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1.
J Environ Manage ; 94(1): 25-33, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21890260

RESUMO

Using choice experiment data for economic valuation we analyse how disbelief in survey information could affect the retrieved welfare estimates. We distinguish between two types of survey information to the respondents. The first type of information concerns the current environmental status of a water body. This information is provided prior to the valuation questions and the corresponding beliefs in the provided information are also elicited before valuation. The second type of information concerns the proposed improvements in the environmental status of the water body. We find that average welfare measures differ considerably according to whether respondents who disagree with the status quo levels and find proposed scenarios unlikely are included or not.


Assuntos
Meio Ambiente , Rios , Europa (Continente) , Feminino , Humanos , Masculino , Opinião Pública
2.
Parasitology ; 133(Pt 5): 639-50, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16863602

RESUMO

The monogenean Gyrodactylus salaris Malmberg, 1957 is an economically important parasite on Atlantic salmon whereas the morphologically very similar G. thymalli Zitnan, 1960 on grayling is considered harmless. Even molecular markers cannot unambiguously discriminate both species. The nuclear internal transcribed spacer (ITS) sequences are identical in both species, and although mitochondrial cytochrome oxidase I (COI) sequences show substantial variation, no support for monophyly of either species is found. Analysis of nucleotide sequences of the intergenic spacer (IGS) have, however, been interpreted as support for 2 species. Here, IGS and COI sequences from 81 G. salaris and G. thymalli specimens of 39 populations across the species' distribution range were determined. Mitochondrial diversity was not reflected in the nuclear marker. Since various 23 bp IGS repeat types usually differ by just one nucleotide and sequences primarily differ in the number and order of repeat types, alignments may be biased and arbitrary, impeding meaningful phylogenetic analyses. The hypothesis that parasites on rainbow trout represent hybrids of both species is rejected. The presence or absence of particular repeat types is not considered informative. We interpret the IGS data as support for G. salaris and G. thymalli being a single species.


Assuntos
Núcleo Celular/genética , DNA Intergênico/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Platelmintos/genética , Animais , Oceano Atlântico , DNA de Helmintos/genética , Água Doce , Variação Genética , Proteínas de Helminto/genética , Letônia , Dados de Sequência Molecular , Noruega , Oceanos e Mares , Oncorhynchus mykiss/parasitologia , Platelmintos/classificação , Salmão/parasitologia , Eslováquia , Especificidade da Espécie , Suécia
3.
Protein Sci ; 10(2): 411-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11266626

RESUMO

Mouse urine contains an abundance of major urinary proteins, lipocalins, whose roles include slow release of semiochemicals. These proteins are highly polymorphic, with small sequence differences between individual members. In this study, we purified to homogeneity four of these proteins from two strains of inbred mice and characterized them by mass spectrometry. This analysis has led to the discovery of another variant in this group of proteins. Three of the polymorphic variants that map to the surface have no effect on the binding of a fluorescent probe in the binding cavity, but the fourth, characterized by a Phe to Val substitution in the cavity, shows a substantially lower affinity and fluorescence yield for the probe. These results are interpreted in light of the known crystal structure of the protein and molecular modeling calculations, which rationalize the experimental findings. This work raises the possibility that the calyx-binding site can show specificity for different ligands, the implications of which on pheromone binding and chemical communication are discussed.


Assuntos
Polimorfismo Genético , Urina/química , 1-Naftilamina/análogos & derivados , 1-Naftilamina/química , Sequência de Aminoácidos , Animais , Sítios de Ligação , Relação Dose-Resposta a Droga , Corantes Fluorescentes/química , Ligantes , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Modelos Moleculares , Dados de Sequência Molecular , Método de Monte Carlo , Mapeamento de Peptídeos , Fenilalanina/química , Ligação Proteica , Homologia de Sequência de Aminoácidos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Termodinâmica , Valina/química
4.
Int J Pharm ; 182(1): 1-5, 1999 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-10332069

RESUMO

The bioavailability of melatonin in rabbits after nasal administration of two formulations has been studied. In each case, a total amount of 1.5 mg melatonin in 50 microl was administered and compared with 1.5 mg i.v. The test solutions were formulated with 40% polyethylene glycol 300 (PEG 300), one with 1% sodium glycocholate (+GC) and one without (-GC). The bioavailability for +GC was 94% (S.D.+/-29%, n=4), whereas the bioavailability for -GC was 55% (S.D.+/-17%, n=6). These results indicate that GC has an enhancer effect (P<0.05). However, the relatively high bioavailability without GC shows that it might not be necessary to use an enhancer for a clinical relevant formulation. The pharmacokinetics of melatonin could be described by a one-compartment model, and the serum half-life was about 13 min. The absorption rate for both formulations was very fast (tmax=5 min) and Cmax mean was 493+/-290 ng/ml (n=4) and 249+/-125 ng/ml (n=6) for +GC and -GC, respectively.


Assuntos
Antioxidantes/farmacocinética , Melatonina/farmacocinética , Absorção , Administração Intranasal , Animais , Antioxidantes/administração & dosagem , Disponibilidade Biológica , Compartimentos de Líquidos Corporais , Cromatografia Líquida de Alta Pressão , Meia-Vida , Injeções Intravenosas , Masculino , Melatonina/administração & dosagem , Mucosa Nasal/metabolismo , Veículos Farmacêuticos/farmacologia , Polietilenoglicóis/farmacologia , Coelhos
5.
J Chromatogr B Biomed Sci Appl ; 712(1-2): 177-81, 1998 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-9698240

RESUMO

This paper describes the development of a simple and sensitive analytical method for the quantification of melatonin in human plasma and rabbit serum, using standard analytical equipment and on-line column enrichment without prior extraction, clean-up or derivatization. The analytical procedure was found to be accurate, precise and linear. For human plasma, the accuracy was 101% (range 89-106%), and the mean precision was 5% (range 2-9%) for all concentrations (0, 2, 10, 50 and 200 ng/ml) tested (n=6). The accuracy in rabbit serum was 101% (range 90-112%), and the mean precision was 13% (range 8-19%) for all concentrations (0, 2, 10, 50, 200 and 500 ng/ml) tested (n=6). The retention time of melatonin was about 8 min and the total recoveries were found to be approximately 65 and 85%, respectively, for human plasma and rabbit serum. The limit of detection was found to be lower than 1 ng/ml for human plasma and around 2 ng/ml for rabbit serum. The method is, therefore, found to be suitable for melatonin bioavailability studies in rabbits and presumably also in humans.


Assuntos
Melatonina/sangue , Animais , Cromatografia Líquida de Alta Pressão , Humanos , Coelhos , Sensibilidade e Especificidade , Espectrometria de Fluorescência
6.
Br J Nutr ; 74(4): 557-67, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7577893

RESUMO

A previous study has shown that malnourished, clinically stable patients with liver cirrhosis are in protein and energy balance at their spontaneous dietary intake and that an improvement in nutritional status cannot be anticipated at this intake (Nielsen et al. 1993). In the present study we examined to what extent oral intake could be increased by nutritional support, and to what extent dietary protein would be retained with increased intake. The techniques used for balance studies were also validated since this information is not available for patients with liver cirrhosis. Fifteen malnourished patients with alcoholic liver cirrhosis were given increasing amounts of a balanced ordinary diet for 38 (SE 3) d. Intakes of protein and energy were recorded by weighing servings and leftovers on food trays. Protein intake was calculated from food tables. Total N disposal was calculated after measurement of urinary N excretion, and protein balance was calculated from the N balance. A validation study of protein balance in a subgroup of patients (analysis of N in food by the duplicate portion technique, correction for incomplete recovery of urine by measurement of urinary para-aminobenzoic acid (PABA) after administration of PABA tablets, and measurement of faecal N) did not change protein balance values. Protein intake increased from 1.0 (SE 0.1) g/kg per d to 1.8 (SE 0.1) g/kg per d. With increasing protein intake, 84 (SE 8)% of the increase in intake was retained. The rate of protein retention was not saturated at the intakes obtained in this study. Protein intolerance was only encountered in one patient. Available evidence indicates that the requirement for achieving N balance is increased in these patients but protein retention is highly efficient with increased intake. Protein retention is dependent on energy balance. Energy intake was calculated from food tables and total energy expenditure was calculated by the factorial method. A validation study was performed in a subgroup of patients. The energy contents of food sampled by the duplicate portion technique, and of urine and faeces were measured by bomb calorimetry. Resting energy expenditure (REE) was measured by indirect calorimetry before and at the end of the study, and O2 uptake during bicycle exercise was measured before and at the end of the study. The measured intake of metabolizable energy was on average 13% lower than the value given in food tables. Calculated energy expenditure was not changed by the validation study.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Proteínas Alimentares/administração & dosagem , Cirrose Hepática Alcoólica/metabolismo , Distúrbios Nutricionais/metabolismo , Ingestão de Energia , Metabolismo Energético , Teste de Esforço , Feminino , Humanos , Cirrose Hepática Alcoólica/complicações , Cirrose Hepática Alcoólica/dietoterapia , Masculino , Pessoa de Meia-Idade , Nitrogênio/metabolismo , Nitrogênio/urina , Distúrbios Nutricionais/dietoterapia , Distúrbios Nutricionais/etiologia , Estado Nutricional , Oxigênio/metabolismo
7.
Br J Nutr ; 69(3): 665-79, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8329343

RESUMO

Nutritional assessment and adequacy of spontaneous dietary intake was evaluated in thirty-seven clinically stable hospitalized patients with alcoholic liver cirrhosis. About two-thirds of the patients had ascites or oedema, or both, and, therefore, body weight could not be used for assessment of nutritional status. Lean body mass (LBM; measured by three consecutive 24 h creatinine excretions) was 62 (range 40-95)% of reference values, mid-arm-muscle area (MAMA) was 70 (range 43-115)% and triceps skinfold (TSF) was 45 (range 20-113)% of reference values (all median values). In patients without ascites or oedema, or both, there was a rectilinear correlation between body weight and LBM and between body weight and MAMA (r 0.93 and 0.85 respectively). In patients with ascites or oedema, or both, the correlation between body weight and LBM was poor as could be expected. We suggest that LBM is a useful measure of nutritional status when body weight is unreliable because of ascites or oedema, or both. Energy balance for the group was calculated from energy intake recorded by a 24 h dietary recall and energy expenditure calculated by the factorial method. Median intake was 102 (range 34-176)% of expenditure. N loss was calculated from the average of three 24 h urea excretions. Protein intake was calculated from the 24 h dietary recall. The N balance was positive in the patients as a group (median intake was 120 (range 26-183)% of output). The most malnourished patients tended to have the most positive N balance which was due to a significantly lower N excretion. The protein requirement for N balance was 0.83 (SE 0.05) g/kg per d and only at an intake above 1.20 g/kg per d were all patients in positive N balance. The median intakes of thiamin, folacin, vitamin D, vitamin E, Mg, and Zn were judged to be insufficient. It is concluded that impaired nutritional status is common among patients with liver cirrhosis, even in a stable clinical condition. It is suggested that nutritional status in these patients is evaluated by dietary recalls, in combination with measurement of body weight in patients without ascites or oedema, or both, or in combination with determination of LBM by three 24 h creatinine excretions in patients with ascites or oedema, or both. Criteria for selection of patients that might benefit from nutritional therapy are discussed.


Assuntos
Dieta , Hospitalização , Cirrose Hepática Alcoólica/metabolismo , Avaliação Nutricional , Adulto , Idoso , Idoso de 80 Anos ou mais , Braço , Composição Corporal/fisiologia , Peso Corporal , Creatinina/urina , Proteínas Alimentares/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculos/anatomia & histologia , Nitrogênio/metabolismo , Dobras Cutâneas
8.
Scand J Immunol ; 16(6): 499-507, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6186013

RESUMO

Bone marrow-derived (colony-stimulating factor [CSF]-dependent) diffuse colonies have been shown to include colonies with cytotoxic activity. Such diffuse colonies were expanded for 6-8 weeks in liquid culture medium in the presence of pokeweed mitogen- or concanavalin A-conditioned spleen cell medium (CM). The morphology of the expanded diffuse colony cells (EDCC) was like that of early myelocytic cells. EDCC lost their cytotoxic capacity when expanded, but the cytotoxicity could be reinduced by pretreatment of the colonies with interferon or phorbol ester. Traditional sources of mouse or human CSF such as lung CM, placenta CM and human mononuclear cell CM did not support proliferation of EDCC, whereas partly purified interleukin-3 (IL-3), lacking CSF and IL-2, was stimulatory for EDCC. Thus, the stimulatory factor for EDCC was not CSF but a factor closely related to IL-3. Monoclonal antibodies against T lymphocytes or macrophages did not bind to EDCC. EDCC did not have Fc receptors, but 10% of the cells were positive for a monoclonal anti-Ia antibody. All EDCC were positive for alpha NAE and NASDCI esterases but negative for acid and alkaline phosphatases and peroxidase reactivity; less than 2% of the cells showed metachromatic staining with toluidine. Ultrastructurally, EDCC showed various degrees of cell differentiation but absence of specific cytoplasmatic characteristics such as neutrophilic, eosinophilic, basophilic and mast cell granules. Current work aims to define factors and conditions necessary for the induction of differentiation in these immature monomyelocytic cells.


Assuntos
Medula Óssea/imunologia , Citotoxicidade Imunológica , Células-Tronco Hematopoéticas/imunologia , Animais , Medula Óssea/enzimologia , Células da Medula Óssea , Concanavalina A/farmacologia , Meios de Cultura , Relação Dose-Resposta Imunológica , Hematopoese , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/ultraestrutura , Interferons/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Mitógenos de Phytolacca americana/farmacologia , Ratos , Acetato de Tetradecanoilforbol/farmacologia
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