Physical Fundamentals of Biomaterials Surface Electrical Functionalization

2020

This article is focusing on electrical functionalization of biomaterial&rsquo

Differential staining of peripheral nuclear chromatin with Acridine orange implies an A-form epichromatin conformation of the DNA

2018

ABSTRACT The chromatin observed by conventional electron microscopy under the nuclear envelope constitutes a single layer of dense 30–35 nm granules, while ∼30 nm fibrils laterally attached to them, form large patches of lamin-associated domains (LADs). This particular surface “epichromatin” can be discerned by specific (H2A+H2B+DNA) conformational antibody at the inner nuclear envelope and around mitotic chromosomes. In order to differentiate the DNA conformation of the peripheral chromatin we applied an Acridine orange (AO) DNA structural test involving RNAse treatment and the addition of AO after acid pre-treatment. MCF-7 cells treated in this way revealed yellow/red patches of LADs atta…

<title>Multiparameter breast cancer cell image analysis for objective estimation of nuclear grade: comparison with light microscopic observatio…

2000

We performed a multi parameter image analysis assessment of breast cancer cell population nuclear grade (NG), which is regarded as one of the main prognostic factors for treatment efficacy and survival of the patients and compared it with light microscopic estimation of NG. Cytological imprint slides from 20 ductal carcinomas were stained according to Leischmann-AzureII-eosine method, and NG was estimated by light microscopic observation according to Black in Fisher's modification. Simultaneously, using specially elaborated software, in each patient 100 cancer cells were analyzed for nuclear perimeter, diameter, area, nucleolar area, and average intensity of staining. The chromatin structur…

When Three Isn't a Crowd: A Digyny Concept for Treatment-Resistant, Near-Triploid Human Cancers.

2019

Near-triploid human tumors are frequently resistant to radio/chemotherapy through mechanisms that are unclear. We recently reported a tight association of male tumor triploidy with XXY karyotypes based on a meta-analysis of 15 tumor cohorts extracted from the Mitelman database. Here we provide a conceptual framework of the digyny-like origin of this karyotype based on the germline features of malignant tumors and adaptive capacity of digyny, which supports survival in adverse conditions. Studying how the recombinatorial reproduction via diploidy can be executed in primary cancer samples and HeLa cells after DNA damage, we report the first evidence that diploid and triploid cell sub-populati…

Heterochromatin Networks: Topology, Dynamics, and Function (a Working Hypothesis)

2021

Open systems can only exist by self-organization as pulsing structures exchanging matter and energy with the outer world. This review is an attempt to reveal the organizational principles of the heterochromatin supra-intra-chromosomal network in terms of nonlinear thermodynamics. The accessibility of the linear information of the genetic code is regulated by constitutive heterochromatin (CHR) creating the positional information in a system of coordinates. These features include scale-free splitting-fusing of CHR with the boundary constraints of the nucleolus and nuclear envelope. The analysis of both the literature and our own data suggests a radial-concentric network as the main structural…

The nuclear envelope-associated epichromatin and its sheets are composed of DNA A-form packed as nucleosomal superbeads which construct vehicles for …

2019

Toluidine Blue Test for Sperm DNA Integrity and Elaboration of Image Cytometry Algorithm

2003

Background: Sperm DNA integrity is of paramount importance in the prognosis of fertility. We applied image cytometry to a toluidine blue (TB) test we recently proposed. Methods: Sperm samples from 33 men were assayed for standard sperm parameters and classified as normal or abnormal. Sperm smears were subjected to the TB test, DNA denaturation testing with acridine orange (AO), and terminal deoxyuridine triphosphate biotin nick end labeling (TUNEL). In CCD image analysis, TB-stained sperm cell heads were microscopically assigned to one of four color groups (dark, blue, light violet, and light blue). The optical densities of 6,600 cells in green and red CCD images were used to elaborate an a…

Properties of erythrocyte light refraction in diabetic patients.

2001

Since hyperglycaemia changes the erythrocyte cell membrane fluidity and impairs cell deformity, our goal was to characterize hemoglobin and red blood cell (RBC) light refractive property changes in diabetic patients. Microscopic investigation was carried out on intact and fixed RBCs. To determine the refractive index (RI): smears of peripheral blood were air dried and fixed for 3 min in methanol. Mixtures of polyvinylpyrolidine and buffer of different pH (1:1) were used as embedding media. Intact RBCs were mixed with a buffered embedding medium, placed on a slide and overlaid with a coverslip. Interference microscopy was used for RI measurements at 18 different pH (pH=2-13). The results sho…

<title>Influence of strong static magnetic field on human cancer HT 1080 cells</title>

2001

The aim of this study was to investigate strong uniform magnetic field influence on the human cancer cells HT 1080. The cells were treated with magnetic field of intensity 1,16 Tesla and with anticancer agent - cis-platinum 0.025 mg/ml or vincristinum 2-3 ng/ml. The intact and the treated cell samples were incubated in a medium with acridine orange (AO). The magnetic field after 15 minutes of influence significantly increased cytoplasmic red fluorescence. Increased AO accumulation in lysosomes suggested to cancer cell metabolic activity stimulation.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Differentiating cancer cells reveal early large-scale genome regulation by pericentric domains.

2021

Abstract Finding out how cells prepare for fate change during differentiation commitment was our task. To address whether the constitutive pericentromere-associated domains (PADs) may be involved, we used a model system with known transcriptome data, MCF-7 breast cancer cells treated with the ErbB3 ligand heregulin (HRG), which induces differentiation and is used in the therapy of cancer. PAD-repressive heterochromatin (H3K9me3), centromere-associated-protein-specific, and active euchromatin (H3K4me3) antibodies, real-time PCR, acridine orange DNA structural test (AOT), and microscopic image analysis were applied. We found a two-step DNA unfolding after 15–20 and 60 min of HRG treatment, re…

Influence of hydrogen-ion concentration on refractive index value in red blood cells of diabetes patients

2002

Since hyperglycaemia changes fluidity of erythrocyte cell membrane and impair cell deformability, our goal was to characterize light refractive properties of haemoglobin and red blood cells (RBC) in diabetes patients. Microscopic investigation was carried out on intact and in methanol fixed RBCs of diabetes patients with long-term hyperglycaemia (glycosylated haemoglobin > 7,5%). Interference microscopy was used for refractive index (RI) measurements at 18 different pH levels in range of 2 - 13. Results showed that the curves of RI in intact and fixed cells of diabetes patients and fixed cells for control group were of similar configuration, with one branch in alkaline portion, one branch i…

<title>Refractive properties of separate erythrocytes of Chernobyl clean-up workers at different pH</title>

2000

This study is focused on the modifications in erythrocytes of Chernobyl nuclear power plant accident clean-up workers as a late health effect of short-term impact of high level radioactive contamination. As a result, a new method based on erythrocyte (RBC) refractive index properties at different pH has been elaborated. According to the light dispersion theory for fluids refractive index is associated with molecules mass m. This feature is widely used for estimation of cell dry mass. But there is another refractive index dependency from molecules charge q regardless of its sing. This feature is not being used for cell quantitative and qualitative characterization. In this study, RBC were in…

Differential staining of peripheral nuclear chromatin with Acridine orange implies an A-form epichromatin conformation of the DNA

2018

The chromatin observed by conventional electron microscopy under the nuclear envelope constitutes a single layer of dense 30–35 nm granules, while ∼30 nm fibrils laterally attached to them, form large patches of lamin-associated domains (LADs). This particular surface “epichromatin” can be discerned by specific (H2A+H2B+DNA) conformational antibody at the inner nuclear envelope and around mitotic chromosomes. In order to differentiate the DNA conformation of the peripheral chromatin we applied an Acridine orange (AO) DNA structural test involving RNAse treatment and the addition of AO after acid pre-treatment. MCF-7 cells treated in this way revealed yellow/red patches of LADs attached to a…