Aaijaz Ahmed Khan

The Effects of Progesterone on Hypoxic Ischemic Injuries in the Cornu Ammonis (CA) Region of the Hippocampus of Neonatal Rats

Hypoxia-ischemia (HI) is a major cause of brain damage in the newborn. Several studies elicited the neuroprotective effects of progesterone in adult rats but there is very little literature available on neonatal rats. Therefore the present study is undertaken to see the effect of progesterone in hypoxic ischemic brain injury in neonatal rats, using an established neonatal HI rat pup model. Sevenday- old rat pups were subjected to right common carotid artery ligation and then 60 minutes hypoxia. The first dose of progesterone to treatment group was administered by peritoneal injection (4 mg/kg), after 10 minutes of exposure and subsequent doses were given by subcutaneous injection at 6 h, 24 h and 48 h intervals. Control group was also exposed to HI and was given only the vehicle (peanut oil) through the same route and intervals as that of treatment group. After 96 h, the pups were perfused with 10% formalin and brains were sampled and stained with toluidine blue. Cells density and number of pyramidal cells of the hippocampal Cornu Ammonis (CA) regions were examined by stereological methods. The histomorphometric assessment of the effects of progesterone showed minimal but no significant protective value in the volume, cells density and total number of pyramidal cells of hippocampal CA region of the treatment and control groups (p>0.05) after HI. Our results concluded that 4 mg/kg of PROG had no significant neuroprotective effect in HI model of the neonatal rat’s hippocampus.

Interparietal Bone Variations in Accordance with their Ossification Centres in Human Skulls

El segmento interparietal superior de la porcion escamosa del hueso occipital es de origen membranoso y la parte inferior supraoccipital se desarrolla en el cartilago. De acuerdo con la literatura disponible, el segmento interparietal se osifica a partir de 2 a3 pares de centros y cada uno de estos centros cuenta con 2 nucleos. El hueso interparietal se forma debido a la falta de fusion de estos centros y / o sus nucleos. Muchas variaciones de hueso interparietal han sido reportados por investigadores. En el presente estudio, de 25 craneos humanos estudiados, seis craneos presentaban algunas variaciones interesantes de huesos interparietales. Cuatro huesos interparietales fueron encontrados en un craneo, dos huesos interparietales en un craneo y cuatro craneos presentaban un solo hueso interparietal (Os inca) en el lambda. Ademas, de los huesos interparietales, en tres craneos se observaron huesos suturales. Estas variaciones estaban en relacion con los centros de osificacion de la parte membranosa del hueso occipital. Por su ubicacion y forma, se concluyo que los huesos se formaron debido a la falta de fusion entre si de los nucleos de los centros del tercer par de osificacion, con otros opuestos y con los centros del segundo par. Se concluye, ademas, que estos casos de huesos interparietales eran diferentes de lo que se habia informado anteriormente por otros investigadores y esto nos impulso al estudio, el cual puede ser util para anatomistas, antropologos, radiologos y neurocirujanos.

Evaluation of the protective effects of tocotrienol-rich fraction from palm oil on the dentate gyrus following chronic restraint stress in rats

Exposure to chronic restraint stress has been shown to cause a number of morphological changes in the hippocampal formation of rats. Tocotrienol, an isoform of vitamin E, exhibits numerous health benefits, different from those of tocopherol. Recent studies have demonstrated that tocotrienol prevents stress-induced changes in the gastric mucosa, thus indicating that it may also protect other organs such as the brain from the damaging effects of stress. Therefore, the aim of the present study was to investigate the protective effect of tocotrienol-rich fraction (TRF) extracted from palm oil on the dentate gyrus of rats following exposure to chronic restraint stress. Thirty-six male Sprague Dawley rats were divided into four groups: control, stress, tocotrienol and combination of stress and tocotrienol. Animals were stressed by restraining them for 5 hours every day for 21 consecutive days. TRF was administered via oral gavage at a dose of 200 mg/kg body weight. Our results showed that the plasma corticosterone level was significantly increased in response to stress, compared to the control. The results confirmed previous findings that chronic restraint stress suppresses cellular proliferation and reduces granule cell number in the dentate gyrus. However, TRF supplementation failed to prevent or minimize these stress-induced changes. Therefore, we conclude that TRF at the current dosage is not effective in preventing the morphological changes in the dentate gyrus induced by chronic restraint stress.

Normal values of foot arch parameters in adult Hausa population of Nigeria

Background: Deformities of foot arches have been implicated in various lower extremity injuries. Normal values of foot arch parameters have been studied in various populations. However, studies in Nigerian population are very limited and therefore require attention. Objective: The objectives of this study were to establish the normal values of foot arch parameters in adult Hausa population of Nigeria, to find the effect of gender on these parameters and to make comparison with previous studies in other populations. Materials and Methods: A total of 59 consented subjects (44 males, 15 females) that have no history of lower extremity deformity were recruited. Lateral radiograph of the right foot of each participant was taken in a bilateral standing position. For the medial longitudinal arch, navicular height (NH), first cuneiform height (FCH), calcaneal inclination angle (CIA), and calcaneal- first metatarsal angle (C1MA) were measured. Cuboid height (CH) and calcaneal-fifth metatarsal angle (C5MA) were measured for the lateral longitudinal arch. Measurements for angles and heights were performed using a universal plastic goniometer and a plastic ruler, respectively. Results: The mean (standard deviation [SD]) value of the NH was found to be 2.89 (0.54) cm, FCH 2.08 (0.44) cm, CIA 16.57° (3.30°), and C1MA 140.05° (5.63°). The mean (SD) of CH and C5MA was found to be 1.19 (0.31) cm and 160.96° (4.69°), respectively. There was no significant mean difference in those parameters between males and females. Conclusion: The mean values of foot arch parameters in adult Hausa population of Nigeria is comparable to previous studies on other populations, but generally lower than those of Caucasians. Similarly, our findings showed that gender has no significant effect on foot arch parameters.

The sciatic nerve in human cadavers — high division or low formation?

Variations of the sciatic nerve have been extensively studied in the past including its relationship with the piriformis muscle and associated clinical conditions like piriformis syndrome and sciatica. In the present study we noticed some interesting variations of the sciatic nerve, which were slightly different from the cases described earlier. In the previous studies most of the authors described the higher division of sciatic nerve and none of them discussed its formation. In this study we tried to look its formation from the sacral plexus and its divisions in the thigh. We noticed that in one cadaver the two components of the sciatic nerve originated directly from the sacral plexus and coursed down without merging in the thigh. Should this be called a higher division or non formation of the sciatic nerve? On the other hand in two other cadavers, the two divisions after emerging separately from the sacral plexus, united in the gluteal region and in the thigh respectively. Should we call this as higher division or low formation of the sciatic nerve? In two other cadavers the sciatic nerve emerged from the greater sciatic foramen below the piriformis and divided in the gluteal region itself. Ideally this should be called as higher division of sciatic nerve.