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Contents The aim of this study was to investigate how acute insulin-induced hypoglycaemia (IIH) alters the activity of cells containing oestradiol receptor α (ER α) or somatostatin (SST) in the arcuate nucleus (ARC) and ventromedial nucleus (VMN), and ER α cells in the medial preoptic area (m POA) of intact ewes. Follicular phases were synchronized with progesterone vaginal pessaries. Control animals were killed at 0 h or 31 h (n = 5 and 6, respectively) after progesterone withdrawal (PW; time zero). At 28 h, five other animals received insulin (INS; 4 iu/kg) and were subsequently killed at 31 h. Hypothalamic sections were immunostained for ER α or SST each with c-Fos, a marker of neuronal transcriptional activation. Insulin did not alter the percentage of activated ER α cells in the ARC; however, it appeared visually that two insulin-treated animals (INS responders, with no LH surge) had an increase in the VMN (from 32 to 78%) and a decrease in the m POA (from 40 to 12%) compared to no increase in the two INS non-responders (with an LH surge). The percentage of activated SST cells in the ARC was greater in all four insulin-treated animals (from 10 to 60%), whereas it was visually estimated that activated SST cells in the VMN increased only in the two insulin responders (from 10 to 70%). From these results, we suggest that IIH stimulates SST activation in the ARC as part of the glucose-sensing mechanism but ER α activation is unaffected in this region. We present evidence to support a hypothesis that disruption of the GnRH/LH surge may occur in insulin responders via a mechanism that involves, at least in part, SST cell activation in the VMN along with decreased ER α cell activation in the m POA. [ABSTRACT FROM AUTHOR]

Contents The present study examines the involvement of GABAA or B receptors in gonadotrophin-releasing hormone (GnRH) release in vitro and determines whether oestradiol modulates γ-aminobutyric acid (GABA)–GnRH interaction. Within 10 min after ewe killing, hypothalamic slices were dissected and placed in oxygenated Minimum Essential Media (MEM)-α at 4°C; within 2 h, slices were singly perifused at 37°C with oxygenated MEM-α (0.15 ml/min), with or without oestradiol (24 pg/ml). After 4 h equilibration, fractions were collected for 4 h interposed with a 10 min exposure to specific GABAA or B receptor ligands (0.1–10 mm). The GABAA or B agonists (muscimol or baclofen) did not greatly influence GnRH release. However, GnRH increased (p < 0.05) after exposure to 10 mm GABAA or B antagonists (bicuculline or CGP52432, respectively). The GABAA antagonist stimulated greater sustained GnRH release (p < 0.05) in the absence of oestradiol than in its presence. The bioactivity of the released GnRH was studied using a hypothalamus-pituitary sequential double-chamber perifusion. Only after exposure of hypothalamic slices to the GABAA antagonist, did the hypothalamic eluate stimulate luteinizing hormone release from pituitary fragments (p < 0.05) confirming that the GABAA antagonist stimulated release of biologically active GnRH. In summary, GnRH release from the hypothalamus is predominantly under GABAA receptor inhibitory control and this is attenuated in the presence of oestradiol. [ABSTRACT FROM AUTHOR]

SUMMARY The 1998 Australian Radiologist Workforce Survey findings form the basis of the present report, prepared by the Workforce Committee of the Royal Australian and New Zealand College of Radiologists (RANZCR). A more detailed report can be accessed through the RANZCR web site (http://www.ranzcr.edu.au). This follows similar previously published reports by the Workforce Committee in the 1990s. The issues of radiologist workforce supply and demand are examined, and benchmarks again reviewed. One of the conclusions of the present report is a possible upcoming shortage of radiologists in Australia, due to several factors, including a possible increase in the attrition rate of an ageing radiologist population, increasing female participation in the workforce, and increasing medical imaging utilization rates. In comparison with other Organization for Economic Cooperation and Development (OECD) nations, Australia had a mid-range supply of radiologists, and also medical imaging utilization, although there has been an increase in the latter. Australian radiologist annual workloads appear to be increasing. [ABSTRACT FROM AUTHOR]

Flying birds and bats have simplified gastrointestinal tracts (GITs) and low intestinal mass to facilitate flight. Previous work showed reduced GIT transit times in birds relative to other vertebrates-but GIT transit has never been collectively quantified for bats. Unique among mammals, bat GIT microbiomes are dominated by Pseudomonadota bacteria (previously Proteobacteria), which also dominate the microbiomes of flying birds - we hypothesized this convergence to result from rapid GIT transit times for both volant taxa. We conducted a meta-analysis of vertebrate GIT transit times which showed that bats and flying birds have significantly faster transit times relative to nonvolant vertebrates. Additionally, within the bat order (Chiroptera), we demonstrated decreasing transit times associated with increasing body mass, a pattern contrasting other vertebrates (including volant birds) and possibly influencing GIT microbiome composition. This inverted mass-transit association is likely driven by diet as fruit- and nectar-consuming Pteropodids are the largest of all bats.

Religion has had a mixed impact on society, with some followers engaging in violent behavior. It remains unclear why some followers perpetrate violence and others are peaceful. We argue that religious overclaiming is one facet of religion to be considered when trying to understand the relationship between religion and violence. Across two studies ( N  = 551), we tested the hypothesis that a higher tendency to overclaim knowledge of the Christian Bible would be associated with higher perpetration of intimate partner violence (IPV). We also tested the hypotheses that men who overclaim would be most likely to engage in the perpetration of IPV, and that higher religiosity would attenuate the effects of religious overclaiming. In both studies, participants completed a measure of religious overclaiming, reported on their perpetration of IPV, and reported their religiosity. Our findings across both studies indicated that Bible overclaiming was associated with greater perpetration of IPV. Further, Study 1 found that those high in Bible overclaiming (especially men) engaged in the most perpetration of IPV. However, this gender-based finding did not replicate in Study 2. Both studies found that religiosity was unassociated with the perpetration of IPV. Our results provide evidence that Bible overclaiming is related to the perpetration of IPV. Specifically, individuals who claim to know religious concepts that do not exist are associated with a higher risk for IPV., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interests with respect to the authorship and/or publication of this article.

Activation of the extracellular signal-regulated kinase-2 (ERK2) by phosphorylation has been shown to involve changes in protein dynamics, as determined by hydrogen-deuterium exchange mass spectrometry (HDX-MS) and NMR relaxation dispersion measurements. These can be described by a global exchange between two conformational states of the active kinase, named 'L' and 'R,' where R is associated with a catalytically productive ATP-binding mode. An ATP-competitive ERK1/2 inhibitor, Vertex-11e, has properties of conformation selection for the R-state, revealing movements of the activation loop that are allosterically coupled to the kinase active site. However, the features of inhibitors important for R-state selection are unknown. Here, we survey a panel of ATP-competitive ERK inhibitors using HDX-MS and NMR and identify 14 new molecules with properties of R-state selection. They reveal effects propagated to distal regions in the P +1 and helix αF segments surrounding the activation loop, as well as helix αL16. Crystal structures of inhibitor complexes with ERK2 reveal systematic shifts in the Gly loop and helix αC, mediated by a Tyr-Tyr ring stacking interaction and the conserved Lys-Glu salt bridge. The findings suggest a model for the R-state involving small movements in the N-lobe that promote compactness within the kinase active site and alter mobility surrounding the activation loop. Such properties of conformation selection might be exploited to modulate the protein docking interface used by ERK substrates and effectors., Competing Interests: JA, DV, DJ, LP, NA No competing interests declared, GV Guy Vigers is Structural Biology Consultant at Allium Consulting LLC, HC Dr. Huifen Chen is Distinguished Scientist at Genentech, Inc, JM Dr. John Moffat is Distinguished Scientist at Genentech, Inc, (© 2023, Anderson et al.)

Over the past two decades, research on bat-associated microbes such as viruses, bacteria and fungi has dramatically increased. Here, we synthesize themes from a conference symposium focused on advances in the research of bats and their microbes, including physiological, immunological, ecological and epidemiological research that has improved our understanding of bat infection dynamics at multiple biological scales. We first present metrics for measuring individual bat responses to infection and challenges associated with using these metrics. We next discuss infection dynamics within bat populations of the same species, before introducing complexities that arise in multi-species communities of bats, humans and/or livestock. Finally, we outline critical gaps and opportunities for future interdisciplinary work on topics involving bats and their microbes.

Environmental DNA (eDNA) sampling provides sensitive early detection capabilities for recently introduced taxa. However, natural resource managers struggle with how to integrate eDNA results into an early detection rapid response program because positive eDNA detections are not always indicative of an eventual infestation. We used a structured decision making (SDM) framework to evaluate appropriate response actions to hypothetical eDNA early detections of an introduced aquatic plant in Sebago Lake (Maine, USA). The results were juxtaposed to a recent study that used a similar SDM approach to evaluate response actions to hypothetical eDNA early detections of introduced mussels in Jordanelle Reservoir (Utah, USA). We found that eDNA early detections were not actionable in Sebago Lake because the plant's invasion potential was spatially constrained and the current management activities provided acceptable levels of mitigation. In Jordanelle Reservoir, eDNA detections were actionable due to high invasion potential and analyses supported management actions to contain the invasion. The divergent outcomes of the two case studies are related to the unique attributes of the habitats and species, highlighting the utility of the SDM approach when considering an eDNA monitoring program. We use these two case studies to present a general SDM framework and a set of heuristics that can be efficiently applied to eDNA early detection rapid response scenarios and other instances associated with indeterminant eDNA detections, especially when there is an imperative to make decisions as quickly as possible., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

The nucleus accumbens (NAc) is central to motivation and action, exhibiting one of the highest densities of neuropeptide Y (NPY) in the brain. Within the NAc, NPY plays a role in reward and is involved in emotional behavior and in increasing alcohol and drug addiction and fat intake. Here, we examined NPY innervation and neurons of the NAc in humans and other anthropoid primates in order to determine whether there are differences among these various species that would correspond to behavioral or life history variables. We quantified NPY-immunoreactive axons and neurons in the NAc of 13 primate species, including humans, great apes, and monkeys. Our data show that the human brain is unique among primates in having denser NPY innervation within the NAc, as measured by axon length density to neuron density, even after accounting for brain size. Combined with our previous finding of increased dopaminergic innervation in the same region, our results suggest that the neurochemical profile of the human NAc appears to have rendered our species uniquely susceptible to neurophysiological conditions such as addiction. The increase in NPY specific to the NAc may represent an adaptation that favors fat intake and contributes to an increased vulnerability to eating disorders, obesity, as well as alcohol and drug dependence. Along with our findings for dopamine, these deeply rooted structural attributes of the human brain are likely to have emerged early in the human clade, laying the groundwork for later brain expansion and the development of cognitive and behavioral specializations.