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Malaria sterile immunity has been reproducibly induced by immunization with Plasmodium radiation-attenuated sporozoites (RAS). Analyses of sera from RAS-immunized individuals allowed the identification of P. falciparum antigens, such as the circumsporozoite protein (CSP), the basis for the RTS, S and R21Matrix-M vaccines. Similar advances in P. vivax (Pv) vaccination have been elusive. We previously reported 42% (5/12) of sterile protection in malaria-unexposed, Duffy-positive (Fy +) volunteers immunized with PvRAS followed by a controlled human malaria infection (CHMI). Using a custom protein microarray displaying 515 Pv antigens, we found a significantly higher reactivity to PvCSP and one hypothetical protein (PVX_089630) in volunteers protected against P. vivax infection. In mock-vaccinated Fy + volunteers, a strong antibody response to CHMI was also observed. Although the Fy- volunteers immunized with non-irradiated Pv-infected mosquitoes (live sporozoites) did not develop malaria after CHMI, they recognized a high number of antigens, indicating the temporary presence of asexual parasites in peripheral blood. Together, our findings contribute to the understanding of the antibody response to P. vivax infection and allow the identification of novel parasite antigens as vaccine candidates.Trial registration: ClinicalTrials.gov number: NCT01082341.

Abstract Species composition of the healthy adult gut microbiota tends to be stable over time. Destabilization of the gut microbiome under the influence of different factors is the main driver of the microbial dysbiosis and subsequent impacts on host physiology. Here, we used metagenomics data from a Swedish longitudinal cohort, to determine the stability of the gut microbiome and uncovered two distinct microbial species groups; persistent colonizing species (PCS) and transient colonizing species (TCS). We validated the continuation of this grouping, generating gut metagenomics data for additional time points from the same Swedish cohort. We evaluated the existence of PCS/TCS across different geographical regions and observed they are globally conserved features. To characterize PCS/TCS phenotypes, we performed bioreactor fermentation with faecal samples and metabolic modeling. Finally, using chronic disease gut metagenome and other multi-omics data, we identified roles of TCS in microbial dysbiosis and link with abnormal changes to host physiology.

Abstract The characteristics of the host are crucial in the final outcome of COVID-19. Herein, the influence of genetic and clinical variants in COVID-19 severity was investigated in a total of 1350 patients. Twenty-one single nucleotide polymorphisms of genes involved in SARS-CoV-2 sensing as Toll-like-Receptor 7, antiviral immunity as the type I interferon signalling pathway (TYK2, STAT1, STAT4, OAS1, SOCS) and the vasoactive intestinal peptide and its receptors (VIP/VIPR1,2) were studied. To analyse the association between polymorphisms and severity, a model adjusted by age, sex and different comorbidities was generated by ordinal logistic regression. The genotypes rs8108236-AA (OR 0.12 [95% CI 0.02–0.53]; p = 0.007) and rs280519-AG (OR 0.74 [95% CI 0.56–0.99]; p = 0.03) in TYK2, and rs688136-CC (OR 0.7 [95% CI 0.5–0.99]; p = 0.046) in VIP, were associated with lower severity; in contrast, rs3853839-GG in TLR7 (OR 1.44 [95% CI 1.07–1.94]; p = 0.016), rs280500-AG (OR 1.33 [95% CI 0.97–1.82]; p = 0.078) in TYK2 and rs1131454-AA in OAS1 (OR 1.29 [95% CI 0.95–1.75]; p = 0.110) were associated with higher severity. Therefore, these variants could influence the risk of severe COVID-19.

Abstract Background Persons living with HIV (PWH) harbor an altered gut microbiome (higher abundance of Prevotella and lower abundance of Bacillota and Ruminococcus lineages) compared to non-infected individuals. Some of these alterations are linked to sexual preference and others to the HIV infection. The relationship between these lineages and metabolic alterations, often present in aging PWH, has been poorly investigated. Methods In this study, we compared fecal metagenomes of 25 antiretroviral-treatment (ART)-controlled PWH to three independent control groups of 25 non-infected matched individuals by means of univariate analyses and machine learning methods. Moreover, we used two external datasets to validate predictive models of PWH classification. Next, we searched for associations between clinical and biological metabolic parameters with taxonomic and functional microbiome profiles. Finally, we compare the gut microbiome in 7 PWH after a 17-week ART switch to raltegravir/maraviroc. Results Three major enterotypes (Prevotella, Bacteroides and Ruminococcaceae) were present in all groups. The first Prevotella enterotype was enriched in PWH, with several of characteristic lineages associated with poor metabolic profiles (low HDL and adiponectin, high insulin resistance (HOMA-IR)). Conversely butyrate-producing lineages were markedly depleted in PWH independently of sexual preference and were associated with a better metabolic profile (higher HDL and adiponectin and lower HOMA-IR). Accordingly with the worst metabolic status of PWH, butyrate production and amino-acid degradation modules were associated with high HDL and adiponectin and low HOMA-IR. Random Forest models trained to classify PWH vs. control on taxonomic abundances displayed high generalization performance on two external holdout datasets (ROC AUC of 80–82%). Finally, no significant alterations in microbiome composition were observed after switching to raltegravir/maraviroc. Conclusion High resolution metagenomic analyses revealed major differences in the gut microbiome of ART-controlled PWH when compared with three independent matched cohorts of controls. The observed marked insulin resistance could result both from enrichment in Prevotella lineages, and from the depletion in species producing butyrate and involved into amino-acid degradation, which depletion is linked with the HIV infection.

Bacteria of the genus Brucella are facultative intracellular parasites that cause brucellosis, a severe animal and human disease. Recently, a group of taxonomists merged the brucellae with the primarily free-living, phylogenetically related Ochrobactrum spp. in the genus Brucella. This change, founded only on global genomic analysis and the fortuitous isolation of some opportunistic Ochrobactrum spp. from medically compromised patients, has been automatically included in culture collections and databases. We argue that clinical and environmental microbiologists should not accept this nomenclature, and we advise against its use because (i) it was presented without in-depth phylogenetic analyses and did not consider alternative taxonomic solutions; (ii) it was launched without the input of experts in brucellosis or Ochrobactrum; (iii) it applies a non-consensus genus concept that disregards taxonomically relevant differences in structure, physiology, population structure, core-pangenome assemblies, genome structure, genomic traits, clinical features, treatment, prevention, diagnosis, genus description rules, and, above all, pathogenicity; and (iv) placing these two bacterial groups in the same genus creates risks for veterinarians, medical doctors, clinical laboratories, health authorities, and legislators who deal with brucellosis, a disease that is particularly relevant in low- and middle-income countries. Based on all this information, we urge microbiologists, bacterial collections, genomic databases, journals, and public health boards to keep the Brucella and Ochrobactrum genera separate to avoid further bewilderment and harm.

This paper describes a study exploring in-service (IS) and pre-service (PS) teachers' language ideologies about non-Spanish-speaking students' multilingualism in Chilean classrooms. A survey was answered by 69 IS teachers and 34 PS teachers in the Chilean school system. Both groups were asked about two dimensions: (a) teachers' knowledge and training in L2 pedagogies and their ideologies about students' L1 and multilingualism; and (b) immigrant students' access and integration into Chilean schools. We focus on dimension (a); the results indicate that the teachers from the IS and PS groups do not consider that students' L1 is an impediment to the acquisition of the target language. They declare that the preservation of the L1 boosts non-Spanish-speaking students' self-esteem and can help them to acquire new linguistic knowledge. However, the results show a lack of consistent strategies to approach multilingual classes. These results are discussed in the light of the need to train teachers of all disciplines in multilingualism and the demand for public policies to teach Spanish as an additional language in Chilean schools.

Abstract Background Population stratification based on interindividual variability in gut microbiota composition has revealed the existence of several ecotypes named enterotypes in humans and various animal species. Enterotypes are often associated with environmental factors including diet, but knowledge of the role of host genetics remains scarce. Moreover, enterotypes harbor functionalities likely associated with varying abilities and susceptibilities of their host. Previously, we showed that under controlled conditions, 60-day-old pig populations consistently split into two enterotypes with either Prevotella and Mitsuokella (PM enterotype) or Ruminococcus and Treponema (RT enterotype) as keystone taxa. Here, our aim was to rely on pig as a model to study the influence of host genetics to assemble enterotypes, and to provide clues on enterotype functional differences and their links with growth traits. Results We established two pig lines contrasted for abundances of the genera pairs specifying each enterotype at 60 days of age and assessed them for fecal microbiota composition and growth throughout three consecutive generations. Response to selection across three generations revealed, per line, an increase in the prevalence of the selected enterotype and in the average relative abundances of directly and indirectly selected bacterial genera. The PM enterotype was found less diverse than the RT enterotype but more efficient for piglet growth during the post-weaning period. Shotgun metagenomics revealed differentially abundant bacterial species between the two enterotypes. By using the KEGG Orthology database, we show that functions related to starch degradation and polysaccharide metabolism are enriched in the PM enterotype, whereas functions related to general nucleoside transport and peptide/nickel transport are enriched in the RT enterotype. Our results also suggest that the PM and RT enterotypes might differ in the metabolism of valine, leucin, and isoleucine, favoring their biosynthesis and degradation, respectively. Conclusion We experimentally demonstrated that enterotypes are functional ecosystems that can be selected as a whole by exerting pressure on the host genetics. We also highlight that holobionts should be considered as units of selection in breeding programs. These results pave the way for a holistic use of host genetics, microbiota diversity, and enterotype functionalities to understand holobiont shaping and adaptation. Video Abstract

Chitosan is a biocompatible, biodegradable, and antimicrobial polymer. Researchers have recently explored using chitosan nanoparticles to fight phytopathogenic fungi. This review aims to provide a comprehensive overview of studies conducted between 2013 and 2023 using the most popular databases for academic research on this topic. A systematic review was conducted using Software Rayyan to support the process. The search was conducted using the Web of Science, Scopus, and ScienceDirect databases. Out of the 752 records found from 2013–2023, only 83 articles were considered eligible for inclusion in the review after screening with inclusion and exclusion criteria. Most studies showed that chitosan nanoparticles are produced using sodium tripolyphosphate (TPP) through ionotropic gelation. However, using TPP has potential drawbacks and may have a synergistic effect with chitosan, which requires further investigation. TPP can affect the biological activity of the nanoparticle matrix. Furthermore, less than 10 out of the 83 articles reviewed in the time frame explored chitosan-only nanoparticles (nanochitosan) against phytopathogenic fungi. This shows the need for more research to determine the potential benefits of chitosan-only nanoparticles in control phytopathogenic fungi.

Archivo histórico de Kipus: Revista Andina de Letras y Estudios Culturales, 2004.

IntroductionThis article presents a model of political competition in which political parties, through clientelism strategies, vie for control of legislative seats. Parties exercise political violence to prevent potential rivals from gaining power and threatening their position within the hybrid political regime. The theory suggests that the degree of political violence exerted by parties in hybrid regimes will increase (decrease) as they concentrate more (less) power in the legislature.MethodsUsing the methodology of analytical narratives, we examine the narrative on political violence in the Colombian political regime to identify key actors, strategies, information sets, and institutional changes. From these identified elements, we construct a theoretical model of political competition within the mathematical theory of games to explain the institutional changes highlighted in the narrative. Finally, we develop an econometric model to find statistical evidence supporting the predictions of the theoretical model derived from the narrative.ResultsThe narrative and the analytical narrative indicate that, in a hybrid regime, a higher degree of political power concentration causes a higher rate of political violence. The estimation of the Vector Auto-regression model allows us to analyze the response of the violence rate to a shock in the concentration index. Following an unexpected increase in the concentration of political power, the violence rate shows an initial increase of approximately 0.3 percentage points above its initial value. Subsequently, the effect attenuates slightly and stabilizes at around 0.2 percentage points above the baseline, maintaining this level throughout the period.Discussion/ConclusionThe theoretical model proposed in this paper suggests an explanation of political violence that diverges from the explanations offered by traditional theories. We suggest that the theoretical model proposed here captures the historical logic of the relationship between violence, political clientelism, and exclusion in Colombia, a country with a relatively long tradition as a formal democracy (since 1958), leading us to interesting conclusions that have not been proposed so far in the literature on violence in Latin America.

Mango is a popular tropical fruit that requires quarantine hot water treatment (QHWT) for postharvest sanitation, which can cause abiotic stress. Plants have various defense mechanisms to cope with stress; miRNAs mainly regulate the expression of these defense responses. Proteins involved in the biogenesis of miRNAs include DICER-like (DCL), ARGONAUTE (AGO), HYPONASTIC LEAVES 1 (HYL1), SERRATE (SE), HUA ENHANCER1 (HEN1), HASTY (HST), and HEAT-SHOCK PROTEIN 90 (HSP90), among others. According to our analysis, the mango genome contains five DCL, thirteen AGO, six HYL, two SE, one HEN1, one HST, and five putative HSP90 genes. Gene structure prediction and domain identification indicate that sequences contain key domains for their respective gene families, including the RNase III domain in DCL and PAZ and PIWI domains for AGOs. In addition, phylogenetic analysis indicates the formation of clades that include the mango sequences and their respective orthologs in other flowering plant species, supporting the idea these are functional orthologs. The analysis of cis-regulatory elements of these genes allowed the identification of MYB, ABRE, GARE, MYC, and MeJA-responsive elements involved in stress responses. Gene expression analysis showed that most genes are induced between 3 to 6 h after QHWT, supporting the early role of miRNAs in stress response. Interestingly, our results suggest that mango rapidly induces the production of miRNAs after heat stress. This research will enable us to investigate further the regulation of gene expression and its effects on commercially cultivated fruits, such as mango, while maintaining sanitary standards.

El presente artículo enfatiza en resaltar las vivencias de una persona que adquirió una discapacidad y que, en paralelo, utiliza la música como elemento para salvaguardar la vida y la salud. Esta investigación se llevó a cabo desde un enfoque cualitativo utilizando el método biográfico de historia de vida. La información se recopiló a través de una entrevista en la que se profundizó sobre la realidad que experimenta una persona con discapacidad motora y una encuesta sociodemográfica. Dentro de los resultados más significativos, se encontraron creencias persistentes frente a las personas con discapacidad motora, tales como la percepción de la discapacidad desde la pena, la lástima y la compasión. Además, se observó que estas personas a menudo desarrollan dependencia total o, en su defecto, son invisibilizadas por la sociedad. Esto refleja que aún se considera la discapacidad desde el modelo de prescindencia, un modelo que vulnera derechos.

El presente estudio buscó explorar los conocimientos e ideologías sobre multilingüismo y el grado de acceso e inclusión tienen los inmigrantes en la escuela pública chilena con base en la información entregada por profesores en formación y servicio del sistema educacional chileno. Para contestar estas preguntas se realizó una encuesta a 103 docentes, cuyos resultados se recogen en dos trabajos previos de Toledo et al. (2022a) y Toledo et al. (2022b), los cuales reunimos en este artículo, entregando un panorama completo de los hallazgos. Entre los hallazgos se encuentra una valoración positiva del multilingüismo por parte de los dos grupos de profesores, así como también la ausencia de lineamientos y formación para los profesores para enfrentar la interculturalidad y las aulas multilingües en el sistema educativo chileno actual.

Objetivo: Investigar las limitaciones, las barreras y las complicaciones en la transición del abordaje transesfenoidal microscópico (ATM) al abordaje endonasal endoscópico (AEE) para la base del cráneo en nuestra institución. Método: Se compararon las características clínicas y las complicaciones entre ATM, AEE y casos mixtos durante la curva quirúrgica temprana. Resultados: El periodo desde la curva de aprendizaje inicial fue de 1 año hasta que se utilizó el protocolo AEE de forma sistemática. Un total de 34 pacientes tuvieron una resección por vía transesfenoidal. A 18 pacientes se les realizó AEE, a 11 ATM y a 5 abordaje mixto endonasal y microscópico. Se encontraron diferencias no significativas en los resultados endocrinos entre los tres grupos. Los pacientes con función visual sin cambios o mejorada fueron más en el grupo AEE (p = 0.147). No se encontraron diferencias significativas respecto a la extensión de la resección (p = 0.369). Solo 1 (2.9%) paciente desarrolló una fístula de líquido cefalorraquídeo que se resolvió con manejo médico, perteneciente al grupo AEE (5.5%). Conclusiones: La fase inicial de la curva de aprendizaje no afectó significativamente a nuestra serie en términos de extensión de la resección, estado endocrino y resultados visuales.