39 resultados para Friedrich August I, King of Saxony, 1750-1827.
Resumo:
The long-term impact of irrigation on a Mediterranean sandy soil irrigated with Treated wastewater (TWW) since 1980 was evaluated. The main soil properties (CEC, pH, size distribution, exchangeable cations and chloride, hydraulic conductivity) as well as the organic matter and Cu, Cr and Pb speciation in an irrigated soil and a non-irrigated control soil at various soil depths were monitored and compared during a 2 years experiment. In this first part, the evolution of the physico-chemical soil properties was described. The irrigation with TWW was beneficial with regard to water and nutrient supplying. All the exchangeable cations other than K(+) were higher in the irrigated soil than in the reference one. A part of the exchangeable cations was not fixed on the exchange complex but stored as labile salts or in concentrated soil solution. Despite the very sandy soil texture, both saturated and unsaturated hydraulic conductivity exhibited a significant diminution in the irrigated soil, but remained high enough to allow water percolation during rainy periods and subsequent leaching of accumulated salts, preventing soil salinization. In the irrigated soil, exchangeable sodium percentage (ESP) exhibited high values (20% on average) and the soil organic C was lower than in the reference. No significant effect was noticed on soil mineralogical composition due to irrigation. (C) 2010 Published by Elsevier Ltd.
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The conditions for the analysis of selected doping substances by UHPSFC-MS/MS were optimized to ensure suitable peak shapes and maximized MS responses. A representative mixture of 31 acidic and basic doping agents was analyzed, in both ESI+ and ESI- modes. The best compromise for all compounds in terms of MS sensitivity and chromatographic performance was obtained when adding 2% water and 10mM ammonium formate in the CO2/MeOH mobile phase. Beside mobile phase, the nature of the make-up solvent added for interfacing UHPSFC with MS was also evaluated. Ethanol was found to be the best candidate as it was able to compensate for the negative effect of 2% water addition in ESI- mode and provided a suitable MS response for all doping agents. Sensitivity of the optimized UHPSFC-MS/MS method was finally assessed and compared to the results obtained in conventional UHPLC-MS/MS. Sensitivity was improved by 5-100-fold in UHPSFC-MS/MS vs. UHPLC-MS/MS for 56% of compounds, while only one compound (bumetanide) offered a significantly higher MS response (4-fold) under UHPLC-MS/MS conditions. In the second paper of this series, the optimal conditions for UHPSFC-MS/MS analysis will be employed to screen >100 doping agents in urine matrix and results will be compared to those obtained by conventional UHPLC-MS/MS.
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Forensic intelligence is a distinct dimension of forensic science. Forensic intelligence processes have mostly been developed to address either a specific type of trace or a specific problem. Even though these empirical developments have led to successes, they are trace-specific in nature and contribute to the generation of silos which hamper the establishment of a more general and transversal model. Forensic intelligence has shown some important perspectives but more general developments are required to address persistent challenges. This will ensure the progress of the discipline as well as its widespread implementation in the future. This paper demonstrates that the description of forensic intelligence processes, their architectures, and the methods for building them can, at a certain level, be abstracted from the type of traces considered. A comparative analysis is made between two forensic intelligence approaches developed independently in Australia and in Europe regarding the monitoring of apparently very different kind of problems: illicit drugs and false identity documents. An inductive effort is pursued to identify similarities and to outline a general model. Besides breaking barriers between apparently separate fields of study in forensic science and intelligence, this transversal model would assist in defining forensic intelligence, its role and place in policing, and in identifying its contributions and limitations. The model will facilitate the paradigm shift from the current case-by-case reactive attitude towards a proactive approach by serving as a guideline for the use of forensic case data in an intelligence-led perspective. A follow-up article will specifically address issues related to comparison processes, decision points and organisational issues regarding forensic intelligence (part II).
Resumo:
Microphthalmia with linear skin defects (MLS) syndrome is an X-linked male-lethal disorder also known as MIDAS (microphthalmia, dermal aplasia, and sclerocornea). Additional clinical features include neurological and cardiac abnormalities. MLS syndrome is genetically heterogeneous given that heterozygous mutations in HCCS or COX7B have been identified in MLS-affected females. Both genes encode proteins involved in the structure and function of complexes III and IV, which form the terminal segment of the mitochondrial respiratory chain (MRC). However, not all individuals with MLS syndrome carry a mutation in either HCCS or COX7B. The majority of MLS-affected females have severe skewing of X chromosome inactivation, suggesting that mutations in HCCS, COX7B, and other as-yet-unidentified X-linked gene(s) cause selective loss of cells in which the mutated X chromosome is active. By applying whole-exome sequencing and filtering for X-chromosomal variants, we identified a de novo nonsense mutation in NDUFB11 (Xp11.23) in one female individual and a heterozygous 1-bp deletion in a second individual, her asymptomatic mother, and an affected aborted fetus of the subject's mother. NDUFB11 encodes one of 30 poorly characterized supernumerary subunits of NADH:ubiquinone oxidoreductase, known as complex I (cI), the first and largest enzyme of the MRC. By shRNA-mediated NDUFB11 knockdown in HeLa cells, we demonstrate that NDUFB11 is essential for cI assembly and activity as well as cell growth and survival. These results demonstrate that X-linked genetic defects leading to the complete inactivation of complex I, III, or IV underlie MLS syndrome. Our data reveal an unexpected role of cI dysfunction in a developmental phenotype, further underscoring the existence of a group of mitochondrial diseases associated with neurocutaneous manifestations.
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BACKGROUND: Recombinant human insulin-like growth factor I (rhIGF-I) is a possible disease modifying therapy for amyotrophic lateral sclerosis (ALS, which is also known as motor neuron disease (MND)). OBJECTIVES: To examine the efficacy of rhIGF-I in affecting disease progression, impact on measures of functional health status, prolonging survival and delaying the use of surrogates (tracheostomy and mechanical ventilation) to sustain survival in ALS. Occurrence of adverse events was also reviewed. SEARCH METHODS: We searched the Cochrane Neuromuscular Disease Group Specialized Register (21 November 2011), CENTRAL (2011, Issue 4), MEDLINE (January 1966 to November 2011) and EMBASE (January 1980 to November 2011) and sought information from the authors of randomised clinical trials and manufacturers of rhIGF-I. SELECTION CRITERIA: We considered all randomised controlled clinical trials involving rhIGF-I treatment of adults with definite or probable ALS according to the El Escorial Criteria. The primary outcome measure was change in Appel Amyotrophic Lateral Sclerosis Rating Scale (AALSRS) total score after nine months of treatment and secondary outcome measures were change in AALSRS at 1, 2, 3, 4, 5, 6, 7, 8, 9 months, change in quality of life (Sickness Impact Profile scale), survival and adverse events. DATA COLLECTION AND ANALYSIS: Each author independently graded the risk of bias in the included studies. The lead author extracted data and the other authors checked them. We generated some missing data by making ruler measurements of data in published graphs. We collected data about adverse events from the included trials. MAIN RESULTS: We identified three randomised controlled trials (RCTs) of rhIGF-I, involving 779 participants, for inclusion in the analysis. In a European trial (183 participants) the mean difference (MD) in change in AALSRS total score after nine months was -3.30 (95% confidence interval (CI) -8.68 to 2.08). In a North American trial (266 participants), the MD after nine months was -6.00 (95% CI -10.99 to -1.01). The combined analysis from both RCTs showed a MD after nine months of -4.75 (95% CI -8.41 to -1.09), a significant difference in favour of the treated group. The secondary outcome measures showed non-significant trends favouring rhIGF-I. There was an increased risk of injection site reactions with rhIGF-I (risk ratio 1.26, 95% CI 1.04 to 1.54). . A second North American trial (330 participants) used a novel primary end point involving manual muscle strength testing. No differences were demonstrated between the treated and placebo groups in this study. All three trials were at high risk of bias. AUTHORS' CONCLUSIONS: Meta-analysis revealed a significant difference in favour of rhIGF-I treatment; however, the quality of the evidence from the two included trials was low. A third study showed no difference between treatment and placebo. There is no evidence for increase in survival with IGF1. All three included trials were at high risk of bias.
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Vitellogenin genes are expressed specifically in the liver of female oviparous vertebrates under the strict control of estrogen. To explain this tissue-specific expression, we performed a detailed analysis of the Xenopus laevis vitellogenin gene B1 promoter by DNase I footprinting and gel mobility-shift assays. We characterized five binding sites for the ubiquitous factor CTF/NF-I. Two of these sites are close to the TATA-box, whereas the others are located on both sides of the estrogen responsive unit formed by two imperfect estrogen response elements. Moreover two liver-enriched factors, C/EBP and HNF3, were found to interact with multiple closely spaced proximal promoter elements in the first 100 base pairs upstream of the TATA-box. To confirm the physiological significance of this in vitro analysis, in vivo DNase I footprinting experiments were carried out using the ligation-mediated polymerase chain reaction technique. The various cis-elements characterized in vitro as binding sites for known transcription factors and more particularly for liver-enriched transcription factors are efficiently recognized in vivo as well, suggesting that they play an important role in the control of the liver-specific vitellogenin gene B1 expression.
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We used stepwise photochemical cross-linking for specifically assembling soluble and covalent complexes made of a T-cell antigen receptor (TCR) and a class I molecule of the major histocompatibility complex (MHC) bound to an antigenic peptide. For that purpose, we have produced in myeloma cells a single-chain Fv construct of a TCR specific for a photoreactive H-2Kd-peptide complex. Photochemical cross-linking of this TCR single-chain Fv with a soluble form of the photoreactive H-2Kd-peptide ligand resulted in the formation of a ternary covalent complex. We have characterized the soluble ternary complex and showed that it reacted with antibodies specific for epitopes located either on the native TCR or on the Kd molecules. By preventing the fast dissociation kinetics observed with most T cell receptors, this approach provides a means of preparing soluble TCR-peptide-MHC complexes on large-scale levels.
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The treatment of patients with recurrent glioblastoma remains a major oncologic problem, with median survival after progression of 7-9 months. To determine the maximum tolerated dose and dose-limiting toxicity (DLT), the combination of dasatinib and cyclonexyl-chloroethyl-nitrosourea (CCNU) was investigated in this setting. The study was designed as multicenter, randomized phase II trial, preceded by a lead-in safety phase. The safety component reported here, which also investigated pharmacokinetics and preliminary clinical activity, required expansion and is therefore considered a phase I part to establish a recommended dosing regimen of the combination of CCNU (90-110 mg/m(2)) and dasatinib (100-200 mg daily). Overall, 28 patients were screened, and 26 patients were enrolled. Five dose levels were explored. DLTs, mainly myelosuppression, occurred in 10 patients. Grade 3 or 4 neutropenia was recorded in 7 patients (26.9%) and thrombocytopenia in 11 patients (42.3%). No significant effect of CCNU coadministration on dasatinib pharmacokinetics was found. Median progression-free survival (PFS) was 1.35 months (95% confidence interval: 1.2-1.4) and 6-month PFS was 7.7%. In this phase I study of recurrent glioblastoma patients, the combination of CCNU and dasatinib showed significant hematological toxicities and led to suboptimal exposure to both agents.
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The Ly49A NK cell receptor interacts with MHC class I (MHC-I) molecules on target cells and negatively regulates NK cell-mediated target cell lysis. We have recently shown that the MHC-I ligand-binding capacity of the Ly49A NK cell receptor is controlled by the NK cells' own MHC-I. To see whether this property was unique to Ly49A, we have investigated the binding of soluble MHC-I multimers to the Ly49 family receptors expressed in MHC-I-deficient and -sufficient C57BL/6 mice. In this study, we confirm the binding of classical MHC-I to the inhibitory Ly49A, C and I receptors, and demonstrate that detectable MHC-I binding to MHC-I-deficient NK cells is exclusively mediated by these three receptors. We did not detect significant multimer binding to stably transfected or NK cell-expressed Ly49D, E, F, G, and H receptors. Yet, we identified the more distantly related Ly49B and Ly49Q, which are not expressed by NK cells, as two novel MHC-I receptors in mice. Furthermore, we show using MHC-I-sufficient mice that the NK cells' own MHC-I significantly masks the Ly49A and Ly49C, but not the Ly49I receptor. Nevertheless, Ly49I was partly masked on transfected tumor cells, suggesting that the structure of Ly49I is compatible in principal with cis binding of MHC-I. Finally, masking of Ly49Q by cis MHC-I was minor, whereas masking of Ly49B was not detected. These data significantly extend the MHC-I specificity of Ly49 family receptors and show that the accessibility of most, but not all, MHC-I-binding Ly49 receptors is modulated by the expression of MHC-I in cis.
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This article describes the application of a recently developed general unknown screening (GUS) strategy based on LC coupled to a hybrid linear IT-triple quadrupole mass spectrometer (LC-MS/MS-LIT) for the simultaneous detection and identification of drug metabolites following in vitro incubation with human liver microsomes. The histamine H1 receptor antagonist loratadine was chosen as a model compound to demonstrate the interest of such approach, because of its previously described complex and extensive metabolism. Detection and mass spectral characterization were based on data-dependent acquisition, switching between a survey scan acquired in the ion-trapping Q3 scan mode with dynamic subtraction of background noise, and a dependent scan in the ion-trapping product ion scan mode of automatically selected parent ions. In addition, the MS(3) mode was used in a second step to confirm the structure of a few fragment ions. The sensitivity of the ion-trapping modes combined with the selectivity of the triple quadrupole modes allowed, with only one injection, the detection and identification of 17 phase I metabolites of loratadine. The GUS procedure used in this study may be applicable as a generic technique for the characterization of drug metabolites after in vitro incubation, as well as probably in vivo experiments.
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The epithelial sodium channel (ENaC) is preferentially assembled into heteromeric alphabetagamma complexes. The alpha and gamma (not beta) subunits undergo proteolytic cleavage by endogenous furin-like activity correlating with increased ENaC function. We identified full-length subunits and their fragments at the cell surface, as well as in the intracellular pool, for all homo- and heteromeric combinations (alpha, beta, gamma, alphabeta, alphagamma, betagamma, and alphabetagamma). We assayed corresponding channel function as amiloride-sensitive sodium transport (I(Na)). We varied furin-mediated proteolysis by mutating the P1 site in alpha and/or gamma subunit furin consensus cleavage sites (alpha(mut) and gamma(mut)). Our findings were as follows. (i) The beta subunit alone is not transported to the cell surface nor cleaved upon assembly with the alpha and/or gamma subunits. (ii) The alpha subunit alone (or in combination with beta and/or gamma) is efficiently transported to the cell surface; a surface-expressed 65-kDa alpha ENaC fragment is undetected in alpha(mut)betagamma, and I(Na) is decreased by 60%. (iii) The gamma subunit alone does not appear at the cell surface; gamma co-expressed with alpha reaches the surface but is not detectably cleaved; and gamma in alphabetagamma complexes appears mainly as a 76-kDa species in the surface pool. Although basal I(Na) of alphabetagamma(mut) was similar to alphabetagamma, gamma(mut) was not detectably cleaved at the cell surface. Thus, furin-mediated cleavage is not essential for participation of alpha and gamma in alphabetagamma heteromers. Basal I(Na) is reduced by preventing furin-mediated cleavage of the alpha, but not gamma, subunits. Residual current in the absence of furin-mediated proteolysis may be due to non-furin endogenous proteases.
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Chronic blockade of the renin angiotensin system became possible when orally active inhibitors of angiotensin converting enzyme, the enzyme which catalyzes the transformation of angiotensin I into angiotensin II, were synthetized. Two compounds, captopril and enalapril, have been investigated in clinical studies. The decrease of the pressor response to exogenous angiotensin I and of the circulating levels of angiotensin II following administration of these inhibitors has been demonstrated to be directly related to the degree of suppression of plasma angiotensin converting enzyme activity. These inhibitors have been shown to normalize blood pressure alone in some hypertensive patients whereas in many others, satisfactory blood pressure control can be achieved only after the addition of a diuretic. Captopril and enalapril also markedly improve cardiac function of patients with chronic congestive heart failure. Chronic blockade of the renin angiotensin system has therefore provided an interesting new approach to the treatment of clinical hypertension and heart failure.
Resumo:
Acid mine drainage (AMD) from the Zn-Pb(-Ag-Bi-Cu) deposit of Cerro de Pasco (Central Peru) and waste water from a Cu-extraction plant has been discharged since 1981 into Lake Yanamate, a natural lake with carbonate bedrock. The lake has developed a highly acidic pH of similar to 1. Mean lake water chemistry was characterized by 16,775 mg/L acidity as CaCO(3), 4330 mg/L Fe and 29,250 mg/L SO(4). Mean trace element concentrations were 86.8 mg/L Cu, 493 mg/L Zn, 2.9 mg/L Pb and 48 mg/L As, which did not differ greatly from the discharged AMD. Most elements showed increasing concentrations from the surface to the lake bottom at a maximal depth of 41 m (e.g. from 3581 to 5433 mg/L Fe and 25,609 to 35,959 mg/L SO(4)). The variations in the H and 0 isotope compositions and the element concentrations within the upper 10 m of the water column suggest mixing with recently discharged AMD, shallow groundwater and precipitation waters. Below 15 m a stagnant zone had developed. Gypsum (saturation index, SI similar to 0.25) and anglesite (SI similar to 0.1) were in equilibrium with lake water. Jarosite was oversaturated (SI similar to 1.7) in the upper part of the water column, resulting in downward settling and re-dissolution in the lower part of the water column (SI similar to -0.7). Accordingly, jarosite was only found in sediments from less than 7 m water depth. At the lake bottom, a layer of gel-like material (similar to 90 wt.% water) of pH similar to 1 with a total organic C content of up to 4.40 wet wt.% originated from the kerosene discharge of the Cu-extraction plant and had contaminant element concentrations similar to the lake water. Below the organic layer followed a layer of gypsum with pH 1.5, which overlaid the dissolving carbonate sediments of pH 5.3-7. In these two layers the contaminant elements were enriched compared to lake water in the sequence As < Pb approximate to Cu < Cd < Zn = Mn with increasing depth. This sequence of enrichment was explained by the following processes: (i) adsorption of As on Fe-hydroxides coating plant roots at low pH (up to 3326 mg/kg As), (ii) adsorption at increasing pH near the gypsum/calcite boundary (up to 1812 mg/kg Pb, 2531 mg/kg Cu. and 36 mg/kg Cd), and (iii) precipitation of carbonates (up to 5177 mg/kg Zn and 810 mg/kg Mn: all data corrected to a wet base). The infiltration rate was approximately equal to the discharge rate, thus gypsum and hydroxide precipitation had not resulted in complete clogging of the lake bedrocks. (C) 2010 Elsevier Ltd. All rights reserved.