Vol 12, No 6 (2021)

The article presents a review of the literature on the clinical aspects of assessing vitamin D deficiency in young children by the concentration of 25(OH)D (hydroxycalciferol) in blood serum. The purpose of the review was to familiarize pediatric specialists with the real state of affairs in assessing the clinical significance of diagnosing vitamin D status, its relationship with the prevention of deficient rickets, ways of correcting and choosing the dose of calciferol. A daily dose of 400 IU of vitamin D for young children is effective and safe in preventing deficient rickets. Higher subsidized doses of calciferol have not been shown to be more effective. In addition, they can potentially lead to toxic levels of vitamin D metabolites in the blood. When using lower daily doses (less than 400 IU), an adequate prophylactic effect may not be achieved. Determination of the level of circulating serum hydroxycalciferol, which characterizes the status of vitamin D in the body, is not recommended for routine examination and as a standard for diagnosing deficient rickets in young children. Calciferol has multilateral effects, modulates not only phosphorus-calcium metabolism, but also affects other systems and functions of the body, in particular, ontogenesis and the immune system. According to foreign literature, all infants should receive vitamin D for the prevention of rickets, treatment from the age of one month. This is most reliably identified for children, probably at risk. Convincing data indicating a positive protective effect on diabetes mellitus D on unforeseen pathology, for example, the frequency of exclusion of pneumonia, infectious diarrhea, atopic dermatitis in infancy, has not yet been obtained.

Background. Currently there is a high demand in reliable noninvasive diagnostic technique assessing the physiological parameters of the lungs. We are exploring the three-dimensional ultrafast MRI sequence as a novel diagnostic modality allowing the assessment of regional quantitative perfusion parameters in pulmonary tissue.

Aim. To assess regional differences in quantitative pulmonary perfusion parameters in 10 volunteers with no evidence of interstitial lung disease by computed tomography, clinical, and laboratory data.

Materials and methods. 10 volunteers with no signs of interstitial lung disease were examined by three-dimensional ultrafast dynamic contrast-enhanced MR imaging using 3D T1-weighted images. The values of pulmonary blood flow (PBF), mean transit time (MTT), and pulmonary blood volume (PBV) for the targeted regions of interest were calculated based on the dynamic image series. For calculations, arterial input function (AIF) was used, as well as the time-intensity curves.

Results. The values of PBF, MTT, and PBV showed statistically significant differences between central and peripheral sections of lungs. Provided model can be implemented for quantitative assessment of regional pulmonary perfusion allows it to be used to determine the reliability of PBF, MTT and PBV values.

Conclusions. Three-dimensional ultrafast MRI sequence is a novel diagnostic modality allowing the assessment of regional quantitative pulmonary perfusion parameters in pulmonary tissue, regardless of physiological features of blood supply mechanisms in different lung regions.

Background. Мesocortical and nigrostriatal dopaminergic systems are highly sensitive to stressful events. One of the most adequate models of acute psychogenic stress in animals is the death of a partner upon presentation of a predator.

Aim. To study the content of dopamine (DA), serotonin and their metabolites: dioxyphenylacetic (DOPAC), homovanillic and 5-hydroxyindoleacetic (5-HIAA) acids in the prefrontal cortex, striatum, and ventral tegmental area in rats on days 3, 7, and 14 after the acute psychogenic stress of the death of a partner upon presentation of a predator.

Materials and methods. 28 male Wistar rats were studied. Acute single psychotraumatic situation was used. A group of rats was placed in a tiger python terrarium. One animal died as a result of its nutritional needs, the rest of the rats experienced the death of a partner. The content of monoamines in the brain structures was carried out by high performance liquid chromatography with electrochemical detection.

Results. Changes in the content of monoamines in the prefrontal cortex, striatum, and ventral tegmental area were found on the 7 and 14 days after the presentation of the predator. In the ventral tegmental area on the 7 day, there was an increase in the DOPAC/DA ratio and an increase in the serotonin metabolite 5-HIAA, which reflects an increase in the activity of dopamine and serotonin. In the prefrontal cortex on the 14 day, the DOPAС content and the DOPAС/DA index decreased. The 5-HIAA content in the prefrontal cortex and the 5-HIAA/5-HT value also significantly decreased.

Conclusions. Changes in the metabolism of monoamines after presentation of a predator develop gradually: increase of the dopamine and serotonin activity in the ventral tegmental area was noted on the 7 day after presentation of the predator, decrease in their activity in the striatum and prefrontal cortex only on the 14 day, reflecting the development of depressive states and post-traumatic stress disorder.

Background. The question of the effect of female sex hormones and their analogues on humans and experimental animals is of great interest in medicine.

Aim. The aim of the work was to study the morphological features of the ovaries of the offspring of laboratory mice during the administration of estrogens to the maternal body.

Materials and methods. Female laboratory mice after fertilization were divided into groups: two control and two experimental, which at the stage of development of gestation E11.5 underwent intramuscular, single administration of experimental doses of estrogens. The first experimental group was injected with the synthetic drug synestrol in the form of a 2% oil solution at a total dose of 50 mcg / kg (n = 5; S-50), the first control group was injected with olive oil at a dose of 0.2 μm/kg (n = 5). The second experimental group was injected with a 0.4 ml 0.0005% fulvestrant oil solution at a dose of 100 mcg/kg (n = 5; F-100), the second control group (n = 5) received sterile castor oil at a dose of 0.8 μm/kg.

Results. Persistent morphological changes are observed in the ovaries of the offspring of the first experimental group S-50: an increase in the average area of the cortical substance, a decrease in the area of the medulla, an increase in the average number of yellow bodies, an increase in the average number of luteal cells in the yellow body, a decrease in the total number of follicles and atretic bodies, indicating a violation of the folliculogenesis process, an increase in the average diameter of blood vessels demonstrating increased blood circulation. With the introduction of the drug fulvestrant 100 mcg / kg in the second experimental group F-100, morphological changes in the form of an increase in the average area of the cortical substance, a decrease in the average area of the medulla, sclerosis of the stromal component, accompanied by a restructuring of the vascular network with signs of atresia and cystic degeneration of the follicular epithelium in secondary and tertiary follicles are considered on a slice of the ovaries of the offspring.

Conclusions. The obtained results of the study confirm the urgency of the problem of implementing complex measures aimed at limiting the effects of estrogenetic drugs introduced into the maternal body during pregnancy, in order to prevent adverse effects on the development of the ovaries of offspring.

The article presents up-to-date data on the main pathogenetic mechanisms and features of the new coronavirus infection caused by the SARS-CoV-2 virus. The review highlights the main epidemiological features of infection with SARS-CoV-2 in children at various age periods, features of the immune response and variants of the course of the disease with lung damage, as well as other organs and systems. The clinical and laboratory features of the course of a new coronavirus infection in children are highlighted. It was found that children are less likely to develop severe COVID-19 than adults. More than 95% of all cases of the disease range from asymptomatic course to clinical manifestations of mild and moderate severity. About 2% of children’s patients need hospitalization, including in the intensive care unit and ventilator. However, extrapulmonary manifestations are registered in children more often than in adults, especially from the gastrointestinal tract and circulatory organs. According to numerous authors, the features of the clinical and laboratory course of COVID-19 in pediatric patients are probably associated with a number of factors, among which age-related features of the immune response, the functioning of angiotensin-converting enzyme-2 (ACE-2) used by coronaviruses as a cellular receptor are indicated. Understanding the role of the child population in the dynamics of transmission of infection is important, since children significantly affect the rate of infection spread.

According to scientific research, malignant neoplasms in children are biomedical risk factors for the development of tuberculosis (TB). On the contrary, the occurrence of oncological disease in a child against the background of an existing tuberculous process is extremely rare. The combination of malignant neoplasm and tuberculosis creates difficulties in differential diagnosis, treatment of diseases, prevention of exacerbations and relapses. This article presents a clinical observation – the development of acute lymphoblastic leukemia (ALL) in a 6-year-old child against the background of TB of the intrathoracic lymph nodes during treatment. TB proceeded favorably despite multiple family contact in the child and resistance of Mycobacterium tuberculosis to anti-tuberculosis drugs in adult relatives of the patient. At the onset of ALL, bilateral pulmonary infiltrates and pleural effusion were observed, which were not associated with TB. Specific polychemotherapy for ALL and continued chemotherapy for TB led to the cure of two diseases. Supportive cytostatic and immunosuppressive therapy for ALL required periodic courses of anti-relapse anti-tuberculosis therapy for 5 years. After 10 years of observation, the child is healthy. Thus, the possibility of a rare in clinical practice combination of TB and ALL in children should be taken into account in the diagnosis and treatment of these diseases. During courses of immunosuppressive therapy for ALL, there is a risk of reactivation of TB. It is necessary to recommend long-term observation of such children by a phthisiatrician and an oncologist to prevent recurrence of both diseases.

The review is devoted to the clinical, biochemical, and molecular genetic characteristics of autosomal recessive mucopolysaccharidoses (MPS) types IV, VI, and VII. MPS IV type, or Morquio’s syndrome, is represented by 2 types – A and B. The cause of the most frequent MPS IVA is hereditary deficiency of galactose-6-sulfatase, due to the presence of inactivating mutations in the GALNS gene. The pathogenetic basis of the disease is associated with excessive accumulation in lysosomes, mainly of cartilage tissue of keratan sulfate and chondroitin-6-sulfate. Main clinical manifestations of MPS IVA are dwarfism and progressive deformity of the spine, sternum, and knees. The milder MPS IVB is due to hereditary β-galactosidase deficiency and is an allelic variant of GM1 gangliosidosis. The cause of MPS VI, or Maroto–Lamy syndrome, and MPS VII, or Sly syndrome, is hereditary deficiency of arylsulfatase B and β-glucuronidase, respectively. The pathogenesis of these diseases is due to the excessive accumulation of dermatan sulfate and, in the second case, additionally, heparan sulfate. Patients with type VI and VII MPS have a Hurler-like phenotype, but in the first case, intellectual deficiency are usually absent, while in Sly syndrome, moderate mental retardation is observed. The possibility of neonatal screening and early diagnosis of these MPS in order to increase the effectiveness of their prevention and treatment is discussed. The importance of experimental models for studying the molecular basis of the pathogenesis of these severe hereditary diseases and the development of various therapeutic approaches, such as bone marrow transplantation, enzyme replacement therapy and substrate-reducing therapy, is emphasized. Descriptions of clinical cases of MPS IVA and VI types are presented.