Photocatalytic degradation of mono-and di-sulfonic acid dyes on iron and copper modified MCM-41 and Y Zeolites

The photocatalytic degradation of mono- and di-sulfonic acid dyes [Acid yellow 99] and [Acid Red 44] were investigated in an aqueous medium using iron and copper modified MCM-41 and Y zeolites. The substrate for each was chosen as a simple model for the study of reactions involving some complex commercial products used for the dyeing of textile fibers. The decrease in concentration of both acid dyes was followed spectrophotometrically. The results obtained revealed that the different investigated catalytic systems, in presence of H[2]O[2], as oxygen carrier material enhanced the photocatalytic degradation process. However, the catalytic activity of Cu-modified MCM-41 system was bigger than those measured for the other catalytic systems. It has been found that the degradation process depends mainly on the generated OH radicals from irradiated H[2]O[2], because the catalyst alone has no effect

Effect of nigella sativa crude oil skin penetration and viability of schistosoma mansoni cercariae

Nigella sativa crude oil directly tested in different concentrations on viable cercarial suspension is found to have direct lethal effect, even in high dilutions on cercariae. Histological studies revealed that Nigella sativa oil locally painted on the skin completely prevents cercarial penetration while food oil slightly decreases and delays it compared with the non painted control group. Whereas, unexpectedly skin painting with vaseline markedly increases cercarial motility and skin penetration. Local painting of the skin with Nigella sativa oil initiates a massive local immune response presented by increased number of mast cells

Homograft teeth for ossicular reconstruction in tympanoplasty [experimental study]

Various materials have been used in ossiculoplasty but no single material have been found to be completely satisfactory. Homograft and autograft middle ear ossicles and even mastoid cortical bone have been widely used in tympanoplasty. Animal work was conduct to study the reaction to homograft teeth when implanted intratympanic and subcutaneously. There were no macroscopic changes or rejection with follow up for one month. Microscopic examination revealed moderate cellular inflammatory changes with some foreign body giant cells, but there was no fragmentation of the implanted material or engulfing by giant cell. Also, mild degenerative changes were observed in small areas of the teeth in some animals. These reactions are comparable with that of the bioinert aluminium oxide ceramic implanted intratympanic in experimental animals 1 to 3 months postoperatively. Thus, homograft teeth seem to satisfy the criteria of a material to be used in tympanoplasty. Besides, it is easily available, durable and costless. Larger series with longer follow up is recommended