RESUMO
An association between favism (a hemolytic reaction to consumption of fava beans), glucose-6-phosphate dehydrogenase deficiency (G6PD(-)) and acid phosphatase locus 1 (ACP(1)) phenotypes has been reported; the frequency of carriers of the p(a) and p(c) ACP(1) alleles was found to be significantly higher in G6PD(-) individuals showing favism than in the general population. Here, we investigated the hypothesis that favism is caused by toxic Vicia faba substances, which in some ACP(1) phenotypes cause increased phosphorylation and consequently increased glycolysis, with strong reduction in reduced glutathione production, resulting in hemolysis. It has been demonstrated that ACP(1) f isoforms have physiological functions different from those of s isoforms and are responsible for most of the phosphatase activity, in addition to being less stable in the presence of oxidizing molecules. Thus, the C, CA and A phenotypes, characterized by lower concentrations of f isoforms, could be more susceptible to damage by oxidative events compared to the other phenotypes. To test this hypothesis, the (f+s) enzymatic activity of different ACP(1) phenotypes with and without added V. faba extract was analyzed. Enzymatic activities of ACP(1) A, -CA, -C groups (low activity) and -B, -BA, -CB groups (high activity) were significantly different after addition of V. faba extract. Phenotypes A, CA and C had extremely low enzymatic activity levels, which would lead to low levels of reduced glutathione and bring about erythrocyte lysis.
Assuntos
Favismo/genética , Polimorfismo Genético , Proteínas Tirosina Fosfatases/genética , Proteínas Proto-Oncogênicas/genética , Favismo/enzimologia , Deficiência de Glucosefosfato Desidrogenase/genética , HumanosRESUMO
Melamine is used in the synthesis of resins used for the manufacture of laminates, plastics and coatings, including materials in contact with food such as crockery. A method for the assessment of melamine by GC-MSMS in urine samples was developed and tested in 100 non-occupationally exposed subjects: 63 females (14-66) and 37 males (15-65). The LOD and LOQ were 4 microg/l and 13.4 microg/l respectively. Results showed traces of melamine in the urines of 21% of subjects monitored (10-29.7 microg/l). Presence of melamine and time since last meal at sampling were inversely related (p = 0.021). In addition a significant correlation (p = 0.00) between the presence of the substance in urines and the use of melamine dishes was shown.
Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Triazinas/urina , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto JovemRESUMO
The purpose of this work is to compare the PCB values in blood, serum and adipose tissue of non-exposed people over the last twenty years of scientific literature in order to establish whether the determination of single congeners is better then the evaluation of the total PCB amount moreover an analytical strategy useful to define a reference value for non-exposed Italian population has been evaluated. In the literature very variable results were found for the determination of total PCBs in blood, in serum or adipose tissue. We suggest to determine only the amount of the most toxic congeners of PCBs (28, 52, 77, 101, 118, 126, 138, 153, 169, 180) by using the HRGC/ECD as analytical technique.
Assuntos
Bifenilos Policlorados/análise , Humanos , Itália , Bifenilos Policlorados/metabolismo , Valores de ReferênciaRESUMO
The aim of this work is to determine the amount of some aromatic amines in urine of non-exposed people in order to define a reference value. The literature examination has showed that only a small numbers of aromatic amines are usually determined in urine namely: aniline, benzidine, 2-naphtilamine, o-toluidine, 3,3'-dichlorobenzidine, 4-chloro-o-toluidine and 4-chlorobenzidine. On the basis of our experience the analytical method proposed by Lichtenstein is appropriate for obtaining reliable analytical results.
Assuntos
Aminas/urina , Carcinógenos/análise , Hidrocarbonetos Aromáticos/urina , Humanos , Valores de ReferênciaRESUMO
The interlaboratory validation of analytical procedures for the assay of urinary 3,5,6-trichloro-2-pyridinol (TCP) in the general Italian population is reported. The determinations were performed by high-resolution gas chromatography (HRGS) with electron capture detection and HRGS with mass spectrometry (MS) in 2 laboratories. The urine samples were from 42 participants from 3 regions of Italy. The results were evaluated by interlaboratory quality control. Urinary TCP concentrations were above the detection limit (1.2 micrograms/L) in 88% of the population, with a mean detectable concentration [GM (GSD)] of 2.8 (1.9) micrograms/g creatinine (creat). (GM, geometric mean; GSD, geometric standard deviation.) The Mann-Whitney U test showed that wine consumption was a statistically significant variable (p < 0.05) for urinary concentrations of TCP. Analysis of variance of the logarithm of urinary TCP versus wine consumption and diet showed a statistically significant fit. The model used explained 30% of the total variance: wine consumption and diet accounted for 37 and 17% respectively of the explained variance.
Assuntos
Cromatografia Gasosa/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Inseticidas/urina , Piridonas/urina , Adulto , Animais , Clorpirifos/farmacocinética , Cromatografia Líquida de Alta Pressão , Dieta , Feminino , Meia-Vida , Humanos , Hidrólise , Inseticidas/farmacocinética , Itália , Masculino , Pessoa de Meia-Idade , Resíduos de Praguicidas/urina , Controle de Qualidade , Valores de Referência , VinhoRESUMO
Urinary excretion of ethylenethiourea (ETU) was monitored for 8 days in a group of five male non-smoker volunteers on a diet, the items of which were assayed for ETU and carbon sulphide. Urinary excretion of ETU reflected the consumption of wine, fruit and vegetables. Urinary ETU concentrations ranged from 0.6 to 6.7 micrograms/g creatinine. ETU concentrations in the food eaten by the volunteers were generally below the detection limit whereas in wine 8.8 micrograms/l ETU was detected. Evolution of carbon sulphide by food samples ranged from 0.03 to 0.17 mg/kg. Mean (+/- S.D.) daily intake of ETU in wine was 3.5 +/- 0.2% of the acceptable daily intake (ADI): 0.070 +/- 0.004 micrograms/kg body wt. During the 8 days of the study, an average of 48.3% of the ETU ingested in wine was excreted unmodified by the kidneys. Twenty-four hour urinary excretion of ETU was significantly correlated with daily intake of ETU (r = 0.768) and CS2 evolved by the daily food items (r = 0.414).