bluuebunny/crossref_metadata_2025 huggingface dataset:
The complexity of human cooperation under indirect reciprocity
Authors: Santos Fernando P. , Pacheco Jorge M. , Santos Francisco C.
Published: October 2021

Indirect reciprocity (IR) is a key mechanism to understand cooperation among unrelated individuals. It involves reputations and complex information processing, arising from social interactions. By helping someone, individuals may improve their reputation, which may be shared in a population and change the predisposition of others to reciprocate in the future. The reputation of individuals depends, in turn, on social norms that define a good or bad action, offering a computational and mathematical appealing way of studying the evolution of moral systems. Over the years, theoretical and empirical research has unveiled many features of cooperation under IR, exploring norms with varying degrees of complexity and information requirements. Recent results suggest that costly reputation spread, interaction observability and empathy are determinants of cooperation under IR. Importantly, such characteristics probably impact the level of complexity and information requirements for IR to sustain cooperation. In this review, we present and discuss those recent results. We provide a synthesis of theoretical models and discuss previous conclusions through the lens of evolutionary game theory and cognitive complexity. We highlight open questions and suggest future research in this domain.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Cooperating to show that you care: costly helping as an honest signal of fitness interdependence
Authors: Barclay Pat , Bliege Bird Rebecca , Roberts Gilbert , Számadó Szabolcs
Published: October 2021

Social organisms often need to know how much to trust others to cooperate. Organisms can expect cooperation from another organism that depends on them (i.e. stake or fitness interdependence), but how do individuals assess fitness interdependence? Here, we extend fitness interdependence into a signalling context: costly helping behaviour can honestly signal one's stake in others, such that those who help are trusted more. We present a mathematical model in which agents help others based on their stake in the recipient's welfare, and recipients use that information to assess whom to trust. At equilibrium, helping is a costly signal of stake: helping is worthwhile for those who value the recipient (and thus will repay any trust), but is not worthwhile for those who do not value the recipient (and thus will betray the trust). Recipients demand signals when they value the signallers less and when the cost of betrayed trust is higher; signal costs are higher when signallers have more incentive to defect. Signalling systems are more likely when the trust games resemble Prisoner's Dilemmas, Stag Hunts or Harmony Games, and are less likely in Snowdrift Games. Furthermore, we find that honest signals need not benefit recipients and can even occur between hostile parties. By signalling their interdependence, organisms benefit from increased trust, even when no future interactions will occur.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Reputation and punishment sustain cooperation in the optional public goods game
Authors: Podder Shirsendu , Righi Simone , Pancotto Francesca
Published: October 2021

Cooperative behaviour has been extensively studied as a choice between cooperation and defection. However, the possibility to not participate is also frequently available. This type of problem can be studied through the optional public goods game. The introduction of the ‘Loner’ strategy' allows players to withdraw from the game, which leads to a cooperator–defector–loner cycle. While pro-social punishment can help increase cooperation, anti-social punishment—where defectors punish cooperators—causes its downfall in both experimental and theoretical studies. In this paper, we introduce social norms that allow agents to condition their behaviour to the reputation of their peers. We benchmark this with respect both to the standard optional public goods game and to the variant where all types of punishment are allowed. We find that a social norm imposing a more moderate reputational penalty for opting out than for defecting increases cooperation. When, besides reputation, punishment is also possible, the two mechanisms work synergically under all social norms that do not assign to loners a strictly worse reputation than to defectors. Under this latter set-up, the high levels of cooperation are sustained by conditional strategies, which largely reduce the use of pro-social punishment and almost completely eliminate anti-social punishment.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Parochial cooperation and the emergence of signalling norms
Authors: Przepiorka Wojtek , Diekmann Andreas
Published: October 2021

Why do people adorn themselves with elaborate body piercings or tattoos, wear obstructing garbs, engage in life-threatening competitions and other wasteful and harmful but socially stipulated practices? Norms of cooperation and coordination, which promote the efficient attainment of collective benefits, can be explained by theories of collective action. However, social norms prescribing wasteful and harmful behaviours have eluded such explanations. We argue that signalling theory constitutes the basis for the understanding of the emergence of such norms, which we call signalling norms. Signalling norms emerge as a result of the uncertainty about who is a friend and who is a foe. The need to overcome this uncertainty arises when different groups compete for scarce resources and individuals must be able to identify, trust and cooperate with their fellow group members. After reviewing the mechanisms that explain the emergence of cooperation and coordination norms, we introduce the notion of signalling norms as markers of group distinction. We argue that adherence to signalling norms constitutes a commitment promoting parochial cooperation rather than a quality-revealing signal facilitating partner choice. We formalize our argument in a game-theoretic model that allows us to specify the boundary conditions for the emergence of signalling norms. Our paper concludes with a discussion of potential applications of our model and a comparison of signalling norms with related concepts.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Reputation and socio-ecology in humans
Authors: Romano A. , Giardini F. , Columbus S. , de Kwaadsteniet E. W. , Kisfalusi D. , Triki Z. , Snijders C. , Hagel K.
Published: October 2021

Reputation is a fundamental feature of human sociality as it sustains cooperative relationships among unrelated individuals. Research from various disciplines provides insights on how individuals form impressions of others, condition their behaviours based on the reputation of their interacting partners and spread or learn such reputations. However, past research has often neglected the socio-ecological conditions that can shape reputation systems and their effect on cooperation. Here, we outline how social environments, cultural values and institutions come to play a crucial role in how people navigate reputation systems. Moreover, we illustrate how these socio-ecological dimensions affect the interdependence underlying social interactions (e.g. potential recipients of reputational benefits, degree of dependence) and the extent to which reputation systems promote cooperation. To do so, we review the interdisciplinary literature that illustrates how reputation systems are shaped by the variation of prominent ecological features. Finally, we discuss the implications of a socio-ecological approach to the study of reputation and outline potential avenues for future research.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
The content and structure of reputation domains across human societies: a view from the evolutionary social sciences
Authors: Garfield Zachary H. , Schacht Ryan , Post Emily R. , Ingram Dominique , Uehling Andrea , Macfarlan Shane J.
Published: October 2021

Reputations are an essential feature of human sociality and the evolution of cooperation and group living. Much scholarship has focused on reputations, yet typically on a narrow range of domains (e.g. prosociality and aggressiveness), usually in isolation. Humans can develop reputations, however, from any collective information. We conducted exploratory analyses on the content, distribution and structure of reputation domain diversity across cultures, using the Human Relations Area Files ethnographic database. After coding ethnographic texts on reputations from 153 cultures, we used hierarchical modelling, cluster analysis and text analysis to provide an empirical view of reputation domains across societies. Findings suggest: (i) reputational domains vary cross-culturally, yet reputations for cultural conformity, prosociality, social status and neural capital are widespread; (ii) reputation domains are more variable for males than females; and (iii) particular reputation domains are interrelated, demonstrating a structure consistent with dimensions of human uniqueness. We label these features:cultural group unity,dominance,neural capital,sexuality,social and material successandsupernatural healing. We highlight the need for future research on the evolution of cooperation and human sociality to consider a wider range of reputation domains, as well as their social, ecological and gender-specific variability.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Networks of reliable reputations and cooperation: a review
Authors: Takács Károly , Gross Jörg , Testori Martina , Letina Srebrenka , Kenny Adam R. , Power Eleanor A. , Wittek Rafael P. M.
Published: October 2021

Reputation has been shown to provide an informal solution to the problem of cooperation in human societies. After reviewing models that connect reputations and cooperation, we address how reputation results from information exchange embedded in a social network that changes endogenously itself. Theoretical studies highlight that network topologies have different effects on the extent of cooperation, since they can foster or hinder the flow of reputational information. Subsequently, we review models and empirical studies that intend to grasp the coevolution of reputations, cooperation and social networks. We identify open questions in the literature concerning how networks affect the accuracy of reputations, the honesty of shared information and the spread of reputational information. Certain network topologies may facilitate biased beliefs and intergroup competition or in-group identity formation that could lead to high cooperation within but conflicts between different subgroups of a network. Our review covers theoretical, experimental and field studies across various disciplines that target these questions and could explain how the dynamics of interactions and reputations help or prevent the establishment and sustainability of cooperation in small- and large-scale societies.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
When does reputation lie? Dynamic feedbacks between costly signals, social capital and social prominence
Authors: Dumas Marion , Barker Jessica L. , Power Eleanor A.
Published: October 2021

Performing a dramatic act of religious devotion, creating an art exhibit, or releasing a new product are all examples of public acts that signal quality and contribute to building a reputation. Signalling theory predicts that these public displays can reliably reveal quality. However, data from ethnographic work in South India suggests that more prominent individuals gain more from reputation-building religious acts than more marginalized individuals. To understand this phenomenon, we extend signalling theory to include variation in people’s social prominence or social capital, first with an analytical model and then with an agent-based model. We consider two ways in which social prominence/capital may alter signalling: (i) it impacts observers’ priors, and (ii) it alters the signallers’ pay-offs. These two mechanisms can result in both a ‘reputational shield,’ where low quality individuals are able to ‘pass’ as high quality thanks to their greater social prominence/capital, and a ‘reputational poverty trap,’ where high quality individuals are unable to improve their standing owing to a lack of social prominence/capital. These findings bridge the signalling theory tradition prominent in behavioural ecology, anthropology and economics with the work on status hierarchies in sociology, and shed light on the complex ways in which individuals make inferences about others.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
The effects of reputation on inequality in network cooperation games
Authors: Tsvetkova Milena
Published: October 2021

In the last several decades, ample evidence from across evolutionary biology, behavioural economics and econophysics has solidified our knowledge that reputation can promote cooperation across different contexts and environments. Higher levels of cooperation entail higher final payoffs on average, but how are these payoffs distributed among individuals? This study investigates how public and objective reputational information affects payoff inequality in repeated social dilemma interactions in large groups. I consider two aspects of inequality: excessive dispersion of final payoffs and diminished correspondence between final payoff and cooperative behaviour. I use a simple heuristics-based agent model to demonstrate that reputational information does not always increase the dispersion of final payoffs in strategically updated networks, and actually decreases it in randomly rewired networks. More importantly, reputational information almost always improves the correspondence between final payoffs and cooperative behaviour. I analyse empirical data from nine experiments of the repeated Trust, Helping, Prisoner's Dilemma and Public Good games in networks of ten or more individuals to provide partial support for the predictions. Our research suggests that reputational information not only improves cooperation but may also reduce inequality.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling'.
Honesty and dishonesty in gossip strategies: a fitness interdependence analysis
Authors: Wu Junhui , Számadó Szabolcs , Barclay Pat , Beersma Bianca , Dores Cruz Terence D. , Iacono Sergio Lo , Nieper Annika S. , Peters Kim , Przepiorka Wojtek , Tiokhin Leo , Van Lange Paul A. M.
Published: October 2021

Gossip, or sharing information about absent others, has been identified as an effective solution to free rider problems in situations with conflicting interests. Yet, the information transmitted via gossip can be biased, because gossipers may send dishonest information about others for personal gains. Such dishonest gossip makes reputation-based cooperation more difficult to evolve. But when are people likely to share honest or dishonest gossip? We build formal models to provide the theoretical foundation for individuals' gossip strategies, taking into account the gossiper's fitness interdependence with the receiver and the target. Our models across four different games suggest a very simple rule: when there is a perfect match (mismatch) between fitness interdependence and the effect of honest gossip, the gossiper should always be honest (dishonest); however, in the case of a partial match, the gossiper should make a choice based on their fitness interdependence with the receiver and the target and the marginal cost/benefit in terms of pay-off differences caused by possible choices of the receiver and the target in the game. Moreover, gossipers can use this simple rule to make optimal decisions even under noise. We discuss empirical examples that support the predictions of our model and potential extensions.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Gossip and reputation in everyday life
Authors: Dores Cruz Terence D. , Thielmann Isabel , Columbus Simon , Molho Catherine , Wu Junhui , Righetti Francesca , de Vries Reinout E. , Koutsoumpis Antonis , van Lange Paul A. M. , Beersma Bianca , Balliet Daniel
Published: October 2021

Gossip—a sender communicating to a receiver about an absent third party—is hypothesized to impact reputation formation, partner selection, and cooperation. Laboratory experiments have found that people gossip about others' cooperativeness and that they use gossip to condition their cooperation. Here, we move beyond the laboratory and test several predictions from theories of indirect reciprocity and reputation-based partner selection about the content of everyday gossip and how people use it to update the reputation of others in their social network. In a Dutch community sample (N= 309), we sampled daily events in which people either sent or received gossip about a target over 10 days (ngossip= 5284). Gossip senders frequently shared information about targets’ cooperativeness and did so in ways that minimize potential retaliation from targets. Receivers overwhelmingly believed gossip to be true and updated their evaluation of targets based on gossip. In turn, a positive shift in the evaluation of a target was associated with higher intentions to help them in future interactions, and with lower intentions to avoid them in the future. Thus, gossip is used in daily life to impact and update reputations in a way that enables partner selection and indirect reciprocity.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Evaluating mechanisms that could support credible reputations and cooperation: cross-checking and social bonding
Authors: Samu Flóra , Takács Károly
Published: October 2021

Gossip is believed to be an informal device that alleviates the problem of cooperation in humans. Communication about previous acts and passing on reputational information could be valuable for conditional action in cooperation problems and pose a punishment threat to defectors. It is an open question, however, what kind of mechanisms can make gossip honest and credible and reputational information reliable, especially if intense competition for reputations does not exclusively dictate passing on honest information. We propose two mechanisms that could support the honesty and credibility of gossip under such a conflict of interest. One is the possibility of voluntary checks of received evaluative information from different sources and the other is social bonding between the sender and the receiver. We tested the efficiency of cross-checking and social bonding in a laboratory experiment where subjects played the Prisoner's Dilemma with gossip interactions. Although individuals had confidence in gossip in both conditions, we found that, overall, neither the opportunities for cross-checking nor bonding were able to maintain cooperation. Meanwhile, strong competition for reputation increased cooperation when individuals' payoffs depended greatly on their position relative to their rivals. Our results suggest that intense competition for reputation facilitates gossip functioning as an informal device promoting cooperation.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Gossip and competitive altruism support cooperation in a Public Good game
Authors: Giardini Francesca , Vilone Daniele , Sánchez Angel , Antonioni Alberto
Published: October 2021

When there is an opportunity to gain a positive reputation, individuals are more willing to sacrifice their immediate self-interest. Partner choice creates opportunities for competitive altruism, i.e. individuals compete to be regarded as more generous and to be chosen for future partnerships. Tests of the competitive altruism hypothesis have focused so far on reputation based on direct observation, whereas the role of gossip has not been theoretically and empirically addressed. Partner choice can create an incentive to cooperate and to send truthful messages, but it can also work in the opposite direction. In order to understand the consequences of partner choice on cooperation and gossip, we designed an experimental study in which participants played a sequence of Public Goods games and gossip rounds. In our two treatments, we observed that cooperation increased when there was an opportunity to be selected, but also that cooperators sent more honest messages than defectors, and that this strategy was prevalent in the treatment in which inter-group competition was implemented. We also found evidence that participants detached themselves from the information more often when lying. Taken together, our study fills a theoretical and empirical gap by showing that partner choice increases both cooperation and honesty of gossip.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Is it costly to deceive? People are adept at detecting gossipers' lies but may not reward honesty
Authors: Fonseca Miguel A. , Peters Kim
Published: October 2021

The possibility that gossipers may share dishonest reputational information is a key challenge to claims that gossip can shore up cooperation in social groups. It has been suggested that imposing social costs on dishonest gossipers should increase the honesty of these reputational signals. However, at present, there is little evidence of people's willingness to impose costs on dishonest gossipers; there is also little evidence of their ability to detect gossipers' lies in the first place. This paper aims to shed light on people's abilities to detect dishonest gossip and their treatment of those who share it. To do this, we report the results of two trust game studies using the strategy method (study 1) and repeated interactions in the laboratory (study 2). We show that in an environment where gossipers tell spontaneous lies people are more inclined to believe honest than dishonest gossip. We also show that people are more likely to treat favourably gossipers they believe to be honest, but that this does not always result in more favourable treatment for gossipers who were actually honest. We discuss the implications for the potential utility of social sanctions as a tool for securing honesty.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Competitive gossip: the impact of domain, resource value, resource scarcity and coalitions
Authors: Hess Nicole H. , Hagen Edward H.
Published: October 2021

Those with better reputations often obtain more resources than those with poorer reputations. Consequently, gossip might be an evolved strategy to compete for valuable and scarce material and social resources. Influenced by models of non-human primate competition, we test the hypotheses that gossip: (i) targets aspects of reputation relevant to the domain in which the competition is occurring, (ii) increases when contested resources are more valuable, and (iii) increases when resources are scarcer. We then test hypotheses derived from informational warfare theory, which proposes that coalitions strategically collect, analyse and disseminate gossip. Specifically, we test whether: (iv) coalitions deter negative gossip, and (v) whether they increase expectations of reputational harm to competitors. Using experimental methods in a Mechanical Turk sample (n= 600), and survey and ego network analysis methods in a sample of California sorority women (n= 74), we found that gossip content is specific to the context of the competition; that more valuable and scarcer resources cause gossip, particularly negative gossip, to intensify; and that allies deter negative gossip and increase expectations of reputational harm to an adversary. These results support social competition theories of gossip.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.
Aquibacillus kalidii sp. nov., an indole acetic acid-producing endophyte from a shoot of Kalidium cuspidatum, and reclassification of Virgibacillus campisalis Lee et al. 2012 as a later heterotypic synonym of Virgibacillus alimentarius Kim et al. 2011
Authors: Wang Hai-Tao , Xu Lian , Sun Ji-Quan
Published: October 2021

A Gram-stain-positive, strictly aerobic, motile, endospore-forming, milk-white, indole acetic acid-producing, rod-shaped bacterial strain, designated as HU2P27T, was isolated from a shoot of Kalidium cuspidatum collected in Tumd Right Banner, Inner Mongolia, PR China. Strain grew at 10–40 °C (optimum, 30 °C), at pH 6.0–9.0 (optimum, pH 7.0) and with 0–14.0 % NaCl (optimum, 5.0–8.0 %). The strain tested positive for oxidase, catalase and nitrate reductase. The phylogenetic trees based on the 16S rRNA gene sequence and the core genome both showed that strain HU2P27T clustered with

Aquibacillus koreensis

BH30097T, sharing 97.7 % and <97.0 % of 16S rRNA gene similarity with

A. koreensis

BH30097T and any other type strain. Strain HU2P27T contained MK-7 as the major respiratory quinone. Its major fatty acids were anteiso-C15 : 0 and iso-C15 : 0, and the major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and four unidentified phospholipids. The genomic DNA G+C content was 36.0 mol%. The average nucleotide identity, amino acid identity and digital DNA–DNA hybridization values of strain HU2P27T with

A. koreensis

BH30097T were 71.7, 69.2 and 19.4%, respectively. The phylogenetic, physiological and phenotypic results allowed the discrimination of strain HU2P27T from its phylogenetic relatives. The name Aquibacillus kalidii sp. nov. is therefore proposed. The type strain is strain HU2P27T (=CGMCC 1.18646T=KCTC 43248T). Based on the results of 16S rRNA gene and genome analyses, we propose the reclassification of

Virgibacillus campisalis

Lee et al. 2012 as a later heterotypic synonym of

Virgibacillus alimentarius

Kim et al. 2011.
Proposal for the creation of a new genus Musicola gen. nov., reclassification of Dickeya paradisiaca (Samson et al. 2005) as Musicola paradisiaca comb. nov. and description of a new species Musicola keenii sp. nov.
Authors: Hugouvieux-Cotte-Pattat Nicole , des-Combes Cécile Jacot , Briolay Jérôme , Pritchard Leighton
Published: October 2021

The

Pectobacteriaceae

family of important plant pathogens includes the genus

Dickeya

. There are currently 12 described species of

Dickeya

, although some are poorly characterized at the genomic level. Only two genomes of

Dickeya paradisiaca

, the type strain CFBP 4178T and strain Ech703, have previously been sequenced. Members of this species are mostly of tropical or subtropical origin. During an investigation of strains present in our laboratory collection we sequenced the atypical strain A3967, registered as CFBP 722, isolated from Solanum lycopersicum (tomato) in the South of France in 1965. The genome of strain A3967 shares digital DNA–DNA hybridization and average nucleotide identity (ANI) values of 68 and 96 %, respectively, with the

D. paradisiaca

type strain CFBP 4178T. However, ANI analysis showed that

D. paradisiaca

strains are significantly dissimilar to the other

Dickeya

species, such that less than one third of their genomes align to any other

Dickeya

genome. On phenotypic, phylogenetic and genomic grounds, we propose a reassignment of

D. paradisiaca

to the genus level, for which we propose the name Musicola gen. nov., with Musicola paradisiaca as the type species and CFBP 4178T (NCPPB 2511T) as the type strain. Phenotypic analysis showed differences between strain A3967T and CFBP 4178T, such as for the assimilation of melibiose, raffinose and myo-inositol. These results support the description of two novel species, namely Musicola paradisiaca comb. nov. and Musicola keenii sp. nov., with CFBP 4178T (NCPPB 2511T=LMG 2542T) and A3967T (CFBP 8732T=LMG 31880T) as the type strains, respectively.
The MpsB protein contributes to both the toxicity and immune evasion capacity of Staphylococcus aureus
Authors: Douglas Edward J. A. , Duggan Seána , Brignoli Tarcisio , Massey Ruth C.
Published: October 2021

Understanding the role specific bacterial factors play in the development of severe disease in humans is critical if new approaches to tackle such infections are to be developed. In this study we focus on genes we have found to be associated with patient outcome following bacteraemia caused by the major human pathogen

Staphylococcus aureus

. By examining the contribution these genes make to the ability of the bacteria to survive exposure to the antibacterial factors found in serum, we identify three novel serum resistance-associated genes, mdeA, mpsB and yycH. Detailed analysis of an MpsB mutant supports its previous association with the slow growing small colony variant (SCV) phenotype of

S. aureus

, and we demonstrate that the effect this mutation has on membrane potential prevents the activation of the Agr quorum sensing system, and as a consequence the mutant bacteria do not produce cytolytic toxins. Given the importance of both toxin production and immune evasion for the ability of

S. aureus

to cause disease, we believe that these findings explain the role of the mpsB gene as a mortality-associated locus during human disease.
Seroprevalence of COVID-19 in Palestine in 2020
Authors: Rayan I , Qaddomi SE , Najjar O , Abbas S , Mousa K , Iraqi L , Abdelkreem Aly E , Abu Khader K , Barakat A , Salman R
Published: October 2021

COVID-19 affected different countries in different ways. Palestine had recorded over 140,000 cases by the end of 2020. The WHO/PNIPH, WHO/EMRO, and the Palestinian MoH carried out a serological survey in Palestine in order to estimate the actual number of COVID-19 infections up to the end of December 2020. A sample stratified by region, district, residence area (urban, rural, and refugee camp), and accounting for gender, was taken from Gaza and the West Bank. Data from participants were also collected, including demographic, socio-economic, and health conditions. The results show that 39% of the Palestinian population (38% of the West Bank and 40% of Gaza) had been infected with COVID-19 by the end of December, almost 10 times the number detected by targeted Rt-PCR testing. Several factors were calculated to be significant such as diabetes, smoking, gender, age, and residence.

Summary of findings

The following table is a summary of all findings presented in this report. The P values in green are below 0.05, which makes the result statistically significant; red is not statistically significant. In binary comparisons (when comparing two numbers), the odds were calculated, meaning how much more likely the presence of seropositivity is if the condition is satisfied. For example, those who were previously diagnosed as COVID-19 positive using Rt PCR were 2.5 times as likely to be seropositive than those who were not diagnosed.
Comparison of antibody immune responses between BNT162b2 and mRNA-1273 SARS-CoV-2 vaccines in naïve and previously infected individuals
Authors: Al-Sadeq Duaa W. , Shurrab Farah M. , Ismail Ahmed , Amanullah Fathima Humaira , Thomas Swapna , Aldewik Nader , Yassine Hadi M. , Abdul Rahim Hanan F. , Abu-Raddad Laith , Nasrallah Gheyath K.
Published: October 2021

Two mRNA vaccines, Pfizer-BNT162b2 and Moderna-mRNA-1273, were granted the US Food and Drug Administration Emergency Use Authorization for preventing COVID-19. However, little is known about the difference in antibody responses induced by the two mRNA vaccines in naïve and individuals with a previous history of infections (PI group). Therefore, we investigated the levels of anti-S-RBD total antibodies (IgM, IgA, and IgG), anti-S-RBD IgG, and anti-S-RBD IgA in these two groups 1-13 (median=6) weeks following administration of two doses of mRNA-1273 or BNT162b2 vaccines. Results showed that in naïve-vaccinated group, the mRNA-1327 vaccine induces significantly higher levels of S-RBD total antibodies (3.5-fold; p<0.001), S-RBD IgG (2-fold-p<0.01), and S-IgA (2.1-fold, p<0.001) than the BNT162b2 vaccine. In the PI-vaccinated group, both vaccines produce significantly higher S-RBD total antibodies level than those of the naïve-vaccinated group. The PI group produced a higher level of S-RBD IgG than the naïve-BNT162b2 (p=0.05) but not more than the naïve-mRNA-1273 (p=0.9) group. Interestingly, the PI-vaccinated group produced a comparable level of IgA ratio to the naïve-mRNA-1273 group but significantly higher than the naïve-BNT162b2 group (1.6-fold, p<0.001). Our results showed that the mRNA-1327 vaccine is more immunogenic and induces a greater antibody response than the BNT162b2 vaccine.
Seropositivity to Nucleoprotein to detect SARS-CoV-2 infections: a tool to detect breakthrough infections after COVID-19 vaccination
Authors: van den Hoogen Lotus L. , Smits Gaby , van Hagen Cheyenne C.E. , Wong Denise , Vos Eric R.A. , van Boven Michiel , de Melker Hester E. , van Vliet Jeffrey , Kuijer Marjan , Woudstra Linde , Wijmenga-Monsuur Alienke J. , GeurtsvanKessel Corine H. , Stoof Susanne P. , Reukers Daphne , Wijsman Lisa A. , Meijer Adam , Reusken Chantal B.E.M. , Rots Nynke Y. , van der Klis Fiona R.M. , van Binnendijk Robert S. , Hartog Gerco den
Published: October 2021

Background

With COVID-19 vaccine roll-out ongoing in many countries globally, monitoring of breakthrough infections is of great importance. Antibodies persist in the blood after a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Since COVID-19 vaccines induce immune response to the Spike protein of the virus, which is the main serosurveillance target to date, alternative targets should be explored to distinguish infection from vaccination.

Methods

Multiplex immunoassay data from 1,513 SARS-CoV-2 RT-qPCR-tested individuals (352 positive and 1,161 negative) with a primary infection and no vaccination history were used to determine the accuracy of Nucleoprotein-specific immunoglobulin G (IgG) in detecting past SARS-CoV-2 infection. We also described Spike S1 and Nucleoprotein-specific IgG responses in 230 COVID-19 vaccinated individuals (Pfizer/BioNTech).

Results

The sensitivity of Nucleoprotein seropositivity was 85% (95% confidence interval: 80-90%) for mild COVID-19 in the first two months following symptom onset. Sensitivity was lower in asymptomatic individuals (67%, 50-81%). Participants who had experienced a SARS-CoV-2 infection up to 11 months preceding vaccination, as assessed by Spike S1 seropositivity or RT-qPCR, produced 2.7-fold higher median levels of IgG to Spike S1 ≥14 days after the first dose as compared to those unexposed to SARS-CoV-2 at ≥7 days after the second dose (p=0.011). Nucleoprotein-specific IgG concentrations were not affected by vaccination in naïve participants.

Conclusions

Serological responses to Nucleoprotein may prove helpful in identifying SARS-CoV-2 infections after vaccination. Furthermore, it can help interpret IgG to Spike S1 after COVID-19 vaccination as particularly high responses shortly after vaccination could be explained by prior exposure history.
Effectiveness and Safety of MSC Cell Therapies for Hospitalized Patients with COVID-19: A Systematic Review and Meta-analysis
Authors: Qu Wenchun , Wang Zhen , Engelberg-Cook Erica , Siddik Abu Bakar , Bu Guojun , Allickson Julie G. , Kubrova Eva , Caplan Arnold I. , Hare Joshua M. , Ricordi Camillo , Pepine Carl J. , Kurtzberg Joanne , Pascual Jorge M. , Mallea Jorge M. , Rodriguez Ricardo L. , Nayfeh Tarek , Saadi Samer , Richards Elaine M. , March Keith , Sanfilippo Fred P.
Published: October 2021

MSC (a.k.a. mesenchymal stem cell or medicinal signaling cell) cell therapies have shown promise in decreasing mortality in ARDS and suggest benefits in treatment of COVID-19 related ARDS. We performed a meta-analysis of published trials assessing the effectiveness and adverse events (AE) of MSC cell therapy in individuals hospitalized for COVID-19. Systematic searches were performed in multiple databases through April 8th, 2021. Reports in all languages including randomized clinical trials (RCTs), comparative observational studies, and case series/case reports were included. Random effects model was used to pool outcomes from RCTs and comparative observational studies. Outcome measures included all-cause mortality, serious adverse events (SAEs), AEs, pulmonary function, laboratory and imaging findings. A total of 413 patients were identified from 25 studies, which included 8 controlled trials (3 RCTs), 5 comparative observational studies, (n=300) and 17 case-series/case reports (n=113). The patients age was 60.5 years (mean), 33.7% were women. When compared with the control group, MSC cell therapy was associated with reduction in all-cause mortality (RR=0.31, 95% CI: 0.12 to 0.75, I2=0.0%; 3 RCTs and 5 comparative observational studies, 300 patients), reduction in SAEs (IRR=0.36, 95% CI: 0.14 to 0.90, I2=0.0%; 3 RCTs and 2 comparative studies, n=219), no significant difference in AE rate. A sub-group with pulmonary function studies suggested improvement in patients receiving MSC. These findings support the potential for MSC cell therapy to decrease all-cause mortality, reduce SAEs, and improve pulmonary function compared to conventional care. Large scale double-blinded, well-powered RCTs should be conducted to further explore these results.
Machine learning algorithm to perform ASA Physical Status Classification
Authors: Pozhitkov Alexander , Seth Naini , Kidambi Trilokesh D. , Raytis John , Achuthan Srisairam , Lew Michael W.
Published: October 2021

Background

The American Society of Anesthesiologists (ASA) Physical Status Classification System defines peri-operative patient scores as 1 (healthy) thru 6 (brain dead). The scoring is used by the anesthesiologists to classify surgical patients based on co-morbidities and various clinical characteristics. The classification is always done by an anesthesiologist prior operation. There is a variability in scoring stemming from individual experiences / biases of the scoring anesthesiologists, which impacts prediction of operating times, length of stay in the hospital, necessity of blood transfusion, etc. In addition, the score affects anesthesia coding and billing. It is critical to remove subjectivity from the process to achieve reproducible generalizable scoring.

Methods

A machine learning (ML) approach was used to associate assigned ASA scores with peri-operative patients’ clinical characteristics. More than ten ML algorithms were simultaneously trained, validated, and tested with retrospective records. The most accurate algorithm was chosen for a subsequent test on an independent dataset. DataRobot platform was used to run and select the ML algorithms. Manual scoring was also performed by one anesthesiologist. Intra-class correlation coefficient (ICC) was calculated to assess the consistency of scoring

Results

Records of 19,095 procedures corresponding to 12,064 patients with assigned ASA scores by 17 City of Hope anesthesiologists were used to train a number of ML algorithms (DataRobot platform). The most accurate algorithm was tested with independent records of 2325 procedures corresponding to 1999 patients. In addition, 86 patients from the same dataset were scored manually. The following ICC values were computed: COH anesthesiologists vs. ML – 0.427 (fair); manual vs. ML – 0.523 (fair-to-good); manual vs. COH anesthesiologists – 0.334 (poor).

Conclusions

We have shown the feasibility of using ML for assessing the ASA score. In principle, a group of experts (i.e. physicians, institutions, etc.) can train the ML algorithm such that individual experiences and biases would cancel each leaving the objective ASA score intact. As more data are being collected, a valid foundation for refinement to the ML will emerge.
Analytical performance of eleven SARS-CoV-2 antigen-detecting rapid tests for Delta variant
Authors: Bekliz Meriem , Adea Kenneth , Essaidi-Laziosi Manel , Escadafal Camille , Sacks Jilian A , Kaiser Laurent , Eckerle Isabella
Published: October 2021

Global concerns arose as the emerged and rapidly spreading SARS-CoV-2 Delta variant. To date, few data on routine diagnostic performance for Delta are available. Here, we investigate the analytical performance of eleven commercially available antigen-detecting rapid diagnostic tests (Ag-RDTs) for Delta VOC in comparison with current and earlier VOCs (Alpha, Beta and Gamma) and early pandemic variant using cultured SARS-CoV-2. Comparable sensitivity was observed for Delta for the majority of Ag-RDTs.
Hyaluronidase-1-mediated glycocalyx impairment underlies endothelial abnormalities in polypoidal choroidal vasculopathy
Authors: Wu Kan-Xing , Yeo Natalie Jia Ying , Ng Chun-Yi , Chioh Florence Wen Jing , Qiao Fan , Tian Xianfeng , Binxia Yang , Narayanan Gunaseelan , Tay Hui-Min , Hou Han-Wei , Dunn N Ray , Su Xinyi , Cheung Chui Ming Gemmy , Cheung Christine
Published: October 2021

Background

Polypoidal choroidal vasculopathy (PCV), a subtype of age-related macular degeneration (AMD), is characterized by polyp-like dilatation of blood vessels and turbulent blood flow in the choroid of the eye. Gold standard anti-vascular endothelial growth factor (anti-VEGF) therapy often fails to regress polypoidal lesions in patients. Current animal models have also been hampered by their inability to recapitulate such vascular lesions. These underscore the need to identify VEGF-independent pathways in PCV pathogenesis.

Results

We cultivated blood outgrowth endothelial cells (BOECs) from PCV patients and normal controls to serve as our experimental disease models. When BOECs were exposed to heterogeneous flow, single-cell transcriptomic analysis revealed that PCV BOECs preferentially adopted migratory-angiogenic cell state, while normal BOECs undertook proinflammatory cell state. PCV BOECs also had a repressed protective response to flow stress by demonstrating lower mitochondrial functions. We uncovered that elevated hyaluronidase-1 in PCV BOECs led to increased degradation of hyaluronan, a major component of glycocalyx that interfaces between flow stress and vascular endothelium. Notably, knockdown of hyaluronidase-1 in PCV BOEC improved mechanosensitivity through activation of Krüppel-like factor 2, a flow-responsive transcription factor, which in turn modulated PCV BOEC migration. Barrier permeability due to glycocalyx impairment in PCV BOECs was also reversed by hyaluronidase-1 knockdown. Correspondingly, hyaluronidase-1 was detected in PCV patient vitreous humor and plasma samples.

Conclusions

Hyaluronidase-1 inhibition could be a potential therapeutic modality in preserving glycocalyx integrity and endothelial stability in ocular diseases with vascular origin.
Kinetic Explanations for the Sequence Biases Observed in the Nonenzymatic Copying of RNA Templates
Authors: Ding Dian , Zhou Lijun , Giurgiu Constantin , Szostak Jack W.
Published: October 2021

The identification of nonenzymatic pathways for nucleic acid replication is a key challenge in understanding the origin of life. We have previously shown that nonenzymatic RNA primer extension using 2-aminoimidazole (2AI) activated nucleotides occurs primarily through an imidazolium-bridged dinucleotide intermediate. The reactive nature and preorganized structure of the intermediate increase the efficiency of primer extension but remain insufficient to drive extensive copying of RNA templates containing all four canonical nucleotides. To understand the factors that limit RNA copying, we synthesized all ten 2AI-bridged dinucleotide intermediates and measured the kinetics of primer extension in a model. The affinities of the ten dinucleotides for the primer/template/helper complexes vary by over 7,000-fold, consistent with nearest neighbor energetic predictions. Surprisingly, the reaction rates at saturating intermediate concentrations still vary by over 15-fold, with the most weakly binding dinucleotides exhibiting a lower maximal reaction rate. Certain noncanonical nucleotides can decrease sequence dependent differences in affinity and primer extension rate, while monomers bridged to short oligonucleotides exhibit enhanced binding and reaction rates. We suggest that more uniform binding and reactivity of imidazolium-bridged intermediates may lead to the ability to copy arbitrary template sequences under prebiotically plausible conditions.
Epigenome-wide association study of human frontal cortex identifies differential methylation in Lewy body pathology
Authors: Pihlstrøm Lasse , Shireby Gemma , Geut Hanneke , Henriksen Sandra Pilar , Rozemüller Annemieke J.M. , Tunold Jon-Anders , Hannon Eilis , Francis Paul , Thomas Alan J , Love Seth ,   Netherlands Brain Bank, Mill Jonathan , van de Berg Wilma D.J. , Toft Mathias
Published: October 2021

Parkinson’s disease (PD) and dementia with Lewy bodies (DLB) are closely related progressive disorders with no available causal therapy, neuropathologically characterized by intraneuronal aggregates of misfolded α-synuclein. To explore the role of DNA methylation changes in PD and DLB pathogenesis, we performed an epigenome-wide association study (EWAS) of 322 postmortem frontal cortex samples and replicated results in an independent set of 219 donors. We report novel differentially methylated replicating loci associated with Braak Lewy body stage near SFMBT2, PHYHIP, BRF1/PACS2 and DGKG. The DGKG locus also showed evidence of DNA methylation changes in the earliest, preclinical stage of disease. Differentially methylated probes were independent of known PD genetic risk alleles. Meta-analysis provided suggestive evidence for a differentially methylated locus within the chromosomal region affected by the PD-associated 22q11.2 deletion. Our findings elucidate novel disease pathways in PD and DLB and generate hypotheses for future molecular studies of Lewy body pathology.
Ground electronic state description of thiourea coordination in homoleptic Zn2+, Ni2+ and Co2+ complexes using sulfur K-edge X-ray absorption spectroscopy
Authors: Queen Matt S. , Jalilehvand Farideh , Szilagyi Robert K.
Published: October 2021

Sulfur K-edge X-ray absorption spectroscopy (XAS) was employed to experimentally characterize the coordinative bond between the thiourea (TU) or thiocarbamide ligand and transition metal (TM) ions Zn2+, Co2+ and Ni2+ in distorted tetrahedral and octahedral homoleptic coordination environments. Comparisons of XAS spectra of the free TU ligand and [Zn(TU)4]2+, [Co(TU)4]2+ and [Ni(TU)6]2+ complexes clearly identify spectral features unique to TM2+–S(TU) bonding. Quantitative analysis of pre-edge intensities describes the covalency of Ni2+—S(TU) and Co2+—S(TU) bonding to be at most 21% and 9% as expressed by the S 3p contributions per TM 3d electron hole. Using relevant Ni2+ complexes with dithiocarbamate and thioether ligands, we evaluated the empirical S 1s → 3p transition dipole integrals developed for S-donor ligands and their dependence on heteroatom substitutions. With the aid of density functional theory-based ground electronic state calculations, we found evidence for the need of using a transition dipole that is dependent on the presence of conjugated heteroatom (N) substitution in these S-donor ligands.