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BACKGROUND: Research on the subject of the influence of SARS-CoV-2 mechanisms on human homeostasis remains an actual problem. Particular interest is the study of pathomorphological changes in the appendix in children with COVID-19. OBJECTIVES: Aim of this study: morphological and molecular biological evaluation of the appendix in children of different age groups with COVID-19. METHODS: Groups were formed on the basis of anamnestic, clinical, and morphological data: I (n = 42; aged 2 to 18 years, average age-10.8 ± 4.79)-with an established clinical diagnosis: coronavirus infection (COVID-19; PCR+); II (n = 55; aged 2 to 18 years, average age-9.7 ± 4.77)-with a confirmed clinical diagnosis of acute appendicitis; collected before the onset of the COVID-19 pandemic in 2017-2019; and III (n = 38; aged 2 to 18 years, average age-10.3 ± 4.62)-the control group. Histological and immunohistochemical studies were conducted using primary antibodies to CD3, CD4, CD68, CD163, CD20, and CD138 and to pro-inflammatory (IL-1, IL-6) and anti-inflammatory (IL-4, IL-10) cytokines. RESULTS: In most samples of appendixes in children with COVID-19, signs of destructive phlegmonous-ulcerative and gangrenous appendicitis were discovered. An increase in CD3+, CD4+, CD68+, CD163+, and CD20+ CD138+ immunocompetent cells was found in the appendix of children with COVID-19. As well, there was an increase in pro-inflammatory (IL-1, IL-6) and anti-inflammatory (IL-4, IL-10) cytokines. CONCLUSIONS: The aforementioned pathological and immunohistochemical changes were more pronounced in the group of children aged 6-12 years (childhood).
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Background: At present, the damage of male reproductive function caused by electron irradiation, as well as the development of methods for its correction are the relevant topics for further research. In fact, the effect of leukocyte-poor platelet-rich plasma (LP-PRP) growth factors are poorly investigated on different aspects of male fertility. Methods: In this study, Wistar rats were divided into four groups; I) control which were injected with saline; II and III) groups (n=65) whose testes were locally irradiated with electrons to a dose of 2 Gy (linear accelerator "NOVAC-11"); III) the group (n=30) which received LP-PRP for 11 weeks after irradiation; and IV) animals (n=30) which received only LP-PRP (conditional control). The testes were studied by histological, immunohistochemical (IHC), western blotting, and TUNEL methods using Ki-67, Bcl-2, and p53. Comparison between groups was performed and p<0.01 was set as the level of significance. Results: The results showed a decrease in the expression levels of Ki-67 and Bcl-2 besides an increase in p53-positive cells by the end of the experiment (p<0.01). After injection of LP-PRP, a gradual restoration of the proliferative activity of gametes was noted, which was confirmed by an increase in the proportion of Ki-67- and Bcl-2-positive germ cells (46.4±2.3, p<0.01 and 23.5±1.1, respectively, p<0.01). Conclusion: Ki-67 expression and TUNEL analysis in the testes revealed a modulation of the proliferative-apoptotic balance towards apoptosis of germ cells after 2 Gy local electron irradiation. A tendency to restore the proliferative-apoptotic balance was noted after LP-PRP injections as indicated by increase in Ki-67-positive germ cells.
ABSTRACT
Based on studies that focused on the effect of SARS-CoV-2 on human tissues, not only pulmonary invasion was revealed, but also impaired testicular function. Thus, the study of the mechanisms of influence of SARS-CoV-2 on spermatogenesis is still relevant. Of particular interest is the study of pathomorphological changes in men of different age groups. The purpose of this study was to evaluate immunohistochemical changes in spermatogenesis during SARS-CoV-2 invasion in different age groups. In our study, for the first time, a cohort of COVID-19-positive patients of different age groups was collected, and the following were conducted--confocal microscopy of the testicles and immunohistochemical evaluation of spermatogenesis disorders in SARS-CoV-2 invasion with antibodies to the spike protein, the nucleocapsid protein of the SARS-CoV-2 virus, and angiotensin convertase type 2. An IHC study and confocal microscopy of testicular autopsies from COVID-19-positive patients revealed an increase in the number of S-protein- and nucleocapsid-positively stained spermatogenic cells, which indicates SARS-CoV-2 invasion into them. A correlation was found between the number of ACE2-positive germ cells and the degree of hypospermatogenesis, and in the group of patients with confirmed coronavirus infection older than 45 years, the decrease in spermatogenic function was more pronounced than in the cohort of young people. Thus, our study found a decrease in both spermatogenic and endocrine (Leydig cells) testicular functions in patients with COVID-19 infection. In the elderly, these changes were significantly higher than in the group of young patients.
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Background: Skin cancer is the most frequently diagnosed type of cancer among all malignant neoplasms. The decrease in mitotic activity and the death of intact keratinocytes arise due to the constantly renewing epithelium being highly sensitive to ionizing radiation. Aim: The aim of the study is immunohistochemical evaluation of the proliferative-apoptotic balance of keratinocytes, the fibrous component of the skin, and the expression of pro-inflammatory and anti-inflammatory cytokines after single or fractional local electron irradiation. Methods: Wistar rats (n = 80) were taken from the ITM&B Vivarium (Sechenov University) and divided into groups: I-control, which were injected with saline; and experimental groups, local electron irradiation at doses: II-8 Gy (single), III-40 Gy (single), IV-summary dose 78 Gy (fractional; 13 Gy per day for 6 days). We performed histological analysis, histochemical analysis using Masson, safranine, and picrosirius red staining, immunohistochemical (Ki-67, caspase-3, p53, types I and III collagens, IL-1, IL-6, IL-4, and IL-10) and morphometric analysis of skin fragments of the outer surface of the thigh, irradiated in accordance with the design of the experiment. The early and delayed effects of local electron irradiation at different doses were studied. Results: After local electron irradiation, dose-dependent morphological changes in the skin of the experimental groups were observed: violation of the histoarchitectonics of the skin confirmed by morphological and morphometric analysis, the proliferation of connective tissue according to the results of histochemical and immunohistochemical studies with signs of the radiation-induced skin fibrosis development, an increase in the levels of pro- and anti-inflammatory cytokines. We observed the most pronounced signs of radiation-induced skin damage in the group of fractional irradiation after 3 months. Conclusion: 8 Gy and 40 Gy single local electron irradiation leads to a shift in the proliferative-apoptotic balance of keratinocytes toward their apoptosis, which activity is directly correlated with the dose of ionizing radiation, and 78 Gy in fractions leads to partial desquamation of the epithelium and inflammatory infiltration. In addition, after 3 months a significant increase in the expression of type I and III collagen fibers and the development of radiation-induced skin fibrosis takes place against the background of 78 Gy fractional local electron irradiation.
Subject(s)
Electrons , Animals , Rats , Anti-Inflammatory Agents , Cytokines , Fibrosis , Rats, WistarABSTRACT
BACKGROUND AND PURPOSE: With the emergence of linear accelerators in radiotherapy, it becomes necessary to accurately select new dosing regimens. The purpose of this study was to assess the morphological changes of spermatogenesis after radiation exposure. MATERIALS AND METHODS: Male Wistar rats (n = 40) were subjected to targeted ionizing radiation on a pulsed electron accelerator "NOVAC-11" with doses of 2, 8 and 12 Gy. Spermatogenesis was assessed a week later using light microscopy and immunohistochemical method (antibodies to Ki-67, Bcl-2, p53, Caspase 3). RESULTS: A decrease in the number of normal germ cells was seen in all experimental groups, while radioresistant Sertoli and Leydig cells were barely affected. The most serious damage to the tubules and germ cells was observed in 8 and 12 Gy irradiation groups. IHC analysis of testes after irradiation showed a shift in the proliferative-apoptotic balance toward apoptosis of germ cells: a decrease in the expression levels of Ki-67 and Bcl-2, an increase in p53-positive and caspase 3-positive cells by the end of the experiment. CONCLUSION: Dose-dependent progressive pathomorphological changes in histoarchitectonics of the testes are traced, and a decrease in the number of germ cells is seen on the seventh day after irradiation with a pulsed electron accelerator "NOVAC-11".
ABSTRACT
MATERIALS AND METHODS: Experimental animals (n = 135) were divided into 5 groups: I - control (n = 10); II - 2IR (n = 35; 2 Gy); III - 2IR + LP-PRP + IGF-1 (n = 30); IV - 2IR + LP-PRP (n = 30); V - LP-PRP (n = 30). RESULTS: Electron irradiation reduces the number of germ cells in comparison with the control group. After injection of LP-PRP + rhIGF-1 significantly increased the number of germ cells, Sertoli and Leydig cells, the height of germinal epithelium, area and diameter of seminiferous tubules. CONCLUSION: LP-PRP + rhIGF-1 has a normalizing effect on structural and functional disorders of the testis caused by electron irradiation.
