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P Puig

Publications and source records attributed to P Puig.

At least 19 recordsLinked to original sources

Suitability of FISH painting techniques for the detection of partial-body irradiations for biological dosimetry.

Peripheral blood was irradiated with 2, 3, 4 or 5 Gy of X rays and was mixed with nonirradiated blood at five different dilutions to simulate partial-body irradiations. Analysis by FISH was performed using whole-chromosome painting probes for chromosomes 1, 4 and 11 in combination with a pancentromeric probe. Chromosome aberrations affecting the painted fraction were classified according to the PAINT nomenclature; other unstable aberrations affecting the unpainted material were also recorded. To evaluate the suitability of painting for dose assessment in partial-body irradiations, the ability of the u test and a proposed s test to detect the expected overdispersion and the similarity between the real doses and the doses estimated using Dolphin's approach were considered. For short-term biodosimetry, compared with solid-stained dicentric analyses, the suitability of FISH painting techniques for the detection of partial-body exposures is reduced, because of the decrease in the frequency of aberrations detected by FISH and in the number of cells with two or more aberrations. For reconstruction of past doses, when only complete apparently simple translocations in cells free of unstable aberrations were considered, the detection of the overdispersion and the accuracy of dose estimations were dramatically reduced. In a partial-body exposure, as the original dose increased, the whole-body dose estimated a long time after irradiation would tend to be lower, and the difference from the original dose would tend to be greater.

Adult↗

Clinical usefulness of K-ras gene mutation detection and cytology in pancreatic juice in the diagnosis and screening of pancreatic cancer.

BACKGROUND: The significance of K-ras codon 12 mutation in pancreatic juice is still unclear. Although considerable controversy surrounds this question, the diagnostic utility of K-ras in patients with clinical suspicion of pancreatic cancer (PC) and in PC-risk patients remains unknown. OBJECTIVE: To study prospectively the utility of the K-ras gene mutation and cytology in the diagnosis and screening of PC, and to assess its contribution to clinical decision making. METHODS: Pancreatic juice samples obtained from 90 patients were evaluated prospectively. Group I (n = 40) comprised patients with clinical suspicion of PC; group II (n = 50) comprised 49 patients with chronic pancreatitis and one patient proceeding from a PC family screening. The K-ras mutation was detected by means of artificial restriction fragment length polymorphisms (RFLP) in DNA after polymerase chain reaction (PCR) amplification. RESULTS: In group I, of those patients with a definitive diagnosis of PC, malignant cells were found in 27% and K-ras mutation in 44%. In five cases, molecular analysis contributed to diagnosis (4/11 with negative cytology and 1/2 with insufficient cytological material). K-ras mutation revealed an early tumour in one patient, and was the only sample available for diagnosis in another. In group II, the K-ras gene mutation was detected in 8/49 patients (16%) with chronic pancreatitis, one of whom developed PC (2%). CONCLUSIONS: K-ras mutation analysis of pancreatic juice may complement cytological evaluation in the diagnosis of PC, in spite of its limited contribution to clinical decision making. The presence of K-ras mutation in chronic pancreatitis classifies a subgroup of PC-risk patients who should be evaluated carefully by long-term follow-up.

Adult↗

A highly sensitive method for K-ras mutation detection is useful in diagnosis of gastrointestinal cancer.

Detection of molecular features such as K-ras mutations has been used to evaluate potential tumour markers in a wide variety of clinical samples. Here we have applied a recently developed highly sensitive method for detection of K-ras codon 12 mutations to colorectal and pancreatic cancer diagnosis. We analysed 67 faecal samples from patients undergoing diagnostic colonoscopy under suspicion of colorectal cancer. PCR products were obtained in 62 of 67 (93%) faecal samples. Mutations were detected in exfoliated cells in 6 of 22 (27%) of the adenomas and in 6 of 11 (55%) of adenocarcinomas. No false positives were observed. Agreement between faecal samples and corresponding tissues was 100% for adenocarcinomas and 65% for adenomas. Mutations were also analysed in 61 pancreatic fine-needle aspirates. Mutations were detected in 36 of 45 (80%) of the pancreatic aspirates diagnosed as pancreatic cancer without false positives. Our findings suggest that, when colorectal cancer is suspected, detection of K-ras codon 12 mutations in faecal samples using this new method is specific for colorectal tumours. Additionally, this technique is a good alternative for evaluation of pancreatic masses.

Adenocarcinoma↗

Prospective evaluation of the contribution of K-ras mutational analysis and CA 19.9 measurement to cytological diagnosis in patients with clinical suspicion of pancreatic cancer.

The aim of this study was to prospectively evaluate the diagnostic contribution of the detection of K-ras mutation and measurement of serum CA 19.9 concentrations to cytological diagnosis in patients with clinical suspicion of pancreatic cancer. These patients had either the presence or absence of a pancreatic mass as determined by imaging procedures. A total of 156 consecutive patients with clinical suspicion of pancreatic cancer or for confirmation and follow-up of their chronic pancreatitis disease were included: 84 patients presenting a pancreatic mass (group 1) and 72 patients without a pancreatic mass (group 2). K-ras mutations were detected by a restriction fragment length polymorphism/polymerase chain reaction (RFLP/PCR) method and CA 19.9 by an immunoluminometric assay. When a pancreatic mass was present, cytology offered a high sensitivity, but with a significant number of inconclusive results and K-ras mutational analysis offered a highly specific test. In the absence of a pancreatic mass, CA 19.9 (cut-off 100 U/ml) increased the sensitivity of the diagnosis by cytology and K-ras mutational analysis did not add significant information. Thus both tests contribute to the clinical decision process when pancreatic cancer is clinically suspected and the cytological report is not conclusive.

Adult↗

K-ras mutations in DNA extracted from the plasma of patients with pancreatic carcinoma: diagnostic utility and prognostic significance.

PURPOSE: Previous studies have demonstrated the presence of K-ras mutations in the plasma of patients with pancreatic carcinoma. However, the diagnostic utility and the prognostic significance of this finding have never been addressed. PATIENTS AND METHODS: Forty-four consecutive patients with histologically confirmed primary pancreatic ductal adenocarcinoma were included. A control group of 37 patients with chronic pancreatitis, 10 patients with other tumors of the pancreatic area, nine patients with acute pancreatitis, and four healthy volunteers was also included. Plasma DNA was isolated and K-ras codon-12 mutations were analyzed by means of restriction fragment length polymorphism-polymerase chain reaction and single-strand conformation polymorphism techniques. Patients were followed up to establish their clinical outcome. RESULTS: The mutant-type K-ras gene was found in plasma DNA samples of 12 (27%) of 44 patients with pancreatic ductal adenocarcinoma; this finding was related to the tumor stage (P = .05), mainly in the presence of distant metastases (P = .02). In addition, K-ras mutations were detected in the plasma DNA of two (5%) of 37 patients with chronic pancreatitis. In the subset of patients with pancreatic masses, the sensitivity and specificity of plasma K-ras analysis for pancreatic adenocarcinoma were 27% and 100%, respectively. Finally, pancreatic carcinoma patients with the mutant-type K-ras gene in plasma DNA exhibited a shorter survival time than patients with the wild-type gene (P<.005), and plasma K-ras mutations were identified as the only independent prognostic factor (odds ratio, 1.51; 95% confidence interval, 1.02 to 2.23). CONCLUSION: Plasma K-ras analysis is a highly specific, low-sensitivity approach that has diagnostic and prognostic clinical implications in patients with pancreatic carcinoma.

Adenocarcinoma↗

K-ras gene mutations in the diagnosis of fine-needle aspirates of pancreatic masses: prospective study using two techniques with different detection limits.

Detection of K-ras mutations may be useful in the evaluation of pancreatic cancer. The aim of this study was to assess, in a prospective design, the diagnostic utility of K-ras mutation analysis in 62 consecutive fine-needle aspirates of pancreatic masses, using two PCR-based techniques-standard and enriched-with detection limits of a mutant allele in the presence of 10(2) or 10(3) wild-type alleles, respectively. Cytology alone offered a diagnostic sensitivity of 75%. The enriched higher sensitivity detection technique, in combination with cytology, offered a diagnostic sensitivity of 91% without false positives. The molecular analysis would have contributed to diagnosis in an additional 14 cases of pancreatic cancer. The standard technique contributed to diagnosis in an additional 9 cases. These results strongly support the use of the enriched method of detecting K-ras mutations as a complement to cytology in the evaluation of pancreatic masses.

Aged↗

Child cerebrospinal fluid analysis by capillary electrophoresis and laser-induced fluorescence detection.

Capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) was used to analyze a 50-microliters sample of cerebrospinal fluid from leukaemic children treated with high doses of methotrexate. Free amino acids and primary amines are labelled with fluorescein isothiocyanate prior to analysis. Electropherograms containing more than 50 peaks were obtained in less than 22 min. Twenty-one peaks were identified, and 19 were quantitated. Observed differences in individual amino acid levels are compared with healthy reference values. The results indicate that CE-LIF is useful as a selective, rapid and sensitive tool for the determination of free amino acids and amines in clinical biology studies.

Adolescent↗

In vitro influence of molybdenum on benzo[a]pyrene metabolism in hepatic and pulmonary rat microsomes.

Our study presents the in vitro molybdenum influence on benzo[a]pyrene (BaP) microsomal metabolism. Addition of various concentrations of different molybdenum salts [MoS2, MoCl5, (NH4)6Mo7O24 . 4H2O] to liver and lung microsomal fractions of rats previously treated with 3-methylcholanthrene produces a decrease in the different BaP metabolites assessed by high-performance liquid chromatography (HPLC) analysis. This inhibition varies, depending on the considered metabolite and in relation to both the molybdenum level and the origin of the microsomal suspension. The minimum effective concentration is 0.26 and 0.52 mM Mo from liver and lung, respectively. The inhibitory potencies of the +5 (chloride) and +6 (ammonium heptamolybdate) molybdenum compounds are comparable; that of the sulfide is lower.

Animals↗

Derivatives of Co(II), Co(III), Ni(II), Cu(II), and Zn(II) with 5' AMP. Use as enzymatic labels with glycogen phosphorylase B.

Some new derivatives of Co(II), Co(III), Ni(II), Cu(II), and Zn(II) with 5' AMP have been obtained, characterized by elemental analysis, infrared, electronic, and fluorescence spectroscopy. The activities of these complexes as substitutes of 5' AMP as allosteric activators of glycogen phosphorylase b have been tested. The derivatives that have no interaction with the phosphate group are good analogs of the natural allosteric activator; the complexes that have direct bonding between metallic ion and phosphate groups do not activate the enzyme.

Animals↗

Catheter sepsis due to Staphylococcus epidermidis during parenteral nutrition.

Staphylococcus epidermidis is a pathogenic organism with increasing importance in total parenteral nutrition therapy. Strict asepsis during catheter insertion prolongs the interval free from Staphylococcus epidermidis infection. Staphylococcus epidermidis colonizes the catheter after migrating from the skin. For protection, we advise a long subcutaneous tunnel for all catheters that are to be indwelling for longer than three weeks. Prompt recatheterization of a patient with Staphylococcus epidermidis sepsis can result in hematogenous seeding of the new catheter and persistence of the infection. Catheter related Staphylococcus epidermidis sepsis has subsided after catheter withdrawal, and there is no need for antibiotic therapy provided that other prosthetic materials are not placed in the vascular tree. Immunologic status of the patients is not related to the frequency or severity of Staphylococcus epidermidis infections, or both.

Adult↗

Carcinoid tumors of the pancreas: CT findings.

Computed tomographic (CT) and ultrasound (US) findings in four cases of carcinoid tumors of the pancreas are reported. Differential diagnosis with other endocrine and nonendocrine pancreatic tumors is discussed. CT and US techniques play an important role in diagnosis, prognosis, and treatment of these tumors.

Adult↗