Mohamed D.,Applied Research Sector |
Elsayed I.,Cairo University |
Elsayed I.,Gulf Medical University |
Mohamed A.F.,Applied Research Sector |
Yehia S.A.,Cairo University
Drug Development and Industrial Pharmacy | Year: 2015
To test if trehalose could be a better cryoprotectant for BCG than the usually used lactose and predict viability of BCG during shelf-life, BCG was suspended into three stabilizer systems containing 15% w/v trehalose, trehalose-gelatin mixture (in ratio, 30: 1 w/w) or lactose. Each formula was lyophilized and several quality parameters were tested before and after lyophilization including sterility, safety, viability, morphology and moisture content. Samples of lyophilized formulae were tested for their reconstitution time and others were charged to stability chambers at 5°C for the performance of real time study. Shelf-life of each formula was estimated and correlation between moisture content and loss in viability was established at each time interval of the real time stability study. Sterility, safety and morphology were retained after lyophilization. Just after lyophilization, minute diminish in viability was observed in the presence of each stabilizer (0.02-0.05%). There was no significant difference in reconstitution time of the three lyophilized formulae. Lactose BCG had the highest shelf-life among the used cryoprotectants during the real time stability studies. Also, moisture content was highly correlated to viability with correlation coefficient ranged between 0.97 and 0.99 and so, the former could be used for prediction of viability throughout the vaccine shelf-life. © 2015 Informa Healthcare USA, Inc.
Angkawijaya A.E.,National Taiwan University of Science and Technology |
Fazary A.E.,King Khalid University |
Fazary A.E.,Applied Research Sector |
Hernowo E.,National Taiwan University of Science and Technology |
And 2 more authors.
Journal of Solution Chemistry | Year: 2012
Binary and mixed-ligand complexes of Ni2+ and Co2+ involving L-norvaline (Nva) and ferulic acid (FA) have been investigated in aqueous solutions by pH potentiometry and UV-visible spectrophotometric techniques, at 298.15 K and fixed ionic strength (0.15 moldm3, NaNO3). The overall stability constants of the Ni2+ and Co2+ complexes with the ligands studied were obtained by the HYPERQUAD2008 program from the pHpotentiometric data. As a result of the numerical treatment, a model composed of seven species NiNva+, NiNva2, NiNvaH1, NiNva- 2, NiFA, NiFAH- 1 and NiNvaFA was obtained for the Ni2+ + Nva + FA system, whereas for the Co2+ + Nva + FA system the complexes CoNva+, CoNva2 , CoNvaH1, CoNvaH- 2, CoFA, CoFAH- 1, and CoNvaFA were obtained. The complex species distributions in certain pH ranges were calculated by the HySS2009 simulation program. Spectroscopic UV-visible measurements were carried out to give qualitative information about the complexes formed in these solutions. © Springer Science+Business Media, LLC 2012.
Abbas S.Y.,National Research Center of Egypt |
Farag A.A.,Taif University |
Farag A.A.,Al - Azhar University of Egypt |
Ammar Y.A.,Al - Azhar University of Egypt |
And 4 more authors.
Monatshefte fur Chemie | Year: 2013
New series of Schiff's bases, hydrazones, thiosemicarbazones, thiazoles, and thiocarbohydrazones of 5-fluoroisatin were synthesized by the reaction of 5-fluoroisatin with primary amines, hydrazine hydrate, and thiocarbohydrazides. Thiosemicarbazones were prepared by reacting hydrazone derivatives with isothiocyanates. Upon treatment of thiosemicarbazone derivatives with chloroacetone, the thiazole derivatives were obtained. Some of the prepared compounds exhibited antiviral activity. © Springer-Verlag Wien 2013.
Tohamy A.A.,Helwan University |
Fahmy A.M.,Applied Research Sector |
Dkhil M.A.,Helwan University |
Dkhil M.A.,King Saud University |
Diab M.S.M.,Helwan University
African Journal of Biotechnology | Year: 2010
Rabies remains an important public health problem in the world due to uncontrolled enzootic rabies, lack of safe efficient vaccines and poor information on the risk of contracting rabies post animal exposure. The lethality and mutagenic potential of challenge virus standard (CVS) was evaluated in mice. Mice were intracerebrally infected (MIC) with low, medium and high viral LD50 (MICLD50). Mice were subjected to immunomodulation using interferon (IFNα-2a) pre- infection. The infected groups pretreated with IFN-α 2a showed a higher survival rate than the infected group. Statistically significant increase in structural and numerical chromosomal aberrations and a decreased mitotic activity of mice bone marrow cells was observed post infection. Pretreatment of the infected groups with IFN α-2a showed a marked and significant reduction of these cytogenetic changes. The increased survival rate and reduced cytogenetic changes suggest that protection induced by interferon against rabies virus activity could be, at least partially, attributable to blockage of the replication of CVS strain of rabies virus. It could be concluded that interferon can be used as an immune enhancer to the application of vaccine administration. © 2010 Academic Journals.