Antibody response for L1, E6 and E7 HPV 16 and HPV 18 antigens in Tunisian women with cervical cancer and controls

Results obtained in the present work indicated that the Luminex assay is more sensitive than ELISA. The reactivity to the early antigens E6 and E7 was 37% versus 42% for HPV 16 and 21% versus 20% for HPV 18 among cervical cancer cases using ELISA. However, these ratios were 44% and 61%, respectively, for E6 and E7 HPV 16 versus 28% and 21% for E6 and E7 HPV 18 when using the Luminex technique. Data also indicated that HPV 16 and HPV 18 showed distinct profiles for the different antigens tested. Finally, the differences in antibody responses between cervical cancer cases and benign cases toward the different antigens were significant.     

Induction and reversibility of thyroid proliferative changes in suckling rats given thiocyanate

Potassium thiocyanate given in the drinking water of pregnant rats led to decreased body weight in their 14-day-old offspring (27%) without altering thyroid weight. Reduction of the suckling rat's body weight could be explained be defective thyroxinemia (38). Plasma FT3 and TSH were unchanged after thiocyanate treatment. The biochemical changes were in agreement with the histological aspects of the hypothyroid animals. The typical pattern was hyperplastic goiter. Colloid volume was reduced compared with controls. Presence of resorbed peripheral vacuoles, a sign of thyroid hyperactivity, was disclosed by a three-fold increase in radioiodide (131I) uptake compared with controls. When the antithyroid drug was removed from the mother's milk, the pups'weight increased but did not reach control values. Plasma thyroid hormone levels returned to normal and even exceeded control values in spite of partial recovery of thyroid iodine content when thiocyanate treatment was stopped for ten days.     

Association of methylenetetrahydrofolate reductase polymorphisms with susceptibility to Alzheimer's disease

Background

Genetic risk factors play an important role in the pathogenesis of Alzheimer's disease (AD). In this case-control study, we examined the C677T and A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and their correlation with this pathology.

Objective

To verify the association between MTHFR C677T and A1298C polymorphisms and Alzheimer's disease.

Method

This work was conducted as a case–control study. Cases consisted of thirty-eight patients and 100 individuals without dementia constituted the control group. Genotyping of MTHFR polymorphisms was performed on patients and controls.

Result

Genetic analyses did not indicate a significant association between the MTHFR C677T mutation and AD (C/T: 63.15% versus 39%, p = 0.087). However, the genotype prevalence of the missense variant MTHFR A1298C was significantly different between patients and controls (A/C: 55% versus 7%, p < 10⁻³). Our data suggest an association between the MTHFR A1298C mutation and AD; however, the MTHFR C677T mutation did not contribute to susceptibility for AD.

Conclusion

The MTHFR A1298C polymorphism is a possible risk factor for Alzheimer's disease.     

Antioxidant effect of vitamin E and selenium on hepatotoxicity induced by dimethoate in female adult rats

Acute exposure to pesticides can cause hepatotoxicity. Our study pertains to the potential ability of selenium and/or vitamin E, used as nutritional supplements, to alleviate oxidative stress induced by dimethoate. Female Wistar rats were randomly divided into seven groups of six each: group I served as controls; group II received in their drinking water dimethoate (2 g L⁻¹); group III received both dimethoate and selenium (0.5 mg/kg of diet); group IV was treated with dimethoate and vitamin E (100 mg/kg of diet); group V received dimethoate+selenium+vitamin E and groups VI and VII received either selenium or vitamin E. The exposure of rats to dimethoate for 30 days promoted oxidative stress with an increase in malondialdehyde and a decrease in glutathione and non-protein thiol levels. A decrease in glutathione peroxidase, superoxide dismutase and catalase activities was also observed. While, plasma transaminases, lactate dehydrogenase activities and bilirubin levels increased. Co-administration of selenium and/or vitamin E through diet improved the biochemical parameters cited above. Liver histological studies confirmed biochemical parameters and the beneficial roles of selenium and vitamin E.     

Some biological effects of scorpion envenomation in late pregnant rats

Scorpion envenoming is less studied during gestation; however, it may induce various biological disturbances in maternal organism and hypothetical ones on their fetuses. The scope of this report was to elucidate some biological effects of such poisoning in late pregnant rats. Hence, TBARS levels in maternal lung, placental and fetal pulmonary and hepatic tissues and dam's biochemical blood parameters (glucose, creatinine, 17-β estradiol, progesterone, blood nitrogen urea, sodium and potassium maternal plasma concentrations) had been evaluated after saline (G1), and scorpion venom (G2: 30 min and G3: 60 min) injections in 22nd day pregnant rats. Histological microscopic examination of these tissues was also carried out in HE-stained paraffin sections. In addition, the mean arterial blood pressure following the envenomation variations was measured in three rats from the same pool. Our results showed that Buthus occitanus tunetanus crude venom induced significant increase in maternal, placental and fetal tissues lipid peroxidation, concomitant with blood pressure elevation. Maternal plasma creatinine, estradiol and progesterone concentrations levelled up significantly after 30 min or later (60 min) after the venom injection. Except for a probable pronounced oedema and few congestions in maternal lungs and degenerative aspects of trophoblast cells, all examined tissues showed a conserved structure. These results suggest that scorpion envenomation may induce gestation process disturbances and threatens both mother's and fetus’ well-being.     

Protective effects of selenium on methimazole-induced anemia and oxidative stress in adult rats and their offspring

The present study investigates the potential ability of selenium, considered as an antioxidant with pharmacological property to alleviate oxidative stress and hematological parameter disorders induced by methimazole, an antithyroid drug. Pregnant Wistar rats were randomly divided into four groups of six each: group I served as negative control and received a standard diet; group II received 250 mg/L of methimazole in drinking water and a standard diet; group III received both methimazole (250 mg/L, orally) and selenium (0.5 mg/kg of diet) supplemented to the standard diet; group IV served as positive control and received a supplement of selenium in the diet (0.5 mg/kg of diet) as sodium selenite (Na(2)SeO(3)). Treatment was started from the 14th day of pregnancy until day 14 after delivery. Methimazole reduced the number of red blood cells, hemoglobin concentration and hematocrit in mothers and their pups. Besides, plasma iron, vitamins B(9), B(12), C and E levels were reduced. Lipid peroxidation increased, objectified by high malondialdehyde levels and lactate dehydrogenase activity in plasma, while glutathione, glutathione peroxidase, superoxide dismutase and catalase activities showed a significant decline. Co-administration of selenium through diet improved all the parameters cited above. It can be concluded that the administration of selenium alleviates methimazole-induced toxicity, thus demonstrating its antioxidant efficacy.     

Serological study in Tunisian cervical cancer patients

Objective

The aim of this study is to use a novel ELISA, based on five recombinant HPV-16 and HPV-18 proteins, for detection HPV-specific antibodies in a case-control study.

Patients and methods

L1, E6 and E7 genes have been over expressed in Escherichia coli as double fused proteins. These recombinant proteins were used in a GST-capture ELISA as coating antigens. Human sera were collected from women with cervical cancer. Negative human sera were collected from patients apparently healthy and may be affected by other infectious agents.

Results

Most of the sera showed a positive reactivity to at least one of the HPV-16 or HPV-18 proteins (52/71). A percentage of 39.50% of the sera from HPV-16 infected women and 21.12% of the sera from women infected by HPV-18 genotype recognised at least one of the HPV-16 or HPV-18 proteins. Sera showed different reactivity to L1, E6 and E7 antigens, and only a few serum samples reacted to L1, E6 and E7 HPV-16, E6 and E7 HPV-18 (co-infection). Differences of reactivity between cases and controls were significant (P < 0.0001).

Conclusion

This novel ELISA, based on recombinant HPV-16 and HPV-18 antigens, is able to detect antibodies in women infected by HPV genotypes. The assay is easy to perform and has low cost, making it suitable for monitoring the natural history of HPV infections as well as for detecting pre-existing HPV antibodies in women who receive vaccination.     

Factitious increases in serum testosterone concentrations related to phenylbutazone therapy

We report 6 additional observations of a drug/hormone assay interaction between serum testosterone and phenylbutazone intake. This interaction had been described previously only once. We discuss its potential mechanisms, based upon our experimental findings, and its clinical implications.