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Patrick Rampal

Publications and source records attributed to Patrick Rampal.

16 recordsLinked to original sources
PubMed2003

Effects of fatty acids on the growth of Caco-2 cells.

Epidemiological studies suggest that polyunsaturated fatty acids may protect against colorectal neoplasia. In order to explore this observation, cell proliferation and viability, lipid composition, membrane fluidity, and lipid peroxidation were measured in Caco-2 cells after 48h incubation with various fatty acids. Saturated and monounsaturated fatty acids incorporated less well in the membranes than polyunsaturated fatty acids (PUFAs). All of the PUFAs tested had an inhibitory effect on cell proliferation/viability whereas the saturated and monounsaturated fatty acids did not. Addition of palmitic acid had no significant effect on membrane fluidity whereas unsaturated fatty acids increased membrane fluidity in a dose-dependent manner. PUFAs strongly increased tumor cell lipid peroxidation in a dose-dependent manner. Saturated and monounsaturated fatty acids increased lipid peroxidation in this cell line only at high concentration. Preincubation of Caco-2 cells with vitamin E prevented the inhibition of proliferation/viability, the elevation of the MDA concentration and the increased membrane fluidity induced by PUFAs. Our data indicate that PUFAs are potent inhibitors of the growth of colon cancer cells in vitro.

Apoptosis↗
PubMed2003

Assessing medical students' clinical sciences knowledge in France: a collaboration between the NBME and a consortium of French medical schools.

PURPOSE: The French government, as part of medical education reforms, has affirmed that an examination program for national residency selection will be implemented by 2004. The purpose of this study was to develop a French multiple-choice (MC) examination using the National Board of Medical Examiners' (NBME) expertise and materials. METHOD: The Evaluation Standardisée du Second Cycle (ESSC), a four-hour clinical sciences examination, was administered in January 2002 to 285 medical students at four university test sites in France. The ESSC had 200 translated and adapted MC items selected from the Comprehensive Clinical Sciences Examination (CCSE), an NBME subject test. RESULTS: Less than 10% of the ESSC items were rejected as inappropriate to French practice. Also, the distributions of ESSC item characteristics were similar to those reported with the CCSE. The ESSC also appeared to be very well targeted to examinees' proficiencies and yielded a reliability coefficient of.91. However, because of a higher word count, the ESSC did show evidence of speededness. Regarding overall performance, the mean proficiency estimate for French examinees was about 0.4 SD below that of a CCSE population. CONCLUSIONS: This study provides strong evidence for the usefulness of the model adopted in this first collaborative effort between the NBME and a consortium of French medical schools. Overall, the performance of French students was comparable to that of CCSE students, which was encouraging given the differences in motivation and the speeded nature of the French test. A second phase with the participation of larger numbers of French medical schools and students is being planned.

Clinical Medicine↗
PubMed2003

Saccharomyces boulardii interferes with enterohemorrhagic Escherichia coli-induced signaling pathways in T84 cells.

Enterohemorrhagic Escherichia coli (EHEC) infections are associated with the modification of tight-junction permeability and synthesis of proinflammatory cytokine interleukin-8 (IL-8). In a previous study, it was demonstrated that EHEC-induced IL-8 secretion is due to the involvement of the mitogen-activated protein kinase (MAPK), AP-1, and NF-kappaB pathways. In this study, we investigated the effect of the yeast Saccharomyces boulardii on EHEC infection in T84 cells. For this purpose, cells were (i) incubated with bacteria and yeast at the same time or (ii) incubated overnight with yeast cells that were maintained during infection or eliminated by several washes before infection. Coincubation is sufficient to maintain the transmonolayer electrical resistance (TER) of EHEC-infected cells, whereas the preincubation of cells with the yeast without elimination of the yeast during infection is necessary to significantly decrease IL-8 secretion. We thus analyzed the mechanisms of S. boulardii action. We showed that S. boulardii has no effect on EHEC growth or on EHEC adhesion. Kinetics studies revealed that EHEC-induced myosin light chain (MLC) phosphorylation precedes the decrease of TER. ML-7, an MLC kinase inhibitor, abolishes the EHEC-induced MLC phosphorylation and decrease of TER. Studies show that S. boulardii also abolishes EHEC-induced MLC phosphorylation. We demonstrated that the preincubation of cells with S. boulardii without washes before EHEC infection inhibits NF-kappaB DNA binding activity, phosphorylation and degradation of IkappaB-alpha, and activation of the three members of a MAPK group (extracellular signal-regulated protein kinases 1 and 2, p38, and c-jun N-terminal kinase). These findings demonstrate that S. boulardii exerts a preventive effect on EHEC infection by (i) interfering with one of the transduction pathways implicated in the control of tight-junction structure and (ii) decreasing IL-8 proinflammatory secretion via inhibition of the NF-kappaB and MAPK signaling pathways in infected T84 cells.

Bacterial Adhesion↗
PubMed2003

[Transposition of an American-designed comprehensive medical student examination within the framework of the forthcoming French nationwide comprehensive examination. A preliminary study].

Medical training is undergoing extensive revision in France. A nationwide comprehensive clinical competency examination will be administered for the first time in 2004, relying exclusively on essay-questions. Unfortunately, these questions have psychometric shortcomings, particularly their typically low reliability. High score reliability is mandatory in a high-stakes context. The National Board of Medical Examiners-designed multiple choice-questions (MCQ) are well adapted to assess clinical competency with a high reliability score. The purpose of this study was to test the hypothesis that French medical students could take an American-designed and French-adapted comprehensive clinical knowledge examination with this MCQ format. Two hundred and eighty five French students, from four Medical Schools across France, took an examination composed of 200 MCQs under standardized conditions. Their scores were compared with those of American students. This examination was found assess French students' clinical knowledge with a high level of reliability. French students' scores were slightly lower than those of American students, mostly due to a lack of familiarity with this particular item format, and a lower motivational level. Another study is being designed, with a larger group, to address some of the shortcomings of the initial study. If these preliminary results are replicated, the MCQ format might be a more defendable and sensible alternative to the proposed essay questions.

Adult↗
PubMed2002

Effect of age on substrate oxidation during total parenteral nutrition.

OBJECTIVE: Parenteral nutrition is increasingly used in the elderly. Aging is accompanied by metabolic changes that can modify substrate use. We compared substrate oxidation during cyclic total parenteral nutrition (TPN) in elderly and middle-aged patients. METHODS: Twelve elderly patients (eight women, four men; 72 +/- 5 y) and 12 middle-aged patients (nine women, three men; 39 +/- 13 y) who were on cyclic TPN for intestinal failure were investigated while in stable condition after at least 15 d of TPN. No patient was diabetic. Indirect calorimetry was performed during fasting and every 30 min during the 3 h of TPN infusion and 3 h after infusion, allowing the measurement of nutrient oxidation. Blood samples were obtained every hour for the measurement of glucose, insulin, triacylglycerols, and free fatty acids. RESULTS: In the fasting state, resting energy expenditure was significantly higher in the elderly patients than in the middle-aged patients (39.3 +/- 8.1 versus 31.9 +/- 4.3 kcal/kg of fat-free mass per day, P = 0.008). During TPN, lipid oxidation was significantly higher in the elderly patients than in the middle-aged patients (1.09 +/- 0.17 versus 0.84 +/- 0.27 mg x kg(-1) x min(-1), P = 0.011); glucose oxidation was significantly lower in the elderly patients than in the middle-aged patients (2.19 +/- 0.93 versus 3.22 +/- 1.54 mg x kg(-1) x min(-1), P = 0.038). Areas under the curves of glycemia and free fatty acids were significantly higher in the elderly patients. CONCLUSION: In the elderly, TPN was associated with significantly higher lipid oxidation and lower glucose oxidation than in younger patients. TPN formulas and flow rates should therefore be adapted in the elderly.

Adult↗
PubMed2002

Immunolocalization of a new intestinal antiproliferative factor in human intestinal epithelial cells.

A new intestinal antiproliferative factor (IAF) with an approximate molecular weight of 120 kDa has been purified from the human small intestine. This factor blocks the progression of human colon adenocarcinoma cells HT-29 from the G1 to the S phase. IAF, specific of the lower part of the digestive tract, was detected rather late in mouse embryonic development. For determination of the specific intestinal cell producing IAF, long-term differentiated mucus-secreting HT-29 Cl 16E and enterocytic HT-29 Cl 19A cell lines were used. IAF is synthesized exclusively in the intestinal goblet cells; it is processed in the RER and Golgi complex before being excreted in secretory vesicles independently of mucin secretion. IAF can be considered a growth inhibitor of intestinal proliferation for the same reason as TGF-beta. However, two features differentiate it from TGF-beta: (1) the intestinal cell type synthesizing it, and (2) the delay in its expression in embryonic development. Particular interest was paid to IAF expression in pathological conditions using human colon biopsies. IAF was consistently recovered in biopsies from patients with inflammatory bowel diseases and benign tumors, but it was never detected in malignant tumors. IAF could represent a marker of colon cancer owing to its absence from malignant tumors.

Adenocarcinoma↗
PubMed2002

Lack of adaptation to severe malnutrition in elderly patients.

BACKGROUND & AIMS: Sarcopenia is a common feature in the healthy elderly. However, little is known on age-related modifications of body composition in malnourished patients. The aims of this cross-sectional study were to evaluate the effects of aging per se on body composition and resting energy expenditure (REE) in malnourished patients. METHODS: Ninety-seven non-stressed patients referred for chronic malnutrition (C-reactive protein <5 mg/l) were separated into two groups: middle-aged (26 female, 19 male, 48+/-15 yr), and elderly (26 female, 26 male, 79+/-6 yr). Body composition was assessed by bioelectrical impedance analysis and REE by indirect calorimetry. RESULTS: In middle-aged patients, body composition remained stable between moderate (body-mass index [BMI; in kg/m(2)] 16-18.5) and severe (BMI < 16) malnutrition, with similar values of fat-free mass (FFM), body cell mass (BCM) and fat mass (FM) as percentages of body weight, whereas in elderly patients malnutrition occurred at the expense of FFM and BCM, with unchanged FM absolute values. REE/FFM values remained stable in middle-aged patients at every stage of malnutrition, whereas they increased in elderly patients along with their degree of malnutrition. In multivariate analysis, both body composition and REE/FFM were influenced by sex, age, BMI and mid-arm circumference. CONCLUSION: Compared to younger patients, weight loss in the elderly leads to cachexia, with a preferential loss of FFM and BCM that may participate in the more severe outcomes observed in these patients. They also show elevated REE/FFM values that induce higher energy needs.

Adaptation, Physiological↗
PubMed2002

Diagnostic accuracy of a rapid urine-screening test (Multistix8SG) in cirrhotic patients with spontaneous bacterial peritonitis.

OBJECTIVE: To assess the diagnostic accuracy of a rapid urine-screening test (Multistix8SG) for spontaneous bacterial peritonitis (SBP) in cirrhotic patients. METHODS: Seventy-two consecutive patients (44 males, 28 females; mean age 61.6 years) with cirrhosis and ascites were included in the study. A diagnostic paracentesis was performed on hospital admission in all patients and 2 days after antibiotic treatment in the case of SBP (polymorphonuclear [PMN] count over 250/mm in ascitic fluid). Each fresh sample of ascitic fluid was also tested using the Multistix8SG urine test, and the results were scored as negative, trace or positive. RESULTS: Nine of the 72 patients had SBP and the Multistix8SG urine test was positive. After 48 h of antibiotic therapy, the PMN count of three of these nine patients was still above 250/mm and the Multistix8SG test remained positive. In three other patients with SBP, the PMN count dropped below 250/mm and the Multistix8SG test result had become negative. Two of the nine SBP patients died before 48 h, and paracentesis was not performed in the ninth case. In the other 63 patients, the PMN count in ascitic fluid was below 250/mm; the Multistix8SG test revealed 17 trace results and 46 negative results. At the threshold of 250 PMN/mm in ascitic fluid, this test had a sensitivity and a specificity of 100%. CONCLUSION: A positive Multistix8SG urine test result in ascitic fluid appears to be an indication for antibiotic treatment.

Ascitic Fluid↗
PubMed2002

Effect of steroids on energy expenditure and substrate oxidation in women with Crohn's disease.

OBJECTIVE: Patients with Crohn's disease (CD) have increased energy expenditure and fat oxidation. Steroids, commonly used to treat flare-up of CD, induce weight gain. This study was designed to evaluate the effects of prednisone and budesonide on energy expenditure and substrate oxidation in patients with CD. METHODS: Twenty-nine women with CD and 10 healthy controls were studied. Ten patients received prednisone (0.75-1.0 mg/kg/day), nine received budesonide (9 mg/ day), and 10 did not receive steroids. Resting energy expenditure and substrate oxidation were measured by indirect calorimetry in a fasting state and after a standard diet. RESULTS: In the fasting state, resting energy expenditure was higher in patients without steroids than in the controls. Lipid oxidation was lower (p < 0.01) in patients with prednisone (0.46 +/- 0.39 mg/kg/min) than in patients with budesonide (0.97 +/- 0.28 mg/kg/min) and without steroids (1.06 +/- 0.32 mg/kg/min), but was similar with control subjects (0.47 +/- 0.20 mg/kg/min). Postprandially, lipid oxidation was lower (p < 0.01) in patients with prednisone (0.32 +/- 0.23 mg/kg/min) than in patients with budesonide (0.75 +/- 0.20 mg/kg/min), without steroids (0.82 +/- 0.23 mg/kg/min), and controls (0.58 +/- 0.15 mg/kg/min). Protein oxidation was significantly higher in patients with prednisone than in the other subjects. CONCLUSIONS: In women with CD, prednisone decreases lipid oxidation and increases protein oxidation. These effects are not observed with budesonide and may contribute to the weight gain and side effects commonly observed with prednisone. A low-fat/high-protein diet could be proposed during a course of prednisone.

Adult↗
PubMed2002

Enterohemorrhagic Escherichia coli infection induces interleukin-8 production via activation of mitogen-activated protein kinases and the transcription factors NF-kappaB and AP-1 in T84 cells.

Enterohemorrhagic Escherichia coli (EHEC) infections are associated with hemorrhagic colitis and the hemolytic-uremic syndrome (HUS). In vivo, elevated plasma levels of the proinflammatory cytokine interleukin-8 (IL-8) in EHEC-infected children are correlated with a high risk of developing HUS. As IL-8 gene transcription is regulated by the transcription factors NF-kappaB and AP-1, we analyzed the role of these factors in the regulation of IL-8 production after infection of the epithelial intestinal T84 cell line by EHEC. By 6 h of infection, EHEC had induced significant secretion of IL-8 (35.84 +/- 6.76 ng/ml versus 0.44 +/- 0.04 ng/ml in control cells). EHEC induced AP-1 and NF-kappaB activation by 3 h of infection. Moreover, the three mitogen-activated protein kinases (MAPK) (ERK1/2, p38, and JNK) were phosphorylated in EHEC-infected T84 cells concomitant with induction of AP-1 DNA binding activity, and IkappaB-alpha was phosphorylated and then degraded concomitant with induction of NF-kappaB DNA binding activity. Pretreatment of cells with the highly specific MEK1/2 inhibitor U0126, the p38 inhibitor SB203580, and/or the proteasome inhibitor ALLN led to inhibition of the IL-8 secretion induced in EHEC-infected T84 cells. These findings demonstrate that (i) EHEC can induce in vitro a potent proinflammatory response by secretion of IL-8 and (ii) the secretion of IL-8 is due to the involvement of MAPK, AP-1, and NF-kappaB signaling pathways.

Cell Line↗
PubMed2002

[Registry of liver biopsies from hepatitis C infected patients in the Alpes-Maritimes (France). Results from the first 2 years].

OBJECTIVE: To perform a descriptive analysis of patients with chronic hepatitis C based on a local registry of liver biopsies. PATIENTS AND METHOD: Collection of clinical, biological and histological data from all HCV-infected patients who underwent liver biopsy between January 1997 and December 1998 in the Alpes-Maritimes (France). RESULTS: One thousand and fifty six patients including 924 who lived in the Alpes-Maritimes (515 male, 409 female, mean age: 44.9 years old) were included. Intravenous drug use (30.1%) was the major suspected source of infection before blood transfusion (28.2%). Among intravenous drug users, 38% of patients were infected with genotype 1a and 37.4% with genotype 3. The METAVIR fibrosis severity score was distributed as follows: F0: 10.8%, F1: 53.7%, F2: 15.9%, F3: 14.7%, and F4: 4.9%. In a multivariate analysis adjusted for the duration of infection, independent risk factors associated with the severity of fibrosis were age at contamination >=30 years, genotype other than 1a and alcohol intake >=50 g/day. Determination of HCV antibody and liver biopsy were performed an average of 12.5 and 14 years after presumed date of contamination, respectively. CONCLUSIONS: These data provide a clearer view of the impact of this condition in this area and could help to define a comprehensive policy for patient management.

Adult↗