Immunohistochemical analysis of vascular endothelial growth factor (VEGF) and p53 expression in pterygium from Tunisian patients.

A pterygium is characterized by abnormal fibrovascular corneoconjunctival tissue. A number of investigations have attempted to elucidate this incompletely understood pathology. Since vascular endothelial growth factor (VEGF) and p53 are known to participate in tumor vascularization, our purpose was to study VEGF and p53 expression in active primary and recurrent pterygium from Tunisian patients. To this end, 15 cases of active primary pterygium and five cases of recurrent pterygium from Tunisia were studied by immunohistochemistry. Antibodies raised against VEGF and p53 were used to analyze the distribution and expression of these markers in pterygium and normal human conjunctiva were used as negative control. VEGF and p53 proteins were found in all cases of primary pterygium in epithelial, fibroblast and vascular endothelial cells. Active primary and recurrent pterygium have different patterns of expression. In primary pterygium, an important variability of p53 and VEGF expression was observed. However, in recurrent pterygium, p53 immunoreactivity was weak to moderate, whereas VEGF immunoreactivity was strong. In normal human conjunctiva, VEGF and p53 expression was weak to negative. The overexpression of VEGF in active primary and recurrent pterygium suggests that angiogenesis may play a role in pterygium pathogenesis and the expression of p53 in active primary pterygium, which might be associated with its mutated form, supports the hypothesis that actinic radiation may be involved in the genesis of pterygium. Thus, VEGF and p53 may be useful biomarkers for understanding the physiopathology of pterygium.

Immunohistochemical analysis of cellular adhesion molecules (ICAM-1, VCAM-1) and VEGF in fibrovascular membranes of patients with proliferative diabetic retinopathy: preliminary study.

PURPOSE: Diabetic fibrovascular membranes are the main pathological changes of proliferative diabetic retinopathy that can cause serious complications leading to blindness. Since the mechanism of fibrovascular membrane development is still unknown, the aim of our study was to identify potential biomarkers for this pathology. To this end, we analyzed the simultaneous expression of ICAM-1, VCAM-1 and VEGF within tissues of diabetic fibrovascular membranes. PATIENTS AND METHODS: Fibrovascular membranes were taken from nine diabetic patients with proliferative diabetic retinopathy. The fibrovascular membrane specimens were analyzed by immunohistochemistry to determine ICAM-1, VCAM-1 and VEGF expression. Controls were collected on nine normal conjunctivas removed during senile cataract surgery. RESULTS: Coexpression of ICAM-1, VCAM-1 and VEGF was found in most of the diabetic fibrovascular membranes studied. Thus, ICAM-1 was positive in eight of nine membranes (82%), VCAM-1 in seven of nine membranes (78%) and VEGF in all the membranes. CONCLUSIONS: The substantial overexpression of adhesion molecules ICAM-1, VCAM-1 and of VEGF suggests that these molecules might contribute to the development of fibrovascular membranes in patients with proliferative diabetic retinopathy, and that they could constitute suitable markers of this pathology.

Effect of pterygium surgery on corneal topography.

PURPOSE: To evaluate the effect of successful pterygium surgery on corneal topography. METHODS: Computerized corneal topography was performed on 20 eyes with pterygium before and 3 months after successful excision and limbo-conjunctival autograft surgery. Corneal shape, corneal spherical power, simulated keratometric astigmatism, surface regularity index (SRI), and surface asymmetry index (SAI) were assessed before and after surgery. Pre- and postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and manifest refraction spherical equivalent (MRSE) were also evaluated. RESULTS: Changes in corneal shape were mainly a decrease in midline corneal flattening. Corneal spherical power was 41.65+/-3.29 diopters (D) (mean +/- SD) preoperatively and 44.58+/-1.55 D postoperatively (p=0.04). Simulated keratometric astigmatism was 5.47+/-3.45 D preoperatively and 1.79+/-1.52 D postoperatively (p=0.0005). SRI was 1.39+/-0.93 preoperatively and 1.10+/-0.57 postoperatively (p=0.03). SAI was 1.17+/-1.09 preoperatively and 0.75+/-0.73 postoperatively (p=0.02). UCVA was 0.31+/-0.33 preoperatively and 0.52+/-0.32 postoperatively (p=0.04). BSCVA was 0.73+/-0.20 preoperatively and 0.89+/-0.16 postoperatively (p=0.008). MRSE was -0.54+/-3.29 D preoperatively and -1.30+/-3.05 D postoperatively (p=0.45). CONCLUSIONS: Corneal topographic changes caused by the pterygium are almost reversible after surgical treatment. Successful pterygium surgery significantly reduces topographic astigmatism, SRI, SAI, and corneal flattening. However, precise prediction of these refractive changes is not always accurate.

Effect of GSM-900 and -1800 signals on the skin of hairless rats. I: 2-hour acute exposures.

PURPOSE: The acute influence on the skin of non-ionizing electromagnetic fields in the radiofrequency (RF) range used in mobile telephony has not been widely studied to date. The purpose of this work was to determine whether the cells of hairless rat skin are affected by acute local exposure to Global System for Mobile Communication: GSM-900 or -1800 RadioFrequency Radiation (RFR). MATERIALS AND METHODS: Hairless female rats were exposed or sham-exposed for 2 h to GSM-900 or -1800 signals, using a loop-antenna located on the right part of the rats' back. The local Specific Absorption rate (SAR) at skin level was ca. 5 W/kg (5.8+/-0.4 and 4.8+/-0.4 W/kg at 900 and 1800 MHz, respectively). A skin biopsy was done at the end of the experiment not only at the location of exposure, but also on the symmetrical part of the back. RESULTS: Analysis of skin sections using Hematoxylin Eosin Saffron (HES) coloration showed no difference in skin thickness or apparent cell toxicity (with no sign of cellular necrosis) among the animal groups. Histological analysis of the epidermis showed that the ratio between cells expressing the antigen Ki-67 (cellular proliferation marker) and the total number of cells remained within the range of normal proliferation ratio for the exposed side of the animal. No Ki-67 labelling was observed at the dermis level. Results on filaggrin, collagen and elastin levels also showed an insignificant influence of RFR. CONCLUSIONS: These results do not demonstrate any major physical and histological variations at skin level induced by RFR used in mobile telephony.

Effect of GSM-900 and -1800 signals on the skin of hairless rats. II: 12-week chronic exposures.

PURPOSE: The purpose of this work was to determine whether the cellular components of Hairless-rat skin are affected by a chronic local exposure to non-ionizing radiations of Global Mobile Phone System: GSM-900 or -1800 radiations at specific absorption rate (SAR) 2.5 and 5 W/kg. MATERIALS AND METHODS: A selected part of the right back of five-week old female hairless rats was exposed or sham exposed (n = 8) for 2 h per day, 5 days a week, for 12 weeks to GSM-900 or -1800 signals using a loop-antenna. At the end of the experiment, skin biopsies were taken. RESULTS: Analyses of skin sections using hematoxylin eosin saffron (HES) coloration showed no significant difference in skin thickness among the groups. Immunohistochemical analysis of basal lamella cells in radiofrequency radiation (RFR)-exposed epidermis showed that the ratio of the antigen Ki-67 (cellular proliferation marker) positive cells to total lamella cells remained within the range of the normal proliferation ratio. No significant differences in the level of filaggrin, collagen, and elastin were observed among the different groups. CONCLUSIONS: The results of this 12-week chronic study do not demonstrate major histological variations in the skin of hairless rats exposed to RFR used in mobile telephony (GSM-900 or -1800).

Measurement of DNA damage after acute exposure to pulsed-wave 2450 MHz microwaves in rat brain cells by two alkaline comet assay methods.

PURPOSE: To investigate the effect of 2450 MHz pulsed-wave microwaves on the induction of DNA damage in brain cells of exposed rats and to discover whether proteinase K is needed to detect DNA damage in the brain cells of rats exposed to 2450 MHz microwaves. MATERIALS AND METHODS: Sprague-Dawley rats were exposed to 2450 MHz pulsed-wave microwaves and sacrificed 4 h after a 2-h exposure. Rats irradiated whole-body with 1 Gy (137)Cs were included as positive controls. DNA damage was assayed by two variants of the alkaline comet assay on separate aliquots of the same cell preparation. RESULTS: Significant DNA damage was observed in the rat brain cells of rats exposed to gamma-rays using both versions of the alkaline comet assay independent of the presence or absence of proteinase K. However, neither version of the assay could detect any difference in comet length and/or normalized comet moment between sham- and 2450 MHz pulsed-wave microwave-exposed rats, regardless of the inclusion or omission of proteinase K in the comet assay. CONCLUSIONS: No DNA damage in brain cells was detected following exposure of rats to 2450 MHz microwaves pulsed-wave at a specific absorption rate of 1.2 W kg(-1) regardless of whether or not proteinase K was included in the assay. Thus, the results support the conclusion that low-level 2450 MHz pulsed-wave microwave exposures do not induce DNA damage detectable by the alkaline comet assay.

Lipid peroxidation as pathway of aluminium cytotoxicity in human skin fibroblast cultures: prevention by superoxide dismutase+catalase and vitamins E and C.

Lipid peroxidation is one of the main manifestations of oxidative damage and has been found to play an important role in the toxicity and carcinogenicity of many xenobiotics. In the present study, we investigated the possible induction of lipid peroxidation by aluminium in human foreskin fibroblast cultures by assaying the malondialdehyde (MDA) produced inside the cells. The MDA-thiobarbituric acid (TBA) adduct was assayed by HPLC using fluorometric quantification after extraction in n-butanol. Lactate dehydrogenase (LDH) release was used as a marker of aluminium toxicity. MDA production was significantly increased after 24 h incubation with aluminium and paralleled LDH release. Superoxide dismutase (SOD)+catalase and vitamins C and E added in the culture medium as oxygen radical and free radical scavengers were efficient in preventing MDA production by aluminium, indicating that oxidative processes are one of the main pathways whereby this metal induces cytotoxicity. The latter is also largely prevented, thus confirming the link between oxidative stress induced by aluminium and its cytotoxicity in human skin fibroblasts.

Transplacental passage of aluminum from pregnant mice to fetus organs after maternal transcutaneous exposure.

Aluminum is present in tap water, antiperspirants and cosmetics up to 20%. Teratogenicity of aluminium was clearly identified after per os or intravenous administration. Malformations and other alterations by aluminium intoxication were evaluated in fetus. In the present study, we investigated the possible transplacental passage of aluminium and its accumulation in the tissue after cutaneous uptake. Female Swiss mice received aluminium chloride by cutaneous way (0.4 micrograms/day) during 20 days of gestation. The samples were assayed for aluminium quantification by graphite furnace atomic absorption with Zeeman correction. This treatment led to an increase of aluminum in maternal and fetus samples (serum, amniotic fluid and organs) as compared to controls.

[Behçet disease in children. 3 Tunisian cases and review of the literature]. / La maladie de Behçet de l'enfant. A propos de 3 observations tunisiennes et revue de la littérature.

OBJECTIVE: To describe epidemiological, clinical and evolutive features of ophthalmological involvment of Behçet disease in children in tunisian patients. PATIENTS AND METHODS: In a retrospective study from 1990 to 1996, we collected three observations in children in 130 recorded cases of Behçet disease. Patients have been explored by a complete ophthalmologic staging and are treated and followed in our institution for theirs oculars problems. RESULTS: The three children, all males, aged from 12 to 13 years, represented 2.3% of all the Behçet disease diagnosed during the same period. Oral and/or genital aphtosis are present in all 3 cases and cutaneous or articular involvement is seen in 2 patients. Ocular Behçet disease involvement, bilateral in all the cases, is dominated by uveitis (posterior in 3 patients or anterior in 2) complicated by macular edema in 3 cases and cataract or pseudo-trou in 1 case. CONCLUSION: Behçet disease in children is characterized by the frequency of familial forms and articular involvement. The most characteristic ocular feature is represented by the posterior uveitis with a visual prognosis poor in short term. Specific criteria of Behçet disease is necessary for children for a early and best identification.

[Analysis of optic nerve head by confocal scanning laser ophthalmoscope in ocular hypertension]. / Analyse de la topographie de la tête du nerf optique par l'ophtalmoscope laser à balayage confocal dans les hypertonies oculaires.

PURPOSE: To analyze optic nerve head topography using confocal the scanning laser ophthalmoscope (CSLO) in ocular hypertension in comparison to normal eyes. PATIENTS AND METHODS: We examined 25 patients with ocular hypertension and 27 normal controls. All of them had a complete ophthalmic examination. Optic nerve head analysis was performed by using a CSLO-type Heidelberg retina tomograph (HRT). The following stereometric parameters were evaluated: disc area, area and volume of cup, cup/disc ratio, area and volume of neuroretinal rim, mean and maximal cup depth, cup shape measure, height variation contour, mean retinal nerve fiber layer thickness, and retinal nerve fiber layer (RNFL) cross-section area. RESULTS: In ocular hypertension eyes, rim volume, height variation contour and RNFL thickness showed a statistically significant reduction compared to normal eyes. CONCLUSION: HRT appears to be an important tool in detecting early damage of retinal nerve fiber layer in ocular hypertension.

[Tuberculosis in African children: epidemiologic, clinical and therapeutic aspects (corrected)]. / La tuberculose de l'enfant en Afrique: aspects épidémiologiques, cliniques et thérapeutiques.

In the last 10 years since world health assembly declared re-emergence of tuberculosis to be a worldwide emergency, most countries have initiated control strategies based on the recommendations of the World Health Organization. Implementation of national control programs has not only been encouraged but also become a necessity in the face of the constantly increasing number of cases and HIV epidemic. Diagnosis of tuberculosis in children is difficult and reliable estimation of prevalence is difficult. The purpose of this study was to analyze diagnostic criteria in 1128 children in Algiers, Algeria. Short-course chemotherapy was also evaluated. A prospective study in 733 children showed that 6-month regimes administered in the framework of a national program are effective and led to few complications. Short-course treatment also promotes better patient compliance. Consideration was also given to prophylactic treatment for contact children and adverse reactions to BCG.

Cytogenetic analysis of tannery workers in Morocco.

This study investigated the possible genetic effects in blood lymphocytes of tannery workers from Morocco being professionally exposed to multiple chemical agents. It was shown that the frequencies of cells with chromosome aberrations and micronuclei were significantly increased in the lymphocytes of the workers compared with the frequencies found in an unexposed control population.

[Ocular coloboma associated with cervico-oculo-acoustic syndrome]. / Colobome oculaire associé au syndrome cervico-oculo-acoustique.

INTRODUCTION: Cervico-oculo-acoustic syndrome is an uncommon syndrome consisting of Klippel Feil syndrome, deafness, and Duane syndrome. We relate a new case of cervico-oculo-acoustic syndrome. CASE REPORT: We report the case of 15-month-old girl referred for esotropia of the right eye. Ocular examination revealed type 1 Stilling Duane syndrome in the right eye, in which we also noted microcornea, iris coloboma, and papillary and inferior chorioretinal coloboma sparing the macular area. The left eye was normal. The physical examination revealed Klippel Feil syndrome characterized by an extremely short neck with limited movement, a low posterior head line and fusion of the cervical vertebrae on radiography. The association of hearing loss (due to agenesis of the external ear) with Klippel Feil syndrome and Stilling Duane syndrome confirmed the diagnosis of cervico-oculo-acoustic syndrome. CONCLUSION: This case is unique because of the association of cervico-oculo-acoustic syndrome with ocular coloboma of the right eye. This association has not been reported previously in the literature.

[Expression of intercellular adhesion molecule type 1 in the conjunctiva of diabetic patients: a preliminary study]. / Expression de la molécule d'adhésion intercellulaire de type 1 au niveau de la conjonctive des patients diabétiques: une étude préliminaire.

PURPOSE: Recent research has incriminated adhesion molecules in the pathogenesis of diabetic retinopathy. These molecules have been found to be expressed in many cells participating in inflammatory processes and neovascularization. The purpose of our investigation was to study the expression of intercellular adhesion molecule type 1 (ICAM-1) in the conjunctiva of diabetic patients without retinopathy in comparison with normal human conjunctiva. PATIENTS AND METHODS: Fifteen conjunctival biopsies were obtained from diabetic patients without retinopathy. The ocular fundus examination and retinal fluorescein angiography were normal. The normal human conjunctiva were taken from five patients undergoing senile cataract surgery. Immunohistochemical analysis consisted of indirect immunoperoxidase using the monoclonal antibody ICAM-1. RESULTS: The adhesion molecule ICAM-1 was immunolocalized in epithelial, vascular endothelial, and inflammatory cells. The expression of this molecule was different in diabetic patients for the same duration. In the normal human conjunctiva, the expression of ICAM-1 was very low. CONCLUSION: This preliminary study shows that ICAM-1 is present in the conjunctiva of diabetic patients without retinopathy and thus may add new insights into the pathogenesis of diabetic retinopathy.

Bioaccumulation of water soluble aluminium chloride in the hippocampus after transdermal uptake in mice.

Normally, only very small amounts of ingested aluminium are absorbed and accumulated. Despite the percutaneous absorption of many drugs and chemicals, the skin has not been considered as a possible site at which aluminium could enter the body. Application of low aqueous concentrations of aluminium chloride (A1C1(3), 6H20) (0.025-0.1 micrograms/cm2) to healthy shaved Swiss mouse skin for 130 days led to a significant increase in urine, serum and whole brain aluminium, especially in the hippocampus, compared to control animals. This percutaneous uptake and accumulation of aluminium in the brain was greater than that caused by dietary exposure to 2.3 micrograms per day in feed and water. In vitro studies demonstrated the passage of aluminium through viable mouse skin. This study shows for the first time that aluminium is absorbed through the skin of mice in vivo and this contributes to a greater body burden than does oral uptake.

Effects of GSM-900 microwaves on the experimental allergic encephalomyelitis (EAE) rat model of multiple sclerosis.

The effects of acute exposure to GSM-900 microwaves (900 MHz, 217 Hz pulse modulation) on the clinical parameters of the acute experimental allergic encephalomyelitis (EAE) model in rats were investigated in two independent experiments: rats were either habituated or nonhabituated to the exposure restrainers. EAE was induced with a mixture of myelin basic protein and Mycobacterium tuberculosis. Female Lewis rats were divided into cage control, sham exposed, and two groups exposed either at 1.5 or 6.0 W/kg local specific absorption rate (SAR averaged over the brain) using a loop antenna placed over their heads. There was no effect of a 21 day exposure (2 h/day) on the onset, duration, and termination of the EAE crisis.

Epigenetic properties of fumonisin B(1): cell cycle arrest and DNA base modification in C6 glioma cells.

Fumonisin B(1) produced by the fungus Fusarium moniliforme is a member of a new class of sphinganine analogue mycotoxins that occur widely in the food chain. Epidemiological studies associate FB(1) with human oesophageal cancer in China and South Africa. FB(1) also causes acute pulmonary edema in pigs and equine leucoencephalomalacia. This disease is thought to be a consequence of inhibition by FB(1) of cellular ceramide synthesis in cells. To investigate further on this pathogenesis, the effect of FB(1) was studied on cell viability (3 to 54 microM of FB(1)), protein (2.5 to 20 microM of FB(1)) and DNA syntheses (2.5 to 50 microM of FB(1)), and cellular cycle (3 to 18 microM of FB(1)) of rat C6 glioma cells after 24 h incubation. The results of the viability test show that FB(1) induces 10 +/- 2% and 47 +/- 4% cell death with, respectively, 3 and 54 microM, in C6 cells. This cytotoxicity induced by FB(1) was efficiently prevented when the cells were preincubated 24 h with vitamin E (25 microM). FB(1) displays epigenetic properties since it induced hypermethylation of the DNA (9-18 microM). Inhibition of protein synthesis was observed with FB(1) with an IC(50) of 6 microM showing that C6 glioma cells are very sensitive to FB(1); however, the synthesis of DNA was only slightly inhibited, up to 20 microM of FB1. The flow cytometry showed that the number of cells in phase S decreased significantly as compared to the control p = 0.01 from 18. 7 +/- 2.5% to 8.1 +/- 1.1% for 9 microM FB(1). The number of cells in phase G(2)/M increased significantly as compared to the control (p