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VAR2CSA mediates sequestration of Plasmodium falciparum-infected erythrocytes in the placenta, increasing the risk of poor pregnancy outcomes. Naturally acquired antibodies (Ab) to placental parasites at delivery have been associated with improved pregnancy outcomes, but Ab levels and how early in pregnancy Ab must be present in order to eliminate placental parasites before delivery remains unknown. Antibodies to individual Duffy-binding like domains of VAR2CSA have been studied, but the domains lack many of the conformational epitopes present in full-length VAR2CSA (FV2). Thus, the purpose of this study was to describe the acquisition of Ab to FV2 in women residing in high and low transmission areas and determine how Ab levels during pregnancy correlate with clearance of placental parasites. Plasma samples collected monthly throughout pregnancy from pregnant women living in high and low transmission areas in Cameroon were evaluated for Ab to FV2 and the proportion of high avidity Ab (i.e., Ab that remain bound in the presence of 3M NH(4)SCN) was assessed. Ab levels and proportion of high avidity Ab were compared between women with placental malaria (PM(+)) and those without (PM(-)) at delivery. Results showed that PM(-) women had significantly higher Ab levels (p = 0.0047) and proportion of high avidity Ab (p = 0.0009) than PM(+) women throughout pregnancy. Specifically, women with moderate to high Ab levels (>5,000 MFI) and those with ≥ 35% high avidity Ab at 5-6 months were found to have 2.3 (95% CI, 1.0-4.9) and 7.6-fold (p = 0.0013, 95% CI: 1.2-50.0) reduced risk of placental malaria, respectively. These data show that high levels of Ab to FV2, particularly those with high avidity for FV2, produced by mid-pregnancy are important in clearing parasites from the placenta. Both high Ab levels and proportion of high avidity Ab to FV2 may serve as correlates of protection for assessing immunity against placental malaria.

Deubiquitinating enzymes (DUBs) have been increasingly implicated in regulation of cellular processes, but a functional role for Ubiquitin C-terminal Hydrolases (UCHs), which has been largely relegated to processing of small ubiquitinated peptides, remains unexplored. One member of the UCH family, UCH L1, is expressed in a number of malignancies suggesting that this DUB might be involved in oncogenic processes, and increased expression and activity of UCH L1 have been detected in EBV-immortalized cell lines. Here we present an analysis of genes regulated by UCH L1 shown by microarray profiles obtained from cells in which expression of the gene was inhibited by RNAi. Microarray data were verified with subsequent real-time PCR analysis. We found that inhibition of UCH L1 activates genes that control apoptosis, cell cycle arrest and at the same time suppresses expression of genes involved in proliferation and migration pathways. These findings are complemented by biological assays for apoptosis, cell cycle progression and migration that support the data obtained from microarray analysis, and suggest that the multi-functional molecule UCH L1 plays a role in regulating principal pathways involved in oncogenesis.

Deubiquitinating enzymes (DUBs) are involved in the regulation of distinct critical cellular processes. Ubiquitin C-terminal Hydrolase L1 (UCH L1) has been linked to several neurological diseases as well as human cancer, but the physiological targets and the regulation of UCH L1 expression in vivo have been largely unexplored. Here we demonstrate that UCH L1 up-regulates beta-catenin/TCF signaling: UCH L1 forms endogenous complexes with beta-catenin, stabilizes it and up-regulates beta-catenin/TCF-dependent transcription. We also show that, reciprocally, beta-catenin/TCF signaling up-regulates expression of endogenous UCH L1 mRNA and protein. Moreover, using ChIP assay and direct mutagenesis we identify two TCF4-binding sites on the uch l1 promoter that are involved in this regulation. Since the expression and deubiquitinating activity of UCH L1 are required for its own basic promoter activity, we propose that UCH L1 up-regulates its expression by activation of the oncogenic beta-catenin/TCF signaling in transformed cells.

Introduction: This paper describes how mortality among hospitalised COVID-19 patients changed during the first three waves of the epidemic in Italy., Methods: This prospective cohort study used the Kaplan-Meier method to analyse the time-dependent probability of death of all of the patients admitted to a COVID-19 referral centre in Milan, Italy, during the three consecutive periods of: 21 February-31 July 2020 (first wave, W1), 1 August 2020-31 January 2021 (second wave, W2), and 1 February-30 April 2021 (third wave, W3). Cox models were used to examine the association between death and the period of admission after adjusting for age, biological sex, the time from symptom onset to admission, disease severity upon admission, obesity, and the comorbidity burden., Results: Of the 2,023 COVID-19 patients admitted to our hospital during the study period, 553 (27.3%) were admitted during W1, 838 (41.5%) during W2, and 632 (31.2%) during W3. The crude mortality rate during W1, W2 and W3 was respectively 21.3%, 23.7% and 15.8%. After adjusting for potential confounders, hospitalisation during W2 or W3 was independently associated with a significantly lower risk of death than hospitalisation during W1 (adjusted hazard ratios [AHRs]: 0.75, 95% confidence interval [CI] 0.59-0.95, and 0.58, 95% CI 0.44-0.77). Among the patients aged >75 years, there was no significant difference in the probability of death during the three waves (AHRs during W2 and W3 vs W1: 0.93, 95% CI 0.65-1.33, and 0.88, 95% CI 0.59-1.32), whereas those presenting with critical disease during W2 and W3 were at significantly lower risk of dying than those admitted during W1 (AHRs 0.61, 95% CI 0.43-0.88, and 0.44, 95% CI 0.28-0.70)., Conclusions: Hospitalisation during W2 and W3 was associated with a reduced risk of COVID-19 death in comparison with W1, but there was no difference in survival probability in patients aged >75 years., Competing Interests: The authors have declared that no competing interests exist.

A novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) is the source of a current pandemic (COVID-19) with devastating consequences in public health and economic stability. Using a peptide array to map the antibody response of plasma from healing patients (12) and heathy patients (6), we identified three immunodominant linear epitopes, two of which correspond to key proteolytic sites on the spike protein (S1/S2 and S2') known to be critical for cellular entry. We show biochemical evidence that plasma positive for the epitope adjacent to the S1/S2 cleavage site inhibits furin-mediated proteolysis of spike., Competing Interests: The authors have declared that no competing interests exist.

Nature shows as human beings live and grow inside social structures. This assumption allows us to explain and explore how it may shape most of our behaviours and choices, and why we are not just blindly driven by instincts: our decisions are based on more complex cognitive reasons, based on our connectedness on different spaces. Thus, human cooperation emerges from this complex nature of social network. Our paper, focusing on the evolutionary dynamics, is intended to explore how and why it happens, and what kind of impact is caused by homophily among people. We investigate the evolution of human cooperation using evolutionary game theory on multiplex. Multiplexity, as an extra dimension of analysis, allows us to unveil the hidden dynamics and observe non-trivial patterns within a population across network layers. More importantly, we find a striking role of homophily, as the higher the homophily between individuals, the quicker is the convergence towards cooperation in the social dilemma. The simulation results, conducted both macroscopically and microscopically across the network layers in the multiplex, show quantitatively the role of homophily in human cooperation.

During an anthrax outbreak at the Pollino National Park (Basilicata, Italy) in 2004, diseased cattle were buried and from these anthrax-foci Bacillus anthracis endospores still diffuse to the surface resulting in local accumulations. Recent data suggest that B. anthracis multiplies in soil outside the animal-host body. This notion is supported by the frequent isolation of B. anthracis from soil lacking one or both virulence plasmids. Such strains represent an evolutionary dead end, as they are likely no longer able to successfully infect new hosts. This loss of virulence plasmids is explained most simply by postulating a soil-borne life cycle of the pathogen. To test this hypothesis we investigated possible microevolution at two natural anthrax foci from the 2004 outbreak. If valid, then genotypes of strains isolated from near the surface at these foci should be on a different evolutionary trajectory from those below residing in deeper-laying horizons close to the carcass. Thus, the genetic diversity of B. anthracis isolates was compared conducting Progressive Hierarchical Resolving Assays using Nucleic Acids (PHRANA) and next generation Whole Genome Sequencing (WGS). PHRANA was not discriminatory enough to resolve the fine genetic relationships between the isolates. Conversely, WGS of nine isolates from near-surface and nine from near-carcass revealed five isolate specific SNPs, four of which were found only in different near-surface isolates. In support of our hypothesis, one surface-isolate lacked plasmid pXO1 and also harbored one of the unique SNPs. Taken together, our results suggest a limited soil-borne life cycle of B. anthracis.

Background: Cardiovascular disease (CVD) is the leading cause of death worldwide and new approaches for both diagnosis and treatment are required. Autoantibodies directed against apolipoprotein A-I (ApoA-I) represent promising biomarkers for use in risk stratification of CVD and may also play a direct role in pathogenesis., Methodology: To characterize the anti-ApoA-I autoantibody response, we measured the immunoreactivity to engineered peptides corresponding to the different alpha-helical regions of ApoA-I, using plasma from acute chest pain cohort patients known to be positive for anti-ApoA-I autoantibodies., Principal Findings: Our results indicate that the anti-ApoA-I autoantibody response is strongly biased towards the C-terminal alpha-helix of the protein, with an optimized mimetic peptide corresponding to this part of the protein recapitulating the diagnostic accuracy for an acute ischemic coronary etiology (non-ST segment elevation myocardial infarction and unstable angina) obtainable using intact endogenous ApoA-I in immunoassay. Furthermore, the optimized mimetic peptide strongly inhibits the pathology-associated capacity of anti-ApoA-I antibodies to elicit proinflammatory cytokine release from cultured human macrophages., Conclusions: In addition to providing a rationale for the development of new approaches for the diagnosis and therapy of CVD, our observations may contribute to the elucidation of how anti-ApoA-I autoantibodies are elicited in individuals without autoimmune disease.

To understand the nature of age-related changes in enumeration abilities we measured two ERP responses -N2pc and CDA, associated respectively to attentive individuation and VWM- and posterior alpha band (8-15 Hz) event-related desynchronization (ERD), traditionally linked to enhanced target processing. Two groups of old and young participants enumerated a variable number (1-6) of targets presented among distractors. Older participants were less accurate in enumerating targets. ERP results in old participants showed a suppression of N2pc amplitudes for all numerosities, and a decrease in CDA only for the largest set (4-6 targets). In contrast with the pattern for young adults, time/frequency results on older adults revealed neither a modulation of alpha oscillations as a function of target numerosity, nor an effect of ERD lateralization. These patterns indicate that both attention and working memory contribute to the age-related decline in enumeration, and point to an overall decrease in the activity of the visual areas responsible for the processing of the hemifield where the relevant objects are presented.