Pediatrician perspectives on barriers and facilitators to discharge instruction comprehension and adherence for parents of children with medical complexity.

BACKGROUND: High rates of posthospitalization errors are observed in children with medical complexity (CMC). Poor parent comprehension of and adherence to complex discharge instructions can contribute to errors. Pediatrician views on common barriers and facilitators to parent comprehension and adherence are understudied. OBJECTIVE: To examine pediatrician perspectives on barriers and facilitators experienced by parents in comprehension of and adherence to inpatient discharge instructions for CMC. DESIGN, SETTINGS, AND PARTICIPANTS: We conducted a qualitative, descriptive study of attending pediatricians (n = 20) caring for CMC in inpatient settings (United States and Canada) and belonging to listservs for pediatric hospitalists/complex care providers. We used purposive/maximum variation sampling to ensure heterogeneity (e.g., hospital, region). MAIN OUTCOME AND MEASURES: A multidisciplinary team designed and piloted a semistructured interview guide with pediatricians who care for CMC. Team members conducted semistructured interviews via phone or video call. Interviews were audiorecorded and transcribed. We analyzed transcripts using content analysis; codes were derived a priori from a conceptual framework (based on the Pediatric Self-Management Model) and a preliminary transcript analysis. We applied codes and identified emerging themes. RESULTS: Pediatricians identified three themes as barriers and facilitators to discharge instruction comprehension and adherence: (1) regimen complexity, (2) access to the healthcare team (e.g., inpatient team, outpatient pediatrician, home nursing) and resources (e.g., medications, medical equipment), and (3) need for a family centered and health literacy-informed approach to discharge planning and education. Next steps include the assessment of parent perspectives on barriers and facilitators to discharge instruction comprehension and adherence for prents of CMC and the development of intervention strategies.

Pharmacist-driven continuous glucose monitoring in community and ambulatory care pharmacy practice: A scoping review.

BACKGROUND: Continuous glucose monitoring (CGM) devices improve clinical outcomes and facilitate achieving patient-specific goals. However, opportunities and barriers to implementation of pharmacist-driven CGM services are not well-described. OBJECTIVES: This scoping review was conducted to identify opportunities and barriers to implementing pharmacist-driven CGM services in the community and ambulatory care setting. Clinical outcomes resulting from pharmacist-driven CGM were also explored. METHODS: A health librarian searched Ovid MEDLINE, Cochrane CENTRAL, Embase, Web of Science, Scopus, International Pharmaceutical Abstracts using keywords and subject headings from inception through December 2, 2022 to identify studies describing pharmacist or pharmacy-based CGM programs. No publication type, date limits, language restrictions, or other filters were applied. The database search was supplemented by a search of Google Scholar and a citation search of preselected gold standard articles. RESULTS: The scoping review initially identified 942 citations of which 249 passed abstract screening and 11 were included in the review. Among studies, the most common design was retrospective, populations varied, control groups were not consistently used, follow-up was primarily short, and sample sizes were small. One study evaluated pharmacist-driven CGM in a community pharmacy setting. Ten studies took place in the ambulatory care setting. Barriers to initiating pharmacist-driven CGM as a clinical service include educational, logistical, workflow, and financial incentive. Beneficial outcomes from pharmacist-driven CGM include improved quality of life, increased empowerment, and improved glycemic control. CONCLUSION: There is lack of strong evidence to support pharmacist-driven CGM in the community pharmacy setting. However, small studies suggest pharmacist-driven CGM is feasible and beneficial in the ambulatory care setting. Further exploration of how educational, logistical, workflow, and financial barriers can be overcome is warranted, given potential for improved clinical outcomes.

Intrinsic brain connectivity alterations despite intact pain inhibition in subjects with neuropathic pain after spinal cord injury: a pilot study.

Endogenous pain modulation in humans is frequently investigated with conditioned pain modulation (CPM). Deficient pain inhibition is a proposed mechanism that contributes to neuropathic pain (NP) after spinal cord injury (SCI). Recent studies have combined CPM testing and neuroimaging to reveal neural correlates of CPM efficiency in chronic pain. This study investigated differences in CPM efficiency in relation to resting-state functional connectivity (rsFC) between 12 SCI-NP subjects and 13 age- and sex-matched healthy controls (HC). Twelve and 11 SCI-NP subjects were included in psychophysical and rsFC analyses, respectively. All HC were included in the final analyses. Psychophysical readouts were analysed to determine CPM efficiency within and between cohorts. Group differences of rsFC, in relation to CPM efficiency, were explored with seed-to-voxel rsFC analyses with pain modulatory regions, e.g. ventrolateral periaqueductal gray (vlPAG) and amygdala. Overall, pain inhibition was not deficient in SCI-NP subjects and was greater in those with more intense NP. Greater pain inhibition was associated with weaker rsFC between the vlPAG and amygdala with the visual and frontal cortex, respectively, in SCI-NP subjects but with stronger rsFC in HC. Taken together, SCI-NP subjects present with intact pain inhibition, but can be differentiated from HC by an inverse relationship between CPM efficiency and intrinsic connectivity of supraspinal regions. Future studies with larger cohorts are necessary to consolidate the findings in this study.

Quantitative determination of SLC2A1 variant functional effects in GLUT1 deficiency syndrome.

OBJECTIVE: The goal of this study is to demonstrate the utility of a growth assay to quantify the functional impact of single nucleotide variants (SNVs) in SLC2A1, the gene responsible for Glut1DS. METHODS: The functional impact of 40 SNVs in SLC2A1 was quantitatively determined in HAP1 cells in which SLC2A1 is required for growth. Donor libraries were introduced into the endogenous SLC2A1 gene in HAP1-Lig4KO cells using CRISPR/Cas9. Cell populations were harvested and sequenced to quantify the effect of variants on growth and generate a functional score. Quantitative functional scores were compared to 3-OMG uptake, SLC2A1 cell surface expression, CADD score, and clinical data, including CSF/blood glucose ratio. RESULTS: Nonsense variants (N = 3) were reduced in cell culture over time resulting in negative scores (mean score: -1.15 ± 0.17), whereas synonymous variants (N = 10) were not depleted (mean score: 0.25 ± 0.12) (P < 2e-16). Missense variants (N = 27) yielded a range of functional scores including slightly negative scores, supporting a partial function and intermediate phenotype. Several variants with normal results on either cell surface expression (p.N34S and p.W65R) or 3-OMG uptake (p.W65R) had negative functional scores. There is a moderate but significant correlation between our functional scores and CADD scores. INTERPRETATION: Cell growth is useful to quantitatively determine the functional effects of SLC2A1 variants. Nonsense variants were reliably distinguished from benign variants in this in vitro functional assay. For facilitating early diagnosis and therapeutic intervention, future work is needed to determine the functional effect of every possible variant in SLC2A1.

Real-time evaluation of a hydrogel delivery vehicle for cancer immunotherapeutics within embedded spheroid cultures.

Many protein immunotherapeutics are hindered by transport barriers that prevent the obtainment of minimum effective concentrations (MECs) in solid tumors. Local delivery vehicles with tunable release (infusion) rates for immunotherapeutics are being developed to achieve local and sustained release. To expedite their discovery and translation, in vitro models can identify promising delivery vehicles and immunotherapies that benefit from sustained release by evaluating cancer spheroid killing in real-time. Using displacement affinity release (DAR) within a hydrogel, we tuned the release of a CD133 targeting dual antigen T cell engager (DATE) without the need for further DATE or hydrogel modifications, yielding an injectable vehicle that acts as a tunable infusion pump. To quantify bioactivity benefits, a 3D embedded cancer spheroid model was developed for the evaluation of sustained protein release and combination therapies on T cell mediated spheroid killing. Using automated brightfield and fluorescent microscopy, the size of red fluorescent protein (iRFP670) expressing spheroids were tracked to quantify spheroid growth or killing over time as a function of controlled delivery. We demonstrate that sustained DATE release enhanced T cell mediated killing of embedded glioblastoma spheroids at longer timepoints, killing was further enhanced with the addition of anti-PD1 antibody (αPD1). The multi-cellular embedded spheroid model with automated microscopy demonstrated the benefit of extended bispecific release on T cell mediated killing, which will expedite the identification and translation of delivery vehicles such as DAR for immunotherapeutics.

Descending pain modulatory efficiency in healthy subjects is related to structure and resting connectivity of brain regions.

The descending pain modulatory system in humans is commonly investigated using conditioned pain modulation (CPM). Whilst variability in CPM efficiency, i.e., inhibition and facilitation, is normal in healthy subjects, exploring the inter-relationship between brain structure, resting-state functional connectivity (rsFC) and CPM readouts will provide greater insight into the underlying CPM efficiency seen in healthy individuals. Thus, this study combined CPM testing, voxel-based morphometry (VBM) and rsFC to identify the neural correlates of CPM in a cohort of healthy subjects (n =40), displaying pain inhibition (n = 29), facilitation (n = 10) and no CPM effect (n = 1). Clusters identified in the VBM analysis were implemented in the rsFC analysis alongside key constituents of the endogenous pain modulatory system. Greater pain inhibition was related to higher volume of left frontal cortices and stronger rsFC between the motor cortex and periaqueductal grey. Conversely, weaker pain inhibition was related to higher volume of the right frontal cortex - coupled with stronger rsFC to the primary somatosensory cortex, and rsFC between the amygdala and posterior insula. Overall, healthy subjects showed higher volume and stronger rsFC of brain regions involved with descending modulation, while the lateral and medial pain systems were related to greater pain inhibition and facilitation during CPM, respectively. These findings reveal structural alignments and functional interactions between supraspinal areas involved in CPM efficiency. Ultimately understanding these underlying variations and how they may become affected in chronic pain conditions, will advance a more targeted subgrouping in pain patients for future cross-sectional studies investigating endogenous pain modulation.

Graft-Then-Shrink: Simultaneous Generation of Antifouling Polymeric Interfaces and Localized Surface Plasmon Resonance Biosensors.

Antifouling polymer coatings that are simple to manufacture are crucial for the performance of medical devices such as biosensors. "Grafting-to", a simple technique where presynthesized polymers are immobilized onto surfaces, is commonly employed but suffers from nonideal polymer packing leading to increased biofouling. Herein, we present a material prepared via the grafting-to method with improved antifouling surface properties and intrinsic localized surface plasmon resonance (LSPR) sensor capabilities. A new substrate shrinking fabrication method, Graft-then-Shrink, improved the antifouling properties of polymer-coated Au surfaces by altering graft-to polymer packing while simultaneously generating wrinkled Au structures for LSPR biosensing. Thiol-terminated, antifouling, hydrophilic polymers were grafted to Au-coated prestressed polystyrene (PS) followed by shrinking upon heating above the PS glass transition temperature. Interestingly, the polymer molecular weight and hydration influenced Au wrinkling patterns. Compared to Shrink-then-Graft controls, where polymers are immobilized post shrinking, Graft-then-Shrink increased the polymer content by 76% in defined footprints and improved the antifouling properties as demonstrated by 84 and 72% reduction in macrophage adhesion and protein adsorption, respectively. Wrinkled Au LSPR sensors had sensitivities of ∼200-1000 Δλ/ΔRIU, comparing favorably to commercial LSPR sensors, and detected biotin-avidin and desthiobiotin-avidin complexation in a concentration-dependent manner using a standard plate reader and a 96-well format.

Modulating the Thermoresponse of Polymer-Protein Conjugates with Hydrogels for Controlled Release.

Sustained release is being explored to increase plasma and tissue residence times of polymer-protein therapeutics for improved efficacy. Recently, poly(oligo(ethylene glycol) methyl ether methacrylate) (PEGMA) polymers have been established as potential PEG alternatives to further decrease immunogenicity and introduce responsive or sieving properties. We developed a drug delivery system that locally depresses the lower critical solution temperature (LCST) of PEGMA-protein conjugates within zwitterionic hydrogels for controlled release. Inside the hydrogel the conjugates partially aggregate through PEGMA-PEGMA chain interactions to limit their release rates, whereas conjugates outside of the hydrogel are completely solubilized. Release can therefore be tuned by altering hydrogel components and the PEGMA's temperature sensitivity without the need for traditional controlled release mechanisms such as particle encapsulation or affinity interactions. Combining local LCST depression technology and degradable zwitterionic hydrogels, complete release of the conjugate was achieved over 13 days.

Supraspinal nociceptive networks in neuropathic pain after spinal cord injury.

Neuropathic pain following spinal cord injury involves plastic changes along the whole neuroaxis. Current neuroimaging studies have identified grey matter volume (GMV) and resting-state functional connectivity changes of pain processing regions related to neuropathic pain intensity in spinal cord injury subjects. However, the relationship between the underlying neural processes and pain extent, a complementary characteristic of neuropathic pain, is unknown. We therefore aimed to reveal the neural markers of widespread neuropathic pain in spinal cord injury subjects and hypothesized that those with greater pain extent will show higher GMV and stronger connectivity within pain related regions. Thus, 29 chronic paraplegic subjects and 25 healthy controls underwent clinical and electrophysiological examinations combined with neuroimaging. Paraplegics were demarcated based on neuropathic pain and were thoroughly matched demographically. Our findings indicate that (a) spinal cord injury subjects with neuropathic pain display stronger connectivity between prefrontal cortices and regions involved with sensory integration and multimodal processing, (b) greater neuropathic pain extent, is associated with stronger connectivity between the posterior insular cortex and thalamic sub-regions which partake in the lateral pain system and (c) greater intensity of neuropathic pain is related to stronger connectivity of regions involved with multimodal integration and the affective-motivational component of pain. Overall, this study provides neuroimaging evidence that the pain phenotype of spinal cord injury subjects is related to the underlying function of their resting brain.

Investigation of Cerebral White Matter Changes After Spinal Cord Injury With a Measure of Fiber Density.

Remote neurodegenerative changes in supraspinal white matter (WM) can manifest after central lesions such as spinal cord injury (SCI). The majority of diffusion tensor imaging (DTI) studies use traditional metrics such as fractional anisotropy (FA) and mean diffusivity (MD) to investigate microstructural changes in cerebral WM after SCI. However, interpretation of FA readouts is often challenged by inherent limitations of the tensor model. Recent developments in novel diffusion markers, such as fiber density (FD), allows more accurate depictions of WM pathways and has shown more reliable quantification of WM alterations compared to FA in recent studies of neurological diseases. This study investigated if FD provides useful characterization of supraspinal WM integrity after SCI in addition to the traditional DTI readouts. FA, MD, and FD maps were derived from diffusion datasets of 20 patients with chronic SCI and compared with 19 healthy controls (HC). Group differences were investigated across whole brain WM using tract-based spatial statistics and averaged diffusion values of the corticospinal tract (CST) and thalamic radiation (TR) were extracted for comparisons between HC and SCI subgroups. We also related diffusion readouts of the CST and TR with clinical scores of sensorimotor function. To investigate which diffusion markers of the CST and TR delineate HC and patients with SCI a receiver operating characteristic (ROC) analysis was performed. Overall, patients with an SCI showed decreased FA of the TR and CST. ROC analysis differentiated HC and SCI based on diffusion markers of large WM tracts including FD of the TR. Furthermore, patients' motor function was positively correlated with greater microstructural integrity of the CST. While FD showed the strongest correlation, motor function was also associated with FA and MD of the CST. In summary, microstructural changes of supraspinal WM in patients with SCI can be detected using FD as a complementary marker to traditional DTI readouts and correlates with their clinical characteristics. Future DTI studies may benefit from utilizing this novel marker to investigate complex large WM tracts in patient cohorts with varying presentations of SCI or neurodegenerative diseases.

Synthesis of di- and triacrylamides with tertiary amine cores and their evaluation as monomers in dental adhesive interfaces.

PURPOSE/AIM: In an attempt to increase the service life of dental adhesive interfaces, more hydrolytically and enzymatically-stable methacrylate alternatives, such as methacrylamides, have been proposed. The aim of this study was to investigate polymerization behavior, as well as mechanical and biological properties of experimental adhesives containing multi-functional acrylamides. MATERIALS AND METHODS: Multi-functional acrylamides (N,N-Bis[(3-methylaminoacryl)propyl]methylamine - BMAAPMA, Tris[(2-methylaminoacryl)ethyl]amine - TMAAEA, N,N'-bis(acrylamido) 1,4-diazepane - BAADA, N,N-Diethyl-1,3-bis(acrylamido)propane - DEBAAP) or HEMA (2-Hydroxyethyl methacrylate - control) were added at 40 wt% to UDMA. 0.2 wt% DMPA and 0.4 wt% DPI-PF6 were used as initiators. Polymerization kinetics was followed in real-time in near-IR during photoactivation (320-500 nm, at 630 mW/cm2). Water sorption/solubility and flexural strength/modulus were measured according to ISO 4049. 1H NMR was used to assess monomer degradation kinetics. MTT assay was used to assess cytotoxicity against OD-21 and DPSC cells. Biofilm formation and adhesion were assessed by Luciferase Assay and Impingement technique, respectively. Solvated adhesives (40 vol% ethanol) were used to test interfacial adhesion strength. The results were analyzed by ANOVA/Tukey's test (α = 0.05). RESULTS: In general, the pure methacrylate mixture had higher rate of polymerization (Rpmax), degree of conversion (DC) at Rpmax, and final DC than the acrylamides. Flexural properties after water storage decreased between 11 and 65%, more markedly for acrylamides. Interfacial bond strength was greater and more stable long-term for the newly synthesized acrylamide formulations (less than 4% reduction at 6 months) compared to the methacrylate experimental control (42% reduction at 6 months). HEMA degraded by almost 90%, while the acrylamides showed no degradation in acidic conditions. Cytotoxicity and biofilm formation, in general, were similar for all groups. CONCLUSIONS: Despite demonstrating high water sorption, the acrylamide-containing materials had similar mechanical and biological properties and enhanced interfacial bond strength stability compared to the methacrylate control.

Alternative monomer for BisGMA-free resin composites formulations.

OBJECTIVE: Water sorption, high volumetric shrinkage, polymerization stress, and potential estrogenic effects triggered by leached compounds are some of the major concerns related to BisGMA-TEGDMA co-monomer systems used in dental composites. These deficiencies call for the development of alternative organic matrices in order to maximize the clinical lifespan of resin composite dental restorations. This study proposes BisGMA-free systems based on the combination of UDMA and a newly synthesized diurethane dimethacrylate, and evaluates key mechanical and physical properties of the resulting materials. METHODS: 2EMATE-BDI (2-hydroxy-1-ethyl methacrylate) was synthesized by the reaction between 2-hydroxy-1-ethyl methacrylate with a difunctional isocyanate (1.3-bis (1- isocyanato-1-methylethylbenzene) - BDI). The compound was copolymerized with UDMA (urethane dimethacrylate) at 40 and 60wt%. UDMA copolymerizations with 40 and 60wt% TEGDMA (triethylene glycol dimethacrylate) were tested as controls, as well as a formulation based in BisGMA (bisphenol A-glycidyl methacrylate)-TEGDMA 60:40% (BT). The organic matrices were made polymerizable by the addition of DMPA (2.2-dimethoxyphenoxy acetophenone) and DPI-PF6 (diphenyliodonium hexafluorophosphate) at 0.2 and 0.4wt%, respectively. Formulations were tested as composite with the addition of 70wt% inorganic content consisting of barium borosilicate glass (0.7µm) and fumed silica mixed in 95 and 5wt%, respectively. All photocuring procedures were carried out by a mercury arc lamp filtered to 320-500nm at 800mW/cm2. The experimental resin composites were tested for kinetics of polymerization and polymerization stress in real time. Flexural strength, elastic modulus, water sorption, and solubility were assessed according to ISO 4049. Biofilm formation was analyzed after 24h by luciferase assay. Data were statistically analyzed by one-way ANOVA and Tukey's test (α≤0.05). RESULTS: In general, the addition of 2EMATE-BDI into the formulations decreased the maximum rate of polymerization (RPMAX), the degree of conversion at RPMAX (DC at RPMAX), and the final degree of conversion (final DC). However, these reductions did not compromise mechanical properties, which were comparable to the BT controls, especially after 7-day water incubation. The incorporation of 60wt% 2EMATE-BDI reduced water sorption of the composite. 2EMATE-BDI containing formulations showed reduction in polymerization stress of 30% and 50% in comparison to BT control and TEGDMA copolymerizations, respectively. Biofilm formation was similar among the tested groups. SIGNIFICANCE: The use of the newly synthesized diurethane dimethacrylate as co-monomer in dental resin composite formulations seems to be a promising option to develop polymers with low-shrinkage and potentially decreased water degradation.

Molecular Mechanism for the Suppression of Alpha Synuclein Membrane Toxicity by an Unconventional Extracellular Chaperone.

Alpha synuclein (αS) oligomers are a key component of Lewy bodies implicated in Parkinson's disease (PD). Although primarily intracellular, extracellular αS exocytosed from neurons also contributes to PD pathogenesis through a prion-like transmission mechanism. Here, we show at progressive degrees of resolution that the most abundantly expressed extracellular protein, human serum albumin (HSA), inhibits αS oligomer (αSn) toxicity through a three-pronged mechanism. First, endogenous HSA targets αSn with sub-µM affinity via solvent-exposed hydrophobic sites, breaking the catalytic cycle that promotes αS self-association. Second, HSA remodels αS oligomers and high-MW fibrils into chimeric intermediates with reduced toxicity. Third, HSA unexpectedly suppresses membrane interactions with the N-terminal and central αS regions. Overall, our findings suggest that the extracellular proteostasis network may regulate αS cell-to-cell transmission not only by reducing the populations of membrane-binding competent αS oligomers but possibly also by shielding the membrane interface from residual toxic species.

Fabrication of low-fouling, high-loading polymeric surfaces through pH-controlled RAFT.

Low-fouling and high-loading surfaces are increasingly important for biosensing and blood purification technologies. Selective and efficient target binding from complex media can be achieved with poly(carboxybetaine) (pCB) surfaces that consist of a dense brush layer to resist non-specific protein adsorption and a sparse "mushroom" upper layer for high-density capture agent immobilization (i.e. high-loading). We developed pH-controlled surface-reversible addition-fragmentation chain-transfer (S-RAFT) polymerization to simplify fabrication of multi-modal, low-fouling and high-loading pCB surfaces without the need for quenching or re-initiation steps, toxic transition metals or light irradiation. Multi-modal polymer layers were produced through partial polymer termination by temporarily raising the pH to aminolyse a fraction of dormant chain transfer agents (CTAs); remaining polymer chains with intact CTAs continued uninterrupted extension to create the "mushroom" upper layer. The multi-modal pCB surfaces were low-fouling towards proteins (<6.7 ng cm-2), and macrophages. Compared to mono-modal brush surfaces, multi-modal pCB surfaces were high-loading with 5-fold greater capture agent immobilization (e.g. antibody) and 4-fold greater target binding (e.g. biotin-fluorescein).

Antibacterial, ester-free monomers: Polymerization kinetics, mechanical properties, biocompatibility and anti-biofilm activity.

OBJECTIVES: Quaternary ammonium (QA) methacrylate monomers have been extensively investigated and demonstrate excellent antibacterial properties. However, the presence of ester bonds makes them prone to degradation in the oral cavity. In this study, ester-free QA monomers based on meth-acrylamides were synthesized and screened for polymerization kinetics, mechanical properties and antibacterial effects. MATERIALS AND METHODS: Tertiary quaternary ammonium acrylamides (AM) and methacrylamides (MAM) with alkyl side chain lengths of 9 and 14 carbons (C9 and C14) were synthesized and incorporated at 10 wt% into experimental composites based on BisGMA:TEGDMA (1:1), camphorquinone/ethyl-4-dimethylaminobenzoate (0.2/0.8 wt%) and 70 wt% barium glass fillers. Analogous methacrylate versions (MA) were used as controls. Degree of conversion (DC) and rate of polymerization (RP) during photoactivation (800 mW/cm2) were followed in real-time with near-IR. Flexural Strength (FS) and Modulus (E) were measured on 2 × 2 × 25 mm bars in 3-point bending after 24 h dry storage and 7-day storage in water at 37 °C. Antimicrobial properties and biofilm adhesion (fouling) were evaluated by bioluminescence (Luciferase Assay) and biofilm removal by water spray microjet impingement test, respectively. Cytotoxicity was assessed by MTT assay on dental pulp stem cells (DPSC). Data were analyzed with one-way ANOVA/Tukey's test (α = 0.05). RESULTS: DC was similar for all groups tested (∼70%). Both MAMs and C14-AM presented significantly lower RP. Under dry conditions, FS (110-120 MPa) and E (8-9 GPa) were similar for all groups. After water storage, all materials presented FS/E similar to the control, except for C14-AM (for FS) and C14-MAM (for E), which were lower. All C14 versions were strongly antibacterial, decreasing the titer counts of biofilm by more than two orders of magnitude in comparison to the control. C9 monomers did not present significant antibacterial nor antifouling properties. And biofilms had approximately equivalent adhesion on the C9 composites as on the control. Cytotoxicity did not show significant differences between the MA and AM versions and the control group. CONCLUSIONS: C14-QA monomers based on methacrylates and meth-acrylamides present strong antibacterial properties, and in general, similar conversion/mechanical properties compared to the methacrylate control. STATEMENT OF SIGNIFICANCE: This work demonstrates the viability of methacrylamides and acrylamides as potential components in dental restorative materials with antimicrobial properties. The use of ester-free polymerizable functionalities has the potential of improving the degradation resistance of these materials long-term. The use of (meth)acrylamides did not interfere with the antimicrobial potential of quaternary ammonium-based materials.

Displacement Affinity Release of Antibodies from Injectable Hydrogels.

Current methods to tune release rates of therapeutic antibodies (Abs) for local delivery are complex and routinely require bioconjugations that may reduce Ab bioactivity. To rapidly tune release profiles of bioactive Abs, we developed a biophysical interaction system within a neutravidin modified poly(carboxybetaine) hydrogel (pCB-NT) that tunes release rates of desthiobiotinylated Abs (D-Abs) using a constant hydrogel and D-Ab combination. Herein, we delivered desthiobiotinylated bevacizumab (D-Bv), a recombinant humanized monoclonal IgG1 Ab for antiangiogenic cancer therapies. D-Bv's high affinity for pCB-NT (KD 7.8 × 10-10 M; t1/2 ∼ 2 h) produces a slow D-Bv release rate (∼5 ng day-1) that is increased by the dissolution of hydrogel encapsulated biotin derivative pellets, which displaces D-Bv from pCB-NT binding sites. In contrast to traditional affinity systems, displacement affinity release of Abs (DARA) does not require Ab or hydrogel modifications for each unique release rate. D-Bv release rates were tuned by simply altering the total biotin derivative concentration; the effective first-order (keff) and mass per day release rates were tuned 25- and 8-fold, respectively. Local surface plasmon resonance (LSPR) and biolayer interferometry (BLI) confirmed the D-Bv binding affinity for the corresponding ligand and Fc receptor, demonstrating that the biophysical interaction system is amenable to anticancer Abs for receptor or cytokine blockade and immune cell recruitment to cancer cells.

Atomic resolution map of the soluble amyloid beta assembly toxic surfaces.

Soluble amyloid beta assemblies (Aß n ) are neurotoxic and play a central role in the early phases of the pathogenesis cascade leading to Alzheimer's disease. However, the current knowledge about the molecular determinants of Aß n toxicity is at best scant. Here, we comparatively analyze Aß n prepared in the absence or presence of a catechin library that modulates cellular toxicity. By combining solution NMR with dynamic light scattering, fluorescence spectroscopy, electron microscopy, wide-angle X-ray diffraction and cell viability assays, we identify a cluster of unique molecular signatures that distinguish toxic vs. nontoxic Aß assemblies. These include the exposure of a hydrophobic surface spanning residues 17-28 and the concurrent shielding of the highly charged N-terminus. We show that the combination of these two dichotomous structural transitions promotes the colocalization and insertion of ß-sheet rich Aß n into the membrane, compromising membrane integrity. These previously elusive toxic surfaces mapped here provide an unprecedented foundation to establish structure-toxicity relationships of Aß assemblies.

Aptamers in Education: Undergraduates Make Aptamers and Acquire 21st Century Skills Along the Way.

Aptamers have a well-earned place in therapeutic, diagnostic, and sensor applications, and we now show that they provide an excellent foundation for education, as well. Within the context of the Freshman Research Initiative (FRI) at The University of Texas at Austin, students have used aptamer selection and development technologies in a teaching laboratory to build technical and 21st century skills appropriate for research scientists. One of the unique aspects of this course-based undergraduate research experience is that students develop and execute their own projects, taking ownership of their experience in what would otherwise be a traditional teaching lab setting. Of the many successes, this work includes the isolation and characterization of novel calf intestinal alkaline phosphatase (anti-CIAP) RNA aptamers by an undergraduate researcher. Further, preliminary survey data suggest that students who participate in the aptamer research experience express significant gains in their self-efficacy to conduct research, and their perceived ability to communicate scientific results, as well as organize and interpret data. This work describes, for the first time, the use of aptamers in an educational setting, highlights the positive student outcomes of the aptamer research experience, and presents the research findings relative to the novel anti-CIAP aptamer.

Tunable degradation of low-fouling carboxybetaine-hyaluronic acid hydrogels for applications in cell encapsulation.

Low-fouling hydrogels with tunable degradation rates and biochemical environments have the potential to improve adoptive cell therapies for cancer immunotherapy and regenerative medicine. To this end, we developed in situ gelling hydrogels from low-fouling poly(carboxybetaine-co-maleimide) (pCBM) random copolymers and thiolated hyaluronic acid (HA-SH). pCBM-HA hydrogel enzymatic degradation rates were tuned 5 fold by altering pCBM composition (4, 11, and 16 maleimide mol%) and 2.3 fold by HA-SH concentration (1-2 wt%). pCBM-HA gels were low-fouling towards bovine serum albumin (BSA; adsorbed ∼20 µg cm-2) and resisted fibroblast adhesion. To control pCBM-HA bioactivity, the cell adhesive peptide CGRGDS was immobilized on pCBM to promote fibroblast adhesion (39% decrease in circularity), which increased metabolic activity by ∼50%. pCBM-HA modified with CGRGDS enhanced the metabolic activity of encapsulated T cells by ∼21% compared to gels without HA, indicating their potential for immunotherapies. Low-fouling pCBM-HA hydrogels provide a vehicle with tunable degradation rates and biochemical environments for encapsulation applications in cell adoptive therapies.

Improved Efficacy of Antibody Cancer Immunotherapeutics through Local and Sustained Delivery.

Antibodies are a growing class of cancer immunotherapeutics that facilitate immune-cell-mediated killing of tumors. However, the efficacy and safety of immunotherapeutics are limited by transport barriers and poor tumor uptake, which lead to high systemic concentrations and potentially fatal side effects. To increase tumor antibody immunotherapeutic concentrations while decreasing systemic concentrations, local delivery vehicles for sustained antibody release are being developed. The focus of this review is to define the material properties required for implantable controlled antibody delivery and highlight the controlled-release strategies that are applicable to antibody immunotherapeutics.