Polymerization of high internal phase emulsions (polyHIPEs) is a well-established method for the production of high porosity foams. Researchers are often regulated to using a time-intensive trial and error approach to achieve target pore architectures. In this work, we performed a systematic study to identify the relative effects of common emulsion parameters on pore architecture (mixing speed, surfactant concentration, organic phase viscosity, molecular hydrophobicity). Across different macromer chemistries, the largest magnitude of change in pore size was observed across surfactant concentration (~6 fold, 5–20 wt%), whereas changing mixing speeds (~4 fold, 500–2000 RPM) displayed a reduced effect. Furthermore, it was observed that organic phase viscosity had a marked effect on pore size (~4 fold, 6–170 cP) with no clear trend observed with molecular hydrophobicity in this range (logP = 1.9–4.4). The efficacy of 1,4-butanedithiol as a reactive diluent was demonstrated and provides a means to reduce organic phase viscosity and increase pore size without affecting polymer fraction of the resulting foam. Overall, this systematic study of the microarchitectural effects of these macromers and processing variables provides a framework for the rational design of polyHIPE architectures that can be used to accelerate design and meet application needs across many sectors.

The scaffold pore size influences many critical physical aspects of tissue engineering, including tissue infiltration, biodegradation rate, and mechanical properties. Manual measurements of pore sizes from scanning electron micrographs using ImageJ/FIJI are commonly used to characterize scaffolds, but these methods are both time-consuming and subject to user bias. Current semi-automated analysis tools are limited by a lack of accessibility or limited sample size in their verification process. The work here describes the development of a new MATLAB algorithm, PoreScript, to address these limitations. The algorithm was verified using three common scaffold fabrication methods (e.g., salt leaching, gas foaming, emulsion templating) with varying pore sizes and shapes to demonstrate the versatility of this new tool. Our results demonstrate that the pore size characterization using PoreScript is comparable to manual pore size measurements. The PoreScript algorithm was further evaluated to determine the effect of user-input and image parameters (relative image magnification, pixel intensity threshold, and pore structure). Overall, this work validates the accuracy of the PoreScript algorithm across several fabrication methods and provides user-guidance for semi-automated image analysis and increased throughput of scaffold characterization.

The MRI-based Musculoskeletal Infection Reporting and Data System provides standardized terminology and recommended management of imaging findings of peripheral extremity infections.

Background: Most data linking chronic stress with cardiovascular disease (CVD) risk factors and outcomes have focused on single‐domain stress measurements. We evaluated the association between a novel composite measure of chronic perceived stress and CVD risk factors and outcomes in a diverse population. Methods and Results: Individual chronic stress subcomponents (generalized stress, psychosocial, financial, and neighborhood stress) were standardized and integrated to create a novel composite stress score (CSS). Participants from the DHS (Dallas Heart Study) phase 2 (2007–2009) visit without prevalent CVD who completed chronic stress questionnaires were included (n=2685). Associations between CSS and demographics, cardiac risk factors, and health behaviors were assessed in multivariable analyses. Cox proportional hazards models adjusting for traditional risk factors were used to determine associations of the CSS with adjudicated atherosclerotic CVD and global CVD (atherosclerotic CVD, heart failure, and atrial fibrillation) outcomes. CSS was higher among participants who were younger, women, and Black or Hispanic individuals, with lower income and educational attainment ( P <0.0001 for each). In multivariable regression models adjusting for age, sex, race and ethnicity, income and education, higher CSS associated with hypertension, smoking, higher body mass index, hemoglobin A _1C , high‐sensitivity C‐reactive protein, and sedentary time ( P <0.01 for each). Over a median follow‐up of 12.4 years, higher CSS associated with atherosclerotic CVD (adjusted hazard ratio [HR]. 1.22 per SD [95% CI, 1.01–1.47]) and global CVD (adjusted HR, 1.20 [95% CI, 1.03–1.40]). No interactions were seen between CSS, demographic factors, and outcomes. Conclusions: Composite measures of chronic stress are higher in vulnerable populations and may help identify individuals at risk for CVD who may benefit from enhanced prevention strategies.

Vasopressin regulates osmotic water transport in the renal collecting duct by PKA-mediated control of the water channel aquaporin-2 (AQP2). Collecting duct principal cells express two seemingly redundant PKA catalytic subunits, PKA catalytic α (PKA-Cα) and PKA catalytic β (PKA-Cβ). To identify the roles of these two protein kinases, we carried out deep phosphoproteomic analysis in cultured mpkCCD cells in which either PKA-Cα or PKA-Cβ was deleted using CRISPR-Cas9-based genome editing. Controls were cells carried through the genome editing procedure, but without deletion of PKA. TMT mass tagging was used for protein mass spectrometric quantification. Of the 4635 phosphopeptides that were quantified 67 were significantly altered in abundance with PKA-Cα deletion, while 21 were significantly altered in abundance with PKA-Cβ deletion. However, only four sites were changed in both. The target proteins identified in PKA-Cα-null cells were largely associated with cell membranes and membrane vesicles, while target proteins in the PKA-Cβ-null cells were largely associated with the actin cytoskeleton and cell junctions. In contrast, in vitro incubation of mpkCCD proteins with recombinant PKA-Cα and PKA-Cβ resulted in virtually identical phosphorylation changes. In addition, analysis of total protein abundances in the in vivo samples showed that PKA-Cα deletion resulted in a near disappearance of AQP2 protein, while PKA-Cβ deletion did not decrease AQP2 abundance. We conclude that PKA-Cα and PKA-Cβ serve substantially different functions in renal collecting duct cells and that differences in phosphorylation targets may be due to differences in protein interactions, e.g. mediated by AKAP, C-KAP or PDZ binding.

Background and Purpose: The peptide hormone vasopressin regulates water transport in the renal collecting duct largely via the V2 receptor, which triggers a cAMP-mediated activation of a protein kinase A (PKA)-dependent signaling network. The protein kinases downstream from PKA have not been fully identified or mapped to regulated phosphoproteins. Experimental Approach: We carried out systems-level analysis of large-scale phosphoproteomic data quantifying vasopressin-induced changes in phosphorylation in aquaporin-2-expressing cultured collecting duct cells (mpkCCD). Quantification was done using stable isotope labeling (SILAC method). Key Results: 9640 phosphopeptides were quantified. Stringent statistical analysis identified significant changes in response to vasopressin in 429 of these phosphopeptides. The corresponding phosphoproteins were mapped to known vasopressin-regulated cellular processes. The vasopressin-regulated sites were classified according to the sequences surrounding the phosphorylated amino acids giving 11 groups distinguished predominantly by the amino acids at positions +1, −3, −2 and −5 relative to the phosphorylated amino acid. Among the vasopressin-regulated phosphoproteins were 25 distinct protein kinases. Among these, six of them plus PKA appeared to account for phosphorylation of more than 80% of the 313 vasopressin-regulated phosphorylation sites. The six downstream kinases were salt-inducible kinase 2 (Sik2), cyclin-dependent kinase 18 (PCTAIRE-3, Cdk18), calmodulin-dependent kinase kinase 2 (Camkk2), protein kinase D2 (Prkd2), mitogen-activated kinase 3 (ERK1; Mapk3), and myosin light chain kinase (Mylk). Conclusion and Implications: In V2 receptor-mediated signaling, PKA is at the head of a complex network that includes at least 6 downstream vasopressin-regulated protein kinases that are prime targets for future study. The extensive phosphoproteomic data generated in this study is provided as a web-based data resource for future studies of G-protein coupled receptors.