Enucleated halves of sea urchin eggs obtained by centrifugation contain almost all the mitochondrial population of the egg. Removal of the nucleus followed by parthenogenetic activation stimulates the incorporation of [3H]thymidine into the mitochondrial DNA, whereas no such incorportion is observed in activated whole eggs. The block is not the result of a modification in the permeability of th...

How would you best represent a high resolution original image given a fixed number of pixels for an image thumbnail? Is it possible to create better thumbnails than the standard computer-generated thumbnails that apply filtering and subsampling? In this report, these questions are addressed by manually generating thumbnails that attempt to well-represent the original high resolution images. Thu...

Invasive bacteria can induce their own uptake and specify their intracellular localization; hence it is commonly assumed that proximate modulation of host cell transcription is not required for infection. However, bacteria can also modulate, directly or indirectly, the transcription of many host cell genes, whose role in the infection may be difficult to determine by global gene expression. Is ...

The objective of the study was to characterize the ultrastructure changes and biochemical mechanisms underlying the expulsion of the entire chromosome complement in chemically enucleated mouse oocytes. The ultrastructural studies demonstrated that the morphology of cytoplasts produced by etoposide-cycloheximide treatment were indistinguishable from intact metaphase I and II oocytes. Moreover, p...

Cell infection with Trypanosoma cruzi, the agent of Chagas' disease, begins with the uptake of infective trypomastigotes within phagosomes and their release into the cytosol, where they transform into replicating amastigotes; the latter, in turn, differentiate into cytolytically released and infective trypomastigotes. We ask here if the T. cruzi infection program can develop in enucleated host ...

purpose : to compare the outcome of surgery and postoperative complications between using manually dissected cornea in descemet’s stripping with endothelial keratoplasty (dsek) and using eye bank automated precut cornea in descemet’s stripping with automated endothelial keratoplasty (dsaek) methods : forty eyes with indication of endothelial keratoplasty (ek) were included in this randomized pr...

A series of 30 enucleated eyes, all of which had a primary histological diagnosis of scleritis, was analysed. The average age of patients at enucleation was 68 years; many of these patients had had the disease for more than 30 years. In 40 per cent the diagnosis of scleritis was unsuspected and was often masked by multiple complications. Scleritis with uveitis and glaucoma was the most common c...

The enucleation technique has been applied to Amoeba proteus by several laboratories in attempts to determine whether the cytoplasm is capable of nucleus-independent ribonucleic acid synthesis. This cell is very convenient for micrurgy, but its use requires a thorough starvation period to eliminate the possibility of metabolic influence by food vacuoles and frequent washings and medium renewal ...

Transfusion of red blood cells (RBCs) is a standard and indispensable therapy in current clinical practice. In vitro production of RBCs offers a potential means to overcome a shortage of transfusable RBCs in some clinical situations and also to provide a source of cells free from possible infection or contamination by microorganisms. Thus, in vitro production of RBCs may become a standard proce...