introduction: the purpose of this study was to evaluate the sealing ability of 3 obturation techniques in oval-shaped canals by bacterial leakage assessment. methods: sixty mandibular incisors with oval canals were selected after providing buccolingual and mesiodistal radiographs. the teeth were sectioned at a 10 mm distance from the apex. after instrumentation, the teeth were divided into 3 gr...

The present study was undertaken to provide more information on the density and distribution of heterochromatin in early and advanced stages of the granulocytic, lymphocytic and erythroid development. Heterochromatin was visualized using a simple cytochemical method for the demonstration of DNA followed by computer-assisted densitometry of the digitized images. The largest heterochromatin densi...

The RNA-induced silencing complex (RISC) or the RISC complex mediates RNAi and is comprised of proteins belonging to the dicer and Argonaute family proteins. Here we show that Argonaute-2 (ago-2) is required for proper nuclear migration, pole cell formation, and cellularization during the early stages of embryonic development in Drosophila. We have traced these defects back to the nuclear divis...

Genome organization within the cell nucleus is a result of chromatin condensation achieved by histone tail-tail interactions and other nuclear proteins that counter the outward entropic pressure of the polymeric DNA. We probed the entropic swelling of chromatin driven by enzymatic disruption of these interactions in isolated mammalian cell nuclei. The large-scale decondensation of chromatin and...

A 26-year-old woman had a 4-day history of fever, aches, and throat irritation. She had tender right posterior cervical lymphadenopathy and mild hepatosplenomegaly. Her hemoglobin was 12.6 g/dL, white blood count 5.5 109/L with relative lymphocytosis (58%), and platelet count 100 109/L. The peripheral smear showed reactive lymphocytes with rare (1%) apoptotic lymphocytes (top left panel shows a...

Changes in the peripheral distribution and amount of condensed chromatin are observed in a number of diseases linked to mutations in the lamin A protein of the nuclear envelope. We postulated that lamin A interactions with nuclear envelope transmembrane proteins (NETs) that affect chromatin structure might be altered in these diseases and so screened thirty-one NETs for those that promote chrom...

Xenopus egg extracts initiate DNA replication specifically at the dihydrofolate reductase (DHFR) origin locus with intact nuclei from late G1-phase CHO cells as a substrate, but at nonspecific sites when purified DNA is assembled by the extract into an embryonic nuclear structure. Here we show that late G1-phase CHO nuclei can be cycled through an in vitro Xenopus egg mitosis, resulting in the ...

Incubation of demembranated sperm chromatin in cytoplasmic extracts of unfertilized Xenopus laevis eggs resulted in nuclear envelope assembly, chromosome decondensation, and sperm pronuclear formation. In contrast, egg extracts made with EGTA-containing buffers induced the sperm chromatin to form chromosomes or irregularly shaped clumps of chromatin that were incorporated into bipolar or multip...

We have investigated both the K and K0 condensations in -equilibrated neutron star (NS) matter using the relativistic mean-…eld model with the renormalized meson-baryon coupling constants. Adopting the antikaon optical potential of 120MeV, our model predicts the K condensation as the second-order phase transition inside the neutron star of maximum mass, while the deeper potential than 160MeV is...