The article is devoted to the life path and scientific legacy of the outstanding Soviet and Russian anatomist, Academician Mikhail Romanovich Sapin (1925–2015). It examines the unique combination in his biography of a wartime past (participation in the Great Patriotic War, the Battle of Stalingrad) and decades of fruitful work in the field of morphology. The primary focus is on his revolutionary contribution to science – the systemic reinterpretation of the role of lymphoid organs and the creation of a new scientific field: immunomorphology. The article details his pedagogical talent, his long-term leadership of the Department of Human Anatomy at  the  I.M. Sechenov  First  Moscow  State  Medical  University  and the  Laboratory of Functional Anatomy at the  Research Institute of Human Morphology, as well as his role as an organizer of science. The legacy of M.R. Sapin, which unites fundamental discoveries, pedagogical mastery, and the development of museum work, is presented as an integral part of modern medical science and education.

This article is devoted to the life and multifaceted work of the outstanding Russian morphologist, educator, and organizer of medical science, Lev Lvovich Kolesnikov (1940–2018). Using a biographical approach, it highlights the key stages of his professional journey: from his studies at the Moscow Medical-Stomatological Institute and early scientific work on maxillofacial anatomy to his tenure as Head of the Department of Human Anatomy at the Moscow State University of Medicine and Dentistry and President of the All-Russian Scientific Society of Anatomists, Histologists, and Embryologists. Special attention is paid to his major scientific and practical achievements, including the defense of his doctoral dissertation on the anatomy of the esophagogastric junction, the creation of the fundamental monograph “The Sphincter Apparatus of Man”, the establishment of a department of anatomy at Kabul University, and his participation in the forensic examination of the remains of the Russian imperial family. The article emphasizes his leading role in the development of modern  anatomical  terminology  at  the  international  level,  including  the  editing of  the  trilingual publication  “International Anatomical Terminology”. The immense contribution of L. L. Kolesnikov to medical education is noted: the introduction of programmed learning and computer technologies, the creation of unique textbooks, atlases, and an anatomical museum, and the supervision of more than 25 candidate and doctoral dissertations. His scientific legacy, organizational work, and pedagogical talent left an indelible mark on the development of Russian morphology, establishing a strong scientific school and strengthening the professional community of anatomists in Russia.

Immuno-oncology is an actively developing area of applied research that has revolutionized cancer treatment. In particular, NK cells are classified as cytotoxic lymphocytes that play a crucial role in recognizing and eliminating malignant or infected cells. The aim of the study was to perform a histological and immunohistochemical  evaluation  of  human  tumor  xenografts  (human  pancreatic cancer) and internal organs of immunodeficient mice following the administration of a human NK cell suspension. Material and methods. Previously, xenografts were modeled on 4 NBSGW mice by subcutaneous administration of ASPC-1 tumor cells (human pancreatic cancer). On day 24 of the study, the animals were injected with NK cell suspension intravenously in the amount of 8.8 million and 9.2 million to mice №2 and №4, and subcutaneously in the amount of 10 million and 14 million NK cells to mice №1 and №3, respectively. On day 28 of the study, the animals were euthanized and pathomorphologically examined. Routine histological assessment of the internal organs of the mice, immunohistochemistry of xenograft samples for the presence of tumor cells with Cytokeratin 7 and Pan-Cytokeratin antibodies, as well as xenografts and internal organs of mice for the presence of CD56+ cells were performed. Results. The histoarchitecture of organs and tissues in animals was preserved, metastases were found in the lungs, no infiltration of CD56+ cells in this area of the lung tissue was noted. Single weakly positive CD56+ cells were observed in the xenografts, the membrane staining of which was barely visible. In the spleen, CD56+ cells were single, and part of the xenograft and spleen vessels (peripheral nerve fibers, pericytes) were also brightly stained. In the xenograft samples, small-droplet dystrophy of oncocytes, inflammatory infiltration and the cell renewal index were visualized less than or equal to 1.0, which together indicates mild changes in the tumor structure. Conclusion. The therapeutic effect of the NK cell suspension increases tumor pathomorphism, the areas of necrosis increase, while the cell renewal coefficient index decreases, but further studies are needed with an increase in the dose or frequency of administration.

This article is devoted to the study of the dynamics of histological changes in experimental osteomyelitis of the femur in rabbits. The aim of the study is to study the dynamics and nature of morphological changes in bone tissue and bone marrow of the femur at different stages of experimentally induced osteomyelitis in rabbits. Material and methods. The experiment was performed on 18 Soviet Chinchilla rabbits. Osteomyelitis was modeled by intraosseous administration of a suspension of Staphylococcus aureus at a concentration of  1×10⁸ CFU/ml into the distal metaphysis of the femur. The control group of animals received an injection of sterile saline. Animals were withdrawn from the experiment on days 3, 7 and 14. Light microscopy of histological sections stained with hematoxylin and eosin, as well as according to van Gieson, was used for morphological examination. Results. It was established that osteomyelitis develops in stages. On the 3rd day, a picture of acute serous-purulent inflammation of the bone marrow with massive neutrophilic infiltration, vascular thrombosis and initial signs of necrosis of the bone trabeculae was observed. By the 7th day, the inflammation acquired a purulent-destructive character with the formation of abscesses, bone tissue sequesters and periosteal reaction. A sharp increase in the number of osteoclasts was noted. On the 14th day, the process passed into the chronic phase: the formation of a demarcation ridge of coarse-fibrous bone tissue surrounding the sequesters was noted. Active osteogenesis was combined with areas of destruction. Conclusion. The study demonstrates that the experimental model of osteomyelitis induced by the introduction of Staphylococcus aureus into the femur of rabbits reliably reproduces the key pathomorphological stages of the disease characteristic of humans (acute, destructive and chronic). The obtained data allow using this model for further study of osteomyelitis pathogenesis and preclinical evaluation of the effectiveness of new therapeutic methods.

The relevance of this study is determined by the high frequency of patient visits with temporomandibular joint (TMJ) pathologies, which highlights the need for a more detailed study of the anatomical and morphological features of the joint's bony structures and their relationship with the shape of the skull. The aim of the study was to investigate the relationship between the shape of the articular surfaces of the TMJ and the skull type in individuals of the first mature age period. Material and methods. The research material consisted of the results of cone-beam computed tomography scans performed in sagittal and frontal projections on 155 patients aged 21 to 35 years with orthognathic occlusion and physiological occlusion. Results. The study results showed that an oval mandibular fossa was most frequently associated with an oval mandibular condyle: on the right side in 38.1% of cases, and on the left side in 36.8% of cases. With an angular-shaped fossa, an oval condyle also predominated: on the right side in 11% of observations and on the left side in 13%. With a conical fossa on the right side, a conical condyle was more common (6.4%), whereas on the left side with the same fossa shape, a bean-shaped mandibular condyle predominated (11%). For a rounded fossa on the right side, a bean-shaped condyle was most characteristic (10.3%), while on the left side, a conical condyle was most characteristic (7.1%). An oval shape of the mandibular fossa was the most prevalent across all skull types. Bilateral asymmetry in the shape of the mandibular condyle was not statistically confirmed; therefore, the analysis was conducted considering the overall relationship between skull shape and mandibular condyle shape.  Conclusion. The study  confirms the existence of a relationship between the shape of the articular surfaces of the TMJ and the neurocranium. These structural features may be associated with differences in the anatomy and biomechanics of the jaw-facial apparatus among different skull types.

The aim of the study was to evaluate the morphometric parameters and cellular composition of the splenic white and red pulp in rats at 1 and 6 months after a 30-day course of selenium supplementation. Material and methods. The study object was the spleen harvested at 1 and 6 months after the completion of a 30-day oral administration of selenium at a dose of 20 µg/kg of body weight per day. The spleen of intact animals, whose age corresponded to the age of rats in the experimental group, served as the control. Morphometric parameters of the spleen were determined; the Kernohan index and lymphoid coefficient were calculated; and an immunohistochemical assessment of the distribution of CD3+, CD21+, and CD68+ cells was performed. Results. One month after selenium administration, lymphoid nodules (LN) without germinal centers predominated; the LN area and the thickness of the marginal zone were reduced. An increase in the lymphoid coefficient was observed, along with a strong positive correlation between the expansion of the periarterial lymphoid sheath and the number of CD3+ T-lymphocytes, as well as a strong inverse correlation between the number of CD3+  T-lymphocytes and the Kernohan index. In the experimental group at 6 months, a reduction in the severity of involutional processes was observed compared to control animals. An increase in CD3+ T-lymphocyte content was  also  noted  in  all  splenic  structures,  accompanied  by a decrease  in the number of CD21+ and CD68+ cells.  Conclusion. Oral selenium supplementation activates T-lymphocyte differentiation and promotes the migration of macrophages and B-lymphocytes from the spleen to other organs. This process is accompanied by an increase in CD3+ cell count and a decrease in the number of CD68+ and CD21+ cells across its various structures.

The aim of the study was to describe the peculiarities of the ultrastructural organization of the inner sheath of the wall of the ascending part of the aorta of rats born prematurely at 24 h and to compare them with similar structures of rats born at term. Material and methods. The study was performed on male and female Wistar rats, which were divided into 2 groups: control group (premature rats, gestational age 22 days, n=32)  and experimental group  (rats born 24 hours prematurely, gestational age 21 days, n=22). Premature birth Wistar rats one day before the planned time of labor. Animals of control and experimental groups were bred at 1, 2, 4, 8 and 24 weeks of postnatal development by carbon dioxide asphyxia. Fragments of the wall of the ascending part of the aorta of preterm and premature animals were analyzed using a transmission electron microscope (transmission electron microscopy). Results. In prematurely born immature animals degenerative processes in the form of swelling of organelles of synthetic and energetic apparatuses are determined in endotheliocytes of the inner sheath of the aortic wall.  In the later postnatal period of ontogenesis (4-8 weeks) in sexually mature prematurely born rats, Weibel-Pallade's corpuscles, absent in prematurely born rats, are detected. In the late postnatal period of ontogenesis, vacuolization of endotheliocyte cytoplasm and thickening of the subendothelial layer, in which cells with fibroblast-like morphology are detected in prematurely born rats. Thinning and ruptures of the internal elastic membrane of the wall of the ascending part of the aorta of prematurely born rats are detected from the 4th week of the experiment. Conclusion. Premature birth leads to the development of endothelial dysfunction characterized by degenerative processes of endotheliocytes, thickening of the subendothelial layer, and thinning of the internal elastic membrane.

The aim of the study was to compare the electron microscopic and microscopic characteristics of the first two phases of spermiogenesis in seven mammalian species. Material and methods. For electron microscopy, testicular specimens were fixed in 2.5% glutaraldehyde and 1% osmium fixative. Sections were prepared on BS-490 and LKB-4800 ultramicrotomes. Sections were contrasted with uranyl acetate and lead citrate and examined under a Tesla BS-500 electron microscope. Results. During the first Golgi phase, the Golgi apparatus forms an acrosomal vesicle and small granules. During the second cap phase, the small granules in the acrosomal vesicle combine to form a single large granule. The acrosomal vesicle and acrosomal granule spread over the nucleus, forming a cap. In northern fur seals, silver foxes, and minks, indentations in the spermatid nuclei were found at the location of the acrosomal vesicle. In sheep, sea otters, and beavers, indentations in the spermatid nuclei at the vesicle attachment site are absent. Conclusion. During the Golgi phase, the acrosomal vesicle and acrosomal granule form. During the cap phase, the acrosomal structure spreads over the apical surface of the nucleus, forming a cap over the nucleus. In the northern fur seal, fox, and mink, the acrosomal vesicle forms a deep depression in the spermatid nucleus, which is not found in the ram, beaver, and sea otter.

The search for new methods to preserve and exhibit anatomical specimens remains relevant due to the significant need for such material as visual teaching aids and for the advancement of museum collections in university morphology departments. The modern chemical industry, with its novel polymeric materials and tools, offers solutions to overcome the limitations of traditional museum preservation techniques. These advancements enable the creation of anatomical specimens that require no special maintenance after processing, unlike classical conservation methods. A particular challenge lies in exhibiting corrosion casts of hollow organ structures.  Due  to  their inherent fragility and the considerable effort required to produce each specimen, ensur ensuring their long-term preservation is of paramount importance. The aim is to develop a method for creating and preserving gross anatomical specimens that are suitable for safe, daily use in educational settings and for exhibition in scientific museums and morphological collections. Material and methods. The creation of the specimen collection according to our own methods utilized samples from the museum archive of the A.P. Avtsyn Research Institute of Human Morphology of the B.V. Petrovsky Research Center of Surgery and a polymer material – a deep-pour epoxy resin. We employed our own techniques for biomaterial dissection and the creation of corrosion casts, followed by their encapsulation in the polymer medium. Results. Using the techniques we developed, 180 anatomical specimens were produced. The issues and limitations of classical preservation and exhibition methods are also examined. Conclusion. The results of our study clearly demonstrate the potential for applying the proposed methods of processing, dissecting, preserving, analyzing, and exhibiting museum anatomical specimens.

The article, timed to coincide with the anniversary of V.I. Kozlov – Head of the Department of Human Anatomy at the Patrice Lumumba Peoples' Friendship University of Russia, Honored Scientist of the Russian Federation, Academician of the International Academy of Sciences of Higher Education, Doctor of Medical Sciences, Professor – examines his scientific and pedagogical achievements. V.I. Kozlov is the founder of a new direction in morphology: the in vivo study of the structural organization of the microcirculatory bed. He developed the concept of the microvascular module as a structural and functional unit, and made significant contributions to the study of microcirculation under normal and pathological conditions, across different ages, and under laser exposure. For over 50 years, V.I. Kozlov has been engaged in teaching. He is the author and editor of numerous textbooks, study guides, and methodological works for medical universities, which have received prestigious awards. Professor V.I. Kozlov established an original scientific school, under whose guidance dozens of dissertations have been defended. He founded and for many years headed the journal "Laser Medicine," and organized numerous all-Russian and international scientific congresses and conferences. The scientific and educational activities of Valentin Ivanovich have been recognized with the titles of Honored Scientist of the Russian Federation and Honorary Worker of Higher Education. His research has been supported by grants from Russian and international foundations. The vibrant personality of V.I. Kozlov as a renowned scientist, talented educator, and science organizer, whose long and fruitful career serves as a source of inspiration for students and colleagues, is highlighted.

December 2025 marks the 75th anniversary of the famous Russian histologist, teacher, Doctor of Biological Sciences, Professor of the Department of Histology, Cytology and Embryology at Orenburg State Medical University, Honored Worker of the Higher School of the Russian Federation Nikolai Nikolaevich Shevlyuk. He was born on December 10, 1950 in the village of Linovitsk in the Martuk district of the Aktobe region of Kazakhstan in a family of employees of the Shevchenko MTS. N.N. Shevlyuk graduated from the Orenburg Pedagogical Institute (Faculty of Natural Geography, Department of Biology and Chemistry) in 1972. In 1972-1975 — he is a postgraduate student at the Department of Histology at the Orenburg Medical Institute. Since 1975 he has been working at the same department (since 1975 — assistant, since 1990 — associate professor, since 1998 — professor of the department). At the same time, in 1998-2006, he was a senior and then a leading researcher at the Laboratory of Functional Cell Morphology at the Institute of Cellular and Intracellular Symbiosis of the Ural Branch of the Russian Academy of Sciences. In 2000-2017, he worked concurrently as a professor at the Department of Zoology and Ecology of Orenburg State Pedagogical University. The degree of Candidate of Biological Sciences was awarded in  1978, Doctor of  Biological Sciences — in 1998. The academic title of associate professor  was awarded to N. N. Shevlyuk in 1991, professor — in 2000. His scientific research is devoted to the priority areas of modern biology and medicine – comparative and evolutionary histology, cell biology, history of natural sciences, and issues of teaching methods of histology. He is the author of more than 600 scientific and educational works, including 19 monographs. He described for the first time the ultrastructure of the Leydig cells of the testes of a number of vertebrates and identified the main directions of adaptive rearrangements of testicular endocrinocytes under the influence of various stressful influences. As a result of many years of intensive research on the problems of reproduction under the guidance of N.N. A new ecological and morphological scientific field has been founded and is successfully developing at the Department of Histology of the Orenburg Medical University, the object of which is the organs of the reproductive system of vertebrates living in anthropogenically transformed and natural ecosystems of the steppe zone of the Southern Urals.

This article provides an overview of the presentations delivered at the First Spanish National Congress on Innovations in the Teaching of Anatomy, Histology, and Cell Biology, held in the summer of 2025. The event, organized by the Autonomous University of Madrid, showcased a wide range of pedagogical approaches: from traditional methods and 3D modeling to gamification, the use of social media, and “flipped classroom” techniques. The congress highlighted the importance of integrating digital tools with classical teaching methods to enhance learning efficacy and motivate future medical professionals. The teaching experience in morphological disciplines presented at the congress, along with the participation of Russian specialists, can be beneficial for anatomy instructors in Russia in modernizing educational programs.