Neoadjuvant treatment of pancreatic adenocarcinoma: Chemoradiation or stereotactic body radiation therapy?

Despite recent advances, the prognosis of pancreatic adenocarcinomas remains poor, even for patients with resectable tumors. For these latter, new approaches based on neoadjuvant treatment have been developed. Two components are used: chemotherapy and radiation therapy (RT). Indeed, pre-operative RT has many advantages in terms of efficacy and tolerance. It increases notably the chances of subsequent complete tumor resection. Several prospective trials are currently ongoing to clarify its place in the therapeutic arsenal. Another crucial question is to know which is the best RT technique: conventional normofractionated chemoradiotherapy or hypofrationated stereotactic body RT?

Unravelling direct and indirect contact patterns between duck farms in France and their association with the 2016-2017 epidemic of Highly Pathogenic Avian Influenza (H5N8).

Live animal movements generate direct contacts (via the exchange of live animals) and indirect contacts (via the transit of transport vehicles) between farms, which can contribute to the spread of pathogens. However, most analyses focus solely on direct contacts and can therefore underestimate the contribution of live animal movements in the spread of infectious diseases. Here, we used French live duck movement data (2016-2018) from one of the largest transport companies to compare direct and indirect contact patterns between duck farms and evaluate how these patterns were associated with the French 2016-2017 epidemic of highly pathogenic avian influenza H5N8. A total number of 614 farms were included in the study, and two directed networks were generated: the animal introduction network (exchange of live ducks) and the transit network (transit of transport vehicles). Following descriptive analyses, these two networks were scrutinized in relation to farm infection status during the epidemic. Results showed that farms were substantially more connected in the transit network than in the animal introduction network and that the transit of transport vehicles generated more opportunities for transmission than the exchange of live animals. We also showed that animal introduction and transit networks' statistics decreased substantially during the epidemic (January-March 2017) compared to non-epidemic periods (January-March 2016 and January-March 2018). We estimated a probability of 33.3 % that a farm exposed to the infection through either of the two live duck movement networks (i.e. that was in direct or indirect contact with a farm that was reported as infected in the following seven days) becomes infected within seven days after the contact. However, we also demonstrated that the level of exposure of farms by these two contact patterns was low, leading only to a handful of transmission events through these routes. As a consequence, we showed that live animal movement patterns are efficient transmission routes for HPAI but have been efficiently reduced to limit the spread during the French 2020-2021 epidemic. These results underpin the relevance of studying indirect contacts resulting from the movement of animals to understand their transmission potential and the importance of accounting for both routes when designing disease control strategies.

Combination of radiation therapy-immunotherapy for head and neck cancers: Promises kept?

Chemoradiotherapy with concurrent cisplatin has been the standard treatment for locally advanced head and neck squamous cell carcinoma (HNSCC) for over 20 years. Recently, immunotherapy, a new therapeutic class, has emerged for patients with recurrent or metastatic HNSCC and has significantly extended their survival. Will it bring the same benefit to patients with localized tumors? There is a strong rationale for combining radiation therapy and checkpoint inhibitors for HNSCC. Indeed, radiation therapy can have both immunostimulatory and immunomodulatory effects. This is what explains the famous abscopal effect. The aim of this review is to present the data available on the combination of radiation therapy and immunotherapy for HNSCC.

[Which indications for inpatient admission of a patient with an addiction? Application of the chronic disorders model. A face validity study]. / Quelles indications d'hospitalisation d'un patient avec addiction ? Application du modèle des pathologies chroniques. Une étude de validité apparente.

INTRODUCTION: The medical identification of an addiction (use disorder) often results in inpatient admission with a view to its definitive suspension. However, for other chronic diseases, inpatient admission is indicated for specific situations and the objective is not the definitive suspension of the chronic disease. Our goal was to clarify addiction as a chronic disease and to determine explicit indications for inpatient admission. METHOD: Three-stage face validity study: (1) from the analysis of consensual definitions, search by the subset theory whether addiction can be considered as a chronic disease; (2) Develop generic indications for inpatient admissions based on the analysis of chronic disease care pathways validated by the HAS (French Health Agency) and apply them to addiction; (3) Validate by Delphi expert consensus method the determined indications. RESULTS: Step (1) showed that the definition of addiction allowed to include it in that of chronic disease. Step (2) determined 7 indications for inpatient admission of a patient with a chronic disease, and its application to addiction identified 15 indications for inpatient admission of a patient with addiction. In step (3), the Delphi method yielded consensus on 14 of the 15 indications. CONCLUSION: By clarifying addiction as a chronic disease, we were able to determine 14 indications for inpatient admission of a person with an addiction and to distinguish them from the long-term care of addiction. These explicit indications can help the general practitioner or community psychiatrist to better manage patients with addiction on the basis of their expertise with chronic diseases management.

[Gastric and pancreatic cancers: Will neoadjuvant (chemo)radiotherapy replace adjuvant chemoradiotherapy?] / Cancers gastriques et pancréatiques : la (chimio)radiothérapie néoadjuvante remplacera-t-elle la chimioradiothérapie adjuvante ?

For many years, adjuvant chemoradiotherapy remained essential in the therapeutic management of gastric and pancreatic adenocarcinomas. For these tumours, surgical excision, the only hope of offering the patient prolonged survival, is only possible in 20% of cases. The median survival of operated patients is only 12 to 20 months due to the frequency of locoregional and/or metastatic recurrences. For stomach cancers, adjuvant chemoradiotherapy is justified by the results of the phase III trial Intergroup 0116 published by MacDonald et al. The gain in survival was at the cost of significant toxicity. This treatment was supplanted in the early 2000s by perioperative chemotherapy. Currently, neoadjuvant chemoradiotherapy clinical studies are ongoing with the aim of improving treatments observance and tolerance. For pancreatic cancers, the role of adjuvant chemoradiotherapy has long been discussed because of trials with contradictory results. Neoadjuvant radiotherapy has many advantages in terms of efficacy and tolerance. It increases the chances of subsequent complete tumour resection. Several prospective trials are currently ongoing to clarify its place in the therapeutic arsenal.

Spatiotemporal prediction of Escherichia coli and Enterococci for the Commonwealth Games triathlon event using Bayesian Networks.

A number of Bayesian Networks were developed in order to nowcast and forecast, up to 4 days ahead and in different locations, the likelihood of water quality within the 2018 Commonwealth Games Triathlon swim course exceeding the critical limits for Enterococci and Escherichia coli. The models are data-driven, but the identification of potential inputs and optimal model structure was performed through the parallel contribution of several stakeholders and experts, consulted through workshops. The models, whose main nodes were discretised with a customised discretisation algorithm, were validated over a test set of data and deployed in real-time during the Commonwealth Games in support to a traditional water quality monitoring program. The proposed modelling framework proved to be cost-effective and less time-consuming than process-based models while still achieving high accuracy; in addition, the added value of a continuous stakeholder engagement guarantees a shared understanding of the model outputs and its future deployment.

Combining radiation therapy and cancer immune therapies: From preclinical findings to clinical applications.

Besides its direct cytotoxic effect on the tumor cells, radiation therapy is also able to elicit an immune-mediated systemic anti-tumor response, resulting in tumor regression in irradiated sites but also within distant out of field secondary lesions and providing a long-term anti-tumor response. It is now clear that associating ionizing radiation with immune therapies can enhance radio-induced anti-tumor immune responses. Over the last decade, such a combination aroused considerable interest among the scientific community, with many preclinical models and clinical trials, using many types of immune therapies and radiation regimens. In this article, we summarize the main mechanisms underlying radio-induced anti-tumor responses. We will then present an extended overview of the recent preclinical and clinical research built on this background of combined radiation and immune therapy, shedding light on what we know so far about such a promising strategy.

Circulation of bluetongue virus 8 in French cattle, before and after the re-emergence in 2015.

Bluetongue virus serotype 8 (BTV-8) re-emerged in Central France in August 2015. The viral strain identified is nearly identical to the one that circulated during the 2006/2009 massive outbreak throughout Europe. To address the question of an undetected BTV-8 circulation on the French territory, a serological study was conducted on young cattle along a transect of seven departments, three of them located in areas where the virus presence had been confirmed by RT-PCR by winter 2015/2016. Sera from 2,565 animals were collected during the winters preceding and following the re-emergence, with 414 animals being sampled in each of the two consecutive years. All samples were tested by competitive ELISA (IDVet) and, when enough serum was available, ELISA-positive samples were confirmed by seroneutralization tests. In areas with infected holdings, seropositive animals were found before the re-emergence (N = 14 of 511), significantly more on the following year (N = 17 of 257), and eight animals (N = 158) seroconverted over 2015. Seropositive animals were also detected as early as winter 2014/2015 in one department without known infected holdings (N = 12 of 150), and in winter 2015/2016 in three of them (N = 21 of 555), where seven animals (N = 154) seroconverted over 2015. These results suggest that BTV-8 may have spread at low levels before the re-emergence, even in areas considered virus-free. Unfortunately, whole blood from the seropositive animals was not available to definitely confirm the virus presence by RT-PCR.

Serological status for BTV-8 in French cattle prior to the 2015 re-emergence.

Undetected in Europe since 2010, bluetongue virus serotype 8 (BTV-8) re-emerged in August 2015 in Central France. To gain insight into the re-emergence on the French territory, we estimated the seroprevalence in cattle before the detection of BTV-8 in 2015, in areas differentially affected by the current outbreak. A retrospective survey based on the analysis of stored sera was thus conducted in the winter preceding the re-emergence in seven French departments including the one where the virus was first detected. A total of 10,066 sera were retrieved from animals sampled in 444 different herds in winter 2014/15. Between-herd seroprevalence revealed the presence of seropositive animals in almost all herds sampled (97.4%). The animal-level seroprevalence averaged at 44%, with a strong age pattern reflecting the cumulative exposure to both natural infection and to vaccination. A multivariable analysis allowed separating the respective effects of both exposures. A higher proportion of seropositivity risk was attributed to vaccination (67.4%) than to exposure to natural infection (24.2%). The evolution of seroprevalence induced by the two main risk factors in 74 mainland departments was reconstructed between the vaccination ban (2013) and the re-emergence (2015). We showed a striking decrease in seroprevalence with time after the vaccination ban, due to population renewal, which could have facilitated virus transmission leading to the current outbreak situation.

Observed volatilization fluxes of S-metolachlor and benoxacor applied on soil with and without crop residues.

Volatilization may represent a major dissipation pathway for pesticides applied to soils or crops, and these losses may be modified by soil surface conditions or in the presence of plant residues. This paper investigates the effect of surface conditions on volatilization through experimental results. The two experiments consisted of volatilization flux measurements for 3 days after an application of S-metolachlor together with benoxacor: one with two wind tunnels to compare the effect of the presence of crop residues on the soil on volatilization losses and another one at the field scale from bare soil without crop residues. Volatilization fluxes were large immediately after application (between 77 and 223 ng m-2 s-1 for S-metolachlor depending on experimental conditions), decreasing down to a few nanograms per square meter per second on the last day. Volatilization fluxes followed a diurnal cycle driven by environmental conditions. The losses found for both compounds were in accordance with their physicochemical properties. The crop residue on the soil surface modified soil surface conditions-primarily the soil water content essentially, the degradation of S-metolachlor, and the dynamics of volatilization loss.

Short Report: Identification of a Potential Marker of Anaplasma Phagocytophilum Associated with Cattle Abortion.

Anaplasma phagocytophilum is a tick-borne pathogen that causes tick-borne fever in domestic ruminants. Tick-borne fever is characterized by diverse symptoms and occasionally causes abortions in domestic ruminants, resulting in significant economic impact. However, in France, the potential frequency of A. phagocytophilum-related abortions is unknown, and thus, it remains difficult to estimate the full extent of its economic impact. This gap in our knowledge is likely explained, at least in part, by the absence of suitable and specific tools capable of detecting A. phagocytophilum associated with abortion. Our objective was to identify a genetic marker able to differentiate A. phagocytophilum strains isolated from domestic ruminants that had aborted compared to those that had not. Thus, we typed a total of 123 A. phagocytophilum obtained from cattle, of which 25 originated from cows that had aborted, via multiple-locus variable-number tandem repeat (VNTR) analysis. These included 56 new A. phagocytophilum samples and 67 previously published A. phagocytophilum samples. A multivariate logistic model demonstrated that the triple-repeat allele of the APV-A VNTR was statistically more frequent in A. phagocytophilum from cattle that had aborted, compared to A. phagocytophilum from cattle that had not aborted (P = 0.03), while controlling for any regional effects (P < 0.0001). For four other VNTR, there were no statistical associations between specific alleles and abortion. The APV-A triple-repeat VNTR allele could thus act as a marker of A. phagocytophilum involved in abortions. If this hypothesis is confirmed in additional samples from other regions, this marker could then be utilized in the development of A. phagocytophilum abortive strain surveillance measures.

Factors associated with Toxoplasma gondii infection in confined farrow-to-finish pig herds in western France: an exploratory study in 60 herds.

BACKGROUND: Infection by Toxoplasma gondii postnatally can occur after ingestion of contaminated meat or water (tissue cysts/oocysts). In Europe, percentage of meat borne infections is estimated between 30 and 63 %, out of which pork makes the most important source. The aim of this study was to (i) investigate the seroprevalence of T. gondii in intensive pig farms from western France; and (ii) identify the risk factors associated with seropositivity. METHODS: Data were collected between November 2006 and February 2008 in 60 intensive farrow-to-finish farms, where sera were taken from 3595 fattening pigs, weaned and suckling piglets. Information about three classes of potential seropositivity risk factors were obtained through a questionnaire concerning: (i) breeding characteristics; (ii) farm management; and (iii) husbandry and hygiene. The modified agglutination test (MAT) was used for detection of specific anti T. gondii antibodies in pig sera, starting from 1/6 dilution. RESULTS: The overall proportion of seropositive animals was 6.9 %, but the proportion of herds with at least one positive pig was 100 %. Multivariate logistic mixed model showed an increased seropositivity risk in weaned compared to suckling piglets, and a decreasing risk for mid-sized and large farms. The presence of a Danish entry facility, that clearly separates clean and dirty areas, had a protective effect on T. gondii seropositivity as well. CONCLUSIONS: The observed proportion of herds with at least one T. gondii seropositive animal provides further evidence that even in confined conditions of pig breeding, infection occurs, and is common. The highest risk for acquiring T. gondii is at the end of weaning period. Smaller confined pig farms demonstrate higher T. gondii seropositivity levels. This study also showed that Danish entry on farm buildings provides effective protection against T. gondii.

Interlaboratory ring trial to evaluate CFT proficiency of European laboratories for diagnosis of glanders in equids.

To evaluate the routine complement fixation test (CFT) used to detect Burkholderia mallei antibodies in equine sera, an interlaboratory proficiency test was held with 24 European laboratories, including 22 National Reference Laboratories for glanders. The panels sent to participants were composed of sera with or without B mallei antibodies. This study confirmed the reliability of CFT and highlighted its intralaboratory reproducibility. However, the sensitivity of glanders serodiagnosis and laboratory proficiency may be improved by standardising critical reagents, including antigens, and by developing a standard B mallei serum.

Toxoplasma gondii infection in pork produced in France.

The aim of this study was to assess the seroprevalence of the Toxoplasma gondii parasite in pork produced in France, and to determine infection risk factors. An innovative survey was designed based on annual numbers of slaughtered pigs from intensive and outdoor farms in France. A total of 1549 samples of cardiac fluids were collected from pig hearts to determine seroprevalence using a Modified Agglutination Test. Of those, 160 hearts were bio-assayed in mice to isolate live parasites. The overall seroprevalence among fattening pigs was 2·9%. The adjusted seroprevalence in pigs from intensive farms was 3·0%; the highest in sows (13·4%); 2·9% in fattening pigs and 2·6% in piglets. Adjusted seroprevalence in fattening animals from outdoor farms was 6·3%. Strains were isolated from 41 animals and all were genotyped by Restriction Fragment Length Polymorphism as type II. Risk-factor analysis showed that the risk of infection was more than three times higher for outdoor pigs, and that sows' risk was almost five times higher than that of fattening animals. This study provides further evidence of extensive pork infection with T. gondii regardless of breeding systems, indicating that farm conditions are still insufficient to guarantee 'Toxoplasma-free pork'.

Seroprevalence of West Nile and Usutu viruses in military working horses and dogs, Morocco, 2012: dog as an alternative WNV sentinel species?

A serosurvey of 349 military working horses and 231 military working dogs was conducted in ten sites in Morocco in 2012. This survey revealed a high level of exposure of these animals to flaviviruses: seroprevalence rates of 60% in horses and of 62% in dogs were observed using a competitive West Nile virus (WNV) enzyme-linked immunosorbent assay (cELISA). Seroneutralization test results showed that the majority of cELISA-positive results were due to exposure to WNV. Further assays conducted in vaccinated horses with a DIVA (Differentiating Infected from Vaccinated Animals) test indicated that anti-WNV antibodies had been stimulated through WNV natural infection. Moreover, in both species, seroneutralization tests suggested an exposure to Usutu virus (USUV). Data analysis did not show any significant difference of cELISA seropositivity risk between horses and dogs. Dogs may thus represent an interesting alternative to equines for the serological surveillance of WNV or USUV circulation, especially in areas where equine vaccination precludes passive surveillance (based on the detection of West Nile fever cases) in horses.

Characterization of five associations of F8 missense mutations containing FVIII B domain mutations.

INTRODUCTION: Haemophilia A (HA) is a bleeding disorder due to an absence or a reduced activity of coagulation factor VIII (FVIII) caused by mutations in F8 gene. Missense mutations represent approximately 45% of the reported molecular defects in HA. However, only few missense mutations in FVIII B domain have been described. AIM: The aim of this study was to characterize five genetic variations (three novels and two previously reported) localized in the FVIII B domain. In all cases, an additional missense variation located outside the FVIII B domain was found. We investigated each of these variations separately and in combination too for their contribution to HA phenotype. METHODS: F8 variants were transiently expressed in COS-1 cells. Media and cell lysates were collected after 72 h. Then, FVIII activity, secretion and thermostability were analysed and compared to FVIII wild-type. RESULTS: The 5 FVIII B domain variants showed normal FVIII: C (98.5-128.5%) and FVIII: Ag (97.7-154%). No synergistic effect was observed between the B domain variant and their associated mutations. In contrast, the variants located outside the B domain, p.V682L, p.S714L, p.V592D and p.C573F revealed significantly decrease of FVIII: C with values in the range 3.5-44.5% (p < 0.05). However, the p.G224R variant showed FVIII: C and FVIII: Ag values no significantly different from FVIII-WT. CONCLUSION: The FVIII B domain variants, p.D963N, p.S806T, p.G873D, p.H998Q and p.Q1225R may be considered as polymorphism or non-pathologic mutations. In five patients, clinical phenotype could be explained by the additional causative missense mutation. For the p.G224T variant further splicing studies are necessary to determine its pathogenicity.

Spatial-temporal Variations of Bovine Tuberculosis Incidence in France between 1965 and 2000.

We analysed the spatiotemporal variations of bovine tuberculosis (bTB) incidence between 1965 and 2000 in France at the department level (95 areas). Using a Bayesian space-time model, we studied the association between the evolution of bTB incidence and changes of cattle population structure and of herd management practices. Several spatiotemporal hierarchical Bayesian models were compared, and the deviance information criterion was used to select the best of them. Southern France remained a high-risk area over the analysed period, whereas central and western regions were low-risk areas. Besides the frequency of tuberculin skin testing (fixed according to bTB incidence in the preceding years), four factors were associated with an increased risk of bTB: the average herd density and size, the percentage of dairy cows in the cattle population, and the percentage of permanent grassland in cultivated surfaces area. These four factors are linked to the progressive professionalization and specialization of cattle farming, with the disappearance of family farms and of the intensification of breeding systems (especially in dairy farms after the application of the milk quota system in the 1980s). Both trends probably played a significant role in reducing the risk of bTB in France between 1965 and 2000, besides mandatory detection and control procedures.

West Nile virus epizootics in the Camargue (France) in 2015 and reinforcement of surveillance and control networks.

West Nile virus (WNV) infection is a non-contagious disease mainly transmitted by the bites of infected mosquitoes from the genus Culex. The virus is maintained in a mosquito-bird-mosquito cycle, and can accidentally be transmitted to mammalian hosts. Among mammalian hosts, equines and humans are the most sensitive to WNV infection and can develop severe meningoencephalitis. As WNV infections are zoonotic and can be severe in humans and equines, West Nile fever is considered to be a public and animal health concern. After a silent period of almost ten years, WNV re-emerged in France at the periphery of the Camargue area during the summer of 2015, underlining the fact that the Camargue area creates favourable conditions for WNV emergence and amplification in France. The French Network for Epidemiological Surveillance of Equine Diseases (Réseau d'Épidémio-Surveillance en Pathologie Équine [RESPE]) facilitated the early detection of WNV cases in horses. In total, 49 horses were found to be infected; among them, 44 presented clinical signs, 41 with meningoencephalitis and three with hyperthermia only. Six horses among the 41 with nervous symptoms died from the disease or were euthanised (a case fatality rate of 14.6%). The authors describe the characteristics of the 2015 WNV epizootics, the early detection of the first WNV equine cases via the RESPE network and the coordination of WNV surveillance in France.

L'infection par le virus de West Nile est une maladie non contagieuse essentiellement transmise lors de piqûres de moustiques infectés appartenant au genre Culex ; le virus se maintient dans la nature au moyen d'un cycle moustique­ oiseau­moustique ; la transmission à des hôtes mammifères a lieu de manière accidentelle. Parmi les mammifères hôtes, les plus sensibles à l'infection par le virus de West Nile sont les équidés et l'homme, chez qui l'infection peut se manifester sous forme d'une méningo-encéphalite sévère. Les infections par le virus de West Nile étant des zoonoses potentiellement graves chez l'homme et chez les équidés, la fièvre de West Nile doit être considérée comme une priorité de santé publique et animale. Resté silencieux pendant plus d'une décennie, le virus de West Nile est réapparu en France à l'été 2015 en bordure de la Camargue, confirmant que les conditions de cette région sont favorables à l'émergence et à l'amplification du virus. Le réseau français d'épidémiosurveillance en pathologie équine (RESPE) a contribué à la détection précoce du virus de West Nile chez les chevaux. Au total, 49 chevaux étaient infectés, parmi lesquels 44 présentaient des signes cliniques, correspondant à une méningo-encéphalite pour 41 d'entre eux et à une hyperthermie seule pour les trois autres. Six chevaux parmi les 41 qui présentaient des signes neurologiques ont succombé à la maladie ou ont été euthanasiés (taux de létalité de 14,6 %). Les auteurs de cet article décrivent les principales caractéristiques de l'épizootie de 2015 due au virus de West Nile ainsi que la détection précoce des premiers cas équins grâce au réseau RESPE et la coordination des activités de surveillance du virus en France.

La infección por el virus West Nile es una enfermedad no contagiosa que se transmite básicamente por la picadura de mosquitos infectados del género Culex. El virus, que se instala en un ciclo mosquito­ave­mosquito, también puede transmitirse accidentalmente a mamíferos, de entre los cuales los más sensibles a la infección son los equinos y el ser humano, que pueden contraer graves meningoencefalitis. Puesto que las infecciones por este virus son zoonóticas y pueden revestir gravedad en personas y equinos, se considera que la fiebre West Nile es una enfermedad de importancia sanitaria y zoosanitaria. En Francia, tras un periodo silente de más de diez años, el virus reapareció en verano de 2015 en la periferia de la zona de la Camarga, poniendo así de manifiesto que esta zona genera condiciones propicias al surgimiento y la amplificación del virus en el país. La red francesa de vigilancia epidemiológica de patologías equinas (Réseau d'Épidémio-Surveillance en Pathologie Équine: RESPE]) facilitó la rápida detección de caballos infectados por el virus West Nile. Se detectaron en total 49 animales infectados, entre ellos 44 con signos clínicos, de los que 41 sufrían meningoencefalitis y tres solo presentaban hipertermia. Seis de los 41 caballos que mostraban signos neurológicos murieron a causa de la enfermedad o fueron sacrificados con métodos de eutanasia (lo que supone una tasa de letalidad del 14,6%). Los autores describen las principales características de la epizootia causada por el virus West Nile en 2015, la pronta detección de los primeros casos de caballos infectados gracias a la red RESPE y la coordinación de las labores de vigilancia del virus en Francia.

Assessment of Chlamydia psittaci Shedding and Environmental Contamination as Potential Sources of Worker Exposure throughout the Mule Duck Breeding Process.

Chlamydia psittaci is an obligate intracellular bacterium responsible for avian chlamydiosis, otherwise known as psittacosis, a zoonotic disease that may lead to severe atypical pneumonia. This study was conducted on seven mule duck flocks harboring asymptomatic birds to explore the circulation and persistence of C. psittaci during the entire breeding process and assess the potential sources of worker exposure. Cloacal swabs and air samples were taken on each occasion requiring humans to handle the birds. In parallel, environmental samples, including dust, water, and soil, were collected. Specific real-time PCR analyses revealed the presence of C. psittaci in all flocks but with three different shedding patterns involving ducks about the age of 4, 8, and 12 weeks with heavy, moderate, and low excretion levels, respectively. Air samples were only positive in flocks harboring heavy shedders. Dust in flocks with heavy or moderate shedders carried chlamydial loads strongly associated with the loads detected in avian and soil samples. Environmental contamination, significantly correlated with shedding dynamics, was considered to be the most probable source of exposure. The high prevalence of bacteriophage Chp1 in all flocks, mostly jointly present with chlamydia, suggests an important factor in C. psittaci persistence, thus creating a greater risk for humans. A survey conducted in these flocks regarding farming practices and activities showed that disinfection seems to be the most promising practice for reducing C. psittaci prevalence in ducks and that the place and the duration of action during operations seem to be potential risk factors. Strict adherence to good practices is strongly recommended.

Usefulness of an in vitro cellular expression model for haemophilia A carrier diagnosis: illustration with five novel mutations in the F8 gene in women with isolated factor VIII:C deficiency.

This study aims to determine the way to predict the haemophilia A (HA) carrier status and the potential severity in six females with low FVIII: C levels (<0.50 IU mL(-1) ), F8 gene variations and without family history of HA. Except p.Ser577Tyr, F8 gene variations that we reported have never been described (p.Leu107His, p.Pro521Leu, p.Val682Leu, p.Leu2032Pro, p.Ala315dup). Prediction of their potential causal impact was studied by two strategies: bioinformatics approaches and site-directed mutagenesis followed by FVIII cellular expression into COS-1 cell. FVIII clotting assay ( FVIII: C) and antigen ( FVIII: Ag) were assayed in vitro. In silico analysis showed the probably damaging effect of all substitutions and the full conservation of the residues across mammalian species, except for p.Leu2032Pro. The in vitro variant expression model showed abnormal intra and/or extracellular FVIII: C and FVIII: Ag levels for five mutations, which suggest their causality in HA and provide informations about the involved mechanism. We suspect a defect in synthesis and secretion for p.Leu107His, p.Ala315dup and p.Pro521Leu. The mutation p.Val682Leu only affects the FVIII function while p.Ser577Tyr alters function and synthesis. The variant p.Leu2032Pro is probably a polymorphism because no alteration of the FVIII protein expression was observed in vitro. In vitro results suggest that mutations p.Ser577Tyr and p.Ala315dup could led to a severe HA in men. This study demonstrates the ability of this in vitro cellular expression model to contribute to the diagnosis strategy for female suspected of being HA carrier, without HA family history and with a novel F8 gene variation and to provide new criteria for the genetic counselling.