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1.
Biometals ; 34(1): 197-210, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33387116

RESUMO

Concentrations of 16 metals in the scalp hair of male Crohn's disease (CD) patients (n = 28) were compared to those of male control subjects (n = 25). The majority of patients (n = 20) took an anti-inflammatory agent (mesalazine), and several patients underwent colectomy. A low concentration of serum ferritin was observed in approximately 50% of CD patients due to Fe-deficiency anemia. The concentrations of Fe, Cr, and Co in the hair of CD patients were significantly higher than those of control subjects, and particularly high concentrations were found in CD patients with low serum ferritin. Significant correlations were found among the concentrations of Fe, Cr, and Co in the hair of CD patients, but not in control subjects. In agreement with previous reports, a significant negative correlation was found between ferritin and transferrin concentrations in serum, although the available data in this study was limited (n = 8). Transferrin not only binds to Fe3+ but also to Cr3+ and Co3+, and the amount of transferrin is increased in Fe-deficiency anemia. Thus, the majority of the Fe3+, Cr3+, and Co3+ in the serum of CD patients is likely to bind to transferrin, which may be associated with the higher concentrations of those metals, as well as the significant correlations among those metals in the scalp hair of CD patients. In addition, colectomy may alter the intestinal absorption rate of some metals, while mesalazine may increase the concentrations of Mn and some metals in the scalp hair by chelate formation.


Assuntos
Doença de Crohn/diagnóstico , Cabelo/química , Oligoelementos/análise , Adolescente , Adulto , Humanos , Masculino , Metaloides/análise , Pessoa de Meia-Idade , Couro Cabeludo , Adulto Jovem
2.
Rapid Commun Mass Spectrom ; 33(1): 41-48, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30280438

RESUMO

RATIONALE: Elental® is an elemental diet widely used as a nutritional supplement for Crohn's disease (CD) patients in Japan. Elental® contains amino acids as nitrogen sources and does not contain selenium (Se), and the δ13 C and δ15 N values of Elental® are markedly higher and lower, respectively, than those of a normal diet. METHODS: We compared the δ13 C and δ15 N values and Se concentration in the scalp hair of CD patients with those of control subjects who ate a regular diet, and estimated the amount of Elental® ingested as a supplement. The δ13 C and δ15 N values and the Se concentrations were quantified using isotope ratio mass spectrometry (IRMS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. RESULTS: An increase in Elental® ingestion increased the δ13 C value in the hair of CD patients (p <0.05), while it reduced the δ15 N value (p <0.05) and tended to reduce the Se concentration in female patients. CONCLUSIONS: The amount of Elental® ingested could be estimated by the δ13 C and δ15 N values in the hair of CD patients. Furthermore, the Se deficiency in female patients may be predicted from the δ13 C and δ15 N values.


Assuntos
Isótopos de Carbono/análise , Doença de Crohn/dietoterapia , Alimentos Formulados , Cabelo/química , Isótopos de Nitrogênio/análise , Adulto , Estudos de Casos e Controles , Suplementos Nutricionais , Ingestão de Energia , Feminino , Humanos , Lipídeos/farmacocinética , Masculino , Espectrometria de Massas/métodos , Avaliação Nutricional , Couro Cabeludo , Selênio/análise
3.
Rapid Commun Mass Spectrom ; 31(9): 745-752, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28225553

RESUMO

RATIONALE: As mercury (Hg) accumulation in marine animals generally increases with increased trophic level (δ15 N values) through the food web, predators accumulate higher levels of Hg. The main source of human Hg intake is the consumption of fish and other marine animals, and Hg concentration in scalp hair is the preferred marker for evaluating consumption of marine animals. Difference in δ15 N values between trophic and source amino acids of human consumers could enable us to estimate the trophic level of the consumer without knowing the bulk δ15 N value of their prey. METHODS: We measured the δ15 N values of 15 amino acids in scalp hair from heavy fish eaters and whale meat eaters using isotope ratio monitoring gas chromatography/mass spectrometry (irm-GC/MS), and investigated the correlations between Hg concentrations in the hair and the δ15 N values of the individual constituent amino acids. RESULTS: The δ15 N values for all trophic amino acids (Ala, Val, Leu, Ile, Pro, Asx and Glx) increased with increases in Hg concentration (p < 0.01), with the highest correlation being with Glx (R2  = 0.725). In contrast, the δ15 N value for Thr decreased with increases in Hg concentration (R2  = 0.663, p < 0.01). The difference in δ15 N values between Glx and Thr was positively correlated with Hg concentration, showing the highest correlation coefficient (R2  = 0.773, p < 0.01) among the various combinations for amino acids. CONCLUSIONS: The difference in δ15 N values between Glx and Thr appears to be the best proxy for the estimation of Hg concentration in scalp hair. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Aminoácidos/química , Isótopos de Carbono/análise , Dieta/estatística & dados numéricos , Cabelo/química , Mercúrio/análise , Isótopos de Nitrogênio/análise , Aminoácidos/análise , Animais , Peixes , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Carne/análise , Couro Cabeludo/fisiologia , Baleias
4.
PLoS One ; 10(6): e0128149, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26065892

RESUMO

We analyzed the Hg concentration, and δ¹³C and δ¹5N values in the scalp hair of residents from seven countries; Vietnam, New Zealand, Spain, the USA, South Korea, Brazil and Japan. Relationships among the data in each country and among the seven countries were then examined. The highest Hg concentration as well as the highest or higher δ¹5N value in each country was found in the hair of a heavy marine fish-eater, whereas the lowest Hg concentration and δ¹5N value were found in the hair of a vegetarian or non (marginal)-fish eater. Hg concentrations were positively correlated with the δ¹5N values in each country, and increased markedly in samples with δ¹5N values exceeding 9.0 ‰, probably due to fish consumption. The highest Hg concentration could be found in sample, with a δ¹³C value between -19 and -18‰, probably reflecting the δ¹³C value of the marine food web.


Assuntos
Isótopos de Carbono , Comportamento Alimentar , Cabelo/química , Mercúrio , Isótopos de Nitrogênio , Animais , Brasil , Peixes , Humanos , Japão , Nova Zelândia , Plantas Comestíveis , República da Coreia , Espanha , Estados Unidos , Vietnã
5.
Mar Pollut Bull ; 69(1-2): 116-21, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23453817

RESUMO

We analyzed stable isotope ratios of carbon (δ(13)C) and nitrogen (δ(15)N) as well as mercury (Hg) concentration in the scalp hair of Japanese who consumed whale meat and those who did not, and investigated the relationships among the δ(13)C and δ(15)N values and Hg concentration. The average δ(15)N and δ(13)C values of whale meat-eaters (10.11‰ and -18.5‰) were significantly higher than those of non-eaters (9.28‰ and -18.9‰), respectively. The average Hg concentration of whale meat-eaters (20.6 µg/g) was significantly higher than that of non-eaters (2.20 µg/g). Significant positive correlations were found between the δ(13)C and δ(15)N values and between the δ(15)N value and Hg concentration in the hair of whale meat-eaters, while the correlation between the δ(15)N value and Hg concentration was not statistically significant in the non-eaters. The consumption of whale meat may increase Hg concentration as well as δ(15)N and δ(13)C values in scalp hair.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/análise , Cabelo/química , Mercúrio/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Isótopos de Carbono/análise , Criança , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Isótopos de Nitrogênio/análise , Adulto Jovem
6.
Biol Pharm Bull ; 35(10): 1745-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23037164

RESUMO

We analyzed the levels of total mercury (T-Hg), methylmercury (M-Hg) and Cd in the muscle and liver of kidako moray eels (Gymnothorax kidako) of different body lengths caught off Kochi Prefecture in southern Japan. Furthermore, we analyzed the levels of organohalogen compounds such as polychlorinated biphenyls (PCBs), p,p'-1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE), trans-nonachlor and 2,3,3',4,4',5,5'-heptachloro-1'-methyl-1-2'-bipyrrole (Q1) and stable isotope ratios of carbon (δ(13)C) and nitrogen (δ(15)N) in the muscle of eels. The concentrations of T-Hg and M-Hg in the muscle (edible part) were 0.31±0.08 µg/wet g and 0.25±0.06 µg/wet g (n=26), respectively, and those in large eels exceeded the Japanese legislated levels of T-Hg (0.4 µg/wet g) and M-Hg (0.3 µg/wet g) in fish and shellfish, respectively. The T-Hg and M-Hg concentrations in the liver were markedly higher than those in the muscle, respectively. The ratios of M-Hg to T-Hg in the muscle and liver were about 80 and 60%, respectively, and those ratios tended to decrease with increased body length. The Cd concentrations in the liver tended to increase proportionally with body length, while that in the muscle was trace (around or below 0.03 µg/wet g). The concentrations of PCBs, p,p'-DDE, trans-nonachlor in the muscle tended to increase proportionally with body length, while that of Q1 did not. The δ(13)C and δ(15)N values in the kidako moray eel were markedly higher than those in offshore habit predators reported elsewhere, which may reflect the inshore habitat of this eels.


Assuntos
Enguias , Fígado/química , Músculos/química , Poluentes Químicos da Água/análise , Animais , Tamanho Corporal , Cádmio/análise , Isótopos de Carbono/análise , Enguias/anatomia & histologia , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Japão , Mercúrio/análise , Compostos de Metilmercúrio/análise , Isótopos de Nitrogênio/análise
7.
Basic Clin Pharmacol Toxicol ; 110(6): 530-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22181038

RESUMO

Mechanisms of transcellular transport of 4-chloro-2-methylphenoxyacetic acid (MCPA) across the small intestine were investigated using Caco-2 cells cultured on permeable membranes. The cell monolayers were incubated with MCPA, either from apical side at pH 6.0 or 7.4, or basolateral side at pH 7.4. The accumulation and apical-to-basolateral transport of MCPA were markedly stimulated by the acidic pH on the apical side (inwardly directed H(+) gradient), dependent on metabolic energy and inhibited by co-incubation with acetic acid or benzoic acid. Without the H(+) gradient, on the other hand, the basolateral-to-apical transport of MCPA (secretory transport) was higher than the apical-to-basolateral transport (absorptive transport), although the secretory transport of MCPA was markedly lower than the absorptive transport under the H(+) gradient. Co-incubation of MCPA with probenecid from the basolateral side significantly inhibited the accumulation and transport of MCPA, whereas co-incubation with p-aminohippuric acid did not. These results suggest that the absorptive transport of MCPA is mediated by H(+)-linked monocarboxylic acid transporters expressed on the apical membranes, while secretory transport is mediated by a probenecid-sensitive transporter expressed on the basolateral membranes of Caco-2 cell monolayers.


Assuntos
Ácido 2-Metil-4-clorofenoxiacético/metabolismo , Absorção Intestinal , Intestino Delgado/metabolismo , Transporte Biológico , Células CACO-2 , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Transportadores de Ácidos Monocarboxílicos/efeitos dos fármacos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Permeabilidade , Probenecid/farmacologia , Temperatura , Fatores de Tempo , Ácido p-Aminoipúrico/farmacologia
8.
Arch Toxicol ; 86(1): 55-61, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21766207

RESUMO

We investigated whether the uptake of triclopyr (3, 5, 6-trichloro-2-pyridinyloxyacetic acid) and dicamba (3,6-dichloro-2-methoxybenzoic acid) across the apical membrane of Caco-2 cells was mediated via proton-linked monocarboxylic acid transporters (MCTs). The uptake of triclopyr from the apical membranes was fast, pH-, temperature-, and concentration dependent, required metabolic energy to proceed, and was competitively inhibited by monocarboxylic acids such as benzoic acid and ferulic acid (substrates of L-lactic acid-insensitive MCTs), but not by L-lactic acid. Thus, the uptake of triclopyr in Caco-2 cells appears to be mediated mainly via L-lactic acid-insensitive MCTs. In contrast, the uptake of dicamba (a benzoic acid derivative) was slow, and it was both pH- and temperature dependent. Coincubation with ferulic acid did not decrease the uptake of dicamba, although coincubation with benzoic acid moderately decreased it. The uptake of dicamba appears to be mediated mainly via passive diffusion, which is in contrast to the uptake of benzoic acid via MCTs. We speculate that the substituted groups in dicamba may inhibit uptake via MCTs.


Assuntos
Dicamba/farmacocinética , Glicolatos/farmacocinética , Herbicidas/farmacocinética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Ácido Benzoico/química , Transporte Biológico , Células CACO-2 , Ácidos Cumáricos/química , Dicamba/administração & dosagem , Relação Dose-Resposta a Droga , Glicolatos/administração & dosagem , Herbicidas/administração & dosagem , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal , Temperatura , Fatores de Tempo
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