Characteristics Of Microcirculation Research Articles

Features of microcirculation in psoriatic arthritis

The literature review presents data on features of microcirculation in patients with psoriatic arthritis (PsA). The immune inflammation underlying PsA leads to increased permeability of the vascular wall, deposition of the immune complexes in it, a decreased capillary blood flow, and vascular sensitivity to sympathetic stimulation. In combination with impaired blood rheology during inflammation, these changes have a significant effect on the state of the microvasculature. Increased vascular permeability and a damaged connection between the endothelium and the extracellular matrix in PsA cause the formation of the capillaries with a pathological structure. Microscopic examination of the synovial membrane of patients with PsA shows vascular tortuosity, branching, and elongation. The duration, activity of articular inflammation, as well as severity of psoriasis are associated with the degree of microcirculatory disorders in PsA. The pathomorphological changes in the vessels of patients with PsA are detected not only in the articular tissues but also in the skin, which indicates dysregulation of angiogenesis in general. The mechanisms of the formation of new vessels with a pathological structure are not fully understood. However, most likely, an imbalance of the factors of angiogenesis and antiangiogenesis plays an important role. There is growing evidence that vascular endothelial growth factor (VEGF), transforming growth factor-beta (TGF-beta) and platelet growth factor (PDGF) are involved in the pathogenesis of PsA. At the moment, the issue of early diagnosis of PsA remains relevant, especially in cases with minor skin changes and rheumatoid-like joint lesions. Information on microcirculation obtained by capillaroscopy, video capillaroscopy, and fluorescence microscopy provides additional opportunities for a differential diagnosis of PsA, a determination of activity, and a prognosis of the disease.

Analysis of microcirculatory disorders in men with more than 10 years’ experience on night work

Aim. To study the nature and extent of the effects of long-term sleep and wake phase disorders (working at night for more than 10 years) on the characteristics of microcirculation in men.
 Methods. Laser Doppler flowmetry and spectophotometry, optical tissue oximetry, and laser-induced fluorescence spectroscopy were performed in 34 male patients with a mean age of 40.30.9 years and more than 10 years experience of night work to assess the effectiveness of microcirculation. 25 men with a mean age of 40.21.2 without night work experience were used as a control group. Microcirculation was studied on the laser diagnostic complex LAKK-M (LAZMA, Russian Federation). The measurement was carried out on the skin of the palmar surface of the terminal phalanx of the second finger of the hand. The following indicators were analyzed in automatic mode: the mean perfusion value, the index of specific oxygen consumption in the tissue, capillary blood saturation, the relative volume of the red blood cell fraction, arterial blood oxygen saturation, the index of perfusion oxygen saturation in the microcirculation, the efficiency of oxygen exchange and the fluorescent indicator of oxygen consumption. Statistical processing of the results was carried out using the Student's t-test for independent samples.
 Results. In patients working at night for more than 10 years, a decrease in microcirculation efficiency was revealed. The index of specific oxygen consumption in the tissue was lower than that of healthy volunteers by 34.1% (p=0.000255), and the index of oxygen exchange efficiency by 56.3% (p 0.001). Long-term night work (10 years) can lead to violations of microcirculation parameters and an irreversible decrease in the efficiency of oxygen exchange compared with the control group by an average of 56.3% (18.00.5 for the group with night work experience, 41.20.6 for the group of healthy volunteers, p 0.001), the index of specific oxygen consumption in the tissue by an average of 34.1% (1.530.03 for the group with night work experience, 2.320.2 for the group of healthy volunteers, p=0.000255) and an increase in the index of perfusion oxygen saturation in the microcirculation by 2 times compared with the control group (6.20.05 for the group with night work experience, 3.670.09 for the group of healthy volunteers, p 0.001), which is accompanied by an increase in the saturation of mixed (and venous) blood.
 Conclusion. The nature of the revealed violations of microcirculatory parameters in the long-term night work suggests their significance in the development of diseases that are currently attributable to the so-called group of diseases of civilization.

Study on the characteristics of microcirculation in the site of pressure ulcer in patients with spinal cord injury.

To investigate the characteristics of pressure ulcer microcirculation in SCI patients with pressure ulcer, and to provide evidence for the treatment of pressure ulcer in patients with SCI. Group 1 (n = 12) SCI patients with pressure ulcer, 23 pressure ulcers were included. Group 2 (n = 15) SCI patients without pressure ulcer and the control group (n = 16) healthy adults. The application of laser Doppler perfusion imaging system (Moor FLPI) detector to the microcirculation perfusion of the sacrum area of the control group, the observation group 2 and the pressure ulcer site of the observation group 1, record the microcirculation perfusion (PU), The data of microcirculation perfusion (PU) were compared and analyzed. The correlation between microcirculation perfusion and healing time of pressure ulcer was analyzed. (1) The microcirculation perfusion was highest in the pressure ulcer center. (2) SCI patients and healthy adults had no significant difference of microcirculation perfusion at sacrococcygeal skin. (3) The lower the microcirculation perfusion of the pressure ulcer center, the longer the healing time of pressure ulcer. The healing time and the microcirculation perfusion of pressure ulcer center was negatively correlated. Microcirculation perfusion detection is a noninvasive and effective method for the determination of the scope of pressure ulcer, detection and direction judgment of pressure ulcer sinus tract, monitoring and guidance of pressure ulcer treatment, and prediction of the healing time of pressure ulcer.

Characteristics of circulation and microcirculation in healthy people of Han nationality at different altitudes

Objective: To observe the circulation and microcirculation characteristics of healthy han people in Qinghai at different Guoluo (4 100 m) and Huzhu (2 600 m) and in Shanghai in plain area (4 m). Methods: The 28 healthy han people aged (45.62±10.15) from Guoluo in Qinghai, 27 healthy han people aged (47.25±8.43) from Huzhu in Qinghai and 20 healthy han people aged (43.12±8.28) from Shanghai were divided into three groups: Guoluo group (GL), Huzhu group (HZ) and Shanghai group (SH); Venous blood was collected for routine blood test: red blood cells count(RBC), hemoglobin(HGB), hematocrit(HCT), platelet(PLT); and coagulation index: prothrombin time(PT), interntionl normlized ratio(INR), fibrin(Fib), activated partial thromboplastin time (APTT), thrombin time(TT), continuous non - invasive hemodynamic monitor (CNAP) was used for continuous measurement: cardiac output (CO), heart rate (HR), stroke volume (SV), pulse pressure variation rate (PPV), systemic vascular resistance index (SVRI), mean arterial pressure (MAP); pulse oxygen monitoring instrument is used for monitoring SPO2 (pulse oxygen); the total vascular density (TVD), perfusion vascular density (PVD), proportion of perfused vascular(PPV), and microvascular flow index (MFI) of sublingual microcirculation were observed by using peripheral dark field imaging (SDF) monitoring technique. Results: Compared with the Shanghai group, the RBC and HGB levels in the Huzhu group and the Guoluo group were significantly increased (P＜0.05), while PLT levels were significantly decreased (P＜0.05); The levels of PT, Fib, APTT, TT, CO, HR, SV, MAP and SPO2 in the Huzhu group were significantly decreased (P＜0.05), while the levels of TVD, PVD, PPV and MFI were significantly increased (P＜0.05). In Guoluo group, the levels of HCT, Fib, CO, SV, PPV, MAP, TVD and PVD were significantly increased (P＜0.05), while the levels of PT, INR, TT and SPO2 were significantly decreased (P＜0.05). Compared with the Huzhu group, the levels of RBC, HGB, HCT, Fib and APTT of Guoluo group were significantly increased (P＜0.05); while the levels of SPO2, TVD, PVD, INR and TT were significantly decreased (P＜0.05). Conclusion: The microcirculation of healthy people in different altitude areas is significantly different, and the microcirculation density of healthy people in high altitude areas is significantly higher than that in plain areas, especially in moderate altitude areas. Its special physiological significance is of guiding significance for the treatment of infectious shock and chronic altitude disease in plateau areas.

Microvascular Dysfunction in Peripheral Artery Disease: Is Heat Therapy a Viable Treatment?

Peripheral artery disease (PAD) is characterized by the development of atherosclerotic plaques in the lower-body conduit arteries. PAD is commonly accompanied by microvascular disease, which may result in poor wound healing, plantar ulcer development, and subsequent limb amputation. Understanding the mechanisms underlying the development of plantar ulcers is a critical step in the development of adequate treatment options for patients with PAD. Skin is classified into two major components: glabrous and non-glabrous. These skin types have unique microcirculation characteristics, making it important to differentiate between the two when investigating mechanisms for plantar ulcer development in PAD. There is evidence for a microcirculation compensatory mechanism in PAD. This is evident by the maintenance of basal microcirculation perfusion and capillary filling pressure despite a reduced pressure differential beyond an occlusion in non-critical limb ischemia PAD. The major mechanism for this compensatory system seems to be progressive vasodilation of the arterial network below an occlusion. Recently, heat therapies have emerged as novel treatment options for attenuating the progression of PAD. Heat therapies are capable of stimulating the cardiovascular system, which may lead to beneficial adaptations that may ultimately reduce fatigue during walking in PAD. Early work in this area has shown that full-body heating is capable of generating an acute cardiovascular response, similar to exercise, which has been suggested as the most efficient treatment modality and may generate adaptations with chronic exposure. Heat therapies may emerge as a conservative treatment option capable of attenuating the progression of PAD and ultimately impeding the development of plantar ulcers.

An adaptive fractal model for sublingual microcirculation

The hemodynamic conditions and partial pressure of oxygen in microcirculation generally indicate the status of tissue perfusion, which provides essential information for the assessment and treatment of critical diseases such as sepsis. The human tongue is known to have abundant microcirculation and is an ideal window to observe the microcirculation. At present, the monitoring of sublingual microcirculation is mostly achieved using handheld vital microscopy (HVM). Microcirculation is organized and works as a network. However, HVM can obtain only limited view of few vessels and is not able to acquire information regarding the entire network. In this work, we proposed a method to construct a mathematical network model of sublingual microcirculation to solve the problems. The proposed method is based on fractal analysis to model and simulate the hemodynamic and functional activities of sublingual microcirculation. Specifically, the HVM technology is used to obtain the partial morphological and hemodynamic data of sublingual microcirculation, and fractal analysis is applied thereafter to establish the hemodynamic model of the network based on the data from few vessels. Further, the adaptive regulation mechanism of microcirculation is introduced to enhance the performance of the model. The model was validated by the experimental data and the results are consistent with the characteristics of microcirculation. The work demonstrates the potential of the proposed method in sublingual microcirculation research and for the further assessment of tissue perfusion.

Association between coronary artery disease severity and videocapillaroscopic findings of nail fold capillary circulation

Aim: Endothelial dysfunction plays a significant role in the etiology of coronary artery disease (CAD), which develops due to atherosclerosis, and is a major cause of morbidity and mortality. Nail fold videocapillaroscopy (NVC) assessment is a surrogate marker of endothelial dysfunction. To the best of our knowledge, the relationship between the microcirculation features on NVC and the severity of coronary atherosclerosis has not previously been investigated. In this study, we aimed to investigate the relationship between severity of coronary atherosclerosis (shown by SYNTAX and Gensini scores) and NVC findings which is an indirect indicator of systemic endothelial damage.Methods: The study was designed as a retrospective cohort. One-hundred consecutive patients who underwent coronary angiography (CAG) and had at least one lesion in the epicardial coronary arteries, narrowing the lumen by more than 50%, were included. Coronary angiographic images of the patients were evaluated by two experienced interventional cardiologists and SYNTAX and Gensini scores were calculated. Patients were divided into three groups according to the SYNTAX scores (SYNTAX score ≤22, between 23-32, and ≥33) and two groups according to Gensini scores (Gensini score ≥30 and ˂30). The NVC examinations were performed by a rheumatologist who was experienced in this field, and the reduction in capillary density, presence of dilated capillaries, giant capillary, microhemorrhage, branching, disorganization, tortuosity, avascular area, extravasation, and neoangiogenesis were investigated.Results: Dilated capillary vessels were more common in diabetic patients (85%) than in non-diabetics (66.7%) (P=0.041). Besides, there was no significant difference in NVC parameters between patients with and without diabetes mellitus (P>0.05 for all), with and without hypertension (P>0.05 for all). There was no significant difference between the SYNTAX groups in terms of NVC findings (P>0.05 for all). The NVC findings were similar between Gensini groups (P>0.05 for all). Conclusion: The severity of atherosclerosis surrogated by SYNTAX and Gensini scores was not related to the NVC findings. Therefore, NVC is inappropriate for determining the severity of CAD.

Study of functional state of microcirculatory channel system in periodontal tissues in persons of different age groups

Relevance. The study of age-related features of microcirculation in periodontal tissues, using non-invasive functional research methods, allows us to develop the optimal range of therapeutic measures, as well as form a “personalized therapeutic case”.Purpose. Study of the functional state of the microvasculature in the tissues of the parodont in individuals of various age groups.Materials and methods. A standard dental examination of 80 patients was carried out, the sample of participants was ranked in 4 groups by age: 1 group – 12 years old, 2 group – 15 years old, 3 group – from 16 to 18 years old, 4 group – from 22 to 24 years old. Hygiene and periodontal indices were determined for all patients, such as papillarymarginal-alveolar (PMA) in the Parma modification, the Mulleman bleeding index in the Cowell modification (SBI), and the simplified Green Vermillion index of oral hygiene (OHI–s), caries intensity indicators for a permanent bite (CPI), as well as ultrasound dopplerography of periodontal tissues using the apparatus "Minimax-Doppler-K".Results. When studying microcirculation in periodontal tissues, distinctive characteristics of linear (Vas) and volumetric (Qas) blood flow rates, as well as indicators of pulsation indices (PI) and peripheral resistance (RI) in people of different age groups were recorded.Conclusions. This study confirms the presence of various hemodynamic indicators of periodontal tissues in the studied groups, which is due to structural features of the circulatory system in age periods.

Changes in microcirculation and structural components of the skin under photodynamic effects

Introduction . Distinctive features of microcirculation and their connection with structural disorders in the skin during photodynamic exposure using various photosensitizers (PS) are not well understood. Objective . Comparative analysis of the relationship between morphological abnormalities and changes in blood flow in the skin during photoactivation of PS, taking into consideration the influence on mast cells (MC), structural elements of the dermis and underlying muscle tissue. Materials and methods . In this work were used male Wistar rats (n=46). PS were administered intravenously: Radachlorin (RDC) (5 mg/kg) 3 hours, Coproporphyrin III (CPP) (10 mg/kg) 24 hours before irradiation. To control the accumulation of PS in the skin, methods of fluorescence videodermatoscopy and confocal scanning laser microscopy (CSLM) were used. Laser irradiation (662 and 635 nm) was performed with an energy density of 50 Jcm –2 , the irradiated surface area was 0,78 cm 2 . Laser Doppler flowmetry was used to assess microcirculation in the skin. Results . According to videodermatoscopy, fluorescence maximum values in the R channel were recorded 6-8 hours after administration, and amounted to 4901 [4190; 6732] a. u. for RDC and 2997 [2678; 3351] a. u. for CPP. Using the CSLM method, it was shown that CPP is poorly visualized in the walls of blood vessels. In experiments with RDC, the structures of areolar tissue of the hypodermis are determined. An hour after laser irradiation, in experiments with RDC, as well as with CPP, a significant decrease in blood flow was noted compared with the control to 3,61±0,7 and 4,27±1,4 PU, respectively. Structural changes when using both PS showed endothelial swelling, vasodilation and congestion, hemorrhages in the dermis, and underlying muscle tissue. The amount of MC was reduced. Conclusions . Laser irradiation with the parameters used in the work leads to a significant decrease in blood flow in the skin in experimental animals as a result of photoactivation of PS. CPP requires a higher radiation energy density. Morphological changes were revealed not only at the level of the epidermis, dermis and hypodermis, but also the underlying striated muscle tissue. In the early stages after exposure, massive degranulation of MC is noted with a decrease in their number.

Анализ показателей микроциркуляции симметричных органов человека в условиях изменения артериального давления

It is known that a key link in a pathogenesis of many diseases, including arterial hypertension, is disturbances of microcirculation (MCR). Despite a considerable quantity of the publications on characteristics of MCR at patients with arterial hypertension, questions of functional asymmetry these characteristics and their interrelation with blood pressure till now are a little studied. Therefore the purpose of the present research was studying of features of left-right asymmetry in regulation of a vascular tonus of symmetric areas of paired organs under changes in blood pressure. Measurements of characteristics of microcirculation spent at 5 healthy volunteers from 50 till 70 years by means of a LDF method (device LAKK-02 NPP LASMA - two channels). The sensors LDF signal recorded on the symmetric parties of the bottom parts of the right and left shoulder in the points located on 3 cm above an elbow bend. Characteristics of MCR (perfusion) and amplitudes of frequency spectrum: neurogenic, myogenetic, respiratory and cardiac, and correlations between them was estimated. Correlation relationships between various components of a vascular tonus showed left-right asymmetry that has been not associated with blood pressure value. Low values of the correlation coefficients between the MCR and AD obtained in this study indicate the absence of linear regression dependencies between these values, but do not exclude the presence of nonlinear relationships between them.

Features of microcirculation and effectiveness of conservative therapy in exacerbation of chronic tonsillitis

Objectives - to study the characteristics of microcirculation in patients with chronic tonsillitis, caused by Streptococcus pyogenes with confirmed sensitivity to the group of inhibitor-protected penicillins. Material and methods. The study of micro vascular blood flow in the tonsils was performed with laser Doppler flowmetry, using the multifunctional diagnostic complex "LAKK-M" (Russia, 2010). Results. The analysis of the microcirculation parameters of patients in group I showed significant changes in the functioning of their micro vascular blood flow, if compared to patients in the control group. The intensity of blood flow in the tonsils was significantly less in the individuals with low sensitivity to antibacterial therapy. Conclusion. 1. In case of the clinical inefficacy of the antibacterial therapy in patients with microflora, sensitive in vitro to the same antibiotics, it is necessary to study the microcirculation in their tonsils. 2. Perfusion indicators can be used as an additional express-criterion for predicting the effectiveness of the conservative therapy. 3. If there is a significant change in the micro vascular blood flow, it is necessary to consider the possibility of surgical treatment of patients with chronic tonsillitis.

Particularities of microcirculation of athletes training for endurance, and its factors

The aim is to reveal the features of microcirculation of athletes with various sport qualifications practicing cyclic endurance sports, as well as its dependence on the VEGF (vascular endothelial growth factor) level and hematological parameters. Research materials and methods. The study involved athletes aged 18-22 practicing track-and-field (middle and long distances, from 1st rank to Master of Sports of the Russian Federation), swimming (middle distances, from 1st rank to Master of Sports of the Russian Federation), skiing (from 1st rank to Master of Sports of the Russian Federation), and non-athletes. We utilized a laser detection to record parameters of peripheral blood flow and tissue fluorescence amplitudes. Research results and discussion. We recorded significant difference in microcirculation parameters for skiers and field athletes. Skiers demonstrated a lower value of average perfusion, while field athletes showed its double predominance in contrast with skiers. At the same time, cooling of the studied area caused no difference between the studied groups. Heating of the studied area resulted in the statistically significant changes in microcirculation between groups of skiers in contrast with field athletes and swimmers, as well as swimmers, in contrast with field athletes and non-athletes. At the same time, the VEGF level had correlations with the microcirculation of field athletes, and it was recorded with the NADN parameter under the cooling (r = 0.89; p = 0.019) and heating (r = 0, 94; p = 0.005) conditions. Conclusion. We revealed the signs of long-term adaptation of peripheral blood flow of athletes conditioned by the type and conditions of sport activities. It results in difference in perfusion of the studied skin area.

Peculiarities of microcirculation in periodont tissues in children of key age groups sufficient type 1 diabetes. Part II

Relevance. Morpho-functional changes in peripheral circulation established in type 1 diabetes mellitus correlate with changes in central hemodynamics, allowing the use of microcirculation indicators as diagnostic and prognostic criteria for assessing the degree of functional vascular disorders. Identifcation of microcirculation features of the blood by the method of laser Doppler flowmetry in children with different experience of type 1 diabetes in key age categories.Materials and methods. The study included 67 children with type 1 diabetes mellitus aged 12-15 years with an experience of the disease from six months to ten years. The comparison group consisted of 38 healthy children. The state of the microvasculature was assessed by laser Doppler flowmetry using a laser analyzer for capillary blood flow LAKK-OP.Results. In children with an experience of type 1 diabetes of less than two years, microcirculation disorders in periodontal tissues correspond to the hyperemic form, accompanied by increased perfusion, a decrease in the amplitude of low-frequency oscillations, increased heart rate, high blood flling, and blood flow bypass. For children with an endocrinopathy experience of more than three years, microcirculation disorders correspond to a stagnant form, combined with a decrease in perfusion due to stagnation of blood in the venular link, endothelial domination with suppression of neurogenic and cardiac fluctuations, low efciency and redistribution of blood flow in favor of the nutritive link.Conclusions. With the increase in experience, the degree of compensation of type 1 diabetes, the progression of diabetic microangiopathy, it is advisable to designate two stages of development of microcirculatory disorders. Early – compensatory with active adaptation, including neurogenic and endothelial regulation mechanisms. Late – decompensation with passive adaptation, supporting the effectiveness of microcirculation due to myogenic control of regulation, shunting and increasing the rate of blood outflow.

Nonlinear analysis of fluctuations of microcirculation parameters in symmetrical organs of humans by laser doppler flowmetry

Purpose– the study the nonlinear dynamics of microcirculation parameters in human symmetrical organs.Material and Methods. Parameters of microcirculation were measured in healthy volunteers (aged between 50 and 70 years) by means of laser Doppler flowmetry (LDF). LDF signal transducers were fixed symmetrically on the lower parts of the right and left shoulders (3 cm above the elbow bend). The degree of chaoticity of microcirculation parameters as a nonlinear dynamic process was estimated using Hausdorff’s index, relative entropy and characteristics of phase portraits. Along with components of the amplitude-and-frequency range for blood flow fluctuations (myogenic, neurogenic, respiratory, and cardiac) was estimated and correlations between all characteristics of microcirculation in both sides of the body were done.Results.Asymmetry of correlation relationships of nonlinear dynamics parameters and components of the amplitude-andfrequency range for blood flow fluctuations of right and left sides of the body was revealed. Hausdorff index in the left side correlated not only with the average value of perfusion and with the coefficient of variation in the same side (r1 = –0,68; r2 =–0,51), but also with correlation dimension of chaos in the opposite side (r=0,49). Similarly, entropy in the left side correlated not only with the average value of perfusion and coefficient of variation in the left (r1 =0,43; r2 =0,60), but also with the entropy and correlation dimension of chaos in the right side (r1 =0,48; r2 =–0,41). The neurogenic component in the left side positively correlated with the myogenic component in the same side (r=0,71). A positive correlation was observed between the neurogenic component in right side and myogenic component in the opposite side (r=0,57). Asymmetry of correlation relationships was also revealed for the respiratory and cardiac components.Conclusions. Our results illustrate the specific regulation of blood flow in micro vessels of paired organs, which is associated with functional asymmetry. The physiological mechanisms for this asymmetry require further experimental and clinical studies.

Peculiarities of microcirculation in peridont tissues in children of key age groups sufficient type 1 diabetes. Part I

The relevance of the research topic.Morpho-functional changes in peripheral circulation established in type 1 diabetes mellitus correlate with changes in central hemodynamics, allowing the use of microcirculation indicators as diagnostic and prognostic criteria for assessing the degree of functional vascular disorders.Purpose– identifcation of microcirculation features of the blood by the method of laser Doppler flowmetry in children with different experience of type 1 diabetes in key age categories.Methods.The study included 67 children with type 1 diabetes mellitus aged 12-15 years with an experience of the disease from six months to ten years. The comparison group consisted of 38 healthy children. The state of the microvasculature was assessed by laser Doppler flowmetry using a laser analyzer for capillary blood flow LAKK-OP.Results.In children with an experience of type 1 diabetes of less than two years, microcirculation disorders in periodontal tissues correspond to the hyperemic form, accompanied by increased perfusion, a decrease in the amplitude of low-frequency oscillations, increased heart rate, high blood flling, and blood flow bypass. For children with an endocrinopathy experience of more than three years, microcirculation disorders correspond to a stagnant form, combined with a decrease in perfusion due to stagnation of blood in the venular link, endothelial domination with suppression of neurogenic and cardiac fluctuations, low effciency and redistribution of blood flow in favor of the nutritive link.Summary.With the increase in experience, the degree of compensation of type 1 diabetes, the progression of diabetic microangiopathy, it is advisable to designate two stages of development of microcirculatory disorders. Early - compensatory with active adaptation, including neurogenic and endothelial regulation mechanisms. Late - decompensation with passive adaptation, supporting the effectiveness of microcirculation due to myogenic control of regulation, shunting and increasing the rate of blood outflow.

Cardioprotection by spermidine does not depend on structural characteristics of the myocardial microcirculation in aged mice.

Ageing is associated with cardiovascular disease and reduced cardiac function. This cardiac functional decline is accompanied by cardiac remodeling and alterations in cardiomyocyte composition. Recently, it was shown that the natural polyamine spermidine preserves cardiac function and cardiomyocyte composition in old mice. As cardiac function critically relies on blood supply, we tested whether spermidine has also beneficial effects on ageing-associated changes of the myocardial microcirculation. Using transmission electron microscopy, the left ventricular capillaries of young (4-months old) and aged (24-months old) C57BL/6J male mice were investigated by stereology. Aged mice were subdivided into an untreated group and a group that was fed spermidine late in life for 6 months. Specifically, total volume, surface area and length of capillaries as well as endothelial thickness were estimated. Additionally, the total length of precapillary arterioles was assessed. The protein level of VEGF-A was measured using Western blot. Ageing was associated with whole heart and left ventricular hypertrophy. All total capillary-related values (including volume, surface area and length) were significantly higher in 24-month-old mice compared with 4-month-old mice. Moreover, VEGF-A expression was significantly enhanced in aged mice. The mean thickness of the endothelium was not different, but the mean area of myocardium supplied by capillaries was smaller in old mice. Spermidine treatment had no significant effect on the ageing-associated structural changes or VEGF-A expression. In conclusion, in the left ventricles of aged mice the growth of capillaries and arterioles supplying cardiomyocytes were in proportion to whole organ hypertrophy. Spermidine had no effect on quantitative characteristics of capillaries or arterioles, suggesting that the beneficial effects of spermidine on the ageing heart do not depend on the quantitative structural characteristics of the microcirculation which does not exclude potential functional differences between the groups.

Ultrasound doppler in evaluation of microcirculation features in the pulp of permanent teeth with formed roots

Ultrasound doppler in evaluation of microcirculation features in the pulp of permanent teeth with formed roots

Diagnosis of microcirculation features in intestinal anastomosis to prevent its failure

Laser doppler flowmetry is a way to identify predictors of diseases and complications associated with blood supply disorders. Registration of absolute values for results of this method allows to eliminate the subjective factor. Previous studies demonstrate the possibility of using this technique in clinical practice. The effectiveness for assessing the quality of blood supply of the tissues requires further studying.

The features of microcirculation in the nasal mucosa in children with adenoid hypertrophy and otitis media with effusion

The features of microcirculation in the nasal mucosa in children with adenoid hypertrophy and otitis media with effusion

The microcirculatory changes in patients with intermittent claudication after endovascular restoration of main blood flow to the extremity

The functional state of microvascular blood flow is the major pathogenic determinant in patients with intermittent claudication (IC). Revealing features of microcirculation (MC) shifts has been especially valuable after endovascular interventions. Purpose. To assess the alterations in MC profile after the restoration of main blood flow to affected extremity in patients with IC. Material and methods. MC was assessed by laser Doppler flowmehy in 37 patients before and 1 month after lower extremity angioplasty. Results. Restoration of main blood flow was associated with increased nutritional blood flow by 56.0 %, decreased arteriole-venule shunts by 30.7 % and venous congestion by 13.5 %. Conclusion. Endovascular interventions in patients with IC are associated with recovery of balance in MC processes.