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1.
Cardiovasc Toxicol ; 22(6): 558-578, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35429258

RESUMO

Obesity, ethanol, and contaminants are known risk factors of cardiovascular and metabolic diseases (CMD). However, their interplay on clinical profiles of these diseases remains unclear, and thus were investigated in this study. Male lean or obese JCR rats were given water or 10% ethanol and orally treated with or without a contaminant mixture (CM) dissolved in corn oil and loaded on two cookies at 0, 1.6, or 16 mg/kg BW/day dose levels for 4 weeks. The CM consisted 22 environmental contaminants found in human blood or serum of Northern populations. Over 60 parameters related to CMD were examined. The results revealed that obesity in JCR rats resembles the clinical profiles of non-alcoholic fatty liver disease in humans. Obesity was also associated with increased serum and organ retention of mercury, one of the chemical components of CM. Exposure to ethanol lightened hyperlipidemia, increased liver retention of mercury, and increased risk for hypertension in the obese rats. CM lessened hyperlipidemia and hyperenzymemia, worsened systemic inflammation and increased the risk for hypertension in the obese rats. CM markedly increased serum ethanol levels with or without ethanol exposure. Tissue total mercury contents significantly correlated with clinical parameters with altered profiles by both ethanol and obesity. These results suggest that obese individuals may be more prone to contaminant accumulation. Ethanol and CM exposure can alter clinical profiles associated with obesity, which may lead to misdiagnosis of CMD associated with obesity. CM can alter endogenous production and/or metabolism of ethanol, further complicating disease progression, diagnosis, and treatment.


Assuntos
Hipertensão , Mercúrio , Doenças Metabólicas , Animais , Etanol/metabolismo , Etanol/toxicidade , Masculino , Obesidade/complicações , Obesidade/diagnóstico , Ratos
2.
Arch Toxicol ; 92(4): 1453-1469, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29275510

RESUMO

Experimental and/or epidemiological studies suggest that prenatal exposure to bisphenol A (BPA) may delay fetal lung development and maturation and increase the susceptibility to childhood respiratory disease. However, the underlying mechanisms remain to be elucidated. In our previous study with cultured human fetal lung fibroblasts (HFLF), we demonstrated that 24-h exposure to 1 and 100 µM BPA increased GPR30 protein in the nuclear fraction. Exposure to 100 µM BPA had no effects on cell viability, but increased cytoplasmic expression of ERß and release of GDF-15, as well as decreased release of IL-6, ET-1, and IP-10 through suppression of NFκB phosphorylation. By performing global gene expression and pathway analysis in this study, we identified molecular pathways, gene networks, and key molecules that were affected by 100, but not 0.01 and 1 µM BPA in HFLF. Using multiple genomic and proteomic tools, we confirmed these changes at both gene and protein levels. Our data suggest that 100 µM BPA increased CYP1B1 and HSD17B14 gene and protein expression and release of endogenous estradiol, which was associated with increased ROS production and DNA double-strand breaks, upregulation of genes and/or proteins in steroid synthesis and metabolism, and activation of Nrf2-regulated stress response pathways. In addition, BPA activated ATM-p53 signaling pathway, resulting in increased cell cycle arrest at G1 phase, senescence and autophagy, and decreased cell proliferation in HFLF. The results suggest that prenatal exposure to BPA at certain concentrations may affect fetal lung development and maturation, and thereby affecting susceptibility to childhood respiratory diseases.


Assuntos
17-Hidroxiesteroide Desidrogenases/genética , Poluentes Ocupacionais do Ar/toxicidade , Compostos Benzidrílicos/toxicidade , Citocromo P-450 CYP1B1/genética , Estradiol/metabolismo , Pulmão/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Fenóis/toxicidade , Proteína Supressora de Tumor p53/metabolismo , 17-Hidroxiesteroide Desidrogenases/metabolismo , Autofagia , Pontos de Checagem do Ciclo Celular , Senescência Celular/efeitos dos fármacos , Citocromo P-450 CYP1B1/metabolismo , Fibroblastos/efeitos dos fármacos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima
3.
FEBS Lett ; 573(1-3): 181-5, 2004 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-15327995

RESUMO

2D NMR-pH titrations were used to determine pKa values for four conserved tyrosine residues, Tyr45, Tyr85, Tyr96 and Tyr188, in human transferrin. The low pKa of Tyr188 is due to the fact that the iron-binding ligand interacts with Lys206 in open-form and with Lys296 in the closed-form of the protein. Our current results also confirm the anion binding of sulfate and arsenate to transferrin and further suggest that Tyr188 is the actual binding site for the anions in solution. These data indicate that Tyr188 is a critical residue not only for iron binding but also for chelator binding and iron release in transferrin.


Assuntos
Ferro/metabolismo , Transferrina/química , Transferrina/metabolismo , Tirosina/metabolismo , Ânions/metabolismo , Apoproteínas/química , Apoproteínas/metabolismo , Arseniatos/metabolismo , Sítios de Ligação , Humanos , Concentração de Íons de Hidrogênio , Ligantes , Lisina/metabolismo , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Proteica , Sulfatos/metabolismo , Titulometria , Transferrina/genética , Tirosina/genética
4.
J Biol Inorg Chem ; 8(6): 635-43, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12750968

RESUMO

The removal of Fe(III) from human serum transferrin by chelators is thought to proceed through intermediate species in which the chelator becomes associated with the metal center of the protein. The visible spectral shifts associated with the formation of such intermediates in the wild-type (WT) protein are too small for reliable kinetic data to be obtained. Therefore, studies were undertaken with the recombinant N-terminal lobe variant H249A, a variant showing more pronounced spectral changes. The kinetics of the synergistic anion-exchange reaction between nitrilotriacetate (NTA) and carbonate in variant H249A was studied by stopped-flow spectrophotometry as a model for this process in the WT protein. Anion exchange occurs by two pathways at pH 7.4 and 25 degrees C: an NTA-independent dissociative pathway to form a carbonate-free intermediate Fe-H249A (Eq. 1) that subsequently reacts with NTA (Eq. 2):and an NTA-dependent associative pathway (the major pathway) in which a quaternary Fe-H249A-(CO(3))(NTA) intermediate is formed (Eq. 3), which then decays to product (Eq. 4):The reverse reaction, where HCO(3)(-) exchanges for NTA, likewise follows these two pathways. The overall apparent equilibrium constant for formation of Fe-H249A-NTA from Fe-H249A-CO(3) is K'=442 at pH 7.4. The NTA complex is favored over the carbonate complex both kinetically and thermodynamically in the pH range 7.4-8.2.


Assuntos
Ânions/metabolismo , Histidina/metabolismo , Transferrina/metabolismo , Sítios de Ligação , Carbonatos/metabolismo , Histidina/genética , Humanos , Concentração de Íons de Hidrogênio , Transporte de Íons , Ferro/metabolismo , Cinética , Ácido Nitrilotriacético/metabolismo , Proteínas Recombinantes , Espectrofotometria/métodos , Transferrina/genética
5.
Cranio ; 6(3): 217-23, July 1988. ilus
Artigo em Inglês | BBO - Odontologia | ID: biblio-850704

RESUMO

Three-dimensional images were reconstructed from conventional CT scans with the use of special software. These reconstructed images did not exhibit magnification nor superimpositioning of structures. Quantitative measurements of three-dimensional craniofacial structures were very precise, and their form and continuity could be evaluated. The application of this technique will be demonstrated in three cases involved with craniofacial anomalies


Assuntos
Crânio , Face , Tomografia Computadorizada por Raios X
6.
Buenos Aires; Paidós; 1965. 157 p. (Biblioteca del Hombre Contemporáneo, 48).
Monografia em Espanhol | LILACS-Express | BINACIS | ID: biblio-1203974
7.
Buenos Aires; Paidós; 1965. 157 p. (Biblioteca del Hombre Contemporáneo, 48). (81382).
Monografia em Espanhol | BINACIS | ID: bin-81382
8.
Buenos Aires; Eudeba; 1964. 482 p. ilus, tab.
Monografia em Espanhol | LILACS-Express | BINACIS | ID: biblio-1203628
9.
Buenos Aires; Eudeba; 1964. 482 p. ilus, Tab. (80821).
Monografia em Espanhol | BINACIS | ID: bin-80821
10.
Buenos Aires; Eudeba; 1964. 446 p. ilus, Tab. (80820).
Monografia em Espanhol | BINACIS | ID: bin-80820
11.
Buenos Aires; Eudeba; Julio de 1964. 928 p. (88740).
Monografia em Espanhol | BINACIS | ID: bin-88740
12.
Buenos Aires; Eudeba; Julio de 1964. 446 p. (88739).
Monografia em Espanhol | BINACIS | ID: bin-88739
13.
Paris; Press Universitaires de France; 1949. 1183 p. ilus, graf.(Bibliothèque Scientifique Internationale, Sciences Humaines).
Monografia em Francês | Coleciona SUS, IMNS | ID: biblio-922922
14.
Buenos Aires; Editorial Paidós; 1a. ed; 1965. 157 p. ^e17cm.(Biblioteca del hombre contemporáneo, 48).
Monografia em Espanhol | LILACS-Express | BINACIS | ID: biblio-1195593
15.
Buenos Aires; EUDEBA; 1a. ed; 1964. 2v p. ^e24cm.(Tratado de EUDEBA psicología).
Monografia em Espanhol | LILACS-Express | BINACIS | ID: biblio-1196094
16.
Buenos Aires; EUDEBA; 3a. ed; 1971. 446 p. ^e24cm.(Tratados de EUDEBA Psicología).
Monografia em Espanhol | LILACS-Express | BINACIS | ID: biblio-1196095
17.
Buenos Aires; EUDEBA; 3a. ed; 1971. 446 p. 24cm.(Tratados de EUDEBA Psicología). (70456).
Monografia em Espanhol | BINACIS | ID: bin-70456
18.
Buenos Aires; EUDEBA; 2a. ed; 1968. 2v p. 24cm.(Tratados de EUDEBA Psicología). (70455).
Monografia em Espanhol | BINACIS | ID: bin-70455
19.
Buenos Aires; EUDEBA; 1a. ed; 1964. 2v p. 24cm.(Tratado de EUDEBA psicología). (70451).
Monografia em Espanhol | BINACIS | ID: bin-70451
20.
Buenos Aires; Editorial Paidós; 1a. ed; 1965. 157 p. 17cm.(Biblioteca del hombre contemporáneo, 48). (69926).
Monografia em Espanhol | BINACIS | ID: bin-69926
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