820 results match your criteria: "General Physics Institute[Affiliation]"

In this study, we have investigated the surface-enhanced Raman scattering (SERS) spectra of myoglobin on silver substrates with different morphology. The aim was to determine the optimal parameters of analyte and substrate preparation for obtaining of high-amplitude SERS spectra of proteins. It is shown that not only the morphology of the silver film, but also the method of analyte molecules deposition on the SERS substrate plays an important role.

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Modern radiotherapy utilizes a broad range of sources of ionizing radiation, both low-dose-rate (LDR) and high-dose-rate (HDR). However, the mechanisms underlying specific dose-rate effects remain unclear, especially for corpuscular radiation. To address this issue, we have irradiated human epidermoid carcinoma A431 cells under LDR and HDR regimes.

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A novel approach to developing lateral flow assays (LFAs) for the detection of CYFRA 21-1 (cytokeratin 19 fragment, a molecular biomarker for epithelial-origin cancers) is proposed. Magnetic bioconjugates (MBCs) were employed in combination with advanced optical and magnetic tools to optimize assay conditions. The approach integrates such techniques as label-free spectral-phase interferometry, colorimetric detection, and ultrasensitive magnetometry using the magnetic particle quantification (MPQ) technique.

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Two platinide plumbides, EuPtPb and SrPtPb, were discovered using high-temperature exploratory synthesis and flux-assisted crystal growth. Their crystal structures were determined from single-crystal X-ray diffraction. Both compounds crystallize in the orthorhombic system; EuPtPb belongs to the YRhSn structure type (2, = 4.

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  • Strontium-barium niobate (SrBaNbO) films are promising for microwave applications due to their high dielectric nonlinearity and low losses.
  • The films were synthesized on sapphire substrates using magnetron sputtering, and their structural features were analyzed through various methods, focusing on Brillouin light scattering.
  • Brillouin light scattering proved to be an effective nondestructive technique for examining the films' structures, allowing precise determination of their thickness and unique properties influenced by acoustic wave scattering.
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The problem of treating cancer patients with lung cancer has become more difficult due to the SARS-CoV-2 viral infection and concomitant bacterial lesions. The analysis shows that the photodynamic effect of long-wavelength polycationic photosensitizers suppresses the tumor process (including the destruction of cancer stem cells), SARS-CoV-2 coronavirus infection, Gram-positive and Gram-negative bacteria, including those that can cause pneumonia. Therefore, the photodynamic approach using such photosensitizers is promising for the development of an effective treatment method for patients with lung cancer, including those with SARS-CoV-2 infection and bacterial complications.

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The present study aims to understand the molecular mechanism underlying the therapeutic effect of cerium nanoparticles (CeNPs) in oncology. Cancer cells were treated with different concentrations of pure nanocerium of different sizes synthesized by laser ablation. Due to the not insignificant influence of surface defects and oxygen species on the ROS-modulating properties of cerium nanoparticles, the nanoparticles were not coated with surfactants or organic molecules during synthesis, which could potentially inhibit a number of pro-oxidative effects.

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  • * This study developed and characterized iron nanoparticles doped with selenium (FeNP@SeNPs) to explore their effects on the calcium signaling system in astrocytes under ischemia-like conditions.
  • * The research found that combining magnetic selenium nanoparticles with electromagnetic stimulation enhances cell penetration and facilitates endocytosis through TRPV4 channel activation, allowing for a reduced effective concentration compared to traditional selenium nanoparticles.
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: High-grade gliomas remain a virtually incurable form of brain cancer. Current therapies are unable to completely eradicate the tumor, and the tumor cells that survive chemotherapy or radiation therapy often become more aggressive and resistant to further treatment, leading to inevitable relapses. While the antiproliferative effects of new therapeutic molecules are typically the primary focus of research, less attention is given to their influence on tumor cell migratory activity, which can play a significant role in recurrence.

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Despite progress in the high-pressure synthesis of nanodiamonds from hydrocarbons, the problem of controlled formation of fluorescent impurity centers in them still remains unresolved. In our work, we explore the potential of a new precursor composition, a mixture of adamantane with detonation nanodiamond, both in the synthesis of nanodiamonds and in the controlled formation of negatively charged silicon-vacancy centers in such nanodiamonds. Using different adamantane/detonation nanodiamond weight ratios, a series of samples was synthesized at a pressure of 7.

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This study presents the development of stannous chloride (SnCl)-modified glass substrates for biomolecule immobilization and their application in fabricating sensor chips for label-free interferometric biosensors. The glass modification process was optimized, identifying a 5% SnCl concentration, a 45 min reaction time, and a 150 °C drying temperature as conditions for efficient protein immobilization. Based on the SnCl-modified glass substrates and label-free spectral-phase interferometry, a biosensor was developed for the detection of aflatoxin B1 (AFB1)-a highly toxic and carcinogenic contaminant in agricultural products.

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Aging presents a significant challenge to health and social care systems due to the increasing proportion of the elderly population. The identification of reliable biomarkers to assess the progression of aging remains an unresolved question. Circular RNAs (circRNAs) are single-stranded covalently closed RNAs.

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Dangling bonds (DBs) are common defects in silicon that affect its electronic performance by trapping carriers at the in-gap levels. For probing the electrical properties of individual DBs, a scanning tunneling microscope (STM) is an effective instrument. Here we study transitions between charge states of a single DB on chlorinated and brominated Si(100)-2 × 1 surfaces in an STM.

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The development of various nanomaterials production technologies has led to the possibility of producing nanoparticles (NPs) and nanostructures, which can find a wide range of applications, from the fabrication of microelectronic devices to the improvement of material properties and the treatment of cancer. The unique characteristics of nanoparticles are primarily due to their small size, which makes size control important in their preparation. Modification of nanoparticles by laser irradiation and obtaining desired nanoparticle properties is a promising approach because of its ease of implementation.

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Precise control of cellular temperature at the microscale is crucial for developing novel neurostimulation techniques. Here, the effect of local heat on the electrophysiological properties of primary neuronal cultures and HEK293 cells at the subcellular level using a cutting-edge micrometer-scale thermal probe, the diamond heater-thermometer (DHT), is studied. A new mode of local heat action on a living cell, thermal-capture mode (TCM), is discovered using the DHT probe.

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Mitochondrial damage and associated oxidative stress are considered to be major contributory factors in cardiac pathology. One of the most potent naturally occurring antioxidants is taxifolin, especially in its water-soluble form. Herein, the effect of a 14-day course of the peroral application of the water-soluble taxifolin (aqTAX, 15 mg/kg of body weight) on the progression of ultrastructural and functional disorders in mitochondria and the heart's electrical activity in a rat model of myocardial injury induced with isoprenaline (ISO, 150 mg/kg/day for two consecutive days, ) was studied.

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The use of metal and metal oxide nanoparticles is frequently regarded as a potential solution to the issue of bacterial antibiotic resistance. Among the proposed range of nanoparticles with antibacterial properties, copper oxide nanoparticles are of particular interest. Although the antibacterial properties of copper have been known for a considerable period of time, studies on the effects of copper oxide nanomaterials with respect to biological systems have attracted considerable attention in recent years.

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Development of new antibacterial materials for solving biomedical problems is an extremely important and very urgent task. This review aims to summarize recent articles (from the last five and mostly the last three years) on the nanoparticle/polymer composites for biomedical applications. Articles on polymeric nanoparticles (NPs) and hydrogel-based systems were not reviewed, since we focused our attention mostly on the composites of polymeric matrix with at least one inorganic filler in the form of NPs.

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Targeted drug delivery for primary brain tumors, particularly gliomas, is currently a promising approach to reduce patient relapse rates. The use of substitutable scaffolds, which enable the sustained release of clinically relevant doses of anticancer medications, offers the potential to decrease the toxic burden on the patient's organism while also enhancing their quality of life and overall survival. Upconversion nanoparticles (UCNPs) are being actively explored as promising agents for detection and monitoring of tumor growth, and as therapeutic agents that can provide isolated therapeutic effects and enhance standard chemotherapy.

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Different types of photosensitizers (PSs) have different dynamics and intensities of accumulation, depending on the type of tumor or different areas within the same tumor. This determines the effectiveness of fluorescence diagnostics and photodynamic therapy (PDT). This paper studies the processes of 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) and chlorin e6 (Ce6) accumulation in the central and border zones of a tumor after combined administration of two PSs into the patient's body.

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Article Synopsis
  • Lung cancer is a major global health issue, influenced by cancer stem cells (CSCs), but the interaction between these CSCs and SARS-CoV2 is not well understood.
  • This study compares lung adenocarcinoma samples from 12 patients who had COVID-19 with 12 who did not, examining tumor characteristics and CSC markers.
  • Results indicated that patients who had COVID-19 had significantly more CSCs (marked by ALDH1, CD133, and CD34) in their tumors, suggesting that COVID-19 may enhance the metastatic potential of lung adenocarcinoma and the presence of viral proteins in the lung tissue.
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  • There is a rising interest in using titanium dioxide nanoparticles (TiO NPs) as antimicrobial agents due to their strong activity against bacteria and fungi, along with their low toxicity and high biocompatibility.
  • The review examines factors affecting TiO NPs' effectiveness, including size, shape, composition, microbial type, and synthesis methods, noting that smaller particles generally show better antibacterial properties.
  • It highlights that amorphous TiO NPs and those doped with inorganic compounds exhibit the best antimicrobial potential, emphasizing the diverse methodologies in synthesizing and analyzing these nanoparticles.
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Current bounds on the neutrino Majorana mass are affected by significant uncertainties in the nuclear calculations for neutrinoless double-beta decay. A key issue for a data-driven improvement of the nuclear theory is the actual value of the axial coupling constant g_{A}, which can be investigated through forbidden β decays. We present the first measurement of the 4th-forbidden β decay of ^{115}In with a cryogenic calorimeter based on indium iodide.

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Introduction: The process of forming selenium nanoparticles with various shapes and structures through laser ablation and fragmentation in various solvents has been explored.

Methods: Laser ablation and laser fragmentation techniques were employed using nanosecond Nd:YAG second harmonic laser irradiation in 9 different working fluids, including water. The characteristics of the resulting nanoparticles were assessed using transmission electron microscopy (TEM), dynamic light scattering (DLS), spectroscopy, and X-ray diffraction (XRD) methods.

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  • * Raman spectroscopy is highlighted as an effective method for monitoring changes in the structure of these glycol solutions over time, especially how water content decreases on substrates.
  • * The study also reveals that the water content reduction affects the presence of certain molecular conformations in the glycols and demonstrates that a specific laser wavelength (1064 nm) is effective for analyzing antifreeze products containing dyes.
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