Search results for "VISCOSITY"

Prevention of ischemic-type biliary lesions by arterial back-table pressure perfusion

2003

Abstract Ischemic-type biliary lesions (ITBLs) lead to considerable morbidity after orthotopic liver transplantation (OLT). The exact pathogenesis is unknown. We tested the hypothesis that insufficient perfusion of biliary arterial vessels might be responsible for ITBLs. This could be prevented by improved perfusion techniques. Since February 2000, we performed a controlled study using arterial back-table pressure perfusion (AP) to achieve reliable perfusion of the biliary-tract capillary system, which may be impaired by the high viscosity of University of Wisconsin solution. We retrospectively analyzed 190 OLTs performed between September 1997 and July 2002 with regard to ITBLs. One hundre…

Solid cheese consumption: Quantification of oral coating

2011

International audience; Mouth coating, defined as the residual food that sticks to the oral surface after food ingestion, plays an important role in both the delivery of food components and mouth feel and after-feel perceptions. The aim of this work was to adapt a rapid and simple instrumental method to the quantification of food remaining after the in vivo ingestion of a solid food. This method was investigated in 12 non-trained subjects who consumed four melted cheeses differing in terms of their fat and water contents. Mouth coating was determined by fluorescence measurements using curcumin, an oil-soluble dye that had been added to the cheeses during their preparation. The results obtai…

Reduction in blood viscosity at low rates of shear by surface active substances: a new hemorheologic phenomenon

1968

Haemorheological profile in congenital afibrinogenemia and in congenital dysfibrinogenemia: A clinical case report

2019

Although the inherited quantitative and qualitative disorders of fibrinogen are rare, in the course of time patients may develop complications including episodes of arterial and venous thrombosis. It can be useful to complete the laboratory assessment of these clinical conditions with the evaluation of the haemorheological profile. The data obtained from this study showed that congenital afibrinogenemia was characterized by a primary plasma hypoviscosity, whereas congenital dysfibrinogenemia by a primary plasma hyperviscosity. Both these haemorheological alterations may concur, with different mechanisms, to the pathogenesis of thrombotic vascular complications.

Viscosity of the elbow flexor muscles during maximal eccentric and concentric actions.

1996

The aim of the present study was to estimate the damping coefficient (B factor) of the elbow flexor muscles during both eccentric and concentric muscle actions. We used a muscle model consisting of a viscous damper associated in parallel with a contractile component, both in series with an elastic component. The viscous damper allowed the concentric loss and the eccentric gain of force to be modelled. Eight volunteer subjects performed maximal eccentric and concentric elbow movements on an isokinetic dynamometer at angular velocities of 0.52, 1.04 and 2.09 rad*s(-1). Torques at an elbow joint angle of 90 degrees were recorded. Electromyogram (EMG) signals from the belly of the right elbow f…

Analysis of the Blood Viscosity Behavior in the Sicilian Study on Juvenile Myocardial Infarction

2018

Considering the role of hemorheology in coronary circulation, we studied blood viscosity in patients with juvenile myocardial infarction. We examined whole blood viscosity at high shear rate using the cone-on-plate viscosimeter Wells-Brookfield ½ LVT and at low shear rate employing a viscometer Contraves LS30 in 120 patients (aged <46 years) with myocardial infarction, at the initial stage and subsequently 3 and 12 months after. At the initial stage, patients had an increased whole blood viscosity in comparison to normal controls. This hemorheological profile was not influenced by the cardiovascular risk factors, nor by the extent of coronary lesions, even if some differences were evide…

The distribution of whole blood viscosity, its determinants and relationship with arterial blood pressure in the community: cross-sectional analysis …

2015

Background: Blood viscosity has a role in modulating cardiovascular homeostasis; changes in this parameter have been associated with cardiovascular mortality and morbidity. However, it remains unclear whether these changes are (1) involved in the pathophysiology of disease, (2) an epiphenomenon, or (3) the expression of counterregulatory mechanisms. We report data on the normal values of blood viscosity and its association with cardiovascular risk factors, prevalent cardiovascular disease, and blood pressure in a large population-based cohort study. Methods and results: Viscosity was calculated using validated formulae and its associations were explored in 15,010 participants (mean 55.0, mi…

Lack of association between hemorheological alterations and upper-extremity deep vein thrombosis.

2009

Introduction: There is an association between rheological alterations and lower extremity deep vein thrombosis, although no research has been carried out regarding the possible influence of rheological alterations in the development of venous thrombosis in the upper limbs. Materials and methods: We have determined in 54 patients (23 male, 31 female; aged 35 ± 11 years) with primary upper extremity deep vein thrombosis (UEDVT), and in a well matched control group of 87 subjects (41 male, 46 female; aged 36 ± 12 years) the rheological profile (blood viscosity, plasma viscosity, fibrinogen, erythrocyte aggregation, erythrocyte de- formability) along with plasma lipids (total cholesterol and tr…

Erythrocyte deformability evaluated by laser diffractometry in polycythemia vera.

2012

We evaluated the erythrocyte deformability in a group of subjects with polycythemia vera (PV) using a Rheodyn-SSD Laser Diffractometer, at the shear stresses of 6, 12, 30 and 60 Pa. Our data showed a significant decrease of red cell deformability, expressed as elongation index (EI), in PV subjects compared with normal controls. These results suggest that the hyperviscosity syndrome accompanying this myeloproliferative disease may be considered a mixed form, resulting from the association of a polycythemic condition with a sclerocythemic disorder.

Short-Term Prognosis of Juvenile Myocardial Infarction

2016

In our early research regarding the hemorheological pattern in patients with acute myocardial infarction (AMI) with a mean age of 61.45 + 10.99 years, we showed that the major hemorheological parameters were almost normalized 2 weeks after the acute event. In the last decade, we focused on hemorheological parameters in juvenile myocardial infarction (JMI), defined as AMI in patients aged 45 years, in the ‘‘Sicilian study on juvenile myocardial infarction’’. Juvenile myocardial infarction is responsible for 2% to 10% of all cases with AMI in different surveys. Juvenile myocardial infarction presents a typical pattern of risk factors and shows clinical, angiographic, and prognostic characteri…