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PubMedDate not supplied

[Effect of perftoran on microcirculation and target organs in early atherogenesis].

Effects of perfluoran, a plasma substitute with a gas-transport function, were studied at the stage of dyslipidogenic microangiopathy in rabbits. Changes in microcirculation, hemorheology, morphology of the liver, phospholipid composition of hepatocytic membranes were examined histologically, histochemically, electron microscopically and biochemically. Perfluoran produced a positive effect on microcirculation, phospholipid composition of hepatocytic membranes. Individual features of these parameters' dynamics were determined for animals.

Animals↗
PubMedDate not supplied

[Indicators of central hemodynamics and microcirculation in patients with stenocardia for evaluation of the effectiveness of the treatment by plasmosorption].

The myocardial contractile function and microcirculation were studied in 39 patients with angina of effort, III-IV FC before and after plasmosorption course treatment in the presence of drug therapy. A positive clinical effect was recorded in 86% of cases that resulted in disappearance of anginal attacks, reduction of antianginal drug therapy in the presence of improved central hemodynamics and increased myocardial contractility and microcirculation.

Adult↗
PubMedDate not supplied

[Use of Doppler fluorometry for the assessment of microcirculation in patients with severe mechanical trauma].

Described in the paper are issues related with studying the micro-hemocirculation in victims with mechanical shock-genesis trauma by using the laser Doppler fluorimetry. The results are indicative of a nature of changes occurred in the microcirculation system in such victims with different-severity traumatic shock. It is concluded that, in principle, it is possible to use the method in question within the diagnostics of the impaired microcirculation in patients with shock-genesis lesions at disease exacerbation.

Adult↗
PubMed2004

Laser Doppler flowmetry assessment of microcirculation in upper extremities before and in long-term period after harvesting of radial artery.

Radial artery (RA) is rather commonly used as a graft for autoarterial myocardial revascularization. Consequences of RA harvesting for the development of ischemic disturbances in distal hand segments are poorly understood. The paper presents assessment of hand microcirculation (HMC) before and in late postoperative period after RA harvesting with modern precise diagnostic method - laser Doppler flowmetry (LDF). LDF assessment of HMC was carried out in 80 patients with ischemic heart disease (160 hands) to evaluate the possibility of RA harvesting for coronary artery bypass surgery. HMC classification was developed on the base of these measurements: type 1 -normocirculatory HMC: 6.7-17 ml/min/100 g (58%); type 2 - vasospastic HMC: < or = 6.7 ml/min/100 g (20%); type 3 - hyperemic HMC: > or = 17 ml/min/100 g (22%). In 34% of cases preoperative examination revealed microcirculatory asymmetry between right and left hands. Based on preoperative examination results in 22.9% of cases the decision was made to refuse from RA excision because of positive collateral circulation test developed in our Institute (positive decision about Patent award according to appeal No2000122582/14 (023905) from 28.08.2000). In 14 patients (14 upper extremities) HMC was measured before and 1-1.5 years after RA harvesting. After RA excision baseline HMC in operated hand reduced significantly while maximal HMC reserve remained at the level close to preoperative one. Postoperative HNMC alterations evidence of adequate preoperative assessment of hand collateral circulation potential. In case of blood flow asymmetry RA must be taken from the hand with higher blood supply and adequate collateral microcirculation.

Arteriovenous Shunt, Surgical↗
PubMed2004

Plasma lipid levels, blood rheology, platelet aggregation, microcirculation state and oxygen transfer to tissues in young and middle-aged healthy people.

It has been reported that dyslipidemia is associated with rheological and microcirculatory abnormalities in patients with ischaemic heart disease. However, it is not known how this system changes in men and women with ageing. In healthy young and middle-aged subjects the following parameters were evaluated: total plasma cholesterol, triglycerides and HDL-cholesterol levels, deformability of erythrocytes, red blood cell and platelet aggregations, blood and plasma viscosity, neutrophils' cytosolic [Ca2+]i and microviscosity of the bilayer's total lipid phase and the annular near-protein zone of the membranes. Using intravital computer-associated microscopic system we investigated the microcirculation of bulbar conjunctiva. Oxygen transfer characteristics were measured with a Radiometer TCM2 monitor. It is evident from the data obtained that in men of middle age the total plasma cholesterol and triglyceride levels are higher in comparison with other groups. The rheological behavior of red blood cell and platelet aggregations in men differ from that in women. Neutrophils activation in healthy subjects was not recorded. Our results show that changes of the blood rheological properties of men 35-50 years old can lead to disturbances of the microcirculation.

Adult↗
PubMed2004

Sildenafil improves cutaneous microcirculation in patients with coronary artery disease: a monocentric, prospective, double-blind, placebo-controlled, randomized cross-over study.

UNLABELLED: Endothelial dysfunction of precapillary arterioles impairs nutritional microcirculation at rest as well as during post-ischemic reactive hyperemia. In this monocentric, prospective, double-blind, placebo-controlled, randomized cross-over study we investigated the acute effect of 50 mg sildenafil, a selective PDE-5 inhibitor, on resting and post-ischemic capillary circulation in twenty patients with angiographically confirmed coronary artery disease not taking nitrates or NO-donors. Mean erythrocyte velocity in digital nail-fold capillaries was determined before and after sildenafil and placebo, both baseline and after a three-minutes supra-systolic occlusion of the upper arm. Primary efficacy parameter was the drug effect on peak velocity during reactive hyperemia (peak velocity: V(max)). Post ischemic maximal capillary erythrocyte velocity V(max) significantly increased by 47% one hour after 50 mg sildenafil (mean value+/-standard deviation: 0.85+/-0.42 mm/s vs. 0.58+/-0.18 mm/s at baseline, p=0.0023), whereas placebo had no effect (p=0.5248). The difference between sildenafil and placebo was significant (p=0.0129) and sildenafil's effect can be regarded as biometrically highly relevant with standardized difference according to Cohen of 0.81. In spite a small decrease of both systolic and diastolic blood pressure after sildenafil, sildenafil significantly increased capillary erythrocyte velocity at rest. CONCLUSION: A single oral dose of sildenafil significantly increased resting and post-ischemic cutaneous capillary circulation in patients with coronary artery disease. Future studies should assess whether sildenafil also improves nutritional capillary blood flow in other organs and in other diseases with impaired endothelial function and microcirculation, for example in diabetic microangiopathy.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed2003

The use of light reflection rheography in diagnosing venous disease and arterial microcirculation.

The use of light reflection rheography (LRR) has reached an important level in the past few years. Using the originally construed and conceived RRL 001 device, we present the basic principles, the working technique and the limits of this method. We will use two magnetic amplifiers, one for the finger tip, which measures the capillary blood flow at this level and a venous magnetic amplifier which measures the blood flow in the venous plexuses at a 1-2 mm depth. The detection of the blood flow in the subcutaneous (hypodermic) venous areas leads to the diagnosis of profound thrombophlebitis and venous valves insufficiency. The detection of the capillary flow in the finger tip, its presentation as a curve, measuring the pressure of the inter digital arteries (using Riva Rocci method), establishing the index of systolic pressure make possible the understanding of the gravity of the existing hemodynamic disorders (especially in what concerns the Raynaud syndromes), the supervision of the original disease and the efficiency of the treatment. Weindorf was the first one to use the RRL technique in medicine in 1985 and, after 1997, it has been developed through Sproule's work. Within The Medical Clinic of the Municipal Hospital, a light reflection rheograph has been built and forwarded as innovation. The device has been used for 2 years in the diagnosis of venous disorders and peripheral microcirculation disorders. In this article we present the principles of the LRR examination of the lower limb venous system and of the microcirculation of the fingers of the upper limbs, an examination based upon our own experience which includes 72 examinations.

Fingers↗
PubMed2004

[The effects of extracts from Herba Lagopsis on lymph microcirculation of acute blood stasis rats].

OBJECTIVE: To observe the effects of the extracts from Herba Lagopsis (HLE) on lymph microcirculation of acute blood stasis rats. METHODS: The acute blood stasis model was made by iv dextran (10 ml/kg) within 1 min. After 6 minutes, HLE(1.0g/kg) was given intravenously to the treatment group and the same volume of NS was done in the normal control group. The changes of contractility of mesenteric micro-lymphatics (ML) was observed by using a vital microscope with TV recorder. RESULTS: HLE could markedly improve the ML spontaneous constraction frequency, lymphatics constractive activity (Index I), total lymphatics constractive activity (Index II) and lymphatics dynamics (L. D-Index) (P < 0.05 approximately 0.01). CONCLUSION: HLE played an important role in lymph microcirculation of acute blood stasis rats.

Acute Disease↗
PubMed1992

[Critique of Starling's hypothesis of the microcirculation].

By means of average estimation of the parameters on the capillary wall in experiments the capillary is supposed to content one pore only. This situation is not relevant to the practice of blood supply and leads to misinterpretation of the Starling's equation which can not represent the theoretical conception of the microcirculation in tissues. In order to avoid mistakes the usage of system theoretical analytic methods is indicated. This is the alternative way which is able to cover all kinds of preconditions of microcirculation in different tissues.

Blood Pressure↗
PubMed1992

Pathophysiology of the gastric microcirculation.

Mucosal blood flow performs an extremely important role in microcirculation wherein alterations necessarily lead to severe gastric and duodenal mucosal lesions. The removal of back-diffused H+ ions through the adaptation of microcirculatory flow represents a valid defence mechanism. The blood flow's inability to contain H+ back-diffusion lies at the bottom of rapid-onset acute mucosal lesions; moreover, it probably contributes to the onset of chronic ulcer in certain areas already precariously supplied, because of the breakdown of the mucosal barrier or a further reduction in blood supply. Portal hypertension leads to altered blood flow in the gastric microcirculation. This haemo-dynamic condition brings about a series of endoscopically evident changes which are probably a consequence of the conspicuous increase in mucosal and submucosal vascular area. This haemodynamic situation may be an aetiopatho-genetic factor in the cirrhotic subject's marked sensitivity to gastric mucosal damage.

Animals↗
PubMed2005

[Preliminary study on the improvement of wound microcirculation and retrospection on several methods of the management of deep partial thickness burn wound].

OBJECTIVE: To analyze several methods of wound repair for deep partial thickness burn wounds retrospectively, so as to evaluate the significance of improvement of wound microcirculation on wound healing. METHODS: (1) 2,976 burn patients admitted to our department were enrolled in the study, among them 614 undertook tangential excision, 32, eschar abrasion, 86 allo-skin coverage after debridement, 1836 tropical application of silver sulfadiazine and 408 with traditional Chinese medicine (Jing Wan Hong ointment) with gauze bandage. The results of the management with different methods were compared. (2) Rat model with deep partial thickness burn was reproduced and topical application of silver sulfadiazine was given. The rats were randomly divided into control (n = 10, with normal saline injected via caudal vein within 5 minutes postburn), and treatment (n = 10, with batroxobin injected via caudal vein within 5 minutes postburn) groups. The blood flow perfusion unit in the wound skin was measured before burn and at 0.5 to 72 postburn hours by Laser Doppler. The wound healing rate, contraction rate and wound healing time in each group were calculated on 14 and 18 postburn days (PBDs). The number of hair follicles after wound healing was observed by histological method. RESULTS: (1) The burn wound treated by tangential excision healed within 2 to 3 post operation weeks (POWs), with the healing rate of 94.8% in patients with burn covering 50% - 70% TBSA and 93.4% in those with burn of 80% approximately 98% TBSA. The healing time of patients with allo-grafts coverage after eschar abrasion was 13.8 +/- 2.1 days without scar formation. The wound healing time was 18.0 +/- 2.3 day in 82 patients with allo-graft coverage after debridement, and it was 26.0 +/- 3.2 days with subeschar healing in 1658 patients with topical application of silver sulfadiazine. Infection in burn wound was encountered in most patients undergoing traditional Chinese medicine bandage treatment with wound healing time of 26.0 +/- 2.8 days in the lower extremities. (2) The blood flow perfusion unit of the rats in the treatment group was significantly higher than that in the control group (P < 0.01). The wound healing rate in treatment group on 14 and 18 PBD was obviously higher than that in the control group (P < 0.01). But the wound contraction rate in the two groups was similar (P > 0.05). The wound healing time in treatment group was much shorter than that in control group (P < 0.01). A few hair follicles remained in the dermis of the rats in the control group on 30 PBD, and the number was evidently smaller than that in the treatment group (P < 0.01). CONCLUSION: Early tangential excision and eschar abrasion remained better methods in the management of deep partial thickness burn wounds, as they could ameliorate burn wound infection, shorten treatment period, raise wound healing rate and quality. Application of batroxobin could accelerate wound healing rate by improving wound microcirculation in deep partial thickness burn wound.

Adult↗
PubMed2005

[Laser correction of microcirculation disorders in patients having CHD with hypercholesterinemia].

The study demonstrates that hypercholesterinemia in patients with coronary heart disease (CHD) is associated with functional depression of microcirculation, increase in total peripheral vascular resistance, reduction in the functional efficiency of heart and decrease in activity tolerance. After receiving a course of low-intensity infrared laser radiation treatment the patients displayed positive changes in blood lipid spectrum, which was associated with improvement in microcirculation, decrease in afterload, increase in economization of heart functioning and activity tolerance. The obtained results demonstrate that the hypolipidemic effect of laser radiation is a substantial factor in the regression of CHD manifestations.

Adult↗
PubMedDate not supplied

Influence of complementary Viscum album (Iscador) administration on microcirculation and immune system of ear, nose and throat carcinoma patients treated with radiation and chemotherapy.

With the techniques of vital microscopic and reflection spectrometric imaging, representative characteristics of microcirculation and immunology of white blood cells were evaluated before, during and after radiotherapy and chemotherapy of patients suffering from ear, nose and throat carcinomas. Adverse effects of radiotherapy and chemotherapy on the microcirculation and the immune system were decreased and reconstitution processes were accelerated by complementary administration of a standardized mistletoe extract (Iscador).

Aged↗
PubMed1992

[The microvasculature and microcirculation of the peri-macular capillary network. New diagnostic possibilities with the scanning laser ophthalmoscope].

The scanning laser technique makes it possible for the first time to perform objective measurements of blood flow velocities in retinal capillaries. This new technique allows for continuous recording of retinal pictures at high resolution. Only the quality of the optical media of the eye limits the resolution of the retinal image. Sequences with a sample frequency of up to 50 images/s can be stored using a digital recorder. In these digital sequences the moving blood stream in retinal capillaries is visible. Segments of high and low fluorescence can be observed moving through the capillary network of the perifoveal capillaries. The flow velocities of these segments can be measured objectively using image analysis. In addition, morphologic information about the perifoveal capillary bed can be obtained by this new technique. Determination of flow velocities and morphological parameters give an objective means of assessing oxygen supply to the macular tissue. Furthermore, the degree of changes in the perifoveal microcirculation may provide objective data for estimating the prognosis of diabetic or senile maculopathy. Further investigation is needed to examine the relationship between changes in perifoveal microcirculation and the development of macular edema in various diseases.

Adult↗
PubMed2005

[Assessment of microcirculation disturbance in patients with coronary ectasia by ATP-loading 99mTc-tetrofosmin myocardial SPECT].

UNLABELLED: Patients with coronary ectasia often develop chest pain and reveal ischemic changes on electrocardiograms and reduced left ventricular wall motion on left ventriculography, in the absence of epicardial coronary artery stenotic regions. We examined the disturbances in the coronary microcirculation in patients with coronary ectasia using left ventriculography and ATP loading 99mTc-tetrofosmin myocardial single photon emission computed tomography (SPECT) before and after administration of a coronary vasodilator and antiplatelet agents. METHODS: Twenty patients in whom coronary angiography revealed diffuse coronary artery ectasia but no stenotic regions were enrolled in this study. Left ventriculography and ATP loading 99mTc-tetrofosmin myocardial SPECT were performed before and after administration of the coronary vasodilator, nicorandil, as well as that of the antiplatelet agents, aspirin and ticlopidine. RESULTS: (1) The ejection fraction in left ventriculography was 48.3 +/- 17.4% before, and 56.6 +/- 18.3% after the drug administration, the ejection fraction was improved after the drug administration (p < 0.05). (2) Before the drug administration, the total defect scores on 99mTc-tetrofosmin myocardial SPECT were 5.9 +/- 3.1 and 8.8 +/- 2.7 in the ATP-loading and rest images, respectively (p < 0.05), and the corresponding scores after the drug administration were 4.1 +/- 3.0 and 5.4 +/- 3.1, respectively (N.S.). Thus, the total defect scores in the ATP-loading and rest images improved after the drug administration (p < 0.05). CONCLUSION: Myocardial damage in patients with coronary ectasia might be induced by microthrombotic embolism and microcirculation disturbance.

Adenosine Triphosphate↗
PubMed2005

Blockade of spinal nitric oxide synthase on blood pressure variability and hepatic microcirculation.

BACKGROUND: We previously demonstrated that intrathecal administration of N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, increased systemic arterial blood pressure in a dose-dependent manner in rats. The aim of the study was to investigate the participation of autonomic nervous system on L-NAME-induced hypertension and also illuminate its effects on hepatic microcirculation in rats. METHODS: Eight Spraque-Dawley rats were used and initially anesthetized with ketamine 120 mg/kg, intraperitoneally supplemented by intravenous infusion of ketamine at 30 mg/kg/h for maintenance. Surgical preparations included cannulations of right femoral artery and vein to obtain systemic arterial pressure signals and administer anesthetic drug. A mini-laparotomy was made to facilitate the insertion of a microdialysis probe and attachment of a laser Doppler probe to the middle lobe of the liver. On experiment, L-NAME was administered via the previously placed intrathecal catheter at 0, 0.37, 0.74, and 1.48 micromol in sequence at a 2-h interval. RESULTS: The results showed that the arterial blood pressure increased in a dose-dependent manner. By the same token, the power density of very low frequency (VLF) also increased. The low frequency (LF): high frequency (HF) ratio shifted toward parasympathetic dominance. Blood flow to the liver was unchanged except slightly decreased in the animals receiving 0.37 micromol. The levels of monoethylglycinexylidide (MEGX), an index of hepatic metabolism, were unchanged throughout the experiment. CONCLUSIONS: We concluded that the blockade of spinal nitric oxide synthase by intrathecal administration of L-NAME significantly increased vasomotor tone in a dose-dependent manner and as a consequence induced a reflex sympathetic inhibition. Hepatic microcirculation was stable with the applied doses.

Animals↗
PubMed2005

[A study on myocardial microcirculation with coronary angiographic impulse response function].

We have established a digital coronary angiograph-analyzing system on the principle of coronary angiographic impulse response, and combined the system with the quantitative coronary analysis (QCA) for investigating the coronary microcirculation (Tmicro(-1)), the minimal stenotic diameter of coronary (MLD) and coronary hemodynamic parameters (mAP, CFV, Rcor) in 20 patients with coronary stenosis. The results showed the minimal stenotic diameter (MLD) and Tmicro(-1) decreased, with the increase of stenosis of proximal coronary. After successful percutaneous coronary intervention treatment, the Tmicro(-1) increased with the increase of MLD and was in linear correlation with MLD (r = 0.87, P < 0.001). In conclusion, The index Tmicro(-1) detected by coronary digital angiographic impulse response analysis system in combination with CFV and QCA would help to evaluate the level of integrated diagnosis of coronary lesion in regard to anatomy and physiology as well as to macro and microcirculation.

Coronary Angiography↗