Terminological discrepancies and novelties in the histological description of the female genital system: proposed amendments for clinical-translational anatomy

Histological terminology of the female genital organs is currently a part of the internationally accepted nomenclature Terminologia Histologica (TH), the latest edition of which dates back to 2008. Many new discoveries have been documented within 16 years since then, and many discrepancies have been found. This paper aims to revise the terminology from clinical and educational perspectives comprehensively. The authors thoroughly searched the current edition of "Terminologia Histologica: International Terms for Human Cytology and Histology," focusing on missing and controversial terms in the chapter Female genital system. The authors identified six controversial and ambiguous terms and four missing important histological terms. The authors also discussed the addition of less used eponymic terms in the histological description of female genital organs like Hamperl cells, Popescu cells, Kroemer lacunae, Balbiani bodies, Call-Exner bodies, membrane of Slavianski, nabothian cysts, or anogenital sweat glands of van der Putte. We expect the second and revised edition of the TH to be published soon and hope that the Federative International Program on Anatomical Terminology will approve and incorporate all these propositions and suggestions. We also strongly recommend using the official internationally accepted Latin and English histological nomenclature-the TH, either in oral or written form, both in theoretical and clinical medicine.

Morphology of the immune cells in the wall of the human uterine tube and their possible impact on reproduction-uterine tube as a possible immune privileged organ

The uterine tube, as well as other parts of the upper female reproductive system, is immunologically unique in its requirements for tolerance to allogenic sperm and semi-allogenic embryos, yet responds to an array of sexually transmitted pathogens. To understand this dichotomy, there is a need to understand the functional morphology of immune cells in the wall of the uterine tube. Thus, we reviewed scientific literature regarding immune cells and the human uterine tube by using the scientific databases. The human uterine tube has a diverse population of immunocompetent cells representing both the innate and adaptive immune systems. We describe in detail the possible roles of cells of the mononuclear phagocyte system (macrophages and dendritic cells), T and B lymphocytes, natural killer cells, neutrophils and mast cells in association with the reproductive functions of uterine tubes. We are also discussing about the possible "immune privilege" of the uterine tube, as another mechanism to tolerate sperm and embryo without eliciting an inflammatory immune response. In uterine tube is not present an anatomical blood-tissue barrier between antigens and circulation. However, the immune cells of the uterine tube probably represent a type of "immunological barrier," which probably includes the uterine tube among the immunologically privileged organs. Understanding how immune cells in the female reproductive tract play roles in reproduction is essential to understand not only the mechanisms of gamete transport and fertilization as well as embryo transport through the uterine tube, but also in improving results from assisted reproduction.

The diagnostic significance of C4d deposits, as an immunohistochemical proof of complement activation, in kidney glomerular pathologies and kidney transplantation

C4d, a split product of C4 activation in classical and lectin pathways of the complement system activation, has been regarded as a footprint of tissue damage in antibody-mediated rejection in transplantology. The introduction of C4d staining into daily clinical practice aroused an ever-increasing interest in the role of antibody-mediated mechanisms in kidney allograft rejection. However, this marker of complement activation is also important in other various kidney glomerular pathologies such as immunoglobulin A nephropathy, membranoproliferative glomerulonephritis, lupus nephritis, and others. In routine histopathological practice, C4d staining can be done by two histological methods, specifically by immunofluorescence on frozen tissue using monoclonal antibody to C4d (with the downside of unsteady availability of frozen tissue) or by immunohistochemistry using C4d antibodies on formalin-fixed and paraffin-embedded renal tissue. The aim of this narrative review is to summarize recent knowledge about the complement fragment C4d and its significance in different kidney pathologies, focusing on its immunohistochemical detection in renal tissue biopsies. We have supplemented this review with our experience with our proprietary methodology of preparation and practical use of antibodies such as anti-C4d, on a small national level. Immunohistochemical staining for C4d has revolutionized the field of renal histopathology. Despite being a simple diagnostic test, its utility can be of utmost importance, especially in a resource-poor setting where immunofluorescence and frozen tissue may not be available (Fig. 2, Ref. 53). Keywords: C4d deposition, immunohistochemistry, kidney glomerular diseases, kidney transplant, renal tubular damage.

In-vitro antiplatelet effect of melatonin in healthy individuals and patients with type 2 diabetes mellitus

PURPOSE

The incidence of acute myocardial infarctions (AMI) shows circadian variation typically peaking during morning hours with a decline at night. However, this variation does not occur in patients with diabetes mellitus (DM). The night's decline of AMI may be partially explained by melatonin-related platelet inhibition. Whether this effect is absent in diabetic patients is unknown. The aim was to study the effect of melatonin on in-vitro platelet aggregation in healthy individuals and patients with type 2 DM.

METHODS

Platelet aggregation was measured in blood samples from healthy individuals (n = 15) and type 2 DM patients (n = 15) using multiple electrode aggregometry. Adenosine diphosphate (ADP), arachidonic acid (ASPI) and thrombin (TRAP) were used as agonists. Aggregability for each subject was tested after adding melatonin in two concentrations.

RESULTS

In healthy individuals, melatonin inhibited platelet aggregation in both higher (10-5 M) and lower concentrations (10-9 M) induced by ADP, ASPI, and TRAP (p < 0.001, p = 0.002, p = 0.029, respectively). In DM patients, melatonin did not affect platelet aggregation in both concentrations induced by ADP, ASPI, and TRAP. Melatonin decreased platelet aggregation induced by ADP, ASPI, and TRAP significantly more in healthy individuals compared to patients with DM. (p = 0.005, p = 0.045 and p = 0.048, respectively).

CONCLUSION

Platelet aggregation was inhibited by melatonin in healthy individuals. In-vitro antiplatelet effect of melatonin in type 2 DM patients is significantly attenuated.

The Evolution of Robin Sequence Treatment Based on the Biomimetic Interdisciplinary Approach: A Historical Review

The Robin sequence is a congenital anomaly characterized by a triad of features: micrognathia, glossoptosis, and airway obstruction. This comprehensive historical review maps the evolution of approaches and appliances for its treatment from the past to the current modern possibilities of an interdisciplinary combination of modern engineering, medicine, materials, and computer science combined approach with emphasis on designing appliances inspired by nature and individual human anatomy. Current biomimetic designs are clinically applied, resulting in appliances that are more efficient, comfortable, sustainable, and safer than legacy traditional designs. This review maps the treatment modalities that have been used for patients with a Robin sequence over the years. Early management of the Robin sequence focused primarily on airway maintenance and feeding support, while current management strategies involve both nonsurgical and surgical interventions and biomimetic biocompatible personalized appliances. The goal of this paper was to provide a review of the evolution of management strategies for patients with the Robin sequence that led to the current interdisciplinary biomimetic approaches impacting the future of Robin Sequence treatment with biomimetics at the forefront.

The Diagnostic Significance of C3d Antigen in Kidney and Skin Histopathology - The Current State-Of-The-Art and Practical Examples

The aim of this narrative review is to summarize recent knowledge about the diagnostic significance of immunobiological detection of C3d with a focus on renal and skin tissue biopsies. We completed the present narrative review with our own experiences with preparation and practical use of monoclonal C3d antibodies at a small national level.

The Neglected Uterine NK Cells/Hamperl Cells/Endometrial Stromal Granular Cell, or K Cells: A Narrative Review from History through Histology and to Medical Education

Reproductive immunology is at the forefront of research interests, aiming to better understand the mechanisms of immune regulation during gestation. The relationship between the immune system and the implanting embryo is profound because the embryo is semi-allogenic but not targeted by the maternal immune system, as expected in graft-versus-host reactions. The most prominent cell population at the maternal-fetal interface is the population of uterine natural killer (uNK) cells. Uterine NK cells are two-faced immunologically active cells, bearing comparison with Janus, the ancient Roman god of beginnings and endings. Their first face can be seen as natural killer cells, namely lymphocytes, which are critical for host defense against viruses and tumors. Even though uNK cells contain cytolytic molecules, their cytotoxic effect is not applied to classical target cells in vivo, playing a permissive rather than a defensive role. Their second face is crucial in maintaining physiological gestation-uNK cells show critical immunomodulatory functions with the potential to control embryo implantation and trophoblast invasion, regulate placental vascular remodeling, and promote embryonic/fetal growth. Therefore, we believe that their current designation "natural killer cells" (the first "cytotoxic" Janus's face) is misleading and inappropriate, considering their principal function is supporting and maintaining pregnancy. In this narrative review, we will focus on three lesser-known areas of knowledge about uNK cells. First, from the point of view of histology, we will comprehensively map the history of the discovery of these cells, as well as the current histological possibilities of their identification within the endometrium. To be brief, the discovery of uNK cells is generally attributed to Herwig Hamperl, one of the most influential and prominent representatives of German pathology in the 20th century, and his co-worker, Gisela Hellweg. Secondly, we will discuss the interesting aspect of terminology, since uNK cells are probably one of the human cells with the highest number of synonymous names, leading to significant discrepancies in their descriptions in scientific literature. From the first description of this cell type, they were referred to as endometrial granulocytes, granular endometrial stromal cells, or large granular lymphocytes until the end of the 1980s and the beginning of the 1990s of the last century, when the first publications appeared where the name "uterine NK cells" was used. The third area of present review is medical teaching of histology and clinical embryology. We can confirm that uNK cells are, in most textbooks, overlooked and almost forgotten cells despite their enormous importance. In the present narrative review, we summarize the lesser-known historical and terminological facts about uNK cells. We can state that within the textbooks of histology and embryology, this important cell population is still "overlooked and neglected" and is not given the same importance as in fields of clinical research and clinical practice.

Decellularization of the human urethra for tissue engineering applications

Recently, several scaffolds have been introduced for urethral tissue engineering. However, acellular human urethral scaffold harvested from deceased donors may provide significant advantages compared to synthetic, composite, or other biological scaffolds. This study aims to develop the protocol for decellularization of the human urethra that preserves substantial extracellular matrix (ECM) components, which are essential for subsequent recellularization mimicking the natural environment of the native ECM. A total of 12 human urethras were harvested from deceased donors. An equal part of every harvested urethra was used as a control sample for analyses. The protocol design was based on the enzyme-detergent-enzyme method. Trypsin and Triton X-100 were used to remove cells, followed by DNase treatment to remove DNA residues. Subsequently, the specimens were continually rinsed in deionized water for seven days. The efficiency of decellularization was determined by histochemistry, immunohistochemical staining, scanning electron microscopy (SEM), and DNA quantification. Histological analysis confirmed cell removal and preservation of urethral structure after decellularization. The preservation of collagen IV and fibronectin was confirmed by histologic examination and immunohistochemical staining. SEM confirmed the maintenance of the ultrastructural architecture of ECM and fibers. DNA content in decellularized urethra was significantly lower compared to the native sample (P < 0.001), and so the criteria for decellularized tissue were met. Cytotoxicity analysis data showed that the matrix-conditioned medium did not contain soluble toxins and had no significant inhibitory effect on cell proliferation, providing evidence that the decellularized samples are not toxic. This study demonstrates the feasibility of the enzyme-detergent-enzyme-based decellularization protocol for removing cellular components and maintaining urethral ECM and its ultrastructure. Moreover, obtained results provide solid ground for recellularization and urethral tissue engineering, which will follow.

Camptodactyly: From Embryological Basis to Surgical Treatment

Camptodactyly is a relatively rare hand deformity presenting as the proximal interphalangeal joint's nontraumatic and progressive flexion contracture. Most cases are limited to the fifth finger. The severity and type of camptodactyly should be considered to optimize treatment. Since many structures at the finger base can be involved in the pathogenesis of the deformity, surgical treatment for this particular type of deformity is challenging. This paper aims to bring insight into camptodactyly's pathogenesis and treatment options. We discuss the indication and pitfalls of surgical treatment options for particular camptodactyly types and present a case of a fourteen-year-old boy who was admitted to our department with proximal interphalangeal joint flexion contracture of the left fifth digit.

Congenital Proximal Radioulnar Synostosis in an Elite Athlete–Case Report

Background and Objectives: Proximal radioulnar synostosis (PRUS) is the most frequent congenital forearm disorder, although the prevalence in the general population is rare with a few hundred cases reported. Pfeiffer, Poland, Holt–Oram, and other serious congenital syndromes contain this abnormality. Non-syndromic cases with isolated PRUS very often exhibit as SMAD6, NOG genes variants, or sex chromosome aneuploidy. A subgroup of patients with haematological abnormalities presents with HOXA11 or MECOM genes variants. Case report: We present a non-syndromic adult elite ice-hockey player with unilateral proximal radioulnar synostosis of the left forearm. In early childhood he was able to handle the hockey stick only as a right-handed player and the diagnosis was set later at the age of 8 years due to lack of supination. Cleary–Omer Type III PRUS was found on x-ray with radial head hypoplasia and mild osteophytic degenerative changes of humeroulnar joint. Since the condition had minimal impact on sports activities, surgical intervention was not considered. The player continued his ice-hockey career at the top level and joined a national team for top tournaments. Upper extremity function assessment with questionnaires and physical testing resulted in minimal impairment. The most compromised tool was the Failla score with 10 points from a total of 15. Genetic testing with Sanger sequencing revealed no significant pathogenic variant in SMAD6, NOG, and GDP5 genes. No potentially pathogenic copy number variants were detected by array-based comparative genomic hybridization. Conclusions: In the reported case, the ability of an athlete to deal with an anatomic variant limiting the forearm supination is demonstrated. Nowadays, a comprehensive approach to rule out more complex musculoskeletal impairment and family burden is made possible by evolving genetics.

Traditional and contemporary views on the functional morphology of the fallopian tubes and their importance for gynecological practice

The uterine tube, belonging to the female internal reproductive organs, is the only tubular organ in the human body that has, under physiological conditions, a transport function occurring in two opposite directions. It transports the picked-up oocyte released during ovulation and early embryo towards the uterine cavity. At the same time, it can transport spermatozoa towards the abdominal opening of the fallopian tube. Moreover, the uterine tube has many other vital functions as sperm selection (one of the crucial factors preventing polyspermy) and the production of tubal fluid. This unique secretion is essential not only for the process of fertilization but also for sperm activation and the nourishment of the early embryo during its transport into the uterine cavity. The first part of our review is focused on the historical introduction to the topic in which the reader will become familiar with the views and understanding of these peculiar organs by famous anatomists of the 16th and 17th centuries, namely Gabriele Falloppio and Renier de Graaf. The following section will cover the overview of the latest anatomical, embryological, and histological knowledge, which are also crucial for a better understanding of pathological processes affecting the fallopian tube, such as tubal infertility or tubal pregnancy. Interestingly, recent years have been very fruitful regarding uterine tube morphology, e. g. the discovery of an unique mechanism of lymphatic flow within the uterine tube mucosa, the first description of immunologically-active intraepithelial suppressor T-lymphocytes, or the observation of pacemaker cell population - telocytes - in the muscle layer.

Autovaccines - potent tool against chronic vulvovaginal candidiasis

OBJECTIVE

Our aim was to determine the effect of immunomodulatory therapy in women with chronic and recurrent vulvovaginal candidiasis (RVVC).

BACKGROUND

We present recent highlights in the research into vaginal microbiome and consequences of chronic inflammation such as vulvovaginal candidiasis (VVC). VVC is a widespread vaginal infection primarily caused by Candida albicans. Experience of more than three episodes per year is defined as RVVC.

METHODS

The strains were isolated from women suffering from the above infections as for the period of 2017 to 2021 and subsequently used in immunomodulatory treatment. The preparation and administration of autovaccination therapy was performed using standard methodology and procedures cited in the manuscript.

RESULTS

In total, autovaccines were produced for 73 patients of whom 30 (41 %) were successfully cured by this treatment, 29 (40 %) experienced a partially successful treatment, and in the remaining 14 (19 %), the autovaccination therapy was ineffective.

CONCLUSION

We provide current knowledge about alternative (autovaccine) treatment options for female patients with VVC and RVVC diseases and our experience with the outcomes after autovaccine administration that currently has a promising therapeutic potential (Tab. 2, Ref. 18). Text in PDF www.elis.sk Keywords: autovaccines, chronic infections, vulvovaginal candidiasis, recurrent, Candida albicans.

Complications after administration of mRNA vaccine against COVID-19 - case report and short review

The pandemic of the disease COVID-19 (COronaVIrus Disease 2019) caused by the SARS-CoV-2 coronavirus (severe acute respiratory syndrome coronavirus 2) resulted in millions of deaths and many patients have chronic consequences after overcoming the acute condition. Several vaccines have been developed in an effort to stop the spread of the virus, but they have potentially serious adverse effects. We present a case report of a patient with acute (myocarditis, exacerbation of bronchial asthma) and long-term (postural orthostatic tachycardia syndrome - POTS) complications after vaccination with the second dose of mRNA vaccine BNT162b2 (Comirnaty®). Treatment consists of regimen measures, numerous pharmacotherapy (metoprolol, ivabradine, corticosteroids, antihistamines, antiphlogistics, bronchodilators) and several nutraceuticals (maritime pine bark extract, quercetin, vitamins, magnesium, phosphatidylcholine). In the discussion, we analyze post-vaccination injury and present a short review of the current literature.

Microbiota of female genital tract – functional overview of microbial flora from vagina to uterine tubes and placenta

Microorganisms and eukaryotic human cells coexist in synergistic relationships in nearly every niche of the human body. The female genital tract consisting of the vagina, uterus with its cervix and endometrium, uterine tubes and ovaries – harbors its own typical microbiota, which accounts for 9 % of the total bacterial population in females. To this organ system, we also assigned the microbiome of the placenta, which has not been studied much until now. Among the spectrum of microbial species, the female genital tract is mainly dominated by Lactobacillus species, which are considered to be one of the simplest yet most important microbial communities. However, this relationship between macro- and micro-organisms seems to have a number of physiological functions, e.g., the vaginal and cervical microbiota have unique impact on reproductive health. The aim of this review was to provide current view on female genital tract microbiota and its role in reproductive health. We describe in detail the association of vaginal or tubal epithelium with microbiota or the role of microbiota in normal placental function.

When Less Is More – Pipelle Endometrial Sampling for Quantification of Uterine Natural Killer Cells in Patients With Recurrent Implantation Failure or Habitual Abortion

Despite recent advancements in reproductive medicine, recurrent implantation failure and habitual abortion remain ongoing issues. One of the most important aspects of successful implantation is the intricate immune response and regulation necessary for the acceptance of the hemiallogenic embryo. The most numerous immune cells in the decidua are uterine natural killer cells (uNK). Studies suggest that changes in the uNK count and physiology may be responsible for the aforementioned pathological conditions. Thus, testing for uNK may provide valuable insights into their pathogenesis. The study compared Pipelle endometrial sampling with conventional curettage to find out whether the less invasive Pipelle method is a viable alternative of tissue collection. Tissue samples from 14 patients obtained by both methods were examined. The average size of tissue samples obtained with Pipelle was 17 mm2, samples obtained with curettage had on average 34 mm2. Using immunohistochemical visualization of CD56 (NK cells) and granzyme B antigens (serine protease-expressing activation state of NK cells), it was found that the average total count of CD56 / mm2 was 115 for Pipelle and 120 for curettage, respectively. The study also proved a correlation between granzyme B positivity and identification of NK cells clusters. The results indicated that Pipelle endometrial sampling seems a suitable method of tissue harvesting for the purpose of uNK cells examination. Pipelle endometrial sampling is safe, cost-effective and can be performed on an outpatient basis without the need of anesthesia or analgesia. Several issues remain yet to be solved: how to standardize the subsequent uNK testing, how to interpret the results and finally yet importantly, how to use this knowledge in personalized treatment protocols.

Uterine Natural Killer Cells in the Context of Implantation: Immunohistochemical Analysis of Endometrial Samples from Women with Habitual Abortion and Recurrent Implantation Failure

Infertility affects approximately 48 million couples globally. Despite the enormous progress of the methods of reproductive medicine that has been made since the first test-tube baby was born in 1978, the implantation rate of day-3 embryos is only around 15-20 % and 30 % of day-5 embryos. Numerous strategies aim to improve implantation rates and prevent repeated implantation failure. However, there is no specific general recommendation leading to satisfying results. One of the many risk factors relevant in this regard is the uterine immunological make-up, mainly the uterine Natural Killer (uNK) cells. They orchestrate the overall immune response during implantation by influencing trophoblast invasion and vascular remodeling and throughout pregnancy, uNK cells are also the main immune cells at the maternal–fetal interface. Previously, uNK count has been correlated with various fertility issues including idiopathic recurrent miscarriage. The present study used endometrial samples collected from 256 patients with recurrent implantation failure (RIF), habitual abortion (HA) and idiopathic sterility. Samples were collected between day 19 and 21 of the menstrual cycle mainly by Pipelle endometrial sampling. The samples were fixed in formalin for 24 hours and further processed for immunohistochemistry using anti-CD56 to visualize this antigen marker of uNK cells. Immunohistochemical counting was performed to assess the low, normal, or elevated count of uNK cells. According to the one-way ANOVA test, the age of our patients did not have any influence on the count of uNK cells. With Spearman correlation analysis, we found statistically significant correlation (p-value 0.05) of -0.133 between prior miscarriage and lower uNK cell count. Using the same analysis we found statistically significant correlation (correlation 0.233 with p value 0.01) between number of uNK cells and activation status. Patients with higher uNK cells were more frequenty diagnosed with endometriosis (p-value 0.05, correlation 0.130). Patients with an immunological factor of sterility (defined by a clinical immunologist) had a lower chance of gravidity (-0.203 with p-value 0.01). Based on our results, we can confirm that there is a correlation between RIF, HA, idiopathic sterility, endometriosis, and immunological factor of sterility (uNK cell count). The true predictive value with regard to fertility outcomes needs to be addressed in future research.

Our First Experience Implementing “Clinical Embryology and Reproductive Medicine” as a Curriculum Course of the Study Program General Medicine at the Faculty of Medicine in Bratislava, Slovakia

There is no separate course in the medical curriculum summarizing all aspects of human reproduction in most medical school curricula. At the same time, such a course would logically connect knowledge from clinical embryology and assisted reproduction, encompassing the issue of female and male infertility, mechanisms of birth defect formation, their prenatal diagnosis and subsequent specialized neonatal care. The aim of a wide team of university teachers comprising embryologists, gynecologists, neonatologists, endocrinologists, geneticists and others was to create and implement a new course entitled "Clinical Embryology and Reproductive Medicine" into the fourth-year curriculum of the study program General Medicine at the Faculty of Medicine, Comenius University in Bratislava. There has been a great interest in the course, as evidenced by the number of medical students enrolled. The lecture syllabuses have been divided into several thematic areas: 1) Clinical embryology including a laboratory part of assisted reproduction, 2) Cause and treatment options of female and male infertility, 3) A comprehensive view of the issue of birth defects, 4) The issue of preconception education, prenatal and childbirth training, family planning, 5) Reproductive immunology and endocrinology. Despite the complexity of human reproduction being a mainstay of gynecology and obstetrics, it is underemphasized in the medical school curricula worldwide. It is often reflected in shorter hospital / practical trainings during undergraduate studies and lower requirements at the final exam. Therefore, as students almost unanimously valued, this new course is extremely helpful in preparing for the final state exam.

Functional Morphology of the Human Uterine Tubes in the 21st Century: Anatomical Novelties and Their Possible Clinical Applications

The uterine tube (UT) pathologies account for 25-35 % of female factor infertility. Although these peculiar organs were first studied several hundred years ago, they have become overlooked and neglected mainly due to the successes of reproductive medicine. Nevertheless, reproductive medicine still faces many challenges regarding the fertility outcomes of in vitro fertilization (IVF). Many obstacles and problems can be resolved by a more detailed understanding of the UT morphology and function during normal reproduction. Over the course of the 21st century, many new insights have been obtained: the presence of a population of telocytes in the tubal wall responsible for normal motility and hormone sensory function, the demonstration of lymphatic lacunae of the mucosal folds necessary for oocyte capture and tubal fluid recirculation, or a thorough profiling of the immune makeup of the UT epithelial lining with the discovery of regulatory T cells presumably important for maternal tolerance towards the semi-allogenic embryo. New discoveries also include the notion that the UT epithelium is male sex hormone-sensitive, and that the UT is not sterile, but harbors a complex microbiome. The UT epithelial cells were also shown to be the cells-of-origin of high-grade serous ovarian carcinomas. Finally, yet importantly, several modern morphological directions have been emerging recently, including cell culture, the development of tubal organoids, in silico modelling, tissue engineering and regenerative medicine. All these novel insights and new approaches can contribute to better clinical practice and successful pregnancy outcomes.

Immunohistochemical and Scanning Electron Microscopic Confirmation of the Lymphatic Lacunae in the Uterine Tube Mucosal Folds. What Are the Clinical Implications?

Uterine tubes (UTs) are essential during physiological reproduction. The most intriguing part of its wall is the mucosa. Apart from the epithelial cells vital for its normal function, the connective tissue lamina propria contains wide spaces whose function, morphology and structure are yet to be elucidated. The present study used bioptic samples from 25 premenopausal (mean age 48.3 years, σ=3.56) and 25 postmenopausal women (mean age 57.8 years, σ=7.79). In both study groups, samples were obtained from two anatomically distinct parts of the UT – ampulla and infundibulum with fimbriae. The specimens were processed for scanning electron microscopy (SEM) and immunohistochemical detection of podoplanin (clone D2-40) and VEGFR-3 – two markers of lymphatic endothelial cells. The results showed that specimens from premenopausal and postmenopausal women contain wide lymphatic spaces, also known as lymphatic lacunae. The most probable function of the lacunae in the fimbriae is oocyte pick-up upon ovulation thanks to their ability to get engorged with lymph, thus serving as an erectile-like tissue. The ampullary lacunae are probably responsible for tubal fluid maintenance and recirculation. These results indicate that they are vital for normal reproduction because tubal fluid dynamics are as important as fluid composition. Further research on this topic is highly warranted because more detailed insights into UT function have a great potential to refine the methods of reproductive medicine, e.g. in vitro fertilization (IVF), which are still far from optimal regarding fertility outcomes.

Acellular Dermal Matrix in Plastic and Reconstructive Surgery

Despite significant advances in medical research, plastic surgeons still face a shortage of suitable patient tissues, and soft tissue reconstruction is no exception. In recent years, there has been a rapid boom in the use of acellular dermal matrix (ADM) in reconstructive and aesthetic surgery. ADM is incorporated into the surrounding tissue and gradually replaced by the host's collagen, thus promoting and supporting the healing process and reducing the formation of scar tissue. The main goal of this article is to provide a brief review of the current literature assessing the clinical applications of ADM across a broad spectrum of applications in plastic and reconstructive surgery.

Scanning electron microscopic study of the human uterine tube epithelial lining: surgical biopsy samples and epithelial cell culture

This article summarizes the importance of the exact morphology of human uterine/fallopian tube epithelium at the scanning electron microscopy (SEM) level for the clinical outcome even nowadays. Visual referential micrographs from SEM reflect two ways to view human epithelial cell lining surfaces: the surface epithelial uterine tube from surgical tissue biopsy and human fallopian tube epithelial cells (HFTEC) culture monolayer surface. One colorized image visualizes ciliated cells, distinguishes them from non-ciliated cells, and provides an educational benefit. A detailed description of the ultrastructure in referential and pathologic human uterine tube epithelium is important in defining the morphological basis of high-grade carcinomas, in the mechanism of pathophysiology, and in discussing options for its prevention. Cell cultures of human fallopian tube epithelial cells offer new approaches in simulating the mechanisms of cancer genesis or may help to elucidate the genetic basis of several diagnoses. New technical approaches in SEM provide higher resolution and detailed surface images. The SEM modality is still one of the current options in diagnostics and may be useful for advancing human reproductive organ cancer research.

The Overview of Anatomical Variations and Congenital Anomalies of the Uterine Tubes and Their Impact on Fertility

Anatomical variations and congenital anomalies of the uterine tubes (UTAVsCAs) are rare conditions, which are often undiagnosed, or accidentally diagnosed upon imaging, laparotomy, laparoscopy for unrelated condition, or during the Cesarean section. UTAVsCAs are often asymptomatic, but their clinical relevance lies in their possibly adverse impact on fertility. Since their rare occurrence, they are usually published as case reports. The most typically described are: agenesis of the uterine tubes (UTs), accessory UT (UT duplication), accessory UT ostium, and paratubal cysts (e.g. the hydatid cyst of Morgagni). UTAVsCAs are classified into an umbrella category of Müllerian duct anomalies (MDAs) which comprises anomalous development of all the organs developing from the paramesonephric (Müllerian) ducts, i.e., UTs, uterus and upper portion of the vagina. Interestingly, most of the classification systems of MDAs discuss solely the uterine and vaginal anomalies, while the UTs are often utterly ignored. This probably originates from the fact that UTs are no longer interesting for many clinicians as they think of UTs as superfluous organs whose function can be easily replaced in the in vitro fertilization (IVF) laboratory. Indeed, the modern reproductive medicine has been helping enormously with the conception of infertile couples. In many instances, the UTs are in fact successfully bypassed and a “test-tube” baby is born. Nevertheless, the UTs are still absolutely unique in providing suitable environment for fertilization and early embryo development - processes that hasn´t been still completely understood. This fact could partially explain why the success rate of IVF is “only” around 30-50 % depending on age. Therefore, the research of the UTAVsCAs is still clinically relevant in the context of reproductive medicine and should not be omitted from research endeavors.

A unique anatomical variation of the vascular supply of the ovary, uterine tube, and uterus from the greater omentum – an anatomical case study

It is well known that the blood supply of the greater omentum and female internal genital organs are not physiologically connected. There is also no mention of such anatomical variation in anatomical, radiological, or surgical textbooks. Here we present a very rare case report of atypical double arterial anastomosis (the first and second variant artery) between the right limb of the omental arcade of Barkow, uterus, and right ovary, which was found during a routine student anatomical dissection course. It is very challenging to find a proper explanation for the presence of the described anatomical variation; however, we hypothesized that it is based on their common embryonic origin - the mesentery. The first and second variant arteries could be remnants of transient anastomoses or collateral circulation, which were present during embryonic development and persisted until adulthood. Moreover, during our literature review, we noticed that the general description of omental blood supply and its possible variations is relatively poor; therefore, we emphasize the need for more precise knowledge regarding these anatomical parts, which could help surgeons who are performing abdominal or pelvic surgeries in preventing avoidable bleeding.

Is there a Need to Change the Basic Principles of Histology? Educational, Functional and Embryological Perspective

Although it is not an easy task to classify cells into different types, or in turn cell types into tissue types, a clear, understandable, didactically and clinically relevant tissue classification is indispensable for undergraduate medical education, expert discussions in biomedical research as well as for clinical practice. From the earliest discovery of the light microscope on, tissue classification has been a dynamic process. Historically, it was not a rare occurrence that different textbooks offered different tissue classifications. Nowadays, classifications have almost become uniform – the most common is the histological classification into four basic tissue types (epithelial, connective, muscle, nervous), which is recognized by the majority of modern histology and pathology textbooks. The reason is that, with some exceptions, this classification seems to be the most relevant not only for educational purposes but also from an embryological perspective and clinical-histopathological practice. Recently, attempts have been made to abandon this established classification and replace it with a new one. Any new classification, which would improve the presently used is welcomed. However, if the proposed innovation does not satisfy the needs of modern education and clinical practice, it should be handled with great caution or reconsidered.

From a Passive Conduit to Highly Dynamic Organ. What are the Roles of Uterine Tube Epithelium in Reproduction?

It is well known that the mammalian uterine tube (UT) plays a crucial role in female fertility, where the most important events leading to successful fertilization and pre-implantation embryo development occur. The known functions of these small intra-abdominal organs are: an uptake and transport of oocytes; storage, transportation, and capacitation of spermatozoa, and finally fertilization and transport of the fertilized ovum and early embryo through the isthmus towards the uterotubal junction. The success of all these events depends on the interaction between the uterine tube epithelium (UTE) and gametes/embryo. Besides that, contemporary research revealed that the tubal epithelium provides essential nutritional support and the most suitable environment for early embryo development. Moreover, recent discoveries in molecular biology help understand the role of the epithelium at the cellular and molecular levels, highlighting the factors involved in regulating the UT signaling, that affects different steps in the fertilization process. According to the latest research, the extracellular vesicles, as a major component of tubal secretion, mediate the interaction between gametes/embryo and epithelium. This review aims to provide up-to-date knowledge on various aspects concerning tubal epithelium activity and its cross-talk with spermatozoa, oocytes and preimplantation embryo and how these interactions affect fertilization and early embryo development.

Arterial Blood Supply of the Mesosalpinx Appears Segmentally Organized in Absence of Uterine Tubes Arteries

Arterial branches to the uterus and ovaries that pass through the mesosalpinx contribute significantly to the maintenance of the ovarian reserve. Especially arterial supply of the uterine tube is provided by a number of anastomoses between both the uterine and ovarian vessels. Knowledge on the morphologic peculiarities will allow to identify main contributors especially blood flow ultrasound examination for the purpose of ovary preserving surgery. This study aimed at identifying landmarks especially for so-called low-flow tubal vessels. Arteries of 17 female Thiel-embalmed bodies were studied along three preselected paramedian segments and measurements taken. A section was made through the center of the ovary perpendicular to uterine tube, then the mesosalpinx tissue distance was divided into 3 equivalent zones: upper, middle and lower thirds. The surface area of the mesosalpinx averaged 1088 ± 62 mm2. 47.7 ± 7.1 % of the mesosalpinx zones included macroscopically visible vessels. The lower third segment of mesosalpinx was the thickest averaging 2.4 ± 1.5 mm. One to three tubal branches were identified in the middle third of the mesosalpinx. Arterial anastomoses were found in the upper segment of the mesosalpinx, but no presence of a marginal vessel supplying the fallopian tube could be found. Statistically significant moderate positive correlations were established between the diameters of the mesosalpingeal arteries between the three zones. The mesosalpinx, uterine tube and the ovary form areas of segmental blood supply. Variants of tubal vessels appear to be a sparse source of blood supply.

Fabrication and In Vitro Characterization of Novel Hydroxyapatite Scaffolds 3D Printed Using Polyvinyl Alcohol as a Thermoplastic Binder

This paper presents a proof-of-concept study on the biocolonization of 3D-printed hydroxyapatite scaffolds with mesenchymal stem cells (MSCs). Three-dimensional (3D) printed biomimetic bone structure made of calcium deficient hydroxyapatite (CDHA) intended as a future bone graft was made from newly developed composite material for FDM printing. The biopolymer polyvinyl alcohol serves in this material as a thermoplastic binder for 3D molding of the printed object with a passive function and is completely removed during sintering. The study presents the material, the process of fused deposition modeling (FDM) of CDHA scaffolds, and its post-processing at three temperatures (1200, 1300, and 1400 °C), as well it evaluates the cytotoxicity and biocompatibility of scaffolds with MTT and LDH release assays after 14 days. The study also includes a morphological evaluation of cellular colonization with scanning electron microscopy (SEM) in two different filament orientations (rectilinear and gyroid). The results of the MTT assay showed that the tested material was not toxic, and cells were preserved in both orientations, with most cells present on the material fired at 1300 °C. Results of the LDH release assay showed a slight increase in LDH leakage from all samples. Visual evaluation of SEM confirmed the ideal post-processing temperature of the 3D-printed FDM framework for samples fired at 1300 °C and 1400 °C, with a porosity of 0.3 mm between filaments. In conclusion, the presented fabrication and colonization of CDHA scaffolds have great potential to be used in the tissue engineering of bones.

Pierre Robin Sequence and 3D Printed Personalized Composite Appliances in Interdisciplinary Approach

This paper introduces a complex novel concept and methodology for the creation of personalized biomedical appliances 3D-printed from certified biocompatible photopolymer resin Dental LT Clear (V2). The explained workflow includes intraoral and CT scanning, patient virtualization, digital appliance design, additive manufacturing, and clinical application with evaluation of the appliance intended for patients with cranio-facial syndromes. The presented concept defines virtual 3D fusion of intraoral optical scan and segmented CT as sufficient and accurate data defining the 3D surface of the face, intraoral and airway morphology necessary for the 3D design of complex personalized intraoral and extraoral parts of the orthopedic appliance. A central aspect of the concept is a feasible utilization of composite resin for biomedical prototyping of the sequence of marginally different appliances necessary to keep the pace with the patient rapid growth. Affordability, noninvasiveness, and practicality of the appliance update process shall be highlighted. The methodology is demonstrated on a particular case of two-year-old infant with Pierre Robin sequence. Materialization by additive manufacturing of this photopolymer provides a highly durable and resistant-to-fracture two-part appliance similar to a Tübingen palatal plate, for example. The paper concludes with the viability of the described method and material upon interdisciplinary clinical evaluation of experts from departments of orthodontics and cleft anomalies, pediatric pneumology and phthisiology, and pediatric otorhinolaryngology.

Dental Care and Education Facing Highly Transmissible SARS-CoV-2 Variants: Prospective Biosafety Setting: Prospective, Single-Arm, Single-Center Study

With the arrival of the highly transmissible Omicron variants (BA.4 and BA.5), dentistry faces another seasonal challenge to preserve the biosafety of dental care and education. With the aim of protecting patients, students, teachers and healthcare professionals, this paper introduces a prospective sustainable biosafety setting for everyday dental care and education. The setting developed by dental clinicians, epidemiologists, and teachers of dentistry consists of a combination of modern technologies focused on the air-borne part of the viral pathway. The introduced biosafety setting has been clinically evaluated after 18 months of application in the real clinical environment. The protocol has three fundamental pillars: (1) UVC air disinfection; (2) air saturation with certified virucidal essences with nebulizing diffusers; (3) complementary solutions including telehealth and 3D printing. A pseudonymous online smart form was used as the evaluation method. The protocol operates on the premise that everybody is a hypothetical asymptomatic carrier. The results of a clinical evaluation of 115 patient feedbacks imply that no virus transmission from patient to patient or from doctor to nurse was observed or reported using this protocol, and vice versa, although nine patients retrospectively admitted that the clinic visit is likely to be infectious. Despite these promising results, a larger clinical sample and exposition to the current mutated strains are needed for reliable conclusions about protocol virucidal efficiency in current dental environments.

Human Remains Identification Using Micro-CT, Chemometric and AI Methods in Forensic Experimental Reconstruction of Dental Patterns after Concentrated Sulphuric Acid Significant Impact

(1) Teeth, in humans, represent the most resilient tissues. However, exposure to concentrated acids might lead to their dissolving, thus making human identification difficult. Teeth often contain dental restorations from materials that are even more resilient to acid impact. This paper aims to introduce a novel method for the 3D reconstruction of dental patterns as a crucial step for the digital identification of dental records. (2) With a combination of modern methods, including micro-computed tomography, cone-beam computer tomography, and attenuated total reflection, in conjunction with Fourier transform infrared spectroscopy and artificial intelligence convolutional neural network algorithms, this paper presents a method for 3D-dental-pattern reconstruction, and human remains identification. Our research studies the morphology of teeth, bone, and dental materials (amalgam, composite, glass-ionomer cement) under different periods of exposure to 75% sulfuric acid. (3) Our results reveal a significant volume loss in bone, enamel, dentine, as well as glass-ionomer cement. The results also reveal a significant resistance by the composite and amalgam dental materials to the impact of sulfuric acid, thus serving as strong parts in the dental-pattern mosaic. This paper also probably introduces the first successful artificial intelligence application in automated-forensic-CBCT segmentation. (4) Interdisciplinary cooperation, utilizing the mentioned technologies, can solve the problem of human remains identification with a 3D reconstruction of dental patterns and their 2D projections over existing ante-mortem records.

Proapoptotic and antiapoptotic stimuli alternation in myocardial infarction experimental model

Myocardial infarction is a life-threatening complication of the coronary artery disease - the leading cause of premature death worldwide. The severity of this condition is the result of cellular death following the myocardial ischaemia, which occurs via several mechanism including apoptosis. For the research of this condition, animal models are often employed. We established isoprenaline-induced rat model of myocardial infarction, focusing on the immunohistochemical analysis of the expression of antiapoptotic and proapoptotic proteins BCL-2 and BAX, respectively. Apoptosis (based on BAX-positivity) was activated in cardiac muscle cells within the first day, later on day 8 also in fibroblasts of the forming scar tissue. Antiapoptosis in cardiac muscle cells was weak to moderate on the day 1 and 2, on the day 8 macrophages were strongly positive for BCL-2. The results confirmed that programmed cell death as well as mechanisms of antiapoptosis contribute to the pathogenesis of myocardial infarction. Previous research demonstrated that by experimentally affecting proapoptotic and antiapoptotic signals, it is possible to influence various aspects of myocardial infarction including: infarction size, cardiac remodelling and prognosis of the heart failure. Future research is warranted to fully elucidate the role of this process during myocardial infarction, which will result in refined diagnostic and therapeutic strategies (Tab. 1, Fig. 1, Ref. 21). Keywords: myocardial infarction, isoprenaline, apoptosis, necrosis, BCL-2, BAX.

Agenesis of female internal reproductive organs, the Mayer- Rokitansky-Küster-Hauser syndrome

OBJECTIVES

Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is the most common cause of uterine and uterine tubes absence/underdevelopment and the second most common cause of primary amenorrhea. It is characterized by a congenital agenesis of the uterine tubes, uterus, cervix, and upper part of the vagina. This study presents our 10 years of experience with the diagnostics and therapeutic management of patients with MRKH syndrome. We also focused on the description of anatomical deviations of the female reproductive organs.

MATERIALS AND METHODS

We studied a cohort of 16 patients hospitalized with MRKH syndrome between 2011-2020. We analysed the age at diagnosis, clinical signs and symptoms, diagnostic techniques, methods of neovagina creation, and anatomical anomalies of the female reproductive organs.

RESULTS

The mean age of our patients at the time of diagnosis was 16.75 years. The most frequent clinical manifestations were primary amenorrhea (56.25 %), pelvic pain (31.25 %) and coitus-associated problems. We used two methods of neovagina creation. In six patients we used the non-surgical Frank's dilators method. The vaginal length at the beginning of the dilation was 1.5-2 cm. In 4 patients the vaginal length was under 1 cm, so we performed surgical neovagina creation using the laparoscopic Vecchietti method. An-other two patients could create the vagina via regular sexual intercourse. Based on magnetic resonance imaging and ultrasound examination, the following anomalies were observed: complete agenesis of the uterus (50 % of cases), fibrous band (25 %) and rudimentary uterus (25 %).

CONCLUSIONS

Satisfactory results in the attempt to create a neovagina can be obtained by both non-surgical and surgical methods. Modern medicine provides many therapeutic measures, which make it possible for the affected women to have a normal sexual life (Tab. 1, Fig. 3, Ref. 37).

Artificial Intelligence in Orthodontic Smart Application for Treatment Coaching and Its Impact on Clinical Performance of Patients Monitored with AI-TeleHealth System

BACKGROUND

Treatment of malocclusion with clear removable appliances like Invisalign^® or Spark™, require considerable higher level of patient compliance when compared to conventional fixed braces. The clinical outcomes and treatment efficiency strongly depend on the patient's discipline. Smart treatment coaching applications, like strojCHECK^® are efficient for improving patient compliance.

PURPOSE

To evaluate the impact of computerized personalized decision algorithms responding to observed and anticipated patient behavior implemented as an update of an existing clinical orthodontic application (app).

MATERIALS AND METHODS

Variables such as (1) patient app interaction, (2) patient app discipline and (3) clinical aligner tracking evaluated by artificial intelligence system (AI) system-Dental monitoring^® were observed on the set of 86 patients. Two 60-day periods were evaluated; before and after the app was updated with decision tree processes.

RESULTS

All variables showed significant improvement after the update except for the manifestation of clinical non-tracking in men, evaluated by artificial intelligence from video scans.

CONCLUSIONS

Implementation of application update including computerized decision processes can significantly enhance clinical performance of existing health care applications and improve patients' compliance. Using the algorithm with decision tree architecture could create a baseline for further machine learning optimization.

Use of Advanced Artificial Intelligence in Forensic Medicine, Forensic Anthropology and Clinical Anatomy

Three-dimensional convolutional neural networks (3D CNN) of artificial intelligence (AI) are potent in image processing and recognition using deep learning to perform generative and descriptive tasks. Compared to its predecessor, the advantage of CNN is that it automatically detects the important features without any human supervision. 3D CNN is used to extract features in three dimensions where input is a 3D volume or a sequence of 2D pictures, e.g., slices in a cone-beam computer tomography scan (CBCT). The main aim was to bridge interdisciplinary cooperation between forensic medical experts and deep learning engineers, emphasizing activating clinical forensic experts in the field with possibly basic knowledge of advanced artificial intelligence techniques with interest in its implementation in their efforts to advance forensic research further. This paper introduces a novel workflow of 3D CNN analysis of full-head CBCT scans. Authors explore the current and design customized 3D CNN application methods for particular forensic research in five perspectives: (1) sex determination, (2) biological age estimation, (3) 3D cephalometric landmark annotation, (4) growth vectors prediction, (5) facial soft-tissue estimation from the skull and vice versa. In conclusion, 3D CNN application can be a watershed moment in forensic medicine, leading to unprecedented improvement of forensic analysis workflows based on 3D neural networks.

Variant Anatomy and Its Terminology

Variant anatomy, which is an integral part of anatomical science, is related to abnormalities in the human body structure. Our understanding of variant anatomy is based on thousand years of anatomical experience. These abnormalities generally do not interfere with the function of the human body and do not typically manifest as pathological nosological units. However, under certain conditions, these abnormalities can worsen existing pathological states or even evoke new ones. Understanding variant anatomy is a basic skill not only of mere anatomists, but also of clinicians who work in fields involving both diagnostic techniques and therapeutic interventions. To gain and retain a good knowledge of the most frequent and clinically relevant anatomical variations, a simple, clear, and exactly defined nomenclature of variant structures is needed. A list of items comprising variant anatomy, which have been incorporated into the internationally accepted nomenclatures Terminologia Anatomica (1998) and Terminologia Neuroanatomica (2017), is described and analyzed. Examples of the most common anatomical variations related to terminology are mentioned, and variant anatomy as a whole and its role in understanding current anatomy are discussed.

Hirschsprung's Disease-Recent Understanding of Embryonic Aspects, Etiopathogenesis and Future Treatment Avenues

Hirschsprung's disease is a neurocristopathy, caused by defective migration, proliferation, differentiation and survival of neural crest cells, leading to gut aganglionosis. It usually manifests rapidly after birth, affecting 1 in 5000 live births around the globe. In recent decades, there has been a significant improvement in the understanding of its genetics and the association with other congenital anomalies, which share the pathomechanism of improper development of the neural crest. Apart from that, several cell populations which do not originate from the neural crest, but contribute to the development of Hirschsprung's disease, have also been described, namely mast cells and interstitial cells of Cajal. From the diagnostic perspective, researchers also focused on "Variants of Hirschsprung's disease", which can mimic the clinical signs of the disease, but are in fact different entities, with distinct prognosis and treatment approaches. The treatment of Hirschsprung's disease is usually surgical resection of the aganglionic part of the intestine, however, as many as 30-50% of patients experience persisting symptoms. Considering this fact, this review article also outlines future hopes and perspectives in Hirschsprung's disease management, which has the potential to benefit from the advancements in the fields of cell-based therapy and tissue engineering.

The Syndrome of Elongated Styloid Process, the Eagle's Syndrome-From Anatomical, Evolutionary and Embryological Backgrounds to 3D Printing and Personalized Surgery Planning. Report of Five Cases

Background and Objectives: The symptoms of Eagle's syndrome are associated with the elongated styloid process of the temporal bone or calcification of the stylohyoid ligament. The first mention of pain syndrome associated with the elongated styloid process dates back to 1937, when it was described by Watt Weems Eagle. Over the last decade, experts in the field have shown a lively interest in the issue of the relationship between the elongated styloid process and various symptoms. This article presents the correlation between the clinical signs of Eagle's syndrome and alterations in surrounding anatomical structures. It includes a brief review of the evolutionary, embryological and clinical anatomical background of the elongated styloid process. Materials and Methods: Between 2018 and 2019, five patients were admitted to our workplace with 1-3-year history of bilateral or unilateral throat pain, otalgia and pharyngeal foreign body sensation. As a therapeutic novelty in the surgical approach to this condition, we used individual 3D printed models to measure and identify the exact location of the resection of the styloid process without damaging the surrounding anatomical structures, such as the facial, accessory, hypoglossal, and vagal nerves; the internal jugular vein; and the internal carotid artery. Results: Compared to traditional surgical methods without 3D models, 3D models helped to better identify cutting edges and major landmarks used in surgical treatment of Eagle's syndrome. Printed models provided assistance with the exact location of the styloid process resection position without damaging the surrounding anatomical structures such as the facial, accessory, hypoglossal, and vagal nerves; the internal jugular vein; and the internal carotid artery. Conclusion: In our clinical report, we used 3D printed models for navigation and planning during surgical procedures involving resections of the elongated styloid process. Additionally, we can formulate a new hypothesis: the elongated styloid process is a form of atavism of the bony hyoid apparatus in our evolutionary ancestors that is evolutionarily encoded or arises from disrupted degeneration of the middle portion of embryonal Reichert´s cartilage of the second pharyngeal arch. Under normal conditions, this portion does not ossify but degenerates and transforms into a connective tissue band, the future stylohyoid ligament.

Impaired histomorphology might provoke cell cycle regulators alteration in thymus of children with various congenital heart defects

Thymus, as a primary site of appropriate adaptive immunity formation, is an essential organ in face of a self-tolerance as well as a potential menace from impairment of body integrity. Due to vital selection processes during differentiation and maturation of T lymphocytes, control over cell survival and programmed cell death must be orchestrated in detail. Indeed, thymus is highly sensitive to wide spectrum of stressors that initiate acute structural changes. Hypoxia, one of the most common complications in congenital heart defects (CHDs) patients, provokes stress-induced thymus involution. Disrupted embryolonic development of thymus in association with congenital heart defects, may negatively affect physiological immune mechanisms. We propose that detailed analysis of thymic morphology could critically contribute to unveil the pathophysiology of diseases associated with disrupted adaptive immunity in children with heterogeneous congenital heart diseases.

Trnka Vaclav - Central European Anatomist and Medical Polymath of the Eighteenth Century

Vaclav Trnka from Křovice (1739-1791, in Latin: Wenzel Trnka Krzowitz) was a remarkable physician whose life serves as an example in the history of medicine by connecting major capital cities of Central Europe. In view of current geographical layout, he was born and brought up in the Czech Republic, graduated from University of Vienna in Austria, and was appointed Professor of the Anatomy at the newly established Faculty of Medicine of University of Nagyszombat, presently Trnava in Slovak Republic. When the University moved to Buda and later to Pest (today Budapest, Hungary), he was the first educator to introduce anatomy as a medical subject to be taught in a Hungarian medical school. He also was elected the Dean of Faculty of Medicine three times and in 1786-1787 he acted as Rector of then the Royal University of Pest. During his life, he published twenty-seven monographs dealing with different areas of clinical medicine, such as malaria (intermittent fever), diabetes, and rickets. Based on these monographs we can proclaim that Václav Trnka was a co-founder of modern infectology, diabetology and ophthalmology in Central Europe. Nowadays, artificial intelligence and bioinformatics are inseparable parts of modern health care system which help the transformation of big data into valuable knowledge. In the 18th century, Professor Trnka owned more than 3,000 scientific books and had natural, innate intelligence and wisdom which made him a real "medical polymath". As a musician, Trnka also composed sixty-one canons, two of them long wrongly considered as Mozart's work. Despite the fact that Trnka is considered to be the founder of Hungarian anatomy education and a major medical figure of the eighteenth century Central Europe, no internationally acclaimed biographical record of his life or work has so far been published in English. Therefore, we would like to reintroduce Václav Trnka both as an anatomist and medical polymath, and to give an overview of the early days of anatomy teaching in present-day Slovakia and Hungary (Fig. 1, Ref. 27). Keywords: Trnka from Křovice, anatomist, medical polymath, history of medicine.

Ectopic lamellar Pacinian corpuscle within the thymus. Atypical or abnormal location?

Lamellar (Pacinian) corpuscle is a cutaneous encapsulated sensory corpuscle, mainly functioning as a rapidly adapting low-threshold mechanoreceptor with characteristic "onion skin"-like appearance. Even though the Pacinian corpuscle is typically located in the skin, histomorphologically and confirmed by using immunohistochemical methods, we have identified it within the interstitium of the thymus of a newborn with congenital heart defect. To the best of our knowledge, this is the first such account ever to be published. The structure of the thymic Pacinian corpuscle was the same as the Pacinian corpuscle in the skin. The ectopic thymic Pacinian corpuscle can be hypothetically explained as the consequence of impaired migration of neural crest cells, since neural crest-derived cells play an important role in the development of the Pacinian corpuscle, as well as the thymus and heart. In general, the occurrence of ectopic Pacinian corpuscle in different organs is rare. In the scientific literature, there are reports of its sporadic presence in the pancreas, in the lymph nodes, inside the prostate and the urinary bladder wall. Our report presents the first described case of the Pacinian corpuscle in a heterotopic location in the thymus. Similar to other incidental findings of this anatomic structure, explanation of its ectopic development, as well as its local function remains only speculative.

Fertility maintenance in male oncological patients: current state and future perspectives

Growing cancer incidence in reproductive age goes hand in hand with a rising survival rate of patients who underwent anticancer therapy. This trend points to the necessity of discussion regarding the fertility maintenance. The patient´s future with respect to his reproductive ability has to be addressed properly to achieve a complex approach to cancer management. The germinal epithelium of the testes is highly susceptible to deleterious effects of chemotherapy. After the administration of gonadotoxic chemotherapeutic agents, a patient can develop oligospermia, or even azoospermia. Similarly, radiation exposure can damage spermatogenesis, while higher doses lead to azoospermia. This review brings an overview of the methods of assisted reproduction, which are currently in use for fertility maintenance in oncological patients, but also in those with non-malignant indications. Also, novel, yet still experimental, methods are discussed, which represent promising technologies applicable to prepubertal oncological patients. We also discuss historical milestones in the development of assisted reproduction, summarize the options of semen analysis, and we present a practical guide through the process of sperm cryopreservation and subsequent in vivo or in vitro fertilisation. We deem that fertility maintenance should be an integral part of the health care in oncological patients in reproductive age (Tab. 1, Ref. 85). Keywords: assisted reproduction technique, sperm cryopreservation, testicular tissue cryopreservation, spermatogenesis, sperm quality in oncological patients.

Bioengineered Scaffolds as Substitutes for Grafts for Urethra Reconstruction

Urethral defects originating from congenital malformations, trauma, inflammation or carcinoma still pose a great challenge to modern urology. Recent therapies have failed many times and have not provided the expected results. This negatively affects patients' quality of life. By combining cells, bioactive molecules, and biomaterials, tissue engineering can provide promising treatment options. This review focused on scaffold systems for urethra reconstruction. We also discussed different technologies, such as electrospinning and 3D bioprinting which provide great possibility for the preparation of a hollow structure with well-defined architecture.

A plea for extension of the official nomenclature of the microscopic structure of human tissues and organs, the Terminologia Histologica

BACKGROUND

At first sight, the issue of terminology in morphological sciences may seem as "closed and changeless chapter", as many of the structures within the human body have been known for centuries. However, the exact opposite is true. Terminologia Histologica: International Terms for Human Cytology and Histology published under the Federative International Programme on Anatomical Terminology in 2008 is a new standard in human cell and tissue terminology. The list of items in the first and still valid official nomenclature of cellular and tissue structures, the Terminologia Histologica (TH), is the best and most extensive of all the histological nomenclatures ever issued.

MATERIALS AND METHODS

The aim of this article is a systematic and in-depth analysis of the current internationally accepted nomenclature TH, with focus on important histological structures which are missing in this first edition. Some should be incorporated just for the sake of completeness and consistence, others are purely absent terms for individual structures or some are recently described new tissue structures.

RESULTS

We also discuss about a question, how to deal with the issue of eponyms. Eponyms reflect medicine's rich and colourful history. Although they have not been considered official terms in the anatomical nomenclature since 1955, they are still widely used in clinical practice.

CONCLUSIONS

We hope that this opinion article will develop a wide scientific discussion before the publication of the second edition, so perhaps the mentioned minor flaws will be corrected, so the new edition of the TH will become truly an internationally accepted communication tool for all histologists, histopathologists and anatomists.

Sentinel lymph node - historical background and current views on its significance in complex management of breast cancer patients

Nowadays, breast cancer is the leading oncological diagnosis in women worldwide. On the other hand, breast cancer treatment can be considered one of the most progressive therapeutic approach in the medical field of oncology. The invasive types of breast cancer have a tendency to spread via lymphatic route, what brings in the issue of sentinel lymph node - the first node into which the lymph drains from a given anatomical location. This review paper discusses the historical background of the concept of sentinel lymph node and focuses on clinical significance of the positivity of sentinel lymph node(s) as well. Modern-day conservative therapeutic surgery of breast cancer should be in accordance with diagnostic and preventive interventions in the axilla, whose rate of invasiveness and morbidity must be also attenuated without worsening the patient´s prognosis and survival rate. Formerly, a complete axillary lymph node dissection was routinely performed for prophylactic and cancer staging purposes. The indiscriminate application of this approach was replaced by sentinel lymph node biopsy. Along with common histopathological examination, immunohistochemistry, as well as modern techniques of molecular biology are often employed. These state-of-the-art methods enabled the identification of micrometastases, or even nanometastases, though their real prognostic value is yet to be concluded (Ref. 52). Keywords: sentinel node, breast cancer, biopsy, historical background.