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1.
Sci Total Environ ; 833: 154871, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35364180

RESUMO

Electronic waste (WEEE; from TV screens to electric toothbrushes) is one of the fastest growing waste streams in the world. Prior to recycling, e-waste components (metals, wood, glass, etc.) are processed by shredding, grinding and chainsaw cutting. These activities generate fine and ultrafine particle emissions, containing metals as well as organics (e.g., flame retardants), which have high potential for human health impacts as well as for environmental release. In this work, release of fine and ultrafine particles, and their exposure impacts, was assessed in an e-waste recycling facility under real-world operating conditions. Parameters monitored were black carbon, particle mass concentrations, ultrafine particles, and aerosol morphology and chemical composition. Potential health impacts were assessed in terms of cytotoxicity (cell viability) and oxidative stress (ROS) on <2 µm particles collected in liquid suspension. Environmental release of WEEE aerosols was evidenced by the higher particle concentrations monitored outside the facility when compared to the urban background (43 vs.11 µgPM2.5/m3, respectively, or 2.4 vs. 0.2 µgCa/m3). Inside the facility, concentrations were higher in the top than on the ground floor (PM2.5 = 147 vs. 78 µg/m3, N = 15.4 ∗ 104 vs. 8.7 ∗ 104/cm3, BC = 12.4 vs. 7.2 µg/m3). Ventilation was a key driver of human exposure, in combination with particle emissions. Key chemical tracers were Ca (from plastic fillers) and Fe (from wiring and other metal components). Y, Zr, Cd, Pb, P and Bi were markers of cathode TV recycling, and Li and Cr of grinding activities. While aerosols did not evidence cytotoxic effects, ROS generation was detected in 4 out of the 12 samples collected, associated to the ultrafine fraction. We conclude on the need for studies on aerosol emissions from WEEE facilities, especially in Europe, due to their demonstrable environmental and human health impacts and the rapidly growing generation of this type of waste.


Assuntos
Resíduo Eletrônico , Retardadores de Chama , Aerossóis/análise , Resíduo Eletrônico/análise , Monitoramento Ambiental , Retardadores de Chama/análise , Retardadores de Chama/toxicidade , Humanos , Metais/toxicidade , Material Particulado/análise , Espécies Reativas de Oxigênio
2.
Antimicrob Agents Chemother ; 53(11): 4840-4, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19721063

RESUMO

Previously it has been shown that tipranavir-ritonavir (TPV/r) does not affect efavirenz (EFV) plasma concentrations. This study investigates the effect of steady-state EFV on steady-state TPV/r pharmacokinetics. This was a single-center, open-label, multiple-dose study of healthy adult female and male volunteers. TPV/r 500/200 mg twice a day (BID) was given with food for 24 days. After dosing with TPV/r for 10 days, EFV 600 mg once a day was added to the regimen. Intensive pharmacokinetic (PK) sampling was done on days 10 and 24. Validated bioanalytical high-pressure liquid chromatography-tandem mass spectrometry methods were used to determine plasma tipranavir (TPV), ritonavir (RTV), and EFV concentrations. Thirty-four subjects were entered into the study, and 16 subjects completed it. The geometric mean ratios (90% confidence intervals) for TPV and RTV area under the curves, C(max)s, and C(min)s comparing TPV/r alone and in combination with EFV were 0.97 (0.87 to 1.09), 0.92 (0.81 to 1.03), and 1.19 (0.93 to 1.54) for TPV and 1.03 (0.78 to 1.38), 0.92 (0.65 to 1.30), and 1.04 (0.72 to 1.48) for RTV. Frequently observed adverse events were diarrhea, headache, dizziness, abnormal dreams, and rash. EFV had no effect on the steady-state PK of TPV or RTV, with the exception of a 19% increase in the TPV C(min), which is not clinically relevant. TPV/r can be safely coadministered with EFV and without the need for a dose adjustment.


Assuntos
Fármacos Anti-HIV/farmacocinética , Benzoxazinas/farmacologia , Piridinas/farmacocinética , Pironas/farmacocinética , Ritonavir/farmacocinética , Adolescente , Adulto , Alcinos , Fármacos Anti-HIV/farmacologia , Ciclopropanos , Interações Medicamentosas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sulfonamidas
3.
Antimicrob Agents Chemother ; 53(10): 4385-92, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19667285

RESUMO

To identify pharmacokinetic (PK) drug-drug interactions between tipranavir-ritonavir (TPV/r) and rosuvastatin and atorvastatin, we conducted two prospective, open-label, single-arm, two-period studies. The geometric mean (GM) ratio was 1.37 (90% confidence interval [CI], 1.15 to 1.62) for the area under the concentration-time curve (AUC) for rosuvastatin and 2.23 (90% CI, 1.83 to 2.72) for the maximum concentration of drug in serum (Cmax) for rosuvastatin with TPV/r at steady state versus alone. The GM ratio was 9.36 (90% CI, 8.02 to 10.94) for the AUC of atorvastatin and 8.61 (90% CI, 7.25 to 10.21) for the Cmax of atorvastatin with TPV/r at steady state versus alone. Tipranavir PK parameters were not affected by single-dose rosuvastatin or atorvastatin. Mild gastrointestinal intolerance, headache, and mild reversible liver enzyme elevations (grade 1 and 2) were the most commonly reported adverse drug reactions. Based on these interactions, we recommend low initial doses of rosuvastatin (5 mg) and atorvastatin (10 mg), with careful clinical monitoring of rosuvastatin- or atorvastatin-related adverse events when combined with TPV/r.


Assuntos
Fármacos Anti-HIV/farmacocinética , Fluorbenzenos/farmacocinética , Ácidos Heptanoicos/farmacocinética , Piridinas/farmacocinética , Pirimidinas/farmacocinética , Pironas/farmacocinética , Pirróis/farmacocinética , Ritonavir/farmacocinética , Sulfonamidas/farmacocinética , Adolescente , Adulto , Idoso , Fármacos Anti-HIV/efeitos adversos , Atorvastatina , Interações Medicamentosas , Feminino , Fluorbenzenos/efeitos adversos , Ácidos Heptanoicos/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Piridinas/efeitos adversos , Pirimidinas/efeitos adversos , Pironas/efeitos adversos , Pirróis/efeitos adversos , Ritonavir/efeitos adversos , Rosuvastatina Cálcica , Sulfonamidas/efeitos adversos , Adulto Jovem
4.
HIV Med ; 10(9): 548-54, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19515092

RESUMO

OBJECTIVES: For individuals not on antiretroviral therapy, the risk of heterosexual transmission of HIV appears negligible when blood plasma (BP) viral loads are <1500 HIV-1 RNA copies/mL. It is not clear whether this observation can be extrapolated to individuals on highly active antiretroviral therapy (HAART). Because of differential tissue penetration, antiretroviral drug concentrations may be sufficient to maintain an undetectable viral load in the BP yet not achieve adequate levels to suppress HIV in the genital tract. Therefore, we wanted to correlate HIV viral loads and drug concentrations in semen plasma (SP) and BP. METHODS: Thirty-three men were included. All were on combination antiretroviral therapy with an undetectable BP viral load for at least 1 year. Blood and semen samples were collected within 2 h of each other and tested for HIV RNA by the NucliSens QT (bioMerieux, St Laurent, QC, Canada) method; drug concentrations were determined by liquid chromatography tandem mass spectrometry. RESULTS: Two of the 33 patients (6.1%) with BP viral loads below detection had time-matched HIV viral loads in SP > or =700 copies/mL. Both patients were on efavirenz, the SP concentrations of which were < or =10% of the levels in BP and well below the minimal therapeutic drug monitoring target concentration required to suppress HIV. CONCLUSIONS: Because, at least in part, of poor drug penetration into the genital tract, an undetectable HIV viral load in the BP does not guarantee an undetectable viral load in semen. In view of this, caution should be taken in concluding that patients on HAART with suppressed viraemia are sexually non-infectious.


Assuntos
Fármacos Anti-HIV/farmacocinética , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV-1/isolamento & purificação , Sêmen/virologia , Carga Viral , Adulto , Idoso , Fármacos Anti-HIV/uso terapêutico , Estudos Transversais , Infecções por HIV/metabolismo , Infecções por HIV/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , RNA Viral/sangue , Sêmen/metabolismo , Distribuição Tecidual , Carga Viral/métodos
5.
Gynecol Obstet Fertil Senol ; 47(4): 330-336, 2019 04.
Artigo em Francês | MEDLINE | ID: mdl-30771515

RESUMO

OBJECTIVE: To evaluate and compare the complications, the rate of revision surgeries and the long-term patient postoperative satisfaction level for the two main indications of labia minora reduction: aesthetic or functional. METHODS: A comparative, retrospective and multicentered study was carried out in Belfort and Montbéliard hospitals between January 2010 and January 2017. Ninety-two primary labia minora reductions for labia minora hypertrophy have been listed. Each patient has been requested to fill in a questionnaire about the main indication of labiaplasty, any potential complication, a revision surgery and her level of the satisfaction. Patients who had agreed to respond were divided into two groups: a "functional indication" group (FI) and an "aesthetic indication" group (AI). RESULTS: Thirty-seven patients (40%) answered the survey: 19 (51%) have been included in the FI group and the remaining 18 (49%) in the AI group. The mean postoperative follow-up duration was 3.2 years. We identified 13 patients (35%) who encountered a postoperative complication. It predominates in the FI group (53% versus 17%, P=0.04). Seven patients (19%) were treated by revision surgeries. All of them belonged to the IF group. Whatever the indication of the labiaplasty, 86% of the patients have been satisfied by the outcomes. CONCLUSION: A labia minora reduction is a highly appreciated surgical treatment on the long term whatever the initial surgical indication. However, postoperative complications and revision surgeries are not negligible especially when the main indication is functional.


Assuntos
Satisfação do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias , Reoperação/estatística & dados numéricos , Vulva/cirurgia , Adolescente , Adulto , Estética , Feminino , Humanos , Hipertrofia , Pessoa de Meia-Idade , Estudos Retrospectivos , Inquéritos e Questionários , Vulva/patologia , Adulto Jovem
6.
PLoS One ; 14(10): e0223969, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31647836

RESUMO

Effects of steady-state rifabutin on the pharmacokinetics of steady-state maraviroc were investigated in fourteen healthy adult female and male volunteers. Maraviroc 300 mg twice daily (BID) was given orally with food for fifteen days. On day six, rifabutin 300 mg once daily (QD, P.O.) was added to the regimen. Formal pharmacokinetic (PK) sampling was performed on days five and fifteen. Individual plasma drug concentration-time data for maraviroc, and rifabutin on day fifteen, were obtained using validated High Performance Liquid Chromatography (HPLC) tandem Mass Spectrometry (MS/MS). Rifabutin steady state exposure was comparable to data in the literature. Maraviroc area under the curve (AUC) and minimum plasma concentration (Clast or Cmin) were reduced by 17% and 30% respectively when co-administered with rifabutin. No unexpected or serious adverse eventsoccurred. Based on the reduced exposure of maraviroc observed in this study, increasing the dose of maraviroc may be studied to normalize its moderately reduced exposure following rifabutin co-administration, a moderate inducer of CYP3A4.


Assuntos
Antibacterianos/farmacocinética , Interações Medicamentosas , Inibidores da Fusão de HIV/farmacocinética , Maraviroc/farmacocinética , Rifabutina/farmacocinética , Adolescente , Adulto , Idoso , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Tecidual , Adulto Jovem
7.
Aquat Toxicol ; 89(2): 129-35, 2008 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-18649952

RESUMO

Long-term exposures to organotin compounds have shown alterations on endogenous steroid levels in gastropods together with the development of imposex. However, information regarding short-term effects of these compounds on the endocrine system of gastropods is lacking. This work aimed at investigating those responses in the ramshorn snail Marisa cornuarietis by looking at both endogenous levels of free and esterified steroids and the metabolism of the androgen precursor androstenedione by digestive gland/gonad microsomal fractions. One-week exposure to the organotin compound triphenyltin (TPT) led to a significant increase in esterified testosterone (60-85%) and a decrease in esterified estradiol (50-84%) in females, but had no effect on males. The observed alterations in esterified steroids were not directly related to changes in P450 aromatase activity that remained unchanged in exposed females. The enzymes involved in the metabolism of the androgen precursor androstenedione, namely 17beta-hydroxysteroid dehydrogenases and 5alpha-reductases, were not significantly altered by TPT exposure, suggesting that such enzymes are not primary targets of TPT in M. cornuarietis. Additional studies are needed to fully understand the significance of the observed alterations in females and their potential relationship with the development of imposex.


Assuntos
Estrogênios/metabolismo , Compostos Orgânicos de Estanho/toxicidade , Caramujos/efeitos dos fármacos , Testosterona/metabolismo , Poluentes Químicos da Água/toxicidade , Androstenodiona/metabolismo , Animais , Aromatase/metabolismo , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/metabolismo , Esterificação , Feminino , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Caramujos/metabolismo , Fatores de Tempo
8.
Clin Pharmacol Ther ; 82(4): 389-95, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17361121

RESUMO

This genotype panel study investigated the effect of ABCB1 polymorphism in exon 26 (C3435T), exon 21 (G2677T/A), and exon 12 (C1236T) on saquinavir pharmacokinetics and on the expression and activity of P-glycoprotein (P-gp) in peripheral blood monocytic cells (PBMCs). One hundred and fifty healthy volunteers were genotyped to identify 15 TT3435 and 15 CC3435 individuals. In these individuals, saquinavir pharmacokinetics were assessed after administration of a single oral dose of saquinavir 1,000 mg and saquinavir/ritonavir 1,000/100 mg. PBMC P-gp expression and activity were assessed in 15 and 19 subjects. The co-administration of ritonavir on study day 2 caused a significant increase in saquinavir exposure, in both TT3435 and CC3435 individuals. No correlation was observed between the ABCB1 C3435T, G2677T/A, and C1236T polymorphisms, separately and in haplotypes, with saquinavir pharmacokinetics, administered with or without ritonavir and with PBMC P-gp expression and activity. In conclusion, ABCB1 polymorphism has no pronounced effect on saquinavir exposure.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Inibidores da Protease de HIV/farmacocinética , Polimorfismo de Nucleotídeo Único , Ritonavir/farmacocinética , Saquinavir/farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Administração Oral , Adulto , Combinação de Medicamentos , Éxons , Genótipo , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/sangue , Haplótipos , Humanos , Leucócitos Mononucleares/metabolismo , Estudos Longitudinais , Fenótipo , RNA Mensageiro/metabolismo , Valores de Referência , Rodamina 123/metabolismo , Ritonavir/administração & dosagem , Ritonavir/sangue , Saquinavir/administração & dosagem , Saquinavir/sangue
9.
Clin Pharmacol Ther ; 81(4): 517-20, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17329994

RESUMO

The recommended dose of lamivudine in children is higher when compared with adults: 4 mg/kg vs approximately 2 mg/kg (150 mg) and administered twice a day. Limited data are available to demonstrate that this increased dose results in adequate exposure to lamivudine in children with human immunodeficiency virus (HIV) infection. Data were selected from children who were using lamivudine for at least 2 weeks before a full pharmacokinetic (PK) study was conducted. Lamivudine PK parameters were significantly related to age. The age of 6 years appeared to be a cutoff for a change in PK parameters of lamivudine, with children <6 years of age (n=17) having a median area under the curve 43% lower and a median peak plasma concentration 47% lower (both P<0.001) than older children (n=34). In conclusion, further investigation of the relationship between decreased lamivudine exposure and treatment outcome and long-term resistance development in younger children with HIV infection is warranted.


Assuntos
Envelhecimento/metabolismo , Fármacos Anti-HIV/farmacocinética , Lamivudina/farmacocinética , Algoritmos , Área Sob a Curva , Peso Corporal/fisiologia , Criança , Pré-Escolar , Feminino , Infecções por HIV/metabolismo , Humanos , Masculino , Caracteres Sexuais
10.
J Steroid Biochem Mol Biol ; 99(2-3): 147-56, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16621518

RESUMO

In a recent study, we demonstrated that androstenedione was mainly converted to testosterone (T) and 5alpha-dihydrotestosterone (DHT) by digestive gland/gonad complex microsomal fractions isolated from male Marisa cornuarietis, whereas it was primarily metabolized to 5alpha-dihydroandrostenedione (DHA) by females. In the present work, the sexual dimorphic metabolism of androstenedione was further investigated, and attributed to a higher 17beta-hydroxysteroid dehydrogenase activity in males than in females. Thereafter, the hypothesis was tested that the metabolism of androstenedione might be affected by exposure to tributyltin (TBT) and triphenyltin (TPT), which are known to induce the development of imposex in several gastropod species. The in vitro metabolism of androstenedione, particularly the formation of DHA and DHT, was inhibited by both compounds. However, in vivo experiments showed no significant alteration in the metabolism of androstenedione in males, but a marginal (TBT) and a significant (TPT) inhibition of the formation of DHA in females exposed for 150 days to concentrations that had significantly induced the development of imposex. The ratio DHT+T/DHA, a possible indicator of metabolic androgenization, tended to increase (0.43 versus 0.35, p=0.06) in TPT exposed females. However, this ratio never reached values comparable to those found in males (11+/-1).


Assuntos
Androstenodiona/metabolismo , Gônadas/efeitos dos fármacos , Compostos Orgânicos de Estanho/farmacologia , Caramujos/efeitos dos fármacos , Androstenodiona/análogos & derivados , Animais , Di-Hidrotestosterona/metabolismo , Relação Dose-Resposta a Droga , Feminino , Gônadas/metabolismo , Cinética , Masculino , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Fatores Sexuais , Caramujos/metabolismo , Testosterona/metabolismo , Fatores de Tempo , Compostos de Trialquitina/farmacologia , Poluentes da Água/farmacologia
12.
Environ Sci Pollut Res Int ; 23(8): 8008-20, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26780042

RESUMO

Genitors of the Pacific oyster Crassostrea gigas were submitted during gametogenesis to a short pulse exposure to the herbicide diuron at a realistic environmental concentration. Histological analysis showed no effect of diuron on gametogenesis course, sex ratio and reproductive effort. A non-significant increase in testosterone and progesterone levels was observed in genitors exposed to the herbicide. At cell level, diuron exposure was shown to modulate the phagocytic activity of circulating hemocytes. The results of a transcriptional analysis showed that diuron affected the expression of genes belonging to functions known to play a major role during oyster gametogenesis such as gene transcription regulation, DNA replication and repair, DNA methylation and cytokinesis. Taking into account the results we previously obtained on the same genitors, this study showed a negative effect of diuron on oyster reproduction by inducing both structural and functional modifications of the DNA.


Assuntos
Crassostrea/efeitos dos fármacos , Diurona/toxicidade , Monitoramento Ambiental/métodos , Gametogênese/efeitos dos fármacos , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Crassostrea/genética , Crassostrea/crescimento & desenvolvimento , Gametogênese/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Hemócitos/efeitos dos fármacos , Reprodução/efeitos dos fármacos
13.
Ann N Y Acad Sci ; 1040: 354-6, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15891060

RESUMO

Marisa cornuarietis (Mollusc), Hyalella azteca (Crustacean), and Paracentrotus lividus (Echinoderm) demonstrated the ability to metabolize androgens through different pathways catalyzed by 5alpha-reductases (5alpha-R), hydroxysteroid dehydrogenases (HSD), hydroxylases, sulfotransferases (SULT), and fatty-acid acyl-CoA acyltransferases (ATAT). Interspecies differences and tissue-specific distribution of those enzymatic activities were observed. Xenobiotics, such as triphenyltin, tributyltin, and fenarimol, interfered with some of the pathways studied, namely, testosterone sulfation, testosterone esterification, and 5alpha-R activity. The work evidenced different sensitivity of those pathways to androgenic compounds, together with interphyla differences in androgen metabolism.


Assuntos
Androgênios/metabolismo , Crustáceos/metabolismo , Equinodermos/metabolismo , Moluscos/metabolismo , Xenobióticos/metabolismo , Animais , Especificidade da Espécie
14.
J Clin Pharmacol ; 45(2): 211-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15647414

RESUMO

Didanosine enteric-coated should be taken on an empty stomach, but the once-daily combination of indinavir/ritonavir can be taken with food. Because these drugs are frequently included in 1 regimen, the food effects on the pharmacokinetics were evaluated. This was a randomized, 4-way crossover study of single doses of didanosine enteric-coated 400 mg and indinavir/ritonavir 1200/400 mg in 8 healthy subjects. The following regimens were given: didanosine enteric-coated 2 hours after breakfast (reference regimen A), indinavir/ritonavir with breakfast (reference regimen B), didanosine enteric-coated + indinavir/ritonavir 2 hours after breakfast (test regimen C), and didanosine enteric-coated + indinavir/ritonavir with breakfast (test regimen D). Breakfast was 550 kcal, 28% fat. Blood samples were drawn before and up to 24 hours after ingestion. Statistical comparisons of test regimens C and D with reference regimens A and B were made using the equivalence approach for indinavir and didanosine area under the curve and C(max) (0.80-1.25). Eight subjects (5 men, 3 women) were enrolled and completed the study. Indinavir area under the curves were bioequivalent in test regimens C and D compared to reference regimen B. A 14% increased C(max) was observed in test regimen C. Didanosine area under the curve in test regimen D was 4% lower and suggestive of bioequivalence compared to reference regimen A. However, test regimen C didanosine area under the curve was 23% lower and bioinequivalent compared to reference regimen A. Didanosine C(max) decreased 42% and 46% in test regimens C and D, respectively, in comparison to reference regimen A. In this study, dosing didanosine enteric-coated 400 mg once daily + indinavir/ritonavir 1200/400 mg once daily with breakfast indicated no decrease in the amount of absorption for either didanosine and indinavir and that this regimen could be administered with food.


Assuntos
Preparações de Ação Retardada , Didanosina/farmacocinética , Interações Medicamentosas , Indinavir/farmacocinética , Ritonavir/farmacocinética , Administração Oral , Adulto , Área Sob a Curva , Cápsulas , Estudos Cross-Over , Didanosina/administração & dosagem , Didanosina/metabolismo , Esquema de Medicação , Quimioterapia Combinada , Feminino , Interações Alimento-Droga , Meia-Vida , Voluntários Saudáveis , Humanos , Indinavir/administração & dosagem , Indinavir/farmacologia , Masculino , Reprodutibilidade dos Testes , Ritonavir/administração & dosagem , Ritonavir/farmacologia , Equivalência Terapêutica
15.
Aquat Toxicol ; 74(1): 92-5, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15963577

RESUMO

Two sulfatase isoforms, a soluble one with an optimum pH of 5.0, and a microsomal one with an optimum pH of 7.6, were observed in digestive gland, gonads, mantle and gills of the oyster C. virginica. The highest sulfatase activity was recorded in the digestive gland cytosol and is likely to interfere with the in vitro determination of sulfotransferase activity. Indeed, the sulfatase inhibitor Na(2)SO(3) led to an increase of measured sulfotransferase activity (31+/-9%), suggesting that those sulfatases might be partially responsible for the low sulfotransferase activities found in C. virginica.


Assuntos
Ostreidae/enzimologia , Sulfatases/análise , Animais , Concentração de Íons de Hidrogênio , Isoenzimas/análise , Sulfatases/antagonistas & inibidores , Sulfitos/farmacologia , Sulfotransferases/metabolismo , Trítio
16.
Aquat Toxicol ; 71(3): 273-82, 2005 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-15670633

RESUMO

Testosterone conjugation activities, microsomal acyltransferases and cytosolic sulfotransferases, were investigated in three invertebrate species, the gastropod Marisa cornuarietis, the amphipod Hyalella azteca, and the echinoderm Paracentrotus lividus. The goals of the study were to characterize steroid conjugation pathways in different invertebrate phyla and to assess the susceptibility of those processes to disruption by environmental chemicals. All three species exhibited palmitoyl-CoA: testosterone acyltransferase activity (ATAT) in the range of 100-510 pmol/min/mg protein. Despite similarities in specific activities, kinetic studies indicated that ATAT had a higher affinity for testosterone but a lower V(max) in M. cornuarietis than in P. lividus, and intermediate values were found for H. azteca. In contrast, the activity of testosterone sulfotransferase (SULT) was rather low (0.05-0.18 pmol/min/mg protein) in M. cornuarietis and H. azteca. The low activity precluded kinetic analyses and inhibition studies with these species. P. lividus digestive tube displayed high SULT activity (50-170 pmol/min/mg protein) at moderate testosterone concentrations, but was inhibited at high testosterone concentrations. The interference of model pollutants (triphenyltin (TPT), tributyltin (TBT), and fenarimol) with these conjugation pathways was investigated in vitro. Both TPT and TBT (100 microM) inhibited ATAT in P. lividus (68 and 42% inhibition, respectively), and appeared to act as non-competitive inhibitors. ATAT activity in M. cornuarietis was less affected by organotins, and a significant inhibition (20% inhibition) was detected only with TBT. Fenarimol (100 microM) did not affect ATAT in any of the species tested. Sulfation of testosterone was suppressed by the organotins as well as fenarimol when using cytosolic preparations from P. lividus. These results demonstrated the existence of interphyla differences in testosterone conjugation, and revealed that these processes can serve as targets for endocrine disrupting chemicals.


Assuntos
Aciltransferases/metabolismo , Invertebrados/efeitos dos fármacos , Palmitoil Coenzima A/metabolismo , Sulfotransferases/metabolismo , Testosterona/metabolismo , Poluentes Químicos da Água/toxicidade , Análise de Variância , Animais , Citosol/metabolismo , Invertebrados/enzimologia , Itália , Cinética , Microssomos/metabolismo , Compostos Orgânicos de Estanho/toxicidade , Pirimidinas/toxicidade , Água do Mar , Especificidade da Espécie , Compostos de Trialquitina/toxicidade
17.
Aquat Toxicol ; 74(1): 3-19, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15916818

RESUMO

Caddisfly larvae of Hydropsyche exocellata were sampled from seven locations receiving increasing levels of urban and industrial waste water discharges along the Llobregat river system (NE Spain) during spring and summer 2003. Locations were selected to include aquatic communities in poor and good ecological state according to measured physicochemical water parameters and the analysis of benthic macroinvertebtrate communities. Whole body residues of selected metals (Fe, Al, Zn, Cu, Co, Ni, Pb, Cd) were determined in conjunction with antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase activity of GST, GSTPX), a phase II enzyme (glutathione-S-transferase, GST) and lipid peroxide levels measured as thiobarbituric reactive species (TBARs) with the aim of investigating whether resident macroinvertebrate benthic species were responsive to changes in water quality. Caddisfly larvae inhabiting those rivers were exposed to increasing levels of metal pollution. Enhanced activities of two (CAT and GST) out of the four tested enzymes, coupled with increased levels of TBARs, indicated increasing levels of stress in the studied species towards downstream reaches or locations near industrial and urban areas. These results indicate that combination of chemical and biochemical responses can be used to assess and diagnose pollution in high stressed river ecosystems.


Assuntos
Monitoramento Ambiental , Insetos , Metais Pesados/análise , Estresse Oxidativo/fisiologia , Poluição Química da Água , Animais , Catalase/metabolismo , Água Doce , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Larva/química , Larva/enzimologia , Larva/fisiologia , Peróxidos Lipídicos/metabolismo , Espanha , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico
18.
Biomaterials ; 24(4): 689-96, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12437963

RESUMO

Water-in-fluorocarbon reverse emulsions and microemulsions stabilized by semi-fluorinated amphiphiles derived from the dimorpholinophosphate polar head group, C(n)F(2n+1)(CH(2))(m)OP(O)[N(CH(2)CH(2))(2)O](2) (FnHmDMP), are being investigated as new delivery systems for drugs or genetic materials into the lung. Since information related to the toxicity of fluorinated surfactants is still very limited, we evaluated herein the cytotoxicity of a series of FnHmDMP (n=4, 6, 8 and 10 and m=2, 5, and 11). Both solutions of FnHmDMP in fluorocarbons, and reverse water-in-fluorocarbon emulsions stabilized by FnHmDMP were assessed in order to determine the relation between surfactant structure and cell toxicity, and select the most innocuous emulsifier. A first short-term evaluation on mouse fibroblasts using a viability/cytotoxicity assay indicated that amphiphiles (in solution) with a chain length longer than C12 exhibit less toxicity than amphiphiles with shorter chain. Moreover cytotoxicity decreased also with length of the fluorinated segment. The protective effect of the fluorinated chain was strongly supported by the fact that the hydrogenated analog, C(15)H(31)OP(O)[N(CH(2)CH(2))(2)O](2) (H15DMP), was highly toxic. Qualitative evaluation on human lung epithelial cells (HLEC) using a colorimetric method (Mayer's hematoxylin) confirmed that amphiphiles (in solution) with longer chain were the least cytotoxic. The protective effect of the fluorinated chain appeared, however, to be significant only at low amphiphile concentrations (0.1% w/v). In contrast, at higher concentrations (1% and 5% w/v), the total chain length was the determining factor. Quantitative evaluation of the least cytotoxic amphiphiles using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method then showed that F10H11DMP (in solution) was harmless until its solubility limit (1% w/v); cell growth was even enhanced due to improved oxygenation provided by the fluorocarbon phase. F8H11DMP exhibited some cytotoxicity at both 1% and 5% w/v, but the toxicity appeared to level off with concentration. Reverse water-in-perfluorooctyl bromide (PFOB) emulsions stabilized by either F10H11DMP or F8H11DMP were found to be non-cytotoxic. In conclusion, the present evaluation indicates that the cytotoxicity of FnHmDMP depends on both total and fluorinated amphiphile chain length, and leads us to select F8H11DMP and F10H11DMP as the less cytotoxic amphiphiles among a series of FnHmDMP compounds. Furthermore, water-in-fluorocarbon emulsions stabilized with F8H11DMP and F10H11DMP appeared to be non-cytotoxic towards HLEC in culture.


Assuntos
Fluorocarbonos/toxicidade , Morfolinas/química , Fosfatos/química , Tensoativos/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fluorocarbonos/química , Fluorocarbonos/metabolismo , Humanos , Camundongos , Tensoativos/química , Tensoativos/metabolismo , Água/química
19.
J Neurosurg ; 63(6): 965-9, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4056911

RESUMO

The case is presented of a 59-year-old man with cerebral amyloid angiopathy and three consecutive hemorrhages in the occipital lobes. The clinicopathological features and the relationship to Alzheimer's dementia are discussed. The correct treatment of intracerebral hemorrhage related to cerebral amyloid angiopathy is a matter of controversy.


Assuntos
Amiloidose/complicações , Encefalopatias/complicações , Hemorragia Cerebral/etiologia , Amiloidose/diagnóstico , Encéfalo/irrigação sanguínea , Encefalopatias/diagnóstico , Hemorragia Cerebral/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Neurosurg ; 60(4): 848-9, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6707755

RESUMO

A case of familial oligodendroglioma, occurring in a mother and her daughter, is presented.


Assuntos
Neoplasias Encefálicas/genética , Oligodendroglioma/genética , Adulto , Feminino , Humanos
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