Opioid-related xylazine toxicity manifesting as myonecrosis, rhabdomyolysis, multifocal ischemic cerebral infarcts, and cerebral edema.

This article provides a report of a case of organ dysfunction, myonecrosis, rhabdomyolysis, multifocal ischemic cerebral infarcts, and cerebral edema after a patient's use of xylazine and fentanyl. Within the US opioid epidemic, xylazine is emerging as a troubling national sub-story. The prevalence of xylazine within illicitly manufactured opioids and the proportion of opioid-involved overdose deaths with detected xylazine are rising dramatically, the latter increasing 276% between 2019 and 2022. A 27-year-old woman with opioid use disorder, active intravenous drug use, and prior bacteremia presented to our institution's emergency department (ED) with left lower extremity pain and associated weakness, new acute bilateral hearing loss, multiple electrolyte derangements, and cerebral infarcts followed by cerebral edema, leading to an emergent sub-occipital decompressive craniectomy and placement of an external ventricular drain. A definitive mechanism was not determined; however, we hypothesized that xylazine toxicity played a role in her clinical presentation, which could have future clinical implications, including the possibility to incorporate xylazine as part of toxicology screens.

Redox active plant phenolic, acetosyringone, for electrogenetic signaling.

Redox is a unique, programmable modality capable of bridging communication between biology and electronics. Previous studies have shown that the E. coli redox-responsive OxyRS regulon can be re-wired to accept electrochemically generated hydrogen peroxide (H2O2) as an inducer of gene expression. Here we report that the redox-active phenolic plant signaling molecule acetosyringone (AS) can also induce gene expression from the OxyRS regulon. AS must be oxidized, however, as the reduced state present under normal conditions cannot induce gene expression. Thus, AS serves as a "pro-signaling molecule" that can be activated by its oxidation-in our case by application of oxidizing potential to an electrode. We show that the OxyRS regulon is not induced electrochemically if the imposed electrode potential is in the mid-physiological range. Electronically sliding the applied potential to either oxidative or reductive extremes induces this regulon but through different mechanisms: reduction of O2 to form H2O2 or oxidation of AS. Fundamentally, this work reinforces the emerging concept that redox signaling depends more on molecular activities than molecular structure. From an applications perspective, the creation of an electronically programmed "pro-signal" dramatically expands the toolbox for electronic control of biological responses in microbes, including in complex environments, cell-based materials, and biomanufacturing.

Excite the unexcitable: engineering cells and redox signaling for targeted bioelectronic control.

The ever-growing influence of technology in our lives has led to an increasing interest in the development of smart electronic devices to interrogate and control biological systems. Recently, redox-mediated electrogenetics introduced a novel avenue that enables direct bioelectronic control at the genetic level. In this review, we discuss recent advances in methodologies for bioelectronic control, ranging from electrical stimulation to engineering efforts that allow traditionally unexcitable cells to be electrically 'programmable.' Alongside ion-transport signaling, we suggest redox as a route for rational engineering because it is a native form of electronic communication in biology. Using redox as a common language allows the interfacing of electronics and biology. This newfound connection opens a gateway of possibilities for next-generation bioelectronic tools.

Redox-enabled electronic interrogation and feedback control of hierarchical and networked biological systems.

Microelectronic devices can directly communicate with biology, as electronic information can be transmitted via redox reactions within biological systems. By engineering biology's native redox networks, we enable electronic interrogation and control of biological systems at several hierarchical levels: proteins, cells, and cell consortia. First, electro-biofabrication facilitates on-device biological component assembly. Then, electrode-actuated redox data transmission and redox-linked synthetic biology allows programming of enzyme activity and closed-loop electrogenetic control of cellular function. Specifically, horseradish peroxidase is assembled onto interdigitated electrodes where electrode-generated hydrogen peroxide controls its activity. E. coli's stress response regulon, oxyRS, is rewired to enable algorithm-based feedback control of gene expression, including an eCRISPR module that switches cell-cell quorum sensing communication from one autoinducer to another-creating an electronically controlled 'bilingual' cell. Then, these disparate redox-guided devices are wirelessly connected, enabling real-time communication and user-based control. We suggest these methodologies will help us to better understand and develop sophisticated control for biology.

Enhanced electrochemical measurement of ß-galactosidase activity in whole cells by coexpression of lactose permease, LacY.

Whole-cell biosensing links the sensing and computing capabilities of microbes to the generation of a detectable reporter. Whole cells enable dynamic biological computation (filtered noise, amplified signals, logic gating etc.). Enzymatic reporters enable in situ signal amplification. Electrochemical measurements are easily quantified and work in turbid environments. In this work we show how the coexpression of the lactose permease, LacY, dramatically improves electrochemical sensing of ß-galactosidase (LacZ) expressed as a reporter in whole cells. The permease facilitates transport of the LacZ substrate, 4-aminophenyl ß-d-galactopyranoside, which is converted to redox active p-aminophenol, which, in turn, is detected via cyclic voltammetry or chronocoulometry. We show a greater than fourfold improvement enabled by lacY coexpression in cells engineered to respond to bacterial signal molecules, pyocyanin and quorum-sensing autoinducer-2.

Quorum sensing componentry opens new lines of communication.

Autoinducer-2 is a key molecule for bacterial quorum sensing. New exporter structures may now help narrow the gap between biology and engineering.

Protein G: ß-galactosidase fusion protein for multi-modal bioanalytical applications.

ß-galactosidase (ß-gal) is one of the most prevalent markers of gene expression. Its activity can be monitored via optical and fluorescence microscopy, electrochemistry, and many other ways after slight modification using protein engineering. Here, we have constructed a chimeric version that incorporates a streptococcal protein G domain at the N-terminus of ß-gal that binds immunoglobins, namely IgG. This protein G: ß-galactosidase fusion enables ß-gal-based spectrophotometric and electrochemical measurements of IgG. Moreover, our results show linearity over an industrially relevant range. We demonstrate applicability with rapid spectroelectrochemical detection of IgG in several formats including using an electrochemical sensing interface that is rapidly assembled directly onto electrodes for incorporation into biohybrid devices. The fusion protein enables sensitive, linear, and rapid responses, and in our case, makes IgG measurements quite robust and simple, expanding the molecular diagnostics toolkit for biological measurement.

Characteristics and impact of bedside procedure services in the United States: A systematic review.

BACKGROUND: Bedside procedure services are increasingly employed within internal medicine departments to meet clinical needs and improve trainee education. Published literature on these largely comprises single-center studies; an updated systematic review is needed to synthesize available data. PURPOSE: This review examined published literature on the structure and function of bedside procedure services and their impact on clinical and educational outcomes (PROSPERO ID: 192466). DATA SOURCES: Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework, multiple databases were searched for publications from 2000 to 2021. STUDY SELECTION, DATA EXTRACTION, AND DATA SYNTHESIS: Thirteen single-center studies were identified, including 12 observational studies and 1 randomized trial. Data were synthesized in tabular and narrative format. Services were typically staffed by hospitalists or pulmonologists. At a minimum, each offered paracentesis, thoracentesis, and lumbar puncture. While there was considerable heterogeneity in service structures, these broadly fit either Model A (service performing the procedure) or Model B (service supervising the primary team). Procedure services led to increases in procedure volumes and self-efficacy among medical residents. Assessment of clinical outcomes was limited by heterogeneous definitions of complication rates and by sparse head-to-head data involving suitable comparators. Published data pointed to high success rates, low complication rates, and high patient satisfaction, with a recent study also demonstrating a decreased length of stay. CONCLUSIONS: There are relatively few published studies describing the characteristics of bedside procedure services and their impact on clinical and educational outcomes. Limited data point to considerable heterogeneity in service design, a positive impact on medical trainees, and a positive impact on patient-related outcomes.

Electrogenetic Signal Transmission and Propagation in Coculture to Guide Production of a Small Molecule, Tyrosine.

There are many strategies to actuate and control genetic circuits, including providing stimuli like exogenous chemical inducers, light, magnetic fields, and even applied voltage, that are orthogonal to metabolic activity. Their use enables actuation of gene expression for the production of small molecules and proteins in many contexts. Additionally, there are a growing number of reports wherein cocultures, consortia, or even complex microbiomes are employed for the production of biologics, taking advantage of an expanded array of biological function. Combining stimuli-responsive engineered cell populations enhances design space but increases complexity. In this work, we co-opt nature's redox networks and electrogenetically route control signals into a consortium of microbial cells engineered to produce a model small molecule, tyrosine. In particular, we show how electronically programmed short-lived signals (i.e., hydrogen peroxide) can be transformed by one population and propagated into sustained longer-distance signals that, in turn, guide tyrosine production in a second population building on bacterial quorum sensing that coordinates their collective behavior. Two design methodologies are demonstrated. First, we use electrogenetics to transform redox signals into the quorum sensing autoinducer, AI-1, that, in turn, induces a tyrosine biosynthesis pathway transformed into a second population. Second, we use the electrogenetically stimulated AI-1 to actuate expression of ptsH, boosting the growth rate of tyrosine-producing cells, augmenting both their number and metabolic activity. In both cases, we show how signal propagation within the coculture helps to ensure tyrosine production. We suggest that this work lays a foundation for employing electrochemical stimuli and engineered cocultures for production of molecular products in biomanufacturing environments.

Parsed synthesis of pyocyanin via co-culture enables context-dependent intercellular redox communication.

BACKGROUND: Microbial co-cultures and consortia are of interest in cell-based molecular production and even as "smart" therapeutics in that one can take advantage of division of labor and specialization to expand both the range of available functions and mechanisms for control. The development of tools that enable coordination and modulation of consortia will be crucial for future application of multi-population cultures. In particular, these systems would benefit from an expanded toolset that enables orthogonal inter-strain communication. RESULTS: We created a co-culture for the synthesis of a redox-active phenazine signaling molecule, pyocyanin (PYO), by dividing its synthesis into the generation of its intermediate, phenazine carboxylic acid (PCA) from the first strain, followed by consumption of PCA and generation of PYO in a second strain. Interestingly, both PCA and PYO can be used to actuate gene expression in cells engineered with the soxRS oxidative stress regulon, although importantly this signaling activity was found to depend on growth media. That is, like other signaling motifs in bacterial systems, the signaling activity is context dependent. We then used this co-culture's phenazine signals in a tri-culture to modulate gene expression and production of three model products: quorum sensing molecule autoinducer-1 and two fluorescent marker proteins, eGFP and DsRed. We also showed how these redox-based signals could be intermingled with other quorum-sensing (QS) signals which are more commonly used in synthetic biology, to control complex behaviors. To provide control over product synthesis in the tri-cultures, we also showed how a QS-induced growth control module could guide metabolic flux in one population and at the same time guide overall tri-culture function. Specifically, we showed that phenazine signal recognition, enabled through the oxidative stress response regulon soxRS, was dependent on media composition such that signal propagation within our parsed synthetic system could guide different desired outcomes based on the prevailing environment. In doing so, we expanded the range of signaling molecules available for coordination and the modes by which they can be utilized to influence overall function of a multi-population culture. CONCLUSIONS: Our results show that redox-based signaling can be intermingled with other quorum sensing signaling in ways that enable user-defined control of microbial consortia yielding various outcomes defined by culture medium. Further, we demonstrated the utility of our previously designed growth control module in influencing signal propagation and metabolic activity is unimpeded by orthogonal redox-based signaling. By exploring novel multi-modal strategies for guiding communication and consortia outcome, the concepts introduced here may prove to be useful for coordination of multiple populations within complex microbial systems.

Identifying Key Drivers of Wildfires in the Contiguous US Using Machine Learning and Game Theory Interpretation.

Understanding the complex interrelationships between wildfire and its environmental and anthropogenic controls is crucial for wildfire modeling and management. Although machine learning (ML) models have yielded significant improvements in wildfire predictions, their limited interpretability has been an obstacle for their use in advancing understanding of wildfires. This study builds an ML model incorporating predictors of local meteorology, land-surface characteristics, and socioeconomic variables to predict monthly burned area at grid cells of 0.25° × 0.25° resolution over the contiguous United States. Besides these predictors, we construct and include predictors representing the large-scale circulation patterns conducive to wildfires, which largely improves the temporal correlations in several regions by 14%-44%. The Shapley additive explanation is introduced to quantify the contributions of the predictors to burned area. Results show a key role of longitude and latitude in delineating fire regimes with different temporal patterns of burned area. The model captures the physical relationship between burned area and vapor pressure deficit, relative humidity (RH), and energy release component (ERC), in agreement with the prior findings. Aggregating the contribution of predictor variables of all the grids by region, analyses show that ERC is the major contributor accounting for 14%-27% to large burned areas in the western US. In contrast, there is no leading factor contributing to large burned areas in the eastern US, although large-scale circulation patterns featuring less active upper-level ridge-trough and low RH two months earlier in winter contribute relatively more to large burned areas in spring in the southeastern US.

A Redox-Based Autoinduction Strategy to Facilitate Expression of 5xCys-Tagged Proteins for Electrobiofabrication.

Biofabrication utilizes biological materials and biological means, or mimics thereof, for assembly. When interfaced with microelectronics, electrobiofabricated assemblies enable exquisite sensing and reporting capabilities. We recently demonstrated that thiolated polyethylene glycol (PEG-SH) could be oxidatively assembled into a thin disulfide crosslinked hydrogel at an electrode surface; with sufficient oxidation, extra sulfenic acid groups are made available for covalent, disulfide coupling to sulfhydryl groups of proteins or peptides. We intentionally introduced a polycysteine tag (5xCys-tag) consisting of five consecutive cysteine residues at the C-terminus of a Streptococcal protein G to enable its covalent coupling to an electroassembled PEG-SH film. We found, however, that its expression and purification from E. coli was difficult, owing to the extra cysteine residues. We developed a redox-based autoinduction methodology that greatly enhanced the yield, especially in the soluble fraction of E. coli extracts. The redox component involved the deletion of oxyRS, a global regulator of the oxidative stress response and the autoinduction component integrated a quorum sensing (QS) switch that keys the secreted QS autoinducer-2 to induction. Interestingly, both methods helped when independently employed and further, when used in combination (i.e., autodinduced oxyRS mutant) the results were best-we found the highest total yield and highest yield in the soluble fraction. We hypothesize that the production host was less prone to severe metabolic perturbations that might reduce yield or drive sequestration of the -tagged protein into inclusion bodies. We expect this methodology will be useful for the expression of many such Cys-tagged proteins, ultimately enabling a diverse array of functionalized devices.

Simple, rapidly electroassembled thiolated PEG-based sensor interfaces enable rapid interrogation of antibody titer and glycosylation.

Process conditions established during the development and manufacture of recombinant protein therapeutics dramatically impacts their quality and clinical efficacy. Technologies that enable rapid assessment of product quality are critically important. Here, we describe the development of sensor interfaces that directly connect to electronics and enable near real-time assessment of antibody titer and N-linked galactosylation. We make use of a spatially resolved electroassembled thiolated polyethylene glycol hydrogel that enables electroactivated disulfide linkages. For titer assessment, we constructed a cysteinylated protein G that can be linked to the thiolated hydrogel allowing for robust capture and assessment of antibody concentration. For detecting galactosylation, the hydrogel is linked with thiolated sugars and their corresponding lectins, which enables antibody capture based on glycan pattern. Importantly, we demonstrate linear assessment of total antibody concentration over an industrially relevant range and the selective capture and quantification of antibodies with terminal ß-galactose glycans. We also show that the interfaces can be reused after surface regeneration using a low pH buffer. Our functionalized interfaces offer advantages in their simplicity, rapid assembly, connectivity to electronics, and reusability. As they assemble directly onto electrodes that also serve as I/O registers, we envision incorporation into diagnostic platforms including those in manufacturing settings.

Interactive Materials for Bidirectional Redox-Based Communication.

Emerging research indicates that biology routinely uses diffusible redox-active molecules to mediate communication that can span biological systems (e.g., nervous and immune) and even kingdoms (e.g., a microbiome and its plant/animal host). This redox modality also provides new opportunities to create interactive materials that can communicate with living systems. Here, it is reported that the fabrication of a redox-active hydrogel film can autonomously synthesize a H2 O2 signaling molecule for communication with a bacterial population. Specifically, a catechol-conjugated/crosslinked 4-armed thiolated poly(ethylene glycol) hydrogel film is electrochemically fabricated in which the added catechol moieties confer redox activity: the film can accept electrons from biological reductants (e.g., ascorbate) and donate electrons to O2 to generate H2 O2 . Electron-transfer from an Escherichia coli culture poises this film to generate the H2 O2 signaling molecule that can induce bacterial gene expression from a redox-responsive operon. Overall, this work demonstrates that catecholic materials can participate in redox-based interactions that elicit specific biological responses, and also suggests the possibility that natural phenolics may be a ubiquitous biological example of interactive materials.

Quorum Sensing Communication: Molecularly Connecting Cells, Their Neighbors, and Even Devices.

Quorum sensing (QS) is a molecular signaling modality that mediates molecular-based cell-cell communication. Prevalent in nature, QS networks provide bacteria with a method to gather information from the environment and make decisions based on the intel. With its ability to autonomously facilitate both inter- and intraspecies gene regulation, this process can be rewired to enable autonomously actuated, but molecularly programmed, genetic control. On the one hand, novel QS-based genetic circuits endow cells with smart functions that can be used in many fields of engineering, and on the other, repurposed QS circuitry promotes communication and aids in the development of synthetic microbial consortia. Furthermore, engineered QS systems can probe and intervene in interkingdom signaling between bacteria and their hosts. Lastly, QS is demonstrated to establish conversation with abiotic materials, especially by taking advantage of biological and even electronically induced assembly processes; such QS-incorporated biohybrid devices offer innovative ways to program cell behavior and biological function.

Nonbacterial Thrombotic Endocarditis Due to Primary Gallbladder Malignancy with Recurrent Stroke Despite Anticoagulation: Case Report and Literature Review.

Nonbacterial thrombotic endocarditis (NBTE) associated with malignancy is rare; its infrequency and similarity to other diagnoses make it a significant diagnostic challenge. A 63-year-old woman on rivaroxaban for prior deep vein thrombosis presented with left upper extremity weakness and left facial droop with imaging demonstrating multiple strokes. Echocardiograms revealed mitral and aortic valve vegetations. The patient was switched to apixaban and started on vancomycin and ceftriaxone for presumed culture-negative endocarditis. Despite continuing apixaban, her hospital course was complicated by new acute embolic infarcts. Workup confirmed non-mucinous metastatic biliary adenocarcinoma. The patient was placed on a heparin drip then switched to low molecular weight heparin without further embolic events and was discharged to a rehabilitation facility in stable condition with plans for chemotherapy as an outpatient. These clinical, imaging, and histologic findings were consistent with a rare case of NBTE associated with primary non-mucinous gallbladder malignancy complicated by recurrent strokes in which direct oral anticoagulants did not provide adequate anticoagulation.

Epidermal CYLD inactivation sensitizes mice to the development of sebaceous and basaloid skin tumors.

The deubiquitinase-encoding gene Cyld displays a dominant genetic linkage to a wide spectrum of skin-appendage tumors, which could be collectively designated as CYLD mutant-syndrome (CYLDm-syndrome). Despite recent advances, little is understood about the molecular mechanisms responsible for this painful and difficult-to-treat skin disease. Here, we generated a conditional mouse model with epidermis-targeted expression of a catalytically deficient CYLDm through K14-Cre-mediated deletion of exon 9 (hereafter refer to CyldEΔ9/Δ9 ). CyldEΔ9/Δ9 mice were born alive but developed hair and sebaceous gland abnormalities and dental defects at 100% and 60% penetrance, respectively. Upon topical challenge with DMBA/TPA, these animals primarily developed sebaceous and basaloid tumors resembling human CYLDm-syndrome as opposed to papilloma, which is most commonly induced in WT mice by this treatment. Molecular analysis revealed that TRAF6-K63-Ubiquitination (K63-Ub), c-Myc-K63-Ub, and phospho-c-Myc (S62) were markedly elevated in CyldEΔ9/Δ9 skin. Topical treatment with a pharmacological c-Myc inhibitor induced sebaceous and basal cell apoptosis in CyldEΔ9/Δ9 skin. Consistently, c-Myc activation was readily detected in human cylindroma and sebaceous adenoma. Taken together, our findings demonstrate that CyldEΔ9/Δ9 mice represent a disease-relevant animal model and identify TRAF6 and c-Myc as potential therapeutic targets for CYLDm-syndrome.