Search results for "Viscosity."
showing 10 items of 537 documents
Plasma Viscosity and NLR in Young Subjects with Myocardial Infarction: Evaluation at the Initial Stage and at 3 and 12 Months
2018
In the “Sicilian study on juvenile myocardial infarction,” we had evaluated plasma viscosity (PV) and neutrophil/lymphocyte ratio (NLR) in patients with acute myocardial infarction (AMI) at the age of ⩽45 years. Now, we examined the relationship between these 2 parameters in 120 subjects (109 men and 11 women) aged ⩽45 years with recent AMI. The patients were classified according to the number of cardiovascular risk factors, the electrocardiographic criteria (ST-segment elevation myocardial infarction [STEMI] or non-ST-segment elevation myocardial infarction [NSTEMI]), and the extent of coronary stenosis, evaluated with coronary angiography. On fasting venous blood, we measured PV at the sh…
Spectroscopic and Structural Investigation of the Confinement of D and L Dimethyl Tartrate in Lecithin Reverse Micelles
2009
The confinement of D and L dimethyl tartrate in lecithin reverse micelles dispersed in cyclohexane has been investigated by FT-IR, polarimetry, electronic and vibrational circular dichroism (ECD and VCD), 1H NMR, and small-angle X-ray scattering (SAXS). Measurements have been performed at room temperature as a function of the solubilizate-to-surfactant molar ratio (R) at fixed lecithin concentration. The analysis of experimental data indicates that the dimethyl tartrate molecules are solubilized within reverse micelles in proximity to the surfactant head groups in the same way for the D and L forms. The encapsulation of dimethyl tatrate within lecithin reverse micelles involves changes in i…
Data from: How do cuticular hydrocarbons evolve? Physiological constraints and climatic and biotic selection pressures act on a complex functional tr…
2016
Cuticular hydrocarbons (CHCs) cover the cuticles of virtually all insects, serving as a waterproofing agent and as a communication signal. The causes for the high CHC variation between species, and the factors influencing CHC profiles, are scarcely understood. Here, we compare CHC profiles of ant species from seven biogeographic regions, searching for physiological constraints and for climatic and biotic selection pressures. Molecule length constrained CHC composition: long-chain profiles contained fewer linear alkanes, but more hydrocarbons with disruptive features in the molecule. This is probably owing to selection on the physiology to build a semi-fluid cuticular layer, which is necessa…
Abnormal Haemostasis and Blood Viscosity in Malignant Hypertension
1984
SummaryWe have previously shown abnormalities of haemostasis suggestive of intravascular coagulation in patients with malignant hypertension, a condition associated with retinopathy and renal fibrin deposition. To determine whether such abnormalities are specific to malignant hypertension, we have measured several haemostatic and haemorheological variables in 18 patients with malignant hypertension (Group 1), 18 matched healthy controls (Group 2), and 18 patients with non-malignant hypertension (Group 3) matched for renal pathology, blood pressure and serum creatinine with Group 1. Both Groups 1 and 3 had increased mean levels of fibrinogen, factor VIIIc, beta-thrombo- globulin, plasma visc…
Healon5 viscoadaptive formulation: Comparison to Healon and Healon GV
2001
Abstract Purpose To compare the rheological characteristics of a viscoadaptive viscoelastic formulation with those of 2 standard ophthalmic viscosurgical devices (OVDs). Setting Department of Ophthalmology, Johannes Gutenberg-University, and Max Planck-Institute for Polymer Research, Mainz, Germany. Methods An independent comparative study of 3 OVDs of sodium hyaluronate (Healon®, Healon GV®, and Healon®5) was performed using the Advanced Rheometric Expansion System to analyze rheologic behavior (eg, dynamic frequency dependence of the complex viscosity) as well as rheological parameters (eg, viscosity at zero shear rate, pseudoplasticity, relaxation time, elastic and viscous modulus). Resu…
Clinical conditions responsible for hyperviscosity and skin ulcers complications
2017
In this brief review, we have examined some clinical conditions that result to be associated to an altered hemorheological profile and at times accompanied by skin ulcers. This skin condition may be observed in patients with the following condtions, such as primary polycythemic hyperviscosity (polycythemia, thrombocytemia) treated with hydroxyurea, primary plasma hyperviscosity (multiple myeloma, cryoglobulinemia, cryofibrinogenemia, dysfibrinogenemia, and connective tissue diseases), primary sclerocythemic hyperviscosity (hereditary spherocytosis, thalassemia, and sickle cell disease). In addition, it may be present in patients with secondary hyperviscosity conditions such as diabetes mell…
Haemorheological components in the pre-geriatric and geriatric age range in a randomly selected Western Sicily population sample (Casteldaccia study)
1993
{Received 24.8.1992; accepted 7.12.1992} On a randomly selected western Sicily population sample (Casteldac cia Study: 600 subjects; 300 males and 300 females) of an age range from 40 to 79 years, were determined: Haematocrit (Htc) , blood vi scosity, plasma viscosity, filterability of whole blood and fibrinogen. Par ticipation was 97%, being 582 subjects (M = 287, F = 295). All the parameters measured showed a progressive increase with age and si gnificant differences were found between male and female subjects: Htc and blood viscosity were higher in male subjects (p < 0.01), while plasma viscosity, whole blood filterability and fibrinogen were higher in female subjects (p < 0.05). In …
Haemodynamic effects of long-term administration of sildenafil in normotensive pregnant and non-pregnant rats
2011
Please cite this paper as: Pellicer B, Herraiz S, Cauli O, Rodrigo R, Asensi M, Cortijo J, Serra V, Morcillo E, Felipo V, Simon C, Pellicer A. Haemodynamic effects of long-term administration of sildenafil in normotensive pregnant and non-pregnant rats. BJOG 2011;118:615–623. Objective To determine the effects of chronic administration of sildenafil citrateon healthy pregnant rats. Design In vivo animal experimental study. Setting Fundacion IVI–Instituto Universitario IVI, Valencia, Spain. Sample Pregnant and non-pregnant Wistarrats exposed to chronic administration of sildenafil. Methods Placental cross-barrier and feto-maternal relationship levels, maternal blood pressure, and haemody…
Vascular atherosclerotic disease: evaluation of the whole-blood filterability and red cell membrane microrheological pattern after intravenous admini…
1990
SummaryA study was carried out in 10 patients with vascular atherosclerotic disease to investigate the effects of a single dose of 300 mg pentoxifylline, given by intravenous infusion over 30 minutes, on various macrorheological and nzicrorheological parameters. Measurements were made at baseline, at the end of the intravenous infusion and again 30 minutes later of whole-blood filterability, erythrocyte membrane fluidity (using pyrene as probe) and transverse fluidity gradient (using fluorescent fatty acids as probes). The results showed that there was a significant variation in whole-blood filterability and the red cell membrane fluidity gradient after pentoxifylline. No difference, howeve…
High Output Heart Failure in Multiple Myeloma: Pathogenetic Considerations.
2022
The high output heart failure is a clinical condition in which the systemic congestion is associated to a high output state, and it can be observed in a non-negligible percentage of hematological diseases, particularly in multiple myeloma, a condition in which the risk of adverse cardiovascular events may increase, with a worse prognosis for patients. For this reason, though an accurate literature search, we provided in this review a complete overview of different pathogenetic mechanisms responsible for high output heart failure in multiple myeloma. Indeed, this clinical finding is present in the 8% of multiple myeloma patients, and it may be caused by artero-venous shunts, enhanced angioge…