Application of imprint cytology in assessment of immunological effects of isolated and combined action of selenium and copper nanoparticles

Introduction. Touch Imprint Cytology as the method of impression cytology of smears-prints is of great diagnostic value not only in clinical practice but is also of interest as an express method for assessing the immunological effects of the influence of metal-containing nanoparticles on the tissues of laboratory animals in an experiment. Materials and methods. The study involved the spleen and mesenteric lymph nodes (MLN) of outbred male rats (24 individuals), with an initial weight of 220-230 g, after subchronic intoxication, which was caused by repeated intraperitoneal injections of metal-containing nanoparticles of selenium (SeO) and copper (CuO) nanoparticles (NPs) at a dose of 0.5 mg/kg and their combination three times a week (a total of 18 injections). After sacrificing the rats by decapitation, the spleen and MLN were removed from the animals from each group; made smears were dried at room temperature. Stained according to Leishman. Cell composition and cytological signs were assessed in a light binocular microscope by Carl Zeiss Primo Star with a USCMOS video imaging system at a magnification of 100x and 1000x under cytological criteria. Cell counting in the analysis of spleen and MLN preparations was carried out in percentage - 100 cells from each smear (48 studies), as well as calculating the number of cellular elements per 1 mm2 of the smear surface area, by calculating the absolute amount of each cellular element in the microscope field of view of 0.03 mm2, followed by recalculation per 1 mm2 (the number of studies is 48). Differences between the mean group quantitative results were processed using Student’s criteria using Excel software. Differences between mean values were considered statistically significant if the probability of a random difference did not exceed 5% (p < 0.05). Results. The main results obtained in the study of cytomorphological parameters of smears - spleen prints and MLN of rats after exposure to SeO and CuO NPs, both independently and their combination using two methods for calculating the cellular composition of preparations, are presented. The main changes in the cellular composition during immunological effects are highlighted. Inflammatory reactions of the hyperergic type were revealed when exposed to selenium nanoparticles, both in autonomous action and in combination with copper nanoparticles. The formation of local cellular immunity was noted due to an increase in the level of plasma cells in smears imprints when exposed to copper nanoparticles. Conclusion. Using the impression method of smears-prints in conjunction with the histological examination of tissue preparations allows iimplementing complete cytomorphological parameters in studying the immunological effects of metal-containing nanoparticles.

Stability Analysis and Experimental Research on Ultrasonic Cutting of Wave-absorbing Honeycomb Material With Disc Cutter

To address the problem of the poor stability of ultrasonic machining of wave-absorbing honeycomb materials, this paper takes ultrasonic cutting of wave-absorbing honeycomb materials with a disc cutter as the research object and establishes a multi-degree-of-freedom mathematical model of the cutting system based on the relative positions of the tool and the honeycomb material and the motion characteristics of the tool. On this basis, modal analysis of the disc tool and the honeycomb cellular element wall plate is carried out to draw the Lobe diagram of ultrasonic cutting stability, the process experimental parameters are determined according to the solved stability Lobe diagram, and machining stability verification experiments are carried out. The experimental results show that the machining parameters in the stable region of the Lobe diagram result in a neat and clean surface, less fibre pullout, a complete outer substrate, and less tool wear than those in the critical and unstable regions, thus verifying the correctness of the theoretical model and the stability Lobe diagram.

Two Faces of Regulatory T Cells: From Immune Defense to Tumoral Progression

T cells are the most important cellular element of human immunity defending against virus, bacteria, non-self-tissue and tumor cells. Regulatory T cells (Tregs) are the major responsible for self-tolerance maintenance, especially those expressing forkhead box protein 3 (FOXP3) transcription factor. Tregs suppressive function is established through several mechanisms that are essential to immune system homeostasis, but also related to tumoral microenvironment. Recent studies have provided deeper understanding of Tregs role in cancer as well as promising therapeutic targets for improving prognosis in cancer patients. This review approaches Tregs subtypes, functions and its implication in tumor progression.

FEATURES OF REPARATIVE REGENERATION OF ACHILLES TENDON IN THE CONDITIONS OF AUTOLOGOUS TRANSPLANTATION OF CELL POOL

The aim of the study is identification of features of Achilles tendon healing in the conditions of auto-transplantation of the cellular element, reflecting the regenerative activity of stromal-vascular fraction. Modern regenerative treat-ment methods for animal with tendon injuries involve stromal-vascular cells application of adipose tissue. They represent cell pool with high plasticity, proliferative activity, and ability to secrete multiple angiogenic factors. How-ever, there is no data on morphological and morphometric regenerative equivalents of their use in case of tendon ligaments injury. Micro morphometrical indicators are presented that substantiate the effectiveness of using autolo-gous cellular elements in case of Achilles tendon injury. The influence of stromal-vascular fraction from rat adipose tissue on regenerative process during healing of an induced tendon tissue defect was evaluated which lead to an increase in the thickness of bundles of the first and the second orders in the experimental group, significant differ-ences in comparison with the control of the fibroblastic cell pool, and the number of blood capillaries of these ani-mals. Based on the positive data of the autologous cell pool on the regenerative ability of the Achilles tendon, its practicability for veterinary medicine was scientifically justified. The experimental model of the study is a fancy rat (n=20). Achilles tendon was the research material. A complex methodological approach was used, including ex-perimental modeling, micro morphological studies, micro morphometry, and statistical data processing. It was re-vealed that experimental animals injected with stromal-vascular fraction, micro morphometric transformations of connective tissue were detected, aimed at thickening of bundles of the first and second orders, the transition of fi-broblasts to structured and ordered fibrocytes (tenocytes), acceleration of collagenogenesis and vascularization enhancement.

MAPK/ERK Dysfunction in Neurodegenerative Diseases

The signaling pathway of the microtubule-associated protein kinase or extracellular regulated kinase (MAPK/ERK) is a common mechanism of extracellular information transduction from extracellular stimuli to the intracellular space. The transduction of information leads to changes in the ongoing metabolic pathways and the modification of gene expression patterns. In the central nervous system, ERK is expressed ubiquitously, both temporally and spatially. The MAP-ERK pathway is a key element of the neuroinflammatory pathway triggered by glial cells during the development of neurodegenerative diseases, such as Parkinson&rsquo;s and Alzheimer&rsquo;s disease, Huntington&rsquo;s disease, and amyotrophic lateral sclerosis, as well as prionic diseases. The process triggered by MAPK/ERK activation depends on the stage of development (mature or senescence), the type of cellular element in which the pathway is activated, and the anatomic neural structure. However, extensive gaps exist with regards to the targets of the phosphorylated ERK in many of these processes.

METHOD OF PREPARING CYTOLOGICAL PRODUCTS USING AN ULTRASONIC BATH

The article presents a new technique for the preparation of cytological preparations, which can significantly increase the yield of cellular elements from traces of biological origin on material evidence. The use of this technique increases the percentage of positive results when conducting forensic cytological studies. The study found that the use of an ultrasound bath in forensic examination of cigarette butts increases the number of cells removed by an average of 5-7 times compared to the conventional method of preparation of cytological drugs. The analysis of the data also indicates that the storage time of cigarettes in the laboratory does not significantly affect the amount of cellular element extraction. Some difference in the average number of cells, for example, the shelf life of 1 month and 3 months, can be explained by the “dry” way of smoking cigarettes. The use of this method in the examinations showed that ultrasound treatment does not affect the further investigation of these deficiencies in order to identify the antigens of the ABO system and to establish the category of excretion of smokers. The application of this method makes it possible to use much less material in the examinations, and treatment with saline solution allows to save the biomaterial for further research by the method of DNA analysis. Thus, the use of an ultrasound bath for the preparation of cytological preparations for cigarette butts can be recommended to forensic experts-cytologists for practical work, which will significantly increase the percentage of positive results in establishing the sex of saliva on these objects.

Biochemical and hematological composition of blood of cattle fed with Chlorella

We researched the influence of the additive Chlorella cultivated in a closed bioreactor under the influence of an electrostatistic field, on the biochemical and hematological parameters of blood in different age groups of cattle. The experiment was conducted on two groups of three month old heifers and two groups of lactating cows in the 7th month of lactation, with 15 individuals in each group; all animals in the groups were given the basic diet. During the 120-day experiment, the experimental group of heifers was fed on a suspension of Chlorella cultivated with the technology using an electrostatic field, in the following amounts: 1–30th day – 1.51 g, 31–60th day – 1.82 g, 61–90th day – 2.01 g, 91–120th day – 2.28 g of dry substance per individual daily; the group of lactating cows during 60 days was given the Chlorella additive to the amount of 6 g of dry substance per individual per day. Over the following 30 days the heifers and lactating cows were kept under observation to determine the “aftereffects” of the Chlorella suspension fodder additive. On the first day of the experiment and after every 30 days, blood was drawn from the animals’ jugular veins for determination of the biochemical and hematological parameters of the blood During the experiment, the experimental groups of heifers and lactating cows were observed to have a strengthened antioxidant system due to increase in the activity of superoxide dismutase and catalase, and also to have a strengthened hematopoietic function and intensified metabolic and redox processes. Due to the stimulating effect of the suspension of Chlorella cultivated using the intense technology involving using an electrostatic field on the erythro- and leukopoiesis of different age groups of the cattle, we determined a strengthening of the cellular element of the animals’ immune system. During the following 30 days, the heifers and lactating cows of the experimental groups were observed to exhibit “aftereffects” of the Chlorella suspension additive, namely increases in the values of biochemical, hematological and morphological indicators of the blood in comparison with these indicators for the animals in the control groups. As a result, we concluded that feeding different age groups of cattle with suspension of Chlorella cultivated in the conditions of a closed bioreactor under the influence of an electrostatic field, in the dosage of 155 ml per kg of dry substance of the animals’ diet, contributes to the strengthening of non-specific defence of their organism, forming a potential for increasing the productive indicators and maintenance of the livestock.

Histomorphological study of the spleen in indigenous Gazelle (Gazella subgutturosa)

The study aimed to investigate the anatomical and histomorphometrical features of spleen in gazelle. To achieve this goal, spleens of 7 animals were used. The gross aspect of the study revealed that the spleen of gazelle appeared dark brown in color with elliptical shape and was situated at the left lateral surface of the rumen. It occupied the area extended from the 8th rib to 11th rib. Length and width of the spleens were calculated and the mean were 7.94±0.1, 5.88±0.2 respectively. There were three ligaments connected the spleen with adjacent structures, namely splenogastric, splenorenal and splenophrenic. The blood supply of the spleen was studied using X-rays and resin injection methods. The splenic artery was divided into three primary branches, each one subdivided into two secondary branches. The latter branched into tertiary branches which were distributed all over the splenic parenchyma. Microscopic findings showed that the capsule of spleen in gazelle was composed from of two layers, the outer one made of mainly of dense connective tissue; whereas the inner layer of capsule consisted of connective tissue fibers in addition to abundance of smooth muscle fibers interweaving among them. The total mean thickness of the capsule was 210.51+8.3 µm. The splenic parenchyma in gazelle consisted of white pulp represented by lymphoid follicles with their marginal zones and periarterial lymphatic sheath while the red pulp represented by splenic cords and sinusoids. The area of white pulp in the gazelle comprised about 9.6% of the spleen parenchyma. Red pulp composed mainly from cords of connective tissue and small sinuses or sinusoids filled with blood cellular element which extended among these cords and was lined by flattened endothelial cells with relatively large spaces or slits between them. The sinusoids were found to be lymphocytes, reticular, plasma, macrophages and occasional megakaryocytes whereas the megakaryocyte appeared large with acidophilic cytoplasm and dark elongated multilobated nucleus. This research work was performed in order to establish the basic histomorphological information helpful for the veterinary medical practice and veterinary surgions to developing their work on gazelle like designing the approach of some surgical operations like spleenectomy or any surgical entrance may be needed in these animal species.

An Enhanced Spring-Particle Model for Red Blood Cell Structural Mechanics: Application to the Stomatocyte–Discocyte–Echinocyte Transformation

Red blood cells (RBCs) are the most abundant cellular element suspended in blood. Together with the usual biconcave-shaped RBCs, i.e., discocytes, unusual-shaped RBCs are also observed under physiological and experimental conditions, e.g., stomatocytes and echinocytes. Stomatocytes and echinocytes are formed from discocytes and in addition can revert back to being discocytes; this shape change is known as the stomatocyte–discocyte–echinocyte (SDE) transformation. To-date, limited research has been conducted on the numerical prediction of the full SDE transformation. Spring-particle RBC (SP-RBC) models are commonly used to numerically predict RBC mechanics and rheology. However, these models are incapable of predicting the full SDE transformation because the typically employed bending model always leads to numerical instability with severely deformed shapes. In this work, an enhanced SP-RBC model is proposed in order to extend the capability of this model type and so that the full SDE transformation can be reproduced. This is achieved through the leveraging of an advanced bending model. Transformed vesicle and RBC shapes are predicted for a range of reduced volume and reduced membrane area difference (MAD), and very good agreement is obtained in the comparison of predicted shapes with experimental observations. Through these predictions, vesicle and SDE transformation phase diagrams are developed and, importantly, in the SDE case, shape boundaries are proposed for the first time relating RBC shape categories to RBC reduced volume and reduced MAD.