Search results for "Blood"

Evaluation of regional haemodynamics and alterations of vascular wall of the lower limbs in hypertensive subjects

1995

This study was designed to analyse the relationship between arterial hypertension and changes in arterial blood flow and vascular wall damage of the lower limbs in hypertensive patients with various degrees of hypertension. Six hundred and fifty-four hypertensive patients (421 males and 233 females) aged 35 to 70 years and 88 healthy subjects (63 males and 25 females) aged 39 to 60 years were studied. Strain-gauge plethysmography of the lower limbs was used to calculate arterial calf blood flow (RF), arterial calf blood flow after post-ischaemic hyperaemia (PF), basal and minimal vascular resistances (BVR and MVR), time to reach peak flow (tPF), time until 50% reduction of peak flow (tT1/2)…

'Prefrontal' cognitive performance of healthy subjects positively correlates with cerebral FDOPA influx: an exploratory [18F]-fluoro-L-DOPA-PET inves…

2006

Dopamine neurotransmission influences those cognitive processes, which are generally regarded as prefrontal cortical functions. In previous positron‐emission‐tomography (PET) studies, net blood‐brain clearance of [(18)F]‐fluoro‐l‐DOPA (FDOPA) correlated with impaired cognitive performance in patients with Parkinson's disease or schizophrenia. We hypothesized that FDOPA influx also correlates with performance of cognitive tasks associated with prefrontal functioning in healthy volunteers. The net blood‐brain clearance of FDOPA (K [Formula: see text]) was mapped in a group of 11 healthy volunteers and calculated in striatal volumes‐of‐interest. The Wisconsin‐Card‐Sorting‐Test (WCST), Stroop‐T…

Brain activity during intra- and cross-modal priming: new empirical data and review of the literature

2003

A positron emission tomography (PET) study was conducted to investigate the neurofunctional correlate of auditory within-modality and auditory-to-visual cross-modality stem completion priming. Compared to the auditory-to-auditory priming condition, cross-modality priming was associated with a significantly larger regional cerebral blood flow (rCBF) decrease at the boundary between left inferior temporal and fusiform gyri, brain regions previously associated with modality independent lexical retrieval and reading. Instead, within-modality auditory priming was associated with a bilateral pattern of prefrontal rCBF increase. This was likely the expression of more efficient access to output lex…

Within-Day Energy Deficiency and Metabolic Perturbation in Male Endurance Athletes.

2018

Endurance athletes are at increased risk of relative energy deficiency associated with metabolic perturbation and impaired health. We aimed to estimate and compare within-day energy balance in male athletes with suppressed and normal resting metabolic rate (RMR) and explore whether within-day energy deficiency is associated with endocrine markers of energy deficiency. A total of 31 male cyclists, triathletes, and long-distance runners recruited from regional competitive sports clubs were included. The protocol comprised measurements of RMR by ventilated hood and energy intake and energy expenditure to predict RMRratio (measured RMR/predicted RMR), energy availability, 24-hr energy balance a…

A New Clinical and Immunovirological Score for Predicting the Risk of Late Severe Infection in Solid Organ Transplant Recipients: The CLIV Score

2020

Abstract Background We aimed at constructing a composite score based on Epstein-Barr virus DNAemia (EBVd) and simple clinical and immunological parameters to predict late severe infection (LI) beyond month 6 in solid organ transplantation (SOT) recipients. Methods Kidney and liver transplant recipients between May 2014 and August 2016 at 4 participating centers were included. Serum immunoglobulins and complement factors, peripheral blood lymphocyte subpopulations, and whole blood EBVd were determined at months 1, 3, and 6. Cox regression analyses were performed to generate a weighted score for the prediction of LI. Results Overall, 309 SOT recipients were followed-up for a median of 1000 da…

Red cell enzyme polymorphisms in Bulgaria.

1972

7 human red cell enzyme polymophisms have been typed on a sample of n=138 unrelated adults from Bulgaria, which revealed the following gene frequencies: ADA1=0.8623. ADA2=0.1376; AK1=0.9637, AK2=0.0362; 6-PGDA=0.9891, 6-PGDC=0.0108; PGM11=0.8346, PGM12=0.1653; PA=0.1596, PB=0.7983, PC=0.0420. In the LDH-system one B-subunit variant was found, whilst no Peptidase A or B variant could be observed. The anthropological significance of these findings is discussed.

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

1968

Prolonged preterm rupture of fetal membranes, a consequence of an increased maternal anti-fetal T cell responsiveness.

2005

A fetus, although semi-allogeneic, is usually accepted by the maternal immune system. However, complications, including alloresponsive mechanisms, are thought to be potentially detrimental for a successful pregnancy. Therefore, we compared allogeneic T cell responses of nonpregnant women with the response of healthy pregnant women and pregnant women who have various gestation-associated diseases. Peripheral blood mononuclear cells (PBMCs) of all three groups were stimulated with PBMCs from unrelated volunteers. Pregnant women had significantly reduced stimulation indices (SIs) compared with nonpregnant women. Exposing PBMCs from pregnant women to PBMCs of their own fetus led to a further si…

Automatic algorithm for monitoring systolic pressure variation and difference in pulse pressure.

2009

BACKGROUND: Difference in pulse pressure (dPP) reliably predicts fluid responsiveness in patients. We have developed a respiratory variation (RV) monitoring device (RV monitor), which continuously records both airway pressure and arterial blood pressure (ABP). We compared the RV monitor measurements with manual dPP measurements. METHODS: ABP and airway pressure (PAW) from 24 patients were recorded. Data were fed to the RV monitor to calculate dPP and systolic pressure variation in two different ways: (a) considering both ABP and PAW (RV algorithm) and (b) ABP only (RV(slim) algorithm). Additionally, ABP and PAW were recorded intraoperatively in 10-min intervals for later calculation of dPP …

Causal transfer function analysis to describe closed loop interactions between cardiovascular and cardiorespiratory variability signals

2004

Although the concept of transfer function is intrinsically related to an input-output relationship, the traditional and widely used estimation method merges both feedback and feedforward interactions between the two analyzed signals. This limitation may endanger the reliability of transfer function analysis in biological systems characterized by closed loop interactions. In this study, a method for estimating the transfer function between closed loop interacting signals was proposed and validated in the field of cardiovascular and cardiorespiratory variability. The two analyzed signals x and y were described by a bivariate autoregressive model, and the causal transfer function from x to y w…