Ultrastructural developmental study of bronchial epithelium in one-humped camel

The putative respiratory epithelium lining of the bronchial tree of 20-60 mm crown-rump length [CRL] camel fetuses displayed the staggered nuclear organization characteristic of single cilium on their apical surfaces. The bronchial epithelium revealed a clear evidence of ciliogenesis, which occurred as early as 70 mm CRL, starting in the main bronchi and gradually proceeding distally, along the developing bronchial tree. The ciliogenic cells were gradually increased with gestational age. in fetuses of 70-370 mm CRL, the bronchial epithelium displayed a myriad of disintegrating sloughed apoptotic cells intermingled with ciliated and ciliogenic cells together with few non-ciliated microvillus types. Mitochondrial swelling, dilatation of the rough endoplasmic reticulum, vacuolation of the of the cytoplasm, distortion of the intercellular junctions, together with clumping of the nuclear chromatin were the early signs of cellular apoptosis. With time, the regressing apoptotic cells tended to detach themselves from their neighbors and underlying basement membrane moved upwards and sloughed into the airway lumen. These morphological alterations, concerning the disintegrating sloughed apoptotic cells, were first observed in the main bronchi and gradually proceeded by age towards the bronchiolar branches. In adult camels the bronchial epithelium was formed mainly of ciliated and non-ciliated microvillus cells; however, that at term of gestation was composed of ciliated cells, non-ciliated microvillus cells; however, that at term of gestation was composed of ciliated cells, non-ciliated microvillus types together with some cells possessing surface microplicae

Microscopical changes of the interstitial cells of the testis in adult albino rat after diazepam administration

The present work was carried out to study the effect of diazepam administration at different durations on the structure of the interstitial cells of the rat testis. A total number of thirty-two adult albino rats were used in this study. They were classified into three groups: a control group and two experimental ones. A control group [GI] comprised eight animals. The 1st experimental group [GII] comprised 16 animals and divided into two equal subgroups [GIIa and GIIb] received diazepam for 15 days [short duration] and for 45 days [long duration] respectively. The 2nd experimental group [withdrawal group] comprised eight animals and received the drug for 45 days and sacrificed two months after the last injection. The testes of all animals were prepared for microscopical examination. It has been found that diazepam causes proliferation and activation of the Leydig cells when administered for short periods. The cells showed large number of mitochondria and abundant smooth endoplasmic reticulum i.e active secretory cell. While, after long duration of diazepam administration, the Leydig cells showed degenerative changes in the form of small mitochondria with destructed crestae. The cells exhibited irregular cytoplasmnic vacuoles. The nuclei showed chromatolysis. Highly active macrophages were also seen. Two months after stoppage of the drug some of the affected Leydig cells were regenerated and showed structure similar to that of the control. The interpretations of different interactions of Leydig cells and macrophages were discussed