Diagnosis and outcome of renal function in patients with renal artery stenosis: which role have color Doppler sonography and magnetic resonance angiography?

Aim: Minimally invasive diagnostic techniques would be useful in the preoperative diagnosis of patients with hypertension and ischemic renal disease. The aim of our study was to compare color Doppler sonography (CDS), and magnetic resonance angiography (MRA) with the reference standard, digital subtraction angiography (DSA), in the diagnosis of renal artery stenosis.

Methods: Thirty-nine patients with arterial hypertension and monolateral or bilateral renal artery stenosis documented by CDS underwent renal artery MRA and then DSA during corrective percutaneous transluminal angioplasty.

Relationship of asymmetric dimethylarginine to haemodialysis hypotension.

Hypotension is one of the major complications in patients undergoing haemodialysis (HD), that is well evident in patients defined as "hypotension-prone." The mechanisms underlying the hypotensive episodes are not known. We carried out a clinical study on hypotension-prone HD patients to test the existence of a dysregulation in the nitric oxide (NO) generating pathway.

Low-contrast medium doses for ultrasound imaging during renal revascularization by PTA-stenting.

Background: To evaluate the incidence of progressive renal damage in patients with chronic renal insufficiency and renal-artery stenosis undergoing percutaneous transluminal angioplasty and stenting (PTA-stenting), color Doppler ultrasound (CDU)-guided, a procedure requiring low-contrast medium doses, or digital subtraction angiography were compared.

Methods: Thirty patients with renal artery stenosis and severe renal insufficiency underwent PTA-stenting for revascularization, 15 patients with CDU guidance and 15 patients with standard selective digital subtraction angiography (SDSA). Serum creatinine (Cr) concentrations were compared in the two groups at 6 days and 12 months after revascularization.

Effect of alpha-tocopherol and N-acetylcysteine on benzoyl peroxide toxicity in human keratinocytes.

Benzoyl peroxide is a free-radical generating compound widely used in the polymer industry and also in pharmaceuticals as antimicrobial agent to treat acne. However, benzoyl peroxide causes irritation and contact dermatitis in about 1% of patients. Concern over the use of this compound is motivated by the demonstration that it can also act as skin tumor promoter in mice.

Color Doppler ultrasound guidance during renal angioplasty and stenting.

Purpose: To investigate whether an imaging technique combining color Doppler ultrasonography and selective renal artery digital subtraction angiography reduces contrast requirements in patients with progressive renal insufficiency undergoing renal artery angioplasty and stenting.

Methods: Eight patients (5 men; mean age 58 years) with renal artery stenosis and renal insufficiency underwent percutaneous transluminal angioplasty and stenting under color Doppler ultrasound guidance.

Results: Color Doppler ultrasound imaging yielded the information necessary for verifying catheter position, stent placement and expansion, and hemodynamics after revascularization.

Suprarenal artery stenosis may be mistaken for renal artery stenosis in Doppler studies.

There are several limitations in using colour-flow-Doppler (CFD) to diagnose renal artery stenosis. This report describes a case of "false positive" stenosis of the renal artery diagnosed using CFD. A patient affected by arterial hypertension and with a suspected stenosis of the renal artery was examined using CFD.

Epidermal growth factor receptor polymorphism and autosomal dominant polycystic kidney disease.

Background: The clinical variability in the rate of progression of autosomal dominant polycystic kidney disease (ADPKD) has been attributed to genetic heterogeneity, though environmental factors and modifying genes very likely play an important role as well. We examined the association between clinical outcome, defined by age at onset of end-stage renal disease (ESRD) in 46 ADPKD patients, and a polymorphism in the epidermal growth factor receptor (EGFR) gene, a candidate modifying gene. EGFR is a key element in renal tubular proliferation.

Could an echo contrast agent be helpful in identifying renal artery stenosis?

Background: Diagnosis of renal artery stenosis using echo color-Doppler is subjected to several limitations. The aim of this study was to examine if the routine use of a contrast agent could be helpful in identifying renal artery stenosis (RAS).

Methods: We analysed 35 patients affected by RAS using an echo color-Doppler coupled with a contrast agent.

[Comparison of 0.125% bupivacaine and 0.2% ropivacaine in obstetric analgesia].

This comparative study of low doses of ropivacaine was conducted in order to identify the most effective form of analgesia during labour with the aid of supplementary low doses of fentanyl and clonidine. 60 ASA I and II parturient primipares who had asked for epidural analgesia were randomly assigned to two groups. Group R was given 5-7 ml 0.

Color-Doppler sonography in ophthalmology.

Background: With the present study we considered ocular blood flow by the use of color Doppler ultrasound. We compared the most clinically important arteries of both eyes. We valued the central retinal artery, the posterior long ciliary arteries, the posterior brief ciliary arteries and the central retinal vein.

[Penile ultrasonography. Characteristic velocimetric feature in the maximal erection phase in healthy subjects].

Background: A peculiar finding from penis eco color-Doppler, detected in healty subjects with erection dysfunction, is described.

Methods: 385 patients with erection dysfunction were studied, by using duplex scan with color Doppler, 85 of these patients normal Regiscan test were chosen and patients with Induratio penis plastica or hormonal disorder were excluded.

Results: A "reverse" flow during the entire diastolic phase was detected in 58 normal patients (68%) with age < of 41 years.

Poroelastic finite element analysis of a bone specimen under cyclic loading.

It had been suggested that the fluid embodied in bone lacunar-canalicular porosity may play an important role in bone remodelling [Weinbaum et al., 1994. Journal of Biomechanics 27, 339-360].

Antineutrophil cytoplasmic antibodies in autoimmune thyroid disorders.

Different antibodies against both organ- and non-organ-specific autoantigens have been found in patients with autoimmune thyroid diseases. The aim of our study was to evaluate the presence of antineutrophil cytoplasmic antibodies (ANCA) in sera of patients affected by Graves' disease (GD) and Hashimoto's thyroiditis (HT). These antibodies were investigated by indirect immunofluorescence; the reactivity against myeloperoxidase and lactoferrin was assessed by ELISA.

[Indirect diagnosis of aortic coarctation by Doppler color echography. Velocimetric and spectral aspects in one of our cases].

Objective: Description of a case report.

Patients: The case of a 55-years-old man with a previous history of hypertension, treated for several years with many antihypertensive drugs without improvement is described.

Results: The patient was affected with a unknown coarctation of the aorta.

Vascular endothelial growth factor: a key mediator of neoangiogenesis. A review.

Vascular endothelial growth factor (VEGF) is a multifunctional cytokine that exerts in vivo a key role in physiological and pathological neoangiogenesis by stimulating endothelial cell proliferation and vessel hyperpermeability. VEGF exists as one of four different isoforms, respectively, VEGF 121, VEGF 165, VEGF 189, VEGF 206, and seems to be a crucial mediator of physiological neoangiogenesis during the embryonic development and the female cycle. VEGF also has a major role in the pathogenesis of many diseases including hypervascularized tumors, rheumatoid arthritis, cutaneous diseases and proliferative retinopathies.