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C Catalano

Publications and source records attributed to C Catalano.

At least 55 records · Page 3Linked to original sources
PubMed1999

MRI of the biliary and pancreatic ducts.

Magnetic resonance Cholangiopancreatography (MRCP) is a non-invasive imaging technique able to provide projectional images of the bile ducts. Different sequences, using both breath-hold and non-breath-hold acquisition techniques, have been employed in order to obtain MRCP images. The authors discuss technical aspects, considering both three-dimensional non-breath-hold techniques and two-dimensional breath-hold, multi-slice and thick slab sequences. Clinical applications of MRCP are evaluated, presenting data from both the literature and personal experience. The main indication for MRCP study is represented by the evaluation of common bile duct obstruction, with the aim of assessing the presence of the obstruction (accuracy 85-100%) and, subsequently, its level (accuracy 91-100%) and its cause. The utility of associating conventional MR images to MRCP in malignant strictures, in order to characterize and stage the malignant lesion, is also discussed. Finally, data are presented regarding the indications and the utility of MR-pancreatography in the evaluation of patients with pancreatic duct anomalies and chronic pancreatitis.

Bile Duct Diseases↗
PubMed1999

Light regulation of assimilatory sulphate reduction in Arabidopsis thaliana.

Adenosine 5'-phosphosulphate reductase (APR) is considered to be a key enzyme of sulphate assimilation in higher plants. We analysed the diurnal fluctuations of total APR activity and protein accumulation together with the mRNA levels of three APR isoforms of Arabidopsis thaliana. The APR activity reached maximum values 4 h after light onset in both shoots and roots; the minimum activity was detected at the beginning of the night. During prolonged light, the activity remained stable and low in shoots, but followed the normal rhythm in roots. On the other hand, the activity decreased rapidly to undetectable levels within 24 h of prolonged darkness both in shoots and roots. Subsequent re-illumination restored the activity to 50% in shoots and to 20% in roots within 8 h. The mRNA levels of all three APR isoforms showed a diurnal rhythm, with a maximum at 2 h after light onset. The variation of APR2 mRNA was more prominent compared to APR1 and APR3. 35SO42- feeding experiments showed that the incorporation of 35S into reduced sulphur compounds in vivo was significantly higher in light than in the dark. A strong increase of mRNA and protein accumulation as well as enzyme activity during the last 4 h of the dark period was observed, implying that light was not the only factor involved in APR regulation. Indeed, addition of 0.5% sucrose to the nutrient solution after 38 h of darkness led to a sevenfold increase of root APR activity over 6 h. We therefore conclude that changes in sugar concentrations are also involved in APR regulation.

Arabidopsis↗
PubMed1999

MR cholangiography of late biliary complications after liver transplantation.

OBJECTIVE: The aim of our study was to assess the role of MR cholangiography in the diagnosis of late biliary complications after liver transplantation. SUBJECTS AND METHODS: Twenty-three liver transplantation patients (18 men and five women; mean age, 46 years) underwent MR cholangiography using a nonbreath-hold, fat-suppressed three-dimensional turbo spin-echo sequence (TR/TE, 3000/700; echo train length, 128) optimized on a 0.5-T magnet. Inclusion criteria were liver function tests with abnormal results and hyperbilirubinemia with a clinical pattern not specific for biliary obstruction. All patients were referred by clinicians for contrast-enhanced cholangiography. Diagnostic confirmation was obtained with percutaneous transhepatic cholangiography (n = 4), endoscopic retrograde cholangiography (n = 8), T-tube cholangiography (n = 1), or clinical follow-up (n = 10). RESULTS: In 11 patients, no abnormalities of the biliary tract were revealed by MR cholangiography. In 11 patients, twelve strictures were diagnosed (nine anastomotic, two nonanastomotic-intrahepatic, and one nonanastomotic-extrahepatic, with association between anastomotic and nonanastomotic strictures in two cases). In one other patient, kinking of the common bile duct at the level of the anastomosis was observed. In all cases, MR cholangiography correctly showed the site of the stricture and the dilatation of bile ducts above, with excellent correlation with contrast-enhanced cholangiographic findings. Strictures were correctly graded in eight of 10 patients and were overestimated in two. Other findings included a 1-cm stone detected proximal to the obstructed common bile duct in one patient and multiple intrahepatic stones in another patient. CONCLUSION: MR cholangiography can show biliary obstruction and provide important information for planning therapeutic procedures.

Adult↗
PubMed1999

Localization of pancreatic insulinomas with MR imaging at 0.5 T.

OBJECTIVE: To determine the role of MR imaging in the localization of pancreatic insulinomas in patients with clinical and laboratory diagnosis of insulin-producing tumor. MATERIAL AND METHODS: Thirty-one patients presenting with signs and symptoms of pancreatic insulinomas were prospectively included in our study. Twenty-six patients underwent surgery, and pathologic specimens were examined: 5 patients, in whom the initial diagnosis of insulinoma was excluded, were also studied and then followed up. All patients were studied with a high gradient power 0.5 T magnet. Images were evaluated by 2 radiologists blinded to previous investigations, tests and results. RESULTS: MR imaging correctly localized 24 of the 26 insulinomas (2 were false-negative and 1 false-positive) and was correctly negative in the 5 control patients. The interobserver agreement had a kappa value of 0.89. CONCLUSION: MR imaging was accurate in localizing pancreatic insulinomas and as a consequence, patients in our institution are now submitted to surgery directly after the MR examination. Invasive methods are considered only in cases in which, despite clear biochemical results, MR imaging has not demonstrated a pancreatic focal lesion.

Adolescent↗
PubMed1999

MR pyelography and conventional MR imaging in urinary tract obstruction.

PURPOSE: To evaluate the possible role of MR imaging in the assessment of patients with urinary tract obstruction by combining conventional MR imaging and MR pyelography (MRP). MATERIAL AND METHODS: Forty-three patients with dilated upper urinary tract were studied with a high gradient strength 0.5 T magnet. Respiratory compensated T1-weighted, SE and T2-weighted TSE sequences were acquired in all patients. MRP images were obtained by using a respiratory compensated 3D T2-weighted TSE sequence. MRP images were reconstructed with a MIP algorithm. In all cases, urography and/or ascending pyelography were also performed. Images were independently evaluated by two radiologists. RESULTS: The dilated tract ureter and the level of the obstruction could be correctly demonstrated in all cases. The cause of the obstruction was correctly demonstrated by examiner 1 in 90% and by examiner 2 in 88%. The interobserver agreement was high with a kappa-value of 0.96. CONCLUSION: In cases of obstructive hydroureteronephrosis MR imaging, combining MRP and conventional sequences, can be proposed as an accurate technique in the assessment of level and cause of obstruction.

Aged↗
PubMed1999

Biochemical studies on a novel antioxidant from lemon oil and its biotechnological application in cosmetic dermatology.

It is generally accepted that lipid peroxides play an important role in the pathogenesis of free radical-induced cellular injury and that antioxidants such as glutathione, ascorbic acid and alpha-tocopherol are vital in cellular defense against endogenous and exogenous oxidants. The purpose of this study was to investigate the effectiveness of a natural compound, derived from lemon oil extract, in controlling free radical-induced lipid peroxidation and tissue damage in the skin. We provide evidence that a compound isolated from lemon oil, which we have called Lem1, is endowed with a strong antioxidant activity and that it is capable of inhibiting free radical-mediated reactions, evaluated by both in vitro and in vivo biochemical systems. The present study aims to give a preclinical perspective on the biochemical properties of Lem1, a natural compound, as well as to provide a better understanding of the endogenous antioxidant potential of skin and the real validity of a natural antioxidant biotechnology in the antiaging management of the skin.

Adolescent↗
PubMed1999

[Magnetic resonance imaging and magnetic resonance cholangiopancreatography in evaluation of chronic pancreatitis. Part I: techniques and methods].

Until recently, MR examinations of the pancreas were limited by motion artifacts, vascular pulsatility and poor spatial resolution. Today, new techniques have been developed, which allow to overcome these problems and provide additional information such as selective images of biliary and pancreatic ducts and vascular structures. MR examinations of the pancreas need to include either breath-hold or nonbreath-hold morphological T1- and T2-weighted images; a contrast agent is required when the study is performed with fast imaging which allow the acquisition of dynamic images in arterial and portal venous phases. Recently, a new liver-specific contrast agent (Mn-DPDP) has been demonstrated to provide selective pancreatic enhancement. As a complement to baseline sequences, MR cholangiopancreatography images can be acquired, possibly integrated by functional examination after secretin administration. Finally, contrast-enhanced MR angiography opens new perspectives for vascular studies, particularly for the locoregional staging of pancreatic cancer.

Cholangiography↗
PubMed1999

Oxidative stress and antioxidants at skin biosurface: a novel antioxidant from lemon oil capable of inhibiting oxidative damage to the skin.

Atmospheric pollutants are an important source of oxidative and nitrosative stress both to terrestrial plants and to animals. Skin, which has a highly differentiated and certainly complex organizational structure, is particularly vulnerable to free radical damage because of its contact with oxygen and with other environmental stimuli. Fruit and vegetables contain several classes of compounds that when ingested can potentially contribute to antioxidant defenses. In the present study we employed a novel gas chromatographic method to assess the antioxidant properties of a natural compound isolated from lemon oil, which we have called Lem1. We provide experimental evidence that Lem1 is endowed with a strong antioxidant activity and that it is capable of inhibiting free radical-mediated reactions, as evaluated in vitro and in vivo. The present study extends our previous findings and demonstrates that topical application of Lem1 in healthy volunteers significantly increases the antioxidative potential of skin biosurface, thus highlighting the effectiveness of a natural antioxidant biotechnology in the antiaging management of skin.

Administration, Topical↗
PubMed1998

Pancreatic adenocarcinoma: combination of MR imaging, MR angiography and MR cholangiopancreatography for the diagnosis and assessment of resectability.

The purpose of this study was to determine the possibility of integrating MR cholangiopancreatography (MRCP) and MR angiography (MRA) to conventional MR images in the diagnosis and assessment of resectability of pancreatic adenocarcinoma. Twenty-three patients with pancreatic adenocarcinoma were prospectively examined with MR. Conventional MR images were acquired in all patients. Three-dimensional MRCP and MRA images were acquired in all patients with suspected biliary and vascular involvement. Acquisition time was less than 45 min in all cases. Images were independently evaluated by two radiologists, with final reading decided by consensus among readers. Diagnosis was confirmed with surgery in 16 patients and with percutaneous biopsy in 7. Concordance among readers was high with a kappa value of 0.83. Pancreatic adenocarcinoma was observed in all patients. Correct assessment of unresectability due to vascular involvement was found in 22 of 23 patients. Biliary obstruction was evident in 13 patients, involving the biliary and pancreatic ducts in 9 and the biliary ducts only in 4. Technical advances permit extensive use of MRI in the evaluation of abdominal pathologies. The combination of MR imaging, MRCP, and MRA can provide sufficient information for the diagnosis and assessment of resectability of pancreatic adenocarcinoma, which otherwise would require three different exams.

Adenocarcinoma↗
PubMed1998

MR cholangiography: techniques and clinical applications.

Magnetic resonance cholangiography (MRCP) is a new non-invasive imaging technique for the evaluation of bilio-pancreatic disorders. Different sequences, using both breathhold and non-breathhold techniques, have been employed in order to obtain MRCP images. The authors discuss the technical aspects, particularly focusing their attention on a non-breathhold, three-dimensional, fat-suppressed turbo-spin-echo sequence, optimized on a 0.5-T magnet with 15 mT/m gradients. Clinical applications of MRCP are evaluated, presenting data from both the literature and personal experience. The main indication for MRCP study is represented by the evaluation of common bile duct obstruction, with the aim of assessing the presence of the obstruction (accuracy 85-100 %) and, subsequently, its level (accuracy 91-100 %) and its cause. The utility of associating conventional MR images to MRCP in malignant strictures in order to characterize and stage the malignant lesions is also discussed. Finally, data are presented regarding the indications and utility of MR pancreatography in the evaluation of patients with chronic pancreatitis.

Biliary Tract↗
PubMed1998

Reinfusion and concentration of ascitic fluid during hemodialysis in a cirrhotic uremic patient.

Management of tense ascites in cirrhotic patients on chronic hemodialysis is still a matter of speculation. A considerable problem with these patients is the frequent occurrence of hypotension during ultrafiltration. We describe a patient in whom ascitic fluid was reinfused on the arterial line and ultrafiltrated during standard treatment by using a single dialysis monitor, standard dialysis (SD) lines, and a standard hollow-fiber dialyzer. After 30 to 60 minutes of dialysis, with the patient lying on his left side, a gauge #16 IV catheter was introduced into the left lower abdomen and connected to the reinfusion line. The ascitic fluid was pumped from the abdomen to the arterious inlet of the coil at 500 to 2,000 mL/hr and ultrafiltered. In an individual patient, 13 sessions of ascites reinfusion-ultrafiltration dialysis (ARD) were performed over 3 months and compared with 18 SD sessions performed during the same period. In all procedures, the same SD equipment was used. During ARD, the average weight loss was 2.9 (SD 1.0) kg compared with a weight loss of 0.3 (0.04) kg during SD (P < 0.01). Baseline mean blood pressure was similar in both procedures; after starting dialysis, mean arterial pressure (MAP) dropped by an average of 15 mm Hg at 30 and 60 minutes. Subsequently, during ARD, MAP increased progressively by an average of 20 mm Hg at 180 minutes, whereas MAP did not change significantly during SD. Comparison between procedures by nonparametric one-way analysis of variance showed that body weight became significantly different at 120, 150, and 180 minutes (P < 0.01) and MAP at 150 and 180 minutes (P < 0.02 and P < 0.01, respectively). No major complications occurred. During ARD, on average urea reduction rate was 67%. ARD may represent an effective and safe combination between hemodialysis and the palliative treatment of tense ascites in cirrhotic uremic patients.

Aged↗
PubMed1998

Short-term outcome of diabetic patients in renal replacement therapy.

BACKGROUND: Diabetic nephropathy or diabetes-related nephropathies represents one of the most relevant causes of renal failure in recent years. This complex pathological picture becomes particularly severe as time elapses and after starting renal replacement therapy (RRT). METHODS: In an attempt to investigate the evolution of the major clinical features, a retrospective study was carried out on a cohort of 76 diabetic patients on RRT. Sixty-five have been treated by haemodialysis (HD) and 11 by peritoneal dialysis (CAPD), for at least 1 year. In these patients change in modality of treatment, metabolic control, cardiovascular, and ophthalmological complications, peripheral neuropathy, state of vascular access, and intradialytic complications were surveyed at initiation and after 1 year of treatment. A modified Karnofski's score was utilized, to evaluate the degree of rehabilitation. The comparison of prevalence was evaluated, using Student's t-test for paired samples. RESULTS: After 1 year, 11 patients on CAPD remained on the same type of treatment. Out of 65 patients on standard bicarbonate HD, 11 were moved to acetate free biofiltration, two to paired filtration dialysis and one to haemofiltration. A worsening in arrhythmias was recorded with an increased prevalence from 25.0 to 35.0% (n.s.), and one more patient (15 vs 16 and 19 vs 20 respectively) experienced ischaemic cardiomyopathy and cerebrovascular insufficiency. Hypertension showed a significant improvement (72 vs 42, P<0.01). Nausea and vomiting, hypotensive episodes, and muscular cramps were more frequently observed. A worsening in patient's welfare was also recorded but without statistical significance. CONCLUSIONS: This clinical evaluation even if retrospective and lasting 1 year, may suggest that RRT does not per se represent a cause of the development and progression of the major complications related to diabetic disease.

Adult↗
PubMed1998

The effect of metabolic control on development and progression of diabetic nephropathy.

The progressively growing number of patients with end-stage renal failure (ESRF) associated with diabetes mellitus and requiring renal replacement therapy (RRT) stimulated both nephrologists and diabetologists to investigate the mechanisms linking hyperglycaemia to diabetic renal failure and to set up measures to prevent the onset and slow the progression of diabetic nephropathy. Over the last few decades, a large number of studies have investigated both the incidence of diabetic nephropathy and the relationship between metabolic control and the development of diabetic nephropathy. Chronologically, the first type of diabetes and diabetic nephropathy to be studied was type I, and it is only in recent years that metabolic control has been proven to be a contributor to the development of nephropathy in such patients. Recently, the DCCT demonstrated that metabolic control in the prealbuminuric phase was effective in reducing the incidence of microalbuminuria, even if it was unable to reduce the incidence of overt proteinuria in patients with type I diabetes and established proteinuria. On the other hand, in type II diabetes, the number of studies demonstrating a favourable effect of metabolic control on onset and progression of diabetic nephropathy is only slightly greater than those that failed to show a favourable effect. This feature may suggest that in type II patients, genetic and ethnic differences, nutritional aspects, lifestyle and other confounding factors may play a relevant role in the course of the disease. However, the trials performed and the retrospective analyses generally agree that glycated haemoglobin two standard deviations greater than the mean is related to a worsening in progression of diabetic nephropathy and to an enhanced risk of other complications. In general, a glycated haemoglobin < or =8% seems advisable. Moreover, in both type I and type II, greater emphasis should be placed on the major risk factors such as hypertension, smoking habits and hyperlipidaemia.

Diabetes Mellitus↗