The Dumbo rat possesses some characteristics that evoke several human syndromes, such as Treacher-Collins: shortness of the maxillary, zygomatic and mandibular bones, and low position of the ears. Knowing that many homeobox genes are candidates in craniofacial development, we investigated the involvement of the Msx1 and Dlx1 genes in the Dumbo phenotype with the aim of understanding their possible role in abnormal craniofacial morphogenesis and examining the possibility of using Dumbo rat as an experimental model for understanding abnormal craniofacial development. We studied the expression of these genes during craniofacial morphogenesis by RT-PCR method. We used Dumbo embryos at E12 and E14 and included the Wistar strain as a control. Semi-quantitative PCR analysis demonstrated that Msx1 and Dlx1 are expressed differently between Dumbo and Wistar rats, indicating that their low expression may underly the Dumbo phenotype.

Bacterial strains isolated from water samples from Laguna Verde, Potosi-Bolivia and deposited at Biotechnology Center, Cochabamba-Bolivia, were subjected to lipolytic enzyme production studies. Among these, 10 strains were selected as positive in lipolytic enzyme production in solid medium, using olive oil as sole carbon source. Selected strains were subjected to morphological and biochemical studies. Enzyme production in liquid medium identified strain LV01 as the best enzyme producer with 0.079 U/ml lipolytic activity. Partial purification by ion-exchange chromatography of the lipolytic enzyme, produced by strain LV01, presented specific enzyme activity of 0,138 U/mg of eluted protein with approximately 77 KDa size. Partial characterization of the produced enzyme revealed its display maximum activity values at pH 9, 30°C y 1.7M NaCl , thus exhibiting remarkably haloalkalitolerant properties. The 16S rDNA gene sequence analysis showed 99% similarity between strain LV01 and Bacillus pumilus (embAJ494727)