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Finite Element Analysis (FEA) of multilayer structures using plates and shells is not able to quantify the singular stresses distribution, especially the local overstresses near the boundaries. This critical design parameter is taken into account by 3D FEA models, which are not used for systematic computations due to a very long calculation time. The software CLEOPS (Composites Local Effects Of Plates and Shells) is developed by MEDYSYS (MEchanics and DYnamics of SYStems) to address this problem for composite laminates and their bonded assemblies involved in aerospace or defense industry. It is used as a postprocessor of Finite Element computations on plates and shells to calculate the 3D stresses within multilayer structures subjected to mechanical plane or bending loadings. The edge effects are computed at the mesoscale based on a semi-analytical asymptotic method with one-dimensional finite elements in the through-thickness direction. The software includes quadratic failure criteria in order to evaluate the delamination initiation and anticipate whether the laminates can withstand a fatigue load. The calculation of the stiesses distribution near the edges of multilayer structures and the fatigue delamination are key issues developed in this article. Results provided by CLEOPS are compared to 3D FEA results. [ABSTRACT FROM AUTHOR]

Toxoplasmosis is characterized by a complex epidemiology. The risk of infection for humans depends on their contact with infective oocysts in a contaminated environment and on the amount of tissue cysts located within consumed meat. Unfortunately, the prevalence of tissue cysts is largely unknown for game species. Although herbivorous game species are a source of infection for humans, the level of infection found in wildlife can also be used to estimate environmental contamination. The aim of this study was to estimate the prevalence of Toxoplasma gondii infection and analyze its temporal dynamics in one population of chamois ( Rupicapra rupicapra), one of mouflon ( Ovis gmelini musimon), and two of roe deer ( Capreolus capreolus) in France, surveyed during a period of 6 to 28 years. Taking into account individual risk factors, we specifically analyzed the relationship between T. gondii prevalence and meteorological conditions that may influence oocyst survival. Serum samples from 101 chamois, 143 mouflons, and 1155 roe deer were tested for antibodies against T. gondii using the modified agglutination test (MAT), an enzyme-linked immunosorbent assay (ELISA) assay, or both. Using MAT with a threshold of 1:6, seroprevalence was 14.7% in mouflon, 16.8% in chamois, and 43.7% in roe deer. In mouflon and roe deer, seroprevalence was positively correlated with age and/or body mass, in accordance with the hypothesis that antibodies have long-term persistence. In roe deer, seropositivity differed between the two populations and changed linearly over time between 1983 and 2010, increasing by a factor 1.75 every 10 years. Moreover, in this species, the highest prevalences were found during dry and cold years or during warm and moist years, depending on the population. Our results suggest that the risk for people to acquire infection through game meat increases over time, but with high variability according to the population of origin and meteorological conditions of the year. [ABSTRACT FROM AUTHOR]

Microbial infections that affect reproduction are poorly studied in wildlife because reproductive disorders usually go unnoticed. However, such infections are a major concern in domestic ungulates, which raises the question of their influence on reproductive success and population dynamics of wild ungulates. Three bacterial abortive infections are frequent in domestic ruminants: salmonellosis caused by Salmonella enterica serovar Abortusovis, enzootic abortion caused by Chlamydophila abortus, and Q fever caused by Coxiella burnetii. They induce abortions and neonatal mortality in sheep (Ovis aries L., 1758), goat (Capra hircus L., 1758), and cattle (Bos taurus L., 1758). However, little information is known about these bacteria in wild ungulates, particularly in mountain ungulates that may share alpine pastures with infected domestic ruminants. We investigated the relationship between female serological status against Salmonella, Chlamydophila, and Coxiella and her reproductive success. From 1986 to 2003, the reproductive and serological statuses of 125 female chamois (Rupicapra rupicapra (L., 1758)) aged 2-10 years were available. Reproductive success was the lowest for 2-year-old females and for females born at the highest density. Moreover, we showed for the first time in a wild ungulate population that females with high titer in antibodies against Salmonella experienced a decrease in their reproductive success. Titers in antibodies against Chlamydophila and Coxiella were not related to the reproductive success of female chamois. [ABSTRACT FROM AUTHOR]

Abstract: Outbreaks of a previously unrecorded disease have recently affected Pyrenean chamois (Rupicapra pyrenaica pyrenaica) populations across the mountain range. A pestivirus was hypothesized to be the cause of this emerging disease and this type of virus can cross the species barrier and be transmitted to or from wildlife. Using an epidemiological survey conducted from 1995 to 2004 at Orlu, France, we characterized the virus and analyzed its transmission. A phylogenetic analysis of viral sequences and virus neutralization tests showed that the virus belonged to the newly described border disease virus-4 group. The increase of seroprevalence with age indicated that infection can occur at any age and resulted in lifelong immunity. Overall, 70.3% of 323 samples were positive for anti-p80 antibodies and 10.2% of 167 samples showed viremia, as demonstrated by either positive ELISA antigen test or RT-PCR. Infection has thus been widespread in this population since 1995, whereas no mass mortality or clinical signs have been observed. Incidence and seroprevalence varied seasonally and according to number of individuals aged less than 2 years old in the population, so viral transmission was dependent on host population age structure. We propose that the virus is now endemic in this population and is likely detrimental for reproduction and juveniles. Further investigation is needed to estimate the impact of pestivirus on host population dynamics and the risk of cross-transmission to farm animals. [Copyright &y& Elsevier]

Dental care unit waterlines (DCUWs) consist of complex networks of thin tubes that facilitate the formation of microbial biofilms. Due to the predilection toward a wet environment, strong adhesion, biofilm formation, and resistance to biocides, Pseudomonas aeruginosa, a major human opportunistic pathogen, is adapted to DCUW colonization. Other nonfermentative Gram-negative bacilli, such as members of the genus Achromobacter, are emerging pathogens found in water networks. We reported the 6.5-year dynamics of bacterial contamination of waterlines in a dental health care center with 61 dental care units (DCUs) connected to the same water supply system. The conditions allowed the selection and the emergence of clones of Achromobacter sp. and P. aeruginosa characterized by multilocus sequence typing, multiplex repetitive elements-based PCR, and restriction fragment length polymorphism in pulsed-field gel electrophoresis, biofilm formation, and antimicrobial susceptibility. One clone of P. aeruginosa and 2 clones of Achromobacter sp. colonized successively all of the DCUWs: the last colonization by P. aeruginosa ST309 led to the closing of the dental care center. Successive dominance of species and clones was linked to biocide treatments. Achromobacter strains were weak biofilm producers compared to P. aeruginosa ST309, but the coculture of P. aeruginosa and Achromobacter enhanced P. aeruginosa ST309 biofilm formation. Intraclonal genomic microevolution was observed in the isolates of P. aeruginosa ST309 collected chronologically and in Achromobacter sp. clone A. The contamination control was achieved by a complete reorganization of the dental health care center by removing the connecting tubes between DCUs. [ABSTRACT FROM AUTHOR]

Dental care unit waterlines (DCUWs) consist of complex networks of thin tubes that facilitate the formation of microbial biofilms. Due to the predilection toward a wet environment, strong adhesion, biofilm formation, and resistance to biocides, Pseudomonas aeruginosa, a major human opportunistic pathogen, is adapted to DCUW colonization. Other nonfermentative Gram-negative bacilli, such as members of the genus Achromobacter, are emerging pathogens found in water networks. We reported the 6.5-year dynamics of bacterial contamination of waterlines in a dental health care center with 61 dental care units (DCUs) connected to the same water supply system. The conditions allowed the selection and the emergence of clones of Achromobacter sp. and P. aeruginosa characterized by multilocus sequence typing, multiplex repetitive elements-based PCR, and restriction fragment length polymorphism in pulsed-field gel electrophoresis, biofilm formation, and antimicrobial susceptibility. One clone of P. aeruginosa and 2 clones of Achromobacter sp. colonized successively all of the DCUWs: the last colonization by P. aeruginosa ST309 led to the closing of the dental care center. Successive dominance of species and clones was linked to biocide treatments. Achromobacter strains were weak biofilm producers compared to P. aeruginosa ST309, but the coculture of P. aeruginosa and Achromobacter enhanced P. aeruginosa ST309 biofilm formation. Intraclonal genomic microevolution was observed in the isolates of P. aeruginosa ST309 collected chronologically and in Achromobacter sp. clone A. The contamination control was achieved by a complete reorganization of the dental health care center by removing the connecting tubes between DCUs. [ABSTRACT FROM AUTHOR]

Peridontal and peri-implant diseases have a lot of similarities, in particular their bacterial origin, caracterized by specific bacteria. After describing the definition of the diseases, we continue with the bacteriology of the disease and their pathogeny mechanism. In this article we also try to conclude on the current anti infections therapies. Finally, we are going to precise (with a pretiminary clinical study) the use of ozon, gaz which is know and used in medecine (for his bactericidal propertises) since the beginning of the 20th century. [ABSTRACT FROM AUTHOR]

Avulsion's suites have been widely described, resulting in bone loss even more important than the cortex are fine. The post extractionnal bone loss occurs very rapidly and will continue for several months, leading to unfavorable aesthetic and functional situations pre implant. So it is before it happens that we must intervene. Guided bone regeneration may be implemented at the stage of avulsion by the use of resorbable membranes, allowing the preservation of bone volume of good quality. Clinical studies help to determine the impact sites, and patients about the effectiveness and predictability of guided bone regeneration. The objective is to optimize the selection of cases and to propose a therapeutic choice in terms of development of the protocol guided bone regeneration. [ABSTRACT FROM AUTHOR]

An efficient immunity is necessary for host survival, but entails energetic costs. When energy is limited, immunocompetence and body condition should co-vary positively among individuals and, depending on body condition, individuals should allocate more either in innate immunity or in adaptive response. We tested whether immune phenotype depends on body condition in large mammals, using data from two contrasted populations of roe deer Capreolus capreolus in France. Roe deer living at Chizé, a forest with poor habitat quality, were expected to show lower values for body condition and immune parameters than roe deer at Trois Fontaines, a forest with high habitat quality. From 285 blood samples collected between December 2009 and March 2011, we measured seven metabolic parameters and ten immunological parameters. A Principal Component Analysis showed that all indicators of body condition co-varied positively and were lowest at Chizé. Several immunological indicators correlated to body condition and differed between Trois Fontaines and Chizé. However, high body condition was not associated to a high average level of immunocompetence, but instead to high levels of indicators of acute inflammatory innate response, while low body condition was associated to high levels of monocytes and lymphocytes, possibly reflecting adaptive immunity. Limited data suggest that the difference between populations was not related to the presence of specific parasite species, however parasite exposure and stress have to be investigated to gain a more complete understanding of the determinants of immunity. [ABSTRACT FROM AUTHOR]

The bacterium Mycoplasma agalactiae is responsible for contagious agalactia (CA) in small domestic ruminants, a syndrome listed by the World Organization for Animal Health and responsible for severe damage to the dairy industry. Recently, we frequently isolated this pathogen from lung lesions of ibexes during a mortality episode in the French Alps. This situation was unusual in terms of host specificity and tissue tropism, raising the question of M. agalactiae emergence in wildlife. To address this issue, the ibex isolates were characterized using a combination of approaches that included antigenic profiles, molecular typing, optical mapping, and whole-genome sequencing. Genome analyses showed the presence of a new, large prophage containing 35 coding sequences (CDS) that was detected in most but not all ibex strains and has a homolog in Mycoplasma conjunctivae, a species causing keratoconjunctivitis in wild ungulates. This and the presence in all strains of large integrated conjugative elements suggested highly dynamic genomes. Nevertheless, M. agalactiae strains circulating in the ibex population were shown to be highly related, most likely originating from a single parental clone that has also spread to another wild ungulate species of t he same geographical area, the chamois. These strains clearly differ from strains described in Europe so far, including those found nearby, before CA eradication a few years ago. While M. agalactiae pathogenicity in ibexes remains unclear, our data showed the emergence of atypical strains in Alpine wild ungulates, raising the question of a role for the wild fauna as a potential reservoir of pathogenic mycoplasmas. [ABSTRACT FROM AUTHOR]

Bluetongue virus (BTV) is a Culicoides-borne pathogen infecting both domestic and wild ruminants. In Europe, the Red Deer (Cervus elaphus) (RD) is considered a potential BTV reservoir, but persistent sylvatic cycle has not yet been demonstrated. In this paper, we explored the dynamics of BTV1 and BTV8 serotypes in the RD in France, and the potential role of that species in the re-emergence of BTV8 in livestock by 2015 (i.e., 5 years after the former last domestic cases). We performed 8 years of longitudinal monitoring (2008–2015) among 15 RD populations and 3065 individuals. We compared Culicoides communities and feeding habits within domestic and wild animal environments (51,380 samples). Culicoides diversity (>30 species) varied between them, but bridge-species able to feed on both wild and domestic hosts were abundant in both situations. Despite the presence of competent vectors in natural environments, BTV1 and BTV8 strains never spread in RD along the green corridors out of the domestic outbreak range. Decreasing antibody trends with no PCR results two years after the last domestic outbreak suggests that seropositive young RD were not recently infected but carried maternal antibodies. We conclude that RD did not play a role in spreading or maintaining BTV in France. [ABSTRACT FROM AUTHOR]