Saposin D acting on macrophage bacteriostatic function in experimental tuberculosis infection

The protection against tuberculosis infection is largely determined by the ability of host tissue macrophages to limit the growth and spread of mycobacteria. Able to multiply within the host macrophages, mycobacteria have developed a number of protective mechanisms preventing phagosome-lysosome fusion, thereby evading damaging effects of lysosomal enzymes. Saposins are small, acidic, thermostable, non-enzymatic glycoproteins that participate as co-fac-tors in degradation of short oligosaccharide head group glycosphingolipids. Saposins A, B, C and D are formed in acidic endosomes due to cleavage of initial prosaposin molecule. The effect of saposins on human immune response is mediated by their involvement in presenting mycobacterial antigens on CD1 molecules. Preliminary studies with electron microscopy allowed to uncover saposin D-bound damaging effect on Mycobacterium tuberculosis in acidic environment. These data allowed us to suggest that saposin D is an important protective component fighting against TB infection. The aim of the study was to explore how saposin D deficiency might affect formation of anti-tuberculosis immune response and ability of macrophages to inhibit M. tuberculosis growth. Materials and methods. Interstitial pulmonary macrophages and peritoneal macrophages were isolated from wild type C57BL/6 strain and saposin D deficient C57BL/6-SapD-/- mouse strains. Results. It was found that as compared to macrophages from mice, macrophages from wild type strain significantly better controlled mycobacteria growth in vitro. To study an opportunity of compensating for deficient saposin D in peritoneal macrophages from C57BL/6-SapD-/- mice, a saposin D gene-bearing lentiviral vector was created. Transfection of SAPD-deficient peritoneal macrophages with expression vector compensated for saposin D deficiency in such cells and restored bactericidal function. The mechanisms of action for current anti-TB drugs are mediated by various metabolic pathways in mycobacteria (inhibited biosynthesis of fatty acids, arabinogalactan, peptidoglycan and protein; inhibition of DNA-dependent processes, proton pumps and cytochrome P450-dependent monooxygenases). Conclusion. It was shown that saposin D deficiency affects activation of macrophage bactericidal function in vitro. Our study data may be a prerequisite for biologically substantiated potential of using a vector construct bearing natural human protein gene such as saposin D, as a new anti-tuberculosis drug

Interleukin-11 Drives Early Lung Inflammation during Mycobacterium tuberculosis Infection in Genetically Susceptible Mice

IL-11 is multifunctional cytokine whose physiological role in the lungs during pulmonary tuberculosis (TB) is poorly understood. Here, using in vivo administration of specific antibodies against IL-11, we demonstrate for the first time that blocking IL-11 diminishes histopathology and neutrophilic infiltration of the lung tissue in TB-infected genetically susceptible mice. Antibody treatment decreased the pulmonary levels of IL-11 and other key inflammatory cytokines not belonging to the Th1 axis, and down-regulated IL-11 mRNA expression. This suggests the existence of a positive feedback loop at the transcriptional level, which is further supported by up-regulation of IL-11 mRNA expression in the presence of rIL-11 in in vitro cultures of lung cells. These findings imply a pathogenic role for IL-11 during the early phase of Mycobacterium tuberculosis-triggered disease in a genetically susceptible host

Preparation and use of transplantable cell line of newborn rabbits for reproduction of viruses

The purpose of the study was development of a way of receiving culture of cells from bodies of newborn rabbits for a reproduction of production strains of viruses

Safety and Effectiveness of Pharmacologic Conversion of Atrial Fibrillation and Flutter: Results of Multicenter Trial. Part II: Assessment of Safety

Aim. We aimed to assess safety and effectiveness of class III antiarrhythmic drug Refralon for conversion of atrial fibrillation (AFib) and flutter (AFl) in post-registration trial and to compare data of primary center (National medical research center in cardiology) with data of other hospitals.Material and Methods. We performed retrospective cohort study in 727 patients (451 enrolled in primary center and 276 enrolled in other hospitals) admitted between June 24, 2014 and June 24, 2019. Refralon was administered for conversion of AFib and AFl in intense care units in escalating doses (10-30 micrograms/kg) intravenously.Results. Conversion of AFib and AFl into sinus rhythm was achieved in 53,6% after administration of 10 mcg/kg dose, in 73% after administration of 20 mcg/kg dose and in 91,6% after administration of Refralon in dose up to 30 mcg/kg. No mortality and no major adverse cardiac events registered in our study. Asystole >3.0 sec observed in 5% (35 of 727) of patients): in 5% (24 of 451) of patients enrolled in primary center and in 4% (11 of 276) of patients enrolled in other hospitals; 95% confidence interval (CI) [-0.09; 0.113]. Asystole> 5.0 s observed in 1.7% of patients who further required non-urgent implantation of a permanent pacemaker due to manifestations of sinus node dysfunction. Cardiac conduction disturbances (exclusively sinus bradycardia) were registered in 7% (53 of 727) patients: in 8% (37 of 451) of patients enrolled in primary center and in 6% (17 of 276) of patients enrolled in other hospitals; 95% CI: [-0.1; 0.15]. Only 0.14% of patients had symptomatic sinus bradycardia that resolved after atropine injection. Ventricular arrhythmias (exclusively Torsade de pointes tachycardia in excessive QT interval prolongation) were registered in 1.7% (12 of 727) patients: in 2% (9 of 451) of patients in primary center and in 1% (3 of 276) of patients of other hospitals; 95% CI: [-0.06; 0.08]. QTc interval prolongation to values >500 ms documented in 19% (138 of 727) of patients: in 21% (95 of 451) of patients in primary center and in 16% (43 of 276) of patients in other hospitals; 95% CI: [-0.13; 0.24].Conclusion: In post-registration multicenter trial Refralon demonstrated good safety profile in conversion of AFib and AFl. Potential risk of TdP tachycardia mandates precautions with the use of the drug. In other hospitals Refralon did not demonstrate lower safety than in primary medical center

Флюоресцентная диагностика и фотодинамическая терапия рака кожи с препаратом аласенс

The results of treatment in patients with skin cancer using the method of photodynamic therapy (PDT) with alasens are represented in the article. The study enrolled 25 patients with stage 1 tumor including 23 patients with previously untreated tumors and 2 – with recurrent disease. Superficial tumor was diagnosed in 17 patients and 8 patients had nodal tumor. Alasens was used locally as application of 20% ointment on involved skin area with 6h exposure. The PDT session was performed on a single occasion immediately after the end of exposure (power density of laser irradiation of 50–100 mW/cm2, light dose – 150–200 J/cm2). All patients had fluorescence diagnosis (FD) prior to application of the ointment and before PDT. The results of FD showed that intensity of porphyrin fluorescence in tumor prior to administration of alasens had near no difference from intensity of porphyrin fluorescence in normal skin (12.5±0.7 and 10.0±0.7 r.u., respectively). Six hours after application of the ointment with alasens the fluorescence intensity of protoporphyrin IX increased almost 5-fold (59.7±5.3 r.u.), the fluorescence intensity in normal skin remained near baseline level during the follow-up period (maximally 11.6±1.0 r.u.). Two months after PDT the complete tumor regression was confirmed in 21 patients, partial – in 3 and stabilization of tumor growth in 1 patient. In addition, patients with superficial disease had complete regression in 94.1% of cases and partial regression in 5.9% while for patients with nodal tumor – 62.5% and 25%, respectively, stabilization – in 12.5%. В статье приведены результаты лечения больных раком кожи методом фотодинамической терапии (ФДТ) с препаратом аласенс. В исследование включены 25 пациентов с I стадией опухолевого процесса, в том числе 23 пациента с ранее не леченной опухолью и 2 – с рецидивом заболевания. У 17 пациентов была диагностирована поверхностная форма опухоли, у 8 – узловая. Аласенс применяли местно, в виде аппликации 20%-ой мази, на поражённый участок кожи с экспозицией в течение 6 ч. Сеанс ФДТ проводили однократно сразу после завершения экспозиции (плотность мощности лазерного излучения 50–100 мВт/см2, плотность энергии – 150–200 Дж/см2). Всем пациентам проводилась флюоресцентная диагностика (ФД) до аппликации мази и перед проведением ФДТ. Результаты ФД показали, что интенсивность флюоресценции порфиринов в опухоли до введения аласенса практически не отличается от флюоресценции порфиринов в здоровой коже (12,5±0,7 и 10,0±0,7 отн. ед., соответственно). Через 6 ч после начала аппликации мази с аласенсом интенсивность флюоресценции протопорфирина IX в опухоли возрастает почти в 5 раз (59,7±5,3 отн. ед.), интенсивность флюоресценции в здоровой коже остается практически на уровне исходных значений в течение всего периода наблюдения (максимально 11,6±1,0 отн. ед.). Через 2 мес. после проведения ФДТ полная регрессия опухоли была подтверждена у 21, частичная – у 3 и стабилизация – у 1 пациента. При этом у больных с поверхностной формой заболевания в 94,1% случаев была зарегистрирована полная регрессия опухоли и в 5,9% – частичная регрессия, в то время как у больных с узловой формой – в 62,5% и в 25% соответственно; стабилизация – в 12,5%.

Kinetic regulation of multi-ligand binding proteins

Background: Second messengers, such as calcium, regulate the activity of multisite binding proteins in a concentration-dependent manner. For example, calcium binding has been shown to induce conformational transitions in the calcium-dependent protein calmodulin, under steady state conditions. However, intracellular concentrations of these second messengers are often subject to rapid change. The mechanisms underlying dynamic ligand-dependent regulation of multisite proteins require further elucidation. Results: In this study, a computational analysis of multisite protein kinetics in response to rapid changes in ligand concentrations is presented. Two major physiological scenarios are investigated: i) Ligand concentration is abundant and the ligand-multisite protein binding does not affect free ligand concentration, ii) Ligand concentration is of the same order of magnitude as the interacting multisite protein concentration and does not change. Therefore, buffering effects significantly influence the amounts of free ligands. For each of these scenarios the influence of the number of binding sites, the temporal effects on intermediate apo- and fully saturated conformations and the multisite regulatory effects on target proteins are investigated. Conclusions: The developed models allow for a novel and accurate interpretation of concentration and pressure jump-dependent kinetic experiments. The presented model makes predictions for the temporal distribution of multisite protein conformations in complex with variable numbers of ligands. Furthermore, it derives the characteristic time and the dynamics for the kinetic responses elicited by a ligand concentration change as a function of ligand concentration and the number of ligand binding sites. Effector proteins regulated by multisite ligand binding are shown to depend on ligand concentration in a highly nonlinear fashion

Design and technological solutions in development of highly efficent processing technology pressure

On the basis of long-term experience of introduction of processes of volume and sheet stamping comparative features of development of technologies and the form-building tool, and, including, the providing shaped details with the application of the smaller deforming forces are presented when saving of the set characteristics of durability and plasticity, and also economy of materials. Rational technological process can be created only in the careful analysis of a set of known and original ways of forming of preparations and control of structure of metal and a form of a forging

Selection schemes of formation hollow parts with the taperid surface

It describes different technologies obtained by cold forming of hollow parts with conical surfaces of solid and tubular billets, analyzed the advantages and disadvantages of certain methods of deformation. The results of mathematical modeling using a specialized system of finite-element Super Forge and the method of forming the upper assessment process hollow parts with internal conical surface. Conclusions on the possibility of reducing the forces of deformation due to changes in construction equipment