927 resultados para Project 2004-028-C : Wayfinding in the Built Environment


Relevância:

100.00% 100.00%

Publicador:

Resumo:

In order to assess the epidemiological potential of the Culicidae species in remaining areas of the Brazilian Atlantic Forest, specimens of this family were collected in wild and anthropic environments. A total of 9,403 adult mosquitoes was collected from May, 2009 to June, 2010. The most prevalent among species collected in the wild environment were Anopheles (Kerteszia) cruzii, the Melanoconion section of Culex (Melanoconion), and Aedes serratus, while the most common in the anthropic site were Coquillettidia chrysonotum/albifera, Culex (Culex) Coronator group, and An. (Ker.) cruzii. Mosquito richness was similar between environments, although the abundance of individuals from different species varied. When comparing diversity patterns between environments, anthropic sites exhibited higher richness and evenness, suggesting that environmental stress increased the number of favorable niches for culicids, promoting diversity. Increased abundance of opportunistic species in the anthropic environment enhances contact with culicids that transmit vector-borne diseases.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The amyloid precursor protein (APP) is a type I transmembrane glycoprotein, which resembles a cell surface receptor, comprising a large ectodomain, a single spanning transmembrane part and a short C-terminal, cytoplasmic domain. It belongs to a conserved gene family, with over 17 members, including also the two mammalian APP homologues proteins APLP1 and APLP2 („amyloid precursor like proteins“). APP is encoded by 19 exons, of which exons 7, 8, and 15 can be alternatively spliced to produce three major protein isoforms APP770, APP751 and APP695, reflecting the number of amino acids. The neuronal APP695 is the only isoform that lacks a Kunitz Protease Inhibitor (KPI) domain in its extracellular portion whereas the two larger, peripheral APP isoforms, contain the 57-amino-acid KPI insert. rnRecently, research effort has suggested that APP metabolism and function is thought to be influenced by homodimerization and that the oligomerization state of APP could also play a role in the pathology of Alzheimer's disease (AD), by regulating its processing and amyloid beta production. Several independent studies have shown that APP can form homodimers within the cell, driven by motifs present in the extracellular domain, as well as in the juxtamembrane (JM) and transmembrane (TM) regions of the molecule, whereby the exact molecular mechanism and the origin of dimer formation remains elusive. Therefore, we focused in our study on the actual subcellular origin of APP homodimerization within the cell, an underlying mechanism, and a possible impact on dimerization properties of its homologue APLP1. Furthermore, we analyzed homodimerization of various APP isoforms, in particular APP695, APP751 and APP770, which differ in the presence of a Kunitz-type protease inhibitor domain (KPI) in the extracellular region. In order to assess the cellular origin of dimerization under different cellular conditions, we established a mammalian cell culture model-system in CHO-K1 (chinese hamster ovary) cells, stably overexpressing human APP, harboring dilysine based organelle sorting motifs at the very C-terminus [KKAA-Endoplasmic Reticulum (ER); KKFF-Golgi]. In this study we show that APP exists as disulfide-bound, SDS-stable dimers, when it was retained in the ER, unlike when it progressed further to the cis-Golgi, due to the KKFF ER exit determinant. These stable APP complexes were isolated from cells, and analyzed by SDS–polyacrylamide gel electrophoresis under non-reducing conditions, whereas strong denaturing and reducing conditions completely converted those dimers to monomers. Our findings suggested that APP homodimer formation starts early in the secretory pathway and that the unique oxidizing environment of the ER likely promotes intermolecular disulfide bond formation between APP molecules. We particularly visualized APP dimerization employing a variety of biochemical experiments and investigated the origin of its generation by using a Bimolecular Fluorescence Complementation (BiFC) approach with split GFP-APP chimeras. Moreover, using N-terminal deletion constructs, we demonstrate that intermolecular disulfide linkage between cysteine residues, exclusively located in the extracellular E1 domain, represents another mechanism of how an APP sub-fraction can dimerize within the cell. Additionally, mutational studies revealed that cysteines at positions 98 and 105, embedded in the conserved loop region within the E1 domain, are critical for interchain disulfide bond formation. Using a pharmacological treatment approach, we show that once generated in the oxidative environment of the ER, APP dimers remain stably associated during transport, reaching the plasma membrane. In addition, we demonstrate that APP isoforms, encompassing the KPI domain, exhibit a strongly reduced ability to form cis-directed dimers in the ER, whereas trans-directed cell aggregation of Drosophila Schneider (S2)-cells was isoform independent, mediating cell-cell contacts. Thus, suggesting that steric properties of KPI-APP might be the cause for weaker cis-interaction in the ER, compared to APP695. Finally, we provide evidence that APP/APLP1 heterointeractions are likewise initiated in the ER, suggesting a similar mechanism for heterodimerization. Therefore, dynamic alterations of APP between monomeric, homodimeric, and possibly heterodimeric status could at least partially explain some of the variety in the physiological functions of APP.rn

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Phenotypes of plants, and thus their ecology and evolution, can be affected by the environmental conditions experienced by their parents, a phenomenon called parental effects or transgenerational plasticity. However, whether such effects are just passive responses or represent a special type of adaptive plasticity remains controversial because of a lack of solid tests of their adaptive significance. Here, we investigated transgenerational effects of different nutrient environments on the productivity, carbon storage and flowering phenology of the perennial plant Plantago lanceolata, and whether these effects are influenced by seasonal variation in the maternal environment. We found that maternal environments significantly affected the offspring phenotype, and that plants consistently produced more biomass and had greater root carbohydrate storage if grown under the same environmental conditions as experienced by their mothers. The observed transgenerational effects were independent of the season in which seeds had matured. We therefore conclude that transgenerational effects on biomass and carbon storage in P. lanceolata are adaptive regardless of the season of seed maturation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: The Enterococcus faecium genogroup, referred to as clonal complex 17 (CC17), seems to possess multiple determinants that increase its ability to survive and cause disease in nosocomial environments. METHODS: Using 53 clinical and geographically diverse US E. faecium isolates dating from 1971 to 1994, we determined the multilocus sequence type; the presence of 16 putative virulence genes (hyl(Efm), esp(Efm), and fms genes); resistance to ampicillin (AMP) and vancomycin (VAN); and high-level resistance to gentamicin and streptomycin. RESULTS: Overall, 16 different sequence types (STs), mostly CC17 isolates, were identified in 9 different regions of the United States. The earliest CC17 isolates were part of an outbreak that occurred in 1982 in Richmond, Virginia. The characteristics of CC17 isolates included increases in resistance to AMP, the presence of hyl(Efm) and esp(Efm), emergence of resistance to VAN, and the presence of at least 13 of 14 fms genes. Eight of 41 of the early isolates with resistance to AMP, however, were not in CC17. CONCLUSIONS: Although not all early US AMP isolates were clonally related, E. faecium CC17 isolates have been circulating in the United States since at least 1982 and appear to have progressively acquired additional virulence and antibiotic resistance determinants, perhaps explaining the recent success of this species in the hospital environment.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Here we explore the role of the interplay between host immune response and epithelial-mesenchymal-transition (EMT)-Type tumor-budding on the outcome of pancreatic adenocarcinoma (PDAC).CD4+, CD8+, and FOXP3+T-cells as well as iNOS+ (M1) and CD163+- macrophages (M2) were assessed on multipunch tissue-microarrays containing 120 well-characterized PDACs, precursor lesions (PanINs) and corresponding normal tissue. Counts were normalized for the percentage of tumor/spot and associated with the clinico-pathological features, including peritumoral (PTB) and intratumoral (ITB) EMT-Type tumor-budding and outcome.Increased FOXP3+T-cell-counts and CD163-macrophages and decreased CD8+T-cell-counts were observed in PDACs compared with normal tissues and PanINs (p < 0.0001). Increased peritumoral FOXP3+T-cell-counts correlated significantly with venous invasion, distant metastasis, R1-status, high-grade ITB, PTB and independently with reduced survival. Increased intratumoral FOXP3+T-cells correlated with lymphatic invasion, N1-stage, PTB and marginally with adverse outcome. High peritumoral CD163-counts correlated with venous invasion, PTB and ITB. High intratumoral CD163-counts correlated with higher T-stage and PTB.PDAC-microenvironment displays a tumor-favoring immune-cell composition especially in the immediate environment of the tumor-buds that promotes further growth and indicates a close interaction of the immune response with the EMT-process. Increased peritumoral FOXP3+T-cell density is identified as an independent adverse prognostic factor in PDAC. Patients with phenotypically aggressive PDACs may profit from targeted immunotherapy against FOXP3.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Climate change and anthropogenic pollution are of increasing concern in remote areas such as Antarctica. The evolutionary adaptation of Antarctic notothenioid fish to the cold and stable Southern Ocean led to a low plasticity of their physiological functions, what may limit their capacity to deal with altered temperature regimes and pollution in the Antarctic environment. Using a biochemical approach, we aimed to assess the hepatic biotransformation capacities of Antarctic fish species by determining (i) the activities of ethoxyresorufin-O-deethylase (EROD) and glutathione-S-transferase (GST), and (ii) the metabolic clearance of benzo(a)pyrene by hepatic S9 supernatants. In addition, we determined the thermal sensitivity of the xenobiotic biotransformation enzymes. We investigated the xenobiotic metabolism of the red-blooded Gobionotothen gibberifrons and Notothenia rossii, the hemoglobin-less Chaenocephalus aceratus and Champsocephalus gunnari, and the rainbow trout Oncorhynchus mykiss as a reference. Our results revealed similar metabolic enzyme activities and metabolic clearance rates between red- and white-blooded Antarctic fish, but significantly lower rates in comparison to rainbow trout. Therefore, bioaccumulation factors for metabolizable lipophilic contaminants may be higher in Antarctic than in temperate fish. Likewise, the thermal adaptive capacities and flexibilities of the EROD and GST activities in Antarctic fish were significantly lower than in rainbow trout. As a consequence, increasing water temperatures in the Southern Ocean will additionally compromise the already low detoxification capacities of Antarctic fish.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The study of obesity and its causes has evolved into one of the most important public health issues in the United States (Office of Disease Prevention and Health Promotion, 2007). Obesity is linked to several chronic conditions, such as cardiovascular disease, diabetes and some cancers (National Center for Chronic Disease Prevention and Health Promotion, 2008b) and the public health concern resides in the present morbidity and mortality associated with obesity and related conditions (National Heart, Lung and Blood Institute, 1998). Furthermore, obesity and its related conditions present economic challenges to employers in terms of medical health care, sick leave, short-term disability and long-term disability benefits utilized by employees (Østbye, Dement, and Krause, 2007). Recently, articles covering intervention programs targeting obesity in the occupational setting have surfaced in the body of scientific literature. The increased interest in this area stems from the fact that employees in the United States spend more time in the work environment than many industrialized nations, including Japan and most of Western Europe (Organisation for Economic Co-operation and Development, 2006). Moreover, scientific literature supports the idea of investing in healthy human capital to promote productivity and output from employees (Berger, Howell, Nicholson, & Sharda, 2003). The time spent in the work environment, the business need for healthy employees, and the public health concern create an opportunity for planning, implementation and analysis of interventions for effectiveness. This paper aims to identify those intervention programs that focus on the occupational setting related to obesity, to analyze the overall effect of diet, physical fitness and behavioral change interventions targeting overweight and obesity in the occupational setting, and to evaluate the details and effectiveness of components, such as, intervention setting, target participant group, content, industry and length of follow up. Once strengths and weaknesses of the interventions are evaluated, ideas will be suggested for implementation in the future.^

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objetivos: este trabajo tiene como objetivo analizar los niveles de actividad fisicas en estudiantes de escuelas secundarias y estudiantes universitarios; estimar su percepción del entorno contruído en relación con la actividad física, y evaluar la relación entre la educación física y el entorno contruído. Metodología: Se aplicó un estudio sociológico trasversal con diseño no experimental. Se completaron el cuestionario internacional de actividad física y el cuestionario de caraterísticas de entorno contruído con una muestra de 1.862 alumnos de escuelas secundarias y universidad en Granada, España. Resultados: los alumnos de la escuela secundaria fueron significativamente más activos que los estudiantes universitarios, quienes alcanzaron niveles insuficientes de actividad física. Sin embargo, consideraron Granada un buen contexto para hacer ejercicio al aire libre. No se encontraron relaciones entre los niveles de actividad física y el entorno contruído. Conclusión: la discrepancia de resultados entre los niveles de actividad física y la percepción del entorno contruído sugieren la necesidad de intervenciones focalizadas en hacer que los jóvenes se den cuenta de las posibilidades que el medio les ofrece para ejercitarse. En consecuencia, el medio puede tener un impacto en la salud al mismo tiempo que los jóvenes aprenden a respetarlo

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objetivos: este trabajo tiene como objetivo analizar los niveles de actividad fisicas en estudiantes de escuelas secundarias y estudiantes universitarios; estimar su percepción del entorno contruído en relación con la actividad física, y evaluar la relación entre la educación física y el entorno contruído. Metodología: Se aplicó un estudio sociológico trasversal con diseño no experimental. Se completaron el cuestionario internacional de actividad física y el cuestionario de caraterísticas de entorno contruído con una muestra de 1.862 alumnos de escuelas secundarias y universidad en Granada, España. Resultados: los alumnos de la escuela secundaria fueron significativamente más activos que los estudiantes universitarios, quienes alcanzaron niveles insuficientes de actividad física. Sin embargo, consideraron Granada un buen contexto para hacer ejercicio al aire libre. No se encontraron relaciones entre los niveles de actividad física y el entorno contruído. Conclusión: la discrepancia de resultados entre los niveles de actividad física y la percepción del entorno contruído sugieren la necesidad de intervenciones focalizadas en hacer que los jóvenes se den cuenta de las posibilidades que el medio les ofrece para ejercitarse. En consecuencia, el medio puede tener un impacto en la salud al mismo tiempo que los jóvenes aprenden a respetarlo

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objetivos: este trabajo tiene como objetivo analizar los niveles de actividad fisicas en estudiantes de escuelas secundarias y estudiantes universitarios; estimar su percepción del entorno contruído en relación con la actividad física, y evaluar la relación entre la educación física y el entorno contruído. Metodología: Se aplicó un estudio sociológico trasversal con diseño no experimental. Se completaron el cuestionario internacional de actividad física y el cuestionario de caraterísticas de entorno contruído con una muestra de 1.862 alumnos de escuelas secundarias y universidad en Granada, España. Resultados: los alumnos de la escuela secundaria fueron significativamente más activos que los estudiantes universitarios, quienes alcanzaron niveles insuficientes de actividad física. Sin embargo, consideraron Granada un buen contexto para hacer ejercicio al aire libre. No se encontraron relaciones entre los niveles de actividad física y el entorno contruído. Conclusión: la discrepancia de resultados entre los niveles de actividad física y la percepción del entorno contruído sugieren la necesidad de intervenciones focalizadas en hacer que los jóvenes se den cuenta de las posibilidades que el medio les ofrece para ejercitarse. En consecuencia, el medio puede tener un impacto en la salud al mismo tiempo que los jóvenes aprenden a respetarlo

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The concentration and isotopic composition of Nd in water and particles collected in the western Mediterranean Sea are studied by two complementary approaches. The first examines local vertical profiles and time series; the second considers the global Nd budget of the whole western Mediterranean Sea. These two approaches are used to quantify the Nd inputs and the dissolved/particulate exchange processes in the water column. Two profiles of Nd in seawater in the Ligurian Sea taken in May and October 1992 show an average epsilon-Nd(0) = -9.6 ± 0.5. Seawater from the Strait of Sicily, representative of the eastern waters flowing into the western basin, is more radiogenic [epsilon-Nd(0) = -7.7 ± 0.6]. Profiles of particulate matter collected in sediment traps in coastal (Gulf of Lions) and offshore (Ligurian Sea) environments are also shown. Particles are enriched in Nd and are more radiogenic near the coast than offshore. Measurements of Nd concentration and epsilon-Nd(0) of external sources to the western Mediterranean Sea compared with the literature data demonstrate that particulate flux of atmospheric Saharan origin are more rich ([Nd] = 38 ± 10 µg/g) and less radiogenic [epsilon-Nd(0) = -13.0 ± 1.0] than riverine particulate discharge ([Nd] = 21.5 ± 4.4 µg/g; epsilon-Nd(0) = -10.1 ± 0.5), allowing to trace Nd particulate inputs in the water column. Nd atmospheric flux appears to be the major source into the whole western basin, although lateral advection of riverine material is the prevailing process in the coastal environment. Offshore, the vertical propagation of an important Saharan dust event has been recorded for two months in sediment traps at 80, 200 and 1000 m. The evolution of the resulting negative epsilon-Nd(0) peak along depth and time shows that the particles reach 200 m on a time scale of one week. For the first time, the Nd budget in the western Mediterranean basin is constrained by both concentrations and isotopic compositions measured in particles and seawater. Surface budget requires a remobilization of 30 ± 20% of particulate Nd input. In deep water, dissolved Nd concentrations are balanced by a scavenging of 10 ± 20% of the sinking particulate flux. On the other hand, the deep isotopic compositions suggest an exchange between 30 ± 20% of the sinking particles and the deep waters. The hypothesis of a non-stationary regime for the surface waters in the Ligurian Sea is also considered.