Myeloprotection with activated carbon in doxorubicin-treated rats.

Chemotherapy can often cause a variety of side effects including bone marrow (BM) suppression, termed as myelosuppression. Accordingly, facile and effective management of chemotherapy-induced myelosuppression is currently a pivotal task for experimental pathologists and oncologists. Here, we chose to use activated carbon (AC) with an extensive surface area for studying its possible protective effectiveness with respect to BM in doxorubicin (DOX)-treated rats.

Role of the Circadian Clock "Death-Loop" in the DNA Damage Response Underpinning Cancer Treatment Resistance.

Here, we review the role of the circadian clock (CC) in the resistance of cancer cells to genotoxic treatments in relation to whole-genome duplication (WGD) and telomere-length regulation. The CC drives the normal cell cycle, tissue differentiation, and reciprocally regulates telomere elongation. However, it is deregulated in embryonic stem cells (ESCs), the early embryo, and cancer.

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

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.

Tackling the acute radiation syndrome: Hemoperfusion with activated carbon revisited.

Almost three decades ago Dr. Nikolaev and co-authors reported a remarkable finding that a single-course low-volume hemoperfusion through uncoated spherical activated carbon led to a significant increase in survival of dogs acutely irradiated with X-rays of the dose of 5.25 Gy (Artif.

The effect of two formulations of carbon enterosorbents on oxidative stress indexes and molecular conformation of serum albumin in experimental animals exposed to CCl.

The liver failure means inability to perform its normal synthetic, biotransformation and excretory functions. The disturbance of metabolic processes leads to the development of "metabolic endogenous intoxication" resulting in oxidative stress. Oxidative stress initiates the processes of oxidation of amino acid residues of blood plasma proteins causing the changes in their structure and functions.

INDUCED POLYPLOIDY AND SORTING OF DAMAGED DNA BY MICRONUCLEATION IN RADIORESISTANT RAT LIVER EPITHELIAL STEM-LIKE CELLS EXPOSED TO X-RAYS.

Objective: Rat liver stem-like epithelial cells (WB-F344) that under certain conditions may differentiate into hepa- tocyte and biliary lineages were subjected to acute X-irradiation with the aim to examine cell cycle peculiarities dur- ing the course of survival.

Materials And Methods: Suspensions of WB-F344 cells that grew as a monolayer and reached sub-confluence were irradiated with 1, 5, and 10 Gy of X-rays (2 Gy/min). As an intact control, sham-irradiated cells were used.

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

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.

Densitometry of the optically magnified dried residues representing carbon microparticles as a simple and affordable technique for determining their concentrations in aqueous suspensions.

In extracorporeal blood purification, such as hemoperfusion, activated carbon (activated charcoal) beads are commonly used as an adsorbent, but their judgment in terms of extent of microparticle release is of great importance since the microparticles may represent the risk of entering the bloodstream. To quantitatively assess the release of carbon microparticles (CMPs) in the samples of the aqueous perfusion medium, in which the beads have been perfused, the calibration procedure with different concentrations of CMPs is likely to be needed. For this purpose, carbon beads were mechanically crushed to a fine powder, whose microparticles (<10 μm) were then serially diluted in the aqueous medium within the wide range of concentrations (0.

Disentangling the aneuploidy and senescence paradoxes: a study of triploid breast cancers non-responsive to neoadjuvant therapy.

Aneuploid cells should have a reduced proliferation rate due to difficulty in proceeding through mitosis. However, contrary to this, high aneuploidy is associated with aggressive tumour growth and poor survival prognosis, in particular in triploid breast cancer. A further paradox revolves around the observation that, while cell senescence should inhibit proliferation, the senescence marker p16INK4a correlates with poor treatment outcome in patients with a very aggressive triple-negative breast carcinoma (TNBC).

Role of stress-activated OCT4A in the cell fate decisions of embryonal carcinoma cells treated with etoposide.

Tumor cellular senescence induced by genotoxic treatments has recently been found to be paradoxically linked to the induction of "stemness." This observation is critical as it directly impinges upon the response of tumors to current chemo-radio-therapy treatment regimens. Previously, we showed that following etoposide (ETO) treatment embryonal carcinoma PA-1 cells undergo a p53-dependent upregulation of OCT4A and p21Cip1 (governing self-renewal and regulating cell cycle inhibition and senescence, respectively).

Characterization of breast cancer DNA content profiles as a prognostic tool.

Worldwide, breast cancer in women remains to be the most common malignancy that in a considerable proportion shows the resistance to genotoxic treatments and poor outcome. Chromosomal instability manifested as aneuploidy represents an integral cha-racteristics of the malignant genotype not only because of the selection of mutated aneuploid sub-clones that stipulate the tumor progression, but also because of the reversible endopolyploidy of tumor cells that serves for the endless maintenance of therapy-resistant tumor stem cells. Therefore, cytometric determination of DNA content in tissue samples for detecting malignancy, monitoring responses to therapy, and prognosing disease outcome needs to be revived.

Fractionated low-dose radiation exposure potentiates proliferation of implanted tumor cells.

Aim: The purpose of this study is to test whether whole-body fractionated exposure of tumor-free animals to low doses of low-LET radiation (at the total delivered dose of 1.0 Gy of X-rays) is capable of potentiating growth of subsequently implanted tumor cells.

Materials And Methods: Adult male rats were fractionally exposed to low doses of X-rays (10 acute exposures with 0.

Nitric oxide coordinates development of genomic instability in realization of combined effect with ionizing radiation.

Unlabelled: The aim of this study was to investigate the ability of environmental nitrogen oxides or natural nitric oxide (NO) donors to modify free radicals ba-lance and development of genomic instability alone or in combination with ionizing radiation.

Methods: Genotoxicity and cytogenetic abnormalities were assessed in vitro in peripheral blood lymphocytes (PBL) isolated from healthy humans or in vivo in rats PBL. Human PBL were treated with physiologically relevant NO donor - S-Nitrosoglutathione and X-ray irradiation.

The long-range cytotoxic effect in tumor-bearing animals.

Aim: The relationship between cancer and patient health is still of great interest for experimental and clinical oncology. The tumor can adversely affect surrounding and distant tissues as well. However, effects of the tumor on distant tissues are much less studied than its effects on surrounding tissues.

Hyperthermia alters the interaction of proteins of the Mre11 complex in irradiated cells.

Radiosensitization of mammalian cells by heat is believed to involve the inhibition of repair of DNA double-strand breaks (DSBs). The Mre11 complex (composed of Mre11, Rad50, and Nbs1) is involved in DSB repair and forms foci at sites of radiation-induced DSBs. Heat induces the translocation of a significant amount of Mre11, Rad50, and Nbs1 from the nucleus to the cytoplasm, but little is known about how heat affects the integrity of the proteins still remaining in nuclei, or alters kinetics of formation/disappearance of DNA repair foci in heated, irradiated cells.

At a crossroads of cancer risk and aging: the role of telomeres.

The risk of overall cancer inevitably increases with advancing age. The cancer incidence rate is not constant within the human life span (it exponentially increases with advancing age). Aging itself is a complex biological process with a poorly understood mechanism of its regulation.

Life cycle analysis of unicellular algae.

Unicellular green alga is a very convenient object for flow cytometric characterization. Flow cytometry has been proposed as a quick and reliable tool for studying life cycle and growth of unicellular algae. Cell size of vegetating algae can be monitored in association with their DNA and endogenous chlorophyll content.

A tool for enhancement and scoring of DNA repair foci.

Upon induction of DNA double-strand breaks (DSBs), Mre11 and Rad50 proteins of the Mre11 DNA repair complex accumulate at the sites of DSBs and form discrete nuclear foci. Precision in scoring of Mre11/Rad50-containing foci depends upon detection of those foci, some of which have a fluorescence staining intensity that is too close to the fluorescence staining intensity of the remaining Mre11 and Rad50 proteins that have not been incorporated into foci. Human U-1 melanoma cells in exponential growth were irradiated with various doses of X-rays (0-12 Gy) to induce the formation of repair foci.