A preliminary study about the ultrastructural changes in the fibroblasts according to the cultivation time

The authors examined the ultrastructural changes in the fibroblasts of the embryos of chicken in a monolayer cultivation in relation to the cultivation time. Without changing cultivation medium, observations were made after 24 hr, 48 and 96 hr. After 24 hr, it was seen that the ultrastructure of the fibroblasts in the chicken embryos looks like ultrastructure of the fibroblasts of a normal human being. After 48 hr, many more vesicles showing a lysosome character than in the observations made after 24 hr were seen in the cytoplasm of the cultivated fibroblasts. After 96 hr of cultivation the cytoplasm of the cells showed a very large number of vacuoles of different sizes. The observations made with an electron microscope confirmed the large number of cells at that time of the cultivation. The ultrastructural changes appearing at the different cultivation times are in relation with the normal physiological death of the cells. (Journal received: 17th May, 1974

Selective Control of Polyamide Dyeing with Acid Dyes Using Hydroxypropyl-β-cyclodextrin

e effect of hydroxypropyl-β-cyclodextrin (HPβCD) in the dyeing of polyamide fabric was investigated under conditions that mimic industrial dyebaths where dye mixtures are used. The dyes used were Telon Red BN, Telon Yellow A-2R, and Telon Blue RR. The blue dye complexed with HPβCD whereas the other dyes did not do so under the conditions used. The dyeing results were compared with those obtained using a traditional retarding agent, Albegal B. The exhaustion dyeing data showed that HPβCD mainly affected the dyeing behavior of the blue dye that became encapsulated. In the case of the yellow and red dyes, changes in the overall kinetics of dyeing were observed, resulting in modified exhaustion profiles. In comparison, Albegal B retarded the blue dyeing process and increased the rate of exhaustion of the yellow dye while the exhaustion curve of red dye remained unchanged. The color uniformity of the dyed polyamide was improved when HPβCD was used. This resulted from the more controlled exhaustion rate during the critical phase of the dyeing process.National Science and Technology Foundation (FCT) through Project No. PEst-C/CTM/UI0264/2011.FEDER through Programa Operacional Factores de Competitividade - COMPET