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1.
Sci Total Environ ; 652: 320-329, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30366333

RESUMO

The AQUACROSS project was an unprecedented effort to unify policy concepts, knowledge, and management of freshwater, coastal, and marine ecosystems to support the cost-effective achievement of the targets set by the EU Biodiversity Strategy to 2020. AQUACROSS aimed to support EU efforts to enhance the resilience and stop the loss of biodiversity of aquatic ecosystems as well as to ensure the ongoing and future provision of aquatic ecosystem services. The project focused on advancing the knowledge base and application of Ecosystem-Based Management. Through elaboration of eight diverse case studies in freshwater and marine and estuarine aquatic ecosystem across Europe covering a range of environmental management problems including, eutrophication, sustainable fisheries as well as invasive alien species AQUACROSS demonstrated the application of a common framework to establish cost-effective measures and integrated Ecosystem-Based Management practices. AQUACROSS analysed the EU policy framework (i.e. goals, concepts, time frames) for aquatic ecosystems and built on knowledge stemming from different sources (i.e. WISE, BISE, Member State reporting within different policy processes, modelling) to develop innovative management tools, concepts, and business models (i.e. indicators, maps, ecosystem assessments, participatory approaches, mechanisms for promoting the delivery of ecosystem services) for aquatic ecosystems at various scales of space and time and relevant to different ecosystem types.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental , Política Ambiental , Europa (Continente) , Eutrofização , Pesqueiros , Água Doce
2.
Geobiology ; 16(3): 279-296, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29485245

RESUMO

Archean hydrothermal environments formed a likely site for the origin and early evolution of life. These are also the settings, however, were complex abiologic structures can form. Low-temperature serpentinization of ultramafic crust can generate alkaline, silica-saturated fluids in which carbonate-silica crystalline aggregates with life-like morphologies can self-assemble. These "biomorphs" could have adsorbed hydrocarbons from Fischer-Tropsch type synthesis processes, leading to metamorphosed structures that resemble carbonaceous microfossils. Although this abiogenic process has been extensively cited in the literature and has generated important controversy, so far only one specific biomorph type with a filamentous shape has been discussed for the interpretation of Archean microfossils. It is therefore critical to precisely determine the full distribution in morphology and size of these biomorphs, and to study the range of plausible geochemical conditions under which these microstructures can form. Here, a set of witherite-silica biomorph synthesis experiments in silica-saturated solutions is presented, for a range of pH values (from 9 to 11.5) and barium ion concentrations (from 0.6 to 40 mmol/L BaCl2 ). Under these varying conditions, a wide range of life-like structures is found, from fractal dendrites to complex shapes with continuous curvature. The size, spatial concentration, and morphology of the biomorphs are strongly controlled by environmental parameters, among which pH is the most important. This potentially limits the diversity of environments in which the growth of biomorphs could have occurred on Early Earth. Given the variety of the observed biomorph morphologies, our results show that the morphology of an individual microstructure is a poor criterion for biogenicity. However, biomorphs may be distinguished from actual populations of cellular microfossils by their wide, unimodal size distribution. Biomorphs grown by diffusion in silica gel can be differentiated by their continuous gradient in size, spatial density, and morphology along the direction of diffusion.


Assuntos
Archaea/química , Archaea/metabolismo , Fenômenos Químicos , Fósseis , Sedimentos Geológicos , Minerais/análise , Dióxido de Silício/análise , Bário/metabolismo , Cristalização , Concentração de Íons de Hidrogênio
3.
Neoplasia ; 3(6): 521-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11774034

RESUMO

17q23 is a frequent site of gene amplification in breast cancer. Several lines of evidence suggest the presence of multiple amplicons on 17q23. To characterize distinct amplicons on 17q23 and localize putative oncogenes, we screened genes and expressed sequence tags (ESTs) in existing physical and radiation hybrid maps for amplification and overexpression in breast cancer cell lines by semiquantitative duplex PCR, semiquantitative duplex RT-PCR, Southern blot, and Northern blot analyses. We identified two distinct amplicons on 17q23, one including TBX2 and another proximal region including RPS6KB1 (PS6K) and MUL. In addition to these previously reported overexpressed genes, we also identified amplification and overexpression of additional uncharacterized genes and ESTs, some of which suggest potential oncogenic activity. In conclusion, we have further defined two distinct regions of gene amplification and overexpression on 17q23 with identification of new potential oncogene candidates. Based on the amplification and overexpression patterns of known and as of yet unrecognized genes on 17q23, it is likely that some of these genes mapping to the discrete amplicons function as oncogenes and contribute to tumor progression in breast cancer cells.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 17/genética , Etiquetas de Sequências Expressas , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Northern Blotting , Southern Blotting , Neoplasias da Mama/patologia , Linhagem Celular Transformada , Transformação Celular Viral , Mapeamento de Sequências Contíguas , DNA de Neoplasias/genética , Feminino , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Oncogenes , Papillomaviridae/fisiologia , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
6.
Can J Anaesth ; 44(8): 836-42, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9260011

RESUMO

PURPOSE: To study the efficacy of neostigmine compared with placebo for the antagonism of neuromuscular blockade at the end of a mivacurium infusion, and to determine its optimal dose. METHODS: One hundred adult patients undergoing an elective surgical procedure received a standardized anaesthetic with 20-30 micrograms.kg-1 alfentanil, a propofol infusion and nitrous oxide. Muscle relaxation was maintained at 90-95% T1 depression with 0.2 mg.kg-1 mivacurium followed by an infusion. Neuromuscular blockade was measured with an integrated evoked electromyogram in response to train-of-four (TOF) stimuli at the ulnar nerve every 20 sec. Patients were randomized into four groups. At the end of surgery, the mivacurium infusion was stopped and patients received, immediately, in a double-blind manner, neostigmine (10, 20, or 40 micrograms.kg-1) or placebo according to a random number table. The T1 and TOF ratio were recorded until adequate recovery of neuromuscular function (TOF ratio > 0.70). During the reversal period, non-invasive blood pressure and heart rate were recorded every minute. The incidence of postoperative nausea and vomiting (PONV) was recorded in the recovery room. RESULTS: Data from 94 patients who completed the protocol were analysed. Compared with placebo, neostigmine 10 micrograms.kg-1 did not reduce the time to TOF > 0.70 (17.0 +/- 5.1 vs 14.6 +/- 4.2 min respectively). However the time was decreased with neostigmine 20 micrograms.kg-1 and 40 micrograms.kg-1 (P < 0.001), but with no difference between these last two groups (11.4 +/- 3.0 and 11.4 +/- 3.5 min respectively). Changes in systolic blood pressure and heart rate were not different between the four groups. Very few PONV events were observed in all groups (global incidence 7.4%). CONCLUSION: Recovery of neuromuscular blockade following a mivacurium infusion is accelerated by neostigmine. A dose of neostigmine 20 micrograms.kg-1 appears optimal with no further reduction in recovery time obtained from a larger dose.


Assuntos
Inibidores da Colinesterase/farmacologia , Isoquinolinas/farmacologia , Neostigmina/farmacologia , Junção Neuromuscular/efeitos dos fármacos , Fármacos Neuromusculares não Despolarizantes/farmacologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mivacúrio , Junção Neuromuscular/fisiologia
7.
Mol Gen Genet ; 262(6): 1103-12, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10660071

RESUMO

RNA14 was identified as a gene involved in premessenger RNA cleavage and polyadenylation. These processing steps take place in the nucleus, but the Rna14p protein is distributed in both the nucleus and the cytoplasm. By subcellular fractionation, we show here that the cytoplasmic fraction is localised in the mitochondria. In order to understand the role played by Rna14p in mitochondria, we have searched for new thermosensitive alleles of RNA14. We isolated thirteen new mutants. Some of them are deficient in mRNA cleavage and polyadenylation at the restrictive temperature - like the first mutant identified (rna14-1). However, others do not appear to be impaired in any of the steps in RNA metabolism investigated, nor do they appear to be involved in the replication or expression of mitochondrial DNA or in respiration. The localisation data strongly suggest that, besides an essential function in mRNA polyadenylation, the Rna14p protein has a non essential function in mitochondrial metabolism.


Assuntos
Proteínas Fúngicas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Alelos , Sequência de Bases , Núcleo Celular/metabolismo , Primers do DNA/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Mitocôndrias/metabolismo , Mutação , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA/genética , Estabilidade de RNA/genética , RNA Fúngico/genética , RNA Fúngico/metabolismo , Proteínas de Ligação a RNA/genética , Saccharomyces cerevisiae/genética , Supressão Genética , Temperatura , Fatores de Poliadenilação e Clivagem de mRNA
8.
Mol Genet Genomics ; 267(4): 515-25, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12111559

RESUMO

In Saccharomyces cerevisiae, Rna14 protein is involved in both cleavage and polyadenylation of mRNA in the nucleus. Previous work has demonstrated that this protein is also localized in mitochondria. Moreover, all known rna14 mutants can be separated into two distinct classes: the poly(A)-negative class, which contains mutants that are deficient in mRNA 3'-end processing, and the poly(A)-positive class, which includes those mutants that are not impaired in any of the steps in mRNA metabolism investigated. This suggests that in addition to its involvement in mRNA polyadenylation, Rna14p could have a second function related to mitochondrial metabolism. Here we investigated the regulation of RNA14 by characterizing the rna14-5 mutant, which is the only poly(A)-positive allele that also overproduces the RNA14 mRNA. We showed that both deregulation of RNA14 transcription and modification of RNA14 mRNA stability contribute to the strong accumulation of the transcripts in this mutant. Surprisingly, the RNA14 promoter itself is not essential for this phenotype of the rna14-5 mutant. However, the 3' UTR of the mRNA is necessary for overproduction of the transcripts, although it is not sufficient to deregulate a reporter gene by itself. Site-directed mutagenesis experiments provided additional data suggesting that the rna14-5 mutation acts at the protein level rather than modifying the properties of the RNA14 transcripts themselves. A tentative model accounting for the data is discussed, in light of the proposed extranuclear function of the Rna14p and its mitochondrial localization.


Assuntos
Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA , Regiões 3' não Traduzidas , Alelos , Sequência de Bases , DNA Fúngico/genética , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas , Processamento Pós-Transcricional do RNA , Estabilidade de RNA , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica
9.
Mol Gen Genet ; 252(6): 700-8, 1996 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-8917313

RESUMO

SSM4 was isolated as a suppressor of rna14-1, a mutant involved in nuclear mRNA maturation. In order to isolate genes interacting with SSM4, we have searched for mutants that are syntheticlethal in association with an SSM4 deletion. Among the mutants obtained, one, named sls1-1, shows a pet- phenotype. We have cloned and sequenced this gene. It encodes a protein with a calculated molecular mass of 73 kDa. This protein contains a mitochondrial targeting presequence but does not show homology with other known proteins. Deletion of SLS1 does not affect cell viability on glucose but is lethal on a non-fermentable medium. The Sls1p protein does not appear to be involved in mitochondrial DNA replication, transcription, or in RNA splicing maturation or stability. We have also tagged this protein and localized it in mitochondria. Treatment with alkaline carbonate does not extract this protein from mitochondria, suggesting strongly that it is a mitochondrial integral membrane protein. Thus, the SLS1 gene, encodes a mitochondrial integral membrane protein and is paradoxically synlethal in association with a deletion of the SSM4 gene, which encodes an integral nuclear membrane protein.


Assuntos
Genes Fúngicos , Mitocôndrias/metabolismo , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Genes Letais , Dados de Sequência Molecular , RNA/metabolismo , RNA Mitocondrial , Saccharomyces cerevisiae/metabolismo , Deleção de Sequência , Supressão Genética
10.
Proteomics ; 1(10): 1303-19, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11721642

RESUMO

We have developed a comprehensive approach to identifying molecular changes in lung cancer that includes both genomic and proteomic analyses. The related effort has produced a large amount of data pertaining to gene expression at the RNA and protein levels. As a result, we have constructed a database that contains protein expression data on lung cancer as well as other relevant data including DNA microarray derived data. A large number of proteins that are expressed in different types of lung cancer have been identified and have been correlated with the expression measures for their corresponding genes at the RNA level. The database is intended to facilitate our effort at developing novel classification schemes for lung cancer and the identification of novel markers for early diagnosis.


Assuntos
Bases de Dados de Proteínas , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Proteoma/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Pequenas/metabolismo , Processamento Eletrônico de Dados/métodos , Eletroforese em Gel Bidimensional , Humanos , Internet , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Genome Res ; 11(8): 1453-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11483587

RESUMO

There is substantial interest in implementing technologies that allow comparisons of whole genomes of individuals and of tissues and cell populations. Restriction landmark genome scanning (RLGS) is a highly resolving gel-based technique in which several thousand fragments in genomic digests are visualized simultaneously and quantitatively analyzed. The widespread use of RLGS has been hampered by difficulty in deriving sequence information for displayed fragments and a lack of whole-genome sequence-based framework for interpreting RLGS patterns. We have developed informatics tools for comparisons of sample derived RLGS patterns with patterns predicted from the human genome sequence and displayed as Virtual Genome Scans (VGS). The tools developed allow sequence prediction of fragments in RLGS patterns obtained with different restriction enzyme combinations. The utility of VGS is demonstrated by the identification of restriction fragment length polymorphisms, and of amplifications, deletions, and methylation changes in tumor-derived CpG islands and the characterization of an amplified region in a breast tumor that spanned <230 kb on 17q23.


Assuntos
Genoma Humano , Mapeamento por Restrição/métodos , Neoplasias da Mama/genética , Linhagem Celular Transformada , Cromossomos Humanos Par 17/genética , Biologia Computacional/métodos , Bases de Dados Factuais , Amplificação de Genes/genética , Humanos , Reação em Cadeia da Polimerase/métodos , Células Tumorais Cultivadas
12.
Hum Mol Genet ; 10(25): 2917-31, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11741835

RESUMO

ICF (immunodeficiency, centromeric region instability and facial anomalies) is a recessive disease caused by mutations in the DNA methyltransferase 3B gene (DNMT3B). Patients have immunodeficiency, chromosome 1 (Chr1) and Chr16 pericentromeric anomalies in mitogen-stimulated lymphocytes, a small decrease in overall genomic 5-methylcytosine levels and much hypomethylation of Chr1 and Chr16 juxtacentromeric heterochromatin. Microarray expression analysis was done on B-cell lymphoblastoid cell lines (LCLs) from ICF patients with diverse DNMT3B mutations and on control LCLs using oligonucleotide arrays for approximately 5600 different genes, 510 of which showed a lymphoid lineage-restricted expression pattern among several different lineages tested. A set of 32 genes had consistent and significant ICF-specific changes in RNA levels. Half of these genes play a role in immune function. ICF-specific increases in immunoglobulin (Ig) heavy constant mu and delta RNA and cell surface IgM and IgD and decreases in Ig(gamma) and Ig(alpha) RNA and surface IgG and IgA indicate inhibition of the later steps of lymphocyte maturation. ICF-specific increases were seen in RNA for RGS1, a B-cell specific inhibitor of G-protein signaling implicated in negative regulation of B-cell migration, and in RNA for the pro-apoptotic protein kinase C eta gene. ICF-associated decreases were observed in RNAs encoding proteins involved in activation, migration or survival of lymphoid cells, namely, transcription factor negative regulator ID3, the enhancer-binding MEF2C, the iron regulatory transferrin receptor, integrin beta7, the stress protein heme oxygenase and the lymphocyte-specific tumor necrosis factor receptor family members 7 and 17. No differences in promoter methylation were seen between ICF and normal LCLs for three ICF upregulated genes and one downregulated gene by a quantitative methylation assay [combined bisulfite restriction analysis (COBRA)]. Our data suggest that DNMT3B mutations in the ICF syndrome cause lymphogenesis-associated gene dysregulation by indirect effects on gene expression that interfere with normal lymphocyte signaling, maturation and migration.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Síndromes de Imunodeficiência/genética , Mutação , RNA/metabolismo , Linhagem Celular , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 16/genética , Metilação de DNA , Citometria de Fluxo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Linfócitos/patologia , Proteínas de Membrana/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Regiões Promotoras Genéticas , Síndrome , DNA Metiltransferase 3B
13.
Appl Environ Microbiol ; 70(8): 4961-70, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15294836

RESUMO

We designed and successfully implemented the use of in situ-synthesized 45-mer oligonucleotide DNA microarrays (XeoChips) for genome-wide expression profiling of Burkholderia xenovorans LB400, which is among the best aerobic polychlorinated biphenyl degraders known so far. We conducted differential gene expression profiling during exponential growth on succinate, benzoate, and biphenyl as sole carbon sources and investigated the transcriptome of early-stationary-phase cells grown on biphenyl. Based on these experiments, we outlined metabolic pathways and summarized other cellular functions in the organism relevant for biphenyl and benzoate degradation. All genes previously identified as being directly involved in biphenyl degradation were up-regulated when cells were grown on biphenyl compared to expression in succinate-grown cells. For benzoate degradation, however, genes for an aerobic coenzyme A activation pathway were up-regulated in biphenyl-grown cells, while the pathway for benzoate degradation via hydroxylation was up-regulated in benzoate-grown cells. The early-stationary-phase biphenyl-grown cells showed similar expression of biphenyl pathway genes, but a surprising up-regulation of C(1) metabolic pathway genes was observed. The microarray results were validated by quantitative reverse transcription PCR with a subset of genes of interest. The XeoChips showed a chip-to-chip variation of 13.9%, compared to the 21.6% variation for spotted oligonucleotide microarrays, which is less variation than that typically reported for PCR product microarrays.


Assuntos
Proteínas de Bactérias/metabolismo , Benzoatos/metabolismo , Burkholderia/metabolismo , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Bifenilos Policlorados/metabolismo , Proteínas de Bactérias/genética , Burkholderia/genética , Burkholderia/crescimento & desenvolvimento , Meios de Cultura , Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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