Histological study on the effect of gasoline on guinea pig epidermis: can flavonoid extract reverse this effect?

Car fuel, containing gasoline, is reported to have an irritative effect on mammalian skin. This study aimed to detect the cellular changes in the epidermis of male guinea pig back skin evoked by repeated exposure to gasoline and to evaluate the role of flavonoid extract in reversing these changes. Thirty-five guinea pigs, divided into a control [n=5] group I and an experimental [n=30] group II were used. The latter was divided into two subgroups; the guinea pigs in the first subgroup [group IIa] were painted with gasoline twice daily for 21 days and those in the second [group IIb] were treated with flavonoid extract after previous gasoline dermal application. Animal skin was dissected and processed for light and electron microscopic examination; further, statistical analysis was performed to compare the epidermal thickness in different groups. Naked eye examination of skin of guinea pigs in group IIa showed erythema and ulceration. In addition, a significant increase in epidermal thickness was observed by light microscopy. Ultrastructural changes include an ill-defined dermo-epidermal junction and basal layer cells showing an electron-dense cytoplasm, increased lysosomal dense bodies, and swollen mitochondria. Their nuclei showed an irregular nuclear envelope and peripheral chromatin condensation. The prickle layer cells showed dissolution of desmosomal junctions and cytoplasmic vacuolation. Granular cell layers showed a marked decrease in fibrillar contents and the horny layer showed separation of individual layers by flocculent-filled spaces. The flavonoid-treated group showed a significant decrease in epidermal thickness [compared with the gasoline-painted group] and most of the epidermal cells appeared normal with intact nuclei. Safety measures, as well as orientation programs, are recommended for car fuel-filling workers exposed to continuous contact with gasoline, to avoid its drastic effect on skin. Application of flavonoid orange extracts is recommended as they ameliorate this effect

Endoscopic saphenous vein harvesting [ESVH] versus open saphenous vein harvesting [OSVH]: a light and electron microscopic study

Following the introduction of aorto-coronary bypass grafting in 1968, the use of saphenous veins as conduits for revascularization has become an established method treatment for symptomatic coronary artery disease. The role of damaged endothelium in early graft occlusion has been extensively demonstrated. Seventy percent of early graft occlusions in coronary artery bypasses were caused by thrombi overlying areas of endothelial loss. Was to assess by morphological and histological examination the degree of vascular trauma of saphenous vein conduits harvested by an endoscopic technique compared with those harvested by conventional open methods, in order to evaluate the safety of both techniques. Saphenous vein specimens were collected from 120 patients undergoing elective Coronary artery bypass grafting [CABG] surgery and randomized into two groups: Endoscopic Saphenous Vein Harvesting [ESVH] group A and Open Saphenous Vein Harvesting [OSVH] group B. Small parts of the vein were processed for routine light and scanning electron microscopy assessment. Most of the examined sections of the saphenous vein showed mild to moderate histological disruption in the form of intimal endothelial loss and medial tears. Scanning electron microscopy showed some endothelial separation, basement membrane exposure and adherent blood cells and fibrin. These findings were more evident in group A than in group B, but the statistical analysis of the quantitative data showed that this difference was of no significant value. This study proved that ESVH adversely affects the histological structure of the vein more than OSVH, but the difference between both techniques remains statistically insignificant. This means that the OSVH still has the upper hand in preservation of vein integrity compared to ESVH and more skilful training of the surgeons to safely harvest the veins endoscopically is strongly needed