68 research outputs found
Individual differences in toddlers' social understanding and prosocial behavior: Disposition or socialization?
We examined how individual differences in social understanding contribute to variability in early-appearing prosocial behavior. Moreover, potential sources of variability in social understanding were explored and examined as additional possible predictors of prosocial behavior. Using a multi-method approach with both observed and parent-report measures, 325 children aged 18-30 months were administered measures of social understanding (e.g., use of emotion words; self-understanding), prosocial behavior (in separate tasks measuring instrumental helping, empathic helping, and sharing, as well as parent-reported prosociality at home), temperament (fearfulness, shyness, and social fear), and parental socialization of prosocial behavior in the family. Individual differences in social understanding predicted variability in empathic helping and parent-reported prosociality, but not instrumental helping or sharing. Parental socialization of prosocial behavior was positively associated with toddlers' social understanding, prosocial behavior at home, and instrumental helping in the lab, and negatively associated with sharing (possibly reflecting parents' increased efforts to encourage children who were less likely to share). Further, socialization moderated the association between social understanding and prosocial behavior, such that social understanding was less predictive of prosocial behavior among children whose parents took a more active role in socializing their prosociality. None of the dimensions of temperament was associated with either social understanding or prosocial behavior. Parental socialization of prosocial behavior is thus an important source of variability in children's early prosociality, acting in concert with early differences in social understanding, with different patterns of influence for different subtypes of prosocial behavior
Equilibrative Nucleoside Transporters Mediate the Import of Nicotinamide Riboside and Nicotinic Acid Riboside into Human Cells
Nicotinamide riboside (NR), a new form of vitamin B3, is an effective precursor of nicotinamide adenine dinucleotide (NAD+) in human and animal cells. The introduction of NR into the body effectively increases the level of intracellular NAD+ and thereby restores physiological functions that are weakened or lost in experimental models of aging and various pathologies. Despite the active use of NR in applied biomedicine, the mechanism of its transport into mammalian cells is currently not understood. In this study, we used overexpression of proteins in HEK293 cells, and metabolite detection by NMR, to show that extracellular NR can be imported into cells by members of the equilibrative nucleoside transporter (ENT) family ENT1, ENT2, and ENT4. After being imported into cells, NR is readily metabolized resulting in Nam generation. Moreover, the same ENT-dependent mechanism can be used to import the deamidated form of NR, nicotinic acid riboside (NAR). However, NAR uptake into HEK293 cells required the stimulation of its active utilization in the cytosol such as phosphorylation by NR kinase. On the other hand, we did not detect any NR uptake mediated by the concentrative nucleoside transporters (CNT) CNT1, CNT2, or CNT3, while overexpression of CNT3, but not CNT1 or CNT2, moderately stimulated NAR utilization by HEK293 cells.publishedVersio
Purine nucleoside phosphorylase controls nicotinamide riboside metabolism in mammalian cells
Nicotinamide riboside (NR) is an effective precursor of nicotinamide adenine dinucleotide (NAD) in human and animal cells. NR supplementation can increase the level of NAD in various tissues and thereby improve physiological functions that are weakened or lost in experimental models of aging or various human pathologies. However, there are also reports questioning the efficacy of NR supplementation. Indeed, the mechanisms of its utilization by cells are not fully understood. Herein, we investigated the role of purine nucleoside phosphorylase (PNP) in NR metabolism in mammalian cells. Using both PNP overexpression and genetic knockout, we show that after being imported into cells by members of the equilibrative nucleoside transporter family, NR is predominantly metabolized by PNP, resulting in nicotinamide (Nam) accumulation. Intracellular cleavage of NR to Nam is prevented by the potent PNP inhibitor Immucillin H in various types of mammalian cells. In turn, suppression of PNP activity potentiates NAD synthesis from NR. Combining pharmacological inhibition of PNP with NR supplementation in mice, we demonstrate that the cleavage of the riboside to Nam is strongly diminished, maintaining high levels of NR in blood, kidney, and liver. Moreover, we show that PNP inhibition stimulates Nam mononucleotide and NAD+ synthesis from NR in vivo, in particular, in the kidney. Thus, we establish PNP as a major regulator of NR metabolism in mammals and provide evidence that the health benefits of NR supplementation could be greatly enhanced by concomitant downregulation of PNP activity.publishedVersio
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
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
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
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
Characterisation of an aerosol exposure system to evaluate the genotoxicity of whole mainstream cigarette smoke using the in vitro γH2AX assay by high content screening
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