human chromosomes in amnion cells and lymphocytes with normal karyotype and in lymphocytes with pathological karyotype (2n=47, +21) were compared as to their position in the metaphase. none of the collectives showed sex differences. measurement of the radial distances revealed more peripheral position of the majority of large chromosomes. the satellite-carrying chromosomes of the d group always...

Mitosis and male meiosis were studied in Myrmedobia coleoptrata (Fn.), (Heteroptera, Microphysidae). Spermatogonial metaphase revealed 14 chromosomes (2n=12 + XY). The nucleolar organizing region was found on the X chromosome. No m-chromosomes were present in the complement. Male meiotic prophase was characterized by a prominent condensation stage. At this stage, the sex chromosomes were positi...

Mitotic chromosome structure and DNA sequence requirements for normal chromosomal condensation remain unknown. We engineered labeled chromosome regions with altered scaffold-associated region (SAR) sequence composition as a formal test of the radial loop and other chromosome models. Chinese hamster ovary cells were isolated containing high density insertions of a transgene containing lac operat...

Mammalian mitotic chromosome morphogenesis was analyzed by 4D live-cell and snapshot deconvolution fluorescence imaging. Prophase chromosomes, whose organization was previously unknown, are revealed to comprise co-oriented sister linear loop arrays displayed along a single, peripheral, regularly kinked topoisomerase II/cohesin/condensin II axis. Thereafter, rather than smooth, progressive compa...

ChromoShake is a three-dimensional simulator designed to find the thermodynamically favored states for given chromosome geometries. The simulator has been applied to a geometric model based on experimentally determined positions and fluctuations of DNA and the distribution of cohesin and condensin in the budding yeast centromere. Simulations of chromatin in differing initial configurations reve...

Pre-metaphase stretch is a term first coined by the preeminent cell biologist Sally Hughes-Schrader in 1950 to describe an elongation of prometaphase chromosomes observed primary spermatocytes phasmid insects and praying mantids. Research from many groups since Hughes-Schrader’s initial observation has revealed reasons for both how why might elongate prior metaphase. In this review, we findings...

background:  the purpose of this study was to report the preoperative complaints and postoperative outcome of patients after removal of the radial head prosthesis.   methods:  this is a retrospective review of 14 adult patients (6 females and 8 males) from 2007 to 2011, who underwent radial head prosthesis removal by three surgeons. the average time between implantation and removal was 23 month...

A traditional karyomorphological approach was carried out in order to investigate the cytotaxonomic relationships among species of Santolina chamaecyparissus complex. All 14 included this complex were analysed for a total 39 populations. Metaphase plates obtained by squashing root tips stained with Feulgen technique. Measurable metaphase available literature also re-analysed. Chromosome number ...

Current models of mitotic chromosome structure are based largely on the examination of maximally condensed metaphase chromosomes. Here, we test these models by correlating the distribution of two scaffold components with the appearance of prophase chromosome folding intermediates. We confirm an axial distribution of topoisomerase IIalpha and the condensin subunit, structural maintenance of chro...