RESUMO
On 9 October 2011, the University Hospital of North Norway alerted the Norwegian Institute of Public Health (NIPH) about an increase in Shigella sonnei infections in Tromsø. The isolates had an identical 'multilocus variable-number tandem repeat analysis' (MLVA) profile. Most cases had consumed food provided by delicatessen X. On 14 October, new S. sonnei cases with the same MLVA-profile were reported from Sarpsborg, south-eastern Norway. An outbreak investigation was started to identify the source and prevent further cases. All laboratory-confirmed cases from both clusters were attempted to be interviewed. In addition, a cohort study was performed among the attendees of a banquet in Tromsø where food from delicatessen X had been served and where some people had reported being ill. A trace-back investigation was initiated. In total, 46 cases were confirmed (Tromsø= 42; Sarpsborg= 4). Having eaten basil pesto sauce or fish soup at the banquet in Tromsø were independent risk factors for disease. Basil pesto was the only common food item that had been consumed by confirmed cases occurring in Tromsø and Sarpsborg. The basil had been imported and delivered to both municipalities by the same supplier. No basil from the specific batch was left on the Norwegian market when it was identified as the likely source. As a result of the multidisciplinary investigation, which helped to identify the source, the Norwegian Food Safety Authority, together with NIPH, planned to develop recommendations for food providers on how to handle fresh plant produce prior to consumption.
Assuntos
Surtos de Doenças , Disenteria Bacilar/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Ocimum basilicum/microbiologia , Shigella sonnei/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Busca de Comunicante , Disenteria Bacilar/microbiologia , Feminino , Contaminação de Alimentos , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Noruega/epidemiologia , Vigilância da População , Shigella sonnei/genética , Shigella sonnei/isolamento & purificação , Sequências de Repetição em Tandem , Adulto JovemRESUMO
BACKGROUND: The importance of consumer involvement in health care is widely recognised. Consumers can be involved in developing healthcare policy and research, clinical practice guidelines and patient information material, through consultations to elicit their views or through collaborative processes. Consultations can be single events, or repeated events, large or small scale. They can involve individuals or groups of consumers to allow debate; the groups may be convened especially for the consultation or be established consumer organisations. They can be organised in different forums and through different media. We anticipated finding few comparative evaluations that reliably evaluated the effects of consumer involvement. OBJECTIVES: To assess the effects of consumer involvement and compare different methods of involvement in developing healthcare policy and research, clinical practice guidelines, and patient information material. SEARCH STRATEGY: We searched: the Cochrane Consumers and Communication Review Group's Specialised Register (4 May 2006); the Cochrane Controlled Trials Register (CENTRAL) (The Cochrane Library, Issue 1 2006), MEDLINE (1966 to January Week 2 2006); EMBASE (1980 to Week 03 2006); CINAHL (1982 to December Week 2 2005), PsycINFO (1806 to January Week 3 2006); Sociological Abstracts (1952 to 24 January 2006); and SIGLE (System for Information on Grey Literature in Europe) (1980 to 2003/1). We scanned reference lists from relevant articles and contacted authors. SELECTION CRITERIA: Randomised and quasi-randomised trials, interrupted time series analyses, and controlled before-after studies assessing methods for involving consumers in developing healthcare policy and research, clinical practice guidelines or patient information material. The outcome measures were: participation or response rates of consumers; consumer views elicited; consumer influence on decisions, healthcare outcomes or resource utilisation; consumers' or professionals' satisfaction with the involvement process or resulting products; impact on the participating consumers; costs. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion, assessed their quality and extracted data. We contacted study authors for clarification and to seek missing data. We presented results in a narrative summary and pooled data as appropriate. MAIN RESULTS: Five randomised controlled trials of moderate or low methodological quality involving 1031 participants were included. There is moderate quality evidence that involving consumers in the development of patient information material results in material that is more relevant, readable and understandable to patients, without affecting their anxiety. This 'consumer-informed' material can also improve patients' knowledge. There is low quality evidence that using consumer interviewers instead of staff interviewers in satisfaction surveys can have a small influence on the survey results. There is very low quality evidence of telephone discussions and face-to-face group meetings engaging consumers better than mailed surveys in order to set priorities for community health goals, and resulting in different priorities being set for these goals. AUTHORS' CONCLUSIONS: There is little evidence from comparative studies of the effects of consumer involvement in healthcare decisions at the population level. The studies included in this review demonstrate that randomised controlled trials are feasible for providing evidence about the effects of consulting consumers to inform these decisions.
Assuntos
Participação da Comunidade/métodos , Política de Saúde , Pesquisa sobre Serviços de Saúde , Educação de Pacientes como Assunto , Guias de Prática Clínica como Assunto , Humanos , Defesa do PacienteRESUMO
Photosynthesis (Pn) was measured in stems of two desert legumes, Caesalpinia virgata at a low elevation site (118 m) in the Sonoran Desert and Senna armata at a higher elevation (950 m) in the Mojave Desert. The lower elevation site experienced higher spring and summer temperatures than the higher elevation site, but the air vapor pressure, irradiance, and rainfall patterns were similar. Mid-morning maximum stem Pn was highest in May for C. virgata (7.8 [mu]mol m-2 s-1) and in July for S. armata (5.8 [mu]mol m-2 s-1). The seasonal variation in maximum stem Pn was not associated with changes in bulk tissue water potential or chlorenchyma tissue nitrogen concentration. The main environmental regulators of seasonal stem Pn were temperature and leaf to air vapor pressure gradient. Light-response curves indicated no major differences in apparent quantum yield or light compensation point between the spring and summer, but light-saturated stem Pn at ambient temperature decreased for C. virgata between these seasons. The optimal temperature for stem Pn remained the same for both species between the spring and the summer. However, stem Pn of both species increased at all temperatures between the spring and summer. Potential stem Pn under optimal conditions and CO2-saturated stem Pn increased for both species between spring and summer. The increase in stem Pn potential allowed these species to maintain stem Pn during the summer even though stem Pn responses to temperature and vapor pressure did not acclimate to seasonal climatic conditions.
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Nanoparticles are emerging contaminants of concern. Knowledge on their environmental impacts is scarce, especially on their interactive effects with other contaminants. In this study we investigated effects of titanium dioxide nanoparticles (TiO2NP) on the blue mussel (Mytilus edulis) and determined their influence on the bioavailability and toxicity of benzo(a)pyrene (B(a)P), a carcinogenic polyaromatic hydrocarbon (PAH). Blue mussels were exposed to either TiO2NP (0.2 and 2.0 mg L(-1)) or B(a)P (20 µg L(-1)) and to the respective combinations of these two compounds. Aqueous contaminant concentrations, the uptake of Ti and B(a)P into mussel soft tissue, effects on oxidative stress and chromosomal damage were analyzed. The uncoated TiO2NP agglomerated rapidly in the seawater. The presence of TiO2NP significantly reduced the bioavailability of B(a)P, shown by lowered B(a)P concentrations in exposure tanks and in mussel tissue. The activities of antioxidant enzyme superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were impacted by the various exposure regimes, indicating oxidative stress in the contaminant exposure groups. While SOD activity was increased only in the 0.2TiO2NP exposure group, CAT activity was enhanced in both combined exposure groups. The GPx activity was increased only in the groups exposed to the two single compounds. In hemocytes, increased chromosomal damage was detected in mussels exposed to the single compounds, which was further increased after exposure to the combination of compounds. In this study we show that the presence of TiO2NP in the exposure system reduced B(a)P uptake in blue mussels. However, since most biomarker responses did not decrease despite of the lower B(a)P uptake in combined exposures, the results suggest that TiO2NP can act as additional stressor, or potentially alters B(a)P toxicity by activation.
Assuntos
Benzo(a)pireno/toxicidade , Mytilus edulis/fisiologia , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Benzo(a)pireno/metabolismo , Biomarcadores/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Nanopartículas/química , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Titânio/química , Poluentes Químicos da Água/metabolismoRESUMO
Low density lipoproteins (LDL) isolated by ultracentrifugation induce cytotoxic changes in cultured human endothelial cells (EC) and fibroblasts if the ratio between LDL cholesterol and the final protein concentration of the culture medium exceeds 0.10-0.12 mmol/g protein. In order to investigate if reactive oxygen species could contribute to the cytotoxicity, LDL were prepared in the presence of the antioxidants butylated hydroxytoluene (BHT) or superoxide dismutase (SOD), while routinely prepared LDL from the same donors served as control (N-LDL). A radiochromium release assay was used to evaluate cellular injury. BHT treatment of the LDL fraction virtually abolished LDL-induced cytotoxicity in cultured human EC and fibroblasts. SOD-LDL offered partial protection against LDL cytotoxicity. A positive correlation between the cytotoxicity of the various fractions and their content of malondialdehyde (MDA) further supports our conclusion that lipid peroxides in the LDL fractions mediate the cytotoxic effect on cultured cells.
Assuntos
Lipoproteínas LDL/toxicidade , Hidroxitolueno Butilado/farmacologia , Células Cultivadas , Endotélio/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Lipoproteínas LDL/antagonistas & inibidores , Lipoproteínas LDL/metabolismo , Malondialdeído/metabolismo , Superóxido Dismutase/farmacologiaRESUMO
Cultured human umbilical vein endothelial cells responded to thrombin (10(-2) - 10 NIH u/ml) with a 2-5 fold increase in thromboplastin activity. The maximum response was reached after 4 hr in serum-free medium. The effect of thrombin was fully inhibited by the presence of 50% (v/v) fetal calf serum or more in the medium, by preincubation of thrombin with hirudin or by treatment of thrombin with N-bromosuccinimide or phenylmethylsulfonyl fluoride. The thrombin-induced thromboplastin activity was inhibited by incubation of the cells with cycloheximide (2 micrograms/ml) or actinomycin D (2 micrograms/ml) showing that the response depended on de novo protein and RNA synthesis. It was also suppressed by exposure of the cells to two different phosphodiesterase inhibitors, 3-butyl-1-methyl-xanthine (5 X 10(-4) M) and rac-4 (3-butoxy-4-methoxybenzyl)-2-imidazole (5 X 10(-4) M), to the transmethylation inhibitors 3-deazaadenosine (10(-5) M) and 1-homocysteine thiolactone (2 X 10(-5) M) in combination and to the intracellular calcium antagonist 8-(N,N-diethylamino)-octyl 3,4,5,-tri-methoxybenzoate hydrochloride (8 X 10(-5) M). Our results suggest that small amounts of thrombin can induce thromboplastin synthesis in endothelial cells in vitro and that this synthesis probably is regulated by the intracellular level of cAMP, by cytoplasmic Ca2+ and possibly also by transmethylation reactions.
Assuntos
Endotélio/metabolismo , Trombina/farmacologia , Tromboplastina/biossíntese , 1-Metil-3-Isobutilxantina/farmacologia , Células Cultivadas , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Endotélio/citologia , Endotélio/efeitos dos fármacos , Sangue Fetal/fisiologia , Hirudinas/farmacologia , Humanos , Trombina/antagonistas & inibidores , Veias Umbilicais/citologiaRESUMO
Confluent monolayers of human umbilical vein endothelial cells in culture responded with a 5-fold increase in thromboplastin (tissue factor) synthesis when exposed to 12-O-tetradecanoyl-phorbol-13-acetate (TPA) (50 ng/ml) or endotoxin (ETX) (25 micrograms/ml) for 16 hr. This induced thromboplastin synthesis was markedly inhibited by exposure of the cells to two different phosphodiesterase inhibitors, methylisobutylxanthine (MIX) and rac-4(3-butoxy-4-methoxybenzyl)-2-imidazole idinone (RO-20-1724) and to the transmethylation inhibitors 3-deazaadenosine (DZA) and 1-homocysteine thiolactone (Hcy) in combination. It was slightly (TPA) or not at all (ETX) inhibited upon exposure of the cells to the intracellular calcium antagonist 8-(N,N-diethylamino)-octyl 3,4, 5-trimethoxybenzoate hydrochloride (TMB-8). However, in the presence of MIX TMB-8 had a moderate additional inhibitory effect on TPA-induced thromboplastin response. The thromboplastin response of endothelial cells in vitro thus probably depends on transmethylation events for its full expression. It is also strongly modulated by the intracellular level of cAMP.
Assuntos
Endotélio/metabolismo , Tromboplastina/biossíntese , 1-Metil-3-Isobutilxantina/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio/efeitos dos fármacos , Endotoxinas/farmacologia , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacologia , Homocisteína/análogos & derivados , Homocisteína/farmacologia , Humanos , Técnicas In Vitro , Acetato de Tetradecanoilforbol/farmacologia , Tubercidina/farmacologiaRESUMO
Cultured human umbilical vein endothelial cells (EC) incubated in the presence of 2-deoxy-D-glucose (20 mmol/l) or at 4 degrees C lost their ability to undergo shape changes when exposed to thrombin (1 N.I.H. u/ml). Drugs blocking Ca++-flux (verapamil and nifedipin), microfilament disrupting agents (cytochalasin B and D) and microtubule disrupting agents (colchicine and colcemid) did not prevent thrombin-induced shape changes. None of the agents tested inhibited the accelerated thrombin-induced 51Cr-release from the cells. Pretreatment of EC with thrombin did not influence their ability to mediate clot retraction.
Assuntos
Endotélio/efeitos dos fármacos , Trombina/farmacologia , Cálcio/metabolismo , Células Cultivadas , Retração do Coágulo , Colchicina/farmacologia , Citocalasinas/farmacologia , Citoesqueleto/efeitos dos fármacos , Endotélio/citologia , Endotélio/metabolismo , Endotélio/ultraestrutura , Humanos , Microtúbulos/efeitos dos fármacos , Nifedipino/farmacologia , Temperatura , Veias Umbilicais , Verapamil/farmacologiaRESUMO
Cultures of human endothelial cells (EC) incubated for periods up to 24 h with highly purified thrombin (2 NIH u/ml) contained considerably less cell-associated fibronectin fibrils than corresponding controls. The loss of fibronectin fibrils was evident after 4 h and was accompanied by a 2-3 fold increase in the concentration of fibronectin in the incubation medium. Hirudin inhibited the effects of thrombin. Thrombin also induced characteristic shape changes of EC. These shape changes were reversible within a 4-6 h period and could not be reinvoked by new additions of thrombin. Thus, structural refractoriness to thrombin coincided temporally with a period when EC-associated fibronectin fibrils were markedly reduced.
Assuntos
Endotélio/metabolismo , Fibronectinas/metabolismo , Trombina/farmacologia , Animais , Bovinos , Células Cultivadas , Cicloeximida/farmacologia , Endotélio/efeitos dos fármacos , Humanos , Recém-Nascido , Microscopia de Fluorescência , Fatores de TempoRESUMO
Three species of shrubs (Ericaceae) were found to segregate upon the northeast and southwest slopes of spur ridges on Brush Mountain, in southwestern Virginia. Rhododendron maximum was found only in valleys and lower northeast slopes, Rhododendron periclymenoides = R. nudiflorum) was found on northeast slopes while Kalmia latifolia was most abundant on southwest slopes. Previous vegetation studies indicated that these partially segregated distributions were related to irradiance and water availability. In field studies of water potential, R. periclymenoides had the lowest diurnal leaf water potentials and the largest seasonal variation in midday leaf water potential. Kalmia latifolia had the highest leaf conductance in field and phytotron experiments. Rhododendron maximum had the greatest seasonal osmotic adjustment followed by R. periclymenoides and K. latifolia. In phytotron experiments, the photosynthetic capacity of R. maximum was the most sensitive to water stress followed by R. periclymenoides and K. latifolia. Kalmia latifolia was able to modify its conductance rates to reduce water loss and maintain constant leaf water potential minimizing photosynthetic inhibition. Rhododendron periclymenoides showed extreme luxury spending of water indicated by high conductance and low photosynthesis. The ecophysiological responses to water and irradiance provided an explanation for the distributions of the three species. For example, R. maximum leaves are sensitive to elevated irradiance, and carbon gain is strongly influenced by water stress. Thus, R. maximum will perform best in low irradiance environments with ample water, such as valley sites. Each species had a unique set of adaptations for performing best in their optimum habitat.
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Water relations of several stem succulent trees were measured in north-central Baja California in comparisons to other growth forms in the same habitat. Our research concentrated on three stem succulent species (Idria collumnaris, Pachycormus discolor and Bursera microphylla) each with a different succulent stem morphology. The stem succulent trees had 1 to 4 kg H2O/m3 of trunk while the other trees and shrubs in the same habitat had 0.6 to 0.8 kg H2O/m3. The diurnal and seasonal variation in leaf water potential was small for the stem succulent species in comparison to deciduous and evergreen species as a consequence of the stem-water, buffering capacity. In addition, the leaf conductance of the stem succulent species was low (60 mmol m-2 s-1) and yet, the leaf conductance decreased through the day similar to adjacent evergreen and deciduous species. The leaves of the stem succulent trees lost turgor at low saturated water deficits (0.06 to 0.14), had comparatively high osmotic potentials, and high values of elastic modulus in comparison to adjacent evergreen and deciduous species. The stem acts as an important buffering mechanism allowing for the maintenance of leaf turgor in these stem succulent trees. The low transpiration rates of the stem succulent trees may be a mechanism to minimize leaf saturated water deficit and extend leaf longevity.
RESUMO
Water and nitrogen regimes of Larrea tridentata shrubs growing in the field were manipulated during an annual cycle. Patterns of leaf water status, leaf water relations characteristics, and stomatal behavior were followed concurrently. Large variations in leaf water status in both irrigated and nonirrigated individuals were observed. Predawn and midday leaf water potentials of nonirrigated shrubs were lowest except when measurements had been preceded by significant rainfall. Despite the large seasonal variation in leaf water status, reasonably constant, high levels of turgor were maintained. Pressure-volume curve analysis suggested that changes in the bulk leaf osmotic potential at full turgor were small and that nearly all of the turgor adjustment was due to tissue elastic adjustment. The increase in tissue elasticity with increasing water deficit manifested itself as a decrease in the relative water content at zero turgor and as a decrease in the tissue bulk elastic modulus. Because of large hydration-induced displacement in the osmotic potential and relative water content at zero turgor, it was necessary to use shoots in their natural state of hydration for pressure-volume curve determinations. Large diurnal and seasonal differences in maximum stomatal conductance were observed, but could not easily be attributed to variations in leaf water potential or leaf water relations characteristics such as the turgor loss point. The single factor which seemed to account for most of the diurnal and seasonal differences in maximum stomatal conductance between individual shrubs was an index of soil/root/ shoot hydraulic resistance. Daily maximum stomatal conductance was found to decrease with increasing soil/root/ shoot hydraulic resistance. This pattern was most consistent if the hydraulic resistance calculation was based on an estimate of total canopy transpiration rather than the more commonly used transpiration per unit leaf area. The reasons for this are discussed. It is suggested that while stomatal aperture necessarily represents a major physical resistance controlling transpiration, plant hydraulic resistance may represent the functional resistance through its effects on stomatal aperture.
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Seasonal measurements of microclimatic conditions were compared to seasonal indices of leaf structural components and plant water relations in Prosopis glandulosa var. torryana. P. glandulosa had two short periods of leaf production which resulted in two distinct even aged cohorts of leaves. The two leaf cohorts (summer, winter) were concurrent in the summer and fall, contrasting to previous studies on other species in which one leaf form replaces a previous leaf type. The structural characteristics of these two cohorts differed significantly in two replicate year cycles. The leaves of the spring cohort were larger in weight and area but similar to the summer cohort in specific leaf weight and leaflet number. The second growth period leaves constituted only a small proportion of the total plant leaf area. The dimorphism between the two cohorts was best associated with plant water relations and not energy load. Second growth period leaves maintained turgor to greater water deficits but lost turgor at higher leaf water potentials. Seasonal osmotic adjustment occurred for first growth period leaves but not second growth period leaves. The small leaves produced during the hot climate were most likely the result of low turgor potential during development rather than an adaptation to tolerate stressful environments.
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The 15N abundance of tissues of five Prosopis specimens at our primary study site (a Prosopis woodland at Harper's Well in the Sonoran desert of Southern California) was determined over two growing seasons 1980 and 1981. The 15N abundance of soil and of tissues of presumed non-N2-fixing (control) plants was also measured. Prosopis tissues were significantly lower in 15N than either soil N or corresponding tissues of presumed non-N2-fixing plants which derive their N entirely from soil. Soil N was also significantly higher in 15N than atmospheric N2. We conclude that it is feasible to use variations in the natural abundance of 15N as an index of N2-fixation in this kind of ecosystem, and that N2-fixation is of considerable importance to Prosopis growing at this site.We also determined the 15N abundance of leaf tissue of presumed N2-fixing and control plants growing at the same site at six additional sites (five in the Sonoran desert of southern California and one in Baja California, Mexico near the town of Catavina). Four of these additional sites were dominated by Prosopis and two were mixed communities. There were statistically significant differences between the 15N abundances of the pooled legume population and control plants at all sites, although not every legume specimen exhibited this difference. From 15N abundance data we estimated the fractional contribution of biologically fixed N to the N economy of desert legumes. We concluded that N2-fixation is very important to Prosopis at six of seven sites in the Sonoran Desert. At the site where Prosopis did not appear to be fixing N2, N2-fixation was important only for legumes of the sub-family Papilionoideae, Lupinus, Dalea, Astragalus and Lotus.
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Cytokines are known to play a key regulatory role in immune responses. The onset or progression of immunopathology in various diseases is often associated with aberrant production of one or more cytokines. It is therefore of considerable interest to characterize cytokine "profiles" associated with disease processes. Many methods employed for identification and quantification of cytokines produced by different cell types rely on the responsiveness of indicator cell lines. Such bioassays are technically restrictive owing to the time required for performance and because of sensitivity and specificity problems. Enzyme-linked immunosorbent assays (ELISAs), on the other hand, detect both biologically active and inactive cytokines without discrimination. These assays are easy to use, but the commercial kits are usually expensive. Both bioassays and ELISAs are unable to identify actual cytokine production and do not account for cytokines consumed by cells. In addition, the minute amounts of cytokine protein often produced in autocrine or paracrine microenvironments may not be easily detectable in a sample, especially when tissue or cells are available in only small quantities (1). Furthermore, although cells producing cytokine protein may be detected by immunocyto/histochemistry, only a limited number of antibodies with good performance are available (2), and the possibility of confusing synthesis with cellular uptake of cytokines exists.
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Ireland is experiencing one of the highest periods of emigration in its history. The current study collected demographic and psychological data on 203 Irish men and women in Ireland and in Northern Ireland, including measures of self-esteem, depression, attitudes toward immigration, and expectancies of emigration. Analysis indicated that approximately 81% of this Irish sample are considering emigration; however, the prospect of emigration is psychologically experienced differently by men and women. While there were no significant differences over-all in scores on self-esteem between Irish men and women, men who contemplated emigration reported higher self-esteem scores, and women contemplating emigration reported lower self-esteem scores (relative to those who had no plan to emigrate). In addition, women who contemplated emigration had higher depression scores than women who did not contemplate emigration. This pattern was not evident for men. These results indicate that psychologically women view the prospect of emigration less positively than men.
Assuntos
Atitude , Depressão/psicologia , Emigração e Imigração , Identidade de Gênero , Problemas Sociais/psicologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Motivação , Irlanda do Norte , AutoimagemRESUMO
The ability of high-density lipoprotein (HDL) to reduce the cholesterol content was studied in cultured fibroblasts enriched with cholesterol esters. Incubation of cholesterol-enriched cells with HDL in a final concentration of 1 g protein/l for 24 h reduced the total and esterified cholesterol content by 23% as compared with control fibroblasts incubated with albumin. Similar cholesterol efflux was obtained with HDL isolated from lecithin:cholesterol acyltransferase (LCAT)-deficient plasma. The HDL3 subfraction isolated by rate-zonal ultracentrifugation contained the major part of the cholesterol-depleting effect. HDL or HDL3 decreased CoA:cholesterol acyltransferase (ACAT) activity to 5% of the level found in control fibroblasts within 8 h of incubation. These findings suggest that ACAT activity is sensitive to a pool of intracellular cholesterol, which can be mobilized by the addition of HDL to the culture medium, and that ACAT activity is a useful measure of cholesterol efflux from cultured fibroblasts.
Assuntos
Colesterol/metabolismo , Fibroblastos/metabolismo , Lipoproteínas HDL/farmacologia , Pele/citologia , Células Cultivadas , Fibroblastos/enzimologia , Humanos , Lipoproteínas/sangue , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismoRESUMO
Persistent organochlorine pollutants such as polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p'-DDE), and polybrominated diphenyl ethers (PBDEs) are stable, bioaccumulative, and widely found in the environment, wildlife, and the human population. To explore the hypothesis that reproduction in male fish is associated with environmental exposures in the lower Columbia River (LCR), reproductive and endocrine parameters were studied in male resident, non-anadromous largescale sucker (Catostomus macrocheilus) (LSS) in the same habitats as anadromous salmonids having conservation status. Testes, thyroid tissue and plasma collected in 2010 from Longview (LV), Columbia City (CC), and Skamania (SK; reference) were studied. Sperm morphologies and thyrocyte heights were measured by light microscopy, sperm motilities by computer-assisted sperm motion analysis, sperm adenosine triphosphate (ATP) with luciferase, and plasma vitellogenin (VTG), thyroxine (T4), and triiodothyronine (T3) by immunoassay. Sperm apoptosis, viability, mitochondrial membrane potential, nuclear DNA fragmentation, and reproductive stage were measured by flow cytometry. Sperm quality parameters (except counts) and VTG were significantly different among sites, with correlations between VTG and 7 sperm parameters. Thyrocyte heights, T4, T3, gonadosomatic index and Fulton's condition factor differed among sites, but not significantly. Sperm quality was significantly lower and VTG higher where liver contaminants and water estrogen equivalents were highest (LV site). Total PCBs (specifically PCB-138, -146, -151, -170, -174, -177, -180, -183, -187, -194, and -206) and total PBDEs (specifically BDE-47, -100, -153, and -154) were negatively correlated with sperm motility. PCB-206 and BDE-154 were positively correlated with DNA fragmentation, and pentachloroanisole and VTG were positively correlated with sperm apoptosis and negatively correlated with ATP. BDE-99 was positively correlated with sperm counts and motility; T4 was negatively correlated with counts and positively correlated with motility, thus indicating possible androgenic mechanisms and thyroid endocrine disruption. Male LSS proved to be an informative model for studying reproductive and endocrine biomarkers in the LCR.
Assuntos
Cipriniformes/fisiologia , Monitoramento Ambiental , Poluentes Químicos da Água/toxicidade , Animais , Diclorodifenil Dicloroetileno/metabolismo , Diclorodifenil Dicloroetileno/toxicidade , Disruptores Endócrinos/análise , Disruptores Endócrinos/toxicidade , Éteres Difenil Halogenados/metabolismo , Éteres Difenil Halogenados/toxicidade , Humanos , Masculino , Bifenil Polibromatos/metabolismo , Bifenil Polibromatos/toxicidade , Bifenilos Policlorados/metabolismo , Bifenilos Policlorados/toxicidade , Reprodução/fisiologia , Rios , Tiroxina/metabolismo , Vitelogeninas/metabolismo , Poluentes Químicos da Água/análiseRESUMO
We investigated the prevalence of extended-spectrum ß-lactamases (ESBLs) in Enterobacter spp. bloodstream isolates from 19 hospital laboratories in Norway during 2011. A total of 62/230 (27%) isolates were resistant to third-generation cephalosporins and four (1.7%) were ESBL-positive; blaCTX -M-15 (n = 3) and blaSHV -12 (n = 1). This is comparable to the prevalence of ESBLs in clinical isolates of Escherichia coli and Klebsiella pneumoniae in Norway during the same period. All ESBL-positive isolates were multidrug resistant (MDR) and harboured plasmid-mediated quinolone resistance. Three isolates supported transfer of large IncHI2-plasmids harbouring ESBL- and MDR-encoding genes to E. coli recipients by in vitro conjugation.