PubMed Health⌕ Search

Biomedical subjects

C Bonato

Publications and source records attributed to C Bonato.

At least 37 records · Page 2Linked to original sources
PubMed1993

[Role of gadolinium (Gd-DTPA) in the staging of renal carcinoma using magnetic resonance. Comparative evaluation with computerized tomography and magnetic resonance without contrast media].

The correct staging of renal neoplasms is critical for both prognosis and subsequent treatment planning. This study was aimed at evaluating the accuracy of contrast-enhanced CT, of plain MR and of contrast-enhanced MR in the staging of renal cell carcinomas (RCC). Forty-four consecutive patients with renal masses were evaluated. All of them underwent plain and enhanced CT and 0.5 T plain and Gadolinium-enhanced MR. T1, T2 and Gd-DTPA T1-weighted MR sequences were acquired (500/20; 2000/100). The diagnostic studies were prospectively and separately interpreted by three radiologists. Imaging findings were then correlated with pathologic findings in all cases. The Robson Staging System was used for pathologic classification. The anatomical staging was correctly performed by CT and MR in 36/44 patients (82%) and by Gd-MR in 39/44 (89%). Seven stage-I and 1 stage-IIIC patients were overstaged by enhanced CT and by plain MR (3 patients to stage II and 5 to stage IV A); 5 stage-I patients were over-staged by Gd-MR (4 patients to stage II and 1 to stage IV A). In four cases, in which CT and MR misdiagnosed stage IV A, Gd-MR correctly identified the lack of adjacent organ infiltration. Perinephric spread, venous invasion, metastatic lymphadenopathy and distant metastases were correctly evaluated by the three imaging modalities. Our results suggest that Gd-DTPA could be useful in identifying direct tumor spread to adjacent organs, because of the different enhancement between the cancer and the other tissues.

Adult↗
PubMed1992

Clinical utility of the serum CA 19-9 test for diagnosing pancreatic carcinoma in symptomatic patients: a prospective study.

The diagnostic accuracy of the serum CA 19-9 determination was prospectively evaluated in patients selected for the presence of signs or symptoms highly suggestive for pancreatic cancer. Of 110 patients included in the study, 54 had a final diagnosis of pancreatic adenocarcinoma (49% prevalence). CA 19-9 values were higher than 40 U/ml in 45 patients with pancreatic carcinoma and in 18 of the 56 patients with other final diagnosis (sensitivity, 0.83; specificity, 0.68; positive predictive value [PPV], 0.71; negative predictive value [NPV], 0.81). The serum CA 19-9 determination was not capable of shortening the diagnostic workup of patients with strong clinical suspicion of pancreatic cancer since adequate imaging of the pancreas was required to confirm or exclude the diagnosis. However, values above 120 U/ml were strongly suggestive for pancreatic carcinoma in the overall population (PPV, 0.85) and they were diagnostic (PPV, 1.0) in the anicteric portion. Combined with pancreatic imaging, the CA 19-9 was an excellent confirmatory test; a normal value in a patient with negative imaging ruled out pancreatic carcinoma as the cause of symptoms (NPV, 1.0), whereas a pathological result in the presence of positive or equivocal pancreatic radiology was highly suggestive for the presence of the disease (PPV, 0.93).

Adenocarcinoma↗
PubMed1992

Dose-response effects of oral loxiglumide on postprandial gall-bladder emptying in man.

The effect of two different single oral doses of loxiglumide (CR 1505, CAS 107097-80-3) on gall-bladder emptying induced by a 550-cal standard mixed meal in 6 healthy volunteers was studied. Following placebo, the maximal gall-bladder emptying occurred about 90 min after the meal (minimal residual gall-bladder volume 27.4% of basal volume). Loxiglumide 400 or 800 mg dose-dependently inhibited the physiologica gall-bladder emptying. Loxiglumide plasma levels dose-dependently increased. The inhibition of gall-bladder emptying and the kinetic of loxiglumide plasma levels were temporally related. The results of the present study confirm that oral loxiglumide is a potent orally active cholecystokinin (CCK) antagonist in man and that CCK is the major physiological mediator of gallbladder emptying in response to meal.

Adult↗
PubMed1992

[Accuracy of magnetic resonance (0.5 T) in traumatic lesions of the knee. Controlled 87 cases].

In this study the authors investigated the diagnostic accuracy of Magnetic Resonance (MR) imaging as a method to recognise traumatic disorders of the knee; in particular its capability to identify meniscal and cruciate ligaments tears was examined. The results have been compared with those from arthroscopy and/or surgery, which were considered the gold standard of the study. Eighty-seven consecutive patients with suspected traumatic injury of the knee were prospectively studied. All patients underwent MR examination (0.5 Tesla magnet, gradient echo sequences, slices thickness = 5 mm) and, within 15 days/1 month, arthroscopy or surgery. The high diagnostic accuracy (internal meniscus = 87.5%; external meniscus = 88.5%; anterior cruciate ligament = 93.1%; posterior cruciate ligament = 96.5%) has confirmed the good diagnostic capabilities of MR in assessing traumatic lesions of the knee.

Arthroscopy↗
PubMed1991

Serum DU-PAN-2 in the differential diagnosis of pancreatic cancer: influence of jaundice and liver dysfunction.

The usefulness of serum DU-PAN-2 in diagnosing pancreatic cancer and in distinguishing between this cancer and other benign and malignant diseases, and to assess the role of liver dysfunction in altering the serum levels of this marker were investigated. DU-PAN-2 was measured in the sera of 31 patients with pancreatic cancer, 32 with chronic pancreatitis, 20 with benign and 21 with malignant extra-pancreatic diseases. DU-PAN-2 was found to be above 300 U ml-1 in 21/31 patients with pancreatic cancer (sensitivity 68%). Only 3/32 patients with chronic pancreatitis had abnormal values. A substantial number of patients with both benign and malignant extra-pancreatic diseases had an elevated serum DU-PAN-2 (9/20 and 15/21, respectively). Correlations were found between DU-PAN-2 and (1) total bilirubin, (2) alanine-amino-transferase and (3) alkaline phosphatase. Of the patients with high DU-PAN-2 values, jaundice was found in: 2/3 with chronic pancreatitis, 9/10 with benign and 12/14 with malignant extra-pancreatic diseases. In conclusion, the serum DU-PAN-2 test for pancreatic malignancy is not completely satisfactory, because it is not sensitive enough. While the test for chronic pancreatitis has an acceptable specificity, the assay cannot distinguish between pancreatic cancer and other extra-pancreatic diseases, mainly of the liver and biliary tract. Liver dysfunction as well as jaundice seem to considerable affect the levels of this marker, as reported elsewhere for CA 19-9.

Adult↗
PubMed1990

Effect of loxiglumide on gallbladder contractile response to cerulein and food in humans.

The present study investigated the effect of loxiglumide, a new selective cholecystokinin-receptor antagonist, on the gallbladder contractile responses to caerulein and to food in humans. In 6 healthy men, the gallbladder emptying driven by intravenous infusion of stepwise increasing doses of cerulein (10-80 ng/kg . h) and that induced by a 550-cal standard meal were monitored by ultrasonography. In both sets of experiments, the effect of loxiglumide was tested at various infusional rates against a control infusion of saline. An infusional rate of 2.5 mg/kg . h of loxiglumide abolished the gallbladder response even to maximal doses of cerulein, whereas a rate of 1.0 mg/kg . h counteracted the cholecystokinetic activity of cerulein up to the dose of 20 ng/kg . h. In postprandial experiments, the cholecystokinin antagonist dose-dependently inhibited the physiologic gallbladder contraction. The maximal gallbladder emptying, which always occurred 85 min after the meal, was 71.1% +/- 3.3% of basal volume in control studies, 39.2% +/- 1.8% during infusion of 2.5 mg/kg . h of loxiglumide, and 17.3% +/- 5.9% when 5.0 mg/kg . h were infused. A dose of 7.5 mg/kg . h of loxiglumide was able to prevent any postprandial emptying of the gallbladder. The present study shows that a selective cholecystokinin receptorial blockade competitively antagonizes cerulein-induced gallbladder contraction and dose-dependently inhibits postprandial gallbladder emptying.

Adult↗
PubMed1990

Gastric histology and function tests in Italian patients with dermatitis herpetiformis.

Gastric mucosal histology and function were evaluated in 57 Italian subjects with dermatitis herpetiformis (DH), by means of multiple endoscopic biopsies, gastrin and pepsinogen I (Pg I) serum levels, and parietal cell antibodies (PCA). One hundred and forty-nine patients with nonulcer dyspepsia served as reference population for the prevalence of atrophic gastritis of the body. Seventeen DH patients (30%) and 23 controls (15.4%) showed atrophic gastritis of the body mucosa (p less than 0.05). Nine of the DH patients with atrophic gastritis of the body also had atrophic changes in the antrum. Six patients, all with severe atrophic gastritis, had high gastrin levels and PCA; five of these six also had low Pg I levels. We found an increased prevalence of abnormal indirect function tests among patients with atrophic gastritis is due to the younger age of the patients in our series. Thus, atrophic gastritis can be detected early on a histologic basis, but functional impairment occurs later, as the mucosal damage increases in severity.

Adolescent↗
PubMed1989

Brain cholecystokinin depletion in rats with acute liver failure.

A decrease of both hypothalamic and cortical CCK occurred in the brain of rats killed 8 hours after hepatic artery ligation following portocaval anastomosis. Brain CCK depletion was not reproduced by exogenously provoked hyperammonemia nor by insulin-induced hypoglycemia, thus suggesting a central mechanism for the derangement of the CCKergic system in the course of acute liver failure.

Ammonia↗
PubMed1989

Pancreatic polypeptide response to food and cerulein in patients with total gastrectomy.

In order to investigate the intestinal phase of pancreatic polypeptide (PP) release, the hormonal response to food and cerulein was measured in 19 patients with truncal vagotomy and total gastrectomy (10 with simple esophagojejunal anastomosis and 9 with an additional duodenojejunal anastomosis) and in 7 healthy subjects. After gastrectomy, the early peak of the physiologic biphasic PP response to food was lost but the late predominant phase was unchanged so that the overall postprandial release of the hormone was not significantly lowered. Gastrectomized patients with duodenal bypass had postprandial serum levels only slightly lower than those of patients with preserved duodenal transit of food. Serum PP response to cerulein stimulation was significantly lower in vagotomized patients than in healthy subjects. However, in operated patients as well as in controls, cerulein infusion did induce a rapid increase of plasma PP, followed by persistently elevated levels. The PP response to cerulein was abolished by atropine pretreatment. Our findings indicate that the intestinal phase of meal-stimulated PP response is not dependent on the integrity of vagal pancreatic innervation and that the preservation of the duodenal transit of food after total gastrectomy is not crucial for the maintenance of the enteroinsular axis.

Adult↗
PubMed1988

Serum pepsinogen I elevation in cigarette smokers.

We measured serum pepsinogen I (sPG-I) in 269 patients undergoing upper GI endoscopy and then classified by endoscopic diagnosis, gastric mucosal histology, and smoking habit. Both ulcer-free and duodenal ulcer smokers had significantly higher sPG-I levels than their non-smoking controls. In contrast, sPG-I values were not different in smokers and non-smokers with gastric ulcer. In ulcer-free smokers the overall increase in sPG-I simply reflected the high prevalence of patients with superficial gastritis and elevated sPG-I levels. Conversely, in duodenal ulcer smokers the increase in sPG-I, which was related to the number of cigarettes smoked daily, was not an epiphenomenon of concomitant gastritis. The smoking-induced increase in sPG-I in duodenal ulcer is proposed to reflect an augmented pepsin secretory capacity, which can be of aetiologic significance in the association between cigarette smoking and duodenal ulcer.

Adult↗
PubMed1988

CA 19-9 in serum and pancreatic juice: its role in the differential diagnosis of resectable pancreatic cancer from chronic pancreatitis.

The diagnostic role of serum and pancreatic juice CA 19-9 determination in discriminating surgically resectable pancreatic cancer from chronic pancreatitis was investigated. Only in about one third of cancer patients the serum assay was diagnostic versus subjects with chronic pancreatitis. None of 5 patients with 'early' pancreatic cancer had a diagnostic score [greater than 120 U/ml]. Conversely, the determination of CA 19-9 content in pure pancreatic juice, expressed as Units per microgram of protein, discriminated all the 15 patients with operable tumors, including those with early carcinoma, from subjects with chronic pancreatitis. The CA 19-9 assay of pancreatic juice is proposed as a reliable marker of cancer in those patients in whom the ERCP pattern is not definitive for malignancy.

Adenocarcinoma↗
PubMed1987

Serum CA 19-9 in the postsurgical follow-up of patients with pancreatic cancer.

In the last few years serum CA 19-9 has been shown to be a highly sensitive marker of pancreatic adenocarcinoma. This study assesses the value of serum CA 19-9 assay in the postsurgical follow-up of patients undergoing pancreatic cancer resection. In 14 patients with cancer in the head of the pancreas and abnormal preoperative serum CA 19-9 values (greater than 40 U/ml), a pancreatoduodenectomy was performed. In all patients the CA 19-9 antigen was immunohistochemically demonstrated on the removed tumoral tissue. Postoperative serum CA 19-9 concentrations were serially measured 15 days after surgery and then every other month. Serum CA 19-9 scores returned to the normal range only in 7 (50%) of the resected patients. All patients with a normal postoperative value and none of those with a persistently elevated one survived longer than 7 months. Early postoperative serum CA 19-9 assay was superior to perioperative staging of the tumor as a prognostic index. All of the seven patients with postoperative normal values exhibited a subsequent increase within 16 months. In all cases the elevation of CA 19-9 occurred at least 2 months before ultrasound (US) could detect local recurrences of hepatic metastasis. Our data indicate that a normal early postoperative CA 19-9 score is a relatively favourable prognostic index in patients who undergo radical surgery for pancreatic cancer and that the CA 19-9 test can be used, as an early marker of recurrence, in monitoring these patients.

Adenocarcinoma↗
PubMed1987

Determination of CA 19-9 antigen in serum and pancreatic juice for differential diagnosis of pancreatic adenocarcinoma from chronic pancreatitis.

Serum CA 19-9 levels were measured in 63 patients with ductal pancreatic adenocarcinoma and in 49 patients with chronic pancreatitis. Concentrations were abnormally high (greater than 40 U/ml) in 57 (90%) patients with cancer and only in 5 (10%) patients with chronic pancreatitis. All patients with falsely normal serum values had poorly differentiated carcinomas. Median CA 19-9 concentrations were progressively higher in patients with more advanced cancer. Fifteen of 16 (93%) patients with localized cancer has abnormal serum levels but only 5 (31%) of them had values greater than 120 U/ml, which was the highest score observed in patients with chronic pancreatitis. Pure pancreatic juice was obtained endoscopically from 23 patients with pancreatic cancer and from 20 with chronic pancreatitis. CA 19-9 concentrations in pancreatic juice were significantly higher in patients with cancer than in non-neoplastic patients. All 11 patients with resectable cancer investigated had a ratio of CA 19-9 to secretory protein concentration in pancreatic juice above the range of patients with chronic pancreatitis. We conclude that serum CA 19-9 determination is highly sensitive and specific for the differential diagnosis of pancreatic cancer versus chronic pancreatitis. However, moderately increased values (less than 120 U/ml), as seen in patients with localized pancreatic adenocarcinoma, are not conclusive for malignancy. The measurement of CA 19-9 to total protein ratio in pure pancreatic juice is proposed as an adjunctive, accurate diagnostic marker for early stages of pancreatic adenocarcinoma.

Adenocarcinoma↗
PubMed1986

Guinea pig 33-amino acid gastrin.

Only two 34 amino acid gastrin precursors have previously been purified and sequenced, those of pig and of human. The larger molecular form generally accounts for only about 5% of antral gastrin in most species. This report describes the purification of "big gastrin" from guinea pig (GP) antra. Two hundred grams of antra were defatted with acetone and the acetone cakes were extracted with 0.1M NH4HCO3. The extract was concentrated by adsorption onto and batch elution from QA-52 anion exchange cellulose. Fractionation on a mu Bondapak C18 cartridge resolved 3.6 nmol of the larger peptide from 61 nmol of immunoreactive gastrin in the original extract. Two additional HPLC steps brought the peptide to final purity. GP big gastrin is a 33 amino acid peptide with the following sequence: less than ELGPQVPAHLRTDLSKKQGPWAEEEAAYGWMDF# The GP peptide is different from pig G34 in 6 of the 17 NH2-terminal amino acids as well as in the previously reported deletion of a glutamic acid in the COOH-terminus.

Amino Acid Sequence↗
PubMed1985

Guinea pig "little" gastrin is a hexadecapeptide.

Gastrin heptadecapeptides (gastrins I and II which differ in the presence of sulfate on the tyrosine of the latter) have been purified and sequenced from several mammalian species including pig, dog, cat, sheep, cow, human and, more recently, rat. This report describes the purification of "little" gastrin from guinea pig (GP) antra. GP antra were defatted with acetone and the acetone cakes were extracted with 0.1M NH4HCO3. The extract was concentrated by adsorption to DE53 anion exchange cellulose and the peak eluates were fractionated on a Sephadex G50F column. The peptides were brought to final purity by 3 successive HPLC steps. The GP sequence compared to other species is shown: (formula: see text) Thus GP "little" gastrins I and II are hexadecapeptides due to a deletion of a glutamic acid in the region 6-9 from the N-terminus.

Amino Acid Sequence↗
PubMed1983

Brain cholecystokinin-8 immunoreactivity in rats with experimental liver cirrhosis.

Cholecystokinin-8 like immunoreactivity (CCK-8 IR) was measured in different brain regions of rats with experimental liver cirrhosis. A statistically significant reduction of CCK-8 content was observed in the hypothalamus of cirrhotic rats. No significant modification of brain CCK fractionation pattern was observed in treated animals as compared to controls. The decrease of CCK-8 IR parallels the recently reported hypothalamic depletion of beta endorphin in cirrhotic rats confirming that central neuropeptides are affected by chronic liver failure.

Animals↗