Hano, C. | bioRxiv Science

bioRxiv2021

{-}CardiOvascular examination in awake Orangutans (Pongo pygmaeus pygmaeus): Low-stress Echocardiography including Speckle Tracking imaging (the COOLEST method)

IntroductionCardiovascular diseases have been identified as a major cause of mortality and morbidity in Borneo orangutans (Pongo pygmaeus pygmaeus). Transthoracic echocardiography is usually performed under anesthesia in great apes, which may be stressful and risky in cardiac animals. The aim of the present pilot study was hence to develop a quick and non-stressful echocardiographic method (i.e., the COOLEST method) in awake Borneo orangutans (CardiOvascular examination in awake Orangutans: Low-stress Echocardiography including Speckle Tracking imaging) and assess the variability of corresponding variables. Materials and MethodsFour adult Borneo orangutans trained to present their chest to the trainers were involved. A total of 96 TTE examinations were performed on 4 different days by a trained observer examining each orangutans 6 times per day. Each examination included four two-dimensional views, with offline assessment of 28 variables (i.e., two-dimensional (n=12), M-mode and anatomic M-mode (n=6), Doppler (n=7), and speckle tracking imaging (n=3)), representing a total of 2,688 measurements. A general linear model was used to determine the within-day and between-day coefficients of variation. ResultsMean{+/-}SD (minimum-maximum) images acquisition duration was 3.8{+/-}1.6 minutes (1.3-6.3). All within-day and between-day coefficients of variation but one (n=55/56, 98%) were <15%, and most (51/56, 91%) were <10% including those of speckle tracking systolic strain variables (2.7% to 5.4%). DiscussionHeart morphology as well as global and regional myocardial function can be assessed in awake orangutans with good to excellent repeatability and reproducibility. ConclusionsThis non-stressful method may be used for longitudinal cardiac follow-up in awake orangutans.

zoology↗

bioRxiv2018

Salivary proteins of a gall-inducing aphid and their impact on early gene responses of susceptible and resistant host-plant genotypes

Successful plant colonization by parasites requires the circumvention of host defenses, and sometimes a reprogramming of host metabolism, mediated by effector molecules delivered into the host. Using transcriptomic and enzymatic approaches, we characterized salivary glands and saliva of Phloeomyzus passerinii, an aphid exhibiting an atypical feeding strategy. Plant genes responses to salivary extracts of P. passerinii and Myzus persicae were assessed with poplar protoplasts of a susceptible and a resistant genotype, and in a heterologous Arabidopsis system. We predict that P. passerinii secretes a highly peculiar saliva containing effectors potentially interfering with host defenses, biotic stress signaling and plant metabolism, notably phosphatidylinositol phosphate kinases which seemed specific to P. passerinii. Gene expression profiles indicated that salivary extracts of M. persicae markedly affected host defenses and biotic stress signaling, while salivary extracts of P. passerinii induced only weak responses. The effector-triggered susceptibility was characterized by downregulations of genes involved in cytokinin signaling and auxin homeostasis. This suggests that P. passerinii induces an intracellular accumulation of auxin in susceptible host genotypes, which is supported by histochemical assays in Arabidopsis. This might in turn affect biotic stress signaling and contribute to host tissue manipulation by the aphid.

ecology↗