Planum temporale asymmetry in newborn monkeys predicts the future development of gestural communication's handedness.

The planum temporale (PT), a key language area, is specialized in the left hemisphere in prelinguistic infants and considered as a marker of the pre-wired language-ready brain. However, studies have reported a similar structural PT left-asymmetry not only in various adult non-human primates, but also in newborn baboons. Its shared functional links with language are not fully understood. Here we demonstrate using previously obtained MRI data that early detection of PT left-asymmetry among 27 newborn baboons (Papio anubis, age range of 4 days to 2 months) predicts the future development of right-hand preference for communicative gestures but not for non-communicative actions. Specifically, only newborns with a larger left-than-right PT were more likely to develop a right-handed communication once juvenile, a contralateral brain-gesture link which is maintained in a group of 70 mature baboons. This finding suggests that early PT asymmetry may be a common inherited prewiring of the primate brain for the ontogeny of ancient lateralised properties shared between monkey gesture and human language.

Successful Treatment of Captive Common Marmosets (Callithrix jacchus) Infested with Common Cat Fleas (Ctenocephalides felis) by Using Topical Imidacloprid and Environmental Control Measures.

Fleas are ectoparasites affecting many animal species but reports in captive nonhuman primates are rare and mainly concern pet monkeys. Moreover, to the authors' knowledge, a detailed report on marmosets is not known at present. This case describes the clinical signs, diagnosis, treatment and follow-up of a flea infestation by Ctenocephalides felis in a captive colony of common marmosets. Fleas, flea feces and skin lesions were identified on two animals during annual health screening. Subsequently, the entire colony was examined, and nearly half of the colony showed signs of infestation. Consequently, treatment was initiated for the entire colony and the environment. Animals received two topical administrations of imidacloprid (5 mg for animals <200 g and 10 mg for animals weighing >200 g) three weeks apart, and their enclosures were decontaminated using vaporizers containing permethrin, piperonyl butoxide, and pyriproxyfen. Subsequently, skin lesions were resolved and no evidence of fleas were noticed. No side effects of the treatment were observed. Stray cats were identified as the source of the infestation. Their access to the animal-related rooms was stopped. No reinfestation has been reported for 3 years. The topical application of imidacloprid appeared effective with no adverse events occurring, so may be appropriate for use in other non-human primates.

A wear model to predict damage of reconstructed ACL.

Impingement with surrounding tissues is a major cause of failure of anterior cruciate ligament reconstruction. However, the complexity of the knee kinematics and anatomical variations make it difficult to predict the occurrence of contact and the extent of the resulting damage. Here we hypothesise that a description of wear between the reconstructed ligament and adjacent structures captures the in vivo damage produced with physiological loadings. To test this, we performed an in vivo study on a sheep model and investigated the role of different sources of damage: overstretching, excessive twist, excessive compression, and wear. Seven sheep underwent cranial cruciate ligament reconstruction using a tendon autograft. Necropsy observations and pull-out force measurements performed postoperatively at three months showed high variability across specimens of the extent and location of graft damage. Using 3D digital models of each stifle based on X-ray imaging and kinematics measurements, we determined the relative displacements between the graft and the surrounding bones and computed a wear index describing the work of friction forces underwent by the graft during a full flexion-extension movement. While tensile strain, angle of twist and impingement volume showed no correlation with pull-out force (ρ = -0.321, p = 0.498), the wear index showed a strong negative correlation (r = -0.902, p = 0.006). Moreover, contour maps showing the distribution of wear on the graft were consistent with the observations of damage during the necropsy. These results demonstrate that wear is a good proxy of graft damage. The proposed wear index could be used in implant design and surgery planning to minimise the risk of implant failure. Its application to sheep can provide a way to increase preclinical testing efficiency.

New 5-mm laparoscopic pneumodissector device to improve laparoscopic dissection: an experimental study of its safety in a swine model.

BACKGROUND: To improve the laparoscopic surgical dissection, the aim of the study was to assess the safety of burst of high-pressure CO2 using a 5-mm laparoscopic pneumodissector (PD) operating at different flow rates and for different operating times regarding the risk of gas embolism (GE) in a swine model. METHODS: The first step was to define the settings use of the PD device ensuring no GE. Successive procedures were conducted by laparotomy: cholecystectomy, the PD was placed 10 mm deep in the liver and the PD was directly introduced into the lumen of the inferior vena cava. Different PD flow rates of 5, 10, and 15 mL/s were used. The second step was to assess the safety of the device (PD group) during a laparoscopic dissection task (cystic and hepatic pedicles dissection, cholecystectomy and right nephrectomy) in comparison with the use of a standard laparoscopic hook device (control group). PD flow rate was 10 mL/s and consecutive burst of high-pressure CO2 was delivered for 3-5 s. RESULTS: In the first step (n = 17 swine), no GE occurred during cholecystectomy regardless of the PD flow rate used. When the PD was placed in the liver or into the inferior vena cava, no severe or fatal GE occurred when a burst of high-pressure CO2 was applied for 3 or 5 s with PD flow rates of 5 and 10 mL/s. In the second step (PD group, n = 10; control group, n = 10), no GE occurred in the PD group. The use of the PD did not increase operative time or blood loss. The quality of the dissection was significantly improved compared to the control group. CONCLUSIONS: The 5-mm laparoscopic PD appears to be free from CO2 GE risk when consecutive bursts of high-pressure CO2 are delivered for 3-5 s with a flow rate of 10 mL/s.