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We compared the sensitivity of closely related Pacific salmon and steelhead (Oncorhynchus spp.) to untreated urban stormwater runoff across three storm events. Juvenile coho, sockeye, steelhead, and Chinook were exposed for 24 h to untreated urban runoff and then transferred to clean water for 48 h. As anticipated from previous studies, coho were highly susceptible to runoff toxicity, with cumulative mortality rates ranging from 92%-100% across the three storms. By contrast, juvenile sockeye were unaffected (100% survival), and cumulative mortality rates were intermediate for steelhead (4%-42%) and Chinook (0%-13%). Furthermore, coho died rapidly following the onset of stormwater exposure (generally <4 h), whereas mortality in Chinook and steelhead was delayed by 1-2 days. Similar to previous findings for coho, steelhead and Chinook did not recover when transferred to clean water. Lastly, significant mortality occurred in coho even when roadway runoff was diluted by 95% in clean water. Our findings extend the urban runoff mortality syndrome in salmonids and point to a near-term need for sublethal studies in steelhead and Chinook to more precisely understand stormwater risks to threatened species recovery efforts in the western United States.
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Urbanization-driven landscape changes are harmful to many species. Negative effects can be mitigated through habitat preservation and restoration, but it is often difficult to prioritize these conservation actions. This is due, in part, to the scarcity of species response data, which limit the predictive accuracy of modeling to estimate critical thresholds for biological decline and recovery. To address these challenges, we quantify effort required for restoration, in combination with a clear conservation objective and associated metric (e.g., habitat for focal organisms). We develop and apply this framework to coho salmon (Oncorhynchus kisutch), a highly migratory and culturally iconic species in western North America that is particularly sensitive to urbanization. We examine how uncertainty in biological parameters may alter locations prioritized for conservation action and compare this to the effect of shifting to a different conservation metric (e.g., a different focal salmon species). Our approach prioritized suburban areas (those with intermediate urbanization effects) for preservation and restoration action to benefit coho. We found that prioritization was most sensitive to the selected metric, rather than the level of uncertainty or critical threshold values. Our analyses highlight the importance of identifying metrics that are well-aligned with intended outcomes.
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The stomatogastric ganglion (STG) of the crab Cancer productus contains approximately 30 neurons arrayed into two different networks (gastric mill and pyloric), each of which produces a distinct motor pattern in vitro. Here we show that the functional division of the STG into these two networks requires intact NO-cGMP signaling. Multiple nitric oxide synthase (NOS)-like proteins are expressed in the stomatogastric nervous system, and NO appears to be released as an orthograde transmitter from descending inputs to the STG. The receptor of NO, a soluble guanylate cyclase (sGC), is expressed in a subset of neurons in both motor networks. When NO diffusion or sGC activation are blocked within the ganglion, the two networks combine into a single conjoint circuit. The gastric mill motor rhythm breaks down, and several gastric neurons pattern switch and begin firing in pyloric time. The functional reorganization of the STG is both rapid and reversible, and the gastric mill motor rhythm is restored when the ganglion is returned to normal saline. Finally, pharmacological manipulations of the NO-cGMP pathway are ineffective when descending modulatory inputs to the STG are blocked. This suggests that the NO-cGMP pathway may interact with other biochemical cascades to partition rhythmic motor output from the ganglion.
Assuntos
GMP Cíclico/metabolismo , Gânglios dos Invertebrados/metabolismo , Rede Nervosa/metabolismo , Óxido Nítrico/metabolismo , Animais , Arginina/farmacologia , Braquiúros , Citrulina/metabolismo , Sistema Digestório/inervação , Inibidores Enzimáticos/farmacologia , Corantes Fluorescentes , Gânglios dos Invertebrados/citologia , Gânglios dos Invertebrados/efeitos dos fármacos , Guanilato Ciclase/antagonistas & inibidores , Guanilato Ciclase/metabolismo , Imuno-Histoquímica , Técnicas In Vitro , Isoquinolinas , Masculino , Rede Nervosa/efeitos dos fármacos , Neurônios/classificação , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurotransmissores/metabolismo , Doadores de Óxido Nítrico/farmacologia , Periodicidade , Transdução de Sinais/efeitos dos fármacosRESUMO
In recent years, an increasing number of studies reporting on meniscal root tears have been published. While the meniscus and its ligamentous meniscal attachments have been studied before, little is known about the transitional zone between these two structures. Therefore, the aim of this study was to mechanically and morphologically characterize the transitional zone between meniscus and its meniscal attachments. Dumbbell-shaped specimens were obtained from the transitional zone between meniscus and its meniscal attachments of 6 knee joints. Samples were divided into tibial and central layers of the anterior lateral (AL), anterior medial (AM), posterior lateral (PL) and posterior medial (PM) transitional region. Testing was performed to obtain the dissipated energy during hysteresis as well as the linear modulus (Elin), the maximum strain (εmax), the maximum engineering stress (σmax,eng) and location of rupture during tensile test to failure. Two additional knee joints were used to investigate morphological differences between meniscus, transitional zone and meniscal attachments in 8µm transverse slices. The central layer of the AL, AM and PL dissipated up to 48% less energy than the tibial layer. Elin was highest in the tibial layer of the PM with 107.4±61.1MPa and lowest in the central layer of the PL with 56.0±20.5MPa. The maximum strain was higher in the central layer than in the tibial layer at the AL, AM, and PL locations. The average σmax,eng was 12.7±9.9MPa over all location and layers. 78% of the samples ruptured during tensile test to failure in the transitional zone. The morphological evaluation showed a smooth transitional zone with a transitional curve which was either linear or bell-shaped. The strength found in the transitional zone was lower than in the meniscus and the meniscal attachments, which corresponds well to clinical findings.
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Meniscos Tibiais/fisiologia , Idoso , Fenômenos Biomecânicos , Módulo de Elasticidade , Feminino , Humanos , Masculino , Meniscos Tibiais/anatomia & histologia , Pessoa de Meia-IdadeRESUMO
Green stormwater infrastructure (GSI), or low impact development, encompasses a diverse and expanding portfolio of strategies to reduce the impacts of stormwater runoff on natural systems. Benchmarks for GSI success are usually framed in terms of hydrology and water chemistry, with reduced flow and loadings of toxic chemical contaminants as primary metrics. Despite the central goal of protecting aquatic species abundance and diversity, the effectiveness of GSI treatments in maintaining diverse assemblages of sensitive aquatic taxa has not been widely evaluated. In the present study we characterized the baseline toxicity of untreated urban runoff from a highway in Seattle, WA, across six storm events. For all storms, first flush runoff was toxic to the daphniid Ceriodaphnia dubia, causing up to 100% mortality or impairing reproduction among survivors. We then evaluated whether soil media used in bioretention, a conventional GSI method, could reduce or eliminate toxicity to juvenile coho salmon (Oncorhynchus kisutch) as well as their macroinvertebrate prey, including cultured C. dubia and wild-collected mayfly nymphs (Baetis spp.). Untreated highway runoff was generally lethal to salmon and invertebrates, and this acute mortality was eliminated when the runoff was filtered through soil media in bioretention columns. Soil treatment also protected against sublethal reproductive toxicity in C. dubia. Thus, a relatively inexpensive GSI technology can be highly effective at reversing the acutely lethal and sublethal effects of urban runoff on multiple aquatic species.
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Invertebrados , Oncorhynchus kisutch , Chuva , Solo , Poluentes da Água/toxicidade , Animais , Cidades , Cadeia AlimentarRESUMO
A fumigation experiment was performed in which six plant species representing the European flora were exposed to a range of DBP concentrations. Controlled amounts of DBP-saturated air were injected into the ingoing air-streams of plant fumigation chambers, maintaining constant concentrations there for a period of up to 76 days. The target concentrations were a control, 0.8, 1.5, 3.5, and 10.0 microg m(-3). The variation in sensitivity between plant species to atmospheric DBP was quantified on the basis of whole plant biomass in order to derive no-observed-effect-concentrations (NOECs). Significant dose-response relationships, based on realised concentrations, were thus derived using non-linear regression, resulting in NOECs of 0.51 microg m(-3) for Trifolium repens, 0.96 microg m(-3) for Brassica campestris, 1.87 microg m(-3) for Phaseolus vulgaris and 2.21 microg m(-3) for Plantago major. A significant effect was also observed for Holcus lanatus at 12.4 microg m(-3) DBP, but due to the variation at lower levels of DBP exposure, no dose-response relationship could be derived. No significant effect on growth of current year needles in Picea abies was observed, even at the highest level of DBP, 13.7 microg m(-3). Based on statistical extrapolation according to Aldenberg and Slob [Ecotox. Environ. Safety, 25 (1993) 48], an overall predicted no-effect concentration (PNEC) for the plant-atmosphere compartment of 0.33 microg m(-3) DBP was calculated. The PNEC was calculated using the mean and standard deviation of the NOEC for four of the tested species and an extrapolation factor. In addition to changes in leaf colour, leaf crinkling and growth reduction, a number of not quantified observations are described, indicating that DBP affects the physiology as well as the morphology of these species.
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Dibutilftalato/toxicidade , Fumigação , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/metabolismo , Poluição do Ar/análise , Biomassa , Europa (Continente) , Magnoliopsida/fisiologia , Nível de Efeito Adverso não Observado , Folhas de Planta/anatomia & histologia , Medição de RiscoRESUMO
Differences in the costs of health care systems among industrialized countries has been the focus of several studies. Labor costs, specifically the amount of resources used for administration, are considered to contribute to differences in overall health care costs. To determine differences in the use of labor resources, especially administrative and managerial, among American, Austrian and German hospitals, we use a convenience sample of one Austrian, one German and two United States (US) tertiary care centers. In our analysis we used payroll data of the four hospitals. First, we categorized job titles and created job categories. Subsequently, we calculated full time equivalents (FTEs) per job category and compared them across countries. Adjustments were made for differences in health systems. The main outcome measures were FTEs per patient day and per discharge in each job category. In the US hospitals > 19% of FTEs were in administrative categories as compared with < 8% in the European hospitals. For administrative managers, US hospitals used > 11 times the labor per patient day of the European institutions. Among administrative areas, the largest absolute FTE difference was in financial operations. US hospitals used > 5 FTEs of personnel per 10,000 patient days versus < 1.0 FTE in the European hospitals. Given the kinds of administrative work done in US hospitals compared to Austria and Germany, differences in the organization and financing of these countries' health care systems may account for an important part of the higher number of US personnel.
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Comparação Transcultural , Administração Hospitalar/economia , Programas Nacionais de Saúde/economia , Áustria , Controle de Custos , Alemanha , Humanos , Recursos Humanos em Hospital/economia , Recursos Humanos em Hospital/estatística & dados numéricos , Estados Unidos , Recursos HumanosRESUMO
Urban stormwater contains a complex mixture of contaminants that can be acutely toxic to aquatic biota. Green stormwater infrastructure (GSI) is a set of evolving technologies intended to reduce impacts on natural systems by slowing and filtering runoff. The extent to which GSI methods work as intended is usually assessed in terms of water quantity (hydrology) and quality (chemistry). Biological indicators of GSI effectiveness have received less attention, despite an overarching goal of protecting the health of aquatic species. Here we use the zebrafish (Danio rerio) experimental model to evaluate bioinfiltration as a relatively inexpensive technology for treating runoff from an urban highway with dense motor vehicle traffic. Zebrafish embryos exposed to untreated runoff (48-96h; six storm events) displayed an array of developmental abnormalities, including delayed hatching, reduced growth, pericardial edema, microphthalmia (small eyes), and reduced swim bladder inflation. Three of the six storms were acutely lethal, and sublethal toxicity was evident across all storms, even when stormwater was diluted by as much as 95% in clean water. As anticipated from exposure to cardiotoxic polycyclic aromatic hydrocarbons (PAHs), untreated runoff also caused heart failure, as indicated by circulatory stasis, pericardial edema, and looping defects. Bioretention treatment dramatically improved stormwater quality and reversed nearly all forms of developmental toxicity. The zebrafish model therefore provides a versatile experimental platform for rapidly assessing GSI effectiveness.
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Monitoramento Ambiental/métodos , Poluentes do Solo/análise , Solo/química , Poluentes Químicos da Água/análise , Animais , Hidrocarbonetos Policíclicos Aromáticos/análise , Movimentos da Água , Peixe-ZebraRESUMO
Urban streams of the Pacific Northwest provide spawning and rearing habitat for a variety of salmon species, and food availability for developing salmon could be adversely affected by pesticide residues in these waterbodies. Sediments from Oregon and Washington streams were sampled to determine if current-use pyrethroid insecticides from residential neighborhoods were reaching aquatic habitats, and if they were at concentrations acutely toxic to sensitive invertebrates. Approximately one-third of the 35 sediment samples contained measurable pyrethroids. Bifenthrin was the pyrethroid of greatest concern with regards to aquatic life toxicity, consistent with prior studies elsewhere. Toxicity to Hyalella azteca and/or Chironomus dilutus was found in two sediment samples at standard testing temperature (23 °C), and in one additional sample at a more environmentally realistic temperature (13 °C). Given the temperature dependency of pyrethroid toxicity, low temperatures typical of northwest streams can increase the potential for toxicity above that indicated by standard testing protocols.
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Inseticidas/análise , Piretrinas/análise , Rios/química , Poluentes Químicos da Água/análise , Anfípodes/efeitos dos fármacos , Animais , Chironomidae/efeitos dos fármacos , Cidades , Ecossistema , Monitoramento Ambiental , Inseticidas/toxicidade , Noroeste dos Estados Unidos , Piretrinas/toxicidade , Salmão/fisiologia , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/estatística & dados numéricosAssuntos
Cannabis/farmacologia , Etanol/farmacologia , Processos Mentais/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Percepção Auditiva/efeitos dos fármacos , Cannabis/administração & dosagem , Ensaios Clínicos como Assunto , Percepção de Cores/efeitos dos fármacos , Túnica Conjuntiva/efeitos dos fármacos , Etanol/administração & dosagem , Etanol/sangue , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Fitoterapia , Placebos , Pulso Arterial/efeitos dos fármacos , Fumar , Estatística como Assunto , Fatores de Tempo , Comportamento Verbal/efeitos dos fármacosAssuntos
Infecções Bacterianas/etiologia , Leucemia/complicações , Doença Aguda , Adulto , Agranulocitose/etiologia , Anemia Aplástica/complicações , Antibacterianos/uso terapêutico , Infecções Bacterianas/prevenção & controle , Clostridium perfringens/isolamento & purificação , Ambiente Controlado , Escherichia coli/isolamento & purificação , Humanos , Mucosa Intestinal/microbiologia , Klebsiella pneumoniae/isolamento & purificação , Proteus/isolamento & purificação , Pseudomonas aeruginosa/isolamento & purificação , Staphylococcus/isolamento & purificaçãoRESUMO
INTRODUCTION: Intramedullary nailing is a standard procedure to treat femoral fractures in patients without polytrauma. Nevertheless, non-union in femoral fractures is a common complication with an incidence of 12.5 percent, mostly arising for mechanical reasons. The aim of this study is to find out whether the increase of stability through an augmentive plate fixation (if necessary with bone grafting) with leaving the nail in situ is adequate to treat the non-union successfully. MATERIALS AND METHODS: Between January 2001 and July 2005 32 patients with femoral non-unions after intramedullary nailing were treated in our hospital. Mean age was 42 years (min 22 and max 75). Distribution of gender was about (2/3) male and (1/3) female. In 17 patients the fractures were localised in the middle of the femur shaft, in 8 patients in the proximal third and in 7 in the distal third. The results were evaluated retrospectively by reviewing the patients' records and X-ray-films. If the success of treatment was not clearly determined through the records the patients were contacted by telephone and, if required, invited for a personal examination. RESULTS: In 29 cases our procedure led primarily to a definite consolidation of the non-union within 5 months on average. The nail was changed eight times, in three patients an additional operation was necessary due to screw breakage. Bone grafting was performed in 27 cases. The overall group included 24 non-smokers and 8 smokers. CONCLUSION: If indicated, the herein demonstrated procedure with an augmentive plate fixation while leaving the nail in situ is simple and safe. Although the intramedullary canal is potentially affected through the initial nailing, the healing of femoral non-unions was observed in the majority of cases in spite of the additional extramedullary approach for plating and bone grafting.
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Placas Ósseas , Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas/instrumentação , Fixação Intramedular de Fraturas/instrumentação , Fraturas Mal-Unidas/cirurgia , Adulto , Idoso , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Fixação Interna de Fraturas/métodos , Fixação Intramedular de Fraturas/métodos , Fraturas Mal-Unidas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Falha de Tratamento , Adulto JovemRESUMO
In a randomized double blind study on acne the efficacy and tolerance of a combination preparation of benzoyl peroxide and miconazole as a cream formulation was compared with those of benzoyl peroxide and oral tetracyclin. For this study, we selected patients mainly suffering from papulopustular acne of medium to high degree of severity. Efficacy and tolerance were satisfactory in both groups, and there was no statistically significant difference.