Search results for "Chromosomes"

Preimplantation genetic diagnosis by fluorescence in situ hybridization: clinical possibilities and pitfalls.

2003

Preimplantation genetic diagnosis using the fluorescence in situ hybridization technique (FISH) is being used widely to prevent the transmission of sex-linked diseases, to screen for translocations, and for aneuploidy screenng in specific invitro fertilization (IVF) patient groups, along with FISH analysis of spematozoa in intertile men. In this study, we aim to critically analyze our clinical results in patients at risk of transmitting sex-linked diseases (n = 55), in carriers of translocations (n = 43), in women who have recurent miscarriage (two or more miscarriages) (n = 128), recurrent IVF failure (three or more failed IVF attempts) (n = 47), and patients of advanced maternal age (37 y…

Impact of chromosomal abnormalities on preimplantation embryo development.

2007

Objectives To evaluate the influence of numerical chromosomal abnormalities on preimplantation embryo development. Methods This study includes 6936 embryos from 1245 women undergoing preimplantation genetic diagnosis (PGD). Indications for aneuploidy screening were: recurrent miscarriages, implantation failure, severe male factor, advanced maternal age, and mixed causes. Embryo biopsy was performed on day 3, and embryos were co-cultured until day 5, when embryo transfer was performed. Results In the aneuploidy screening regimen, normal euploid embryos showed significantly higher blastocyst rates (68.2%) compared to chromosomally abnormal (42.8%, p < 0.0001) and mosaic (53.7%, p < 0.0001) em…

Cytogenetics, flow cytometry, cytophotometry and morphometry of 22 cases of primary breast carcinoma. A comparative study.

1992

Cytogenetic, flow cytometric, cytophotometric and morphometric analyses were performed on 22 previously untreated, primary solid breast carcinomas. Although the cell nuclei as the primary object of these studies were the same in all the tumors, distinct features were evaluated in each case to determine to what degree the results obtained by these techniques are comparable. From the cytogenetic viewpoint, six tumors had a modal number in the diploid range, seven were in the triploid range, and two in the tetraploid range; seven tumors had no modal number. These data correlate with the flow cytometry and cytophotometry results obtained, with DNA values slightly higher than their respective ch…

What can chromosomes tell us about the origin of primates?

2011

Apolipoprotein E polymorphism influences not only cerebral senile plaque load but also Alzheimer-type neurofibrillary tangle formation.

1995

Only recently, evidence was provided that apolipoprotein E allele epsilon 4 located on Chromosome 19 is associated with late onset (i.e. senile) sporadic Alzheimer's disease. Histologically, Alzheimer's disease is associated with intraneuronal neurofibrillary changes and extraneuronal A4/beta-amyloid deposition. We set out with a histological staging system which considers the gradual development of Alzheimer's disease-related histological changes over time and correlates highly with the cognitive decline ante mortem. Our analysis revealed that both the mean stage for A4/beta-amyloid deposits and the mean stage for neurofibrillary tangles get significantly shifted upwards in epsilon 4-carri…

Early induction of genetic instability and apoptosis by arsenic in cultured Chinese hamster cells

2002

In order to assess at what time from the beginning of exposure inorganic arsenic can give rise to genetic instability and trigger apoptosis, V79-C13 Chinese hamster cells were treated with 10 microM sodium arsenite for 24 h. Under these conditions, cell survival was >70% and cells showed neither an increase in chromosome aberration frequency nor a delay in cell cycle progression. Investigations, which were carried out every 6 h during the treatment, revealed an early appearance of genetically unstable cells, namely micronucleated, multinucleated and mononucleated 'giant' cells, as well as apoptotic cells. Indirect immunostaining using anti-beta-tubulin antibody showed severe alterations in …

Mitochondrial DNA Portrait of Latvians: Towards the Understanding of the Genetic Structure of Baltic-Speaking Populations

2005

Summary Mitochondrial DNA (mtDNA) variation was investigated in a sample of 299 Latvians, a Baltic-speaking population from Eastern Europe. Sequencing of the first hypervariable segment (HVS-I) in combination with analysis of informative coding region markers revealed that the vast majority of observed mtDNAs belong to haplogroups (hgs) common to most European populations. Analysis of the spatial distribution of mtDNA haplotypes found in Latvians, as well as in Baltic-speaking populations in general, revealed that they share haplotypes with all neighbouring populations irrespective of their linguistic affiliation. Hence, the results of our mtDNA analysis show that the previously described s…

Direct detection of repetitive, whole chromosome paint and telomere DNA probes by immunogold electron microscopy

1993

Biotinylated repetitive, whole chromosome paint and telomere DNA probes were investigated at the electron microscope level after non-isotopic in situ hybridization and direct immunogold detection. The protocol described allowed the visualization of a biotinylated chromosome 1 specific satellite DNA probe in the light microscope without silver intensification. This sensitive method was exploited to analyse factors contributing to signal strength in immunogold chromosome painting. Furthermore, it allowed us to investigate the distribution of (TTAGGG)n telomere repeats in human metaphase chromosomes and interphase nuclei. Telomeric and internal (TTAGGG)n repeats were detected at high spatial r…

Functional characterization of ORCTL2--an organic cation transporter expressed in the renal proximal tubules.

1998

AbstractChromosome 11p15.5 harbors a gene or genes involved in Beckwith-Wiedemann syndrome that confer(s) susceptibility to Wilms' tumor, rhabdomyosarcoma, and hepatoblastoma. We have previously identified a transcript at 11p15.5 which encodes a putative membrane transport protein, designated organic cation transporter-like 2 (ORCTL2), that shares homology with tetracycline resistance proteins and bacterial multidrug resistance proteins. In this report, we have investigated the transport properties of ORCTL2 and show that this protein can confer resistance to chloroquine and quinidine when overexpressed in bacteria. Immunohistochemistry analyses performed with anti-ORCTL2 polyc.onal antibod…

Elusive amines and cluster headache: mutational analysis of trace amine receptor cluster on chromosome 6q23.

2004

Cluster headache (CH) is characterised by unilateral pain and ipsilateral autonomic features. To date, no molecular genetic evidence has been shown for CH. Small pedigrees and low penetrance render the identification of the CH-gene quite difficult. Nonetheless the association of CH and migraine to a new class of amine, namely trace or elusive amines such as tyramine, octopamine and synephrine, has recently been demonstrated. In particular, in comparison to healthy control subjects, all these neurotransmitters have been found to be greatly elevated in CH sufferers in plasma and platelets both in active and remission periods. A cluster of gene-encoding G-protein-coupled receptors that bind an…