RESUMEN
Background: By early June 2022, around 300,000 children and adolescents from Ukraine were registered in the German central registry for foreigners.The updated recommendations for action should provide the foundations for an evidence-based and targeted care for the diagnosis and prevention of infectious diseases in underage refugees and asylum seekers, exemplified by Ukraine. Objective: The recommendations for action are intended to support medical personnel in the care of minor refugees in order to1) ensure early recognition and completion of an incomplete vaccination status,2) diagnose and treat common infectious diseases,3) ensure early recognition and treatment of infectious diseases that are rare in the German healthcare system. Material and methods: The recommendations for action were drafted as level 1 (S1) guidelines coordinated by the Association of the Scientific Medical Societies in Germany (AWMF) and were adapted to the situation of refugees from Ukraine.The recommendations were compiled by a representative expert panel appointed by the participating professional societies in an informal consensus and finally officially adopted by the board of directors of all societies concerned. Results: Recommendations are given for the extent of the medical evaluation of minor refugees, including the medical history and physical examination, adapted to the situation of refugees from Ukraine. A blood count and screening for tuberculosis, hepatitis B and C as well as human immunodeficiency virus (HIV) infections are recommended for all minor refugees.For a rapid completion of the vaccination status, an age-related and indications-related prioritization of individual vaccinations will be undertaken. Conclusion: In view of the continuing high numbers of refugees not only from Ukraine, a further professionalization of medical health care is necessary. For this purpose, the necessary structural and personnel framework conditions need to be accomplished.
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The present guideline aims to improve the evidence-based management of children and adolescents with pediatric community-acquired pneumonia (pCAP). Despite a prevalence of approx. 300 cases per 100â000 children per year in Central Europe, mortality is very low. Prevention includes infection control measures and comprehensive immunization. The diagnosis can and should be established clinically by history, physical examination and pulse oximetry, with fever and tachypnea as cardinal features. Additional signs or symptoms such as severely compromised general condition, poor feeding, dehydration, altered consciousness or seizures discriminate subjects with severe pCAP from those with non-severe pCAP. Within an age-dependent spectrum of infectious agents, bacterial etiology cannot be reliably differentiated from viral or mixed infections by currently available biomarkers. Most children and adolescents with non-severe pCAP and oxygen saturation >â92â% can be managed as outpatients without laboratory/microbiology workup or imaging. Anti-infective agents are not generally indicated and can be safely withheld especially in children of young age, with wheeze or other indices suggesting a viral origin. For calculated antibiotic therapy, aminopenicillins are the preferred drug class with comparable efficacy of oral (amoxicillin) and intravenous administration (ampicillin). Follow-up evaluation after 48â-â72 hours is mandatory for the assessment of clinical course, treatment success and potential complications such as parapneumonic pleural effusion or empyema, which may necessitate alternative or add-on therapy.
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Antibacterianos/uso terapéutico , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Neumonía/tratamiento farmacológico , Guías de Práctica Clínica como Asunto , Neumología/normas , Adolescente , Antibacterianos/administración & dosificación , Niño , Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/virología , Europa (Continente) , Alemania , Humanos , Lactante , Neumonía/diagnóstico , Neumonía/virología , Sociedades MédicasRESUMEN
In biodegradation studies with isotope-labelled pesticides, fractions of non-extractable residues (NER) remain, but their nature and composition is rarely known, leading to uncertainty about their risk. Microbial growth leads to incorporation of carbon into the microbial mass, resulting in biogenic NER. Formation of microbial mass can be estimated from the microbial growth yield, but experimental data is rare. Instead, we suggest using prediction methods for the theoretical yield based on thermodynamics. Recently, we presented the Microbial Turnover to Biomass (MTB) method that needs a minimum of input data. We have estimated the growth yield of 40 organic chemicals (31 pesticides) using the MTB and two existing methods. The results were compared to experimental values, and the sensitivity of the methods was assessed. The MTB method performed best for pesticides. Having the theoretical yield and using the released CO2 as a measure for microbial activity, we predicted a range for the formation of biogenic NER. For the majority of the pesticides, a considerable fraction of the NER was estimated to be biogenic. This novel approach provides a theoretical foundation applicable to the evaluation and prediction of biogenic NER formation during pesticide degradation experiments, and may also be employed for the interpretation of NER data from regulatory studies.
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Bacterias/metabolismo , Biomasa , Plaguicidas/metabolismo , Biodegradación Ambiental , Modelos Químicos , Residuos de Plaguicidas/metabolismo , Relación Estructura-Actividad CuantitativaRESUMEN
OBJECTIVE: To generate normative data for the Symbol Digit Modalities Test (SDMT) in Spanish-speaking pediatric populations. METHOD: The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the SDMT as part of a larger neuropsychological battery. SDMT scores were normed using multiple linear regressions and standard deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in the analyses. RESULTS: The final multiple linear regression models showed main effects for age in all countries, such that score increased linearly as a function of age. In addition, age2 had a significant effect in all countries, except in Honduras and Puerto Rico. Models indicated that children whose parent(s) had a MLPE >12 years of education obtained higher score compared to children whose parent(s) had a MLPE ≤12 years for Chile, Guatemala, Mexico, and Spain. Sex affected SDMT score for Paraguay and Spain. CONCLUSIONS: This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate interpretation of the SDMT with pediatric populations.
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Pruebas Neuropsicológicas/normas , Niño , Humanos , América Latina , Modelos LinealesRESUMEN
Child and adolescent refugees in Germany represent a particularly vulnerable social group and treating infectious diseases forms a crucial part of providing their medical care. From an infectious diseases perspective, refugees themselves, as a result of their difficult personal circumstances, are the ones at highest risk. Even in crisis situations, medical practitioners are medically and ethically obliged to provide a high standard of care. The guidelines presented here propose recommendations for diagnosing and preventing infectious diseases among refugees under 18 in Germany. The guidelines are intended to assist in optimizing vaccine protection and treatment of diseases while taking into consideration factors such as refugees' challenging living conditions, cultural differences and potential language barriers.Upon refugees' arrival at the first housing sites, it is recommended that a basic clinical screening (and not just a brief visual inspection) be provided in order to identify and initiate treatment for acute medical problems and potentially contagious diseases (including tuberculosis), as well as to close gaps in vaccination coverage. Documentation of the clinical findings is critical, both to avoid redundant investigations and to optimize individual medical care. For this, an effective communication system must be established.Once refugees have been transferred into their destination community, outpatient and inpatient care providers should collaborate to bring refugees up-to-date with all vaccines recommended by STIKO (German Standing Committee on Vaccination). The same high standard of medical care should be delivered to refugees as would be to the general population. Due to the high prevalence of multi-resistant organisms (MRO) in the refugees' countries of origin, MRO screening is recommended for most patients receiving inpatient care.
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Control de Enfermedades Transmisibles/normas , Enfermedades Transmisibles/diagnóstico , Enfermedades Transmisibles/terapia , Exámenes Obligatorios/normas , Guías de Práctica Clínica como Asunto , Refugiados , Barreras de Comunicación , Alemania , Accesibilidad a los Servicios de Salud/normas , Humanos , Vacunación Masiva/normasRESUMEN
BACKGROUND: The Test of Memory Malingering (TOMM) is an instrument used to assess purposeful embellishment or fabrication of memory difficulties for personal gain. Although the TOMM can be use in non-English speaking cultures, it has not been validated in Spanish-speaking Central and South American contexts. OBJECTIVE: To generate normative data on TOMM across 7 countries in Latin America, with country-specific adjustments for gender, age, and education, where appropriate. METHOD: The sample consisted of 2,266 healthy adults who were recruited from Argentina, Bolivia, Chile, Mexico, Paraguay, Peru, and Puerto Rico. Each subject was administered the TOMM as part of a larger neuropsychological battery. A standardized five-step statistical procedure was used to generate the norms. RESULTS: t-tests did not show significant differences in TOMM performance between men and women in any countries of the TOMM Trial 1 or 2. As a result, gender-adjusted norms were not generated. CONCLUSIONS: The results from this study will have a large impact on the practice of neuropsychology in Latin America, as this is the first normative multicenter study to create norms for the TOMM in this global region.
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Simulación de Enfermedad/diagnóstico , Simulación de Enfermedad/psicología , Trastornos de la Memoria/diagnóstico , Trastornos de la Memoria/psicología , Pruebas Neuropsicológicas/normas , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Escolaridad , Femenino , Humanos , Lenguaje , América Latina , Masculino , Persona de Mediana Edad , Valores de Referencia , Análisis de Regresión , Factores Sexuales , Factores Socioeconómicos , Adulto JovenRESUMEN
BACKGROUND: Schmallenberg virus (SBV) is an emerging Orthobunyavirus of ruminant livestock species currently circulating in Europe. SBV causes a subclinical or mild disease in adult animals but vertical transmission to pregnant dams may lead to severe malformations in the offspring. Data on the onset of clinical signs, viremia and seroconversion in experimentally infected adult animals are available for cattle and sheep but are still lacking for goats. For a better understanding of the pathogenesis of SBV infection in adult ruminants, we carried out experimental infections in adult goats. Our specific objectives were: (i) to record clinical signs, viremia and seroconversion; (ii) to monitor viral excretion in the semen of infected bucks; (iii) to determine in which tissues SBV replication took place and virus-induced lesions developed. RESULTS: Four goats and two bucks were inoculated with SBV. Virus inoculation was followed by a short viremic phase lasting 3 to 4 days and a seroconversion occurring between days 7 and 14 pi in all animals. The inoculated goats did not display any clinical signs, gross lesions or histological lesions. Viral genomic RNA was found in one ovary but could not be detected in other organs. SBV RNA was not found in the semen samples collected from two inoculated bucks. CONCLUSIONS: In the four goats and two bucks, the kinetics of viremia and seroconversion appeared similar to those previously described for sheep and cattle. Our limited set of data provides no evidence of viral excretion in buck semen.
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Infecciones por Bunyaviridae/veterinaria , Enfermedades de las Cabras/virología , Orthobunyavirus/aislamiento & purificación , Animales , Infecciones por Bunyaviridae/epidemiología , Infecciones por Bunyaviridae/virología , Ensayo de Inmunoadsorción Enzimática , Cabras , Masculino , ARN Viral/sangre , ARN Viral/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinariaRESUMEN
Overall dissipation of pesticides from plants is frequently measured, but the contribution of individual loss processes is largely unknown. We use a pesticide fate model for the quantification of dissipation by processes other than degradation. The model was parameterised using field studies. Scenarios were established for Copenhagen/Denmark and Shanghai/PR China, and calibrated with measured results. The simulated dissipation rates of 42 pesticides were then compared with measured overall dissipation from field studies using tomato and wheat. The difference between measured overall dissipation and calculated dissipation by non-degradative processes should ideally be contributable to degradation in plants. In 11% of the cases, calculated dissipation was above the measured dissipation. For the remaining cases, the non-explained dissipation ranged from 30% to 83%, depending on crop type, plant part and scenario. Accordingly, degradation is the most relevant dissipation process for these 42 pesticides, followed by growth dilution. Volatilisation was less relevant, which can be explained by the design of plant protection agents. Uptake of active compound from soil into plants leads to a negative dissipation process (i.e. a gain) that is difficult to quantify because it depends largely on interception, precipitation and plant stage. This process is particularly relevant for soluble compounds.
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Plaguicidas/metabolismo , Plantas/metabolismo , Biodegradación Ambiental , China , Dinamarca , Semivida , Solanum lycopersicum/metabolismo , Modelos Biológicos , Residuos de Plaguicidas/química , Residuos de Plaguicidas/metabolismo , Plaguicidas/química , Triticum/metabolismo , VolatilizaciónRESUMEN
Glucagon-like peptide-1 (GLP-1) affects central autonomic neurons, including those controlling the cardiovascular system, thermogenesis, and energy balance. Preproglucagon (PPG) neurons, located mainly in the nucleus tractus solitarius (NTS) and medullary reticular formation, produce GLP-1. In transgenic mice expressing glucagon promoter-driven yellow fluorescent protein (YFP), these brainstem PPG neurons project to many central autonomic regions where GLP-1 receptors are expressed. The spinal cord also contains GLP-1 receptor mRNA but the distribution of spinal PPG axons is unknown. Here, we used two-color immunoperoxidase labeling to examine PPG innervation of spinal segments T1-S4 in YFP-PPG mice. Immunoreactivity for YFP identified spinal PPG axons and perikarya. We classified spinal neurons receiving PPG input by immunoreactivity for choline acetyltransferase (ChAT), nitric oxide synthase (NOS) and/or Fluorogold (FG) retrogradely transported from the peritoneal cavity. FG microinjected at T9 defined cell bodies that supplied spinal PPG innervation. The deep dorsal horn of lower lumbar cord contained YFP-immunoreactive neurons. Non-varicose, YFP-immunoreactive axons were prominent in the lateral funiculus, ventral white commissure and around the ventral median fissure. In T1-L2, varicose, YFP-containing axons closely apposed many ChAT-immunoreactive sympathetic preganglionic neurons (SPN) in the intermediolateral cell column (IML) and dorsal lamina X. In the sacral parasympathetic nucleus, about 10% of ChAT-immunoreactive preganglionic neurons received YFP appositions, as did occasional ChAT-positive motor neurons throughout the rostrocaudal extent of the ventral horn. YFP appositions also occurred on NOS-immunoreactive spinal interneurons and on spinal YFP-immunoreactive neurons. Injecting FG at T9 retrogradely labeled many YFP-PPG cell bodies in the medulla but none of the spinal YFP-immunoreactive neurons. These results show that brainstem PPG neurons innervate spinal autonomic and somatic motor neurons. The distributions of spinal PPG axons and spinal GLP-1 receptors correlate well. SPN receive the densest PPG innervation. Brainstem PPG neurons could directly modulate sympathetic outflow through their spinal inputs to SPN or interneurons.
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Fibras Adrenérgicas , Axones/metabolismo , Bulbo Raquídeo/citología , Neuronas Motoras/citología , Células del Asta Posterior/citología , Proglucagón/metabolismo , Fibras Adrenérgicas/metabolismo , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Colina O-Acetiltransferasa/metabolismo , Femenino , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Técnicas para Inmunoenzimas , Interneuronas/citología , Interneuronas/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Masculino , Bulbo Raquídeo/metabolismo , Ratones Transgénicos , Neuronas Motoras/metabolismo , Técnicas de Trazados de Vías Neuroanatómicas , Óxido Nítrico Sintasa/metabolismo , Cavidad Peritoneal/inervación , Células del Asta Posterior/metabolismo , Proglucagón/genética , Sacro , Estilbamidinas , Vértebras TorácicasRESUMEN
BACKGROUND: This qualitative, exploratory study examines the content of communication between healthcare providers (HCP) and childhood cancer patients (CCP) during a medical appointment to evaluate the extent to which cancer survivorship issues (medical and psychosocial) are discussed. METHODS: The content of the communication for 16 CCP ages 10-22 and their HCP were examined via audio recorded medical appointments occurring within 6 months of the end of active cancer treatment. The data were analysed using template analysis, a constructivist-interpretivist qualitative approach. RESULTS: HCP addressed more medically focused than psychosocially focused issues related to survivorship. CONCLUSIONS: Most discussions of survivorship are medically focused, potentially leaving patients with little information about future psychosocial functioning. Recommendations for future research on enhancing discussions about psychosocial issues are presented. This research has the potential to inform future interventions to enhance patient-provider communication on survivorship issues.
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Comunicación , Neoplasias/psicología , Relaciones Profesional-Paciente , Sobrevivientes/psicología , Adolescente , Niño , Femenino , Humanos , Masculino , Investigación Cualitativa , Estados Unidos , Adulto JovenRESUMEN
Preproglucagon (PPG) neurons produce glucagon-like peptide-1 (GLP-1) and occur primarily in the nucleus tractus solitarius (NTS). GLP-1 affects a variety of central autonomic circuits, including those controlling the cardiovascular system, thermogenesis, and most notably energy balance. Our immunohistochemical studies in transgenic mice expressing YFP under the control of the PPG promoter showed that PPG neurons project widely to central autonomic regions, including brainstem nuclei. Functional studies have highlighted the importance of hindbrain receptors for the anorexic effects of GLP-1. In this study, we assessed YFP innervation of neurochemically identified brainstem neurons in transgenic YFP-PPG mice. Immunoreactivity for YFP plus choline acetyltransferase (ChAT), tyrosine hydroxylase (TH) and/or serotonin (5-HT) was visualised with two- or three-colour immunoperoxidase labelling using black (YFP), brown and blue-grey reaction products. In the dorsal motor nucleus of the vagus (DMV), terminals from fine YFP-immunoreactive axons closely apposed a small proportion of ChAT-positive and rare TH-positive/ChAT-positive motor neurons, mostly ventral to AP. YFP-immunoreactive innervation was virtually absent from the compact and loose formations of the nucleus ambiguus. In the NTS, some TH-immunoreactive neurons were closely apposed by YFP-containing axons. In the A1/C1 column in the ventrolateral medulla, close appositions on TH-positive neurons were more common, particularly in the caudal portion of the column. A single YFP-immunoreactive axon usually provided 1-3 close appositions on individual ChAT- or TH-positive neurons. Serotonin-immunoreactive neurons were most heavily innervated, with the majority of raphé pallidus, raphé obscurus and parapyramidal neurons receiving several close appositions from large varicosities of YFP-immunoreactive axons. These results indicate that GLP-1 neurons innervate various populations of brainstem autonomic neurons. These include vagal efferent neurons and catecholamine neurons in areas linked with cardiovascular control. Our data also indicate a synaptic connection between GLP-1 neurons and 5-HT neurons, some of which might contribute to the regulation of appetite.
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Sistema Nervioso Autónomo/metabolismo , Tronco Encefálico/metabolismo , Neuronas/metabolismo , Proglucagón/metabolismo , Animales , Vías Autónomas/metabolismo , Colina O-Acetiltransferasa/metabolismo , Femenino , Masculino , Ratones , Vías Nerviosas/metabolismo , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Chlorinated ethenes (CE) are among the most frequent contaminants of soil and groundwater in the Czech Republic. Because conventional methods of subsurface contamination investigation are costly and technically complicated, attention is directed on alternative and innovative field sampling methods. One promising method is sampling of tree cores (plugs of woody tissue extracted from a host tree). Volatile organic compounds can enter into the trunks and other tissues of trees through their root systems. An analysis of the tree core can thus serve as an indicator of the subsurface contamination. Four areas of interest were chosen at the experimental site with CE groundwater contamination and observed fluctuations in groundwater concentrations. CE concentrations in groundwater and tree cores were observed for a 1-year period. The aim was to determine how the CE concentrations in obtained tree core samples correlate with the level of contamination of groundwater. Other factors which can affect the transfer of contaminants from groundwater to wood were also monitored and evaluated (e.g., tree species and age, level of groundwater table, river flow in the nearby Ploucnice River, seasonal effects, and the effect of the remediation technology operation). Factors that may affect the concentration of CE in wood were identified. The groundwater table level, tree species, and the intensity of transpiration appeared to be the main factors within the framework of the experiment. Obtained values documented that the results of tree core analyses can be used to indicate the presence of CE in the subsurface. The results may also be helpful to identify the best sampling period for tree coring and to learn about the time it takes until tree core concentrations react to changes in groundwater conditions. Interval sampling of tree cores revealed possible preservation of the contaminant in the wood of trees.
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Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Agua Subterránea/análisis , Hidrocarburos Clorados/análisis , Árboles/química , República ChecaRESUMEN
Models for the prediction of chemical uptake into plants are widely applied tools for human and wildlife exposure assessment, pesticide design and for environmental biotechnology such as phytoremediation. Steady-state considerations are often applied, because they are simple and have a small data need. However, often the emission pattern is non-steady. Examples are pesticide spraying, or the application of manure and sewage sludge on agricultural fields. In these scenarios, steady-state solutions are not valid, and dynamic simulation is required. We compared different approaches for dynamic modelling of plant uptake in order to identify relevant processes and timescales of processes in the soil-plant-air system. Based on the outcome, a new model concept for plant uptake models was developed, approximating logistic growth and coupling transpiration to growing plant mass. The underlying system of differential equations was solved analytically for the inhomogenous case, i.e. for constant input. By superposition of the results of n periods, changes in emission and input data between periods are considered. This combination allows to mimic most input functions that are relevant in practice. The model was set up, parameterized and tested for uptake into growing crops. The outcome was compared with a numerical solution, to verify the mathematical structure.
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Contaminantes Ambientales/farmacocinética , Modelos Biológicos , Plantas/metabolismo , Medición de Riesgo/métodos , Compuestos Orgánicos/farmacocinética , Plaguicidas/farmacocinética , Desarrollo de la Planta , Aguas del Alcantarillado/químicaRESUMEN
Glucagon-like peptide 1 (GLP-1) and its analogue exendin-4 inhibit food intake, reduce blood glucose levels and increase blood pressure and heart rate by acting on GLP-1 receptors in many brain regions. Within the CNS, GLP-1 is produced only by preproglucagon (PPG) neurons. We suggest that PPG neurons mediate the central effects of GLP-1 by modulating sympathetic and vagal outflow. We therefore analysed the projections of PPG neurons to brain sites involved in autonomic control. In transgenic mice expressing yellow fluorescent protein (YFP) under the control of the PPG promoter, we assessed YFP-immunoreactive innervation using an anti-GFP antiserum and avidin-biotin-peroxidase. PPG neurons were intensely YFP-immunoreactive and axons could be easily discriminated from dendrites. YFP-immunoreactive cell bodies occurred primarily within the caudal nucleus tractus solitarius (NTS) with additional somata ventral to the hypoglossal nucleus, in raphé obscurus and in the intermediate reticular nucleus. The caudal NTS contained a dense network of dendrites, some of which extended into the area postrema. Immunoreactive axons were widespread throughout NTS, dorsal vagal nucleus and reticular nucleus with few in the hypoglossal nucleus and pyramids. The dorsomedial and paraventricular hypothalamic nuclei, ventrolateral periaqueductal grey and thalamic paraventricular nucleus exhibited heavy innervation. The area postrema, rostral ventrolateral medulla, pontine central grey, locus coeruleus/Barrington's nucleus, arcuate nucleus and the vascular organ of the lamina terminalis were moderately innervated. Only a few axons occurred in the amygdala and subfornical organ. Our results demonstrate that PPG neurons innervate primarily brain regions involved in autonomic control. Thus, central PPG neurons are ideally situated to modulate sympathetic and parasympathetic outflow through input at a variety of central sites. Our data also highlight that immunohistochemistry improves detection of neurons expressing YFP. Hence, animals in which specific populations of neurons have been genetically-modified to express fluorescent proteins are likely to prove ideal for anatomical studies.
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Sistema Nervioso Autónomo/citología , Encéfalo/citología , Vías Nerviosas/citología , Neuronas/citología , Proglucagón/metabolismo , Animales , Sistema Nervioso Autónomo/metabolismo , Encéfalo/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Masculino , Ratones , Ratones Transgénicos , Vías Nerviosas/metabolismo , Neuronas/metabolismoRESUMEN
The New Model Framework (NMF) for uptake into crops is based on particle deposition and Transfer factors from soil to plant calculated from the BAse de donnees sur les teneurs en Elements Traces metalliques de Plantes Potageres (BAPPET) database. Besides NMF, approaches developed by the National Institute of Public Health and the Environment (RIVM), Hough, and the United States Environmental Protection Agency (US EPA), and the Contaminated Land Exposure Assessment (CLEA) approach were tested. Experimental data were assembled from the BAPPET database and Danish background data of As, Cd and Pb in soil, air and crops was collected. None of the models proved able to estimate the measured concentrations in plants from the BAPPET database with an absolute normalized error smaller than 70%. On average, the predictions had an error of 80-250%. However, when applying the models to the rural Danish background scenario, the NMF and other models predicted the concentrations in carrot and lettuce within the range of measured values. Regressions considering soil pH, organic matter and clay content were not superior to simple transfer factors. The transfer from air to plant is significant, at least under background conditions, and should be considered in the prediction methods.
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Arsénico/metabolismo , Cadmio/metabolismo , Daucus carota/metabolismo , Ecotoxicología/métodos , Lactuca/metabolismo , Plomo/metabolismo , Contaminantes del Suelo/metabolismo , Modelos Estadísticos , Suelo/análisisRESUMEN
4-chlorophenol (4-CP) is a well-known hazardous chlorinated compound and a precursor for the synthesis of the herbicide 2,4-dichlorophenoxyacetate. The relation between uptake, accumulation, toxicity, and removal of 4-CP in willow trees (Salix viminalis) was determined. In addition, the feasibility of implementing phytoremediation as a treatment method for 4-CP contamination was investigated. Willows were exposed to 4-CP levels < or =79.9 mg/L in hydroponic solution. The transpiration of the trees was used to determine toxic effects. Almost no inhibition of transpiration was detected at concentrations > or =15 mg/L. For concentrations > or =37.3 mg/L, transpiration decreased to < or =50%, and the trees wilted. Trees exposed to 79.9 mg/L wilted and eventually died. For concentrations of 79.9 mg/L, a significantly higher amount of 4-CP remained at the end of experiments in the test system compared with the amount remaining at all other concentrations. The loss of chemical from the system in experiments with trees was high, < or =99.5%. In treeless experiments, the mass loss of 4-CP was only 6% to 10%. The results indicated that degradation in the root zone is the main reason for the removal of 4-CP from the media. Phytoremediation of 4-CP in willow trees seems to be a remediation option, especially at concentrations <37.3 mg/L, at which point degradation of 4-CP is rapid and efficient, and the toxic effects on trees are not lethal.
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Clorofenoles/toxicidad , Salix/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Biodegradación Ambiental , Clorofenoles/metabolismo , Relación Dosis-Respuesta a Droga , Concentración 50 Inhibidora , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Transpiración de Plantas/efectos de los fármacos , Salix/metabolismo , Contaminantes Químicos del Agua/metabolismoRESUMEN
The current European risk assessment for chemicals considers only tap water, while in reality other beverages play an important role. A good part of beverages are made from fruits, for example apple juice and vine. A mathematical model was developed to predict uptake of neutral organic chemicals from soil and air into fruits. The new fruit tree model considers eight compartments, i.e. two soil compartments, fine roots, thick roots, stem, leaves, fruits, and air. Chemical equilibrium, advective transport in xylem and phloem, diffusive exchange to soil and air and growth dilution are the main processes. The parameterization is for a square-meter of an apple orchard. The model predicts that polar, non-volatile compounds will effectively be transported from soil to fruits, while lipophilic compounds will preferably accumulate from air into fruits. Results from various experiments show no disagreement with the model predictions.
Asunto(s)
Contaminantes Atmosféricos/metabolismo , Frutas/metabolismo , Modelos Biológicos , Contaminantes del Suelo/metabolismo , Contaminantes Atmosféricos/química , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente , Malus/metabolismo , Modelos Químicos , Compuestos Orgánicos/metabolismo , Floema/metabolismo , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Tallos de la Planta/metabolismo , Medición de Riesgo , Contaminantes del Suelo/química , Xilema/metabolismoRESUMEN
Weanling pigs with mean initial BW of 6.04 kg (Exp.1) and 5.65 kg (Exp. 2) and mean age at weaning of 18.2 d (Exp. 1) and 17.7 d (Exp. 2) were used in two 5-wk experiments (Exp. 1, n = 180; Exp. 2, n = 300) to evaluate the effects of an organic acid blend (Acid LAC, Kemin Americas Inc., Des Moines, IA) and an inorganic/organic acid blend (Kem-Gest, Kemin Americas Inc.) on weanling pig growth performance and microbial shedding. In Exp. 1, the 5 dietary treatments were 1) negative control, 2) diet 1 + 55 ppm carbadox, 3) diet 1 + 0.4% Acid LAC, 4) diet 1 + 0.2% Kem-Gest, 5) diet 1 + 0.4% Acid LAC and 0.2% Kem-Gest. In Exp. 2, the 6 dietary treatments were diets 1 through 4 corresponding to Exp. 1, plus 5) sequence 1: 0.4% Acid LAC for 7 d followed by 0.2% Kem-Gest for 28 d, and 6) sequence 2: 0.2% Kem-Gest for 7 d followed by 0.4% Acid LAC for 28 d. Pigs were housed at 6 (Exp. 1) or 10 (Exp. 2) pigs/pen. Treatments were fed throughout the experiment in 3 phases: d 0 to 7, d 7 to 21, and d 21 to 35. In Exp. 1, there were no differences (P > 0.05) in ADG, ADFI, or G:F among the dietary treatments at any time during the study. In Exp. 2, throughout the study, pigs fed carbadox (diet 2) and sequence 1 (diet 5) diets had the greatest ADG (d 0 to 35; 262, 294, 257, 257, 292, and 261 g/d, diets 1 through 6, respectively; P < 0.05), greater ADFI than all other acid treatments (P < 0.05), and tended to have greater ADFI than diet 1 (P < 0.10). Fecal pH, Escherichia coli concentrations, and Salmonella presence were determined at d 6, 20, and 34 for Exp. 1, and on d 32 for Exp. 2. For both experiments, there was no effect of treatment on the presence of fecal Salmonella (P > 0.10) at any sampling time. In Exp. 1, fecal E. coli concentrations for pigs fed the carbadox (P < 0.05) diet were greater than for pigs fed the combination diet with 0.4% Acid LAC and 0.2% Kem-Gest on d 34, and the pigs fed the negative control diet tended (P < 0.10) to have greater fecal E. coli concentrations than those fed the combination diet on d 34. In Exp. 2, fecal pH of pigs fed sequence 1 tended to be greater than fecal pH of pigs fed diet 1, diet 4, or sequence 2 (P < 0.10), but there was no dietary effect on fecal E. coli. In Exp. 1, growth performance of pigs fed the Acid LAC and Kem-Gest diets was similar to each other and to that of the carbadox-fed pigs. Adding the combination of 0.4% Acid LAC and 0.2% Kem-Gest to nursery pig diets reduced ADFI and pig growth rate. In Exp. 2, pigs fed the acid sequence of Acid LAC-Kem-Gest had similar growth performance to pigs fed carbadox, and this novel dietary acid sequence may have merit as a replacement for antibiotics in the nursery phase.
Asunto(s)
Alimentación Animal , Dieta/veterinaria , Infecciones por Escherichia coli/veterinaria , Salmonelosis Animal/microbiología , Enfermedades de los Porcinos/microbiología , Porcinos/fisiología , Alimentación Animal/análisis , Animales , Carbadox/administración & dosificación , Carbadox/farmacología , Ingestión de Alimentos/fisiología , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Heces/química , Heces/microbiología , Concentración de Iones de Hidrógeno , Salmonella/aislamiento & purificación , Porcinos/crecimiento & desarrollo , Porcinos/microbiología , Factores de Tiempo , Destete , Aumento de Peso/efectos de los fármacos , Aumento de Peso/fisiologíaRESUMEN
Cr release overtime was investigated in batch experiments for eleven air-pollution-control residues from eight different municipal solid waste incinerators covering all majorflue gas cleaning technologies. Cr released during 168 h of contact with water showed significant variations among the residues studied. Also for the individual residue, large variations were observed depending on the liquid-to-solid ratio used in the leaching test and the degree of carbonation. It is argued that Al(0) present in the residues can control Cr leaching by reducing Cr(VI) released from the solid phase by dissolution and that exposure to oxygen-either prior to or during the leaching test-depletes the reduction capacity of Al(0) leading to increased Cr leaching. A dynamic model is shown to describe Cr release from all investigated residues by accounting for Al(0) oxidation with Cr(VI), O2, and water as well as Cr(VI) dissolution. The paper reveals that Al-O2-Cr(VI) interactions must be considered very carefully when interpreting Cr leaching data.