Rapid multi-residue method for the determination of pesticide residues in human serum

Exposure to pesticides can represent a potential risk to humans. Agricultural workers are at risk of chronic toxicity. Hence, the evaluation of pesticide residues in their blood gives an indication about the extent of exposure and help in assessing adverse health effects. The aim of our study was to develop analytical method for the simultaneous determination of some residues of pesticides using gas chromatography-mass spectrometry (GC-MS). This method involves a liquid-liquid extraction procedure. Pesticide residues were separated and detected using GC-MS, and acquisition was performed in the sellected ion monitoring (SIM) mode. For most of the pesticides, average recoveries ranged between 65 and 101% at three different fortification levels. The linearity of the method was satisfactory in the range of 5 to 50 ng/ml, with a correlation coefficient between 0.998 and 0.999, depending on the analyte. The estimated limit of detection and limit of quantification ranged from 2 to 5 ng/ml and from 5 to 10 ng/ml, respectively. The method precision and accuracy were found to be satisfactory at three concentration levels. The variation coefficients of intra-day and inter-day precision ranged from 0.4 to 14% and from 2.5 to 15%, respectively for most studied pesticides.Keywords: Analytical methods, human serum, GC-MS, pesticide residues, validatio

Infantile Scurvy: Two Case Reports

Background. Ascorbic acid (vitamin C) is necessary for the formation of collagen, reducing free radicals, and aiding in iron absorption. SCURVY, a disease of dietary ascorbic acid deficiency, is uncommon today. It still exists in high risk groups including economically disadvantaged populations with poor nutrition. The incidence of SCURVY in the pediatric population is very low. Cases Report. Here we report two cases of SCURVY revealed by subperiosteal hematoma in children with cerebral palsy and developmental delay. Conclusion. SCURVY is extremely rare in children. Musculoskeletal manifestations are prominent in pediatric SCURVY. Multiple subperiosteal hematomas are an important indicator for diagnosis

Évaluation d’une méthode de dosage de la clozapine par spectrophotométrie UV

La clozapine, principal neuroleptique indiqué dans le traitement de la schizophrénie résistante, est à l’origine de nombreux cas d’intoxications accidentelles ou volontaires, d’où l’intérêt de son dosage. Notre travail a pour objectif la mise au point d’une méthode de dosage permettant le diagnostic d’une intoxication par la clozapine. La méthode est basée sur la lecture de l’absorbance, à 365 nm, du produit de la réaction entre la clozapine et l’iode dans le dichlorométhane. Les résultats ont montré que cette méthode de dosage est linéaire de 15 à 400 mg/L (r = 0,995), avec une limite de détection de 10,42 mg/L. La précision et l’exactitude ont été meilleures dans la zone de 120 à 400 mg/L. Le rendement de l’extraction, par l’éther, à partir des urines est en moyenne de 77,7 %. Cette méthode permet le dosage de la clozapine dans les urines, les comprimés et dans les échantillons post mortem en cas d’intoxication mortelle à la clozapine

Kidney Stones in Children and Teenagers in the Central Coast Region of Tunisia

Objective: Since 1980s, the clinical and biological characteristics of urolithiasis in Tunisian children have continuously evolved. This retrospective study defines the current status of urolithiasis among children and adolescents in Tunisia. Methods: We retrospectively reviewed the records of 310 children and adolescents (age: 3 months - 19 years) between 2003 and 2010, holding urolithiasis. A first-line metabolic, urine and plasma work-up was performed in all patients. Physical and chemical analysis of the stones was performed respectively by stereomicroscopy and infrared spectroscopy. Statistical analysis of the results was performed with SPSS 11.0 software. The Chisquare test was used for comparison of percentages. Findings: Our study shows a male predominance of urolithiasis with a sex ratio of 1.5. Stones were located in the upper urinary tract in 70.7% of cases. Calcium oxalate was the predominant constituent in 52.6% of stones. There was an increasing prevalence of calcium oxalate stones according to age in both genders (48.6% in infants vs 68.5% in teenagers (P<0.01)). Struvite was more frequent in patients aged 2-9 years (P<0.02) and significantly more prevalent in boys than in girls (P<0.001). Ammonium urate stones were observed in 14.2% and were more frequent in infants. Conclusion: Our results emphasize a high percentage of calcium oxalate stones and a low percentage of struvite stones. The persistence of urate stones reflects the particular eating habits and the infectious risk factors. The patient’s age is an important factor that must be taken into account during etiopathogenic workup

Interaction Effects of the Leu162Val PPAR α

Leu162Val PPARα and Pro12Ala PPARγ2 were investigated for their individual and their interactive impact on MS and renal functionality (RF). 522 subjects were investigated for biochemical and anthropometric measurements. The diagnosis of MS was based on the IDF definition (2009). The HOMA 2 was used to determine HOMA-β, HOMA-S and HOMA-IR from FPG and FPI concentrations. RF was assessed by estimating the GFR. PCR-RFLP was performed for DNA genotyping. Allele frequencies were 0.845 for Pro and 0.155 for Ala, and were 0.915 for Leu and 0.085 for Val. We showed that carriers of the PPARα Val 162 allele had lower urea, UA and higher GFR compared to those homozygous for the Leu162 allele. Subjects carried by PPARγ2Ala allele had similar results. They also had reduced FPG, FPI and HOMA-IR, and elevated HOMA-β and HOMA-S compared to those homozygous for the Pro allele. Subjects were divided into 4 groups according to the combinations of genetic alleles of the 2 polymorphisms. Subjects carrying the Leu/Val with an Ala allele had lower FPG, PPI, HOMA-IR, urea, UA levels, higher HOMA-β, HOMA-S and GFR than different genotype combinations. Leu162Val PPARα and Pro12Ala PPARγ2 can interact with each other to modulate glucose and insulin homeostasis and expand their association with overall better RF