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1.
Mar Pollut Bull ; 50(11): 1328-34, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15949821

RESUMO

We assessed the capacity for heavy metals accumulation in Talorchestia ugolinii by standard methods of heavy metals analysis. To compare the bioaccumulation in syntopic sandhopper species, we collected samples of T. ugolinii and Talitrus saltator living on the same and on different beaches in Corsica. There was a marked difference in the zonal distribution of the two species along the sea-land axis of the beach: T. ugolinii was distributed nearer the water line than T. saltator. The bioaccumulation capacity of T. ugolinii only partly matched that of the Mediterranean T. saltator: while Hg, Zn, Cu, and Cd were accumulated by both species, Al and Fe were accumulated by T. saltator but not by T. ugolinii. Pb was accumulated only by T. ugolinii, while Cr did not seem to be accumulated by either species. The bioaccumulation in sympatric T. saltator and T. ugolinii specimens collected on the same beach reflected the general trend of the two species on the Tyrrhenian and Corsican coasts, respectively. Moreover, six of the eight heavy metals considered (Hg, Pb, Zn, Fe, Al, Cu) were present in higher quantities in T. ugolinii than in T. saltator, independently of whether the trace elements were accumulated by the two species. Thus, there are some differences between T. ugolinii and T. saltator, even when the two species live in the same locality. These differences involve their zonation within the damp belt of sand, the bioaccumulation of some heavy metals (Al, Pb, Fe), and the quantity of each heavy metal in the body, independent of the bioaccumulation capacity.


Assuntos
Anfípodes/metabolismo , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Metais Pesados/farmacocinética , Animais , França , Geografia , Metais Pesados/análise , Especificidade da Espécie , Espectrofotometria Atômica
2.
J Environ Monit ; 6(11): 919-25, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15536507

RESUMO

The uptake rates of selected hydrophobic organic contaminants (HOCs) by semipermeable membrane devices (SPMDs)--a polyethylene layflat containing the lipid triolein--were investigated under natural conditions. SPMDs were exposed in three sampling sites (industrial, urban, and agricultural areas) in the Tajo River (Toledo, Spain) for 5, 11 and 20 d. The organochlorine compounds 4,4'-DDT, 4,4'-DDE, alpha-HCH, gamma-HCH, pentachlorobenzene, hexachlorobenzene, and polychlorinated biphenyls (PCBs), and the 16 priority pollutant polycyclic aromatic hydrocarbons (PAHs) were detected in the SPMDs deployed in the three sampling sites. A linear uptake rate was found for DDTs and for 4-Cl- and 5-Cl-substituted PCB congeners in all sampling sites. Concentrations of HCHs (80.3 ng g(-1) SPMD for alpha-HCH and 109 ng g(-1) SPMD for gamma-HCH after 20 d of exposure) increased according to a linear uptake rate in the SPMDs deployed in the sampling site located in the agricultural area. Likewise, a marked increase of total PAH concentration (up to 300 ng g(-1) SPMD after 20 d of exposure) was solely found in the sampling site situated near a thermoelectric power station. Examination of individual PAHs revealed that PAHs with log K(OW) between 4.2 and 5.7 displayed a linear uptake rate over the 20 d of exposure. Water concentrations (ng L(-1)) of HCB (0.80-2.48), lindane (1.30-11.5), 4,4'-DDT (0.61-2.02), 4,4'-DDE (6.89-11.6) and total PAHs (12.0-26.7) estimated by a linear uptake kinetic model were found to be high in comparison with other polluted aquatic systems, and similar to concentrations in other Spanish rivers. Our results suggest that SPMD kinetic uptake studies in the natural environment are recommended for identifying point-pollution sources, and that shorter times of SPMD exposure (approximately 1 week) are desirable to minimize one of the main problems of field SPMD deployment, i.e., the biofouling, which negatively affects the estimation of the dissolved HOC concentrations.


Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Membranas Artificiais , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Poluentes Químicos da Água/análise , Agricultura , Monitoramento Ambiental/instrumentação , Hidrocarbonetos Clorados/química , Interações Hidrofóbicas e Hidrofílicas , Indústrias , Hidrocarbonetos Policíclicos Aromáticos/química , Espanha
5.
Mar Pollut Bull ; 48(5-6): 526-32, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14980468

RESUMO

The use of sandhoppers and beachfleas as biomonitors of heavy metals contamination is relatively recent. Using adult individuals of Talitrus saltator from nine localities on the northern Mediterranean Sea, we studied the concentrations of eight trace elements: Al, Cd, Cr, Fe, Hg, Pb, Cu, Zn, both in the substratum and in the individuals. We also carried out a preliminary investigation of the correspondence between the sandhoppers' genetic variability and heavy metal contamination at the sampling sites. T. saltator accumulated Cd, Cu, Zn and Hg (at higher concentrations than in the sand) and also Al and Fe (at lower concentrations than in the sand). It seems that Mediterranean sandhoppers do not accumulate Pb and Cr. An intraspecific comparison between northern European (Baltic) and Mediterranean populations of T. saltator was made. Finally, we observed a tendency to a positive correlation between the sandhoppers' genetic variability and heavy metals contamination.


Assuntos
Anfípodes/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Anfípodes/genética , Animais , Variação Genética , Genética Populacional , Mar Mediterrâneo , Metais Pesados/farmacocinética , Distribuição Tecidual
6.
Homeopathy ; 92(4): 195-202, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14587686

RESUMO

CONTEXT: This research aimed at verifying the efficacy of homeopathic treatments by plant-based bioassays, which may be suitable for basic research, because they lack placebo effects and provide large datasets for statistical analyses. OBJECTIVE: To evaluate the effects of homeopathic treatments of arsenic trioxide (As2O3) on tobacco plants subjected to tobacco mosaic virus (TMV) inoculation as biotic stress. DESIGN: Blind, randomized experiment using tobacco leaf disks. MATERIALS AND METHODS: Tobacco plants (Nicotiana tabacum L. cultivar Samsun) carrying the TMV resistance gene N. TMV inoculated leaf disks were floated for 3 days in the following: Distilled water (control). H2O 5 and 45 decimal and centesimal potencies. As2O3 5 and 45 decimal and centesimal potencies. The main outcome measures is the number of hypersensitive lesions observed in a leaf disk. RESULTS: Homeopathic treatments of arsenic induce two effects on the plant: (i) increased resistance to TMV; (ii) decrease variability between experiments (system variability). CONCLUSIONS: In this experimental model two actions of homeopathic treatment were detected: decrease in system variability and enhancement of the natural tendency of the system towards an 'equilibrium point'.


Assuntos
Antivirais/farmacologia , Arsenicais/farmacologia , Imunidade Inata , Óxidos/farmacologia , Doenças das Plantas/virologia , Folhas de Planta/imunologia , Vírus do Mosaico do Tabaco/imunologia , Tabaco/virologia , Trióxido de Arsênio , Bioensaio , Homeopatia/métodos , Folhas de Planta/virologia , Projetos de Pesquisa , Fatores de Tempo , Vírus do Mosaico do Tabaco/metabolismo
7.
Homeopathy (Londres.2002) ; 92(4): 195-202, 2004. tab
Artigo em Inglês | HomeoIndex - Homeopatia | ID: hom-7489

RESUMO

This research aimed at verifying the efficacy of homeopathic treatments by plant-based bioassays, which may be suitable for basic research, because they lack placebo effects and provide large datasets for statistical analyses. (AU)


Assuntos
Arsenicum Album/uso terapêutico , Vírus do Mosaico do Tabaco , Agronomia
9.
Environ Pollut ; 121(3): 349-61, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12685764

RESUMO

The paper reports a case of evident and widespread leaf damage on trees in southern Tuscany (Central Italy) attributed to the input of pollutants produced in a geothermal area. The main potentially phytotoxic substances are boron and hydrogen sulphide. Trees affected are conifers as well as both evergreen and deciduous broadleaves. In the present study the possible impact of geothermal pollutants on Quercus pubescens leaves has been considered. Leaf samples coming from three sampling locations (S1 inside the geothermal area; S2 on the margins; S3 outside) and three consecutive dates (June, July and August) were analyzed for the following parameters: sulphur and boron concentration; leaf area; leaf mass per area; chlorophyll fluorescence (Fv/Fm); chlorophyll a, chlorophyll b and carotenoid concentrations. Anatomical and ultrastructural observations were also performed. In all sampling location sulphur and boron concentrations are greater than the background values recorded in southern Tuscany in a previous survey. The sulphur concentration in leaves was higher in S1 than S2 and S3, but did not increase throughout the survey period. Boron reached the greatest concentrations in S2 and showed a continuous increase over the study period. Leaves subjected to a higher load of pollutants were smaller in size (in terms of leaf area), but were more sclerophyllous. Damaged chloroplasts and reduced Fv/Fm values were observed at S1 and S2, but chlorophyll concentration values were higher at S1. Such an apparent anomaly can possibly be explained by the onset of compensation and recovery mechanisms. Foliar injuries appeared to be related to boron concentration.


Assuntos
Boro/toxicidade , Poluição Ambiental , Folhas de Planta/efeitos dos fármacos , Centrais Elétricas , Quercus , Fenômenos Geológicos , Geologia , Temperatura Alta , Enxofre/toxicidade
10.
Environ Pollut ; 116(2): 279-87, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11806456

RESUMO

Samples of the moss Hypnum cupressiforme and the epiphytic lichen Parmelia, caperata were collected during the summer of 1999 in an area (Colline Metallifere, central Italy) intensively exploited in the past for metals (Cu, Fe, Pb, Zn) and currently for geothermal resources. Lichens were more sensitive than mosses to emissions of S compounds near geothermal fields and abandoned sulphide ore smelting plants. Comparison of elemental compositions of the two cryptogamic species from the same sampling sites showed significantly higher concentrations of lithophile elements (Al, Cr, Fe, Mn, Ni, Ti) in the moss and atmophile elements (Hg, Cd. Pb, Cu, V, Zn) in the lichen. Patterns of bioaccumulation of elements throughout the study area were quite similar for widespread pollutants such as S, B, As, Zn, Cr and Ni, but the lichen and the moss showed different distribution patterns of Hg, Cd and other elements subject to long-range atmospheric transport. These results are due to differences in the morphology and ecophysiology of mosses and lichens and indicate that these organisms cannot be used interchangeably as biomonitors of metals in areas with mineral deposits.


Assuntos
Bryopsida , Monitoramento Ambiental/métodos , Líquens , Metais Pesados/farmacocinética , Mineração , Oligoelementos/farmacocinética , Poluentes Ambientais/análise , Poluentes Ambientais/farmacocinética , Itália , Metais Pesados/análise , Distribuição Tecidual , Oligoelementos/análise
11.
Mar Pollut Bull ; 42(12): 1390-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11827127

RESUMO

The cardiac activity of three limpets (Patella rustica, P. caerulea and P. aspera), having a different vertical zonation on the Mediterranean rocky shores, was monitored using a non-invasive technique, during 6 h exposure to copper solutions (0.1 and 0.5 ppm), and after return to copper-free conditions. At 0.1 ppm no significant variation of heart rate was observed in the three species with respect to control conditions, while after 3 h at 0.5 ppm a consistent bradycardia was evident in P. caerulea and P. aspera, but not in P. rustica. After 6 h at 0.5 ppm most of the specimens of the three species were acardic but still reactive to mechanical stimulation. Tests on the resumption of cardiac activity after 6 h exposure to 0.5 ppm showed that even after a prolonged cessation of cardiac activity, limpets quickly resumed heartbeating once returned to clean seawater. However, recovery of heart-beating was faster in the mid- and high-shore species (P. caerulea and P. rustica, respectively) than in the lower-shore P. aspera. Moreover, the cardiac pattern upon recovery was definitely bradycardic in P. aspera, while the other two species showed a significant overshooting in heartbeating rate. Measurement of body burdens of copper showed that P. rustica and P. caerulea were faster in removing the excess of copper than the lower-shore P. aspera. In conclusion, this study showed that taxonomically close and syntopic species having a different zonal distribution exhibit different cardiac responses to water-borne copper and stresses the importance of comparative studies on physiological responses of organisms to metal pollution.


Assuntos
Cobre/toxicidade , Moluscos/fisiologia , Animais , Relação Dose-Resposta a Droga , Exposição Ambiental , Frequência Cardíaca/efeitos dos fármacos , Cinética , Especificidade da Espécie
13.
Am J Dermatopathol ; 21(1): 42-5, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10027526

RESUMO

Reactive cutaneous angioendotheliomatosis (RCA) is an uncommon benign disease characterized by intravascular proliferation of endothelial cells. The observation of RCA in infants is exceedingly rare. We describe a case of RCA in a 3-month-old infant. The lesions were characterized by six small purpuric papules (1-2 mm in diameter), distributed on the thighs and neck. The general condition of the patient was good, with no lymphadenopathy, systemic involvement, or fever. The histopathologic features of a papule were characterized by the presence of cohesive aggregates of large mononucleated cells protruding into the lumina of dilated vessels and filling some of them completely. Neither an inflammatory infiltrate nor a proliferation of pericytes were present around blood vessels. Intravascular proliferating cells demonstrated positive staining for Ulex europaeus agglutinin 1 (UEA-1) and for Factor VIII-RA and CD34 antigens. The course of the disease was unremarkable with persistence of the lesions for 8 months; no treatment was started.


Assuntos
Linfoma não Hodgkin/patologia , Lectinas de Plantas , Neoplasias Cutâneas/patologia , Antígenos CD34/análise , Feminino , Humanos , Imuno-Histoquímica , Lactente , Lectinas/análise , Linfoma não Hodgkin/metabolismo , Pele/química , Pele/patologia , Neoplasias Cutâneas/metabolismo , Fator de von Willebrand/análise
15.
Dermatology ; 185(2): 123-7, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1421624

RESUMO

HLA polymorphisms of class I (HLA-A, B, C) of class II (HLA-DR, DQ) and of class III (C4A, C4B, BF) were investigated in 93 Northern Italian patients affected with vitiligo and in 388 controls. Vitiligo patients had significant increases in HLA-A30 (corrected p, pc = 0.0144), Cw6 (pc = 0.0189), DQw3 (pc less than 0.0003) and a significant decrease in C4AQ0 (pc = 0.003). Nonfamilial vitiligo is marked by increases in HLA-A30 and DQw3. Extensive vitiligo is marked by increases in HLA-A30 and Cw6. These findings suggest that immunogenetic mechanisms may be responsible for vitiligo and that unique HLA phenotypes may influence the expression of vitiligo in this population.


Assuntos
Antígenos HLA-A/sangue , Antígenos HLA-C/sangue , Antígenos HLA-DQ/sangue , Vitiligo/imunologia , Adolescente , Adulto , Idoso , Criança , Eletroforese , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo Genético/imunologia , Vitiligo/genética
17.
Ital J Biochem ; 31(2): 127-38, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7129855

RESUMO

The release of purine compounds from the perfused rat heart under basal conditions was determined by high pressure liquid chromatography. Uric acid resulted the major degradative released into the perfusate. Lower levels of hypoxanthine, xanthine and inosine were found. The uric acid concentration showing that the rat heart is able to catabolize the purine compounds up to uric acid. No leakage of catabolic enzymes was observed and thereby the breakdown of the released nucleosides and bases proved to be intracellular. This heart ability was confirmed by the analysis of the degradation products of AMP added to the perfusion medium in the recirculating system. AMP was sequentially broken down to adenosine, then to inosine, hypoxanthine and xanthine and finally to uric acid that as end product accumulated in the perfusate.


Assuntos
Miocárdio/metabolismo , Ácido Úrico/metabolismo , Monofosfato de Adenosina/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Hipoxantinas/metabolismo , Inosina/metabolismo , Masculino , Perfusão , Ratos , Ratos Endogâmicos , Xantinas/metabolismo
18.
Boll Ist Sieroter Milan ; 57(5): 671-5, 1978 Nov 30.
Artigo em Italiano | MEDLINE | ID: mdl-114199

RESUMO

The circulating lymphocytes of 16 normal subjects and of 18 patients with paraproteinemia have been characterized by measuring the levels of ADA, AMPA, PNPase, CDA. The results obtained reveal a highly significant increase in PNPase of subjects affected by paraproteinemia as compared to that of normal subjects (p less than 0.005). The fact that the increased enzymatic levels are found mainly in patients not affected by Bence-Jones proteinuria seems to indicate that the evolution of the paraproteinemia disease is in some way related to the intralymphocyte levels of PNPase.


Assuntos
AMP Desaminase/sangue , Adenosina Desaminase/sangue , Citidina Desaminase/sangue , Linfócitos/enzimologia , Nucleosídeo Desaminases/sangue , Nucleotídeo Desaminases/sangue , Paraproteinemias/enzimologia , Pentosiltransferases/sangue , Purina-Núcleosídeo Fosforilase/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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