Biomedical subjects

C Catalano

Publications and source records attributed to C Catalano.

At least 163 records · Page 9Linked to original sources

PubMedDate not supplied

The effect of intravenous metformin on glucose metabolism during hyperglycaemia in type 2 diabetes.

A stepped intravenous metformin infusion was used in conjunction with the hyperglycaemic clamp technique to study the dose-response relationship of plasma metformin concentration with hepatic glucose production and peripheral glucose disposal in nine patients with Type 2 diabetes. The study was of double-blind crossover design, using NaCl infusion as control. Plasma metformin concentrations spanning the therapeutic range (1.64 +/- 0.13 mg l-1 and 6.57 +/- 0.61 mg l-1) were achieved. No differences in peripheral glucose disposal were demonstrated when compared with NaCl infusion (3.4 +/- 0.1 vs 3.6 +/- 0.2 (+/- SE) mg kg-1 min-1 and 3.4 +/- 0.2 vs 3.3 +/- 0.2 mg kg-1 min-1, respectively). There was also no difference in basal hepatic glucose production during metformin and NaCl infusion (2.7 +/- 0.3 vs 2.8 +/- 0.2 mg kg-1 min-1). No acute effect of metformin on hepatic glucose production or peripheral glucose disposal was observed, implying that a chronic persistent effect is more important in these respects than immediate effects consequent upon changes in plasma drug level.

Blood Glucose↗

PubMedDate not supplied

[MR imaging of pancreatic neoplasms].

The role of MR imaging in the assessment of pancreatic adenocarcinoma is in identification, characterization and staging of the neoplastic lesion. Technique optimization is required in order to obtain high qualities images competitive with spiral CT. The choice of imaging protocol is strictly related to the available equipment as well as fast imaging capabilities. Contrast-enhanced study using breath-hold sequences is required if working at high field strength with high gradient performance; on mid-low field strength nonbreath-hold acquisition techniques, using respiratory compensation techniques, can be implemented. The use of fat saturation pulses may increase the sensitivity of MR in detecting pancreatic lesions. Other advantages of MR imaging are represented by the availability of additional noninvasive techniques for the evaluation of the biliary tree (MR-cholangiopancreatography) and splanchnic vessels (MR-angiography). Lesion identification is based on TIw sequences where the lesion appears hypointense compared with the surrounding pancreas; increased lesion-pancreas contrast is obtained when fat suppression is used. On dynamic studies following gadolinium injection, pancreatic tumors are hypovascular compared with surrounding normal pancreatic gland. Problems in correctly defining the size of the lesions may be encountered in patients presenting with inflammatory changes of the pancreatic parenchyma surrounding the carcinoma (epineoplastic pancreatitis). For lesion characterization MRI is not able to characterize focal pancreatic lesions, allowing a differential diagnosis between pancreatic cancer and focal hypertrophic chronic pancreatitis. Even the use of MR-cholangiopancreatography is not helpful for characterizing focal pancreatic masses. MR imaging is accurate in local staging (assessment of peripancreatic fat infiltration) thanks to the higher contrast resolution, but in vascular staging and in the evaluation of lymphnodal involvement it suffers the same limitations as computed tomography. Future perspective are represented by the use of magnetic resonance angiography for the evaluation of vascular encasement and the use of specific contrast agents for lymphadenopathy. Identification of hepatic metastases with MRI has been proven to be high, with sensitivity and specificity comparable to CT. The use of liver-specific contrast agents (either positive or negative) is becoming almost routine and it is proving to further improve the diagnostic value of MRI.

Adenocarcinoma↗

PubMedDate not supplied

High resolution computed tomography (HRCT) assessment of beta 2-agonist induced bronchodilation in chronic obstructive pulmonary disease patients.

The evaluation of airway obstruction reversibility in chronic obstructive pulmonary disease (COPD) patients is currently performed by means of an indirect assessment of drug inducing variations in pulmonary function tests. Imaging techniques, especially high resolution computed tomography (HRCT), usually provide a complete evaluation of lung parenchyma (bronchial and vascular structures), but so far they have never been applied to visualize the effects on the bronchopulmonary tree of some pharmacologic stimuli (beta 2 adrenergic agonist), currently used in clinical practice to disclose the presence of airway reversibility. In order to assess the possible role of HRCT in this setting, five COPD patients have been subjected to a double functional radiologic evaluation before and after salbutamol-induced broncho-dilation, with a rigorous assessment of bronchial diameter changes by means of "bronchus-vessel" ratio, currently used for diagnosing bronchiectasis in COPD patients. The results of this experimental study enable us to visualize drug induced broncho-dilation, with a direct assessment of airway reversibility in these patients, and to show a good correlation between functional and HRCT findings, raising the possibility of evaluation COPD patients with abnormal spirometric results or with early signs of lung involvement.

Administration, Inhalation↗

PubMedDate not supplied

Topographic diagnosis and surgical treatment of insulinoma.

AIM: Controversy continues to reign with regard to the need for preoperative localization of insulinomas and to which are the most sensitive and accurate diagnostic imaging modalities. Our aim was to determine the role of diagnostic procedures and suggest which of them are really useful. METHODS: Over a 12-year period 34 patients underwent several preoperative diagnostic procedures to localize the insulinoma: ultrasonography (US) in 20 cases, computed tomography (CT) in 26, magnetic resonance imaging (MRI) in 28, selective angiography in 8, arterial stimulation venous sampling (ASVS) in 23 and Octreoscan in 26. All patients underwent surgical palpation and in 32 cases intraoperative ultrasonography (IOUS) was performed. Twenty-six cases underwent enucleation, six had distal pancreatic resections and two patients had only exploratory laparotomy with liver biopsies. We compared the findings of the diagnostic procedures and analyzed the surgical treatment chosen according to the pancreatic site of the tumor. RESULTS: In 32 (94.1%) of the 34 patients with clinically suspected pancreatic insulinoma the tumor was found at surgery. Preoperative US achieved 5.2% sensitivity, CT 29.1%, selective angiography 28.5% and MRI 76.9%. ASVS achieved 91.3% sensitivity and diagnostic accuracy whereas Octreoscan achieved only 65.3% diagnostic accuracy. Surgical palpation performed before IOUS identified the tumors in 30/34 patients: in the other four cases, one was a false-positive result (a cyst in the pancreatic head), two were true negatives and one was a false negative. Surgical palpation therefore yielded 88.2% diagnostic accuracy. IOUS was performed in 32 cases and localized the tumors in 29/32 cases (sensitivity: 96.6%) with one false-negative result (diagnostic accuracy: 96.8%). The operative mortality was 2.9% and the morbidity 24.6% (30.7% in patients treated by tumor enucleation). CONCLUSIONS: No single diagnostic imaging modality is reliable for localizing insulinoma. We therefore suggest combined MRI, ASVS and IOUS. ASVS provides particularly useful information for planning manual palpation and intraoperative ultrasonography.

Adolescent↗

PubMedDate not supplied

[Magnetic resonance angiography with contrast media in the study of carotid arteries].

PURPOSE: Purpose of our study was to determine the feasibility and accuracy of contrast enhanced Turbo-MRA (CE-MRA) in the evaluation of patients with carotid artery stenosis, using a dynamic technique with multiple acquisitions. MATERIAL AND METHODS: 37 patients with suspected carotid artery stenosis were studied with a 1.5 T magnet (Siemens Vision Plus) using, with a neck phased array coil, a dynamic tridimensional T1 weighted spoiled GRE (TR/TE/NEX: 3.8/1.4/1; Matrix = 110 x 160; FOV = 163 x 260 mm TA = 10 seconds for each sequence); 4 consecutive sequences were performed during the same breath hold, acquired after i.v. bolus injection with a power injector (Spectris, Medrad) of 15 ml of Gd-DTPA followed by 10 ml of saline solution (flow rate 2 ml/s). The beginning of the sequence coincided with the injection of Gd-DTPA. Images were reconstructed using a standard MIP algorithm, by selecting which of the sequences provided the highest enhancement. In all patients a DSA was also performed. Images were separately evaluated using conventional angiography as the gold standard and assessed for degree of stenosis by using NASCET criteria, and morphology of the plaque. RESULTS: CE-MRA correctly evaluated the degree of stenosis in 71 of the 74 patients, while overestimated the remaining 3 cases correctly evaluated by DSA. In 12 cases ulcerations were adequately demonstrated by one of the radiologist, while 11 on 12 were depicted by the other one. CE MRA allowed to detect tandem lesions of the internal carotid arteries (by both radiologists) in 13 of 74 carotids studied. Stenosis at the origin of the common carotid arteries were correctly detected in 9 cases. Sensitivity, specificity and accuracy were respectively of 98, 97 and 99%. DISCUSSION AND CONCLUSIONS: In order to perform an optimal CE-MRA a dynamic technique must be performed to avoid venous filling. The possibility to use ultrafast imaging allows to selectively image the carotid arteries without jugular filling. The well known tendency to overestimate the degree of stenosis has not been found in this group of patients. CE-MRA is a rapid, reliable method to evaluate patients with suspected carotid artery stenosis. These results allow to consider dynamic CE-MRA as a valid method for direct imaging of the carotid arteries.

Carotid Stenosis↗

PubMedDate not supplied

[Thoracic lymphadenopathy due to vascular transformation of lymph node sinuses associated with upper limb edema in a chronic hemodialysis patient with congestive heart failure].

BACKGROUND: Vascular transformation of lymph node sinuses (VTLS) is a rare disorder characterized by transformation of lymph node sinuses into endothelium-lined capillary-like channels. This phenomenon was originally discovered by accident whilst examining regional lymph nodes draining cancer. However, it has been found in association with other conditions associated with lympho venous congestion and distension, such as congestive heart failure (CHF) or even lymphoadenopathy alone. CASE REPORT: We describe the clinical case of a male dialysis patient with CHF (secondary to ischemic-hypertensive cardiac failure) who developed gross edema of the upper left limb on the arteriovenous fistula (AVF) side. Edema appeared within a month after carotid endoarteriectomy following approximately twenty years of chronic hemodialysis. Doppler ultrasound with other investigations showed that subclavian and upper cava veins were patent, but revealed many enlarged lymph nodes in the upper left thorax and in the left axilla. Suspicion of lymphoproliferative disease or metastatic involvement was raised and a lymph node biopsy was performed, revealing VTLS. Bone marrow biopsy and abdominal tomographies showed no mass or a proliferative disorder. Based on a hypothesis of an association between upper limb edema and ipsilateral AVF, the AVF was tied. The upper limb edema decreased dramatically within weeks, whilst RRT was continued by means of a central venous catheter. However, a few months later the patient's condition worsened; he developed relapsing pleural effusions and eventually died. Post-mortem examination revealed severe ischemic-calcific cardiopathy and showed that major thoracic and brachial vessels were patent whilst most thoracic and hilar lymph nodes showed VTLS and fibrosis. CONCLUSIONS: We believe that in our patient CHF was the primary cause of thoracic adenomegaly and that CHF, together with venous hypertension at the left fistula's arm, caused ipsilateral limb edema. Thus, adenomegaly due to VTLS could represent an accompanying feature even in upper limb edema in chronic hemodialysis patients. To our knowledge, this is the first report of such an association. In our patient months were "lost" because we thought that limb edema was secondary to the adenomegaly. It is important that clinicians working in dialysis units are aware that when upper limb edema is present, adenomegaly might just be an accompanying symptom, especially in case of concomitant diagnosis of CHF.

Aged↗

PubMedDate not supplied

[Physiopathology of pre-eclampsia].

BACKGROUND: Pre-eclampsia is a pregnancy-specific disorder that presents major health problems for both mothers and babies. It is a major cause of maternal mortality, especially in developing countries, where it may account for 80% of maternal deaths. In this review we have discussed the putative pathogenetic mechanisms of this severe illness. METHODS: Review of the international literature on pre-eclampsia. RESULTS: Pre-eclampsia occurs predominantly in primigravidas and is associated with increased foetal and maternal risk. Generally speaking, one could hypothesise that during pre-eclampsia the oxidative, coagulative and vasomotor balance is altered by increased sensitivity to angiotensin II associated with reduced synthesis of vasodilator prostaglandins, sympathetic nervous system hyperactivity, hyperlipidaemia associated with raised lipoperoxide synthesis and incomplete implant of cytotrophoblast in maternal spiral arteries. General vasoconstriction could then be a consequence with related utero-placental ischaemia and endothelial damage. These features are clinically characterised by arterial hypertension, proteinuria and sodium retention. The predisposition to develop pre-eclampsia seems to be at least partially hereditary and the risk seems to be transmissible through male sons. To explain the susceptibility of some women to develop pre-eclampsia, specific genetic polymorphisms have been associated to increased risk. CONCLUSIONS: Many factors are involved in the pathogenesis of pre-eclampsia. Occasionally these factors seem to act together, sometimes they do not and, consequently, it might be difficult to postulate a common pathogenesis for the disorder. Good obstetrical practice will identify known risk factors but will not enable physicians to determine the risk value for a particular pregnancy. Moreover, we are far from understanding the exact mechanisms involved, let alone acting upon them. The achievement of these objectives constitute a remarkable challenge for research.

Blood Coagulation↗

PubMedDate not supplied

[Membranous glomerulonephritis and transitional cell carcinoma, improved proteinuria after each tumor resection].

Nephrotic syndrome has been described in association with solid tumours, such as carcinoma of the lung or colon, whilst the relationship between urinary tract cancers and proteinuria is reported less frequently. We describe a case of a 75-year-old man with nephrotic syndrome and relapsing transitional cell carcinoma affecting the bladder. Renal biopsy showed membranous nephropathy. The patient underwent four transurethral tumour resections and each time we observed improved proteinuria by 3-4 weeks after surgery. On the contrary, steroid treatment was clearly unrelated to this improvement. We conclude that, at least in this case, surgical treatment of the tumour led to improved proteinuria whilst steroid treatment was not beneficial.

Aged↗

PubMedDate not supplied

Evaluation of effectiveness of a computer system (CAD) in the identification of lung nodules with low-dose MSCT: scanning technique and preliminary results.

PURPOSE: Evaluation of the effectiveness of computer-aided diagnosis (CAD) in the identification of pulmonary nodules. MATERIALS AND METHODS: Two observers (A1, A2) with different levels of experience independently evaluated 20 chest MSCT studies with and without the aid of a CAD system (LungCheck, R2 Technology, Inc). The study parameters were as follows: 140 kVs, 40 mAs, collimation 4 x 1 mm, slice thickness 1.25 mm, reconstruction interval 1.0 mm. The observers analysed the images with and without CAD and evaluated: 1) nodule size (longer axis); 2) number and location of nodules; 3) reading time for each observer. The gold standard was represented by the evaluation of both readers in consensus with the aid of the CAD system. RESULTS: Without CAD support the two readers identified 77 (A1) and 79 (A2) nodules and with CAD 81 (A1) and 82 (A2) nodules. Working in consensus the two observers identified 81 nodules without the aid of the CAD and 84 nodules with the aid of CAD. Total number of nodules identified by CAD was 104, 25 of which were false positive and 5 false negative. The average reading time with the aid of the CAD decreased by as much as 40% for both the observers. CONCLUSIONS: The preliminary results of our study suggest that the CAD technique is an accurate automatic support tool in the identification of pulmonary nodules. It reduces reading time and automatically supplies the size, volume, density and number of nodules, thus being useful both in screening programmes and in the follow-up of cancer patients, in whom comparison of the images is particularly difficult.

Adult↗

PubMedDate not supplied

[Valaciclovir-related neuro- and nephro-toxicity in two geriatric patients].

BACKGROUND: Valaciclovir (VAL) is the L-valyl ester of acyclovir and it is quickly hydrolysed to acyclovir. Acyclovir-related nephrotoxicity is associated with high drug infusion doses and VAL-related neurotoxicity to pre-existing renal failure. We observed two geriatric patients with normal serum creatinine who developed acute renal failure (ARF) and neurotoxicity after ingesting the drug at the conventional therapeutic dose. CASE REPORTS: The first patient was a 77-year-old female admitted to the intensive care unit because of anuria associated with coma and respiratory insufficiency. Baseline serum creatinine (Scr) was 0.9 mg/dL. Four days previously she had started VAL 1 g/bd for cutaneous HZ. Scr was 7 mg/dL and urinary output was <100 cc/24 h. The patient was ventilated and hemodialysis (HD) was started. After 6 days her urinary output increased and dialysis was discontinued. Two weeks after admission, Scr was 1.5 mg/dL, ventilation was discontinued and her consciousness level was normal. The second patient was a 73-year-old male. Baseline Scr was 0.7 mg/dL. He started VAL 1 g/TD because of hepatic cheratitis. After 4 days, he developed oliguria and stupor. At admission, Scr was 5.5 mg/dL, potassium was 6 mEq/L and the patient was unconscious. After drug withdrawal the diuresis increased and his consciousness level returned to normal. After 7 days Scr was 0.9 mg/dL. COMMENT: The clinical evolution suggested that the syndrome was related to the antiviral therapy. ARF preceded neurotoxicity. We suggest that high bioavailability, reduced glomerular filtration rate (GFR) related to age, and possibly the simultaneous ingestion of other drugs could have caused these side effects. We recommend the emphasis on potential side effects of antiviral therapy when treating geriatric patients even if Scr is in the normal range.

Acyclovir↗

PubMedDate not supplied

Noninvasive assessment of coronary artery stenoses by multidetector-row spiral computed tomography: comparison with conventional angiography.

BACKGROUND: Coronary artery disease (CAD) is the most common cause of hospitalization and mortality in many industrialized countries. We analysed the diagnostic accuracy of multi-detector row spiral computed tomography (MDCT) in determining mid- to high-grade coronary artery stenoses (> 50%). METHODS: Sixty-nine patients with suspected CAD were referred to MDCT coronary angiography. Patients with a heart rate above 60 bpm received 20-40 mg propranol before the scan. The left main (LM), the left anterior descending artery (LAD), the first diagonal branch (D1), the right coronary artery (RCA) and the proximal tract of the circumflex artery (LCX) were independently evaluated by two blinded observers and screened for > 50% stenoses. The mean values of MDCT coronary narrowings assessed by two observers were compared to quantitative coronary angiography. RESULTS: MDCT correctly detected 95 of 123 coronary lesions (sensitivity 77.2%) and absence of stenoses was correctly identified in 388 of 426 segments (specificity 91%). The sensitivity for the LM, LAD, RCA and the proximal tract of LCX was 100%, 86.5%, 69.8% and 80% respectively. Classification of patients as having 1-vessel, 2-vessels, 3-vessels or left main disease was accurate in 75.4% (46/61) of patients. CONCLUSIONS: MDCT technology, combined with heart rate control, allows reliable noninvasive detection of hemodynamically significant CAD.

Coronary Angiography↗

PubMedDate not supplied

[Prevalence of insulin-dependent and non-insulin-dependent diabetes among Italian patients on replacement therapy. Preliminary survey at 3 dialysis centers].

We carried out a retrospective survey to assess prevalence and type of diabetes in three Italian Renal Units located respectively in the North (Tradate, Varese), in the Middle (Latina) and in the South (Reggio Calabria) of Italy. The prevalence of diabetes among patients accepted for RRT was 10.5% (60/659). 40 patients (66.7%) were non-insulin dependent and only 6 patients were insulin-dependent. A similar pattern was observed among the 289 patients referred to the Renal Unit of Reggio Calabria during 1972-1987 for evaluation of Chronic Renal Failure. Our data suggest that among the Italian diabetic patients treated by dialysis and transplantation insulin-dependent diabetes is uncommon. This finding could be explained by the low incidence of insulin-dependent diabetes in Italy.

Adult↗

PubMedDate not supplied

[Cebocephaly: a severe cerebro-craniofacial malformation. Description of a case].

The paper reports the case of a newborn affected by malformations of the middle parts of the face. The patient was described as cebophalus according to Kundrat's classification because he had a single nostril, hypotelorism and severe brain malformations. Prosencephalia is present in 0.5% of all aborted fetuses but is very rare in live births (0.006%). Survival is extremely short and in this case the patient lived for 12 months. A description of the malformations is given using CT scans.

Abnormalities, Multiple↗

PubMedDate not supplied