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BackgroundTo develop an effective vaccine against Plasmodium vivax, the most widely dispersed human malaria parasite, it is critical to understand how coinfections with other pathogens could impact malaria-specific immune response. A recent conceptual study proposed that Epstein-Barr virus (EBV), a highly prevalent human herpesvirus that establishes lifelong persistent infection, may influence P. vivax antibody responses. Here, it was investigated whether EBV could impact the longevity of humoral immune response to P. vivax.Methodology/principal findingsA 14-year follow-up study was carried out among long-term P. vivax-exposed Amazonian individuals (272, median age 35 years), and included 9 cross-sectional surveys at periods of high and low malaria transmission. The experimental approach focused on monitoring antibodies to the major blood-stage P. vivax vaccine candidate, the Duffy binding protein region II (DBPII-Sal1), including a novel engineered DBPII-based vaccine targeting conserved epitopes (DEKnull-2). In parallel, the status of EBV infection was determined over time by the detection of circulating EBV DNA (EBV-DNAemia) and EBV-specific antibodies to lytic (VCAp18) or latent (EBNA1) antigens. Regardless of the malaria transmission period, the results demonstrated that one or multiple episodes of EBV-DNAemia did not influence the longevity of DBPII immune responses to both strain-specific (Sal-1) or strain-transcending (DEKnull-2) antibodies. Also, the average time in which DBPII-responders lost their antibodies was unrelated to the EBV serostatus. Considering all malaria cases detected during the study, there was a predominance of P. vivax mono-infection (76%), with a positive correlation between malaria infection and EBV-DNAemia.Conclusions/significanceIn an immunocompetent P. vivax-exposed adult population neither sporadic episodes of EBV-DNAemia nor antibody responses to lytic/latent EBV antigens influence the longevity of both strain-specific and strain-transcending DBPII immune responses. Further studies should investigate the role of acute P. vivax infection in the activation of EBV replication cycle.

BackgroundThe simultaneous infection of Plasmodium falciparum and Epstein-Barr virus (EBV) could promote the development of the aggressive endemic Burkitt's Lymphoma (eBL) in children living in P. falciparum holoendemic areas. While it is well-established that eBL is not related to other human malaria parasites, the impact of EBV infection on the generation of human malaria immunity remains largely unexplored. Considering that this highly prevalent herpesvirus establishes a lifelong persistent infection on B-cells with possible influence on malaria immunity, we hypothesized that EBV co-infection could have impact on the naturally acquired antibody responses to P. vivax, the most widespread human malaria parasite.Methodology/principal findingsThe study design involved three cross-sectional surveys at six-month intervals (baseline, 6 and 12 months) among long-term P. vivax exposed individuals living in the Amazon rainforest. The approach focused on a group of malaria-exposed individuals whose EBV-DNA (amplification of balf-5 gene) was persistently detected in the peripheral blood (PersVDNA, n = 27), and an age-matched malaria-exposed group whose EBV-DNA could never be detected during the follow-up (NegVDNA, n = 29). During the follow-up period, the serological detection of EBV antibodies to lytic/ latent viral antigens showed that IgG antibodies to viral capsid antigen (VCA-p18) were significantly different between groups (PersVDNA > NegVDNA). A panel of blood-stage P. vivax antigens covering a wide range of immunogenicity confirmed that in general PersVDNA group showed low levels of antibodies as compared with NegVDNA. Interestingly, more significant differences were observed to a novel DBPII immunogen, named DEKnull-2, which has been associated with long-term neutralizing antibody response. Differences between groups were less pronounced with blood-stage antigens (such as MSP1-19) whose levels can fluctuate according to malaria transmission.Conclusions/significanceIn a proof-of-concept study we provide evidence that a persistent detection of EBV-DNA in peripheral blood of adults in a P. vivax semi-immune population may impact the long-term immune response to major malaria vaccine candidates.

Plasmodium vivax blood-stage invasion into reticulocyte is critical for parasite development. Thus, validation of novel parasite invasion ligands is essential for malaria vaccine development. Recently, we demonstrated that EBP2, a Duffy binding protein (DBP) paralog, is antigenically distinct from DBP and could not be functionally inhibited by anti-DBP antibodies. Here, we took advantage of a small outbreak of P.vivax malaria, located in a non-malarious area of Brazil, to investigate for the first time IgM/IgG antibodies against EBP2 and DEKnull-2 (an engineering DBPII vaccine) among individuals who had their first and brief exposure to P.vivax (16 cases and 22 non-cases). Our experimental approach included 4 cross sectional surveys at 3-month interval (12-month follow-up). The results demonstrated that while a brief initial P.vivax infection was not efficient to induce IgM/ IgG antibodies to either EBP2 or DEKnull-2, IgG antibodies against DEKnull-2 (but not EBP2) were boosted by recurrent blood-stage infections following treatment. Of interest, in most recurrent P. vivax infections (4 out of 6 patients) DEKnull-2 IgG antibodies were sustained for 6 to 12 months. Polymorphisms in the ebp2 gene does not seem to explain EBP2 low immunogenicity as the ebp2 allele associated with the P.vivax outbreak presented high identity to the original EBP2 isolate used as recombinant protein. Although EBP2 antibodies were barely detectable after a primary episode of P.vivax infection, EBP2 was highly recognized by serum IgG from long-term malaria-exposed Amazonians (range from 35 to 92% according to previous malaria episodes). Taken together, the results showed that individuals with a single and brief exposure to P.vivax infection develop very low anti-EBP2 antibodies, which tend to increase after long-term malaria exposure. Finally, the findings highlighted the potential of DEKnull-2 as a vaccine candidate, as in non-immune individuals anti-DEKnull-2 IgG antibodies were boosted even after a brief exposure to P.vivax blood stages. Author summary Vaccines might be a crucial component of the current efforts to malaria control and elimination, and much of the vaccine-related research on P. vivax has been focused on region II of the Duffy binding protein (DBPII), a ligand for human blood-stage infection. Recently, the newly described Erythrocyte binding protein 2 (EBP2), a P.vivax DBP paralog that it is antigenically distinct from DBP, was identified as potential vaccine targets. To date, scarce data are available about the naturally acquired immunity to EBP2. In a small outbreak of P.vivax malaria, located in a non-malarious area, we investigated whether a first P.vivax exposure induces antibodies against EBP2 that could be boosted by P.vivax recurrent infections. In parallel, we included an engineered DBPII vaccine (named DEKnull-2) whose antibody response were previously associated with broadly neutralizing P.vivax antibodies. This study shows EBP2, compared with DEKnull-2, was poorly immunogenic among individuals who experienced their first blood-stage P. vivax malaria infection. However, EBP2 was highly immunogenic in long-term malaria exposed individuals, reinforcing its potential as a P. vivax blood-stage vaccine candidate. Finally, our results reinforce that multiple blood-stage antigens should be targeted for the development of efficient vaccines against P. vivax.

Malaria remains a major public health problem worldwide, and Plasmodium vivax is the most widely distributed malaria parasite. Naturally acquired binding inhibitory antibodies (BIAbs) to region II of the Duffy binding protein (DBPII), a P. vivax ligand that is critical for reticulocyte invasion, are associated with a reduced risk of clinical malaria. Owing to methodological issues in evaluating antibodies that inhibit the DBPII–DARC interaction, a limited number of studies have investigated DBPII BIAbs in P. vivax-exposed populations. Based on the assumption that individuals with a consistent BIAb response are characterized by strain-transcending immune responses, we hypothesized that detecting broadly reactive DBPII antibodies would indicate the presence of BIAb response. By taking advantage of an engineered DBPII immunogen targeting conserved DBPII neutralizing epitopes (DEKnull-2), we standardized a multiplex flow cytometry-based serological assay to detect broadly neutralizing IgG antibodies. For this study, a standard in vitro cytoadherence assay with COS-7 cells expressing DBPII was used to test for DBPII BIAb response in long-term P. vivax-exposed Amazonian individuals. Taken together, the results demonstrate that this DBPII-based multiplex assay facilitates identifying DBPII BIAb carriers. Of relevance, the ability of the multiplex assay to identify BIAb responders was highly accurate when the positivity for all antigens was considered. In conclusion, the standardized DBPII-based flow cytometric assay confirmed that DBPII-BIAb activity was associated with the breadth rather than the magnitude of anti-DBPII antibodies. Altogether, our results suggest that multiplex detection of broadly DBPII-reactive antibodies facilitates preliminary screening of BIAb responders.

Encoded Library Technology (ELT) has streamlined the identification of chemical ligands for protein targets in drug discovery. Here, the authors optimize the ELT approach to screen multiple proteins in parallel and identify promising targets and antibacterial compounds forS. aureus, A. baumannii and M. tuberculosis.

BackgroundA low proportion of P. vivax-exposed individuals acquire protective strain-transcending neutralizing IgG antibodies that are able to block the interaction between the Duffy binding protein II (DBPII) and its erythrocyte-specific invasion receptor. In a recent study, a novel surface-engineered DBPII-based vaccine termed DEKnull-2, whose antibody response target conserved DBPII epitopes, was able to induce broadly binding-inhibitory IgG antibodies (BIAbs) that inhibit P. vivax reticulocyte invasion. Toward the development of DEKnull-2 as an effective P. vivax blood-stage vaccine, we investigate the relationship between naturally acquired DBPII-specific IgM response and the profile of IgG antibodies/BIAbs activity over time.Methodology/principal findingsA nine-year follow-up study was carried-out among long-term P. vivax-exposed Amazonian individuals and included six cross-sectional surveys at periods of high and low malaria transmission. DBPII immune responses associated with either strain-specific (Sal1, natural DBPII variant circulating in the study area) or conserved epitopes (DEKnull-2) were monitored by conventional serology (ELISA-detected IgM and IgG antibodies), with IgG BIAbs activity evaluated by functional assays (in vitro inhibition of DBPII-erythrocyte binding). The results showed a tendency of IgM antibodies toward Sal1-specific response; the profile of Sal1 over DEKnull-2 was not associated with acute malaria and sustained throughout the observation period. The low malaria incidence in two consecutive years allowed us to demonstrate that variant-specific IgG (but not IgM) antibodies waned over time, which resulted in IgG skewed to the DEKnull-2 response. A persistent DBPII-specific IgM response was not associated with the presence (or absence) of broadly neutralizing IgG antibody response.Conclusions/significanceThe current study demonstrates that long-term exposure to low and unstable levels of P. vivax transmission led to a sustained DBPII-specific IgM response against variant-specific epitopes, while sustained IgG responses are skewed to conserved epitopes. Further studies should investigate on the role of a stable and persistent IgM antibody response in the immune response mediated by DBPII.

ABSTRACT Many pathogens evolve extensive genetic variation in virulence proteins as a strategy to evade host immunity. This poses a significant challenge for the host to develop broadly neutralizing antibodies. In Plasmodium falciparum, we show that a mechanism to circumvent this challenge is to elicit antibodies to cryptic epitopes that are not under immune pressure. We previously discovered that antibodies to the Plasmodium vivax invasion protein, PvDBP, cross-react with P. falciparum VAR2CSA, a distantly related virulence factor that mediates placental malaria. Here, we describe the molecular mechanism underlying this cross-species immunity. We identified an epitope in subdomain 1 (SD1) within the Duffy binding-like (DBL) domain of PvDBP that gives rise to cross-reactive antibodies to VAR2CSA and show that human antibodies affinity purified against a synthetic SD1 peptide block parasite adhesion to chondroitin sulfate A (CSA) in vitro. The epitope in SD1 is subdominant and highly conserved in PvDBP, and in turn, SD1 antibodies target cryptic epitopes in P. falciparum VAR2CSA. The epitopes in VAR2CSA recognized by vivax-derived SD1 antibodies (of human and mouse origin) are distinct from those recognized by VAR2CSA immune serum. We mapped two peptides in the DBL5ε domain of VAR2CSA that are recognized by SD1 antibodies. Both peptides map to regions outside the immunodominant sites, and antibodies to these peptides are not elicited following immunization with VAR2CSA or natural infection with P. falciparum in pregnancy, consistent with the cryptic nature of these target epitopes. IMPORTANCE In this work, we describe a molecular mechanism of heterologous immunity between two distant species of Plasmodium. Our results suggest a mechanism that subverts the classic parasite strategy of presenting highly polymorphic epitopes in surface antigens to evade immunity to that parasite. This alternative immune pathway can be exploited to protect pregnant women from falciparum placental malaria by designing vaccines to cryptic epitopes that elicit broadly inhibitory antibodies against variant parasite strains.

Ketamine is a popular recreational drug among young people in Hong Kong. Long-term abuse of ketamine can lead to acute urological and medical issues, which often require immediate care at emergency rooms. Many patients require short-term hospitalization for medical management. This opens a brief time window, within which mental health professionals could engage young people who abuses ketamine in psychosocial, functional, and lifestyle interventions. The Crisis Accommodation Program (CAP) is a short-term hospitalization and community support program that addresses the health care needs of young people who abuse ketamine. During short-term hospitalization, the patient participates in a range of cognitive and psychosocial assessments, motivational interviewing, emotions management, and lifestyle re-design interventions. Upon discharge, social work professionals of non-government agencies continue to work with the patients on their action plans in the community. This evaluation study uses a quasi-experimental non-equivalent group design, in which the outcomes of the treatment group (n = 84) are compared with a comparison group (n = 34) who have a history of ketamine abuse but who have not joined the treatment program. The results confirm that the treatment group showed significant increases in motivation for treatment, reduction in drug use, improvement in cognitive screening tests, healthy lifestyle scores, and self-efficacy in avoidance of drugs over 13 weeks. When compared with the comparison group, the treatment group had significant decreases in anxiety and treatment needs and had moved from pre-contemplation to the contemplation or preparation stage. However, there were no significant changes in outcome measures covering lifestyle or self-efficacy in drug avoidance. Overall, the CAP is effective in reducing drug use, anxiety, and helping patients to move from pre-contemplation to the contemplation or preparation stage of change. The study results suggest that health care professionals can successfully engage young people who abuse ketamine to participate in a package of psychosocial interventions, motivational interviewing, and lifestyle re-design during their hospital stay for management of urological problems. The CAP also highlights the importance of collaboration between hospitals and community social services in the management of addiction.

Plasmodium vivax remains a global health problem and its ability to cause relapses and subpatent infections challenge control and elimination strategies. Even in low malaria transmission settings, such as the Amazon basin, where progress in malaria control has caused a remarkable reduction in case incidence, a recent increase in P. vivax transmission demonstrates the continued vulnerability of P.vivax-exposed populations. As part of a search for complementary approaches to P.vivax surveillance in areas in which adults are the majority of the exposed-population, here we evaluated the potential of serological markers covering a wide range of immunogenicity to estimate malaria transmission trends. For this, antibodies against leading P. vivax blood-stage vaccine candidates were assessed during a 9 year follow-up study among adults exposed to unstable malaria transmission in the Amazon rainforest. Circulating antibody levels against immunogenic P. vivax proteins, such as the Apical Membrane Antigen-1, were a sensitive measure of recent P. vivax exposure, while antibodies against less immunogenic proteins were indicative of naturally-acquired immunity, including the novel engineered Duffy binding protein II immunogen (DEKnull-2). Our results suggest that the robustness of serology to estimate trends in P.vivax malaria transmission will depend on the immunological background of the study population, and that for adult populations exposed to unstable P.vivax malaria transmission, the local heterogeneity of antibody responses should be considered when considering use of serological surveillance.

BACKGROUND:The human malaria parasite Plasmodium vivax infects red blood cells through a key pathway that requires interaction between Duffy binding protein II (DBPII) and its receptor on reticulocytes, the Duffy antigen/receptor for chemokines (DARC). A high proportion of P. vivax-exposed individuals fail to develop antibodies that inhibit DBPII-DARC interaction, and genetic factors that modulate this humoral immune response are poorly characterized. Here, we investigate if DBPII responsiveness could be HLA class II-linked. METHODOLOGY/PRINCIPAL FINDINGS:A community-based open cohort study was carried out in an agricultural settlement of the Brazilian Amazon, in which 336 unrelated volunteers were genotyped for HLA class II (DRB1, DQA1 and DQB1 loci), and their DBPII immune responses were monitored over time (baseline, 6 and 12 months) by conventional serology (DBPII IgG ELISA-detected) and functional assays (inhibition of DBPII-erythrocyte binding). The results demonstrated an increased susceptibility of the DRB1*13:01 carriers to develop and sustain an anti-DBPII IgG response, while individuals with the haplotype DRB1*14:02-DQA1*05:03-DQB1*03:01 were persistent non-responders. HLA class II gene polymorphisms also influenced the functional properties of DBPII antibodies (BIAbs, binding inhibitory antibodies), with three alleles (DRB1*07:01, DQA1*02:01 and DQB1*02:02) comprising a single haplotype linked with the presence and persistence of the BIAbs response. Modelling the structural effects of the HLA-DRB1 variants revealed a number of differences in the peptide-binding groove, which is likely to lead to altered antigen binding and presentation profiles, and hence may explain the differences in subject responses. CONCLUSIONS/SIGNIFICANCE:The current study confirms the heritability of the DBPII antibody response, with genetic variation in HLA class II genes influencing both the development and persistence of IgG antibody responses. Cellular studies to increase knowledge of the binding affinities of DBPII peptides for class II molecules linked with good or poor antibody responses might lead to the development of strategies for controlling the type of helper T cells activated in response to DBPII.

ResumoA altura dominante (Ho) de 120 parcelas georreferenciadas (600m² cada) foi estimada através de diversas medidas de distribuição, máximas locais e densidade derivada da varredura a laser com pequena impressão obtida em um povoamento florestal decíduo irregular. As parcelas foram distribuídas de forma a contemplar toda a variabilidade de alturas dominantes e o tipo de regeneração existente nos 112km² da área estudada, localizada na floresta de Haye, França. O modelo construído com variáveis de máxima local (Hmv5) e densidade de retornos (d9) foi capaz de estimar a Ho com alta acurácia, além de ser independente do tipo de povoamento, o que possibilitou sua aplicação em toda a floresta. A validação cruzada do modelo final mostrou que este explicou 98% da variabilidade observada nas parcelas em campo, com um RMSE de 0.77m (3.31%). Nenhum efeito drástico da escolha do MNT, densidade de retornos ou do posicionamento das parcelas foi detectado no modelo, sugerindo grande estabilidade. AbstractThe mean dominant heights of 120 georeferenced field sample plots (600m² each) were estimated from a range of canopy densities, distributions and local maxima metrics derived by a small-footprint laser scanner over various deciduous forest stands using regression analysis. The sample plots were distributed in order to better represent the variability in stand dominant height and regeneration practices throughout a 112km² study areas in Haye forest, France. The model constructed with local maxima (Hmv5) and a LIDAR density metric (d9) was able to estimate Ho with a very high accuracy and was not sensitive to stand types. Cross-validation showed that the final model explained 98% of the variability in ground-truth dominant height, with a RMSE of 0.77m (3.31%). No drastic effects of DTM, echo densities, or positioning errors were found in the models.

Nature Communications 8: Article number: 16081 (2017); Published: 17 July 2017, Updated: 13 July 2018 The original version of this Article omitted the following from the Acknowledgements: ‘We thank Robert Kirkpatrick for implementing the high throughput protein design strategy that enabled screeningand triage of essential A.

No presente trabalho, um teste imunoenzimático por competição (cELISA) foi padronizado com a proteína recombinante de superfície rMSP5, clonada a partir do gene msp5 do isolado PR1 de A. marginale. O sequenciamento mostrou que o gene que codifica a rMSP5/PR1 tem 98% de identidade com os isolados Flórida e Santa Maria, 97% com isolados de Pernambuco, Brasil e Havana, Cuba e 91% com A. centrale. O teste de cELISA-PR1 foi comparado com os testes de IFI e cELISA-USA. Para a padronização e validação do cELISA-PR1, foram utilizados 380 soros bovinos comprovadamente positivos ou negativos pelo cELISA-USA. Desse total, 245 soros positivos eram de animais de área endêmica e 135 soros eram negativos, de área livre de anaplasmose. Na padronização, foram utilizados 283 soros de bovinos, dos quais 135 eram negativos e 148 positivos. Os testes de cELISA-PR1 e IFI apresentaram especificidade de 100 e 99,3%, sensibilidade de 100 e 98%, com coeficiente kappa de 0,993 e 0,978, respectivamente. Na validação do teste, foram utilizados 245 soros de bovinos de áreas endêmicas para anaplasmose, testados pelo cELISA-PR1 e IFI e apresentaram especificidade de 96,7 e 69,1%, sensibilidade de 98,9 e 96,3% e coeficiente kappa de 0,956 e 0,699, respectivamente. Esses resultados permitem afirmar que o teste de cELISA-PR1 apresentou performance equivalente ao cELISA-USA, podendo também ser utilizado em estudos epidemiológicos, programas de controle e movimentação internacional de animais, enquanto a IFI, com os resultados menos precisos apresentados, não deve ser utilizada em situações que requerem maior rigor no diagnóstico.A competitive enzyme-linked immunosorbent test using the PR1 recombinant major surface protein 5 (rMSP5-PR1-ELISA) of Anaplasma marginale was standardized and validated using sera from anaplasmosis free and endemic regions. The sequencing of the msp5 gene of PR1 isolate showed 98% of identity with the Florida and Saint Maries isolates, 97% with Brazil (Pernambuco) and Havana isolates; and 91% with A. centrale. The cELISA-PR1 test was compared to IFI and cELISA-USA. For the standardization and validation of the cELISA-PR1, 380 bovine sera were used, whereas 245 truly positives and 135 truly negatives sera tested by the cELISA-USA. In the standardization of the cELISA-PR1 135 negative and 148 positive bovine sera were used. The cELISA-PR1 and IFI tests showed 100 and 99.3% specificity, 100 and 98%, sensibility, and a kappa coefficient of 0.993 and 0.978, respectively. For test validation, 245 bovine sera from an anaplasmosis endemic area were analyzed by the cELISA-PR1 and IFI, which showed 96.7 and 69.1% specificity, 98.9 e 96.3% sensibility and kappa coefficient of 0.956 and 0.699, respectively. These results indicate that the cELISA-PR1, likewise the cELISA-USA, could sensitively and specifically detect cattle naturally infected with A. marginale and would be recommended for epidemiological studies, eradications program, and regulation of international cattle movement, while IFI, which presented lower specificity should not be used in situations that demand more specific diagnosis.

The development of an effective immune response can help decrease mortality from malaria and its clinical symptoms. However, this mechanism is complex and has significant inter-individual variation, most likely owing to the genetic contribution of the human host. Therefore, this study aimed to investigate the influence of polymorphisms in genes involved in the costimulation of B-lymphocytes in the naturally acquired humoral immune response against proteins of the asexual stage of Plasmodium vivax. A total of 319 individuals living in an area of malaria transmission in the Brazilian Amazon were genotyped for four SNPs in the genes CD40, CD40L, BLYS and CD86. In addition, IgG antibodies against P. vivax apical membrane antigen 1 (PvAMA-1), Duffy binding protein (PvDBP) and merozoite surface protein 1 (PvMSP-119) were detected by ELISA. The SNP BLYS -871C>T was associated with the frequency of IgG responders to PvAMA-1 and PvMSP-119. The SNP CD40 -1C>T was associated with the IgG response against PvDBP, whereas IgG antibody titers against PvMSP-119 were influenced by the polymorphism CD86 +1057G>A. These data may help to elucidate the immunological aspects of vivax malaria and consequently assist in the design of malaria vaccines.

To avoid mutations in the genome, DNA replication is generally followed by DNA mismatch repair (MMR). MMR starts when a MutS homolog recognizes a mismatch and undergoes an ATP-dependent transformation to an elusive sliding clamp state. How this transient state promotes MutL homolog recruitment and activation of repair is unclear. Here we present a crystal structure of the MutS/MutL complex using a site-specifically crosslinked complex and examine how large conformational changes lead to activation of MutL. The structure captures MutS in the sliding clamp conformation, where tilting of the MutS subunits across each other pushes DNA into a new channel, and reorientation of the connector domain creates an interface for MutL with both MutS subunits. Our work explains how the sliding clamp promotes loading of MutL onto DNA, to activate downstream effectors. We thus elucidate a crucial mechanism that ensures that MMR is initiated only after detection of a DNA mismatch.

In severe COVID-19-related respiratory failure, extracorporeal membrane oxygenation (ECMO) is a useful modality that is used to provide effective oxygenation and ventilation to the patient. This descriptive study aimed to investigate and compare the outcomes between COVID-19-infected patients and patients who were not infected and required ECMO support. A retrospective study was undertaken on a cohort of 82 adult patients ([Formula: see text]18-year-old) who required venoarterial (VA-ECMO) and venovenous (VV-ECMO) ECMO between January 2019 and December 2022 in a single academic center. Patients who were cannulated for COVID-19-related respiratory failure (C-group) were compared to patients who were cannulated for non-COVID etiologies (non-group). Patients were excluded if data were missing regarding cannulation, decannulation, presenting diagnosis, and survival status. Categorical data were reported as counts and percentages, and continuous data were reported as means with 95% confidence intervals. Out of the 82 included ECMO patients, 33 (40.2%) were cannulated for COVID-related reasons, and 49 (59.8%) were cannulated for reasons other than COVID-19 infection. Compared to the non-group, the C-group had a higher in-hospital (75.8% vs. 55.1%) and overall mortality rate (78.8% vs. 61.2%). The C-group also had an average hospital length of stay (LOS) of 46.6 ± 13.2 days and an average intensive care unit (ICU) LOS of 44.1 ± 13.3 days. The non-group had an average hospital LOS of 24.8 ± 6.6 days and an average ICU LOS of 20.8 ± 5.9 days. Subgroup analysis of patients only treated with VV-ECMO yielded a greater in-hospital mortality rate for the C-group compared to the non-group (75.0% vs. 42.1%). COVID-19-infected patients may experience different morbidity and mortality rates as well as clinical presentations compared to non-COVID-infected patients when requiring ECMO support.

Sera of 708 animals (cows, heifers and calves) from 13 dairy herds in the Londrina region of Paraná, Brazil, were tested for antibodies to Anaplasma marginale by a competitive ELISA assay (cELISA). Ten 2 to 20 days old Holstein calves, from one of the 13 herds studied, were monitored during one year. Blood samples from each calf were collected monthly and tick burden counting was performed every fortnight. Percentage of infected erythrocytes was established by Giemsa-stained smears, and sera samples were examined by cELISA to detect antibodies against A. marginale. In the 13 herds, 92.94% of the animals were seropositive to A. marginale, which indicates that Londrina is an area of enzootic stability. Among the three animal categories (cows, heifers and calves), the rates were 98.29%, 96.64% and 81.25%, respectively. Passive transfer of maternal antibodies to calves was demonstrated by cELISA. From ten calves, nine (90%) were seropositive at the first sampling, revealing colostral antibodies anti-A . marginale. These antibodies remained in calves for 2 to 3 months. After this period the calves were infected with ticks, and then all of them were seropositive to Anaplasma. Five 4 to 7 months old calves showed rickettsemia ranging from 0.1% to 3.8%. Two of them were treated with tetracycline. The rickettsemia and clinical signs of anaplasmosis of these calves were coincident with tick burden increase.Soros de 708 animais (vacas, novilhas e bezerros) oriundos de 13 propriedades leiteiras da região de Londrina, Estado do Paraná, Brasil, foram testados para a presença de anticorpos contra Anaplasma marginale pelo teste ELISA competitivo (cELISA). Dez bezerros recém nascidos, pertencentes a um dos 13 rebanhos utilizados no levantamento sorológico, foram monitorados durante um ano. De cada bezerro foram colhidas amostras de sangue mensalmente e a cada quinze dias foi realizada a contagem de carrapatos. A porcentagem de eritrócitos parasitados foi determinada pela coloração de Giemsa em esfregaços sanguíneos e as amostras de soros foram submetidas ao cELISA para a detecção de anticorpos contra A. marginale. Dos animais dos rebanhos, 92,94% foram soropositivos para A. marginale indicando que a região de Londrina é uma área de estabilidade enzoótica. Nas três categorias de animais estudadas (vacas, novilhas e bezerros) as taxas de soropositivos foram de 98,29%, 96,64% e 81,25%, respectivamente. Nove dos 10 bezerros (90%) foram positivos pelo cELISA logo após o nascimento, o que demonstra a transferência de anticorpos colostrais. Os níveis de anticorpos colostrais foram detectados até o segundo e o terceiro mês de idade com um decréscimo neste período. Os níveis de anticorpos contra A. marginale voltaram a crescer nos meses seguintes, após os animais se infestarem com o Boophilus microplus, quando todos eram positivos. Cinco bezerros com idades entre quatro e sete meses apresentaram rickettsemias detectáveis pela coloração de Giemsa, variando de 0,1% a 3,8%, sendo que dois destes animais foram tratados com tetraciclina. Estas rickettsemias e os sinais clínicos apresentados por estes bezerros foram coincidentes com o aumento do número de carrapatos sobre os animais.

The Plasmodium vivax Duffy binding protein (PvDBP) and its erythrocytic receptor, the Duffy antigen receptor for chemokines (DARC), are involved in the major P. vivax erythrocyte invasion pathway. An open cohort study to analyze DARC genotypes and their relationship to PvDBP immune responses was carried out in 620 volunteers in an agricultural settlement of the Brazilian Amazon. Three cross-sectional surveys were conducted at 6-month intervals, comprising 395, 410, and 407 subjects, respectively. The incidence rates of P. vivax infection was 2.32 malaria episodes per 100 person-months under survey (95% confidence interval [CI] of 1.92-2.80/100 person-month) and, of P. falciparum, 0.04 per 100 person-months (95% CI of 0.007-0.14/100 person-month). The distribution of DARC genotypes was consistent with the heterogeneous ethnic origins of the Amazon population, with a predominance of non-silent DARC alleles: FY*A > FY*B. The 12-month follow-up study demonstrated no association between DARC genotypes and total IgG antibodies as measured by ELISA targeting PvDBP (region II, DBPII or regions II-IV, DBPII-IV). The naturally acquired DBPII specific binding inhibitory antibodies (BIAbs) tended to be more frequent in heterozygous individuals carrying a DARC-silent allele (FY*BES). These results provide evidence that DARC polymorphisms may influence the naturally acquired inhibitory anti-Duffy binding protein II immunity.

The basic varieties of the Classic Maya ceremonial bar are described; its formal histories outlined; and its iconographic potentials are delimited. The significant gestures used to hold the bar are traced, along with the bar, to the Middle Preclassic Olmec culture. With this genealogy, with regional differences in Classic representations, and in certain iconographic reflections, the Classic cermonial bar is shown to represent a kind of allegory through which various "origin stories" were anciently told and interpreted to explain, thus to rationalize, royal power and action

A área de estudo compreende aproximadamente 70 km2, localizada na porção Norte da cidade de Natal, com uma população de aproximadamente 300.000 habitantes. Mais de 30% da população da área é abastecida com água subterrânea. Estas, entretanto estão sendo degradadas pelas atividades do desenvolvimento urbano, em especial a disposição local de efluentes domésticos, com a contaminação das águas por nitrato. O presente trabalho objetiva elaborar um diagnóstico das condições hidroambientais com ênfase aos fatores condicionantes da qualidade das águas subterrâneas. A pluviosidade média é de 1687 mm anuais, com déficit hídrico de 533 mm entre os meses de setembro e fevereiro. Geologia composta por cobertura residual do Grupo Barreiras com sedimentos eólicos. Dos 577 pontos d’água existentes na área, 301 são poços escavados, 06 fonte natural e 270 são poços tubulares. O fluxo subterrâneo é divergente a partir da parte central da área e segue em direção aos rios Potengi e Doce. A análise de nitrato em 413 amostras de água de poços, revelou que 42,5% das mesmas estão com valores superiores ao limite permitido de 10 mg/L-N. A transmissividade do aquífero varia de 6,1×10-4 m2/s à 1,8×10-3 m2/s, e a condutividade hidráulica, de 2,2×10-6 à 6,3×10-5 m/s.

Author(s): Anoop Kumar [1,2]; Manisha Thakur [1]; Mohini Chaurasia [3]; S. J. S. Flora (corresponding author) [1,3] Dear Editor, The recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection resulted [...]

Background: To develop an effective vaccine against Plasmodium vivax, the most widely dispersed human malaria parasite, it is critical to understand how coinfections with other pathogens could impact malaria-specific immune response. A recent conceptual study proposed that Epstein-Barr virus (EBV), a highly prevalent human herpesvirus that establishes lifelong persistent infection, may influence P. vivax antibody responses. Here, it was investigated whether EBV could impact the longevity of humoral immune response to P. vivax. Methodology/principal findings: A 14-year follow-up study was carried out among long-term P. vivax-exposed Amazonian individuals (272, median age 35 years), and included 9 cross-sectional surveys at periods of high and low malaria transmission. The experimental approach focused on monitoring antibodies to the major blood-stage P. vivax vaccine candidate, the Duffy binding protein region II (DBPII-Sal1), including a novel engineered DBPII-based vaccine targeting conserved epitopes (DEKnull-2). In parallel, the status of EBV infection was determined over time by the detection of circulating EBV DNA (EBV-DNAemia) and EBV-specific antibodies to lytic (VCAp18) or latent (EBNA1) antigens. Regardless of the malaria transmission period, the results demonstrated that one or multiple episodes of EBV-DNAemia did not influence the longevity of DBPII immune responses to both strain-specific (Sal-1) or strain-transcending (DEKnull-2) antibodies. Also, the average time in which DBPII-responders lost their antibodies was unrelated to the EBV serostatus. Considering all malaria cases detected during the study, there was a predominance of P. vivax mono-infection (76%), with a positive correlation between malaria infection and EBV-DNAemia. Conclusions/significance: In an immunocompetent P. vivax-exposed adult population neither sporadic episodes of EBV-DNAemia nor antibody responses to lytic/latent EBV antigens influence the longevity of both strain-specific and strain-transcending DBPII immune responses. Further studies should investigate the role of acute P. vivax infection in the activation of EBV replication cycle. [ABSTRACT FROM AUTHOR]

Background: Disparities secondary to underinsurance present throughout the surgical care continuum. Community free clinics are uniquely capable to provide health care services to the medically underserved, but surgery often falls outside their scope of care. Methods: Retrospective chart review was conducted on consecutive community free clinic patients receiving free surgical services via referral to a partnering ambulatory surgery center between March 2016 and September 2021. Those with documented contact information were recruited 1-3 years post-procedure for long-term quality-of-life (LTQOL) outcomes assessment via modified Veterans RAND 12-item health survey. Results: Of 142 included patients, 95.7% identified as Hispanic/Latino and 75.6% were uninsured. Twelve patients had cancerous or precancerous lesions detected and/or removed through diagnostic or definitive procedures. 3.5% experienced postoperative complication including bacterial (n = 2) or fungal (n = 1) surgical site infection and wound dehiscence (n = 2). With a 48.9% response rate, no significant differences in sociodemographic or clinical characteristics were found between surveyed vs non-surveyed patients. Of surveyed patients, 59.7% and 52.2% reported pre-/post-operative improvement in physical health and emotional health, respectively. Discussion: Free diagnostic screening procedures provided timely diagnoses while free definitive surgeries safely and positively impacted long-term patient-reported physical health. Longitudinal, multidisciplinary follow-up and social support may be warranted to concurrently improve emotional and mental health in similarly underinsured populations. [ABSTRACT FROM AUTHOR]

The authors provide an overview of past and present trends in career guidance, career education, and vocational training in Hong Kong. Particular attention is given to evaluating career education policies and how these have evolved and affected practices in secondary schools over the past few decades. Topics also covered within the paper include students who drop out, mentor systems, teacher training, vocational training vs. university education, and parent involvement. Two representative case studies are used to illustrate successful programmes. The future development of career education and vocational training in Hong Kong is anticipated, and implications for school-based career counselling practices are considered.

The American Academy of Pediatrics, American College of Emergency Physicians, and Emergency Nurses Association have collaborated to identify practices and principles to guide the care of children, families, and staff in the challenging and uncommon event of the death of a child in the emergency department in this policy statement and in an accompanying technical report.