Reticular Layer Research Articles

ON THE QUESTION OF THE EFFECT OF REGENERATION STIMULATION DRUGS ON THE RESTORATION OF THE SKIN IN CASE OF INJURY

Background. The study of the reaction of tissue (epidermis and dermis) to the medication of regeneration stimulants (МSR) in injuries is relevant both for the development of wound coatings and treatment regimens for the traumatic process. In this study, special attention is paid to the process of stimulation of stem cells in the hair papilla, which play an important role in the restoration of skin structures. The aim of the study was also to study the morphological changes of the epidermis and dermis in the dynamics of trauma. Materials and methods. To conduct the experiment, experimental groups were formed: a burn model without treatment; a burn model with a МSR preparation (oral administration and wound coating); an experimental group with a linear wound with МSR treatment, an experimental group similar reproduction of a wound without suturing with МSR, a control group similar reproduction of a wound without treatment with suturing, a control group - similar reproduction of the wound without treatment and without suturing. Animals were removed from the experiment by inhalation of ether vapors in accordance with the "Rules for carrying out work using experimental animals" and in accordance with the principles of the Helsinki Declaration of the World Medical Association (Declaration of Helsinki, and approved by the Institutional Review Board). Tissue fragments were taken from the site of thermal trauma and healthy tissue for the preparation of histological preparations. The production of paraffin histological sections with a thickness of 5-7 microns was carried out according to generally accepted standard methods. The sections were stained with hematoxylin and eosin. The photos were taken using the Vision Bio system (Epi 2014) and stained with hematoxylin-eosin, which were examined under x100 magnification. The obtained data were processed using MS Excel and Statgraphics software packages using generally accepted methods of statistics. Results. When reproducing thermal trauma In the control group on day 14, there is no epidermis in part of the visual fields within the studied material, the layers are replaced by connective tissue strands, scar tissue is visualized. The dermis is moderately edematous, with neutrophilic and lymphocytic infiltration is weakly expressed, in the papillary and reticular layer it is evenly represented, there are single apoptotic corpuscles. No areas of hemorrhage were detected, but the blood vessels were dilated. While in the experimental group there are signs of restoration of microcirculation with a large number of vessels and a more pronounced layer of the epidermis. When examining scars after a linear wound, it was found that animals who did not receive therapy have a thin scar, and in animals who received МSR, the consequences of surgical intervention are not visualized. Conclusion. The dynamics of the wound process was studied when using a prototype ointment containing a regeneration complex in the treatment of burn and linear wounds in an experiment. The effectiveness of the regenerative complex of a prototype ointment for the treatment of experimental burn and linear wounds in laboratory animals in comparison with the control group was revealed. It has been established that in the treatment of burn and linear wounds with experimental ointment, the healing period of burn wounds is reduced due to more active formation of the microcirculatory bed and the early onset of epithelization.

Possible mechanisms to improve sleep spindles via closed loop stimulation during slow wave sleep: A computational study.

Sleep spindles are one of the prominent EEG oscillatory rhythms of non-rapid eye movement sleep. In the memory consolidation, these oscillations have an important role in the processes of long-term potentiation and synaptic plasticity. Moreover, the activity (spindle density and/or sigma power) of spindles has a linear association with learning performance in different paradigms. According to the experimental observations, the sleep spindle activity can be improved by closed loop acoustic stimulations (CLAS) which eventually improve memory performance. To examine the effects of CLAS on spindles, we propose a biophysical thalamocortical model for slow oscillations (SOs) and sleep spindles. In addition, closed loop stimulation protocols are applied on a thalamic network. Our model results show that the power of spindles is increased when stimulation cues are applied at the commencing of an SO Down-to-Up-state transition, but that activity gradually decreases when cues are applied with an increased time delay from this SO phase. Conversely, stimulation is not effective when cues are applied during the transition of an Up-to-Down-state. Furthermore, our model suggests that a strong inhibitory input from the reticular (RE) layer to the thalamocortical (TC) layer in the thalamic network shifts leads to an emergence of spindle activity at the Up-to-Down-state transition (rather than at Down-to-Up-state transition), and the spindle frequency is also reduced (8-11 Hz) by thalamic inhibition.

Synthesis, Crystal Structure, Computational Investigation of Vanillin Azine Derivative as Potent Blocker of the N‐Terminal Ras‐Binding Domain (RBD) in Human a‐Raf Kinase

AbstractVanillin is the main component of natural vanilla extract and is responsible for its flavoring properties. Besides its well‐known applications as an additive in food and cosmetics. In this, we have synthesized a new vanillin derivative. Its structure was characterized by IR, MS, NMR and confirmed by single‐crystal X‐ray analysis. The asymmetric unit of the title molecule consists of two independent half molecules, each having crystallographically imposed centrosymmetry. Reticular layers approximately parallel to the bc plane are generated from one molecule through O−H⋅⋅⋅N hydrogen bonds. The layers are linked by the second molecule through O−H⋅⋅⋅O hydrogen bonds to form a 3‐D network structure. We carried out density functional investigations to understand the compound‘s molecular reactivity and chemical stability. Frontier molecular orbital (FMO) analysis, global reactivity, and Fukui parameters were calculated at the B3LYP/6‐31+G(d,p) method. In 20 % to 30 % of human malignancies, RAS genes are activated ontogenetically by point mutations. New strategies to block this oncogenic protein are needed since it has proven difficult to create efficient RAS inhibitors. The above‐titled compound shows better structural activity relationship studies against Ras‐binding domine, based on this molecular docking simulation as well as the drug‐likeness analysis carried out for our newly synthesized compound.

Prenatal and postnatal development of New Zealand white rabbit (Oryctolagus cuniculus) teeth: histological and computed tomography aspects

The study reveals a lack of histomorphogenesis in New Zealand white rabbit teeth. The teeth development was examined through sequential histological segments in 24 rabbits from prenatal ages (E19, E21, E23, E25, and E28), neonates (E30), and postnatal age (1 week and 2 weeks); (three animal specimens at each age stage). Rabbit teeth first appeared at 19 days of prenatal life (E19) as an ectodermal epithelial thickening on each side of the mouth opening. At E21, the bud of upper incisor tooth appeared as an epithelial bud, which composed of many condensed epithelium cells, was simply identified from the larger with less condensed vestibular lamina, and was surrounded by mesenchymal connective tissue while the lower incisor took the cap stage. At (E23), tooth regular construction is formed from enamel, dentine, and pulp cavity. Peg incisor appearance (supplementary and assistant incisors) is visible at the lingual surface of the upper major incisor. Teeth prenatal development went through successive stages like initiation, bud, cap, late bell, maturation, and crown stages. The first initiation phase of tooth formation was seen as ectodermal epithelial cell collection at (E19). Bud stage saw on upper incisor tooth, while in cap structure in lower incisor teeth at (E19). A cap-formed tooth is composed of the enamel organ and fundamentally dense mesenchymal tissue. Enamel organs are segmented into three distinct layers: the external tooth enamel epithelial, the internal tooth enamel epithelial, and finally the stellate reticular layer. The cement layer covered teeth all around on enamel on both the labial and lingual sides while not contacting the dentine on the lateral side, forming enamel space. Teeth develop consistently all through life; they have expanded enamel thickness; they are diphyodont teeth; they have two continuous dentitions; they are deciduous and perpetual, with long crown teeth and an open root.

Histological and immunohistochemical characteristic of the gingival stroma in the portion of the third molars in children of various age.

Aim: To evaluate the state of the gingival stromal elements in the portion of the third molars requiring extraction of these teeth due to orthodontic indications considering the stage of tooth germ formation. Materials and Methods: The surgery to extract third molars due to orthodontic indications was performed on 95 children aged 11 to 18 years. The three groups of observation were isolated according to clinical-radiological signs: І (n=30) - children aged 11-13 years; ІІ (n=35) - children aged 13-16 years, and ІІІ (n=30) - children aged 16-18 years. During surgery, the samples of gums were taken from the adjacent areas for examination. The samples were fixed, dehydrated, paraffinized for further histological processing. Immunohistochemical methods were used according to the protocols supplied by a producer. In particular, by means of immunohistochemical method, Ki-67, CD-34 antigens and vimentin with primary antibodies against them were determined. The primary antibodies were visualized by the polymeric visualization system with diaminobenzidine giving a brown color to the places of location of the antigens examined. The data obtained were statistically processed. Results: The results of the study showed that specific gravity of the vascular bed in the gingival papillary layer of children was the most variable. It ranges from (12,7±0,09) % at the stage of "D" root formation to (54,8±0,17) % at the "H" stage. Lower concentrations of CD-34 antigens and vimentin are found in the endotheliocytes of children aged 13-16 and 16-18 years, compared to the children aged 11-13 years (p<0,05). No changes were found in the specific volume of the blood vessels, CD-34 antigens and vimentin in the reticular gingival layer of children from the groups of observation. Conclusions: Therefore, the conducted histological and immunohistochemical study of the connective gingival tissues in the portion of the third molars in children enables to draw a conclusion that in the process of formation of the root of this tooth a number of changes occur in the gingival stroma. They include an increase of the blood flow volume in the papillary gingival layer on the background of a decreased concentration of CD-34 genes and vimentin, a longer stage of development of the third molar root. The specific volume of the islets of neoangiogenesis of the papillary gingival layer is the largest in children aged 13-16 years.

FEATURES OF WOOL QUALITIES AND FORMATION OF SKIN COVER OF YOUNG SHEEP OF THE SOUTH KAZAKH MERINO BREED IN ZHAMBYL REGION CONDITIONS

Until 2030, 17 key areas were selected, the implementation of which could potentially lead the country to the sustainable development of all major spheres of life and the solution of global problems affecting every person in this world. The article reflects and presents scientific research data, objective characteristics of wool qualities and age-related changes signs of the structure of the skin of young South Kazakh merino sheep, as well as studies of the morphological parameters of the skin tissue in the age aspect (from birth to 18 months), and an analysis of their connection with the commercial properties and quality of the semi-finished product obtained from sheep of this breed is given. Productive qualities were studied in a flock of sheep of the South Kazakh Merino breed in “Batay-Shu” LLP. Sheep have a high live weight, shearing and yield of pure wool; rams have a fairly high live weight for the breed; component depending on age from 100-106 kg, and high wool productivity both in physical weight and in washed fiber - 10.3-6.6 kg, with an average output of washed wool of 64.5% thickness, with corresponding development epidermis (0.97-1.3% of the total skin thickness), a well-developed pilar layer (up to 67.7% of the total skin thickness) and relatively weak development of the reticular layer (about 33% of the total skin thickness). The density of hair follicles per 1 mm2 at 18 months of age is 52-60 units, and the secondary follicles/ primary follicles ratio is 12.17-12.77. After weaning and up to 7.5 months, buck lambs experience a noticeable increase in skin within 200 μm. During the same period, a slight increase in skin tissue occurs in ewe hoggs.

Histological anatomical levels of penile shaft. A histochemical evaluation of 15 cases

Abstract Introduction/Objective Penile carcinomas (PeCa) arising in the skin of the shaft are rare. Staging systems for PeCa are based on tumor invasion of anatomical levels designed for tumors arising in the glans and foreskin but not for those primary of the shaft. There is scant information about anatomical levels in the shaft. The objective of this study was to evaluate and describe anatomical levels of the shaft with emphasis of the fascias, using histochemical stains. Methods/Case Report Sections of penile mid shaft from 15 penectomies with PeCa from 2000-2015 were evaluated. H&amp;E, trichromic and orcein stains were performed to evaluate and describe anatomical levels of the shaft. Results (if a Case Study enter NA) Skin: Epidermis: 7-15 cell thick, thin keratin, granulosis, basal pigmentation. Papillary dermis: Loose connective tissue, capillaries, nerve fibers pilo-sebaceous structures. Absence of elastic fibers. Reticular dermis. prominent elastic fibers layer parallel to epidermis merging with dartos. Dartos (superficial fascia): Poorly delineated, merging with reticular layer with no separating space, composed of thin smooth muscle bundles. Deep fascia (Busck's fascia): All tissues between dartos and tunica albuginea. Fibro-elastic, encases vessels, nerves and fibro adipose tissues. Closely attached to the albuginea.Tunica albuginea: Dense mostly fibrous tissue with few elastic fibers encasing corpora cavernosa. Corpus cavernosum: Thick-walled inter-anastomosed vessels. Smaller nutritional vessels, nerves and adipose tissue. No elastic fibers present. Conclusion There are 5 distinct anatomical layers in the shaft. Reticular dermis and dartos should be considered as one layer given the poor delineation between them. This knowledge is necessary for staging and prognosis of the rare PeCa arising in the shaft.

An absence of imperfections: A proposed framework for defining, assessing, and achieving skin glow.

Skin glow is a subcomponent of skin quality. It has become entrenched in the cosmeceuticals and aesthetics lexicons as a synonym for health and youth, but is not well-defined as a scientific metric. To examine the concept of skin glow and determine if it is an objective concept that can be defined and quantified. Literature review was used to develop a survey on current concepts relating to skin quality. The survey results were analyzed descriptively and presented to a focus group comprising five dermatologists and four aesthetic physicians. This group then discussed the concept of skin glow, how to define it and what metrics could be used to assess it. Surveyed practitioners (n = 38) ranked skin quality as the fourth most important factor related to a person's overall aesthetic first impression. Almost all (95%) respondents reported routinely assessing skin quality, citing serial photography (83%), and visual inspection (67%) as the main means of achieving this. The focus group defined skin glow as even reflectance from an unaffected papillary and reticular dermal collagen layer, which is created only when skin does not exhibit any characteristics that detract from this even reflectance. Due to its complexity, the focus group proposed a hierarchal framework for assessment, encompassing patient self-rating, practitioner severity rating, and supplemental use of validated measurement devices. Skin glow can be defined and quantified. More work is warranted to develop a practical skin glow assessment tool suitable for use in the clinic setting.

Features of morphology of the skin of the root of the tail of cattle of different age groups as a suspected factor in the incidence of chorioptosis

Relevance. In the literature, when describing the clinical signs of chorioptotic invasion of cattle, it is indicated that this is a widespread chronic invasive disease of adult livestock. However, it was not possible to find data in the literature on the causes of morbidity of adult livestock. The purpose of our study was to conduct comparative histological studies of the skin of the tail root area in cattle of different age groups.Methods. The research was carried out on cattle in the livestock area of the Gatchina municipal district of the Leningrad region. For histological studies, the skin of the tail root area was taken from clinically healthy animals of a black-andwhite Holstein breed: bulls aged 1 year and adult dairy cows aged 5.5 years. By microscopic analysis of the manufactured preparations, the general histological structure of the skin of animals of different age groups, the morphology of its individual layers in a comparative aspect were studied.Results. It was found that the mesh layer of the dermis is more developed in adult animals than in young ones. Collagen fibers in dairy cows have the greatest thickness compared to young animals, they fit tightly together, the ligature loops lie thickly, forming a diamond-shaped ligature. Histological examination showed an insignificant number of cells in the reticular layer of the dermis in adult animals. In young animals, collagen bundles of the mesh layer of the dermis have a less dense ligature, there are more rare, stretched and not completely finished diamond-shaped structures. In some cases, the bends of the collagen bundles are so rare that the diamond-shaped figures are invisible. But the number of cellular elements in young animals, unlike adults, is increased.It can be assumed that the morbidity of adult animals is explained by the peculiarities of the structure of the dermis, in particular its richer collagen fibers of the mesh layer, since such a denser structure of the mesh layer of the dermis is a good "foundation and foundation" for the cellular the layer where the blood vessels are located to nourish the cells of the epidermis.For more fundamental conclusions, we will continue deeper morphometric studies with the counting of cellular elements in the layers of the epidermis and the measurement of the layers of the dermis.

Dynamics of morphological changes in the cellular layers of retina in the long-term experimental opioid exposure

Relevance of research. There is enough information in the foreign and domestic specialized literature on the issue of morphological reorganization of cells and tissues during experimental opioid exposure and other types of toxic effects on the body today. At present, the issue of structural reorganization in the layers of the retina and disruption of its blood supply processes during subchronic and chronic periods of experimental opioid exposure remains unclear. That is why we decided to supplement, expand and deepen information about these processes by conducting our own research in this direction. The purpose of the study is to clarify the dynamics of pathomorphological changes in the layers of the retina and the links of its hemomicrocirculatory channel in the long term of experimental opioid exposure.Material and methods. The research material was sexually mature, outbred, white male rats, 56 animals in number, weighing 160-270 g, aged 4.5-7.5 months. The initial dose of nalbuphine during the first 2 weeks was 0.212 mg/kg, the next 2 weeks (III-IV weeks) – 0.225 mg/kg, the next (V-VI weeks) – 0.252 mg/kg, the next (VI-VIII weeks ) – 0.260 mg/kg, the next (VIII – X weeks) – 0.283 mg/kg, the next (X – XII weeks) – 0.3 mg/kg, and during (XII – XIV weeks) – 0.45 mg/ kg. Before taking the material of the experimental site, the animal was removed from the experiment with the help of diethyl ether. Rat eyeballs were used as a material for ultrastructural research, considering the preservation of the topographic ratio of the eye membranes. Ultrastructural preparations were prepared according to the generally accepted method. Research results. At the end of the eighth week and the tenth week, persistent hyperemia of the choroidal vessels, degenerative and necrotic changes in the cells of the pigment layer, degeneration of the outer segments of photoreceptors, shortening and fragmentation of mitochondrial cristae of the inner segments of photoreceptors, necrotic changes in the nuclei of individual photoreceptors, degeneration of axons of the outer and inner reticular layers, as well as degenerative and necrotic changes of bipolar and amacrine cells, hypertrophy of processes of Müller cells, degeneration of ganglion cells, hyperemia and perivascular edema of vessels of the outer and inner reticular layers were revealed. After twelve and fourteen weeks, the initial stages of development with subsequent progression of sclerotic changes of Bruchʹs membrane were first detected. The phenomena of degenerative and necrotic changes in the cells of the pigment layer, destruction of the membrane of the outer segments of photoreceptors, degenerative changes in the axons of the outer and inner reticular layers and the layer of nerve fibers, degenerative and necrotic changes in bipolar and amacrine cells, hypertrophic changes in processes of Muller cells, hyperemia and stasis gradually increased, perivascular swellings in the vessels of the inner reticular layer, ganglionic layer and layer of nerve fibers, reactive changes in Muller cells and protoplasmic astrocytes. Conclusion. In the long-term course of experimental opioid exposure, irreversible pathomorphological changes occurred and subsequently progressed, which were caused by an increase in dyscirculatory manifestations in the superficial and deep vascular networks of the retina, causing the deepening of edema phenomena with further compression and hypoxia in the thickness of the retinal layers.

Morphological, anatomical and histological studies on knob and beak characters of six goose breeds from China.

The knob serves as both a sexual indicator of a goose's maturity and a significant packaging attribute that garners consumer attention. However, studies regarding the morphological, anatomical and histological traits of different breeds and ages on the on knob in goose are lacking. In this study, six breeds with typical goose knob types were selected, and their knob size, morphological, anatomical and histological traits were characterized. The results showed that: Knob was more prominent in gander than in female goose, and the difference was the most obvious in Magang goose. Wanxi white goose and Shitou goose had the largest knob bulge, while Magang goose and Sichuan white goose were smaller. The total knob volume of Wanxi White goose and Shitou goose was significantly higher than that of other breeds, regardless of male or female (p < 0.05). The beak volume of Wanxi White goose and gander was significantly higher than that of other goose breeds (p < 0.05). Furthermore, the observation revealed that the "knob" primarily consisted of skin-derived tissue and bony protrusions. As age advances, the knob of both male and female geese undergoes synchronous development, with the knob of male geese typically surpassing that of their female counterparts during the same period. The growth rate of knob in male goose was the fastest from 70 to 120days of age, and slowed down from 300 to 500days of age. The growth rate of knob in female goose was slower than that in male goose. There were essential differences in the composition of Yangzhou goose knob and Magang goose knob. The subcutaneous tissue of Magang goose was rich, and the thickness of epidermis, dermis and various layers was significantly smaller than that of Yangzhou goose (p < 0.05). With the growth of goose knob, the cells of the epidermal spinous layer became denser and gradually condensed into an overall structure, and there was a clear boundary between the dermis and epidermis after adult. In adulthood, the fiber fascicle network was staggered and dense, with greater toughness and elasticity, and the stratum corneum, epidermis, reticular layer, dermis and other skin structural layers became thicker.

Histological indicators of sheep skin of different directions of productivity

The purpose of the research was to study the histological indicators of sheep skin of different directions of productivity and to identify the effectiveness of using sheep of foreign breeds on the breeding stock of domestic fine-wooled sheep of the meat-wool direction of productivity. An analysis of histological indicators of sheep skin in diff erent areas of productivity, including the histostructure of the skin of sheep breeds of foreign selection such as Poll Dorset, Charolais and Ile de France, sheep breeds of domestic selection Stavropol, Manych merino and Dzhalginsky merino has been presented in the article. The study of the mechanism of growth and development of wool fi bers is one of the main tasks of increasing the quantity and improving the quality of wool. In studying the morphology of the skin, it is important to establish the breed and age features of the structure of the root, glandular systems, collagen structures that ensure the quality of sheep skin and wool fi bers. Thus, in sheep of Poll Dorset breed the total skin thickness was 10,3 and 3,6 % higher than in Charolais and Ile-de-France animals, respectively. At the same time, the thickness of the epidermis was almost 1,0 % of the total thickness of the skin, while the pilar layer averaged 61,8 %, the reticular layer 37,23 %, which is consistent with the breed parameters. The biggest density of follicles was observed in sheep of Ile-de-France and Charolais breeds. The superiority over animals of Poll Dorset breed was 17,5 and 10,0 %, respectively. By the ratio of secondary follicles/primary follicles animals of Poll Dorset and Ile-de-France breeds had superiority over Charolais breed by an average of 12,4 and 11,2 %. Sheep of domestic selection had an advantage in skin thickness in animals of Manych merino breed. They surpassed their herdmates of Stavropol breed by 5,2 % and Dzhalginsky merino breed by 11,2 %. In terms of the total density of follicles, animals of Stavropol breed had a slight advantage. The animals of Manych merino breed were 3,2 % inferior to them and Dzhalginsky merino by 1,4 %. There was no diff erence between the breeds by the ratio of secondary follicles/primary follicles.

Histological and immunohistochemical changes in equine sarcoids

The article presents the results of histopathological and immunohistochemical studies of three types of equine skin neoplasms, classified as type 2 fibroblastic sarcoid based on their morphological features. The tumours were localized in the abdominal area, macroscopically presented as dense, fleshy formations without a stalk, yet with small ulcers on the surface. Infection of horses could have occurred through direct or indirect contact with other infected horses and cattle, as well as through insects. Histological examination of the sarcoid established that the epidermis was in a state of hyperkeratosis and acanthosis, with the formation of numerous projections that penetrated deeply into the dermis. The boundaries between the papillary and reticular layers of the dermis were not visualized; the defining feature was the chaotic spindle-shaped fibroblasts that formed a significant number of dense whirl-like structures, or moire patterns, which encircled vessels of a varying caliber. The cell nuclei were predominantly round-shaped and hyperchromatic. Present were both typical and atypical mitotic figures. Replacement of loose connective tissue with collagen fibers was observed intradermally. Upon studying the morphological structure of the sarcoid on semi-thin sections, significant vascularization was observed. Spindle-shaped fibrocytes with branched processes and elongated nuclei were located around vessels of varying sizes, exhibiting well-differentiated single or double nuclei. Fibroblasts of various shapes and sizes with round nuclei were randomly distributed throughout the entire area of the neoplasm. The bulk of the sarcoid consisted of collagen fibers, which turned pink when exposed to methylene blue and further exposure to acid fuchsin. Immunohistochemical studies revealed intense vimentin-positive expression in the sarcoid cells, confirming the hypothesis of their mesodermal origin. Upon detecting Ki-67 antibodies in the sarcoids from three clinical cases, a significant number of cells in the G1 and S phases of mitosis were discovered; the cell nuclei and karyoplasm were stained brown. These actively proliferating cells of the neoplasm constitute the "growth fraction" of the tumour and point to a high risk of recurrence and malignancy.

Morphogenesis of Changes in the Structural Components of the Skin in Cancer Patients with COVID-19 in Older Age Groups

Background: Immunosuppression caused by cancer or cytotoxic drugs, aging, and comorbidities makes cancer patients not only more susceptible to COVID-19, but also more likely to progress to a severe form and increase the incidence of serious complications. The epitheliotropy of this virus is of interest to the study of skin changes and the degree of their manifestation in patients with malignant neoplasms. In this regard, the aim of our research was to study the morphogenesis of changes in the structural components of the skin in cancer patients with COVID-19. Methods and Results: We examined the features of morpho-functional changes in skin components in 80 cancer patients who died in Kursk and the Kursk region for the period January 2021–February 2022. Group 1 included cancer patients with no history of COVID-19, whose cause of death was peritonitis due to colorectal cancer; Group 2 included cancer patients whose cause of death was viral pneumonia caused by COVID-19. Each group was further divided by sex and age. The research material was skin fragments. The results of histological and morphometric studies of the skin show that lymphocytic infiltration was typical for all age subgroups of cancer patients with COVID-19, which had higher numbers of lymphocytes per 100 cells than cancer patients without COVID-19. Infiltrative-inflammatory changes are observed in the skin, the severity of which depends on the patient's age. For the age subgroup of 76-85 years without COVID-19, a more pronounced increase in the ratio of the reticular layer to the papillary layer was characteristic, due to a decrease in the thickness of the papillary layer. Pronounced thickening of the papillary layer was found in all age subgroups of cancer patients with COVID-19, compared with the same age subgroups in cancer patients without COVID-19. Conclusion: It is possible to predict more frequent skin manifestations in cancer patients who have had a new COVID-19 infection, the mechanism of which is mainly due to changes in specific leukocytes, T-lymphocytes, and macrophages and their infiltration of skin tissues.

Seasonal changes in the scrotal skin histology in relation to thermoregulation and testosterone level in camel and buffalo bull.

This study was conducted to compare the scrotal skin dynamics of camel and buffalo bulls regarding thermoregulation, season and testosterone. Scrotal skin and blood samples (n = 8 each) were collected during breeding (October to March) and non-breeding seasons (April to August). Tissue slides were prepared by the paraffin embedding technique followed by hematoxylin and eosin (H&E) staining and were analysed by ImageJ®. Relative humidity and temperature were recorded in different seasons to calculate the thermal humidity index (THI). Serum testosterone level was estimated through radioimmunoassay (RIA). The data were analysed by applying ANOVA, the THS test was used as a post-ANOVA interface and the correlation coefficient was also calculated among season, testosterone and skin parameters. The results showed that skin thickness, season and THI were negatively correlated with testosterone levels. In the neck, body and apex, the papillary layer was thicker in buffalo bull compared to camel bull during the breeding season; however, the reticular layer followed a reverse trend in the apex when THI was low. In the scrotal neck during the non-breeding season, hair follicle (HF) length and density were recorded high in camel bull compared to buffalo bull when THI was elevated. The density of HF followed the otherwise trend in the apex during the breeding season. The density of SG was found highest in all regions of camel bull as compared to buffalo bull and showed direct relation with THI. To conclude, this study delineates how the histo-dynamics of scrotal skin varies and accommodate itself with testosterone and THI over the different season in camel and buffalo.

MICROSCOPIC CHANGES IN RAT’S GINGIVA UNDER CONDITIONS OF EXPERIMENTAL PERIODONTITIS AND THE USE OF MESENCHYMAL STEM CELLS

MICROSCOPIC CHANGES IN RAT’S GINGIVA UNDER CONDITIONS OF EXPERIMENTAL PERIODONTITIS AND THE USE OF MESENCHYMAL STEM CELLS

Pathomorphology of cutaneous mastocytosis

Introduction. Mastocytosis as a result of mast cell infiltration of the skin and other organs develops at any age. The relevance of this work is determined by the lack of systematic data on the pathomorphological features of the clinical forms and types of cutaneous mastocytosis, defined by the Consensus European-American Mastocytosis Group and the WHO classification in 2016. The variability of dermatological clinical manifestations in children and adults, the difficulties in interpreting laboratory tests create a problem for verifying the diagnosis and further treatment. The aim. To determine the main pathohistological features of clinical forms and types of cutaneous mastocytosis. Material and methods. The article includes data from patients who were treated and monitored at the Moscow Scientific and Practical Center of Dermatovenereology and Cosmetology in 2019–2022. Results. The literature and own data on the characteristic pathomorphological patterns that are important for the diagnosis of mastocytosis with skin lesions in children and adults are systematized. The pathological substrate of lesions in diffuse cutaneous mastocytosis and mastocytoma was a massive infiltrate of mast cells in the papillary and reticular layers of the dermis. The histological picture in the monomorphic type of maculopapular cutaneous mastocytosis (MPCM) in children was characterized by a relatively lower density of mast cell infiltration of the papillary dermis compared to other clinical forms of mastocytosis. Also, in children, the density of mast cells in the affected skin was significantly higher compared to adults. In addition, in adults with PPCM, the papillary dermis was less infiltrated with mast cells. This confirms the opinion that the monomorphic type of MPCM in children is phenotypically similar to MPCM in adults. Conclusions. Further prospective follow-up of patients may allow conclusions to be drawn about the prognostic value of pathological examination in mastocytosis in adults and children.

Simplified anterior transpetrosal approach without superior petrosal sinus and tentorial incision for lesions centered in Meckel's cave.

The anterior transpetrosal approach (ATPA) is an effective method to reach lesions in the petroclival region. This approach involves many steps, including superior petrosal sinus (SPS) ligation and tentorial cutting. It is sometimes unnecessary to perform all procedures in the ATPA for certain lesions, especially those centered in the Meckel's cave. Here, we present a simplified anterior transpetrosal approach (SATPA) without superior petrosal sinus and tentorial incision for lesions centered in the Meckel's cave as a modified ATPA. This study included 13 patients treated with SATPA. The initial steps of SATPA are similar to ATPA, excluding a middle cranial fossa dural incision, SPS dissection, or tentorial incision. Histological examination was performed to understand the membrane structure of the trigeminal nerve, which runs through the Meckel's cave. Pathology revealed trigeminal schwannoma (n=11), extraventricular central neurocytoma (n=1), and a metastatic tumor (n=1). The average tumor size was 2.4 cm. The total removal rate was 76.9% (10/13). Permanent complications included trigeminal neuropathy in four cases and cerebrospinal fluid leakage in one case. Histological examination revealed the trigeminal nerve traverses the subarachnoid space from the posterior fossa subdural space to the Meckel's cave and is covered with the epineurium in the inner reticular layer. We used SATPA for lesions located in the Meckel's cave identified using histological examination. This approach may be considered for small- to medium-sized lesions centered in the Meckel space. None.

Effect of Bone Cement Thickness on the Risk of Scalded Skin in Joint Surgery

Bone cement releases a large amount of heat as it polymerizes. Skin burns caused by discarded bone cement are not well understood during arthroplasty. It is important to study the correlates and mechanisms of scalding and to accurately evaluate the severity of burns to guide treatment decisions. Standardized burns were created in eight anesthetized rabbits using different thicknesses of bone cement. Bone cement was uniformly stirred to make thicknesses of 1 mm, 4 mm, 8 mm, 12 mm, 16 mm, and 20 mm and a 20 × 40 mm cuboid. Bone cement samples were then placed on the back of a rabbit, and the temperature changes were recorded with an industrial digital thermometer. One hour later, the appearance of scalded skin was observed, and the rabbits were euthanized. The scalded parts were cut to make pathological sections and stained with HE, and the differences in the depth of the scalded skin caused by different thicknesses of bone cement were observed under a light microscope. Damage caused by 1 mm-, 4 mm-, 8 mm-, 12 mm-, 16 mm-, and 20 mm-thick bone cement samples mainly involved the epidermis, the papillary dermis, the reticular dermis layer, and the full thickness of the skin and the subcutaneous tissue. The maximum temperature of 1 mm, 4 mm, 8 mm, and 12 mm bone cementation had a statistically significant difference (p < 0.001), while there was no significant difference between 12 mm, 16 mm, and 20 mm samples (p=0.856). The time to severe scalding with bone cement at temperatures above 70°C was significantly different between different thicknesses (p < 0.001). The heat released by different thicknesses of bone cement leads to different maximum temperatures and the duration of severe burns, resulting in different degrees of skin burns. Attention should be paid to discarded bone cement to prevent this potential complication in knee arthroplasty.

Histological and histomorphometric study of human palatal mucosa: Implications for connective tissue graft harvesting.

To analyse the histological structure and histomorphometric characteristics of human hard palatal mucosa in order to determine the donor site of choice for connective tissue grafts from a histological point of view. Palatal mucosa samples from six cadaver heads were harvested at four sites: incisal, premolar, molar and tuberosity. Histological and immunohistochemical techniques were performed, as was histomorphometric analysis. In the current study, we found that the density and size of cells were higher in the superficial papillary layer, whereas the thickness of the collagen bundles increased in the reticular layer. Excluding the epithelium, the mean percentage of lamina propria (LP) and submucosa (SM) was 37% and 63%, respectively (p < .001). LP thickness showed similar values in the incisal, premolar and molar regions, and a significantly greater thickness in tuberosity (p < .001). The thickness of SM increased from incisal to premolar and molar, disappearing in the tuberosity (p < .001). As dense connective tissue of LP is the tissue of choice for connective tissue grafts, the best donor site from a histological point of view is tuberosity because it is composed only of a thick LP without the presence of a loose submucosal layer.