Pathomorphological Study Research Articles

Minimally invasive methods in pathomorphological assessment with a complete clinical response to neoadjuvant polychemotherapy in breast cancer patients

Purpose of the study. To evaluate and compare the diagnostic significance of vacuum‑ assisted biopsy (VAB) and multifocal trepan biopsy (MTB) methods based on a pathomorphological study of postoperative material in patients diagnosed with breast cancer (BC) in all molecular biological types after neoadjuvant polychemotherapy (NAPCT) with a complete clinical response (cCR). Patients and methods. The study included 70 patients with cT1–3N0–3M0 breast cancer with different molecular biological types after NAPCT. It was conducted at the P. Hertsen Moscow Oncology Research Institute – Branch of the National Medical Research Radiological Centre from 2021 to 2023. All patients underwent ultrasound and digital mammography before andafter NAPСT to assess the clinical response to treatment. MTB was performed in 35 patients, VAB in 35 patients, followed by surgical treatment. Histological findings obtained by VAB and MTB and surgical material were compared to assess the pathomorphological response of the tumor to treatment. Results. According to the pathomorphological conclusion, the following results were obtained during the VAB: 1 – truly positive, 29 – truly negative, 3 – falsely negative, 0 – falsely positive. The overall sensitivity of the technique was 25.0 % (CI 6.8–60.2 %); specificity – 100 % (CI 88.1–100 %); false negative result (presence of tumor cells in the surgical material and negative result of VAB) – 9.1 % (CI 3.4–20.2 %); false positive result (absence of tumor cells in the surgical material and a positive result of VAB) – 0 % (CI 0–10.6 %). The overall diagnostic accuracy of the method was 90.9 % (CI 79.8–96.6 %). According to the pathomorphological study, the following was obtained during the MTB: 1 – true positive, 17 – true negative, 5 – false negative and 0 – false positive results. The overall sensitivity of the technique was 16.7 % (CI: 4.3–45.9 %); specificity – (100.0 % CI: 80.5–99.9 %). The false negative result was 23.8 % (CI: 11.3–41.9 %). The false positive result is 0 %. The overall diagnostic accuracy of the method was 78.3 % (CI: 61.2–89.7 %). Conclusion. The results of the study indicate a higher sensitivity of the VAB method compared to MTB in assessing the pathomorphological response of breast cancer patients after antitumor drug treatment, which shows a vector for conducting large prospective studies of this method.

Doxorubicin Effects on Cognitive Impairment and the Microscopic View of Brain Structures in Rats

The creation of a validated model of the “chemical brain” in laboratory animals is an urgent task, the solution of which will optimize the search for new drugs for the prevention and pharmacological correction of delayed effects of chemotherapy on the central nervous system. The aim of the work has been to assess the effect of doxorubicin after systemic course administration on behavioral reactions and the microscopic view of the cerebral cortex and hippocampus in rats.Doxorubicin was administered intraperitoneally to male rats at doses of 5 and 6 mg/kg, once a week, for 28 days. The behavioral reactions of the animals were assessed, and pathomorphological studies of the cerebral cortex and hippocampus were carried out.Doxorubicin at doses of 5 and 6 mg/kg causes inhibition of motor activity in the “Open Field” test, impairment of non-spatial and spatial memory in the “New Object Recognition” and “Y-Maze” tests, respectively. Doxorubicin at these doses increases the severity of vascular congestion and perivascular edema in the cerebral cortex and hippocampus.Doxorubicin at doses of 5 and 6 mg/kg causes impairment of cognitive functions in rats in tests assessing non-spatial and spatial memory, as well as microcirculation disorders in the cerebral cortex and hippocampus of rats.

Specific Respiratory Toxicity of the Pharmaceutical Substance Articaine Hydrochloride Following Chronic Inhalation Exposure

Introduction: In the Republic of Belarus, no hygienic standards or methods of control in the workplace air have been developed for the group of modern amide local anesthetics, including articaine hydrochloride. Objectives: To study the specific toxic effect of the pharmaceutical substance articaine hydrochloride on the respiratory system, to establish limiting indicators and threshold concentrations for chronic inhalation exposure for subsequent justification of the safe level of the substance in the workplace air of a pharmaceutical facility. Materials and methods: Experimental studies were carried out on 36 outbred albino rats intranasally exposed to various concentrations (2, 10 and 50 mg/m3) of the pharmaceutical substance during 4 months. At the end of the experiment, we collected bronchoalveolar lavage fluid and tested it for cytokine concentrations and cellular structure. The trachea, bronchi and lungs were isolated from euthanized animals for pathomorphological studies. Statistical data processing was performed using parametric and nonparametric tests in Statistica 13 software. Differences between groups were considered significant at p < 0.05. Results: The specific toxic effect of the pharmaceutical substance on the bronchopulmonary system at different levels (2-10-50 mg/m3) of inhalation exposure to articaine hydrochloride was manifested by the maximum development of pathomorphological structural changes at the highest concentration of 50 mg/m3, such as a statistical increase in the thickness of the interalveolar septa of the lungs by 1.85 times, the appearance of pronounced perivascular and peribronchial infiltration in the lungs in more than half of the rats. Changes in the composition of bronchoalveolar lavage were characterized by a significant increase in the cellular inflammatory component and transformation of the cytokine profile. At the exposure of 50 mg/m3, an increase in the content of lymphocytes and neutrophils was noted by 6.09 and 3.4 times, respectively, the appearance of plasma cells and an increase in the concentration of IL-1 and IL-6 by 2.0 and 3.2 times. Conclusions: The dose-dependent morphological, cytological, and functional changes in the respiratory organs and lavage characterize the exposure concentration of 2 mg/m3 as practically ineffective, 10 mg/m3 as threshold, and 50 mg/m3 as effective in terms of the toxic effects under study.

Efficiency and safety of thread implantology in the long term: data from a pathomorphological study

The evolution of methods used in aesthetic medicine includes a transition to less invasive procedures with high safety and minimal recovery time. That is why numerous non-invasive methods for correcting involutive changes in facial skin (thread lifting, hardware techniques) have been studied for effectiveness and safety over the past decades. Such techniques can improve treatment results and avoid or delay surgical intervention.Material and methods. The work involved a pathomorphological study of material taken by biopsy at the sites of thread implantation and surrounding tissues (1 cm indentation) (Nano spring, Excellence Visage, Excellence Visage HA) within 12 months after thread lifting. Paraffin sections with a thickness of 5–7 microns were made from ready-made paraffin blocks and stained with: hematoxylin – eosin; according to the Weigert-Van Gieson method; Sirius Red paint. Using a microscope with a Sony digital photo attachment with a resolution of 12 megapixels, five photographs were taken from each histological specimen.Research results. As a result of a pathomorphological study of a flap of skin and subcutaneous fat with a synthetic thread in the adipose tissue, it was revealed that along the periphery of the studied material there was moderate chronic inflammation (giant cells of the type of foreign body cells, lymphocytes, fibroblasts) and weak fibrosis, as well as a predominance type I collagen in the skin, and type III collagen predominated in subcutaneous fat tissue.

MORPHOLOGICAL JUSTIFICATION OF RETROMUSCULAR ALLOPLASTY IN DIASTASIS OF RECTUS ABDOMINAL MUSCLES

Background. Diastasis of the rectus abdominis muscles weakens the white line and contributes to the occurrence of defects with the formation of white line hernias and umbilical hernias. In our opinion, the study of the morphological features of the anterior and posterior aponeurotic walls of the rectus abdominis will make it possible to justify alloplasty, which will increase the effectiveness of surgical treatment of diastasis of the rectus abdominis. Aim: Justification of retromuscular alloplasty of diastasis recti abdominis by studying the morphological features of the anterior and posterior aponeurotic walls of the sheath of the rectus muscle Materials and methods. A comprehensive pathomorphological study of the anterior and posterior aponeurotic walls of the rectus abdominis muscles was conducted in 34 patients (the main group) with diastasis recti who underwent surgical treatment. The comparison group consisted of 32 patients with gallstone disease without diastasis recti who underwent laparoscopic cholecystectomy. The obtained material was examined using histological, histochemical, immunohistochemical, morphometric, statistic methods. Results. In a comparative analysis of the morphological indicators of the front sheet of the sheath of the rectus abdominis muscle with the corresponding indicators of the back sheet in the main group of patients with diastasis of the rectus abdominis, the specific volume of the vascular-fibrous component was more important, the specific volume of adipose tissue and the specific volume the volume of the cavities was less important. The obtained pathomorphological data emphasizes that the front sheet of the sheath of the rectus abdominis muscle in diastasis is mechanically stronger compared to the back sheet. The posterior aponeurotic sheet of the vagina of the rectus muscle in case of diastasis is more prone to ruptures, which is evidenced by the greater value of the specific volume of the cavities in the posterior sheet. Conclusions. Morphological changes of the aponeurotic leaves of the sheath of the rectus abdominis in patients of the main group with diastasis of the rectus muscles in comparison with the comparison group without diastasis differ significantly in the detected changes, the results of the morphological study of the anterior and posterior aponeurotic walls of the rectus muscle in their diastasis indicate the fact that the back walls are thinner, branched , with a decrease in the vascular-fibrous component compared to the front ones, which justifies the strengthening of the back aponeurotic walls by means of retromuscular alloplasty during the surgical treatment of diastasis.

ЭКСПЕРИМЕНТАЛЬНОЕ ИССЛЕДОВАНИЕ СОСТОЯНИЯ КОЖИ ОБЛАСТИ РТА ЖИВОТНЫХ ПОСЛЕ ВОЗДЕЙСТВИЯ СТОМАТОЛОГИЧЕСКИХ ДИОДНЫХ ФОТОПОЛИМЕРИЗАТОРОВ

Aim of the study: studying the effect of light radiation from dental photopolymerizers on the soft tissues of the mouth area (regio oralis A01.2.01.018). Materials and methods. Experimental studies were carried out on 50 eight months male rats, randomly divided into 4 groups: 3 main (15 animals each), the fourth - control (5 animals). Under Zoletil anesthesia, the incisors of the lower jaw of experimental animals were exposed twice to light (wavelength 395 - 480 nm) from a dental photopolymerization device. Three photopolymerization modes were used: main group No. 1 – diode photopolymerizer with a luminous flux power of 1000 mW/cm2, main group No. 2 – diode photopolymerizer with a luminous flux power of 1400 mW/cm2; main group No. 3 – diode photopolymerizer with a luminous flux power of 3200 mW/cm2. Animals in the control group were not exposed to light radiation from dental photopolymerizers. After one, three and seven days, animals from groups No. 1 – 3, seven days – animals from the control group were subjected to ether anesthesia and removed from the experiment by decapitation. For pathomorphological studies, a fragment of skin from the mouth area was isolated. The material was fixed with a 15% aqueous neutral solution of formalin and embedded in paraffin. Histological sections were stained with hematoxylin and eosin, according to the van Gieson method, and Alcian blue; performed the CHIC reaction. The vascular bed and its elements were studied using the Gabu-Dybanu method. A standardized comparative microscopic study of skin tissue adjacent to the irradiation zone was carried out using the ZEISS Axio Imager A2 hardware and software complex at magnifications of 1:100 and 1:200. A descriptive method was used to evaluate the results obtained. Results. Microscopy of preparations of the skin of the lips of experimental animals allowed us to come to the conclusion that the primary reaction of tissues to the effects of light radiation from photopolymerizers is of the same type and does not depend on their technical characteristics. Hyperkeratosis and acanthosis of the epithelium, congestion of the microvasculature, the presence of edema and diffuse infiltration of the dermis were detected. Quantitative and qualitative changes in mast cells were observed - an increase in the degree of their degranulation and the number of process forms, which is a marker of tissue damage in response to irradiation. The described changes, which in general are pathomorphological signs of acute inflammation, were determined on the first and third days after irradiation. Further dynamics indicated a decrease in the described reactive changes by the third day when using the photopolymerization mode: wavelength 395 – 480 nm, power 1000 mW/cm2, exposure 10 sec. When using the photopolymerization mode: wavelength 395 - 480 nm, power 1400/3200 mW/cm2, exposure 3 seconds - by the seventh day of observation there was a positive dynamics in the relief of pathological processes, but signs of inflammation remained. Conclusion. Experimental data indicate the possible development of negative photochemical reactions in the skin of the lips after exposure to light from dental photopolymerizers during the treatment of patients with pathology of hard dental tissues. The results obtained can be used to substantiate the prevention of pathological processes in the tissues of the perioral area. Further in vitro, in vivo, and clinical studies are needed to determine the optimal irradiation intensity, irradiation time, and other aspects to ensure the safety and effectiveness of light curing agents.

Pathomorphological and gender-age aspects of echinococosis of the liver

Background. Echinococcosis is a chronic parasitic disease that belongs to zooanthropohelminthosis and is characterized by the development of solitary or multiple cystic formations in the liver, lungs, brain and other organs. Today, the incidence is increasing dramatically in non-endemic countries, and the spread of the disease is largely linked to global population migration. Purpose – To analyze the pathomorphological and sex-age characteristics of operated patients with echinococcosis of the liver for the period 2011–2021. Materials and Methods. Medical documentation and autopsy material of all cases of surgical intervention in patients with liver echinococcosis at the pathology department of the State Institution «Zaycev V.T. Institute of general and urgent surgery of the National Academy of Medical Sciences of Ukraine» for the period 2011–2021. Sex-age characteristics of patients with echinococcosis were studied. A pathomorphological study of the postoperative material was carried out, taking into account the size and type of cysts, and the location of their formation. The preparations were stained with hematoxylin and eosin and by the Van Gieson method. Results. During the period 2011–2021, 36 operated patients with echinococcosis were recorded. Liver echinococcosis was mostly detected in men – 52.8% (р ≤ 0.05), the average age of patients was 46.9 ± 3.1 years. Among the operated, the percentage of people under 50 was 69.4%, with a predominance of men (52%). In the case of primary and recurrent echinococcosis of the liver, single cysts were found in most patients, namely in 26 (72.2%) with predominant localization in the right lobe (88.5%). Multiple cysts were found in 10 patients (27.8%); lesions of the right lobe of the liver – 70.0%, left – 10.0%, both lobes – 20.0%. It was established that the average diameter of echinococcal cysts was 13.8 ± 2.5 cm, individual cysts reached 17 cm. The thickness of all layers of the cyst wall was 1.3 ± 0.3 cm. The outer acellular layer of the cyst wall was 0.8 ± 0.1 cm. In most cases (61.1%, p ≤ 0.05), the parasite was alive, as evidenced by the clear, colorless cyst fluid with the presence of single daughter cysts with a diameter of 0.1 to 2 cm, which had the same macro- and microscopic characteristics as the mother cyst structure The color of the entire membrane of the parasite was white-pink. Conclusions. Over a 10-year period, 36 patients operated on for echinococcosis of the liver were recorded, the majority of cases were men (52.8%, p ≤ 0.05). The average age of the patients was 46.9 ± 3.1 years and ranged from 26 to 69 years. Among those operated on, the percentage of people under 50 was 69.4%, with a predominance of males in the gender structure. In the case of primary and recurrent echinococcosis of the liver, single cysts were found in most patients, namely in 26 (72.2%) with predominant localization in the right lobe (88.5%). Multiple cysts were found in 10 patients (27.8%); lesions of the right lobe of the liver – 70.0%, left – 10.0%, both lobes – 20.0%. The average diameter of echinococcal cysts was 13.8 ± 2.5 cm, individual cysts reached 17 cm. The thickness of all layers of the cyst wall was 1.3 ± 0.3 cm. The outer acellular layer of the cyst wall was 0.8 ± 0.1 cm In most cases, the parasite was alive (61.1%, p ≤ 0.05).

Markers and Predictors of Proliferative Vitreoretinopathy in Open Eye Injury in an Experiment

The objective of the study: to analyze characteristics of a standardized model of type B gunshot open global injury (open injury without intraocular foreign body).Methods: The experiment was carried out on 36 rabbits (71 eyes). Simulation of type B gunshot open global injury (GOEI) was accomplished using pump equipment. The complex of modern standard and high­technology diagnostic methods to study characteristics of type B GOEI in the control period was performed. Biomicroscopy, ophthalmoscopy, optical coherence tomography, electroretinography, ultrasound examination, MRI, enzyme multiplied immunoassay to determine vitreous fibronectin, and pathomorphological study of the eye globe were carried out. Non­parametric statistical methods of data analysis were used.Results: The above diagnostic methods being used, the GOEI experimental model characteristics were determined, including proliferative vitreoretinopathy (PVR) i.e.incidence rate and dynamics.Conclusion. High reproducibility (77–100 %) of microlevel signs of type B GOEI experimental model was demonstrated, that evidenced standardization of the developed model. The viability of the use of hyphema and hemophthalmia as the PVR and GOEI predictors was justified on the basis of correlation analysis in experiment. The analysis of proliferative signs being made when using different study methods (pathomorphological, indirect ophthalmoscopy, optical coherence tomography, ultrasound examination and MRI) proved their application as PVR markers possible. The interchangeability of the study methods used for PVR diagnosis was also justified.

Spontaneous tumours indogs: Aclinical and pathomorphological study inKyrgyzstan.

The aim ofthis study isto investigate the correlation between the incidence ofspontaneous tumours ofvarious origins and the localisation indogs with sex, breed, and age factors. Atotal of360tumours with various localisation were studied pathomorphologically. Histopathologic data sets from 360dog tissue samples were processed and statistically examined. Achi-square test ofindependence was conducted toexamine the relationships among the various levels ofthe specified variables. Logistic regression models were employed for dichotomous outcomes toascertain the influence ofcertain explanatory variables onthe tumour types. Characteristic pathomorphological changes observed during examination ofdogs with oncologic diseases were determined. The most common neoplasms were mammary tumours, accounting for 43% ofthe cases. The mammary gland tumours were most common inmongrel dogs (25%), with German Shepherds (17.3%), Poodles, Dachshunds, Central Asian Shepherds (6.7% each), and Rottweilers (5.7%) following. The highest frequency ofthese tumours appeared at8years ofage, predominantly originating from the ductal epithelium, which represented 46.4% ofall the malignant cases.

The effect of nitric oxide supplied to the oxygenator of the cardiopulmonary bypass on the functions and morphology of internal organs: experimental animal study

To evaluate the effect of NO added to the oxygenator during CPB on the liver and kidneys in pigs.Methods. The experiment was conducted on 10 pigs undergoing cardiac surgery using cardiopulmonary bypass (CPB). Animals of the experimental group (CPB-NO; n = 5) received NO with the gas mixture supplied to the oxygenator at 100 ppm. Animals of the control group (CPB-control; n = 5) did not receive NO via the oxygenator. The surgery lasted 4 hours and was followed by 12-hour postoperative monitoring. To assess the liver and kidney injury, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, creatinine, neutrophil gelatinase-associated lipocalin (NGAL) were determined at baseline, at weaning from the CPB, 6 and 12 hours after weaning from the CPB. A pathomorphological study of the liver and kidneys was also performed.Results. A long period of CPB deliberately used in our experiment caused liver injury. In the CPB-control group, an increase in the ALT concentration was found: 43 (34; 44) U/l at baseline to 82 (53; 99) U/l 12 hours after CPB, p < 0.05. AST concentration in the CPB-control group increased from 25 (17; 26) U/l at baseline to 269 (164; 376) U/l 12 hours after CPB (p < 0.05). We found no significant increase in ALT and AST concentrations in the CPB-NO group. There were no significant differences in ALT and AST concentrations between CPB-NO and CPB-control groups at all study time points. In the CPB-control group, an increase in the creatinine level was found from 131 (129; 133) μmol/l at baseline to 273 (241; 306) μmol/l 12 hours after CPB (p < 0.05). We found no significant increase in creatinine levels in the CPB-NO group. Creatinine levels in the CPB-NO group were significantly lower than in the CPB-control group 12 h after weaning from CPB: 183 (168; 196) vs 273 (241; 306) μmol/l (p < 0.008). We found no significant differences between the study groups by the NGAL level. Morphology revealed characteristic alterative changes in tissues, circulatory disorders, and inflammatory infiltration of varying degrees of severity, which in combination is a manifestation of the acute damaging effect of CPB. In the CPB-NO group, the severity of pathological changes, measured in points, was lower than in the CPB-control group, but no statistically significant differences were found.Conclusion. NO added to the oxygenator gas mixture reduces liver and kidney injury during prolonged CPB. Further research is required.

Pathomorphological study of aspiration pneumonia in cattle: A case report

Pathomorphological study of aspiration pneumonia in cattle: A case report

INFLUENCE OF LOPHANTHUS CHINENSIS DRY EXTRACT ON THE MORPHOFUNCTIONAL STATE OF WISTAR RATS THE BRAIN DURING LONG-TERM ALCOHOLIZATION

The study purpose – to evaluate the effect of the Lophanthus chinensis dry extract on the Wistar rats brain morphofunctional state against the back-ground of long-term alcoholization. Material and methods. Alcohol intoxication was induced by long-term administration (6 weeks) of 40% ethanol in rats. Lophanthus chinensis dry ex-tract at a dose of 100 mg/kg was administered from the 3rd week of the experiment. On days 42-45, the animals were tested in an "open field", an el-evated plus maze, and they developed a conditioned passive avoidance reaction. After which a neurons pathomorphological study in the cerebral cor-tex was carried out. Results. It has been established that L. chinensis dry extract exhibits a neuroprotective effect during long-term alcohol intoxication, preventing the de-velopment of structural disorders in the cerebral cortex, thereby reducing anxiety and emotionality in animals, enhancing orientation-exploratory activity and normalizing mnestic functions. Conclusion. L. chinensis dry extract has a neuroprotective effect during long-term alcohol intoxication.

A report on pathomorphological study of pyothorax in a cat

A report on pathomorphological study of pyothorax in a cat

Siderosis of the esophagus

This publication describes a rare clinical case of esophageal siderosis. The patient was found to have flat irregularly shaped superficial scars with areas of hyperpigmentation of the esophageal mucosa in a dark color. It is known from the anamnesis that she has long suffered from iron deficiency anemia and takes iron preparations. A conclusion was made about the defeat of the esophageal mucosa by iron sulfate preparations - esophageal siderosis. The endoscopic conclusion was confirmed by a pathomorphological study - a few cells with brown pigment in the cytoplasm were found in the subepithelial connective tissue - a picture of siderosis

Study of Tildox AVZ effect on rat blood parameters in a subchronic experiment

The purpose of our research was to study the effect of Tildox AVZ on rat blood counts in a subchronic experiment. Tildox is a complex antibiotic in powder form. One gram of drug contains doxycycline hyclate – 100 mg and tylosin tartrate - 100 mg as active ingredients, sodium benzoate and sucrose as auxiliary substances. The experiment lasted 90 days. The study was conducted on 150 Wistar rats (75 males and 75 females). The body weight of the animals was 190-230 g. During the experiment 5 groups of 30 animals (15 males and 15 females) were formed, three of them were experimental groups, one - control and one – intact. Of the 150 rats involved in the experiment after its completion 100 individuals (50 males and 50 females) were killed for pathomorphological studies of internal organs.To identify the ability to recover and the appearance of resistance to toxic effects the remaining 50 animals (5 males and 5 females from each group) were monitored for 28 days after the experiment.An aqueous solution of the test sample of the drug was administered daily intragastrically using an atraumatic metal probe. The drug was administered to the first experimental group at a dose of 70 mg / kg, the second group - 265 mg / kg, the third group - at a dose of 1000 mg / kg of animal body weight. The control group was in equal conditions and received intragastric saline solution. Intact animals served as a reference. It was found that Tildox AVZ administered intragastrically at doses of 265 and 1000 mg / kg 1 time per day for 90 days has an effect on clinical and biochemical blood parameters. The drug administered at a dose of 70 mg / kg does not cause changes in blood parameters. However when examining the blood of rats 28 days after the recovery period there were no significant changes in clinical and biochemical parameters compared with the control and intact groups.From this it can be concluded that all blood changes had a dose-dependent effect and after stopping the use of the drug the body recovered which indicates the reversibility of the caused shifts in the blood picture.

Morphofunctional characteristics of the vessels of the small circle of blood circulation in those who died from severe and extremely severe forms of new coronavirus infection

BACKGROUND: An important feature of COVID-19 is the development of pronounced hypercoagulation with an increased risk of thrombotic damage to the pulmonary vascular bed, mainly the pulmonary arteries. Thrombosis of the pulmonary blood vessels causes a local violation of hemodynamics with the development of hyperemia, edema, which leads to a decrease in ventilation of the lung tissue area and serves as one of the causes of respiratory failure.
 AIM: This study aimed to conduct a morphological and morphometric analysis of the vascular bed of lung tissues in deceased with severe and extremely severe forms of new coronavirus infection who were on inpatient treatment in the period 2020-2022.
 METHODS: A pathomorphologic study of 129 autopsy cases with a confirmed diagnosis of a new coronavirus infection COVID-19 was performed. Morphometric analysis and statistical data processing of the pulmonary vascular system in histologic preparations stained with hematoxylin and eosin stain, orcein stain and Martius Scarlet Blue (MSB) stain was performed. The control group consisted of 14 patients who died of cardiovascular disease with bilateral focal confluent pneumonia.
 RESULTS: It was found that the proportion of thrombosed vessels in the lung tissues of the deceased was 27.6%. In 87.2% of cases, thrombosis develops in small arteries (lumen diameter 30-500 microns) and small veins (lumen diameter 40-500 microns). The vascular-functional indices of Kernogan and Vogenworth were statistically significantly increased in small arteries and small veins of the 4th order (p=0.001), small arteries (p=0.001) and small veins of the 5th order (p=0.014) compared with the control group.
 CONCLUSION: Diffuse involvement of small caliber blood vessels in the pathological process reflects the severity of specific hemocoagulopathic disorders in the lung tissue. Such disorders lead to the development of ventilation-perfusion disorders and entail an increase in right ventricular failure.

Effectiveness of the total neo-adjuvant therapy in rectal cancer treatment. Results of the randomized trial

To ASSESS effectiveness of total neoadjuvant therapy (TNT) for patients with rectal carcinoma.Patients and methods: patients with histologically proven rectal carcinoma were randomly assigned in two groups: in the TNT group after the neoadjuvant CRT 50-54 Gy with capecitabine 3 consolidation courses of XELOX were done, in the CTR group - conventional neoadjuvant CRT 50-54 Gy with capecitabine. At the end of the treatment, effect was assessed by MRI using the mrTRG scale. For patients with a full clinical response, who have refused surgery, «watch&wait» approach was used. For other patients effect of neoadjuvant therapy was evaluated by pathomorphological study using the Ryan scale. The primary endpoint of study was the complete response rate (clinical and pathomorphological). Secondary endpoints of study: frequency and structure of intraoperative and postoperative complications, the rate of grade 3–4 toxicity of radiotherapy and chemotherapy, R0-resection rates. The study was registered on the ClinicalTrials.gov (NCT04747951)RESULTS: between October 2020 and October 2023, 183 patients were enrolled in the randomized study: 91 patients in the TNT group and 92 patients in the CRT group. At median (Q1, Q3) follow-up period 24 (14; 28) months, complete clinical response observed in 23% (14/60) of TNT patients and in 7% (5/71) of THL patients (p=0.008). The pCR rate was 20% (9/45) in the TNT group and 8% (5/66) in the CRT group (p=0.05). The frequency of development of toxic reactions of degree 3-4, the frequency and structure of intra- and postoperative complications, as well as the frequency of R0 resection of the group did not differ statistically significantly. The total rate of Grade 3–4 toxicity, rate of intra- and postoperative complications, R0-resections rate did not differ between two groups.CONCLUSION: preliminary results of a randomized study demonstrated the effectiveness and safety of total neo-adjuvant therapy in rectal cancer treatment.

Postinfectious epilepsy: clinical and diagnostical features

Background. According to some authors, neuroinfection agents play a role in the development of several neurological disorders, including epilepsy. For many years, it was believed that acute infectious diseases, such as tick-borne encephalitis virus and meningococcus played a leading role in the emerging epileptic process of postinfectious etiology. Regarding a role for chronically persistent infections, it has not been fully explored.Objective: to identify clinical, diagnostic, and morphological features of locally induced postinfectious epilepsy, both at disease onset upon emergence of the first epileptic seizures during acute infectious process and during their recurrence in a chronically persistent infection.Material and methods. The study included observations of 1500 patients with locally induced epilepsy admitted and treated from 2007 to 2017 in various medical inpatient and outpatient institutions. Post-infection locally induced epilepsy with clear causality link between previous neuroinfection and onset of epileptic seizure was found in 127 patients (Group 1). During initial visits, infectious agents in a cohort of patients with recurrent epileptic seizures manifested as chronic persistent infection were suspected in more than 1/3 of the 1373 subjects who sought medical aid comprising 550 people (Group 2). In addition to the clinical evaluation of patients, instrumental studies were performed, including routine electroencephalography (EEG), sleep video-EEG monitoring, magnetic resonance imaging (MRI), and some patients underwent pathomorphological examination using electron microscopy and histological techniques.Results. Gross and marked diffuse disturbances in brain bioelectrical activity were most often detected (58% and 31%, respectively) during video-EEG monitoring in Group 1, whereas moderate alterations were recorded less frequently (11% of observations). In Group 2, the majority of diffuse disturbances in brain bioelectrical activity were of moderate level (79%) followed by mild and irritative changes recorded less frequently (in 21% of cases). MRI data showed that disorders of the amygdala-hippocampal system were observed in 41 (32%) and 211 (38%) patients in Groups 1 and 2, respectively. Histological and electron microscopic data revealed a number of morphological disorders in patients with locally induced postinfectious epilepsy common with earlier described mitochondrial encephalomyopathies (mitochondrial megaconia and pleioconia) as well as a set of specific manifestations typical to such pathology.Conclusion. The conducted clinical, neurophysiological, neuroimaging, and pathomorphological studies of postinfectious epilepsy revealed specific features underlying its development at different stages, from its onset in acute infectious process to chronization in persistent infection. It was found that a comprehensive analysis of the presence and impact of infectious agents in patients with epileptic seizures is important for course and prognosis of postinfectious epilepsy, which is relevant for timely diagnosis and development of specific pharmacotherapy.

Current state of juvenile roach (Rutilus rutilus caspicus)

Fluctuations in water temperature in the Northern Caspian Sea, especially in the shallow zone, are mainly due to fluctuations in air temperature and during the trawling period, in the fall, the water temperature at observation stations showed a decrease in water temperature, which caused the formation of dense aggregations in juvenile roach. To study the nutritional status of juvenile fish living in the Kazakh part of the Caspian Sea, material was selected from different depths of the sea from trawl catches during comprehensive research in the fall of 2022. In the course of studies conducted to assess nutrition using quantitative and qualitative indicators, it was determined that the nutritional spectrum of juvenile roach in the water Caspian Sea is represented mainly by the same bottom organisms with a dominance of crustaceans, with their preference for bivalves, which give a good growth rate. A parasitological study of juvenile roach showed the absence of pathogen circulation in the ecosystem of this reservoir. Based on the results of pathomorphological studies of fish gills, it was found that fragmentary hyperplasia is caused by the presence of protozoal invasion rather than by the influence of environmental factors.

Isolated and combined pneumocystosis of the pulmonary in patients with HIV infection according to the results of pathomorphological study

The most common opportunistic disease in patients with HIV infection is Pneumocystis pneumonia, diagnosis of which is not difficult, and treatment significantly reduces the risk of death. Purpose of the study. To analyze the results of a pathomorphological study of the lungs with isolated pneumocystis and in combination with other lung diseases (bacterial, cytomegalovirus pneumonia and pulmonary tuberculosis) in patients with HIV infection. Materials and methods of research. The results of pathomorphological studies of patients with HIV infection (n=141), who were previously observed in hospitals in the region: patients with pneumocystis pneumonia (n=24), with pneumocystis pneumonia and bacterial pneumonia (n=52), with pneumocystis pneumonia and pulmonary tuberculosis (n=56), with pneumocystis and cytomegalovirus pneumonia (n=9). Results. At the time of death, 72.7% of patients with HIV infection had a viral load level of more than 300000, and 83.7% had a CD4+ lymphocyte level of less than 41 cells/μl. In all patients, treatment with trimethoprim/sulfamethoxazole was started too late. A pathological examination of patients with HIV infection and isolated Pneumocystis pneumonia revealed changes characteristic of this disease. Nosocomial microorganisms were identified in patients with pneumocystosis and bacterial pneumonia. At autopsy in patients with HIV infection with Pneumocystis pneumonia and pulmonary tuberculosis, the picture of tuberculosis was varied, heterogeneous and significantly different from classic granulomatous inflammation. With combined damage to the lungs by pneumocystis and cytomegalovirus, foamy, vacuole-like granular masses (PCS-positive), accumulations of neutrophilic leukocytes were observed in the lumens of the alveoli, and single cells of the “owl’s eye” type were detected. Conclusion. A pathological autopsy confirmed mixed infection in patients with HIV infection.