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P Fogar

Publications and source records attributed to P Fogar.

At least 19 recordsLinked to original sources

Insights in the laboratory diagnosis of celiac disease.

The present report focuses on the diagnosis of celiac disease and its pathogenesis, which depends on a genetic predisposition (HLA DQ2 or DQ8 haplotypes), gluten ingestion and T cell activation, type II transglutaminase (TG2), the autoantigen recognized by the antiendomysial antibody playing a key role. IgA class antibody anti-environmental (gliadin) and endogenous (TG2) antigens are present in the sera of patients with celiac disease. The anti-TG2 antibody has the best available diagnostic accuracy, especially when measured employing second generation ELISA tests, which use the human TG2 antigen, or immunochemiluminescent assay, which is highly sensitive. A diagnosis of celiac disease must always be confirmed by the histological evaluation of multiple duodenal mucosa specimens, and serology is recommended for follow-up controls.

Antibodies↗

Killer genes in pancreatic cancer therapy.

This review describes: 1. The main genetic alterations found in pancreatic cancer (EGF-R overexpression, SST-2 somatostatin receptor loss of expression, k-ras, p53 mutations and DPC4 mutations) and the effect of their replacements by gene therapy on tumor growth; 2. The use of suicide genes (HSV-TK and CD) for pancreatic cancer gene therapy in vitro and in vivo; 3. The implications for pancreatic cancer treatment when using cytotoxic bacterial toxins; 4. Viral and non-viral delivery systems for the transfer of therapeutical genes into pancreatic cancer cells. Overall both the correction of pancreatic cancer cells main genetic alterations and the use of suicide genes allow only partial tumor regression in vitro and in vivo. The lack of a 100% effect for any studied strategy considered alone, indicates the need for combined therapies to achieve a satisfactory treatment of this tumor.

Animals↗

Altered glucose metabolism and proteolysis in pancreatic cancer cell conditioned myoblasts: searching for a gene expression pattern with a microarray analysis of 5000 skeletal muscle genes.

BACKGROUND AND AIMS: We verified whether conditioned media (CM) from pancreatic cancer cell lines (MIAPaCa2, CAPAN-1, PANC-1, BxPC3) alter glucose metabolism and gene expression profiles (microarray experiment with a platform of 5000 skeletal muscle cDNA) in mice myoblasts. METHODS: Myoblasts were incubated with control or pancreatic cancer CM for 24 and 48 hours. RESULTS: Lactate significantly increased in CM compared with non-conditioned myoblasts. No variations in expression levels of the main genes involved in glycolysis were found in CM myoblasts. Propionyl coenzyme A carboxylase and isocitrate dehydrogenase 3 beta genes, which encode enzymes of the tricarboxylic acid cycle, were overexpressed, while IGFIIR and VAMP5 genes were underexpressed in CM myoblasts. PAFAH1B1 and BCL-2 genes (intracellular signal transduction) and the serine protease cathepsin G (proteolysis), were overexpressed in CM myoblasts. Tyrosine accumulation in CM myoblasts suggested that proteolysis overcomes protein synthesis. Sorcin, actin alpha, troponin T1, and filamin A were underexpressed in CM myoblasts. CONCLUSIONS: Our findings demonstrate that pancreatic cancer cell conditioned media enhanced lactate production and induced proteolysis, possibly by altering expression levels of a large number of genes, not only those involved in protein biosynthesis and degradation or glucose metabolism, but also those involved in the tricarboxylic acid cycle and in vesicle traffic.

Aged↗

Suicide gene therapy with HSV-TK in pancreatic cancer has no effect in vivo in a mouse model.

AIM: To study in vivo whether pancreatic cancer tumour growth and metastasis can be modified by a gene construct with HSV-TK suicide gene and IL2 co-expression. METHODS: Seventy-eight female SCID mice were i.p. inoculated with retrovirally transduced or control MIA PaCa 2, CAPAN-1 and PANC-1 cell lines. The animals were then randomly selected for saline or ganciclovir (GCV) treatment from the second week, for a total of two weeks. RESULTS: Most inoculated mice developed tumour nodules and spleen metastases. The liver was colonized by control CAPAN-1 and MIA PaCa 2, but not by PANC-1. Tumours in transduced MIA PaCa 2 cell injected mice were smaller, and in transduced CAPAN-1 injected mice larger, than in control-inoculated mice. There were increased pancreatic and decreased spleen metastases from transduced CAPAN-1, and diminished liver involvement from transduced MIA PaCa 2. No differences were found between mice inoculated with transduced and control PANC-1 cell lines. GCV treatment had no effect on tumour's size or metastases. CONCLUSIONS: The HSV-TK suicide gene does not confer GCV sensitivity to pancreatic cancer in this in vivo model. Different pancreatic cancer cell lines cause different growth and metastasis patterns after inoculation in SCID mice, possibly because of variations in their inherent characteristics. The different effects of our vector on cell growth and metastasis may be attributable to the effects of the immunostimulatory cytokine IL2.

Animals↗

Helicobacter pylori virulence genes and host IL-1RN and IL-1beta genes interplay in favouring the development of peptic ulcer and intestinal metaplasia.

Helicobacter pylori infection outcome might depend on genotypic polymorphisms of both the bacterium and the host. We ascertained: (1) the functionality of H. pylori oipA gene; (2) the polymorphism of the hostinterleukin (IL-1beta) gene (-31 C/T) and of the IL-1RN gene (intron 2 VNTR); (3) the association between the above genes and the histological and pathological outcome of H. pylori infection. One hundred and sixty-five H. pylori positive and 137 H. pylori negative subjects (23 gastric adenocarcinoma, 58 peptic ulcer, 221 gastritis) were studied. oipA was sequenced, IL-1beta was RFLP analysed. Antral and body mucosal biopsies were histologically evaluated. Functional oipA genes were correlated with cagA gene; both genes were significantly associated with gastritis activity, peptic ulcer and gastric adenocarcinoma. In these patients heterozygousIL-1RN 1/2 and IL-1beta C/T genotypes were more frequent than in gastritis patients. Intestinal metaplasia was associated with cagA, functional oipA and IL-1RN 2 allele. In conclusion, peptic ulcer and the preneoplastic intestinal metaplasia are associated with H. pylori virulence genes and with IL-1RN 2 host allele. An interplay between bacterial virulence factors and cytokines genotypes, is probably the main route causing H. pylori infection to lead to benign mild disease, benign severe disease or preneoplastic lesions.

Adenocarcinoma↗

ME-PCR for the identification of mutated K-ras in serum and bile of pancreatic cancer patients: an unsatisfactory technique for clinical applications.

Our aim was to assess the clinical reliability of mutated K-ras detection in serum or bile for the diagnosis of pancreatic cancer using ME-PCR. DNA was extracted from 1 ml serum obtained from 29 patients with pancreatic cancer and 12 control subjects. ME-PCR was optimized using a mixture of normal DNA added with different amounts of mutated DNA. The analysis of sera obtained from the 29 patients and of bile obtained from 11 pancreatic cancer patients demonstrated the presence of mutated K-ras in two (6.9%) and four cases (36%). By contrast K-ras was not amplifiable in any of the 12 serum samples obtained from healthy controls. In conclusion the DNA obtained from pancreatic cancer patients' sera is suitable for K-ras amplification and for the identification of codon 12 point mutations. However ME-PCR alone has an unsatisfactory sensitivity for the detection of pancreatic cancer using serum DNA as starting template.

Adult↗

Total PSA, free PSA/total PSA ratio, and molecular PSA detection in prostate cancer: which is clinically effective and when?

OBJECTIVES: To ascertain when the serum determination of the free prostate-specific antigen (PSA)/total PSA (fPSA/tPSA) ratio is clinically useful, and whether the identification of PSA or prostate-specific membrane antigen (PSM) mRNA in circulating cells has diagnostic advantages over the determination of their protein product. METHODS: fPSA, tPSA, and the fPSA/tPSA ratio were determined in the sera of 50 men with benign nonprostatic urologic diseases (EPD), 112 patients with prostate cancer (PCa), and 218 with benign prostatic hyperplasia (BPH). mRNA was extracted from the circulating mononuclear cells of 13 EPD samples, 25 PCa samples, and 38 BPH samples. PSA and PSM mRNA signals were identified in these samples by means of reverse transcriptase-polymerase chain reaction. RESULTS: Overall, at a fixed specificity of 95%, the sensitivity of tPSA was 19% and that of the fPSA/tPSA ratio was 40% in distinguishing PCa from BPH. The fPSA/tPSA ratio allowed the discrimination of PCa from BPH with satisfactory sensitivity and specificity when considering patients less than 60 years of age (100% and 95%, respectively). PSA and PSM mRNA were positive in 1 and 7 of 13 EPD samples, 6 and 13 of 25 PCa samples, and 6 and 17 of 38 BPH samples. The Gleason score did not correlate with tPSA, the fPSA/tPSA ratio, PSA mRNA, or PSM mRNA. CONCLUSIONS: The serum determination of the fPSA/tPSA ratio is an excellent index of PCa for subjects younger than 60 years of age; the clinical utility of PSA mRNA identification in circulating cells needs to be validated by large follow-up studies, and the analysis of PSM mRNA seems to be of no clinical interest.

Aged↗

CEA mRNA identification in peripheral blood is feasible for colorectal, but not for gastric or pancreatic cancer staging.

OBJECTIVE: It has been suggested that the molecular identification of cancer cells in the circulation may be useful in predicting the presence of micrometastasis in several cancer types. The aim of the present study was therefore to assess the feasibility of CEA mRNA identification in blood for diagnosing and staging colorectal, gastric and pancreatic cancer. METHODS: We studied 16 control subjects, 69 patients with colorectal (CRC), 30 with gastric (GC), 27 with pancreatic cancer (PC) and 8 with benign diseases of the pancreatobiliary tree. At diagnosis CEA mRNA was identified in peripheral blood by means of a RT-PCR procedure. RESULTS: The specificity of this test in control subjects was 94%, and its sensitivity in identifying CRC, GC and PC were 34, 37 and 41%, respectively. False-positive findings were recorded in 25% patients with benign diseases. No association was found between CEA mRNA and stage in patients with GC or PC. In CRC patients, positive CEA mRNA findings were correlated with local spread (chi(2) = 14.6, p<0.01), lymph node (chi(2) = 18.95, p<0.001) and distant metastasis (chi(2) = 11.3, p<0.001). In these cases, CEA mRNA, but not CEA, was entered in stepwise discriminant analysis to classify the presence of lymph node metastasis. CONCLUSIONS: The molecular detection of micrometastasis in the blood by means of CEA mRNA identification is feasible for colorectal, but not for gastric or pancreatic cancer staging. Further studies are needed in order to define the clinical utility of this marker also in follow-up protocols.

Adult↗

Effect of cagA status on the sensitivity of enzyme immunoassay in diagnosing Helicobacter pylori-infected children.

BACKGROUND: The aims of our study were twofold. First, we sought to evaluate in symptomatic children the influence of the Helicobacter pylori genotype on gastritis, abdominal pain, and circulating anti-H. pylori IgG antibodies (anti-H. pylori IgG) or pepsinogen A (PGA) and C (PGC). Additionally, we sought to assess anti-H. pylori IgG, PGA, and PGC patterns in a large cohort (N = 921) of asymptomatic children. MATERIALS AND METHODS: In 183 symptomatic children, H. pylori infection and the presence of gastritis were evaluated by histology. In a subgroup of 20 H. pylori-positive children, the H. pylori genotype was evaluated also by polymerase chain reaction. Nine hundred and twenty-one asymptomatic children, aged 11 to 14 years, were studied by anti-H. pylori IgG, PGA, and PGC serum determination. RESULTS: The infection was found in 33 of 183 symptomatic children; among the 20 H. pylori-positive children for which the H. pylori genotype was available, cagA was present or absent in equal percentages. H. pylori infection was associated with more severe gastritis and higher serum levels of anti-H. pylori IgG and PGC but not with abdominal pain. In infected children, higher levels of anti-H. pylori IgG and the presence of abdominal pain were associated with infections caused by cagA-positive strains. In the cohort of 921 asymptomatic children, raised levels of anti-H. pylori IgG, PGA, and PGC were found in approximately 5% of the cases. CONCLUSIONS: Infection with cagA-positive H. pylori strains can be associated with increased frequency of reported abdominal pain and higher circulating levels of anti-H. pylori IgG. The serological assessment of H. pylori IgG using H. pylori antigens containing significant amounts of cagA protein may, therefore, underestimate the true prevalence of infection.

Abdominal Pain↗

[Biochemical markers of gastric functioning].

The serum determination of pepsinogen A (PGA) and pepsinogen C (PGC) might indicate gastric mucosal inflammation and atrophy. Body gastric mucosa produces both PGA and PGC, while antral mucosa produces only PGC. Therefore, diseases involving mainly the antrum, such as H. pylori infection, are mainly indicated by the variations in serum PGC than in serum PGA. In agreement, when the antral mucosa is infected by the more virulent cagA positive H. pylori strains, which cause severe inflammation, serum PGC significantly increases. Another indirect indicator of gastric inflammation is polymorphonuclear (PMN) oxidative burst after the stimulation with water extracts from H. pylori culture: this parameter is significantly increased in infected if compared to non-infected subjects. The higher oxidative burst response of peripheral PMN in infected patients, possibly consequent to the release of specific cytokines able to prime PMN towards H. pylori products, is unable to eliminate the infection, but it might concur in damaging the gastric mucosa.

Biomarkers↗

Portal but not peripheral serum levels of interleukin 6 could interfere with glucose metabolism in patients with pancreatic cancer.

UNLABELLED: Interleukin 6 (IL-6), an autocrine growth factor for many tumors, seems to favour tumor spread to the liver. Our aims were first to evaluate the pattern of portal and systemic IL-6 levels in patients with pancreatic cancer (PC, n = 18) and chronic pancreatitis (CP, n = 22) compared with controls (CS, n = 20); and second, to ascertain whether there was any relation between IL-6 levels and tumor spread or PC-associated Diabetes mellitus. For all subjects, a fasting serum sample was obtained from a cubital vein; a portal serum sample was obtained from nine PC and three CP patients. In cubital and portal sera we measured IL-6, interleukin 1 beta (IL-1b), CA 19-9, c-reactive protein (CRP) and amylase. Systemic IL-6 levels were significantly higher in PC patients than in CS. In PC, portal IL-6 levels were significantly higher than the corresponding systemic values. The same pattern was found in the three CP patients, whereas IL-1b, CA 19-9, CRP and amylase portal levels were the same as systemic values. No correlation was found between PC stage and systemic or portal IL-6 levels. Portal IL-6 levels were correlated with the corresponding fasting serum glucose values. A significant correlation was found between IL-6 values and CRP, ALT, total bilirubin, GGT and creatinine, but not amylase. IN CONCLUSION: (1) Portal IL-6, which is partly of pancreatic origin, is first metabolised in the liver; (2) Systemic IL-6 reflects hepatic and renal functions rather than local conditions in the pancreas; (3) IL-6 does not appear to influence PC spread; (4) IL-6, which is released in large amounts by the inflamed pancreas, may contribute to determining diabetes, thus interfering with the signal transducing pathways involved in glucose metabolism in liver cells.

Aged↗

Transforming growth factor beta, fibrogenesis and hyperglycemia in patients with chronic pancreatitis.

UNLABELLED: It has been suggested that transforming growth factor beta (TGFb) mediates liver fibrosis, which can be monitored by the serum determination of the N-terminal peptide of type III procollagen (PIIIP) and laminin. Fibrosis is also an important phenomenon in patients with chronic pancreatitis (CP). In 23 patients with CP, 38 with liver cirrhosis (LC) and 20 healthy controls we compared the serum patterns of PIIIP, laminin and TGFb and assessed whether in CP these markers are correlated with exocrine and endocrine function. In patients with LC, PIIIP and laminin levels were significantly higher, whereas TGFb levels were significantly lower than those of controls. In CP patients, no significant variations were found for PIIIP and laminin, although levels were high in 7/23 and in 5/23 patients, respectively. TGFb levels in CP patients were higher than those in LC patients, levels being raised in 6/23 patients. In LC patients an inverse correlation was found between PIIIP and TGFb, whereas in CP patients, a direct correlation was found between TGFb and PIIIP. Moreover, in CP patients, there was also a positive correlation between TGFb and fasting serum glucose levels, while laminin was correlated with PABA test results. IN CONCLUSION: serum biochemical markers of liver fibrosis can be considered of limited value in assessing pancreatic fibrosis; in liver cirrhosis there may be a negative feed-back regulation between TGFb production and the fibrogenetic process; and in chronic pancreatitis TGFb appears to favor fibrosis on the one hand and the development of hyperglycemia on the other.

Adult↗

Insulin-like growth factor-I, interleukin-1 alpha and beta in pancreatic cancer: role in tumor invasiveness and associated diabetes.

We evaluated levels of insulin-like growth factor-I and interleukin-1 alpha and beta in patients with pancreatic cancer; the role of these substances in tumor spread and in hyperglycemia was also investigated. Thirty pancreatic cancer patients (21 with hyperglycemia) were compared with others with diseases causing hyperglycemia [liver cirrhosis (14 cases, 12 with hyperglycemia), chronic pancreatitis (20 cases, 12 with hyperglycemia), type I diabetes mellitus (13 cases, all hyperglycemic)]. Insulin-like growth factor-I was significantly reduced in patients with liver cirrhosis, probably due to a reduced hepatic capacity for synthesis. It was increased in 6 of 30 pancreatic cancer patients; in these subjects it was correlated with alanine aminotransferase and C-peptide, but not with tumor diameter or the presence of metastases. Interleukin-1 alpha and beta were both elevated in pancreatic cancer patients. The former was high, while the latter was low when liver metastases were present. Neither was related to glucose or C-peptide levels. In summary, insulin-like growth factor-I levels are increased in some pancreatic cancer patients but this does not seem to favor tumor spread; however IGF-I could be involved influencing glucose homeostasis. Interleukin-1 alpha increased, while interleukin-1 beta decreased in pancreatic cancer patients with metastases, suggesting a different involvement of these two substances in pancreatic cancer spread.

Adult↗

Beta-cell function in pancreatic adenocarcinoma.

To evaluate beta-cell function in patients with pancreatic cancer, the glucagon stimulation test was performed in seven patients with pancreatic adenocarcinoma, seven patients with type I diabetes mellitus, seven patients with type II diabetes mellitus, and in seven healthy controls. C-peptide serum levels were determined before and after a 1-mg i.v. glucagon injection. Basal C-peptide values were normal or slightly increased in pancreatic cancer and type II diabetic patients and low in type I diabetic patients. Following glucagon stimulation, no significant increase was observed in C-peptide values of type I diabetics and pancreatic cancer patients, whereas significant increases occurred in controls and type II diabetics. It is concluded that the altered beta-cell function found in pancreatic cancer patients may lead to hyperglycemia, which is frequently associated with this tumor type.

Adenocarcinoma↗

Lipid peroxidation and renal tubular damage in chronic pancreatic diseases: is there any relationship?

Lipid peroxidation is one of the most important expression of oxidative stress induced by oxygen-derived free radicals. Here we evaluate the behavior of malondialdehyde (MDA) in the serum and urine from patients with chronic pancreatic diseases, with respect to patients with extra-pancreatic digestive diseases and glomerulonephritis. Serum and urinary phospholipase A2 (PLA2) activity was also determined, since this enzyme contributes to damage of plasma membranes. MDA and PLA2 levels increased in the sera from most of the patients with pancreatic and extra-pancreatic digestive diseases. In glomerulonephritis, pathological MDA levels (36%), but not PLA2 levels, were found. Serum MDA correlated with gamma-glutamyl transpeptidase (GGT), while PLA2 correlated with alanine-phosphodiesterase (ALP), GGT, alanine-aminotransferase (ALT) and creatinine. In urine, MDA and PLA2 behaved differently from the corresponding serum values. MDA increased in some patients with pancreatic cancer, extra-pancreatic diseases and glomerulonephritis. PLA2 levels did not significantly vary between groups. Urinary MDA correlated with some indicators of renal tubular damage [urinary ribonuclease, beta-2-microglobulin (B-2-M) and N-acetyl-glucosaminidase (NGA)] and with serum bilirubin. Urinary PLA2 correlated only with ribonuclease (RNase). We conclude that serum MDA increases aspecifically in pancreatic and extra-pancreatic diseases, probably reflecting an aspecific phlogistic phenomenon; PLA2, although sharing a similar pattern with MDA, seems mainly related to hepato-biliary damage. Urinary MDA reflects the presence of renal tubular damage, which may be the cause or a consequence of lipid peroxidation; little variations in PLA2 are recorded in urine, and mainly reflect the presence of impaired tubular function.

Adult↗

Does acetylsalicylic acid interfere with stimulated pancreatic secretion? An experimental study in the rat.

To evaluate the effect of the prostaglandin inhibitor acetylsalicylic acid (ASA) on rat exocrine pancreas secretion, three groups of rats were administered ASA by infusion: Groups 1-3, 50, 100, and 200 mg/kg body wt, respectively; Group 4 received saline. Twenty minutes later these ASA-pretreated groups were given intraarterial secretin (18 CU/kg) and cholecystokinin (CCK) (18 micrograms/kg). In an additional three groups of seven rats each, saline solution rather than secretin-CCK was given after ASA pretreatment. Pancreatic juice was collected every 10 min by means of a chronic pancreatic fistula. Bicarbonate and protein concentrations were measured and variations in outputs observed. No significant variations were found in the bicarbonate concentrations and outputs of rats with different types of pharmacological treatment, while protein concentrations and outputs were found to vary with time and type of experiment. There was, however, no interaction between these two variables. At lower ASA dosages, the bicarbonate and protein concentrations and outputs of secretin-CCK-stimulated rats were higher than the basal values and the levels of rats without hormonal stimulation. At higher dosages, no difference was found between the two groups. In conclusion, ASA seems to interfere with stimulated pancreatic exocrine secretion of proteins, even when its effect on bicarbonate concentration is factored in, and its effect seems to be present at the highest dosages considered in the study. Among the various hypotheses that may explain this phenomenon, an antagonizing effect of ASA on secretin-CCK action should be the first to be considered.

Animals↗

Alterations in bilirubin metabolism during extra- and intrahepatic cholestasis.

This study was performed to investigate modifications in the serum bilirubin forms, hepatobiliary enzymes, and some glycoproteic substances in patients during the course of extrahepatic cholestasis (stage A) and following its clinical resolution (stage B). The series consisted of 16 patients: 11 had main bile duct stones; two, benign stenosis of the main bile duct; and three, main bile duct cancer. Cholestasis resolved spontaneously in one case, under endoscopy in two, and following surgery in 13. Five patients with liver cirrhosis and a picture of intrahepatic cholestasis following anesthesia were also investigated. Serum bilirubin forms were measured using van den Bergh's method and the alkaline methanolysis-HPLC procedure; the mono- and di-conjugated forms were considered together in the overall evaluation of the results. The hepatobiliary enzymes (ALP, GGT, and AST) were increased at stage A and significantly decreased at stage B. Similar patterns were observed in total (TB), unconjugated (UB), and conjugated bilirubin (CB) and in the percentage of CB out of TB (% CB). In the majority of patients, % CB at stage B was lower than at stage A, whereas in subjects with a high initial UB value, a different % CB pattern was observed. The direct bilirubin percentage (% DB), on the other hand, had a different pattern, and the variations between stages A and B were not significant. The pathophysiological bilirubin pattern was similar in patients with intrahepatic cholestasis. At stage A, in a number of patients the levels of glycoproteic substances (CA 19-9, TPA and ferritin) were raised, but at stage B they tended to decrease towards the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗