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Many problems of modern forest ecology require analysis of the conjugated dynamics of processes occurring at different spatio-temporal scales of the functioning of plant communities and soils resulted from their interaction under the influence of all edaphic and anthropogenic factors. Mathematical models can be an effective tool for such analysis. The aim of this study is to present the implementation of new model system that makes it possible to reproduce in simulation experiments the spatial structure of forest phytocenoses formed by tree and grass-shrub layers, as well as associated heterogeneity of soil conditions and the diversity of ecological niches at different hierarchical levels. To determine the required level of detail of the spatial heterogeneity of forest biogeocenoses related to the processes of their multi-scale functioning, experimental studies were carried out on permanent sampling plots in the Prioksko-Terrasny State Natural Biosphere Reserve and in the «Kaluzhskie Zaseki» State Nature Reserve. The spatial structure of communities and related heterogeneity of ecological conditions were studied using traditional soil and geobotanical, as well as modern instrumental methods. The obtained data were used to construct the algorithms and to estimate the parameters of different blocks of the new system of models. The implementation of a spatially-explicit process-based system of models has shown its ability to reproduce the dynamics of forest ecosystems, taking into account the species composition and spatial structure of different layers of vegetation and the associated patchiness of soil conditions. Due to a wide range of interrelated ecosystem characteristics implemented in the system of models it is possible to simulate productivity, biological turnover of C and N, and the dynamics of forest ecosystems, taking into account their typical spatial structure at different scales. This improves understanding of ecosystem processes and their contribution to maintaining the sustainable functioning of forests, which can be used for predictive assessments of the efficiency of forest management techniques and in solving other forestry and environmental problems.

In many problems of modern forest ecology, it is necessary to analyze the conjugated dynamics of processes occurring at different spatio-temporal scales of the functioning of plant communities and soils resulted from their interaction under the influence of all edaphic and anthropogenic factors. Mathematical models can be an efficient tool for such analysis. The aim of this study is to present the implementation of a new system of models that makes it possible to reproduce in simulation experiments the spatial structure of forest phytocenoses formed by tree and grass-shrub layers, as well as associated heterogeneity of soil conditions and the diversity of ecological niches at different hierarchical levels. To determine the required level of detail of the spatial heterogeneity of forest biogeocenoses related to the processes of their multi-scale functioning, experimental studies were carried out on permanent sampling plots in the Prioksko-Terrasny State Natural Biosphere Reserve and in the “Kaluzhskie Zaseki” State Nature Reserve. The spatial structure of communities and related heterogeneity of ecological conditions were studied using traditional soil and geobotanical, as well as modern instrumental methods. The obtained data were used to construct the algorithms and to estimate the parameters of different blocks of the new system of models. The implementation of a spatially-explicit process-based system of models has shown its ability to reproduce the dynamics of forest ecosystems, taking into account the species composition and spatial structure of different layers of vegetation and the associated patchiness of soil conditions. Because of a wide range of interrelated ecosystem characteristics implemented in the system of models it is possible to simulate productivity, biological turnover of C and N, and the dynamics of forest ecosystems, taking into account their characteristic spatial structure at different scales. This makes it possible to improve the understanding of ecosystem processes and their contribution to maintaining the sustainable functioning of forests, which can be used for predictive assessments of the efficiency of forest management techniques and in solving other forestry and environmental problems.

The article provides primary data on repeated tree measurements collected during two censuses on a permanent sampling plot (440 m × 200 m) established in the old-growth polydominant broad-leaved forest in the Kaluzhskie Zaseki State Nature Reserve (centre of European Russia). The time span between the inventories was 30 years, and a total of 11 578 individuals of ten tree, one shrub species, and several undefined tree species of three known genera were registered. During the surveys, tree identity, stem diameter at breast height (DBH) of 1.3 m, and life status (alive or dead) were recorded for every tree individual with DBH ≥ 5 cm. Additional attributes were determined for some individuals. Field data were digitised and compiled into the PostgreSQL database. An accurate data quality assessment, validation, and cleaning (with documentation of changes) have been performed before data standardisation according to the Darwin Core standard. Standardised data were published through the GBIF repository. From 1986 to 1988, 9811 individuals were recorded within the initial census, including 3920 Corylus avellana individual shrubs. Corylus avellana shrubs were recorded without measuring DBH. From 2016 to 2018, 7658 stems were recorded in the recensus, including 3090 living trees marked during the initial census, and 1641 other living trees reaching the DBH of at least 5 cm. Corylus avellana was not included in the recensus. Thus, over 30 years, about 65% of living tree individuals have survived, but the total number of living trees has not changed considerably. The mean diameter of shade-intolerant tree species (Quercus robur, Fraxinus excelsior, Populus tremula, and Betula spp.) has increased the most remarkably during 30 years. For these species, the increase in average diameter, along with the decrease in numbers, is associated with the death of young trees, presumably due to low illumination under the canopy. Contrastingly, shade-tolerant tree species (Ulmus glabra, Tilia cordata, Acer platanoides) increased in number, while their mean diameter increased slightly or even decreased, that evidences the successful regeneration of these species under the canopy. These data are relevant for investigating forest ecology questions at spatiotemporal scales as a model of natural succession.

AIM: The aim of the present study was to investigate the immunohistochemical expression of selected collagen types, namely collagen types I and V and procollagen type III in the renal parenchyma and interstitium and in the myocardium of spontaneously hypertensive rats. MATERIAL AND METHODS: For the present study, we used two age groups of 6- and 12-month-old spontaneously hypertensive rats. An immunohistochemical analysis was conducted with monoclonal antibodies against collagen types I and V and procollagen type III. A semi-quantitative analysis of immunostaining intensity was conducted with the Image J software. CONCLUSION: The present study suggests a role of collagen types III and V in hypertensive kidney disease, while also establishing the role of increased expression of collagen types I and V in adverse myocardial remodeling (Tab. 1, Fig. 2, Ref. 48). Text in PDF www.elis.sk. [ABSTRACT FROM AUTHOR]

Diabetic kidney disease (DKD) is a leading cause of chronic kidney disease (CKD) and end-stage renal disease worldwide, affecting approximately 40% of individuals with type 2 diabetes (T2DM) and 30% of those with type 1 diabetes (T1DM). As the prevalence of diabetes continues to rise, the burden of DKD is expected to grow correspondingly. This review explores the roles of key molecular pathways, including the apelinergic system, vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) axis, and nitric oxide (NO)/nitric oxide synthase (NOS) signaling, in DKD pathogenesis and potential therapeutic applications. The apelinergic system, involving apelin and its receptor (APLNR), influences endothelial function, glucose metabolism, and renal health. Preclinical studies highlight its dual role in renal protection and injury through anti-inflammatory and antioxidant pathways, while other evidence suggests that it may exacerbate DKD through podocyte damage and angiogenesis. Similarly, the VEGF/VEGFR axis demonstrates a complex contribution to DKD, where VEGF-A promotes pathological angiogenesis and glomerular damage, but its inhibition requires careful modulation to prevent adverse effects. The NO/NOS system, integral to vascular and renal homeostasis, also exhibits altered activity in DKD, with reduced bioavailability linked to oxidative stress and inflammation. This review underscores the intricate interplay between these pathways in DKD, revealing both challenges and opportunities in their therapeutic targeting. Further research is essential to refine strategies and develop effective interventions for DKD management.

Multiple sclerosis (MS) is a chronic neurodegenerative disorder involving demyelination. The cuprizone model is commonly used to study MS by inducing oligodendrocyte stress and demyelination. The subventricular zone (SVZ) plays a key role in neurogenesis, while the neuronal/glial antigen 2 (NG2) is a marker for immature glial cells, involved in oligodendrocyte differentiation. The apelin receptor (APLNR) is linked to neurogenesis and behavior modulation. This study explores the role of APLNR in NG2-positive cells during de- and remyelination phases in the experimental cuprizone mouse model. Thirty male C57BL/6 mice were divided into control (not treated), demyelination (5 weeks cuprizone administration), and remyelination (5 weeks cuprizone administration + 5 weeks recovery) groups. Histological examinations, immunohistochemistry, and immunofluorescence on serial coronal sections were conducted to evaluate corpus callosum (CC) morphology and APLNR and NG2 expression in the SVZ, in addition to behavioral assessments. The histological analysis showed a significant reduction in the CC's thickness and area after five weeks of cuprizone exposure, followed by recovery five weeks post-exposure. During the demyelination phase, APLNR-expressing cells peaked while NG2-positive cells decreased. In the remyelination phase, APLNR-expressing cells declined, and NG2-positive cells increased. Confocal microscopy confirmed the co-localization of NG2 and APLNR markers. Statistically significant differences were observed across experimental groups. Correlation analyses highlighted associations between APLNR/NG2 cell counts and CC changes. Behavioral tests revealed impaired motor coordination and memory during demyelination, with gradual recovery during remyelination. Significant changes in the CC structure and the number of APLNR and NG2-positive cells were observed during de- and remyelination, suggesting that NG2-positive cells expressing APLNR may play a key role in remyelination.

Angiogenesis, the natural mechanism by which fresh blood vessels develop from preexisting ones, is altered in arterial hypertension (AH), impacting renal function. Studies have shown that hypertension-induced renal damage involves changes in capillary density (CD), indicating alterations in vascularization. We aimed to elucidate the role of the apelin receptor (APLNR), neuronal nitric oxide synthase (nNOS), and vascular endothelial growth factor (VEGF) in hypertension-induced renal damage. We used two groups of spontaneously hypertensive rats aged 6 and 12 months, representing different stages of AH, and compared them to age-matched normotensive controls. The kidney tissue samples were prepared through a well-established protocol. All data analysis was conducted with a dedicated software program. APLNR was localized in tubular epithelial cells and the endothelial cells of the glomeruli, with higher expression in older SHRs. The localization of nNOS and VEGF was similar. The expression of APLNR and nNOS increased with AH progression, while VEGF levels decreased. CD was lower in young SHRs compared to controls and decreased significantly in older SHRs in comparison to age-matched controls. Our statistical analysis revealed significant differences in molecule expression between age groups and varying correlations between the expression of the three molecules and CD.

Age-related morphological and physiological changes occur in cells, tissues and organs with high metabolic or mitotic activity; these changes decrease their regenerative capacity. One such change is interstitial fibrosis. Mast cells contain basic fibroblast growth factor and have been related to pro-fibrotic activity. We investigated the role of mast cells in physiological aging of the heart and kidney. We analyzed changes in mast cell number and compared the left and right heart ventricles and kidneys of 6- and 12-month-old Wistar rats. We also evaluated the immunohistochemical expression of basic fibroblast growth factor. Finally, we analyzed changes in the extent of interstitial fibrosis and in the glomerular sclerosis index as nonspecific markers of aging and correlated these parameters with of mast cells. Mast cells were visualized by toluidine blue staining and specific immunohistochemical expression of tryptase. The expression of basic fibroblast growth factor was assessed semiquantitatively. The extent of interstitial fibrosis was investigated using Mallory's trichrome staining. Glomerular sclerosis was evaluated using periodic acid-Schiff staining. We found that the number of mast cells increased significantly in the older rats. We also found that the number of mast cells was greatest in the left ventricle followed by the right ventricle, then the kidney. The immunoreactivity of basic fibroblast growth factor also increased in older animals. Correlations between the number of mast cells and immunoreactivity of basic fibroblast growth factor, extent of interstitial fibrosis and glomerular sclerosis index demonstrated the association between mast cells and age-related tissue remodeling of the heart and kidney.

Among the local factors for oral candidiasis, the piercing of the tongue is recognized by some authors as a risk factor for the colonization of Candida albicans . There are few case reports in which Candida spp. colonization and infection are associated with tongue piercing but only one microbiological study supports this hypothesis in general. The aim of this study was to examine this possible association between the presence of both tongue piercing and Candida spp. in healthy individuals. Positive results for tongue colonization with Candida spp. were found in four (12.9%) of the tongue-pierced subjects and in three (9.67%) subjects of the control group ( p = 0.550). All samples were identified as Candida albicans . The univariate and logistic regression analyses of possible risk factors for tongue colonization revealed that gender ( p = 0.024), smoking more than 10 cigarettes per day ( p = 0.021), and improper hygiene ( p = 0.028) were statistically significant influencing factors in the multivariate analysis. The results suggest that the piercing of the tongue is not a risk factor for colonization of Candida spp.

Introduction: An increasing number of studies have shed light on the role of cardiac mast cells in the pathogenesis of hypertension-induced myocardial remodeling. Mast cells promote fibroblast activation, myofibroblast differentiation and subsequent collagen accumulation through the action of tryptase, chymase, histamine and fibroblast growth factor-2. The aim of the present study was to report on the changes in the number of mast cells as evaluated through toluidine blue, tryptase and c-kit staining, to assess the extent of interstitial fibrosis and correlate it with the changes in the number of mast cells and to analyze the immunohistochemical expression of fibroblast growth factor-2 in two groups of spontaneously hypertensive rats indicative of established and advanced hypertensive heart disease. A novel aspect of our work was the analysis of all parameters in the right ventricle., Material and Methods: For the present study, we used 6- and 12-month-old spontaneously hypertensive rats. A light microscopic study was conducted on sections stained with hematoxylin and eosin and toluidine blue. For the immunohistochemical study we used monoclonal antibodies against mast cell tryptase and fibroblast growth factor-2 and a polyclonal antibody against c-kit. The expression of fibroblast growth factor-2 was assessed semi-quantitatively through ImageJ. The number of mast cells was evaluated on toluidine blue-, tryptase- and c-kit-stained sections and a comparative statistical analysis with the Mann-Whitney test was conducted between the two age groups. A separate statistical analysis between results obtained through immunostaining for tryptase and for c-kit was conducted in each age group with the Wilcoxon signed-rank test. The extent of fibrosis was assessed quantitatively on slides stained with Mallory's trichrome stain as a percentage of the whole tissue and compared between the two age groups. Spearman's correlation was used to test whether a correlation exists between the number of mast cells and the percentage of interstitial fibrosis., Results: Mast cells with typical cytoplasmic granules were visualized in the interstitial tissue and in the perivascular zone in both age groups. In both ventricles, their number increased significantly in 12-month-old animals as evaluated through all three staining methods. Moreover, immunostaining for tryptase and for c-kit yielded comparable results. The immunoreactivity of fibroblast growth factor-2 increased in both ventricles in older animals. Expression of this protein was particularly intensive in the cytoplasm of connective tissue cells with the characteristic features of mast cells mainly found in the areas of fibrotic alterations in 12-month-old spontaneously hypertensive rats. In both ventricles, interstitial fibrosis was more extensive throughout the myocardium of older animals and was positively correlated with the changes in the number of mast cells in both age groups., Conclusion: The present study reported for the first time that the increase in the number of mast cells, observed as hypertension-induced myocardial changes progress, is statistically significant and confirmed that this process takes place in both ventricles. This increase is accompanied by a higher expression of fibroblast growth factor-2 and is more strongly correlated with the more pronounced interstitial fibrosis in older animals, further supporting the role of mast cells in the structural changes taking place in the myocardium in response to systemic hypertension., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Hypertension-induced renal injury is a multifactorial process which plays a crucial role in the development of chronic kidney disease. Multiple studies have demonstrated that interstitial rather than glomerular changes correlate better with renal functional capacity. Recent evidence indicates that mast cells and cell signaling proteins such as fibroblast growth factor-2 may contribute to the progression of interstitial changes under hypertensive conditions. The aim of our study was to determine the localization of mast cells in the renal cortex and report on the changes in their number, to analyze the distribution of fibroblast growth factor-2, to assess the extent of renal fibrosis and to evaluate renal damage and correlate it with the changes in the number of mast cells in a model of hypertension-induced renal injury by comparing two age groups of spontaneously hypertensive rats. We used 6- and 12-month-old animals. A light microscopic study was conducted on sections stained with hematoxylin and eosin, periodic acid-Schiff stain, Mallory's trichrome method and toluidine blue. For the immunohistochemical study we used monoclonal antibodies against mast cell tryptase and fibroblast growth factor-2 and a polyclonal antibody against c-kit. The expression of fibroblast growth factor-2 was assessed semi-quantitatively. The number of mast cells was evaluated on toluidine blue-, tryptase- and c-kit-stained sections, as well as double-stained sections and a comparative statistical analysis with the Mann-Whitney test was conducted between the two age groups. Our results showed that mast cells were located mainly in the peritubular and perivascular areas and were absent in the region of the renal corpuscles. Their number increased significantly in 12-month-old animals. Immunostaining for tryptase, c-kit and double staining for both molecules yielded identical results. The immunohistochemical expression of fibroblast growth factor-2 increased in the kidneys of older animals, as did the percentage of collagen fibers. In addition, we described more severe renal damage in 12-month-old spontaneously hypertensive rats and noted a positive correlation in both age groups between the number of mast cells on the one hand and glomerular sclerosis index and tubulointerstitial damage index, on the other. The results obtained in the present study support the pivotal role of mast cells in the development of hypertension-induced kidney damage., Competing Interests: Declarations of Competing Interest None., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

While much is known about the ligament, the precise morphology and function of the thin layer of connective tissue lining its surface, termed the epiligament, have not been fully studied yet. Herein, we aimed at reviewing the recent findings on the structural and functional significance of the epiligament in both animal models and human tissue. The epiligament is made up of various connective tissue cells such as fibroblasts, fibrocytes, mast cells, and adipocytes and contains a number of neurovascular bundles. Arrangement of collagen fibers in the epiligament is rather chaotic, in multiple directions, which allows for greater mobility and resistance to stress. Differences in the collagen content and types of enzymes of the group of matrix metalloproteinases between the epiligament and the underlying ligament tissue have been reported and are reviewed herein. While the ligament tissue mainly contains collagen type I, the epiligament is also rich in collagen types III and V. As suggested by a number of studies, the epiligament plays a key role in ligament repair as a donor of cells and matrix metalloproteinases, particularly matrix metalloproteinase-2 and 9, which are essential for scar tissue remodeling. In conclusion, future studies will likely reveal additional functional aspects of the epiligament, which may allow scientists to devise more suitable treatment strategies for damaged ligaments in a world where injuries resulting from sports activities or daily routine have long merited their due attention., Competing Interests: The authors have declared that no competing interests exist.