Assessment of Microcirculation and Microrheological Parameters of Blood in Patients With Type 2 Diabetes Mellitus Using Biophotonics Techniques.

In this study, the parameters of blood microcirculation and microrheology were measured using the methods of laser aggregometry and optical tweezers in vitro, as well as the method of digital capillaroscopy in vivo. It was shown that in patients suffering from type 2 diabetes mellitus, an increase in the number of RBC aggregates passing through the narrow capillaries leads to a significant decrease in the velocity of the capillary blood flow, which can be explained by the increased viscosity of the whole blood and decreased deformability of RBCs. Also, for the group of patients, a statistically significant increase in the rate of RBC aggregation and the hydrodynamic strength of aggregates, RBC aggregation and disaggregation forces were observed compared to the control group.

Laser Aggregometry Assessment of Blood Microrheology in a Slit Fluidic Channel Covered With Endothelial Cells.

The blood rheology in vitro in glass or plastic microfluidic chips is different from that in vivo in blood vessels with similar geometry. Absence of vascular endothelium is suggested to cause these discrepancies. This work aims to perform in vitro measurements of blood microrheologic parameters in a slit microfluidic channel covered with endothelial cells (HUVEC).

Influence of optical clearing agents on the scattering properties of human nail bed and blood microrheological properties: In vivo and in vitro study.

Optical clearing agents (OCAs) are substances that temporarily modify tissue's optical properties, enabling better imaging and light penetration. This study aimed to assess the impact of OCAs on the nail bed and blood using in vivo and in vitro optical methods. In the in vivo part, OCAs were applied to the nail bed, and optical coherence tomography and optical digital capillaroscopy were used to evaluate their effects on optical clearing and capillary blood flow, respectively.

Forces of interaction of red blood cells and endothelial cells at different concentrations of fibrinogen: Measurements with laser tweezers in vitro.

Blood microrheology depends on the constituents of blood plasma, the interaction between blood cells resulting in red blood cell (RBC) and platelets aggregation, and adhesion of RBC, platelets and leukocytes to vascular endothelium. The main plasma protein molecule -actuator of RBC aggregation is fibrinogen. In this paper the effect of interaction between the endothelium and RBC at different fibrinogen concentrations on the RBC microrheological properties was investigated in vitro.

Correlation between the Capillary Blood Flow Characteristics and Endothelium Function in Healthy Volunteers and Patients Suffering from Coronary Heart Disease and Atrial Fibrillation: A Pilot Study.

Coronary heart disease (CHD) and atrial fibrillation (AF) pose significant health risks and require accurate diagnostic tools to assess the severity and progression of the diseases. Traditional diagnostic methods have limitations in providing detailed information about blood flow characteristics, particularly in the microcirculation. This study's objective was to examine and compare the microcirculation in both healthy volunteers and patient groups with CHD and AF.

Multimodal Diagnostics of Microrheologic Alterations in Blood of Coronary Heart Disease and Diabetic Patients.

Coronary heart disease (CHD) has serious implications for human health and needs to be diagnosed as early as possible. In this article in vivo and in vitro optical methods are used to study blood properties related to the aggregation of red blood cells in patients with CHD and comorbidities such as type 2 diabetes mellitus (T2DM). The results show not only a significant difference of the aggregation in patients compared to healthy people, but also a correspondence between in vivo and in vitro parameters.

Assessment of Fibrinogen Macromolecules Interaction with Red Blood Cells Membrane by Means of Laser Aggregometry, Flow Cytometry, and Optical Tweezers Combined with Microfluidics.

An elevated concentration of fibrinogen in blood is a significant risk factor during many pathological diseases, as it leads to an increase in red blood cells (RBC) aggregation, resulting in hemorheological disorders. Despite the biomedical importance, the mechanisms of fibrinogen-induced RBC aggregation are still debatable. One of the discussed models is the non-specific adsorption of fibrinogen macromolecules onto the RBC membrane, leading to the cells bridging in aggregates.

Optical assessment of alterations of microrheologic and microcirculation parameters in cardiovascular diseases.

In this work, we compare the blood aggregation parameters measured in vitro by laser aggregometry and optical trapping techniques in blood samples with the parameters of blood rheology measured in vivo by digital capillaroscopy in the nail bed capillaries of patients suffering from the hypertension and coronary heart disease. We show that the alterations of the parameters measured in vivo and in vitro for patients with different stages of these diseases are interrelated. Good agreement between the results obtained with different techniques, and their applicability for the diagnostics of abnormalities of rheological properties of blood are demonstrated.