Sufficient organ blood flow of healthy newborn babies is maintained by relatively low systemic blood pressure. Premature infants are at an increased risk of systemic hypotension, often but not obviously, resulting in hypoperfusion of the cerebral, renal and intestinal vascular beds. Maintaining a stable blood pressure in preterm babies is ...

OBJECTIVE: To explore the reliability of examining the external iliac artery (EIA) at 11+0 to 13+6 weeks of gestation with Doppler ultrasound and its relationship with maternal characteristics and uterine artery blood flow. STUDY DESIGN: Cross-sectional study of 451 pregnant women undergoing an ultrasound scan in the first trimester. Mean ...

OBJECTIVE: Flow-mediated dilation (FMD) is used to evaluate endothelial functions. Computer-assisted analysis utilizing edge detection permits continuous measurements along the vessel wall. We have developed a new fully automated software program to allow accurate and reproducible measurement. METHODS: FMD has been measured and analyzed in 18 coronary artery disease (CAD) ...

The precise mechanisms that give rise to the blood-oxygen-level-dependent (BOLD) activation differences that accompany age-related cognitive slowing remain fundamentally unknown. We sought to isolate the origin of age-related BOLD changes by comparing blood-flow and oxygen-metabolic constituents of the BOLD response using dual-echo arterial spin labeling during visual stimulation and CO(2) ...

Simple chronic transfusion therapy (CTT) is a mainstay for stroke prophylaxis in sickle cell anemia, but its effects on hemodynamics are poorly characterized. Transfusion improves oxygen-carrying capacity, reducing demands for high cardiac output. While transfusion decreases factors associated with vasoocclusion, including percent hemoglobin (Hb)S, reticulocyte count, and circulating cell-free Hb, ...

OBJECTIVES: To assess the reliability of prothrombin time and activated partial thromboplastin time results generated from citrated whole blood samples following short-term storage at room temperature. METHODS: Clotting times were measured in blood samples from 40 dogs that showed a variety of clinical signs. Before measurement of prothrombin time and ...

We read the interesting paper recently published by Wilhelm et al (1) . Measured blood concentrations of cyclosporine (CsA) reported in figure 2 seems very high with regards of the daily dose administered. This could be due to the way of blood sampling in some patients.

Time-resolved three-dimensional flow measurements are limited by long acquisition times. Among the various acceleration techniques available, k-t methods have shown potential as they permit significant scan time reduction even with a single receive coil by exploiting spatiotemporal correlations. In this work, an extension of k-t principal component analysis is proposed ...

Many different surgical and non-surgical techniques are used for the treatment of temporomandibular joint (TMJ) hypermobility. One of these methods is autologous blood injection into the TMJ. The fate of the autologous blood used for treatment of recurring condylar dislocation is still not completely understood. The authors used 12 pigs ...

International studies have shown blood lead at levels causing health concern in recreational indoor shooters. We hypothesized that Danish recreational indoor shooters would also have a high level of blood lead, and that this could be explained by shooting characteristics and the physical environment at the shooting range. This was ...

BACKGROUND: The frequency of Human T lymphotropic Virus-1 (HTLV 1) is 2-3% in the general population and 0.7% in blood donors in northeast Iran. It is very important that we recognize the contributing factors in the pathogenesis of this virus. There are many reports that show that susceptibility to some ...

This study investigates the frequency of Torque teno virus (TTV) infection in 150 blood donors and 77 patients requiring haemodialysis in southern Brazil. Plasma samples were screened for TTV DNA using polymerase chain reaction (PCR). The prevalences of TTV among blood donors and patients requiring haemodialysis were 73.3% and 68.8%, ...

ABSTRACT Background: Increases in blood vessel density and vascular area are now recognized as important features of remodeled airways in asthma. However, the time sequence for these vascular changes and whether they resolve in the absence of continued antigenic exposure is not well elucidated. The aim of the present study ...

Red blood cell (RBC) transfusion is indicated to improve oxygen delivery to tissue, and for no other purpose. We have come to appreciate that donor RBCs are fundamentally altered during processing and storage in a manner that both impairs oxygen transport efficacy and introduces additional risk by perturbing both immune ...

The development of anemia after birth in very premature, critically ill newborn infants is a universal well-described phenomenon. Although preventing anemia in this population, along with efforts to establish optimal red blood cell (RBC) transfusion and pharmacologic therapy continue to be actively investigated, the present review focuses exclusively on nonpharmacological ...

Perioperative optimization of spatially resolved near-infrared spectroscopy determined cerebral frontal lobe oxygenation (scO2) may reduce postoperative morbidity. Norepinephrine is routinely administered to maintain cerebral perfusion pressure and, thereby, cerebral blood flow, but norepinephrine reduces the scO2. We hypothesized that norepinephrine-induced reduction in scO2 is influenced by cutaneous vasoconstriction. Fifteen healthy ...

Estimation of instantaneous flow in rotary blood pumps (RBPs) is important for monitoring the interaction between heart and pump and eventually the ventricular function. Our group has reported an algorithm to derive ventricular contractility based on the maximum time derivative (dQ/dt(max) as a substitute for ventricular dP/dt(max) ) and pulsatility ...

What is believed to be the first fully integrated two-dimensional complementary metal oxide semiconductor (CMOS) imaging array for laser Doppler blood flow imaging is demonstrated. The sensor has 64×64 pixels and includes both analog and digital on-chip processing electronics. This offers several potential advantages over commercial sensors as the processing ...

Mechanical circulatory assist devices that provide temporary support in heart failure patients are needed to enable recovery or provide a bridge to decision. Minimizing risk of blood damage (i.e., hemolysis) with these devices is critical, especially if the length of support needs to be extended. Hematologic responses of the RotaFlow ...

The study aimed to examine 1) the validity of the nine-factor flow model in tennis competition; 2) differences in flow state between athletes who won or lost their competition match; 3) the link between flow and subjective performance; and 4) flow dimensions as predictors of performance outcome The sample consisted ...

To evaluate the feasibility of conjunctival hemodynamic measurements based on assessment of reproducibility, validity, and response to acute hypotension. Image sequences of the conjunctival microvasculature of rabbits were captured using a slit lamp biomicroscope under a steady-state condition, after topical administration of phenylephrine, and after intravenous administration of esmolol. Venous ...

BACKGROUND: The safety of the blood supply is ensured through several procedures from donor selection to testing of donated units. Examination of the donor deferrals at different centers provides insights into the role that deferrals play in transfusion safety. STUDY DESIGN AND METHODS: A cross-sectional descriptive study of prospective allogeneic ...

BACKGROUND: After cardiac surgery, red blood cell (RBC) transfusion may improve systemic hemodynamics and thereby microvascular blood flow and O(2) delivery (DO(2) ). STUDY DESIGN AND METHODS: In a nonrandomized prospective observational study on post-cardiac surgery patients, systemic hemodynamics and microvascular blood flow, vascular density (sidestream dark-field imaging), hemoglobin (Hb) ...

Afghanistan is a country with population of over 28million. The long term conflicts have devastated country's qualified resources including human resources. ANBSTS was established by MoPH as the country national blood service. Currently in addition to central and regional blood centers of ANBSTS many other hospitals have their own transfusion ...

Blood color of dialysis patients can be seen routinely. Darkened blood color is often observed in critically ill patients generally because of decreased oxygen saturation, but little is known about the other factors responsible for the color intensity. In addition, quantitative blood color examination has not been performed yet. Therefore, ...

Long-term rotary left ventricular assist devices (LVADs) are increasingly employed to bridge patients with end-stage heart failure to transplant or as a destination therapy. Significant recent device development has increased patient support times, shifting further development focus toward physiologically sensitive control of the pump operation. Sensorless control of these devices ...

To evaluate the sources of variation influencing the microvascularization parameters measured by dynamic contrast-enhanced ultrasonography (DCE-US). Firstly, we evaluated, in vitro, the impact of the manual repositioning of the ultrasound probe and the variations in flow rates. Experiments were conducted using a custom-made phantom setup simulating a tumor and its ...

ABSTRACT: OBJECTIVES: Although blood group 0 is associated with a reduced risk of pancreatic cancer, little is known about the role of AB0 blood group antigens in disease progression. We assessed the prognostic relevance of AB0 blood status in a large cohort of patients with resected pancreatic cancer. METHOD: S: ...

Background and Objectives  Hepatitis E virus (HEV) infection is emerging as a potential new threat to blood safety after several cases of transfusion-transmission were reported from non-epidemic countries. On the basis of seroprevalence data, HEV is endemic in Ghana where poor sanitary conditions and regular flooding are prevalent. However, no ...

Cerebral hemodynamic impairment has come under examination over the years as an independent cause for cognitive dysfunction, but only recently has the advance of imaging and ultrasound technology permitted a fuller investigation of physiopathology. Beyond the impact of fixed structural lesions such as infarction and white matter hyperintensities, hemodynamic dysfunction, ...

One of the main goals of hemodynamic support is to preserve tissue perfusion. However issue perfusion is related more to microvascular perfusion than aortic blood flow. Monitoring the microcirculation has long been difficult. Recent technologic advances have made feasible monitoring of the microcirculation at bedside of critically ill patients. In ...

OBJECTIVE: The purpose of this study was to evaluate alterations in flow patterns in thoracic aortic dissections using 4-dimensional, flow-sensitive magnetic resonance imaging. METHODS: This prospective study was conducted at 2 academic tertiary referral medical centers. Thirteen 4-dimensional flow magnetic resonance imaging studies were performed in 12 subjects (4 female, ...

BACKGROUND:: Assessment of the vasculature is critical for overall success in cranial vascular neurological surgery procedures. While several methods of monitoring cortical perfusion intraoperatively are available, not all are appropriate or convenient in a surgical environment. Recently, two optical methods of care have emerged that are able to obtain high ...

The healthcare system relies widely on biochemical information obtained from blood sample extracted via hypodermic needles, despite the invasiveness and pain associated with this procedure. Therefore, an alternative micro-scale needle for minimally invasive blood sampling is highly desirable. Traditional fabrication techniques to create microneedles do not generate needles with the ...

A computer simulation model based on an analytic flow velocity distribution is proposed to generate Doppler ultrasound signals from pulsatile blood flow in the vessels with various stenosis degrees. The model takes into account the velocity field from pulsatile blood flow in the stenosed vessels, sample volume shape and acoustic ...

OBJECTIVE: Vascular malformations are uncommon but may confer significant morbidity. Limitations in diagnosis and treatment result from inadequate classification schema and diagnostic algorithms. The crucial distinction is between high-flow and low-flow lesions because this informs prognosis and treatment. This study assessed the utility of dynamic contrast-enhanced magnetic resonance imaging (dceMRI) ...

The effects of oxygen availability on neurovascular coupling were investigated using simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), in addition to the monitoring of physiological parameters, in 16 α-chloralose-anesthetized rats. Mild hypoxic hypoxia (oxygen saturation=83.6±12.1%) induced significant reductions in fMRI responses (P<0.05) to electrical stimulation in the forepaw, ...

Evaluation of cortical reorganization in chronic stroke patients requires methods to accurately localize regions of neuronal activity. Blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is frequently employed; however, BOLD contrast depends on specific coupling relationships between the cerebral metabolic rate of oxygen (CMRO(2)), cerebral blood flow (CBF), and ...

BACKGROUND: Obstetric hemorrhages are a frequent cause of maternal death all over the world, but are not routinely monitored. Health systems administrative databases could be used for this purpose, but data quality needs to be assessed. OBJECTIVES: Using blood transfusion data recorded in administrative databases to estimate the frequency of ...

OBJECTIVES: Our current knowledge of the physiological dilatation of spiral arteries in pregnancy, is based on histology. Real-time ultrasound visualisation of these changes may aid understanding of abnormal placentation. This study aimed to investigate if changes in the spiral artery blood flow can be followed 'in vivo' and explore the novel ...

BACKGROUND: Controversy exists regarding the optimal perfusion modality during cardiopulmonary bypass (CPB). Here we compare the effects of pulsatile versus nonpulsatile perfusion on microvascular blood flow during and after CPB. METHODS: High-risk cardiac surgical patients were randomly assigned to have pulsatile (n = 10) or nonpulsatile (n = 10) flow ...

INTRODUCTION: The complete blood count (CBC) with differential leukocyte count (DIFF) is an important part of clinical laboratory analyses and provides crucial data for clinicians. Delivery time after blood collection and conditions of storage is known to affect the reliability of results of some hematologic parameters. The aim of this ...

Perinetti G, Di Leonardo B, Di Lenarda R, Contardo L. Repeatability of gingival crevicular fluid collection and quantification, as determined through its alkaline phosphatase activity: implications for diagnostic use. J Periodont Res 2012.doi: 10.1111/j.1600-0765.2012.01508.x. © 2012 John Wiley & Sons A/S Background and Objective:  In spite of four decades of ...

Transfusion transmitted malaria (TTM) in non-endemic countries is reduced by questioning blood donors and screening of donated blood. Conventional screening is performed by Indirect Fluorescence Antibody Test (IFAT). This method is manual and difficult to standardize. Here we study the diagnostic performance of a multiplex assay for detection of antibodies ...

Elevated blood viscosity is an integral component of vascular shear stress that contributes to the site specificity of atherogenesis, rapid growth of atherosclerotic lesions, and increases their propensity to rupture. Ex vivo measurements of whole blood viscosity (WBV) is a predictor of cardiovascular events in apparently healthy individuals and studies ...

The study compared the effects of three blood concentration techniques after cardiopulmonary bypass on clinical hemostatic and ex-vivo rheological parameters. Residual blood of patients undergoing elective cardiac surgery was processed by centrifugation, cell salvage or ultrafiltration, and retransfused (n = 17 per group). Study parameters included blood loss, (free) hemoglobin, hematocrit, fibrinogen ...

In this study, a Pseudo three-dimensional Vision-based Nail-fold Morphological and Hemodynamic Analysis (PTVNMHA) is proposed to automatically extract morphological/hemodynamic features from a microscopic nail-fold image sequence, reconstruct the corresponding pseudo three-dimensional microvascular models, and visualize the dynamic blood flow in the model constructed. The morphological features extracted include the number, ...

Background: Medullary blood flow is via vasa recta capillaries, which possess contractile pericytes. In vitro studies using isolated descending vasa recta show that pericytes can constrict/dilate descending vasa recta when vasoactive substances are present. We describe a live kidney slice model in which pericyte-mediated vasa recta constriction/dilation can be visualized ...

Little information is available regarding the influence of non-ionic low-osmolar iodinated contrast medium (CM) in stored blood on the quality of blood components. We sought to evaluate the quality of such CM-contaminated blood in terms of the degree of hemolysis, production of microaggregates, level of iodine concentration, and RBC shape, ...

The micro-particle tracking velocimetry (μ-PTV) technique is used to obtain the velocity fields of blood flow in the microvasculature under in vivo conditions because it can provide the blood velocity distribution in microvessels with high spatial resolution. The in vivo μ-PTV technique usually requires a few to tens of seconds ...