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1.
Sci Total Environ ; 925: 171761, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38494008

RESUMO

In the framework of the Forum for Air Quality Modelling in Europe (FAIRMODE), a modelling intercomparison exercise for computing NO2 long-term average concentrations in urban districts with a very high spatial resolution was carried out. This exercise was undertaken for a district of Antwerp (Belgium). Air quality data includes data recorded in air quality monitoring stations and 73 passive samplers deployed during one-month period in 2016. The modelling domain was 800 × 800 m2. Nine modelling teams participated in this exercise providing results from fifteen different modelling applications based on different kinds of model approaches (CFD - Computational Fluid Dynamics-, Lagrangian, Gaussian, and Artificial Intelligence). Some approaches consisted of models running the complete one-month period on an hourly basis, but most others used a scenario approach, which relies on simulations of scenarios representative of wind conditions combined with post-processing to retrieve a one-month average of NO2 concentrations. The objective of this study is to evaluate what type of modelling system is better suited to get a good estimate of long-term averages in complex urban districts. This is very important for air quality assessment under the European ambient air quality directives. The time evolution of NO2 hourly concentrations during a day of relative high pollution was rather well estimated by all models. Relative to high resolution spatial distribution of one-month NO2 averaged concentrations, Gaussian models were not able to give detailed information, unless they include building data and street-canyon parameterizations. The models that account for complex urban geometries (i.e. CFD, Lagrangian, and AI models) appear to provide better estimates of the spatial distribution of one-month NO2 averages concentrations in the urban canopy. Approaches based on steady CFD-RANS (Reynolds Averaged Navier Stokes) model simulations of meteorological scenarios seem to provide good results with similar quality to those obtained with an unsteady one-month period CFD-RANS simulations.

2.
J Environ Manage ; 245: 122-130, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150903

RESUMO

This paper presents the first outcomes of the "FAIRMODE pilot" activity, aiming at improving the way in which air quality models are used in the frame of the European "Air Quality Directive". Member States may use modelling, combined with measurements, to "assess" current levels of air quality and estimate future air quality under different scenarios. In case of current and potential exceedances of the Directive limit values, it is also requested that they "plan" and implement emission reductions measures to avoid future exceedances. In both "assessment" and "planning", air quality models can and should be used; but to do so, the used modelling chain has to be fit-for-purpose and properly checked and verified. FAIRMODE has developed in the recent years a suite of methodologies and tools to check if emission inventories, model performance, source apportionment techniques and planning activities are fit-for-purpose. Within the "FAIRMODE pilot", these tools are used and tested by regional/local authorities, with the two-fold objective of improving management practices at regional/local scale, and providing valuable feedback to the FAIRMODE community. Results and lessons learnt from this activity are presented in this paper, as a showcase that can potentially benefit other authorities in charge of air quality assessment and planning.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental
3.
Oncogene ; 26(27): 3952-62, 2007 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-17213814

RESUMO

Fenretinide (4-HPR) is a synthetic retinoid with antitumor activity, which induces apoptosis in cancer cell lines of different histotypes. To identify genes contributing to its apoptotic activity in ovarian cancer cells, we monitored, by cDNA arrays, gene expression changes after 4-HPR exposure in A2780, a human ovarian carcinoma cell line sensitive to the retinoid. Among the differentially expressed transcripts, PLAcental Bone morphogenetic protein (PLAB), a proapoptotic gene, was the most highly induced. In a panel of ovarian carcinoma cell lines with different 4-HPR sensitivities, PLAB upregulation was associated with cellular response to 4-HPR, its overexpression increased basal apoptosis and its silencing by small interfering RNA decreased the ability of 4-HPR to induce apoptosis. PLAB induction by 4-HPR was p53- and EGR-1 independent and was regulated, at least in part, by increased stability of PLAB mRNA. PLAB up-modulation by 4-HPR also occurred in vivo: in ascitic cells collected from patients with ovarian cancer before and after 4-HPR treatment, PLAB was upmodulated in 2/4 patients. Our results in certain ovarian cancer cell lines indicate a role for PLAB as a mediator of 4-HPR-induced apoptosis. The correlation of increased PLAB in vivo with antitumor activity remains to be established.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Morfogenéticas Ósseas/genética , Fenretinida/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Ovarianas/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Western Blotting , Proteínas Morfogenéticas Ósseas/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Fenretinida/uso terapêutico , Perfilação da Expressão Gênica , Fator 15 de Diferenciação de Crescimento , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Retinoides/química , Retinoides/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
4.
Cell Death Differ ; 11(3): 270-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14647238

RESUMO

Fenretinide (HPR), a synthetic retinoid that exhibits lower toxicity than other retinoids, has shown preventive and therapeutic activity against ovarian tumors. Although the growth inhibitory effects of HPR have been ascribed to its ability to induce apoptosis, little is known about the molecular mechanisms involved. Since the proto-oncogene c-Fos has been implicated in apoptosis induction, we analyzed its role in mediating HPR response in a human ovarian carcinoma cell line (A2780) sensitive to HPR apoptotic effect. In these cells, HPR treatment caused induction of c-Fos expression, whereas such an effect was not observed in cells made resistant to HPR-induced apoptosis (A2780/HPR). Moreover, in a panel of other human ovarian carcinoma cell lines, c-Fos inducibility and HPR sensitivity were closely associated. Ceramide, which is involved in HPR-induced apoptosis, was also involved in c-Fos induction because its upregulation by HPR was reduced by fumonisin B(1), a ceramide synthase inhibitor. The causal relationship between c-Fos induction and apoptosis was established by the finding of an increased apoptotic rate in cells overexpressing c-Fos. Similarly to that observed for c-Fos expression, HPR treatment increased c-Jun expression in HPR-sensitive but not in HPR-resistant cells, suggesting the involvement of the transcription factor activating protein 1 (AP-1) in HPR-induced apoptosis. In gene reporter experiments, HPR stimulated AP-1 transcriptional activity and potentiated the AP-1 activity induced by 12-tetradecanoylphorbol 13-acetate. Furthermore, inhibition of AP-1 DNA binding, by transfecting A2780 cells with a dominant-negative Fos gene, caused decreased sensitivity to HPR apoptotic effects. Overall, the results indicate that c-Fos plays a role in mediating HPR-induced growth inhibition and apoptosis in ovarian cancer cells and suggest that c-Fos regulates these processes as a member of the AP-1 transcription factor.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma/tratamento farmacológico , Fenretinida/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-fos/metabolismo , Antineoplásicos/toxicidade , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/patologia , Linhagem Celular Tumoral , Ceramidas/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Fenretinida/toxicidade , Fumonisinas/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Genes jun/efeitos dos fármacos , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Proto-Oncogene Mas , Fator de Transcrição AP-1/metabolismo , Regulação para Cima
5.
Naturwissenschaften ; 90(11): 517-20, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14610650

RESUMO

The female-produced sex pheromone of Phyllophaga crinita (Burmeister) (Coleoptera: Scarabaeidae: Melolonthinae; the adult has no common name) is identified as methyl 2-(methylthio)benzoate. This is the first identification of a sulfur-containing, long-distance, female-produced sex attractant from any insect taxa. The root-feeding larvae of this species are serious pests in many crops in Texas and Mexico. In field tests, many P. crinita males were captured in traps baited with the authentic compound. Interestingly, a heteroatom analog, methyl 2-methoxybenzoate, also captured P. crinita males, but only at a dose 10,000 times higher than the lowest tested dose of the authentic pheromone.


Assuntos
Benzoatos/química , Besouros/fisiologia , Feromônios/química , Comportamento Sexual Animal , Sulfetos/química , Animais , Cromatografia Gasosa , Besouros/crescimento & desenvolvimento , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Larva , Masculino , Enxofre/análise
6.
Exp Appl Acarol ; 24(2): 85-113, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11108390

RESUMO

Bulb mites of the genus Rhizoglyphus (Claparède) (Acari: Acaridae) have been identified as pests of many crops and ornamentals in storage, in the greenhouse, and in the field. The most important hosts are species in the family Liliaceae (e.g. Allium spp.), but bulb mites will often attack other important crops such as potatoes (Solanum sp.) and carrots (Daucus carota). Despite their economic importance and broad distribution, the systematics of the genus remains in a state of confusion and is in need of a comprehensive revision. In addition, the field biology and ecology of these mites is not well understood, and methods for sampling, monitoring, and loss assessment are limited. Management of bulb mites is complicated by their short generation time, high reproductive potential, broad food niche, interactions with other pests and pathogens, and unique adaptations for dispersal. Historically, control of these acarine pests has relied on the use of synthetic miticides and insecticides, but this option is now limited due to documented resistance and withdrawal of registration of some products. Alternative control strategies, including cultural and biological control, have shown limited success, but need to be further developed and implemented.


Assuntos
Produtos Agrícolas/parasitologia , Liliaceae/parasitologia , Ácaros/fisiologia , Controle Biológico de Vetores , Animais , Ácaros/classificação , Ácaros/crescimento & desenvolvimento
7.
Mech Dev ; 88(1): 123-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10525197

RESUMO

We report the cloning and expression pattern of Ci-msxb the second Ciona intestinalis homeobox gene homologue to the Drosophila muscle segment homeobox (msh) gene. Northern blot analysis showed that transcripts appeared at gastrula stage, peaked in the early tailbud and decreased during the tailed stages. Whole mount in situ hybridization showed that the Ci-msxb expression first is detected at 110 cell-stage in the blastomeres that are precursors of different tissue (muscle, spinal cord, endodermal strand, brain, mesenchyme, pigmented cells and primordial pharynx). Transcript level declined in mesoderm cells after the completion of gastrulation, but mRNAs were still present in the folding neural plate during neurulation and in the pigmented cells. Later, at larval stage, transcripts were present around the otolith and ocellus, in a restricted part of the nervous system and in the primordial pharynx; the gene expression was conserved after metamorphosis in the juvenile.


Assuntos
Ciona intestinalis/crescimento & desenvolvimento , Ciona intestinalis/genética , Proteínas de Drosophila , Animais , Blastômeros , Ciona intestinalis/embriologia , Drosophila/genética , Ectoderma , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Larva , Dados de Sequência Molecular , Sistema Nervoso/embriologia , Sistema Nervoso/crescimento & desenvolvimento , Homologia de Sequência de Aminoácidos
8.
Annu Rev Entomol ; 44: 233-56, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-15012373

RESUMO

For those arthropod species adapted for living below the soil surface, the soil is a refuge from the biotic and abiotic perturbations existing above ground. Convergent morphological, physiological, and behavioral adaptations of epedaphic, euedaphic, and hemiedaphic arthropods to selective aspects of subterranean existence are examined in light of overlapping ecological niches. The abiotic impact of the soil environment and its relationship to arthropod evolution, radiation, and ecology are discussed as well. Specific areas addressed include the invasion of land by marine arthropods, the impact of morphology on arthropod mobility, osmoregulatory/respiratory systems, and defensive strategies.

9.
Dev Growth Differ ; 40(4): 387-94, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9727352

RESUMO

A full-length cDNA encoding a highly conserved calmodulin was isolated from a cDNA library prepared from hatched larvae of the ascidian Ciona intestinalis. Sequence analysis has identified a 447 b.p. open reading frame, encoding a putative protein of 149 amino acid residues, with a predicted molecular weight of 16.8 kDa, showing 85-98% identity to known calmodulins. Northern blot analysis revealed a single transcript of about 0.8 kb in length, which was maternally expressed and progressively increased during development, until late tail-bud stage. Whole-mount in situ hybridizations, carried out on embryos at different stages of development, showed that starting from the neurula stage, the C. intestinalis calmodulin (Ci-CaM) expression became restricted to the neuroectoderm and that in larvae it was specifically detected in the nervous system.


Assuntos
Calmodulina/genética , Ciona intestinalis/química , Regulação da Expressão Gênica no Desenvolvimento/genética , Especificidade de Órgãos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Biomarcadores/análise , Calmodulina/análise , Ciona intestinalis/embriologia , Ciona intestinalis/fisiologia , DNA/isolamento & purificação , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Dados de Sequência Molecular , Especificidade de Órgãos/fisiologia , Filogenia , RNA Mensageiro/análise , Análise de Sequência de DNA , Urocordados/química
10.
J Chem Ecol ; 20(9): 2415-27, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24242814

RESUMO

Females of the Oriental beetle,Anomala orientalis (Waterhouse), release a sex pheromone composed of a 9:1 blend of (Z)- and (E)-7-tetradecen-2-one. The double-bond position of the pheromone was determined by DMDS derivatization and interpretation of the fragmentation patterns produced by monounsaturated ketones. In a sustained-flight tunnel, males responded by flying toward female beetles and attempting to copulate with them. Both effluvium and whole-body extracts of OB females were analyzed, and the activity was found only in the airborne extracts. Flight-tunnel bioassays also showed that a synthetic 90:10Z/E blend on a rubber septum was attractive and that the responses of males to this blend were equivalent toZ isomer alone, but much better than to the singleE isomer.

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