[Dynamics the parameters of mineral metabolism in hospitalized patients with COVID-19, the impact of etiotropic and pathogenetic therapy].

The high prevalence of COVID-19 requires the research progress on the disease pathogenesis. There is a lot of data confirming the association between mineral metabolism and the severity of COVID-19. AIM: To study the dynamics of mineral metabolism parameters in patients with a confirmed COVID-19 at the time of hospitalization and after discharge, including the impact of etiotropic and pathogenetic therapy on them. MATERIALS AND METHODS: A single-center study of 106 patients (aged ≥18 years) with clinically or laboratory confirmed diagnosis of COVID-19 was carried out at the Endocrinology Research Centre, Moscow. Baseline biochemical parameters, including serum calcium, phosphorus, albumin, 25(OH)D, parathyroid hormone (PTH), inflammatory markers, and instrumental assessment of COVID-19 severity were performed before specific immunotherapy, as well as on 3rd and 7th days of hospitalization and before discharge. Statistical analysis was performed with Statistica 13 software (StatSoft, USA). RESULTS: On the first day, hypocalcemia (low albumin-adjusted calcium level) was detected in 40.6% of cases, the prevalence of vitamin D deficiency/insufficiency amounted to 95.3% of cases. At the same time, secondary hyperparathyroidism was identified only in 14.2% of patients. A comparative analysis of mineral metabolism during hospitalization (between 1, 3, 7 days of hospitalization and before discharge) during baricitinib treatment revealed a statistically significant increase in albumin-adjusted calcium by the end of hospitalization (p<0.001, Friedman criterion, Bonferroni correction p0=0.01). A pairwise comparison of subgroups, depending on the therapy, revealed a statistically significantly lower level of albumin-adjusted calcium on 3rd day among patients on baricitinib monotherapy or combined with tocilizumab compared with a subgroup of patients undergoing etiotropic treatment (2.16 [2.13; 2.18] mmol/l vs 2.23 [2.19; 2.28] mmol/l, p=0.002, U-test, Bonferroni correction p0=0.012). CONCLUSION: Patients with severe coronavirus infection are characterized by a high prevalence of vitamin D deficiency and hypocalcemia. Associations between calcium and saturation as well as the severity of lung lesion characterizes hypocalcemia as an important predictor of severe course and poor outcome in COVID-19. Pathogenetic therapy with baricitinib, including in combination with tocilizumab, contributes to achieve normocalcemia, but further studies are required.

Tomographic and centroid reconstructions of plasma emission on C-2W via enhanced 300-channel bolometry system.

The C-2W experimental device at TAE Technologies utilizes neutral beam injection and edge biasing to sustain long-lived, stable field reversed configuration (FRC) plasma. An ongoing effort is under way to optimize the electrode biasing system, which provides boundary control to stabilize the FRC. To this end, tomography offers a powerful and non-invasive technique as tomographic reconstruction of the FRC emission profile provides an important assessment of global stability. Recently, a new signal acquisition system was implemented on a bolometer array dedicated to tomography on C-2W, significantly enhancing the signal-to-noise of the collected data. The array consists of 300 simultaneously digitized photodiode channels that respond to a broad range of wavelengths, from soft x-ray to near-infrared, as well as energetic particles, yielding 180 unique lines of sight that intersect a toroidal plane of the FRC near the mid-plane. Utilizing the collected photo-signals from a set of plasma discharges in which the electrode biasing was intentionally terminated mid-shot, time-resolved reconstruction of the plasma emissivity is achieved via pixel-based 1D and 2D tomographic algorithms, revealing sharply annular profiles with a clear magnetohydrodynamic (MHD) mode structure. In addition, reconstruction of the plasma center-of-emission trajectories via a centroid algorithm applied to the same set of discharges demonstrates a cyclical plasma wobble. Crucially, both the tomography reconstruction and centroid reconstruction indicate an n = 1 toroidal mode that reverses from the electron diamagnetic direction to the ion diamagnetic direction and grows in amplitude after bias termination, qualitatively consistent with the expected stabilizing effect of electrodes.

Assessment of the systemic immune response in patients with inflammatory complications of large joint implants.

One of the most common reasons for the progressing of aseptic instability of implanted structures in patients with end-stage osteoarthrosis is a disorder of immunogenulatory processes of bone tissue remodeling along with chronic inflammatory response influenced by endoprosthesis wear components. This research features the specifics of systemic immune response in patients with inflammatory complications in late postoperative period after total replacements of large joints. The factor analysis enabled determining the most significant immunological mechanisms associated with the progressing of implant aseptic instability. Pathogenetically significant components involved in the formation of cellular and humoral immune responses in patients with signs of inflammatory activity in late postoperative period have been identified. Our findings can be used in designing diagnostic and prognostic criteria for systemic inflammatory response severity in preoperative monitoring of the condition of patients in need of large joint arthroplasties, and also in detecting the progress of implant aseptic instability.

Cell Immunity in Implant-Associated Infections Caused by Biofilm-Forming Microorganisms.

High biofilm-forming capacity of Staphylococcus spp. strains isolated from biomaterial of patients with infectious complications after primary knee replacement developed within 6-12 months after surgery was experimentally demonstrated. Differential leukocyte counts and some indicators of cell immunity in these patients were compared with those in patients without purulent complications and healthy volunteers. In patients with implant-associated infection, the relative numbers of T cells (both T-helpers and T-suppressors) B cells were significantly (p<0.05) reduced, while the number of NK cells was significantly increased in comparison with the corresponding parameters in other groups. The revealed changes attest to cell immunity failure in biofilm infection.

Biofilm Formation by Gram-Negative Bacteria during Implant-Associated Infection.

Nonfermenting gram-negative bacteria and enterobacteria isolated from various biomaterials of patients of the orthopedic trauma hospital with implant-associated infection demonstrated significantly (p<0.05) higher biofilm formation capacity than the reference strains. The differences in biofilm formation kinetics were revealed: biofilm maturation and the beginning of its dispersion after 48-h incubation in enterobacteria and longer biofilm maturation phase in nonfermenting gram-negative bacteria. It was found that the strains isolated from sonication fluid have reliably (p<0.05) higher propensity to biofilm formation than bacteria isolated from aspirate and wound exudate.

Spatially resolved Thomson scattering measurements of the transition from the collective to the non-collective regime in a laser-produced plasma.

We present optical Thomson scattering results that image for the first time in a single measurement the spatial transition from collective to non-collective scattering. Data were taken in the Phoenix laser laboratory at the University of California, Los Angeles. The Raptor laser was used to ablate a carbon plasma, which was diagnosed with the frequency-doubled Phoenix laser serving as a Thomson scattering probe. Scattered light was collected from the laser plasma up to 10 cm from the target surface and up to 10 us after ablation, and imaged with high spatial and spectral resolutions. The results show a strong Thomson collective feature close to the target surface that smoothly transitions to a non-collective feature over several mm.

Enhanced collisionless shock formation in a magnetized plasma containing a density gradient.

Two-dimensional hybrid simulations of super-Alfvénic expanding debris plasma interacting with an inhomogeneous ambient plasma are presented. The simulations demonstrate improved collisionless coupling of energy to the ambient ions when encountering a density gradient. Simulations of an expanding cylinder running into a step function gradient are performed and compared to a simple analytical theory. Magnetic flux probe data from a laboratory shock experiment are compared to a simulation with a more realistic debris expansion and ambient ion density. The simulation confirms that a shock is formed and propagates within the high density region of ambient plasma.

Magnetic field measurements in low density plasmas using paramagnetic Faraday rotator glass.

Paramagnetic Faraday rotator glass (rare-earth doped borosilicate) with a high Verdet constant will be used to measure the magnetic field inside of low density Helium plasmas (T(e) ~ 5 eV, T(i) ~ 1 eV) with a density of n ~ 10(12) cm(-3). Linearly polarized light is sent through the glass such that the plane of polarization is rotated by an angle that depends on the strength of the magnetic field in the direction of propagation and the length of the crystal (6 mm). The light is then passed into an analyzer and photo-detector setup to determine the change in polarization angle. This setup can detect magnetic fields up to 5 kG with a resolution of <5 G and a temporal resolution on the order of a nanosecond. The diagnostic will be used to characterize the structure and evolution of laser-driven collisionless shocks in large magnetized plasmas.

Feasibility of characterizing laser-ablated carbon plasmas via planar laser induced fluorescence.

Planar laser induced fluorescence (PLIF) imaging can potentially assess ion distributions and coupling in the context of super-Alfvénic ablation plasma expansions into magnetized background plasmas. In this feasibility study, we consider the application of PLIF to rapidly expanding carbon plasmas generated via energetic laser ablation of graphite. By utilizing hydrodynamic and collisional-radiative simulations, we identify schemes accessible to commercially available tunable lasers for the C I atom, the C II ion, and the C V ion. We then estimate the signal-to-noise ratios yielded by the schemes under reasonable experimental configurations.

Alloys of platinum and early transition metals as oxygen reduction electrocatalysts.

The widespread use of low-temperature polymer electrolyte membrane fuel cells for mobile applications will require significant reductions in the amount of expensive Pt contained within their cathodes, which drive the oxygen reduction reaction (ORR). Although progress has been made in this respect, further reductions through the development of more active and stable electrocatalysts are still necessary. Here we describe a new set of ORR electrocatalysts consisting of Pd or Pt alloyed with early transition metals such as Sc or Y. They were identified using density functional theory calculations as being the most stable Pt- and Pd-based binary alloys with ORR activity likely to be better than Pt. Electrochemical measurements show that the activity of polycrystalline Pt(3)Sc and Pt(3)Y electrodes is enhanced relative to pure Pt by a factor of 1.5-1.8 and 6-10, respectively, in the range 0.9-0.87 V.

[Antifungal activity of the components of the drug cerbiden of plant origin]. / Antyfunhal'na aktyvnist' komponentiv preparatu tserbidenu roslynnoho pokhodzhennia.

Complex drug cerbiden has been studied in vitro for the antifungal activity of its components. It has been established that the spectrum of antifungal effect and activity of cerbiden, with respect to fungi conditionally pathogenic for people, is determined by antibiotic compounds--aromatic carbohydrate phenylheptatryin and sesquiterpene phenol cernusol. They process a spectrum of antifungal activity analogous to cerbiden and activity close to Candida spp., some basidial yeast, dermatophytes, a number of Mucorales.

[Study of the cerbiden spectrum of antifungal activity against fungi pathogenic to humans]. / Vyvchennia spektra antyfunhal'noï diï tserbidenu na umovno patohenni dlia liudyny gryby.

A comparatively wide spectrum of cerbiden antifungal activity against the fungi pathogenic for human has been determined. Cerbiden is active against clinical and museum strains of Candida spp. and other yeasts; Trichophyton spp., Microsporum spp. of Dermatophytaceae family, museum strains of some species from Mucor, Rhizopus, Rhizomucor genera of Mucoraceae family; and it is not active with respect to studied fungi of Aspergillus and Penicillium genera of Moniliaceae family.

[Investigation of the activity of the preparation cerbiden against Candida spp]. / Doslidzhennia aktyvnosti preparatu tserbidenu shchodo Candida spp.

Antifungal activity of a new complex antibiotical preparation cerbiden obtained from medical plant Bidens cernua L. of the Asteraceae family, was investigated in vitro against the clinical and museum strains of Candida spp. High cerbiden activity against clinical and museum strains of Candida albicans, C. tropicalis, C. krusei, C. parapsilosis, C. guilliermondii, sensitive and resistant to nystatin, amphotericin B and clotrimazole was determined.

[The effect of solar ultraviolet on the system of microorganisms-higher plant antibiotics, a natural phenomenon and a new approach to enhancing the efficacy of antibiotics]. / Vozdeistvie ul'trafioleta solnechnogo izlucheniia na sistemu mikroorganizmy--antibiotiki vysshikh rastenii--prirodnoe iavlenie i novyi podkhod k povysheniiu éffektivnosti antibiotikov.

Under the effect of solar radiation some antibiotics of plant origin (phenylheptatriin, bakuchiol and others) showed antimicrobial phototoxicity differing by the spectrum and activity from the antibiotic action. The highest in vitro antimicrobial phototoxicity was observed with polyacetylene phenylheptatriin: the activation effect of solar radiation on it was due to UV-A and developed in gaseous phase or to a lesser extent in dispersed liquid phase. For comparison, 18 currently used antibiotics of various chemical structure were investigated and no phototoxicity under the effect of solar radiation with respect to the tested microbes was detected. In nature the phenomenon of antimicrobial phototoxicity of plant secondary metabolites due to the effect of solar radiation is probably of large scale. The study of the phenomenon is a new trend in biology (plant antibiotics and phytoncides, phytoimmunity, ecological and evolutionary microbiology, etc.) and a new approach to increase the efficacy of some antibiotics and to develop principally novel photochemotherapeutics for the treatment of infections in humans, animals and plants.

[A complex antibiotic preparation obtained from a medicinal plant from the family Asteraceae]. / Kompleksnyi antibioticheskii preparat, poluchennyi iz lekarstvennogo rasteniia semeistva Asteraceae.

Data of in vitro and in vivo investigations of antimicrobial activity of preparation K carried out both by the authors and by other researchers and pharmacological properties of this preparation have been summarized. Preparation K has been obtained from medicinal plant of the Asteraceae family. It is a natural composition of two antibiotics and of a number of minor compounds. The preparation possesses a wide spectrum of biological action. It is antimicrobially active against gram-positive bacteria, some species of gram-negative bacteria, fungi-dermatophytes including antibiotic-resistant strains. It is not toxic for animals, stimulates some defensive reactions of macroorganism, has immunomodulating, anti-inflammatory, anti-exudative, keratolytic properties. Preparation K is efficient for treatment of experimental mycoses of animals and is clinically tested as a local agent for treatment of dermatomycoses.