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Proteus syndrome (PS) is an exceptionally uncommon genetic disorder that has been documented in only approximately 250 cases in the literature spanning the past four decades. It is characterized by a disproportionate, asymmetric overgrowth of all types of tissues, provoked by a somatic activating mutation in serine/threonine protein kinase 1. We report a case of PS in a two-year-old female patient with the following clinical features: unilateral overgrowth of connective tissue in the right buttock and right foot, where multiple surgeries were performed to achieve a desirable aesthetic outcome and ensure psychological comfort of the young patient. The insights provided by this case underscore the pivotal role of obtaining pleasing aesthetic outcomes in the surgical management of untreatable genetic disorders, with the aim of nurturing psychological contentment in affected children.

Abstract Background This study explores the effectiveness of ultrasonography (USG)-guided saline enema reduction for ileocecal intussusception. It investigates factors, ascertainable through physical examination, ultrasound, and medical history, that impact the success of the procedure and the likelihood of recurrence. Results Conducted at a tertiary referral center, the study included 323 pediatric cases diagnosed with intussusception between 2017 and 2023. Patient data, symptoms, signs, and outcomes were collected. Hydrostatic saline enema, performed under USG guidance, served as the primary non-operative treatment. Logistic regression models assessed the impact of clinical factors on success and recurrence rates. Out of 323 patients examined for eligibility, 184 met inclusion criteria and were analyzed. Successful reduction with saline enema was achieved in 86.7%. In-hospital recurrence occurred in 17.1%, notably higher for intussusceptions extending into the rectum (p 24 (p = 0.4) and 48–72 (p = 0.2) hours did not decrease chances for successful reduction. Conclusions Prolonged symptom duration of over 24 and 48–72 h should not be a definitive contraindication for non-operative treatment. Cumulation of symptoms typical for intussusception might reduce the chances of success. These findings contribute valuable insights into optimizing non-operative strategies for managing pediatric intussusception.

Abstract We show that the interaction between ferromagnetic Fe(110) and antiferromagnetic CoO(111) sublayers can be mediated and precisely tuned by a nonmagnetic Au spacer. Our results prove that the thickness of the Fe and Au layers can be chosen to modify the effective anisotropy of the Fe layer and the strength of the exchange bias interaction between Fe and CoO sublayers. Well-defined and tailorable magnetic anisotropy of the ferromagnet above Néel temperature of the antiferromagnet is a determining factor that governs exchange bias and interfacial CoO spins orientation at low temperatures. In particular, depending on the room temperature magnetic state of Fe, the low-temperature exchange bias in a zero-field cooled system can be turned “off” or “on”. The other way around, we show that exchange bias can be the dominating magnetic anisotropy source for the ferromagnet and it is feasible to induce a 90-degree rotation of the easy axis as compared to the initial, exchange bias-free easy axis orientation.

A new type of silver nanoparticles (AgNPs) was prepared and comprehensively studied. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) analyses indicated that 24 nm AgNPs with narrow size distribution were obtained while Z-potential confirms their good stability. The composites of the obtained AgNPs with nontoxic-nature-inspired hydrogel were formed upon cooling of the aqueous solution AgNPs and C12Ala. The thermal gravimetric analysis (TGA) and the differential scanning calorimetry (DSC) do not show significant shifts in the characteristic temperature peaks for pure and silver-enriched gels, which indicates that AgNPs do not strongly interact with C12Ala fibers, which was also confirmed by SEM. Both AgNPs alone and in the assembly with the gelator C12Ala were almost biologically passive against bacteria, fungus, cancer, and nontumor human cells, as well as zebra-fish embryos. These studies proved that the new inactive AgNPs-doped hydrogels have potential for the application in therapy as drug delivery media.

Effective progenitor cell recruitment to the ischemic injury zone is a prerequisite for any potential therapeutic effect. Cell uptake determinants in humans with recent myocardial infarction are not defined. We tested the hypothesis that myocardial uptake of autologous CD34+ cells delivered via an intracoronary route after recent myocardial infarction is related to left ventricular (LV) ejection fraction (LVEF) and infarct size.Thirty-one subjects (age, 36-69 years; 28 men) with primary percutaneous coronary intervention-treated anterior ST-segment-elevation myocardial infarction and significant myocardial injury (median peak troponin I, 138 ng/mL [limits, 58-356 ng/mL]) and sustained LVEF depression at 45% were recruited. On day 10 (days 7-12), 4.3×106 (0.7-9.9×106) 99mTc-extametazime-labeled autologous bone marrow CD34+ cells (activity, 77 MBq [45.9-86.7 MBq]) were administered transcoronarily (left anterior descending coronary artery). 99mTc-methoxyisobutyl isonitrile (99mTc-MIBI) single-photon emission computed tomography before cell delivery showed 7 (2-11) (of 17) segments with definitely abnormal/absent perfusion. Late gadolinium-enhanced infarct core mass was 21.7 g (4.4-45.9 g), and infarct border zone mass was 29.8 g (3.9-60.2 g) (full-width at half-maximum, signal intensity thresholding algorithm). One hour after administration, 5.2% (1.7%-9.9%) of labeled cell activity localized in the myocardium (whole-body planar γ scan). Image fusion of labeled cell single-photon emission computed tomography with LV perfusion single-photon emission computed tomography or with cardiac magnetic resonance infarct imaging indicated cell uptake in the peri-infarct zone. Myocardial uptake of labeled cells activity correlated in particular with late gadolinium-enhanced infarct border zone mass (r=0.84, P<0.0001); it also correlated with peak TnI (r=0.76, P<0.001), severely-abnormal/absent perfusion segment number (r=0.45, P=0.008), and late gadolinium-enhanced infarct core (r=0.58, P=0.0003) but not with echocardiography LVEF (r=-0.07, P=0.68) or gated single-photon emission computed tomography LVEF (r=-0.28, P=0.16. The correlation with cardiac magnetic resonance imaging-LVEF was weak (r=-0.38; P=0.04).This largest human study with labeled bone marrow CD34+ cell transcoronary transplantation after recent ST-segment-elevation myocardial infarction found that myocardial cell uptake is determined by infarct size rather than LVEF and occurs preferentially in the peri-infarct zone. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to assess the prognostic value of right ventricular (RV) involvement diagnosed by cardiac magnetic resonance (CMR) early after ST-elevation myocardial infarction (STEMI). Background: CMR allows accurate and reproducible RV assessment. However, there is a paucity of data regarding the prognostic value of RV involvement detected by CMR early after STEMI. Methods: Ninety-nine patients (77 men, mean age 57 ± 11 years) who underwent CMR 3 to 5 days after STEMI treated with primary angioplasty were followed for 1,150 ± 337 days for cardiac events (cardiac death, nonfatal myocardial infarction [MI], and hospitalizations due to decompensated heart failure). Cox proportional hazards model was applied in stepwise forward fashion to identify outcome predictors. Event-free survival was estimated by Kaplan-Meier method and compared between groups by the log-rank test. Results: Cardiac events occurred in 34 patients (7 cardiac deaths, 8 MIs, 26 hospitalizations). By multivariable analysis, the independent outcome predictors were left ventricular (LV) MI transmurality index (hazard ratio: 1.03 per 1%; 95% confidence interval: 1.01 to 1.04; p = 0.001), RV ejection fraction (RVEF) (hazard ratio: 1.46 per 10% decrease; 95% confidence interval: 1.05 to 2.02; p = 0.03), and RVMI extent (hazard ratio: 1.50 per each infarcted RV segment; 95% confidence interval: 1.11 to 2.01; p = 0.007). Compared with clinical data (global chi-square = 5.2), LV ejection fraction [LVEF] (global chi-square = 11.1), RVEF (global chi-square = 17.1), LVMI transmural extent (global chi-square = 26.0), and RVMI extent (global chi-square = 34.9) improved outcome prediction in sequential Cox model analysis (p < 0.05 for all steps). RVEF stratified risk in patients with LVEF <40% in whom the 4-year event-free survival was 66.7% for RVEF ≥40% and 40.0% for RVEF <40% (p < 0.05). Conclusions: The extent of RVMI and RV dysfunction assessed early after STEMI are independent outcome predictors, which provide incremental prognostic value to clinical data, LV systolic function, and infarct burden. Measurement of RVEF may be particularly useful to stratify risk in patients with depressed LV function after STEMI. [Copyright &y& Elsevier]

Objectives: To compare a steady-state free precession cine sequence–based technique (feature tracking [FT]) to tagged harmonic phase (HARP) analysis for peak average circumferential myocardial strain (εcc) analysis in a large and heterogeneous population of boys with Duchenne muscular dystrophy (DMD). Background: Current εcc assessment techniques require cardiac magnetic resonance–tagged imaging sequences, and their analysis is complex. The FT method can readily be performed on standard cine (steady-state free precession) sequences. Methods: We compared mid-left ventricular whole-slice εcc by the 2 techniques in 191 DMD patients grouped according to age and severity of cardiac dysfunction: group B: DMD patients 10 years and younger with normal ejection fraction (EF); group C: DMD patients older than 10 years with normal EF; group D: DMD patients older than 10 years with reduced EF but negative myocardial delayed enhancement (MDE); group E: DMD patients older than 10 years with reduced EF and positive MDE; and group A: 42 control subjects. Retrospective, offline analysis was performed on matched tagged and steady-state free precession slices. Results: For the entire study population (N = 233), mean FT εcc values (−13.3 ± 3.8%) were highly correlated with HARP εcc values (−13.6 ± 3.4%), with a Pearson correlation coefficient of 0.899. The mean εcc of DMD patients determined by HARP (−12.52 ± 2.69%) and FT (−12.16 ± 3.12%) was not significantly different (p = NS). Similarly, the mean εcc of the control subjects by determined HARP (−18.85 ± 1.86) and FT (−18.81 ± 1.83) was not significantly different (p = NS). Excellent correlation between the 2 methods was found among subgroups A through E, except there was no significant difference in strain between groups B and C with FT analysis. Conclusions: FT-based assessment of εcc correlates highly with εcc derived from tagged images in a large DMD patient population with a wide range of cardiac dysfunction and can be performed without additional imaging. [Copyright &y& Elsevier]

Wstęp Diagnostyka urazów i ubytków funkcji nerwów obwodowych zarówno przed, jak i po leczeniu operacyjnym stanowi istotne wyzwanie przy podejmowaniu decyzji o dalszym postępowaniu. Wśród obecnie dostępnych metod jednoczesna ocena morfologii i funkcji nerwu wydawała się szczególnie trudna. Cel Wstępna ocena przydatności nowoczesnych metod obrazowania: HR USG oraz MRI DTI z aplikacją FiberTrak w diagnostyce morfologii i funkcji nerwów obwodowych. Materiał i metody Do badania zakwalifikowano 15 pacjentów po urazach nerwów przed lub po zabiegach rekonstrukcyjnych. Badania HR USG wykonywane były na aparacie Esoate MyLab 8 w celu oceny morfologii nerwu i wstępnej kwalifikacji do badania MRI, w tym wyznaczenia zakresu badania. Następnie wykonywano badanie MRI na aparacie Philips Ingenia o mocy 3T w sekwencjach T1, przed i po podaniu środka kontrastowego, T2 zależnych, PDW oraz DTI, które następnie poddano obróbce na stacji postprocessingowej z wykorzystaniem aplikacji FiberTrak. Uzyskane obrazy porównano z obrazem klinicznym. Wyniki W badaniu USG stwierdzono obecność 4 nerwiaków, 3 uszkodzeń ciągłości nerwu oraz 8 przypadków nerwów po zabiegach rekonstrukcyjnych. W badaniu MRI potwierdzono uzyskane wcześniej w USG wyniki, a ponadto w sekwencji DTI wykazano obecność ukierunkowanej dyfuzji w obrębie dystalnych części nerwów, w których stwierdzano w badaniu klinicznym cechy reinerwacji. Co ciekawe, we fragmentach nerwu rekonstruowanego przy użyciu neurotuby Neuragen nie stwierdzono obecności ukierunkowanej dyfuzji w obrębie regeneratu, pomimo wykazanego przewodnictwa w dystalnej części tego samego nerwu. Wykazano możliwą wysoką przydatność powyższych metod obrazowania, ze szczególnym wskazaniem na badanie traktografii nerwów w MRI. Wnioski Zarówno wysokorozdzielcza ultrasonografia nerwów obwodowych, jak i badanie rezonansu magnetycznego mogą stanowić źródło wartościowych informacji dotyczących morfologii uszkodzonego nerwu. Ponadto aplikacja FiberTrak, w oparciu o tensor dyfuzji, może pozwalać na ocenę funkcji nerwu i przewodnictwa zachodzącego w jego obrębie, co stanowi w połączeniu z obrazem morfologicznym przydatne narzędzie w kwalifikacji pacjentów do dalszego leczenia operacyjnego. [ABSTRACT FROM AUTHOR]

An abstract of the article "The comparison of mitral deformation indices and left ventricle geometry with quantitative assessment of ischaemic mitral regurgitation: echocardiographic and cardiovascular magnetic resonance study," by A. M. Lesniak-Sobelga and colleagues is presented.

Background: One of the main risk factors for cerebral ischemic events is atherosclerotic disease of the internal carotid artery (ICA). Nowadays, increasing attention is being paid to the relationship between the morphological features of atherosclerotic plaque and the occurrence of stroke. Several studies have demonstrated that the presence of specific vulnerable plaque types, with a large lipid core and thin fibrous cap, can be used as an independent risk predictor of cerebral ischemic events., Objectives: The present study is an attempt to develop the method of plaque surface morphology assessment presented by de Weert et al. by correlating the results of Dual Source Computed Tomography (DSCT) with those from intravascular ultrasound virtual histology (IVUS-VH)., Material and Methods: A group of 30 symptomatic patients (13 men and 17 women; 72 ± 9 years) with ICA stenosis suspected on the basis of ultrasound imaging (US) and confirmed to be above 70% in DSCT underwent intravascular ultrasound (IVUS) imaging., Results: The results of DSCT were categorized according to the de Weert classification. There were 13 cases (43%) with smooth wall surfaces, 10 cases (33%) with discreet wall irregularities, and seven cases (23%) with incursions of contrast, indicating the presence of ulceration. In the IVUS-VH examinations, 4 out of 30 cases (13%) were identified as having adaptive intimal thickening (AIT), 4 (13%) as showing pathological intimal thickening (PIT), 6 (20%) with fibroatheromas (FA), six (20%) with fibrocalcific plaque (FCa), and 10 (33%) as having thin-cap fibroatheroma (TCFA), which is high-risk plaque. Comparing the above results showed that all the patients with confirmed wall ulceration in DSCT were characterized as having high-risk plaque in IVUS-VH., Conclusions: Using DSCT with the de Weert classification of plaque surface morphology makes reliable detection of ulcerations possible; therefore, this could become a significant new technique to improve current imaging protocols for patients with a high risk of ischemic cerebrovascular events.

Background: Effective progenitor cell recruitment to the ischemic injury zone is a prerequisite for any potential therapeutic effect. Cell uptake determinants in humans with recent myocardial infarction are not defined. We tested the hypothesis that myocardial uptake of autologous CD34(+) cells delivered via an intracoronary route after recent myocardial infarction is related to left ventricular (LV) ejection fraction (LVEF) and infarct size., Methods and Results: Thirty-one subjects (age, 36-69 years; 28 men) with primary percutaneous coronary intervention-treated anterior ST-segment-elevation myocardial infarction and significant myocardial injury (median peak troponin I, 138 ng/dL [limits, 58-356 ng/dL]) and sustained LVEF depression at ≤45% were recruited. On day 10 (days 7-12), 4.3×10(6) (0.7-9.9×10(6)) (99m)Tc-extametazime-labeled autologous bone marrow CD34(+) cells (activity, 77 MBq [45.9-86.7 MBq]) were administered transcoronarily (left anterior descending coronary artery). (99m)Tc-methoxyisobutyl isonitrile (99(m)Tc-MIBI) single-photon emission computed tomography before cell delivery showed 7 (2-11) (of 17) segments with definitely abnormal/absent perfusion. Late gadolinium-enhanced infarct core mass was 21.7 g (4.4-45.9 g), and infarct border zone mass was 29.8 g (3.9-60.2 g) (full-width at half-maximum, signal intensity thresholding algorithm). One hour after administration, 5.2% (1.7%-9.9%) of labeled cell activity localized in the myocardium (whole-body planar γ scan). Image fusion of labeled cell single-photon emission computed tomography with LV perfusion single-photon emission computed tomography or with cardiac magnetic resonance infarct imaging indicated cell uptake in the peri-infarct zone. Myocardial uptake of labeled cells activity correlated in particular with late gadolinium-enhanced infarct border zone mass (r=0.84, P<0.0001) and with peak troponin I (r=0.76, P<0.001); it also correlated with severely abnormal/absent perfusion segment number (r=0.45, P=0.008) and late gadolinium-enhanced infarct core (r=0.58 and r=0.84, P<0.0001) but not with echocardiography LVEF (r=-0.07, P=0.68) or gated single-photon emission computed tomography LVEF (r=-0.28, P=0.16). The correlation with cardiac magnetic resonance imaging-LVEF was weak (r=-0.38; P=0.04)., Conclusions: This largest human study with labeled bone marrow CD34(+) cell transcoronary transplantation after recent ST-segment-elevation myocardial infarction found that myocardial cell uptake is determined by infarct size rather than LVEF and occurs preferentially in the peri-infarct zone.

One of the most common causes of stroke is carotid atherosclerosis, stroke affects about 60 thousand Polish people each year and about 27% of them die within a year. About 72%-86% are ischemic strokes, whereas intracerebral or subarachnoid haemorrhages account for about 9-18% of strokes. Stroke is the third most common cause of death worldwide, after heart disease and cancer, and the most often cause of chronic disability in people over 40. Carotid atherosclerosis is one of the most important stroke risk factors. The degree of stenosis is a standard parameter usually used in risk assessment. It was shown that patients with stenosis greater than 70% undergoing endarterectomy achieve the best results in reducing the risk of stroke compared with pharmacotherapy. However, it was found that in the general population of people over 64 the stenosis greater than 70% occurred in 10% of patients, while changes below 70% were very common and appeared in 70% of men and 60% of women. For this reason, the importance of atherosclerotic plaque morphology in the risk assessment is growing. Histopathological and ultrasound (intravascular ultrasound) morphological changes in the composition of the atherosclerotic plaque lead to the creation of the vulnerable plaque concept. Stroke risk seems to be connected with certain morphological features of the plaque, such as thin fibrous cap, lipid core, or ulceration. Ulceration is especially important, as 30% of those patients develop neurological symptoms within 2 years. On the other hand strong plaque calcification, particularly superficial, appears to pose lower risk. Ultrasound imaging of carotid arteries is currently the most widely used non-invasive diagnostic method for detecting and assessing the extent of carotid atherosclerosis. However, apart from undeniable advantages it also has its limitations such as the scope of the imaging and lower sensitivity and specificity in the evaluation of carotid stenosis in relation to magnetic resonance imaging and computed tomography (CT) as showed in metaanalyses from multicenter research (e.g. Chapel et al. metaanalysis). Previous studies using CT demonstrated the suitability of this method in the evaluation of morphology and significance of carotid arteries stenosis. Recent introduction of dual source multidetector computed tomography (DSCT) is a next technological step increasing the usefulness of CT in the assessment of plaque morphology. Due to simultaneous operation of 2 lamps the DSCT uses two concurrent X-ray sources (80 kv and 80 kV or 120 kV or 140 kV) to obtain different radiation absorption coefficients for a given tissue (in Hounsfield units). This allows for better tissue differentiation and advanced image processing, e.g. easy removal of bone parts for better visualization of vascular areas. This method also facilitates more accurate visualization of the lipid core and ulcerations. However, it should be emphasized that still relatively low spatial resolution of this method (0.6 mm) is a serious limitation to an accurate analysis of small structures, such as the components of the atherosclerotic plaque. Therefore, further comparative studies with other invasive diagnostic methods are necessary to improve the imaging protocols.

Conventional angiography of the coronary arteries is a standard in heart and coronary arteries diagnosis, sufficient to choose a treatment method. The introduction of 64-row multidetector computed tomography improved the imaging of coronary arteries by increasing its spatial and temporal resolution. It has been shown that the potential clinical value of CT angiography, including dual source computed tomography (DSCT), is based particularly on the exclusion of coronary artery disease and is now a recognized clinical indication in patients with equivocal stress test results. Detection of hemodynamically insignificant atherosclerotic plaques during CT angiography may be important from the clinical point of view. Rupture of those plaques is the reason of about 60% of acute coronary events. Myocardial infarction with ST-segment elevation is not an indication for CT angiography of the coronary arteries. Acute chest pain is the cause of approximately 6-8% of hospitalizations in the EU and the United States. According to the U.S. data about 50% of patients are admitted to a hospital for observation, and of those only 15% are finally diagnosed with acute coronary syndrome. On the other hand 2-5% of patients are incorrectly diagnosed and discharged home despite the occurrence of ACS. In spite of relatively frequent and easy to recognize symptoms, the subject literature states that diagnosis of more than 1/3 of patients with acute chest pain poses a considerable difficulty in the A&E departments. Problems with proper risk assessment and diagnosis of the disease result in unnecessary hospital admissions, implementation of expensive and often invasive diagnostic methods and generating costs borne by the health care system. There is a need to optimize the minimally invasive diagnostic methods, that allow reliable exclusion of coronary artery disease and acute coronary syndrome. In approximately 10 to 20% of all patients with chest pain neither ST segment elevation nor positive results of enzymatic tests are found, those are patients with low or intermediate risk of acute coronary syndrome. Currently, the most widely used diagnostic method in these patients is a stress test and other diagnostic tests. Coronary angiography and stress tests enable the detection of atherosclerotic lesions, which significantly narrow the artery lumen and reduce the myocardial perfusion. There is therefore the demand for a reliable and minimally invasive imaging method for assessing coronary arteries, which will enable excluding critical coronary artery stenosis or isolating, from a group of medium and low risk patients assessed with routine tests, those who should undergo immediate angiography and invasive treatment. CT angiography allows to assess the severity of coronary atherosclerosis. The possibility of vascular wall and plaque morphology evaluation may have a significant impact on the detection of atherosclerotic lesions of vulnerable character. CT angiography has already been used for the noninvasive assessment of plaque morphology in comparison with the standard, i.e. intracoronary ultrasound-ICUS. Intracoronary ultrasound is the most accurate method for the evaluation of stenosis and plaque morphology, but high costs and invasiveness limit its application. It is necessary to assess the extent to which the multidetector dual source computed tomography may be an alternative for the intracoronary ultrasound (ICUS). Recent years brought about extensive tests of a CT angiography diagnostic algorithm originally called "triple rule-out" (Scheme 1). This method refers to the population of patients without a definitive diagnosis after routine diagnostic tests. It is applied mainly to acute conditions with which a patient reports to the A&E department: myocardial infarction, pulmonary embolism, aortic dissecting aneurysm as well as changes in the chest and ascending aorta and pulmonary arteries. The authors of this paper deem it necessary to conduct further clinical trials on the usefulness and cost-effectiveness of CT angiography in different patient groups.

We conducted a cross-sectional observation study that included 500 asymptomatic subjects to investigate the relationship between bone metabolism and coronary artery calcification (CAC) in hypertensive conditions. Osteoprotegerin (OPG) and osteopontin (OPN) levels and their associations with hypertension were analyzed to predict CAC in 316 subjects. Multislice computed tomography was used to quantify CAC. Multivariate analysis of variance was used to test the non-interactive effects of hypertension, CAC severity and biomarker levels, and the logistic regression model was applied to predict the risk of CAC. OPG and OPN concentrations were significantly higher in the hypertensive than the normotensive subjects, at 3.0 (2.3-4.0) pmol l(-1) and 51 (21-136) ng ml(-1) vs. 2.4 (2.0-3.0) pmol l(-1) and 41 (13-63) ng ml(-1), respectively. The OPG level, but not OPN level, increased with age (r = 0.29; P = 0.0001). Zero or minimal CAC (<10 Agatston units (AU)) was observed in 63% of the subjects, mild (11-100 AU) in 17%, moderate (101-400 AU) in 12% and severe (401-1000 AU)-to-extensive (>1000 AU) in 8%. In hypertensive subjects, only glomerular filtration rate (GFR) (β = -0.67) and gender (β = 0.52) were significant predictors for CAC (R = 0.68). In normotensive patients, GFR (β = -0.81), gender (β = 0.48) and log-transformed OPG levels (β = 0.15) were significant predictors for CAC. OPG levels were associated with an increased risk of CAC in normotensive subjects only (odds ratio: 3.37; 95% confidence interval (1.63-6.57); P = 0.0002). OPG predicted a premature state of vascular calcification in asymptomatic normotensive individuals, and renal function significantly contributed to this process in both hypertensive and normotensive subjects.