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Biomedical subjects

A Pietrabissa

Publications and source records attributed to A Pietrabissa.

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

Nonoperative management of pancreatic pseudocysts. Problems in differential diagnosis.

CONCLUSION: The evaluation of pancreatic cystic lesions entails a misdiagnosis risk. Awareness of the problem, knowledge of the natural history of these lesions, and meticulous posttreatment follow-up can reduce the consequences of diagnostic errors. If all these precautions are adopted, pancreatic pseudocysts can be safely treated nonoperatively. BACKGROUND: The accurate diagnosis of pancreatic cystic lesions remains a problem. The aim of this study was to ascertain the incidence of and the reasons the diagnostic errors occurred in a series of pseudocysts drained percutaneously and to compare these data to those reported in the literature. METHODS: Data from 70 patients bearing one or more pseudocysts who underwent a percutaneous drainage were reviewed. The pretreatment workup included medical history, physical examination, ultrasound (US) and computed tomography (CT) scans, amylase assay in both the serum and the cystic fluid, culture and cytology of the cystic fluid. After removal of the drainage, the minimum follow-up period was 12 mo. RESULTS: Four patients died, and two cancer-associated pseudocysts were identified before removal of the drainage. Sixty-four patients were followed up for a mean of 51.9 mo (range 12-154 mo). A third cancer and a mucinous cystic tumor, fully communicating with the main duct, were further detected during this period.

Adult↗
PubMed1999

Laparoscopic Nissen fundoplication complicated by late gastroesophageal herniation and intrathoracic perforation: a case report with review of the literature.

We report the case of a 38-year-old man who, 2 weeks after a laparoscopic Nissen fundoplication, was referred to our Unit because of acute wrap herniation and intrathoracic gastric perforation. Although both of these complications have already been described, this is the first case in which they have occurred simultaneously and not as an immediate consequence of the operation. Intraoperative findings suggested that diaphragmatic crura had not been reapproximated and that the gastric wrap had not been fixed to them. This observation and the fact that immediately after hospital discharge the patient had sustained intense physical efforts can explain acute wrap herniation. Placement of full-thickness sutures may account for gastric perforation. These pathogenetic determinants and their preventive measures are discussed in the light of a review of the literature.

Adult↗
PubMed1998

Catechol-O-methyltransferase: variation in enzyme activity and inhibition by entacapone and tolcapone.

OBJECTIVE: The aim of this investigation was to study the variation of catechol-O-methyltransferase (COMT) activity in the human liver, duodenal mucosa and renal cortex, and to investigate the inhibition of COMT by entacapone and tolcapone. This study included 87 samples of human liver, 94 samples of the duodenum and 72 samples of the renal cortex. RESULTS: The activity of COMT was measured with 3,4-dihydroxybenzoic acid (242 micromol x l(-1)), the methyl acceptor substrate, and adenosyl-L-methionine (44 micromol x l(-1)), the methyl donor substrate. The hepatic activity of COMT activity was significantly higher in men than in women, whereas it was not sex-dependent in the duodenum or renal cortex. The activity of COMT varied 4.4-fold in the liver of men, 2.6-fold in the duodenum and 5.3-fold in the renal cortex. The median estimates of COMT activity were 577, 499, 103 and 159 pmol x min(-1) x mg(-1) in the liver of men and women, in the duodenum and in the renal cortex, respectively. CONCLUSION: Entacapone and tolcapone were powerful inhibitors of COMT and their IC50 estimates were 151 and 773 nM (P = 0.008), respectively, in the liver; consistent results were obtained with the other tissues.

Adult↗
PubMed1998

Operative technique for thoracoscopic transmyocardial laser revascularization.

We describe herein the operative steps used to perform a transmyocardial laser revascularization by thoracoscopy. A special technique and specific equipment are required for the efficacy and safety of the procedure. Our preliminary results with this novel approach suggest that it could be a valid alternative to the thoracotomic procedure.

Coronary Disease↗
PubMed1998

Transmyocardial holmium laser revascularization: feasibility of a thoracoscopic approach.

OBJECTIVE: Creation of transmyocardial channels from the epicardium to the left ventricular cavity with the use of a laser is a modern approach in the treatment of patients with chronic ischemic heart disease unsuitable for coronary angioplasty or bypass grafting. We present the results of transmyocardial laser revascularization (TMLR) with a holmium laser as sole therapy in 22 patients operated on between November 1995 and February 1997. METHODS: There were five females (23%) and 17 males (77%), with a mean age of 67+/-7 years (range 53-74 years). Previous myocardial revascularization had been performed in 77% of the patients. Pre-operatively, 12 patients (55%) were in angina class III and ten (45%) in class IV (mean 3.5+/-0.5); unstable angina was present in seven patients (32%). In 20 patients, TMLR was performed through a limited thoracotomy, while in two a thoracoscopic approach was used. Each patient received a mean of 33+/-8 channels in 27+/-13 min, while total operation lasted 130+/-28 min. RESULTS: There were no hospital deaths and no major post-operative complications. Mean hospital stay was 7+/-3 days; the two patients undergoing thoracoscopic TMLR were discharged after 4 and 5 days, respectively. Two deaths were observed after 40 days and 4 months after TMLR, due to stroke and myocardial infarction. Mean follow-up of current survivors is 10+/-6 months (range 3-15 months), with seven patients followed for over 12 months. At last follow-up, mean angina class is 1.9+/-0.6 (P < 0.001). A significant increase in exercise tolerance and a reduction of the number of hospitalizations for angina were also observed. However, no significant changes in myocardial perfusion were observed. CONCLUSIONS: The present study demonstrates that: (1) TMLR with a holmium laser yields clinical improvement in the majority of patients with severe angina unsuitable for conventional surgical treatment, (2) gratifying results in terms of improved anginal status and exercise tolerance are achieved, despite the lack of significant changes in myocardial perfusion at early follow-up and (3) TMLR through a thoracoscopic approach is a feasible procedure.

Aged↗
PubMed1998

Interindividual variability of histamine N-methyltransferase in the human liver and kidney.

1. The aim was to investigate the possibility of interindividual variability of histamine N-methyltransferase (HNMT) in the human liver and renal cortex. The activity of HNMT was measured in 99 specimens of the human liver and in 75 specimens of the renal cortex. 2. In the liver the activity of HNMT was positively skewed. It ranged 2.9-fold with a median of 1.72 pmol/min/mg. In the renal cortex the activity of HNMT was normally distributed and ranged 2.6-fold with a mean and coefficient of variation of 1.35 pmol/min/mg and 21%, respectively. 3. The activities of catechol methyltransferase and thiopurine methyltransferase were measured in the renal cortex and any correlations with HNMT activity were assessed. There was a weak but significant correlation (r = 0.294, p = 0.010) between HNMT and catechol methyltransferase activities whereas HNMT activity was not correlated with thiopurine methyltransferase activity. 4. These results are consistent with the view that HNMT is well expressed in the human liver and renal cortex and that it varies among subjects.

Catechol O-Methyltransferase↗
PubMed1997

Transmyocardial laser revascularization using a thoracoscopic approach.

Transmyocardial revascularization is a new technique aimed to improve perfusion of the ischemic myocardium by creating transmyocardial channels with a laser. This report demonstrates that transmyocardial revascularization with a holmium laser can be performed through a thoracoscopic approach.

Coronary Disease↗
PubMed1997

Long-term survival in pancreatic cancer: pylorus-preserving versus Whipple pancreatoduodenectomy.

BACKGROUND: This study compared long-term survival in pancreatic or periampullary cancer treated with Whipple pancreatoduodenectomy (PD) and pylorus-preserving pancreatoduodenectomy (PPPD). METHODS: Two hundred twenty-one patients with pancreatic head or periampullary cancer were treated. Prognostic variables included age, gender, type and period of operation, and tumor stage. In the ductal adenocarcinomas variables also included tumor and node status, type of lymphadenectomy, pathologic grade, and presence of microscopic residual tumor. The end point was death as a result of neoplastic recurrence. Survival curves were estimated by using the Kaplan-Meier method, and multifactorial analysis was also performed on the data from the ductal adenocarcinoma group. RESULTS: The mortality rate was 8.2% in the PD group versus 7.0% in the PPPD group. Morbidity rates were 34.4% for PD and 45.8% for PPPD. Five-year survival was 9.6% in the ductal adenocarcinoma and 63.8% in the periampullary carcinoma groups. Univariate analysis failed to show statistically significant differences in survival curves between the two treatments in either patient group. Correcting for multiple variables in the ductal adenocarcinoma group did not reveal any significant differences in survival rates between the two treatments. CONCLUSIONS: PPPD was as successful as classic PD in the treatment of ductal adenocarcinoma and periampullary cancer of the pancreas. Long-term survival was not influenced by the type of resection.

Adenocarcinoma↗
PubMed1996

Management and follow-up of 78 giant haemangiomas of the liver.

The natural history and appropriate treatment of giant liver haemangioma remain poorly defined. The diagnostic strategy and the results of a longitudinal study of 78 such lesions are described. Sixteen resected patients and 62 with asymptomatic giant haemangiomas were entered into a follow-up programme consisting of clinical assessment and abdominal ultrasonography every 6 months. Resection was considered only for symptomatic patients (14 cases) and rapidly growing lesions (two cases). The mean follow-up was 36 months for the resected patients and 55 months for the observed group. Surgery permanently relieved symptoms. No recurrence of haemangioma was observed. Some 32 of 36 unresected lesions followed up remained stable in size. Minor changes were observed in four of 36. None ruptured or became symptomatic. It is concluded that asymptomatic large haemangiomas can be managed safely by observation. However, the occasional occurrence of rapid growth might represent a further indication for resection and justifies strict imaging follow-up. The pattern of growth, rather than absolute size, of a lesion is suggested for selection of asymptomatic patients who might benefit from preventive surgical excision. When feasible, the authors prefer enucleation to remove giant haemangiomas.

Adult↗
PubMed1996

Variability in the rate of 6-mercaptopurine methylation in the erythrocytes, liver and kidney in an Italian population.

OBJECTIVE: The polymorphism of erythrocyte thiopurine methyltransferase (TPMT) is genetically regulated as an autosomal codominant trait, and so should be congenital. RESULTS: We tested this hypothesis by measuring TPMT activity in erythrocyte preparations from adults and newborns and observed polymorphic distribution of TPMT activity in the adult and newborn erythrocytes. The activity of TPMT was higher in red cells from the newborns than adults. The frequency distribution of TPMT activity was also investigated in the liver and kidney. In the kidney, TPMT activity fell into two subgroups, whereas in the liver the distribution pattern was more complex. The activity of TPMT in erythrocytes and liver from the same subject was correlated, but the values of only half the cases fell within the 95% confidence limits, suggesting that the control of hepatic and/or erythrocyte TPMT is multifactorial.

Adolescent↗
PubMed1996

Laparoscopic Exposure of the Pancreas and Staging of Pancreatic Cancer.

Laparoscopy combined with laparoscopic contact ultrasonography was recently proposed as a new and effective method for staging and assessment of resectability in pancreatic cancer. In order to limit the occurrence of false-negative findings, the laparoscopic technique should be as close as possible to the equivalent laparotomic procedure. That includes opening of the lesser sac, which is best achieved through an infragastric route, with resulting wide exposure of the pancreatic body and tail. Laparoscopic contact ultrasonography is then performed for the purpose to define tumor limits, study relationships with major vessels, and assess limphnodal invasion. The results of this procedure in a series of 25 patients are discussed in this report. It is concluded that laparoscopic staging of pancreatic cancer is safe and effective in achieving the goal of avoiding unnecessary laparotomies and selecting candidates for surgical resection.

Journal Article↗
PubMed1996

Captopril methylation in human liver and kidney: interindividual variability.

1. The methylation of captopril was studied in the microsomal fraction obtained from 87 specimens of human liver and 70 specimens of human renal cortex. 2. The rate captopril methylation ranged over one order of magnitude in the liver and kidney. In the human liver, the mean (+/- SD) rate of captopril methylation (pmol/min/mg) was significantly (p < 0.001) greater in women (199 +/- 97) than in men (126 +/- 88), whereas in the kidney no sex-difference was observed, and the mean (+/- SD) of all cases was 47 +/- 23 pmol/min/mg. 3. In the kidney, the statistical analysis revealed the presence of two subgroups in the rate of captopril methylation and their mean (+/- SD) estimates were 42.5 +/- 13.9 and 90.3 +/- 12.0 pmol/min/mg (p < 0.05). Of the population, 84% fell in the former and the remaining 16% in the latter subgroup. 4. Captopril is mainly eliminated by metabolism and its bioavailability is 65%. Methylation is one of the metabolic routes of captopril and its variability may contribute, to some extent, to modulate the intracellular concentration of this drug.

Adult↗
PubMed1995

Comparative evaluation of contact ultrasonography and transcystic cholangiography during laparoscopic cholecystectomy: a prospective study.

BACKGROUND: The role of intraoperative cholangiography (IOC) during laparoscopic cholecystectomy (LC) is controversial. While many advocate its routine use, others argue for a selective approach. Recent reports showed laparoscopic contact ultrasonography (LCU) as a viable alternative to IOC. However, no prospective data were available to compare the accuracy, efficacy, and safety of the two diagnostic procedures. OBJECTIVE: To evaluate the benefits and disadvantages of LCU and IOC during LC. METHODS: Seventy-eight patients who underwent LC at Pisa (Italy) and Dundee (Scotland) university hospitals were entered in a prospective data registry. Details of operative technique and results of LCU and IOC were analyzed by reviewing videotape recordings of each procedure. RESULTS: Laparoscopic cholecystectomy was achieved in 73 patients, with five requiring conversion to the open procedure. The success rate of IOC was 90% (64/71). Performance of IOC demanded more than twice the time needed for LCU. Eleven percent (8/71) of cholangiograms were abnormal, with a false-positive rate of 1% (1/71). Laparoscopic contact ultrasonography detected all four instances of unsuspected ductal stones but none of the three cases of anomalous biliary anatomy. Clinically relevant incidental findings were picked up by LCU in six patients. CONCLUSIONS: Laparoscopic contact ultrasonography proved to be extremely accurate in the detection of ductal stones but less reliable in the disclosure of anomalous biliary anatomy. The essential role of IOC in providing a clear spatial display of the biliary tract was confirmed. Since the two procedures are complementary, their combined use is advisable in difficult LC to avoid retained common bile duct stones and prevent iatrogenic complications.

Adenoma↗
PubMed1995

Unsuspected choledochal cyst during laparoscopic cholecystectomy.

Cystic dilation of the extrahepatic bile ducts is rarely encountered during elective biliary surgery planned for different indications. We report here on a patient with unremarkable preoperative workup and normal intraoperative anatomy of the cystic pedicle in whom a type I choledochal cyst containing a large stone was detected by the combined use of laparoscopic contact ultrasonography and intraoperative cholangiography. This case report highlights the importance of intraoperative imaging modalities of the ductal system not only in preventing iatrogenic injuries and their related complications, but also in detecting unsuspected associated biliary pathology which might significantly change the course of surgical intervention.

Adult↗
PubMed1995

Hepatic cryotherapy for liver tumors. Development and clinical evaluation of a high-efficiency insulated multineedle probe system for open and laparoscopic use.

A high-efficiency hepatic cryosurgical unit has been developed and evaluated. It is capable of simultaneously driving three implantable insulated cryoneedle probes. The system has been used to treat 18 patients with secondary and 4 patients with primary liver cancer: open (n = 12), total laparoscopic (n = 6), laparoscopic assisted (n = 4). In three patient laparoscopic cryotherapy was repeated inside 6 months. Intraoperative bleeding was encountered in three patients undergoing high-volume hepatic freezing but the bleeding was easily controlled. A fall in the core body temperature was encountered in 10 out of 22 patients and averaged 0.4 degree C. There was one postoperative death from liver failure in an 80-year-old patient in whom a large hepatoma was frozen. The most consistent postoperative biochemical change was hyperbilirubinaemia (n = 3). A right-sided pleural effusion developed in two patients after freezing of lesions on the superior surface of the right lobe. A survival benefit was encountered in three patients, one with central cholangiocarcinoma and the other two with large solitary secondary deposits (melanoma, colon cancer). Seven patients with multiple metastases and two patients with large hepatomas developed recurrence at the frozen site or elsewhere in the liver inside 12 months of follow-up and no clinical benefit could be demonstrated by cryotherapy in this group. In nine patients, the follow-up has been too short (< 18 months) to permit any conclusion on outcome. The current limitations of hepatic cryotherapy are largely due to incomplete tumor destruction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Glutathione conjugation with 1-chloro-2,4-dinitrobenzene (CDNB): interindividual variability in human liver, lung, kidney and intestine.

The rate of glutathione conjugation with 1-chloro-2,4-dinitrobenzene (CDNB) was measured in specimens of human liver (n = 93), sigmoid colon (n = 56), renal cortex (n = 67) and lung (n = 68). In the liver there was a weak but significant (r = - 0.247 p = 0.017) negative correlation between the activity of glutathione transferase and the liver donor's age. Such a correlation was not found in the renal cortex, lung and colon. In the renal cortex and in lung the rate of glutathione conjugation with CDNB was a little but significantly (p < 0.05) higher in women than men, whereas no sex-dependent difference was observed in the liver and colon. The distribution of glutathione transferase activity was polymorphic in the mucosa of colon and renal cortex of men but not in that of women. Smoking seems not to affect the glutathione conjugation rate with CDNB in lung. The activity of glutathione transferase was 2-, 6-, and 7-fold greater in liver than in the renal cortex, lung and colon, respectively. There was a large interindividual variability of the hepatic glutathione transferase activity, and because this variability, 15% of the population studied catalyzed the glutathione conjugation with CDNB at a rate similar to those of the renal cortex and duodenum. The subjects with low expression of the hepatic glutathione transferase should be more exposed to the effects of toxic and carcinogenic compounds.

Adult↗