Design and proof of concept for targeted phage-based COVID-19 vaccination strategies with a streamlined cold-free supply chain.

Development of effective vaccines against coronavirus disease 2019 (COVID-19) is a global imperative. Rapid immunization of the entire human population against a widespread, continually evolving, and highly pathogenic virus is an unprecedented challenge, and different vaccine approaches are being pursued. Engineered filamentous bacteriophage (phage) particles have unique potential in vaccine development due to their inherent immunogenicity, genetic plasticity, stability, cost-effectiveness for large-scale production, and proven safety profile in humans. Herein we report the development and initial evaluation of two targeted phage-based vaccination approaches against SARS-CoV-2: dual ligand peptide-targeted phage and adeno-associated virus/phage (AAVP) particles. For peptide-targeted phage, we performed structure-guided antigen design to select six solvent-exposed epitopes of the SARS-CoV-2 spike (S) protein. One of these epitopes displayed on the major capsid protein pVIII of phage induced a specific and sustained humoral response when injected in mice. These phage were further engineered to simultaneously display the peptide CAKSMGDIVC on the minor capsid protein pIII to enable their transport from the lung epithelium into the systemic circulation. Aerosolization of these "dual-display" phage into the lungs of mice generated a systemic and specific antibody response. In the second approach, targeted AAVP particles were engineered to deliver the entire S protein gene under the control of a constitutive CMV promoter. This induced tissue-specific transgene expression, stimulating a systemic S protein-specific antibody response in mice. With these proof-of-concept preclinical experiments, we show that both targeted phage- and AAVP-based particles serve as robust yet versatile platforms that can promptly yield COVID-19 vaccine prototypes for translational development.

Genetic and Structural Analysis of SARS-CoV-2 Spike Protein for Universal Epitope Selection.

Evaluation of immunogenic epitopes for universal vaccine development in the face of ongoing SARS-CoV-2 evolution remains a challenge. Herein, we investigate the genetic and structural conservation of an immunogenically relevant epitope (C662-C671) of spike (S) protein across SARS-CoV-2 variants to determine its potential utility as a broad-spectrum vaccine candidate against coronavirus diseases. Comparative sequence analysis, structural assessment, and molecular dynamics simulations of C662-C671 epitope were performed. Mathematical tools were employed to determine its mutational cost. We found that the amino acid sequence of C662-C671 epitope is entirely conserved across the observed major variants of SARS-CoV-2 in addition to SARS-CoV. Its conformation and accessibility are predicted to be conserved, even in the highly mutated Omicron variant. Costly mutational rate in the context of energy expenditure in genome replication and translation can explain this strict conservation. These observations may herald an approach to developing vaccine candidates for universal protection against emergent variants of coronavirus.

Underutilization of advanced presurgical studies and high rates of vagus nerve stimulation for drug-resistant epilepsy: a single-center experience and recommendations.

INTRODUCTION: Epilepsy surgery continues to be profoundly underutilized despite its safety and effectiveness. We sought to investigate factors that may contribute to this phenomenon, with a particular focus on the antecedent underutilization of appropriate preoperative studies. METHODS: We reviewed patient data from a pediatric epilepsy clinic over an 18-month period. Patients with drug-resistant epilepsy (DRE) were categorized according to brain magnetic resonance imaging (MRI) findings (lesional, MRI-negative, or multifocal abnormalities) and type of epilepsy diagnosis based on semiology and electroencephalography (EEG) (focal or generalized). We then analyzed the rates of diagnostic test utilization, surgical referral, and subsequent epilepsy surgery as well as vagus nerve stimulation (VNS). RESULTS: Of the 249 patients with a diagnosis of epilepsy, 138 (55.4%) were found to have DRE. Excluding the 10 patients with DRE who did not undergo MRI, 76 patients (59.4%) were found to be MRI-negative (non-lesional epilepsy), 37 patients (28.9%) were found to have multifocal abnormalities, and 15 patients (11.7%) were found to have a single epileptogenic lesion on MRI (lesional epilepsy). Positron emission tomography (PET) and single-photon emission computed tomography (SPECT) were each completed in nine patients (7.0%) and magnetoencephalography (MEG) in four patients (3.1%). Despite the low utilization rate of adjunctive studies, over half (56.3%) ultimately underwent VNS alone, and 8.6% ultimately underwent definitive intracranial resection or disconnection surgery. CONCLUSIONS: The underutilization of appropriate non-invasive, presurgical testing in patients with focal DRE may in part explain the continued underutilization of definitive, resective/disconnective surgery. For patients without access to a high-volume, multidisciplinary surgical epilepsy center, adjunctive presurgical studies [e.g., PET, SPECT, MEG, electrical source imaging (ESI), EEG-functional magnetic resonance imaging (fMRI)], even when available, are rarely ordered, and this may contribute to excessive rates of VNS in lieu of definitive intracranial surgery.

Recruitment of Jub by α-catenin promotes Yki activity and Drosophila wing growth.

The Hippo signaling network controls organ growth through YAP family transcription factors, including the Drosophila Yorkie protein. YAP activity is responsive to both biochemical and biomechanical cues, with one key input being tension within the F-actin cytoskeleton. Several potential mechanisms for the biomechanical regulation of YAP proteins have been described, including tension-dependent recruitment of Ajuba family proteins, which inhibit kinases that inactivate YAP proteins, to adherens junctions. Here, we investigate the mechanism by which the Drosophila Ajuba family protein Jub is recruited to adherens junctions, and the contribution of this recruitment to the regulation of Yorkie. We identify α-catenin as the mechanotransducer responsible for tension-dependent recruitment of Jub by identifying a region of α-catenin that associates with Jub, and by identifying a region, which when deleted, allows constitutive, tension-independent recruitment of Jub. We also show that increased Jub recruitment to α-catenin is associated with increased Yorkie activity and wing growth, even in the absence of increased cytoskeletal tension. Our observations establish α-catenin as a multi-functional mechanotransducer and confirm Jub recruitment to α-catenin as a key contributor to biomechanical regulation of Hippo signaling.

Frozen conflict in the midst of a global pandemic: potential impact on mental health in Armenian border communities.

Armenia has been in a conflict with its neighbor, Azerbaijan, since 1988. Civilians in Tavush Province are regularly affected by ceasefire violations along the armed border with recent escalations further threatening the population's safety. In the midst of the COVID-19 pandemic, concerns regarding the mental health of border village residents in Armenia are prevalent. We present context-related factors of psychiatric illness, the prevalence of mental health disorders, and the state of mental health services in Armenia. We recommend directing greater attention towards the mental health status of civilians residing in conflict zones during the ongoing COVID-19 pandemic.

Complications associated with deep brain stimulation for Parkinson's disease: a MAUDE study.

INTRODUCTION: Deep brain stimulation (DBS) is a common surgical option for the treatment of medically refractory Parkinson's disease (PD). Manufacturer and User Facility Device Experience (MAUDE), a United States Food and Drug Administration (FDA)-compiled database of adverse event reports related to medical devices, is a public resource that can provide insight into the relative frequency of complications and patient complaints. MATERIALS AND METHODS: We accessed the MAUDE database and queried for adverse reports for deep brain stimulators implanted for PD from January 1, 2009 to December 31, 2018. Complaints were classified into device malfunction, patient non-compliance, patient complaint, surgically managed complications (i.e. complications that are corrected via surgery), and death. Patient complaints were further stratified into ineffective stimulation, shock, overstimulation, battery-related problems, or pain at the pulse generator site. Surgically managed complications were classified as intraoperative complications, impedance, migration, erosion, infection, lead fracture, and lead disconnection. Each event could receive multiple classifications and subclassifications. RESULTS: A total of 4,189 adverse event reports was obtained. These encompassed 2,805 patient complaints. Within this group, 797 (28%) events were classified as ineffective stimulation. There were 1,382 surgically managed complications, 104 (8%) of which were intraoperative complications, 757 (55%) documented impedance issues, 381 (28%) infections, and 413 (30%) lead-related issues. There were 53 documented deaths. CONCLUSIONS: The MAUDE database has potential use as a real time monitor for elucidating the relative occurrence of complications associated with deep brain stimulation. It also allows for the analysis of device-related complications in specific patient populations. Although the database is useful in this endeavor, it requires improvements particularly in the standardization of reporting adverse events.

Neuromodulatory hacking: a review of the technology and security risks of spinal cord stimulation.

BACKGROUND: Spinal cord stimulation (SCS) is a neuromodulatory technique used to relieve chronic pain. Previous instances of malicious remote control of implantable medical devices, including insulin delivery pumps and implantable cardiac defibrillators, have been documented. Though no cases of neuromodulatory hacking have been recorded outside of the academic setting, an understanding of SCS technology and the possible consequences of manipulation is important in promoting safety. METHODS: We review the components and implantation protocol of a SCS system, the functionality and technological specifications for SCS systems in the global market based on their device manuals, and patient- and clinician-specific adjustable factors. Furthermore, we assess documented instances of implantable medical device hacking and speculate on the potential harms of targeting SCS systems. RESULTS: SCS systems from Abbott Laboratories, Boston Scientific, Medtronic, and Nevro have unique functionality and technological specifications. Six parameters in device control can potentially be targeted and elicit various harms, including loss of therapeutic effect, accelerated battery drainage, paresthesia in unintended locations, muscle weakness or dysfunction, tissue burn, and electrical shock. CONCLUSIONS: Based on the history of implantable medical device hacking, SCS systems may also be susceptible to manipulation. As the prevalence of SCS use increases and SCS systems continuously evolve in the direction of wireless control and compatibility with mobile devices, appropriate measures should be taken by manufacturers and governmental agencies to ensure safety.

The historical evolution of microvascular decompression for trigeminal neuralgia: from Dandy's discovery to Jannetta's legacy.

Although the symptoms of trigeminal neuralgia (TN) have been well described throughout the history of medicine, its etiology was initially not well understood by most surgeons. The standard procedure used to treat TN today, microvascular decompression (MVD), evolved due to the efforts of numerous neurosurgeons throughout the twentieth century. Walter Dandy was the first to utilize the cerebellar (suboccipital) approach to expose the trigeminal nerve for partial sectioning. He made unique observations about the compression of the trigeminal nerve by nearby structures, such as vasculature and tumors, in TN patients. In the 1920s, Dandy unintentionally performed the first MVD of the trigeminal nerve root. In the 1950s, Palle Taarnhøj treated a TN patient by performing the first intentional decompressive procedure on the trigeminal nerve root solely through the removal of a compressive tumor. By the 1960s, W. James Gardner was demonstrating that the removal of offending lesion(s) or decompression of nearby vasculature alleviated pressure on the trigeminal nerve and the pain associated with TN. By the 1990s, Peter Jannetta proved Dandy's original hypothesis; he visualized the compression of the trigeminal nerve at the root entry zone in TN patients using an intraoperative microscope. In this paper, we recount the historical evolution of MVD for the treatment of TN.

Generative artificial intelligence performs rudimentary structural biology modeling.

Natural language-based generative artificial intelligence (AI) has become increasingly prevalent in scientific research. Intriguingly, capabilities of generative pre-trained transformer (GPT) language models beyond the scope of natural language tasks have recently been identified. Here we explored how GPT-4 might be able to perform rudimentary structural biology modeling. We prompted GPT-4 to model 3D structures for the 20 standard amino acids and an α-helical polypeptide chain, with the latter incorporating Wolfram mathematical computation. We also used GPT-4 to perform structural interaction analysis between the anti-viral nirmatrelvir and its target, the SARS-CoV-2 main protease. Geometric parameters of the generated structures typically approximated close to experimental references. However, modeling was sporadically error-prone and molecular complexity was not well tolerated. Interaction analysis further revealed the ability of GPT-4 to identify specific amino acid residues involved in ligand binding along with corresponding bond distances. Despite current limitations, we show the current capacity of natural language generative AI to perform basic structural biology modeling and interaction analysis with atomic-scale accuracy.

Generative artificial intelligence performs rudimentary structural biology modeling.

Natural language-based generative artificial intelligence (AI) has become increasingly prevalent in scientific research. Intriguingly, capabilities of generative pre-trained transformer (GPT) language models beyond the scope of natural language tasks have recently been identified. Here we explored how GPT-4 might be able to perform rudimentary structural biology modeling. We prompted GPT-4 to model 3D structures for the 20 standard amino acids and an α-helical polypeptide chain, with the latter incorporating Wolfram mathematical computation. We also used GPT-4 to perform structural interaction analysis between nirmatrelvir and its target, the SARS-CoV-2 main protease. Geometric parameters of the generated structures typically approximated close to experimental references. However, modeling was sporadically error-prone and molecular complexity was not well tolerated. Interaction analysis further revealed the ability of GPT-4 to identify specific amino acid residues involved in ligand binding along with corresponding bond distances. Despite current limitations, we show the capacity of natural language generative AI to perform basic structural biology modeling and interaction analysis with atomic-scale accuracy.

Gross Total Resection of a Ruptured Micro-arteriovenous Malformation within the Cerebellar Peduncle: A Case Report and Qualitative Review of the Literature.

Deep-seated micro-arteriovenous malformations (micro-AVMs) may pose a challenge for complete yet safe resection. We propose the strategic placement of two to three microaneurysm clips throughout the hemorrhage cavity to successfully localize the micro-AVM nidus via digital subtraction angiography (DSA). We successfully demonstrate this novel method in a 15-year-old adolescent boy with cerebellar intraparenchymal hemorrhage who underwent hematoma evacuation and expansile duraplasty. He was found to have a 1-cm nidus of a micro-AVM with early venous drainage located in the right middle cerebellar peduncle. Five days later, we proceeded to resect the micro-AVM; however, a clear nidus or bleeding source was unable to be localized intraoperatively despite the use of stereotactic neuronavigation. In turn, we placed two mini-aneurysm clips superiorly and inferiorly within the hematoma cavity, which led to successful localization via DSA and complete resection. No surgical complications occurred. The patient completely recovered from right-sided weakness and dysarthria 6 to 12 months postoperatively. Our technique allows for the rapid localization and complete resection of micro-AVM nidi when stereotactic neuronavigation is inadequate.

Medical Education in Armenia: An Overview.

This article serves to describe the medical education system of Armenia, a country located in the cross-section of Europe and Asia. Similar to other countries in the region, its medical education system is structured into undergraduate (6 years), postgraduate (1-4 years), and continuing education components. Its largest medical university, Yerevan State Medical University (YSMU), is the predominant institute for medical education and has enrollment of not only Armenian citizens, but also international students from India, Iran, Russia, and other countries. According to publication metrics, research activity at YSMU is increasing. Finally, the unique relationship between the country and its global diaspora has facilitated collaborative efforts in not only medical education, but also the delivery of care and capacity building. Significant challenges remain for each stage of medical education, such as the lack of standardized licensing or board examinations and oversight of the number of resident physicians per specialty.

A modeling-based approach to optimize COVID-19 vaccine dosing schedules for improved protection.

While the development of different vaccines has slowed the dissemination of SARS-CoV-2, the occurrence of breakthrough infections continues to fuel the pandemic. As a strategy to secure at least partial protection, with a single dose of a given COVID-19 vaccine to maximum possible fraction of the population, delayed administration of subsequent doses (or boosters) has been implemented in many countries. However, waning immunity and emergence of new variants of SARS-CoV-2 suggest that such measures may jeopardize the attainment of herd immunity due to intermittent lapses in protection. Optimizing vaccine dosing schedules could thus make the difference between periodic occurrence of breakthrough infections or effective control of the pandemic. To this end, we have developed a mechanistic mathematical model of adaptive immune response to vaccines and demonstrated its applicability to COVID-19 mRNA vaccines as a proof-of-concept for future outbreaks. The model was thoroughly calibrated against multiple clinical datasets involving immune response to SARS-CoV-2 infection and mRNA vaccines in healthy and immunocompromised subjects (cancer patients undergoing therapy); the model showed robust clinical validation by accurately predicting neutralizing antibody kinetics, a correlate of vaccine-induced protection, in response to multiple doses of mRNA vaccines. Importantly, we estimated population vulnerability to breakthrough infections and predicted tailored vaccination dosing schedules to maximize protection and thus minimize breakthrough infections, based on the immune status of a sub-population. We have identified a critical waiting window for cancer patients (or, immunocompromised subjects) to allow recovery of the immune system (particularly CD4+ T-cells) for effective differentiation of B-cells to produce neutralizing antibodies and thus achieve optimal vaccine efficacy against variants of concern, especially between the first and second doses. Also, we have obtained optimized dosing schedules for subsequent doses in healthy and immunocompromised subjects, which vary from the CDC-recommended schedules, to minimize breakthrough infections. The developed modeling tool is based on generalized adaptive immune response to antigens and can thus be leveraged to guide vaccine dosing schedules during future outbreaks.

A modeling-based approach to optimize COVID-19 vaccine dosing schedules for improved protection.

While the development of different vaccines slowed the dissemination of SARS-CoV-2, the occurrence of breakthrough infections has continued to fuel the COVID-19 pandemic. To secure at least partial protection in the majority of the population through 1 dose of a COVID-19 vaccine, delayed administration of boosters has been implemented in many countries. However, waning immunity and emergence of new variants of SARS-CoV-2 suggest that such measures may induce breakthrough infections due to intermittent lapses in protection. Optimizing vaccine dosing schedules to ensure prolonged continuity in protection could thus help control the pandemic. We developed a mechanistic model of immune response to vaccines as an in silico tool for dosing schedule optimization. The model was calibrated with clinical data sets of acquired immunity to COVID-19 mRNA vaccines in healthy and immunocompromised participants and showed robust validation by accurately predicting neutralizing antibody kinetics in response to multiple doses of COVID-19 mRNA vaccines. Importantly, by estimating population vulnerability to breakthrough infections, we predicted tailored vaccination dosing schedules to minimize breakthrough infections, especially for immunocompromised individuals. We identified that the optimal vaccination schedules vary from CDC-recommended dosing, suggesting that the model is a valuable tool to optimize vaccine efficacy outcomes during future outbreaks.

Modeling of ACE2 and antibodies bound to SARS-CoV-2 provides insights into infectivity and immune evasion.

Given the COVID-19 pandemic, there is interest in understanding ligand-receptor features and targeted antibody-binding attributes against emerging SARS-CoV-2 variants. Here, we developed a large-scale structure-based pipeline for analysis of protein-protein interactions regulating SARS-CoV-2 immune evasion. First, we generated computed structural models of the Spike protein of 3 SARS-CoV-2 variants (B.1.1.529, BA.2.12.1, and BA.5) bound either to a native receptor (ACE2) or to a large panel of targeted ligands (n = 282), which included neutralizing or therapeutic monoclonal antibodies. Moreover, by using the Barnes classification, we noted an overall loss of interfacial interactions (with gain of new interactions in certain cases) at the receptor-binding domain (RBD) mediated by substituted residues for neutralizing complexes in classes 1 and 2, whereas less destabilization was observed for classes 3 and 4. Finally, an experimental validation of predicted weakened therapeutic antibody binding was performed in a cell-based assay. Compared with the original Omicron variant (B.1.1.529), derivative variants featured progressive destabilization of antibody-RBD interfaces mediated by a larger set of substituted residues, thereby providing a molecular basis for immune evasion. This approach and findings provide a framework for rapidly and efficiently generating structural models for SARS-CoV-2 variants bound to ligands of mechanistic and therapeutic value.

Corpus Callosotomy in the Modern Era: Origins, Efficacy, Technical Variations, Complications, and Indications.

Corpus callosotomy is among the oldest surgeries performed for drug-resistant epilepsy. Since it was first performed in 1940, numerous studies have assessed its outcomes in various patient populations in addition to describing different extents of sectioning and emerging technologies (i.e., endoscopic, laser interstitial thermal therapy, and radiosurgery). To capture the current state and offer a reappraisal, we comprehensively review the origins of corpus callosotomy, efficacy for various seizure types, technical variations, complications, and indications and compare the procedure with vagus nerve stimulation therapy, which has similar indications. We consider corpus callosotomy to be a safe and efficacious procedure, which should be considered by clinicians when appropriate. Furthermore, it can play an important role in treating patients with drug-resistant epilepsy when appropriate in low-to-middle-income countries where resources are limited.

Self-efficacy and knowledge in pediatrics among family medicine physicians in Armenia: A survey study.

Background: Armenia has trained physicians to practice family medicine (FM) for over 20 years. The pediatric population comprises a significant proportion of patients seen by FM practices, yet to date, there have been no studies assessing the knowledge and self-efficacy of FM physicians regarding pediatric care. As the first step is needs assessment to improve the quality of care, this study aims to assess the self-efficacy and knowledge of FM physicians regarding the care of pediatric patients. Materials and Methods: We distributed a survey to attendees at an FM conference in Lori Province, Armenia. The survey instrument assessed demographics and experience, self-efficacy in providing pediatric care, and pediatric knowledge via questions adapted from the American Board of Family Medicine (ABFM). Results: Eighty-seven percent of participants were female. Roughly half (45%) had trained through an FM residency program, while the remainder had retrained to become FM physicians following a residency in another field. Almost all (97%) practiced outside of the capital city, Yerevan. About half believed that their didactic (51%) and clinical education (48%) prepared them either "extremely" or "very" well. Overall, there was no clear relationship between participants' reported self-efficacy in a given area of pediatrics and their score in that area on the knowledge portion of the survey. Conclusions: Our findings reveal opportunities for improvement in knowledge related to pediatric care in FM physicians in Armenia, as well as a lack of relationship between reported self-efficacy and knowledge. Thus, future programs should not rely solely on self-reported gaps to identify or prioritize areas of focus. Further study is recommended in other specialties in Armenia and internationally to improve future programs.

Surgical Clip Ligation of Anterior Communicating Artery Aneurysm in a Resource-Limited Setting.

Anterior communicating artery (ACOM) aneurysm clipping with intraoperative measures to ensure total occlusion and avoid ischemic complications is standard in countries such as the United States. However, alternatives need to be considered in resource-limited settings. The clipping of an unruptured, superiorly projecting ACOM aneurysm in a resource-limited setting is presented and special nuances that optimize safety are described. Careful surgical technique, meticulous identification of relevant anatomy, post-ligation inspection of the aneurysm and adjacent vessels, and possibly needle puncture of the aneurysm dome are critical to achieve favorable results.

Sodium Fluorescein-Guided Gross Total Resection of Pediatric Exophytic Brainstem Glioma: 2-Dimensional Operative Video.

Brainstem gliomas comprise 10% to 20% of pediatric intracranial tumors.1 Gross total resection is associated with the greatest long-term survival.1 However, due to the eloquence of surrounding brain tissue, an aggressive resection is not always achievable and can be associated with significant risk.2 Sodium fluorescein can be used to help differentiate between tumor and normal tissue.3,4 In this operative video, we demonstrate the step-by-step technique to utilize fluorescence in surgically resecting an exophytic glioma arising from the midbrain in a 16-yr-old male. Technical nuances are highlighted in this operative video, including the use of the YELLOW 560 (Zeiss) filter to differentiate fluorescent tumor from normal tissue as well as strategic splitting of the tentorium to expose the supratentorial component of the tumor. A decrease in motor potentials of the right leg during the case did not translate into neurological worsening postoperatively; at 3-mo follow-up, the patient attests to better strength and coordination on his affected side. In summary, sodium fluorescein can be used as a critical adjunctive tool for successful surgery in the case of a brainstem tumor. Alternatives to this procedure included gross total resection with 5-aminolevulinic acid, subtotal resection with chemotherapy, and active monitoring, but were not chosen due to their limitations in this clinical case.5-7 Appropriate patient consent was obtained to perform this procedure and present this clinical case and surgical video for academic purposes.