Study of transhydrogenase systems features in the mutants of the yeast pachysolen tannophilus for the production of ethanol and xylitol from agricultural wastes

The key catabolic enzymes of D-xylose, an important structural component of different agricultural wastes, were studied in cells of mutant strains of the xylose-assimilating yeast Pachysolen tannophilus. The evaluation of catalytic activity and cofactor specificity of xylose reductase (ЕС 1.1.1.307) and xylitol dehydrogenase (ЕС 1.1.1.9) confirmed the dependence of intracellular catabolic pathway for D-xy lose on the NAD×H/NADP×H ratio, formed under microaerobic conditions. The study of total activity of some NAD+ /NAP×H-dependent dehydrogenases revealed the metabolic characteristics of the yeast cells, which could ensure selective ethanol or xylitol production. Thus, the efficient involvement of D-xylose into the Embden–Meyerhof–Parnas pathway provided not only the high activities of xylose reductase and xylitol dehydrogenase, but also of 1-glycerophosphate dehydrogenase (EC 1.1.1.8) and lactate dehydrogenase (ЕС 1.1.1.27), respectively. The inhibition of activity of these enzymes led to selective production of xylitol from D-xylose. On the base of the experimental results, the principles of metabolic engineering of xylose-assimilating yeasts were formulated. The possibility of bioethanol and xylitol production from different agricultural wastes using xyloseassimilating yeasts are discussed

Use of lipids of Chlorella microalgae in poultry meat marinades and sauces recipes

ArticleThe aim of this study is to develop formulations and technologies for fermented poultry meat products with the addition of whey and lipid extracts obtained from Chlorella microalgae. Lyophilized microalgal biomass was obtained from cell suspensions of Chlorella sorokiniana (strain 211-8k) cultivated in a closed photobioreactor under laboratory conditions. For the cell wall disintegration, the biomass samples were homogenized using a high-speed homogenizer at 10,000 vol min-1 for 5 minutes. The lipid extraction was performed on a Sohxlet apparatus Buchi E-812 SOX with the solvent extraction system ethanol: n-hexane (1: 9). The higher fatty acids composition of the obtained microalgal lipid extracts was determined by gas chromatography with flame-ionization detection using nitrogen as a carrier gas. The ω-3 and ω-6 content represented 26.59% and 19.05% respectively, which indicates that these lipid extracts have high nutritional values. The curd whey was obtained from cow's milk of summer and winter production from 2017 to 2018 (Lomonosov district auxiliary farm, Leningrad region); and lyophilized Direct Vat Set (DVS) cultures (Ch. Hansen, Denmark). The organic acids and carbohydrate content in the serum was determined by ion-exclusion HPLC. The FD-DVS CHN-19 culture was selected to produce a serum with improved organoleptic characteristics and a lower propionic acid content (0.01 g L -1 ). To obtain an optimal ω-3 / ω-6 ratio, a phyto-additive mixture based on sunflower oil and lipid extracts from C. sorokiniana microalgae at a ratio of 5–10: 1 is proposed to be used in recipes and technologies of sauces and marinades. It is established that the use of curd whey marinades allow to increase the water-holding capacity (WHC) by 6−8% and to reduce losses during heat treatment of poultry meat from 2 to 11%

A method for obtaining plastid pigments from the biomass of Chlorella microalgae

Microalgae are distinguished from land plants by the high content of plastid pigments and the biodiversity of carotenoids. The aim of this study is to develop a technology for extracting a pigment complex from the biomass of the microalgae of the genus Chlorella and to determine the extracted pigments’ composition. To obtain biomass, a crude cell suspension of microalgae was used, which was obtained under laboratory conditions for pre-culture cultivation of C. sorokiniana (strain 211-8k). The extraction of plastid pigments from air-dry biomass after disintegration of cell membrane was performed in the 40 kHz mode. It was found that the highest pigment content in ethanol extracts was observed after 30 min (870.0 ± 27.1 mg L -1 ) at 45−50 °C. The pigments’ composition in the resulting total extracts was determined by spectrophotometry and the Reverse Phase HPLC method. The established content of chlorophyll a in the obtained extracts was 537.5 ± 10.0 mg L -1 , the content of chlorophyll b was 182.5 ± 27.5 mg L -1 ; the maximum output of the amount of carotenoids in extracts was 150.0 ± 10.0 mg L -1 . Thus, the main identified forms of carotenoids in extracts from the biomass of microalgae C. sorokiniana were xanthophylls: lutein and fucoxanthin (18.6 and 4.7% of the amount of pigment in extract, respectively) and β-carotene (1.8% of the amount of pigment). It is planned to further fractionate the obtained total extracts of the pigment complex to obtain various forms of chlorophylls and carotenoids to study the spectrum of physiological activity of plastid pigments

Antirheumatic drugs and COVID-19: frustrations and hopes

In accordance with current views on the pathogenesis of the new coronavirus infection, some antirheumatic drugs are considered as therapeutic agents for suppressing the hyperinflammatory response in severe COVID-19. The review presents literature data on the efficacy and safety of certain basic anti-inflammatory and genetically engineered drugs in patients with COVID-19. Hydroxychloroquine is not indicated for the treatment of SARS-CoV-2 infection of any severity due to the lack of therapeutic benefits, the likelihood of a worse prognosis in more severe patients and the development of adverse reactions, especially when used concomitantly with azithromycin. The use of systemic glucocorticoids (GC) in patients with COVID-19 who require oxygen support leads to a decrease in mortality and an improvement in the prognosis of the disease. However, the optimal time of administration, dose and duration of HA administration remain the subject of further research. Despite the encouraging data, it is too early to draw final conclusions about the feasibility of using tocilizumab in COVID-19, since no randomized clinical trials have demonstrated a clear advantage of the drug in terms of reducing mortality. The use of anakinra does not reduce the need for noninvasive / invasive lung ventilation or the mortality of patients with COVID-19. Two drugs from the group of tumor necrosis factor inhibitors - infliximab and adalimumabare currently being considered as possible treatment options for COVID-19. The use of a combination of baricitinib and remdesivir for the treatment of COVID-19 patients requiring oxygen support has been approved. New RCTs are needed to study the effectiveness of other anti-rheumatic drugs in COVID-19

Post covid syndrome and rheumatic diseases: focus on rheumatoid arthritis (own data)

Introduction. In modern reality postcovid syndrome (PCS) is characterized by clinical heterogeneity and multi-organ involvement, often presenting a differential diagnostic and therapeutic problem. However, in most studies of PCS, stratification of patients taking into account individual comorbid conditions was not performed. Thus, only an extremely small number of studies have been devoted to assessing the course of PCS in rheumatic diseasesPurpose. To characterize the features of the course of COVID-19 in patients with rheumatoid arthritis, as well as to conduct a comparative assessment of clinical and demographic parameters in groups of patients with rheumatoid arthritis, differentiated by the presence of PCS.Materials and methods. The material of the questionnaire which contained questions regarding socio-demographic data of respondents, information on rheumatological history, comorbid diseases, data on past COVID-19, including cases of re-infection, and PCS.Results.The study included 32 adult patients (29 women, 90%) with a reliable diagnosis of rheumatoid arthritis. Of the 32 patients who underwent COVID-19, in 23 cases it was possible to form a judgment about the presence or absence of PCS. To study PCS, 23 patients were stratified into two groups: 11 (47.8%) patients developed PCS (Group 1) and 12 patients had COVID-19 without consequences (Group 2). Both groups were represented predominantly by women (90.9% and 91.7%, respectively). In the general group 37.5% of patients with COVID-19 required inpatient treatment. The number of symptoms associated with COVID-19 did not correlate with RA activity, however, patients with higher RA activity were more likely to report increased arthralgia as a symptom of COVID-19. 47.8% of COVID-19 survivors experienced PCS. The average age, the number of comorbid diseases and the severity of RA symptoms at the time of COVID-19 were relatively higher in the group of patients with RA and PKS. Patients with PKS also noted a higher frequency of hospitalizations and a more severe course of COVID-19.Conclusions. A quantitative assessment of the risk of developing PKS is needed, which will serve as a basis for developing a strategy aimed at prevention, timely diagnosis and treatment of this syndrome in patients with RS. To this end, further studies on larger cohorts of patients are required

Multimode Quantitative Scanning Microwave Microscopy of In Situ Grown Epitaxial Ba\u3csub\u3e1-x\u3c/sub\u3eSr\u3csub\u3ex\u3c/sub\u3eTiO\u3csub\u3e3\u3c/sub\u3e Composition Spreads

We have performed variable-temperature multimode quantitative microwavemicroscopy of in situepitaxial Ba1−xSrxTiO3 thin-film composition spreads fabricated on (100) LaA1O3 substrates. Dielectric properties were mapped as a function of continuously varying composition from BaTiO3 to SrTiO3. We have demonstrated nondestructive temperature-dependent dielectric characterization of local thin-film regions. Measurements are simultaneously taken at multiple resonant frequencies of the microscope cavity. The multimode measurements allow frequency dispersion studies. We observe strong composition-dependent dielectric relaxation in Ba1−xSrxTiO3 at microwave frequencies

Полиартрит, ассоциированный с COVID-19 (клинический случай)

The article describes the clinical observation of the onset of polyarthritis after COVID-19. Clinical data, laboratory tests' and instrumental methods results in dynamics, as well as approaches to therapy are presented. The discussion reflects modern views on the causes of the development of articular syndrome after SARS-CoV-2, with special attention to the need for a careful study of the history, clinical and laboratory data of patients with COVID-19.В статье приводится описание клинического наблюдения дебюта полиартрита после перенесенного COVID-19. Представлены клинические данные и результаты лабораторных и инструментальных методов обследования в динамике, а также подходы к терапии. В обсуждении отражены современные взгляды на причины развития суставного синдрома после SARS-CoV-2, указано на необходимость внимательного изучения анамнеза, клинических и лабораторных данных пациентов с COVID-19

Хронический гепатит В у пациентов ревматологического стационара: проблемы скрининга и реактивации инфекции

   Objective: to evaluate the completeness of screening for hepatitis B virus (HBV) infection in HBsAg-positive patients admitted to a rheumatology hospital and to follow the history of HBV reactivation/seroversion during antirheumatic therapy.   Material and methods. The results of initial and repeated (if applicable) hospitalizations were analyzed in 80 patients with rheumatic diseases (RD), including 55 (69%) women and 25 (31 %) men, with Australian surface antigen (HBsAg), admitted to the V.A. Nasonova Institute of Rheumatology from January 1, 2020 to July 20, 2022 (30 months).   Results and discussion. The total number of hospitalizations to the clinic during the observation period, including repeat admissions, was 13,681. The number of hospitalizations in 80 patients with HBV infection during the observation period, including repeat admissions, was 144, of which for systemic vasculitis – 6 (8 %), other systemic connective tissue diseases – 16 (20 %), osteoarthritis and post-traumatic changes of joints – 14 (15 %), inflammatory joint diseases – 42 (54 %). Cases of HBV reactivation/seroverion, both in anamnesis and during observation, were detected in 9 (11 %) patients, and most frequently (n = 5) they were registered during methotrexate therapy.   Conclusion. HBV infection in patients with RD leads to significant difficulties in the selection of drug therapy, due to the risk of reactivation of the infection. The results obtained indicate incomplete screening of patients with RD for HBV infection during the preclinical phase. Further investigation is needed to develop clear recommendations for the management of patients with RD infected with HBV.   Цель исследования – оценить полноту выполнения скрининга на наличие инфекции, вызванной вирусом гепатита В (HBV), у больных, позитивных по HBsAg, поступающих в стационар ревматологического профиля, и проследить историю реактивации/серореверсии HBV на фоне антиревматической терапии.   Материал и методы. Проанализированы результаты первичной и повторной (при наличии) госпитализации у 80 больных с ревматическими заболеваниями (РЗ), среди которых было 55 (69 %) женщин и 25 (31 %) мужчин, имеющих поверхностный «австралийский» антиген (HBsAg), госпитализированных в ФГБНУ «Научно-исследовательский институт ревматологии им. В. А. Насоновой» с 1. 01. 2020 по 20. 07. 2022 г. (30 мес).   Результаты и обсуждение. Общее число госпитализаций в клинику за время наблюдения, включая повторные, составило 13 681. Число госпитализаций у 80 больных с HBV-инфекцией за период наблюдения, включая повторные, составило 144, из них по поводу системных васкулитов – 6 (8 %), других системных заболеваний соединительной ткани – 16 (20 %), остеоартрита и посттравматических изменений суставов – 14 (15 %), воспалительных заболеваний суставов – 42 (54 %). Случаи реактивации/серореверсии HBV как в анамнезе, так и в процессе наблюдения выявлены у 9 (11 %) больных, причем наиболее часто (n = 5) они регистрировались на фоне терапии метотрексатом.   Заключение. Инфицированность HBV больных с РЗ создает значительные трудности при подборе лекарственной терапии, поскольку существует опасность реактивации инфекции. Полученные результаты свидетельствуют о неполном обследовании пациентов с РЗ на HBV-инфекцию на догоспитальном этапе. Необходимы дальнейшие исследования для выработки четких рекомендаций по ведению больных с РЗ, инфицированных HBV

К вопросу о безопасности применения глюкокортикоидов в терапии ревматоидного артрита

Glucocorticoids (GCs) are one of the most commonly used drugs for the treatment of rheumatoid arthritis (RA), the effectiveness of which is beyond doubt. The review considers current literature data on the safety of GCs use, as well as the most common adverse events associated with such therapy. Most authors point to an increased risk of complications with an increase in the daily dose and/or duration of GCs treatment. At the same time, a safe dose of GCs has not been determined. Probably, the optimal tactic is the selection of an individual dose of GCs in each individual case, taking into account the activity of RA and the spectrum of comorbid conditions. In this case, the minimum effective doses and short courses of GCs should be used, regular monitoring of clinical and laboratory parameters should be carried out in order to detect adverse events early.Глюкокортикоиды (ГК) – одно из наиболее часто применяемых средств для лечения ревматоидного артрита (РА), эффективность которого не подлежит сомнению. В обзоре рассмотрены современные данные литературы о безопасности применения ГК, а также наиболее частые неблагоприятные явления, связанные с такой терапией. Большинство авторов указывают на повышение риска развития осложнений при увеличении суточной дозы и/или продолжительности лечения ГК. В то же время безопасная доза ГК не определена. Вероятно, оптимальной тактикой является подбор индивидуальной дозы ГК в каждом отдельном случае с учетом активности РА и спектра коморбидных состояний. При этом следует использовать минимальные эффективные дозы и короткие курсы ГК, проводить регулярный мониторинг клинических и лабораторных показателей с целью раннего выявления неблагоприятных явлений