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1.
Contraception ; 61(2): 99-103, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10802274

RESUMO

The lining of the uterus and cervix might be injured by a variety of oxidation products of Cu in a Cu-IUD, including cuprous ions, dissolved and precipitated cupric ions, and reactive oxygen species such as superoxide radicals, hydrogen peroxide, and hydroxyl radicals. In this study, the human amnious WISH cell line was employed as a model of uterine cells in the presence of copper. The cell viability was decreased by elemental copper, which was alleviated up to 70% by the addition of catalase. The addition of copper oxychloride caused cell death in a dose-dependent manner. Hydroxyl radicals in the presence of copper were determined by the formation of malondialdehyde. Soluble cuprous chloride complexes are formed in the uterus by slowly entering oxygen. The complexes are partly oxidized to insoluble copper oxychloride. which damages the endometrium. Unoxidized cuprous ions migrate to the oxygen-rich cervix and are oxidized to copper oxychloride, causing cervix damage.


Assuntos
Anticoncepção/métodos , Cobre/metabolismo , Radical Hidroxila/efeitos adversos , Dispositivos Intrauterinos de Cobre/efeitos adversos , Útero/efeitos dos fármacos , Catalase/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cobre/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Humanos , Radical Hidroxila/análise , Vermelho Neutro/química , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Doenças Uterinas/induzido quimicamente , Útero/citologia
2.
Arch Med Res ; 30(3): 163-70, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10427865

RESUMO

BACKGROUND: delta-Aminolevulinic acid (ALA) is recognized as the starter in the biosynthesis of the heme group, the structural basis of cytochromes, chlorophylls, biliary pigments, and other porphyrins. It is the first intermediary in the biosynthesis of protoporphyrin IX (PpIX), and of the heme group. PpIX is present in low concentration in normal cells, and in high concentration in tumor cells. METHODS: The accumulation of protoporphyrin IX (PpIX) induced by delta-aminolevulinic acid (ALA) was tested in two cervico-uterine cancer cell lines (HeLa and CaLo), and in normal human cervical epithelial (NHCE) cells. RESULTS: The optimal concentration of ALA that induced maximum levels of intra- and extracellular accumulation of PpIX in both HeLa and NHCE cells was 300 micrograms of ALA/mL, and for CaLo cells, 150 micrograms/mL. The viability of HeLa, CaLo, and NHCE cells exposed to ALA measured 81, 98, and 84%, respectively. The optimal time for accumulation of PpIX, both intra- and extracellular, was 4 h for HeLa and NHCE cells and 5 h for CaLo cells per 24 h of exposure to optimal concentrations of ALA. After the maximum level of PpIX accumulation was reached, there was a gradual decrease until there was only a small quantity. A statistically significant difference (p < 0.0001) was found in the accumulation of PpIX, depending on the concentrations of ALA used as well as between cervical cancer cell lines and NHCE cells (p < 0.0001). The concentration ratio of PpIX for NHCE and HeLa cells was 1:7, and for NHCE and CaLo cells, 1:5. CONCLUSIONS: These results are important for determining the usefulness of the sensitizer (PpIX).


Assuntos
Ácido Aminolevulínico/farmacologia , Colo do Útero/efeitos dos fármacos , Fármacos Fotossensibilizantes/metabolismo , Protoporfirinas/biossíntese , Neoplasias do Colo do Útero/tratamento farmacológico , Linhagem Celular , Colo do Útero/citologia , Colo do Útero/metabolismo , Feminino , Células HeLa , Humanos , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/patologia
3.
J Toxicol Clin Exp ; 11(3-4): 169-74, 1991.
Artigo em Francês | MEDLINE | ID: mdl-1941704

RESUMO

A study was performed in 278 people living in a Mexican town with a high lead environmental pollution. Lead blood level was found very high (m:59.7 micrograms/l) and some abnormalities were also found for free erythrocyte Protoporphyrin and ALA dehydratase. A significant dose-response relationship was also found with somatic complaints like loss of appetite, insomnia and headache.


Assuntos
Exposição Ambiental , Intoxicação por Chumbo/complicações , Doenças do Sistema Nervoso/induzido quimicamente , População Urbana , Eritrócitos/metabolismo , Humanos , Chumbo/sangue , México , Sintase do Porfobilinogênio/sangue , Protoporfirinas/sangue
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