Low molecular weight thymic factor inhibits histamine release from basophils

Low molecular weight thymic factor stimulates the suppressor function of T-lymphocytes, increases cAMP content (but not cGMP) in lymphocytes and inhibits histamine release from sensitized basophils. The mechanisms of LTF action are discussed

Clinical observation pseudoobstruction syndrome of the stomach's output part and small intestine of a patient with systematic lupus erythematosis

Stomach's output part and small intestine, combining with damaging of the urinary tract is a rare systemic lupus eritematosus (SLE) manifestation. The patient is 32 years old, suffering from SLE with damaged join, blood system, secondary antiphospholipid syndrome with pulmonary embolism in the history and formation of high postembolic pulmonary hypertension on therapy with hydroxychloroquine and low doses of corticosteroids, was hospitalized because of persistent nausea, vomiting, loss of more than 10 kg body weight 1.5 months. The research have shown the obstruction's formation of the stomach's output part, small bowel obstruction at several levels, as well as thickening of the bladder wall and the unilateral expansion of the ureter. Against the backdrop of strengthening of immunosuppressive therapy these lesions completely regressed

Synthesis, crystal structure and electrophysical properties of triple molybdates containing silver, gallium and divalent metals

A possibility of the triple molybdates formation with both NASICON-like and NaMg3In(MoO4)5 structures in the Ag2MoO4–AMoO4–Ga2(MoO4)3 (A = Mn, Co, Zn, Ni) systems was studied by powder X-ray diffraction analysis. It was established that NASICON-like phases Ag1−xA1−xGa1+x(MoO4)3 are not formed. The triple molybdates AgA3Ga(MoO4)5 (A = Mn, Co, Zn) isostructural to triclinic NaMg3In(MoO4)5 (sp. gr. P`1, Z = 2) were synthesized and characterized. The structure of the obtained compounds was refined for AgZn3Ga(MoO4)5  according to the powder data by the Rietveld method. The structure consists of MoO4 tetrahedra, couples of edge-shared M(1)O6 octahedra, and trimers of edge-shared M(2)O6-, M(3)O6- and M(4)O6 octahedra, which are linked by the common vertices to form a 3D framework. High-temperature conductivity measurements revealed that the conductivity of AgMn3Ga(MoO4)5 at 500 °С reaches 10-2 S/cm, which is close to one of the known NASICON-type ionic conductors

A Modern View of Anomalies in the Metal Groups of the Periodic System of D.I.Mendeleev

The article is devoted to the 150th anniversary of the Periodic Table of Chemical Elements by D.I.Mendeleev. The fundamental law of nature, discovered by D.I.Mendeleev has anomalies and paradoxes associated with certain groups of metals. When studying the physical and chemical properties of complex metal compounds, many discrepancies can be found, namely, the location of elements in groups, which primarily relate to metals with different valences. By studying the approaches and methods for predicting the arrangement of chemical elements, it can be established that D.I.Mendeleev eliminated many differences for some metals during the formation of the Periodic system of chemical elements. D.I.Mendeleev developed a principle that excludes such errors when finding and discovering new elements. Analytical studies conducted by a Russian scientist helped to calculate the atomic masses and describe the properties of three elements not known at that time – «eka-boron», «eka-silicon», «eka-aluminum», the existence of which was proved and confirmed by subsequent discoveries of scandium, germanium, boron, and gallium. The paper provides a significant assessment of the forecasting of metals in various groups of the periodic system. Changes in the properties of some metals significantly influenced their location in the table of D.I.Mendeleev

Metallurgists of the Mining university and development of monetary industry. 245 years of history

Monetary industry combines several stages of metallurgical processes, which are continuously improved with the development of technology and the level of knowledge in the field of non-ferrous metals. The graduates of the Mining Institute, metallurgists of several generations, took part in establishment the Mint and development of technology to produce coins. Since January 24, 1718, when Peter the Great signed the decree «on production of small and large coins ...», the history of the monetary system of Russia and the coining of the first silver rubles began, which subsequently formed the basis of money relations. Twenty-four graduates of the mining and metallurgical departments of the Mining University worked as heads and münzmeister of the Mint. Silver rubles and work of Russian münzmeisters provided financial stability in Tsarist Russia from 1718 to 1917 and laid the foundation for further development of the monetary industry, taking into account new knowledge in the field of enrichment, preparation of polymetallic ores and their melting, and also stamping and processing of precious metals. This is the history of Russia and St. Petersburg, it combined the history of the Mining University, which this year will be 245 years old. It is of scientific interest to restore historical justice and update the methodological knowledge in the field of technology of monetary industry and metallurgical processes

Infective endocarditis and COVID-19: the impact of SARS-CoV-2 infection on diagnostics, course, and prognosis

Aim. To study the impact of coronavirus disease 2019 (COVID-19) pandemic on hospitalization rates, diagnosis, and outcomes of infective endocarditis (IE) with a subanalysis of IE course in combination with COVID-19.Material and methods. This prospective cohort study included 168 patients with definite or probable IE (DUKE 2015) hospitalized in the V.V. Vinogradov City Clinical Hospital from July 2017 to July 2022. All patients underwent a conventional examination in accordance with current clinical guidelines. We studied clinical, paraclinical and etiological parameters, as well as outcomes.Two clinical observations of the combination of IE and COVID-19 are presented.Results. When assessing the local registry of patients with IE, a trend towards an increase in hospitalizations rate of IE in 2021-2022 was shown, with a decrease during the period of long-term lockdowns in Moscow and a subsequent surge after their cancellation. Patients with IE during the COVID-19 pandemic had a more favorable clinical profile, a 2-fold increase in IE diagnosis (due to late hospitalization), frequent detection of Staphylococcus aureus MSSA (32,6%), and frequent surgical treatment (up to 87,6% with a combination of IE and COVID-19), as well as high in-hospital mortality, but without a tendency to increase (30,4%). Clinical observations of IE and COVID-19 combination are presented, which demonstrates the contribution of COVID-19 as the only risk factor for native tricuspid valve IE in a patient without predisposing causes, as well as a factor in the unfavorable prognosis for native aortic valve IE after the addition of COVID-19, which led to lethal outcome.Conclusion. The present study demonstrates the profile of patients with IE and COVID-19 depending on the epidemiological situation of COVID-19 and the association with SARS-CoV-2 infection. The data obtained make it possible to discuss the potential relationship between COVID-19 and IE. The "endocarditis team" determines the timely implementation of surgery and the absence of an increase in inhospital mortality, regardless of the epidemiological situation

Effect of Antibiotic Therapy on the Sensitivity of Etiological Diagnostic Methods in Patients with Infective Endocarditis after Surgery

Aim. Assessment of impact  of the duration  of preoperative  antimicrobial  therapy  (AMT) on the sensitivity  of microbiological examination and polymerase  chain reaction (PCR) of blood/tissues of resected valves in operated patients with infective endocarditis  (IE).Materials and methods. 52 operated patients with active IE were included prospectively (Duke criteria, 2015). All patients underwent microbiological examination of blood  before  admission  to the cardiac  surgery  hospital,  as well as parallel  simultaneous microbiological examination and  PCR  of blood/tissues of excised  valves,  followed  by Sanger  sequencing. The duration  of preoperative  treatment  was  calculated  from the first day of AMT according to IE diagnosis to the day of surgery.Results. The causative agent of IE was established in 84.6% (n=44) patients by means of complex etiological diagnosis. A significant  decrease in the sensitivity of microbiological examination of venous blood was revealed when performed  in the period before and after hospitalization to a surgical hospital (up 44.2% to 17.3%, p<0.05). When comparing microbiological examination of blood/tissues of resected valves and PCR of blood/tissues of resected valves, molecular biological  methods demonstrated the greatest sensitivity, with a great advantage when examining the tissues of resected valves (17.3% and 19.2% vs. 38.5% and 75.0%, respectively;  p<0.001). The microbiological examination of venous blood performed  at an early date before admission  to the cardiac  surgery  hospital was comparable in sensitivity to the PCR blood test performed  at a later date after prolonged AMT,  and significantly less sensitive in relation to the PCR of resected valve tissues [44.2% and 38.5% (p>0.05) vs. 75.0% (p<0.05)]. In course of AMT 1-28 days,  there were comparable results of microbiological examination with PCR blood examination and significantly better results of PCR of resected valve tissues [31.0% and 34.5% and 41.4% (p>0.05) vs 72.4% (p<0.001), respectively], and with AMT ≥ 29 days, microbiological examination of any biological  material was negative  in all patients,  and PCR of blood/tissues of resected valves retained high sensitivity (0% and 0% vs. 34.8% and 78.3%, respectively; p<0.01).Conclusion. Long-term preoperative AMT significantly reduced the sensitivity of microbiological examination of resected valve blood/tissue in operated patients with IE, whereas PCR of resected valve blood/tissue was highly sensitive even with preoperative AMT for more than 29 days

Twisted Nanotubes of Transition Metal Dichalcogenides with Split Optical Modes for Tunable Radiated Light Resonators

Synthesized micro- and nanotubes composed of transition metal dichalcogenides (TMDCs) such as MoS$_2$ are promising for many applications in nanophotonics, because they combine the abilities to emit strong exciton luminescence and to act as whispering gallery microcavities even at room temperature. In addition to tubes in the form of hollow cylinders, there is an insufficiently-studied class of twisted tubes, the flattened cross section of which rotates along the tube axis. As shown by theoretical analysis, in such nanotubes the interaction of electromagnetic waves excited at opposite sides of the cross section can cause splitting of the whispering gallery modes. By studying micro-photoluminescence spectra measured along individual MoS$_2$ tubes, it has been established that the splitting value, which controls the energies of the split modes, depends exponentially on the aspect ratio of the cross section, which varies in "breathing" tubes, while the relative intensity of the modes in a pair is determined by the angle of rotation of the cross section. These results open up the possibility of creating multifunctional tubular TMDC nanodevices that provide resonant amplification of self-emitting light at adjustable frequencies

Association of Heart Rate Variability with the Psychosocial Stress Level in Men 41-44 Years Old Living in Moscow

Aim. Research of the association of heart rate variability (HRV) with the level of psychosocial stress (PS) and other indicators of the risk of cardiovascular diseases in a sample of 41-44-year-old men living in Moscow.Material and methods. A total of 299 men aged 41-44 years were examined. The study included a clinical examination and a survey using a standard questionnaire. The categorization of risk factors (RF) for cardiovascular diseases (CVD) was carried out in accordance with generally accepted criteria The psychosocial stress was assessed using the Reeder scale. Depending on the psychosocial stress level, all surveyed men were divided into 3 groups by terciles: group 1 (3,28-4,0 points) – mild stress, group 2 (2,71-3,14) – moderate stress, group 3 (1,28-2,57) – severe stress. The analysis of HRV was performed on the basis of a short recording of an electrocardiogram using the original software package.Results. Nonparametric ANOVA showed that the mean [M (95% CI)] values of the HRV time domain (SDNN, rMSSD and the state of regulatory reserves) were lower in the group of men with high PS compared with the group with low PS [25.3 ms (20.9-29.7) versus 40.5 ms (30.7-50.3), p=0.007; 29.5 ms (24.6-34.3) versus 49.5 ms (36.7-62.3), p=0.030; and 46.7 (44.7-48.6) versus 49.7 (48.1-51.4), p=0.019; respectively]. On the contrary, the mean values [M (95% CI)] of the integral indicators of HRV (SI and IVR) were higher in the group of men with high PS [635.8 c.u. (556.2-715.4) versus 488.9 (423.8-554.1), p=0.005; 1172.6 (1045.1-1300.1) versus 904.7 (790.0-1019.4), p=0.003; respectively]. The results of correlation and multiple regression analysis confirmed that these HRV indicators are statistically significantly associated not only with PS, but also with other indicators (age, waist / hip ratio, diastolic blood pressure). However, their predictive value turned out to be low, and the proportion of the explained variance of HRV indices ranged from 2.5 to 13.1%.Conclusion. The weakening of the autonomous regulation of the heart rate with a decrease in the activity of the parasympathetic link, the activation of the central circuit of regulation with the prevalence of sympathetic influences, a decrease in the functional reserves of the heart rate regulation system are associated with an increase in the level of PS and other indicators of the risk of cardiovascular diseases

Clinical and diagnostic value of including PCR blood test in the traditional algorithm for identifying causative agents of infective endocarditis: a cohort study of 124 patients

Background. If infective endocarditis (IE) is suspected, the determination of the etiology is of fundamental importance for the verification of the disease and the appointment of effective therapy. Microbiological diagnostic features are important, but they often need to be supplemented by culture-independent studies of pathological agents. Aim. To investigate of the diagnostic advantage and value of quantitative analysis of molecular biological methods (polymerase chain reaction PCR, sequencing) in addition to microbiological examination of whole venous blood in IE. Materials and methods. We examined 124 patients with suspected or significant IE (DUKE 2015) hospitalized in the Vinogradov City Clinical Hospital (20152021). All patients underwent parallel microbiological (cultural) and molecular biological (PCR or PCR followed by sequencing) examination of venous whole blood samples. Results. The introduction of an early parallel PCR study into the algorithm for the etiological diagnosis of IE made it possible to obtain an additional advantage in 43/124 (34.7%) patients, which made it possible to exclude unreliable results in the determination of CoNS skin commensals and pathogens atypical for IE or contamination and identify the true pathogens, and also for the first time to isolate the etiopathogenetic pathogen with a negative microbiological study. It was shown that in IE associated with CoNS, the association with the disease was confirmed by PCR in 21.4% (3/14) and refuted in 71.4% (10/14). The coincidence of the results of microbiological and PCR studies of blood samples was obtained only in 35/95 (36.8%). Positive results of PCR analysis of blood of biological material with negative results of culture were obtained in 22/51 (43.1%), of which 2/22 (9.0%) were able to confirm the presence of Bartonella spp DNA. The presented complex algorithm made it possible to significantly increase the possibility of intravital identification of the pathogen in the blood from 58.9 to 76.6%. IE with unknown etiology was present in 29/124 (23.4%) patients. A parallel PCR study allowed timely correction of antibiotic therapy in 43/124 (34.7%) patients. Conclusion. Expansion of indications for the use of PCR studies, primarily whole venous blood samples, is justified, not only in IE with negative results of microbiological examination, but also as a control method for the reliability of the results of traditional (cultural) diagnostic methods