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O Chassany

Publications and source records attributed to O Chassany.

At least 37 records · Page 2Linked to original sources
PubMed1999

Ethics and clinical trials.

The current reference guideline about ethics in clinical trials is the Declaration of Helsinki of human rights in medical research. Three major principles are emphasised: respect of the patient to accept or not to participate in a trial, the constraints and the presumed risks must be acceptable for patients included in a study, and vulnerable subjects should not participate in studies. The investigator is responsible for obtaining a free and well-informed consent from patients before their inclusion in a study. Where possible, a new drug should always first be compared to placebo in order to prove its superiority. Else, a small-sized trial comparing a new drug versus a reference treatment can lead to an erroneous conclusion of absence of difference. Moreover, good results or improvement are obtained in at least 30% of cases with placebo, whatever the disease. The use of placebo is unethical in life-threatening diseases and when an effective proved drug exists. The use of placebo is ethical in severe diseases with no efficient drug, in some severe diseases even when an active reference treatment is available, and in all moderate and functional diseases. In order to detect flawed studies, most journals now ask for any manuscript submitted and reporting results of a randomised clinical trial to join a checklist in order to verify the quality of the trial. Finally, it remains the responsibility of the doctor to decide whether or not a protocol is ethical, to participate or not and to include patients or not.

Advertising↗
PubMed1999

Validation of a specific quality of life questionnaire for functional digestive disorders.

BACKGROUND: Dyspepsia and irritable bowel syndrome are suitable conditions for assessment of quality of life. Their similarities justify the elaboration of a single specific questionnaire for the two conditions. AIMS: To examine the process leading to the validation of the psychometric properties of the functional digestive disorders quality of life questionnaire (FDDQL). METHODS: Initially, the questionnaire was given to 154 patients, to assess its acceptability and reproducibility, analyse its content, and reduce the number of items. Its responsiveness was tested during two therapeutic trials which included 428 patients. The questionnaire has been translated into French, English, and German. The psychometric validation study was conducted in France, United Kingdom, and Germany by 187 practitioners. A total of 401 patients with dyspepsia or irritable bowel syndrome, defined by the Rome criteria, filled in the FDDQL and generic SF-36 questionnaires. RESULTS: The structure of the FDDQL scales was checked by factorial analysis. Its reliability was expressed by a Cronbach's alpha coefficient of 0.94. Assessment of its discriminant validity showed that the more severe the functional digestive disorders, the more impaired the quality of life (p<0.05). Concurrent validity was supported by the correlation found between the FDDQL and SF-36 questionnaire scales. The final version of the questionnaire contains 43 items belonging to eight domains. CONCLUSIONS: The properties of the FDDQL questionnaire, available in French, English, and German, make it appropriate for use in clinical trials designed to evaluate its responsiveness to treatment among patients with dyspepsia and irritable bowel syndrome.

Adult↗
PubMed1998

Quality of life in irritable bowel syndrome, effect of therapy.

BACKGROUND: Irritable bowel syndrome (IBS) is a common disease in the general population. Evaluation of IBS symptoms does not cover all the complaints of patients who report restrictions to social life, the need to diet and psychosocial repercussions. Quality of life (QOL) measurement permits a precise approach to patient status. METHODS: The generic QOL questionnaires SF 36 and two validated specific QOL questionnaires--IBSQOL and Functional Digestive Disorders FDDQL--have been used for the evaluation of IBS patient outcome. IBSQOL measures 9 domains and its reliability and validity have been demonstrated. FDDQL measures 8 domains, an international psychometric validation was obtained in French, English and German by comparison with the SF36. The discriminant validity and responsiveness of the FDDQL have been evaluated. RESULTS: Generic QOL evaluation and specific questionnaires like the FDDQL were able to measure changes in IBS patient status and QOL during several clinical trials. CONCLUSION: Specific QOL questionnaires have been validated in IBS patients and are available for controlled studies. Development of effective new drugs are needed for IBS treatment, complete and precise evaluation of outcome will involve QOL analysis in association with specific validated questionnaires.

Activities of Daily Living↗
PubMed1998

The role of quality of life in functional gastrointestinal disorders: regulatory issues.

Generic questionnaire such as SF36 and functional gastrointestinal disorder (FGD)-specific questionnaires (i.e. IBSQOL or FGDQL) are now available for the evaluation of new drugs for the treatment of irritable bowel syndrome or functional dyspepsia. For regulatory issues it is necessary to describe in detail the scale of the QOL questionnaire, its psychometric properties and reason for its choice, as well as validation studies, populations concerned, means of administration and methods for analysis. Preselection of few dimensions of the QOL questionnaire, if necessary, has to be explained. QOL results have to be compared with symptom scores. Trials have to be double-blind placebo- controlled studies with a sample size calculation taking account of the high placebo-response. No official guidelines are available in FGD and more validation studies are needed to help in the choice of the specific QOL questionnaire, in the metrologic analysis and in the interpretation of QOL changes during FGD treatment. Then QOL questionnaires could become a primary end point in clinical trials if efficient drugs for FGD treatment are developed.

Colonic Diseases, Functional↗
PubMed1996

[Treatment of viral hepatitis C].

Viral hepatitis C is a serious public health problem in France by the number of infected patients, the evolutive profile and by the lack of fully efficient therapeutics. However, the risk of developing cirrhosis and hepatocellular carcinoma may not be so high as it has been stated until now. Interferon alpha is at the present time, the only approved drug for the treatment of chronic hepatitis C. Its efficiency on criteria such as normalization of aminotransferases values or negativation of viremia is obtained in less than 25% of patients. The present recommendation is to use 3 MU of interferon alpha, 3 times per week during 12 months. While interferon leads to improvement of histologic lesions, it is not yet proved that a treatment by interferon can reduce, years after, the incidence of cirrhosis and hepatocellular carcinoma. No therapeutic strategy has been defined yet for the frequent situations of "no response", relapses or presence of factors that reduce the efficacy of treatment (high initial viremia level, genotype 1b, cirrhosis). It is possible that the course of patients having low or no elevation of aminotransferases and/or minimal histologic lesions, is good without any treatment. The efficacy of interferon alone appears insufficient. Thus trials in progress concern associations of antiviral drugs such as vidarabine. In lack of vaccine, preventive treatment is essential and depends upon knowledge of conditions of transmission of the virus. Transmission through blood and intravenous drug addiction represent 60 to 70% of cases of hepatitis C.

Alanine Transaminase↗
PubMed1996

Comparative serum protein binding of anthracycline derivatives.

The binding of doxorubicin, iododoxorubicin, daunorubicin, epirubicin, pirarubicin, zorubicin, aclarubicin, and mitoxantrone to 600 microM human serum albumin and 50 microM alpha 1-acid glycoprotein was studied by ultrafiltration at 37 degrees C and pH 7.4. Anthracycline concentrations (total and free) were determined by high-performance liquid chromatography (HPLC) with fluorometric detection. Binding to albumin (600 microM) varied from 61% (daunorubicin) to 94% (iododoxorubicin). The binding to alpha 1-acid glycoprotein (50 microM) was more variable, ranging from 31% (epirubicin) to 64% (zorubicin), and was essentially related to the hydrophobicity of the derivatives. Simulations showed that the total serum binding varied over a broad range from 71% (doxorubicin) to 96% (iododoxorubicin). We recently reported that the binding to lipoproteins of a series of eight anthracycline analogues could be ascribed to chemicophysical determinants of lipophilicity [2]. The present study was conducted to evaluate in vitro the contribution of albumin and alpha 1-acid glycoprotein to the total serum binding of these drugs.

Antibiotics, Antineoplastic↗
PubMed1995

Orocecal transit time in humans assessed by sulfapyridine appearance in saliva after sulfasalazine intake.

PURPOSE: We propose a noninvasive method for the measurement of orocecal transit time assessed by the sulfapyridine appearance time in saliva after ingestion of sulfasalazine. METHOD: In 12 healthy volunteers, we studied the correlation between plasma and saliva sulfapyridine appearance times and then the sulfapyridine appearance times in saliva under various experimental conditions to assess the reproducibility, the effects of meals, and the role of the formulation, and the effects of gastrointestinal kinetic drugs. RESULTS: The correlation between saliva and plasma sulfapyridine appearance times was strong (r = 0.84; p = 0.0004). The sulfapyridine saliva appearance time was significantly delayed by the meal. Compared with placebo, the saliva sulfapyridine appearance time was reduced by cisapride (312 +/- 128 versus 551 +/- 97 minutes; p = 0.0001) and increased by loperamide (674 +/- 267 versus 501 +/- 131 minutes; p = 0.044). CONCLUSION: We propose the salivary sample method as a validated simplification of the plasma sulfasalazine-sulfapyridine test for the measurement of orocecal transit time.

Adult↗
PubMed1995

[Therapeutic principles in gastroesophageal reflux].

Gastroesophageal reflux is a common disease. Its chronic course, even if mild, is sometimes complicated by erosive oesophagitis. Drug therapy acts against gastric acidity and motility disorders. Treatment of gastroesophageal reflux disease has three aims: improvement of symptoms and quality of life, healing erosive lesions and prevention of symptomatic and endoscopic relapses. Non-drug measures are always useful, even if their efficacy is not well established. Initial therapy of a symptomatic reflux or mild oesophagitis is most of the time effective (antacids, prokinetics, H2 receptor antagonists). Proton-pump inhibitors are also effective in healing and preventing severe oesophagitis. Questions about long-term treatment adverse events with powerful acid inhibitors, such as hypergastrinemia and the risk of gastric carcinoid tumours seem to be resolved. Studies are requested to define the optimal long-term maintenance treatment with cisapride, H2 receptor antagonists or proton-pump inhibitors at low doses in prevention of symptomatic and mild oesophagitis relapses.

Esophagitis, Peptic↗
PubMed1994

Analysis of free fatty acid effect on methotrexate binding to albumin.

The binding of methotrexate to human serum albumin and the inhibitory effect of serum free fatty acids (FFA) have been studied by equilibrium dialysis with radiolabeled methotrexate. Methotrexate was bound to albumin via a single site (1.03 +/- 0.02) with a low affinity (1350 +/- 60 M-1). The effect of FFA on binding by albumin of methotrexate was analysed according to the classical inhibition models with computation of the free inhibitor concentration and was ascribed to an uncompetitive type of inhibition. These results were in agreement with the observed serum binding of methotrexate (45-50%) and allowed the simulation of the effect of various concentrations of FFA on methotrexate albumin binding in human serum.

Binding, Competitive↗