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Disorders in tHemostasis System and Changes in the Rheological Properties of the Blood in Ischemic Heart Disease and Diabetes Mellitus Patients
Published in E.I. Sokolov, Obesity and Diabetes Mellitus, 2020
In the previous chapter, we noted the considerable changes in the lipoprotein content in DM — this concerned a growth in the level of VLDLP, LDLP, apo-B, etc. It is doubtless that these factors also affect the growth in the blood viscosity. Our investigations proved that the increase in the velocity of the blood in DM patients is affected considerably by a high content of cholesterol, triglycerides, cholesterol of the low-density and very low-density lipoproteins, and fibrinogen. Electron microscopy noted the adsorption of these macromolecules on the surface of erythrocytes with a relevant drop in the negative membrane charge of the blood cells. It also noted adhesion of the erythrocytes to the endothelium of the vessels and erythrocyte aggregation.
Red Cell Aggregation and Yield Stress
Published in Gordon D. O. Lowe, Clinical Blood Rheology, 2019
Since this paper was originally written, a number of developments have taken place in the technology for quantitating rouleaux formation. A review of these has been given by Stoltz et al.,75 and Lacombe and Lelievre76 have reviewed a variety of parameters for estimating erythrocyte aggregation that can be derived from Couette viscometry. A paper has also appeared77 that compares the performances of the Myrenne Erythrocyte Aggregometer, Paar Oscillating Capillary Rheometer, and Erythrocyte Sedimentation Rate Test with techniques based on direct microscopic observation and low shear rate viscometry. The correlations between the responses of these techniques were generally very good but the suspensions studied were simple, the erythrocytes being suspended in physiological buffer containing only fibrinogen as aggregating agent. What is still needed is a comprehensive comparison of these methodologies applied to blood and especially to pathological samples.
The role of biochemistry and serology in pain diagnosis
Published in Harald Breivik, William I Campbell, Michael K Nicholas, Clinical Pain Management, 2008
Over many years, the erythrocyte sedimentation rate (ESR) has been the most widely used marker of inflammation or infection. The level reflects the degree of erythrocyte aggregation and is the measured fall or setting in a vertical column (usually a 200-mm glass tube) of red blood cells within one hour at room temperature (the classical Westergren’s method).32 The degree of sedimentation is dependent on the number and shape of the erythrocytes, as well as serum proteins, that influence the tendency to aggregate erythrocytes.33 Asymmetric, charged proteins decrease the natural tendency of erythrocytes to repel each other, leading to red blood cell aggregation and rouleaux formation. The acute phase protein fibrinogen is the most prevalent of the asymmetric acute phase proteins and has the greatest effect on ESR levels. ESR will thus indirectly reflect the acute phase reaction. The immunoglobulins, especially the pentamer IgM as well as high amounts of IgG, will also increase red blood cell aggregation and cause increased ESR. Anemia may cause increased,34 and polycythemia decreased,33 levels of ESR, and in addition, alterations in size and shape of erythrocytes may physically interfere with the rouleaux formation. ESR is thus an unspecific marker of inflammation, infection, malignancies, and necrosis. However, during pregnancies, there are normally increased levels of fibrinogen and ESR will thus be elevated.35 Under the age of 50 years, the upper limits of normal ESR are 15 mm per hour for males and 20 mm per hour for females, while over the age of 50 years, the levels are 20 mm per hour and 30 mm per hour, respectively.36
Contemporary review of the causes and differential diagnosis of sudden sensorineural hearing loss
Published in International Journal of Audiology, 2020
Pregnancy may play a precipitating role for inducing SD, since elevated oestrogen raises the circulating cholesterol levels during pregnancy, thereby increasing the risk of vascular insufficiency (Tettenborn 2012). The progesterone level also elevates near the end of the third trimester, enhancing venous distensibility and allowing for venous stasis in the hyperdynamic state of pregnancy. Thus, increased sex hormone levels may cause thrombogenic risk and interrupt cochlear microcirculation, leading to the development of SD (Wang and Young 2006). Additionally, declined erythrocyte deformability and increased erythrocyte aggregation accompanied by increased plasma viscosity are also identified during antepartum period. Furthermore, pregnant women are at an increased risk of stroke due to a number of different factors that alter body’s cardiovascular hemodynamic and coagulation mechanisms (Grear and Bushnell 2013). Therefore, maintenance of adequate microcirculation in the uteroplacental unit during normal gestation is essential (Bollini et al. 2005).
Hemorheological dysfunction in cardiac syndrome X
Published in Acta Cardiologica, 2018
Emine Kilic-Toprak, Olga Yaylali, Yalin Tolga Yaylali, Yasin Ozdemir, Dogangun Yuksel, Hande Senol, Tarık Sengoz, Melek Bor-Kucukatay
Hemodynamic consequences of RBC aggregation predict a negative correlation between the extent of erythrocyte aggregation and tissue perfusion. This correlation has been demonstrated to be especially relevant in areas of the circulatory system with relatively lower effective shear forces (e.g. coronaries and venous vessels). The influence of RBC aggregation on flow resistance has been suggested to play role in flow dynamics and fluid exchange: RBC aggregates existing on the arterial side of the circulatory system need to be dispersed into individual RBC in order for cells to pass through the terminal microvasculature. This disaggregation process has an energy cost and hence tends to increase the flow resistance of the microcirculation [24]. Circulatory problems of various organs have been reported to be characterised by increased RBC aggregation including myocardial ischaemia and infarction [25,26], peripheral vascular diseases [27] and angina [25]. It has also been argued that the enhanced RBC aggregation in such disorders might contribute to the pathophysiology [22]. A prognostic value has also been attributed to RBC aggregation in patients with unstable angina [28]. As mentioned before, CSX is characterised by myocardial ischaemia and angina [1–3,5–7]. Supported by previous reports exploring the association of augmented erythrocyte aggregation and myocardial perfusion, the elevated RBC aggregation found in CSX in our study suggests that this hemorheological disturbance may contribute to the clinical manifestation of CSX.
Immunity and inflammation predictors for short-term outcome of stroke in young adults
Published in International Journal of Neuroscience, 2018
Xiaoqing Zhou, Fang Yu, Xianjing Feng, Junyan Wang, Zhibin Li, Qiong Zhan, Jian Xia
Besides, we found the predictive value of decreased A/G levels in poor outcome of acute IS in our study. A/G ratio is one of the biochemical markers that could reflect the severity of many chronic diseases like diabetes mellitus, and has the same implication as erythrocyte sedimentation rate. As increased blood viscosity, which is inversely proportional to A/G, is one of the mechanisms of IS. It may influence erythrocyte aggregation by increasing low shear viscosity and decreasing erythrocyte sedimentation under no-flow conditions. Albumin has multifaceted intravascular effects; it constitutes a major antioxidant defense against oxidizing agents. Serum albumin level is one of the biochemical markers of nutritional status. It was shown that protein-energy malnutrition after acute stroke is a risk factor for poor outcome and could worsen the prognosis by decreasing cellular immunity. However, no significant interaction between serum albumin levels and different outcome or severity of IS was found in our study. A likely explanation of the discrepancies between these results is that our patients were younger, since patients aged 85 years or older showed some peculiar clinical features and poorer outcome, including higher in-hospital mortality and moderate and severe neurological deficit at hospital discharge than younger patients [34]. It has been reported that albumin is prognostic factor in elderly patients with acute ischemic disease. When albumin is elevated by 1 g/L, the risk of poor prognosis is reduced by 27% [35]. Albumin levels only have significant effects on the prognosis of elderly people; it might suggest that the nutritional status influences more on the severity of stroke and the rehabilitation of neurological function of elderly people. Indeed, A/G ratio was different between groups.