Vectorcardiography Predicts Heart Failure in Patients Following ST Elevation Myocardial Infarction.

BACKGROUND: Modeling outcomes, such as onset of heart failure (HF) or mortality, in patients following ST elevation myocardial infarction (STEMI) is challenging but clinically very useful. The acute insult following a myocardial infarction and chronic degeneration seen in HF involve a similar process where a loss of cardiomyocytes and abnormal remodeling lead to pump failure. This process may alter the strength and direction of the heart's net depolarization signal. We hypothesize that changes over time in unique parameters extracted using vectorcardiography (VCG) have the potential to predict outcomes in patients post-STEMI and could eventually be used as a noninvasive and cost-effective surveillance tool for characterizing the severity and progression of HF to guide evidence-based therapies. METHODS: We identified 162 patients discharged from Michigan Medicine between 2016 and 2021 with a diagnosis of acute STEMI. For each patient, a single 12-lead ECG > 1 week pre-STEMI and > 1 week post-STEMI were collected. A set of unique VCG parameters were derived by analyzing features of the QRS complex. We used LASSO regression analysis incorporating clinical variables and VCG parameters to create a predictive model for HF, mortality, or the composite at 90, 180, and 365 days post-STEMI. RESULTS: The VCG model is most predictive for HF onset at 90 days with a robust AUC. Variables from the HF model mitigating or driving risk, at a p < 0.05, were primarily parameters that assess the area swept by the depolarization vector including the 3D integral and convex hull in select spatial octants and quadrants.

Simulation-guided tunable DNA probe design for mismatch tolerant hybridization.

The ability to both sensitively and specifically assess the sequence composition of a nucleic acid strand is an ever-growing field. Designing a detection scheme that can perform this function when the sequence of the target being detected deviates significantly from the canonical sequence however is difficult in part because probe/primer design is based on established Watson-Crick base-pairing rules. We present here a robust and tunable toehold-based exchange probe that can detect a sequence with a variable number of SNPs of unknown identity by inserting a series of controlled, sequential mismatches into the protector seal of the toehold probe, in an effort to make the protector seal "sloppy". We show that the mismatch-tolerant system follows predicted behavior closely even with targets containing up to four mismatches that thermodynamically deviate from the canonical sequence by up to 15 kcal/mole. The system also performs faithfully regardless of the global mismatch position on either the protector seal or target. Lastly, we demonstrate the generalizability of the approach by testing the increasingly mismatch-tolerant protectors on HIV clinical samples to show that the system is capable of resolving multiple, iteratively mutated sequences derived from numerous HIV sub-populations with remarkable precision.

Development of a Novel Class of Self-Assembling dsRNA Cancer Therapeutics: A Proof-of-Concept Investigation.

Cancer has proven to be an extremely difficult challenge to treat. Several fundamental issues currently underlie cancer treatment, including differentiating self from nonself, functional coupling of the recognition and therapeutic components of various therapies, and the propensity of cancerous cells to develop resistance to common treatment modalities via evolutionary pressure. Given these limitations, there is an increasing need to develop an all-encompassing therapeutic that can uniquely target malignant cells, decouple recognition from treatment, and overcome evolutionarily driven cancer resistance. We describe herein a new class of programmable self-assembling double-stranded RNA (dsRNA)-based cancer therapeutics that uniquely targets aberrant genetic sequences and in a functionally decoupled manner, undergoes oncogenic RNA-activated displacement (ORAD), initiating a therapeutic cascade that induces apoptosis and immune activation. As a proof of concept, we show that RNA strands targeting the EWS/Fli1 fusion gene in Ewing sarcoma cells that are end blocked with phosphorothioate bonds and additionally sealed with a 2'-deoxyuridine (2'-U)-modified DNA protector can be used to induce specific and potent killing of cells containing the target oncogenic sequence but not wild type.

Metallic Nanoparticles for Cancer Immunotherapy.

Cancer immunotherapy, or the utilization of the body's immune system to attack tumor cells, has gained prominence over the past few decades as a viable cancer treatment strategy. Recently approved immunotherapeutics have conferred remission upon patients with previously bleak outcomes and have expanded the number of tools available to treat cancer. Nanoparticles -including polymeric, liposomal, and metallic formulations - naturally traffic to the spleen and lymph organs and the relevant immune cells therein, making them good candidates for delivery of immunotherapeutic agents. Metallic nanoparticle formulations in particular are advantageous because of their potential for dense surface functionalization and their capability for optical or heat based therapeutic methods. Many research groups have investigated the potential of nanoparticle-mediated delivery platforms to improve the efficacy of immunotherapies. Despite the significant preclinical successes demonstrated by many of these platforms over the last twenty years, few metallic nanoparticles have successfully entered clinical trials with none achieving FDA approval for cancer therapy. In this review, we will discuss preclinical research and clinical trials involving metallic nanoparticles (MNPs) for cancer immunotherapy applications and discuss the potential for clinical translation of MNPs.

An inexpensive, customizable microscopy system for the automated quantification and characterization of multiple adherent cell types.

Cell quantification assays are essential components of most biological and clinical labs. However, many currently available quantification assays, including flow cytometry and commercial cell counting systems, suffer from unique drawbacks that limit their overall efficacy. In order to address the shortcomings of traditional quantification assays, we have designed a robust, low-cost, automated microscopy-based cytometer that quantifies individual cells in a multiwell plate using tools readily available in most labs. Plating and subsequent quantification of various dilution series using the automated microscopy-based cytometer demonstrates the single-cell sensitivity, near-perfect R2 accuracy, and greater than 5-log dynamic range of our system. Further, the microscopy-based cytometer is capable of obtaining absolute counts of multiple cell types in one well as part of a co-culture setup. To demonstrate this ability, we recreated an experiment that assesses the tumoricidal properties of primed macrophages on co-cultured tumor cells as a proof-of-principle test. The results of the experiment reveal that primed macrophages display enhanced cytotoxicity toward tumor cells while simultaneously losing the ability to proliferate, an example of a dynamic interplay between two cell populations that our microscopy-based cytometer is successfully able to elucidate.

Heart failure education in the emergency department markedly reduces readmissions in un- and under-insured patients.

BACKGROUND: Heart failure (HF) readmissions are a longstanding national healthcare issue for both hospitals and patients. Our purpose was to evaluate the efficacy of a structured, educational intervention targeted towards un- and under-insured emergency department (ED) HF patients. METHODS: HF patients presenting to the ED for care were enrolled between July and December 2015 as part of an open label, interventional study, using a parallel observational control group. Eligible patients provided informed consent, had an established HF diagnosis, and were hemodynamically stable. Intervention patients received a standardized educational intervention in the ED waiting room before seeing the emergency physician, and a 30-day telephone follow-up. Primary and secondary endpoints were 30- and 90-day ED and hospital readmission rates, as well as days alive and out of hospital (DAOH) respectively. RESULTS: Of the 94 patients enrolled, median age was 58.4 years; 40.4% were female, and 54.3% were African American. Intervention patients (n = 45) experienced a 47.8% and 45.3% decrease in ED revisits (P = 0.02 &P < 0.001), and 60.0% and 47.4% decrease in hospital readmissions (P = 0.049 &P = 0.007) in the 30 and 90 days pre- versus post-intervention respectively. Control patients (n = 49) had no change in hospital readmissions or 30-day ED revisits, but experienced a 36.6% increase in 90-day ED revisits (P = 0.03). Intervention patients also saw a 59.2% improvement in DAOH versus control patients (P = 0.03). CONCLUSION: An ED educational intervention markedly decreases ED and hospital readmissions in un- and under-insured HF patients.

A mechanistic investigation exploring the differential transfection efficiencies between the easy-to-transfect SK-BR3 and difficult-to-transfect CT26 cell lines.

BACKGROUND: Gold-polyamidoamine (AuPAMAM) has previously been shown to successfully transfect cells with high efficiency. However, we have observed that certain cell types are more amenable to Au-PAMAM transfection than others. Here we utilized two representative cell lines-a "difficult to transfect" CT26 cell line and an "easy to transfect" SK-BR3 cell line-and attempted to determine the underlying mechanism for differential transfection in both cell types. Using a commonly established poly-cationic polymer similar to PAMAM (polyethyleneimine, or PEI), we additionally sought to quantify the relative transfection efficiencies of each vector in CT26 and SK-BR3 cells, in the hopes of elucidating any mechanistic differences that may exist between the two transfection vectors. RESULTS: A comparative time course analysis of green fluorescent protein reporter-gene expression and DNA uptake was conducted to quantitatively compare PEI- and AuPAMAM-mediated transfection in CT26 and SK-BR3, while flow cytometry and confocal microscopy were used to determine the contribution of cellular uptake, endosomal escape, and cytoplasmic transport to the overall gene delivery process. Results from the time course analysis and flow cytometry studies revealed that initial complex uptake and cytoplasmic trafficking to the nucleus are likely the two main factors limiting CT26 transfectability. CONCLUSIONS: The cell type-dependent uptake and intracellular transport mechanisms impacting gene therapy remain largely unexplored and present a major hurdle in the application-specific design and efficiency of gene delivery vectors. This systematic investigation offers insights into the intracellular mechanistic processes that may account for cell-to-cell differences, as well as vector-to-vector differences, in gene transfectability.

Changes in Optical Properties of Plasmonic Nanoparticles in Cellular Environments are Modulated by Nanoparticle PEGylation and Serum Conditions.

When plasmonic nanoparticles (NPs) are internalized by cells and agglomerate within intracellular vesicles, their optical spectra can shift and broaden as a result of plasmonic coupling of NPs in close proximity to one another. For such optical changes to be accounted for in the design of plasmonic NPs for light-based biomedical applications, quantitative design relationships between designable factors and spectral shifts need to be established. Here we begin building such a framework by investigating how functionalization of gold NPs (AuNPs) with biocompatible poly(ethylene) glycol (PEG), and the serum conditions in which the NPs are introduced to cells impact the optical changes exhibited by NPs in a cellular context. Utilizing darkfield hyperspectral imaging, we find that PEGylation decreases the spectral shifting and spectral broadening experienced by 100 nm AuNPs following uptake by Sk-Br-3 cells, but up to a 33 ± 12 nm shift in the spectral peak wavelength can still occur. The serum protein-containing biological medium also modulates the spectral changes experienced by cell-exposed NPs through the formation of a protein corona on the surface of NPs that mediates NP interactions with cells: PEGylated AuNPs exposed to cells in serum-free conditions experience greater spectral shifts than in serum-containing environments. Moreover, increased concentrations of serum (10, 25, or 50 %) result in the formation of smaller intracellular NP clusters and correspondingly reduced spectral shifts after 5 and 10 h NP-cell exposure. However, after 24 h, NP cluster size and spectral shifts are comparable and become independent of serum concentration. By elucidating the impact of PEGylation and serum concentration on the spectral changes experienced by plasmonic NPs in cells, this study provides a foundation for the optical engineering of plasmonic NPs for use in biomedical environments.

Impaired restoration of plasmacytoid dendritic cells in HIV-1-infected patients with poor CD4 T cell reconstitution is associated with decrease in capacity to produce IFN-alpha but not proinflammatory cytokines.

We analyzed reconstitution characteristics of plasmacytoid dendritic cells (PDCs) and myeloid DCs-1 in 38 HIV-1-infected patients with impaired restoration of CD4 T cell counts despite prolonged suppression of plasma viremia (discordant) and compared them with 42 patients showing good immunological and virological responses following highly active antiretroviral therapy (HAART). While myeloid DCs showed spontaneous recovery following HAART in both the groups, the discordant patients demonstrated poor peripheral reconstitution of PDCs as compared with concordant patients. The ability of PDCs to produce IFN-alpha following stimulation with TLR7 ligand imiquimod and TLR9 ligand CpG ODN-2216 was also impaired in discordant patients even after 2 years following initiation of HAART. Lower IFN-alpha expression in the PDCs following TLR stimulation was further associated with lower expression of transcription factor, IFN regulatory factor-7. In contrast, production of TNF-alpha and IL-6 following TLR stimulation was comparable in both groups of patients, indicating that impaired reconstitution characteristics do not affect the capacity of PDCs to produce proinflammatory cytokines. The discordant patients had significantly lower baseline CD4 T cell counts and higher baseline viral load at the initiation of HAART implying that lower baseline CD4 T cell counts and higher plasma viral load are associated with impaired restoration of CD4 T cells and PDCs, thus, increasing the susceptibility of discordant patients toward opportunistic infections despite virological control.