The varying effects of a range of preservatives on Myoviridae and Siphoviridae bacteriophages formulated in a semi-solid cream preparation.

Bacteriophages may be formulated into semi-solid bases for therapeutic delivery. This work investigated the effects of a range of preservatives on the viability of Myoviridae and Siphoviridae bacteriophages when these were formulated into a standard semi-solid cream base. The six preservatives tested included: benzoic acid (0·1%), chlorocresol (0·1%), combination hydroxybenzoates (propyl 4-hydroxybenzoates with methyl 4-hydroxybenzoates) (0·1%), methyl 4-hydroxybenzoate (0·08%), 2-phenoxyethanol (1%) and propyl 4-hydroxybenzoate (0·02%). These were each formulated into cetomacrogol cream aqueous to generate six individual semi-solid bases into which Myoviridae and Siphoviridae bacteriophages were added and tested for stability. Optimal bacteriophage stability was seen when the preservative chlorocresol was used. Bacteriophage in the acidic benzoic acid were the least stable, resulting in complete loss of viability after 4-5 weeks. Of the bacteriophages tested, the Myoviridae KOX1 was significantly more stable than the Siphoviridae PAC1 after 91 days in formulations with each of the preservatives. Our results suggest the need for individual testing of specific bacteriophages in pharmaceutical formulations, as their efficacy when exposed to preservatives and excipients in these delivery forms may vary. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteriophages are being increasingly investigated as alternatives to antibiotics. While bacteriophages can be formulated in diverse ways for therapeutic delivery, there has been scant work on how excipients and preservatives in these formulations affect stability of different bacteriophages. We demonstrate that the nature of preservatives in formulations will affect bacteriophage stability, and that in these formulations, viability of bacteriophage differs according to their morphology. Our work highlights the need for individual testing of specific bacteriophages in pharmaceutical formulations, as efficacy when exposed to preservatives and excipients in these delivery forms may vary.

Application of Ultraviolet-C Light on Storage Rots and Ripening of Tomatoes.

The application of ultraviolet light (UV-C, 254 nm) hormesis on fruits and vegetables to stimulate beneficial responses is a new method for controlling storage rots and extending the shelf-life of fruits and vegetables. The present study was aimed at treating tomatoes ( Lycopersicon esculentum ) with different UV-C dosages (1.3 to 40 KJ/m2) to induce resistance to black mold ( Alternaria alternata ), gray mold ( Botrytis cinerea ), and Rhizopus soft rot ( Rhizopus stolonifer ). These diseases were effectively reduced when tomatoes were inoculated following UV-C irradiation. UV-C treated tomatoes were firmer in texture and less red in color than the control tomatoes, indicating a delay in ripening. Slower ripening and resistance to storage rots of tomatoes are probably related. The positive effect of UV-C on tomatoes decreased as treatments were performed at stages of increased ripeness.

Les lesions tubaires et peritoneales a la coelioscopie chez les femmes steriles aux Cliniques Universitaires de Kinshasa

Les 434 cas de coelioscopie diagnostique pour sterilite pratiquee aux Cliniques Universitaires de Kinshasa du 1er Aout 1988 au 31 juillet 1992 font l'objet d'une etude retrospective pour apprecier l'importance des differentes lesions tubo-peritoneales et leurs etiologies. Les obstructions tubaires distales sont deux fois et demi plus frequentes que les obstructions tubaires (OT) proximales; qui predominent chez les epouses des polygames. Les Obstructions tubaires distales et les adherences pelviennes sont plus frequentes chez les femmes avec antecedents de chirurgie gynecologique pelvienne. La frequence des cas d'endometriose pelvienne est de 6;4 pour cent. A part les maladies sexuellement transmissibles qui sont souvent evoquees comme cause; la chirurgie pelvienne semble etre egalement a la base de ces lesions