Recognising the importance and impact of Imaging Scientists: Global guidelines for establishing career paths within core facilities.

In the dynamic landscape of scientific research, imaging core facilities are vital hubs propelling collaboration and innovation at the technology development and dissemination frontier. Here, we present a collaborative effort led by Global BioImaging (GBI), introducing international recommendations geared towards elevating the careers of Imaging Scientists in core facilities. Despite the critical role of Imaging Scientists in modern research ecosystems, challenges persist in recognising their value, aligning performance metrics and providing avenues for career progression and job security. The challenges encompass a mismatch between classic academic career paths and service-oriented roles, resulting in a lack of understanding regarding the value and impact of Imaging Scientists and core facilities and how to evaluate them properly. They further include challenges around sustainability, dedicated training opportunities and the recruitment and retention of talent. Structured across these interrelated sections, the recommendations within this publication aim to propose globally applicable solutions to navigate these challenges. These recommendations apply equally to colleagues working in other core facilities and research institutions through which access to technologies is facilitated and supported. This publication emphasises the pivotal role of Imaging Scientists in advancing research programs and presents a blueprint for fostering their career progression within institutions all around the world.

Establishing a national strategy for shared research resources in biomedical sciences.

Contemporary science has become increasingly multi-disciplinary and team-based, resulting in unprecedented growth in biomedical innovation and technology over the last several decades. Collaborative research efforts have enabled investigators to respond to the demands of an increasingly complex 21st century landscape, including pressing scientific challenges such as the COVID-19 pandemic. A major contributing factor to the success of team science is the mobilization of core facilities and shared research resources (SRRs), the scientific instrumentation and expertise that exist within research organizations that enable widespread access to advanced technologies for trainees, faculty, and staff. For over 40 years, SRRs have played a key role in accelerating biomedical research discoveries, yet a national strategy that addresses how to leverage these resources to enhance team science and achieve shared scientific goals is noticeably absent. We believe a national strategy for biomedical SRRs-led by the National Institutes of Health-is crucial to advance key national initiatives, enable long-term research efficiency, and provide a solid foundation for the next generation of scientists.

NUcore at 10: A Decade of Experience Developing a Core Facilities Management Application.

Implementing an effective software solution is an important step in managing a portfolio of core facilities. Though commercial options are available, developing or adopting a custom platform is a viable path for many institutions. At Northwestern University (NU), the cores program was reorganized beginning in 2008, and we pursued the latter path in order to retain control of the development priorities and to ensure integration with other enterprise systems. This manuscript describes our experience and results after a decade of effort. The platform, named NUcore, began enrollment in 2011, and full enrollment was achieved in 2019. Key features of NUcore include a stable and secure environment, a responsive and intuitive interface for users and core staff, seamless integration with the university financial system, rules and restrictions to ensure compliance, and both core-specific and enterprise reporting. NUcore now supports nearly half of all sponsored award dollars at NU at a cost of only 1 cent per dollar of business transacted. On average, there are over 4000 active users each year. NUcore is managed as an open-source project, available at no cost to any organization. Five academic organizations currently use the NUcore code base. For NU, NUcore has been a substantial success, and continuous development will ensure that it meets the future needs of our university and its cores.

Building a Sustainable Portfolio of Core Facilities: a Case Study.

Core facilities are an integral component of modern research institutions. Here, we describe our efforts over the past decade to build a sustainable portfolio of core facilities at Northwestern University. Through careful strategic planning, coordination, investment, and oversight, we have developed a model for managing core facilities that addresses researchers' needs within 3 schools across 2 campuses. Our management model is a partnership between core directors and central administrators that maintains operational control of each facility at the local level to ensure that the needs of researchers are being addressed. Central administrative oversight ensures that facilities are compliant with federal regulations, are financially sound, and align with institutional priorities. This hybrid management model is comprised of 4 pillars that are essential and necessary to ensure the long-term viability and success of facilities: core personnel, core space, institutional investment, and institutional evaluation. With these pillars in place, our facilities are well positioned to fulfill their key value propositions, to demonstrate a robust return on the university's investment, and to ensure that facilities remain vibrant, sustainable components of the research ecosystem for the foreseeable future.

Metrics for Success: Strategies for Enabling Core Facility Performance and Assessing Outcomes.

Core Facilities are key elements in the research portfolio of academic and private research institutions. Administrators overseeing core facilities (core administrators) require assessment tools for evaluating the need and effectiveness of these facilities at their institutions. This article discusses ways to promote best practices in core facilities as well as ways to evaluate their performance across 8 of the following categories: general management, research and technical staff, financial management, customer base and satisfaction, resource management, communications, institutional impact, and strategic planning. For each category, we provide lessons learned that we believe contribute to the effective and efficient overall management of core facilities. If done well, we believe that encouraging best practices and evaluating performance in core facilities will demonstrate and reinforce the importance of core facilities in the research and educational mission of institutions. It will also increase job satisfaction of those working in core facilities and improve the likelihood of sustainability of both facilities and personnel.

Best practices for core facilities: handling external customers.

This article addresses the growing interest among U.S. scientific organizations and federal funding agencies in strengthening research partnerships between American universities and the private sector. It outlines how core facilities at universities can contribute to this partnership by offering services and access to high-end instrumentation to both nonprofit organizations and commercial organizations. We describe institutional policies (best practices) and procedures (terms and conditions) that are essential for facilitating and enabling such partnerships. In addition, we provide an overview of the relevant federal regulations that apply to external use of academic core facilities and offer a set of guidelines for handling them. We conclude by encouraging directors and managers of core facilities to work with the relevant organizational offices to promote and nurture such partnerships. If handled appropriately, we believe such partnerships can be a win-win situation for both organizations that will support research and bolster the American economy.

Imaging of mitochondrial and non-mitochondrial responses in cultured rat hippocampal neurons exposed to micromolar concentrations of TMRM.

Tetramethylrhodamine methyl ester (TMRM) is a fluorescent dye used to study mitochondrial function in living cells. Previously, we reported that TMRM effectively labeled mitochondria of neurons deep within mouse brain slices. Use of micromolar concentration of dye, which was required to get sufficient staining for two-photon imaging, resulted in typical fluctuations of TMRM. With prolonged exposure, we recorded additional responses in some neurons that included slow oscillations and propagating waves of fluorescence. (Note: We use the terms "fluctuation" to refer to a change in the fluorescent state of an individual mitochondrion, "oscillation" to refer to a localized change in fluorescence in the cytosol, and "wave" to refer to a change in cytosolic fluorescence that propagated within a cell. Use of these terms does not imply any underlying periodicity.) In this report we describe similar results using cultured rat hippocampal neurons. Prolonged exposure of cultures to 2.5 µM TMRM produced a spontaneous increase in fluorescence in some neurons, but not glial cells, after 45-60 minutes that was followed by slow oscillations, waves, and eventually apoptosis. Spontaneous increases in fluorescence were insensitive to high concentrations of FCCP (100 µM) and thapsigargin (10 µM) indicating that they originated, at least in part, from regions outside of mitochondria. The oscillations did not correlate with changes in intracellular Ca(2+), but did correlate with differences in fluorescence lifetime of the dye. Fluorescence lifetime and one-photon ratiometric imaging of TMRM suggested that the spontaneous increase and subsequent oscillations were due to movement of dye between quenched (hydrophobic) and unquenched (hydrophilic) compartments. We propose that these movements may be correlates of intracellular events involved in early stages of apoptosis.

Galectin-3 maintains cell motility from the subventricular zone to the olfactory bulb.

The adult brain subventricular zone (SVZ) produces neuroblasts that migrate through the rostral migratory stream (RMS) to the olfactory bulb (OB) in a specialized niche. Galectin-3 (Gal-3) regulates proliferation and migration in cancer and is expressed by activated macrophages after brain injury. The function of Gal-3 in the normal brain is unknown, but we serendipitously found that it was expressed by ependymal cells and SVZ astrocytes in uninjured mice. Ependymal cilia establish chemotactic gradients and astrocytes form glial tubes, which combine to aid neuroblast migration. Whole-mount preparations and electron microscopy revealed that both ependymal cilia and SVZ astrocytes were disrupted in Gal3(-/-) mice. Interestingly, far fewer new BrdU(+) neurons were found in the OB of Gal3(-/-) mice, than in wild-type mice 2 weeks after labeling. However, SVZ proliferation and cell death, as well as OB differentiation rates were unaltered. This suggested that decreased migration in vivo was sufficient to decrease the number of new OB neurons. Two-photon time-lapse microscopy in forebrain slices confirmed decreased migration; cells were slower and more exploratory in Gal3(-/-) mice. Gal-3 blocking antibodies decreased migration and dissociated neuroblast cell-cell contacts, whereas recombinant Gal-3 increased migration from explants. Finally, we showed that expression of phosphorylated epidermal growth factor receptor (EGFR) was increased in Gal3(-/-) mice. These results suggest that Gal-3 is important in SVZ neuroblast migration, possibly through an EGFR-based mechanism, and reveals a role for this lectin in the uninjured brain.

Subventricular zone cell migration: lessons from quantitative two-photon microscopy.

Neuroblasts born in the adult subventricular zone (SVZ) migrate long distances in the rostral migratory stream (RMS) to the olfactory bulbs where they integrate into circuitry as functional interneurons. As very little was known about the dynamic parameters of SVZ neuroblast migration, we used two-photon time-lapse microscopy to analyze migration in acute slices. This involved analyzing 3D stacks of images over time and uncovered several novel aspects of SVZ migration: chains remain stable, cells can be immotile for extensive periods, morphology does not necessarily correlate with motility, neuroblasts exhibit local exploratory motility, dorsoventral migration occurs throughout the striatal SVZ, and neuroblasts turn at distinctive angles. We investigated these novel findings in the SVZ and RMS from the population to the single cell level. In this review we also discuss some technical considerations when setting up a two-photon microscope imaging system. Throughout the review we identify several unsolved questions about SVZ neuroblast migration that might be addressed with current or emerging techniques.

Rostral migratory stream neuroblasts turn and change directions in stereotypic patterns.

Neuroblasts generated in the adult subventricular zone (SVZ) migrate through the rostral migratory stream (RMS) to the olfactory bulb (OB). Previous work uncovered motility ranging from straight to complex, but it was unclear if directional changes were stochastic or exhibited stereotypical patterns. Here, we provide the first in-depth two-photon time-lapse microscopy study of morphological and dynamic features that accompany turning and direction reversals in the RMS. We identified three specific kinds of turning (30-90 degrees): bending of the leading process proximal to the cell body (P-bending 47% of cases), bending of the distal leading process (D-bending 30%) or branching of the leading process or lamellipodium (23%). Bending and branching angles were remarkably constrained and were significantly different from one another. Cells reversed direction (> 90 degrees) through D-bendings (54%), branching (11%) or de novo growth of processes from the soma (23%), but not P-bending. Direction reversal was often composed of several iterations of D-bending or branching as opposed to novel modalities. Individual neuroblasts could turn or change direction in multiple patterns suggesting that the patterns are not specific for different lineages. These findings show that neuroblasts in the RMS use a limited number of distinct and constrained modalities to turn or reverse direction.

MEF-2 regulates activity-dependent spine loss in striatopallidal medium spiny neurons.

Striatal dopamine depletion profoundly reduces the density of spines and corticostriatal glutamatergic synapses formed on D(2) dopamine receptor expressing striatopallidal medium spiny neurons, leaving D(1) receptor expressing striatonigral medium spiny neurons relatively intact. Because D(2) dopamine receptors diminish the excitability of striatopallidal MSNs, the pruning of synapses could be a form of homeostatic plasticity aimed at restoring activity into a preferred range. To characterize the homeostatic mechanisms controlling synapse density in striatal medium spiny neurons, striatum from transgenic mice expressing a D(2) receptor reporter construct was co-cultured with wild-type cerebral cortex. Sustained depolarization of these co-cultures induced a profound pruning of glutamatergic synapses and spines in striatopallidal medium spiny neurons. This pruning was dependent upon Ca(2+) entry through Cav1.2 L-type Ca(2+) channels, activation of the Ca(2+)-dependent protein phosphatase calcineurin and up-regulation of myocyte enhancer factor 2 (MEF2) transcriptional activity. Depolarization and MEF2 up-regulation increased the expression of two genes linked to synaptic remodeling-Nur77 and Arc. Taken together, these studies establish a translational framework within which striatal adaptations linked to the symptoms of Parkinson's disease can be explored.

Adult mouse subventricular zone stem and progenitor cells are sessile and epidermal growth factor receptor negatively regulates neuroblast migration.

BACKGROUND: The adult subventricular zone (SVZ) contains stem and progenitor cells that generate neuroblasts throughout life. Although it is well accepted that SVZ neuroblasts are migratory, recent evidence suggests their progenitor cells may also exhibit motility. Since stem and progenitor cells are proliferative and multipotential, if they were also able to move would have important implications for SVZ neurogenesis and its potential for repair. METHODOLOGY/PRINCIPAL FINDINGS: We studied whether SVZ stem and/or progenitor cells are motile in transgenic GFP+ slices with two photon time lapse microscopy and post hoc immunohistochemistry. We found that stem and progenitor cells; mGFAP-GFP+ cells, bright nestin-GFP+ cells and Mash1+ cells were stationary in the SVZ and rostral migratory stream (RMS). In our search for motile progenitor cells, we uncovered a population of motile betaIII-tubulin+ neuroblasts that expressed low levels of epidermal growth factor receptor (EGFr). This was intriguing since EGFr drives proliferation in the SVZ and affects migration in other systems. Thus we examined the potential role of EGFr in modulating SVZ migration. Interestingly, EGFr(low) neuroblasts moved slower and in more tortuous patterns than EGFr-negative neuroblasts. We next questioned whether EGFr stimulation affects SVZ cell migration by imaging Gad65-GFP+ neuroblasts in the presence of transforming growth factor alpha (TGF-alpha), an EGFr-selective agonist. Indeed, acute exposure to TGF-alpha decreased the percentage of motile cells by approximately 40%. CONCLUSIONS/SIGNIFICANCE: In summary, the present study directly shows that SVZ stem and progenitor cells are static, that EGFr is retained on some neuroblasts, and that EGFr stimulation negatively regulates migration. This result suggests an additional role for EGFr signaling in the SVZ.

Dynamic features of postnatal subventricular zone cell motility: a two-photon time-lapse study.

Neuroblasts migrate long distances in the postnatal subventricular zone (SVZ) and rostral migratory stream (RMS) to the olfactory bulbs. Many fundamental features of SVZ migration are still poorly understood, and we addressed several important questions using two-photon time-lapse microscopy of brain slices from postnatal and adult eGFP(+) transgenic mice. 1) Longitudinal arrays of neuroblasts, so-called chain migration, have never been dynamically visualized in situ. We found that neuroblasts expressing doublecortin-eGFP (Dcx-eGFP) and glutamic acid decarboxylase-eGFP (Gad-eGFP) remained within arrays, which maintained their shape for many hours, despite the fact that there was a wide variety of movement within arrays. 2) In the dorsal SVZ, neuroblasts migrated rostrocaudally as expected, but migration shifted to dorsoventral orientations throughout ventral regions of the lateral ventricle. 3) Whereas polarized bipolar morphology has been a gold standard for inferring migration in histologic sections, our data indicated that migratory morphology was not predictive of motility. 4) Is there local motility in addition to long distance migration? 5) How fast is SVZ migration? Unexpectedly, one-third of motile neuroblasts moved locally in complex exploratory patterns and at average speeds slower than long distance movement. 6) Finally, we tested, and disproved, the hypothesis that all motile cells in the SVZ express doublecortin, indicating that Dcx is not required for migration of all SVZ cell types. These data show that cell motility in the SVZ and RMS is far more complex then previously thought and involves multiple cell types, behaviors, speeds, and directions.

A Rationale and Outline for an Undergraduate Course on the Philosophy and History of Science for Life Science Students.

There are compelling reasons for teaching a philosophy of science course to undergraduate life science students. The main reason is to help them understand that modern science is not based upon a single, consistent philosophical system; nor is it based upon common sense, or a method, set of rules or formulas that can be used to make unerring predictions. Rather, science is a dynamic process that is constantly being modified and refined to reflect and encompass an ever-expanding set of hypotheses, observations, and theories. To illustrate these points, we developed a course that examined the history and philosophical underpinnings of modern science, and we discussed famous experiments that challenged the prevailing norm and led to Kuhnian revolutions in scientific thought. Building upon this knowledge, students investigated how different philosophical systems address controversial social issues in the biological sciences. They examined the teaching of intelligent design and creationism in public schools, the implications of legalized abortion and physician-assisted suicide, the potential impact of DNA fingerprinting on human rights and racism, the promise and pitfalls of stem cell research, and the neurobiological basis of consciousness and its relevance to mental health therapies and the animal rights movement. We believe undergraduate life science students should be exposed to these issues and have an opportunity to develop informed opinions about them before they graduate from college. Exploration of such topics will help them become better prepared for the inevitable public debates that they will face as science educators, researchers, and leaders of society.

(-)-Isoproterenol modulation of maxi-K(+) channel in nonpigmented ciliary epithelial cells through a G-protein gated pathway.

PURPOSE: Adrenergic agents decrease intraocular pressure by reducing aqueous humor secretion from ciliary epithelial cells. Since the ionic concentration of aqueous humor contributes to intraocular pressure, we have investigated the effect of (-)-isoproterenol, a beta-adrenergic agonist on the maxi-K( +) channel in rabbit nonpigmented ciliary epithelial (NPE) cells. METHODS: Single-channel currents were recorded from the basolateral surface of acutely isolated NPE cells using patch clamp techniques. RESULTS: A calcium dependent maxi-K(+) channel was identified in 31% of cell-attached patches. In the excised condition the channel was activated in presence of calcium. In symmetrical K(+) solution a linear current-voltage relationship and unitary conductance of 158 +/- 15 pS was observed. Replacing K(+) with Na(+) the current-voltage curve shifted to the right and approached a reversal potential for K( +) ( approximately -80 mV). Barium (2 mM) from the intracellular side or iberiotoxin (50 nM) from the extracellular side blocked the channel activity. In cell-attached patches, the beta-receptor agonist (-)-isoproterenol (2.5 microM) increased channel open probability (P(o)) only when applied directly through the patch pipette. beta(2)-adrenoceptor antagonists (ICI-118, 551, l-timolol) blocked the channel activity more efficiently than the beta(1)-adrenoceptor antagonist betaxolol. In excised patches, (-)-isoproterenol increased baseline P(o) 5-fold (0.5 +/- 0.13) when GTP (100 microM) and GTPgammaS (100 microM) were present at the cytosolic surface of the pipette (control; P(o), 0.12 +/- 0.006). GTP augmented baseline channel activity (0.1 +/- 0.004) 7-fold (0.7 +/- 0.03) when (-)-isoproterenol was included in patch pipette. CONCLUSIONS: Rabbit NPE cells expressed maxi-K(+) channels on their basolateral surface. The adrenergic agonist (-)-isoproterenol activated these channels via a beta(2)-adrenoceptor that was modulated by a direct G-protein gated pathway.