The Spemann organizer secretes several antagonists of growth factors during gastrulation. We describe a novel secreted protein, Mig30, which is expressed in the anterior endomesoderm of the Spemann organizer. Mixer-inducible gene 30 (Mig30) was isolated as a target of Mixer, a homeobox gene required for endoderm development. The Mig30 gene encodes a secreted protein containing a cysteine-rich d...

Tissue markers of cellular proliferatian have been recently utilized as prognostic indicators in brain tumors. Nudeolar organizer regions (NORs)are loops of deoxyribonudeic add (DNA) that transcribe to ribosomal ribonudeic acid (RNA) by RNA polymerase i. Using asilver staining technique. nudeolar organizer region-assodated proteins (AgNORs) have been studied in paraffin sections of 62 meningeal...

Silver staining at the electron microscopic level of the nucleolar organizers was carried out on Xenopus laevis oocytes at various stages of oogenesis. The results indicate that a positive reaction takes place exclusively in the dense fibrillar component of the extrachromosomal nucleoli. This constituent undergoes morphological changes of distribution and architecture, which have been correlate...

Cytogenetics studies in 12 specimens of Gymnothorax ocellatus reveled a diploid chromosome number of 2n 42 (16 metacentrics, 18 submetacentrics and 8 acrocentrics). The nucleolar organizer regions were located in a terminal position on the long arm of the chromosome pair number fifteen. Conspicuous blocks of constitutive heterochromatin were observed in the centromeric and pericentromeric regio...

Cytogenetic studies were carried out on samples of Parapteronotus hasemani, Sternarchogiton preto and Sternarchorhamphus muelleri (Apteronotidae, Gymnotiformes) from the Amazon basin. The first two species exhibited both a 2n = 52 karyotype, but differed in their karyotypic formulae, distribution of constitutive heterochromatin, and chromosomal location of the NOR. The third species, Sternarcho...

One of the biggest challenges in studying how genes work is understanding their effect on the physiology and anatomy of the body. Existing tools try to address this using indirect features, such as expression levels and biochemical pathways. Here, we present Gene ORGANizer (geneorganizer.huji.ac.il), a phenotype-based tool that directly links human genes to the body parts they affect. It is bui...

We study the power of a tournament organizer in manipulating the outcome of a balanced single-elimination tournament by fixing the initial seeding. This problem is known as agenda control for balanced voting trees. It is not known whether there is a polynomial time algorithm that computes a seeding for which a given player can win the tournament, even if the match outcomes for all pairwise play...

Male students perform significantly lower than female students on tests that measure writing achievement. The purpose of this study was to explore the use of a visual graphic organizer application to engage elementary-aged male students who struggle with the writing process. The results suggest that teachers of male students should consider using a visual graphic organizer application for writi...

AIM   To clinically and histopathologically evaluate the anti-inflammatory effect of 0.2% hyaluronan gel alone and with mechanical therapy on gingivitis. The argyrophilic nucleolar organizer region staining technique was attempted to routinely determine its diagnostic and prognostic dependability for periodontal lesions. METHODS   In each of the 28 gingivitis patients, the four quadrants were...