A decade after SARS: strategies for controlling emerging coronaviruses

Two novel coronaviruses have emerged in humans in the 21st century, Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle East Respiratory Syndrome human coronavirus (MERS-CoV), both of which cause acute respiratory distress syndrome (ARDS) and have high mortality rates. There are no clinically approved vaccines or antiviral drugs available for either of these infections; thus, a priority in the field is the development of effective therapeutic and preventive strategies that can be readily applied to new emergent strains. This review will: describe the emergence and identification of novel human coronaviruses over the last 10 years; review their key biological features, including tropism and receptor use; and summarize approaches to develop broadly effective vaccines

Each of the Eight Simian Hemorrhagic Fever Virus Minor Structural Proteins is Functionally Important

The simian hemorrhagic fever virus (SHFV) genome differs from those of other members of the family Arterivirus in encoding two adjacent sets of four minor structural protein open reading frames (ORFs). A stable, full-length, infectious SHFV-LVR cDNA clone was constructed. Virus produced from this clone had replication characteristics similar to those of the parental virus. A subgenomic mRNA was identified for the SHFV ORF previously identified as 2b. As an initial means of analyzing the functional relevance of each of the SHFV minor structural proteins, a set of mutant infectious clones was generated, each with the start codon of one minor structural protein ORF mutated. Different phenotypes were observed for each ortholog of the pairs of minor glycoproteins and all of the eight minor structural proteins were required for the production of infectious extracellular virus indicating that the duplicated sets of SHFV minor structural proteins are not functionally redundant

Escape from Human Monoclonal Antibody Neutralization Affects In Vitro and In Vivo Fitness of Severe Acute Respiratory Syndrome Coronavirus

Severe Acute Respiratory Syndrome (SARS) emerged as a human disease in 2002 and detailed phylogenetic analysis and epidemiological studies have suggested that the SARS-Coronavirus (SARS-CoV) originated from animals. The Spike (S) glycoprotein has been identified as a major target of protective immunity and contains at least three regions that are targeted by neutralizing antibodies in the S1 and S2 domains. We previously characterized a panel of neutralizing human monoclonal antibodies (MAbs) but the majority of epitopes recognized by the MAbs remained unknown

Increased Antibody Affinity Confers Broad In Vitro Protection against Escape Mutants of Severe Acute Respiratory Syndrome Coronavirus

Even though the effect of antibody affinity on neutralization potency is well documented, surprisingly, its impact on neutralization breadth and escape has not been systematically determined. Here, random mutagenesis and DNA shuffling of the single-chain variable fragment of the neutralizing antibody 80R followed by bacterial display screening using anchored periplasmic expression (APEx) were used to generate a number of higher-affinity variants of the severe acute respiratory syndrome coronavirus (SARS-CoV)-neutralizing antibody 80R with equilibrium dissociation constants (KD) as low as 37 pM, a >270-fold improvement relative to that of the parental 80R single-chain variable fragment (scFv). As expected, antigen affinity was shown to correlate directly with neutralization potency toward the icUrbani strain of SARS-CoV. Additionally, the highest-affinity antibody fragment displayed 10-fold-increased broad neutralization in vitro and completely protected against several SARS-CoV strains containing substitutions associated with antibody escape. Importantly, higher affinity also led to the suppression of viral escape mutants in vitro. Escape from the highest-affinity variant required reduced selective pressure and multiple substitutions in the binding epitope. Collectively, these results support the hypothesis that engineered antibodies with picomolar dissociation constants for a neutralizing epitope can confer escape-resistant protection

Extremal Transitions in Heterotic String Theory

In this paper we study extremal transitions between heterotic string compactifications, i.e., transitions between pairs (M,V) where M is a Calabi-Yau manifold and V a gauge bundle. Bundle transitions are described using language recently espoused by Friedman, Morgan, Witten. In addition, partly as a check on our methods, we also study how small instantons are described in the same language, and also describe the sheaves corresponding to small instantons.Comment: 26 pages, LaTex, 3 figures, references adde

Synaptotagmin-1 membrane binding is driven by the C2B domain and assisted cooperatively by the C2A domain

Synaptotagmin interaction with anionic lipid (phosphatidylserine/phosphatidylinositol) containing membranes, both in the absence and presence of calcium ions (Ca2+), is critical to its central role in orchestrating neurotransmitter release. The molecular surfaces involved, namely the conserved polylysine motif in the C2B domain and Ca2+-binding aliphatic loops on both C2A and C2B domains, are known. Here we use surface force apparatus combined with systematic mutational analysis of the functional surfaces to directly measure Syt1-membrane interaction and fully map the site-binding energetics of Syt1 both in the absence and presence of Ca2+. By correlating energetics data with the molecular rearrangements measured during confinement, we find that both C2 domains cooperate in membrane binding, with the C2B domain functioning as the main energetic driver, and the C2A domain acting as a facilitator.Fil: Gruget, Clémence. Ecole Normale Supérieure; FranciaFil: Bello, Oscar Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Coleman, Jeff. University of Yale. School of Medicine; Estados UnidosFil: Krishnakumar, Shyam S.. University of Yale. School of Medicine; Estados UnidosFil: Perez, Eric. Ecole Normale Supérieure; FranciaFil: Rothman, James E.. University of Yale. School of Medicine; Estados UnidosFil: Pincet, Frederic. Ecole Normale Supérieure; Francia. University of Yale. School of Medicine; Estados UnidosFil: Donaldson, Stephen H.. Ecole Normale Supérieure; Franci

Emergence of New Pandemic GII.4 Sydney Norovirus Strain Correlates With Escape From Herd Immunity

Background. GII.4 noroviruses are a significant source of acute gastroenteritis worldwide, causing the majority of human norovirus outbreaks. Evolution of the GII.4 major capsid protein occurs rapidly, resulting in the emergence of new strains that produce successive waves of pandemic disease. A new pandemic isolate, GII.4 2012 Sydney, largely replaced previously circulating strains in late 2012. We compare the antigenic properties of GII.4 2012 Sydney with previously circulating strains. Methods. To determine whether GII.4-2012 Sydney is antigenically different from recently circulating strains GII.4-2006 Minerva and GII.4-2009 New Orleans in previously identified blockade epitopes, we compared reactivity and blockade profiles of GII.4-2006, GII.4-2009, and GII.4-2012 virus-like particles in surrogate neutralization/blockade assays using monoclonal antibodies and human polyclonal sera. Results. Using monoclonal antibodies that map to known blockade epitopes in GII.4-2006 and GII.4-2009 and human outbreak polyclonal sera, we demonstrate either complete loss or significantly reduced reactivity and blockade of GII.4.2012 compared to GII.4-2006 and GII.4-2009. Conclusions. GII.4-2012 Sydney is antigenically different from GII.4-2006 Minerva and GII.4-2009 New Orleans in at least 2 key blockade epitopes. Viral evolution in key potential neutralization epitopes likely allowed GII.4-2012 to escape from human herd immunity and emerge as the new predominant strai

Mindfulness-Oriented Recovery Enhancement vs Supportive Group Therapy for Co-occurring Opioid Misuse and Chronic Pain in Primary Care: A Randomized Clinical Trial

Importance: Successful treatment of opioid misuse among people with chronic pain has proven elusive. Guidelines recommend nonopioid therapies, but the efficacy of mindfulness-based interventions for opioid misuse is uncertain. Objective: To evaluate the efficacy of Mindfulness-Oriented Recovery Enhancement (MORE) for the reduction of opioid misuse and chronic pain. Design, Setting, and Participants: This interviewer-blinded randomized clinical trial enrolled patients from primary care clinics in Utah between January 4, 2016, and January 16, 2020. The study included 250 adults with chronic pain receiving long-term opioid therapy who were misusing opioid medications. Interventions: Treatment with MORE (comprising training in mindfulness, reappraisal, and savoring positive experiences) or supportive group psychotherapy (control condition) across 8 weekly 2-hour group sessions. Main Outcomes and Measures: Primary outcomes were (1) opioid misuse assessed by the Drug Misuse Index (self-report, interview, and urine screen) and (2) pain severity and pain-related functional interference, assessed by subscale scores on the Brief Pain Inventory through 9 months of follow-up. Secondary outcomes were opioid dose, emotional distress, and ecological momentary assessments of opioid craving. The minimum intervention dose was defined as 4 or more completed sessions of MORE or supportive group psychotherapy. Results: Among 250 participants (159 women [63.6%]; mean [SD] age, 51.8 [11.9] years), 129 were randomized to the MORE group and 121 to the supportive psychotherapy group. Overall, 17 participants (6.8%) were Hispanic or Latino, 218 (87.2%) were White, and 15 (6.0%) were of other races and/or ethnicities (2 American Indian, 3 Asian, 1 Black, 2 Pacific Islander, and 7 did not specify). At baseline, the mean duration of pain was 14.7 years (range, 1-60 years), and the mean (SD) morphine-equivalent opioid dose was 101.0 (266.3) mg (IQR, 16.0-90.0 mg). A total of 203 participants (81.2%) received the minimum intervention dose (mean [SD], 5.7 [2.2] sessions); at 9 months, 92 of 250 participants (36.8%) discontinued the study. The overall odds ratio for reduction in opioid misuse through the 9-month follow-up period in the MORE group compared with the supportive psychotherapy group was 2.06 (95% CI, 1.17-3.61; P = .01). At 9 months, 36 of 80 participants (45.0%) in the MORE group were no longer misusing opioids compared with 19 of 78 participants (24.4%) in the supportive psychotherapy group. Mixed models demonstrated that MORE was superior to supportive psychotherapy through 9 months of follow-up for pain severity (between-group effect: 0.49; 95% CI, 0.17-0.81; P = .003) and pain-related functional interference (between-group effect: 1.07; 95% CI, 0.64-1.50; P < .001). Participants in the MORE group reduced their opioid dose to a greater extent than those in the supportive psychotherapy group. The MORE group also had lower emotional distress and opioid craving. Conclusions and Relevance: In this randomized clinical trial, among adult participants in a primary care setting, the MORE intervention led to sustained improvements in opioid misuse and chronic pain symptoms and reductions in opioid dosing, emotional distress, and opioid craving compared with supportive group psychotherapy. Despite attrition caused by the COVID-19 pandemic and the vulnerability of the sample, MORE appeared to be efficacious for reducing opioid misuse among adults with chronic pain. Trial Registration: ClinicalTrials.gov Identifier: NCT0260253