Open data for COVID-19 policy analysis and mapping.

As the COVID-19 pandemic unfolded in the spring of 2020, governments around the world began to implement policies to mitigate and manage the outbreak. Significant research efforts were deployed to track and analyse these policies in real-time to better inform the response. While much of the policy analysis focused narrowly on social distancing measures designed to slow the spread of disease, here, we present a dataset focused on capturing the breadth of policy types implemented by jurisdictions globally across the whole-of-government. COVID Analysis and Mapping of Policies (COVID AMP) includes nearly 50,000 policy measures from 150 countries, 124 intermediate areas, and 235 local areas between January 2020 and June 2022. With up to 40 structured and unstructured characteristics encoded per policy, as well as the original source and policy text, this dataset provides a uniquely broad capture of the governance strategies for pandemic response, serving as a critical data source for future work in legal epidemiology and political science.

Emergency Department and Intensive Care Unit Overcrowding and Ventilator Shortages in US Hospitals During the COVID-19 Pandemic, 2020-2021.

OBJECTIVE: In 2020, the COVID-19 pandemic overburdened the US health care system because of extended and unprecedented patient surges and supply shortages in hospitals. We investigated the extent to which several US hospitals experienced emergency department (ED) and intensive care unit (ICU) overcrowding and ventilator shortages during the COVID-19 pandemic. METHODS: We analyzed Health Pulse data to assess the extent to which US hospitals reported alerts when experiencing ED overcrowding, ICU overcrowding, and ventilator shortages from March 7, 2020, through April 30, 2021. RESULTS: Of 625 participating hospitals in 29 states, 393 (63%) reported at least 1 hospital alert during the study period: 246 (63%) reported ED overcrowding, 239 (61%) reported ICU overcrowding, and 48 (12%) reported ventilator shortages. The number of alerts for overcrowding in EDs and ICUs increased as the number of COVID-19 cases surged. CONCLUSIONS: Timely assessment and communication about critical factors such as ED and ICU overcrowding and ventilator shortages during public health emergencies can guide public health response efforts in supporting federal, state, and local public health agencies.

Fifteen days in December: capture and analysis of Omicron-related travel restrictions.

Following the identification of the Omicron variant of the SARS-CoV-2 virus in late November 2021, governments worldwide took actions intended to minimise the impact of the new variant within their borders. Despite guidance from the WHO advising a risk-based approach, many rapidly implemented stringent policies focused on travel restrictions. In this paper, we capture 221 national-level travel policies issued during the 3 weeks following publicisation of the Omicron variant. We characterise policies based on whether they target travellers from specific countries or focus more broadly on enhanced screening, and explore differences in approaches at the regional level. We find that initial reactions almost universally focused on entry bans and flight suspensions from Southern Africa, and that policies continued to target travel from these countries even after community transmission of the Omicron variant was detected elsewhere in the world. While layered testing and quarantine requirements were implemented by some countries later in this 3-week period, these enhanced screening policies were rarely the first response. The timing and conditionality of quarantine and testing requirements were not coordinated between countries or regions, creating logistical complications and burdening travellers with costs. Overall, response measures were rarely tied to specific criteria or adapted to match the unique epidemiology of the new variant.

CDC's Flu on Call Simulation: Testing a National Helpline for Use During an Influenza Pandemic.

During an influenza pandemic, healthcare facilities are likely to be filled to capacity, leading to delays in seeing a provider and obtaining treatment. Flu on Call is a collaborative effort between the US Centers for Disease Control and Prevention and partners to develop a toll-free telephone helpline to reduce the burden on healthcare facilities and improve access to antivirals for people who are ill during an influenza pandemic. This study tested the feasibility of Flu on Call during a 1-day simulation using a severe pandemic scenario. Trained volunteer actors placed calls to the helpline using prepared scripts that were precoded for an expected outcome ("disposition") of the call. Scripts represented callers who were ill, those calling for someone else who was ill, and callers who were only seeking information. Information specialists and medical professionals managed the calls. Results demonstrated that Flu on Call may effectively assist callers during a pandemic, increase access to antiviral prescriptions, and direct patients to the appropriate level of care. Overall, 84% of calls exactly matched the expected call disposition; few calls (2%) were undermanaged (eg, the caller was ill but not transferred to a medical professional or received advice from the medical professional that was less intensive than what was warranted). Callers indicated a high level of satisfaction (83% reported their needs were met). Because of the high volume of calls that may be received during a severe pandemic, the Flu on Call platform should evolve to include additional triage channels (eg, through internet, chat, and/or text access).

Effectiveness of implementation strategies for venous leg ulcer guidelines: A systematic review.

BACKGROUND: The aim of clinical practice guidelines (CPGs) is to improve patient care; however inconsistencies between recommended practice and what actually happens in clinical practice continues. Venous Leg Ulcers (VLUs) have a significant negative impact on patients' quality of life and it is acknowledged that managing people with venous leg ulcers is protracted and costly. The aim of this review is to identify the most effective strategies to implement clinical practice guidelines for the management of VLUs by health care professionals in the hospital, outpatient, home and community setting. METHODS: A systematic review guided by methods from the Cochrane Effective Practice and Organisation of Care (EPOC) group was undertaken to identify implementation strategies for VLU clinical practice guidelines. Eligible studies were identified via systematic electronic searches of Medline, Embase, CINHAL and the Cochrane Library. RESULTS: We identified 142 potential studies of which one randomised controlled trial met the inclusion criteria. Following an analysis of the included study, it is not possible to recommend one implementation strategy over another when implementing practice guidelines for people with VLUs. CONCLUSION: We identified a limited evidence base for the effectiveness of implementation strategies for VLU CPGs. No one implementation strategy is better than another to facilitate VLU CPG implementation by health care professionals in hospital, outpatient, home or community settings.

Growth and Spatial Control of Murine Neural Stem Cells on Reflectin Films.

Stem cells have attracted significant attention due to their regenerative capabilities and their potential for the treatment of disease. Consequently, significant research effort has focused on the development of protein- and polypeptide-based materials as stem cell substrates and scaffolds. Here, we explore the ability of reflectin, a cephalopod structural protein, to support the growth of murine neural stem/progenitor cells (mNSPCs). We observe that the binding, growth, and differentiation of mNSPCs on reflectin films is comparable to that on more established protein-based materials. Moreover, we find that heparin selectively inhibits the adhesion of mNSPCs on reflectin, affording spatial control of cell growth and leading to a >30-fold change in cell density on patterned substrates. The described findings highlight the potential utility of reflectin as a stem cell culture material.

Tracking the Flow of Funds in Global Health Security.

Countries, philanthropies, and private sector organizations have been actively investing in global health security around the world. However, despite the coordinated approach to funding within the Global Health Security Agenda, there is currently no well-established method to track the commitment and disbursal of funds for global health security from funders to recipients or to identify the activities supported by existing funding initiatives. To address this need, we developed the Global Health Security Tracking Dashboard. This interactive, publicly available, Web-based dashboard maps the flow of funds from funder to recipient and categorizes the target efforts of those funds, allowing users to identify patterns of influence and success in health security funding implementation. The dashboard provides an evidence-based approach for defining targets for future funding by identifying the areas in which funds have not yet been effectively allocated, showcasing successes, and providing a source of information to promote mutual accountability.

Strengthening health security: an intuitive and user-friendly tool to estimate country-level costs.

Member States of the WHO working to build capacity under the International Health Regulations (IHR) are advised to develop prioritised, costed plans to implement improvements based on the results of voluntary external assessments. Defining the costs associated with capacity building under the IHR, however, has challenged nations, funders and supporting organisations. Most current efforts to develop costed national action plans involve long-term engagements that may take weeks or months to complete. While these efforts have value in and of themselves, there is an urgent need for a rapid-use tool to provide cost estimates regardless of the level of expertise of the personnel assigned to the task. In this paper, we describe a tool that can-in a matter of hours-provide country-level cost estimates for capacity building under the IHR. This paper also describes how the tool can be used in countries, as well as the challenges inherent in any costing process.

Decision support for evidence-based integration of disease control: A proof of concept for malaria and schistosomiasis.

AUTHOR SUMMARY: Designing and implementing effective programs for infectious disease control requires complex decision-making, informed by an understanding of the diseases, the types of disease interventions and control measures available, and the disease-relevant characteristics of the local community. Though disease modeling frameworks have been developed to address these questions and support decision-making, the complexity of current models presents a significant barrier to on-the-ground end users. The picture is further complicated when considering approaches for integration of different disease control programs, where co-infection dynamics, treatment interactions, and other variables must also be taken into account. Here, we describe the development of an application available on the internet with a simple user interface, to support on-the-ground decision-making for integrating disease control, given local conditions and practical constraints. The model upon which the tool is built provides predictive analysis for the effectiveness of integration of schistosomiasis and malaria control, two diseases with extensive geographical and epidemiological overlap. This proof-of-concept method and tool demonstrate significant progress in effectively translating the best available scientific models to support pragmatic decision-making on the ground, with the potential to significantly increase the impact and cost-effectiveness of disease control.

Self-Assembly of the Cephalopod Protein Reflectin.

Films from the cephalopod protein reflectin demonstrate multifaceted functionality as infrared camouflage coatings, proton transport media, and substrates for growth of neural stem cells. A detailed study of the in vitro formation, structural characteristics, and stimulus response of such films is presented. The reported observations hold implications for the design and development of advanced cephalopod-inspired functional materials.

Shank-cortactin interactions control actin dynamics to maintain flexibility of neuronal spines and synapses.

The family of Shank scaffolding molecules (comprising Shank1, 2 and 3) are core components of the postsynaptic density (PSD) in neuronal synapses. Shanks link surface receptors to other scaffolding molecules within the PSD, as well as to the actin cytoskeleton. However, determining the function of Shank proteins in neurons has been complicated because the different Shank isoforms share a very high degree of sequence and domain homology. Therefore, to control Shank content while minimizing potential compensatory effects, a miRNA-based knockdown strategy was developed to reduce the expression of all synaptically targeted Shank isoforms simultaneously in rat hippocampal neurons. Using this approach, a strong (>75%) reduction in total Shank protein levels was achieved at individual dendritic spines, prompting an approximately 40% decrease in mushroom spine density. Furthermore, Shank knockdown reduced spine actin levels and increased sensitivity to the actin depolymerizing agent Latrunculin A. A SHANK2 mutant lacking the proline-rich cortactin-binding motif (SHANK2-ΔPRO) was unable to rescue these defects. Furthermore, Shank knockdown reduced cortactin levels in spines and increased the mobility of spine cortactin as measured by single-molecule tracking photoactivated localization microscopy, suggesting that Shank proteins recruit and stabilize cortactin at the synapse. Furthermore, it was found that Shank knockdown significantly reduced spontaneous remodelling of synapse morphology that could not be rescued by the SHANK2-ΔPRO mutant. It was concluded that Shank proteins are key intermediates between the synapse and the spine interior that, via cortactin, permit the actin cytoskeleton to dynamically regulate synapse morphology and function.

Differentiation of human ESCs to retinal ganglion cells using a CRISPR engineered reporter cell line.

Retinal ganglion cell (RGC) injury and cell death from glaucoma and other forms of optic nerve disease is a major cause of irreversible vision loss and blindness. Human pluripotent stem cell (hPSC)-derived RGCs could provide a source of cells for the development of novel therapeutic molecules as well as for potential cell-based therapies. In addition, such cells could provide insights into human RGC development, gene regulation, and neuronal biology. Here, we report a simple, adherent cell culture protocol for differentiation of hPSCs to RGCs using a CRISPR-engineered RGC fluorescent reporter stem cell line. Fluorescence-activated cell sorting of the differentiated cultures yields a highly purified population of cells that express a range of RGC-enriched markers and exhibit morphological and physiological properties typical of RGCs. Additionally, we demonstrate that aligned nanofiber matrices can be used to guide the axonal outgrowth of hPSC-derived RGCs for in vitro optic nerve-like modeling. Lastly, using this protocol we identified forskolin as a potent promoter of RGC differentiation.

Insulin-Producing Endocrine Cells Differentiated In Vitro From Human Embryonic Stem Cells Function in Macroencapsulation Devices In Vivo.

UNLABELLED: The PEC-01 cell population, differentiated from human embryonic stem cells (hESCs), contains pancreatic progenitors (PPs) that, when loaded into macroencapsulation devices (to produce the VC-01 candidate product) and transplanted into mice, can mature into glucose-responsive insulin-secreting cells and other pancreatic endocrine cells involved in glucose metabolism. We modified the protocol for making PEC-01 cells such that 73%-80% of the cell population consisted of PDX1-positive (PDX1+) and NKX6.1+ PPs. The PPs were further differentiated to islet-like cells (ICs) that reproducibly contained 73%-89% endocrine cells, of which approximately 40%-50% expressed insulin. A large fraction of these insulin-positive cells were single hormone-positive and expressed the transcription factors PDX1 and NKX6.1. To preclude a significant contribution of progenitors to the in vivo function of ICs, we used a simple enrichment process to remove remaining PPs, yielding aggregates that contained 93%-98% endocrine cells and 1%-3% progenitors. Enriched ICs, when encapsulated and implanted into mice, functioned similarly to the VC-01 candidate product, demonstrating conclusively that in vitro-produced hESC-derived insulin-producing cells can mature and function in vivo in devices. A scaled version of our suspension culture was used, and the endocrine aggregates could be cryopreserved and retain functionality. Although ICs expressed multiple important ß cell genes, the cells contained relatively low levels of several maturity-associated markers. Correlating with this, the time to function of ICs was similar to PEC-01 cells, indicating that ICs required cell-autonomous maturation after delivery in vivo, which would occur concurrently with graft integration into the host. SIGNIFICANCE: Type 1 diabetes (T1D) affects approximately 1.25 million people in the U.S. alone and is deadly if not managed with insulin injections. This paper describes the production of insulin-producing cells in vitro and a new protocol for producing the cells, representing another potential cell source for a diabetes cell therapy. These cells can be loaded into a protective device that is implanted under the skin. The device is designed to protect the cells from immune rejection by the implant recipient. The implant can engraft and respond to glucose by secreting insulin, thus potentially replacing the ß cells lost in patients with T1D.

Tolerance induction and reversal of diabetes in mice transplanted with human embryonic stem cell-derived pancreatic endoderm.

Type 1 diabetes (T1D) is an autoimmune disease caused by T cell-mediated destruction of insulin-producing ß cells in the islets of Langerhans. In most cases, reversal of disease would require strategies combining islet cell replacement with immunotherapy that are currently available only for the most severely affected patients. Here, we demonstrate that immunotherapies that target T cell costimulatory pathways block the rejection of xenogeneic human embryonic-stem-cell-derived pancreatic endoderm (hESC-PE) in mice. The therapy allowed for long-term development of hESC-PE into islet-like structures capable of producing human insulin and maintaining normoglycemia. Moreover, short-term costimulation blockade led to robust immune tolerance that could be transferred independently of regulatory T cells. Importantly, costimulation blockade prevented the rejection of allogeneic hESC-PE by human PBMCs in a humanized model in vivo. These results support the clinical development of hESC-derived therapy, combined with tolerogenic treatments, as a sustainable alternative strategy for patients with T1D.

A scalable system for production of functional pancreatic progenitors from human embryonic stem cells.

Development of a human embryonic stem cell (hESC)-based therapy for type 1 diabetes will require the translation of proof-of-principle concepts into a scalable, controlled, and regulated cell manufacturing process. We have previously demonstrated that hESC can be directed to differentiate into pancreatic progenitors that mature into functional glucose-responsive, insulin-secreting cells in vivo. In this study we describe hESC expansion and banking methods and a suspension-based differentiation system, which together underpin an integrated scalable manufacturing process for producing pancreatic progenitors. This system has been optimized for the CyT49 cell line. Accordingly, qualified large-scale single-cell master and working cGMP cell banks of CyT49 have been generated to provide a virtually unlimited starting resource for manufacturing. Upon thaw from these banks, we expanded CyT49 for two weeks in an adherent culture format that achieves 50-100 fold expansion per week. Undifferentiated CyT49 were then aggregated into clusters in dynamic rotational suspension culture, followed by differentiation en masse for two weeks with a four-stage protocol. Numerous scaled differentiation runs generated reproducible and defined population compositions highly enriched for pancreatic cell lineages, as shown by examining mRNA expression at each stage of differentiation and flow cytometry of the final population. Islet-like tissue containing glucose-responsive, insulin-secreting cells was generated upon implantation into mice. By four- to five-months post-engraftment, mature neo-pancreatic tissue was sufficient to protect against streptozotocin (STZ)-induced hyperglycemia. In summary, we have developed a tractable manufacturing process for the generation of functional pancreatic progenitors from hESC on a scale amenable to clinical entry.

Subsynaptic AMPA receptor distribution is acutely regulated by actin-driven reorganization of the postsynaptic density.

AMPA receptors (AMPARs) mediate synaptic transmission and plasticity during learning, development, and disease. Mechanisms determining subsynaptic receptor position are poorly understood but are key determinants of quantal size. We used a series of live-cell, high-resolution imaging approaches to measure protein organization within single postsynaptic densities in rat hippocampal neurons. By photobleaching receptors in synapse subdomains, we found that most AMPARs do not freely diffuse within the synapse, indicating they are embedded in a matrix that determines their subsynaptic position. However, time lapse analysis revealed that synaptic AMPARs are continuously repositioned in concert with plasticity of this scaffold matrix rather than simply by free diffusion. Using a fluorescence correlation analysis, we found that across the lateral extent of single PSDs, component proteins were differentially distributed, and this distribution was continually adjusted by actin treadmilling. The C-terminal PDZ ligand of GluA1 did not regulate its mobility or distribution in the synapse. However, glutamate receptor activation promoted subsynaptic mobility. Strikingly, subsynaptic immobility of both AMPARs and scaffold molecules remained essentially intact even after loss of actin filaments. We conclude that receptors are actively repositioned at the synapse by treadmilling of the actin cytoskeleton, an influence which is transmitted only indirectly to receptors via the pliable and surprisingly dynamic internal structure of the PSD.

Lateral organization of the postsynaptic density.

Fast excitatory synaptic transmission is mediated by AMPA-type glutamate receptors (AMPARs). It is widely accepted that the number of AMPARs in the postsynaptic density (PSD) critically determines the efficiency of synaptic transmission, but an unappreciated aspect of synapse organization is the lateral positioning of AMPARs within the PSD, that is, their distribution across the face of a single synapse. Receptor lateral positioning is important in a number of processes, most notably because alignment with presynaptic release sites heavily influences the probability of receptor activation. In this review, we summarize current understanding of the mechanisms that dynamically control the subsynaptic positioning of AMPARs. This field is still at early stages, but the recent wave of developments in super-resolution microscopy, synapse tomography, and computational modeling now enable the study of lateral protein distribution and dynamics within the nanometer-scale boundaries of the PSD. We discuss data available measuring the lateral distribution of glutamate receptors and scaffold proteins within the PSD, and discuss potential mechanisms that might give rise to these patterns. Elucidating the mechanisms that underlie the lateral organization of the PSD will be critical to improve our understanding of synaptic processes whose disruption may be unexpectedly important in neurological disorders. This article is part of a Special Issue entitled Membrane Trafficking and Cytoskeletal Dynamics in 'Neuronal Function'.

A network of networks: cytoskeletal control of compartmentalized function within dendritic spines.

Almost 30 years ago, actin was identified as the major cytoskeletal component of dendritic spines. Since then, its role in the remarkable dynamics of spine morphology have been detailed with live-cell views establishing that spine shape dynamics are an important requirement for synaptogenesis and synaptic plasticity. However, the actin cytoskeleton is critical to numerous and varied processes within the spine which contribute to the maintenance and plasticity of synaptic function. Here, we argue that the spatial and temporal distribution of actin-dependent processes within spines suggests that the spine cytoskeleton should not be considered a single entity, but an interacting network of nodes or hubs that are independently regulated and balanced to maintain synapse function. Disruptions of this balance within the spine are likely to lead to psychiatric and neurological dysfunction.

Structural plasticity with preserved topology in the postsynaptic protein network.

The size, shape, and molecular arrangement of the postsynaptic density (PSD) determine the function of excitatory synapses in the brain. Here, we directly measured the internal dynamics of scaffold proteins within single living PSDs, focusing on the principal scaffold protein PSD-95. We found that individual PSDs undergo rapid, continuous changes in morphology driven by the actin cytoskeleton and regulated by synaptic activity. This structural plasticity is accompanied by rapid fluctuations in internal scaffold density over submicron distances. Using targeted photobleaching and photoactivation of PSD subregions, we show that PSD-95 is nearly immobile within the PSD, and PSD subdomains can be maintained over long periods. We propose a flexible matrix model of the PSD based on stable molecular positioning of PSD-95 scaffolds.