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Biomedical subjects

S Vinci

Publications and source records attributed to S Vinci.

At least 19 recordsLinked to original sources
PubMed2006

Role of coronal oblique reconstruction as a complement to CT study of the temporal bone: normal anatomy.

PURPOSE: The purpose of this study was to demonstrate the usefulness of coronal oblique multiplanar reconstruction computed tomography (MPR CT) reformation parallel to the basal turn of the cochlea in the evaluation of the retrotympanum and hypotympanum to complete the standard CT examination of the temporal bone obtained with axial and coronal images. MATERIALS AND METHODS: We studied 30 patients aged 18-79 years for a total of 60 normal petrous pyramids. All examinations were performed on a multislice CT (MSCT) scanner (Sensation 16, Siemens, Erlangen, Germany) with axial volumetric acquisition and completed with reformations of coronal and coronal-oblique images. MSCT scan parameters for axial acquisition were set as follows: 0.75-mm scan collimation, FOV 300 mm, 170 mAs. Axial images were reconstructed at 0.7-mm thickness and with a reconstruction increment of 0.5 mm using a high-resolution bone algorithm. RESULTS: Coronal oblique MPR CT reformations provided additional information with respect to standard CT images in all cases. In particular, they enabled measurement of the craniocaudal and laterolateral diameters of the sinus tympani. In all cases, there was optimal visualisation of the ponticulus and subiculum. Analysis of the pyramidal eminence was improved thanks to its visualisation in profile. Moreover, we obtained an optimal representation of the hypotympanum, which was always exhaustively explored with only one reconstruction. Finally, in all cases, it was possible to identify the facial nerve canal and main vascular structures and to measure the distance between these and the sinus tympani, pyramidal eminence and hypotympanum. The coronal oblique CT reformation was of no advantage in the evaluation of the fossa of the oval window and the niche of the round window. CONCLUSIONS: Coronal oblique MPR CT reformation should not be considered an alternative to the standard CT examination, but it can represent a valid integration to provide additional information on particularly crucial districts characterised by frequent involvement of inflammatory and/or expansile disease and because of their difficult endoscopic approach. Moreover, it can represent a meaningful aid to optimise surgical planning thanks to its different perspectives of observation.

Adolescent↗
PubMed2006

SDH mutations in patients affected by paraganglioma syndromes: a personal experience.

Mutations in genes encoding mitochondrial succinate dehydrogenase (SDH) are frequently involved in the development of neural crest-derived (NCD) tumors, such as pheochromocytomas (PHEOs) or paragangliomas (PGLs). In this study we report the results of sequencing analysis in leukocyte DNA of patients affected by PHEO/PGL who turned out to be SDH mutation carriers. A nonsense germline heterozygous mutation (Q109X) was found in the exon 4 of the SDHD gene in the index cases of six unrelated families affected by PHEO/PGL. Haplotype analysis showed the presence of a founder effect. Affected patients showed high clinical variability, ranging from monolateral to bilateral glomus tumors, variably associated or not with PGLs or PHEOs. A novel missense SDHD variant, T112I, was also found in one of our families. A new missense G106D mutation, involving a highly conserved amino acid, was found in two sisters affected by bilateral glomus tumors. A P81L mutation associated with abdominal and head and neck PGL was detected in three families. A G12S variant of the SDHD gene was found in one patient affected by a PHEO. The finding of this variant in 3 of 100 control subjects suggests that it is a polymorphism and not a mutation. A novel IVS2-1G>T variant was found at intron 2 of SDHD gene in one patient affected by a glomus tumor. All the tumors associated with SDHD mutations were benign. Conversely, the only mutation we found in SDHB gene (IVS3+1G>A) was associated with a malignant PHEO.

Amino Acid Sequence↗
PubMed2002

Cerebral angiography in the rat with mammographic equipment: a simple, cost-effective method for assessing vasospasm in experimental subarachnoid haemorrhage.

We report quantification of vasospasm following subarachnoid haemorrhage (SAH) and the effect of a new antivasospastic free radical scavenger (AVS) in rats, using an angiographic technique developed in our laboratory. We acquired single-exposure angiograms with mammographic equipment, using a 0.1 mm diameter focal spot and single-emulsion mammographic films. Contrast medium was injected through a PE50 catheter in the common carotid artery, after the external carotid artery had been ligated to divert flow towards the internal carotid artery territory. Measurements of the M1 and A1 segments and of the middle third of the basilar artery were made by projecting the angiograms directly as slides and using the endovascular catheter as an internal reference. We tested the technique on 40 male albino Sprague-Dawley rats divided into four groups: sham-operated+saline, SAH+saline, sham-operated+AVS and SAH+AVS. We were able to measure the diameter of the principal intracranial arteries in all the animals. With our technique, which is cost-effective when compared to many of those reported recently, we could detect intracranial vasospasm in all untreated rats with SAH, and confirm antivasospastic effects of AVS.

Animals↗
PubMed2001

Ossifying lipoma of the parapharyngeal space: CT and MRI findings.

Ossifying lipomas independent of bone tissue are very rare. A literature review revealed that only few cases of ossifying lipoma independent of bone tissue have been reported. None of the cases have been reported in the international radiology literature. In addition, there are no reports concerning the MRI features of this entity. We describe CT and MRI findings in a case of ossifying lipoma of the parapharyngeal space.

Diagnosis, Differential↗
PubMed2001

MR pyelography in 115 patients with a dilated renal collecting system.

PURPOSE: To evaluate the accuracy of MR pyelography in the assessment of hydroureteronephrosis. MATERIAL AND METHODS: One hundred and fifteen patients, with variable degree of hydroureteronephrosis demonstrated by US and urography were subjected to MR pyelography obtained by means of two ultra-fast sequences. RESULTS: Of the 228 kidneys examined, the collecting systems of 130 kidneys were dilated and correctly identified on MR pyelography, with only 2 false-positive results. The specificity of MR pyelography in detecting hydronephrosis was 98%. Accuracy in revealing level of obstruction was 100%. Sensitivity in detecting stones, strictures and congenital ureteropelvic junction obstructions was respectively 68.9%, 98.5% and 100%. CONCLUSION: MR pyelography can rapidly and accurately depict the morphological features of dilated urinary tracts with information regarding the degree and level of obstruction, without using contrast medium or ionizing radiation.

Adolescent↗
PubMed2001

Norepinephrine reuptake is impaired in skeletal muscle of hypertensive rats in vivo.

Certain forms of experimental hypertension are characterized by organ-specific alterations of catecholaminergic pathways. The purpose of this study was to evaluate, in the same awake and freely moving normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) before and after the development of arterial hypertension, the norepinephrine (NE) turnover and, in particular, the neuronal NE reuptake activity that ends its effects once released from nerve terminals, in subcutaneous adipose tissue and in skeletal muscle, whose sympathetic efferents are respectively independent or dependent from baroreflexes. Plasma and tissue interstitial NE and 3,4-dihydroxyphenylethylene glycol (DHPG), its major deaminated metabolite, were measured before and after blockade of NE reuptake by tissue perfusion of desipramine through microdialysis probes. Arterial pressure and plasma NE in SHR were similar to those in WKY at 5 weeks of age but increased at 16 weeks of age. In contrast, plasma DHPG was already higher in young SHR. Basal interstitial NE and DHPG were increased in both tissues of young and old SHR compared with age-matched WKY. Desipramine induced a higher rise of interstitial NE in SHR of both ages, with a lesser increase in the skeletal muscle of old compared with young SHR. These results indicate an increased NE turnover in prehypertensive and hypertensive SHR in both baroreflex-dependent and -independent tissues, not shown by plasma NE levels in young SHR. In the skeletal muscle, where sympathetic efferents are baroreflex dependent, the reduced interstitial NE reuptake contributes to the higher availability of interstitial NE for postsynaptic effects in old SHR.

Adipose Tissue↗
PubMed2000

Magnetic resonance imaging of bronchioloalveolar carcinoma.

The purpose of this study is to describe the magnetic resonance (MR) features of bronchioloalveolar carcinoma. MR examinations of 18 patients with proven bronchioloalveolar carcinoma were reviewed. Detection at computed tomography (CT) and pathologic confirmation were the entry criteria. Nine patients had a solitary nodule, three patients a lobar consolidation, and six patients had diffuse disease. For each patient, both breath-hold T2-weighted fast spin-echo, and breath-hold T1-weighted gradient-echo images, before and after injection of gadolinium, were available. Nine patients with pulmonary consolidation or diffuse disease had also heavily T2-weighted MR imaging (Haste or TSE 240; Siemens, Erlangen, Germany). MR imaging showed pulmonary abnormalities in 17 of 18 patients. Unenhanced T1-weighted and T2-weighted images depicted tumor in 16 of 18 patients. Contrast-enhanced T1-weighted images showed tumor in 17 of 18 patients. In no case did MR imaging depict abnormalities corresponding to the ground-glass opacities seen on CT scans. In three patients with mucinous bronchioloalveolar carcinoma, heavily T2-weighted images showed lesions isointense with respect to static fluid of the human body. In conclusion, the ability of MR imaging in detecting small nodules and ground-glass opacities is limited. However, heavily T2-weighted sequences are able to show the presence of mucin. This is useful information because mucinous bronchioloalveolar carcinoma carries a poor prognosis.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed2000

[Doppler power with contrast media in the characterization of renal masses].

PURPOSE: To report the results of a prospective study investigating the potentials of contrast-enhanced power Doppler in the diagnosis of expansive renal lesions. MATERIAL AND METHODS: From 1997 to October 30, 1999, we studied 59 expansive renal lesions (28 malignant, 31 benign) in 48 patients (mean age 55 years, range 10-79) with power Doppler US before and after the administration of an echo-enhancing agent (Levovist, Schering AG, Berlin, Germany). We identified 5 patterns of vascular architecture of the lesions, both before and after contrast agent administration, following the classification by Jinzaki e Coll. RESULTS AND DISCUSSION: Power Doppler US showed vascular structures in 34 patients. The administration of Levovist revealed vessels in 12/25 lesions which had none at baseline studies and in 6 cases vascularity was particularly evident. Color signals were enhanced in all the 34 vascularized lesions, which allowed better definition of vascular patterns. The characterization of vascular patterns with baseline power Doppler US helped improve diagnostic accuracy compared to gray-scale US (58% versus 32%) for hyperechoic lesions, complex cysts and pseudomasses. Independent of contrast agent administration, the integration of gray-scale and power Doppler modes increased diagnostic accuracy even further (76% correct diagnoses). CONCLUSIONS: In our series, the US contrast agent did not increase the diagnostic accuracy of power Doppler in the differential diagnosis of hyperechoic renal lesions; conversely, Levovist can be advantageous for the characterization of suspected pseudomasses and complex cysts.

Adolescent↗
PubMed1999

Hypertension as an etiopathological factor in the development of cerebral atrophy in hemodialyzed patients.

Twenty-five patients on long-term regular hemodialysis treatment (RDT) at our dialysis unit who underwent diagnostic cerebral computed tomography (CCT) participated in a study aimed at clarifying the pathogenesis of cerebral atrophy occasionally found at their original scan. The upper age limit was 55 years to exclude the physiological involutive brain changes occurring with age. Cerebral atrophy (CA), as defined morphologically (enlargement of cerebral sulci or an increased Evan's Index), was detected in all cases. Seventeen patients underwent magnetic resonance imaging (MRI) to define possible white matter changes more accurately. No significant correlation was found between the degree of atrophy and the following uremia-altered hematoseric parameters: creatinine, hematocrit, cholesterol, triglyceridemia, albumin, PTH, calcium, inorganic phosphate. There was no correlation between degree of atrophy and number of months the patients had been on RDT or time that passed between the finding of a creatinine clearance <30 ml/min and the start of RDT. Very high correlations were found between the degree of CA and predialytic blood pressure values, and between CA and the duration of hypertension (n = 13, r = 0.66, p < 0.013). Thus, hypertension seems to be an early cause of cerebral parenchymal damage in RDT patients, and should be promptly corrected.

Adult↗
PubMed1998

Regional sympathetic activity in pre-hypertensive phase of spontaneously hypertensive rats.

Imbalances in central and peripheral sympathetic nervous system (SNS) activity have been observed in essential and experimental hypertension. This study was carried out in order to evaluate SNS activity in two distinct tissue types of spontaneously hypertensive rats (SHR), compared to Wistar-Kyoto normotensive (WKY) rats, in the pre-hypertensive phase (4-5 weeks of age). Interstitial concentrations of norepinephrine (NE) and other catecholamines were measured by microdialysis in striated muscle, whose tone is controlled by baroreflexes, and in the subcutaneous adipose tissue where sympathetic output mainly controls metabolism. Two groups of SHR and WKY male rats were studied, aged 4-5 weeks, with a mean body weight of 92 and 86 g respectively. Systolic blood pressure (SBP, tail-cuff) values were 113 mm Hg (SD +/- 6.2) in SHR and 108 mm Hg (SD +/- 7.3) in WKY rats (p=0.28,t test). Two microdialysis probes were positioned in the subcutaneous fatty tissue and in the striated muscle of the parascapular region and perfused with Ringers' solution. The dialysate was collected every thirty minutes for 3 hours and analyzed in HPLC-ED to determine the content of NE and other catecholamines. Interstitial levels of NE were higher in SH than in WKY rats in both tissues. Mean NE values from subcutaneous adipose tissue in 4-5 week-old SHR were 1162 +/- 193 pg/ml compared to 496 + 188 pg/ml in WKY rats (p<0.001, t test). Muscle tissue NE levels in SHR were 1241 +/- 337 pg/ml vs. 521 +/- 138 pg/ml in WKY rats (p<0.001, t test). Plasma NE concentrations (279 +/- 61 pg/ml in SHR vs 246 + 69 pg/ml in WKY P = 0.65, t test) were not significantly different between the two strains at this young age. These findings suggest SNS hyperactivity in young SHR, though still normotensive, possibly dissociated from regional components of regulation (baroreceptor control in striated muscle and metabolic control in subcutaneous adipose tissue).

Adipose Tissue↗
PubMed1997

Effects of reduced preload on diastolic filling in essential hypertensive patients with increased left ventricular mass.

Doppler-derived indices of diastolic filling are widely used in the routine evaluation of essential hypertensives. However, these indices are affected by loading conditions and systolic performance. This study aimed at monitoring the transmitral flow pattern and indices of left ventricular systolic function during acute nonpharmacological isolated reduction of preload in essential hypertensives with left ventricular hypertrophy. Nine essential hypertensive patients with left ventricular hypertrophy and nine age- and sex-matched normotensive controls underwent echocardiographic and Doppler evaluation of both systolic function and diastolic filling indices at baseline and during lower body suction at -40 mm Hg. Lower body suction caused a similar decrease in end-diastolic volume index, stroke volume index, and midwall fractional shortening in the normotensives and hypertensives. Circumferential end-systolic stress was unaffected in both groups. Acceleration time of early diastolic filling and isovolumic relaxation time increased in the normotensives but not in the hypertensives. Deceleration time of early diastolic filling increased in both groups. The ratio of peak velocities during early filling and at atrial contraction decreased in the normotensives, whereas it was unchanged in the hypertensives; this was due to the fact that early filling velocity decreased in both groups, whereas peak velocity at atrial contraction decreased only in the hypertensives. We conclude that Doppler-derived diastolic filling indices are not affected by a reduction of preload in essential hypertensives with left ventricular hypertrophy.

Diastole↗
PubMed1997

[The relationship between regional sympathetic activity and the onset of arterial hypertension in spontaneously hypertensive rats].

Several studies on spontaneously hypertensive rats (SHR) have demonstrated increased activity of the sympathetic nervous system (SNS). Using microdialysis, we have observed a greater release of norepinephrine (NE) into the interstitia of striated muscle, than that observed in control Wistar-Kyoto (WKY) rats in the prehypertensive phase. We confirmed these results in the subcutaneous adipose tissue where the sympathetic output controls metabolism. This study was carried out in order to evaluate SNS activity in two district tissue types conducted during both the prehypertensive phase (4-5 weeks of age) and the established hypertensive phase (15-16 weeks of age). Interstitial concentrations of NE were measured by microdialysis in striated muscle and subcutaneous adipose tissue. Two groups of rats were studied. Each group was made up of 8 subjects, SHR and WKY, males of 4-5 weeks of age with a mean body weight of 80 and 75 g respectively. Arterial systolic pressure (tail-cuff) values were 106 mmHg (standard deviation +/-8.2) in SHR and 101 mmHg (standard deviation +/-6.9) in WKY rats (NS). Two microdialysis probes were positioned in the subcutaneous fatty tissue and in the striated muscle of the parascapular region and perfused with Ringers' solution. The dialysate was collected every 30 min for 150 min and analyzed in high-performance liquid chromatography-every day. The content of NE and other catecholamines was determined. The same animals in both groups were reevaluated at 15-16 weeks of age. The mean body weight at this time was 246 g for the SHR and 289 g for the WKY rats. Arterial systolic pressure was 161 mmHg (standard deviation +/-13.3) and 108 mmHg (standard deviation +/-15.6) respectively (p < 0.01, Student's t test). Interstitial levels of NE were higher in SHR than in WKY rats in both tissues examined in the prehypertensive phase and in the established hypertensive phase. Mean NE values from subcutaneous adipose tissue in 4-5 week-old SHR were 1362.1 +/- 181.3 pg/ml compared to 479.0 +/- 162.3 pg/ml in WKY rats (p < 0.001, Student's t test). Muscle tissue NE levels in SHR were 1292.7 +/- 319.1 vs 536.3 +/- 146.7 pg/ml in WKY rats (p < 0.001, Student's t test). Values from the same rats at 15-16 weeks of age were 1405.0 +/- 148.3 pg/ml in SHR compared to 501.6 +/- 131.2 pg/ml in fatty tissue from WKY rats and 1893.7 +/- 214.6 vs 502.0 +/- 118.8 pg/ml in muscle tissue from the respective groups (p < 0.001, Student's t test). Significant differences (p < 0.01, Student's t test) were also observed in mean NE values in striated muscle tissue during the developing phase of hypertension. These findings document SNS hyperactivity in SHR when compared to WKY normotensive controls. This increase in SNS activity was observed in both the prehypertensive phase and in the established hypertensive phase indicating a complete disassociation from regional components of regulation (baroreceptor control and metabolic control), at least in the prehypertensive phase. These results may suggest as alteration in primitive sympathetic central outflow. Higher interstitial NE concentrations in the muscle tissue from SHR during the hypertensive phase compared to levels of young animals that are still normotensive, reveal an interesting pathophysiological aspect for the development of arterial hypertension.

Animals↗
PubMed1995

Progression of cerebral atrophy in patients on regular hemodialysis treatment: long-term follow-up with cerebral computed tomography.

Fifteen patients (10 males, 5 females) on regular hemodialysis treatment (average age 43.6 +/- 4.0 years, average time on dialysis 100.7 +/- 62.8 months) underwent cerebral computed tomography between 1981 and 1984. Ten patients showed mild cerebral atrophy (CA) on the basis of cortical sulci exceeding 3 mm in breadth and an Evans ratio exceeding 0.31, for a total of 14 degrees of CA (mean 0.9 +/- 1). The same 15 patients underwent a second cerebral computed tomography during 1991/92 (101 +/- 23.7 months later). At that time, the patients exhibited a degree of CA of 2.6 +/- 1.4, for a total of 39 degrees with an overall increase of 25 degrees. Since CA is not detected before the age of 55 years in the normal population, we conclude that the CA in this patient group can only be attributed to uremia-related pathology and that it tends to worsen as regular hemodialysis treatment continues. Nevertheless, no evident cognitive, affective, or behavioural changes were verified in these patients. To our knowledge, this is the first presentation of radiologically documented progression of CA in the same patient population over time.

Adult↗
PubMed1993

[The treatment of arterial hypertension in diabetes mellitus. Choices and problems].

Recent studies indicate that arterial hypertension in diabetes mellitus is a paramount pathogenetic step in the evolution and acceleration of diabetic macro- and microangiopathy and in particular in the development of nephropathy and uremia. This paper deals with the clinical problems of antihypertensive treatment in diabetic patients and discusses the antihypertensive repertory with the aim at determining the best drug choice in the individual case. In the light of our present pathophysiologic knowledges of the intrarenal effects of the various classes of antihypertensive drugs the possibility of preventing diabetic nephropathy is discussed.

Antihypertensive Agents↗