EXAMINING LOCALLY EXPRESSED mRNA OF INFLAMMATORY MEDIATOR GENES IN A MODEL OF RETINAL PIGMENT EPITHELIUM ATROPHY AND RETINAL DEGENERATION INDUCED BY SUBRETINAL SALINE INJECTION IN RABBITS

Degenerative-dystrophic retinal diseases, particularly age-related macular degeneration (AMD), are now considered to be the lead cause of blindness and low vision in developed countries, with a steadily increasing trend. Recent publications provide evidence for the involvement of inflammatory mechanisms in TMD development and progression unveiled due to advances in innate and adaptive immunity research. However, the immunopathogenesis of atrophic AMD form, “geographic atrophy” (GA) remains largely unstudied. Objective: to investigate local mRNA expression of inflammatory cytokines IL-1β, IL-18, CCL2/MCP-1 in a model of RPE atrophy induced after subretinal injection of 0.9% sodium chloride solution in experimental rabbits. The investigation was carried out in tissue complex retina-RPE-choroid (TC) samples isolated from eyes of 23 albino New Zealand rabbits after modeling RPE atrophy by subretinal injection of 0.9% sodium chloride solution and 5 healthy rabbits lacking eye lesions. Animals in the experimental group (one week before surgical intervention, in the early period, and in the period of sustained RPE atrophy formation) and controls were subjected to optical coherence tomography (OCT) and ocular fundus autofluorescence (FAF). Evaluation of proinflammatory cytokine gene expression levels in TC was performed by RT-PCR. Results. Subretinal injection of 0.01 ml of 0.9% sodium chloride solution induced experimental RPE atrophy development in rabbits vs. control that was associated with multidirectional changes of IL-1β, IL-18, MCP-1/CCL2 gene mRNA expression. Three types of response in the TC, formed during development of atrophic changes and determined by the value of local cytokine gene expression were characterized: 1) hypo/ no response – decreased/no expression; 2) normal response – moderate increase; 3) hyper response – overexpression. 69.6% of animals with persistent atrophy had a moderate to hypertrophic increase in locally expressed mRNA MCP-1/CCL2, whereas 30% cases had significantly increased IL-1β mRNA expression – factors damaging the blood-retinal barrier and contributing to posterior segment immune privilege. It should be taken into account while developing new strategies for treatment of ophthalmic pathology, in particular the currently actively studied and tested options for RPE stem cell transplantation into subretinal space. The data obtained may be useful to investigate various types of RPE atrophy and develop new strategies of ophthalmopathology treatment in preclinical studies

The use of Flash glucose monitoring in children with type 1 diabetes mellitus in real clinical practice

BACKGROUND: In 2018, a Frestyle Libre flash glucose monitoring system (FGM) appeared in Russia and became a potential alternative to the traditional CGM. Studies carried out to date have shown the advantages of FGM over SMBG, but only a few of them relate to real clinical practice, especially in children with type 1 diabetes.OBJECTIVE: To evaluate the efficacy of FGM in children with T1DM in relation to glycemic control indicators, the occurrence of severe hypoglycemia and diabetic ketoacidosis, as well as the satisfaction of patients and their parents with the use of FGM.MATERIALS AND METHODS: Single-center, prospective, observational cohort study. Children 4–18 years old with T1DM and HbA1c level less than 10.0% were invited to participate in the study on intensified insulin therapy (by MDI or CSII). The duration of the patient’s participation in the study was 6 months. At baseline and every 3 months thereafter, face-to-face consultations were conducted with an assessment of the general condition, HbA1c study, an assessment of glycemic indicators, progress in relation to glycemic control targets and correction of the therapy. A total of 228 patients (110 boys and 118 girls) who met the inclusion criteria were included in the study. The median age was 11.2 (8.6–14.7) years, the duration of type 1 diabetes was 3.8 (2–7.1), 136 patients received insulin therapy by CSII for 1.3 (0.8–2.6) years.RESULTS: In the general group of patients, 3 and 6 months after the start of FGM use, the HbA1c values decreased statistically significantly by 0.2%. In addition, the number of children with HbA1c <7.5% increased by 6.1 and 4.9% at 3 and 6 months, respectively, but these changes were not statistically significant. The number of cases of DKA when using FGM decreased by 74%, and the number of cases of severe hypoglycemia by 83%, thus the number of episodes decreased by 4 and 6 times, respectively. Patients and / or their parents rated the ease of use and their experience with FGM on a scale from 0 (strongly agree) to 4 (strongly disagree). The majority of children and parents positively (0 or 1) assessed the convenience of installing and wearing the sensor (72.7–98.2%) using the FGM system in general (75.0–96.4%) and in comparison with the SMBG glucometer (92.3–98.2%).CONCLUSION: The installation and use of FGM is convenient and comfortable for the vast majority of children and parents, while compared to SMBG, the use of FGM is more convenient and simpler, and glucose measurement is much faster and less painful

Clinical, hormonal and molecular-genetic characteristics of monogenic diabetes mellitus associated with the mutations in the <i>INS</i> gene

Background: Currently more than 50 mutations of the INS gene are known to affect the various stages of insulin biosynthesis in the beta cells of the pancreas. However only individual cases of diabetes mellitus (DM) associated with heterozygous mutations in the coding region of the INS gene were reported in Russian Federation. We report a group of patients with a clinical manifestation of DM caused by mutations in both coding and non-coding regions of the INS gene. The patients with a mutation in the intron of the INS gene are reported for the first time in Russian FederationMaterials and methods: 60 patients with an isolated course of neonatal DM (NDM), 52 patients with a manifestation of DM at the age of 7–12 months and the absence of the main autoimmune markers of type 1 DM, 650 patients with the MODY phenotype were included in the study. NGS technology was used for molecular genetic research. Author’s panel of primers (Custom DNA Panel) was used for multiplex PCR and sequencing using Ion Ampliseq™ technology. The author’s panel “­Diabetes Mellitus” included 28 genes (13 candidate genes of MODY and other genes associated with DM).Results: 13 heterozygous mutations were identified in 16 probands and 9 relatives. The majority of mutations were detected in patients with PNDM (18.75%) and in patients with an onset of DM at the age of 7–12 months (9.6%). Mutations in the INS gene were detected in 2 patients (0.3%) in the group with the MODY phenotype. Mutations in the INS gene were not detected in patients with transient NDM (TNDM). Analysis of clinical data in patients with PND and onset of diabetes at the age of 7–12 months did not show significant differences in the course of the disease. The clinical characteristics of the cases of MODY10 and diabetes caused by a mutation in the intron of the INS gene are reported in details.Conclusion: The role of INS gene mutations in NDM, MODY, and DM with an onset at the age of 7–12 months was analyzed in a large group of patients. The clinical characteristics of DM due to a mutation in the intron of the INS gene are reported for the first time in the Russian Federation

Диагностика туберкулеза легких в условиях пульмонологического отделения стационара

A clinical case of 23-year old female with pulmonary tuberculosis is described in this article. The patient was admitted to a hospital with preliminary diagnosis of community-acquired pneumonia and negative TB test. Differential diagnosis of pulmonary tuberculosis and community-acquired pneumonia is often difficult and could be more difficult in patients with co-existing specific (Mycobacterium tuberculosis) and non-specific infection in the lungs.Дифференциальная диагностика туберкулеза легких (ТЛ) и пневмонии является сложной проблемой на этапе первичного обследования пациента в терапевтической практике. Представлен клинический случай диагностики ТЛ у 23-летней женщины при поступлении в стационар терапевтического профиля с диагнозом внебольничная пневмония при наличии отрицательных специфических тестов на ТЛ. Диагностика также может быть затруднена при наличии сочетанной специфической (микобактерии туберкулеза) и неспецифической инфекции в зоне воспалительного поражения легких

Intestinal epithelial stem cells do not protect their genome by asymmetric chromosome segregation

The idea that stem cells of adult tissues with high turnover are protected from DNA replication-induced mutations by maintaining the same 'immortal' template DNA strands together through successive divisions has been tested in several tissues. In the epithelium of the small intestine, the provided evidence was based on the assumption that stem cells are located above Paneth cells. The results of genetic lineage-tracing experiments point instead to crypt base columnar cells intercalated between Paneth cells as bona fide stem cells. Here we show that these cells segregate most, if not all, of their chromosomes randomly, both in the intact and in the regenerating epithelium. Therefore, the 'immortal' template DNA strand hypothesis does not apply to intestinal epithelial stem cells, which must rely on other strategies to avoid accumulating mutations

Diabetes mellitus type 1 in childhood

Public organization &ldquo;Russian Association of Endocrinologists&rdquo;. Clinical guidlines

H2AX phosphorylation at the sites of DNA double-strand breaks in cultivated mammalian cells and tissues

A sequence variant of histone H2A called H2AX is one of the key components of chromatin involved in DNA damage response induced by different genotoxic stresses. Phosphorylated H2AX (γH2AX) is rapidly concentrated in chromatin domains around DNA double-strand breaks (DSBs) after the action of ionizing radiation or chemical agents and at stalled replication forks during replication stress. γH2AX foci could be easily detected in cell nuclei using immunofluorescence microscopy that allows to use γH2AX as a quantitative marker of DSBs in various applications. H2AX is phosphorylated in situ by ATM, ATR, and DNA-PK kinases that have distinct roles in different pathways of DSB repair. The γH2AX serves as a docking site for the accumulation of DNA repair proteins, and after rejoining of DSBs, it is released from chromatin. The molecular mechanism of γH2AX dephosphorylation is not clear. It is complicated and requires the activity of different proteins including phosphatases and chromatin-remodeling complexes. In this review, we summarize recently published data concerning the mechanisms and kinetics of γH2AX loss in normal cells and tissues as well as in those deficient in ATM, DNA-PK, and DSB repair proteins activity. The results of the latest scientific research of the low-dose irradiation phenomenon are presented including the bystander effect and the adaptive response estimated by γH2AX detection in cells and tissues

DNA loop anchorage region colocalizes with the replication origin located downstream to the human gene encoding lamin B2.

The recently developed procedure of topoisomerase II-mediated DNA loop excision has been used to analyze the topological organization of a human genome fragment containing the gene encoding lamin B2 and the ppv1 gene. A 3.5 kb long DNA loop anchorage/topoisomerase II cleavage region was found within the area under study. This region includes the end of the lamin B2 coding unit and an intergenic region where an origin of DNA replication was previously found. These observations further corroborate the hypothesis that DNA replication origins are located at or close to DNA loop anchorage regions

Vzaimosvyaz' mezhdu avtonomnoy nevropatiey i bessimptomnymi gipoglikemiyami u patsientov s sakharnym diabetom 1 tipa

Цель. Изучение влияния диабетической автономной невропатии на особенности клинического проявления гипогликемий у больных СД 1 с длительным стажем заболевания. Материалы и методы. Обследовано 64 пациента с СД 1 с длительностью заболевания более 5 лет. Считалось количество эпизодов бессимптомных гипогликемий (1?3 и более эпизодов) в течение периода подкожного мониторирования в течение 3-х дней. Состояние вегетативной нервной системы оценивалось методом исследования вариабельности ритма сердца. При обработке результатов кардиоваскулярных проб в контрольной группе выявлены парасимпатические нарушения вегетативной регуляции. Результаты. В результате проведенного исследования бессимптомные гипогликемии были выявлены у 66% пациентов. Среди больных с длительным стажем сахарного диабета выявляется значительное количество бессимптомных гипогликемий, в том числе и частых повторяющихся эпизодов (3 и более раз на протяжении исследования), что может быть предиктором возникновения тяжелой гипогликемии, требующей посторонней помощи. Наибольшую склонность к частым бессимптомным гипогликемиям, имеют больные с более низким гликированным гемоглобином. Выводы. . Обнаружено, что пациенты с низкой способностью распознавать гипогликемии имеют выраженные автономные нарушения. Отмечена достоверно значимая связь в общей группе больных с бессимптомными гипогликемиями с уровнем гликированного гемоглобина, длительностью сахарного диабета, длительностью ночных гипогликемий, длительностью дневных гипогликемий и максимальной их продолжительностью. Исследование автономной невропатии методом оценки вариативности сердечного ритма является способом выявления группы риска больных с частыми бессимптомными гипогликемиями и синдромом нераспознавания гипогликемий