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Background: Management of avulsion injuries remains a challenge due to necrosis. The aim of the present study is to create an experimental model reproducing an avulsion injury and investigate the effects of hyperoxygenated solution (HOS), a method of oxygen delivery that has been widely used in the therapy of ischaemia-hypoxia diseases, on avulsion injury flap survival in rats., Methods: Forty male rats were divided into four groups (n = 10 each). Dorsal random pattern flaps measuring 3 × 9 cm, including the panniculus carnosus, were elevated and run over by the skin avulsion model machine, and the flaps were then sutured into their original places. The sham+HOS and avulsion+HOS groups received intravenous HOS (20 ml/kg) each day for 7 days after the operation. The sham+saline and avulsion+saline groups received intravenous saline solution (20 ml/kg) each day for 7 days after the operation. Percutaneous O 2 pressure (TcpO 2 ) measurement , serial examinations of skin flap blood perfusion, skin flap survival evaluation and histopathology were performed to assess the efficacy of HOS on avulsion injury., Results: Compared to the avulsion+saline groups, TcpO 2 was significantly higher in the avulsion+HOS groups at 15, 30 and 60 min after infusion (P < 0.05). The blood perfusion of flaps in the avulsion+HOS group was higher than in the avulsion+saline group (P < 0.05). The survival rate was higher in the avulsion+HOS group than in the avulsion+saline group (P < 0.05), and the histopathology assays supported the data., Conclusion: We succeeded in developing an avulsion injury model and demonstrated that HOS could improve the survival of the avulsion injury flaps in rats by effectively increasing the local oxygen content and blood perfusion and ameliorating inflammatory damage., Competing Interests: Declaration of Competing Interest The authors have no financial interests to declare in relation to the content of this article., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Timely diagnostics of microcirculatory system abnormalities, which are the most severe diabetic complications, is one of the major problems facing modern health care. Functional abnormalities manifest themselves earlier than the structural ones, and therefore their assessment is the issue of primary importance. In this study Laser Doppler flowmetry, a noninvasive technique for the cutaneous blood flow monitoring, was utilized together with local temperature tests and wavelet analysis. The study of the blood flow in the microvascular bed of toes was carried out in the control group of 40 healthy subjects and in two groups of 17 type 1 and 23 type 2 diabetic patients. The local temperature tests demonstrated that the diabetic patients have impaired vasodilation in response to local heating. The tendency for impaired low frequency pulsations of the blood flow associated with endothelial and neurogenic activities in both diabetes groups was observed. Local thermal tests induced variations in perfusion and its spectral characteristics, which were different in the groups under study. In our opinion, the obtained preliminary results can be a basis for further research and provide a deeper understanding of pathological processes that drive microvascular abnormalities caused by diabetes mellitus., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Aim: To reveal the features of microcirculatory parameters in compensated and decompensated type 2 diabetes mellitus (T2DM)., Subjects and Methods: A total of 196 patients with T2DM were examined and divided into 2 groups: 1) 52 patients (40.4% of men) aged 52.8±8.7 years with compensated T2DM (glycated hemoglobin (HbA1с), 6.3±0.5%); 2) 68 patients (38.2% of men) aged 52.8±8.1 years with decompensated T2DM (HbA1с, 9.4±1.7%). Both patient groups had concomitant hypertension (its prevalence, degree, stage of hypertension were comparable). A control group consisted of 76 volunteers (40.8% of men) aged 52.2±8.7 years with normal carbohydrate metabolism and without signs of cardiovascular disease (HbA1с, 5.3±0.49%). Capillary blood flow in the finger nail-fold area was investigated in all the participants. A digital optical capillaroscope with image-processing software was used to obtain quantitative blood microcirculatory parameters. The diameters of arterial and venous capillary segments were measured, by calculating the remodeling rate. The degree of capillary tortuosity, network density, and polymorphism and the size of the perivascular zone (PZ) were estimated. Blood rheological properties and capillary blood flow velocity were also investigated., Results: The decompensated T2DM group compared to the compensated T2DM group was found to have a narrowing of the arterial capillary segment diameter (8.4±2.0 µm; p=0.009) and an increase in remodeling rates (1.47±0.22; p=0.000). The tendency of the PZ size to be larger in patients with decompensated T2DM compared to those with compensated T2DM (p=0.080) and the increase in this indicator compared to the control group (p=0.001) reflect the presence of edema syndrome in Group 2, as laboratory confirmed by a statistically significantly elevated sodium level (p=0.000; p=0.006). The enlarged venous capillary segment demonstrates involvement of the venous component in microcirculatory disorders in T2DM. The reduction in the density of the capillary network and the increase in capillary tortuosity and polymorphism, which were also observed in the patients of both groups versus the control group, are referred to as disorders that are characteristic of T2DM., Conclusion: In decompensated T2DM, capillary bed structural and functional changes are found as a narrowing of the arterial capillary segment, an increase in the rate of remodeling, and enlargement of the PZ. Digital capillaroscopy opens up new possibilities for assessing the magnitude of changes in the microcirculatory system in DM and can simultaneously evaluate the efficiency of treatment, by monitoring the status of the microvasculature.

Purpose: To test the hematologic effects of low intensity 650 nm laser irradiation on hypercholesterolemia rabbits., Methods: Ten male big-eared rabbits were selected from hypercholesterolemia animal model-making and divided into model group and laser treatment groups. Five normal rabbits were selected as control group. Auricle root irradiation of 650 nm laser 100 mW in 30 min were applied on treatment group twice a day, treatment of 6 days in one week, 20 weeks course of treatment. Changes in blood lipid, microcirculation, rheological properties, and aggregation morphology of erythrocytes were observed every two weeks. Histopathological examination were performed in the end of experiments., Results: After 20 weeks' treatment, triglyceride (TG), cholesterol (CHO), high density lipoprotein (HDL) and low density lipoprotein (LDL) of serum in hypercholesterolemia groups showed less changes in the first 4 weeks, butdifferent decreasing trends were shownin the next 16 weeks' therapy. Erythrocytes aggregation of model groups showed rouleau state, while red blood cells in control group showed fine homodisperse, erythrocytes in treatment group performed better dispersion than model groups. Erythrocyte deformation index (DI) and blood flow value showed a statistic improvement in treatment group than control and model group (P<0.01). Value of DI in treatment group decreased after 18 weeks than values before therapy (P<0.01). Varying degrees of Aorta plaque formation was observed for individual difference in model and treatment groups, while no plaque was found in control group., Conclusions: Low energy laser improve microcirculation, rheological properties and blood lipid that might be related with erythrocytes aggregation and deformability.