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Biological soil crusts (biocrusts) release the reactive nitrogen gases (Nr) nitrous acid (HONO) and nitric oxide (NO) into the atmosphere, but the underlying microbial process controls have not yet been resolved. In this study, we analyzed the activity of microbial consortia relevant in Nr emissions during desiccation using transcriptome and proteome profiling and fluorescence in situ hybridization. We observed that < 30 min after wetting, genes encoding for all relevant nitrogen (N) cycling processes were expressed. The most abundant transcriptionally active N-transforming microorganisms in the investigated biocrusts were affiliated with Rhodobacteraceae, Enterobacteriaceae, and Pseudomonadaceae within the Alpha- and Gammaproteobacteria. Upon desiccation, the nitrite (NO2-) content of the biocrusts increased significantly, which was not the case when microbial activity was inhibited. Our results confirm that NO2- is the key precursor for biocrust emissions of HONO and NO. This NO2- accumulation likely involves two processes related to the transition from oxygen-limited to oxic conditions in the course of desiccation: (i) a differential regulation of the expression of denitrification genes; and (ii) a physiological response of ammonia-oxidizing organisms to changing oxygen conditions. Thus, our findings suggest that the activity of N-cycling microorganisms determines the process rates and overall quantity of Nr emissions.
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Ácido Nitroso , Suelo , Hibridación Fluorescente in Situ , Óxido Nítrico , Nitrógeno/análisis , Dióxido de Nitrógeno , Ácido Nitroso/metabolismo , Óxido Nitroso/análisis , Oxígeno , Microbiología del Suelo , Agua/metabolismoRESUMEN
Aerosols interact with radiation and clouds. Substantial progress made over the past 40 years in observing, understanding, and modeling these processes helped quantify the imbalance in the Earth's radiation budget caused by anthropogenic aerosols, called aerosol radiative forcing, but uncertainties remain large. This review provides a new range of aerosol radiative forcing over the industrial era based on multiple, traceable, and arguable lines of evidence, including modeling approaches, theoretical considerations, and observations. Improved understanding of aerosol absorption and the causes of trends in surface radiative fluxes constrain the forcing from aerosol-radiation interactions. A robust theoretical foundation and convincing evidence constrain the forcing caused by aerosol-driven increases in liquid cloud droplet number concentration. However, the influence of anthropogenic aerosols on cloud liquid water content and cloud fraction is less clear, and the influence on mixed-phase and ice clouds remains poorly constrained. Observed changes in surface temperature and radiative fluxes provide additional constraints. These multiple lines of evidence lead to a 68% confidence interval for the total aerosol effective radiative forcing of -1.6 to -0.6 W m-2, or -2.0 to -0.4 W m-2 with a 90% likelihood. Those intervals are of similar width to the last Intergovernmental Panel on Climate Change assessment but shifted toward more negative values. The uncertainty will narrow in the future by continuing to critically combine multiple lines of evidence, especially those addressing industrial-era changes in aerosol sources and aerosol effects on liquid cloud amount and on ice clouds.
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OBJECTIVE: Human patients with Duchenne muscular dystrophy (DMD) commonly exhibit a short stature, but the pathogenesis of this growth retardation is not completely understood. Due to the suspected involvement of the growth hormone/insulin-like growth factor 1 (GH/IGF1) system, controversial therapeutic approaches have been developed, including both GH- administration, as well as GH-inhibition. In the present study, we examined relevant histomorphological and ultrastructural features of adenohypophyseal GH-producing somatotroph cells in a porcine DMD model. METHODS: The numbers and volumes of immunohistochemically labelled somatotroph cells were determined in consecutive semi-thin sections of plastic resin embedded adenohypophyseal tissue samples using unbiased state-of-the-art quantitative stereological analysis methods. RESULTS: DMD pigs displayed a significant growth retardation, accounting for a 55% reduction of body weight, accompanied by a significant 50% reduction of the number of somatotroph cells, as compared to controls. However, the mean volumes of somatotroph cells and the volume of GH-granules per cell were not altered. Western blot analyses of the adenohypophyseal protein samples showed no differences in the relative adenohypophyseal GH-abundance between DMD pigs and controls. CONCLUSION: The findings of this study do not provide evidence for involvement of somatotroph cells in the pathogenesis of growth retardation of DMD pigs. These results are in contrast with previous findings in other dystrophin-deficient animal models, such as the golden retriever model of Duchenne muscular dystrophy, where increased mean somatotroph cell volumes and elevated volumes of intracellular GH-granules were reported and associated with DMD-related growth retardation. Possible reasons for the differences of somatotroph morphology observed in different DMD models are discussed.
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Trastornos del Crecimiento/patología , Hormona del Crecimiento/metabolismo , Distrofia Muscular de Duchenne/patología , Vesículas Secretoras/patología , Somatotrofos/patología , Animales , Animales Modificados Genéticamente , Recuento de Células , Modelos Animales de Enfermedad , Distrofina/genética , Trastornos del Crecimiento/complicaciones , Trastornos del Crecimiento/metabolismo , Microscopía Electrónica , Distrofia Muscular de Duchenne/complicaciones , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Tamaño de los Órganos , Hipófisis/patología , Hipófisis/ultraestructura , Adenohipófisis/patología , Adenohipófisis/ultraestructura , Vesículas Secretoras/ultraestructura , Somatotrofos/ultraestructura , PorcinosRESUMEN
In an anonymous 4-person economic game, participants contributed more money to a common project (i.e., cooperated) when required to decide quickly than when forced to delay their decision (Rand, Greene & Nowak, 2012), a pattern consistent with the social heuristics hypothesis proposed by Rand and colleagues. The results of studies using time pressure have been mixed, with some replication attempts observing similar patterns (e.g., Rand et al., 2014) and others observing null effects (e.g., Tinghög et al., 2013; Verkoeijen & Bouwmeester, 2014). This Registered Replication Report (RRR) assessed the size and variability of the effect of time pressure on cooperative decisions by combining 21 separate, preregistered replications of the critical conditions from Study 7 of the original article (Rand et al., 2012). The primary planned analysis used data from all participants who were randomly assigned to conditions and who met the protocol inclusion criteria (an intent-to-treat approach that included the 65.9% of participants in the time-pressure condition and 7.5% in the forced-delay condition who did not adhere to the time constraints), and we observed a difference in contributions of -0.37 percentage points compared with an 8.6 percentage point difference calculated from the original data. Analyzing the data as the original article did, including data only for participants who complied with the time constraints, the RRR observed a 10.37 percentage point difference in contributions compared with a 15.31 percentage point difference in the original study. In combination, the results of the intent-to-treat analysis and the compliant-only analysis are consistent with the presence of selection biases and the absence of a causal effect of time pressure on cooperation.
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Conducta Cooperativa , Heurística , Relaciones Interpersonales , Toma de Decisiones , Humanos , Intención , Modelos PsicológicosRESUMEN
OBJECTIVES: Tigecycline represents one of the last-line therapeutics to combat multidrug-resistant bacterial pathogens, including VRE and MRSA. The German National Reference Centre for Staphylococci and Enterococci has received 73 tigecycline-resistant Enterococcus faecium and Enterococcus faecalis isolates in recent years. The precise mechanism of how enterococci become resistant to tigecycline remains undetermined. This study documents an analysis of the role of efflux pumps in tigecycline resistance in clinical isolates of Enterococcus spp. METHODS: Various tigecycline MICs were found for the different isolates analysed. Tigecycline-resistant strains were analysed with respect to genome and transcriptome differences by means of WGS and RT-qPCR. Genes of interest were cloned and expressed in Listeria monocytogenes for verification of their functionality. RESULTS: Detailed comparative whole-genome analyses of three isogenic strains, showing different levels of tigecycline resistance, revealed the major facilitator superfamily (MFS) efflux pump TetL and the ribosomal protection protein TetM as possible drug resistance proteins. Subsequent RT-qPCR confirmed up-regulation of the respective genes. A correlation of gene copy number and level of MIC was inferred from further qPCR analyses. Expression of both tet(L) and tet(M) in L. monocytogenes unequivocally demonstrated the potential to increase tigecycline MICs upon acquisition of either locus. CONCLUSIONS: Our results indicate that increased expression of two tetracycline resistance determinants, a tet(L)-encoded MFS pump and a tet(M)-encoded ribosomal protection protein, is capable of conferring tigecycline resistance in enterococcal clinical isolates.
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Antibacterianos/farmacología , Proteínas Bacterianas/genética , Farmacorresistencia Microbiana/genética , Enterococcus faecium/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Minociclina/análogos & derivados , Plásmidos/genética , Secuencia de Bases , Enterococcus faecium/genética , Dosificación de Gen , Infecciones por Bacterias Gramnegativas/microbiología , Pruebas de Sensibilidad Microbiana , Minociclina/farmacología , Reacción en Cadena de la Polimerasa , Resistencia a la Tetraciclina/genética , Tigeciclina , Regulación hacia Arriba/genéticaRESUMEN
The formation of adipocere slows further decomposition and preserves corpses for decades or even centuries. This resistance to degradation is a serious problem, especially with regard to the reuse of graves after regular resting times. We present results from an exhumation series in modern graveyards where coffins from water-saturated earth graves contained adipocere embedded in black humic material after resting times of about 30 years. Based on the assumption that this humic material resulted from in situ degradation of adipocere, its presence contradicts the commonly held opinion that adipocere decomposition only occurs under aerobic conditions. To test our hypothesis, we collected black humic material, adipocere as well as soil samples above and below coffins from representative graves (n=7). A comprehensive chemical analysis of the samples substantiated our in situ degradation theory. Element compositions and fatty acid mass spectra confirmed that the humic black material originated from the corpses. A van Krevelen diagram classified the excavated adipocere material as lipid, whereas the black humic material was closer to the carbohydrate region. Mass fragmentograms of the humic material revealed the presence of large amounts of saturated vs. unsaturated nC16 and nC18 fatty acids, which is typical for adipocere. In addition, the soil samples exhibited a lipid signature deriving primarily from plant waxes and root components (C20C32). Solid-state (13)C NMR spectra of adipocere displayed well-resolved signals of saturated aliphatic chains and a signal that corresponded to carboxylic acid groups. The NMR spectra of the black humic material revealed signals characteristic of long aliphatic chains. The intensities varied in relation to the state of degradation of the sample, as did the signals of oxidized aliphatic chains, acetals and ketals, aromatic structures, esters and amids. The analyses confirmed that the black humic material was indeed derived from adipocere, so the assumption is that the components detected must have developed from aliphatic fatty acids via a number of oxidation and condensation processes. We therefore propose the existence of chemical pathway(s) for the degradation of adipocere under poikiloaerobic conditions. Possible (biogeo)chemical reaction chains include (1) the autoxidation of fatty acids enhanced by haemoglobin, methaemoglobin and haemin, (2) the use of alternative electron acceptors, which leads to the formation of H2S that then reacts abiotically with iron (from haemoglobin), rendering iron sulphide, and (3) the Maillard reaction. These findings are another step forward in understanding the chemistry of buried corpses.
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Entierro , Cambios Post Mortem , Suelo/química , Carbohidratos/análisis , Cementerios , Exhumación , Ácidos Grasos/análisis , Humanos , Lípidos/análisis , Espectroscopía de Resonancia MagnéticaRESUMEN
BACKGROUND AND INTRODUCTION: The duration of inability for work according to work load and the rate of successful return to work after open and arthroscopic Bankart repair (BR) due to anterior shoulder dislocation has not yet been examined with regard to validated work strain by the REFA classification. Thus, the objective of this study was to determine the duration of inability to work according to work load (REFA criteria) after open and arthroscopic BR as well as the rate of successful return to the original occupation. PATIENTS AND METHODS: A total of 93 patients (20 f/73 m) with isolated anterior arthroscopic or open BR due to posttraumatic anterior shoulder instability with no items of hyperlaxity were included in this study. There were 72 patients with arthroscopic and 21 patients with open BR. The postoperative aftercare was standardised and identical. The clinical assessment included the Constant and Murley scores, UCLA shoulder and the Rowe score for shoulder instability. Average follow-up time was 48.3 months (SD ± 23.6 months) with a mean age of 37.1 years (SD ± 14.4 years). The work load was classified according to the German REFA Association. Operation time, duration of inability for work and clinical outcome were analysed and compared according to the operation technique. RESULTS: Mean incapacity for work in the group of arthroscopic BR was 3.3 months (SD ± 2.5) and 2.7 months (SD + 2.3 months; p = 0.37) in the group of open BR demonstrating no statistical difference. Both mean time for surgery (p = 0.0003) and in-hospital stay (p = 0.0083) showed significant differences when comparing patients with low work load (REFA 0-1) and higher work load (REFA 2-4) irrespective of the surgical approach. Overall analysis showed an average time of 2.3 months (SD ± 1.5) to return to work for patients with low work load (REFA 0-1) and 4.2 months (SD ± 2.9) for individuals with high work load (REFA 2-4) revealing significant differences (p = 0.0006). The mean inability for work after arthroscopic BR for patients with REFA 0-1 was 2.4 months (SD ± 1.6) and 4.2 months (± 2,9; p = 0.0053) for patients with REFA 2-4 revealing a significant difference. The mean inability for work after open BR for individuals with REFA 0-1 was 1.8 months (± 1.0) and 4.3 months (± 3.3; p = 0.1196) for individuals with REFA 2-4. Two out of 35 patients (5.7â%) with low work load (REFA 0-1) and 10 out of 37 patients (27â%) with high work load (REFA 2-4) could not return to their original occupation after arthroscopic BR. One out of 14 patients (7.1â%) with low work load (REFA 0-1) and 4 out of 7 patients (57.1â%) with high work load (REFA 2-4) could not return to their original occupation after open BR. Comparing these results between arthroscopic and open BR, no significant differences were obtained (chi-square, Pearson). Recurrent shoulder dislocation occurred in the arthroscopic group in 14.3â% (REFA 0-1) and 8.1â% (REFA 2-4) compared to the open procedure group in 0â% (REFA 0-1) and 14â% (REFA 2-4) revealing no statistically significant differences. CONCLUSION: This study showed equivalent results after performing open and arthroscopic BR with significantly shorter operation times and in-hospital stays after arthroscopic BR. Higher work loads caused longer inability for work irrespective of the chosen surgical technique. On the basis of these results we recommend arthroscopic BR as the standard primary procedure, while the overall rate of return to work without restrictions of 81.7â% has to be improved in the future.
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Artroscopía/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Reinserción al Trabajo/estadística & datos numéricos , Luxación del Hombro/cirugía , Ausencia por Enfermedad/estadística & datos numéricos , Evaluación de Capacidad de Trabajo , Carga de Trabajo/estadística & datos numéricos , Adulto , Femenino , Alemania/epidemiología , Humanos , Laparoscopía/estadística & datos numéricos , Masculino , Tempo Operativo , Estudios Retrospectivos , Factores de Riesgo , Luxación del Hombro/epidemiologíaRESUMEN
Typical Kondo insulators (KIs) can have a nontrivial Z_{2} topology because the energy gap opens at the Fermi energy (E_{F}) by a hybridization between odd- and even-parity bands. SmB_{6} deviates from such KI behavior, and it has been unclear how the insulating phase occurs. Here, we demonstrate that charge fluctuations are the origin of the topological insulating phase in SmB_{6}. Our angle-resolved photoemission spectroscopy results reveal that with decreasing temperature the bottom of the d-f hybridized band at the X[over ¯] point, which is predicted to have odd parity and is required for a topological phase, gradually shifts from below to above E_{F}. We conclude that SmB_{6} is a charge-fluctuating topological insulator.
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[1] Convective cold pools and the breakdown of nocturnal low-level jets (NLLJs) are key meteorological drivers of dust emission over summertime West Africa, the world's largest dust source. This study is the first to quantify their relative contributions and physical interrelations using objective detection algorithms and an off-line dust emission model applied to convection-permitting simulations from the Met Office Unified Model. The study period covers 25 July to 02 September 2006. All estimates may therefore vary on an interannual basis. The main conclusions are as follows: (a) approximately 40% of the dust emissions are from NLLJs, 40% from cold pools, and 20% from unidentified processes (dry convection, land-sea and mountain circulations); (b) more than half of the cold-pool emissions are linked to a newly identified mechanism where aged cold pools form a jet above the nocturnal stable layer; (c) 50% of the dust emissions occur from 1500 to 0200 LT with a minimum around sunrise and after midday, and 60% of the morning-to-noon emissions occur under clear skies, but only 10% of the afternoon-to-nighttime emissions, suggesting large biases in satellite retrievals; (d) considering precipitation and soil moisture effects, cold-pool emissions are reduced by 15%; and (e) models with parameterized convection show substantially less cold-pool emissions but have larger NLLJ contributions. The results are much more sensitive to whether convection is parameterized or explicit than to the choice of the land-surface characterization, which generally is a large source of uncertainty. This study demonstrates the need of realistically representing moist convection and stable nighttime conditions for dust modeling. Citation: Heinold, B., P. Knippertz, J. H. Marsham, S. Fiedler, N. S. Dixon, K. Schepanski, B. Laurent, and I. Tegen (2013), The role of deep convection and nocturnal low-level jets for dust emission in summertime West Africa: Estimates from convection-permitting simulations, J. Geophys. Res. Atmos., 118, 4385-4400, doi:10.1002/jgrd.50402.
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[1] This study presents the first climatology for the dust emission amount associated with Nocturnal Low-Level Jets (NLLJs) in North Africa. These wind speed maxima near the top of the nocturnal boundary layer can generate near-surface peak winds due to shear-driven turbulence in the course of the night and the NLLJ breakdown during the following morning. The associated increase in the near-surface wind speed is a driver for mineral dust emission. A new detection algorithm for NLLJs is presented and used for a statistical assessment of NLLJs in 32 years of ERA-Interim reanalysis from the European Centre for Medium-Range Weather Forecasts. NLLJs occur in 29% of the nights in the annual and spatial mean. The NLLJ climatology shows a distinct annual cycle with marked regional differences. Maxima of up to 80% NLLJ frequency are found where low-level baroclinicity and orographic channels cause favorable conditions, e.g., over the Bodélé Depression, Chad, for November-February and along the West Saharan and Mauritanian coast for April-September. Downward mixing of NLLJ momentum to the surface causes 15% of mineral dust emission in the annual and spatial mean and can be associated with up to 60% of the total dust amount in specific areas, e.g., the Bodélé Depression and south of the Hoggar-Tibesti Channel. The sharp diurnal cycle underlines the importance of using wind speed information with high temporal resolution as driving fields for dust emission models. Citation: Fiedler, S., K. Schepanski, B. Heinold, P. Knippertz, and I. Tegen (2013), Climatology of nocturnal low-level jets over North Africa and implications for modeling mineral dust emission, J. Geophys. Res. Atmos., 118, 6100-6121, doi:10.1002/jgrd.50394.
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Graveyards have been a matter of controversial debate for many years in terms of the risk they pose to the environment. However, literature data are inconclusive and there are no systematic studies available from modern graveyards with special reference to soil found in the vicinity of the coffin. To our knowledge, the present study is the first to systematically investigate a comprehensive exhumation series (involving 40 graves) in order to determine burial-related changes in matter and element content. Human burials lead to the accumulation of certain elements, with higher than normal levels of N, C, Zn, Ba, Ca and Na being observed in soils below coffins. Decomposition material inside coffins has much higher levels of heavy metals and alkaline elements than the surrounding soil. However, the major problem observed was the large quantity of synthetic bedding material which is more likely to lead to the formation of adipocere under the moist conditions given. Adipocere formation, which is the result of the anaerobic bacterial hydrolysis of fat, is known to interrupt the natural decomposition process and delay the post-mortem release of elements. We assume that once the inhumed matter has completely decomposed, much higher than normal levels of pollutants will be released into and have an ecological effect on the soil and water environment.
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Huesos/química , Entierro , Cambios Post Mortem , Contaminantes del Suelo/análisis , Suelo/análisis , Alemania , Humanos , Espectrometría de Masas , Metales Pesados/análisisRESUMEN
There is increasing demand for automated cell reprogramming in the fields of cell biology, biotechnology and the biomedical sciences. Microfluidic-based platforms that provide unattended manipulation of adherent cells promise to be an appropriate basis for cell manipulation. In this study we developed a magnetically driven cell carrier to serve as a vehicle within an in vitro environment. To elucidate the impact of the carrier on cells, biocompatibility was estimated using the human adenocarcinoma cell line Caco-2. Besides evaluation of the quality of the magnetic carriers by field emission scanning electron microscopy, the rate of adherence, proliferation and differentiation of Caco-2 cells grown on the carriers was quantified. Moreover, the morphology of the cells was monitored by immunofluorescent staining. Early generations of the cell carrier suffered from release of cytotoxic nickel from the magnetic cushion. Biocompatibility was achieved by complete encapsulation of the nickel bulk within galvanic gold. The insulation process had to be developed stepwise and was controlled by parallel monitoring of the cell viability. The final carrier generation proved to be a proper support for cell manipulation, allowing proliferation of Caco-2 cells equal to that on glass or polystyrene as a reference for up to 10 days. Functional differentiation was enhanced by more than 30% compared with the reference. A flat, ferromagnetic and fully biocompatible carrier for cell manipulation was developed for application in microfluidic systems. Beyond that, this study offers advice for the development of magnetic cell carriers and the estimation of their biocompatibility.
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Oro/química , Magnetismo , Imanes , Ensayo de Materiales , Técnicas Analíticas Microfluídicas , Níquel/química , Células CACO-2 , Adhesión Celular , Proliferación Celular , HumanosRESUMEN
Fourteen cases with constitutional small supernumerary marker chromosomes (sSMCs) were assessed by combination of diverse techniques including genome-wide high-resolution chromosomal microarray (CMA), chromosome banding analysis (G banding), fluorescence in situ hybridization (FISH), and quantitative real-time PCR (qPCR). Of the 14 sSMCs, 4 were complex sSMCs composed of genomic materials from more than one chromosome, 7 were simple sSMCs which contain only centromeric and/or pericentromeric regions from individual chromosomes, and the remaining 3 sSMCs contained inverted duplications. CMA precisely defined the breakpoints and genetic contents in 12 of the 14 sSMCs but failed to identify 2 of the 14 sSMCs due to lack of detectable euchromatin. In addition, CMA revealed unexpected genomic abnormalities in 2 cases. FISH techniques were necessary for the determination of the physical location, structure, formation mechanism, mosaic level, and origin of all these sSMCs. Our data emphasize the necessity to combine these methods for comprehensive characterization of sSMCs.
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Aberraciones Cromosómicas , Bandeo Cromosómico/métodos , Hibridación Fluorescente in Situ/métodos , Análisis por Micromatrices/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Niño , Eucromatina/genética , HumanosRESUMEN
The aims of this study were to create a copy number variant (CNV) profile of human chromosome 22 and to establish a genotype-phenotype correlation for patients with genomic abnormalities on chromosome 22. Thus, 1,654 consecutive pediatric patients with a diversity of clinical findings were evaluated by high-resolution chromosomal microarray analysis (CMA). We identified 25 individuals with abnormal CNVs on chromosome 22, representing 1.5% of the cases analyzed in this cohort. Meanwhile, we detected 1,298 benign CNVs on this chromosome in these individuals. Twenty-one of the 25 abnormal CNVs and the majority of the benign CNVs occurred through involvement of the 8 unstable genomic regions enriched with low copy repeats (LCR22A-H). The highly dynamic status of LCR22s within the 22q11 region facilitates the formation of diverse genomic abnormalities. This CNV profile provides a general perspective of the spectrum of chromosome 22 genomic imbalances and subsequently improves the CNV-phenotype correlations.
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Aberraciones Cromosómicas , Trastornos de los Cromosomas/genética , Cromosomas Humanos Par 22/genética , Dosificación de Gen , Niño , Bandeo Cromosómico , Trastornos de los Cromosomas/patología , Estudios de Cohortes , Femenino , Eliminación de Gen , Duplicación de Gen , Estudios de Asociación Genética , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Reacción en Cadena de la PolimerasaRESUMEN
Wetlands contribute considerably to the global greenhouse gas (GHG) balance. In these ecosystems, groundwater level (GWL) and temperature, two factors likely to be altered by climate change, exert important control over CO(2), CH(4) and N(2)O fluxes. However, little is known about the temperature sensitivity (Q(10)) of the combined GHG emissions from hydromorphic soils and how this Q(10) varies with GWL. We performed a greenhouse experiment in which three different (plant-free) hydromorphic soils from a temperate spruce forest were exposed to two GWLs (an intermediate GWL of -20 cm and a high GWL of -5 cm). Net CO(2), CH(4) and N(2)O fluxes were measured continuously. Here, we discuss how these fluxes responded to synoptic temperature fluctuations. Across all soils and GWLs, CO(2) emissions responded similarly to temperature and Q(10) was close to 2. The Q(10) of the CH(4) and N(2)O fluxes also was similar across soil types. GWL, on the other hand, significantly affected the Q(10) of both CH(4) and N(2)O emissions. The Q(10) of the net CH(4) fluxes increased from about 1 at GWL = -20 cm to 3 at GWL = -5 cm. For the N(2)O emissions, Q(10) varied around 2 for GWL = -20 cm and around 4 for GWL = -5 cm. This substantial GWL-effect on the Q(10) of CH(4) and N(2)O emissions was, however, hardly reflected in the Q(10) of the total GHG emissions (which varied around 2), because the contribution of these gases was relatively small compared to that of CO(2).
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Dióxido de Carbono/metabolismo , Efecto Invernadero , Metano/metabolismo , Óxido Nitroso/metabolismo , Microbiología del Suelo , Temperatura , Ecosistema , Gases/metabolismoRESUMEN
USAXS and SAXS patterns from cancer-bearing human breast tissue samples were recorded at beamline ID02 of the ESRF using a Bonse-Hart camera and a pinhole camera. The samples were classified as being ductal carcinoma, grade II, and ductal carcinoma in situ, partly invasive. The samples included areas of healthy collagen, invaded collagen, necrotic ducts with calcifications, and adipose tissue. The scattering patterns were analyzed in different ways to separate the scattering contribution and the direct beam from the observed rocking curve (RC) of the analyzer. It was found that USAXS from all tissues was weak, and the effects on the analyzer RC were observed only in the low-intensity tails of the patterns. The intrinsic RC was convolved with different model functions for the impulse response of the sample, and the best fit with experiment was obtained by the Pearson VII function. Significantly different distributions for the Pearson exponent m were obtained in benign and malignant regions of the samples. For a comparison with analyzer-based imaging (ABI) or diffraction enhanced imaging (DEI) a "long-slit" integration of the patterns was performed, and this emphasized the scattering contribution in the tails of the rocking curve.
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Mamografía/métodos , Refractometría/métodos , Dispersión del Ángulo Pequeño , Sincrotrones , Tomografía por Rayos X/métodos , Algoritmos , Femenino , Humanos , Imagenología Tridimensional/métodos , Técnicas In Vitro , Intensificación de Imagen Radiográfica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND AND PURPOSE: We investigated the effect of rimonabant on inflammation and enhanced platelet reactivity in type 2 diabetic Zucker rats, an experimental model of impaired glucose tolerance and the metabolic syndrome. EXPERIMENTAL APPROACH: Rimonabant (10 mg kg(-1) by gavage) was fed for 2 weeks to 3-month-old male obese Zucker rats as an impaired glucose tolerance model and for 10 weeks to 6-month-old male obese Zucker rats as a model of the metabolic syndrome. RANTES (Regulated upon Activation, Normal T cell Expressed, and Secreted) and MCP-1 (monocyte chemotactic protein-1) serum levels were determined by ELISA. Leukocyte populations were quantitatively assessed using a veterinary differential blood cell counter. Platelet activation was assessed by flow-cytometry, platelet aggregation, and adhesion of isolated platelets to immobilized fibrinogen. KEY RESULTS: RANTES and MCP-1 serum levels were increased in obese vs lean Zucker rats and significantly reduced by long-term treatment with rimonabant, which slowed weight gain in rats with the metabolic syndrome. Neutrophils and monocytes were significantly increased in young and old obese vs lean Zucker rats and lowered by rimonabant. Platelet-bound fibrinogen was significantly enhanced in obese vs lean Zucker rats of both age, and was reduced by rimonabant. Platelets from obese rats were more sensitive to thrombin-induced aggregation and adhesion to fibrinogen, which were both attenuated by rimonabant therapy. CONCLUSIONS AND IMPLICATIONS: We demonstrate positive modulation of circulating neutrophil and monocyte numbers, reduced platelet activation and lower RANTES and MCP-1 levels by rimonabant in Zucker rats. This may potentially contribute to a reduction of cardiovascular risk.
Asunto(s)
Antiinflamatorios/farmacología , Intolerancia a la Glucosa/tratamiento farmacológico , Mediadores de Inflamación/metabolismo , Leucocitos/efectos de los fármacos , Síndrome Metabólico/tratamiento farmacológico , Piperidinas/farmacología , Activación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/farmacología , Pirazoles/farmacología , Receptor Cannabinoide CB1/antagonistas & inhibidores , Animales , Quimiocina CCL2/sangre , Quimiocina CCL5/sangre , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/inmunología , Recuento de Leucocitos , Lípidos/sangre , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/inmunología , Adhesividad Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Recuento de Plaquetas , Ratas , Ratas Zucker , Rimonabant , Factores de Tiempo , Aumento de Peso/efectos de los fármacosRESUMEN
Concentrations of technical 4-nonylphenol, 4-n-octylphenol, and 4-tert-octylphenol were investigated in surface water and sediment samples of four reservoirs southwest of São Paulo. Three of them (Takimoto 1, Takimoto 2, Pedro) were established in intensively cropped landscapes, one (Morro Grande) was surrounded by dense forests. Total alkylphenol concentrations in sediments generally ranged between 1 and 10 microgkg-1dw with 4-tert-octylphenol being the dominant alkylphenol. Because 4-tert-octylphenol concentration patterns at Takimoto 2, Pedro, and in the Morro Grande forest reservoir were found to be quite similar (upto 5 microgkg-1dw), this value is considered as the ubiquitous background level. In contrast, the Takimoto 1 sediments showed significantly higher 4-tert-octylphenol concentrations, possibly due to accelerated inputs from adjacent intensively cropped fields. Analysed alkylphenols were not detectable in water samples.