Coacervate or precipitate? Formation of non-equilibrium microstructures in coacervate emulsions.

Non-equilibrium processing of aqueous polyelectrolyte complex (PEC) coacervates is critical to many applications. In particular, many coacervate-forming systems are known to become trapped in out-of-equilibrium states (e.g., precipitation). The mechanism and conditions under which these states form, and whether they age, is not clearly understood. Here, we elucidate the influence of processing on the PEC coarsening mechanism as it varies with flow during mixing for a model system of poly(allylamine hydrochloride) and poly(acrylic acid sodium salt) in water. We demonstrate that flow conditions can be used to toggle the formation of rough, precipitate-like aggregates of micron-scale PEC structures. These structures form at compositions with viscous-dominant equilibrium rheology, and observations of their formation via optical microscopy suggest that they comprise colloidal aggregates of PEC coacervate droplets. We further show that these aggregates exhibit micron-scale coarsening, with a mixing time-dependent characteristic aging time scale. The results show that the formation of precipitate-like structures is not solely determined by composition, but is instead highly sensitive to mass transport and colloidal instability effects. Our observations suggest that the details of mixing flow can provide non-equilibrium structural control of a broad range of PEC coacervate materials orthogonally to structure-property inspired polymeric design. We anticipate that these findings will open the door for future studies on the control of non-equilibrium PEC formation and structure.

A molecular signature for IL-10-producing Th1 cells in protozoan parasitic diseases.

Control of visceral leishmaniasis (VL) depends on proinflammatory Th1 cells that activate infected tissue macrophages to kill resident intracellular parasites. However, proinflammatory cytokines produced by Th1 cells can damage tissues and require tight regulation. Th1 cell IL-10 production is an important cell-autologous mechanism to prevent such damage. However, IL-10-producing Th1 (type 1 regulatory; Tr1) cells can also delay control of parasites and the generation of immunity following drug treatment or vaccination. To identify molecules to target in order to alter the balance between Th1 and Tr1 cells for improved antiparasitic immunity, we compared the molecular and phenotypic profiles of Th1 and Tr1 cells in experimental VL caused by Leishmania donovani infection of C57BL/6J mice. We also identified a shared Tr1 cell protozoan signature by comparing the transcriptional profiles of Tr1 cells from mice with experimental VL and malaria. We identified LAG3 as an important coinhibitory receptor in patients with VL and experimental VL, and we reveal tissue-specific heterogeneity of coinhibitory receptor expression by Tr1 cells. We also discovered a role for the transcription factor Pbx1 in suppressing CD4+ T cell cytokine production. This work provides insights into the development and function of CD4+ T cells during protozoan parasitic infections and identifies key immunoregulatory molecules.

STING activation promotes autologous type I interferon-dependent development of type 1 regulatory T cells during malaria.

The development of highly effective malaria vaccines and improvement of drug-treatment protocols to boost antiparasitic immunity are critical for malaria elimination. However, the rapid establishment of parasite-specific immune regulatory networks following exposure to malaria parasites hampers these efforts. Here, we identified stimulator of interferon genes (STING) as a critical mediator of type I interferon production by CD4+ T cells during blood-stage Plasmodium falciparum infection. The activation of STING in CD4+ T cells by cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) stimulated IFNB gene transcription, which promoted development of IL-10- and IFN-γ-coproducing CD4+ T (type I regulatory [Tr1]) cells. The critical role for type I IFN signaling for Tr1 cell development was confirmed in vivo using a preclinical malaria model. CD4+ T cell sensitivity to STING phosphorylation was increased in healthy volunteers following P. falciparum infection, particularly in Tr1 cells. These findings identified STING expressed by CD4+ T cells as an important mediator of type I IFN production and Tr1 cell development and activation during malaria.

Remote control of mechanochemical reactions under physiological conditions using biocompatible focused ultrasound.

External control of chemical reactions in biological settings with spatial and temporal precision is a grand challenge for noninvasive diagnostic and therapeutic applications. While light is a conventional stimulus for remote chemical activation, its penetration is severely attenuated in tissues, which limits biological applicability. On the other hand, ultrasound is a biocompatible remote energy source that is highly penetrant and offers a wide range of functional tunability. Coupling ultrasound to the activation of specific chemical reactions under physiological conditions, however, remains a challenge. Here, we describe a synergistic platform that couples the selective mechanochemical activation of mechanophore-functionalized polymers with biocompatible focused ultrasound (FUS) by leveraging pressure-sensitive gas vesicles (GVs) as acousto-mechanical transducers. The power of this approach is illustrated through the mechanically triggered release of covalently bound fluorogenic and therapeutic cargo molecules from polymers containing a masked 2-furylcarbinol mechanophore. Molecular release occurs selectively in the presence of GVs upon exposure to FUS under physiological conditions. These results showcase the viability of this system for enabling remote control of specific mechanochemical reactions with spatiotemporal precision in biologically relevant settings and demonstrate the translational potential of polymer mechanochemistry.

Designing Superlubricious Hydrogels from Spontaneous Peroxidation Gradients.

Hydrogels are hydrated three-dimensional networks of hydrophilic polymers that are commonly used in the biomedical industry due to their mechanical and structural tunability, biocompatibility, and similar water content to biological tissues. The surface structure of hydrogels polymerized through free-radical polymerization can be modified by controlling environmental oxygen concentrations, leading to the formation of a polymer concentration gradient. In this work, 17.5 wt % polyacrylamide hydrogels are polymerized in low (0.01 mol % O2) and high (20 mol % O2) oxygen environments, and their mechanical and tribological properties are characterized through microindentation, nanoindentation, and tribological sliding experiments. Without significantly reducing the elastic modulus of the hydrogel (E* ≈ 200 kPa), we demonstrate an order of magnitude reduction in friction coefficient (from µ = 0.021 ± 0.006 to µ = 0.002 ± 0.001) by adjusting polymerization conditions (e.g., oxygen concentration). A quantitative analytical model based on polyacrylamide chemistry and kinetics was developed to estimate the thickness and structure of the monomer conversion gradient, termed the "surface gel layer". We find that polymerizing hydrogels at high oxygen concentrations leads to the formation of a preswollen surface gel layer that is approximately five times thicker (t ≈ 50 µm) and four times less concentrated (≈ 6% monomer conversion) at the surface prior to swelling compared to low oxygen environments (t ≈ 10 µm, ≈ 20% monomer conversion). Our model could be readily modified to predict the preswollen concentration profile of the polyacrylamide gel surface layer for any reaction conditions─monomer and initiator concentration, oxygen concentration, reaction time, and reaction media depth─or used to select conditions that correspond to a certain desired surface gel layer profile.

IL-10-producing Th1 cells possess a distinct molecular signature in malaria

Control of intracellular parasites responsible for malaria requires host IFN-γ+T-bet+CD4+ T cells (Th1 cells) with IL-10 produced by Th1 cells to mitigate the pathology induced by this inflammatory response. However, these IL-10-producing Th1 (induced type I regulatory [Tr1]) cells can also promote parasite persistence or impair immunity to reinfection or vaccination. Here, we identified molecular and phenotypic signatures that distinguished IL-10-Th1 cells from IL-10+Tr1 cells in Plasmodium falciparum-infected people who participated in controlled human malaria infection studies, as well as C57BL/6 mice with experimental malaria caused by P. berghei ANKA. We also identified a conserved Tr1 cell molecular signature shared between patients with malaria, dengue, and graft-versus-host disease. Genetic manipulation of primary human CD4+ T cells showed that the transcription factor cMAF played an important role in the induction of IL-10, while BLIMP-1 promoted the development of human CD4+ T cells expressing multiple coinhibitory receptors. We also describe heterogeneity of Tr1 cell coinhibitory receptor expression that has implications for targeting these molecules for clinical advantage during infection. Overall, this work provides insights into CD4+ T cell development during malaria that offer opportunities for creation of strategies to modulate CD4+ T cell functions and improve antiparasitic immunity.

COPD Population in US Primary Care: Data From the Optimum Patient Care DARTNet Research Database and the Advancing the Patient Experience in COPD Registry.

PURPOSE: To describe demographic and clinical characteristics of chronic obstructive pulmonary disease patients managed in US primary care. METHODS: This was an observational registry study using data from the Chronic Obstructive Pulmonary Disease (COPD) Optimum Patient Care DARTNet Research Database from which the Advancing the Patient Experience COPD registry is derived. Registry patients were aged ≥35 years at diagnosis. Electronic health record data were collected from both registries, supplemented with patient-reported information/outcomes from the Advancing the Patient Experience registry from 5 primary care groups in Texas, Ohio, Colorado, New York, and North Carolina (June 2019 through November 2020). RESULTS: Of 17,192 patients included, 1,354 were also in the Advancing the Patient Experience registry. Patients were predominantly female (56%; 9,689/17,192), White (64%; 9,732/15,225), current/ex-smokers (80%; 13,784/17,192), and overweight/obese (69%; 11,628/16,849). The most commonly prescribed maintenance treatments were inhaled corticosteroid with a long-acting ß2-agonist (30%) and inhaled corticosteroid with a long-acting muscarinic antagonist (27%). Although 3% (565/17,192) of patitents were untreated, 9% (1,587/17,192) were on short-acting bronchodilator monotherapy, and 4% (756/17,192) were on inhaled corticosteroid monotherapy. Despite treatment, 38% (6,579/17,192) of patients experienced 1 or more exacerbations in the last 12 months. These findings were mirrored in the Advancing Patient Experience registry with many patients reporting high or very high impact of disease on their health (43%; 580/1,322), a breathlessness score 2 or more (45%; 588/1,315), and 1 or more exacerbation in the last 12 months (50%; 646/1,294). CONCLUSIONS: Our findings highlight the high exacerbation, symptom, and treatment burdens experienced by COPD patients managed in US primary care, and the need for more real-life effectiveness trials to support decision making at the primary care level.

Variation in Demographic and Clinical Characteristics of Patients with COPD Receiving Care in US Primary Care: Data from the Advancing the Patient EXperience (APEX) in COPD Registry.

Introduction: Little is known about the variability in chronic obstructive pulmonary disease (COPD) management and how it may be affected by patient characteristics across different healthcare systems in the US. This study aims to describe demographic and clinical characteristics of people with COPD and compare management across five primary care medical groups in the US. Methods: This is a retrospective observational registry study utilizing electronic health records stored in the Advancing the Patient Experience (APEX) COPD registry. The APEX registry contains data from five US healthcare organizations located in Texas, Ohio, Colorado, New York, and North Carolina. Data on demographic and clinical characteristics of primary care patients with COPD between December 2019 and January 2020 were extracted and compared. Results: A total of 17,192 patients with COPD were included in analysis: Texas (n = 811), Ohio (n = 8722), Colorado (n = 472), New York (n = 1149) and North Carolina (n = 6038). The majority of patients at each location were female (>54%) and overweight/obese (>60%). Inter-location variabilities were noted in terms of age, race/ethnicity, exacerbation frequency, treatment pattern, and prevalence of comorbid conditions. Patients from the Colorado site experienced the lowest number of exacerbations per year while those from the New York site reported the highest number. Hypertension was the most common co-morbidity at 4 of 5 sites with the highest prevalence in New York. Depression was the most common co-morbidity in Ohio. Treatment patterns also varied by site; Colorado had the highest proportion of patients not on any treatment. ICS/LABA was the most commonly prescribed treatment except in Ohio, where ICS/LABA/LAMA was most common. Conclusions and Relevance: Our data show heterogeneity in demographic, clinical, and treatment characteristics of patients diagnosed with COPD who are managed in primary care across different healthcare organizations in the US.

High-throughput microscopy to determine morphology, microrheology, and phase boundaries applied to phase separating coacervates.

Evolution of composition, rheology, and morphology during phase separation in complex fluids is highly coupled to rheological and mass transport processes within the emerging phases, and understanding this coupling is critical for materials design of multiphase complex fluids. Characterizing these dependencies typically requires careful measurement of a large number of equilibrium and transport properties that are difficult to measure in situ as phase separation proceeds. Here, we propose and demonstrate a high-throughput microscopy platform to achieve simultaneous, in situ mapping of time-evolving morphology and microrheology in phase separating complex fluids over a large compositional space. The method was applied to a canonical example of polyelectrolyte complex coacervation, whereby mixing of oppositely charged species leads to liquid-liquid phase separation into distinct solute-dense and dilute phases. Morphology and rheology were measured simultaneously and kinetically after mixing to track the progression of phase separation. Once equilibrated, the dense phase viscosity was determined to high compositional accuracy using passive probe microrheology, and the results were used to derive empirical relationships between the composition and viscosity. These relationships were inverted to reconstruct the dense phase boundary itself, and further extended to other mixture compositions. The resulting predictions were validated by independent equilibrium compositional measurements. This platform paves the way for rapid screening and formulation of complex fluids and (bio)macromolecular materials, and serves as a critical link between formulation and rheology for multi-phase material discovery.

Comparing a Multimedia Digital Informed Consent Tool With Traditional Paper-Based Methods: Randomized Controlled Trial.

BACKGROUND: The traditional informed consent (IC) process rarely emphasizes research participants' comprehension of medical information, leaving them vulnerable to unknown risks and consequences associated with procedures or studies. OBJECTIVE: This paper explores how we evaluated the feasibility of a digital health tool called Virtual Multimedia Interactive Informed Consent (VIC) for advancing the IC process and compared the results with traditional paper-based methods of IC. METHODS: Using digital health and web-based coaching, we developed the VIC tool that uses multimedia and other digital features to improve the current IC process. The tool was developed on the basis of the user-centered design process and Mayer's cognitive theory of multimedia learning. This study is a randomized controlled trial that compares the feasibility of VIC with standard paper consent to understand the impact of interactive digital consent. Participants were recruited from the Winchester Chest Clinic at Yale New Haven Hospital in New Haven, Connecticut, and healthy individuals were recruited from the community using fliers. In this coordinator-assisted trial, participants were randomized to complete the IC process using VIC on the iPad or with traditional paper consent. The study was conducted at the Winchester Chest Clinic, and the outcomes were self-assessed through coordinator-administered questionnaires. RESULTS: A total of 50 participants were recruited in the study (VIC, n=25; paper, n=25). The participants in both groups had high comprehension. VIC participants reported higher satisfaction, higher perceived ease of use, higher ability to complete the consent independently, and shorter perceived time to complete the consent process. CONCLUSIONS: The use of dynamic, interactive audiovisual elements in VIC may improve participants' satisfaction and facilitate the IC process. We believe that using VIC in an ongoing, real-world study rather than a hypothetical study improved the reliability of our findings, which demonstrates VIC's potential to improve research participants' comprehension and the overall process of IC. TRIAL REGISTRATION: ClinicalTrials.gov NCT02537886; https://clinicaltrials.gov/ct2/show/NCT02537886.

Generation of a 100-billion cyclic peptide phage display library having a high skeletal diversity.

Phage display is a powerful technique routinely used for the generation of peptide- or protein-based ligands. The success of phage display selections critically depends on the size and structural diversity of the libraries, but the generation of large libraries remains challenging. In this work, we have succeeded in developing a phage display library comprising around 100 billion different (bi)cyclic peptides and thus more structures than any previously reported cyclic peptide phage display library. Building such a high diversity was achieved by combining a recently reported library cloning technique, based on whole plasmid PCR, with a small plasmid that facilitated bacterial transformation. The library cloned is based on 273 different peptide backbones and thus has a large skeletal diversity. Panning of the peptide repertoire against the important thrombosis target coagulation factor XI enriched high-affinity peptides with long consensus sequences that can only be found if the library diversity is large.

Design and characterization of a 3D-printed staggered herringbone mixer.

3D printing holds potential as a faster, cheaper alternative compared with traditional photolithography for the fabrication of microfluidic devices by replica molding. However, the influence of printing resolution and quality on device design and performance has yet to receive detailed study. Here, we investigate the use of 3D-printed molds to create staggered herringbone mixers (SHMs) with feature sizes ranging from ∼100 to 500 µm. We provide guidelines for printer calibration to ensure accurate printing at these length scales and quantify the impacts of print variability on SHM performance. We show that SHMs produced by 3D printing generate well-mixed output streams across devices with variable heights and defects, demonstrating that 3D printing is suitable and advantageous for low-cost, high-throughput SHM manufacturing.

Development and usability evaluation of VOICES: A digital health tool to identify elder mistreatment.

BACKGROUND/OBJECTIVES: A major barrier for society in overcoming elder mistreatment is an inability to accurately identify victims. There are several barriers to self-reporting elder mistreatment, including fear of nursing home placement or losing autonomy or a caregiver. Existing strategies to identify elder mistreatment neglect to empower those who experience it with tools for self-reporting. In this project, we developed and evaluated the usability of VOICES, a self-administrated digital health tool that screens, educates, and motivates older adults to self-report elder mistreatment. DESIGN: Cross-sectional study with User-Centered Design (UCD) approach. SETTING: Yale School of Medicine and the Agency on Aging of South-Central Connecticut. PARTICIPANTS: Thirty eight community-dwelling and cognitively intact older adults aged 60 years and older, caregivers, clinicians, and social workers. INTERVENTION: A tablet-based self-administrated digital health tool that screens, educates, and motivates older adults to self-report elder mistreatment. MEASUREMENTS: Qualitative and quantitative data were obtained from: (1) focus groups participants including: feedback from open-ended discussion, demographics, and a post-session survey; (2) usability evaluation including: demographics, usability measures, comfortability with technology, emotional state, and open-ended feedback. RESULTS: Focus group participants (n = 24) generally favored using a tablet-based tool to screen for elder mistreatment and expressed comfort answering questions on elder mistreatment using tablets. Usability evaluation participants (n = 14) overall scored VOICES a mean System Usability Scale (SUS) score of 86.6 (median = 88.8), higher than the benchmark SUS score of 68, indicating excellent ease of use. In addition, 93% stated that they would recommend the VOICES tool to others and 100% indicated understanding of VOICES' information and content. CONCLUSION: Our findings show that older adults are capable, willing, and comfortable with using the innovative and self-administrated digital tool for elder mistreatment screening. Our future plan is to conduct a feasibility study to evaluate the use of VOICES in identifying suspicion of mistreatment.

Advancing the Patient EXperience (APEX) in COPD Registry: Study Design and Strengths.

The Advancing the Patient Experience (APEX) in Chronic Obstructive Pulmonary Disease (COPD) registry (https://www.apexcopd.org/) is the first primary care health system-based COPD registry in the United States. While its ultimate goal is to improve the care of patients diagnosed with COPD, the registry is also designed to describe real-life experiences of people with COPD, track key outcomes longitudinally, and assess the effectiveness of interventions. It will retrospectively and prospectively collect information from 3000 patients enrolled in 5 health care organizations. Information will be obtained from electronic health records, and from extended annual and brief questionnaires completed by patients before clinic visits. Core variables to be collected into the APEX COPD registry were agreed on by Delphi consensus and fall into 3 domains: demographics, COPD monitoring, and treatment. Main strengths of the registry include: 1) its size and scope (in terms of patient numbers, geographic spread and use of multiple information sources including patient-reported information); 2) collection of variables which are clinically relevant and practical to collect within primary care; 3) use of electronic data capture systems to ensure high-quality data and minimization of data-entry requirements; 4) inclusion of clinical, database development, management and communication experts; 5) regular sharing of key findings, both at international/national congresses and in peer-reviewed publications; and 6) a robust organizational structure to ensure continuance of the registry, and that research outputs are ethical, relevant and continue to bring value to both patients and physicians.

Perceptions of older adults and health professionals about digital screening tools for elder mistreatment in the emergency department.

Background: Healthcare settings represent a missed opportunity to systematically identify and address mistreatment. Objective: Our objective was to obtain perspectives of older adults, caregivers, and emergency care providers regarding screening and intervention for elder mistreatment in the emergency department (ED) with a focus on utilizing digital health tools to facilitate the process. These findings will inform the development of a Web-based, digital health tool optimized for a tablet device to educate, screen, and facilitate reporting of elder mistreatment among patients presenting to the ED. Method: We conducted a qualitative study utilizing three in-person focus groups (N=31) with older adults from the community, caregivers for older adults, and clinicians and social workers who worked in the ED. Using a semi-structured interview guide, we identified attitudes about the process of divulging abuse, attitudes towards the ED as the location for screening and information delivery, and perceptions of digital tools for screening and information. Results: Participants identified numerous challenges to the disclosure of mistreatment, including feelings of vulnerability and concerns about losing their homes, social supports, and connection to caregivers. In contrast, they were uncertain about the benefits of disclosure. Digital tools were seen as helpful in terms of overcoming numerous challenges to screening, but participants suggested maintaining a human element to interactions. Conclusion: While challenges to elder mistreatment screening were identified, participants had recommendations for optimizing such efforts and responded positively to digital health tools as a means of screening.

Development of the Advancing the Patient Experience in COPD Registry: A Modified Delphi Study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is commonly managed by family physicians, but little is known about specifics of management and how this may be improved. The Advancing the Patient Experience in COPD (APEX COPD) registry will be the first U.S. primary care, health system-based registry following patients diagnosed with COPD longitudinally, using a standardized set of variables to investigate how patients are managed in real life and assess outcomes of various management strategies. OBJECTIVE: Gaining expert consensus on a standardized list of variables to capture in the APEX COPD registry. METHODS: A modified, Delphi process was used to reach consensus on which data to collect in the registry from electronic health records (EHRs), patient-reported information (PRI) and patient-reported outcomes (PRO), and by physicians during subsequent office visits. The Delphi panel comprised 14 primary care and specialty COPD experts from the United States and internationally. The process consisted of 3 iterative rounds. Responses were collected electronically. RESULTS: Of the initial 195 variables considered, consensus was reached to include up to 115 EHR variables, 34 PRI/PRO variables and 5 office-visit variables in the APEX COPD registry. These should include information on symptom burden, diagnosis, COPD exacerbations, lung function, quality of life, comorbidities, smoking status/history, treatment specifics (including side effects), inhaler management, and patient education/self-management. CONCLUSION: COPD experts agreed upon the core variables to collect from EHR data and from patients to populate the APEX COPD registry. Data will eventually be integrated, standardized and stored in the APEX COPD database and used for approved COPD-related research.

IL-27 signalling regulates glycolysis in Th1 cells to limit immunopathology during infection.

Inflammation is critical for controlling pathogens, but also responsible for symptoms of infectious diseases. IL-27 is an important regulator of inflammation and can limit development of IFNγ-producing Tbet+ CD4+ T (Th1) cells. IL-27 is thought to do this by stimulating IL-10 production by CD4+ T cells, but the underlying mechanisms of these immunoregulatory pathways are not clear. Here we studied the role of IL-27 signalling in experimental visceral leishmaniasis (VL) caused by infection of C57BL/6 mice with the human pathogen Leishmania donovani. We found IL-27 signalling was critical for the development of IL-10-producing Th1 (Tr1) cells during infection. Furthermore, in the absence of IL-27 signalling, there was improved control of parasite growth, but accelerated splenic pathology characterised by the loss of marginal zone macrophages. Critically, we discovered that IL-27 signalling limited glycolysis in Th1 cells during infection that in turn attenuated inflammation. Furthermore, the modulation of glycolysis in the absence of IL-27 signalling restricted tissue pathology without compromising anti-parasitic immunity. Together, these findings identify a novel mechanism by which IL-27 mediates immune regulation during disease by regulating cellular metabolism.

The NK cell granule protein NKG7 regulates cytotoxic granule exocytosis and inflammation.

Immune-modulating therapies have revolutionized the treatment of chronic diseases, particularly cancer. However, their success is restricted and there is a need to identify new therapeutic targets. Here, we show that natural killer cell granule protein 7 (NKG7) is a regulator of lymphocyte granule exocytosis and downstream inflammation in a broad range of diseases. NKG7 expressed by CD4+ and CD8+ T cells played key roles in promoting inflammation during visceral leishmaniasis and malaria-two important parasitic diseases. Additionally, NKG7 expressed by natural killer cells was critical for controlling cancer initiation, growth and metastasis. NKG7 function in natural killer and CD8+ T cells was linked with their ability to regulate the translocation of CD107a to the cell surface and kill cellular targets, while NKG7 also had a major impact on CD4+ T cell activation following infection. Thus, we report a novel therapeutic target expressed on a range of immune cells with functions in different immune responses.