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This paper describes the details of the design of a solar water disinfection system based on a small-scale linear Fresnel reflector. The proposed system consists of a small-scale linear Fresnel reflector, a filtering system, two disinfection units, a heat exchanger, a compressed air system and the control system. A detailed mathematical model has been developed and solved through an iterative procedure. The system has been studied under different operating conditions, such as beam solar irradiance (the beam solar irradiance on a horizontal surface, corresponding to solar noon, varies from 325 to 798 W m-2, for winter solstice and summer solstice, respectively), ambient temperature (the ambient temperature varies between 19 and 29 °C at the summer solstice and from 8 to 16 °C at the winter solstice), thermal fluid flow rate (2200 L h-1, 2400 L h-1, 2600 L h-1, and 2800 L h-1) and water temperature at the outlet of the filtered water tank (8 °C, 12 °C, 16 °C, and 20 °C). The performance of the system has been studied as a function of the temperature of the thermal fluid of the small-scale linear Fresnel reflector, the water temperature of the disinfection unit, the filling and emptying of inertia tanks, clean water productivity and the daily cumulative productivity of clean water. Numerical simulations reveal that the maximum values of cumulative daily productivity of clean water were 357.14 (L m-2 day-1) at 100 (°C) and 198.41 (L m-2 day-1) at 100 (°C) for summer solstice and winter solstice, respectively, in Almeria (Spain), for a thermal fluid flow rate of 2400 L h-1. Values much higher than those obtained by other systems. The inclusion of a heat exchanger in this system significantly increases its productivity. Small-scale linear Fresnel reflector thermal fluid temperature, disinfection unit water temperature, clean water productivity and daily cumulative clean water productivity decreased with increasing thermal fluid flow rate above 2400 L h-1. On the other hand, the water temperature at the outlet of the filtered water tank between 8 and 20 °C has a negligible influence on the small-scale linear Fresnel reflector thermal fluid temperature values, disinfection unit water temperature, clean water productivity and daily cumulative clean water productivity. It is concluded that the proposed solar system offers an energy efficient and environmentally friendly water treatment method.
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In times when environmental concerns are on the rise and the search of ways to reduce waste generation and to create a circular economy is booming, Nature Based Solutions (NBSs) play a very important role. Vegetation Filters (VFs) are a type of Land Application System (LAS) in which wastewater is used to irrigate a forestry plantation to treat the water and produce biomass. VFs show multiple benefits that render this technology a suitable solution for wastewater treatment, especially for scattered populations or isolated buildings that lack of connection to sewer systems. This review aims to provide a comprehensive state of the art of VF implementation, highlighting the do's and don'ts for a successful performance focusing on those factors that are essential to water treatment. Results show that VFs have a great treatment capacity when all involving factors are considered, and their efficiency tends to increase with time, as the VF develops and "gets older". Indeed, the presence of fine-textured soils, the selection of a proper vegetation species, the use of pre-treated wastewater and a water balance-based irrigation schedule alternating wetting and -drying cycles are all factors that help to achieve the best performance. However, it is necessary to design and follow a simple but rigorous operation and maintenance schedule to avoid system failure, which could lead to NO3-N leaching towards groundwater.
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Água Subterrânea , Purificação da Água , Solo , Águas Residuárias/análiseRESUMO
Tumours diagnosed in three aged captive aye-ayes (Daubentonia madagascariensis), held in two different institutions, are described. A cerebral glioblastoma was diagnosed based on histological and immunohistochemical findings in one of the animals following initial presentation with bilateral mydriasis, absent pupillary reflex, head tilt and ataxia. A second animal was humanely destroyed due to impaired locomotion associated with spondylosis and a post-mortem diagnosis of cholangiocarcinoma was made based on histology with further confirmation with immunohistochemical labelling for cytokeratin 7. A third aye-aye suffering from dental disease was diagnosed with an oral squamous cell carcinoma following an excisional biopsy from a non-healing wound in the lip. Due to progression of the neoplasia the animal was humanely destroyed and post-mortem examination revealed the presence on an additional unilateral phaeochromocytoma.
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Neoplasias/veterinária , Strepsirhini , Animais , Feminino , MasculinoRESUMO
It is commonly accepted that the toxicity of carbonaceous particulate matter (PM) is due to the production of reactive oxygen species (ROS) which induce biological damage in the exposed cells. It is also known that PM produced during the combustion processes consists of a carbonaceous core "dressed" with other organic and/or inorganic materials. In spite of this knowledge, the role of these materials in the production of ROS has not yet been clear. This work aims at understanding whether "naked" carbonaceous particles are capable of forming ROS either in cell-free or in-cell systems. The problem has been treated based on the data collected from pure graphite samples of different sizes obtained by ball-milling pure graphite for various lengths of time. The experimental approach considered Raman, ESR (spin trapping), cell viability and fluorescence spectroscopy measurements. These techniques allowed us to carry out measurements both in cell and cell-free systems and the results consistently indicate that also pure naked carbonaceous particles can catalyze the electron transfer that produces superoxide ions. The process depends on the particle size and enlightens the role of the edges of the graphitic platelets. Evidence has been collected that even "naked" graphitic nanoparticles are capable of producing ROS and decreasing the cell viability thus representing a potential danger to human health.
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Sistema Livre de Células , Grafite/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Poluentes Atmosféricos , Linhagem Celular , Humanos , Tamanho da Partícula , Material ParticuladoRESUMO
Several studies have demonstrated that allelic variants related to inflammation and the immune system may increase the risk for major depressive disorder (MDD) and reduce patient responsiveness to antidepressant treatment. Proteasomes are fundamental complexes that contribute to the regulation of T-cell function. Only one study has shown a putative role of proteasomal PSMA7, PSMD9 and PSMD13 genes in the susceptibility to an antidepressant response, and sparse data are available regarding the potential alterations in proteasome expression in psychiatric disorders such as MDD. The aim of this study was to clarify the role of these genes in the mechanisms underlying the response/resistance to MDD treatment. We performed a case-control association study on 621 MDD patients, of whom 390 were classified as treatment-resistant depression (TRD), and we collected peripheral blood cells and fibroblasts for mRNA expression analyses. The analyses showed that subjects carrying the homozygous GG genotype of PSMD13 rs3817629 had a twofold greater risk of developing TRD and exhibited a lower PSMD13 mRNA level in fibroblasts than subjects carrying the A allele. In addition, we found a positive association between PSMD9 rs1043307 and the presence of anxiety disorders in comorbidity with MDD, although this result was not significant following correction for multiple comparisons. In conclusion, by confirming the involvement of PSMD13 in the MDD treatment response, our data corroborate the hypothesis that the dysregulation of the complex responsible for the degradation of intracellular proteins and potentially controlling autoimmunity- and immune tolerance-related processes may be involved in several phenotypes, including the TRD.
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Transtorno Depressivo Maior/genética , Transtorno Depressivo Resistente a Tratamento/genética , Complexo de Endopeptidases do Proteassoma/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The radiation therapy carried out by means of heavy charged particles (such as carbon ions) and neutrons is rapidly becoming widespread worldwide. The success of these radiation therapies relies on the high density of energy released by these particles or by secondary particles produced after primary interaction with matter. The biological damages produced by ionising radiations in tissues and cells depend more properly on the energy released per unit pathlength, which is the linear energy transfer and which determines the radiation quality. To improve the therapy effectiveness, it is necessary to grasp the mechanisms of free radical production and distribution after irradiation with these particles when compared with the photon beams. In this work some preliminary results on the analysis of the spatial distributions of the free radicals produced after exposure of ammonium tartrate crystals to various radiation beams ((60)Co gamma photons and thermal neutrons) were reported. Electron spin resonance analyses were performed by the electron spin echo technique, which allows the determination of local spin concentrations and by double electron-electron resonance technique, which is able to measure the spatial distance distribution (range 1.5-8 nm) among pairs of radicals in solids. The results of these analyses are discussed on the basis of the different distributions of free radicals produced by the two different radiation beams used.
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Radiometria/instrumentação , Radiometria/métodos , Tartaratos/química , Carbono/uso terapêutico , Radioisótopos de Cobalto/química , Cristalização , Espectroscopia de Ressonância de Spin Eletrônica , Elétrons , Radicais Livres , Raios gama , Íons Pesados , Magnetismo , Nêutrons , Fótons , Radiação IonizanteRESUMO
We studied by electron spin echo pulse methods the spin relaxation properties of a phenyl nitronyl nitroxide radical (2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide, PTIO) at X-band in fluid toluene solution in a wide temperature range, and in a water/glycerol 1:1 mixture near room temperature. The relaxation properties of PTIO have been compared with that of Tempone, as a widely used nitroxide. By a new procedure, based on experimental results on the temperature dependences of the relaxation times T(1) and T(2), and on the approximation of an isotropic brownian rotational diffusion, we separated non-secular, spin rotational and residual terms from the transverse relaxation rate to isolate secular and pseudosecular contributions. By comparing the results for the two radicals we found the differences in the magnetic properties that give rise to slower transverse (T(2)) and longitudinal (T(1)) electron spin relaxation for PTIO in the whole temperature range explored in this work.
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BACKGROUND AND AIM: Urinary albumin excretion (UAE) measurement is recommended in the diagnosis and follow-up of the hypertensive patient. The aim of the study was to evaluate the proportion of hypertensives attended in Primary Care who had an evaluation of UAE in the last year, along with the methodology of the measurement. PATIENTS AND METHODS: A total of 958 investigators consecutively recruited 4786 hypertensives (first five patients who attended). When present, the measurement of UAE during the last year was obtained from clinical records. In those having this measurement, the type of urine collection (24hours, nighttime or morning spot), as well as the value and units of measure (mg/24h, µg/min, mg/g or mg/L) were recorded. RESULTS: Mean age was 66 years. 51% were men and 49% women. UAE was determined in 2301 patients (48.1%). In 329, 24-hour urine was collected, nighttime urine in 122 and in 1850 the collection came from a morning spot sample. However, only 696 patients from the latter group had the value of albumin corrected by the creatinine excretion. Thus, only 24% of hypertensive patients had a valid UAE measurement (mg/24h, µg/min or mg/g). Prevalence of microalbuminuria was 36%. The UAE determination was associated with older age, obesity, diabetes and better blood pressure control rates. CONCLUSION: Only half of hypertensive patients have a UAE measurement and in only 1 out of 4 a validated methodology has been used. It seems necessary a reinforcement of the messages contained in guidelines, as well as its applicability to any particular setting in order to promote a generalized and correct evaluation of UAE in hypertension.
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Albuminúria/diagnóstico , Fidelidade a Diretrizes/estatística & dados numéricos , Hipertensão/complicações , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Idoso , Albuminúria/urina , Estudos Transversais , Feminino , Humanos , Hipertensão/urina , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde , EspanhaRESUMO
RNA editing is a post-transcriptional process with an important role in gene modification. This editing process involves site-selective deamination of adenosine into inosine in the pre-mRNA, leading to the alteration of translation codons and splicing sites in nuclear transcripts, thereby enabling functionally distinct proteins to arise from a single gene. One important instance is the neuron editing of the ionotropic glutamate receptors (iGluRs). GluRs play a key role in excitatory synaptic transmission and plasticity in the central nervous system (CNS); their channel properties are largely dictated by the subunit composition of the tetrameric receptors. AMPA/kainate channels are assembled from GluA1-4 AMPA or GluK1-5 kainate receptor subunits. In particular, three of the four AMPA and two of the five kainate receptor subunits are subject to RNA editing. The editing positions have been named on the basis of the amino acid substitutions, such as the Q/R site in AMPA GluA2; the Q/R site in GluK1 and GluK2; the R/G site in GluA2, GluA3, and GluA4; and the I/V and Y/C sites in GluK2. These amino acid changes lead to profound alterations of the channel properties. This paper reviews the most relevant data showing the importance of glutamate receptor RNA editing in finely tuning glutamatergic neurotransmission in the normal CNS and following alterations of the editing process in association with disease phenotypes. Overall, these data indicate that a highly regulated process of glutamate receptor editing is of key importance in the proper function of neuronal cells and in their ability to adapt and modulate synaptic function.
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Doenças do Sistema Nervoso Central/genética , Edição de RNA , Receptores Ionotrópicos de Glutamato/genética , Animais , Doenças do Sistema Nervoso Central/metabolismo , Humanos , Receptores Ionotrópicos de Glutamato/metabolismoRESUMO
The term "RNA editing" is used to identify any mechanism responsible for producing mRNA molecules with sequence information not specifically encoded in the DNA. RNA editing is therefore an important event in gene modification, which takes place at a post-transcriptional level. The molecular mechanism of RNA editing involves site-selective deamination of adenosine to inosine in pre-mRNA, which leads to altering translation codons and splicing in nuclear transcripts, whereby functionally distinct proteins can be produced from a single gene. The mammalian editing enzymes ADARs (adenosine deaminases acting on RNA) are widely expressed in brain and other tissues: however, up until now their substrates have mainly been found in the Central Nervous System (CNS). Of particular relevance in the CNS is the editing occurring at the ionotropic glutamate receptors (GluRs) level. Three AMPA and two Kainate receptors are subject to RNA editing. The consequence of this process is the substitution of specific amino acids in functionally critical positions of the receptors. Depending on the GluR involved, the consequences of editing will involve: activation and/or inhibition of splicing sites; modulation of the trafficking of the receptor to the plasma membrane; the process of tetramerization of the receptor subunits; modification of the ions passage through the receptor channel; modulation of the desensitization and action potential recovery times. All these events are specific to the different GluRs and are genetically and developmentally controlled. RNA editing is therefore a crucial event involved in controlling transmission of the action potential at the postsynaptic level. This modulation involves the transmission of all sensory stimuli to the CNS and gives rise to the "Sensotype". The Sensotype therefore defines the "way" in which the information acquired from the environment by the sensory systems is transmitted to the brain. The signals and inputs deriving from the Sensotype are transmitted to the brain, which processes and stores these signals thus generating the "Brainotype". Brainotype and Sensotype are genetically and environmentally determined; they are individually unique and specific to every living organism with a nervous system. Their characteristics are, at least in part, dependent on the modulation of the "RNA editing" process since glutamate receptors represent the main neurotransmitter system in the CNS.
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Engenharia Genética/métodos , Proteínas do Tecido Nervoso/genética , Doenças do Sistema Nervoso/genética , Plasticidade Neuronal/genética , RNA/genética , Células Receptoras Sensoriais/fisiologia , Transmissão Sináptica/genética , Animais , Predisposição Genética para Doença/genética , Humanos , Fenótipo , Engenharia de Proteínas/métodosRESUMO
Fast excitatory transmission in the vertebrate central nervous system is mediated mainly by L-glutamate. Here we present the genomic organization of the human GRIK2 gene, which codes for the kainate GluR6 receptor subunit, deduced from sequence data present in the public databases and analyzed by bioinformatic tools. By similarity search using the human GluR6 cDNA sequence against non-redundant databases, we found three positive entries (AP002528, AP002529, and AP002530 deposited by Hirakawa et al., 2000) which are part of a BAC contig of about 1 Mb spanning region 6q21. The GRIK2 gene was found to be split into 17 exons, covering about 670 kb of the region. The availability of the data on the genomic organization allowed the study of GRIK2 gene expression by RT-PCR analysis which was performed on human teratocarcinoma cell cultures (NT2) and on mRNA obtained from human hippocampus (Clontech). The study gives evidence for several different splicing variants in addition to the previously cloned human GluR6 cDNA (ID: U16126). The splicing mechanism leading to the different isoforms involves exons 11, 12 and 16. The mRNA containing exon 16 at the 3' end is the homolog to the mouse GluR6-2. The translation of this mRNA would code for a different intracellular C-terminus, as compared to that coded by the known human isoform. The newly identify isoform is the predominant form expressed in human teratocarcinoma NT2 cells. All the newly identified mRNAs isoforms are expressed in NT2 cells and in human hippocampus mRNA at variable levels and would be responsible for the production of five different putative GluR6 receptor subunits, some differing in the C-terminal domains (mouse homolog) and some lacking specific transmembrane domains.
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Processamento Alternativo , Genes/genética , Receptores de Ácido Caínico/genética , Sequência de Aminoácidos , Sequência de Bases , DNA Complementar/química , DNA Complementar/genética , Éxons , Expressão Gênica , Hipocampo/metabolismo , Humanos , Íntrons , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas/genética , Subunidades Proteicas , Precursores de RNA/química , Precursores de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Células Tumorais Cultivadas , Receptor de GluK2 CainatoRESUMO
In the present study, we report the genomic reconstruction of the glutamate receptor GluR5 gene (GRIK1, alias GLUR5; 402 kb) by the use of the data available in public databases. This analysis allowed characterization of the exon-intron boundaries, identification of the gene promoter region, presentation of the putative complete sequences of two GluR5 mRNA isoforms, and definition of the structure of GluR5 pre-mRNA surrounding the Q/R editing site.
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Processamento Alternativo/genética , Éxons/genética , Íntrons/genética , Edição de RNA/genética , Receptores de Glutamato Metabotrópico/genética , Sequência de Bases , Bases de Dados Factuais , Etiquetas de Sequências Expressas , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Isoformas de Proteínas/genética , Precursores de RNA/análise , Precursores de RNA/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Receptor de Glutamato Metabotrópico 5 , Sequências Repetitivas de Ácido Nucleico/genética , Sitios de Sequências RotuladasRESUMO
We present the Human Muscle Gene Map (HMGM), the first comprehensive and updated high-resolution expression map of human skeletal muscle. The 1078 entries of the map were obtained by merging data retrieved from UniGene with the RH mapping information on 46 novel muscle transcripts, which showed no similarity to any known sequence. In the map, distances are expressed in megabase pairs. About one-quarter of the map entries represents putative novel genes. Genes known to be specifically expressed in muscle account for <4% of the total. The genomic distribution of the map entries confirmed the previous finding that muscle genes are selectively concentrated in chromosomes 17, 19, and X. Five chromosomal regions are suspected to have a significant excess of muscle genes. Present data support the hypothesis that the biochemical and functional properties of differentiated muscle cells may result from the transcription of a very limited number of muscle-specific genes along with the activity of a large number of genes, shared with other tissues, but showing different levels of expression in muscle. [The sequence data described in this paper have been submitted to the EMBL data library under accession nos. F23198-F23242.]