Great Hospitals: The History of Neurosurgery at the University of Vermont Medical Center-A Macroscopic Examination of Microscope-Savvy Pioneers.

The University of Vermont's (UVM) Division of Neurosurgery is enshrined in a rich history of innovation and academic prowess, which have significantly contributed to making neurosurgery the field it is today. From humble beginnings, the department was started by one Raymond Madiford Peardon "Pete" Donaghy on a parenthetically watertight research budget amounting to $25 and shared space in a Quonset hut. Passion and commitment to progress, as well as an innate openness to collaboration, propelled Pete Donaghy, his colleagues, pupils, and successors to establish an exemplary center for treatment of neurosurgical disease, with multiple revolutionary accomplishments along the way. These accomplishments include the birth and promotion of microneurosurgery, the performance of the first extracranial to intracranial bypass, and the education of other neurosurgical giants. The New England Skull Base Course, held annually in UVM's "R.M. Peardon Donaghy Microvascular and Skull Base Laboratory," is a 3-day cadaver-based teaching course for neurosurgery and ear nose and throat residents throughout New England. The course bears testament to Donaghy's everlasting influence on the UVM Division of Neurosurgery and continues to positively affect the education of countless trainees. The purpose of this historical perspective is to outline the events and accomplishments that define the UVM Division of Neurosurgery's many contributions to the field at large and the ongoing efforts to honor Donaghy's example through maintaining a culture of humility, hard work, and commitment to neurosurgical innovation and education.

An exploration of how the disruption of mainstream schooling during the COVID-19 crisis provided opportunities that we can learn from so that we may improve our future relationship with the more-than-human world.

The COVID-19 crisis forced educators globally to reassess delivery of their curricula and educational priorities. Already the worsening climate crisis amid human beings' deleterious relationship with the more-than-human world has caused many educators to demand radical reconsiderations as to the purpose and meaning of education. We ask: how did the disruption of mainstream schooling, during the COVID-19 crisis, provide opportunities that we can learn from so that we may improve our future relationship with the more-than-human world? We examine research that shows children can benefit from outdoor, contemplative pedagogical approaches that differ from their usual indoor classroom experience. Outdoor, contemplative pedagogical approaches involving freedom from "clock-time", as were experienced by some children during the lockdowns, can allow for ways of knowing and states of being that are often marginalised or excluded from mainstream schools in industrial growth societies. We draw on underpinning theory that argues the status quo in schools conforms to a factory model of schooling that prioritises limited ways of knowing and states of being, thus, lacking the perspectives needed to enable children to cultivate a sustained, healthy relationship with nature. We suggest that outdoor contemplative approaches are required that allow children to dwell pedagogically and experience their relationship with the more-than-human world.

Degradation of GSPT1 causes TP53-independent cell death in leukemia while sparing normal hematopoietic stem cells.

Targeted protein degradation is a rapidly advancing and expanding therapeutic approach. Drugs that degrade GSPT1 via the CRL4CRBN ubiquitin ligase are a new class of cancer therapy in active clinical development with evidence of activity against acute myeloid leukemia in early-phase trials. However, other than activation of the integrated stress response, the downstream effects of GSPT1 degradation leading to cell death are largely undefined, and no murine models are available to study these agents. We identified the domains of GSPT1 essential for cell survival and show that GSPT1 degradation leads to impaired translation termination, activation of the integrated stress response pathway, and TP53-independent cell death. CRISPR/Cas9 screens implicated decreased translation initiation as protective following GSPT1 degradation, suggesting that cells with higher levels of translation are more susceptible to the effects of GSPT1 degradation. We defined 2 Crbn amino acids that prevent Gspt1 degradation in mice, generated a knockin mouse with alteration of these residues, and demonstrated the efficacy of GSPT1-degrading drugs in vivo with relative sparing of numbers and function of long-term hematopoietic stem cells. Our results provide a mechanistic basis for the use of GSPT1 degraders for the treatment of cancer, including TP53-mutant acute myeloid leukemia.

Pulmonary endothelial cells from different vascular segments exhibit unique recovery from acidification and Na+/H+ exchanger isoform expression.

Sodium-hydrogen exchangers (NHEs) tightly regulate intracellular pH (pHi), proliferation, migration and cell volume. Heterogeneity exists between pulmonary endothelial cells derived from different vascular segments, yet the activity and isoform expression of NHEs between these vascular segments has not been fully examined. Utilizing the ammonium-prepulse and recovery from acidification technique in a buffer lacking bicarbonate, pulmonary microvascular and pulmonary artery endothelial cells exhibited unique recovery rates from the acid load dependent upon the concentration of the sodium transport inhibitor, amiloride; further, pulmonary artery endothelial cells required a higher dose of amiloride to inhibit sodium-dependent acid recovery compared to pulmonary microvascular endothelial cells, suggesting a unique complement of NHEs between the different endothelial cell types. While NHE1 has been described in pulmonary endothelial cells, all NHE isoforms have not been accounted for. To address NHE expression in endothelial cells, qPCR was performed. Using a two-gene normalization approach, Sdha and Ywhag were identified for qPCR normalization and analysis of NHE isoforms between pulmonary microvascular and pulmonary artery endothelial cells. NHE1 and NHE8 mRNA were equally expressed between the two cell types, but NHE5 expression was significantly higher in pulmonary microvascular versus pulmonary artery endothelial cells, which was confirmed at the protein level. Thus, pulmonary microvascular and pulmonary artery endothelial cells exhibit unique NHE isoform expression and have a unique response to acid load revealed through recovery from cellular acidification.

Enhancing Nature Connection and Positive Affect in Children through Mindful Engagement with Natural Environments.

Nature connection, which describes a positive relationship between humans and the rest of nature, has been recognised as a worthwhile goal of all education. Given its association with wellbeing, as well as the fact that it can predict ecological behaviours in children, there have been several calls for it to become central to environmental education, and an important tool in tackling climate change. Previous research has reported the success of short-term interventions in increasing nature connection in children, but to date no empirical studies have looked at how mindful engagement with nature can promote both nature connection and positive affect. This study took place in a nature reserve in Wales and included n = 74 children, aged 9-10, who took part in three mindful activities. Pre- and post- measures included nature connection and positive/negative affect. Analysis showed a significant small to medium effect of the activity on nature connection. Moreover, positive affect significantly increased post-activity, while negative affect showed a small decrease.

Child Abuse: The Consequence of an Undiagnosed Giant Olfactory Groove Meningioma?

Olfactory groove meningiomas are slow-growing tumors that manifest with headaches, changes in vision, and personality changes. The anatomic location of these tumors makes psychiatric disturbances more common early in the stage of tumors than focal neurological deficits. The case study here describes a unique instance of an undiagnosed giant olfactory groove meningioma in a young mother who was charged with a felony of aggravated child abuse for the death of her toddler daughter. The patient underwent gross tumor resection and radiation therapy, which halted the visual decline, resolved the frontal headaches, and the patient showed improved mood. In this patient, the insidious onset of personality changes without obvious focal neurologic deficits until late as well as a history of depression likely contributed to the delayed diagnosis. Failure to notice these initial behavioral manifestations in these patients allows for further psychiatric and cognitive decline, which can result in devastating social consequences.

Urothelial cell carcinoma presenting with rapid visual deterioration, a case of rare brain metastases with unique clinical presentation.

BACKGROUND: Urothelial cell carcinoma (UCC), the most common cancer of the urinary system, rarely metastasizes to the brain. 1-3 More rare still is the subset of patients with urothelial carcinoma brain metastases whose UCC primary is first diagnosed at the same time as their CNS metastatic disease, with oncologic workup prompted by CNS clinical manifestations.4 Paraneoplastic optic neuropathy (PON) is likewise a rare clinical entity, which has not yet been described in association with UCC brain metastases. CASE DESCRIPTION: Herein, we present the sentinel case of UCC believed to be of endometrial origin in an 81 year old woman initially presenting with symptoms of fatigue, nausea, vertigo, and rapidly deteriorating vision over the course of 1 month. Visual deterioration prompted neuro imaging remarkable for multiple supratentorial and infratentorial metastases as well as likely neoplastic inflammatory involvement of the bilateral optic nerves. The patient underwent a right temporal open brain biopsy, with pathology findings consistent with UCC. Subsequent PET scanning demonstrated a heavy burden of disease including an FDG-avid uterine mass with local and distal extension of disease including bilateral hydroureteronephrosis with obstruction of the distal ureters. The patient and her family elected to pursue home hospice without further workup or intervention. CONCLUSIONS: While this is the first such case presented, it is possible that UCC of the uterine wall represents a particularly aggressive form of the disease more prone to presenting with CNS metastases and PON.

Patterns of substrate affinity, competition, and degradation kinetics underlie biological activity of thalidomide analogs.

Pharmacologic agents that modulate ubiquitin ligase activity to induce protein degradation are a major new class of therapeutic agents, active in a number of hematologic malignancies. However, we currently have a limited understanding of the determinants of activity of these agents and how resistance develops. We developed and used a novel quantitative, targeted mass spectrometry (MS) assay to determine the relative activities, kinetics, and cell-type specificity of thalidomide and 4 analogs, all but 1 of which are in clinical use or clinical trials for hematologic malignancies. Thalidomide analogs bind the CRL4CRBN ubiquitin ligase and induce degradation of particular proteins, but each of the molecules studied has distinct patterns of substrate specificity that likely underlie the clinical activity and toxicities of each drug. Our results demonstrate that the activity of molecules that induce protein degradation depends on the strength of ligase-substrate interaction in the presence of drug, the levels of the ubiquitin ligase, and the expression level of competing substrates. These findings highlight a novel mechanism of resistance to this class of drugs mediated by competition between substrates for access to a limiting pool of the ubiquitin ligase. We demonstrate that increased expression of a nonessential substrate can lead to decreased degradation of other substrates that are critical for antineoplastic activity of the drug, resulting in drug resistance. These studies provide general rules that govern drug-dependent substrate degradation and key differences between thalidomide analog activity in vitro and in vivo.

Crbn I391V is sufficient to confer in vivo sensitivity to thalidomide and its derivatives in mice.

Thalidomide and its derivatives, lenalidomide and pomalidomide, are clinically effective treatments for multiple myeloma and myelodysplastic syndrome with del(5q). These molecules lack activity in murine models, limiting investigation of their therapeutic activity or toxicity in vivo. Here, we report the development of a mouse model that is sensitive to thalidomide derivatives because of a single amino acid change in the direct target of thalidomide derivatives, cereblon (Crbn). In human cells, thalidomide and its analogs bind CRBN and recruit protein targets to the CRL4CRBN E3 ubiquitin ligase, resulting in their ubiquitination and subsequent degradation by the proteasome. We show that mice with a single I391V amino acid change in Crbn exhibit thalidomide-induced degradation of drug targets previously identified in human cells, including Ikaros (Ikzf1), Aiolos (Ikzf3), Zfp91, and casein kinase 1a1 (Ck1α), both in vitro and in vivo. We use the Crbn I391V model to demonstrate that the in vivo therapeutic activity of lenalidomide in del(5q) myelodysplastic syndrome can be explained by heterozygous expression of Ck1α in del(5q) cells. We found that lenalidomide acts on hematopoietic stem cells with heterozygous expression of Ck1α and inactivation of Trp53 causes lenalidomide resistance. We further demonstrate that Crbn I391V is sufficient to confer thalidomide-induced fetal loss in mice, capturing a major toxicity of this class of drugs. Further study of the Crbn I391V model will provide valuable insights into the in vivo efficacy and toxicity of this class of drugs.

PPM1D-truncating mutations confer resistance to chemotherapy and sensitivity to PPM1D inhibition in hematopoietic cells.

Truncating mutations in the terminal exon of protein phosphatase Mg2+/Mn2+ 1D (PPM1D) have been identified in clonal hematopoiesis and myeloid neoplasms, with a striking enrichment in patients previously exposed to chemotherapy. In this study, we demonstrate that truncating PPM1D mutations confer a chemoresistance phenotype, resulting in the selective expansion of PPM1D-mutant hematopoietic cells in the presence of chemotherapy in vitro and in vivo. Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease mutational profiling of PPM1D in the presence of chemotherapy selected for the same exon 6 mutations identified in patient samples. These exon 6 mutations encode for a truncated protein that displays elevated expression and activity due to loss of a C-terminal degradation domain. Global phosphoproteomic profiling revealed altered phosphorylation of target proteins in the presence of the mutation, highlighting multiple pathways including the DNA damage response (DDR). In the presence of chemotherapy, PPM1D-mutant cells have an abrogated DDR resulting in altered cell cycle progression, decreased apoptosis, and reduced mitochondrial priming. We demonstrate that treatment with an allosteric, small molecule inhibitor of PPM1D reverts the phosphoproteomic, DDR, apoptotic, and mitochondrial priming changes observed in PPM1D-mutant cells. Finally, we show that the inhibitor preferentially kills PPM1D-mutant cells, sensitizes the cells to chemotherapy, and reverses the chemoresistance phenotype. These results provide an explanation for the enrichment of truncating PPM1D mutations in the blood of patients exposed to chemotherapy and in therapy-related myeloid neoplasms, and demonstrate that PPM1D can be a targeted in the prevention of clonal expansion of PPM1D-mutant cells and the treatment of PPM1D-mutant disease.

Increased neutrophil extracellular trap formation promotes thrombosis in myeloproliferative neoplasms.

Thrombosis is a major cause of morbidity and mortality in Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs), clonal disorders of hematopoiesis characterized by activated Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling. Neutrophil extracellular trap (NET) formation, a component of innate immunity, has been linked to thrombosis. We demonstrate that neutrophils from patients with MPNs are primed for NET formation, an effect blunted by pharmacological inhibition of JAK signaling. Mice with conditional knock-in of Jak2V617F, the most common molecular driver of MPN, have an increased propensity for NET formation and thrombosis. Inhibition of JAK-STAT signaling with the clinically available JAK2 inhibitor ruxolitinib abrogated NET formation and reduced thrombosis in a deep vein stenosis murine model. We further show that expression of PAD4, a protein required for NET formation, is increased in JAK2V617F-expressing neutrophils and that PAD4 is required for Jak2V617F-driven NET formation and thrombosis in vivo. Finally, in a population study of more than 10,000 individuals without a known myeloid disorder, JAK2V617F-positive clonal hematopoiesis was associated with an increased incidence of thrombosis. In aggregate, our results link JAK2V617F expression to NET formation and thrombosis and suggest that JAK2 inhibition may reduce thrombosis in MPNs through cell-intrinsic effects on neutrophil function.