Professional stereotypes among specialties and fields of work within the veterinary community.

BACKGROUND: Medical specialties hold varying degrees of prestige, stemming from the existence of stereotypes among them. These have been shown to lead to prejudice against specific specialists, which not only influences career choices but also affects the perception of equality among specialties. METHOD: The aim of the research was to determine the presence of stereotypes in the UK veterinary community. Using an online questionnaire, participants were asked to provide an adjective that best characterises 15 specialties, in addition to their perceptions on prestige and gender association. Word cloud analysis coupled with sentiment analysis in Python using the language processing software Natural Language Toolkit (NLTK) was used to assess sentiments with respect to the adjectives. RESULTS: There were 665 questionnaire respondents, and there was evidence of their construction of specialty-specific stereotypes. Some specialties were perceived more negatively than others, including equine general practitioners, surgeons, pathologists, dermatologists and public health veterinarians/epidemiologists. Gender bias was identified within this study, most prominently within production animal and behavioural medicine veterinarians. The most prestigious specialties were neurology, surgery and cardiology. CONCLUSION: Specialty-specific stereotypes exist within the veterinary community. Acknowledging their existence is a first step to recognising the influence they have on career choices.

Whole-Cell Patch Clamp Recordings from Oligodendrocyte Lineage Cells in Brain Slices.

The whole-cell configuration of the patch-clamp technique is widely used to study electrically active cells and passive membrane properties, as well as the properties and pharmacology of ion channels, neurotransmitter receptors, and electrogenic transporters, in almost any cell type. In the brain, in addition to neurons, oligodendrocyte precursor cells (OPCs) that give rise to myelinating oligodendrocytes (OLs) are also excitable. Electrophysiological techniques provide the main tool for the thorough investigation of the electrogenic capacity of such cell types. Although there are many published protocols for whole-cell recordings, there are very few that touch upon the electrophysiological characteristics of oligodendrocyte lineage cells. Here we provide a detailed methodology for how to acquire and analyze whole-cell recordings from excitable cells, with a focus on oligodendrocyte lineage cells. We provide a protocol on how to successfully identify OPCs and OLs in brain slices, either with the use of transgenic animal models or through morphological and electrophysiological profiling. The method described can also be easily adopted for whole-cell recordings from oligodendrocyte lineage cells in vitro.

Oligodendrocyte Progenitor Cells Become Regionally Diverse and Heterogeneous with Age.

Oligodendrocyte progenitor cells (OPCs), which differentiate into myelinating oligodendrocytes during CNS development, are the main proliferative cells in the adult brain. OPCs are conventionally considered a homogeneous population, particularly with respect to their electrophysiological properties, but this has been debated. We show, by using single-cell electrophysiological recordings, that OPCs start out as a homogeneous population but become functionally heterogeneous, varying both within and between brain regions and with age. These electrophysiological changes in OPCs correlate with the differentiation potential of OPCs; thus, they may underlie the differentiational differences in OPCs between regions and, likewise, differentiation failure with age.

Gene Editing in Rat Embryonic Stem Cells to Produce In Vitro Models and In Vivo Reporters.

Rat embryonic stem cells (ESCs) offer the potential for sophisticated genome engineering in this valuable biomedical model species. However, germline transmission has been rare following conventional homologous recombination and clonal selection. Here, we used the CRISPR/Cas9 system to target genomic mutations and insertions. We first evaluated utility for directed mutagenesis and recovered clones with biallelic deletions in Lef1. Mutant cells exhibited reduced sensitivity to glycogen synthase kinase 3 inhibition during self-renewal. We then generated a non-disruptive knockin of dsRed at the Sox10 locus. Two clones produced germline chimeras. Comparative expression of dsRed and SOX10 validated the fidelity of the reporter. To illustrate utility, live imaging of dsRed in neonatal brain slices was employed to visualize oligodendrocyte lineage cells for patch-clamp recording. Overall, these results show that CRISPR/Cas9 gene editing technology in germline-competent rat ESCs is enabling for in vitro studies and for generating genetically modified rats.

Surpassing light-induced cell damage in vitro with novel cell culture media.

Light is extensively used to study cells in real time (live cell imaging), separate cells using fluorescence activated cell sorting (FACS) and control cellular functions with light sensitive proteins (Optogenetics). However, photo-sensitive molecules inside cells and in standard cell culture media generate toxic by-products that interfere with cellular functions and cell viability when exposed to light. Here we show that primary cells from the rat central nervous system respond differently to photo-toxicity, in that astrocytes and microglia undergo morphological changes, while in developing neurons and oligodendrocyte progenitor cells (OPCs) it induces cellular death. To prevent photo-toxicity and to allow for long-term photo-stimulation without causing cellular damage, we formulated new photo-inert media called MEMO and NEUMO, and an antioxidant rich and serum free supplement called SOS. These new media reduced the detrimental effects caused by light and allowed cells to endure up to twenty times more light exposure without adverse effects, thus bypassing the optical constraints previously limiting experiments.

Early maturation and distinct tau pathology in induced pluripotent stem cell-derived neurons from patients with MAPT mutations.

Tauopathies, such as Alzheimer's disease, some cases of frontotemporal dementia, corticobasal degeneration and progressive supranuclear palsy, are characterized by aggregates of the microtubule-associated protein tau, which are linked to neuronal death and disease development and can be caused by mutations in the MAPT gene. Six tau isoforms are present in the adult human brain and they differ by the presence of 3(3R) or 4(4R) C-terminal repeats. Only the shortest 3R isoform is present in foetal brain. MAPT mutations found in human disease affect tau binding to microtubules or the 3R:4R isoform ratio by altering exon 10 splicing. We have differentiated neurons from induced pluripotent stem cells derived from fibroblasts of controls and patients with N279K and P301L MAPT mutations. Induced pluripotent stem cell-derived neurons recapitulate developmental tau expression, showing the adult brain tau isoforms after several months in culture. Both N279K and P301L neurons exhibit earlier electrophysiological maturation and altered mitochondrial transport compared to controls. Specifically, the N279K neurons show abnormally premature developmental 4R tau expression, including changes in the 3R:4R isoform ratio and AT100-hyperphosphorylated tau aggregates, while P301L neurons are characterized by contorted processes with varicosity-like structures, some containing both alpha-synuclein and 4R tau. The previously unreported faster maturation of MAPT mutant human neurons, the developmental expression of 4R tau and the morphological alterations may contribute to disease development.

Clever glia.

Twenty years ago glial cells were shown to contribute to neuronal information processing, instead of merely supporting neuronal function, thus challenging the century old neuron doctrine. Due to the lack of appropriate experimental models, however, determining the role of glia in higher brain function and disease has been hampered. In a recent paper, Han and colleagues transplanted human glial progenitor cells into mice; not only does this study pave the way for generations of excellent models to study the physiology and pathophysiology of human glial cells, especially in the age of induced pluripotent stem cells, but more importantly it further challenges the neuron doctrine, since the human-glia transplanted mice turned into better learners. So, are glial cells the ones we owe our intelligence to after all?