Effects of Genetic Background,Gender, and Early Environmental Factors on Isolation-Induced Ultrasonic Calling in Mouse Pups: An Embryo-Transfer Study

Infant rodents emit ultrasonic vocalizations when isolated from dam and littermates. Due to the context of their occurrence and the well described bidirectional modulation by substances known for their capability to influence emotionality, it was postulated that such calls reflect a negative affective state akin anxiety. Comparative studies observed pronounced differences in calling behavior between strains, which were paralleled by differences in maternal care. Therefore, it was recently hypothesized that early environmental factors may have strong impact on call production. Here, the relative contributions of genetic background, gender, and early environmental factors on calling behavior in C57BL/6JOlaHsd and C57BL/6NCrl were studied by using an embryo-transfer procedure. The results show that these sub-strains differ in the amount of calling and specific call features, like call frequency and amplitude. The embryo-transfer procedure indicated that the observed differences in the amount of ultrasonic calling are dependent on the dyadic interaction between mother and pup. Conversely, call features were primarily dependent on the genotype of the pup. Thus, call frequency and frequency modulation were solely dependent on the pup, i.e. its genotype and gender. However, there was one exception, namely call amplitude, which was solely dependent on the genotype of the mother, i.e. on early environmental factors. Furthermore, it was shown that particularly changes in call amplitude might be of high functional relevance, since a sub-strain dependent preference towards pups emitting calls with high amplitudes was observed. In total, it can be concluded that both genomic and nongenomic factors can tune calling behavior in mouse pups.     

Application of the adverse outcome pathway framework to genotoxic modes of action

In May 2017, the Health and Environmental Sciences Institute's Genetic Toxicology Technical Committee hosted a workshop to discuss whether mode of action (MOA) investigation is enhanced through the application of the adverse outcome pathway (AOP) framework. As AOPs are a relatively new approach in genetic toxicology, this report describes how AOPs could be harnessed to advance MOA analysis of genotoxicity pathways using five example case studies. Each of these genetic toxicology AOPs proposed for further development includes the relevant molecular initiating events, key events, and adverse outcomes (AOs), identification and/or further development of the appropriate assays to link an agent to these events, and discussion regarding the biological plausibility of the proposed AOP. A key difference between these proposed genetic toxicology AOPs versus traditional AOPs is that the AO is a genetic toxicology endpoint of potential significance in risk characterization, in contrast to an adverse state of an organism or a population. The first two detailed case studies describe provisional AOPs for aurora kinase inhibition and tubulin binding, leading to the common AO of aneuploidy. The remaining three case studies highlight provisional AOPs that lead to chromosome breakage or mutation via indirect DNA interaction (inhibition of topoisomerase II, production of cellular reactive oxygen species, and inhibition of DNA synthesis). These case studies serve as starting points for genotoxicity AOPs that could ultimately be published and utilized by the broader toxicology community and illustrate the practical considerations and evidence required to formalize such AOPs so that they may be applied to genetic toxicity evaluation schemes. Environ. Mol. Mutagen. 61:114–134, 2020. © 2019 Wiley Periodicals, Inc.     

Application of mycobacterial proteomics to vaccine design: improved protection by Mycobacterium bovis BCG prime-Rv3407 DNA boost vaccination against tuberculosis

Information from comparative proteome analysis of Mycobacterium tuberculosis and Mycobacterium bovis bacillus Calmette-Guerin (BCG) principally allows prediction of potential vaccine candidates. Thirty-six M. tuberculosis DNA vaccine candidates identified by comparative proteome analysis were evaluated in the mouse model for protection against low-dose aerosol M. tuberculosis infection. We identified the DNA vaccine candidate Rv3407 as a protective antigen and analyzed putative major histocompatibility complex class I epitopes by computational predictions and gamma interferon Elispot assays. Importantly, we discovered that the DNA vaccine Rv3407 improved the efficacy of BCG vaccination in a heterologous prime-boost vaccination protocol. Our data demonstrate the rationale of a combination of proteomics, epitope prediction, and broad screening of putative antigens for identification of novel DNA vaccine candidates. Furthermore, our experiments show that heterologous prime-boost vaccination with a defined antigen boost "on top" of a BCG primer provides superior protection against tuberculosis over vaccination with BCG alone.     

Preformed donor-reactive T cells that persist after ABO desensitization predict severe T cell-mediated rejection after living donor kidney transplantation – a retrospective study

Preformed donor-reactive T cells are relatively resistant to standard immunosuppression and account for an increased incidence of T cell-mediated rejection (TCMR) and inferior kidney allograft outcomes. We analyzed 150 living donor kidney transplant recipients (KTRs) of a first kidney allograft. Ninety-eight ABO-compatible (ABOc) and 52 ABO-incompatible (ABOi) KTRs were included. Samples were collected at 6 time points, before rituximab, before immunoadsorption and pretransplantation, at +1, +2, and +3 months posttransplantation, and donor-reactive T cells were measured by interferon-γ ELISPOT assay. Twenty of 98 ABOc (20%) and 12 of 52 ABOi KTRs (23%) showed positive pretransplant ELISPOT. Eight of 20 ABOc-KTRs (40%) with positive pretransplant ELISPOT showed TCMR, whereas 17 of 78 ABOc-KTRs (22%) with negative pretransplant ELISPOT did (P = 0.148). Seven of 12 ABOi KTRs (57%) with positive pretransplant ELISPOT showed TCMR, whereas only 3 of 40 ABOi KTRs (8%) with negative pretransplant ELISPOT did (P < 0.001). Interestingly, 6 of 7 ABOi KTRs with positive pretransplant ELISPOT that persists after ABO desensitization developed TCMR. Among 118 KTRs with negative pretransplant ELISPOT, 10 of 72 ABOc-KTRs (14%), but 0 of 46 ABOi KTRs, developed positive posttransplant ELISPOT (P = 0.006). Preformed donor-reactive T cells that persist despite ABO desensitization identify KTRs at highest risk of TCMR. Less de-novo donor-reactive T cells after ABO desensitization may account for less TCMR. Both, the use of rituximab and early initiation of calcineurin inhibitor-based maintenance immunosuppression may contribute to these findings.     

Wie balanciert sollte eine kristalloide Lösung sein?

Die Anaesthesiologie -     

Pituitary adenylate cyclase activating peptides relax human pulmonary arteries by opening of KATP and KCa channels

BACKGROUND—Pituitaryadenylate cyclase activating peptides (PACAPs) are potent endotheliumindependent dilators of human coronary arteries; however, their effectson human pulmonary arteries are unknown.
Methods—Thevasorelaxant effects of PACAP27 on human pulmonary segmental arterieswere studied and the specific potassium (K⁺) channelregulatory mechanisms in the vasorelaxant effects were tested by meansof isometric contraction experiments.
RESULTS—PACAP27produced dose dependent relaxations of 10 µM rings preconstrictedwith prostaglandin F_2α (PGF_2α ) with half maximal relaxation (IC₅₀) at 17 nM. Pretreatment of thevessels with the ATP sensitive K⁺ (K_ATP)channel blocker glibenclamide (1 µM) or with the Ca²⁺activated K⁺ (K_Ca) channel blockeriberiotoxin (100 nM) inhibited the PACAP27 induced relaxation.
Conclusions—Theseresults provide evidence that PACAPs are potent vasodilators of humanpulmonary arteries and that this relaxation might be mediated byopening of K_ATP and K_Ca channels.

     

NSF workshop report: Discovering general principles of nervous system organization by comparing brain maps across species

Efforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene‐structure‐function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system ‘maps' comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of ‘reference species' to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well‐annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies. It will also be important to develop new integrated software and database systems for cross‐species data analyses. Multidisciplinary efforts to develop such analytical tools should be supported financially. Finally, training opportunities should be created to stimulate multidisciplinary, integrative research into brain structure, function, and evolution. J. Comp. Neurol. 522:1445–1453, 2014. © 2014 Wiley Periodicals, Inc.