[Acute non-calculous cholecystitis in a young aged patient with COVID-19: A case report].

To date, it is known that COVID-19 can lead to damage to various organs and systems, despite the statistical prevalence of respiratory manifestations of the disease. In some cases, in order to treat complications of coronavirus infection, a multidisciplinary approach may be required, including on an urgent basis. The article presents a clinical case of acute non-calculous cholecystitis in a 41-year-old patient with COVID-19. The importance of timely diagnosis and providing the possibility of emergency surgical care to patients with COVID-19, even under the conditions of the anti-epidemic regime, has been demonstrated.

A new mouse unilateral model of diffuse alveolar damage of the lung.

OBJECTIVE AND DESIGN: The existing biological models of diffuse alveolar damage (DAD) in mice have many shortcomings. To offset these shortcomings, we have proposed a simple, nonsurgical, and reproducible method of unilateral total damage of the left lung in ICR mice. This model is based on the intrabronchial administration of a mixture of bacterial lipopolysaccharide (LPS) from the cell wall of S. enterica and α-galactosylceramide (inducing substances) to the left lung. METHODS: Using computer tomography of the lungs with endobronchial administration of contrast material, we have been able to perform an operative intravital verification of the targeted delivery of the inducer. The model presented is characterized by more serious and homogeneous damage of the affected lung compared to the existing models of focal pneumonia; at the same time, our model is characterized by longer animal survival since the right lung remains intact. RESULTS: The model is also characterized by diffuse alveolar damage of the left lung, animal survival of 100%, abrupt increases in plasma levels of TNFa, INFg, and IL-6, and significant myocardial overload in the right heart. It can be used to assess the efficacy of innovative drugs for the treatment of DAD and ARDS as the clinical manifestations that are developed in patients infected with SARS-CoV-2. Morphological patterns of lungs in the noninfectious ("sterile") model of DAD induced by LPS simultaneously with α-galactosylceramide (presented here) and in the infectious model of DAD induced by SARS-CoV-2 have been compared. CONCLUSION: The DAD model we have proposed can be widely used for studying the efficacy of candidate molecules for the treatment of infectious respiratory diseases, such as viral pneumonias of different etiology, including SARS-CoV-2.

Ultrasensitive detection enabled by nonlinear magnetization of nanomagnetic labels.

Geometrically confined magnetic particles due to their unique response to external magnetic fields find a variety of applications, including magnetic guidance, heat and drug delivery, magneto-mechanical actuation, and contrast enhancement. Highly sensitive detection and imaging techniques based on the nonlinear properties of nanomagnets were recently proposed as innovative strong-translational potential methods applicable in complex, often opaque, biological systems. Here we report on the significant enhancement of the detection capability using optical-lithography-defined, ferromagnetic iron-nickel alloy disk-shaped particles. We show that an irreversible transition between strongly non-collinear (vortex) and single domain states, driven by an alternating magnetic field, translates into a nonlinear magnetic response that enables ultrasensitive detection of these particles. The record sensitivity of ∼3.5 × 10-9 emu, which is equivalent to ∼39 pg of magnetic material is demonstrated at room temperature for arrays of patterned disks. We also show that unbound disks suspended in the aqueous buffer can be successfully detected and quantified in real-time when administered into a live animal allowing for tracing of their biodistribution. The use of nanoscale ferromagnetic particles with engineered nonlinear properties opens prospects for further enhancing the sensitivity, scalability, and tunability of noise-free magnetic tag detection in high-background environments for various applications spanning from biosensing and medical imaging to anti-counterfeiting technologies.

[Evaluation of condition and factors affecting activity effectiveness and visual performance of pilots who use night vision goggles during the helicopter flights].

According to analysis of questionnaire authors revealed factors, which affect activity effectiveness, and visual performance of pilots who use night vision goggles during the helicopter flights. These are: difficulty of flight tasks, flying conditions, illusion of attitude. Authors gave possible ways to reduce an impact of these factors.

Superheating in linear polymers studied by ultrafast nanocalorimetry.

To study phase transition kinetics on submillisecond time scale a sensitive ultrafast nanocalorimeter was constructed. Controlled ultrafast cooling, as well as heating, up to 10(6) K/s was attained. The method was applied for the measurements of the superheating phenomenon in a set of linear polymers: iPS, PBT, PET, and iPP. A power law relation between the superheating and the heating rate holds in the heating rate range 10(-2) - 10(4) K/s. A limiting superheating of about 10% of the melting temperature was observed at rates above 10(4) - 10(5) K/s. This limit depends on annealing conditions before sample melting. The observed superheating limit, as well as the power law, can be accounted for the internal stresses near the crystalline amorphous interface in semicrystalline polymers induced by heating, which are related to the thermal expansion gradients inherent in a semicrystalline material.

[Spectrum of microflora isolated from various areas of the female reproductive tract]. / Spektr mikroflory, izoliruemoi iz razlichnykh otdelov reproduktivnogo trakta zhenshchin.

The composition of microflora in different sections of the reproductive tract of women with disturbances of reproductive function was studied. The study revealed that the spectrum of microorganisms isolated from a bioptic specimen taken from the cavity of the small pelvis was narrower in comparison with such spectrum in material aspirated from the uterine cavity. The latter was narrower in comparison with that in the microflora of the lower sections of the reproductive tract. The possibility for one and the same patient to have both similarities and essential differences in the spectra of microflora in different sections of the reproductive tract was shown.