Characteristics Of Microcirculation Research Articles

Genetic Algorithms for Feature Selection in the Classification of COVID-19 Patients.

Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2) infection can cause feared consequences, such as affecting microcirculatory activity. The combined use of HRV analysis, genetic algorithms, and machine learning classifiers can be helpful in better understanding the characteristics of microcirculation that are mainly affected by COVID-19 infection. This study aimed to verify the presence of microcirculation alterations in patients with COVID-19 infection, performing Heart Rate Variability (HRV) parameters analysis extracted from PhotoPlethysmoGraphy (PPG) signals. The dataset included 97 subjects divided into two groups: healthy (50 subjects) and patients affected by mild-severity COVID-19 (47 subjects). A total of 26 parameters were extracted by the HRV analysis and were investigated using genetic algorithms with three different subject selection methods and five different machine learning classifiers. Three parameters: meanRR, alpha1, and sd2/sd1 were considered significant, combining the results obtained by the genetic algorithm. Finally, machine learning classifications were performed by training classifiers with only those three features. The best result was achieved by the binary Decision Tree classifier, achieving accuracy of 82%, specificity (or precision) of 86%, and sensitivity of 79%. The study's results highlight the ability to use HRV parameters extraction from PPG signals, combined with genetic algorithms and machine learning classifiers, to determine which features are most helpful in discriminating between healthy and mild-severity COVID-19-affected subjects.

“Holiday heart” syndrome in rats: Features of microcirculation, functional state and anatomy of the heart

“Holiday heart” syndrome in rats: Features of microcirculation, functional state and anatomy of the heart

Dynamic Microcirculation Characteristics of Plantar Skin Under Metatarsal Head of Human Foot in Response to Life-Like Pressure Stimulus.

Diabetic foot ulcer (DFU) is a severe complication with high mortality. High plantar pressure and poor microcirculation are considered main causes of DFU. The specific aims were to provide a novel technique for real-time measurement of plantar skin blood flow (SBF) under walking-like pressure stimulus and delineate the first plantar metatarsal head dynamic microcirculation characteristics because of life-like loading conditions in healthy individuals. Twenty young healthy participants (14 male and 6 female) were recruited. The baseline (i.e., unloaded) SBF of soft tissue under the first metatarsal head were measured using laser Doppler flowmetry (LDF). A custom-made machine was utilized to replicate daily walking pressure exertion for 5 min. The exerted plantar force was adjusted from 10 N (127.3 kPa) to 40 N (509.3 kPa) at an increase of 5 N (63.7 kPa). Real-time SBF was acquired using the LDF. After each pressure exertion, postload SBF was measured for comparative purposes. Statistical analysis was performed using the R software. All levels of immediate-load and postload SBF increased significantly compared with baseline values. As the exerted load increased, the postload and immediate-load SBF tended to increase until the exerted load reached 35 N (445.6 kPa). However, in immediate-load data, the increasing trend tended to level off as the exerted pressure increased from 15 N (191.0 kPa) to 25 N (318.3 kPa). For postload and immediate-load SBF, they both peaked at 35 N (445.6 kPa). However, when the exerted force exceeds 35 N (445.6 kPa), both the immediate-load and postload SBF values started to decrease. Our study offered a novel real-time plantar soft tissue microcirculation measurement technique under dynamic conditions. For the first metatarsal head of healthy people, 20 N (254.6 kPa)-plantar pressure has a fair microcirculation stimulus compared with higher pressure. There might be a pressure threshold at 35 N (445.6 kPa) for the first metatarsal head, and soft tissue microcirculation may decrease when local pressure exceeds it.

Magnetic field application in bone tissue regeneration: issue current status and prospects for method development

Relevance. Magnets have long been used to treat various diseases, especially in inflammatory processes. According to existing historical data, magnetotherapy was already used in ancient times by the Chinese, Egyptians and Greeks. Different magnetic field strengths affect cells in different ways, with medium-strength magnetic fields being the most widely used. The review presents a brief history and current state of the issue of using a magnetic field in bone tissue regeneration. Modern knowledge about the mechanisms of physiological and reparative regeneration, restoration of bone tissue is clarified, and modern areas of bone tissue engineering are considered, taking into account the characteristics of microcirculation and the effect of a magnetic field on the physiology of bone tissue and reparative regeneration. One of the key findings of the review is that the magnetic field improves bone tissue repair by influencing the metabolic behavior of cells. Studies show that magnetotherapy promotes the activation of cellular processes, accelerates the formation of new bone tissue and improves its quality. It is also noted that the magnetic field has a positive effect on microcirculation, improving the blood supply to tissues and facilitating a better supply of nutrients to the site of injury. This contributes to faster wound healing and early rehabilitation of patients. Conclusion. Magnetotherapy is one of the effective physical and rehabilitation methods of treatment that will become increasingly important in modern medicine. However, further research is needed to better understand the mechanisms of action of a magnetic field on bone tissue and to determine the optimal parameters for its application.

Photoplethysmography for Assessing Microcirculation in Hypertensive Patients After Taking Antihypertensive Drugs: A Review.

High blood pressure (BP) is a common disease and is associated with many chronic diseases. Measuring BP is essential for the treatment and management of many diseases, and therefore there is a growing need for a non-invasive, sleeveless and continuous BP monitoring device. With the development of technology, pulse waveform analysis using photoplethysmography (PPG) has become more feasible for evaluating BP. This study aimed to evaluate the changes of vascular elasticity and blood volume over time by using the characteristic parameters extracted by PPG. We reviewed the latest progress and literature on the observation of capillary network characteristics in hypertensive and non-hypertensive patients by PPG, the influence of different drugs on microcirculation characteristics in hypertensive patients with PPG, and further explored the key relationship between microcirculation and hypertension. We found that the PPG waveform produced by the fingertips of hypertensive patients is very different from that of healthy people, and the PPG waveform changes significantly during diastolic period after antihypertensive treatment. With the rapid development of medical technology, people can get more intuitive microcirculation image data, which provides beneficial help for the comprehensive understanding of hypertension.

Cerebral Microstructural and Microvascular Changes in Non-Neuropsychiatric Systemic Lupus Erythematosus: A Study Using Diffusion Kurtosis Imaging and 3D Pseudo-Continuous Arterial Spin Labeling.

The purpose of this study was to observe cerebral microstructure and microcirculation features, as well as changes in white matter (WM) and gray matter (GM) among patients with non-neuropsychiatric systemic lupus erythematosus (non-NPSLE). We compared 36 female patients with non-NPSLE and 20 age- and gender-matched healthy controls (HCs) who underwent 3.0T MRI imaging with diffusion kurtosis imaging (DKI) and 3D pseudo-continuous Arterial Spin Labeling (pCASL). Mean kurtosis (MK), mean kurtosis tensor (MKT), and cerebral blood flow (CBF) values were obtained from 25 brain regions, including WM and GM. We analyzed the correlation between imaging indicators and clinical data. When compared with HCs, patients with non-NPSLE had reduced MK and MKT values in regional WM, deep GM, and the left frontal lobe cortical GM, and increased CBF in the right parietal lobe WM and right semioval center (SOC). The MK and MKT values were weakly correlated with CBF in some regions, including WM and GM. Complement 3 (C3) and Complement 4 (C4) showed a weak positive correlation with MK and MKT in some regions, including WM and deep GM, while platelet (PLT) was positively correlated with MKT in the left frontal lobe WM; dsDNA antibody was correlated negatively with MK in the right occipital lobe WM; and erythrocyte sedimentation rate (ESR) was correlated negatively with CBF in the left SOC. Our findings revealed the presence of brain microstructural and microvascular abnormalities in non-NPSLE patients, indicating microstructural damage in the cortical GM, which was less commonly reported. We found DKI and pCASL useful in detecting early brain lesions, and MK was a more sensitive and beneficial indicator.

Оценка микроциркуляции по данным ОКТ-А при диабетической ретинопатии

Diabetic retinopathy (DR) is a common complication of diabetes mellitus (DM) and the leading cause of blindness worldwide. The purpose of the study was to determine the characteristics of microcirculation in patients with type 2 diabetes without clinical signs of retinopathy in the fundus and at different stages of DR using the OCT-A method. As a result of the studies, an increase in the area of the FAZ with the progression of the severity of the disease, as well as a decrease in the density of parafoveal superficial and deep vessels at different stages of DR, was revealed. In the deep plexus, the decrease in vascular density occurred earlier, manifesting in patients with type 2 diabetes without DR, compared with the superficial plexus, where it began with moderate to severe NPDR and was more pronounced in PDR. Thus, a decrease in the density of the capillary network of the deep vascular plexus, which are detected even at the preclinical stages of the development of DR and increase as the disease progresses. can serve as a marker of disease severity in the early stages of diabetic retinopathy. Keywords: diabetic retinopathy, microcirculation, optical coherence tomography-angiography

Inner retinal layers' alterations of the microvasculature in early stages of Parkinson's disease: a cross sectional study.

To investigate microcirculation characteristics of the inner retinal layers at the macula and the peripapillary area using Optical Coherence Tomography Angiography (OCT-A) of patients in early stages of Parkinson's disease (PD). 32 PD patients and 46 age- and gender-matched healthy controls were included in this cross sectional study. OCT-A imaging was performed to analyze microcirculation characteristics at each separate macular region (fovea, parafovea, and perifovea) and the peripapillary area of the inner retinal layers. Individuals with PD had significantly lower parafoveal, perifoveal and total vessel density (VD) in the superficial capillary plexus (SCP) than controls (all p < 0.001), while foveal VD was higher in PD eyes than that of controls, though not statistically significant. Similarly, individuals with PD had significantly lower parafoveal, perifoveal and total perfusion in the SCP than control eyes (all p < 0.001), while foveal perfusion was significantly higher in PD eyes than that of controls (p = 0.008). PD eyes had significantly smaller FAZ area and perimeter accompanied by decreased circularity at the SCP as compared to controls (all p < 0.001). Concerning the peripapillary area, individuals with PD had significantly lower radial peripapillary capillary perfusion density and flux index at the SCP than controls (all p < 0.001). All p values remained statistically significant even after using the Bonferroni correction for multiple comparisons, except for that of foveal perfusion. Our study indicates alterations of the inner retinal layers at the macula and the peripapillary area at the preliminary stages of PD. OCT-A parameters could potentially comprise imaging biomarkers for PD screening and improve the diagnostic algorithms.

State of microcirculation in the retina and choroid according to optical coherence tomography with angiography data in children with posterior and panuveitis

AIM: Retinal and choroidal microvascular changes analysis in children with posterior and panuveitis using optical coherence tomography with angiography (OCTA) and determination of the possibility of using this method in activity assessment and disease monitoring.&#x0D; MATERIAL AND METHODS: 24 children with uveitis were examined. The age of children was from 8 to 18 years old (38 affected eyes). All included patients were divided into two groups: with posterior uveitis (27 eyes) and with panuveitis (11 eyes). In each of the groups, subgroups with active and inactive uveitis were identified. In addition to the standard examination OCTA was performed. Foveal avascular zone (FAZ) area, perfusion density in the superficial and deep vascular plexuses of the retina (SVRP, DVRP) and also in the layers of choriocapillaries and large and medium vessels of the choroid were studied. The control group consisted of 10 paired healthy eyes.&#x0D; RESULTS: Аll eyes with posterior and panuveitis were characterized by the irreversible decrease in perfusion density in DVRP. In eyes with active chorioretinitis was also detected the reversible decrease in perfusion density in SVRP, layers of choriocapillaries and large and medium vessels of the choroid. The formation of choroidal neovascular membranes (CNM) in patients with panuveitis with choroiditis was accompanied by the decrease in perfusion density at all levels studied. In eyes with chorioretinitis and CNM the decrease in perfusion density was detected in DVRP and the area of FAZ increased.&#x0D; CONCLUSION: The features of microcirculation in the chorioretinal complex identified using OCTA in children with posterior and panuveitis can improve the diagnosis and monitoring of these diseases.

Effect of silicone oil on retinal microcirculation after vitrectomy for rhegmatogenous retinal detachment evaluated by OCT angiography: a literature review.

Silicone oil (SO) has been widely used as intravitreal tamponade agent for rhegmatogenous retinal detachment (RRD) and has been occasionally associated with incomplete retinal structural and functional recovery. The use of Optical Coherence Tomography Angiography (OCT-A) has recently attracted significant attention for detailed analysis of retinal capillary plexus and blood flow changes as predicting factors for postoperative outcomes. A detailed literature search was performed in PubMed database until October 2022. The following keywords were used: rhegmatogenous retinal detachment, silicone oil, optical coherence tomography angiography, macular microvasculature, peripapillary capillary plexus, vessel density, and foveal avascular zone. We identified and reviewed 19 studies referring to microcirculation alterations of the retinal capillary plexus as seen on OCT-A in eyes treated by vitrectomy with intravitreal SO for RRD. A comprehensive update revealed variability of microcirculation characteristics of the retinal capillary plexus including the macular and the peripapillary capillaries. Further studies are warranted to clarify the OCT-A values in an attempt to identify the potential effect of SO on retinal tissue in clinical practice. A review of the existing literature sheds light on the effect of SO on retinal capillary plexus and the potential impact on functional outcomes after vitrectomy for RRD. This article discusses important aspects of key publications on the topic, highlights the importance to identify distinct alterations of the microvasculature status, and proposes the need for further future research in this field.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-COVID Syndrome: A Common Neuroimmune Ground?

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating chronic disease of unknown etiology, sharing a similar clinical presentation with the increasingly recognized post-COVID syndrome. We performed the first cross-sectional study of ME/CFS in a community population in Russia. Then we described and compared some clinical and pathophysiological characteristics of ME/CFS and post-COVID syndrome as neuroimmune disorders. Of the cohort of 76 individuals who suggested themselves as suffering from ME/CFS, 56 were diagnosed with ME/CFS by clinicians according to ≥1 of the four most commonly used case definitions. Of the cohort of 14 individuals with post-COVID-19 syndrome, 14 met the diagnostic criteria for ME/CFS. The severity of anxiety/depressive symptoms did not correlate with the severity of fatigue either in ME/CFS or in post-COVID ME/CFS. Still, a positive correlation was found between the severity of fatigue and 20 other symptoms of ME/CFS related to the domains of "post-exertional exhaustion", "immune dysfunction", "sleep disturbances", "dysfunction of the autonomic nervous system", "neurological sensory/motor disorders" and "pain syndromes". Immunological abnormalities were identified in 12/12 patients with ME/CFS according to the results of laboratory testing. The prevalence of postural orthostatic tachycardia assessed in the active orthostatic test amounted to 37.5% in ME/CFS and 75.0% in post-COVID ME/CFS (the latter was higher than in healthy controls, p = 0.02). There was a more pronounced increase in heart rate starting from the 6th minute of the test in post-COVID ME/CFS compared with the control group. Assessment of the functional characteristics of microcirculation by laser doppler flowmetry revealed obvious and very similar changes in ME/CFS and post-COVID ME/CFS compared to the healthy controls. The identified laser doppler flowmetry pattern corresponded to the hyperemic form of microcirculation disorders usually observed in acute inflammatory response or in case of systemic vasoconstriction failure.

Effects of Fluids on the Sublingual Microcirculation in Sepsis.

Sepsis is one of the most common and deadly syndromes faced in Intensive Care settings globally. Recent advances in bedside imaging have defined the changes in the microcirculation in sepsis. One of the most advocated interventions for sepsis is fluid therapy. Whether or not fluid bolus affects the microcirculation in sepsis has not been fully addressed in the literature. This systematic review of the evidence aims to collate studies examining the microcirculatory outcomes after a fluid bolus in patients with sepsis. We will assimilate the evidence for using handheld intra vital microscopes to guide fluid resuscitation and the effect of fluid bolus on the sublingual microcirculation in patients with sepsis and septic shock. We conducted a systematic search of Embase, CENTRAL and Medline (PubMed) using combinations of the terms "microcirculation" AND "fluid" OR "fluid resuscitation" OR "fluid bolus" AND "sepsis" OR "septic shock". We found 3376 potentially relevant studies. Fifteen studies published between 2007 and 2021 fulfilled eligibility criteria to be included in analysis. The total number of participants was 813; we included six randomized controlled trials and nine non-randomized, prospective observational studies. Ninety percent used Sidestream Dark Field microscopy to examine the microcirculation and 50% used Hydroxyethyl Starch as their resuscitation fluid. There were no clear effects of fluid on the microcirculation parameters. There was too much heterogeneity between studies and methodology to perform meta-analysis. Studies identified heterogeneity of affect in the sepsis population, which could mean that current clinical classifications were not able to identify different microcirculation characteristics. Use of microcirculation as a clinical endpoint in sepsis could help to define sepsis phenotypes. More research into the effects of different resuscitation fluids on the microcirculation is needed.

Ephedrine vs. phenylephrine effect on sublingual microcirculation in elderly patients undergoing laparoscopic rectal cancer surgery.

BackgroundThe effects of anesthesia administration on sublingual microcirculation are unknown. It is unclear how sublingual microcirculation responds to ephedrine or phenylephrine administration. We hypothesized that microvascular perfusion is impaired under anesthesia.Materials and methodsWe randomly divided 100 elderly patients undergoing laparoscopic rectal cancer surgery into phenylephrine and ephedrine groups in a 1:1 ratio. Ephedrine or phenylephrine was administered when MAP was < 80% for > 1 min. The heart rate (HR) and mean arterial pressure (MAP) were recorded every 5 min. Lactic acid was tested both pre- and postoperatively. The sublingual microcirculation characteristics of the microvascular flow index, the percentage of perfused vessels, the density of perfused vessels, and the heterogeneity index were monitored using a sidestream dark field imaging device.ResultsTheir MAP showed an evident decrease of > 20%. At this point, the HR, microvascular flow index, perfused vessel density, and proportion of perfused vessels decreased similarly in ephedrine and phenylephrine groups. Conversely, the heterogeneity index increased in both groups. After phenylephrine and ephedrine administration, ephedrine treatment significantly increased the proportion of perfused vessels, microvascular flow index, and HR compared with phenylephrine treatment.ConclusionGeneral anesthesia was associated with reduced MAP, HR, and sublingual microcirculation in elderly patients undergoing laparoscopic rectal cancer surgery. The results of ephedrine treatment were better than those of phenylephrine treatment in terms of HR, increased the proportion of perfused vessels, and microvascular flow index of sublingual microcirculation.Clinical trial registration[www.ClinicalTrials.gov], identifier [ChiCTR-2000035959].

THE COMPLEX STUDY OF GINGIVAL MICROVESSELS IN YOUNG PEOPLE

Morphological and functional features of tissue blood flow are genetically determined, the identification of individual characteristics of microcirculation in the oral mucosa in the gum area can help determine the specifics of periodontal tissue damage in various patients. The aim of the study was to study tissue blood flow and microvessels in different areas of the oral mucosa in young people. In 40 healthy young people, biomicroscopy and laser Doppler flowmetry were used to record blood microcirculation indicators in various parts of the gums in the upper and lower jaws. On cadaveric material, the depth of blood vessels in different parts of the gum was studied. As a result of the study, it was found that the density of microvessels and the intensity of blood flow decrease with distance from the transitional fold to the edge of the gum. In the same areas of the mucous membrane in the upper and lower jaws, the microcirculation indicators do not differ. The most common (in 35 out of 40 subjects) in the vessels of the oral mucosa was the mesoemic type of blood microcirculation, in which the tissue blood flow was of medium intensity and the mechanisms of its regulation were balanced. In other cases, very low (hypoemic type) or high (hyperemic type) indicators of tissue blood flow with weak activity of vasomotor mechanisms of regulation of the state of microvessels of the oral mucosa were recorded. Thus, the use of a set of methods for studying the microvasculature of the oral mucosa in the gingival region allows us to quantitatively characterize the state of microvessels, as well as the intensity of tissue blood flow in different parts of the gingiva of the upper and lower jaws in young people. The richest microvascular network is observed in the region of the transitional gingival fold. As the distance from the transitional fold to the marginal part of the gums, the density of capillaries and the intensity of blood flow in them decrease, the gingival mucosa near the neck of the tooth has the lowest microcirculation rates.

Retinal microcirculation characteristics in obstructive sleep apnea/hypopnea syndrome evaluated by OCT-angiography: a literature review.

The retina may provide a window to estimate systemic vascular status; therefore, there has been interest in identifying microcirculation characteristics that possibly reflect hypoxic alterations in obstructive sleep apnea/hypopnea syndrome (OSAS). Emerging evidence has suggested that retinal microvasculature investigation holds the potential to characterize the pathophysiology involved in ocular manifestations of OSAS. The advent of optical coherence tomography angiography (OCT-A) has attracted significant attention as this technique offers detailed analysis of the retinal capillary plexus. A detailed literature search was performed in PubMed database until December 2021. We identified and reviewed all papers referring to the alterations of the retinal capillary plexus in OSAS using OCT-A. A comprehensive update indicates that microcirculation alterations of the retinal capillary plexus utilizing OCT-A may differ with severity of OSAS and imply the potential underlying pathophysiology of ocular manifestations. The reviewed series have revealed variability concerning microvasculature characteristics at the macular and the peripapillary area. Further studies are warranted to establish the OCT-A parameters as biomarkers regarding the evaluation of OSAS in clinical practice. Retinal capillary plexus characteristics as seen on OCT-A reflect microvasculature alterations, potentially leading to concomitant ocular comorbidity in the context of OSAS. The reviewed literature may confirm the diagnostic and prognostic value of OCT-A in the assessment of the pathophysiology of ocular manifestations in OSAS and highlight unmet needs to be addressed by future research.

Features of microcirculation and metabolism in the skin and soft tissues of the injured area in experimental explosive trauma

Time, nature, and duration of changes in microcirculation and metabolism, as well as their differences in skin and muscle tissue of the injured area during experimental explosive trauma in rats in different wound process phases, are evaluated. Experimental explosive damage was simulated on 30 Wistar rats. The total condition of rats, their activity, interest in food and water, wound area with characteristic wound healing time calculation, the volume of injured pelvic limb, and changes of microcirculation and metabolism in the skin and skeletal muscles of the paravulnar region were evaluated. The explosive damage has led to a deterioration of microcirculation and metabolism in the skin, and especially, in the muscles of the injured area. Compared to the intact group, the microcirculation deterioration resulted in a decreased constant component of perfusion in the skin and muscles by 57.6% and 40.9% and a decreased vial by 76.9% and 76.5%, respectively (p 0.05), as well as in reducing the fluorescent oxygen intake in the skin and muscles by 25.7% and 51.8% and a complex indicator of effective oxygen exchange by 81.1% and 91.9%, respectively (p 0.05). During the experiment, the microcirculation and metabolism were gradually restored, which is more pronounced in the skin, except for the repeated deterioration of the non-vascular regulation of microcirculation in the muscle (a decreased vial by 29.3% of the norm, p 0.05). Changes in the main indicators of microcirculation and metabolism indicate normal skin defect healing and unsatisfactory muscle defect repair (decreased volume of the injured limb (68% of the norm, p 0.05)), accompanied by the recurrence of extravascular disorders in the muscle. Developing new and improved existing methods of delivering biologically active drugs and drugs to the area of muscular damage in the early days after the injury, which strengthen the local blood flow and create conditions for damaged muscle regeneration, reduce the wound healing time without forming pathological scars.

Distinction of experimental wounds microcirculation under local immunotherapy

Introduction. Changes in local microcirculation are essential in the treatment of infectious surgical diseases. Aim of the study to evaluate the features of microcirculation while comparing local treatment with aqueous dispersions of oxide nanostructures of metals, myelopide and chlorhexidine bigluconate in experimental conditions on animals.Materials and methods. Experimental modeling was performed on white Wistar rats of both sexes. 6 groups were formed: 1 – withdrawn from the experiment on the 1st day; 2 – control group without treatment; 3 – treatment with an aqueous dispersion of metal oxide nanostructures (group 1); 4 – treatment with a solution of 300 µg of myelopide per 1 ml (group 2); 5 – treatment with a solution of 600 μg of myelopide per 1 ml (group 3); 6. treatment with an aqueous solution of chlorhexidine bigluconate 0.05 % (group 4). The study was carried out on the 1st and 7th days of treatment, determining the number of capillaries per 0.1 mm2 of biopsy specimens. The data were processed with the determination of the mean values (M±m), 1st and 3rd quartiles [Q1-Q3], standard deviation (σ), correlation coefficient (CV, %), coefficient of Student’s.Results. On the first day, the animals had an average of 2.5±0.9 capillaries per 0.1 mm2 of wound area. On the 7th day, the lowest vascularization was in the control group 2.7±0.9 per 0.1 mm2 . The largest number of vessels was determined in the 1st observation group using aqueous dispersions of metal oxide nanostructures. The correlation coefficients were 40–56 %. On the 7th day, the values of neoangiogenesis during local immunocorrection using an aqueous solution of myelopide were similar.Conclusions. The least vascularization was noted in the control group (2.7±0.9). The greatest changes were associated with the use of aqueous dispersions of metal oxide nanostructures (3.8±1.4). The differences in the healing dynamic were associated with neoangiogenesis and the multifactorial nature of local immunocorrection.

Changes in microcirculation and metabolic activity in soft tissue after local injection of hyaluronic acid in different modes in experimental explosive injury

Objective: To identify changes in microcirculation and metabolic activity in soft tissues in an experimental explosive wound after local administration of hyaluronic acid and to determine the mode of its use, in which these changes are sanogenetically significant.Methods: The experiments were approved by the local Ethics Committee and performed on 96 male Wistar rats weighing 300-350 g. at the age from 4 to 4.5 months. The design of the study included the following stages: wound modeling (according to the method which has RF patent for invention No. 2741238); closing the wound with a pressure bandage and fixing it with a patch; primary surgical treatment of the wound 3 hours after the injury; fan (5-6 points) intramuscular injection of hyaluronic acid (“Hyalift” medication) diluted with 0.9% sodium chloride solution to 1.75% (total volume – 0.5-0.8 ml); dynamic observation accompanied by daily wound dressings (chlorhexidine, and Levomekol ointment) until its epithelialization and by intramuscular administration of antibacterial drug (Gentamicin sulfate) during the first 7 days after the injury. The study of microcirculation and metabolism of tissues of the injury zone using laser Doppler flowmetry, optical tissue oximetry and laser fluorescence diagnostics (using the device "Lakk-M") was conducted on the 7th, 14th and 28th day after the injury.Results: Early (3 hours after the injury) local application of HA in case of an explosive soft tissue wound improves the perfusion characteristics of microcirculation, has a positive effect on the trophism and oxidative metabolism of skeletal muscles, and reduces the time of wound healing. The early administration (3 hours after the injury) of HA in the mode: locally in the para volar tissues, after 3 hours (at the end of the primary surgical treatment of the wound) and additionally after 24 hours after the injury is considered to be the most effective.Conclusions: Intramuscular injection of hyaluronic acid into the para volar tissues in the first hours after the wound in case of an explosive soft tissue wound is a sanogenetically justified method of correcting the wound process.

Hypertensive patients features of the microcirculation type after new coronavirus infection of COVID-19

Introduction. The COVID-19 pandemic multiplies the incidence of long-term adverse events. Family history of heart disease predicates the necessity of study hemostasis in hypertensive patients. The purpose was to study the microcirculation in hypertensive COVID-19 survivors. Materials and methods. We selected patients treated at the hospitals of Samara from January to March 2021. COVID-19 survivors (diagnosis was confirmed by polymerase chain reaction analysis) were divided into 2 groups and analysed: the group with family history of hypertension (167 patients) and control group with no relevant past medical history (68 patients). The main microcirculation characteristics were evaluated by laser Doppler flowmetry of skin blood flow. Results. The average age of COVID-19 survivors was 52.3±14.2 years, n=86 (51.4 %) – male. The majority of patients (n=61/36.5 %) were 45 to 54 years. A fifth of the patients (n=35/20.9 %) showed no complaints about the underlying disease, the clinical manifestations of the rest were general weakness, fever, shortness of breath, cough, headaches, unstable blood pressure, inflammation of the ENT organs. By comparison the microcirculation parameters of the case patients and control group, a decreased perfusion was detected. It requires a preventive medicine to prevent from early and distant micro and macrothrombosis. Conclusion. The study of microcirculation essential features by the LDF of skin blood flow revealed a pathological type with a predominance of vasoconstrictions in patients with a history of hypertension. Taking into account the proven increase in the incidence of thrombotic events in COVID-19 survivors, the noticed changes in microcirculation require a new approach to prevent from adverse events concerning the hypercoagulation process, especially in patients with famil y history of heart disease.

STATE OF MICROCIRCULATION AND FREE-RADICAL PROCESSES OF PERIODONTAL TISSUES IN SMOKING DEPENDENT PATIENTS WITH CHRONIC GENERALIZED PERIODONTITIS ASSOCIATED WITH CHRONIC HYPERACID GASTRITIS

The aim: The aim of the work was to determine the state of microcirculation and free radical processes of periodontal tissues in smoking dependent patients with chronic generalized periodontitis associated with chronic hyperacid gastritis. Materials and methods: We examined 90 patients (men and women) aged 25 to 44 years, who were divided into 3 groups: the first group - 48 smoking patients with chronic generalized periodontitis and chronic hyperacid gastritis associated with Helicobacter pylori; the second group - 22 patients with chronic generalized periodontitis and chronic hyperacid gastritis associated with Helicobacter pylori, without the bad habit; the third group - control, consisted of 20 healthy individuals. The smoking patients were randomly divided into two subgroups: patients of the first subgroup (G1.1) received the basic therapy of chronic generalized periodontitis and the proposed treatment and prevention complex; the patients in the second subgroup (G1.2) received basic therapy for chronic generalized periodontitis and ultraphonophoresis with placebo. Results: The use of treatment and prevention complex in smoking dependent patients and patients without the bad habit with chronic generalized periodontitis and chronic hyperacid gastritis associated with Helicobacter pylori demonstrated a positive dynamics of the functional characteristics of microcirculation and the balance in the lipid peroxidation – antioxidant system. Conclusions: So, the use of the proposed treatment and prevention complex had a positive effect on the state of microcirculation and free radical processes of periodontal tissues both at the near and long-term follow up, even under conditions of chronic hyperacid gastritis and the risk factor – smoking.