Regional control of blood flow is often suggested as a mechanism for fine thermoregulatory adjustments in snakes. However, the flow of blood to different body regions at various temperatures has never been visualized to confirm this mechanism. We used (99m)technetium-labelled macroaggregated albumin ((99m)Tc-MAA), a radioactive tracer, to follow the flow ...

Measurement of blood volume (BV) may guide fluid and red blood cell management in critically ill patients when capillary leak from shock and fluid resuscitation makes assessment of intravascular volume difficult. This is a prospective randomized trial of critically ill surgical patients with septic shock, severe sepsis, severe respiratory failure, ...

Recent experimental and imaging studies suggest that the influence of gravity on the measured distribution of blood flow in the lung is largely through deformation of the parenchymal tissue. To study the contribution of hydrostatic effects to regional perfusion in the presence of tissue deformation, we have developed an anatomically ...

Recent evidence in the literature suggests that tissues play a greater role than blood in reducing nitrite to NO under ischemic or hypoxic conditions. Our previous mathematical model for coupled NO and O(2) transport around an arteriole, modified to include superoxide generation from dysfunctional endothelium, was developed further to include ...

A variety of polymer nanoparticles (NP) are under development for imaging and therapeutic use. However, little is known about their behavior. This study examined pharmacokinetics, distribution and elimination of stable polyacrylamide (PAA) nanoparticles (~31 nm average diameter). PAA NPs and polyethylene glycol-coated PAA NPs were injected into the tail veins ...

Migraine is associated with an increased risk of deep white matter lesions and subclinical posterior circulation infarcts. A significant association between deep white matter hyperintensities and cerebral atrophy is true for various neurological diseases; it was not specifically proven in migraine. The aim of this study was to evaluate the ...

Introduction: Intradialytic hypotension remains the most common complication for outpatient hemodialysis, and relative blood volume monitoring was designed to reduce hypotension. Reports of the usefulness of this technology, however, have been variable. Methods: We audited the usefulness of relative blood volume monitoring recorded throughout the mid-week dialysis in 72 stable ...

This study investigated the hemodynamic properties of the plantar venous plexus (PVP), a peripheral venous pump in the human foot, with Doppler ultrasound. We investigated how different ways of introducing mechanical changes vary in effectiveness of displacing blood volume from the PVP. The contribution of the PVP was analyzed during ...

To compare cardiac output (CO) and blood volumes measured by COstatus(®) (Transonic Systems Inc., NY, USA) versus PiCCO (Philips IntelliVue MP40 with PiCCO-technology module M3012A#10, Netherlands) in adult ICU patients. This was a prospective single-center study. Each of the 30 patients studied received a 5-Fr Pulsiocath femoral arterial and a ...

Electrical stimulation of calf muscles has been shown to be effective in prevention of DVT. The aim was to determine: (a) dependence of venous blood velocity and ejected volume on the rates of stimulated calf contractions: (b) clinical factors affecting efficacy in healthy individuals. The maximum intensity stimulus tolerated was ...

(11)C-ABP-688 is a selective tracer for the mGluR5 receptor. Its kinetics is fast and thus favourable for an equilibrium approach to determine receptor-related parameters. The purpose of this study was to test the hypothesis that the pattern of the (11)C-ABP688 uptake using a bolus-plus-infusion (B/I) protocol at early time points ...

BACKGROUND: Needlestick injuries are always associated with a risk of infection, because these types of punctures may expose healthcare workers to a patient's blood and/or body fluids. OBJECTIVE: To compare the efficacy of 4 different types of surgical gloves for preventing exposure to blood as a result of needlestick injury. ...

AIM: To determine the perifollicular vascular network and blood flow changes of the dominant preovulatory follicle using quantitative three-dimensional (3D) power Doppler analysis. METHODS: A total of 21 cycles were studied in spontaneously ovulating women who underwent folliculometry and 3D power Doppler angiography of perifollicular blood flow of the dominant ...

This study was designed to determine if acute distension of the hindlimb venous circulation stimulates breathing, thereby contributing to the respiratory responses to rapid changes in total blood volume. In 10 spontaneously breathing anesthetized sheep, we withdrew 15 ml kg(-1) of blood from a femoral vein over approximately 1-2 min. ...

To investigate blood flow alterations and their determinants after free flap transfer, we focused on a vascularized latissimus dorsi muscle segment for reconstruction of the paralyzed face as an ideal model, since the vascular pedicle and type of flap are identical among patients. Seventeen patients were studied using color Doppler ...

BACKGROUND: Assessment of the radial pulse by palpation (pulse diagnosis) is an important diagnostic technique in Traditional Chinese Medicine (TCM), but the changes of blood flow volume in the radial artery during and after acupuncture are unknown. OBJECTIVE: The aim of this study was to explore the changes of radial ...

Blood-injection-injury (BII) phobia patients sometimes faint during exposure to relevant stimuli. However, mechanisms and timing of physiological adjustments in BII phobia remain poorly understood. In a larger sample of 60 patients and 20 controls, we sought to replicate findings of a prior study demonstrating the role of hyperventilation in the ...

We report the first measurement of the hindrance function for sedimentation or creaming of disk-shaped colloids via the analytical centrifugation. Disks align with the external flow right above a volume fraction of a few percent, and this effect is extremely sensitive to the aspect ratio of disks. Due to this ...

The Frank-Starling mechanism describes the relationship between stroke volume and preload to the heart, or the volume of blood that is available to the heart--the central blood volume. Understanding the role of the central blood volume for cardiovascular control has been complicated by the fact that a given central blood ...

Stroke volume is mainly determined by preload, afterload and contractility. Accordingly, measuring cardiac preload provides essential information for treatment of hemodynamically unstable patients. Hemodynamic monitoring is widely used to measure cardiac preload, but the monitoring method is time-consuming and invasive. It is therefore important to establish a simple and non-invasive ...

The paper presents the investigations on first flush phenomenon based on the total suspended solids (TSS) concentration measurement during selected rainfalls at central part of Czestochowa (Poland) and also the hydrodynamic model of the catchment. The model allows to present the conception of first flush management using an improved flow ...

A crucial point in the haemodialysis (HD) treatment is the reliable assessment of hydration status. An inadequate removed volume may lead to chronic fluid overload which can lead to hypertension, left ventricular hypertrophy and heart failure. Therefore, the estimation of the hydration state and the management of a well-tolerated water ...

The definition and clinical significance of vertebral artery hypoplasia (VAH) remain inconclusive. VAH has been proposed as a predisposing factor of posterior circulation ischemic stroke. The aim of this study was to determine a best cut-off diameter of vertebral artery (VA) for VAH and to investigate if unilateral VAH is ...

In traditional Japanese and Chinese medicine, warming the abdomen with moxibustion or herbal medicines has been used for various diseases. However, the effects of these therapies on hemodynamics have not been clear. We clarify the physiological effects of these therapies on the superior mesenteric artery (SMA) blood flow. 28 healthy ...

BACKGROUND: The beating heart is the generator of blood flow through the cardiovascular system. Within the heart's own chambers, normal complex blood flow patterns can be disturbed by diseases. Methods for the quantification of intra-cardiac blood flow, with its 4D (3D+time) nature, are lacking. We sought to develop and validate ...

We investigate the effects of blood flow and extravascular tissue shearing on diffusing-wave spectroscopy (DWS) signals from deep tissue, using an ex vivo porcine kidney model perfused artificially at controlled arterial pressure and flow. Temporal autocorrelation functions g((1))(τ) of the multiply scattered light field show a decay which is described ...

To evaluate whether the volume of blood suctioned during vacuum-assisted breast biopsy (VABB) is associated with hematoma formation and progression, patient's age and histology of the lesion. 177 women underwent VABB according to standardized protocol. The volume of blood suctioned and hematoma formation were noted at the end of the ...

The performance of down-flow hanging sponge (DHS) system treating UASB reactor effluent at different sponge volume of 38.2, 28.7, 19.1 and 9.6% was investigated. The hydraulic retention time (HRT) and flow rate were kept constant at 2.6 h and 0.46 m(3)/day, respectively. The results obtained indicated that reducing the sponge ...

Daikenchuto is a traditional herbal medicine that is used for the treatment of cold feeling in the abdomen, while Orengedokuto, also a traditional herbal medicine, is used for treating inflammatory and ulcerative diseases affecting internal organs. However, the effects of these herbal medicines on cardiac output (CO) and intestinal blood ...

BACKGROUND: An element lacking in medical education is training to estimate blood volumes. Therefore, health care workers currently use visual estimation as their only means of determining blood volumes, which has shown to be highly inaccurate. This study proposes and tests a new method using one's fist to determine external ...

Fish typically use a rostro-caudal wave of head expansion to generate suction, which is assumed to cause a uni-directional, anterior-to-posterior flow of water in the expanding head. However, compared with typical fish, syngnathid fishes have a remarkably different morphology (elongated snout, small hyoid, immobile pectoral girdle) and feeding strategy (pivot ...

Head-up tilt (HUT) redistributes approximately 700 mL of blood to the dependent regions. In a gravitational field, hydrostatic pressure is balanced against vascular compliance, resulting in a hydrostatic indifferent point (HIP) whose location should be coincident with an indifferent point for volume (VIP). Cardiac filling is determined by the hydrostatic ...

Sepsis has been reported to increase the volume of distribution of gentamicin in neonates. To determine whether this was caused by the use of intravenous volume expanders a retrospective nested case-control study was performed comparing confirmed septic neonates with non-septic controls. Data were collected on intravenous administration of 0.45% saline/10% ...

The altitude performance of two NO analysers using different NO detectors was studied. The analysers and their flow regulators were tested with simulated exhalations of reference gases. At 4000 m, volume flow was +35% and mass flow -24% of nominal in both instruments. The reduced mass flow increased the exhaled ...

BACKGROUND: After the introduction of sidestream darkfield imaging (SDF) of the microcirculation, it has become clear that in sepsis, microcirculatory alterations can exist in the absence of systemic haemodynamic abnormalities. However, it is unclear whether this phenomenon also occurs in the treatment of end-stage kidney disease (ESKD) where alterations in ...

BACKGROUND: Large convective volumes are recommended for online haemodiafiltration (HDF) to maximize solute removal. There has been little systematic evaluation of factors that determine convective volumes in routine clinical practice. METHODS: In the present study, potential patient- and treatment-related determinants of convective volume were analysed in 235 consecutive patients on ...

Analysis of gene expression is often used to evaluate the effects of experimental manipulations in laboratory animals. Blood is a rich source of potential biomarkers, including gene expression information, which may be obtained from whole blood. When compared with the end of a study, when whole blood samples can be ...

Advanced haemodynamic monitoring via transpulmonary thermodilution (TPTD) devices has gained popularity in recent years. The intrathoracic blood volume index (ITBVI) and the global end-diastolic blood volume index (GEDVI) calculated by single indicator TPTD devices have been shown to reliably estimate cardiac preload. The normal range of values for ITBVI is ...

OBJECTIVE: To remodel and validate commercially available monitors and their Pitot tube-based flow sensors for use in large animals, using in vitro techniques. STUDY DESIGN: Prospective, in vitro experiment. METHODS: Both the original and the remodelled sensor were studied with a reference flow generator. Measurements were taken of the static ...

In children, the prescribed ultrafiltration needed to achieve the fixed end session dry weight can induce hypotensive episodes. A variety of on-line devices based on the direct measurement of the hematocrit are available, but these devices nearly always only measure the quantitative variation in the blood volume as the means ...

The development of valid methods for repeatedly measuring red blood cell (RBC) volume (RCV) in the same individual would be useful in furthering understanding of the physiology and pathophysiology of the pregnant woman, fetus, and infant under a variety of conditions. Small volumes (5 to 100 mL) of either sheep ...

BACKGROUND: This study evaluated whether commercially available blood volume measurements in critically ill surgical patients altered fluid management. METHODS: Patients admitted to the surgical intensive care unit of a tertiary care teaching hospital were prospectively evaluated. The frequency of changes in fluid management when results of blood volume measurements were ...

BACKGROUND: The immediate effect of acute haemorrhage is a significant reduction in tissue blood flow, frequently resulting in haemorrhagic shock. The main aim of resuscitation after bleeding is the immediate restoration of intravascular volume. Intravenous administration of volume expanders should be commenced immediately, regardless of whether they are colloids or ...

BACKGROUND AIMS: Volume reduction is the usual process in cord blood banking that has some advantages regarding reducing the storage space and dimethyl sulfoxide (DMSO) quantity in the final product. The volume reduction methodology must guarantee high cell recovery and red blood cell (RBC) depletion by reducing all the umbilical ...

BACKGROUND: Conventional concept suggests that infused crystalloid fluid is first distributed in the plasma volume and then, since the capillary permeability for fluid is very high, almost instantly equilibrates with the extracellular fluid space. We challenge whether this view is consistent with findings based on volume kinetic analysis. METHODS: Fifteen ...

Molecular electronics and nanoscale chemical sensors could enable the construction of microscopic sensors capable of detecting patterns of chemicals as they flow passively in a fluid. Information from a large number of such devices allow the estimation of properties of tiny chemical sources in a macroscopic tissue volume. Although such ...

OBJECTIVE: Needlestick injuries are the most common injuries that occur among operation room personnel in the health care service. The risk of infection after a needlestick injury during surgery greatly depends on the quantity of pathogenic germs transferred at the point of injury. The aim of this study was to ...

OBJECTIVE: Fetal alloimmune anemia is associated with increased blood flow velocities and cardiomegaly. In severe cases, hydrops can develop. We investigated whether the decrease of red blood cell volume is associated with a reduction or expansion of plasma volume. METHODS: In 86 alloimmunized fetuses that received a first intrauterine transfusion, ...

Vascular volume is of fundamental significance to the function of the cardiovascular system. An accurate prediction of blood volume in patients is physiologically and clinically significant. This study proposes what we believe is a novel volume scaling relation of the form: V(c)=K(v)D(s)(2/3)L(c), where V(c) and L(c) are cumulative vessel volume ...

Blood in the splanchnic vasculature can be transferred to the extremities. We quantified such blood shifts in normal subjects by measuring trunk volume by optoelectronic plethysmography, simultaneously with changes in body volume by whole body plethysmography during contractions of the diaphragm and abdominal muscles. Trunk volume changes with blood shifts, ...