MutSβ-MutLβ-FANCJ axis mediates the restart of DNA replication after fork stalling at cotranscriptional G4/R-loops.

Transcription-replication conflicts (TRCs) induce formation of cotranscriptional RNA:DNA hybrids (R-loops) stabilized by G-quadruplexes (G4s) on the displaced DNA strand, which can cause fork stalling. Although it is known that these stalled forks can resume DNA synthesis in a process initiated by MUS81 endonuclease, how TRC-associated G4/R-loops are removed to allow fork passage remains unclear. Here, we identify the mismatch repair protein MutSβ, an MLH1-PMS1 heterodimer termed MutLβ, and the G4-resolving helicase FANCJ as factors that are required for MUS81-initiated restart of DNA replication at TRC sites in human cells.

Isoelectric focusing followed by affinity immunoblotting to detect monoclonal free light chains in monoclonal gammopathies: Comparison with immunofixation electrophoresis and free light chain ratio.

Background: Isoelectric focusing (IEF) is a method with an exquisite resolution, and coupled with affinity immunoblotting (AIB), it can provide superior sensitivity to detect monoclonal free light chains (FLC).

Methods: We tested the hypothesis that IEF/AIB is more sensitive and specific for monoclonal FLC detection in serum and urine samples than conventional methods, that is, electrophoresis (ELP), immunofixation (IF) and serum FLC ratio assessment. Investigation included 107 samples of 68 patients, among which 21 multiple myeloma patients were recently tested for minimal residual disease and 18 patients with AL amyloidosis.

Chelators as Antineuroblastomas Agents.

Neuroblastoma represents 8-10 % of all malignant tumors in childhood and is responsible for 15 % of cancer deaths in the pediatric population. Aggressive neuroblastomas are often resistant to chemotherapy. Canonically, neuroblastomas can be classified according to the MYCN (N-myc proto-oncogene protein) gene amplification, a common marker of tumor aggressiveness and poor prognosis.

Recognition and coacervation of G-quadruplexes by a multifunctional disordered region in RECQ4 helicase.

Biomolecular polyelectrolyte complexes can be formed between oppositely charged intrinsically disordered regions (IDRs) of proteins or between IDRs and nucleic acids. Highly charged IDRs are abundant in the nucleus, yet few have been functionally characterized. Here, we show that a positively charged IDR within the human ATP-dependent DNA helicase Q4 (RECQ4) forms coacervates with G-quadruplexes (G4s).

Distinguishing Healthy and Carcinoma Cell Cultures Using Fluorescence Spectra Decomposition with a Genetic-Algorithm-Based Code.

In this paper, we analysed the steady state fluorescence spectra of cell suspensions containing healthy and carcinoma fibroblast mouse cells, using a genetic-algorithm-spectra-decomposition software (GASpeD). In contrast to other deconvolution algorithms, such as polynomial or linear unmixing software, GASpeD takes into account light scatter. In cell suspensions, light scatter plays an important role as it depends on the number of cells, their size, shape, and coagulation.

Coxsackievirus B4 sewage-isolate induces pancreatitis after oral infection of mice.

Numerous serotypes which belong to the genus Enterovirus (EV) show variability in their virulence and clinical manifestations. They are also known to undergo changes caused by mutations and recombination during their circulation in the environment and the population. Various EV serotypes are prevalent in groundwater, wastewater and surface waters.

RAD51-dependent recruitment of TERRA lncRNA to telomeres through R-loops.

Telomeres-repeated, noncoding nucleotide motifs and associated proteins that are found at the ends of eukaryotic chromosomes-mediate genome stability and determine cellular lifespan. Telomeric-repeat-containing RNA (TERRA) is a class of long noncoding RNAs (lncRNAs) that are transcribed from chromosome ends; these RNAs in turn regulate telomeric chromatin structure and telomere maintenance through the telomere-extending enzyme telomerase and homology-directed DNA repair. The mechanisms by which TERRA is recruited to chromosome ends remain poorly defined.

Hyaluronic acid chloramide-Synthesis, chemical structure, stability and analysis of antimicrobials.

Electron-deficient chlorine covalently immobilised on an amido group of hyaluronic acid (HA) can be potentially exceptional for applications requiring biodegradable and biocompatible polymers with enhanced antibacterial or antiviral activity. This expectation is supported by the assumption that a small amount of HA chloramide (HACl) is formed in the extracellular matrix under inflammatory conditions by a reaction of endogenous HA with hypochlorous acid (HClO) generated by a myeloperoxidase/HO/Cl system. HACl synthesis optimisation showed significant limitations of HClO as an oxidative agent where only lower degrees of substitution (DS) was achieved.

Murine experimental models for studying the pathogenesis of coxsackieviruses.

Understanding the pathogenesis of communicable diseases often involves animal models. Mouse models are studied by researchers to achieve a better understanding of the relationship between the biological, physiochemical, and antigenic properties of the infectious agent, as well as the histopathological, immunological, and functional changes in the living system and the target organs, in short, the pathophysiological processes that the communicable agents bring about. The long-term objectives of the in vivo studies are important from a medical point of view, as they represent faithful (reliable and similar) human responses, which enhance the development of diagnostics, treatment, and measures for preventing the spread of the disease.

Repetitive Detection of Aromatic Hydrocarbon Contaminants with Bioluminescent Bioreporters Attached on Tapered Optical Fiber Elements.

In this study, we show the repetitive detection of toluene on a tapered optical fiber element (OFE) with an attached layer of TVA8 bioluminescent bioreporters. The bioluminescent cell layer was attached on polished quartz modified with (3-aminopropyl)triethoxysilane (APTES). The repeatability of the preparation of the optical probe and its use was demonstrated with five differently shaped OFEs.

Pancreas of coxsackievirus-infected dams and their challenged pups: A complex issue.

Enteroviral infections are frequent, often asymptomatic in humans and during gravidity. The present study is an extension of our previous investigations where we had shown pancreatitis in challenged pups of CVB4-E2-infected dams. Present investigation describes the effect of gestational infection with this virus on the pancreas of both dams and their challenged pups.

Novel quinazolin-4-one derivatives as potentiating agents of doxorubicin cytotoxicity.

We report the design, synthesis and biological evaluation of 17 novel 8-aryl-2-morpholino-3,4-dihydroquinazoline derivatives based on the standard model of DNA-PK and PI3K inhibitors. Novel compounds are sub-divided into two series where the second series of five derivatives was designed to have a better solubility profile over the first one. A combination of in vitro and in silico techniques suggested a plausible synergistic effect with doxorubicin of the most potent compound 14d on cell proliferation via DNA-PK and poly(ADP-ribose) polymerase-1 (PARP-1) inhibition, while alone having a negligible effect on cell proliferation.

Purin-6-one and pyrrolo[2,3-d]pyrimidin-4-one derivatives as potentiating agents of doxorubicin cytotoxicity.

Aim: DNA damage response plays an eminent role in patients' response to conventional chemotherapy and radiotherapy. Its inhibition is of great interest as it can overcome cancer cell resistance and reduce the effective doses of DNA damaging agents. Results & methodology: We have focused our research on phosphatidylinositol 3-kinase-related kinases and prepared 35 novel compounds through a scaffold hopping approach.

Optimization of cell growth on palmitoyl-hyaluronan knitted scaffolds developed for tissue engineering applications.

Polysaccharides meet several criteria for a suitable biomaterial for tissue engineering, which include biocompatibility and ability to support the delivery and growth of cells. Nevertheless, most of these polysaccharides, for example dextran, alginate, and glycosaminoglycans, are highly soluble in aqueous solutions. Hyaluronic acid hydrophobized by palmitic acid and processed to the form of wet-spun fibers and the warp-knitted textile scaffold is water non-soluble, but biodegradable material, which could be used for the tissue engineering purpose.

Small molecule inhibitors of DNA-PK for tumor sensitization to anticancer therapy.

The most sensitive cell structure - a DNA molecule, is the common target of cancer therapy. DNA damage response (controlled by enzymes from the phosphatidylinositol 3-kinase-related kinases family - PIKK) presents many encouraging targets for improving both conventional cytotoxic anticancer therapy and individualized monotherapy. DNA-dependent protein kinase (DNA-PK) is a member of the PIKK superfamily and plays an important role in the detection and repair of DNA double-strand breaks via the non-homologous end-joining pathway.

Fabrication of biodegradable textile scaffold based on hydrophobized hyaluronic acid.

In this work, we report on the preparation of a novel biodegradable textile scaffold made of palmitoyl-hyaluronan (palHA). Monofilament fibres of palHA with a diameter of 120μm were prepared by wet spinning. The wet-spun fibres were subsequently processed into a warp-knitted textile.

Fiber-Optic Chemical Sensors and Fiber-Optic Bio-Sensors.

This review summarizes principles and current stage of development of fiber-optic chemical sensors (FOCS) and biosensors (FOBS). Fiber optic sensor (FOS) systems use the ability of optical fibers (OF) to guide the light in the spectral range from ultraviolet (UV) (180 nm) up to middle infrared (IR) (10 μm) and modulation of guided light by the parameters of the surrounding environment of the OF core. The introduction of OF in the sensor systems has brought advantages such as measurement in flammable and explosive environments, immunity to electrical noises, miniaturization, geometrical flexibility, measurement of small sample volumes, remote sensing in inaccessible sites or harsh environments and multi-sensing.

Speech changes after coordinative training in patients with cerebellar ataxia: a pilot study.

Although rehabilitative training is a necessary adjunct in the management of gait ataxia, it remains unknown whether the possible beneficial effect of intensive coordinative training may translate to activities of daily living, which are closely connected with postural alignment. The aim of the present study was to examine the effectiveness of a 2-week intensive coordinative motor training on speech production. Speech and motor performances in a cohort of ten individuals with cerebellar degeneration were examined three times; before the introduction of training, directly and 4 weeks after the last training session.

Micellar electrokinetic chromatography with short-end injection for rapid separation and simultaneous determination of aesculin, aesculetin, and phenylephrine in pharmaceutical preparations.

A fast micellar electrokinetic chromatography (MEKC) method for simultaneous assay of aesculin, aesculetin, and phenylephrine was developed and validated. The separation was carried out in a fused-silica capillary (50 μm id, total length 64.5 cm, effective length 8.

Effects of sphingomyelin/ceramide ratio on the permeability and microstructure of model stratum corneum lipid membranes.

The conversion of sphingomyelin (SM) to a ceramide (Cer) by acid sphingomyelinase (aSMase) is an important event in skin barrier development. A deficiency in aSMase in diseases such as Niemann-Pick disease and atopic dermatitis coincides with impaired skin barrier recovery after disruption. We studied how an increased SM/Cer ratio influences the barrier function and microstructure of model stratum corneum (SC) lipid membranes.

Determination of phenolic acids in plant extracts using CZE with on-line transient isotachophoretic preconcentration.

A novel transient ITP-CZE for preconcentration and determination of seven phenolic acids (caffeic acid, cinnamic acid, p-coumaric acid, ferulic acid, protocatechuic acid, syringic acid, and vanilic acid) was developed and validated. Effects of several factors such as control of EOF, pH and buffer concentration, addition of organic solvents and CDs, and conditions for sample injection were investigated. Sample self-stacking was applied by means of induction of transient ITP, which was realized by adding sodium chloride into the sample.

Fiber-optic pH detection in small volumes of biosamples.

Determining the pH values of microscopic plant samples may help to explain complex processes in plants, so it is an area of interest to botanists. Fiber-optic probes with small dimensions can be used for this purpose. This paper deals with the fiber-optic detection of the pH values of droplets of plant xylem exudate based on ratiometric fluorescence intensity measurements with an internal reference.

Preparation and characterization of polymethacrylate monolithic capillary columns with dual hydrophilic interaction reversed-phase retention mechanism for polar compounds.

Monolithic columns for capillary hydrophilic interaction liquid chromatography (HILIC) were prepared in fused-silica capillaries by radical co-polymerization of [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide and ethylene dimethacrylate in various binary and ternary porogen solvent mixtures with azobisisobutyronitrile as the initiator of the polymerization reaction. Columns showed mixed separation modes: reversed-phase (RP) in water-rich mobile phases and HILIC at high concentrations of acetonitrile (>60-80%) in aqueous-organic mobile phases. A continuous change in retention was observed at increasing concentration of water in acetonitrile, giving rise to characteristic U-turn plots of retention factors versus the concentration of water in the mobile phase, with minima corresponding to the transition between the mechanisms controlling the retention.

Use of molybdate as novel complex-forming selector in the analysis of polyhydric phenols by capillary zone electrophoresis.

Molybdate was examined as a complex-forming additive to the CE background electrolytes (BGE) to affect the selectivity of separation of polyhydric phenols such as flavonoids (apigenin, hyperoside, luteolin, quercetin and rutin) and hydroxyphenylcarboxylic acids (ferulic, caffeic, p-coumaric and chlorogenic acid). Effects of the buffer concentrations and pH and the influence of molybdate concentration on the migration times of the analytes were investigated. In contrast to borate (which is a buffering and complex-forming agent generally used in CE at pH > or =9) molybdate forms more stable complexes with aromatic o-dihydroxy compounds and hence the complex-formation effect is observed at considerably lower pH.