[Long-term treatment of morphologically verified myocarditis: successes and probable errors. Case report]

Diagnosis and treatment of myocarditis can be challenging, including determining indications for heart transplantation. We present a 6-year medical history of a 54 years old patient with severe morphologically verified viral-negative lymphocytic myocarditis and systemic manifestations (onset of hemorrhagic vasculitis) combined with moderate coronary atherosclerosis, which regressed according to repeated coronary angiography. For 5 years, the patient received immunosuppressive therapy with methylprednisolone and azathioprine with a significant improvement. Repeated relapses of atrial fibrillation required correction of basic therapy and plasmapheresis. The disease was complicated by thyrotoxicosis and multi-organ dysfunction; the autopsy showed persistent myocarditis activity. The myocarditis is a chronic condition and requires a review of the treatment strategy at each stage.

Life expectancy loss due to the COVID-19 pandemic exemplified by Moscow

 

There is high excess mortality against the background of the pandemic in Moscow (an increase of 36.2% against 18.1% on the national average). According to preliminary data, the loss of life expectancy is 3.1 years for Muscovites (from 78.9 years in 2019 to 76.2 years in 2020) and 1.9 years for the Russian population (from 73.4 to 71.5 years). As in other countries, elderly people suffering from chronic diseases were the most affected. The age-specific mortality rates in 2020 are significantly higher than those of 2019 in the age interval of 45 years and older as well as among children 10-14 years old and young people 25-29 years old. The maximum increase in mortality was recorded in age groups over 80 years old in males and 25-29 years in females. At the same time, infant mortality in Moscow has significantly decreased which is associated with a sharp decrease in the share of births among nonresidents (it exceeded a quarter of all births in the capital in 2019). The reduction in labor migration due to the closure of borders has led to a decrease in births among nonresidents. Using the decomposition method, it was shown that the greatest negative contribution to the loss of life expectancy in both sexes was made by mortality in the age group of 70-74 years which reduced life expectancy by 0.36 years for men and 0.27 years for women. Life expectancy decreased by 0.25 and 0.19 years due to death of men and women aged 75-79 years and by 0.09 and 0.02 years due to death of people aged 25-29 years. Reducing infant mortality yielded a life expectancy gain of 0.15 years for men and 0.11 years for women. These results changed the assessment of the significance of shifts in mortality in age groups. Analysis of changes in age-specific mortality and evaluation of its impact on changes in life expectancy shows different perspectives of the problem, which is important for making adequate decisions in health.

Key messages

The reduction in labor migration due to the closure of borders has led to a decrease in births among nonresidents. Analysis of changes in age-specific mortality and evaluation of its impact on changes in life expectancy shows different perspectives of the problem.

Role of NUDIX Hydrolases in NAD and ADP-Ribose Metabolism in Mammals

Proteins of the NUDIX hydrolase (NUDT) superfamily that cleave organic pyrophosphates are found in all classes of organisms, from archaea and bacteria to higher eukaryotes. In mammals, NUDTs exhibit a wide range of functions and are characterized by different substrate specificity and intracellular localization. They control the concentration of various metabolites in the cell, including key regulatory molecules such as nicotinamide adenine dinucleotide (NAD), ADP-ribose, and their derivatives. In this review, we discuss the role of NUDT proteins in the metabolism of NAD and ADP-ribose in human and animal cells.

The Regulatory Role of NAD in Human and Animal Cells

Nicotinamide adenine dinucleotide (NAD) and its phosphorylated form NADP are the major coenzymes in the redox reactions of various essential metabolic pathways. NAD+ also serves as a substrate for several families of regulatory proteins, such as protein deacetylases (sirtuins), ADP-ribosyltransferases, and poly(ADP-ribose) polymerases, that control vital cell processes including gene expression, DNA repair, apoptosis, mitochondrial biogenesis, unfolded protein response, and many others. NAD+ is also a precursor for calcium-mobilizing secondary messengers. Proper regulation of these NAD-dependent metabolic and signaling pathways depends on how efficiently cells can maintain their NAD levels. Generally, mammalian cells regulate their NAD supply through biosynthesis from the precursors delivered with the diet: nicotinamide and nicotinic acid (vitamin B3), as well as nicotinamide riboside and nicotinic acid riboside. Administration of NAD precursors has been demonstrated to restore NAD levels in tissues (i.e., to produce beneficial therapeutic effects) in preclinical models of various diseases, such as neurodegenerative disorders, obesity, diabetes, and metabolic syndrome.

Subcellular Distribution of NAD+ between Cytosol and Mitochondria Determines the Metabolic Profile of Human Cells

The mitochondrial NAD pool is particularly important for the maintenance of vital cellular functions. Although at least in some fungi and plants, mitochondrial NAD is imported from the cytosol by carrier proteins, in mammals, the mechanism of how this organellar pool is generated has remained obscure. A transporter mediating NAD import into mammalian mitochondria has not been identified. In contrast, human recombinant NMNAT3 localizes to the mitochondrial matrix and is able to catalyze NAD(+) biosynthesis in vitro. However, whether the endogenous NMNAT3 protein is functionally effective at generating NAD(+) in mitochondria of intact human cells still remains to be demonstrated. To modulate mitochondrial NAD(+) content, we have expressed plant and yeast mitochondrial NAD(+) carriers in human cells and observed a profound increase in mitochondrial NAD(+). None of the closest human homologs of these carriers had any detectable effect on mitochondrial NAD(+) content. Surprisingly, constitutive redistribution of NAD(+) from the cytosol to the mitochondria by stable expression of the Arabidopsis thaliana mitochondrial NAD(+) transporter NDT2 in HEK293 cells resulted in dramatic growth retardation and a metabolic shift from oxidative phosphorylation to glycolysis, despite the elevated mitochondrial NAD(+) levels. These results suggest that a mitochondrial NAD(+) transporter, similar to the known one from A. thaliana, is likely absent and could even be harmful in human cells. We provide further support for the alternative possibility, namely intramitochondrial NAD(+) synthesis, by demonstrating the presence of endogenous NMNAT3 in the mitochondria of human cells.

[A new class of small RNP (alpha-RNP) containing antisense RNA in K-562 cells. I. Their characteristics and changes during erythroid differentiation]

A new class of small RNP (alpha-RNP) has been detected and identified in nuclei and cytoplasm of A-562 erythroid leukemia cell line; these RNPs have a characteristic spectrum of proteins containing conservative and specific components and a special RNA component, which contains a small antisense component (alpha-RNA), a homolog of short dispersed Alu repeats. alpha-RNP is highly stable, tightly associated with chromatin in the nucleus, and is found in the free state in cytoplasm. The composition of nuclear and cytoplasmic alpha-RNP differ and have a specific pattern of changes in response to dimethylsulfoxide, an agent causing differentiation.

[Clinical picture and treatment of herpes zoster in children]

The symptoms and the course of herpes zoster are analyzed in 85 children aged 5 months to 15 years. Many systems of the body were shown to be involved in the process of the disease which is characteristic of neuroviral infections. The authors postulate the etiologic unity of chicken pox and herpes zoster as two clinical forms of the same epidemic process. The questions of treatment are outlined.