Comparative genomics reveals the hybrid origin of a macaque group.

Although species can arise through hybridization, compelling evidence for hybrid speciation has been reported only rarely in animals. Here, we present phylogenomic analyses on genomes from 12 macaque species and show that the fascicularis group originated from an ancient hybridization between the sinica and silenus groups ~3.45 to 3.56 million years ago. The X chromosomes and low-recombination regions exhibited equal contributions from each parental lineage, suggesting that they were less affected by subsequent backcrossing and hence could have played an important role in maintaining hybrid integrity. We identified many reproduction-associated genes that could have contributed to the development of the mixed sexual phenotypes characteristic of the fascicularis group. The phylogeny within the silenus group was also resolved, and functional experimentation confirmed that all extant Western silenus species are susceptible to HIV-1 infection. Our study provides novel insights into macaque evolution and reveals a hybrid speciation event that has occurred only very rarely in primates.

Development and validation of a novel porcine bile duct dilation model for EUS training.

Background and study aims Image-guided minimally invasive techniques have transformed the management of malignant and benign bile duct obstructions. These evolving techniques are being widely adopted and applied and hands-on training using high quality models is required to improve the proficiency of practitioners. This experimental study aimed to validate an in vivo porcine model created to simulate bile duct dilation for interventional endoscopic ultrasound (EUS) hands-on training curriculums. Materials and methods Thirty-six porcine models were involved and the procedures were performed in an experimental hybrid operating room under general anesthesia. Animals underwent endoscopic duodenal papilla clipping with several hemostatic metallic clips. After a survival period of 24 to 48 hours, the models with effective intrahepatic and extrahepatic bile duct dilatation were included in the hands-on training. Trainees and faculty were given structured evaluations of the model realism and usefulness. Results Extrahepatic bile duct and gallbladder dilation was achieved in all 36 of the models, and in 11 of the 36 models, a treatable intrahepatic duct dilatation was achieved. During the hands-on training, EUS-guided biliary drainage, EUS-guided transgastric gallbladder drainage, and EUS through-the-needle microbiopsy forceps procedures were feasible. Overall, 75 % of the experts and trainees evaluated the training as excellent. Conclusions We present a minimally invasive, reliable and time- effective model of extrahepatic dilation suitable for interventions. The model was less effective for intrahepatic ducts, which should be considered if intrahepatic biliary dilation is required for training.

Design and validation of a therapeutic EUS training program using a live animal model: Taking training to the next level.

Background and Objectives: EUS has evolved into a therapeutic modality for gastrointestinal disorders. Simulators, ex vivo models, and phantoms are the current teaching methods for therapeutic EUS (TEUS). We create and evaluate a high-fidelity simulated live animal model (HiFi SAM) for teaching endoscopists TEUS. Materials and Methods: Designing a curriculum that uses HiFi SAM and enables trainees to perform realistic procedures with expert mentors. Results: Twenty-seven trainees participated in a 3-day program with 6 h of theoretical and 14 h of hands using life HiFi SAM. Eighteen experts participated. Twenty-two (20-25) TEUS were defined for each HiFi SAM, and 616 were performed in all. Of 616/264 (43%) were evaluated with a mean of 88 per course (ranging between 80 and 95). Ninety-one percent (240/264) of the procedures were completed successfully. In 24, success was not achieved due to technical and/or model problems. Student rating of HiFi SAM was: 71% excellent rating (scale 8-10) and 95% excellent/good. The HiFi SAM procedure evaluation was (scale 1-5): fine-needle biopsy: 4.79, radiofrequency: 4.76, common bile duct and gallbladder drainage: 4.75, cystic drainages: 4.72, neurolysis: 4.55, microbiopsy: 4.50, and hepatogastric drainage: 4.04, with an overall satisfaction rate of 4.56 (91%). A short survey showed: 83% would recommend absolutely (17% most likely), 33% think that ITEC training was sufficient for their practice, and 66% would like additional training, especially more practice in specific techniques rather than more clinical case discussion. Regarding impact on their practice, 66% of the trainees started a new procedure and/or noted improvement in previous ones. Conclusion: HiFi SAM is a complex model; however, experts and trainees are satisfied with the training this new curriculum provided.

Publisher Correction: Lipidome determinants of maximal lifespan in mammals.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Cestode infections in non-human primates suggest the existence of zoonotic cycles in the area surrounding the Strasbourg primatology center.

BACKGROUND: Several cases of infections due to Echinococcus multilocularis, Taenia martis and Taenia crassiceps were recently described in various species of captive non-human primates (NHPs) harbored in the Strasbourg Primate Center (SPC). Furthermore, one of the first cases of human cysticercosis due to T. martis was described in the Strasbourg region. These data suggest the existence of zoonotic cycles of tapeworm infections in the direct environment of the SPC. The aim of our study was to assess the prevalence of larval cestode infections among intermediate and definitive hosts in the close neighborhood of the center. We analyzed carnivore mammal fecal samples as well as rodent carcasses, collected inside or near the SPC, using PCR. Furthermore, we performed serology for Echinococcus spp. and Taenia spp. on NHP sera. RESULTS: We found that 14.5% (95% CI [8.6; 20.4]) of 138 carnivore feces were positive for E. multilocularis-DNA, as well as 25% (95% CI [5.5; 57.2]) of 12 rodent carcasses, and 5.1% (95% CI [1.4; 8.7]) for T. martis or T. crassiceps. Of all NHPs tested, 10.1% (95% CI [3.8; 16.4]) were seropositive for Echinococcus spp. and 8.2% (95% CI [1.3; 15.1]) for Taenia spp. CONCLUSIONS: Our data support the existence of zoonotic cycles of larval cestode infections in the direct environment of the primatology center affecting NHPs harbored in the SPC, potentially threatening the human population living in this area. Since this zoonotic risk is borne by local wildlife, and given the severity of these infections, it seems necessary to put in place measures to protect captive NHPs, and further studies to better assess the risk to human populations.

Lipidome determinants of maximal lifespan in mammals.

Maximal lifespan of mammalian species, even if closely related, may differ more than 10-fold, however the nature of the mechanisms that determine this variability is unresolved. Here, we assess the relationship between maximal lifespan duration and concentrations of more than 20,000 lipid compounds, measured in 669 tissue samples from 6 tissues of 35 species representing three mammalian clades: primates, rodents and bats. We identify lipids associated with species' longevity across the three clades, uncoupled from other parameters, such as basal metabolic rate, body size, or body temperature. These lipids clustered in specific lipid classes and pathways, and enzymes linked to them display signatures of greater stabilizing selection in long-living species, and cluster in functional groups related to signaling and protein-modification processes. These findings point towards the existence of defined molecular mechanisms underlying variation in maximal lifespan among mammals.

Modes of transmission and genetic diversity of foamy viruses in a Macaca tonkeana colony.

BACKGROUND: Foamy viruses are exogenous complex retroviruses that are highly endemic in several animal species, including monkeys and apes, where they cause persistent infection. Simian foamy viral (SFV) infection has been reported in few persons occupationally exposed to non-human primates (NHP) in zoos, primate centers and laboratories, and recently in few hunters from central Africa. Most of the epidemiological works performed among NHP populations concern cross-sectional studies without long-term follow-up. Therefore, the exact timing and the modes of transmission of SFVs remain not well known, although sexual and oral transmissions have been suspected. We have conducted a longitudinal study in a free-breeding colony of Macaca tonkeana in order (1) to determine the prevalence of the infection by foamy viruses, (2) to characterize molecularly the viruses infecting such animals, (3) to study their genetic variability overtime by long-term follow-up of several DNA samples in a series of specific animals, and (4) to get new insights concerning the timing and the modes of SFVs primary infection in these monkeys by combining serology and molecular means, as well as studies of familial structures and long-term behavioral observations. RESULTS/CONCLUSION: We first demonstrated that this colony was highly endemic for SFVs, with a clear increase of seroprevalence with age. Only 4.7% of immatures, and 43,7% of sub-adults were found seropositive, while 89.5% of adults exhibited antibodies directed against SFV. We further showed that 6 different strains of foamy viruses (exhibiting a very low intra-strain and overtime genetic variability in the integrase gene) are circulating within this group. This suggests a possible infection by different strains within an animal. Lastly, we provide strong evidence that foamy viruses are mostly acquired through severe bites, mainly in sub-adults or young adults. Most cases of seroconversion occur after 7 years of age; from this age individuals competed for access to sexual partners, thus increasing the likelihood of being wounded. Furthermore, all the serological and molecular data, obtained in this free-breeding colony, argue against a significant transmission of SFVs from mother or father to infants as well as between siblings.

Molecular and serological evidence of Pneumocystis circulation in a social organization of healthy macaques (Macaca fascicularis).

Simian populations represent valuable models for understanding the epidemiology of human pneumocystosis. The present study aims to describe the circulation of Pneumocystis organisms within a social organization of healthy crab-eating macaques (Macaca fascicularis) living in a natural setting in France. Animals were followed for up to 2 years. Deep nasal swab and blood samples were collected monthly from each animal under general anaesthesia. Environmental air was sampled for a 1 week period every month in the park where the macaques dwelt. Pneumocystis DNA was detected by nested-PCR of mitochondrial large subunit rRNA (mtLSU) gene in nasal swab and air samples. Anti-Pneumocystis IgG antibodies were detected in serum samples by indirect immuno-fluorescence assay. Pneumocystis DNA was detected in 168 of 500 swab samples examined (33.6 %). The number of macaques with detectable Pneumocystis DNA was highly variable from one month to another. Positive detection of Pneumocystis DNA was not related to the detection of serum anti-Pneumocystis antibody. During the second year of the study, Pneumocystis DNA was amplified more frequently from unweaned macaques than from adults or subadults. The mtLSU sequence showed marked polymorphism with eight Pneumocystis sequence types representing two distinct groups. On the whole, a constant and intensive circulation of Pneumocystis organisms within the community was observed. However, the implication of the various members of the colony was probably different and several levels of colonization by Pneumocystis may occur in immunocompetent macaques.

Phylogenetic relationships among Pneumocystis from Asian macaques inferred from mitochondrial rRNA sequences.

The presence of Pneumocystis organisms was detected by nested-PCR at mitochondrial large subunit (mtLSU) rRNA gene in 23 respiratory samples from Asian macaques representing two species: Macaca mulatta and M. fascicularis. A very high level of sequence heterogeneity was detected with 18 original sequence types. Two genetic groups of Pneumocystis could be distinguished from the samples. Within each group, the extent of genetic divergence was low (2.5+/-1.4% in group 1 and 2.3+/-1.7% in group 2). Genetic divergences were systematically higher when macaque-derived sequence types were compared with Pneumocystis mtLSU sequences from other primate species (from 5.3+/-2.7% to 19.3+/-3.0%). The two macaque-derived groups may be considered as distinct Pneumocystis species. Surprisingly, these Pneumocystis species were recovered from both M. mulatta and M. fascicularis suggesting that host-species restriction may not systematically occur in the genus Pneumocystis. Alternatively, these observations question about the species concept in macaques.

Influence of climatic factors on Pneumocystis carriage within a socially organized group of immunocompetent macaques (Macaca fascicularis).

As monkeys-derived Pneumocystis is closely related to P. jirovecii, simian populations should be considered as valuable models for the understanding of the epidemiology of human pneumocystosis. In the present study, the impact of environmental factors on the carriage of Pneumocystis was evaluated in socially organized group of immunocompetent macaques (Macaca fascicularis). The tribe, maintained in partial release at the Primatology Center of Strasbourg in France, comprised 29 animals at the end of the study. From December 2000 to November 2002, deep nasal swab samples were collected monthly from each animal under general anaesthesia. The presence of Pneumocystis DNA was assessed by nested PCR of mtLSU rRNA gene. No case of pneumocystosis was reported during the study. Pneumocystis DNA was detected in 166 out of 481 swab samples examined (34.5%). The number of macaques with detectable Pneumocystis DNA was highly variable from one month to another. However, Pnemocystis carriage was clearly correlated to the mean precipitation rates.