Background: Diabetes mellitus, a chronic disease with increasing prevalence worldwide, is known to be associated with thyroid disorders. Retinoic acid, a metabolite of vitamin A, is currently used for the treatment of diabetes and obesity. Aim of the work: The present study aimed to evaluate the possibility of using all-trans-retinoic acid (atRA) in reducing the structural changes of the thyroid gland and pituitary thyrotrophs in streptozotocin-induced diabetic rats. Materials and methods: Thirty adult male albino rats were divided into three equal groups: group I, control; group II, which included rats in which diabetes was induced by a single intraperitoneal injection of streptozotocin (100 mg/kg); and group III, which included rats in which diabetes was induced as in group II, followed by an intraperitoneal injection of atRA (2.5 mg/kg/day) from the third day. After 4 weeks, thyroid and pituitary specimens were processed for light and electron microscopic study. Results: Most thyroid follicles of diabetic rats were distended with colloid and lined with flattened thyrocytes with hyperchromatic nuclei and vacuolated cytoplasm that contained dilated rough endoplasmic reticulum, few colloid droplets, and few lysosomes. Some exfoliated cells were observed in the lumen. C cells had rarefied cytoplasm containing a few secretory granules. The number of mast cells showed a nonsignificant change. Thyrotrophs showed dilated rough endoplasmic reticulum, destroyed mitochondria, and decreased secretory granules. The atRA-treated diabetic group showed almost the same structural alterations in the thyroid gland, with even more changes in thyrotrophs. Conclusion: Despite its current use as a novel therapy for diabetes, atRA exerted no ameliorating effect on diabetes-induced histological changes in the thyroid gland and, moreover, exacerbated the changes of pituitary thyrotrophs.

Background: Aluminum chloride (AlCl3) is an environmental xenobiotic that induces free radical-mediated cytotoxic and reproductive toxicity. Nigella sativa oil (NSO) is an antioxidative agent reported to be important for detoxification. Aim: This study aimed to investigate the possible role of NSO in ameliorating the toxic effect of AlCl3 on the histological structure of the testis in male rats. Materials and methods: This study was carried out on 40 adult male rats, divided into four equal groups: group I, which served as the control group; group II (the AlCl3-exposed group), which received AlCl3 daily at a dose of 320 mg/kg/l in drinking water through a gastric tube for 1.5 months; group III (the AlCl3+NSO-treated group), which received NSO at a dose of 1 ml/kg orally concomitantly with AlCl3 for 1.5 months; group IV (the withdrawal group), which received only AlCl3 at the same dose for 1.5 months, after which the animals were left untreated for another 1.5 months. The animals of each group were processed for light and transmission electron microscopic study. Morphometric and statistical analyses were conducted. Results: Compared with the control group, administration of AlCl3 revealed significant changes in the seminiferous tubules, which appeared shrunken with disorganized germinal epithelium. Cellular vacuolations as well as sloughed spermatogenic cells into the lumen were observed. The interstitium was widened with interstitial hyperplasia. Ultrastructural examination of the AlCl3-exposed group revealed cells with dense cytoplasm and heterochromatic nuclei. Late differentiating spermatids showed deformed heads with widening of the subacrosomal space and redundant acrosome. Concomitant administration of NSO with AlCl3 showed amelioration of most of the histological changes in the AlCl3-intoxicated group. The withdrawal group showed persistence of many structural changes noticed in the AlCl3-intoxicated group with a significant difference compared with the AlCl3+NSO-treated group. Conclusion: NSO played a protective role against AlCl3-induced testicular damage.

Background: Aluminum chloride (AlCl3) is an environmental xenobiotic that induces free radical-mediated cytotoxic and reproductive toxicity. Nigella sativa oil (NSO) is an antioxidative agent reported to be important for detoxification. Aim: This study aimed to investigate the possible role of NSO in ameliorating the toxic effect of AlCl3 on the histological structure of the testis in male rats. Materials and methods: This study was carried out on 40 adult male rats, divided into four equal groups: group I, which served as the control group; group II (the AlCl3-exposed group), which received AlCl3 daily at a dose of 320 mg/kg/l in drinking water through a gastric tube for 1.5 months; group III (the AlCl3+NSO-treated group), which received NSO at a dose of 1 ml/kg orally concomitantly with AlCl3 for 1.5 months; group IV (the withdrawal group), which received only AlCl3 at the same dose for 1.5 months, after which the animals were left untreated for another 1.5 months. The animals of each group were processed for light and transmission electron microscopic study. Morphometric and statistical analyses were conducted. Results: Compared with the control group, administration of AlCl3 revealed significant changes in the seminiferous tubules, which appeared shrunken with disorganized germinal epithelium. Cellular vacuolations as well as sloughed spermatogenic cells into the lumen were observed. The interstitium was widened with interstitial hyperplasia. Ultrastructural examination of the AlCl3-exposed group revealed cells with dense cytoplasm and heterochromatic nuclei. Late differentiating spermatids showed deformed heads with widening of the subacrosomal space and redundant acrosome. Concomitant administration of NSO with AlCl3 showed amelioration of most of the histological changes in the AlCl3-intoxicated group. The withdrawal group showed persistence of many structural changes noticed in the AlCl3-intoxicated group with a significant difference compared with the AlCl3+NSO-treated group. Conclusion: NSO played a protective role against AlCl3-induced testicular damage.

Smoking has been positively associated with hearing loss in human. However, its effect on the cochlea has not been previously evaluated. Aim of work is to investigate the effect of nicotine, which is the primary pharmacological component of tobacco, on the structure of the cochlea of adult male guinea pigs. Fifteen male guinea pigs were classified into two groups: group I (control) and group II (nicotine treated group). Group II was further subdivided into two subgroups; IIA and IIB according to the dose of nicotine (3 mg/kg and 6 mg/kg, respectively). The cochlea was harvested and processed for light microscopy, transmission electron microscopy and scanning electron microscopy. Nicotine administration induced damage of outer hair cells which were distorted in shape with vacuolated cytoplasm and heterochromatic nuclei. Topography revealed damage of the stereocilia which included disorganization, bent and limp or complete loss and expansion of the surrounding supporting cells. These changes were more pronounced in the basal turn of the cochlea and mainly involved the outer hair cells. High dose induced more damage and resulted in protrusion of the apical poles of hair cells (blebing), particularly the outer two rows. Nicotine is proved to be harmful to the cells of the cochlea, particularly the outer hair cells of the basal turn. High doses induce blebing of hair cells.

Most of acetabular fractures especially those involving weight bearing dome must be anatomically reduced. Principles of management of any articular fractures of long bones apply to fractures of acetabulum. These principles include achievement of anatomical reduction of the joint surface, rigid stable fixation which can allow early active motion and preservation of soft tissue. Due to complications of extensive surgical exposures of reduction and fixation of acetabular fractures, minimal invasive techniques of reduction and stabilization of acetabular fractures has been evoluted. The concept of minimal invasive surgery still depends on achieving anatomical reduction and stable internal fixation but with the least soft tissue dissection. The minimal invasive fixation is achieved by using percutaneous periacetabular screws after fracture reduction either by closed means or by limited open reduction through mini-windows