Histological study of the effect of bone marrow-derived mesenchymal stem cells on healing of skin defect in adult male albino rats

Despite advances in wound care, skin loss results in significant morbidity and mortality. There is increasing evidence that bone marrow-derived mesenchymal stem cells [BM-MSCs] are useful for tissue regeneration because of their multipotency and easy isolation and culture. The objective of this study was to evaluate the efficacy of local administration of in-vitro-expanded BM-MSCs in the healing of experimentally induced full-thickness excisional wounds in adult male albino rats. Thirty-five adult male albino rats were used. They were divided into three groups. In group I rats, BM was isolated and cultured and skin specimens were obtained as a control. In group II rats, a full-thickness circular skin wound of 5mm in diameter was inflicted on the mid back of each rat and was examined on days 3, 7, and 14. In group III rats, the wound was inflicted as in group II, which was then treated with BM-MSCs and examined as in group II. The wound areas were excised and used for histological and immunohistochemical studies for CD105. Morphometric analysis was performed for assessment of epidermal thickness, area percentage of collagen and elastic fibers, and number of CD105-positive cells. Wounds treated with BM-MSCs [group III] showed evidence of re-epithelialization, increased epidermal thickness, hair follicle formation, collagen, and elastic fibers compared with wounds in group II. Similarly, the number of CD105-positive cells was prominently increased in the skin of the same group. Local administration of in-vitro-expanded BM-MSCs accelerates and promotes healing in full-thickness excisional wounds

Histological study on the possible protective action of ginseng on the injurious effect induced by acrylamide on the midbrain in adult male albino rat

Acrylamide is a synthetic chemical compound commonly used in many branches of industry. Researchers have found acrylamide in certain foods that were heated to a temperature above 120[degree]C. Ginseng is a widely used herbal medicine with numerous beneficial effects. Ginseng is suggested to contribute to a protective effect in neurodegenerative disorders. The aim of the present study was to evaluate the possible protective effect of ginseng against the midbrain injury induced by acrylamide in adult male albino rats. A total of 35 adult male albino rats were used. They were divided into three groups. Group I [15 animals] was allowed water ad libitum and fed a standard diet [control]. Group II [10 animals] was given acrylamide orally by means of a gastric tube daily at a dose of 30 mg/kg for 4 weeks. Group III [10 animals] was given acrylamide daily at the same dissolution, dose, route and duration as group II concomitantly with ginseng solution through a gastric tube at a dose of 20 mg/kg. Samples from the brainstem were taken and processed for light and electron microscopic investigation. Light microscopic examination of the midbrain of the acrylamide-treated animals showed signs of injury. Glial fibrillary acidic protein-positive cells were more abundant in the midbrain of treated animals compared with control animals. Ultrastructural study of the midbrain of the acrylamide-treated group showed dilated RER in association with mitochondria with destroyed cristae. Many myelinated nerve fibers showed degenerative changes. These structural changes were much less pronounced in animals concomitantly treated with acrylamide and ginseng. Ginseng can reduce the severity of the injurious effects induced by acrylamide

Effect of aflatoxin-B1 on rat cerebellar cortex: light and electron microscopic study

Introduction: Aflatoxin contamination of foods is a worldwide problem, especially in developing countries. The effects of aflatoxins on the cerebellum are not well studied

Aim of the study: The aim of the present study was to evaluate the possible neurotoxic effects of aflatoxin B1 on the cerebellar cortex of adult male albino rats

Materials and methods: A total of 30 adult female albino rats were used. They were divided into two groups. Group I [10 animals] was allowed water ad libitum and fed a standard diet [negative control]. Group II [20 animals] was administered 5 ml aflatoxin B1 orally by a gastric tube every week for 8 consecutive weeks. Samples from the cerebella were taken and processed for light and electron microscopic investigation

Results: Light microscopic examination of the cerebellar cortex of aflatoxin-treated animals showed its prominent neurotoxic effect on the Purkinje cell layer, with less effect on the granular and molecular layers. Glial fibrillary acidic protein-positive cells were more abundant in the three cortical layers of treated animals compared with the control animals. Ultrastructural study of the cerebellum of the aflatoxin-treated group showed dilated Golgi complex and accumulation of secondary lysosomes in association with nuclear shrinkage and irregularity within Purkinje cells. Many myelinated nerve fibers and nerve cell processes in the molecular and granular layer belonging to the affected nerve cells showed degenerative changes

Conclusion: It could be concluded according to this study that aflatoxin B1 has a neurotoxic effect on the cerebellar cortex of adult female albino rats

histological study of the effects of SMO gene activation in mouse skin

Activating mutations in the SMO [smoothened] gene have been isolated from human basal cell carcinoma. Basal cell carcinoma [BCC] is the most common human malignancy worldwide. Modeling this type of malignancy in animals would help in studying this disease in depth. This study was carried out to characterize a mouse model having SMO gene activated in its skin to see whether it will develop BCC and serves as a model for this disease. In this study, a transgenic mouse model was characterized in which SMO gene was only activated in its skin. The specimens were processed for paraffin sections. They were used for haematoxylin and eosin staining, immunostochemical staining by keratin 10, BrdU staining and in situ hybridization to detect Gli1 mRNA. In this model, epidermis is thickened with areas of epidermal down growths invading the underlying dermis, one of the protein markers of BCC[K 10] is expressed, one of the signs of epidermal cell proliferation [increased BrdU incorporation] is displayed and one of the hedgehog signaling pathway-a pathway involved in human basal cell carcinoma-target genes [Gli1] is upregulated. These changes are similar to the changes reported in human basaloid follicular hamartoma, but BCC does not develop even in elderly mice. The results of this study indicate that activation of SMO gene in mouse skin appears to be insufficient for the development of BCC