Mohamed Zaki

The aim of the present study was to enhance the dissolution rate of itraconazole (ITZ) by a simple solid dispersion method (melt method). Binary and ternary ITZ systems were prepared using different polymers including crystallization inhibiting polymers (Pluronic F68, Pluronic F127, Eudragit EPO, and polyvinyl pyyrolidone K25) at different ratios. The prepared solid

A marine exopolysaccharide (EPS) producing bacterium was isolated from a sponge sample at about 16 m depth in red sea (Huraghada, Egypt). Phenotypic characterization demonstrated that, the bacterium is a gram negative rod motile by means of single polar flagellum, showing wide range of carbohydrate utilization. Phylogenetic analysis based on 16S Ribosomal deoxyribonucleic acid (rDNA) sequence revealed 99% homology with Pseudoalteromonas sp., accordingly the name Pseudoalteromonas sp. AM was proposed. Maximum EPS productivity was achieved after 7 days at pH 7, agitation of 150 rpm in a fermentation medium containing glucose, meat extract

Background: To understand the complex and largely not well-understood apoptotic pathway and immune system evasion mechanisms in hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC) and HCV associated chronic hepatitis (CH), we studied the expression patterns of a number of pro-apoptotic and anti-apoptotic genes (Fas, FasL, Bcl-2, Bcl-xL and Bak) in HepG2 cell line harboring HCV- genotype-4 replication. For confirmation, we also assessed the expression levels of the same group of genes in clinical samples obtained from 35 HCC and 34 CH patients.

Stain etching of p-type silicon in hydrofluoric acid solutions containing nitric acid or potassium permanganate as an oxidizing agent has been examined. The effects of etching time, oxidizing agent and HF concentrations on the electrochemical behavior of etched silicon surfaces have been investigated byelectrochemical impedance spectroscopy (EIS). An electrical equivalent circuit was used for fitting the impedance data. The morphology and the chemical composition of the etched Si surface were studied using scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) techniques, respectively.

Plasma-cell Mastitis (Cheatle-Cutler's Disease of the Breast) is a rare but relatively important disease of the female breast. Because of its rarity it is poorly understood. It was first named by Cheatle and Cutler in tlheir book on 'Tumors of the Breast'. Adair was the first to call attention to its importance. These lesions may recur in the same or opposite breast. Their recurrence may take the original or a different form (e.g. a lobular plasma cell mastitis may recur as a contiguous multi-lobar plasma cell mastitis and vice versa). It may affect one breast and later appear in the opposite breast. Bilateral involvement has been reported.This lesion derives its importance from the fact that it has been repeatedly mistaken for breast carcinoma and has been treated as such.This mistake is liable to repeatedly occur again if frozen section biopsy of breast masses is neglected. I therefore report my clinical experience over a period of 43 years on this subject on the hope that clinical awareness will prohibit iatrogenic liabilities and errors.

We are concerned with linear and nonlinear multi-term fractional differential equations (FDEs). The shifted Chebyshev operational matrix (COM) of fractional derivatives is derivedand used together with spectral methods for solving FDEs. Our approach was based on theshifted Chebyshev tau and collocation methods.

The objective of the study was to determine the chemical composition and nutritional value of palm pollen grains. The proximate chemical composition, vitamin, mineral, amino acid and fatty acid contents of palm pollen grains were analyzed. The results obtained showed that the values of the proximate chemical composition of palm pollen grains were moisture (28.80%), ash (4.57%), crude fiber (1.37%), crude fat (20.74%), crude protein (31.11%) and carbohydrate (13.41%). Palm pollen grains contained a logical amount of vitamins A, E and C. They are a good source of minerals such as B, Zn, Se, Fe, Mo, Cu, Mn, Co and Ni. Leucine and lysine (3.34 and 2.95 g/100 g dry weight, respectively) were the major essential amino acid constituents. The predominant fatty acids of palm pollen grains were palmitic (C16:0), linoleic (C18:2) and myristic (C14:0) acids. In conclusion, palm pollen grains are a good economic nutritional source can be used as human food supplements.

Conducting polymers (CPs) are organic polymers that exhibit electronic, magnetic and optical properties of metals and semiconductors while retaining the attractive mechanical properties and processing advantages of polymers. These features, along with chemical sensitivity, room temperature operation, and tunable charge transport properties, have launched conducting polymers as a major class of chemical transducers, creating powerful thin/thick film sensors for over two decades. Additionally, their synthetic routes are compatible with several functionalization schemes, including covalent bonding to the monomer, entrapment during synthesis, and surface chemistry, which can impart a high degree of selectivity. CPs can be used as the selective layer in sensors (sensor receptor) or as the transducer itself. Physical transducers varying from optical, mass sensitive and electrochemical are all discussed in this chapter. In comparison with most of the commercially available sensors, based usually on metal oxides and operated at high temperatures, the sensors made of CPs have many improved characteristics. They have high sensitivities and short response time and more interestingly they work at room temperature. As a result, more and more attentions have been paid to the sensors fabricated from CPs.

A novel super absorbent polymer was prepared by graft copolymerization of 4-vinyl pyridine (4VP) onto the chain of carboxymethyl chitosan in aqueous solution using potassium persulphate (KPS) as initiator. The effect of monomer and initiator concentration,

Approaches for the preparation of azaenamines as well as the chemical reactivity profiles and structures of these substances are reviewed. Emphasis is given to the use of these substances as C-nucleophiles in the synthesis of five- and six-membered heterocycles and fused derivatives.

Enaminone 1 was reacted with hydrazonoyl halides 2a-d to yield 3,4-disubstituted pyrazoles 6a-d and coupling with arenediazonium chlorides to afford the 2-(arylhydrazono)-3-(1-naphthalenyl)-3-oxopropionaldehydes 13a-c. Compounds 13 could be utilized for synthesis of variety of arylpyrazoles, arylazolopyrimidines, and pyridazinones via reaction with hydrazines, aminoazoles, and active methylene derivatives, respectively. The foregoing reactions were carried out with chitosan as basic ecofriendly catalyst under conventional heating as well as pressurized microwave irradiation and a comparative study was employed.