Morphometric evaluation of nucleolar organizer regions in cervical intraepithelial neoplasia.

The objective of this study was to determine whether some morphometric parameters and two different methods of counting AgNOR dots were correlated with the grade of cervical intraepithelial neoplasia. Thirty uterine cervix biopsies (8 cases of cervicitis, 9 CIN I, CIN II and 6 CIN III) were studied. Two methods were used to count AgNOR dots. The first one consisted of counting the number of epithelial cells with 1, 2, 3, 4, or more dots. The second method, based on a computer analysis system, consisted of counting the total number of dots in 100 cells, without considering the number of dots per cell. Using the same computer analysis system, the following parameters were measured: area, diameter, perimeter, roundness and length of each dot. The following parameters were found to be correlated with the grade of intraepithelial neoplasia: 1) number of cells with 1 dot, which decreased with increasing grade of cervical intraepithelial neoplasia; 2) number of cells with 4 dots or more, which increased with increasing grade of cervical intraepithelial neoplasia; 3) total number of dots per 100 cells, which progressively increased with increasing grade of intraepithelial neoplasia. We conclude that counting cells with 4 or more dots is the more trustworthy parameter for distinguishing the grade of cervical intraepithelial neoplasia.

Cryopreservation of nucellar cells of navel orange (Citrus sinensis Osb. var. brasiliensis Tanaka) by vitrification.

The nucellar cells of navel orange(Citrus sinensis Osb. var. brasiliensis Tanaka) were successfully cryopreserved by vitrification. In this method, cells were sufficiently dehydrated with highly concentrated cryoprotective solution(PVS2) prior to direct plunge in liquid nitrogen. The PVS2 contains(w/v) 30% glycerol, 15% ethylene glycol and 15% DMSO in Murashige-Tucker medium(MT) containing 0.15 M sucrose. Cells were treated with 60% PVS2 at 25°C for 5 min and then chilled PVS2 at 0°C for 3 min. The cell suspension of about 0.1 ml was loaded in a 0.5 ml transparent plastic straw and directly plunged in liquid nitrogen for 30 min. After rapid warming, the cell suspension was expelled in 2 ml of MT medium containing 1.2 M sucrose. The average rate of survival was about 80%. The vitrified cells regenerated plantlets. This method is very simple and the time required for cryopreservation is only about 10 min.

Litiase experimental em ratos: papel da hidroclortiazida e de antibioticos na sua prevencao. / Experimental lithiasis in rats: the role of hydrochlorothiazide and antibiotics in its prevention

A etiologia dos calculos associados a presenca de corpo estranho nao e bem conhecida e, no sentido de elucidar melhor esse fenomeno, os autores utilizaram o modelo experimental proposto por Vermeulen.Placas de zinco foram aplicadas na bexiga de 48 ratos Wistar e estes foram divididos em 3 grupos experimentais: grupo A animais controles; grupo B, animais tratados com hidroclortiazida oral; grupo C, animais tratados com tetraciclina oral. Apos 6 semanas, os animais foram sacrificados colhendo-se material da bexiga para estudo bacteriologico e pesando-se os calculos presentes no local. A analise da media dos pesos dos calculos encontrados nestes animais nao demonstrou diferenca estatisticamente significante entre as mesmas, indicando que a formacao de calculos na presenca de corpo estranho nao depende da saturacao local de calcio e nem da existencia de infeccao urinaria