968 resultados para Cu(In,Ga)Se2 (CIGS)


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Recovery of group B streptococci (GBS) was assessed in 1,204 vaginorectal swabs stored in Amies transport medium at 4 or 21°C for 1 to 4 days either by direct inoculation onto Granada agar (GA) or by culture in blood agar (BA) and GA after a selective broth enrichment (SBE) step. Following storage at 4°C, GBS detection in GA was not affected after 72 h by either direct inoculation or SBE; however, GBS were not detected after SBE in the BA subculture in some samples after 48 h of storage and in GA after 96 h. After storage at 21°C, loss of GBS-positive results was significant after 48 h by direct inoculation in GA and after 96 h by SBE and BA subculture; some GBS-positive samples were not detected after 24 h of storage followed by SBE and BA subculture or after 48 h of storage followed by SBE and GA subculture. Storage of swabs in transport medium, even at 4°C, produced after 24 h an underestimation of the intensity of GBS colonization in most specimens. These data indicate that viability of GBS is not fully preserved by storage of vaginorectal swabs in Amies transport medium, mainly if they are not stored under refrigeration

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Background/Purpose: The primary treatment goals for gouty arthritis (GA) are rapid relief of pain and inflammation during acute attacks, and long-term hyperuricemia management. A post-hoc analysis of 2 pivotal trials was performed to assess efficacy and safety of canakinumab (CAN), a fully human monoclonal anti-IL-1_ antibody, vs triamcinolone acetonide (TA) in GA patients unable to use NSAIDs and colchicine, and who were on stable urate lowering therapy (ULT) or unable to use ULT. Methods: In these 12-week, randomized, multicenter, double-blind, double-dummy, active-controlled studies (_-RELIEVED and _-RELIEVED II), patients had to have frequent attacks (_3 attacks in previous year) meeting preliminary GA ACR 1977 criteria, and were unresponsive, intolerant, or contraindicated to NSAIDs and/or colchicine, and if on ULT, ULT was stable. Patients were randomized during an acute attack to single dose CAN 150 mg s.c. or TA 40 mg i.m. and were redosed "on demand" for each new attack. Patients completing the core studies were enrolled into blinded 12-week extension studies to further investigate on-demand use of CAN vs TA for new attacks. The subpopulation selected for this post-hoc analysis was (a) unable to use NSAIDs and colchicine due to contraindication, intolerance or lack of efficacy for these drugs, and (b) currently on ULT, or contraindication or previous failure of ULT, as determined by investigators. Subpopulation comprised 101 patients (51 CAN; 50 TA) out of 454 total. Results: Several co-morbidities, including hypertension (56%), obesity (56%), diabetes (18%), and ischemic heart disease (13%) were reported in 90% of this subpopulation. Pain intensity (VAS 100 mm scale) was comparable between CAN and TA treatment groups at baseline (least-square [LS] mean 74.6 and 74.4 mm, respectively). A significantly lower pain score was reported with CAN vs TA at 72 hours post dose (1st co-primary endpoint on baseline flare; LS mean, 23.5 vs 33.6 mm; difference _10.2 mm; 95% CI, _19.9, _0.4; P_0.0208 [1-sided]). CAN significantly reduced risk for their first new attacks by 61% vs TA (HR 0.39; 95% CI, 0.17-0.91, P_0.0151 [1-sided]) for the first 12 weeks (2nd co-primary endpoint), and by 61% vs TA (HR 0.39; 95% CI, 0.19-0.79, P_0.0047 [1-sided]) over 24 weeks. Serum urate levels increased for CAN vs TA with mean change from baseline reaching a maximum of _0.7 _ 2.0 vs _0.1 _ 1.8 mg/dL at 8 weeks, and _0.3 _ 2.0 vs _0.2 _ 1.4 mg/dL at end of study (all had GA attack at baseline). Adverse Events (AEs) were reported in 33 (66%) CAN and 24 (47.1%) TA patients. Infections and infestations were the most common AEs, reported in 10 (20%) and 5 (10%) patients treated with CAN and TA respectively. Incidence of SAEs was comparable between CAN (gastritis, gastroenteritis, chronic renal failure) and TA (aortic valve incompetence, cardiomyopathy, aortic stenosis, diarrohea, nausea, vomiting, bicuspid aortic valve) groups (2 [4.0%] vs 2 [3.9%]). Conclusion: CAN provided superior pain relief and reduced risk of new attack in highly-comorbid GA patients unable to use NSAIDs and colchicine, and who were currently on stable ULT or unable to use ULT. The safety profile in this post-hoc subpopulation was consistent with the overall _-RELIEVED and _-RELIEVED II population.

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Introduction: Tyrosine kinase inhibitors (TKI) have considerably improved outcome of patients with advanced GIST and extended overall survival to more than 5 years. Yet, the median progression-free survival is approximately 2 years with first-line imatinib and 24 weeks with second-line sunitinib, which calls for treatment alternatives. Nilotinib is a second-generation TKI with at least similar inhibitory activity as imatinib. A Phase I study has shown that nilotinib monotherapy has clinical activity in GIST. Methods: After failure of all available therapeutic options patients had access to nilotinib on a compassionate use (CU) programm. Nilotinib was started at a dose of 400 mg bid, with dose reduction to 400mg qd allowed in the case of toxicity. 94 pts were approved for nilotinib CU in 10 European countries. We herein present retrospective data of 42 pts from 5 European countries treated in 11 centers. Results: Median age at nilotinib treatment start was 59 years (median; range 24-79 y). 30 of 42 patients were male. Most pts had metastatic disease of gastric origin at initial diagnosis. KIT exon 11 mutations were most frequent. The median number of surgical resections was 1 (range 0-8). All pts had failed both imatinib and sunitinib before nilotinib, and few had also received additional investigational treatments. Nilotinib was well tolerated, and discontinued due to toxicity in 15% only. Median follow-up is 176 days (range 15-876 d). Nilotinib treatment duration is 75 days (median; range 3-727 d). Partial remission with nilotinib treatment was seen in 11% of pts. Median OS was 263 days (Kaplan-Meier). Conclusion: This is the largest series reported assessing efficacy of nilotinib for imatinib- and sunitinib-refractory GIST reported yet. Nilotinib displays significant clinical activity in this heavily pretreated group of pts. These results warrant further investigation of nilotinib in GIST, including its use in first or second-line treatment. Patient and data collection is ongoing, updated results will be presented.

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P130 A HIGH-RESOLUTION 2D/3D SEISMIC STUDY OF A THRUST FAULT ZONE IN LAKE GENEVA SWITZERLAND M. SCHEIDHAUER M. BERES D. DUPUY and F. MARILLIER Institute of Geophysics University of Lausanne 1015 Lausanne, Switzerland Summary A high-resolution three-dimensional (3D) seismic reflection survey has been conducted in Lake Geneva near the city of Lausanne Switzerland where the faulted molasse basement (Tertiary sandstones) is overlain by complex Quaternary sedimentary structures. Using a single 48-channel streamer an area of 1200 m x 600 m was surveyed in 10 days. With a 5-m shot spacing and a receiver spacing of 2.5 m in the inline direction and 7.5 m in the crossline direction, a 12-fold data coverage was achieved. A maximum penetration depth of ~150 m was achieved with a 15 cu. in. water gun operated at 140 bars. The multi-channel data allow the determination of an accurate velocity field for 3D processing, and they show particularly clean images of the fault zone and the overlying sediments in horizontal and vertical sections. In order to compare different sources, inline 55 was repeated with a 30/30 and a 15/15 cu. in. double-chamber air gun (Mini GI) operated at 100 and 80 bars, respectively. A maximum penetration depth of ~450 m was achieved with this source.

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The distribution of three nuclear scaffold proteins (of which one is a component of a particular class of nuclear bodies) has been studied in intact K562 human erythroleukemia cells, isolated nuclei, and nuclear scaffolds. Nuclear scaffolds were obtained by extraction with the ionic detergent lithium diidosalicylate (LIS), using nuclei prepared in the absence of divalent cations (metal-depleted nuclei) and stabilized either by a brief heat exposure (20 min at 37C or 42C) or by Cu++ ions at 0C. Proteins were visualized by in situ immunocytochemistry and confocal microscopy. Only a 160-kD nuclear scaffold protein was unaffected by all the stabilization procedures performed on isolated nuclei. However, LIS extraction and scaffold preparation procedures markedly modified the distribution of the polypeptide seen in intact cells, unless stabilization had been performed by Cu++. In isolated nuclei, only Cu++ treatment preserved the original distribution of the two other antigens (M(r), 125 and 126 kD), whereas in heat-stabilized nuclei we detected dramatic changes. In nuclear scaffolds reacted with antibodies to 125 and 126-kD proteins, the fluorescent pattern was always disarranged regardless of the stabilization procedure. These results, obtained with nuclei prepared in the absence of Mg+2 ions, indicate that heat treatment per se can induce changes in the distribution of nuclear proteins, at variance with previous suggestions. Nevertheless, each of the proteins we have studied behaves in a different way, possibly because of its specific association with the nuclear scaffold.

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Systematic pig slurry application to crop soils may lead to the accumulation of heavy metals in regions with intensive pig raising. The aim of this study was to evaluate the accumulation of Cu, Zn and Mn in soils under systematic pig slurry application. For this purpose, soil samples were collected from two of the most representative watersheds of Santa Catarina where the predominant activity is pig raising. In each watershed, 12 properties were chosen to evaluate the different systems of pig husbandry (complete cycle (CC), farrowing (FaU) and finishing units (FiU)). Based on information of the producers, soil samples were collected in areas with and without systematic manure application. To determine the total Cu, Zn and Mn content in soils and manure, a methodology proposed by the Environmental Protection Agency of the United States (USEPA), method nº 3050B, was used. For the available heavy metal content, Cu and Zn was extracted with HCl 0.1 mol L-1 and Mn with KCl 1 mol L-1. Data were subjected to multivariate analysis, using the canonical discriminant analysis to identify the metals that best differentiate the soils studied within each swine housing system. Successive pig slurry applications cause an increase in Cu, Zn and Mn availability in the soil and this indicates the need for monitoring of the metal concentrations over time. The critical values of Cu in the soil can be reached and exceeded more rapidly than Zn. The results showed that the soil type may be one of the attribute underlying the determination of public policies in pig raising and waste management because soils such as Inceptisols were shown to be more prone to possible contamination since they may more rapidly reach total critical Cu levels.

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The expansion of Brazilian agriculture has led to a heavy dependence on imported fertilizers to ensure the supply of the growing food demand. This fact has contributed to a growing interest in alternative nutrient sources, such as ground silicate rocks. It is necessary, however, to know the potential of nutrient release and changes these materials can cause in soils. The purpose of this study was to characterize six silicate rocks and evaluate their effects on the chemical properties of treated soil, assessed by chemical extractants after greenhouse incubation. The experimental design consisted of completely randomized plots, in a 3 x 6 factorial scheme, with four replications. The factors were potassium levels (0-control: without silicate rock application; 200; 400; 600 kg ha-1 of K2O), supplied as six silicate rock types (breccia, biotite schist, ultramafic rock, phlogopite schist and two types of mining waste). The chemical, physical and mineralogical properties of the alternative rock fertilizers were characterized. Treatments were applied to a dystrophic Red-Yellow Oxisol (Ferralsol), which was incubated for 100 days, at 70 % (w/w) moisture in 3.7 kg/pots. The soil was evaluated for pH; calcium and magnesium were extracted with KCl 1 mol L-1; potassium, phosphorus and sodium by Mehlich 1; nickel, copper and zinc with DTPA; and the saturation of the cation exchange capacity was calculated for aluminum, calcium, magnesium, potassium, and sodium, and overall base saturation. The alternative fertilizers affected soil chemical properties. Ultramafic rock and Chapada mining byproduct (CMB) were the silicate rocks that most influenced soil pH, while the mining byproduct (MB) led to high K levels. Zinc availability was highest in the treatments with mining byproduct and Cu in soil fertilized with Chapada and mining byproduct.

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ABSTRACT Heavy metals contained in electronic waste, if discarded improperly, can become bioavailable after vermicomposting, posing a risk to the environment. Small-scale vermicomposting experiments were carried out with printed circuit boards (PCBs) to investigate the migration of heavy metals (Cu, Pb, Zn, Ni, and Sn) to the final compost, as well as the mobility and bioavailability of these metals. High total levels of Pb, Sn and Cu in samples of manure with electronic waste (MEW) and vegetables with electronic waste (VEW) were detected. Based on the initial metal levels in the PCBs and their concentration in the resulting compost, the order of migration of these metals to the MEW and VEW samples was Sn (23.1 %)>Pb (18.4 %)>Ni (4.63 %)>Zn (0.46 %)>Cu (0.14 %) and Sn (24.3 %)>Pb (23.6 %)>Ni (11.33 %)>Zn (1.76 %)>Cu (0.60 %), respectively. Mobility and bioavailability of these metals in the compost were evaluated by three-stage sequential extraction, where F1 was the exchangeable fraction, F2 the organic fraction and F3 the residual fraction. The bioavailability factor (BF) was calculated by the ratio of the sum of fractions F1 and F2 divided by the total sum of the fractions (F1 + F2 + F3). The highest bioavailability factor (BF = 0.92) was found for Pb, the heavy metal considered the greatest environmental concern in this study, indicating the high mobility and the possibility of becoming bioavailable of this metal.

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BACKGROUND: Previous studies on the impact of cannabis use disorders (CU) on outcome in psychosis were predominantly based on non representative samples, often have not controlled for confounders and rarely focused on adolescent patients. Thus, the aims of the present study were to assess: (i) prevalence of CU; (ii) baseline and pretreatment differences between CU and those without CU (NCU); (iii) the impact of baseline and course of CU on 18-month outcomes in a representative cohort of adolescents with early onset first episode psychosis (EOP). METHODS: The sample comprised 99 adolescents (age 14 to 18) with EOP (onset age 14 to 17), admitted to the Early Psychosis Prevention and Intervention Centre in Australia. Data were collected from medical files using a standardized questionnaire. RESULTS: Prevalence of lifetime CU was 65.7%, of current CU at baseline 53.5%, and of persistent CU throughout treatment 26.3%. Baseline CU compared to NCU had significantly higher illness-severity, lower psychosocial functioning, less insight, lower premorbid functioning and longer duration of untreated psychosis. Compared to all other groups, only persistent CU was linked to worse outcomes and more service disengagement. Effect sizes were medium controlling for relevant confounders. Medication non-adherence did not explain the association between persistent CU and worse outcome. CONCLUSIONS: Baseline CU was associated with worse baseline characteristics, but only persistent CU was linked with worse outcome. About half of those with baseline CU reduced cannabis during treatment. For these, effectively treating the psychotic disorder may already be beneficial. However, future research is necessary on the reasons for persistent CU in EOP and its treatment.

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The objective of this work was to determine the influence of Zn, Mn and Cu on shoot dry matter yield and uptake of macro and micronutrients in upland rice, common bean and corn. Six greenhouse experiments were conducted using a Dark Red Latosol (Typic Haplusthox). Treatments consisted of application of Zn at 0, 5, 10, 20, 40, 80 and 120 mg kg-1, of Mn at 0, 10, 20, 40, 80, 160, 320 and 640 mg kg-1 and of Cu application at 0, 2, 4, 8, 32, 64 and 96 mg kg-1. Zinc increased yield of rice, Mn increased yields of corn and bean and Cu improved yields of rice and bean. Uptake of N, Ca, and Cu in rice was decreased by zinc treatment. In common bean, uptake of N, Mg, and Cu was increased by zinc application, whereas, uptake of P was decreased. Manganese increased uptake of Mg, Zn and Fe and decreased uptake of Ca, in corn. Uptake of K, Zn and Mn was increased and uptake of P and Cu was decreased by Mn application, in bean. Copper had positive and negative interactions in the uptake of macro and micronutrients, depending on crop species and nutrients involved.

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The breccia-hosted epithermal Au-Ag deposit of Rosia Montana is located 7 kin northeast of Abrud, in the northern part of the South Apuseni Mountains, Romania. Estimated total reserves of 214.91 million metric toils (Mt) of ore at 1.46 g/t An and 6.9 g/t Ag (10.1 Moz of An and 47.6 Moz of Ag) make Rosia Montana one of the largest gold deposits in Europe. At this location, Miocene calc-alkaline magmatic and hydrothermal activity was associated with local extensional tectonics within a strike-slip regime related to the indentation of the Adriatic microplate into the European plate during the Carpathian orogenesis. The host rocks of the magmatic complex consist of pre-Mesozoic metamorphosed continental crust covered by Cretaceous turbiditic sediment (flysch). Magmatic activity at Rosia Montana and its surroundings occurred in several pulses and lasted about 7 m.y, Rosia Montana is a breccia-hosted epithermal system related to strong phreatomagmatic activity due to the shallow emplacement of the Montana dacite. The Montana dacite intruded Miocene volcaniclastic material (volcaniclastic breccias) and crops out at Cetate and Carnic Hills. Current mining is focused primarily on the Cetate open pit, which was mapped in detail, leading to the recognition of three distinct breccia bodies: the dacite breccia with a dominantly hydrothermal matrix, the gray polymict breccia with a greater proportion of sand-sized matrix support, and the black polymict breccia, which reached to the surface, contains carbonized tree trunks and has a dominantly barren elastic matrix. The hydrothermal alteration is pervasive. Adularia alteration with a phyllic overprint is ubiquitous; silicification and argillic alteration occur locally. Mineralization consists of quartz, adularia, carbonates (commonly Mn-rich), pyrite, Fe-poor sphalerite, galena, chalcopyrite, tetrahedrite, and native gold and occurs as disseminations, as well as in veins and filling vugs within the Montana dacite and the different breccias. The age of mineralization (12.85 +/- 0.07 Ma) was determined by Ar-40- Ar-39 dating on hydrothermal adularia crystals from vugs in the dacite breccia in the Cetate open pit. Microthermometric measurements of fluid inclusions in quartz phenocrysts from the Montana dacite revealed two fluid types that are absent from the hydrothermal breccia and must have been trapped at depth prior to dacite dome emplacement: brine inclusions (32-55 -wt % NaCl equiv, homogenizing at T-h > 460 degrees C) and intermediate density fluids (4.9-15.6 wt % NaCl equiv, T, between 345 degrees-430 degrees C). Secondary aqueous fluid inclusion assemblages in the phenocrysts have salinities of 0.2 to 2.2 wt percent NaCl equiv and T-h of 200 degrees to 280 degrees C. Fluid inclusion assemblages in hydrothermal quartz from breccias and veins have salinities of 0.2 to 3.4 wt percent NaCl equiv and T-h, from 200 degrees to 270 degrees C. The oxygen isotope composition of several zones of an ore-related epithermal quartz crystal indicate a very constant delta O-18 of 4.5 to 5.0 per mil for the mineralizing fluid, despite significant salinity and temperature variation over time. Following microthermometry, selected fluid inclusion assemblages were analyzed by laser ablation-inductively coupled-plasma mass spectrometry (LA-ICMS). Despite systematic differences in salinity between phenocryst-hosted fluids trapped at depth and fluids from quartz in the epithermal breccias, all fluids have overlapping major and trace cation ratios, including identical Na/K/Rb/Sr/Cs/Ba. Consistent with the constant near-magmatic oxygen isotope composition of the hydrothermal fluids, these data strongly indicate a common magmatic component of these chemically conservative solutes in all fluids. Cu, Pb, Zn, and Mn show variations in concentration relative to the relatively non-reactive alkalis, reflecting the precipitation of sulfide minerals together with An in the epithermal breccia, and possibly of Cu in an inferred subjacent porphyry environment. The magmatic-hydrothermal processes responsible for epithermal Au-Ag mineralization at Rosia Montana are, however, not directly related to the formation of the spatially associated porphyry Cu-Au deposit of Rosia Poieni, which occurred lout 3 m.y. later.

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Glutaric aciduria type-I (GA-I) and methylmalonic aciduria (MMA-uria) are two neurometabolic diseases manifesting in neonatal period and early childhood. They belong to the group of organic acidurias and are caused by defects in the catabolism of amino acids, leading to massive accumulation of toxic metabolites in the body and severe brain injury. Therapeutic strategies are mainly based on reversing catabolic state during metabolic crisis and dietary protein restriction that both aim to prevent extra production of toxic metabolites. Specific and neuroprotective treatments are missing because the mechanisms of brain damage in these diseases are only poorly understood. The principal objective of my work was to develop in vitro models for both diseases aiming at elucidation of toxic effects of the main metabolites accumulating in GA-I (glutaric acid (GA) and 3-hydroxy glutaric acid (3-OHGA)) and MMA-uria (methylmalonic acid (MMA), propionic acid (PA) and 2-methylcitric acid (2-MCA)) on developing brain cells, and to study the cellular pathways targeted by these deleterious effects in order to find new therapeutic potentials. We used re-aggregated embryonic rat brain cells in organotypic 3D cultures, which were exposed to toxic metabolites at different developing stages of the cultures. In parallel, we studied the cellular localization of the defected enzyme in GA-I, glutaryl-CoA dehydrogenase (GCDH), in the brain and peripheral tissues of rats in adulthood and during embryonic development. GCDH expression: GCDH showed a strong neuronal expression in embryonic central and peripheral nervous system. In the adult brain, GCDH expression was exclusively neuronal with the strongest signal in cerebral cortex and Purkinje cells. GCDH expression was homogenous in embryonic peripheral organs with high levels in intestinal mucosa at late stages. Strong GCDH expression was also observed in liver and intestinal mucosa and with lower intensity in muscles, convoluted renal tubules and renal collecting tubes in adult peripheral organs. GA-I and MMA-uria in vitro models: 3-OHGA (for GA-I) and 2-MCA (for MMA-uria) showed the most deleterious effects at early stages of the cultures with morphological and biochemical alterations and induction of cell death. 3-OHGA and 2-MCA caused astrocytic cell suffering reflected by astrocytic fiber loss and swelling and retardation in oligodendrocytic maturation and/or differentiation. High ammonium increase concomitant with glutamine decrease was observed in these cultures. Neurons were not substantially affected. Our studies revealed that brain-cell generated ammonia may play a role in the neuropathogenesis of these diseases. Thus, developing neuroprotective strategies that target ammonium toxicity in the brain of GA-I and MMA-uria patients might be important according to our findings. -- L'acidurie glutarique de type I (GA-I) et l'acidurie méthylmalonique (MMA-urie) sont deux maladies neurométaboliques se manifestant durant la période néonatale ou la petite enfance, et qui appartiennent aux aciduries organiques. Elles sont causées par des défauts dans le catabolisme des acides aminés, conduisant à une accumulation des métabolites toxiques dans le corps et aussi des lésions cérébrales sévères. Le traitement est limité à une prise en charge d'urgence pendant la crise métabolique et à une diète restreinte en protéines naturelles. Des traitements spécifiques, neuroprotecteurs manquent principalement parce que les mécanismes conduisant aux lésions cérébrales dans ces maladies sont peu connus. L'objectif principal de mon travail était d'élucider les effets toxiques des métabolites accumulés dans GA-I (l'acide glutarique (GA) et l'acide 3-hydroxyglutarique (3-OHGA)) et MMA-uria (l'acide méthylmalonique (MMA), l'acide propionique (PA) et l'acide 2-méthylcitrique(2-MCA) sur les cellules du cerveau ainsi que les voies cellulaires impliquées, dans le but de trouver de potentielles nouvelles stratégies thérapeutiques. Nous avons utilisé un modèle in vitro de cultures 3D de cellules de cerveau d'embryons de rat (en développement) en les exposant aux métabolites toxiques à différents stades de développement des cultures. En parallèle, nous avons étudié la localisation cellulaire de l'enzyme déficiente dans GA-I, la CoA-glutarly déshydrogénase (GCDH), dans le cerveau et les organes périphériques des rats adultes et pendant le développement embryonnaire. L'expression de GCDH: GCDH a montré une expression neuronale forte dans le système nerveux chez l'embryon et le cerveau adulte. L'expression était homogène dans les organes périphériques avec une forte expression dans l'intestin. Les modèles in vitro de GA-I et MMA-uria : 3-OHGA en modèle GA-I et 2-MCA en modèle MMA-uria ont montré les effets délétères les plus importants avec des altérations morphologiques des cellules et biochimiques dans le milieu de culture et l'induction de mort cellulaire non-apoptotique (3-OHGA) ou apoptotique (2-MCA). 3-OHGA et 2-MCA ont provoqué une souffrance astrocytaire avec perte des fibres et gonflement et un retard de maturation et/ou de différentiation des oligodendrocytes. Une augmentation importante d'ammonium avec une diminution concomitante de glutamine a été observée dans les cultures. Les neurones n'étaient pas vraiment affectés. Nos études ont révélé que l'ammonium généré par les cellules cérébrales pourrait jouer un rôle dans la neuropathogenèse de ces deux maladies. Par conséquent, développer des stratégies neuroprotectrices ciblant la toxicité de l'ammonium dans le cerveau des patients atteints de GA-I ou MMA-urie pourrait être très important selon nos résultats.

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There is no evidence of urban civilization in Brazilian prehistory; most inhabitants lived in tribal groupings, probably with regional economic integration among several independent tribes. There is little evidence of seasonal migrations between the coast and the inland of southern Brazil. Some specialized horticulturists competed among themselves but other groups lived more isolated and probably peacefully, in the upper interfluvial regions. Chemical analysis of artifacts is a means of documenting traffic in particular materials and intraregional production and distribution, development of craft specialization and typological refinement among other issues. In this study we tested some possibilities in two different cultural contexts using the parametric k0 neutron activation analysis technique, which allowed the determination of elements: Al, As, Au, Ce, Cl, Co, Cr, Cs, Cu, Fe, Ga, K, La, Na, Rb, Sc, Ta, Ti, V and Zn.

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The objective of this study was to evaluate the quality and the production of biogas and biofertilizer obtained from biodigester supplied with pig feces in the initial, growing and finishing stages, fed with diets formulated based on corn or sorghum. Twenty bench biodigesters were used with hydraulic retention time of 30 days and daily loads that contained 4 to 6% of total solids (TS) and 3.6 to 5.2% of volatile solids (VS). In the effluent of the biodigesters, mean levels of TS were observed ranging between 1.6 and 2.0% and of VS between 1.2 and 1.6%. The mean reductions of TS were 57.7 to 64.7% and of VS from 61.7 to 69.0%, and there was only difference in the finishing phase, in which the major averages reductions were produced by the biodigesters supplied with feces from animals fed with diets based on corn. In biodigesters supplied with feces from animals in the initial and growing stages fed with diets based on corn, were observed higher average productions of biogas and the greatest average potentials of biogas production. The average potentials obtained were 0.033; 0.181; 0.685; 0.788 and 1.132 m³ per kg of affluent, manure, TS added, VS added and VS reduced, respectively. No differences were found on the average content of methane in the biogas between diets and stages. The average concentrations of nutrients N, P, K, Ca, Mg, Na, Fe, Mn, Zn and Cu in the biodigester affluent and effluent, ranged between diets and stages.

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Initially identified as stress activated protein kinases (SAPKs), the c-Jun Nterminal kinases (JNKs) are currently accepted as potent regulators of various physiologically important cellular events. Named after their competence to phosphorylate transcription factor c-Jun in response to UVtreatment, JNKs play a key role in cell proliferation, cell death or cell migration. Interestingly, these functions are crucial for proper brain formation. The family consists of three JNK isoforms, JNK1, JNK2 and JNK3. Unlike brain specific JNK3 isoform, JNK1 and JNK2 are ubiquitously expressed. It is estimated that ten splice variants exist. However, the detailed cellular functions of these remain undetermined. In addition, physiological conditions keep the activities of JNK2 and JNK3 low in comparison with JNK1, whereas cellular stress raises the activity of these isoforms dramatically. Importantly, JNK1 activity is constitutively high in neurons, yet it does not stimulate cell death. This suggests a valuable role for JNK1 in brain development, but also as an important mediator of cell wellbeing. The aim of this thesis was to characterize the functional relationship between JNK1 and SCG10. We found that SCG10 is a bona fide target for JNK. By employing differential centrifugation we showed that SCG10 co-localized with active JNK, MKK7 and JIP1 in a fraction containing endosomes and Golgi vesicles. Investigation of JNK knockout tissues using phosphospecific antibodies recognizing JNK-specific phosphorylation sites on SCG10 (Ser 62/Ser 73) showed that phosphorylation of endogenous SCG10 was dramatically decreased in Jnk1-/- brains. Moreover, we found that JNK and SCG10 co-express during early embryonic days in brain regions that undergo extensive neuronal migration. Our study revealed that selective inhibition of JNK in the cytoplasm significantly increased both the frequency of exit from the multipolar stage and radial migration rate. However, as a consequence, it led to ill-defined cellular organization. Furthermore, we found that multipolar exit and radial migration in Jnk1 deficient mice can be connected to changes in phosphorylation state of SCG10. Also, the expression of a pseudo-phosphorylated mutant form of SCG10, mimicking the JNK1- phopshorylated form, brings migration rate back to normal in Jnk1 knockout mouse embryos. Furthermore, we investigated the role of SCG10 and JNK in regulation of Golgi apparatus (GA) biogenesis and whether pathological JNK action could be discernible by its deregulation. We found that SCG10 maintains GA integrity as with the absence of SCG10 neurons present more compact fragmented GA structure, as shown by the knockdown approach. Interestingly, neurons isolated from Jnk1-/- mice show similar characteristics. Block of ER to GA is believed to be involved in development of Parkinson's disease. Hence, by using a pharmacological approach (Brefeldin A treatment), we showed that GA recovery is delayed upon removal of the drug in Jnk1-/- neurons to an extent similar to the shRNA SCG10-treated cells. Finally, we investigated the role of the JNK1-SCG10 duo in the maintenance of GA biogenesis following excitotoxic insult. Although the GA underwent fragmentation in response to NMDA treatment, we observed a substantial delay in GA disintegration in neurons lacking either JNK1 or SCG10.