study on the postnatal development and aging changes of the neurosecretory nuclei of the hypothalamus [supraoptic and paraventricular nuclei] in the albino rat

The hypothalamus is a distinct neurological entity concerned with a variety of regulatory processes. Recently, the prescence of variations in the level of neurosecretions wth the progress of age was reported. To study the changes in the structure of magnocellular neurons in the paraventricular and supraoptic nuclei during the period of postnatal development. Furthermore, to study the changes which occurred in the structure of these neurons in the old age had been studied. A total of 52 albino rats were used. The age groups of the animals include: one day, 10 days, 20 days, 2 months and 2 years old animals. Brains were processed to be studied with Einarson's gallocyanin-chrome alum stain, Golgi- Cox method and transmission electron microscope. In addition, the number of cells in the magnocellular part of the paraventricular and supraoptic nuclei were measured in all studied age groups and statistically analyzed. In the newly born rats, the paraventricular and supraoptic nuclei were composed of small rounded condensed cells. At the age of 10 days old rats, the paraventricular nucleus appeared to be well differentiated into ventromedial [parvocellular] and dorsolateral [magnocellular] parts. With the progress of age from 10 days up to the adult stage, the cells of the supraoptic nucleus and the magnocellular part of the paraventricular nucleus appeared to be densely stained which indicated increase in the Nissl granules. Ultrastructural study showed that the cells had abundant amount of free ribosomes, rough endoplasmic reticulum and mitochondria. The nucleus had fine dispersed chromatin. Golgi-Cox study showed marked increase in extension and branching of dendrites with the progress of age during the developmental period. Morphometric study showed significant increase in the number of cells from the new born up to the adult stage. In old aged rats, the cells of the paraventricular nucleus and the supraoptic nucleus appeared to be faintly stained. Some cells had vacuolated cytoplasm. Ultrastructural study showed marked decrease in the free ribosomes and the presence of many lipofuscin pigment in the cytoplasm of cells. The nucleus showed chromatin condensation and irregularity of the nuclear membrane. In addition, there was apparent decrease in the amount of the synaptic vesicles in the presynaptic terminals making contacts with the magnocellular neurons. Golgi-Cox study revealed marked decrease in the extension and branching of dentrites. Morphometric analysis showed significant decrease in the number of cells. This study demonstrated in the presence of structural changes in the magnocellular part of the paraventricular nucleus and supraoptic nucleus during the period of development. In old age, the presence of many degenerative changes was observed. This cytoarchitectonic analysis and morphological study could help in the explanation of the functional differences in the various ages

Formulation and evaluation of acyclovir microemulsions

Certain oils and surfactants were screened to select the most suitable ones for the preparation of microemulsions. Labrafil M 1944 CS, Labrafil M 2125 CS and Capryol 90 were selected as oils while Tween 80 was selected as a surfactant. Tween 80 was mixed with n-butanol [n-Bu] at different w/w ratios [K[m]] 1:2, 1:1, 2:1 and 3:1 as surfactant to cosurfactant [S/CoS] respectively. Pseudoternary phase diagrams were constructed using the selected oils [Labrafil M 1944 CS, Labrafil M 2125 CS and Capryol 90] with the different K[m] ratios. Microemulsion formulations were prepared using Labrafil M 1944 CS, Tween 80 and n-Bu with K[m] 2:1. The physicochemical characteristics involving viscosity, refractive index [RI], conductivity and pH were determined for these systems. In addition, the solubility of acyclovir in the prepared microemulsion systems [MEs] was measured. Acyclovir was incorporated to three MEs [ME[10], ME[50] and ME[80]] representing three different regions in the phase diagram; water in oil [w/o], bicontinuous [Bc] and oil in water [o/w] respectively. All of the prepared formulations were subjected to thermodynamic stability studies. The droplets size, polydispersity index [PDI] and zetapotential [ZP] of both before and after drug incorporation were determined. Acyclovir release from drug loaded MEs was determined and the kinetic of the release data was calculated. The conductivity and viscosity results proved the presence of three regions in the phase diagram [w/o, Bc and o/w]. The refractive index showed that the prepared MEs were transparent and isotropic. All the formulations were thermodynamically stable. The droplet size of drug loaded MEs was higher than that of corresponding unloaded ones but all have droplet size in nano range. PDI was found to be less than 0.5 and ZP in the range of-0.101 to 2.5 mV. Release of acyclovir from ME[80] [0.1, 1.99, 17.98 and 79.92 w/w for acyclovir, oil, S/CoS and water respectively] was the highest among the other ones, Model of non-Fickian "anomalous" transport release was the mechanism of drug release from the selected MEs. In conclusion, stable isotropic microemulsion systems using Labrafil M 1944 CS, Tween 80 and n-butanol as oil, surfactant and cosurfactant respectively with K[m] 2:1 could be formulated. The viscosity and electric conductivity results proved the presence of three areas; w/o, Bc and o/w in phase diagram. Acyclovir could be loaded into different microemulsion systems. The percent drug release increased by increasing the water content of microemulsion

Formulation and evaluation of metronidazole bioadhesive matrices for treatment of periodontitis

Metronidazole [Mz] [an anaerobic antibacterial agent] was incorporated into different bioadhesive matrices including gels and films using carbopol 934p [4%], chitosan [3%] and hydroxypropyl methyl cellulose [HPMC] [3%]. Penetration enhancers including menthol [1%] or oleic acid [OA] [5%, 10%] were incorporated in such formulations. The bioadhesive forces of the prepared matrices were determined and expressed as detachment stresses [Dyne/cm[2]]. Permeability of Mz across ear rabbit skin and enhancement ratios [ER] were studied. The effects of selected Mz formulations on the healing rate of experimentally induced periodontitis in guinea pigs were estimated and histologically compared between treated and control groups. The obtained results showed that the gel formulations containing carbopol 934p exhibited maximum bioadhesive force with detachment stress equals to 66.98x10[2] dyne/cm[2] followed by those containing chitosan [42.45x10[2] dyne/cm[2] and HPMC [26.41x10[2] dyne/cm[2]. There was a statistically significant difference [P<0.05] between the detachment stresses of gel formulations containing penetration enhancers and the corresponding ones without penetration enhancer. HPMC based films had bioadhesive force [19.33, 16 and 13.67x10[2] dyne/cm[2] higher than those based on chitosan [5.33 and 7.33x10[2] dyne/cm[2]. Also, it was noticed that the chitosan gel containing 1% menthol had the highest ER [5.13] among other gel formulations. On the other hand, chitosan based film containing 5% OA has the highest ER [1.73] among films. The effects of the selected formulations on the healing periodontal wound showed that bioadhesive chitosan gel containing menthol had accelerated the periodontal wound healing more than chitosan based film containing oleic acid

Aging changes of the olfactory bulb of albino rats

The olfactory bulb plays a central role in relaying olfactory information from the olfactory epithelium to the olfactory cortex. Olfactory loss is a common age-related complaint that may be caused by changes in the anatomy of the structures required which are required for olfaction [for example, change in the olfactory bulb]. The aim of the work is to study the structural changes which occur during aging in the olfactory bulb of albino rats. Twenty albino rats were used. The animals were subdivided into two age groups: adult and aged [24 months]. The animals were anaesthetized, perfused with appropriate fixative solution, then the animals were killed and brains were extracted and specimens of olfactory bulbs were dissected. For each group, some specimens were fixed in Bouin's fluid and after routine histological technique were embedded in paraffin. Other specimens were sectioned and stained with Einarson's Gallocyanine solution to study the cellular histology and morphology of the olfactory bulb. Other specimens were fixed in Golgi-Cox solution and embedded in cellodin and dendritic organization of the neurons of the olfactory bulb was examined. Also other specimens were fixed in 5% buffered glutaldehyde and electron microscopic technique was made, semi thin and ultra thin sections were obtained and examined to show the ultra structure of the neurons of olfactory bulb. The results revealed that aging induced reduction in the thickness of the layers of olfactory bulb, decreased neuronal density of the mitral cells with decreased dendritic arborization of the neurons. Also elecrtomicroscopic feature of the aged olfactory bulb revealed evidence of nuclear damage, perinuclear vacuolation, dilated Golgi and cisternia of rough endoplasmic reticulum with destructed mitochondria

study on postnatal development and ageing changes of red nucleus in the albino rat

The red nucleus is one of the most important structures in the midbrain tegmentum. It plays an important role in the control of motor activities. The aim of the present work is to demonstrate the structure of the red nucleus and the characteristics of its constituent neurons during the various stages of postnatal development, it also includes the study of the ageing effect on the features of its cells. In this work, a total number of 40 albino rats was used. The following postnatal age groups of animals were studied; newly born, seven days, fifteen days and three months old [adult rats] in addition to the aged group of animals [two years old rats]. Animals were sacrificed and the midbrain region was dissected. In each age group, three midbrain specimens were processed to be studied by Einarson's Gallocyanin stain and another three specimens were processed to be studied by Golgicox method. The ultrastructural study for the cells of the red nucleus was done by transmission electron microscope. By using Gallocyanin stain, the red nucleus appeared as a circumscribed mass of cells. The caudal magnocellular part was composed mainly of large neurons and few medium and small sized neurons. The rostral parvocellular part consisted mainly of medium and small sized neurons. The cellular content of Nissl granules increased gradually from the newly born age up to the adult stage. In the aged group of animals, the cells of the red nucleus appeared to be lightly stained as compared to the adult animals indicating loss of Nissl granules. Golgi stain revealed that the caudal magnocellular part of the red nucleus was formed of different types of cells [multipolar, pyramidal and fusiform cells]. Their nerve processes showed gradual increase in the length and branching with the progress of age up to the adult stage. In the aged group of animals, these neurons showed a decrease in the extension of the nerve processes as compared to the adult group. The ultrastructural study of the caudal magnocellular part of the red nucleus in the adult animals revealed that the large neurons were characterized by the presence of rounded nucleus while the medium sized neurons had an invaginated nucleus. The cytoplasm of these cells was rich with ribosomes, rough endoplasmic reticulum and mitochondria. Several types of axosomatic synaptic terminals appeared to be present. In the aged animals, the ultrastructural study of these cells showed marked decrease in the amount of ribosomes and rough endoplasmic reticulum as compared to the adult animals. There was also accumulation of lipofuscin granules in their cytoplasm. It was concluded from this study that during the development of the red nucleus, its constituent neurons showed a progressive increase in their content of Nissil granules from the newly born age up to the adult stage. Their nerve processes also showed increase in the extension and branching. The wide variety of synaptic terminals with rubral neurons indicated the presence of several sources involved in the integration of descending motor information. In the aged animals, the rubral neurons showed several degenerative changes that could lead to impairment of motor activities

Foot measurements and their relation to body weight and height for Assiuti children

In this study, foot length, foot width, stature and body weight of 3000 individuals [1500 males and 1500 females] aged 04-18 years old were taken from different schools of Assiut. Standard growth charts for foot length, foot width, stature and body weight were recorded. The results showed that foot length and foot width measurements of males were significantly higher than females. The growth spurts and the maturation of the foot length and the foot width of the females succeeded the males. A highly significant positive correlation between each of the stature and the body weight with each of the foot length and the foot width in both sexes was recorded. The correlation between the stature and the foot length was higher than that between the stature and foot width. Also, the correlation between the body weight and the foot width was better than that between the body weight and foot length. A highly significant positive correlation was found between foot length and the foot width in both sexes. Multiplication factors of the different studies variables were calculated for both sexes at different ages to estimate the stature and the body weight by multiplying the foot length or foot width by its suitable multiplication factor. Simple linear regression analysis was also done for all variables at all cases and four general regression formulae were introduced for estimation of stature and body weight of any individual from foot length and the foot width

Synthesis and reactions of some arylazo derivatives of B-diketones

Claisen condensation of both visnaginone methyl ether and Khellinone methyl benzoate lead to the formation of w-benzoatovisnaginone methyl ether and w-benzoate-Khellinone methyl ether. The B-diketones couple with aromatic diazonium compounds in the presence of sodium acetate to give the arylazo compounds. The arylazo compounds react with diazomethane, hydrazine hydrate, phenylhydrazine or hydroxylamine hydrochloride to form pyrazole or isoxazole derivatives