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Abstract Oncogenic KRAS mutations are well-described functionally and are known to drive tumorigenesis. Recent reports describe a significant prevalence of KRAS allelic imbalances or gene dosage changes in human cancers, including loss of the wild-type allele in KRAS mutant cancers. However, the role of wild-type KRAS in tumorigenesis and therapeutic response remains elusive. We report an in vivo murine model of colorectal cancer featuring deletion of wild-type Kras in the context of oncogenic Kras. Deletion of wild-type Kras exacerbates oncogenic KRAS signalling through MAPK and thus drives tumour initiation. Absence of wild-type Kras potentiates the oncogenic effect of KRASG12D, while incidentally inducing sensitivity to inhibition of MEK1/2. Importantly, loss of the wild-type allele in aggressive models of KRASG12D-driven CRC significantly alters tumour progression, and suppresses metastasis through modulation of the immune microenvironment. This study highlights the critical role for wild-type Kras upon tumour initiation, progression and therapeutic response in Kras mutant CRC.

Introduction Pediatric behavioral and mental health (BMH) disorders are increasingly common, but most pediatricians feel inadequately trained to manage them. We implemented a case-based, longitudinal curriculum in BMH within a pediatric residency program to prepare trainees to diagnose and manage these conditions. Methods The pediatric residency program at Wright State University/Wright-Patterson Medical Center implemented a new BMH curriculum in 2020–2021. The curriculum consisted of five simulated cases involving depression, anxiety, attention deficit disorder with hyperactivity (ADHD), developmental delays, behavioral concerns, and autism. To reflect follow-up within a continuity clinic, cases included initial encounters and multiple follow-up visits. Faculty facilitators led residents in monthly small-group meetings over the academic year, with each session consisting of two to three simulated patient encounters. Residents completed pre-post surveys regarding their confidence in diagnosing and managing BMH conditions and pre- and posttests to evaluate the impact of the curriculum on knowledge gains. Results All 47 pediatric residents participated in the curriculum; 38 (81%) completed pre-post surveys. Upon completion of the curriculum, residents reported significantly increased confidence in managing ADHD, treating depression, creating safety plans for suicidality, recognizing autism, and counseling patients and families on special education services. Knowledge-based pre- and posttests completed by 25 residents (53%) also demonstrated significant improvement (M = 92.4, SD = 10.9, pre vs. M = 99.3, SD = 6.6, post, p = .009). Discussion This case-based, longitudinal curriculum in pediatric BMH simulating patient continuity improved residents’ confidence and knowledge in diagnosing and managing common BMH conditions.

Abstract The biological larvicide Bacillus thuringiensis var. israelensis (Bti) is used worldwide to control reproduction of mosquitoes in freshwater habitats. However, its impact on the ecosystem including nontarget species is often unclear. In addition, it is unknown how Bti larvicide may interact with local mosquito predators to shape oviposition site selection of mosquitoes. We used an outdoor mesocosm experiment to investigate the effects of realistic concentrations of the bio‐larvicide Bti on Culex oviposition, larval density, survivorship, and on densities of nontarget species. We also manipulated the complexity of the community by manipulating the presence of dragonfly larvae as a predator. Culex oviposition was unaffected by Bti but the larvicide effectively reduced larval density and survivorship in all treatments. Bti did not affect nontarget insects but stimulated phytoplankton density at the expense of lower herbivore density. The presence of dragonfly larvae in mesocosms did not reduce Culex oviposition or larval sensitivity to Bti. We conclude that Bti may effectively reduce the density and survivorship of Culex quinquefasciatus mosquitoes in this part of East Africa, but possibly at the cost of higher phytoplankton densities. Bti‐treated mesocosms were not more or less attractive for mosquitoes, suggesting that its application would not alter their oviposition behavior in the field.

It remains critical to identify colorectal cancers (CRC) that will disseminate as early as possible. Here, the authors identify CRC tumours that are aggressive and prone to early dissemination, characterised by epithelial TGFβ and growth-factor signalling - which could be targeted with MEK/EGFR inhibitors.

Abstract The progressive image scrambling procedure is an effective way of determining sensitivity to image features at different stages of the visual system, but it hasn’t yet been used to evaluate neuronal responses in birds. We determined the effect of progressively scrambling images of objects on the population responses of anterior entopallium (ENTO), mesopallium ventrolaterale (MVL), and posterior nidopallium intermediate pars lateralis (NIL) in pigeons. We found that MVL responses were more sensitive to both the intact objects and the highly scrambled images, whereas ENTO showed no clear preference for the different stimuli. In contrast, the NIL population response strongly preferred the original images over the scrambled images. These findings suggest that the anterior tectofugal pathway may process local shape in a hierarchical manner, and the posterior tectofugal pathway may process global shape of greater complexity. Another possibility is that the differential responses between ENTO/MVL and NIL may reflect an anterior–posterior map of varying sensitivity to spatial frequency.

We introduce a method, topological acoustic sensing, which exploits changes in the geometric phase of nonseparable coherent superpositions of acoustic waves to sense mass defects in arrays of coupled acoustic waveguides. Theoretical models and experimental results shed light on the origin of the behavior and sensitivity of the geometric phase due to the presence of mass defects. The choice of the coherent superposition of waves used to probe the defects as well as the mathematical representation determining the topological characteristics of its space of states are shown to be critical in maximizing the sensitivity of the topological acoustic sensing method.

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Abstract Discriminating between object categories (e.g., conspecifics, food, potential predators) is a critical function of the primate and bird visual systems. We examined whether a similar hierarchical organization in the ventral stream that operates for processing faces in monkeys also exists in the avian visual system. We performed electrophysiological recordings from the pigeon Wulst of the thalamofugal pathway, in addition to the entopallium (ENTO) and mesopallium ventrolaterale (MVL) of the tectofugal pathway, while pigeons viewed images of faces, scrambled controls, and sine gratings. A greater proportion of MVL neurons fired to the stimuli, and linear discriminant analysis revealed that the population response of MVL neurons distinguished between the stimuli with greater capacity than ENTO and Wulst neurons. While MVL neurons displayed the greatest response selectivity, in contrast to the primate system no neurons were strongly face-selective and some responded best to the scrambled images. These findings suggest that MVL is primarily involved in processing the local features of images, much like the early visual cortex.

Plain English summary The COPD Patient-Powered Research Network (PPRN) asked adults with COPD and their caregivers to suggest areas for future research on COPD. Researchers analyzed 7336 survey responses and created six research areas to reflect their suggestions: (1) family/social/community research, (2) well-being, (3) research on a cure for COPD, (4) new drugs and treatments, (5) policy concerns, and (6) natural therapies. Several research topics patients and their caregivers identified as important have received little attention from researchers in the past and could be valuable topics for researchers to explore.

Background: Anti-neutrophil cytoplasm antibody-associated vasculitis is a multisystem, autoimmune disease that causes organ failure and death. Physical removal of pathogenic autoantibodies by plasma exchange is recommended for severe presentations, along with high-dose glucocorticoids, but glucocorticoid toxicity contributes to morbidity and mortality. The lack of a robust evidence base to guide the use of plasma exchange and glucocorticoid dosing contributes to variation in practice and suboptimal outcomes. Objectives: We aimed to determine the clinical efficacy of plasma exchange in addition to immunosuppressive therapy and glucocorticoids with respect to death and end-stage renal disease in patients with severe anti-neutrophil cytoplasm antibody-associated vasculitis. We also aimed to determine whether or not a reduced-dose glucocorticoid regimen was non-inferior to a standard-dose regimen with respect to death and end-stage renal disease. Design: This was an international, multicentre, open-label, randomised controlled trial. Patients were randomised in a two-by-two factorial design to receive either adjunctive plasma exchange or no plasma exchange, and either a reduced or a standard glucocorticoid dosing regimen. All patients received immunosuppressive induction therapy with cyclophosphamide or rituximab. Setting: Ninety-five hospitals in Europe, North America, Australia/New Zealand and Japan participated. Participants: Participants were aged ≥ 16 years with a diagnosis of granulomatosis with polyangiitis or microscopic polyangiitis, and either proteinase 3 anti-neutrophil cytoplasm antibody or myeloperoxidase anti-neutrophil cytoplasm antibody positivity, and a glomerular filtration rate of

Right-sided colorectal cancer (rCRC) has a different mutational spectrum to the left-sided counterpart. Here the authors develop a mouse model of rCRC that recapitulates human BRAF-mutant rCRC and show that loss of TGFβ-receptor signalling and inflammation induce the development of colonic tumours with a foetal-like phenotype.

Non-human animals tend to solve behavioral tasks using local information. Pigeons are particularly biased toward using the local features of stimuli to guide behavior in small-scale environments. When behavioral tasks are performed in large-scale environments, pigeons are much better global processors of information. The local and global strategies are mediated by two different fovea in the pigeon retina that are associated with the tectofugal and thalamofugal pathways. We discuss the neural mechanisms of pigeons’ bias for local information within the tectofugal pathway, which terminates at an intermediate stage of extracting shape complexity. We also review the evidence suggesting that the thalamofugal pathway participates in global processing in pigeons and is primarily engaged in constructing a spatial representation of the environment in conjunction with the hippocampus.

MDM2 and BET inhibitors have shown efficacy in AML treatment. Here, the authors show that the two compounds can synergize through both p53 protein stabilization and inhibition of BRD4-mediated repression of p53 target genes.

Purpose: Gender disparities within academic promotion have been reported in several medical specialties. Female representationin association with research productivity has not been reported among academic dermatologists. As research productivity is a heavily weighted factor in determining promotion, we sought to determine whether gender disparities in academic rank and scholarly impact, measured by the h-index, exist in academic dermatology.Methods: In 2015, the authors determined gender and academic rank using academic dermatology department websites. H- index and publication range were determined using the Scopus database. Rank, h-index, and publication range were compared between male and female academic dermatologists.Results: The h-index of academic dermatologists increased with successive academic rank from Assistant Professor through Professor (p

Mice are a widely used pre-clinical model system in large part due to their potential for genetic manipulation. The ability to manipulate gene expression in specific cells under temporal control is a powerful experimental tool. The liver is central to metabolic homeostasis and a site of many diseases, making the targeting of hepatocytes attractive. Adeno-associated virus 8 (AAV8) vectors are valuable instruments for the manipulation of hepatocellular gene expression. However, their off-target effects in mice have not been thoroughly explored. Here, we sought to identify the short-term off-target effects of AAV8 administration in mice. To do this, we injected C57BL/6J wild-type mice with either recombinant AAV8 vectors expressing Cre recombinase or control AAV8 vectors and characterised the changes in general health and in liver physiology, histology and transcriptomics compared to uninjected controls. We observed an acute and transient trend for reduction in homeostatic liver proliferation together with induction of the DNA damage marker γH2AX following AAV8 administration. The latter was enhanced upon Cre recombinase expression by the vector. Furthermore, we observed transcriptional changes in genes involved in circadian rhythm and response to infection. Notably, there were no additional transcriptomic changes upon expression of Cre recombinase by the AAV8 vector. Overall, there was no evidence of liver injury, and only mild T-cell infiltration was observed 14 days following AAV8 infection. These data advance the technique of hepatocellular genome editing through Cre-Lox recombination using Cre expressing AAV vectors, demonstrating their minimal effects on murine physiology and highlight the more subtle off target effects of these systems.

A 52-year-old female presented with an asymptomatic cyst-like lesion on her right labia majora present for several years. Excision revealed a 3-mm cystic lesion containing complex networks of thin fronds of clear apocrine cells and basaloid cells, features characteristic of hidradenoma papilliferum (HP). In contrast to the medical literature, the lesion was connected to the overlying epithelium by a straight duct, a feature characteristic of apocrine glands. Searching of six different dermatopathology study sets revealed 11 cases diagnosed as HP. Histological review of the eight available cases for review revealed none that were diagnosed correctly. Six were syringocystadenoma papilliferum and two were trichoepithelioma. HP is a fascinating lesion that needs further study and requires better diagnostic criteria.

Whether the Wnt enhanceosome’ components BCL9/9l can affect intestinal homeostasis and tumorigenesis is still unclear. Using conditional Bcl9/9l KO mice, the authors of this study show that the BCL9/9l complex is required for intestinal stem cells to drive tissue regeneration and that loss of BCL9/9l suppresses Wnt-driven transformation.

Environmental footprinting, underpinned by systematic life-cycle thinking, is increasingly seen as a critical concept for designing policies to fight climate change. The holistic nature of a life-cycle approach, built using the principles of Life Cycle Assessment (LCA), enables policy makers to understand the potential impacts and benefits of policy options. Although LCA is a widely used and well-established method, methodological aspects such as the quality of background data, model uncertainty, and comparison against existing literature are not usually communicated effectively to wider audiences, in particular policy makers. This paper introduces a novel hybrid data quality assessment method in the context of a case study based on the Scottish Waste Environmental Footprint Tool, a newly developed environmental life-cycle thinking tool. It offers an accessible method to present results of the data quality assessment of environmental models to policy makers and helps identify areas of improvements in future upgrades.

Surfactant proteins A (SP-A) and D (SP-D) are soluble innate immune molecules which maintain lung homeostasis through their dual roles as anti-infectious and immunomodulatory agents. SP-A and SP-D bind numerous viruses including influenza A virus, respiratory syncytial virus (RSV) and human immunodeficiency virus (HIV), enhancing their clearance from mucosal points of entry and modulating the inflammatory response. They also have diverse roles in mediating innate and adaptive cell functions and in clearing apoptotic cells, allergens and other noxious particles. Here, we review how the properties of these first line defense molecules modulate inflammatory responses, as well as host-mediated immunopathology in response to viral infections. Since SP-A and SP-D are known to offer protection from viral and other infections, if their levels are decreased in some disease states as they are in severe asthma and chronic obstructive pulmonary disease (COPD), this may confer an increased risk of viral infection and exacerbations of disease. Recombinant molecules of SP-A and SP-D could be useful in both blocking respiratory viral infection while also modulating the immune system to prevent excessive inflammatory responses seen in, for example, RSV or coronavirus disease 2019 (COVID-19). Recombinant SP-A and SP-D could have therapeutic potential in neutralizing both current and future strains of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus as well as modulating the inflammation-mediated pathology associated with COVID-19. A recombinant fragment of human (rfh)SP-D has recently been shown to neutralize SARS-CoV-2. Further work investigating the potential therapeutic role of SP-A and SP-D in COVID-19 and other infectious and inflammatory diseases is indicated.