Preparation of High-quality Hematoxylin and Eosin–stained Sections from Rodent Mammary Gland Whole Mounts for Histopathologic Review

Identifying environmental exposures that cause adverse mammary gland outcomes in rodents is a first step in disease prevention in humans and domestic pets. ‘Whole mounts’ are an easy and inexpensive tissue preparation method that can elucidate typical or abnormal mammary gland morphology in rodent studies. Here we propose procedures to facilitate the use of whole mounts for histological identification of grossly noted tissue alterations. We noted lesions in mammary whole mounts from 14 month old CD-1 mice that were not found in the contralateral gland hematoxylin and eosin (H&E)-stained section. Whole mounts were removed from the slide and carefully processed to produce high quality histological sections that mirrored the quality of the original H&E-stained section in order to properly diagnose the unidentified gross abnormalities. Incorporation of this method into testing protocols which focus on low-dose human relevant chemicals and endocrine disruptors will increase the chances of identifying lesions in the gland and reduce the risk of false negative findings. This method can be especially invaluable when lesions are not always palpable during the course of the study or visible at necropsy, or when a single cross-section of the mammary gland is otherwise used for detecting lesions

Gender Issues Among Academic AMS Members: Comparisons with the 1993 Membership Survey

This is the publisher's version. It can also be found here: http://dx.doi.org/10.1175/2009BAMS2538.

A silver lining: Revitalising impacts of Covid for students, staff, and the institution in Higher Education - a case study

In the past decade, global higher education has undergone significant transformations in learning and teaching (L&T) practices. The 2020 Covid-19 pandemic and subsequent lockdowns acted as a disruptive force, prompting rapid changes in L&T methods—dubbed ‘panic-gogy.’ We examine a UK University’s response to the pandemic’s impact on L&T, focusing on institutional, staff, and student dimensions. The university strategically prioritised teaching and student experiences, implemented staff development initiatives, and addressed challenges in student engagement and placements post-pandemic. We identify aspects that led to successful long-term adoption of approaches to revitalise provision and highlight long-term challenges that still need solutions

Violence Prevention: Reaching Adolescents with the Message

To identify an effective medium for communicating with adolescents in a large-scale, cost-effective violence prevention program. A set of youth violence prevention programs was established at The Stamford Hospital, a level II trauma center. The traveling version of the program was presented to middle school students in four parts: 1) a rap music video created by our violence prevention staff, 2) a facilitated discussion about dealing with anger, 3) a video of a trauma resuscitation in our emergency department, and 4) a commercial video of a teenage boy paralyzed after a gunshot wound. A written questionnaire with a five-point rating scale (1 to 5) was used to survey the audience 1 month after the program. The survey assessed the respondents\u27 recall of each part of the program and the perceptions of the value of each part in identifying the problem of violence and reducing violent behavior. Results: Of 99 respondents, the highest ratings for retention, problem identification, and impact were given to the commercial video (combined average category ranking of 11.394) and the rap music video (11.182). The trauma resuscitation video and the discussion of anger were ranked as being less effective (10.253 and 9.383, respectively). The audience seemed to comprehend the main point of the program and ranked the program, as a whole, higher than any of the parts when measured by success at problem identification and impact. Effective communication with adolescents is possible through many avenues. Children of the video age respond well to visual material. A violence prevention program should incorporate effective multimedia presentations. A variety of methods hi combination proves to be most effective

The thrombopoietin receptor : revisiting the master regulator of platelet production

Thrombopoietin (TPO) and its receptor, MPL, are the primary regulators of platelet production and critical for hematopoietic stem cell (HSC) maintenance. Since TPO was first cloned in 1994, the physiological and pathological roles of TPO and MPL have been well characterized, culminating in the first MPL agonists being approved for the treatment of chronic immune thrombocytopenia in 2008. Dysregulation of the TPO-MPL signaling axis contributes to the pathogenesis of hematological disorders: decreased expression or function results in severe thrombocytopenia progressing to bone marrow failure, while hyperactivation of MPL signaling, either by mutations in the receptor or associated Janus kinase 2 (JAK2), results in pathological myeloproliferation. Despite its importance, it was only recently that the long-running debate over the mechanism by which TPO binding activates MPL has been resolved. This review will cover key aspects of TPO and MPL structure and function and their importance in receptor activation, discuss how these are altered in hematological disorders and consider how a greater understanding could lead to the development of better-targeted and more efficacious therapies

Paradoxical activation of the protein kinase-transcription factor ERK5 by ERK5 kinase inhibitors.

The dual protein kinase-transcription factor, ERK5, is an emerging drug target in cancer and inflammation, and small-molecule ERK5 kinase inhibitors have been developed. However, selective ERK5 kinase inhibitors fail to recapitulate ERK5 genetic ablation phenotypes, suggesting kinase-independent functions for ERK5. Here we show that ERK5 kinase inhibitors cause paradoxical activation of ERK5 transcriptional activity mediated through its unique C-terminal transcriptional activation domain (TAD). Using the ERK5 kinase inhibitor, Compound 26 (ERK5-IN-1), as a paradigm, we have developed kinase-active, drug-resistant mutants of ERK5. With these mutants, we show that induction of ERK5 transcriptional activity requires direct binding of the inhibitor to the kinase domain. This in turn promotes conformational changes in the kinase domain that result in nuclear translocation of ERK5 and stimulation of gene transcription. This shows that both the ERK5 kinase and TAD must be considered when assessing the role of ERK5 and the effectiveness of anti-ERK5 therapeutics

Phase Separation in Lean-Grade Duplex Stainless Steel 2101

The use of duplex stainless steels (DSS) in nuclear power generation systems is limited by thermal instability that leads to embrittlement in the temperature range of 204°C to 538°C. New lean-grade alloys, such as 2101, offer the potential to mitigate these effects. Thermal embrittlement was quantified through impact toughness and hardness testing on samples of alloy 2101 after aging at 427°C for various durations (1–10,000 h). Additionally, atom probe tomography (APT) was utilized in order to observe the kinetics of α–α′ separation and G-phase formation. Mechanical testing and APT data for two other DSS alloys, 2003 and 2205, were used as a reference to 2101. The results show that alloy 2101 exhibits superior performance compared to the standard-grade DSS alloy 2205 but inferior to the lean-grade alloy 2003 in mechanical testing. APT data demonstrate that the degree of α–α′ separation found in alloy 2101 closely resembles that of 2205 and greatly exceeds 2003. Additionally, contrary to what was observed in 2003, 2101 demonstrated G-phase like precipitates after long aging times, although precipitates were not as abundant as was observed in 2205

The effects of exogenous fibrolytic enzymes on the in vitro release of xylooligosaccharides and monosaccharides varies across six varieties of wheat

Wheat is a widely used cereal grain for pig and poultry feeds globally. Despite this, there are noticeable differences in its nutritive value, potentially due to varying characteristics like inherent non-starch polysaccharide (NSP) content and composition. Fibrolytic enzymes help degrade NSP and thereby improve feed efficiency in livestock. However, it has been suggested that these enzymes have different effects dependent upon the characteristics of the wheat variety used in a feed. This study investigated the efficacy of different enzyme-wheat variety combinations, by quantifying the release of NSP-derived xylooligosaccharides (XOS) and monosaccharides from six varieties of wheat (Maris Huntsman, Highbury, Paragon, Sinuelo, Chinese Spring and Pavon 76) over a 24 hour in vitro incubation with commercially available fibrolytic enzymes (Econase XT, Econase MP1000 or Barley P700). Complete non-starch acid hydrolysis showed there were differences between varieties in their total monosaccharide contents (P<0.001). There were significant wheat variety x enzyme x incubation time interactions for the release of xylobiose, galactose and glucose (all P<0.001) and significant enzyme x wheat variety interactions for the release of xylotriose (P=0.022), xylose (P<0.001) and arabinose (P=0.028). Clear differences in release of XOS were observed between the different combinations of enzyme and wheat variety. Econase XT increased xylotriose release from Highbury wheat, and xylobiose release from Sinuelo, with both wheat varieties showing comparable release of xylose. These findings suggest that the fibrolytic enzymes tested have some specificity for the wheat varieties. Hence it might be possible to optimise the combinations of wheat variety and enzyme used in animal feeds, to help maximise the feed efficiency of livestock

Structure of the thrombopoietin-MPL receptor complex is a blueprint for biasing hematopoiesis

Thrombopoietin (THPO or TPO) is an essential cytokine for hematopoietic stem cell (HSC) maintenance and megakaryocyte differentiation. Here, we report the 3.4 Å resolution cryoelectron microscopy structure of the extracellular TPO-TPO receptor (TpoR or MPL) signaling complex, revealing the basis for homodimeric MPL activation and providing a structural rationalization for genetic loss-of-function thrombocytopenia mutations. The structure guided the engineering of TPO variants (TPOmod) with a spectrum of signaling activities, from neutral antagonists to partial- and super-agonists. Partial agonist TPOmod decoupled JAK/STAT from ERK/AKT/CREB activation, driving a bias for megakaryopoiesis and platelet production without causing significant HSC expansion in mice and showing superior maintenance of human HSCs in vitro. These data demonstrate the functional uncoupling of the two primary roles of TPO, highlighting the potential utility of TPOmod in hematology research and clinical HSC transplantation