Amyloid-beta peptide (25-35) triggers a reorganization of lipid membranes driven by temperature changes.

The amyloid-beta peptide (Aβ) is considered a key factor in Alzheimer's disease (AD) ever since the discovery of the disease. The understanding of its damaging influence has however shifted recently from large fibrils observed in the inter-cellular environment to the small oligomers interacting with a cell membrane. We studied the effect of temperature on the latter interactions by evaluating the structural characteristics of zwitterionic phosphatidylcholine (PC) membranes with incorporated Aβ peptide.

Automation of single-cell proteomic sample preparation.

Molecular heterogeneity exists at different spatial scales in biological samples and is an important parameter in the development of pathologies and resistances to therapies. When aiming to reach molecular heterogeneity of cells at extremely low spatial scales, single-cell analysis can be the ultimate choice. Proteomics performed in bulk population of cells (macroproteomics) is prone to mask molecular heterogeneity.

A low-voltage electro-membrane extraction for quantification of imatinib and sunitinib in biological fluids.

Hollow-fiber-based supported liquid membrane was modified utilizing nanostructures such as graphite, graphene oxide or nitrogen-doped graphene oxide, for electro-membrane extraction (EME) of imatinib and sunitinib from biological fluids. By applying these conductive nanostructures, a low-voltage EME device (6.0 V) was fabricated.

Peroxide stimulated transition between the ferryl intermediates of bovine cytochrome c oxidase.

During catalysis of cytochrome c oxidases (CcO) several ferryl intermediates of the catalytic heme a-Cu center are observed. In the P ferryl state, produced by the reaction of two-electron reduced CcO with O, the ferryl iron of heme a and a free radical are present at the catalytic center. The radical reduction stimulates the transition of the P into another ferryl F state.

Molecular dynamics study of the competitive binding of hydrogen peroxide and water molecules with DNA phosphate groups.

The interaction of hydrogen peroxide molecules with the DNA double helix is of great interest for understanding the mechanisms of anticancer therapy utilising heavy ion beams. In the present work, a molecular dynamics study of competitive binding of hydrogen peroxide and water molecules with phosphate groups of the DNA double helix backbone was carried out. The system of DNA double helix in a water solution with hydrogen peroxide molecules and Na[Formula: see text] counterions was simulated.

Thermodynamics of the P-type Ferryl Form of Bovine Cytochrome c Oxidase.

Several ferryl states of the catalytic heme a-Cu center of the respiratory cytochrome c oxidases (CcOs) are observed during the reduction of O2 to H2O. One of the P-type ferryl forms, P, is produced by the reaction of the two-electron reduced CcO with O2. In this state, the heme a iron is in the ferryl state and a free radical should be also present at the catalytic center.

Nurses' Knowledge and Attitudes towards Prevention of Pressure Ulcers.

Background: Pressure ulcers (PU) remain a serious complication of immobile patients and a burden for healthcare professionals. The incidence and prevalence remain alarming. Knowledge and attitudes of nurses play a fundamental role in prevention.

Microproteomic sample preparation.

Multiple applications of proteomics in life and health science, pathology and pharmacology, require handling size-limited cell and tissue samples. During proteomic sample preparation, analyte loss in these samples arises when standard procedures are used. Thus, specific considerations have to be taken into account for processing, that are summarised under the term microproteomics (μPs).

Two-phase agarose gel-electromembrane extraction: Effect of organic solvent as an acceptor phase in electroendosmosis flow phenomenon.

In this study, a new mode of gel electromembrane extraction (G-EME) namely as "Two-phase G-EME", is suggested for the sensitive quantification of five basic drugs (desipramine, clomipramine, trimipramine, citalopram and clozapine) in biological samples. Compared to classical G-EME which is based on aqueous-gel-aqueous layout, herein, the aqueous acceptor phase (AP) was replaced with organic solvent. Briefly, negative electrode was immersed into the organic AP (with low conductivity) and positive electrode into the aqueous donor phase (DP).

An overview on the recent applications of agarose as a green biopolymer in micro-extraction-based sample preparation techniques.

Introducing a myriad array of chemicals in different industrial fields has made sample preparation inevitable for trace analysis. Classical extraction techniques such as solid phase extraction (SPE) and liquid-liquid extraction (LLE) techniques often suffer from tedious procedures (huge workload) and hazards to personnel and environment (samples and reagents are often user-unfriendly and processed in high amounts). For addressing these problems, microextraction techniques have been introduced.

Detection of organic dyes by surface-enhanced Raman spectroscopy using plasmonic NiAg nanocavity films.

This work presents the NiAg nanocavity film for the detection of organic dyes by surface-enhanced Raman spectroscopy (SERS). Nanocavity films were prepared by colloidal lithography using 518-nm polystyrene spheres combined with the electrochemical deposition of Ni supporting layer and Ag nanoparticles homogeneous SERS-active layer. The theoretical study was modelled by finite-difference time-domain (FDTD) simulation of electromagnetic field enhancement near the nanostructured surface and experimentally proven by SERS measurement of selected organic dyes (rhodamine 6G, crystal violet, methylene blue, and malachite green oxalate) in micromolar concentration.

What mental health experts in Slovakia are learning from COVID-19 pandemic?

Introduction: The COVID-19 pandemic was confirmed to have spread to Slovakia on 6th March 2020. To date of paper submission, it has very favorable course. However, since the beginning healthcare workers have been working under increasing pressure, anxiety and fear.

Recurring Asystole and Paradoxical Air Embolization in a Patient with a Patent Foramen Ovale Treated with Home Parenteral Nutrition.

Unlabelled: Home parenteral nutrition is a therapeutic option for chronic intestinal failure. A tunnelled central venous catheter is commonly used for self-application of nutrition and hydration over a long period of time; that is, months or years. Air embolization within the venous circulation can be caused by inconsistent self-handling of the catheter in combination with air bubbles in the infusion set.

Modulation of the electron-proton coupling at cytochrome a by the ligation of the oxidized catalytic center in bovine cytochrome c oxidase.

Cytochrome a was suggested as the key redox center in the proton pumping process of bovine cytochrome c oxidase (CcO). Recent studies showed that both the structure of heme a and its immediate vicinity are sensitive to the ligation and the redox state of the distant catalytic center composed of iron of cytochrome a (Fe) and copper (Cu). Here, the influence of the ligation at the oxidized Fe-Cu center on the electron-proton coupling at heme a was examined in the wide pH range (6.

Recent advances in robotic protein sample preparation for clinical analysis and other biomedical applications.

Discovery of new protein biomarker candidates has become a major research goal in the areas of clinical chemistry, analytical chemistry, and biomedicine. These important species constitute the molecular target when it comes to diagnosis, prognosis, and further monitoring of disease. However, their analysis requires powerful, selective and high-throughput sample preparation and product (analyte) characterisation approaches.

RHOA and mDia1 Promotes Apoptosis of Breast Cancer Cells Via a High Dose of Doxorubicin Treatment.

Background: Transforming RhoA proteins (RHOA) and their downstream Diaphanous homolog 1 proteins (DIAPH1) or mDia1 participate in the regulation of actin cytoskeleton which plays critical role in cells, i.e., morphologic changes and apoptosis.

Remote ischemic postconditioning as well as blood plasma from double-conditioned donor ameliorate reperfusion syndrome in skeletal muscle.

The aim of this study was to verify the possibility of preparation and effectiveness of the use of blood plasma containing an effector of ischemic tolerance activated by applying two sublethal stresses to a donor. As sublethal stresses, two periods of 20-minute hindlimb ischemia were used with a two-day interval between them. Active plasma was isolated six hours after the second hindlimb ischemia.

The Incidence of Pinworm () in Pre-school and School Aged Children in the Eastern Slovakia.

Helminth infections caused by have a cosmopolitan character and most often affect the paediatric pre-school and school age population. The presented study was conducted to determine the prevalence of in the analyzed population of children in the Eastern Slovakia. The Graham's scotch tape method was used to investigate the presence of eggs in 390 specimens.

Influence of a polymer membrane on the electrochemical determination of insulin in nanomodified screen printed carbon electrodes.

Diabetes mellitus can be considered one of the most widespread diseases globally. Hence, the diabetes research is currently focused on developing an effective, low-cost sensor having high stability and suitable analytical characteristics. Screen printed carbon electrodes (SPCEs) embody ideal candidates for insulin determination due to the small area of the working electrode eliminating the solution volume required for the given purpose.

Application of small-angle neutron diffraction to the localization of general anesthetics in model membranes.

We set out to explore the applicability of small-angle neutron diffraction (SAND) to the localization of biomembrane components by studying the general anesthetic n-decane in a model lipid bilayer system composed of dioleoyl-phosphocholine (DOPC). Samples in the form of planar membrane multilayers were hydrated by varied mixtures of deuterated and protonated water, and examined by the means of SAND. Neutron scattering length density (NSLD) profiles of the system were then reconstructed from the experimental data.

Noninvasive Assessment of Liver Fibrosis in Patients with Chronic Hepatitis B or C by Contrast-Enhanced Magnetic Resonance Imaging.

To develop a noninvasive magnetic resonance imaging (MRI) method for evaluation of liver fibrosis. We evaluate the utility of hepatocyte-phase Gadoxetate disodium-enhanced magnetic resonance (MR) imaging in staging hepatic fibrosis and compare it with histological analysis as the reference standard (liver biopsy). Prospective cohort of 78 patients, who received Gadoxetate disodium dynamic contrast-enhanced MRI (DCE-MRI), were divided into three groups.

In situ decomposition of deep eutectic solvent as a novel approach in liquid-liquid microextraction.

In this study, a novel approach for effective liquid-liquid microextraction based on deep eutectic solvent (DES) decomposition was suggested for the first time. It was established that DESs synthesized from tetrabutylammonium bromide and long-chain alcohols decomposed in aqueous phase resulting in in situ dispersion of organic phase and extraction of hydrophobic analyte(s). It this process long-chain alcohol acted as an extraction solvent and tetrabutylammonium bromide acted as a dispersive agent and promoted mass transfer between aqueous and organic phases as a salting out agent.

Evaluation of dispersive liquid-liquid microextraction by coupling with green-based agarose gel-electromembrane extraction: An efficient method to the tandem extraction of basic drugs from biological fluids.

Nowadays, developing new methods for the effective extraction/separation of drugs (present at trace levels) from complicated matrices (as biological fluids) is certainly a great challenge for many operators. In this regard, green-based agarose gel electromembrane extraction (G-EME) was for the first time combined with dispersive liquid-liquid microextraction (DLLME) toward G-EME/DLLME methodology (i.e.

The insomnia phenotype in genetic Creutzfeldt-Jakob disease based on the E200K mutation.

The aim of the presented study was to reveal the frequency of insomnia spells in E200K genetic Creutzfeldt-Jakob disease (gCJD) patients. Clinical records of 22 subjects diagnosed with E200K gCJD were retrospectively reviewed. The patients w/wo insomnia (n = 4, 18%/n = 18, 82%) did not differ in age, sex and the duration of the symptomatic phase.

The unfolded protein response controls endoplasmic reticulum stress-induced apoptosis of MCF-7 cells via a high dose of vitamin C treatment.

Recent in vitro studies have shown that vitamin C (Vit C) with pro-oxidative properties causes cytotoxicity of breast cancer cells by selective oxidative stress. However, the effect of Vit C in itself at different concentration levels on MCF-7 breast cancer cell line after 24 h, has not yet been described. We aimed to examine the effect of Vit C on the viability and signalling response of MCF-7/WT (MCF-7 wild-type) cells that were exposed to various concentrations (0.