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1.
Sci Total Environ ; 612: 81-93, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28846907

RESUMO

Marking petroglyphs with chalk is a common practice to enhance them for documentation and reproduction. Although this procedure has started to be less frequently used, there is no knowledge about the interaction between the rock engravings nor about the effectiveness achieved by the common cleaning procedures of such markers considering the chalk extraction and the induced damage to the rock. This study evaluates the interaction between two chalks of different composition (calcite and gypsum) and a granite on which the majority of NW Iberian Peninsula-petroglyphs are carved. Granitic samples marked with these chalks were subjected to artificial rain events and high temperatures (700°C) related to fires. After each aging test, chemical and physical modifications on the rock were analysed by means of stereomicroscopy, x-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and colour spectrophotometry. Moreover, the evaluation of the effectiveness and harmfulness of several mechanical and chemical cleaning procedures commonly used in the field of cultural heritage conservation was carried out. Both chalks remained at different extent on the surface after the artificial rain events. Water would promote a different penetration-depth of the chalks into the stone, depending on their solubility. High temperatures led to mineral phase transformations of the chalks influencing the interaction with the rock. Regarding cleaning effectiveness, despite a few chalk remains were found in all the cleanings, chemical methods showed higher effectiveness than mechanical procedures even though some of them leave chemical contamination. Benzalkonium chloride can be considered as the cleaner with the best results to extract both types of chalk on granite.

2.
Sci Total Environ ; 584-585: 291-306, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28159305

RESUMO

Black crusts on different substrates (carbonate and silicate stones, cement-based mortar and carbonate detrital deposits) in urban environments were characterized microscopically by analysing their morphologies and compositions. The objective of this article is to study the interaction between the substrate and the crust and the influence of the environmental conditions on the crust development. On the one hand, the internal structure and morphology of each sample were evaluated with stereo and scanning electron microscopies. On the other hand, the black crust composition was accessed by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy in backscattered electron mode combined with energy dispersive x-ray spectroscopy. The results of these analytical techniques provided interesting information about the composition and the mineralogical phases present in the collected black crusts. In most of the cases, gypsum was detected as the main component exhibiting different habits. Calcite was also detected in all the evaluated gypsum black crusts; its presence was attributed to different origins. The substrate-crust interaction was also evaluated, contributing to distinguish different crust development processes in relation to the substrate. In carbonate substrates (limestones, mortar and carbonate detrital deposits), it was detected a continuous diffuse boundary related to the replacement of Ca-carbonate by Ca-sulphate, while this boundary was significantly more defined for the granitic stone. This study shows that the substrate, the presence of different construction materials, (e.g. mortars), the motor exhaust particulate substances and the concentrations of atmospheric pollutants, the marine influence as well as biological or other anthropogenic compounds are decisive factors in the development of the black crust. Some ideas about the establishment of conservation strategies are also shown.

3.
Sci Rep ; 6: 22416, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26935982

RESUMO

We report here the first complete transcriptome analysis of the dorsal (dDG) and ventral dentate gyrus (vDG) of a rat epilepsy model presenting a hippocampal lesion with a strict resemblance to classical hippocampal sclerosis (HS). We collected the dDG and vDG by laser microdissection 15 days after electrical stimulation and performed high-throughput RNA-sequencing. There were many differentially regulated genes, some of which were specific to either of the two sub-regions in stimulated animals. Gene ontology analysis indicated an enrichment of inflammation-related processes in both sub-regions and of axonal guidance and calcium signaling processes exclusively in the vDG. There was also a differential regulation of genes encoding molecules involved in synaptic function, neural electrical activity and neuropeptides in stimulated rats. The data presented here suggests, in the time point analyzed, a remarkable interaction among several molecular components which takes place in the damaged hippocampi. Furthermore, even though similar mechanisms may function in different regions of the DG, the molecular components involved seem to be region specific.


Assuntos
Giro Denteado/metabolismo , Epilepsia/metabolismo , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Esclerose Tuberosa/metabolismo , Animais , Giro Denteado/patologia , Epilepsia/patologia , Masculino , Ratos , Ratos Wistar , Esclerose Tuberosa/patologia
4.
Int J Oral Maxillofac Surg ; 44(10): 1246-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26194770

RESUMO

Hallermann-Streiff syndrome (HSS) is a rare congenital abnormality affecting mostly the head and face area. Craniofacial deformities, which are present in 98-99% of cases, are the principal abnormalities detected. We focus here on a particular subset of these deformities: atrophy of the skin of the centre of the face and nose. Two patients diagnosed with HSS were treated in our department. Both patients underwent nasal lipofilling to treat the atrophy of the nasal skin, as described by Nguyen et al. In both cases, a satisfactory improvement in nasal skin colour and texture was observed. A functional gain was also reported by the parents and observed during follow-up consultations. Lipofilling thus appears to be an excellent option for treating craniofacial deformities in children.


Assuntos
Tecido Adiposo/transplante , Síndrome de Hallermann/cirurgia , Nariz/anormalidades , Nariz/cirurgia , Criança , Pré-Escolar , Humanos , Masculino
5.
Curr Mol Med ; 15(4): 299-311, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25941822

RESUMO

The pineal hormone melatonin controls several physiological functions that reach far beyond the regulation of the circadian rhythm. Moreover, it can be produced in extra-pineal organs such as reproductive organs. The role of melatonin in the mammalian seasonal and circadian rhythm is well known. Nevertheless, its overall effect in male reproductive physiology remains largely unknown. Melatonin is a very powerful endogenous antioxidant that can also be exogenously taken safely. Interestingly, its antioxidant properties have been consistently reported to improve the male reproductive dysfunctions associated with pathological conditions and also with the exposure to toxicants. Nevertheless, the exact molecular mechanisms by which melatonin exerts its action in the male reproductive system remain a matter of debate. Herein, we propose to present an up-to-date overview of the melatonin effects in the male reproductive health and debate future directions to disclose possible sites of melatonin action in male reproductive system. We will discuss not only the role of melatonin during darkness and sleep but also the importance of the antioxidant properties of this hormone to male fertility. Since melatonin readily crosses the physiological barriers, such as the blood-testis barrier, and has a very low toxicity, it appears as an excellent candidate in the prevention and/or treatment of the multiple male reproductive dysfunctions associated with various pathologies.


Assuntos
Antioxidantes/farmacologia , Melatonina/metabolismo , Melatonina/farmacologia , Reprodução/fisiologia , Saúde Reprodutiva , Ritmo Circadiano/fisiologia , Escuridão , Humanos , Masculino , Fotoperíodo , Glândula Pineal/metabolismo
6.
J Appl Microbiol ; 115(2): 319-33, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23437848

RESUMO

Allergic diseases affect up to 30% of the western population, and their prevalence is increasing. Probiotics are able to modulate the mucosal immune response, and clinical trials demonstrated that specific strains, especially lactic acid bacteria (LAB) ones, reduce allergic symptoms. Moreover, the use of recombinant probiotics has been evaluated as possible strategies for the immunotherapy of allergic diseases. The production and delivery of allergens by recombinant LAB in concert with their ability to induce a Th1-type immune response have been shown to be a promising mucosal vaccination strategy in mouse model. The aim of this article is to review the applications of probiotics in allergy immunotherapy with a special focus on recombinant LAB delivering proteins or DNA.


Assuntos
Hipersensibilidade/terapia , Imunoterapia , Probióticos/uso terapêutico , Alérgenos/genética , Alérgenos/imunologia , Animais , Bifidobacterium/genética , DNA/administração & dosagem , Humanos , Hipersensibilidade/imunologia , Imunidade nas Mucosas , Lactobacillus/genética , Camundongos , Hipersensibilidade a Leite/terapia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia
7.
Genet Mol Res ; 11(2): 1146-57, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22614283

RESUMO

Lactic acid bacteria (LAB) are an attractive and safe alternative for the expression of heterologous proteins, as they are nonpathogenic and endotoxin-free organisms. Lactococcus lactis, the LAB model organism, has been extensively employed in the biotechnology field for large-scale production of heterologous proteins, and its use as a "cell factory" has been widely studied. We have been particularly interested in the use of L. lactis for production of heat shock proteins (HSPs), which reportedly play important roles in the initiation of innate and adaptive immune responses. However, this activity has been questioned, as LPS contamination appears to be responsible for most, if not all, immunostimulatory activity of HSPs. In order to study the effect of pure HSPs on the immune system, we constructed recombinant L. lactis strains able to produce and properly address the Mycobacterium leprae 65-kDa HSP (Hsp65) to the cytoplasm or to the extracellular medium, using a xylose-induced expression system. Approximately 7 mg/L recombinant Hsp65 was secreted. Degradation products related to lactococcal HtrA activity were not observed, and the Limulus amebocyte lysate assay demonstrated that the amount of LPS in the recombinant Hsp65 preparations was 10-100 times lower than the permitted levels established by the U.S. Food and Drug Administration. These new L. lactis strains will allow investigation of the effects of M. leprae Hsp65 without the interference of LPS; consequently, they have potential for a variety of biotechnological, medical and therapeutic applications.


Assuntos
Proteínas de Bactérias/genética , Chaperonina 60/genética , Lactococcus lactis/metabolismo , Mycobacterium leprae/metabolismo , Sequência de Bases , Clonagem Molecular , Primers do DNA , Lactococcus lactis/genética , Mycobacterium leprae/genética , Reação em Cadeia da Polimerase , Proteínas Recombinantes/genética
8.
Eur J Neurol ; 17(5): 692-5, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20050900

RESUMO

BACKGROUND: Cognitive tests are known to be influenced by language, culture and education. In addition, there may be an impact of 'epoch' in cognition, because there is secular increase in scores of IQ tests in children. If we assume this is a long lasting process, then it should persist later in life. METHODS: To test this hypothesis, we compared the performance of two cohorts of individuals (>or=50 years of age), evaluated 20 years apart using the Mini-Mental State Examination (MMSE). RESULTS: Study population included 135 participants in 1988 and 411 in 2008. MMSE scores were higher in 2008 than in 1988 for literacy x age-matched subgroups, the difference being significant for participants with lower literacy. Score variance was explained by literacy (beta = 0.479, t = 14.598, P = 0.00), epoch (beta = 0.34, t = 10.33, P = 0.00) and age (beta = -0.142, t = -4.184, P = 0.00). CONCLUSION: The present results are in accordance with a lifelong secular improvement in cognitive performance. The operational cut-off values may change with time, which may have clinical impact in the diagnosis of disorders like mild cognitive impairment or dementia.


Assuntos
Transtornos Cognitivos/diagnóstico , Demência/diagnóstico , Testes Neuropsicológicos/normas , Idoso , Envelhecimento/psicologia , Cognição/fisiologia , Transtornos Cognitivos/classificação , Transtornos Cognitivos/psicologia , Estudos de Coortes , Cultura , Demência/classificação , Demência/psicologia , Avaliação da Deficiência , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
9.
Protein Pept Lett ; 15(4): 327-32, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18473942

RESUMO

A precursor of ConBr, a glucose/mannose-binding plant lectin, was expressed in the yeast Pichia pastoris. Western blot analysis of transformed cells detected an intracellularly recombinant protein band with ca. 34.5 kDa. The recombinant protein was apparently active as suggested by its strong interaction with the mannose-rich yeast cell debris.


Assuntos
Pichia/genética , Lectinas de Plantas/biossíntese , Canavalia , Clonagem Molecular , Expressão Gênica , Vetores Genéticos , Glucana Endo-1,3-beta-D-Glucosidase/metabolismo , Complexos Multienzimáticos/metabolismo , Nistatina/metabolismo , Nistatina/farmacologia , Peptídeo Hidrolases/metabolismo , Pichia/metabolismo , Lectinas de Plantas/isolamento & purificação , Proteínas Recombinantes/biossíntese , Transformação Genética
10.
Bioinformatics ; 21(24): 4427-9, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16249264

RESUMO

SUMMARY: This report describes an algorithm (intensity-dependent selection of expression ratios or ISER) developed to analyse DNA array data by optimizing the selection of genes with the most significant variations in expression amongst two RNA samples. The algorithm is designed for use when little or no replication of array hybridizations is available.


Assuntos
Algoritmos , Análise de Sequência com Séries de Oligonucleotídeos/estatística & dados numéricos , Biologia Computacional , Bases de Dados de Ácidos Nucleicos , Perfilação da Expressão Gênica/estatística & dados numéricos , Dinâmica não Linear , Curva ROC , Software
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