ABSTRACT
The physiological characteristics of skin blood flow can be described in terms of the hemodynamic indices (HI). The HI is derived from the laser speckle characteristics, which are governed by the cutaneous blood flow. A miniaturized dynamic light-scattering sensor was used to measure the speckle pattern from the finger root. Three groups of subjects from 15 to 25 years of age were tested. The first group included subjects who are actively engaged in sport activities; the second group included subjects with low level of physical activity; and the third group included healthy controls with moderate physical activity. The HI parameters were measured prior to and after the performance of a determined physical load. As a marker of cardiovascular fitness (CVF), we used the postload decay rate of HI. We found that the hemodynamic response to the physical load provides a statistically significant correlation with the postload heart rate decay. It was also found that postocclusion increase of the arterial HI is more prominent in the group with higher physical activity. These results indicate that hemodynamic indices can be used as an additional marker for cardiovascular fitness level.
Subject(s)
Dynamic Light Scattering/methods , Hemodynamics/physiology , Physical Fitness/physiology , Signal Processing, Computer-Assisted , Adolescent , Adult , Humans , Pulse , Skin/blood supply , Young AdultABSTRACT
A novel noninvasive method of an assessment of the hemostasis system and the vascular walls functioning is proposed. This method is based on the methodology of dynamic light scattering (DLS). New index SKF, which is derived from the previously established relationship between the intravascular mobility of the erythrocytes and the biological age, has been introduced. We demonstrated that the degree of the severity of the diseases correlates with the SKF index. More specifically, an increased value of the SKF index was found for the groups with cardio-vascular, oncological diseases and diabetes mellitus. In addition we provided evidences that the SKF index depends on the blood and plasma viscosity related to activity stage of the hemostasis system as well as on the functioning of the vascular walls.
Subject(s)
Blood Vessels/physiology , Health Status Indicators , Hemostasis , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Blood Vessels/pathology , Cardiovascular Diseases/epidemiology , Case-Control Studies , Child , Child, Preschool , Diabetes Mellitus/epidemiology , Erythrocytes/physiology , Female , Hemorheology , Humans , Infant , Light , Male , Middle Aged , Neoplasms/epidemiology , Scattering, Radiation , Young AdultABSTRACT
The article considers the noninvasive technique of analysis of aggregation activity of thrombocytes and formation of leukocytic-erythrocytic-thrombocytic aggregates and some particular indicators of hemostasis system. The speckle-analysis of characteristics of coherent light dispersion from surface of erythrocytes moving in artificially isolated vessel section. The study established high correlation ratio between light dispersion index and spontaneous ADP-, adrenalin- and collagen-induced aggregation of thrombocytes, formation of leukocytic-erythrocytic and thrombocytic-erythrocytic aggregations. The established facts permits to consider that analysis noninvasive technique makes it possible to estimate approximately the aggregation activity of blood corpuscles.
Subject(s)
Blood Platelets , Cell Aggregation/drug effects , Erythrocytes , Leukocytes , Adenosine Diphosphate/pharmacology , Blood Platelets/cytology , Blood Platelets/drug effects , Collagen/pharmacology , Epinephrine/pharmacology , Erythrocytes/cytology , Erythrocytes/drug effects , Hemostasis/physiology , Humans , Leukocytes/cytology , Leukocytes/drug effectsABSTRACT
A non-invasive method for the study of platelet aggregation and formation of leukocyte-erythrocyte-platelet aggregates as well as certain hemostatic parameters is proposed. The method is based on the speckle-analysis of coherent light scattering from the surface of erythrocytes moving in an artificially isolated vessel segment. It was shown that light scattering index significantly correlated with ADP-, adrenalin-, or collagen-induced platelet aggregation, with the formation of leukocyte-erythrocyte or platelet-erythrocyte aggregates, and with the levels of fibrinogen, soluble fibrin-monomer complexes and related parameters. It is concluded that the proposed method for the study of hemostatic system can be used to roughly evaluate intensity of intravascular blood coagulation and probability of thrombosis.
Subject(s)
Blood Platelets/metabolism , Erythrocyte Aggregation/physiology , Erythrocytes/metabolism , Hemostasis/physiology , Leukocytes/metabolism , Platelet Aggregation/physiology , Thrombosis/diagnosis , Adolescent , Adult , Aged , Blood Chemical Analysis/methods , Blood Coagulation , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Thrombosis/blood , Young AdultABSTRACT
We have conducted a study on a large group of healthy and sick subjects and have demonstrated that a new index of coagulativety (SKF), based on measurement of the laser speckle signal from the finger root, correlates with chronological age ranging from 1 to 85 years old. The kinds of non-invasive measurements were obtained during two measurement sessions: one with the application of over-systolic occlusion and another without application of the occlusion. The very significant correlation with age was noted both during the stasis stage and during the non-occluding stage. We observed a higher SKF index in sick subjects, correlating directly with severity of illness. We speculated that the observed phenomena are caused by temporarily fluctuations in local blood viscosity associated with interactions of the Red Blood Cells and endothelial cells.
