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Abstract Pulsed high-intensity focused ultrasound (pHIFU) has the capability to induce de novo cavitation bubbles, offering potential applications for enhancing drug delivery and modulating tissue microenvironments. However, imaging and monitoring these cavitation bubbles during the treatment presents a challenge due to their transient nature immediately following pHIFU pulses. A planewave bubble Doppler technique demonstrated its potential, yet this Doppler technique used conventional clutter filter that was originally designed for blood flow imaging. Our recent study introduced a new approach employing dynamic mode decomposition (DMD) to address this in an ex vivo setting. This study demonstrates the feasibility of the application of DMD for in vivo Doppler monitoring of the cavitation bubbles in porcine liver and identifies the candidate monitoring metrics for pHIFU treatment. We propose a fully automated bubble mode identification method using k-means clustering and an image contrast-based algorithm, leading to the generation of DMD-filtered bubble images and corresponding Doppler power maps after each HIFU pulse. These power Doppler maps are then correlated with the extent of tissue damage determined by histological analysis. The results indicate that DMD-enhanced power Doppler map can effectively visualize the bubble distribution with high contrast, and the Doppler power level correlates with the severity of tissue damage by cavitation. Further, the temporal characteristics of the bubble modes, specifically the decay rates derived from DMD, provide information of the bubble dissolution rate, which are correlated with tissue damage level—slower rates imply more severe tissue damage.

Introduction. Animal models for SARS-CoV-2 infection, reproducing the clinical features of COVID-19 in humans, are important tools for studying the pathogenesis of the disease, transmission of the pathogen and are indispensable for testing antiviral drugs and vaccines. The aim of the study was to assess the virulence and tissue tropism for golden Syrian hamsters of SARS-CoV-2 strains belonging to different epidemiologically significant variants: Wuhan-like, Delta, Omicron BA.1.1 and Omicron BA.5.2. Materials and methods. Hamsters were intranasally infected with different SARS-CoV-2 strains. Virulence and tissue tropism of SARS-CoV-2 strains were assessed by comparing the dynamics of weight, viral load in organs and histopathological changes in lungs in infected and uninfected animals. Results. The Wuhan-like Dubrovka strain had the greatest virulence for hamsters, which was manifested by the development of severe pneumonia and a delay in weight gain by 14.6%, high virus content in the lungs, nasal passages and brain — 6.2, 5,9 and 3.7 lg TCID50/ml of homogenate, respectively. Presumably, it was the infection of the Wuhan-like virus of the central nervous system that negatively affected the weight and general condition of the animals. When hamsters were infected with viruses belonging to the Delta and Omicron variants, the observed minor weight loss in animals was uninformative, so indicators such as lung histopathology, viral load in the lungs, nasal passages, heart and other organs played a decisive role in assessing the virus pathogenicity. A score assessment of lung histopathology was of particular value in assessing the severity of pneumonia, since it reduced subjectivity in evaluating the results of histological examination and provided a semi-quantitative assessment of the pathological process. Conclusion. Despite the revealed lower virulence for hamsters of viruses belonging to the Delta and Omicron variants compared to the ancestral Wuhan virus, this animal model for COVID-19 retains its value for conducting preclinical trials of antiviral drugs.

Introduction. Rotavirus infection causes more than 250 million episodes of acute gastroenteritis annually, of which approximately 130,000 cases in children under 5 years of age are fatal. In this regard, the search for drugs for the treatment of rotavirus infection seems extremely relevant.The aim of the research was to evaluate the antiviral activity of Cytovir®-3 against human rotavirus on a cellular infection model.Material and methods. The objects of the study were a mixture of active ingredients and individual components, identical in composition and ratio, contained in Cytovir®-3. The study was carried out using a monkey kidney cell culture MA-104 and a laboratory strain of human group A rotavirus — 568, genotype G3P. Cultural, virological, molecular biological and statistical methods were used during the study.Results and discussion. Analysis of the survival of MA-104 cells in the presence of Cytovir®-3 showed that in the concentration range from 100 to 200 µg/ml, the drug reproducibly exhibited antiviral activity, which was expressed in increased cell survival compared to the viral control. Cytovir®-3 in a non-toxic concentration of 150 µg/ml suppressed the reproduction of rotavirus by 1.0-2.0 lg СC₅₀/ml with various schemes of introduction into cell culture at all periods of observation, which was accompanied by a significant decrease in the concentration of viral RNA and a cytoprotective effect.

Introduction. Despite the end of the COVID-19 pandemic, the problem of vaccine prevention of this disease appears highly relevant. The emergence and widespread distribution of the Omicron SARS-CoV-2 variant of concern (VOC) and its sublineages has dramatically reduced the efficacy of vaccination. The possible approach to solving this problem is to develop a nasal live attenuated vaccine capable of activating humoral, mucosal, and cell-mediated immunity, providing a prolonged immune response and cross-protection against different VOCs. The aim of the study was to determine the immunization efficacy with attenuated cold-adapted Wuhan-like SARS-CoV-2 D-D2 strain against homologous and heterologous challenges. Materials and methods. The study was conducted on an animal model of coronavirus pneumonia in golden Syrian hamsters. The efficacy of immunization was assessed by comparing the dynamics of weight, viral load in organs and histopathological changes in the lungs in immunized and unimmunized animals. Results. Single intranasal immunization of golden Syrian hamsters with D-D2 strain showed its high immunogenicity: seroconversion was evident in all immunized animals. Wuhan-like D-D2 strain provides highly effective protection of hamsters against the development of productive infection and pneumonia when challenged both with ancestral virus and heterologous strains related to Delta (AY.122) and Omicron (sublineages BA.1.1 and BA.5.2) variants. Conclusion. SARS-CoV-2 attenuation is a promising strategy for the development of a highly effective nasal live COVID-19 vaccine.

We studied the relationships between functional alpha and beta diversities of fleas and their small mammalian hosts in 4 biogeographic realms (the Afrotropics, the Nearctic, the Neotropics and the Palearctic), considering 3 components of alpha diversity (functional richness, divergence and regularity). We asked whether (a) flea alpha and beta diversities are driven by host alpha and beta diversities; (b) the variation in the off-host environment affects variation in flea alpha and beta diversities; and (c) the pattern of the relationship between flea and host alpha or beta diversities differs between geographic realms. We analysed alpha diversity using modified phylogenetic generalized least squares and beta diversity using modified phylogenetic generalized dissimilarity modelling. In all realms, flea functional richness and regularity increased with an increase in host functional richness and regularity, respectively, whereas flea functional divergence correlated positively with host functional divergence in the Nearctic only. Environmental effects on the components of flea alpha diversity were found only in the Holarctic realms. Host functional beta diversity was invariantly the best predictor of flea functional beta diversity in all realms, whereas the effects of environmental variables on flea functional beta diversity were much weaker and differed between realms. We conclude that flea functional diversity is mostly driven by host functional diversity, whereas the environmental effects on flea functional diversity vary (a) geographically and (b) between components of functional alpha diversity.

In the modern world breastfeeding (BF) is considered as a significant factor in reducing the risk of developing malignant tumors of the mammary gland and ovaries. However, the problem of maintenance or refusing BF in malignant neoplasms (malignant neoplasms) still remains open. In recent years, there has been a steady increase in breast cancer (BC), especially in developed countries, with more than 10% of all breast malignancies (BC) diagnosed in women under 40 years of age. The presented article highlights aspects of maintaining lactation in different periods of the relevance of BF in relation to the timing of manifestation of cancer, and also presents data from the multicenter study POSITIVE (Pregnancy Outcome and Safety of Interrupting Therapy for women with endocrine responsIVE breast cancer) on the possibilities of implementing reproductive function and BF in women receiving therapy for hormone-receptor positive (HR+) BC stages I–III. BF with cancer detected in the postpartum period depends on the treatment of the underlying disease. In patients undergoing surgical treatment, BF is not contraindicated, but it is not always technically possible. During chemotherapy, BF is not recommended. When carrying out radiotherapy, it is possible to undergo BF using a healthy mammary gland. There is currently no evidence to suggest that BF woman diagnosed with cancer may have any negative effects. In general, it has been shown that preserving and maintaining lactation in women with a history of cancer is safe for both mother and child.

Aim. To evaluate the usage of antihypertensive drugs (AHDs) and their combinations in participants aged 35 to74 years with arterial hypertension (AH) in the population-based study ESSE-RF3.Material and methods. Representative samples of the population aged 35 to 74 years from 15 regions of Russia (n=28731) with a response rate over 70% were examined in the ESSE-RF3 study. Therapy received by 9944 participants with AH (with systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg, or when the subject was taking AHDs) was analyzed. Information about AHDs intake (brand name of the drug) was recorded by questionnaire and coded according to International Nonproprietary Names by classes. Statistical analysis was performed using the open-source R 4.1 environment. Comparison of discrete indicators between groups was performed using Fisher’s exact test. The significance level for all tested hypotheses was taken as.05. The study was approved by the Ethics Committee of FGBI “NMRC TPM” of the Ministry of Health of the Russian Federation, each participant signed an informed consent.Results. Among the patients receiving therapy for AH, angiotensin-converting enzyme inhibitors (ACEIs) were used by 38.8% of participants, angiotensin receptor blockers (ARBs) — 31.6%, betablockers (BBs) — 29.0%, сalcium channel blockers (CCBs) — 21.5%, diuretics — 18.6%, 1.1% — outdated AHDs; 8.6% — other groups of drugs. Monotherapy was used by 53.1% of patients, 33.1% of participants received two, and 13.9% received three AHDs. Among participants taking two or more AHDs (including single-pill combinations (SPC)), males most often received the combination of BB+ ACEI and females — BB+ARBs. SPC AHDs were used by 10.3% of those receiving therapy (males: 9.8%, females: 10.6%). Among SPCs, the top three combinations were CCBs + ACEIs (28%), diuretics + ACEIs (27.5%), and diuretics + ARBs (24.4%).Conclusion. The population study ESSE-RF3, based on the survey of a representative sample of the Russian population aged 35-74 years, showed that more than a half of participants with AH receiving therapy were used the monotherapy, only every tenth of those treated received SPC. The problem of insufficient patients’ literacy was indicated — about 1% of patients received outdated AGPs. In addition, 8.6% of patients used non-AHDs for the treatment of AH. For improving the control of AH treatment, it is necessary to increase the adherence of patients to the prescribed therapy and more strict adherence of doctors to the published guidelines for AH treatment.

This review provides an overview of the challenges of identifying dual sensory impairment in children with congenital disabilities. The concept of deafblindness and the special needs of the group with hearing and visual impairments are reviewed. The difficulties of defining this condition due to the heterogeneity of this group are emphasized. The evolution of the etiology of sensory impairment, typical for recent decades, is described, due to the progress of medical science, which makes it possible to keep alive children with severe genetic pathologies and those born considerably prematurely. The characteristics of cerebral hearing and visual impairments, still insufficiently studied but coming to the forefront in terms of prevalence among children in developed countries, as well as the features of their identification are presented. The difficulties in the organization of psychological and pedagogical assessments of children with congenital dual sensory impairment and the interpretation of their results are considered. The conclusion about the importance of the functional approach in the assessment of sensory functions in children with congenital complex disabilities is formulated.

Digestive enzymes can selectively degrade proteins, carbohydrates and lipids; and their supplementation alongside food may accelerate the breakdown of complex food matrices, facilitate greater nutrient absorption, decrease food sensitivities and aid in the management of certain disease states. Several intrinsic and extrinsic factors govern food digestion and for every individual this phenomenon is unique. This study was conducted as a randomized, crossover, placebo-controlled design where each participant served as their own control. This post-hoc analysis investigated the impact of a dietary enzyme supplementation blend known as Elevase® on dietary macromolecule digestion in samples from otherwise healthy participants that had previously undergone a small bowel resection, resulting in an ileostomy (NCT04489810). This is the first time this study-paradigm has been used for the assessment of in vivo dietary breakdown following enzyme supplementation. Arguably, this technique offers superior data when compared to that generated in artificial gut digestion models, preclinical animal models, or indeed conventional clinical studies using stool analyses, as it allows real-time access to samples in situ in the small intestine where the majority of nutritional absorption takes place. It was demonstrated that after 4 h, Elevase® significantly increased monosaccharide levels (predominantly glucose and fructose) in the ileostomy samples taken from the same individuals on the same diet on a different day. In addition, the bile salt taurohyodeoxycholic acid was also increased, suggesting a physiological host response to the macromolecule digestion induced by the enzymatic blend. Overall, these findings suggest Elevase® could accelerate food digestion and potentially increase nutrient availability from the diet.

Introduction: Cerebral arterial air embolism (CAE) is a serious and potentially dangerous condition that can interrupt the blood supply to the brain and cause stroke. One of the promising gas mixtures for emergency treatment of air embolism is an oxygen-helium mixture.Methods: We modeled CAE in awake rats by injecting air into the common carotid artery. Immediately after CAE, animals were either untreated or underwent hyperbaria, oxygen inhalation, heated air inhalation, or helium-oxygen mixture inhalation. Body temperature, locomotor activity, respiratory and cardiovascular parameters were monitored in the animals before CAE modeling, and 3 and 24 h after CAE modeling.Results: After 3 hours of CAE modeling in awake rats, depression of the nervous, cardiovascular and respiratory systems, as well as decreased body temperature were observed. 24 h after CAE modeling multifocal cerebral ischemia was observed. Normobaric helium-oxygen mixture inhalation, on par with hyperbaric treatment, restored body temperature, locomotor activity, respiratory volume, respiratory rate, and blood pressure 3 hours after CAE, and prevented the formation of ischemic brain damage lesions 24 h after CAE.Discussion: Thus, inhalation of a heated oxygen-helium gas mixture (O2 30% and He 70%) immediately after CAE improves the physiological condition of the animals and prevents the foci of ischemic brain damage formation.

The main fluorine-concentrating minerals in rocks are mainly apatites, amphiboles, micas, fluorites, sphenes, villiomites, in which fluorine is found in compounds with Ca, Mg, Na. The yield of the Xâray fluorescence of fluorine depends on the element with which it is chemically bound. Taking into account this factor, three versions of calibration dependences for fluorine in the composition of CaF.sub.2, MgF.sub.2, and NaF were obtained using pressed tablets. Mixtures of these fluorides with granite, basalt, and limestone were used for calibration. To select an adequate calibration for the determination of fluorine in a batch of unknown samples, it was proposed to use the results of a selective analysis of fused samples of the batch., Author(s): T. G. Kuz'mina [sup.1] , T. V. Romashova [sup.1] , M. A. Troneva [sup.1] , I. V. Khokhlova [sup.1] Author Affiliations: (1) grid.439081.7, 0000 0004 0380 8849, Vernadsky Institute [...]