Biomedical subjects

B Dufour

Publications and source records attributed to B Dufour.

At least 19 recordsLinked to original sources

PubMed2006

[The design and establishment of epidemiological surveillance systems for high-risk diseases in developed countries].

In animal pathology, epidemiological surveillance has, over the last two decades, gradually become a top priority in developed countries, due to progress made in fighting major animal diseases. The management of effective epidemiological surveillance networks for high-risk animal diseases in developed countries is based on general rules governing epidemiological surveillance networks, but involves certain specificities. This article first of all sets out the requirements for the optimal functioning of epidemiological surveillance networks. It then describes and analyses the qualities expected of high-risk animal disease surveillance networks: detection sensitivity and specificity, simplicity and adaptability, and good cost efficiency. Finally, it illustrates these general concepts via four examples of animal disease epidemiological surveillance in developed countries: foot and mouth disease in Europe, West Nile virus in the United States of America and France, and bluetongue in France.

Animal Diseases↗

PubMed2006

The organisation and functioning of Veterinary Services: results of a 2005 survey of Member Countries of the World Organisation for Animal Health.

A questionnaire was sent to the 167 Member Countries of the World Organisation for Animal Health (OIE) in 2004 and 2005. The organisation and functioning of national Veterinary Services were analysed based on the responses from 85 of these countries. Leaving aside variations between countries, Veterinary Services are very involved in animal health and food safety controls at farm level (including animal feed), and during primary and secondary processing, whether alone or in conjunction with other services. At the lower end of the chain, namely distribution and the food service industry, responsibilities tend to be more widely shared. Veterinary Services have a central responsibility in international trade in animals and animal products. The main weaknesses in the chain of controls concern the logistical and financial resources of Veterinary Services, and insufficient involvement of livestock producers and even of field veterinarians. The many recent reforms are tending to provide a more consistent, integrated approach to animal health and food safety controls 'from the stable to the table'.

Animal Husbandry↗

PubMed2005

Foodborne infections in France.

To quantify the impact of foodborne diseases on health, and set priorities for data collection, prevention and control of these diseases, we compiled and analyzed information from surveillance systems and other sources on the morbidity and mortality due to foodborne infectious diseases in mainland France in the last decade of the 20th century. Illness due to 13 bacteria, two viruses, and eight parasites were studied. The number of foodborne infections, hospitalizations, and deaths were estimated from multiple data sources. For each agent, several estimates were derived from the different sources. Estimates were ranked according to their plausibility, based on an assessment of the validity of the data source, and are presented as a "plausible interval" consisting of a low and high estimate. We estimate that these pathogens caused 10,200-17,800 hospitalizations per year. Salmonella is the most frequent cause (5,700-10,200 cases), followed by Campylobacter (2,600-3,500 cases) and Listeria (304 cases). Toxoplasmosis accounts for the majority of hospitalizations (426 cases) attributable to the studied parasitic infections. The number of deaths related to foodborne infection was estimated between 228 and 691. Bacterial pathogens account for the majority (191 to 652) of deaths of which 92 to 535 are attributable to salmonellosis, ranking as the first cause of death, and 78 to listeriosis, the second cause. Salmonella, Campylobacter, and Listeria are the main causes of severe foodborne illness in France. For several pathogens, data are insufficient to derive exact estimates of the disease burden. Nevertheless, it has been possible to derive plausible estimates for the majority, and to rank them according to their impact on public health.

Campylobacter Infections↗

PubMed2005

Hybridization dynamics between sympatric species of trout: loss of reproductive isolation.

Although reinforcement should enhance reproductive barriers in sympatric species, sympatric trout species do hybridize. Using mitochondrial and nuclear species markers, we investigated hybridization directionality, hybrid mating biases, and selection against hybrids in 13 sympatric cut-throat and rainbow trout populations on Vancouver Island, Canada. Approximately 50% of the genotyped fish were hybrid (F1 or higher-order) and populations ranged from very recent (all F1 hybrids) to extremely advanced higher-order hybridization. Overall, interbreeding was reciprocal, although some populations showed directional hybridization. Pronounced cytonuclear disequilibrium in post-F1 hybrids indicated a remarkable mating bias not previously reported, which is most likely because of behavioural reproductive preferences. Selection against hybrids was observed in only two populations, indicative of extrinsic selection. Two populations were 'hybrid swarms', with a complete loss of reproductive isolation. The complex hybridization dynamics in this system represent a valuable natural experiment of the genetic and evolutionary implications of recent and on-going interspecific hybridization.

Animals↗

PubMed2005

Development of performance indicators for the bovine clinical salmonellosis surveillance network in France.

Performance indicators are variables used to calculate on a continuous basis the operational level of a surveillance network's priority activities. A 10-step process was developed to enable network coordinators to identify specific performance indicators to help them monitor their networks. The methodology was based on a listing of surveillance activities, the definition and choice of network's global priority objectives, the construction of performance indicators and monitoring tables and the implementation of the system within the network. This process was implemented for the bovine clinical digestive salmonellosis surveillance network in France (RESSAB). The process produced a list of 26 activities synthesized into 15 global objectives, from which 12 were retained as priority objectives. This made it possible to develop 12 performance indicators. Indicators retrospectively calculated for the year 2003 indicated that RESSAB was operating according to the objectives set by the network's stakeholders and its financial supporter. The methodology was implemented successfully and was not very time consuming (12 person-days) or expensive. The decision makers and actors in the network quickly appropriated the system. The methodology can thus be considered validated through this example. Nevertheless, the risks inherent in the use of performance indicators must be addressed by ensuring the relevance of the selected indicators through external assessment and by prioritizing an internal and participatory approach to avoid a misuse of the performance indicators. In addition, considering that performance indicators address only the operation of the network, relevance of surveillance procedure should be addressed by external evaluation.

Animals↗

PubMed2003

Expression of androgen receptor coactivators in normal and cancer prostate tissues and cultured cell lines.

BACKGROUND: In prostate cancer cell lines, androgen receptor (AR) coactivators modulate the transcriptional activity of AR. However, very little is known about their expression in normal prostate tissue and during progression to cancer. METHODS: AR and coactivators ARA54, ARA55, ARA70, and SRC1 RNA were analyzed by RT-PCR in normal and tumoral tissues of the same prostate, in prostate cell lines, and after hormonal treatments of prostate epithelial cells. RESULTS: AR-coactivators were expressed in normal and tumoral tissues and in cultured prostate cells; only ARA55 expression was decreased in tumoral relative to normal tissue of all seven prostates analyzed. It was not expressed in LNCaP and DU145 cancer cells and low in PNT2 immortalized cells in which all coactivator's expression were down regulated by DHT and up regulated by E2. In addition, coactivator's expression was increased in hyperplastic relative to normal prostate fibroblasts. CONCLUSIONS: ARA55 is both an AR coactivator and a focal adhesion protein (Hic-5). Its role in the progression of prostate carcinoma may therefore involve these two different functions. Its decrease in cancer tissue suggests that it plays a different role than that expected, namely, facilitate cell proliferation and therefore mobility and metastasis.

Carcinoma↗

PubMed2003

Quantitative risk assessment of human salmonellosis from the consumption of a turkey product in collective catering establishments.

The quantitative risk assessment (QRA) approach recommended by the Codex Alimentarius Commission was used to assess the risk of human salmonellosis from the consumption of 'cordon bleu', a specific turkey product, in collective catering establishments (CCEs) of a French department. The complete process was modeled and simulated, from the initial storage in the CCE freezer to the consumption, using a Monte Carlo simulation software. Data concerning the prevalence of contaminated 'cordon bleu', the level of contamination of Salmonella, the cooking and storage process were collected from 21 CCEs and 8 retailers of 'cordon bleu' in the selected department. Thermal inactivation kinetics for Salmonella were established to estimate the effect of heat treatment on the concentration in the product and to calculate the dose that could be ingested by the consumer. The Beta-Poisson dose-response model of Rose and Gerba [Water Science and Technology 24 (1991) 29] with the specific parameters for Salmonella was used to estimate the probability of infection related to the ingestion of a particular dose and a factor was applied to estimate the probability of illness from ingestion. The individual risk of salmonellosis, the risk of outbreak and the number of cases were calculated using Monte Carlo simulation method. The risk of salmonellosis was close to zero when the 'cordons bleus' were cooked in the oven. Therefore, the risk was calculated for the fryer cooking since the insufficient cooking time observed was, sometimes, at the origin of low temperatures (37-89 degrees C). The influence of both the initial concentration of Salmonella in the product and the heat storage before consumption on the final risk was studied. For a high initial concentration of Salmonella in the product, when the 'cordons bleus' are fryer cooked, the average risk of salmonellosis was equal to 3.95 x 10(-3) without storage before consumption and 2.8 x 10(-4) if the product is consumed after storage. This paper presents the results of the QRA and discusses risk management options to minimize the risk of salmonellosis.

Animals↗

PubMed2002

Ring vaccination against foot-and-mouth disease.

The study of the available information, notably after the epizootic of foot-and-mouth disease (FMD) which raged in Western Europe in 2001, shows that, in the current conditions of the international sanitary rules relative to this disease, in a FMD-free country of Western Europe accidentally infected, ring vaccination is a solution which, with regard to preventive slaughter, contains more inconveniences (notably economic) than advantages. The appeal to ring vaccination would be interesting only as far as the international sanitary rules would be modified by taking into account the results expected from the coordinated use of highly purified vaccines and differential research kits (vaccine-linked versus infection-linked antibodies). Propositions are this way made.

Animals↗

PubMed2001

Implication of milk and milk products in food-borne diseases in France and in different industrialised countries.

A study was carried out to estimate the proportion of diseases due to milk and milk products among food-borne diseases recorded in France and in other countries since 1980. Particular attention was given to whether the milk involved was heat-treated or not. Four etiologic agents were considered: Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, and pathogenic Escherichia coli. An overview of food-borne disease annual reports from seven countries indicated that milk and milk products were implicated in 1-5% of the total bacterial outbreaks; however, details about the type of product and milk involved were usually not provided. When considering 60 outbreaks and four single cases described in the literature and implicating milk and milk products, confirmed or suspected food vehicles were distributed as follows: milk, 39.1%, cheese, 53.1%, other milk products, 7.8%. Overall, 32.8% of the food vehicles were made from pasteurised milk; 37.5% from raw milk; 10.9% from milk stated as "unpasteurised"; and 18.8% from unspecified milk. Salmonella spp. were responsible for 29 outbreaks, L. monocytogenes for 10 outbreaks and four well-documented single cases, pathogenic E. coli for 11 outbreaks, and S. aureus for 10 outbreaks. Analysis of unpublished data about food-borne disease outbreaks, listeriosis excluded, collected by the coordinator of the French surveillance system from 1992 to 1997, revealed 69 documented outbreaks for which milk and milk products were confirmed as the vehicle by the isolation of the etiologic agent. The food vehicles were distributed as follows: milk, 10%; cheese, 87%; others, 3%. UHT milk accounted for 1.5%, raw milk and raw milk products for 48%, and milk and milk products from unspecified milk for 50.5% of the 69 outbreaks. S. aureus was by far the most frequent pathogen associated with these outbreaks (85.5% of the outbreaks), followed by Salmonella (10.1%). This study demonstrates the limitations of the surveillance systems and the difficulties in estimating the contribution of milk and milk products to food-borne diseases. In particular, it was not possible to find out in many outbreaks what heat treatment, if any, the milk had undergone.

Animals↗

PubMed2001

A qualitative assessment of the risk of introducing foot and mouth disease into Russia and Europe from Georgia, Armenia and Azerbaijan.

A qualitative risk assessment was performed to evaluate the risk of introducing foot and mouth disease (FMD) virus into Russia and the rest of Europe from the countries of Transcaucasia (Armenia, Azerbaijan and Georgia). The assessment was based on data collected during a three-week mission to these countries by the Food and Agriculture Organization, the European Union and the Office International des Epizooties in March 1999. Due to the strong involvement of the local veterinary services, much information was obtained. Although the data were not sufficient to allow a quantitative risk assessment to be performed, the investigation served as a useful initial approach, prior to undertaking a quantitative risk assessment. The risk of FMD virus infection is a function of two elements, namely: the probability of the hazard (virus infection) occurring, and the magnitude of the consequences. The probability of the hazard occurring is the product of the probability of entry of the virus and the probability of exposure to the virus. These elements were assessed using the following parameters: prevalence of infection; volume of trade; capacity of the virus to survive; and potential for infection. The magnitude of the consequences is derived from the probability of transmission and spread. Combining these parameters, the probability of occurrence of the hazard was rated as 'moderate'. Economic consequences of potential transmission and spread of FMD, in the local context, were rated as 'negligible'. As a result, the overall risk of introducing FMD virus into Russia and the rest of Europe from Trancaucasia was rated as 'low' at the time of evaluation. The method and results are presented to serve as a basis for further discussion.

Animals↗

PubMed2000

A survey of PCDD and PCDF in French long-life half-skimmed drinking milk.

A national survey was carried out in order to assess the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in long-life half-skimmed drinking milk produced and consumed in France. 151 Samples were collected from 33 dairy establishments selected for their production amounts following a random sampling scheme. 148 of the 151 results were finally used for statistical assessment. The mean concentration of 2,3,7,8-TCDD toxicity equivalent found is 0.65 pg/g of milk fat. This result is far below the threshold recommended by the European Union.

Animals↗

PubMed2000

[Radiotherapy of localized prostatic cancer: follow-up of 48 patients. G.C.C.P. (Cooperative Group for the Study of Prostatic Cancer)].

OBJECTIVE: To evaluate the safety and long-term efficacy of curative-intent radiation therapy in patients with apparently localized prostate cancer. METHOD: 48 patients with T < 3 M0 prostate cancer recruited between 1981 and 1985 received regular clinical follow-up for at least ten years or until their death. Radiation therapy was given according to the protocols established by Ray and Bagshaw. RESULTS: Radiation therapy was safe and effective in most patients. The rate of escape phenomenon was less than 10% after two years. Tumor control rates were greater than 80% after five years and 50% after ten years. Unfortunately, local remission, even when prolonged, did not necessarily indicate a complete cure: 20% of local recurrences developed five to 11 years after radiation therapy. CONCLUSION: Radiation therapy may be the best first-line treatment in men older than 75 years of age and in those whose life expectancy seems shorter than ten years, but should probably not be considered curative.

Aged↗

PubMed2000

[Conservative surgical techniques in the treatment of kidney tumors].

Several conservative operations are available for renal tumours. This article describes the anatomical bases, the measures designed to protect the parenchyma from ischaemia and the various resection techniques. Wedge resection is described in detail, as it appears to be the most rigorous technique.

Humans↗

PubMed2000

Detection of circulating prostate derived cells in patients with prostate adenocarcinoma is an independent risk factor for tumor recurrence.

PURPOSE: To determine whether the presence of prostate-derived cells in the peripheral blood circulation is a marker of prostate cancer and to define the clinical impact of the test. MATERIALS AND METHODS: We tested the peripheral blood of 99 patients with prostate adenocarcinoma (PAC), 79 of them undergoing radical prostatectomy, and 92 controls (31 healthy volunteers, 50 patients with adenoma and 11 with prostatitis) using a highly controlled procedure including reverse-transcriptase polymerase chain reaction (RT-PCR) targeted to prostate-specific antigen (PSA) mRNA. Patients were followed for 26 +/- 12 (range: 4 to 49) months. Forty tumor tissues were analyzed by immunohistochemistry for expression of p53 and E-cadherin antigens. RESULTS: Thirty three (33%) patients with PAC and 2 (2%) controls scored positive (p <0.0001) for the test. Detection of circulating prostatic cells was associated with development of metastases (p <0. 001), with relapse (p <0.001) and with a serum PSA level at diagnosis higher than 15 ng./ml. (p = 0.009). The rate of development of metastases according to time was significantly higher in patients who scored positive for the test (p <0.04). In a multivariate analysis, only the RT-PCR test was an independent risk factor associated with relapse (RR: 6.7). Finally, E-cadherin expression was significantly lower in the tumor tissues of positive patients as compared with those who scored negative for the test (p <0.01). CONCLUSIONS: This RT-PCR procedure, performed at diagnosis and with appropriate controls, is a clinically useful assay in evaluating the risk of tumor recurrence after radical prostatectomy in patients with PAC.

Adenocarcinoma↗

PubMed1999

Mortality and morbidity after nephrectomy for renal cell carcinoma using a transperitoneal anterior subcostal incision.

OBJECTIVES: We have reviewed our surgical experience to document intra- and postoperative mortality and morbidity in 656 patients with renal cell carcinoma who underwent nephrectomy through a transperitoneal anterior subcostal incision (TASI). MATERIALS AND METHODS: From 1986 to 1997 we performed 656 nephrectomies for renal cell carcinoma using a TASI. Details of the surgical procedure are presented together with a retrospective analysis of the postoperative data concerning both the patient and the complications related to this approach. RESULTS: The mean time of operation was 130 min and the mean discharge from hospital 11 days. An additional surgical procedure in relation with the cancer facilitated by this approach was necessary in 2.1% of cases. The rates of intra- and postoperative complications were respectively 6.4 and 29.7%. The rate of intestinal complications was 1.8% and a splenic injury occurred in 8% of left nephrectomy. The mortality rate was 0.6%. CONCLUSIONS: The TASI is a large convenient incision which allows safe control of the renal pedicle in a very large number of renal tumors, even those located in the upper pole of the kidney. The rate of gut complications is very acceptable. Splenic injury is the major problem during left nephrectomy but careful dissection and surgical experience could decrease this complication, especially in case of upper pole renal tumor. We consider the TASI to be the main radical nephrectomy incision for renal cell carcinoma.

Adolescent↗

PubMed1999

[Role of economic studies in animal health decisions: Example of the cost-benefit ratio of eradication of bovine viral diarrhea in France].

To help livestock production groups to rationalise health decisions, and at the request of the Association for the certification of livestock health (Association pour la certification de la santé animale en élevage: ACERSA), an economic study was conducted to assess the possible cost-effectiveness of the eradication of bovine virus diarrhoea in France. The study was performed using a fictitious average region comprising 235,000 cattle belonging to 3,300 farms, which corresponds to one-eighty-fifth of the total cattle population of France. In the first phase of the study, the cost of the disease in this region was estimated to be approximately six million French francs (US$989,937) per year. Subsequently, the cost of an eradication strategy based on the inspection of all animals when introduced into a herd, the screening of permanently-infected immunotolerant animals (IPI) and the elimination of these animals, was evaluated at nearly eleven million francs (US$1,814,884) during the first year. Theories were then formulated regarding the time required to achieve eradication (twenty years) and to reduce the epidemiological parameters (development curve of the eradication of IPI animals and of animals which had given positive results to serological tests). The reduction in the cost of the disease as a result of the eradication policy was then simulated in accordance with the evolution of the epidemiological parameters. Finally, the cost of controlling the disease, together with the residual cost of the disease, were compared with the cost of the disease without control measures. This demonstrated that such an eradication policy would, in theory, only begin to become cost-effective after approximately fifteen years. In view of the long period required to achieve cost-effectiveness, the considerable complexity of implementing an eradication programme and imponderables (particularly concerning virus spread), the recommendation of such a course of action to cattle-breeder groups is questionable. This research demonstrates that a relatively simple economic approach can serve as a useful decision-making aid.

Animals↗

PubMed1999

[Fournier's gangrene involving all of the scrotum: treatment by multiple repeated surgical excisions, diversion colostomy, triple antibiotic therapy and postoperative intensive care].

OBJECTIVES: To describe and analyse the proposed therapeutic modalities to treat a series of patients suffering from Fournier's gangrene involving the entire scrotum. MATERIAL AND METHODS: Four patients with macroscopically identical lesions of Fournier's gangrene involving the entire scrotum were managed by wide surgical debridement, diversion colostomy, triple combination antibiotic therapy, transfer to surgical intensive care, multiple repeated operations under general anaesthesia for excision of atonic tissues and mesh skin grafts. The colostomy was closed after 4 months. RESULTS: All patients survived after skin cover. Three of them were reviewed 2 months after restoration of gastrointestinal continuity and presented a good general status with a satisfactory esthetic result. The fourth patient was lost to follow-up. The mean reoperation rate was 6.5 per patient. The mean intensive care stay was 9.5 weeks. CONCLUSION: The choice of intensive treatment depends on the extent of the lesions. When the entire scrotum is involved, repeated surgical excisions and systematic colostomy, combined with the other treatment modalities appear to be necessary to manage this disease, which still has a serious prognosis.

Adult↗

PubMed1999

[Renal cell carcinoma in a 14-year-old girl with Von Hippel Lindau disease].

We report a new case of renal cancer in the context of Von Hippel Lindau (VHL) disease in a 14-year-old girl. To our knowledge, this is the youngest case reported in the literature. VHL disease is now well known and its prognosis is related to renal cancer, which occurs very early in the patient's life, requiring adequate surveillance of patients carrying the VHL gene to ensure early diagnosis of the cancer, screening of family members and treatment, preferably conservative when permitted by the size and number of tumours, in these patients who are predisposed to developing other renal tumours, in order to delay bilateral nephrectomy and the need for dialysis or even transplantation, to a maximum.

Adolescent↗