Publications by authors named "Alexandrov M"

Background: Сervicomedullary ependymoma (CME) is a rare tumor of the central nervous system. The CME treatment strategy is insufficiently represented in the literature and is a complex task for neurosurgeons.

Observations: The authors describe an infrequent case of a large multisegmental CME that extended from the medulla oblongata to the cervical spinal cord at the level of the sixth cervical vertebra in a 21-year-old female.

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Background: Chronic cerebral ischemia (CCI) is a form of cerebrovascular disease manifested as a vascular cognitive impairment (VCI). The management of the patients with CCI is determined by a healthy lifestyle and early therapy aimed at correcting and preventing this disease. Divaza is a drug with endothelial protective and nootropic effects.

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Objective: The article demonstrates the experience of using laser fluorescence spectrometry (LFS) in the diagnosis of inflammatory diseases of pharynx, describes a method for recording spectra of pharyngeal tissues using the EnSpectr L405 hardware-software complex operating on the basis of laser radiation with a wavelength of 405 nm, and identifies characteristic features of spectral curves.

Patients And Methods: The authors presented the characteristics of the spectra from the surface of the pharynx tissue of healthy volunteers, patients with chronic tonsillitis and granular pharyngitis.

Results: The most informative parameters of the spectral curves were calculated, analyzing which it is possible to identify the morphometric, metabolic, functional features of the tissue of the tonsils and posterior pharyngeal wall in normal and pathological conditions.

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The Research Scanning Polarimeter (RSP) is an airborne along-track scanner measuring the polarized and total reflectances with high angular resolution. It allows for accurate characterization of liquid water cloud droplet sizes using the rainbow structure in the polarized reflectance. RSP's observations also provide constraints on the cumulus cloud's 2D cross section, yielding estimates of its geometric shape.

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Article Synopsis
  • The cloud droplet number concentration (N) is crucial for understanding cloud physics and aerosol-cloud interactions, but current satellite methods to retrieve N are limited and uncertain.
  • A review highlights a total relative uncertainty of 78% in pixel-level retrievals for specific cloud types, which decreases to 54% for larger area averages, but accuracy against in situ observations is better than indicated by retrievals.
  • Dominant errors in retrieving N stem from inaccuracies in cloud droplet effective radius (r), and improving these retrievals is essential; the review also suggests recommendations and explores new methods for better N estimates using both satellite and ground-based data.
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The objective of the research was to elaborate experimental-theoretical and clinic-bacteriological rationale for the application of laser diagnostic for identification of main pathogens of purulent-inflammatory processes in maxillofacial area. For germs identification by giant Raman scattering effect SERS-substrate with nano silver metallic balls, reference strains (Ps. aeruginosa 27853 and S.

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Changes of subjective and objective symptoms, elektroneyromiographic parameters, analysis of vegetative system were perfomed in 120 patients with diabetes mellitus type 2. The obtained results show the dependence of subjective and objective manifestations from the duration of the disease.

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There is a growing demand to develop biocontainment strategies that prevent unintended proliferation of genetically modified organisms in the open environment. We found that the hypophosphite (HPO, HPt) transporter HtxBCDE from Pseudomonas stutzeri WM88 was also capable of transporting phosphite (HPO, Pt) but not phosphate (HPO, Pi), suggesting the potential for engineering a Pt/HPt-dependent bacterial strain as a biocontainment strategy. We disrupted all Pi and organic Pi transporters in an Escherichia coli strain expressing HtxABCDE and a Pt dehydrogenase, leaving Pt/HPt uptake and oxidation as the only means to obtain Pi.

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We present, for the first time, a quantitative retrieval error-propagation study for a bistatic high spectral resolution lidar (HSRL) system intended for detailed quasi-global monitoring of aerosol properties from space. Our results demonstrate that supplementing a conventional monostatic HSRL with an additional receiver flown in formation at a scattering angle close to 165° dramatically increases the information content of the measurements and allows for a sufficiently accurate characterization of tropospheric aerosols. We conclude that a bistatic HSRL system would far exceed the capabilities of currently flown or planned orbital instruments in monitoring global aerosol effects on the environment and on the Earth's climate.

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Possible application is studied for fluorescence spectroscopy in the express-evaluation of the gastrointestinal microflora. This diagnostic approach is feasible because of the difference in fluorescent spectra from different microorganisms, with anaerobic microorganisms exhibiting the most pronounced fluorescence. It was found that fluorescence strength raised with an increase in the bacteria Bacteroides and bifid bacteria, whereas it decreased with an increase in Escherichia coli.

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Considering the increasing use of various asbestos substitutes, asbestos risk management in many industries may require accurate techniques for detecting and distinguishing asbestos from non-asbestos fibers. Using fluorescently labeled asbestos-binding proteins, we previously developed a novel method for detection and counting of asbestos fibers under fluorescence microscopy (FM). This method can provide speedy, on-site detection and identification of the asbestos fibers and has higher sensitivity than phase contrast microscopy (PCM).

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A large number of peptides with binding affinity to various inorganic materials have been identified and used as linkers, catalysts, and building blocks in nanotechnology and nanobiotechnology. However, there have been few applications of material-binding peptides in the fluorescence microscopy-based biosensing (FM method) of environmental pollutants. A notable exception is the application of the FM method for the detection of asbestos, a dangerous industrial toxin that is still widely used in many developing countries.

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Article Synopsis
  • A new model for aerosol optical thickness (AOT) variability is introduced, treating AOT fields as realizations of a stochastic process rooted in a Gaussian process with a specific autocorrelation function.
  • The model provides lognormal probability distribution functions (PDFs) and structure functions that behave appropriately at large scales, making it a better alternative to traditional fractal methods.
  • Utilizing a year-long global MODIS AOT dataset, the study reveals two distinct regimes of AOT variability: small-scale variations linked to local marine aerosols and larger-scale trends associated with aerosols from remote continental areas, enhancing the integration of remote sensing data with climate models.
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The aim of the study was to evaluate the influence of metal [Zn(II), Cu(II), Ni(II)] complexes with ursodeoxycholic acid (UDCA) on the viability and proliferation of tumour and non-tumour cells. Cell lines established from retrovirus-transformed chicken hepatoma (LSCC-SF-Mc29) and rat sarcoma (LSR-SF-SR) as well as from human cancers of the breast (MCF-7), uterine cervix (HeLa), lung (A549) and liver (HepG2) were used as model systems. Non-tumour human embryo (Lep-3) cells were also included in some of the experiments.

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An emerging alternative to the commonly used analytical methods for asbestos analysis is fluorescence microscopy (FM), which relies on highly specific asbestos-binding probes to distinguish asbestos from interfering non-asbestos fibers. However, all types of microscopic asbestos analysis require laborious examination of large number of fields of view and are prone to subjective errors and large variability between asbestos counts by different analysts and laboratories. A possible solution to these problems is automated counting of asbestos fibers by image analysis software, which would lower the cost and increase the reliability of asbestos testing.

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Nanofibrous poly(L-lactide-co-D,L-lactide) (coPLA) or coPLA/poly(ethylene glycol) implants loaded with plant polyphenolic compound gossypol (GOS) with anti-tumor activity were fabricated by electrospinning. Implants containing quaternized chitosan (QCh) were prepared by coating of the obtained fibrous materials with a thin film of cross-linked QCh. The morphology of the implants and chemical composition of the implant surface were studied by means of scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS).

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Fluorescence microscopy-based affinity assay could enable highly sensitive and selective detection of airborne asbestos, an inorganic environmental pollutant that can cause mesothelioma and lung cancer. We have selected an Escherichia coli histone-like nucleoid structuring protein, H-NS, as a promising candidate for an amphibole asbestos bioprobe. H-NS has high affinity to amphibole asbestos, but also binds to an increasingly common asbestos substitute, wollastonite.

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Remote sensing of aerosol optical properties is difficult, but multi-angle, multi-spectral, polarimetric instruments have the potential to retrieve sufficient information about aerosols that they can be used to improve global climate models. However, the complexity of these instruments means that it is difficult to intuitively understand the relationship between instrument design and retrieval success. We apply a Bayesian statistical technique that relates instrument characteristics to the information contained in an observation.

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Nanofibrous polylactide-based materials loaded with a natural polyphenolic compound gossypol (GOS) with antitumor properties were prepared by electrospinning. The nanofibrous materials were coated with a thin film of crosslinked quaternized chitosan (QCh). GOS incorporated in the nanofibrous mats was in the amorphous state.

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Fluorescence microscopy (FM) has recently been applied to the detection of airborne asbestos fibers that can cause asbestosis, mesothelioma and lung cancer. In our previous studies, we discovered that the E. coli protein DksA specifically binds to the most commonly used type of asbestos, chrysotile.

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Background: Recovery of post-stroke deficits can be achieved by modulating neuroplasticity with non-invasive brain stimulation. To evaluate potential effects of repetitive transorbital alternating current stimulation (rtACS) on stroke recovery we carried out a randomized, drug-controlled clinical trial.

Methods: Ninety-eight patients that had suffered ischemic stroke 21.

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Nanofibrous implants containing quaternized chitosan (QCh), poly(L-lactide-co-D,L-lactide) (coPLA), and the antitumor drug doxorubicin (DOX) were fabricated by electrospinning. The surface chemical composition and the morphology of the implants were characterized by XPS and SEM. In vitro cell viability studies demonstrated that QCh- and DOX-based implants exhibited high cytotoxicity against Graffi tumor cells.

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Nanofibrous materials containing the antitumor drug doxorubicin hydrochloride (DOX) were easily prepared using a one-step method by electrospinning of DOX/poly(L-lactide-co-D,L-lactide) (coPLA) and DOX/quaternized chitosan (QCh)/coPLA solutions. The pristine and DOX-containing mats were characterized by ATR-FTIR and X-ray photoelectron spectroscopy (XPS). The release rate of DOX from the prepared fibers increased with the increase in DOX content.

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Lungs of 40 ruminants from Bulgaria with natural small lungworm (Nematoda: Protostrongylidae) infections were investigated, including 16 goats, 15 sheep, 7 mouflons, and 2 chamois. Muellerius capillaris, M. tenuispiculatus, Cystocaulus ocreatus, Neostrongylus linearis, and Protostrongylus brevispiculum infections were predominantly associated with nodular lesions, and Protostrongylus rufescens, Protostrongylus hobmaieri and Protostrongylus rupicaprae were associated with extensive lesions located mainly along the length of the large bronchi.

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Fluorescence microscopy (FM) is one of the most important analytical tools in modern life sciences, sufficiently sensitive to allow observation of single molecules. Here we describe the first application of the FM technique for the detection of inorganic environmental pollutants-airborne asbestos fibers that can cause asbestosis, mesothelioma, and lung cancer. In order to assess FM capabilities for detecting and counting asbestos fibers, we screened E.

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