95 resultados para Cities and suburbs : new metropolitan realities in the US
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BACKGROUND: Epidemiological data for south Asian children in the United Kingdom are contradictory, showing a lower prevalence of wheeze, but a higher rate of medical consultations and admissions for asthma compared with white children. These studies have not distinguished different asthma phenotypes or controlled for varying environmental exposures. OBJECTIVE: To compare the prevalence of wheeze and related health-service use in south Asian and white pre-schoolchildren in the United Kingdom, taking into account wheeze phenotype (viral and multiple wheeze) and environmental exposures. METHODS: A postal questionnaire was completed by parents of a population-based sample of 4366 white and 1714 south Asian children aged 1-4 years in Leicestershire, UK. Children were classified as having viral wheeze or multiple trigger wheeze. RESULTS: The prevalence of current wheeze was 35.6% in white and 25.5% in south Asian 1-year-olds (P<0.001), and 21.9% and 20.9%, respectively, in children aged 2-4 years. Odds ratios (ORs) (95% confidence interval) for multiple wheeze and for viral wheeze, comparing south Asian with white children, were 2.21 (1.19-4.09) and 1.43 (0.77-2.65) in 2-4-year-olds after controlling for socio-economic conditions, environmental exposures and family history. In 1-year-olds, the respective ORs for multiple and viral wheeze were 0.66 (0.47-0.92) and 0.81 (0.64-1.03). Reported GP consultation rates for wheeze and hospital admissions were greater in south Asian children aged 2-4 years, even after adjustment for severity, but the use of inhaled corticosteroids was lower. CONCLUSIONS: South Asian 2-4-year-olds are more likely than white children to have multiple wheeze (a condition with many features of chronic atopic asthma), after taking into account ethnic differences in exposure to some environmental agents. Undertreatment with inhaled corticosteroids might partly explain their greater use of health services.
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Ovariectomy interrupts the regulatory loop in the hypothalamus-pituitary-gonad axis, leading to a several-fold increase in gonadotropin levels. This rise in hormonal secretion may play a causal role in ovariectomy-related urinary incontinence. The purpose of this study was to examine the effect of ovariectomy in bitches on the expression of GnRH- and LH-receptors in the lower urinary tract, and assess the relationship between receptor expression and plasma gonadotropin concentrations. Plasma gonadotropins were measured in 37 client-owned bitches. Biopsies were harvested from the mid-ventral bladder wall in all dogs, and from nine further locations within the lower urinary tract in 17 of the 37 animals. Messenger RNA of the LH and GnRH receptors was quantified using RT-PCR with the TaqMan Universal PCR Master Mix. Gonadotropins were measured with a canine-specific FSH-immunoradiometric assay and LH-radioimmunoassay. The hierarchical mixed ANOVA model using MINITAB, Mann-Whitney U-test, unpaired means comparison and linear regressions using StatView were applied for statistical analyses. Messenger RNA for both receptors was detected in all biopsy samples. Age was negatively correlated to mRNA expression of the LH and the GnRH receptors. A relationship between the mRNA values and the plasma gonadotropin concentrations was not established. Evaluation of results within each of the biopsy locations revealed greater LH-receptor expression in the proximal second quarter of the urethra in spayed bitches than in intact bitches (P=0.0481). Increased mRNA expression of LH receptors in this location could possibly play a role in the decrease in closing pressure of the urethra following ovariectomy.
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ABSTRACT: Nanotechnology in its widest sense seeks to exploit the special biophysical and chemical properties of materials at the nanoscale. While the potential technological, diagnostic or therapeutic applications are promising there is a growing body of evidence that the special technological features of nanoparticulate material are associated with biological effects formerly not attributed to the same materials at a larger particle scale. Therefore, studies that address the potential hazards of nanoparticles on biological systems including human health are required. Due to its large surface area the lung is one of the major sites of interaction with inhaled nanoparticles. One of the great challenges of studying particle-lung interactions is the microscopic visualization of nanoparticles within tissues or single cells both in vivo and in vitro. Once a certain type of nanoparticle can be identified unambiguously using microscopic methods it is desirable to quantify the particle distribution within a cell, an organ or the whole organism. Transmission electron microscopy provides an ideal tool to perform qualitative and quantitative analyses of particle-related structural changes of the respiratory tract, to reveal the localization of nanoparticles within tissues and cells and to investigate the 3D nature of nanoparticle-lung interactions.This article provides information on the applicability, advantages and disadvantages of electron microscopic preparation techniques and several advanced transmission electron microscopic methods including conventional, immuno and energy-filtered electron microscopy as well as electron tomography for the visualization of both model nanoparticles (e.g. polystyrene) and technologically relevant nanoparticles (e.g. titanium dioxide). Furthermore, we highlight possibilities to combine light and electron microscopic techniques in a correlative approach. Finally, we demonstrate a formal quantitative, i.e. stereological approach to analyze the distributions of nanoparticles in tissues and cells.This comprehensive article aims to provide a basis for scientists in nanoparticle research to integrate electron microscopic analyses into their study design and to select the appropriate microscopic strategy.
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Surface exposure dating (SED) is an innovative tool already being widely applied for moraine dating and for Late Quaternary glacier and climate reconstruction. Here we present exposure ages of 28 boulders from the Cordillera Real and the Cordillera Cochabamba, Bolivia. Our results indicate that the local Last Glacial Maximum (LGM) in the Eastern Cordilleras occurred at ~22–25 ka and was thus synchronous to the global temperature minimum. We were also able to date several Late Glacial moraines to ~11–13 ka, which likely document lower temperatures and increased precipitation ("Coipasa" humid phase). Additionally, we recognize the existence of older Late Glacial moraines re-calculated to ~15 ka from published cosmogenic nuclide data. Those may coincide with the cold Heinrich 1 event in the North Atlantic region and the pronounced "Tauca" humid phase. We conclude that (i) exposure ages in the tropical Andes may have been overestimated so far due to methodological uncertainties, and (ii) although precipitation plays an important role for glacier mass balances in the tropical Andes, it becomes the dominant forcing for glaciation only in the drier and thus more precipitation-sensitive regions farther west and south.
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Soft tissue damage has been observed in hip joints with pathological geometries. Our primary goal was to study the relationship between morphological variations of the bony components of the hip and resultant stresses within the soft tissues of the joint during routine daily activities. The secondary goal was to find the range of morphological parameters in which stresses are minimized. Computational models of normal and pathological joints were developed based on variations of morphological parameters of the femoral head (Alpha angle) and acetabulum (CE angle). The Alpha angle was varied between 40 degrees (normal joint) and 80 degrees (cam joint). The CE angle was varied between 0 degrees (dysplastic joint) and 40 degrees (pincer joint). Dynamic loads and motions for walking and standing to sitting were applied to all joint configurations. Contact pressures and stresses were calculated and crosscompared to evaluate the influence of morphology. The stresses in the soft tissues depended strongly on the head and acetabular geometry. For the dysplastic joint, walking produced high acetabular rim stresses. Conversely, for impinging joints, standing-to-sitting activities that involved extensive motion were critical, inducing excessive distortion and shearing of the tissue-bone interface. Zones with high von Mises stresses corresponded with clinically observed damage zones in the acetabular cartilage and labrum. Hip joint morphological parameters that minimized were 20 degrees
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CONTEXT: Magnetic resonance imaging (MRI) combined with magnetic resonance spectroscopy imaging (MRSI) emerged as a promising test in the diagnosis of prostate cancer and showed encouraging results. OBJECTIVE: The aim of this systematic review is to meta-analyse the diagnostic accuracy of combined MRI/MRSI in prostate cancer and to explore risk profiles with highest benefit. EVIDENCE ACQUISITION: The authors searched the MEDLINE and EMBASE databases and the Cochrane Library, and the authors screened reference lists and contacted experts. There were no language restrictions. The last search was performed in August 2008. EVIDENCE SYNTHESIS: We identified 31 test-accuracy studies (1765 patients); 16 studies (17 populations) with a total of 581 patients were suitable for meta-analysis. Nine combined MRI/MRSI studies (10 populations) examining men with pathologically confirmed prostate cancer (297 patients; 1518 specimens) had a pooled sensitivity and specificity on prostate subpart level of 68% (95% CI, 56-78%) and 85% (95% CI, 78-90%), respectively. Compared with patients at high risk for clinically relevant cancer (six studies), sensitivity was lower in low-risk patients (four studies) (58% [46-69%] vs 74% [58-85%]; p>0.05) but higher for specificity (91% [86-94%] vs 78% [70-84%]; p<0.01). Seven studies examining patients with suspected prostate cancer at combined MRI/MRSI (284 patients) had an overall pooled sensitivity and specificity on patients level of 82% (59-94%) and 88% (80-95%). In the low-risk group (five studies) these values were 75% (39-93%) and 91% (77-97%), respectively. CONCLUSIONS: A limited number of small studies suggest that MRI combined with MRSI could be a rule-in test for low-risk patients. This finding needs further confirmation in larger studies and cost-effectiveness needs to be established.
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The transport of lipids across mammary gland epithelial cells (MEC) determines milk lipid content and composition. We investigated the expression of lipid transporters and their regulators in comparison to blood metabolites during lactation and dry period (DP) in dairy cows. Repeated mammary gland biopsies and blood samples were taken from 10 animals at 7 stages of the pregnancy-lactation cycle. Expression levels of the specific mRNAs were determined by quantitative reverse transcription-PCR, whereas ABCA1 was localized by immunohistochemistry. Blood serum metabolites were determined by common enzymatic chemistries. Elevated mRNA profiles of ABCA1 and ABCA7 were found during DP as compared with lactation and were inversely associated with blood cholesterol levels. Elevated levels of ABCG2, NPC1, SREBP1, SREBP2, LXR alpha, and PPAR gamma were found postpartum, whereas ABCG1 did not differ between the functional stages of the mammary gland. The ABCA1 protein was localized in MEC and showed differential activity between DP and lactation suggesting a role of ABCA1 in the removal of excess cellular cholesterol from MEC during the DP. The expression profiles of ABCA7 and NPC1 may reflect a role of these transporters in the clearance of apoptotic cells and the intracellular redistribution of cholesterol, respectively. Regulation of lipid transporters in the mammary gland is partially associated with transcription factors that control lipid homeostasis.
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BACKGROUND: Alcohol consumption leading to morbidity and mortality affects HIV-infected individuals. Here, we aimed to study self-reported alcohol consumption and to determine its association with adherence to antiretroviral therapy (ART) and HIV surrogate markers. METHODS: Cross-sectional data on daily alcohol consumption from August 2005 to August 2007 were analysed and categorized according to the World Health Organization definition (light, moderate or severe health risk). Multivariate logistic regression models and Pearson's chi(2) statistics were used to test the influence of alcohol use on endpoints. RESULTS: Of 6,323 individuals, 52.3% consumed alcohol less than once a week in the past 6 months. Alcohol intake was deemed light in 39.9%, moderate in 5.0% and severe in 2.8%. Higher alcohol consumption was significantly associated with older age, less education, injection drug use, being in a drug maintenance programme, psychiatric treatment, hepatitis C virus coinfection and with a longer time since diagnosis of HIV. Lower alcohol consumption was found in males, non-Caucasians, individuals currently on ART and those with more ART experience. In patients on ART (n=4,519), missed doses and alcohol consumption were positively correlated (P<0.001). Severe alcohol consumers, who were pretreated with ART, were more often off treatment despite having CD4+ T-cell count <200 cells/microl; however, severe alcohol consumption per se did not delay starting ART. In treated individuals, alcohol consumption was not associated with worse HIV surrogate markers. CONCLUSIONS: Higher alcohol consumption in HIV-infected individuals was associated with several psychosocial and demographic factors, non-adherence to ART and, in pretreated individuals, being off treatment despite low CD4+ T-cell counts.
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In the Peruvian Andes, a long history of interaction between the local populations and their natural environment has led to extraordinary levels of agrobiodiversity. However, in sharp contrast with this biological wealth, Andean indigenous populations live under most precarious conditions. Moreover, natural resources are undergoing severe degradation processes and local knowledge about biodiversity management is under serious pressure. Against this background, the BioAndes Programme is developing initiatives based on a biocultural approach that aim at fostering biodiversity through the enhancement of cultural processes. On the basis of intercultural dialogue, joint learning and capacity development, and transdisciplinary action-research, indigenous communities, development practitioners, and researchers strive for the creation of innovative ways to contribute to more sustainable economic, socio-cultural, and political valorization of Andean biodiversity. Project activities are diverse and range from the cultivation, transformation, and commercialization of organic Andean fruits in San Marcos, Cajamarca Department, to the recuperation of natural dying techniques for alpaca wool and traditional weaving in Pitumarca, Cusco Department, and the promotion of responsible ecotourism in both regions. Based on the projects’ first two-years of experience, the following lessons learnt will be presented and discussed: 1. The economic valorization and commercialization of local products can be a powerful tool for the revival and innovation of eroded know-how; at the same time it contributes to the strengthening of local identities, in parallel with the empowerment of marginalized groups such as smallholders and women. 2. Such initiatives are only successful when they are embedded within activities that go beyond the focus on local products and seek the valorization of the entire natural and cultural landscape (e.g. through the promotion of agrotourism and local gastronomy, more sustainable management of local resources including the restoration of ecosystems, and the realization of inventories of local agrobiodiversity and the knowledge related to it). 3. The sustainability of these initiatives, which are often externally induced, is conditioned by the ability of local actors to acquire ownership of projects and access to the knowledge required to carry them out, which also means developing the personal and institutional capacities for handling the whole chain from production to commercialization. 4. The confrontation of different economic rationalities and their underlying worldviews that occur when local or indigenous people integrate into the market economy implies the need for a dialogical co-production of knowledge and collective action by local people, experts from NGOs, and political authorities in order to better control the conditions relating to the market economy. The valorization of local agrobiodiversity shows much potential for enhancing natural and cultural diversity in Southern countries, but only when local communities can participate in the shaping of the conditions under which this happens. Such activities should be designed in the mid- to long-term as part of social learning processes that are carefully embedded in the local context. Supporting institutions play a crucial role in these processes, but should see themselves only as facilitators, while ensuring that control and ownership remain with the local actors.
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Lymph nodes with Hodgkin disease (HD) harbor few neoplastic cells in a marked leukocytic infiltrate. Since chemokines are likely to be involved in the recruitment of these leukocytes, the expression of potentially relevant chemokines and chemokine receptors were studied in lymph nodes from 24 patients with HD and in 5 control lymph nodes. The expression of regulated on activation, normal T cell expressed and secreted (RANTES), monocyte chemotactic protein (MCP)-1, macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta was analyzed by in situ hybridization and that of CCR3 and CCR5 by immunohistochemistry and flow cytometry. It was found that, overall, the expression of all 4 chemokines was markedly enhanced, but the cellular source was different. RANTES was expressed almost exclusively by T cells whereas the expression of MCP-1, MIP-1alpha, and MIP-1beta was confined largely to macrophages. In control lymph nodes, chemokine expression was low, with the exception of MIP-1alpha in macrophages. CCR3 and CCR5 were highly expressed in T cells of HD involved but not of control lymph nodes. CCR3 was equally distributed in CD4+ and CD8+ cells, but CCR5 was associated largely with CD4+ cells. In HD lymph nodes, CCR3 and CCR5 were also expressed in B cells, which normally do not express these receptors. All these chemokines and receptors studied, by contrast, were absent in the neoplastic cells. It was concluded that chemokines are involved in the formation of the HD nonneoplastic leukocytic infiltrate. Expression of CCR3 and CCR5 appears to be characteristic of HD, but the roles of these receptors' up-regulation for the disease process remain unclear.
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The purpose of this study was to analyze the width and height of edentulous sites in the posterior maxilla using cone beam computed tomography (CBCT) images from patients referred for implant therapy. A total of 122 CBCT scans were included in the analysis, resulting in a sample size of 252 edentulous sites. The orofacial crest width was measured in coronal slices, perpendicular to the alveolar ridge. The bone height was analyzed in the respective sagittal slices. Additionally, the following secondary outcome parameters were evaluated: the morphology of the sinus floor, the presence of septa in the maxillary sinus, and the thickness of the sinus membrane. The mean crest width for all analyzed sites was 8.28 mm, and the mean bone height was 7.22 mm. The percentage of patients with a crest width of less than 6 mm was 27% in premolar sites and 7.8% in molar sites. The bone height decreased from premolar to molar areas, with a high percentage of first and second molar sites exhibiting a bone height of less than 5 mm (54.12% and 44.64%, respectively). Regarding the morphology of the sinus floor, 53% of the edentulous sites exhibited a flat configuration. A septum was present in 67 edentulous sites (26.59%). Analysis of the sinus membrane revealed 88 sites (34.9%) with increased mucosal thickness (> 2 mm). For the crest width, the location of the edentulous site and the morphology of the sinus floor were both statistically significant variables. For the crest width and mean bone height, the location of the edentulous site and the morphology of the sinus floor were both statistically significant variables. The study confirmed that a high percentage of edentulous sites in the posterior maxilla do require sinus floor elevation to allow the placement of dental implants. Therefore, a detailed three-dimensional radiograph using CBCT is indicated in most patients for proper treatment planning.
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Only a few sites in the Alps have produced archaeological finds from melting ice. To date, prehistoric finds from four sites dating from the Neolithic period, the Bronze Age, and the Iron Age have been recovered from small ice patches (Schnidejoch, Lötschenpass, Tisenjoch, and Gemsbichl/Rieserferner). Glaciers, on the other hand, have yielded historic finds and frozen human remains that are not more than a few hundred years old (three glacier mummies from the 16th to the 19th century and military finds from World Wars I and II). Between 2003 and 2010, numerous archaeological finds were recovered from a melting ice patch on the Schnidejoch in the Bernese Alps (Cantons of Berne and Valais, Switzerland). These finds date from the Neolithic period, the Early Bronze Age, the Iron Age, Roman times, and the Middle Ages, spanning a period of 6000 years. The Schnidejoch, at an altitude of 2756 m asl, is a pass in the Wildhorn region of the western Bernese Alps. It has yielded some of the earliest evidence of Neolithic human activity at high altitude in the Alps. The abundant assemblage of finds contains a number of unique artifacts, mainly from organic materials like leather, wood, bark, and fibers. The site clearly proves access to high-mountain areas as early as the 5th millennium BC, and the chronological distribution of the finds indicates that the Schnidejoch pass was used mainly during periods when glaciers were retreating.
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BACKGROUND AND STUDY AIMS Colorectal cancer (CRC) incidence ranks third among all cancers in Switzerland. Screening the general population could decrease CRC incidence and mortality. The aim of this study was to analyze the use of the fecal occult blood test (FOBT) and lower gastrointestinal endoscopy in a representative sample of the Swiss population aged ≥ 50 years. METHODS Data were analyzed from the 2007 Swiss Health Interview Survey and the prevalence estimates and 95 % confidence intervals were calculated based on all instances of lower gastrointestinal endoscopy and FOBT use, as well as on their use for CRC screening. Uni- and multivariate logistic regression analyses were performed to describe the association between screening use and sociodemographic characteristics, indicators of healthcare system use, and lifestyle factors. RESULTS In 2007, approximately 36 % of the surveyed people who were aged ≥ 50 years had previously undergone FOBT and approximately 30 % had previously undergone lower gastrointestinal endoscopy. CRC screening use was 7.7 % for FOBT (within the past year) and 6.4 % for lower gastrointestinal endoscopy (within the past 5 years). CRC screening by either method was 13 %. The major determinants of participation in CRC screening were found to be sex (male), physician visits during the past year (one or more), type of health insurance (private), and previous screening for other cancer types. CONCLUSIONS The results of the 2007 Swiss Health Interview Survey indicate rather low levels of FOBT and lower gastrointestinal endoscopy use. Furthermore, the results suggest disparities in the use of CRC screening.