling pathway derived from ZAP-70 required for thymic selection. Therefore, we have identified c-FLIP(L) as a susceptibility factor under the influence of epistatic modifiers for the development of autoimmunity.