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2.
Mar Pollut Bull ; 158: 111436, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32753219

RESUMO

Swordfish (Xiphias gladius) is a major marine resource of high economic value to industrial and artisanal fisheries. As a top predator with a long lifespan, it is prone to accumulate high levels of contaminants. The bioaccumulation of a wide range of both legacy and emerging persistent organic contaminants was investigated in the muscle, liver and gonads of swordfish collected from the Seychelles, western Indian Ocean. The detection of all target contaminants, some at frequencies above 80%, highlights their widespread occurrence, albeit at low levels. Mean concentrations in muscle were 5637, 491 and 331 pg g-1 ww for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and perfluoroalkyl substances (PFASs), respectively. ∑BFR mean concentrations were far below, i.e. 47 pg g-1 ww. The data are among the first obtained for such a high diversity of contaminants in an oceanic top predator worldwide and constitute a benchmark of the contamination of Indian Ocean ecosystems.


Assuntos
Hidrocarbonetos Clorados , Praguicidas/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Animais , Bioacumulação , Ecossistema , Monitoramento Ambiental , Oceano Índico , Seicheles
3.
Environ Res ; 188: 109761, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32562947

RESUMO

Tuna and billfish are large pelagic fish of ecological importance in open oceans. As top predators with a long lifespan, they are prone to exposure to various contaminants such as persistent organic pollutants (POPs) and contaminants of emerging concern. In this study, three pollutant families were investigated, including polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and perfluoroalkyl substances (PFASs), including perfluorooctane sulfonate (PFOS) and perfluorocarboxylic acids (PFCAs). Contamination was investigated in individuals from three tropical tuna species, namely bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis) and yellowfin (Thunnusalbacares) tunas and the billfish swordfish (Xiphias gladius), collected from various areas of the western Indian Ocean (WIO) in 2013-2014. Contamination levels and profiles were examined in fish muscle, together with biological parameters (fish length / age, sex, lipid content) and ecological tracers (carbon and nitrogen stable isotopes). POP levels were low in all species in comparison to other locations worldwide, revealing a low impact of anthropogenic organic contaminants in the WIO. A predominance of OCPs (especially DDTs) versus PCBs was highlighted in all species; PFASs were predominant over chlorinated POPs in tunas. Among the studied PFASs, long-chain PFCAs were found to prevail over PFOS in all species. Organic contaminant profiles differed across species according to their foraging habitat; swordfish and bigeye tuna, which both feed in deep oceanic layers, showed similarities in their contaminant profiles. Geographically, the distinct DDT profiles of fish from the Mozambique Channel suggested an exposure to different DDT sources, in line with regional use of this insecticide and coupled with an extended residence time of fish in the Channel. To our knowledge, the data presented here are among the first obtained for legacy and emerging organic contaminants in various species of large pelagic predators from the WIO.


Assuntos
Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Peixes , Humanos , Oceano Índico , Bifenilos Policlorados/análise , Alimentos Marinhos , Poluentes Químicos da Água/análise
4.
J Fish Biol ; 89(5): 2434-2448, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27730635

RESUMO

The lipid composition of somatic and reproductive tissues was determined for female skipjack tuna Katsuwonus pelamis caught in the western Indian Ocean between latitude 10° N and 20° S and longitude 40° and 70° E. The highest total lipid (TL) contents were in the liver and gonads, with white muscle levels approximately three-fold lower. Three lipid classes dominated: triacylglycerols (TAG), sterol esters and wax esters (SE-WE) and phospholipids (PL). Collectively, these accounted for between 70 and 80% of TLs. Changes in lipid concentrations were evaluated over the maturation cycle. Immature fish had the lowest gonad and liver TL levels; concentrations of TL, TAG, SE-WE and PL accumulated from immature to mature (spawning-capable) phase, reflecting sustained vitellogenic activity of the liver and a transfer of lipids to developing oocytes from the onset of vitellogenesis. Gonado-somatic and hepato-somatic indices were positively correlated with each other and positively related to TL in the gonads and liver. Fulton's condition index and lipid concentrations in muscle did not vary significantly over the maturation cycle; fat content in the main storage tissues was undepleted as the ovary developed. Hence, K. pelamis apparently supports reproduction directly from food intake over the breeding season. In the gonads, reserve lipids (SE-WE and TAG) and sterols were related to batch fecundity but this was not the case for somatic and hepatic tissues. These results suggest that K. pelamis utilizes an income breeding strategy.


Assuntos
Metabolismo Energético , Metabolismo dos Lipídeos , Reprodução , Atum/metabolismo , Animais , Feminino , Fertilidade , Oceano Índico , Lipídeos , Fígado/metabolismo , Oogênese , Ovário/metabolismo , Estações do Ano
5.
Environ Res ; 148: 196-206, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27084988

RESUMO

The contamination of albacore tuna (Thunnus alalunga) by Persistent Organic Pollutants (POPs), namely polychlorinated biphenyls (PCBs) and dichlorodiphenyl-trichloroethane (DDT), was investigated in individuals collected from Reunion Island (RI) and South Africa's (SA) southern coastlines in 2013, in relation to biological parameters and feeding ecology. The results showed lower PCB and DDT concentrations than those previously reported in various tuna species worldwide. A predominance of DDTs over PCBs was revealed, reflecting continuing inputs of DDT. Tuna collected from SA exhibited higher contamination levels than those from RI, related to higher dietary inputs and higher total lipid content. Greater variability in contamination levels and profiles was identified in tuna from RI, explained by a higher diversity of prey and more individualistic foraging behaviour. PCB and DDT contamination levels and profiles varied significantly in tuna from the two investigated areas, probably reflecting exposure to different sources of contamination.


Assuntos
DDT/análise , Bifenilos Policlorados/análise , Atum/metabolismo , Poluentes Químicos da Água/análise , Animais , Tamanho Corporal , Monitoramento Ambiental , Feminino , Cadeia Alimentar , Conteúdo Gastrointestinal/química , Gônadas/crescimento & desenvolvimento , Oceano Índico , Metabolismo dos Lipídeos , Fígado/crescimento & desenvolvimento , Masculino , Músculo Esquelético/química , Tamanho do Órgão , África do Sul
6.
Chemosphere ; 98: 66-72, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24238912

RESUMO

The contamination of the Gironde Estuary, southwest of France, by polychlorinated biphenyls (PCBs) was assessed using six fish of high ecological and economic importance as bioindicator species. The concentrations of 21 PCB congeners and total fat contents were determined in the muscle and liver of eels (Anguilla anguilla), seabass (Dicentrarchus labrax), flounders (Platichthys flesus), meagres (Argyrosomus regius), mullets (Liza ramada), and soles (Solea vulgaris). In addition, information regarding the trophic ecology of the studied fish was obtained through the analysis of carbon and nitrogen stable isotopes (i.e., δ(13)C and δ(15)N) in muscle. Results revealed high PCB concentrations in fish compared to monitored European estuaries. The muscle of eels was by far the most contaminated fish flesh (Σ7PCBs=1000±440 ng g(-1) on a dry weight basis), while the higher PCB concentrations in liver were measured in flounder (Σ7PCBs=2040±1160 ng g(-1) d.w.). A quantile regression approach allowed to investigate the fate of PCBs in the Gironde estuarine fish assemblage, and revealed a general process of trophic magnification. Finally, most of the analysed fish presented PCB concentrations in muscle meat above the current European maximum limits for sea products, while the derived "Toxic Equivalent Quantity" (TEQ) revealed human health concerns only for high-fat fish consumption.


Assuntos
Monitoramento Ambiental , Estuários , Peixes/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Enguias/metabolismo , Linguado/metabolismo , França , Oceanos e Mares , Perciformes/metabolismo , Bifenilos Policlorados/análise , Smegmamorpha/metabolismo , Poluentes Químicos da Água/análise
7.
Chemosphere ; 90(2): 150-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22795073

RESUMO

The inorganic contamination of sediment and harvested molluscs was investigated in the mangrove environment of Southern West Senegal. Trace metals were analysed in surface sediments, two bivalves (Arca senilis and Crassostera gasar) and three gastropods (Conus spp., Hexaplex duplex and Pugilina morio) collected from four stations: Dionewar, Niodor and Falia localised in the Saloum Delta, and Fadiouth from the Petite Côte. A geochemical normalisation approach by using aluminium allowed for discrimination of sediment contamination among sites. Indeed, Fadiouth appeared highly contaminated with Cd, Hg and Ni compared to the Saloum Delta. For all mangrove sites, trace metals exhibited significant higher concentrations (on a dry weight basis) in shellfish compared to sediments, excepted for Ni and Pb. The distribution pattern followed a similar global trend in molluscs regardless of the spatio-temporal variability, with the predominance of Zn (80% of total metals) followed by Cu and Cd. However, strong differences of metal bioavailability and bioaccumulation in biota were demonstrated, revealing the requirement of employing a suite of organism bioindicators to monitor metal contamination in mangrove ecosystems. From an ecotoxicological point of view, trace metal levels in sediments from the Petite Côte and the Sine-Saloum Estuary were below the effects range-low (ERL) threshold limit of the sediment quality guidelines for adverse biological effects (SQGs). On the opposite, some concerns about Cd contamination of edible shellfish from Southern West Senegal were highlighted, from both the safety point of view of local populations' health, and the chemical quality point of view of exported resources.


Assuntos
Ecossistema , Metais/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Animais , Bivalves/metabolismo , Monitoramento Ambiental , Gastrópodes/metabolismo , Sedimentos Geológicos/química , Metais/metabolismo , Senegal , Poluentes Químicos da Água/metabolismo
8.
Chemosphere ; 84(3): 318-27, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21550627

RESUMO

The surface sediments, two bivalves (Arca senilis and Crassostera gasar) and three gastropods (Conus spp., Hexaplex duplex and Pugilina morio) from two Senegalese stations, Falia (Sine-Saloum Estuary) and Fadiouth (Petite Côte), were analyzed for their pollutant organic persistent contamination (polychlorinated biphenyls PCBs; organochlorinated pesticides OCPs; polybrominated diphenyl ethers PBDEs). Results revealed significant levels of PCBs, DDTs and lindane in mangrove sediments ranging from 0.3 to 19.1, 0.3 to 15.9, and 0.1 to 1.9 ng g(-1) d.w., respectively. Among the other POPs analysed, only hexachlorobenzene, heptachlor and trans-nonachlor for OCPs, as well as BDE47 and BDE99 congeners for PBDEs were detected at very low concentrations, generally not of concern. POP levels and patterns were in good accordance with literature data available for other tropical developing countries. A seasonal quantitative difference was highlighted with higher levels of PCBs and DDTs in sediments after the wet season, likely due to the strong wash-out of residues from inland to the marine ecosystems during the rainy season. The observed pattern of DDT and its metabolites pointed out probable recent applications of DDT for public health emergencies in Senegal. Exploited molluscs were exposed to the same POP compounds as those measured in sediments. They presented OCP levels within the same range as in sediments, while significant higher concentrations of PCBs were observed in shellfish soft tissues revealing a higher bioaccumulation potential mainly due to the lipophilicity of these compounds. Finally, the influence of the reproduction cycle on POP levels through lipid content variations was highlighted, minimizing potential differences in POP bioaccumulation between shellfish species. From an ecotoxicological and public health point of view, results from this study revealed that POPs in sediments from the Petite Côte and the Sine-Saloum Estuary would not cause toxic effects and impairments in molluscs from these regions, and that no potential risk exists for human, especially local populations, through mangrove shellfish consumption.


Assuntos
Bivalves/metabolismo , Gastrópodes/metabolismo , Compostos Orgânicos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Ecossistema , Monitoramento Ambiental , Pesqueiros/estatística & dados numéricos , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/metabolismo , Heptacloro/análise , Heptacloro/metabolismo , Hexaclorobenzeno/análise , Hexaclorobenzeno/metabolismo , Hexaclorocicloexano/análise , Hexaclorocicloexano/metabolismo , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/metabolismo , Compostos Orgânicos/análise , Praguicidas/análise , Praguicidas/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Rhizophoraceae , Estações do Ano , Senegal , Poluentes Químicos da Água/análise
9.
Comp Biochem Physiol B Biochem Mol Biol ; 156(4): 237-43, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20363355

RESUMO

Supplies of marine fish oils are limited, and continued growth in aquaculture production dictates that lipid substitutes in fish diets must be used without compromising fish health and product quality. In this study, the total substitution of a fish meal and fish oil by a blend of vegetable meals (corn, soybean, wheat and lupin) and linseed oil in the diet of European sea bass (Dicentrachus labrax) was investigated. Two groups of European sea bass were fed with fish diet (FD) or vegetable diet (VD) for 9months. VD, totally deprived of eicosapentaenoate (EPA; 20:5n-3) and docosahexaenoate (DHA; 22:6n-3), revealed a nutritional deficiency and affected growth performance. Whilst VD induced a significant increase in fatty acid desaturase 2 (FADS2) and sterol binding regulatory element-binding protein 1 (SREBP-1) mRNA levels, the desaturation rate of [1-(14)C]18:3n-3 into [1-(14)C]18:4n-3, analysed in microsomal preparations using HPLC method, did not show an upregulation of FADS2 activities in liver and intestine of fish fed VD. Moreover Western-blot analysis did not revealed any significant difference of FADS2 protein amount between the two dietary groups. These data demonstrate that sea bass exhibits a desaturase (FADS2) activity whatever their diet, but a post-transcriptional regulation of fads2 RNA prevents an increase of enzyme in fish fed a HUFA-free diet. This led to a lower fish growth and poor muscle HUFA content.


Assuntos
Bass/metabolismo , Dieta , Ácidos Graxos Dessaturases/metabolismo , Proteínas de Peixes/metabolismo , Ração Animal , Animais , Aquicultura , Bass/genética , Bass/crescimento & desenvolvimento , Ácidos Graxos Dessaturases/genética , Ácidos Graxos/análise , Proteínas de Peixes/genética , Regulação da Expressão Gênica , Intestinos/enzimologia , Fígado/enzimologia , PPAR alfa/genética , PPAR alfa/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Verduras
10.
Environ Pollut ; 151(1): 252-61, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17544187

RESUMO

Polychlorobiphenyls (PCB) and stable isotopes (delta15N and delta13C) were analyzed in the spider crab (Maja brachydactyla) food web from the Iroise Sea (Western Brittany) and the Seine Bay (Eastern English Channel). PCB concentrations were all significantly higher in organisms from the Seine Bay than those from the Iroise Sea. PCB patterns were strongly related to the feeding mode of the species, and increased influence of higher chlorinated congeners was highlighted with trophic position of the organisms. PCB concentrations (lipid normalized) were significantly related to the isotopically derived trophic level (TL) in spider crab food webs. The highest trophic magnification factors (TMFs) were calculated for the congeners with 2,4,5-substitution, and were lower in the Seine Bay compared to the Iroise Sea. The confrontation of PCB and TL data also revealed biotransformation capacity of decapod crustaceans for specific congeners based on structure-activity relations.


Assuntos
Decápodes/metabolismo , Monitoramento Ambiental/métodos , Cadeia Alimentar , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Animais , Bivalves , Isótopos de Carbono , Equinodermos , Eucariotos , França , Gastrópodes , Geografia , Isótopos de Nitrogênio , Bifenilos Policlorados/química , Relação Estrutura-Atividade , Poluentes Químicos da Água/química , Zooplâncton
11.
Mar Pollut Bull ; 54(6): 657-68, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17434539

RESUMO

Polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analysed in the muscle of various edible marine crustaceans (spider crab, edible crab, velvet swimming crab and Norway lobster) from the Brittany and Normandy coasts (France). The highest concentrations were measured in species collected from Antifer (Seine Bay). PCB and PBDE patterns in crustacean muscles were similar and independent of the geographical area with the predominance of the high chlorinated PCBs (CB153, 138, 118 and 180), and of a few PBDE congeners (BDE47, BDE99, BDE100 and BDE28). Oppositely, dioxin contamination differed with site. The major component in crustaceans from the Seine Bay was 2378-TCDF, whereas specimens from cleaner areas had higher relative concentrations of OCDD. Finally, the comparison of the spider crab contaminant profiles to those measured in mussel and sea bass highlighted two different trends: decapod crustaceans possess relatively strong capacity to metabolise PCBs and PBDEs; however these species might be used as bioindicators for dioxin pollution monitoring in the marine coastal environment.


Assuntos
Decápodes/metabolismo , Água do Mar/química , Poluentes Químicos da Água/metabolismo , Animais , Oceano Atlântico , Bass/metabolismo , Benzofuranos/metabolismo , Bioensaio , Bivalves/metabolismo , Monitoramento Ambiental , França , Bifenil Polibromatos/metabolismo , Bifenilos Policlorados/metabolismo , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/metabolismo
12.
Chemosphere ; 67(9): S36-47, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17223177

RESUMO

The contamination and distribution of organochlorinated compounds were considered in three crustacean species (edible crab, Cancer pagurus; spider crab, Maja brachydactyla; velvet swimming crab, Necora puber) from five sites along the coasts of Brittany and Normandy (Western and North-Western France). PCBs (16 single congeners), pp'-DDE and HCB were measured in hepatopancreas, gonads and muscle: in all, 175 samples were analysed. The spider crab was the only species found in the five sampling sites, thus enabling comparison between areas. Specimens from Antifer were much more contaminated (summation operator 16 PCBs in hepatopancreas=2000-4000 ng g(-1) dry weight) than those from other sites (50-1000 ng g(-1) d.w.). Among all the three species, the spider crab appeared more contaminated by PCBs than the edible crab, by a factor 2-3, probably in relation with specific differences in their life cycle. There was no difference due to the gender of the species. Within the different analysed tissues, contamination levels increased from muscle to gonads and hepatopancreas in relation with the fat content. A very similar PCB composition was observed in all samples, PCB fingerprints being characterised by the relative importance of the more persistent PCB congeners: CB153, 138, 180, 187, and 118. Finally, these results were compared to recent food regulations first of maximum marker PCB intake and secondly of maximum dioxin-like PCB intake. By considering the muscle, all samples were far below the regulatory limits; for hepatopancreas and gonads, however, some samples were unfit for human consumption.


Assuntos
Decápodes/química , Contaminação de Alimentos/análise , Hidrocarbonetos Clorados/análise , Poluentes Químicos da Água/análise , Animais , França , Geografia , Gônadas/química , Hepatopâncreas/química , Humanos , Hidrocarbonetos Clorados/metabolismo , Carne/normas , Músculos/química , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Fatores de Risco , Poluentes Químicos da Água/metabolismo
13.
Comp Biochem Physiol C Toxicol Pharmacol ; 138(4): 411-27, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15536049

RESUMO

Seasonal variations of six mussel (Mytilus galloprovincialis) biomarkers at two sites in the Mediterranean Sea were compared with physiological indices (condition, growth and gonad maturation), environmental parameters (temperature, salinity and turbidity), and chemical contamination levels. The basal levels of acetylcholinesterase (AChE), DNA adducts, benzo[a]pyrene hydroxylase (BPH), heat-shock proteins (HSP70), metallothioneins (MT) and P-glycoprotein (P-gp)-mediated multixenobiotic resistance (MXR) were estimated as early warning signals in caged mussels sampled at Carteau (native site) and La Fourcade (transplantation site) over a 2-year period. The Carteau and La Fourcade mussels have specific chemical contamination profiles but a similar range of values. For example, both are highly contaminated by heavy metals (201 and 258.4 mg kg(-1) dw, respectively) and considered as moderately impacted for polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). However, contamination levels at Carteau are twice as high for PAHs (101.5 mg g(-1) dw) and PCBs (90.2 mg g(-1) dw) than La Fourcade. The seasonal contamination trend at Carteau showed six-fold higher levels of pyrolytic pollutants in winter. Although few tissue lesions were detected in individuals studied at either site, greater parasitic infestation was observed at Carteau. The results of findings from the two Mediterranean pilot studies support the adaptability of transplanted mussels to be used as biomarkers and to establish physiological endpoints for chemical contaminant exposure.


Assuntos
Bivalves/efeitos dos fármacos , Exposição Ambiental/análise , Estações do Ano , Frutos do Mar , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/análise , Bivalves/química , Bivalves/metabolismo , Monitoramento Ambiental/métodos , Mar Mediterrâneo , Xenobióticos/análise , Xenobióticos/metabolismo , Xenobióticos/toxicidade
14.
J Marital Fam Ther ; 15(4): 397-410, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21118468

RESUMO

Working with a treatment and observing team at the same time, behind the oneway mirror, offers a variety of ways to: (a) generate multiple realities; (b) work with two different models of family therapy simultaneously; and (c) provide feedback on the teams' own roles, rules and group process. The process that 6 trainees and two supervisors used with T and O teams to examine their own coevolution as a therapeutic system using the Milan model of family therapy and Ericksonian hypnotherapy is described. The article concludes with a discussion of the advantages and pitfalls of this type of dual supervision.

15.
Gut ; 23(12): 1081-7, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7173720

RESUMO

A series of experiments has been performed in healthy male volunteers to investigate the disposition of orally administered disodium azodisalicylate, a potentially useful drug for the treatment of ulcerative colitis. The drug was given by mouth in doses of up to 2 g a day for six weeks and there were no adverse effects. Serum concentrations of the intact compound were low and the serum half-time was 4-12.8 days, probably because of a combination of a low clearance rate and a high apparent volume of distribution. Less than 5% of the ingested dose was excreted unchanged in the urine. Circulating concentrations of 5-ASA and N-acetyl-5-ASA were low and 30% of the equivalent daily dose was excreted in the urine, predominantly as N-acetyl-5-ASA. In most subjects more than 30% of the equivalent daily dose of 5-ASA was recovered from the faeces, either as 5-ASA itself or as the acetylated derivative. As 5-ASA has been shown to be the active therapeutic moiety of sulphasalazine, disodium azodisalicylate appears to be suitable for therapeutic trial in ulcerative colitis.


Assuntos
Ácidos Aminossalicílicos/metabolismo , Adulto , Idoso , Ácidos Aminossalicílicos/administração & dosagem , Ácidos Aminossalicílicos/efeitos adversos , Colite Ulcerativa/tratamento farmacológico , Esquema de Medicação , Fezes/análise , Meia-Vida , Humanos , Rim/metabolismo , Cinética , Masculino , Pessoa de Meia-Idade
16.
Clin Pharmacol Ther ; 26(4): 473-82, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-487695

RESUMO

d-Propoxyphene kinetics was studied in 8 healthy male subjects after single oral doses of d-propoxyphene at 65, 130, and 190 mg and after slow intravenous infusion of 65 mg. Total urinary excretion (7 days) indicated complete oral absorption but systemic availability was reduced corresponding to fist-pass elimination of 30% to 70%. There was linearity between oral dose and the corresponding area under the plasma concentration/time curve of d-propoxyphene and the metabolite norpropoxyphene. The kinetic measurements showed 2- to 3-fold interindividual variations: oral clearance, 1.3 to 3.6 1/min; systemic clearance, 0.6 to 1.2 1/min; apparent volume of distribution, 700 to 1,800 1; d-propoxyphene half-life (t1/2), 8 to 24 hr; and norpropoxyphene t1/2, 18 to 29 hr. There were pronounced intraindividual dose-dependent variations in oral clearance in some subjects. The intravenous concentration curves indicated a 3-compartment distribution model.


Assuntos
Dextropropoxifeno/administração & dosagem , Administração Oral , Adulto , Dextropropoxifeno/sangue , Dextropropoxifeno/urina , Avaliação de Medicamentos , Humanos , Injeções Intravenosas , Cinética , Masculino
17.
Acta Med Scand ; 203(1-2): 121-4, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-626106

RESUMO

The single-dose kinetics of D-propoxyphene, acetyl salicylic acid and phenazone, given in a combination tablet (Doleron), were compared in young and elderly subjects. Serial blood samples were taken 0--48 hours after administration. The plasma concentrations of propoxyphene and of its major metabolite, norporpoxyphene, were assessed by mass fragmentography, those of phenazone by gas chromatography, and those of acetyl salicylic acid plus salicylic acid by spectrofluorometry. Neither for propoxyphene, norpropoxyphene, acetyl salicylic acid nor phenazone did the areas under the concentration curves or the elimination half-lives differ between young and elderly subjects. These data do not provide pharmacokinetic support for a general reduction of the Doleron dosage in elderly subjects.


Assuntos
Antipirina/metabolismo , Aspirina/metabolismo , Dextropropoxifeno/metabolismo , Administração Oral , Adulto , Fatores Etários , Idoso , Antipirina/administração & dosagem , Aspirina/administração & dosagem , Dextropropoxifeno/administração & dosagem , Combinação de Medicamentos , Feminino , Humanos , Absorção Intestinal , Masculino , Comprimidos
18.
Acta Med Scand ; 202(1-2): 119-24, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-899874

RESUMO

The influence of food intake on the bioavailability of three analgesic compounds--propoxyphene chloride, acetyl salicylic acid and phenazone--in a combination tablet, Doleron, has been examined in eight healthy volunteers. A single oral dose was given both on an empty stomach and together with a standardized breakfast meal. The plasma concentrations of propoxyphene, its major metabolite norpropoxyphene, salicylic acid and phenazone were determined by mass fragmentography, spectrofluorimetry and gas chromatography. Concomitant food intake had no consistent influence on the bioavailability of any of the components. Hence, doleron may be taken together with meals as well as between meals. Large interindividual variations in propoxyphene and phenazone concentrations were found, indicating that an optimal effect will not always be obtained by standard doses.


Assuntos
Antipirina/metabolismo , Aspirina/metabolismo , Dextropropoxifeno/metabolismo , Alimentos , Adulto , Disponibilidade Biológica , Combinação de Medicamentos , Jejum , Feminino , Humanos , Masculino
19.
Antimicrob Agents Chemother ; 8(5): 518-25, 1975 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1211909

RESUMO

Bacampicillin (proposed international nonproprietary name), 1'-ethoxycarbonyloxyethyl 6-(d-alpha-aminophenylacetamido)penicillanate, is a new orally well-absorbed penicillin, highly active in vivo due to rapid transformation into ampicillin. The compound is stable in vitro at gastric pH and hydrolyzed slowly to ampicillin at neutral pH but very rapidly in the presence of biological fluids, e.g., tissue homogenates or serum. In vivo the transformation into ampicillin is so rapid that no unchanged compound could be detected in the blood after oral administration of bacampicillin to rats, dogs, and humans. On oral administration to mice, rats, and dogs, bacampicillin was found to be better absorbed than ampicillin, giving higher and earlier peak blood levels of ampicillin. The bioavailability of bacampicillin in rats and dogs was three to four times higher than that of an equimolar amount of ampicillin. On oral administration to rats, bacampicillin was found to give higher levels of ampicillin in organs such as the kidney, liver, and spleen than ampicillin itself. In "tissue cages" in rats, higher transudate levels of antibiotic were found after oral administration of bacampicillin than after ampicillin. On oral treatment of experimentally infected mice, bacampicillin was found to be more active than ampicillin.


Assuntos
Ampicilina/análogos & derivados , Ampicilina/metabolismo , Ampicilina/uso terapêutico , Animais , Infecções Bacterianas/tratamento farmacológico , Cães , Feminino , Hidrólise , Absorção Intestinal , Masculino , Camundongos , Ratos , Especificidade da Espécie
20.
Xenobiotica ; 5(9): 521-9, 1975 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1189465

RESUMO

1. The absorption from the respiratory tract and biotransformation of three bronchodilating drugs, terbutaline, ibuterol (diisobutyrate ester of terbutaline) and isoproterenol, have been studied in rats after endotracheal instillation. 2. At 2-15 min after dosage, ibuterol is more rapidly absorbed from the respiratory tract than terbutaline, but later (15-35 min), absorption of ibuterol is about the same as terbutaline. Absorption of isoproterenol is rapid throughout the experiment. Absorption rates have been related to the physical-chemical properties of the compounds. 3. No significant biotransformation of terbutaline was noted in the rat lung at any time after dosage, but ibuterol is extensively hydrolysed to terbutaline. Extensive biotransformation of isoproterenol to 3-methoxy-isoproterenol and an unidentified metabolite occurred. Metabolites of terbutaline and isoproterenol were found in serum and liver.


Assuntos
Broncodilatadores/metabolismo , Isoproterenol/metabolismo , Terbutalina/análogos & derivados , Terbutalina/metabolismo , Animais , Biotransformação , Broncodilatadores/sangue , Butiratos/sangue , Butiratos/metabolismo , Intubação Intratraqueal , Isoproterenol/sangue , Fígado/metabolismo , Pulmão/metabolismo , Masculino , Especificidade de Órgãos , Ratos , Terbutalina/sangue
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