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1.
Phys Rev Lett ; 131(17): 171901, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37955487

RESUMO

The first observation and study of two new baryonic structures in the final state Ξ_{b}^{0}π^{+}π^{-} and the confirmation of the Ξ_{b}(6100)^{-} state in the Ξ_{b}^{-}π^{+}π^{-} decay mode are reported using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb^{-1}. In addition, the properties of the known Ξ_{b}^{*0}, Ξ_{b}^{'-} and Ξ_{b}^{*-} resonances are measured with improved precision. The new decay mode of the Ξ_{b}^{0} baryon to the Ξ_{c}^{+} π^{-} π^{+} π^{-} final state is observed and exploited for the first time in these measurements.

2.
Environ Geochem Health ; 36(2): 209-23, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23990124

RESUMO

In order to study the pollution of an aquatic ecosystem, it is necessary to analyze not only the levels of chemical pollutants in water, but also those accumulated in the sediment matrix, as well as to assess its ecotoxicological status. The Alqueva reservoir, the largest artificial lake in Europe, was chosen as case study as it constitutes the most important water supply source in southern Portugal. It is located in the Guadiana River Basin, in a semi-arid region with high levels of water scarcity and where agriculture is one of the main activities. The evaluation of sediments comprised: (1) physical and chemical analysis (grain size, pH, organic matter, nitrogen, phosphorus); (2) potentially toxic trace elements (Cu, As, Pb, Cr, Cd, Zn and Ni); and (3) ecotoxicological evaluation with Vibrio fischeri, Thamnocephalus platyurus, Daphnia magna, and Heterocypris incongruens. Total trace element concentrations indicated that As, Cd, and Pb surpassed the Canadian levels for the protection of aquatic life, in most of Alqueva's sites. The results of the toxicity assessment showed that some locations induced acute and chronic toxicity in the species used. Further, the H. incongruens was the most sensitive species as far as the contamination found in the sediment is concerned, followed by the bacteria V. fischeri. This integrative approach, together with the water column quality assessment, allowed a comprehensive evaluation of the environmental quality of this strongly modified water body and will allow the implementation of remediation strategies to obtain a good ecological potential as proposed in the Water Framework Directive.


Assuntos
Ecotoxicologia/métodos , Água Doce , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Aliivibrio fischeri/efeitos dos fármacos , Animais , Crustáceos/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Monitoramento Ambiental/métodos , Concentração de Íons de Hidrogênio , Metais/análise , Nitrogênio/análise , Fósforo/análise , Portugal , Testes de Toxicidade Crônica
3.
Ecotoxicol Environ Saf ; 72(2): 344-50, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18547642

RESUMO

Endosulfan sulphate is the transformation product of endosulfan and it is the most frequent form of surface water contamination with endosulfan. The aim of this study was to evaluate the possible effects promoted by endosulfan sulphate in changes on the life cycle, embryo development and sex differentiation of Daphnia magna. The endpoints used were moulting frequency, fecundity, growth, developmentally abnormalities and sexual differentiation. The nominal concentrations of endosulfan sulphate tested ranged from 9.2 to 458.7 microg L(-1). Endosulfan sulphate promoted a significant decrease of the offspring number in all concentrations. Results showed a reduction of the size of females, together with a decrease in moulting frequency. Furthermore, an increase in embryo deformities was observed at all concentrations tested. Above a concentration of 91.7 microg L(-1) there was an increased production of males. The results suggest that endosulfan sulphate interferes with the life cycle and sex determination of the crustacean D. magna.


Assuntos
Daphnia/efeitos dos fármacos , Daphnia/fisiologia , Desenvolvimento Embrionário/efeitos dos fármacos , Endossulfano/toxicidade , Inseticidas/toxicidade , Diferenciação Sexual/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Daphnia/embriologia , Daphnia/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário/fisiologia , Feminino , Masculino , Reprodução/efeitos dos fármacos , Reprodução/fisiologia , Diferenciação Sexual/fisiologia , Razão de Masculinidade , Testes de Toxicidade Crônica
4.
Ecotoxicol Environ Saf ; 72(6): 1714-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19482356

RESUMO

Chlorpyrifos is a non-systemic organophosphorus insecticide leading to the inhibition of the enzyme cholinesterase. Nowadays, this insecticide is widely used on a variety of crops and is frequently detected in surface waters around the world. The main aims of this study were to evaluate the effects of this insecticide on the embryonic development of Daphnia magna, and to assess the sensitivity of this endpoint in comparison with the endpoint of the chronic 21-day test. The featured endpoints were the number of offspring per female and abnormalities of both offspring and embryos. Chlorpyrifos exhibited significant toxic effects on the embryonic development manifested in the appearance of abnormalities, including arrested eggs, in 20% of the embryos exposed to a concentration of 0.01 microgL(-1). Furthermore, chronic exposition to the insecticide yielded a proportion of offspring abnormalities in later stages of development of about 43% at 0.01 microgL(-1). In contrast, a significant reduction in the number of offspring produced per female was only observed above a concentration of 0.03 microgL(-1). Hence, these results suggest that developmental abnormality was a more sensitive endpoint than the number of offspring production per female.


Assuntos
Clorpirifos/toxicidade , Daphnia/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Inseticidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Daphnia/embriologia , Embrião não Mamífero/anormalidades , Embrião não Mamífero/efeitos dos fármacos , Feminino , Exposição Materna
5.
Semergen ; 42(6): 380-7, 2016 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-26364135

RESUMO

OBJECTIVE: The aim of this work is to study the survival of lung cancer patients treated at a referral hospital in Zaragoza (Spain). MATERIAL AND METHOD: The Kaplan-Meier test was used to calculate observed survival. The automatic calculation of the Catalan Institute of Oncology was used to analyse relative survival. RESULTS: Mean survival time was 25.74 months. There was no difference when comparing age groups (P=.151), gender (P=.369), and histological type of tumour (P=.086). Survival by stage of the disease at diagnosis revealed statistically significant differences (P<.001). Relative survival 5 years after diagnosis for the group analysed was 14%. Survival was higher for men (15.5%), in patients under 60 (16.7%) and squamous tumours (18.7%). CONCLUSIONS: Survival by tumour stage was in line with the TNM Staging System for Lung Cancer. These results suggest that overall survival rate for lung cancer in Zaragoza remains very low in the long term, and this depends on the stage of the disease at diagnosis.


Assuntos
Carcinoma/mortalidade , Neoplasias Pulmonares/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Fatores Sexuais , Espanha/epidemiologia , Taxa de Sobrevida , Centros de Atenção Terciária
6.
Vet Immunol Immunopathol ; 60(3-4): 291-303, 1998 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-9589568

RESUMO

Based on an analysis of their reactivity with porcine peripheral blood lymphocytes (PBL), only three of the 57 mAbs assigned to the T cell/activation marker group were grouped into cluster T9 along with the two wCD8 workshop standard mAbs 76-2-11 (CD8a) and 11/295/33 (CD8b). Their placement was verified through the use of two-color cytofluorometry which established that all three mAbs (STH101, #090; UCP1H12-2, #139; and PG164A, #051) bind exclusively to CD8+ cells. Moreover, like the CD8 standard mAbs, these three mAbs reacted with two proteins with a MW of 33 and 35 kDa from lymphocyte lysates and were, thus, given the wCD8 designation. Because the mAb STH101 inhibited the binding of mAb 76-2-11 but not of 11/295/33, it was given the wCD8a designation. The reactivity of the other two new mAbs in the T9 cluster with the various subsets of CD8+ lymphocytes were distinct from that of the other members in this cluster including the standards. Although the characteristic porcine CD8 staining pattern consisting of CD8low and CD8high cells was obtained with the mAb UCP1H12-2, a wider gap between the fluorescence intensity of the CD8low and CD8high lymphocytes was observed. In contrast, the mAb PG164A, not only exclusively reacted with CD4-/CD8high lymphocytes, but it also failed to recognize CD4/CD8 double positive lymphocytes. It was concluded that this mAb is specific for a previously unrecognized CD8 epitope, and was, thus, given the wCD8c designation. A very similar reactivity pattern to that of PG164A was observed for two other mAbs (STH106, #094; and SwNL554.1, #009). Although these two mAbs were not originally positioned in the T cell subgroup because of their reactivity and their ability to inhibit the binding of PG164A, they were given the wCD8c designation. Overall, five new wCD8 mAbs were identified. Although the molecular basis for the differences in PBL recognition by these mAbs is not yet understood, they will be important in defining the role of CD8+ lymphocyte subsets in health and disease.


Assuntos
Anticorpos Monoclonais/análise , Antígenos CD8/imunologia , Suínos/imunologia , Animais , Especificidade de Anticorpos , Reações Antígeno-Anticorpo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD8/biossíntese
7.
Vet Immunol Immunopathol ; 60(3-4): 251-60, 1998 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-9589563

RESUMO

After initial evaluation of the 176 new and 19 control monoclonal antibodies (mAb) submitted to the Second International Swine CD Workshop, 57 were assigned to the T-cell/activation marker subgroup. These 57 mAb were further analyzed using flow cytometry on whole blood lymphocytes, splenocytes, Peyer's patch lymphocytes, in vitro cell lines, broncho-alveolar lavage cells, Con A and PHA blasts, fetal cell populations, and by 2-color flow cytometry against mAb to porcine CD2, CD4, and CD8. Finally, the molecular weights of the target antigens were characterized when possible. As a result of these analyses, 23 mAb were distributed into 7 CD clusters. Newly confirmed mAb assignments included: two CD2; one CD4; two CD5; one wCD6; and one wCD25. Three new mAb were found that reacted with wCD8, one of which defined a new epitope, wCD8c. For the first time, mAb against porcine CD3 were identified, including 6 mAb that reacted with three different epitopes. Several new mAb reacted with antigens whose expression varied depending on the activation state of the test cell. These will require further characterization in order to assign a CD number.


Assuntos
Anticorpos Monoclonais/metabolismo , Antígenos CD/imunologia , Ativação Linfocitária , Suínos/imunologia , Linfócitos T/imunologia , Animais , Reações Antígeno-Anticorpo , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos CD2/imunologia , Complexo CD3/imunologia , Antígenos CD4/imunologia , Antígenos CD5/imunologia , Antígenos CD8/imunologia , Receptores de Interleucina-2/imunologia
8.
Sci Total Environ ; 470-471: 780-90, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24184750

RESUMO

The purpose of this work was to evaluate the dynamic of the water quality from the Alqueva reservoir (Guadiana River Basin, Portugal) and identify the most important parameters that influence its ecological and chemical status. The results could indicate preventive and/or remediation actions that are necessary to improve its quality and status. Water and sediment samples were collected between 2011 and 2012, at five sampling stations, and analyzed for: (i) water - pH, temperature, dissolved oxygen, electrical conductivity, chloride, total phosphorus, total nitrogen, ammonium, nitrate, nitrite, biochemical and chemical oxygen demand, total Fe, Mn, and As; and (ii) sediments - pH, electrical conductivity, organic matter, total nitrogen, total phosphorus, major and trace elements. The results from the water column showed that the organic descriptors exceeded the Portuguese guideline values for water quality for multiple uses at most of the sampling stations. As for nutrients, Ajuda is the station where the concentrations of the total nitrogen and total phosphorus exceeded the guideline values in most months. Ammonium achieved concentrations above the allowed, during the study, in all locations. Trace elements were more abundant in the sediments, surpassing the maximum levels for the protection of aquatic life for As, Cd and Pb, at Alcarrache, Lucefécit and Álamos, respectively. The use of multivariate analysis showed that the major parameters that explained the water quality variability were the nutrients in the water column, and trace elements in the sediments. Comparing the results from this study with results obtained since 2006, we can observe an obvious increment of the organic descriptors and nutrients in the water body. Further, several parameters and observations indicate an increase of the eutrophication process. So, it is urgent to develop preventive actions and remediation processes to stop the degradation so as to improve the quality of the water in this reservoir.


Assuntos
Monitoramento Ambiental , Água Doce/química , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Nitrogênio/análise , Fósforo/análise , Portugal , Análise Espaço-Temporal , Poluição Química da Água/estatística & dados numéricos
9.
Sci Total Environ ; 488-489: 208-19, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24836129

RESUMO

The purpose of this study was to evaluate the potential impact of the pesticides detected in the Alqueva reservoir (Guadiana Basin, South Iberian Peninsula) on the aquatic organisms belonging to this ecosystem. For this purpose, the occurrence and risk assessment of 25 pesticides and of a number of their degradation products were determined in the Alqueva surface waters. The areas (sampling stations) most polluted by pesticides were Sra. Ajuda, Lucefecit and Álamos in the northern and in the middle portions of the reservoir, respectively. The aquatic risk assessment revealed that from the various compounds analysed terbuthylazine, chlorfenvinphos and diazinon presented non-acceptable risk when maximum concentrations were used as the measured environmental concentrations (MEC). The locations that had more samples with risk quotients higher than 1 (high risk) were Sra. Ajuda followed by Lucefécit. The use of risk assessment allowed us to conclude that, despite that the pesticides' concentrations in the water column fulfil the European environmental quality standards, a number of the compounds show a high ecotoxicological risk for the aquatic organisms in the Alqueva ecosystem. The results thereby demonstrate that to have an efficient risk management process, the regulatory authorities of each country must consider an integrative chemical and ecotoxicological approach.


Assuntos
Monitoramento Ambiental , Praguicidas/análise , Poluentes Químicos da Água/análise , Animais , Organismos Aquáticos , Ecossistema , Água Doce/química , Portugal , Medição de Risco
10.
Chemosphere ; 74(5): 676-81, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19042009

RESUMO

The ecdysteroid system is used by crustaceans and other arthropods as the major endocrine signalling molecules, regulating processes such as molting and embryonic development. The aim of this study was to evaluate the ecdysteroid activity of two pesticides (atrazine and endosulfan sulphate), with distinct modes of action and which act in the juvenoid system of the crustacean Daphnia magna as weak juvenoid compounds. To assess the ecdysteroid activity, we first exposed maternal daphnids and embryos to nominal concentrations of the pesticides and determined the effect promoted by these pesticides on the molting frequency and on abnormalities in the embryos development. Furthermore, we evaluated if the toxic effects observed with the isolated pesticides were promoted or not by the disruption of the ecdysteroids system of the crustacean, by co-administrating of them with 20-hydroxyecdysone hormone. This hormone is the prime form of the invertebrate's ecdysteroids system and it is responsible for the crustacean molting process. Both pesticides induced an increase of embryo abnormalities development. Endosulfan sulphate promoted a delay in the molting process. The effects induced by atrazine were not altered by co-exposure to 20-hydroxyecdysone. In contrast, the co-administration of 20-hydroxyecdysone allowed the reversion of the effects on both the molting process and embryonic development elicited by endosulfan sulphate. These results suggest that atrazine promotes its toxicity without interfering with the ecdysteroid activity of the crustacean. On the contrary, endosulfan sulphate is an anti-ecdysteroidal compound for D. magna.


Assuntos
Atrazina/toxicidade , Daphnia/efeitos dos fármacos , Daphnia/crescimento & desenvolvimento , Ecdisteroides/metabolismo , Endossulfano/toxicidade , Herbicidas/toxicidade , Animais , Ecdisterona/farmacologia , Embrião não Mamífero/efeitos dos fármacos , Muda
11.
Chemosphere ; 76(3): 335-40, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19403157

RESUMO

The water flea Daphnia magna belongs to the cyclical parthenogenic species, which can reproduce by either parthenogenesis or sexual reproduction. Recent studies have reported the involvement of the methylfarnesoate hormone, in male sex determination of D. magna. The aim of this study was to evaluate the juvenoid and anti-juvenoid activity of atrazine, endosulfan sulphate, and chlorpyrifos. To assess the juvenoid activity we exposed maternal daphnids to several concentrations of the respective pesticides, using the percentage of male production as endpoint. Fenoxycarb (1microgL(-1)) was used as a positive control. The anti-juvenoid activity was assessed using a similar bioassay after the addition of fenoxycarb (1microgL(-1)) to all test solutions. Fenoxycarb is an insect growth regulator that mimics the action of methylfarnesoate, and promoted the production of 95% of male offspring at the given concentration. Weak juvenoid-agonist activity was detected for endosulfan sulphate, with a significant increase of the percentage of male daphnids detected through logistic regression. In addition, atrazine and endosulfan sulphate antagonized the juvenoid activity of fenoxycarb. These results also corroborate the hypothesis that weak juvenoid agonists can simultaneously act as juvenoid antagonists as it has been observed in other hormonal systems.


Assuntos
Daphnia/efeitos dos fármacos , Disruptores Endócrinos/farmacologia , Hormônios Juvenis/metabolismo , Praguicidas/farmacologia , Poluentes Químicos da Água/farmacologia , Animais , Atrazina/farmacologia , Clorpirifos/farmacologia , Daphnia/embriologia , Daphnia/crescimento & desenvolvimento , Endossulfano/análogos & derivados , Endossulfano/farmacologia , Feminino , Hormônios Juvenis/antagonistas & inibidores , Masculino , Fenilcarbamatos/farmacologia , Reprodução/efeitos dos fármacos , Processos de Determinação Sexual
12.
Environ Int ; 35(3): 545-51, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19010545

RESUMO

Surface waters located in intensive agricultural areas are more vulnerable to the pesticides contamination, which is a major concern if the water is intended to be used for human consumption. The aim of this study was to evaluate the presence and the distribution of pesticides in the Alqueva reservoir, an important source of water supply (South of Portugal), considering their representativeness in the agricultural practice of the area. For the analysis of pesticides risk impact we used the environmental quality standards in the field of water policy proposed recently by the European Commission. The pesticides belonging to the classes of phenylureas, triazines, chloroacetanilides, organophosphorous and thiocarbamates were analysed by on-line solid phase extraction-liquid chromatography-tandem mass spectrometry. The pesticides more frequently detected were atrazine, simazine, diuron and terbuthylazine. The highest levels of these pesticides were registered in spring, after pesticides treatment, namely in olive-tree and vine crops. The priority pesticides atrazine and diuron reached values above the annual average proposed in the European Union Legislation. The herbicide atrazine reached values that surpassed the proposed maximum allowable concentration (2,000 ng L(-1)). The sampling stations most affected by these pesticides were Sra. Ajuda, Lucefecit and Alcarrache, located in the northern part of the reservoir, closer to Spain where the agricultural activity is more intensive.


Assuntos
Exposição Ambiental , Água Doce/química , Praguicidas/análise , Medição de Risco , Poluentes Químicos da Água/análise , Cromatografia Líquida/métodos , Humanos , Espectrometria de Massas/métodos , Portugal , Estações do Ano
13.
Bull Environ Contam Toxicol ; 81(5): 485-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18777155

RESUMO

Ecotoxicological effects of the herbicide atrazine and the insecticides endosulfan sulphate and chlorpyrifos were evaluated using a test battery comprising aquatic organisms from different trophic levels. According to the categories established in the EU legislation, atrazine can be considered non-harmful for the species tested, while the insecticides can be considered very toxic for the crustaceans. The results of acute toxicity tests showed that the sensitivity of organisms were as follows: Thamnocephalus platyurus > Daphnia magna > Vibrio fischeri. Chlorpyrifos may act as a toxic compound in the aquatic environment of Guadiana River, as it may be detected in water at levels that promote toxic effects.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Anostraca/fisiologia , Atrazina/toxicidade , Clorpirifos/toxicidade , Daphnia/fisiologia , Endossulfano/toxicidade , Herbicidas/toxicidade , Inseticidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Portugal , Dicromato de Potássio/toxicidade , Água do Mar/análise
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