MICROCIRCULATORY SYSTEM OF THE SKIN (DEMONSTRATION MATERIALS OF STUDENTS AND YOUNG SCIENTISTS)

The subject of research – the structure of the microcirculatory tract of the skin. The purpose of the work is to provide demonstration materials of students and young scientists of the microcirculatory system of the skin. Even in the modern scientific literature there are many contradictions about the relationship of structural components that form the microcirculatory system of the skin, which dictates the need for further research on the relationship of various blood vessels with other components of the so-called microcirculatory system.Key words: microcirculatory system of skin, demonstration materials.

Blood Particulate Analogue Fluids: A Review

Microfluidics has proven to be an extraordinary working platform to mimic and study blood flow phenomena and the dynamics of components of the human microcirculatory system. However, the use of real blood increases the complexity to perform these kinds of in vitro blood experiments due to diverse problems such as coagulation, sample storage, and handling problems. For this reason, interest in the development of fluids with rheological properties similar to those of real blood has grown over the last years. The inclusion of microparticles in blood analogue fluids is essential to reproduce multiphase effects taking place in a microcirculatory system, such as the cell-free layer (CFL) and Fähraeus–Lindqvist effect. In this review, we summarize the progress made in the last twenty years. Size, shape, mechanical properties, and even biological functionalities of microparticles produced/used to mimic red blood cells (RBCs) are critically exposed and analyzed. The methods developed to fabricate these RBC templates are also shown. The dynamic flow/rheology of blood particulate analogue fluids proposed in the literature (with different particle concentrations, in most of the cases, relatively low) is shown and discussed in-depth. Although there have been many advances, the development of a reliable blood particulate analogue fluid, with around 45% by volume of microparticles, continues to be a big challenge.

Case Report: Sublingual Microcirculatory Alterations in a Covid-19 Patient With Subcutaneous Emphysema, Venous Thrombosis, and Pneumomediastinum

The Corona virus disease 2019 (Covid-19) has brought a wide range of challenges in intensive care medicine. Understanding of the pathophysiology of Covid-19 relies on interpreting of its impact on the vascular, particularly microcirculatory system. Herein we report on the first use of the latest generation hand-held vital microscope to evaluate the sublingual microcirculation in a Covid-19 patient with subcutaneous emphysema, venous thrombosis and pneumomediastinum. Remarkably, microcirculatory parameters of the patient were increased during the exacerbation period, which is not a usual finding in critically ill patients mostly presenting with a loss of hemodynamic coherence. In contrast, recovery from the disease led to a subsequent amelioration of these parameters. This report clearly shows the importance of microcirculatory monitoring for evaluating the course and the adequacy of therapy in Covid-19 patients.

Morphological assessment of the mucous membranes of the bladder and vagina in chronic cystitis in women

The study involved 107 women aged 20 to 52 years with chronic recurrent cystitis (57 of them with leukoplakia) developing under conditions of a pathogenic and/or opportunistic infection. All patients underwent a conventional clinical and instrumental examination. Biopsy samples for culture-based and microscopic examination were taken from the area of the Pawlik’s trigone of the vagina and the Lieutaud’s trigone of the urinary bladder, in case of leukoplakia — from the field of visually healthy tissue. The carried out cytomorphological analysis and assessment of pathological processes in the adjacent tissues suggest that the infection from the vagina penetrates through the intersynaptic clefts, interstitial cell nests, the blood and lymphatic microcirculatory system into the bladder, causing cystitis inherent changes — from initial morphological forms to rough ones, up to leukoplakia. A complex of clinical, functional and pathomorphological changes that fit into the framework of the chronic cystovaginitis concept was identified.