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R Marano

Publications and source records attributed to R Marano.

At least 19 recordsLinked to original sources
PubMed1999

Contrast-enhanced MR angiography (CE MRA) in the study of the carotid stenosis: comparison with digital subtraction angiography (DSA).

PURPOSE: To determine sensitivity, specificity and diagnostic accuracy of contrast-enhanced magnetic resonance angiography (CE MRA) compared to digital subtraction angiography (DSA) in the study of carotid stenosis. METHODS AND MATERIAL: We studied 23 patients with suspected cerebro-vascular insufficiency by carotid stenosis. Diagnostic examinations by means of CE MRA and DSA were carried out within 24 hours of each other. A 1.5 T superconductive magnet (Signa-General Electric) was used for CE MRA. This technique was performed using a fast spoiled gradient echo recalled (SPGR) sequence acquired in coronal plane 13 sec after injection of contrast medium. Imaging parameters were: TR/TE/FA 8 msec/1 msec/60 degrees, matrix 256 x 128, 1 excitation, FOV 18 x 13 cm, 28 slices per slab, slice thickness of 1 mm, acquisition time of 32 sec. The post-processing was performed using maximum intensity projection (MIP) and targeted MIP. For DSA examinations a Politron 1000 VR unit (Siemens) was used. RESULTS: In the identification and quantification of lesions, CE MRA showed values of 100%. In particular, in comparison to DSA, CE MRA was accurate in diagnosing all true negative and positive cases. The location of stenosis evaluated with CE MRA agreed in all cases with DSA. CONCLUSION: In our experience CE MRA proved to be a very valuable technique in diagnosing carotid stenosis, showing the same diagnostic accuracy as DSA. In this way CE MRA appears to be a substantial alternative technique to conventional MRA and other non-invasive diagnostic methods.

Aged↗
PubMed1998

Pulmonary veins: magnetic resonance angiography anatomy.

OBJECTIVE: to optimize magnetic resonance angiography technique for the selective study of the anatomy of pulmonary veins. MATERIALS AND METHODS: twenty consecutive patients (13 males and seven females; mean age 30.5 years) prospectively studied were enrolled. Magnetic resonance angiography was performed using a 1 T superconductive magnet and three dimensional time of flight technique (3D TOF). Imaging with steady-state free precession sequence during intravenous infusion of contrast medium (Gd DTPA 0.2 mmol kg(-1)) administration was employed using the following parameters: FA 20 degrees, TR 58 ms, TE 6 ms, MA 192 x 256, NEX 1, slice thickness 4 mm and slice orientation on the Z and Y planes. RESULTS: in the right lung magnetic resonance angiography well visualized 124 venous vessels on the coronal plane versus 106 venous vessels on the sagittal plane, whereas in the left lung magnetic resonance angiography visualized 96 vessels on the coronal plane versus 44 visualized on the sagittal plane. Our data suggest that 3D time of flight with contrast medium is a promising evaluation technique for pulmonary veins, and that combined evaluation of acquisitions on coronal and sagittal planes allows the visualization of a higher number of venous vessels. CONCLUSION: 3D time of flight with contrast medium and without breath-hold permits to visualize a venous vascular map of the lungs.

Adult↗
PubMed1998

High-resolution magnetic resonance angiography of the internal carotid artery: 2D vs 3D TOF in stenotic disease.

The aim of this study was to compare high-resolution 2D TOF with high-resolution 3D TOF in the study of internal carotid artery disease. Sixty-four patients with clinical signs of cerebrovascular insufficiency were studied with a superconductive 1.5 T magnet using two techniques: 2D and 3D TOF. Digital subtraction angiography (DSA) was the gold standard. The 2D TOF technique was performed using the following parameters: TR/TE/FA/MA 49 ms/9 ms/60 degrees/512 x 256; the 3D TOF was performed with the following parameters: TR/TE/FA/MA 50 ms/8 ms/20 degrees/512 x 256. The 2D TOF agreed with DSA in 116 of 128 diagnostic judgments (90%) and overestimated seven times. The 3D TOF technique agreed with DSA in 125 of 128 diagnostic judgments (97%) with one overestimation and two underestimations. There was no statistically significant difference (P < 0.05) between the two different techniques. Our study confirms the high reliability of the methodology carried out with the high-resolution 2D and 3D technique.

Angiography, Digital Subtraction↗
PubMed1998

[Angiography compared to high resolution magnetic resonance and digital angiography in atherosclerosis of the iliac-femoral arteries].

INTRODUCTION: Magnetic Resonance Angiography (MRA) potentials in all vascular districts have been largely applied also to peripheral vessels, where however there is no agreement as to the best type of sequence. We investigated the sensitivity, specificity and diagnostic accuracy of 2D TOF travel-sat MRA in the study of iliac-femoral artery stenoses. The gold standard was digital subtraction angiography (DSA). MATERIAL AND METHODS: Twenty patients (14 men and 6 women, mean age: 65 years with suspected atheromasic disease were examined. Diagnostic MRA and DSA were carried out within 48 hours of each other. A super-conductive 1 T magnet (Siemens Impact) and a body coil were used. 2D TOF travel-sat sequences were carried out with the following parameters: FA 40 degrees, TR 31 ms, ST 10 mm, overlap 1 mm, MA 128 x 512. The images acquired on the axial plane were postprocessed with MIP on the z axis from -15 degrees to 15 degrees. Two different radiologists evaluated MRA and DSA images and graded the stenoses on a multiple choice card: 1) negative, 2) 1-40%, 3) 41-70%, 4) 71-99%, 5) occlusion. RESULTS: MRA diagnosed 90 positives and 110 negatives: 60 were true positives, 92 true negatives, 30 false positives and 18 false negatives. MRA overestimated 8 cases and underestimated 4 cases. DSA findings were negative in 122 cases and positive in 78 cases: 4 grade 2, 10 grade 3, 28 grade 4 and 36 grade 5. Relative to DSA, MRA sensitivity, specificity and diagnostic accuracy were 72%, 75% and 74%, respectively; MRA diagnostic accuracy, sensitivity and specificity in hemodynamically severe stenoses (> 71%) were 80%, 78% and 71.8%, respectively. CONCLUSION: Our study confirms the usefulness of 2D TOF travel-sat MRA in the study of iliac-femoral stenoses.

Adult↗
PubMed1998

[Angiography with magnetic resonance of the body with contrast media. Experience with a 0.5 tesla device].

INTRODUCTION: We optimized the technique of contrast-enhanced Magnetic Resonance Angiography (MRA) with a .5 T superconductive magnet. MATERIAL AND METHODS: Forty patients with normal blood pressure and heart rate gave their informed consent to MRA studies with contrast agent administration. The carotid arteries were studied in 10 patients, the pulmonary arteries in 10, the thoracic aorta in 10 and the abdominal aorta and renal arteries in 10. All the examinations were performed with a .5 T superconductive magnet (Philips T5) acquiring 3D T1-weighted GE sequences with contrast agent administration. The parameters were: TR/TE/FA 13 ms/4 ms/60 degrees; 256 x 256 MA; 2 mm slice thickness; 1 NEX. The contrast agent was administered with an automatic injector (.2 mmol/kg at 1.5 flowrate) after a bolus test to evaluate circulation time. The images were studied by a radiologist rating artery visualization as "good" or "poor" on a multiple choice card. The signal-to-noise ratio was evaluated using regions of interest positioned on the examined vessels (signal) and muscles (noise). RESULTS: The mean start delay was 12.2 s for the abdominal aorta, 10.3 s and 8.7 s for the thoracic aorta and pulmonary arteries, and 10.3 for the carotid arteries. Fifty-eight of 70 vessels were well visualized and 12 were poorly visualized. The signal-to-noise ratio exceeded 1 in all districts. CONCLUSIONS: Our experience shows that enhanced MRA provides diagnostic images of body arteries even at .5 T.

Adult↗
PubMed1998

Vasodilating in MR-angiography: a comparison of techniques.

PURPOSE: To verify the hypothesis that a drug that causes vasodilation can contribute to improvement in MRA spatial resolution. To test this hypothesis, a comparison was made between the images obtained using the high resolution time-of-flight (TOF HR 3D) technique and the TOF 3D MTC TONE technique. METHODS: From November 1993 to December 1994, we studied 40 patients, of which 20 patients (16 males and 4 females; average age of 10 years; range from 3 to 20 years) we examined after they had inhaled Isoflurane (experimental group), and 20 patients (16 males and 4 females; average age 9.7 years; range from 3 to 12 years) were examined with standard MRA (control group). RESULTS: The vasodilator in both HR MRA and MTC TONE MRA permits a better spatial visualization with respect to the clinical routine MRA. On the other hand, it is true that MTC TONE gives better visualization of the small vessels. DISCUSSION: In our experience, this preliminary study indicates that with respect to routine MR, the spatial resolution is notably increased when Isoflurane is used. The signal-to-noise ratio is increased but, moreover, the ability to visualize small vessels is increased. CONCLUSION: The preliminary results obtained in this study indicate that a pharmacological drugs is capable of increasing the vascular detail of MRA images of the intracranial vessels and that continued research this direction is called for.

Adolescent↗
PubMed1997

[Choledocholithiasis: semeiotic and diagnostic accuracy of cholangiography with magnetic resonance].

The authors report their experience in the optimization of the diagnostic accuracy of Magnetic Resonance Cholangiography (MRC) to detect choledochal stones; pre- and post-MIP post-processing images were compared. Thirty patients with dilated biliary ducts (mean age: 55.6 years) were examined with MRC; two of them had stones in the intrahepatic biliary ducts. The gold standard and the inclusion criterion was ERCP. MRC was carried out with a 1.5 T superconductive magnet (Signa) with T2-weighted FAST SE sequences (TR/TE; 10000/256, matrix: 256 x 128, slice thickness: 3 mm, TA: 6 min 28 s). Coronal MR images were blindly studied before and after MIP post-processing; Friedman's test was used for statistical analysis (p < .05). ERCP showed 92 cases of choledocholithiasis, with the stones ranging .2 to 3.4 cm; MRC before MIP post-processing had 97.1% diagnostic accuracy, 97.8% sensitivity and 95.8% specificity. These values are significantly different from those obtained after MIP (91.4%, 86.9% and 95.8% respectively). In our experience, pre- and post-MIP post-processing MRC can be considered a reliable and accurate noninvasive technique to detect choledochal stones.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1996

Familial intracranial hypertension: a case report.

We report the cases of a father and his daughter developing idiopathic intracranial hypertension within a few months' of each other. A second daughter is affected by uveitis, while a third daughter presented an episode of visual loss of unknown nature.

Adolescent↗
PubMed1996

[Anatomico-functional correlations between the pulmonary and portal circulations: the prerequisites for a modern functional imaging diagnosis].

This study was aimed at investigating the current knowledge on the similarities between pulmonary and portal circulation to try to improve the diagnostic capabilities of functional radiology in these two districts. These two organs are similar both from an anatomical and a functional viewpoints, sharing the same microarchitecture and a double vascular system with similar hemodynamic characteristics. In the past, the parameters to evaluate pulmonary flow and pressure consisted in the analysis of the distribution, diameter and number of vessels with conventional radiology, but today, HRCT permits the regional assessment of perfusion and air volume, using density values. Dynamic density changes (expiratory and prone scanning), together with the morphological features of peripheral bronchial and vascular structures, play a fundamental diagnostic role in differentiating small airway conditions from normal and hemodynamic changes. When HRCT shows a "mosaic" pattern--i.e., regions with different density values--reduced perfusion can be distinguished, because in this case hypodense areas are vascularized by fewer, and smaller, vessels. Expiratory scanning can exclude abnormal ventilation. Hyperperfusion is characterized by higher density areas vascularized by more, and bigger, vessels. Doppler US and MRA show, once again, their limitations in calculating the absolute values of flow velocity and flow volume in the splanchnic district; in clinical studies, only the semiquantitative data yielded by Doppler US are considered reliable. Therefore, also in this district, relative data must be preferred to absolute ones; for instance, it is interesting to analyze the hemodynamic changes occurring in patients under different physiologic or experimental conditions. We believe that, in the near future, technological progress and growing operators' skills will make functional radiology a major tool helping the clinician approach and treat these patients correctly.

Humans↗
PubMed1996

Morphological and molecular characterization of Giardia isolated from the straw-necked ibis (Threskiornis spinicollis) in Western Australia.

Following the first report of avian Giardia infection in Australia, isolates of the parasite recovered from naturally infected straw-necked ibis (Theskiornis spinicollis) were characterized using median body morphology, scanning electron microscopy, multilocus enzyme electrophoresis, random amplified polymorphic DNA (RAPD), and small subunit ribosomal RNA (SSU-rRNA) analyses. Results were compared with Giardia from other birds and mammals, and the extent of genetic diversity between a range of ibis isolates collected in Western Australia was determined. The ibis isolates of Giardia were genetically relatively homogeneous, which is in contrast to the extensive genetic heterogeneity often displayed by mammalian Giardia isolates. Morphologically, Giardia from ibis were similar to Giardia ardeae although they differed genetically and by the fact that the ibis isolates could not be established in in vitro culture. Sequence data of the DNA coding for the SSU-rRNA found a 96% homology between the ibis isolates from Western Australia and G. ardeae, suggesting that they represent distinct strains of the same species. In contrast, the ibis isolates were genetically and morphologically very different than Giardia duodenalis and Giardia muris from mammals.

Animals↗
PubMed1994

Protein expression using cotranslational fusion and cleavage of ubiquitin. Mutagenesis of the glutathione-binding site of human Pi class glutathione S-transferase.

Expression of cloned genes in prokaryotes such as Escherichia coli is a widely used technique in both basic research and biotechnology. Despite the availability of several E. coli expression vector systems, adequate levels of expression may not be achieved. Expressing proteins as fusions to the highly conserved eukaryotic protein ubiquitin has been reported by several investigators to enhance protein yield in both bacterial and eukaryotic systems. We have modified this technique by the co-expression in E. coli of a ubiquitin-fusion protein and the Saccharomyces cerevisiae ubiquitin-specific protease Ubp2. This allows the co-translational cleavage of engineered ubiquitin-fusion proteins expressed in E. coli. This system was used to express a human Pi class glutathione S-transferase (GST) GSTP1 as well as two mutant GSTP1 derivatives, Trp39-->Cys and Gln52-->Glu. The yield of these enzymes was improved 40-fold by using the ubiquitin-fusion/co-translational cleavage technique, and no uncleaved product was detected. The Trp39-->Cys mutant was totally devoid of GST activity, while the activity of the Gln52-->Glu mutant was reduced to 6% of wild-type GSTP1-1. As both of the mutated residues map within the glutathione-binding site, the reduced GST activity is consistent with a marked reduction in glutathione binding ability.

Amino Acid Sequence↗
PubMed1989

A case of Refsum disease with atypical clinical picture in family members.

A typical case of Refsum disease with high phytanic acid plasma levels is described. Two siblings showed some features but not the entire clinical spectrum of the disease. The unusual condition of the patient's father, a presumed heterozygotic carrier with characteristic bone abnormalities and a delayed onset retinopathy, is discussed.

Adult↗
PubMed1988

Relationship between motor and cognitive disorders in Huntington's disease.

Akinesia and mental decline appear to be more appropriate criteria than hyperkinesia for the evaluation of the stage and progression of Huntington's disease (HD). In order to establish the relationship between motor and cognitive impairment in the disease, 20 non-demented HD patients were compared with 44 control subjects with respect to motor and cognitive performance. HD patients were significantly impaired in almost all cognitive functions in comparison with controls. Reaction time (RT) and movement time (MT) were considerably slower in HD patients when compared with controls and with patients with parkinsonism. Hyperkinesias did not correlate with cognitive impairment, but there was a good correlation between RT, MT and cognitive functions. Therefore, it seems that akinesia evaluated by RT and MT is an important sign in HD and proceeds at the same rate as mental decay.

Adult↗
PubMed1986

Motor and cognitive performances of parkinsonian patients in the on and off phases of the disease.

Twenty-one Parkinsonian patients were tested in on and off phases during chronic levodopa therapy for cognitive function, affective status, and evaluation of motor performance with reaction and movement times. A worsening of mood was observed from the on to the off phase. No variation in cognitive performance was observed from the on to the off phase in spite of evident motor changes. Mood changes during on-off variations may reflect involvement of mesocortical and mesolimbic dopaminergic systems.

Affect↗
PubMed1986

Cognitive impairment in Parkinson's disease.

Neuropsychologic studies on Parkinson's disease have shown an impairment of specific cognitive functions and a greater evidence of dementia. Cognitive alterations are related to the gravity of some peculiar motor symptoms of the disease and show a major role of motor disturbances in intellectual disorders. The concept of bradyphrenia and subcortical dementia still seems to be suitable to define the cognitive disorders of Parkinson's disease.

Cognition Disorders↗