Epicardial coronary arteries are called conductance arteries(1) (or "macrocirculation") as their normal intrinsic resistance is close to zero(2) and their main function is to transport blood. They are visible at invasive coronary angiography with an unsurpassed spatial and temporal resolution. Coronary arteries smaller than 500 µm are usually referred to ...

The impacts of large dams on the hydrology and ecology of river systems are well understood, yet the impacts of low-head structures are poorly known. While impacts of small weirs on upstream-migrating fish have long been mitigated by fish ladders, it is assumed that downstream migration of surface-oriented fishes is ...

BACKGROUND: Recent advances in echocardiography have allowed assessment of flow velocity in the epicardial coronary arteries of patients with ischemic heart disease, using transthoracic color Doppler echocardiography (TTDE). However, few data are available regarding coronary blood flow in patients with hypertrophic cardiomyopathy (HCM). OBJECTIVE: To assess the epicardial coronary arteries ...

BACKGROUND: Diagnosis of coronary disease and microvascular dysfunction may be improved by comparing myocardial perfusion scans with a database defining the lower limit of normal myocardial blood flow and flow reserve (MFR). To maximize disease detection sensitivity, a small normal range is desirable. Both (13)N-ammonia and (82)Rb tracers are used ...

The recovery of myocardial blood flow is a major indicator of the effectiveness of cell-based therapies for ischemic heart diseases including myocardial infarction. Blood flow (also called perfusion) of the heart muscle can be noninvasively measured via imaging methods such as ultrasound, positron emission tomography (PET), or magnetic resonance imaging ...

The expected blood flow improvement following a coronary intervention is inversely related to the stenotic-to-normal flow ratio Qs/Qn. Since Qn cannot be measured prior to intervention, treatment decisions rely on stenosis-severity indices, e.g., area stenosis (%AS), hyperemic stenosis resistance (HSR), and fractional flow reserve (FFR), where treatment cut-off levels have ...

In order for habitat restoration in regulated rivers to be effective at large scales, broadly applicable frameworks are needed that provide measurable objectives and contexts for management. The Ecological Limits of Hydrologic Alteration (ELOHA) framework was created as a template to assess hydrologic alterations, develop relationships between altered streamflow and ...

We report on a numerical study wherein we modeled the influence of the segmentation ring used in the recently introduced parallel segmented flow concept. The study reconfirms that the parallel segmented flow concept can indeed improve separation performance of radially heterogeneous beds. It was however also found that the segmentation ...

Background: We investigated in a porcine model whether measuring both the flow distal to an anastomosis and the graft transit time flow (TTF) gives a more accurate picture of the true blood flow in the left anterior descending artery (LAD) than graft TTF measurement alone.Methods: We performed off-pump coronary artery ...

A rapid and eco-friendly synthesis of a sulfonamide library under flow conditions is described. The study illustrates an efficient, safe and easily scalable preparation of sulfonamides by use of a mesoreactor apparatus, thus demonstrating the impact of flow technologies within drug discovery. Waste minimization, employment of green media and non ...

Rationale: The spatial distribution of blood flow in hearts of genetically modified mice is a phenotype of interest as derangements in blood flow may precede detectable changes in organ function. However, quantifying the regional distribution of blood flow within organs of mice is challenging because of the small organ volume ...

We present the results of a computational study of the entire left coronary system simulated both at Newtonian level and at red blood cell resolution for a sizeable number of physiological conditions. We analyze the cardiovascular implications of stenotic plaques and show that the standard clinical criterion for surgical or ...

Routine quantification of myocardial blood flow (MBF) requires robust and reproducible processing of dynamic image series. The goal of this study was to evaluate the reproducibility of 3 highly automated software programs commonly used for absolute MBF and flow reserve (stress/rest MBF) assessment with 82Rb PET imaging. METHODS: Dynamic rest ...

In this study, the flow characteristics through specific concentric and eccentric plaque formations are investigated via Large Eddy Simulation (LES) turbulence technique considering pulsatile flow conditions adjusted for a single frequency-sinusoidal motion (SIN) and for the coronary arteries namely the Left Anterior Descending (LAD) and Right Coronary Artery (RCA). This ...

BACKGROUND: Although extremely high blood thrombogenicity has been reported in patients with acute myocardial infarction, it has not been clarified if the increased blood thrombogenicity is a cause of acute myocardial infarction or a mere result induced by thrombus formation at the disrupted plaque. Therefore, we examined if blood thrombogenicity ...

We aimed to assess the utility of HitAlert flow cytometry as a diagnostic functional heparin-induced thrombocytopenia (HIT) assay in a tertiary care hospital. The 4Ts score was used to assess pretest probability of HIT in 37 patients. Serum was analysed for HIT antibodies by the flow cytometry HitAlert assay. Results ...

ABSTRACT: Selepressin is a new selective vasopressin V1a agonist for treatment of vasodilatory hypotension in shock. Its effect on coronary and aortic blood flow, hemodynamics, and electrocardiogram as an indication of drug safety in healthy dogs were compared with arginine vasopressin (AVP). Eight dogs were fasted, anesthetized, intubated, and ventilated. ...

Context :  Injury management commonly includes decreasing arterial blood flow to the affected site in an attempt to reduce microvascular blood flow and edema and limit the induction of inflammation. Applied separately, ice and menthol gel decrease arterial blood flow, but the combined effects of ice and menthol gel on ...

We present findings in a 17-year-old with interrupted aortic arch, in whom standard imaging techniques missed functional and morphological problems. Flow-sensitive four-dimensional magnetic resonance (4-D MR) enabled assessment of the complex anatomy and blood-flow characteristics in the entire aorta and direct quantification of blood flow in collateral vessels. Our findings ...

It has been shown that the echogenicity of blood varies during a flow cycle under pulsatile flow both in vitro and in vivo. In general, the echogenicity of flowing whole blood increases during the early systole phase and then reduces to a minimum at late diastole. While it has been postulated that ...

"This is the first example of highly stereo- and chemoselective enamine catalysis in a continuous flow reactor on a scale of >100 g (>450 mmol)." This and more about the story behind the front cover research can be found on p. 212.

Objective: Metabolic syndrome (MetS) is a strong predictor of cardiovascular events and coronary flow reserve (CFR), an indicator of microvascular function, has been found to be impaired in MetS. Aortic stiffness (AS) is a simple and effective method for assessing arterial elasticity. The aim of this study was to evaluate ...

OBJECTIVE: It has been recently shown that cardiac syndrome X (CSX) patients with slow coronary flow (SCF) have a worse long-term prognosis than those with normal coronary flow. Increased uric acid levels were shown to be associated with atherosclerosis, oxidative stress, and endothelial dysfunction. The purpose of the study was ...

Abstract Objective: To review the current literature addressing the visualisation and clinical applicability of coronary artery blood flow in various foetal and neonatal settings. Method: We reviewed original research papers, commentaries and review articles which studied the usefulness of coronary flow assessments in the growth restricted foetus, healthy neonates and ...

PURPOSE: The aim of the study was to determine whether glucose uptake in viable myocardium of ischemic cardiomyopathy patients depends on rest myocardial blood flow (MBF) and the residual myocardial flow reserve (MFR). METHODS: Thirty-six patients with ischemic cardiomyopathy (left ventricular ejection fraction 25 ± 10 %) were studied with (13)N-ammonia and (18)F-fluorodeoxyglucose ...

Flow cytometry allows the assessment of multiple sperm parameters following a diverse number of protocols. Here, we describe three methods for evaluating critical aspects of sperm quality: the double stain SYBR-14 and propidium iodide (PI) for assessing sperm viability; the double stain PNA-FITC (peanut agglutinin-fluorescein isothiocyanate) and PI for assessing ...

Our objective is to test the hypothesis that coronary endothelial function (CorEndoFx) does not change with repeated isometric handgrip (IHG) stress in CAD patients or healthy subjects. Coronary responses to endothelial-dependent stressors are important measures of vascular risk that can change in response to environmental stimuli or pharmacologic interventions. The ...

Tortuous coronary arteries are commonly observed in clinical screenings and it may cause a reduction of the coronary pressure. However, whether this reduction leads to significant decreasing in the coronary blood supply is still unknown. The purpose of this study was to investigate the effect of the coronary tortuosity (CT) ...

BACKGROUND: Episodes of microvascular proliferation associated with volume expansion have been observed in arteriovenous malformations (AVMs) of skin and soft tissue. OBJECTIVE: We sought to investigate the relationship between a microvascular proliferative response and flow velocity in AVMs. METHODS: Resection specimens of 80 AVMs were clinically categorized as either high- ...

The 12th International Conference on Flow Analysis, referred to as 'Flow Analysis XII' was a 5-day scientific meeting that covered all recent advances in the field of flow analytical techniques. The most interesting presentations pertaining to bioanalytical work are summarized in this report.

Fractional flow reserve is a vital tool for assessing the functional significance of a coronary stenosis, with higher sensitivity and specificity relative to non-invasive techniques. This article reviews the basic principles and applications of fractional flow reserve measurement, potential pitfalls and areas of controversy.

Acute coronary syndromes (ACS) still represent a major cause of death in Western countries; in the vast majority of cases, coronary atherosclerosis represents the common pathological lesion to all forms of ACS. It is currently believed that plaque complication (rupture, fissuration, and so on), with the consequent superimposed thrombosis, is ...

OBJECTIVES: Intracoronary shunts have been developed for a bloodless field and preserved forward flow preventing ischemia during off-pump coronary artery bypass (OPCAB) surgery. However, reports directly measuring the forward flow through the shunt in clinical settings are lacking. METHODS: Using a 7.5-MHz Doppler probe, we investigated the coronary flow through ...

The Opuha Dam was designed for water storage, hydropower, and to augment summer low flows. Following its commissioning in 1999, algal blooms (dominated first by Phormidium and later Didymosphenia geminata) downstream of the dam were attributed to the reduced frequency and magnitude of high-flow events. In this study, we used ...

OBJECTIVE: At present, the precise pathophysiology of the slow coronary flow phenomenon (SCFP) is still unknown and there is no consensus as to how it should be treated. The rheological factors affect the clinical course of various cardiovascular diseases. We studied the intrinsic properties of blood in the SCFP. MATERIALS ...

BackgroundHeterogeneity of arterial transit time due to cerebral artery steno-occlusive lesions hampers accurate regional cerebral blood flow measurement by arterial spin labeling (ASL).PurposeTo assess the feasibility of regional cerebral blood flow measurement by ASL with multiple-delay time sampling in patients with steno-occlusive diseases by comparing with positron emission tomography (PET), ...

AIM: To determine whether contrast-enhanced computed tomography (CT) performed with a high flow rate and short delay protocol or a lower flow rate and longer delay protocol resulted in better enhancement of the oral cavity and oropharyngeal tumour and tumour edge delineation. MATERIALS AND METHODS: Patients with squamous cell carcinomas ...

We study a reversal process in Stokes flows in the presence of weak diffusion in order to clarify the distinct effects that chaotic flows have on the loss of reversibility relative to nonchaotic flows. In all linear flows, including a representation of the baker's map, we show that the decay ...

Background: Hypercholesterolemia induces early microcirculatory functional and structural alterations that are reversible by cholesterol reduction. Real time myocardial contrast echocardiography (RTMCE) and vascular ultrasound evaluate the effects of hyperlipidemia on peripheral and central blood flow reserve. This study investigated the effects of lipid-lowering therapy on coronary and peripheral artery circulation ...

In medical practice, bypass grafts are commonly used as an alternative route around strongly stenosed or occluded arteries. In contrast to arterial bifurcations, surgically created anastomosis can be modified with the objective of enabling optimal graft geometry to yield a flow environment that improves its longevity. This paper presents a ...

Vein of Galen malformation (VGAM) in neonates presents a complex management challenge. Measurement of superior vena cava (SVC) blood flow may provide insights into the haemodynamics of VGAM and the effects of therapeutic intervention. SVC flow was assessed in 15 neonates with VGAM. SVC flow results, Bicêtre scores (clinical assessment), ...

A high-grade stenosis to viable myocardium typically produces a positive fractional flow reserve. In the present report, a case of subtotal occlusion of a saphenous vein graft to a viable myocardial territory with normal fractional flow reserve is described, and a possible explanation for this observation is discussed.

There is an increased body of evidence to suggest that the vasa vasorum play a major role in the progression and complications of vulnerable plaque leading to acute coronary syndrome. We propose that detecting changes in the flow in the vascular wall by intravascular ultrasound signals can quantify the presence ...

Fractional flow reserve (FFR) is an important prognostic determinant in a clinical setting. However, its measurement currently requires the use of invasive pressure wire, while an angiographic technique based on first-pass distribution analysis and scaling laws can be used to measure FFR using only image data. Eight anesthetized swine were ...

Background. The significance of flow cytometry indicating myelodysplasia without proof of myelodysplasia by cytomorphology remains to be clarified. Design and Methods. In 142 patients analyzed in parallel by flow cytometry, cytomorphology and cytogenetics for suspected myelodysplasia without proof of myelodysplasia by cytomorphology we evaluated follow-up analyses. Results. At initial assessment ...

Objective. To investigate the effect of delayed cord clamping (DCC), compared to early cord clamping (ECC) on maternal postpartum hemorrhage (PPH) and umbilical cord blood gas sampling. Design. Secondary analysis of a parallel-group, single center, randomized controlled trial. Setting. Swedish county hospital. Population. A total of 382 term deliveries after ...

It is generally considered that the genesis of myelopathy associated with the degenerative conditions of the spine may result from both mechanical compression and circulatory disturbance. Many references about spinal cord tissue ischemic damage can be found in the literature, but not detailed studies about spinal cord microvasculature damage related ...

In Expériences sur le principe de la vie (Chez D'Hautel, Paris, 1812), Jean César Legallois, a French physician and physiologist, explored the basic regulatory framework of vital processes of warm-blooded animals. He decapitated rabbits and cut off their limbs in order to search for a seat of life that is ...

Cord leptin is a biomarker of fetal growth and adiposity with a role in predicting weight gain during the first months of life and childhood obesity. Our objective was to calculate gender-specific reference intervals for cord blood leptin in healthy neonates in Crete, Greece. We used data from the prospective ...

INTRODUCTION: An umbilical cord blood bank was recently opened in our institution as an alternative source of hematopoietic stem cells. Before inclusion of a cord blood in an international register, a WBC with differential is requested, among others. Currently, the reference method is the microscopic manual count, and we sought ...