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C Pasquali

Publications and source records attributed to C Pasquali.

At least 55 records · Page 3Linked to original sources
PubMed1996

Two-dimensional gel electrophoresis of Escherichia coli homogenates: the Escherichia coli SWISS-2DPAGE database.

Numerous Escherichia coli proteins have already been characterized by two-dimensional gel electrophoresis (2-D PAGE), using carrier ampholytes in the first dimension (VanBogelen, R. A., Sankar, P., Clark, R. L., Bogan, J. A. and Neidhardt, F. C., Electrophoresis 1992, 13, 1014-1054). We present here a reference protein map of E. coli obtained with immobilized pH gradients (IPG) and available in a SWISS-2DPAGE format. Out of the protein spots identified in the E. coli gene protein database by Neidhardt's group, 153 have been identified in the E. coli gene protein database by Neihardt's group, 153 have been identified on the E. coli SWISS-2DPAGE database map by gel comparison and most of them were confirmed either by the analysis of amino acid composition (AAC) and/or N-terminal microsequencing. Additionally, five as yet unsequenced proteins were found. The E. coli SWISS-2DPAGE database is part of the ExPASy molecular biology server accessible through the Word Wide Web network.

Amino Acid Sequence↗
PubMed1996

Endosomal fractions from viral K-ras-transformed MDCK cells reveal transformation specific changes on two-dimensional gel maps.

We have investigated the effects of viral Kirsten ras oncogene expression in Madin-Darby canine kidney (MDCK) II epithelial cell on the differential protein expression of organelle proteins. MDCK cells, stably transformed via infection with a helper-independent retroviral vector construct, were grown on permeable filter supports. Whereas normal cells form highly polarized monolayers, ras-transformed cells display an unpolarized phenotype, detaching from the substratum and developing multilayers (Schoenenberger, C.-A. et al., J. Cell Biol. 1991, 112, 873-889). We postulate that this breakdown of epithelial polarity reflects disturbed intracellular protein transport and sorting, namely, proteins will no longer be sorted correctly in intracellular organelles and will therefore not reach their appropriate target membrane. Here we emphasize the role of endosomes as sorting platform in epithelial cells. We found significant differences in the molecular composition of endosomes from normal vs. oncogenic transformed epithelial cells, strengthening previous evidence indicating that oncogenic transformation results in abnormal expression of normal genes (Celis, J. E., Olsen, E., Electrophoresis 1994, 15, 309-344) as well as the expression of new ones (Huber, L. A. et al., Electrophoresis 1994, 15, 468-473).

Animals↗
PubMed1996

From proteins to proteomes: large scale protein identification by two-dimensional electrophoresis and amino acid analysis.

Separation and identification of proteins by two-dimensional (2-D) electrophoresis can be used for protein-based gene expression analysis. In this report single protein spots, from polyvinylidene difluoride blots of micropreparative E. coli 2-D gels, were rapidly and economically identified by matching their amino acid composition, estimated pI and molecular weight against all E. coli entries in the SWISS-PROT database. Thirty proteins from an E. coli 2-D map were analyzed and identities assigned. Three of the proteins were unknown. By protein sequencing analysis, 20 of the 27 proteins were correctly identified. Importantly, correct identifications showed unambiguous "correct" score patterns. While incorrect protein identifications also showed distinctive score patterns, indicating that protein must be identified by other means. These techniques allow large-scale screening of the protein complement of simple organisms, or tissues in normal and disease states. The computer program described here is accessible via the World Wide Web at URL address (http:@expasy.hcuge.ch/).

Amino Acids↗
PubMed1996

An easier technique for end to end pancreaticojejunostomy.

Breakdown of the pancreaticoenterostomy is responsible for a number of complications and for the high mortality associated with pancreaticoduodenectomy. Although in recent years the postoperative mortality has dropped to less than 10% and in some to less than 5%, pancreatic fistula remains the most common and troublesome complication. Various procedures, such as duct ligation or occlusion, resection of the pancreatic stump or pancreaticogastrostomy, have been proposed to treat the pancreatic stump when it is considered unsuitable for jejunal anastomosis. A little trick permitted us to perform 41 consecutive end to end pancreaticojejunostomies, irrespective of the conditions of the pancreatic stump, with only 3 pancreatic fistulas (7%) and without fistula related deaths.

Female↗
PubMed1995

Inside SWISS-2DPAGE database.

Several two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) databases have been established and updated for more than 15 years. Only recently have developments of computer networks and high-speed transfer protocols provided the required tools for sharing comprehensive and hypermedia 2-D PAGE databases. This publication describes the SWISS-2DPAGE database structure. Proteins present in samples of human tissue, cells, cell lines and body fluids are assembled and described in an accessible uniform format. SWISS-2DPAGE can be freely accessed through the World-Wide Web (WWW) network on the ExPASy molecular biology server.

Body Fluids↗
PubMed1995

Solitary true cyst of the pancreas in adults. Report of three cases and review of the literature.

Solitary true cysts of the pancreas are extremely rare: to date, only eight cases have been reported in the English literature, four of which had clinical significance. An additional three cases of solitary true cysts of the pancreas are presented. One patient was incidentally found at operation, performed for other disease, to have a cystic lesion in the body of the pancreas; the other two patients experienced abdominal pain and nausea. Abdominal US, CT, and MR showed a unilocular cyst in the body and tail of the pancreas. In both cases, preoperative diagnosis of pancreatic cystic neoplasm was made. Two patients underwent excision of the mass and one distal pancreatectomy. Analysis of the cyst fluid revealed high CA 19-9 levels in two and CA 125 levels in one case. All cysts were lined by cuboidal epithelium, without morphological alterations. Preoperative differential diagnosis with the most common cystic pancreatic lesions (inflammatory or neoplastic) is difficult.

Adult↗
PubMed1995

Pancreaticoduodenojejunostomy for chronic pancreatitis presenting with an inflammatory mass in the head of the pancreas.

An inflammatory mass in the head of the pancreas is reported in 18-50% of patients with chronic pancreatitis. When the clinical history is misleading, differential diagnosis between chronic pancreatitis and pancreatic cancer may be very difficult. Pancreaticoduodenectomy is considered the treatment of choice, if cancer is still suspected despite negative biopsy. From January 1987 to December 1992 we performed 42 pancreaticoduodenectomies, 36 for malignancies of the pancreaticoduodenal area and 6 for chronic pancreatitis suspected to have a pancreatic cancer. In three additional cases of chronic pancreatitis, we performed a pancreaticoduodenojejunal anastomosis after complete opening of the pancreatic duct and excision of the papilla of Vater. Frozen section and definitive histological examination of the pancreas and ampulla excluded malignance in all three patients. They are alive and well 60, 36, and 20 months after operation. With this procedure, frozen-section examination of the distal part of the pancreatic and biliary duct, the papilla, and the periductal pancreatic tissue can be performed, while this is impossible with the usual pancreaticojejunostomy. We can therefore reasonably exclude a small cancer of the periampullary area and perform a wider derivative procedure, instead of a pancreaticoduodenectomy, in patients with an inflammatory mass of the head of the pancreas.

Anastomosis, Surgical↗
PubMed1995

Evaluation of cyst fluid analysis in the diagnosis of pancreatic cysts.

The pre-operative differential diagnosis of pancreatic cystic lesions is often difficult because of the lack of reliable clinical or radiological criteria. In order to improve the pre-operative recognition of these lesions, we performed cyst fluid analysis for enzymes (amylase and lipase), tumour markers (CEA, CA 19-9, CA 125, CA 72-4), and cytology in 52 pancreatic cysts. The cases included 21 pseudocysts, 12 mucinous cystic neoplasms, 7 ductal carcinomas, 7 benign lesions, and 5 rare malignancies observed from 1989 to 1994. Cyst fluid amylase, lipase, CEA, and CA 19-9 were variable and not discriminant between the groups. CA 125 fluid levels were high in 63% of malignant cysts. CA 72-4 fluid levels were significantly higher in mucinous cystic tumours than in pseudocysts (p < 0.0001), showing 95% specificity in detecting mucinous or malignant cysts. Cytology showed a sensitivity of 61% and a specificity of 100%. CA 72-4 determination raised the sensitivity of cytology to 92% in detecting mucinous or malignant cysts. This study confirms the low sensitivity of cytologic examination and low amylase specificity in distinguishing cystic neoplasms from pseudocysts. Cyst tumour markers assay is useful to improve the sensitivity of cytology, and CA 72-4 shows the best specificity in detecting (pre)malignant neoplasms.

Adenocarcinoma, Mucinous↗
PubMed1995

The role of 111In-octreotide scintigraphy in the detection of APUD tumours: our experience in eighteen patients.

111In-Octreotide scintigraphy has been recently proposed as a sensitive technique for the detection of neuroendocrine tumours, based on the high radiotracer affinity towards the somatostatin receptors expressed by the APUD-system cells. In the present study, a group of 18 patients with carcinoid tumours and gastrointestinal (GI) apudomas was investigated to assess the accuracy of Octreotide scintigraphy in localizing primitive, recurrent or metastatic lesions. Both planar and SPECT studies were obtained 4 hours after the i.v. injection of 111In-Octreotide (111 MBq); planar images were also carried out 24 hours later. In accordance with other authors, the sensitivity of the method was found to be very high (94%) in our group of patients; only in one case of nesidioblastosis was the scintigraphy negative. No differences in sensitivity were observed between the planar and SPECT studies, but the latter provided a better topographic localization of the neoplastic foci. It should be pointed out that in 7 cases (3 primitive, 1 recurrent and 3 metastatic lesions) scintigraphy correctly localized the tumour, when the other morphological techniques, such as echography, computed tomography or magnetic resonance, failed. On the basis of our data, we believe that Octreotide scintigraphy should be the first study performed in the evaluation of patients affected by APUD tumours.

Angiography↗
PubMed1995

Sharing of worldwide spread knowledge using hypermedia facilities & fast communication protocols (Mosaic and World Wide Web): the example of ExPASy.

The sharing of knowledge worldwide using hypermedia facilities and fast communication protocols (i.e., Mosaic and World Wide Web) provides a growth capacity with tremendous versatility and efficacy. The example of ExPASy, a molecular biology server developed at the University Hospital of Geneva, is striking. ExPASy provides hypermedia facilities to browse through several up-to-date biological and medical databases around the world and to link information from protein maps to genome information and diseases. Its extensive access is open through World Wide Web. Its concept could be extended to patient data including texts, laboratory data, relevant literature findings, sounds, images and movies. A new hypermedia culture is spreading very rapidly where the international fast transmission of documents is the central element. It is part of the emerging new "information society".

Artificial Intelligence↗
PubMed1994

Two-dimensional polyacrylamide gel electrophoresis analysis of cryoglobulins and identification of an IgM-associated peptide.

The clonality of immunoglobulins (Igs) in cryoprecipitates (n = 41) was studied by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Our series included 24 cryoglobulins characterized by immunofixation electrophoresis (IF), 12 'trace amount' cryoglobulins, defined by a protein content in the precipitate of less than 0.05 mg/ml of serum, and five cryoglobulins of undetermined protein composition by IF. 2-D PAGE analysis showed polyclonal IgG associated either with monoclonal Igs (type II cryoglobulins; n = 14) or with polyclonal IgM (type III cryoglobulins; n = 14). In ten cryoprecipitates (two 'trace amount' cryoglobulins as well as seven of 19 type II and as one of five type III cryoglobulins by IF) polyclonal IgG were associated with a mixture of polyclonal and monoclonal IgM. These cryoglobulins were tentatively named type II-III cryoglobulins. A monoclonal IgM was observed in one cryoprecipitate (type I cryoglobulins). Two cryoglobulins presented unexpected 2-D patterns, characterized by the presence of oligoclonal IgM, with trace amounts of Igs of different isotypes (tentatively named type II-III(variant) cryoglobulins). A peptide of 44 kDa with a pI of 5.45 was observed in all cryoglobulins containing IgM (n = 40). This peptide was also present in purified monoclonal or polyclonal IgM fractions. N-terminal microsequencing (12 amino acid residues) revealed that this IgM-associated peptide was an unknown protein. Our results highlight the role of 2-D PAGE as an aid in the analysis of cryoglobulins.

Amino Acid Sequence↗
PubMed1994

Radical resection for ampullary carcinoma: long-term results.

Of 36 patients with carcinoma of the ampulla of Vater who underwent surgery between 1971 and 1990, 31 had a radical operation. There was one operative death. The overall 5- and 10-year survival rates were 56 and 37 per cent respectively. Survival was significantly influenced by tumour stage (P = 0.0002), lymph node status (P = 0.006) and the degree of differentiation of the lesion (P = 0.01). Three patients developed local recurrence after local excision of the tumour. Local or hepatic recurrence was common, even 5 years after pancreatoduodenectomy (four of 18 patients who suffered relapse). Radical resection can be curative in selected patients with ampullary carcinoma but late recurrence suggests the need for careful lifelong follow-up.

Adult↗
PubMed1994

Surgical treatment of insulinoma.

The role of preoperative and intraoperative procedures for the localization of insulinoma has been extensively debated. Transhepatic portal vein sampling before surgery has been recommended when other tests fail to localize the tumour. To determine the role of different investigations, 53 patients with insulinoma, four with hyperplasia or nesidioblastosis and one with insulin autoimmune syndrome were studied. Patients were operated on in three consecutive periods during each of which a different localization procedure was considered to represent the 'gold standard'. During the first period, of 16 patients (including one with hyperplasia) investigated by arteriography, 13 underwent successful resection. Tumours in the other three patients with insulinoma were resected at a second operation, one during the first period and one each during the second and third periods. During the second period, 28 patients underwent exploration after transhepatic portal sampling: the tumour was found in all 26 patients with insulinoma operated on in this hospital, one patient with hyperplasia is receiving medical treatment and one patient had unsuccessful surgical exploration elsewhere despite positive findings on arteriography and transhepatic portal sampling performed in this department. During the third period 13 procedures were performed. All were successful using intraoperative ultrasonography without transhepatic portal sampling. In three further patients intraoperative localization failed because of non-adenomatous beta cell disease. Left-sided resection successfully cured symptoms in two patients with hyperplasia and prompted the diagnosis of insulin autoimmune syndrome. High success rates for surgical treatment of insulinoma can be achieved with transhepatic portal vein sampling or intraoperative ultrasonography. Transhepatic portal sampling is therefore unnecessary before a first operation on the pancreas for insulinoma. In the rare failures of intraoperative localization of an insulinoma, a small left pancreatic resection can help to distinguish insulinoma from hyperplasia without precluding further segmental resection.

Adolescent↗
PubMed1994

Duodenal leiomyosarcoma mimicking a pancreatic pseudocyst.

A case of duodenal leiomyosarcoma presenting as a cystic mass is reported. Amylase, tumour markers levels in the cyst fluid and radiological findings suggested an inflammatory pancreatic pseudocyst. Exploratory laparotomy and frozen section examination showed a smooth muscle tumour of the duodenum. Pancreatoduodenectomy with pylorus-preser vation was performed and the patient remained symptom-free at 8 months follow-up.

Aged↗
PubMed1994

Clinical value of serum TAG-72 as a tumor marker for pancreatic carcinoma. Comparison with CA 19-9.

We evaluated the sensitivity and specificity of the carbohydrate antigen TAG-72 as a tumor marker for pancreatic cancer compared with the serum values of CA 19-9. Forty healthy controls, 58 patients with pancreatic carcinoma, and 45 patients with chronic pancreatitis were studied. In patients with pancreatic cancer, 47/58 (81%) and 26/58 (45%) had raised serum levels of CA 19-9 and TAG-72, respectively; the sensitivity of the tests was not influenced by jaundice. In the chronic pancreatitis patients, both CA 19-9 and TAG-72 were elevated in 2/45 patients (4.4%). Both tests showed a specificity of 95%. Consequently, the sensitivity of TAG-72 was too low compared with CA 19-9. Moreover, serum TAG-72 could not detect small pancreatic cancers. High levels of both tumor markers were found in advanced stages of cancer. No advantage was found using both CA 19-9 and TAG-72 for improving the detection of pancreatic cancer. TAG-72 serum levels > 10 U/mL are closely related to unresectability of the tumor. Only 4/17 (23%) of patients with resectable tumor had high TAG-72 levels. Serum TAG-72 expression seems to be more frequent in poorly-differentiated tumors than in well-differentiated cancers (56 vs 30% positivity rate).

Adult↗
PubMed1994

The SWISS-2DPAGE database of two-dimensional polyacrylamide gel electrophoresis.

SWISS-2DPAGE is a database of proteins identified on two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), created and maintained at the University Hospital of Geneva in collaboration with the Department of Medical Biochemistry of Geneva University. The proteins have been identified on various 2-D PAGE reference maps by microsequencing, immunoblotting, gel comparison and amino acid composition.

Blotting, Western↗
PubMed1994

CA 50 compared with CA 19-9 as a serum tumour marker for pancreatic carcinoma.

This study compared the sensitivity and specificity of CA 50 and CA 19-9 as serum tumour markers for pancreatic cancer. One hundred and seventy one subjects were evaluated: 50 healthy controls, 50 patients with pancreatic carcinoma and 71 patients with chronic pancreatitis. Eighty per cent of the pancreatic cancer patients had raised CA 19-9 serum levels and 82% had raised CA 50 serum levels. In the group of patients ith chronic pancreatitis, false positive tests occurred in 8.4% for CA 19-9 and 11.3% for CA 50. For both markers the serum level showed a severe elevation in the advanced stage of cancer disease. Despite the good sensitivity and specificity of CA 50 as a serum tumour marker for pancreatic carcinoma, no major advantage was found compared to CA 19-9. Moreover, if the CA 50 cut-off, level is raised to 85 U/ml to exclude overlap with chronic pancreatitis, sensitivity falls sharply to 46% compared with 72% for CA 19-9 when a 100 U/ml cut-off level is used.

Adult↗