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731.
Karina S. Matos Elaine F.F. da Cunha Arlan da Silva Gonçalves Alan Wilter Kamil Kuča Tanos C.C. França 《Journal of biomolecular structure & dynamics》2013,31(5):546-558
We have applied a theoretical methodology, previously developed to evaluate the association and kinetic reactivation constants of oximes, comparing theoretical data obtained for human acetylcholinesterase (HsAChE) with in vitro results from Mus musculus AChE (MmAChE) previously reported in the literature. Our results, further checked by additional molecular dynamics simulations steps, showed a good correlation between the theoretical and experimental data, supporting the methodology as appropriate for prediction of thermodynamic and kinetic parameters and corroborated MmAChE as a suitable model for studies with HsAChE. 相似文献
732.
Ana Sofia Fonseca Maria Isabel Nunes Manuel Arlindo Matos Ana Paula Gomes 《The International Journal of Life Cycle Assessment》2013,18(7):1374-1385
Purpose
In Portugal, the management of end-of-life vehicles (ELV) is set out in targets of the European Union policy for the year 2015, including 85 % recycling, 95 % recovery, and maximum of 5 % landfilling. These goals will be attained only through more efficient technologies for waste separation and recycling of shredder residues or higher rates of dismantling components. Focusing on this last alternative, a field experiment was carried out. There is potential for additional recycling/recovery of 10 %.Methods
Three scenarios were proposed for the management of ELV wastes: (1) scenario 1 corresponds to the baseline and refers to the current management, i.e., the 10 % of ELV wastes are shredded whereby some ferrous and non-ferrous metals are recovered and the remaining fraction, called automotive shredder residues (ASR), is landfilled, (2) scenario 2 wherein the ASR fraction is incinerated with energy recovery, and (3) scenario 3 includes the additional dismantling of components for recycling and for energy recovery through solid recovered fuel, to be used as a fuel substitute in the cement industry. The environmental performance of these scenarios was quantified by using the life cycle assessment methodology. Five impact categories were assessed: abiotic resource depletion, climate change, photochemical oxidant creation, acidification, and eutrophication.Results and discussion
Compared to the other scenarios, in scenario 1 no benefits for the impact categories of climate change and eutrophication were observed. Scenario 2 has environmental credits due to the recycling of ferrous and non-ferrous metals and benefits from energy recovery. However, this scenario has a significant impact on climate change due to emissions from thermal oxidation of polymeric materials present in the ASR fraction. A net environmental performance upgrading seems to be ensured by scenario 3, mainly due to replacing fossil fuel by solid recovered fuel.Conclusions
The proposed additional dismantling of ELV (scenario 3) not only brings environmental benefits but also meets the European recovery and recycling targets. The associated increase of dismantling costs can be compensated by the additional recycling material revenues as well as social benefits by a rise in employment. 相似文献733.
Maria João Matos Fernanda Pérez-Cruz Saleta Vazquez-Rodriguez Eugenio Uriarte Lourdes Santana Fernanda Borges Claudio Olea-Azar 《Bioorganic & medicinal chemistry》2013,21(13):3900-3906
In the present work we synthesized a series of hydroxy-3-arylcoumarins (compounds 1–9), some of them previously described as MAO-B selective inhibitors, with the aim of evaluating their antioxidant properties. Theoretical evaluation of ADME properties of all the derivatives was also carried out. From the ORAC-FL, ESR and CV data it was concluded that these derivatives are very good antioxidants, with a very interesting hydroxyl, DPPH and superoxide radicals scavenging profiles. In particular compound 9 is the most active and effective antioxidant of the series (ORAC-FL = 13.5, capacity of scavenging hydroxyl radicals = 100%, capacity of scavenging DPPH radicals = 65.9% and capacity of scavenging superoxide radicals = 71.5%). Kinetics profile for protection fluorescein probe against peroxyl radicals by addition of antioxidant molecule 9 was also performed. Therefore, it can operate as a potential candidate for preventing or minimizing the free radicals overproduction in oxidative-stress related diseases. 相似文献
734.
The aim of this work was to develop a biosensor for toxic amides using whole cells of Pseudomonas. aeruginosa containing amidase activity, which catalyses the hydrolysis of amides such as acrylamide producing ammonia and the corresponding organic acid. Whole cells immobilized in several types of membrane in the presence of glutaraldehyde and an ammonium ion-selective electrode, were used for biosensor development. This biosensor exhibited a linear response in the range of 0.1–4.0×10?3 M of acrylamide, a detection limit of 4.48×10?5 M acrylamide, a response time of 55 s, a sensitivity of 58.99 mV mM?1 of acrylamide and a maximum t1/2 of 54 days. The selectivity of this biosensor towards other amides was investigated, which revealed that it cross-reacted with acetamide and formamide, but no activity was detected with phenylacetamide, p-nitrophenylacetamide and acetanilide. It was successfully used for quantification of acrylamide in real industrial effluents and recovery experiments were carried out which revealed an average substrate recovery of 93.3%. The biosensor is cheap since whole cells of P. aeruginosa can be used as source of amidase activity. 相似文献
735.
Romain Dugravier Florence Tubach Thomas Saias Nicole Guedeney Blandine Pasquet Diane Purper-Ouakil Susana Tereno Bertrand Welniarz Joana Matos the CAPEDP study group Antoine Guedeney Tim Greacen 《PloS one》2013,8(8)
Context
Postnatal maternal depression (PND) is a significant risk factor for infant mental health. Although often targeted alongside other factors in perinatal home-visiting programs with vulnerable families, little impact on PND has been observed.Objective
This study evaluates the impact on PND symptomatology of a multifocal perinatal home-visiting intervention using psychologists in a sample of women presenting risk factors associated with infant mental health difficulties.Methods
440 primiparous women were recruited at their seventh month of pregnancy. All were future first-time mothers, under 26, with at least one of three additional psychosocial risk factors: low educational level, low income, or planning to raise the child without the father. The intervention consisted of intensive multifocal home visits through to the child’s second birthday. The control group received care as usual. PND symptomatology was assessed at baseline and three months after birth using the Edinburgh Postnatal Depression Scale (EPDS).Results
At three months postpartum, mean (SD) EPDS scores were 9.4 (5.4) for the control group and 8.6 (5.4) for the intervention group (p = 0.18). The difference between the mean EPDS scores was 0.85 (95% CI: 0.35; 1.34). The intervention group had significantly lower EPDS scores than controls in certain subgroups: women with few depressive symptoms at inclusion (EPDS <8): difference = 1.66 (95%CI: 0.17; 3.15), p = 0.05, adjusted for baseline EPDS score), women who were planning to raise the child with the child’s father: difference = 1.45 (95%CI: 0.27; 2.62), p = 0.04 (adjusted); women with a higher educational level: difference = 1.59 (95%CI: 0.50; 2.68) p = 0.05 (adjusted).Conclusion
CAPEDP failed to demonstrate an overall impact on PND. However, post-hoc analysis reveals the intervention was effective in terms of primary prevention and in subgroups of women without certain risk factors. Effective overall reduction of PND symptomatology for young, first-time mothers presenting additional psychosocial risk factors may require more tailored interventions.Trial registration
ClinicalTrials.gov Promoting Parental Skills and Enhancing Attachment in Early Childhood (CAPEDP) NCT00392847相似文献736.
Maria Luísa Lobo Francisco Esteves Bruno de Sousa Fernando Cardoso Melanie T. Cushion Francisco Antunes Olga Matos 《PloS one》2013,8(8)
Pneumocystis pneumonia (PcP) is a major cause of mortality and morbidity in immunocompromised patients. There are limited alternative therapeutic choices to trimethoprim-sulfamethoxazole (TMP-SMX) which is the standard first line therapy/prophylaxis for PcP. The efficacy of low doses of caspofungin and caspofungin in association with TMP-SMX standard-prophylactic dose was evaluated in an experimental model of Pneumocystis. Susceptibility of Pneumocystis spp. to low doses of caspofungin and caspofungin/TMP-SMX was evaluated in Balb/c immunosuppressed mice, infected intranasally with P. murina. Caspofungin was administered once daily at 0.1 mg/kg, 0.05 mg/kg, and 0.001 mg/kg and TMP-SMX was administered by oral gavage (12.25 mg/62.5 mg/day), for 21 days. Efficacy was calculated based on the reduction in organism burden determined through quantitative fluorescent-based real-time PCR (qPCR). Serum β-1,3-D-glucan was measured as an additional marker of infection. The present data showed that caspofungin demonstrated anti-Pneumomocystis effect. However, the doses administrated were too low to achieve Pneumocystis eradication, which suggests that echinocandin treatment should not be administrated as mono-therapy. After 21 days of treatment, P. murina was not detected in the lungs of mice with either TMP-SMX or caspofungin/TMP-SMX. The results showed that, even at the lowest concentrations tested, the efficacy of caspofungin in association with TMP-SMX was higher than the efficacy of either drug used alone. The administration of caspofungin/TMP-SMX was at least 1.4 times more effective against P. murina infection than TMP-SMX used alone. The most promising result was achieved with the combination of caspofungin 0.05 mg/kg/day with TMP-SMX 12.5 mg–62.5 mg/day, which reduced the parasite burden to undetectable levels immediately at the 14th day of treatment, showing a highly marked anti-Pneumomocystis effect. These data suggest that the administration of low doses of caspofungin in combination with low doses of TMP-SMX may provide an improved treatment protocol for Pneumocystis infection clearance. 相似文献
737.
Zizhen Zhang Steven Cordeiro Matos Sonia Jego Antoine Adamantidis Philippe Séguéla 《PloS one》2013,8(6)
Optimal norepinephrine levels in the prefrontal cortex (PFC) increase delay-related firing and enhance working memory, whereas stress-related or pathologically high levels of norepinephrine are believed to inhibit working memory via α1 adrenoceptors. However, it has been shown that activation of Gq-coupled and phospholipase C-linked receptors can induce persistent firing, a cellular correlate of working memory, in cortical pyramidal neurons. Therefore, despite its importance in stress and cognition, the exact role of norepinephrine in modulating PFC activity remains elusive. Using electrophysiology and optogenetics, we report here that norepinephrine induces persistent firing in pyramidal neurons of the PFC independent of recurrent fast synaptic excitation. This persistent excitatory effect involves presynaptic α1 adrenoceptors facilitating glutamate release and subsequent activation of postsynaptic mGluR5 receptors, and is enhanced by postsynaptic α2 adrenoceptors inhibiting HCN channel activity. Activation of α2 adrenoceptors or inhibition of HCN channels also enhances cholinergic persistent responses in pyramidal neurons, providing a mechanism of crosstalk between noradrenergic and cholinergic inputs. The present study describes a novel cellular basis for the noradrenergic control of cortical information processing and supports a synergistic combination of intrinsic and network mechanisms for the expression of mnemonic properties in pyramidal neurons. 相似文献
738.
L Kakkola O V Denisova J Tynell J Viili?inen T Ysenbaert R C Matos A Nagaraj T ?hman S Kuivanen H Paavilainen L Feng B Yadav I Julkunen O Vapalahti V Hukkanen J Stenman T Aittokallio E W Verschuren P M Ojala T Nyman X Saelens K Dzeyk D E Kainov 《Cell death & disease》2013,4(7):e742
ABT-263 and its structural analogues ABT-199 and ABT-737 inhibit B-cell lymphoma 2 (Bcl-2), BCL2L1 long isoform (Bcl-xL) and BCL2L2 (Bcl-w) proteins and promote cancer cell death. Here, we show that at non-cytotoxic concentrations, these small molecules accelerate the deaths of non-cancerous cells infected with influenza A virus (IAV) or other viruses. In particular, we demonstrate that ABT-263 altered Bcl-xL interactions with Bcl-2 antagonist of cell death (Bad), Bcl-2-associated X protein (Bax), uveal autoantigen with coiled-coil domains and ankyrin repeats protein (UACA). ABT-263 thereby activated the caspase-9-mediated mitochondria-initiated apoptosis pathway, which, together with the IAV-initiated caspase-8-mediated apoptosis pathway, triggered the deaths of IAV-infected cells. Our results also indicate that Bcl-xL, Bcl-2 and Bcl-w interact with pattern recognition receptors (PRRs) that sense virus constituents to regulate cellular apoptosis. Importantly, premature killing of IAV-infected cells by ABT-263 attenuated the production of key pro-inflammatory and antiviral cytokines. The imbalance in cytokine production was also observed in ABT-263-treated IAV-infected mice, which resulted in an inability of the immune system to clear the virus and eventually lowered the survival rates of infected animals. Thus, the results suggest that the chemical inhibition of Bcl-xL, Bcl-2 and Bcl-w could potentially be hazardous for cancer patients with viral infections. 相似文献
739.
Andreia A Santos Célia C Lopes Jorge R Ribeiro Liliana R Martins Joana C Santos Irina F Amorim Fátima Gärtner Augusto J Matos 《BMC veterinary research》2013,9(1):1-11
Background
Although several histopathological and clinical features of canine mammary gland tumours have been widely studied from a prognostic standpoint, considerable variations in tumour individual biologic behaviour difficult the definition of accurate prognostic factors. It has been suggested that the malignant behaviour of tumours is the end result of several alterations in cellular physiology that culminate in tumour growth and spread. Accordingly, the aim of this study was to determine, using a multivariable model, the independent prognostic value of several immunohistochemically detected tumour-associated molecules, such as MMP-9 and uPA in stromal cells and Ki-67, TIMP-2 and VEGF in cancer cells.Results
Eighty-five female dogs affected by spontaneous malignant mammary neoplasias were followed up for a 2-year post-operative period. In univariate analysis, tumour characteristics such as size, mode of growth, regional lymph node metastases, tumour cell MIB-1 LI and MMP-9 and uPA expressions in tumour-adjacent fibroblasts, were associated with both survival and disease-free intervals. Histological type and grade were related with overall survival while VEGF and TIMP-2 were not significantly associated with none of the outcome parameters. In multivariable analysis, only a MIB-1 labelling index higher than 40% and a stromal expression of MMP-9 higher than 50% retained significant relationships with poor overall and disease-free survival.Conclusions
The results of this study indicate that MMP-9 and Ki-67 are independent prognostic markers of canine malignant mammary tumours. Furthermore, the high stromal expressions of uPA and MMP-9 in aggressive tumours suggest that these molecules are potential therapeutic targets in the post-operative treatment of canine mammary cancer. 相似文献740.
M. C. Arias Christiane Atteke S. C. Augusto J. Bailey Pilar Bazaga Luciano B. Beheregaray Laure Benoit Rumsaïs Blatrix Céline Born R. M. Brito Hai‐kui Chen Sara Covarrubias Clara de Vega Champlain Djiéto‐Lordon Marie‐Pierre Dubois F. O. Francisco Cristina García P. H. P. Gonçalves Clementina González Carla Gutiérrez‐Rodríguez Michael P. Hammer Carlos M. Herrera H. Itoh S. Kamimura H. Karaoglu S. Kojima Shou‐Li Li Hannah J. Ling Pável F. Matos‐Maraví Doyle McKey Judicaël Mezui‐M'Eko Juan Francisco Ornelas R. F. Park María I. Pozo Satu Ramula Cristina Rigueiro Jonathan Sandoval‐Castillo L. R. Santiago Miyuki M. Seino Chang‐Bing Song H. Takeshima Anti Vasemägi C. R. Wellings Ji Yan Du Yu‐Zhou Chang‐Rong Zhang Tian‐Yun Zhang 《Molecular ecology resources》2013,13(4):760-762
This article documents the addition of 142 microsatellite marker loci to the Molecular Ecology Resources database. Loci were developed for the following species: Agriophyllum squarrosum, Amazilia cyanocephala, Batillaria attramentaria, Fungal strain CTeY1 (Ascomycota), Gadopsis marmoratus, Juniperus phoenicea subsp. turbinata, Liriomyza sativae, Lupinus polyphyllus, Metschnikowia reukaufii, Puccinia striiformis and Xylocopa grisescens. These loci were cross‐tested on the following species: Amazilia beryllina, Amazilia candida, Amazilia rutila, Amazilia tzacatl, Amazilia violiceps, Amazilia yucatanensis, Campylopterus curvipennis, Cynanthus sordidus, Hylocharis leucotis, Juniperus brevifolia, Juniperus cedrus, Juniperus osteosperma, Juniperus oxycedrus, Juniperus thurifera, Liriomyza bryoniae, Liriomyza chinensis, Liriomyza huidobrensis and Liriomyza trifolii. 相似文献