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

Reproductive impairment of tilapia zillii [Gerv.] living in different basins of lake Mariut, Alexandria

This study aimed at inspecting pollution impact on the reproduction process of Tilapia zillii [Gerv.] living in three main basins of Lake Mariut. Our results revealed that there were two main seasons detected for males and females during a whole year of investigation, namely, non-spawning and spawning seasons. In males, though the two seasons started and ended simultaneously, gonadosomatic index values of males living in the relatively clean area were significantly higher than those of the other two polluted areas. However, no structural alterations could be detected in sections of male gonads from the three basins. All stages of maturation were represented in all gonad sections. In females, gonadosomatic index values of fish living in the relatively clean basin were significantly higher than those of fish living in the other two polluted areas. Females living in the relatively clean area attained two prominent peaks during the spawning season compared to one peak for the other two polluted areas. Spawning season for one of the two polluted areas was one month shorter than the reference area. Historically, belated and deformed maturation stages as well as ruptured and empty follicles were observed in female gonad sections from the two polluted areas

DNA analysis and tumor markers [CA 15-3 and CEA] in breast cancer

In this study, 40 females with infiltrating breast carcinoma and 10 females with healthy breast [as a control] were examined. Serum samples and fresh tumor breast tissue were collected from each case for tumor markers detection and flow cytometric [FCM] study, respectively. The results revealed a significant difference between all the most studied well known prognostic parameters [node negative/positive, diploid/aneuploid and low/high S-phase fraction [SPF]], except for the patients stage and ratio of events. CA 15-3 and CEA showed a highly significant difference between all the six parameters with a higher difference between control and patient groups. No single prognostic variable [DNA index [DNA-I] and ploidy, SPF, node status, tumor size, CA 15-3 and CEA] was correlated with all other variables in all subgroups and, so every one of them may add a prognostic value, specially if combined together [e.g. ploidy and SPF]. Interestingly, patients with grade II tumors [of favorable prognosis] had among them aneuploid tumors with bad prognosis, while those with grade III tumors [of bad prognosis] had diploid tumors with a good prognosis. In addition, among the three multiploidy cases [of worst prognosis there was a node negative case [of best prognosis]. Hence, ploidy estimation is important and useful in patient classification and treatment

Comparasion of three normovolaemic haemodilutions on pulmonary gas exchange and tissue oxygenation in cardiac surgery with extracorporeal circulation

Cardiopulmonaary bypass [CPB] with haemodilution is currently used as a common adjunctive measure in cardiac surgery. However, there is still much controversies as regards the effect of haemodilution on pulmonary gas exchange and tissue oxygenation after cardiac surgery with extracorporeal circulation. We have studied 60 adult patients, ASA II and III who were undergoing elective coronary artery bypass graft operation with CPB. Patients were allocated info three groups according to their final haematocrit after the end of extracorporeal circulation; group [I] haematocrit above 30%, group [2] haematocrit from 25%-30%, and group [3] with haematocrit between 21%-25%. Our study showed a significant impairment of pulmonary gas exchange after cardiopulmonary bypass as shown immediately after the end of bypass and continued all over the study period as shown by a decrease in the arterial oxygen partial pressure [PaO2] and arterial alveolar oxygen tension PaO2 /PAO2 and an increase in alveol-arterial oxygen tension gradient P [A-a] O2 and pulmonary shunt Qs /Qt. while no significant effect of the different haematocrit values was noted on the pulmonary gas exhange, in addition the tissue oxygenation parameters showed a stability in the oxygen consumption VO2 in spite of a marked decrease in the oxygen delivery DO2 this may be achieved through an increase in both oxygen extraction O2EX% and cardiac index CI

Thallium-201 scintigraphy in evaluation of breast masses

The purpose of the present study was to evaluate thallium-201 as a tumor seeking agent in patients with breast cancer. Forty-five female patients [20-67 years of age] with breast complaints were included in this study. After clinical examination, mammography and thallium-201 scintigraphy were performed and all cases were inspected pathologically to confirm the findings of both techniques. The results revealed that thallium-201 scintigraphy can reliably detect primary tumors of the breast with a high degree of sensitivity in group A which included 35 patients with no prior history of breast cancer. As 21 patients were found to have malignant breast lesions pathologically, the scintigraphic technique revealed only two false-negative cases out of them [sensitivity 90.4%, specificity 85.7% and accuracy 94.3%]

Portal tract changes nearby malignancy

More than 22% of undirected percutaneous liver needle biopsies that are performed in search of metastatic neoplasms yield false negative specimens. Failure of sampling is also, met with directed needle biopsy. However, histologic changes are often observed in the liver adjacent to space occupying lesions due to focal obstructor of bile and blood flow. These alterations were defined in 20 liver specimens, with metastatic and primary malignant neoplasms, and revealed a characteristic histologic triad consisting of proliferated and abnormal bile ductules, polymorphonuclear leucocytes in edematous portal tracts, and focal sinusoidal dilatation. The changes had been compared with histologic changes associated with major biliary obstruction with a significant frequency of variable [P <0.05]. Therefore, the observation of the histologic triad described here should lead to a continued search for space occupying tumor in the liver

Histopathological and electron microscopic studies of the kidney in experimentally infected mice with schistosoma mansoni

Fifty albino mice were individually infected with Schistosoma mansoni by paddling technique. Kidney biopsies were taken at the 12th week post-infection for histopathological examination both by the light microscope [LM] and electron microscope [EM]. The histopathologic and electron microscopic changes encountered were mainly mesangioproliferative glomerulonephritis [60 and mesangiocapillary glomerulonephritis [40% of infected mice]

Ultrastructural changes in hepatocytes after repeated ketamine anesthesia to albino rats

This work was designed to study the effect of repeated ketamine anaesthesia on the fine structures of hepatocytes in albino rats. Fifty adult albino rats of both sexes were the subject of this study. The body weight of these rats ranged from 250 - 350 g. All animals were healthy and in normal condition. These rats were divided into two equal groups [A and B]. Group A rats [treated group] were given 5 mg/kg ketamine Hcl intraperitoneally every 3 days for 5 times. Group B rats were treated as group A except that they were given a comparable amount of saline [diluent of ketamine] and served as control group. Two days after the last injection all rats were sacrificed by cervical dislocation. And laparotomy was done and small pieces of their livers were taken and prepared for electron microscopic examination. Electron microscopy of the liver specimens of treated group [group A] revealed some pathological changes in the fine structures of the hepatocytes. These pathological changes were, relative increase in the nuclear euchromatin [dispersed or active chromatin], increased number and size of mitochondria some of them showed demolished ridges, degenerative changes and opaque matrices, decreased number of rough endoplasmic reticulum and some of them were fragmented, increased number of smooth endoplasmic reticulum, Golgi apparatus, ribosomes and lysosomes. Also glycogen content was decreased while lipid droplets, pseudoinclusion bodies and electron dense bodies were increased in number. In conclusion, repeated ketamine anaesthesia in albino rats is toxic to the hepatic cell organelles

Aberrant hymenolepis nana in experimental infection

Experimental infection of normal healthy albino mice with 20000 H. nana eggs/mouse resulted in the production of a highly significant number of cyticercoids [P < 0.001] and strobilate forms [P < 0.001] with a prolongation of the time-course of infection. Severe mucosal lesions involving the whole small intestine were noticed. Extraintestinal larval forms were detected in the liver and lungs with the formation of multiple focal granulomatous reactions and evident tissue destruction. However, degeneration of disseminated larvae and regression in the size of such granulomas were obtained by time. The significance of these findings was discussed

Clinicopathological and Immunohistochemical findings in lymphocytic auto immune thyroiditis

Eighteen patients suffering from suspicious firm thyroid swelling, associated with pressure manifestations, were operated upon by subtotal or total thyroidectomy; 20 cases out of 80 showed lymphocytic infiltration, these cases were sub-classified according to the degree of lymphocytic and plasma cell infiltrate into 5 groups: Group I and II [focal lymphocytic thyroiditis], 8 cases, Group III and IV [Hashimoto's thyroiditis], 7 cases and Group V [Atrophic lymphocytic thyroiditis] 5 cases. These cases studied immunohisto chemically by using peroxidase anti peroxidase technique to find out a correlation between them. Between these three immunohistologically separable groups, there were many cases with features of all, considering the occurrence of such intermediate forms and some immunohistological similarities between them, and the positivity of thyroglobulin associated with thyroid, it is likely that these lesions are of different activities of the same immunological process starting by focal lymphocytic thyroiditis where as Hashimoto's thyroiditis lie in between

Influence of thermal stress on certain metabolic activities in aspergillus fumigatus

A thermotolerant fungus, Aspergillus fumigatus synthesized higher quantities of carbohydrates, lipids and proteins when cultivated at 45C than at 30C. Several amino acids were detected in the amino acids pool of the fungus, cultivated at 45C but not at 30C; lysine, ethyl- asparagine, methylcysteine methyl-glutamic acid and alpha amino adipic acid. While gamma-amino isobutyric acid and hydroxy norvaline were detected only at 30C. Several protein bands were detected in fungal extract grown at 45C while less were detected in fungal extract grown at 35 and 30C. Exogenous supplementation with various amino acids showed an increase in the fungal thermophily

Influence of thermal stress on glutamic acid metabolism in aspergillus fumigatus

C-Glutamic acid was metabolized in the fungus cultivated at 45 degree mostly into methionine, asparagine, cysteine alpha-amino adipic acid, glutamine and cysteine as well as several other amino acids. It was metabolized mainly into serine, glycine, cysteine, asparagine, arginine, alpha-amino adipic acid, cysteine and cystic acid at 30 degree. Proline and glutamine were detected only at 45 degree, while ornithine, arginine and alanine were metabolized only at 30 degrees. Marked quantities of labeled amino acids synthesized from the metabolized 14 C-glutamic acid were incorporated into fungal proteins

Selenium volatilization by a strain of fusarium

Fusarium sp. was isolated from Sinai soil in Egypt. This organism tolerated high concentrations of selenium compounds up to 3.5% [w/v]. The fungus released considerable quantities of dimethylselenide into the atmosphere. The biological release depended basically on several factors: incubation temperature, pH and substrate concentration. Maximum volatilization was obtained at 30 degree, a pH range of 6-7 and 1% [w/v] sodium selenite

Effects of halothane, enflurane and fentanyl anesthesia and surgery on serum concentrations of free thyroxin and tri iodothyronine

The effects of halothane, enflurane and fentanyl anaesthesia on fT3 and fT4 measured by RIA, were studied on 30 patients submitted to minor surgical procedures of the extremities. Patients were divided into three equal groups of 10 patients each. The effect of surgery was also studied on another 10 patients submitted to abdominal surgery. Halothane, enflurane and surgical manipulations caused significant increase of fT4 while fentanyl caused a mild insignificant increase. On fT3 all anaesthetics caused insignificant decrease while with surgery the decrease was significant. Therefore, the effects of these anaesthetics and surgery should be considered in cases of suspected thyroid malfunction

Reflux and stricture formation following translation ureter sigmoidostomy with submucous tunneling

20 renal units the ureters of which were transplanted into the sigmoid colon through a transcolonic approach using submucous tunnelling were fully evaluated 6 months postoperatively. Assessment of the results showed a low incidence of reflux due to the ample submucous tunnelling and a low incidence of stricture formation due to mucosa anastomosis and due to the avoidance of suturing in the formation of the submucous tunnel since sutures carry the potential risk of kinking and/or stenosing the ureter

Atracurium versus pancuronium in caesarean section

Atracurium has been shown to be a potent neuromuscular blocking agent with no cardiovascular side effects when used clinically effective doses, and to possess shorter duration of action. It was demonstrated that atracurium does not cross the placenta in clinically significant amounts. This work was carried out at the Saudi National Hospital on 40 patients presented for cesarean section. Patients were divided randomly into two groups to compare between atracurium and another conventional relaxant as pancuronium. It was revealed that atracurium in a dose of 0.2 mg/kg produced adequate surgical relaxation for a mean time of 21.4 minutes and incremental doses were needed in almost all cases. On the other hand, pancuronium mean time was 39.1 minutes and no incremental doses were required. Other criteria were mentioned in a comparative study