Preparation of an acellular dermal matrix using the freeze-thawing technique with and without gamma irradiation

An acellular dermal matrix [ADM] is a dermal substitute in which the skin is treated to remove epithelial and dermal cellular components. To compare the histological and immunohistochemical structures of ADMs prepared using the freeze-thawing technique with or without gamma irradiation. Twenty-one human skin specimens were used and divided into three equal groups: group I [control group], group II, in which skin specimens were subjected to three repeated freeze-thawing cycles, and group III, in which skin specimens were subjected to three repeated freeze-thawing cycles and subsequent exposure to 5000 rad gamma irradiation. Skin specimens from the previous groups were examined histologically and immunohistochemically for laminin. A morphometric study was carried out for the determination of the number of cells per high-power field [hpf] in both the papillary and the reticular dermis. Both methods of ADM preparation resulted in extensive extraction of cellular components with preservation of the basic dermal architecture as there was a highly significant decrease in the number of cells/hpf in both layers of the dermis in groups II and III as compared with the control group [P<0.001]. However, there was further decellularization in group III as there was a highly significant decrease in the number of cells/ hpf in both the papillary and the reticular dermis in group III as compared with group II [P<0.001]. Immunohistochemical stain of laminin revealed preservation of the epidermal basement membrane in groups II and III. A combination of irradiation and a freeze-thawing technique is recommended in the preparation of ADM for efficient decellularization

Histological study on the effect of garlic extract on the coronary arteries in male albino rat following high cholesterol diet

Twenty five male albino rats were used in the current study to evaluate the role of garlic extract in management of coronary artery changes that result on top of intake of high cholesterol diet. The animals were divided into 5 equal groups. Group I was a control group. Group II was given garlic extract orally. Group III allowed high cholesterol diet in the form of egg yolk. Group IV received garlic extract concomitantly with the high cholesterol diet [HCD]. Group V was given high cholesterol diet, then the diet was stopped and garlic extract was allowed for 2 weeks. After the end of the experiment the left side of the heart was dissected out. The specimens were possessed sections were cut and stained by H and E, aldehyde fuchsin and oil red-O stain. Blood samples were collected for measuring of blood cholesterol level. Following intake of high cholesterol diet accumulation of fat was observed in the intima and media. There was highly significant increase in the intimal and medial thickness. The internal elastic lamina was seen to be disorganized and discontinous in some areas. The endothelium of the intima showed localized areas of hyperplasia and there was adherence of blood elements to it. Giving garlic extract concomitantly with high cholesterol diet resulted in a histological picture of the coronary arteries more or less similar to that of the control group. When garlic was given after stopping of the high cholesterol diet, the histological picture of the coronary arteries did not show a significant improvement. In view of the previous results it could be concluded that garlic could be used as a protective agent against the changes produced by high cholesterol diet on the coronary arteries. It's role in treatment was not as that when used as a prophylactic measure