Biomedical subjects

Christian Jacquelinet

Publications and source records attributed to Christian Jacquelinet.

17 recordsLinked to original sources

PubMed2006

Molecular adsorbent recirculating system dialysis in patients with acute liver failure who are assessed for liver transplantation.

OBJECTIVE: To assess the usefulness of dialysis with the molecular adsorbent recirculating system (MARS) in patients with acute liver failure who fulfil criteria for liver transplantation. DESIGN: Observational cohort study. SETTING: ICU at a liver transplantation centre. PATIENTS: Twenty-two patients (23 episodes) received MARS dialysis. They were either listed for LT (n=14), delayed (n=1), or not listed (contra-indication, n=7). INTERVENTIONS: A total of 56 MARS treatments (median per patient 2; mean duration 7.6+/-2.6h) were performed on haemodialysis. MEASUREMENTS AND RESULTS: Clinical and biological variables were assessed before and 24[Symbol: see text]h after MARS therapy. The rate of recovery of liver function without transplantation was compared with an expected rate and survival was analysed. Following MARS dialysis, we observed an improvement in the grade of hepatic encephalopathy (P=0.02) and the Glasgow coma score (P=0.02), a decrease in conjugated bilirubin (P=0.05) and INR (P=0.006), and an increase in prothrombin index (P=0.005). Overall, liver function improved in seven patients (32%): four listed patients in whom transplantation could be avoided and three patients among those not listed due to contra-indications. The transplant-free recovery rate in listed patients was 29% (vs. expected 9%, P=0.036). Listed patients (n=14) had a higher 30-day survival rate [86% (12/14) vs 38% (3/8), P=0.05] and a higher long-term survival rate (P=0.02). CONCLUSIONS: A statistically significant improvement of liver function was observed after MARS therapy. Transplant-free recovery was more frequent than expected. The apparent benefit of MARS dialysis to treat acute liver failure needs to be confirmed by a controlled study.

Adult↗

PubMed2005

The renal epidemiology and information network (REIN): a new registry for end-stage renal disease in France.

The French Renal Epidemiology and Information Network (REIN) registry began in 2002 to provide a tool for public health decision support, evaluation and research related to renal replacement therapies (RRT) for end-stage renal disease (ESRD). It relies on a network of nephrologists, epidemiologists, patients and public health representatives, coordinated regionally and nationally. Continuous registration covers all dialysis and transplanted patients. In 2003, 2070 patients started RRT, 7854 were on dialysis and 7294 lived with a functioning graft in seven regions (with a population of 16.5 million people). The overall crude annual incidence rate of RRT for ESRD was 123 per million population (p.m.p.) with significant differences in age-adjusted rates across regions, from 84 [95% confidence interval (CI): 74-94] to 155 [138-172] p.m.p. The principal causes of ESRD were hypertension (21%) and diabetic (20%) nephropathies. Initial treatment for ESRD was peritoneal dialysis for 15% of patients and a pre-emptive graft for 3%. The one-year survival rate was 81% [79-83] in the cohort of 2002-2003 incident patients. As of December 31, 2003, the overall crude prevalence was 898 [884-913] p.m.p, with 5% of patients receiving peritoneal dialysis, 47% on haemodialysis and 48% with a functioning graft. The experience in these seven regions over these two years clearly shows the feasibility of the REIN registry, which is progressively expanding to cover the entire country.

Adolescent↗

PubMed2005

[Choosing between peritoneal dialysis and haemodialysis: a critical appraisal of the literature].

In France, incidence and prevalence of end-stage renal disease (ESRD) are increasing, requiring a more rational use of available replacement therapies. To help practitioners make their choice between treatment modalities of peritoneal dialysis (PD) and haemodialysis (HD), critical appraisal of relevant literature has been conducted. Although few absolute or relative contraindications for PD and HD exist, arguments in favour of one versus the other dialysis technique can be made. When patients receive adequate and complete information, their preference is neutral between PD and HD. To date, no trial presenting a convincing level of evidence has been published which demonstrates the superiority of one technique compared to the other. Relative to mortality, it appears that no difference can be observed between the two modalities. However, in those instances where patients expect a rapid transplantation, PD is the preferred technique. This analysis suggests that peritoneal dialysis and haemodialysis are not competitive but rather complementary treatments. It is therefore interesting to identify the reasons supporting the various choices between the two different treatment modalities amongst France's regions. Access to transplant, economic or organizational factors must be considered.

Contraindications↗

PubMed2005

[The new French rules for the attribution of renal transplants].

The French rules for the attribution of a kidney transplant are regularly evaluated and modified according to scientific progress, evolution of the waiting list and of health policies. Modifications, initiated by the Transplantation Commission of the French-speaking Society of Nephrology, have been introduced in 2004 by the Etablissement français des Greffes and aim at decreasing the number of patients on the waiting list having difficult access to transplantation because of their immunogenetic characteristics (rare ABO or HLA group, HLA immunization). Four points are concerned: 1/ better definition of hyperimmunisation; 2/ introduction of a program based on "acceptable mismatches" as a new priority for hyperimmunized patients; 3/ suppression of the full-match priority to non-immunized patients; 4/ attribution to immunized patients (anti-HLA antibodies=5-80%) who have difficult access to a transplant, of priorities similar to those followed for hyperimmunized patients. This article presents the new rules for the allocation of a kidney transplant and the rationale for the current modifications.

France↗

PubMed2005

New drugs for colorectal cancer (irinotecan, oxaliplatin, raltitrexed) meet expectations in routine practice: a single center's experience before and after their introduction.

BACKGROUND AND AIMS: Treatment of metastatic colorectal cancer with new drugs (NDs) as oxaliplatin and irinotecan had improved response and survival. In order to check whether the promising achievements of the trials are obtained in routine clinical practice, we have reviewed retrospectively our results for two periods, before (period A: 1993-1995, n=63) and after (period B:1998-2000 n=103) the introduction of these NDs. Patients characteristics, treatment modalities, survival, and prognostic factors were compared. PATIENTS: There were 74 women and 92 men, aged 60.8+/-11.6 yr, 7 patients received best supportive care only, 91 had synchronous metastasis. RESULTS: Period B patients were older, with WHO score>1 more often, more adjuvant treatment, more metachronous metastasis, and NDs used more frequently (24% vs 59%). Median survival was similar (16 vs 15 mo). But when looking at the population aged<75 years with WHO score<2, median survival was 13 mo (period A) vs 21 mo (period B); survival at 1, 2, and 3 yr were respectively 59.5+/-8%, 16.2+/-6 %, 13.5+/-6 % vs 69.8+/-6%, 49.6+/-7%, 29.8+/-7%, p<0.01). In multiparametric analysis, factors correlated with survival were the absence of elevated serum alkaline phosphatase, a unique metastatic organ, and administration of NDs. CONCLUSION: In our routine clinical experience the use of NDs for metastatic CRC has allowed a significant improvement in survival among patients with unresectable tumors.

Age Factors↗

PubMed2005

The French organ transplant data system.

The Agence de la Biomédecine is a state agency dealing with Public Health issues related, among others, to organ, tissue and cell transplantation in France. The Agence maintains a national information system used to coordinate and administer organ procurement and transplant activities and to perform the evaluation of organ transplantation activities. This paper describes the core uses and functional requirements of Cristal, the donor, recipient and allocation software of the information system and its evolution in the new system.

France↗

PubMed2005

Issues in the classification of disease instances with ontologies.

Ontologies define classes of entities and their interrelations. They are used to organize data according to a theory of the domain. Towards that end, ontologies provide class definitions (i.e., the necessary and sufficient conditions for defining class membership). In medical ontologies, it is often difficult to establish such definitions for diseases. We use three examples (anemia, leukemia and schizophrenia) to illustrate the limitations of ontologies as classification resources. We show that eligibility criteria are often more useful than the Aristotelian definitions traditionally used in ontologies. Examples of eligibility criteria for diseases include complex predicates such as ' x is an instance of the class C when at least n criteria among m are verified' and 'symptoms must last at least one month if not treated, but less than one month, if effectively treated'. References to normality and abnormality are often found in disease definitions, but the operational definition of these references (i.e., the statistical and contextual information necessary to define them) is rarely provided. We conclude that knowledge bases that include probabilistic and statistical knowledge as well as rule-based criteria are more useful than Aristotelian definitions for representing the predicates defined by necessary and sufficient conditions. Rich knowledge bases are needed to clarify the relations between individuals and classes in various studies and applications. However, as ontologies represent relations among classes, they can play a supporting role in disease classification services built primarily on knowledge bases.

Humans↗

PubMed2004

Living with a functioning kidney transplant at 74 yr or older: a national epidemiological study.

The number of older patients living with a functioning kidney graft is increasing. However the safety of the immunosuppressive treatment and quality of life in this population have not yet been determined. All patients grafted in France since 1969, born before the January 1 1926 and living with a functioning graft on January 1 2000 were included in this national study including all 34 French transplant centers. Renal function, immunosuppressive treatment, comorbid conditions and quality of life were assessed. From the initial population of 446 patients, 113 (26.2%) were still alive in 2000 (study population). Mean age was 76 yr (range: 74-80) with a mean post-transplant follow-up of 9.9 yr (0.1-28.7). Average serum creatinine level was 129 micromol/L (55-286). Immunosuppression was heterogeneous and included triple therapy (18.6%), dual therapy (41.6%) and monotherapy (40.8%). A history of cancer was noted in 36 of the 113 patients (32.1%) whereas hypertension was the most frequent co-morbid condition (80.3%). Estimated quality of life using the Karnofsky scale was between 80 and 100 in 78.4% of the patients. The immunosuppressive regimen in older renal transplant recipients living with a functioning graft varied widely among the 34 French transplant centers. Renal function in this group of patients was good and quality of life seemed excellent. Cardiovascular disease and malignancies were the main co-morbid conditions.

Aged↗

PubMed2004

A surgeon can operate or approach a complicated integral calculus instead of a renal one: implications for conceptual and lexical semantic disambiguation.

This paper approaches lexical semantic disambiguation and polysemy in the context of medical language understanding. These issues have been addressed as linguistic and cognitive requirements to build a knowledge extraction tool that turns natural language input into conceptual graphs. Previous results obtained with semantic analysis of medical terms in the domain of transplantation and organ failure prompt us to check the capabilities of our prototype to deal with ambiguities and polysemy. Starting from linguistic observation, we attempt to demonstrate how the respect of ambiguities when the co-text is not sufficient for disambiguation implies to introduce a void type in the concept type lattice. Then we show how the "creative use of words" (i.e. new senses in novel context) imposes to dynamically allocate type, categories and roles with the co-text.

Linguistics↗

PubMed2004

Evolving from standard vocabularies to formal ontology for an information system dedicated to organ transplantation.

Semantic heterogeneity is a key issue in the deployment of medical applications. In this paper, we examine solutions to address semantic heterogeneity for a complex organ transplantation information system. The information system that has been developed by the French agency for transplantation (EfG) has to gather medical information concerning patients and donors for organ allocation, epidemiological studies, and public health decisions. We analyze in this context the limits of the traditional approach based on a standard vocabulary and a relational database for the transplantation domain. We present its evolution towards a system that combines a terminology server and a data warehouse. The perspective is now to build a formal ontology that may support semantic integration in an advanced transplantation information system. Two open issues in formal ontology design are discussed. First, providing definitions of all medical concepts is not an obvious task if we want those definitions be meaningful, formal, and compatible with other ontologies. Second, propagation of properties along relations raises the needs for extending description logics with rules.

France↗

PubMed2003

Developing the ontological foundations of a terminological system for end-stage diseases, organ failure, dialysis and transplantation.

The Etablissement français des Greffes (EfG) is a state agency dealing with Public Health issues related to organ, tissue and cell transplantation in France. The evaluation of organ retrieval and transplantation activities, one of its missions, is supported by a national information system (EfG-IS). The EfG-IS is moving towards a new n-tier architecture comprising a terminology server for end-stage diseases, organ failure, dialysis and transplantation (EfG-TS). Following a preliminary audit of the existing coding system and in order to facilitate data recording, to improve the quality of information, to assume compatibility with terminological existing standards and to allow semantic interoperability with other local, national or international registries, a specific work has been conducted on the thesauri to integrate within the EfG-TS. In this paper focusing on the server's content rather than the container, we report first the functional and cognitive requirements that resulted from the preliminary audit. We then describe the methodological approach used to build the terminological server on "sound ontological foundations". We performed the semantic analysis of existing medical terms to set up disease description frame-like structures. These diseases description frames consist of a limited set of nosological discriminating slots such as etiology, semiology, pathology, evolution and associated diseases. Each relevant medical term is thus associated to a concept defined and inserted within a hierarchy according to disease description frame resulting from the semantic analysis. Last, because this terminological server is shared by various transplant and dialysis centers to record patient data at different time point, contextualization of terms appeared as one of the functional requirements. We will also point out various contexts for medical terms and how they have been taken into account.

Automation↗

PubMed2003

High rate of long-term virological response after a 1-year course of interferon +/- ribavirin in chronic hepatitis C relapsers. Results of a 191 patients randomized trial.

UNLABELLED: We investigated the long-term efficacy of a 12-month course of interferon (IFN)+ribavirin in chronic hepatitis C relapsers. We randomized 191 relapsers with a 2:1 ratio to receive 3 million units three times a week of interferon alpha (IFN alpha)-2b+ribavirin (1-1.2 g/day) (group A=127 patients) or IFN alpha-2b (group B=60 patients) of same dosage and duration for 1 year. General and hepatitis C data of group A and B patients were similar. The main goal of the study was to determine the rate of sustained virological response evaluated 1 year after treatment. RESULTS: Virological sustained response (SR) was 61% and 12% for groups A and B, respectively (P<0.001). A significant histological improvement was observed in both treatment groups. The Metavir activity score became significantly lower in the IFN+ribavirin group than in the IFN group (P<0/0001). The Metavir fibrosis scores remained unchanged. Also, at the end of the treatment, the virological response was 69% (88/127) for group A and 33% (20/60) for group B (P<0.001). CONCLUSION: One-year retreatment of relapsers with the combination of IFN+ribavirin led to 61% of virological SR and to a significant improvement of histological activity. Therefore, the therapeutic schedule presented here can be considered of particular interest for the retreatment of relapsers.

Administration, Oral↗

PubMed2003

A dynamic Web application within an n-tier architecture: a Multi-Source Information System for end-stage renal disease.

A Multi-Source Information System (MSIS) has been designed for the Renal Epidemiology and Information Network (REIN) dedicated to End-Stage Renal Disease. Interoperability has been considered at 4 levels: semantics, network, formats and contents. An n-tier architecture has been chosen at the network level. It is made out of a universal client, a dynamic Web server connected to a production database and to a data warehouse. The MSIS is patient-oriented, based on a regional organization. Its implementation in the context of a regional experimentation is presented with insights on the design and underlying technologies. The n-tier architecture is a robust model and flexible enough to aggregate multiple information sources and integrate modular developments. The data warehouse is dedicated to support health care decision-making.

Data Display↗

PubMed2003

A contextual coding system for transplantation and end stage diseases.

The Establissement français des Greffes (EfG) is a state agency dealing with Public Health issues related to organ, tissue and cell transplantation in France. EfG maintains a national information system (EfG-IS) for the evaluation of organ transplantation activities. The EfG-IS is moving toward a new n-tier architecture comprising a terminological server. Because this terminological server is shared by various kind of transplant teams and dialysis centers to record patients data at different time point, contextualisation of terms appeared as a functional requirement. We report in this paper various contexts for medical terms and how they have been taken into account.

Cell Transplantation↗

PubMed2002

[SIMS REIN: a multi-source information system for end-stage renal disease].

In France, the prevalence of End-Stage Renal Disease (ESRD) is not precisely known. The sources of information are scattered and not coordinated. Consequently, care is ill adapted to meet the demand. The Multi-Source Information System is the basis of the Renal Epidemiology and Information Network (REIN). It is dedicated to improve and organise our medical and epidemiological knowledge of ESRD and to aid public health decision-making in this area. The proposed approach is based on the datawarehouses. This model allows a unified vision of scattered data into distinct databases, for a better management, be it particular (patient follow-up) or global (regional follow-up), with a finality of aid in decision-making. Several categories of problems were considered: the global conception of the information system, the organisation of the datawarehouse, which offers different viewpoints of the data, the integration of heterogeneous data coming from different sources, data exchange and definition of a specific ontology.

Computer Communication Networks↗

PubMed2002

[Regional differences in the access to liver transplantation in France].

AIM: This study evaluated regional differences in registration on the waiting list and access to liver transplantation in France. METHODS: The annual incidence of registration on the waiting list was calculated with the number of transplantation candidates registered in each region between 1996 and 1998 and was used as an indicator for access to the waiting list. The median waiting time before receiving a graft was estimated for patients registered between 1992 and 1998 by the Kaplan Meier method using transplantation as the event. This was used as an indicator for access to transplantation. Shortage of liver grafts was based on the ratio between the number of registered patients and the number of transplantations. RESULTS: The national incidence rate on the liver transplantation waiting list was 11.5 candidates per million inhabitants (pmi). There were no significant statistical differences among regions but it was high for the Rhône-Alpes region (18.6 pmi) and low for the French West Indies (3.6 pmi). The median waiting time before a graft is 2.2 months, and varied from 0.5 month to 3.8 months in French regions (p<0.001). Lack of a graft was strongly correlated with the median waiting time but not with the harvested liver rate. CONCLUSION: Although there is no statistical significant difference in access to the waiting list for liver transplantations, access to grafts differs among the regions in France.

France↗

PubMed2002

Design considerations for an ontology in the domain of organ failure and transplantation.

The Etablissement français des Greffes (EfG) is a national agency dealing with Public Health issues related to organ, tissue and cell transplantation in France. The evaluation of organ retrieval and transplantation activities, one of its missions, is supported by a national information system (IS). In order to facilitate data recording, to improve the quality of information and to prepare semantic interoperability with other information systems, the existing thesaurus of the EfG was audited, leading to the design a new terminological module devoted to the support of the domain ontology.

France↗