Programs to improve body image in adolescents: A systematic review / Programas para mejorar la imagen corporal en adolescentes: una revisión sistemática

Abstract Objective: To examine the intervention programs that have been conducted on body image in adolescents. Materials and methods: The PRISMA statement was used in this review. The search for studies was conducted in PubMed, Web of Science, MEDLINE-ProQuest, and EBSCO databases from January 1, 2017, to January 25, 2022. Methodological quality was assessed using the Quality Assessment Tool for Quantitative Studies, developed by the Effective Public Health Practice Project. Results: Eight studies were included, most of which had a strong methodological quality. The results obtained after the implementation of the programs reflected favorable changes in body image and body satisfaction for adolescents between 11 and 18 years old, only for five studies. Additionally, five studies maintained the same changes at follow-up. Conclusions: Findings from this review allow us to conclude that intervention programs are a safe and effective way to influence adolescent body image.

Resumen Objetivo: Examinar los programas de intervención que se han realizado sobre imagen corporal en adolescentes. Materiales y métodos: En esta revisión se utilizó la declaración PRISMA. La búsqueda de los estudios se realizó en las bases de datos PubMed, Web of Science, MEDLINE-ProQuest y EBSCO, a partir del 1 enero de 2017 hasta el 25 de enero de 2022. La calidad metodológica se evaluó a través de la Quality Assessment Tool for Quantitative Studies, desarrollada por el Effective Public Health Practice Project. Resultados: Se incluyeron ocho estudios, de los cuales la mayoría tuvo una calidad metodológica fuerte. Los resultados obtenidos después de la implementación de los programas reflejaron cambios favorables en la imagen corporal y en satisfacción corporal para los adolescentes de entre 11 y 18 años, solo para cinco estudios. Adicionalmente, cinco estudios mantuvieron en el seguimiento los mismos cambios. Conclusiones: Los hallazgos de esta revisión nos permiten concluir que los programas de intervención, constituyen una forma segura y eficaz de incidir en la imagen corporal de los adolescentes.

One Earth: The Equilibrium between the Human and the Bacterial Worlds.

Misuse and abuse of antibiotics on humans, cattle, and crops have led to the selection of multi-resistant pathogenic bacteria, the most feared 'superbugs'. Infections caused by superbugs are progressively difficult to treat, with a subsequent increase in lethality: the toll on human lives is predicted to reach 10 million by 2050. Here we review three concepts linked to the growing resistance to antibiotics, namely (i) the Resistome, which refers to the collection of bacterial genes that confer resistance to antibiotics, (ii) the Mobilome, which includes all the mobile genetic elements that participate in the spreading of antibiotic resistance among bacteria by horizontal gene transfer processes, and (iii) the Nichome, which refers to the set of genes that are expressed when bacteria try to colonize new niches. We also discuss the strategies that can be used to tackle bacterial infections and propose an entente cordiale with the bacterial world so that instead of war and destruction of the 'fierce enemy' we can achieve a peaceful coexistence (the One Earth concept) between the human and the bacterial worlds. This, in turn, will contribute to microbial biodiversity, which is crucial in a globally changing climate due to anthropogenic activities.

Type II bacterial toxin-antitoxins: hypotheses, facts, and the newfound plethora of the PezAT system.

Toxin-antitoxin (TA) systems are entities found in the prokaryotic genomes, with eight reported types. Type II, the best characterized, is comprised of two genes organized as an operon. Whereas toxins impair growth, the cognate antitoxin neutralizes its activity. TAs appeared to be involved in plasmid maintenance, persistence, virulence, and defence against bacteriophages. Most Type II toxins target the bacterial translational machinery. They seem to be antecessors of Higher Eukaryotes and Prokaryotes Nucleotide-binding (HEPN) RNases, minimal nucleotidyltransferase domains, or CRISPR-Cas systems. A total of four TAs encoded by Streptococcus pneumoniae, RelBE, YefMYoeB, Phd-Doc, and HicAB, belong to HEPN-RNases. The fifth is represented by PezAT/Epsilon-Zeta. PezT/Zeta toxins phosphorylate the peptidoglycan precursors, thereby blocking cell wall synthesis. We explore the body of knowledge (facts) and hypotheses procured for Type II TAs and analyse the data accumulated on the PezAT family. Bioinformatics analyses showed that homologues of PezT/Zeta toxin are abundantly distributed among 14 bacterial phyla mostly in Proteobacteria (48%), Firmicutes (27%), and Actinobacteria (18%), showing the widespread distribution of this TA. The pezAT locus was found to be mainly chromosomally encoded whereas its homologue, the tripartite omega-epsilon-zeta locus, was found mostly on plasmids. We found several orphan pezT/zeta toxins, unaccompanied by a cognate antitoxin.

Risk Stratification to Guide Prevention and Control Strategies for Arboviruses Transmitted by Aedes aegypti.

Strategies for the prevention of arboviral diseases transmitted by Aedes aegypti have traditionally focused on vector control. This remains the same to this day, despite a lack of documented evidence on its efficacy due to a lack of coverage and sustainability. The continuous growth of urban areas and generally unplanned urbanization, which favor the presence of Ae. aegypti, demand resources, both material and human, as well as logistics to effectively lower the population's risk of infection. These considerations have motivated the development of tools to identify areas with a recurrent concentration of arboviral cases during an outbreak to be able to prioritize preventive actions and optimize available resources. This study explores the existence of spatial patterns of dengue incidence in the locality of Tartagal, in northeastern Argentina, during the outbreaks that occurred between 2010 and 2020. Approximately half (50.8%) of the cases recorded during this period were concentrated in 35.9% of the urban area. Additionally, an important overlap was found between hotspot areas of dengue and chikungunya (Kendall's W = 0.92; p-value < 0.001) during the 2016 outbreak. Moreover, 65.9% of the cases recorded in 2022 were geolocalized within the hotspot areas detected between 2010 and 2020. These results can be used to generate a risk map to implement timely preventive control strategies that prioritize these areas to reduce their vulnerability while optimizing the available resources and increasing the scope of action.

Alfabetización en medios para promover la satisfacción corporal y la alimentación saludable en adolescentes / Media literacy to promote body satisfaction and healthy eating in adolescents

Resumen Este estudio evaluó la eficacia de un programa de alfabetización en medios (AM) para promover la satisfacción corporal y la alimentación saludable en adolescentes de 12 a 15 años de edad. Es un estudio cuantitativo, cuasiexperimental y longitudinal, con preprueba y postprueba. Participaron 30 mujeres adolescentes de 12-15 años de edad, asignadas aleatoriamente a una de dos condiciones: programa de AM (n = 16) y grupo control en lista de espera (n = 14). Las participantes completaron, en preprueba y postprueba, el Cuestionario de Actitudes hacia la Apariencia Física (SATAQ-3), el Cuestionario de Evitación de la Imagen Corporal (BIAQ) y el Cuestionario de Comportamiento Alimentario (CCA). Hubo una disminución en las puntuaciones obtenidas por el grupo con intervención. Las participantes reportaron comparar menos su cuerpo con relación al cuerpo de las personas que son atléticas (F = 4.17, p = .05), las participantes también consideraron, al finalizar la intervención, que las personas famosas no son una fuente importante de información sobre la moda y sobre cómo ser atractiva (F = 6.87, p = .01). Los programas de AM son herramientas socioeducativas útiles para prevenir la insatisfacción corporal y los comportamientos alimentarios de riesgo, así como para promover conductas saludables.

Abstract This study evaluated the effectiveness of a media literacy (ML) program to promote body satisfaction and healthy eating in adolescents from 12 to 15 years old. The study is quantitative, quasi-experimental and longitudinal study, with pre-test and final post-test. Participated 30 female adolescents aged from 12 to 15 years old, randomly assigned to one of two conditions: ML program (n = 16) and control group on the waiting list (n = 14), who answered the Attitudes to the Physical Appearance Questionnaire (SATAQ-3), the Body Image Avoidance Questionnaire (BIAQ) and the Eating Behavior Questionnaire (CCA). The participants reported comparing their body less with respect to the body of people who are athletic (F = 4.17, p = .05), the participants also considered, at the end of the intervention, that famous people are not an important source of information about fashion and how to be attractive (F = 6.87, p = .01). ML programs are useful socio-educational tools to prevent problems such as dissatisfaction with body image and risky eating behaviors, or to promote healthy behaviors.

Promoter DNA recognition by the Enterococcus faecalis global regulator MafR.

When Enterococcus faecalis is exposed to changing environmental conditions, the expression of many genes is regulated at the transcriptional level. We reported previously that the enterococcal MafR protein causes genome-wide changes in the transcriptome. Here we show that MafR activates directly the transcription of the OG1RF_10478 gene, which encodes a hypothetical protein of 111 amino acid residues. We have identified the P10478 promoter and demonstrated that MafR enhances the efficiency of this promoter by binding to a DNA site that contains the -35 element. Moreover, our analysis of the OG1RF_10478 protein AlphaFold model indicates high similarity to 1) structures of EIIB components of the bacterial phosphoenolpyruvate:carbohydrate phosphotransferase system, and 2) structures of receiver domains that are found in response regulators of two-component signal transduction systems. However, unlike typical EIIB components, OG1RF_10478 lacks a Cys or His residue at the conserved phosphorylation site, and, unlike typical receiver domains, OG1RF_10478 lacks a conserved Asp residue at the position usually required for phosphorylation. Different from EIIB components and receiver domains, OG1RF_10478 contains an insertion between residues 10 and 30 that, according to ColabFold prediction, may serve as a dimerization interface. We propose that OG1RF_10478 could participate in regulatory functions by protein-protein interactions.

PclR is a transcriptional activator of the gene that encodes the pneumococcal collagen-like protein PclA.

The Gram-positive bacterium Streptococcus pneumoniae is a major human pathogen that shows high levels of genetic variability. The pneumococcal R6 genome harbours several gene clusters that are not present in all strains of the species. One of these clusters contains two divergent genes, pclA, which encodes a putative surface-exposed protein that contains large regions of collagen-like repeats, and spr1404 (here named pclR). PclA was shown to mediate pneumococcal adherence to host cells in vitro. In this work, we demonstrate that PclR (494 amino acids) is a transcriptional activator. It stimulates transcription of the pclA gene by binding to a specific DNA site upstream of the core promoter. In addition, we show that PclR has common features with the MgaSpn transcriptional regulator (493 amino acids), which is also encoded by the R6 genome. These proteins have high sequence similarity (60.3%), share the same organization of predicted functional domains, and generate multimeric complexes on linear double-stranded DNAs. However, on the PpclA promoter region, MgaSpn binds to a site different from the one recognized by PclR. Our results indicate that PclR and MgaSpn have similar DNA-binding properties but different DNA-binding specificities, pointing to a different regulatory role of both proteins.

Where to From Here?

The biological-biochemical community has been shocked and delighted by the remarkable progress that has recently been made on a problem that has consumed the attention, energy, and resources of many, if not most of the scientists in the field for the past 50 years. The problem has been to predict the tertiary structure of a protein merely from its amino acid sequence. Nature does it easily enough, but it has been an incredibly difficult problem, often considered intractable, for humankind. The breakthrough has come in the form of two computer-based approaches, AlphaFold2 and RoseTTAFold in conjunction with factors such as the use of vast computing power, the field of artificial intelligence, and the existence of huge protein sequence databases. The advancement of these tools depended upon and was stimulated by the last 50 years of development of smaller and smaller and more and more powerful electronics components, mainly processors and memory. Along with the problem of protein folding, determining the function or mechanism of action of proteins has similarly limped along as did protein folding until the recent breakthroughs. Perhaps AlphaFold2 and RoseTTAFold can substantially aid in protein mechanistic studies. Now it is not completely insane to consider what might be the next grand challenge in biochemistry-biology. We offer several possibilities.

The Facts and Family Secrets of Plasmids That Replicate via the Rolling-Circle Mechanism.

Plasmids are self-replicative DNA elements that are transferred between bacteria. Plasmids encode not only antibiotic resistance genes but also adaptive genes that allow their hosts to colonize new niches. Plasmid transfer is achieved by conjugation (or mobilization), phage-mediated transduction, and natural transformation. Thousands of plasmids use the rolling-circle mechanism for their propagation (RCR plasmids). They are ubiquitous, have a high copy number, exhibit a broad host range, and often can be mobilized among bacterial species. Based upon the replicon, RCR plasmids have been grouped into several families, the best known of them being pC194 and pUB110 (Rep_1 family), pMV158 and pE194 (Rep_2 family), and pT181 and pC221 (Rep_trans family). Genetic traits of RCR plasmids are analyzed concerning (i) replication mediated by a DNA-relaxing initiator protein and its interactions with the cognate DNA origin, (ii) lagging-strand origins of replication, (iii) antibiotic resistance genes, (iv) mobilization functions, (v) replication control, performed by proteins and/or antisense RNAs, and (vi) the participating host-encoded functions. The mobilization functions include a relaxase initiator of transfer (Mob), an origin of transfer, and one or two small auxiliary proteins. There is a family of relaxases, the MOBV family represented by plasmid pMV158, which has been revisited and updated. Family secrets, like a putative open reading frame of unknown function, are reported. We conclude that basic research on RCR plasmids is of importance, and our perspectives contemplate the concept of One Earth because we should incorporate bacteria into our daily life by diminishing their virulence and, at the same time, respecting their genetic diversity.

Learning-by-Teaching Approach Improves Dengue Knowledge in Children and Parents.

There is narrow evidence on which strategies are most effective for disseminating information on dengue prevention. This is particularly relevant because social habits have a great prevention capacity for dengue. We investigated how effective are children as health educators, and how much they learn as they teach. We recruited 142 children and 97 parents in Argentina's tropical area for two cluster randomized parallel trials. In Study 1, we compared the dynamics of dengue knowledge of 10-year-old children who-after receiving a dengue talk-1) listened to an unrelated topic; 2) read a booklet with information about dengue, 3) taught their parents about dengue, or 4) taught their parents about dengue, using the booklet. In Study 2, we assessed whether the parents' dengue knowledge changed after interacting with their children, in comparison with parents learning about dengue from an expert or about an unrelated topic. Children that taught their parents what they learned, using a booklet, showed 2.53 more correct responses (95% CI [0.20, 4.85]; P = 0.027) than children who listened to an unrelated topic. This style of teaching also serves to effectively propagate knowledge: parents learned from their children the same as from an expert; and significantly more than parents who learned about an unrelated topic. Parents learned from their children even if they were taught with booklets (1.49, 95% CI [0.01, 2.96]; P = 0.048) or without (1.94, 95% CI [0.44, 3.44]; P = 0.006). Specifically, after being taught by their children, parents showed on average 1.49 (if they were taught with a booklet) and 1.94 (without booklet) more correct responses than parents that learned about an unrelated topic. The simple action of prompting children to teach consolidated their own knowledge and broadcasted it effectively to their parents. This strategy is a potential low to no-cost method for sharing information about dengue prevention.

Recognition of Streptococcal Promoters by the Pneumococcal SigA Protein.

Promoter recognition by RNA polymerase is a key step in the regulation of gene expression. The bacterial RNA polymerase core enzyme is a complex of five subunits that interacts transitory with one of a set of sigma factors forming the RNA polymerase holoenzyme. The sigma factor confers promoter specificity to the RNA polymerase. In the Gram-positive pathogenic bacterium Streptococcus pneumoniae, most promoters are likely recognized by SigA, a poorly studied housekeeping sigma factor. Here we present a sequence conservation analysis and show that SigA has similar protein architecture to Escherichia coli and Bacillus subtilis homologs, namely the poorly conserved N-terminal 100 residues and well-conserved rest of the protein (domains 2, 3, and 4). Further, we have purified the native (untagged) SigA protein encoded by the pneumococcal R6 strain and reconstituted an RNA polymerase holoenzyme composed of the E. coli core enzyme and the sigma factor SigA (RNAP-SigA). By in vitro transcription, we have found that RNAP-SigA was able to recognize particular promoters, not only from the pneumococcal chromosome but also from the S. agalactiae promiscuous antibiotic-resistance plasmid pMV158. Specifically, SigA was able to direct the RNA polymerase to transcribe genes involved in replication and conjugative mobilization of plasmid pMV158. Our results point to the versatility of SigA in promoter recognition and its contribution to the promiscuity of plasmid pMV158.

Interactions of the Streptococcus pneumoniae Toxin-Antitoxin RelBE Proteins with Their Target DNA.

Type II bacterial toxin-antitoxin (TA) systems are found in most bacteria, archaea, and mobile genetic elements. TAs are usually found as a bi-cistronic operon composed of an unstable antitoxin and a stable toxin that targets crucial cellular functions like DNA supercoiling, cell-wall synthesis or mRNA translation. The type II RelBE system encoded by the pathogen Streptococcus pneumoniae is highly conserved among different strains and participates in biofilm formation and response to oxidative stress. Here, we have analyzed the participation of the RelB antitoxin and the RelB:RelE protein complex in the self-regulation of the pneumococcal relBE operon. RelB acted as a weak repressor, whereas RelE performed the role of a co-repressor. By DNA footprinting experiments, we show that the proteins bind to a region that encompasses two palindromic sequences that are located around the -10 sequences of the single promoter that directs the synthesis of the relBE mRNA. High-resolution footprinting assays showed the distribution of bases whose deoxyriboses are protected by the bound proteins, demonstrating that RelB and RelB:RelE contacted the DNA backbone on one face of the DNA helix and that these interactions extended beyond the palindromic sequences. Our findings suggest that the binding of the RelBE proteins to its DNA target would lead to direct inhibition of the binding of the host RNA polymerase to the relBE promoter.

El conocimiento sobre métodos anticonceptivos y la conducta sexual en jóvenes universitarios / Training in mental health in psychology, social work, medicine, nursing and occupational therapy in colombia / O conhecimento sobre métodos anticonceptivos e a conduta sexual em jovens universitarios

Introducción: En México los embarazos no planificados se presentan entre 30% y 60% en adolescentes. Esta problemática permea a todos los grupos de la sociedad observándose aún en las universidades. La Universidad Autónoma del Estado de México ha realizado acciones preventivas; sin embargo, en cinco años, el número de embarazos en las estudiantes incrementó en un plantel de la zona oriente, por lo que se propuso evaluar el conocimiento sobre métodos de planificación familiar y conducta sexual que tienen los estudiantes universitarios. Metodología: Estudio cuantitativo transversal realizado en 2018. La muestra no probabilística estuvo integrada por 224 alumnos de ciencias sociales del nivel superior de la Universidad Autónoma del Estado de México, quienes dieron su consentimiento informado. Se les aplicó un cuestionario de 32 ítems a través del cual se evaluó conocimiento sobre métodos de planificación familiar y conductas sexuales que tenían. Resultados: 51% informaron recibir información sobre métodos de planificación familiar entre 13 y 17 años, proviniendo de su profesor(a). 69% de los estudiantes reportaron haber tenido relaciones sexuales; de los cuales 97% respondieron que antes de ingresar al nivel superior recibieron la información sobre métodos anticonceptivos. Actualmente 45% no utiliza algún método anticonceptivo, 49% declararon haber tenido sexo oral y 18% anal. 9% reportó tener relaciones sexuales bajo influencia de drogas. Conclusiones: Se realizó un acercamiento al conocimiento sobre métodos de planificación familiar y conducta sexual de los estudiantes, para diseñar e implementar un programa de salud sexual que prevenga infecciones de transmisión sexual y embarazos no planificados.

Unplanned pregnancies in Mexico occur between 30 and 60 percent of the cases in adolescents. This problem permeates all groups in society being observed even in universities. Universidad Autónoma del Estado de Mexico has developed preventive actions, but in five years the number of pregnancies in students increased in one of its campuses in the western area, reason why it was proposed to evaluate the knowledge about family planning methods and sexual behavior that university students have. Methodology: Cross-sectional quantitative study conducted in 2018. The non-probability sample consisted of 224 students from the upper level of Universidad Autónoma del Estado de Mexico who gave their informed consent. A questionnaire of 32 items was applied, through which knowledge about family planning methods and sexual behaviors they had were evaluated. Results: 51% reported receiving information about family planning methods when they were 13 and 17 years old, coming from their teachers. 69% of the students reported having had sexual intercourse from whom 97% answered that they had received information about contraceptive methods before entering the upper level. Currently 45% do not use any contraception method, 49% reported having oral sex and 18% anal sex; 9% reported having sex under the influence of drugs. Conclusions: An approach was made to knowledge about family planning methods and sexual behavior of students, to design and implement a sexual health program that prevents sexually transmitted infections and unplanned pregnancies.

Introdução: No México a gravidez não planificados se apresentam entre 30% e 60% em adolescentes. Esta problemática permeia a todos os grupos da sociedade observando-se ainda nas universidades. A Universidade Autônoma do Estado do México tem realizado ações preventivas; porém, em cinco anos, o número de gravidezes nas estudantes incrementou num campus da zona oriente, pelo que se propus avaliar o conhecimento sobre métodos de planificação familiar e conduta sexual que têm os estudantes universitários. Metodologia: Estudo quantitativo transversal realizado em 2018. A amostra não probabilística esteve integrada por 224 alunos de ciências sociais do nível superior da Universidade Autônoma do Estado de México, quem deram seu consentimento informado. Aplicou-se lhes um questionário de 32 itens a través do qual se avaliou conhecimento sobre métodos de planificação familiar e condutas sexuais que tinham. Resultados: 51% informaram receber informação sobre métodos de planificação familiar entre 13 e 17 anos, prevenindo do seu professor(a). 69% dos estudantes reportaram ter tido relações sexuais; dos quais 97% responderam que antes de ingressar ao nível superior receberam a informação sobre métodos anticonceptivos. Atualmente 45% não utiliza algum método anticonceptivo, 49% declararam ter tido sexo oral e 18% anal. 9% aceitaram ter relaciones sexuais sob efeito das drogas. Conclusões: Realizou-se uma aproximação ao conhecimento sobre métodos de planificação familiar e conduta sexual dos estudantes, para desenhar e dar execução a um programa de saúde sexual que evite infeções de transmissão sexual e gravidez não planificados

El conocimiento sobre métodos anticonceptivos y la conducta sexual en jóvenes universitarios / Knowledge about contraceptive methods and sexual behavior in young university students / O conhecimento sobre métodos anticonceptivos e a conduta sexual em jovens universitários

Resumen Introducción: En México los embarazos no planificados se presentan entre 30% y 60% en adolescentes. Esta problemática permea a todos los grupos de la sociedad observándose aún en las universidades. La Universidad Autónoma del Estado de México ha realizado acciones preventivas; sin embargo, en cinco años, el número de embarazos en las estudiantes incrementó en un plantel de la zona oriente, por lo que se propuso evaluar el conocimiento sobre métodos de planificación familiar y conducta sexual que tienen los estudiantes universitarios. Metodología: Estudio cuantitativo transversal realizado en 2018. La muestra no probabilística estuvo integrada por 224 alumnos de ciencias sociales del nivel superior de la Universidad Autónoma del Estado de México, quienes dieron su consentimiento informado. Se les aplicó un cuestionario de 32 ítems a través del cual se evaluó conocimiento sobre métodos de planificación familiar y conductas sexuales que tenían. Resultados: 51% informaron recibir información sobre métodos de planificación familiar entre 13 y 17 años, proviniendo de su profesor(a). 69% de los estudiantes reportaron haber tenido relaciones sexuales; de los cuales 97% respondieron que antes de ingresar al nivel superior recibieron la información sobre métodos anticonceptivos. Actualmente 45% no utiliza algún método anticonceptivo, 49% declararon haber tenido sexo oral y 18% anal. 9% reportó tener relaciones sexuales bajo influencia de drogas. Conclusiones: Se realizó un acercamiento al conocimiento sobre métodos de planificación familiar y conducta sexual de los estudiantes, para diseñar e implementar un programa de salud sexual que prevenga infecciones de transmisión sexual y embarazos no planificados.

Abstract Introduction: Unplanned pregnancies in Mexico occur between 30 and 60 percent of the cases in adolescents. This problem permeates all groups in society being observed even in universities. Universidad Autónoma del Estado de Mexico has developed preventive actions, but in five years the number of pregnancies in students increased in one of its campuses in the western area, reason why it was proposed to evaluate the knowledge about family planning methods and sexual behavior that university students have. Methodology: Cross-sectional quantitative study conducted in 2018. The non-probability sample consisted of 224 students from the upper level of Universidad Autónoma del Estado de Mexico who gave their informed consent. A questionnaire of 32 items was applied, through which knowledge about family planning methods and sexual behaviors they had were evaluated. Results: 51% reported receiving information about family planning methods when they were 13 and 17 years old, coming from their teachers. 69% of the students reported having had sexual intercourse from whom 97% answered that they had received information about contraceptive methods before entering the upper level. Currently 45% do not use any contraception method, 49% reported having oral sex and 18% anal sex; 9% reported having sex under the influence of drugs. Conclusions: An approach was made to knowledge about family planning methods and sexual behavior of students, to design and implement a sexual health program that prevents sexually transmitted infections and unplanned pregnancies.

Resumo Introdução: No México a gravidez não planificados se apresentam entre 30% e 60% em adolescentes. Esta problemática permeia a todos os grupos da sociedade observando-se ainda nas universidades. A Universidade Autônoma do Estado do México tem realizado ações preventivas; porém, em cinco anos, o número de gravidezes nas estudantes incrementou num campus da zona oriente, pelo que se propus avaliar o conhecimento sobre métodos de planificação familiar e conduta sexual que têm os estudantes universitários. Metodologia: Estudo quantitativo transversal realizado em 2018. A amostra não probabilística esteve integrada por 224 alunos de ciências sociais do nível superior da Universidade Autônoma do Estado de México, quem deram seu consentimento informado. Aplicou-se lhes um questionário de 32 itens a través do qual se avaliou conhecimento sobre métodos de planificação familiar e condutas sexuais que tinham. Resultados: 51% informaram receber informação sobre métodos de planificação familiar entre 13 e 17 anos, prevenindo do seu professor(a). 69% dos estudantes reportaram ter tido relações sexuais; dos quais 97% responderam que antes de ingressar ao nível superior receberam a informação sobre métodos anticonceptivos. Atualmente 45% não utiliza algum método anticonceptivo, 49% declararam ter tido sexo oral e 18% anal. 9% aceitaram ter relaciones sexuais sob efeito das drogas. Conclusões: Realizou-se uma aproximação ao conhecimento sobre métodos de planificação familiar e conduta sexual dos estudantes, para desenhar e dar execução a um programa de saúde sexual que evite infeções de transmissão sexual e gravidez não planificados.

In vitro DNA Inversions Mediated by the PsrA Site-Specific Tyrosine Recombinase of Streptococcus pneumoniae.

Site-specific recombination is a DNA breaking and reconstructing process that plays important roles in various cellular pathways for both prokaryotes and eukaryotes. This process requires a site-specific recombinase and direct or inverted repeats. Some tyrosine site-specific recombinases catalyze DNA inversions and regulate subpopulation diversity and phase variation in many bacterial species. In Streptococcus pneumoniae, the PsrA tyrosine recombinase was shown to control DNA inversions in the three DNA methyltransferase hsdS genes of the type I restriction-modification cod locus. Such DNA inversions are mediated by three inverted repeats (IR1, IR2, and IR3). In this work, we purified an untagged form of the PsrA protein and studied its DNA-binding and catalytic features. Gel retardation assays showed that PsrA binds to linear and supercoiled DNAs, containing or not inverted repeats. Nevertheless, DNase I footprinting assays showed that, on linear DNAs, PsrA has a preference for sites that include an IR1 sequence (IR1.1 or IR1.2) and its boundary sequences. Furthermore, on supercoiled DNAs, PsrA was able to generate DNA inversions between specific inverted repeats (IR1, IR2, and IR3), which supports its ability to locate specific target sites. Unlike other site-specific recombinases, PsrA showed reliance on magnesium ions for efficient catalysis of IR1-mediated DNA inversions. We discuss that PsrA might find its specific binding sites on the bacterial genome by a mechanism that involves transitory non-specific interactions between protein and DNA.

Complete labelling of pneumococcal DNA-binding proteins with seleno-L-methionine.

Streptococcus pneumoniae is a pathogenic and opportunistic Gram-positive bacterium that is the leading cause of community-acquired respiratory diseases, varying from mild- to deathly- infections. The appearance of antibiotic-resistant isolates has prompted the search for novel strategies and targets to tackle the bacterial resistances. One of the most promising approaches is the structure-based knowledge of possible targets in conjunction with rational design and docking of inhibitors of the chosen targets. A useful technique that helps to solve protein structures is to label them with an amino acid derivative like seleno-methionine that facilitates tracing of some of the amino acid residues. We have chosen two pneumococcal DNA-binding proteins, namely the relaxase domain of MobM protein from plasmid pMV158, and the RelB-RelE antitoxin-toxin protein complex. Through several changes that improve substantially a previous protocol (Budisa et al., 1995), we have used seleno-L-methionine to incorporate selenium into the amino acid sequence of the selected proteins. We have achieved 100% labelling of the proteins and could demonstrate that the labelled proteins retained full activity as judged from the relaxation of supercoiled plasmid DNA and from gel-retardation assays.

Transcriptional activation by MafR, a global regulator of Enterococcus faecalis.

Proteins that act as global transcriptional regulators play key roles in bacterial adaptation to new niches. These proteins recognize multiple DNA sites across the bacterial genome by different mechanisms. Enterococcus faecalis is able to survive in various niches of the human host, either as a commensal or as a leading cause of serious infections. Nonetheless, the regulatory pathways involved in its adaptive responses remain poorly understood. We reported previously that the MafR protein of E. faecalis causes genome-wide changes in the transcriptome. Here we demonstrate that MafR functions as a transcription activator. In vivo, MafR increased the activity of the P12294 and P11486 promoters and also the transcription levels of the two genes controlled by those promoters. These genes are predicted to encode a calcium-transporting P-type ATPase and a QueT transporter family protein, respectively. Thus, MafR could have a regulatory role in calcium homeostasis and queuosine synthesis. Furthermore, MafR recognized in vitro specific DNA sites that overlap the -35 element of each target promoter. The MafR binding sites exhibit a low sequence identity, suggesting that MafR uses a shape readout mechanism to achieve DNA-binding specificity.

Operational satellite-based temporal modelling of Aedes population in Argentina.

Aedes aegypti is a vector for Chikungunya, Dengue and Zika viruses in Latin America and is therefore a large public health problem for the region. For this reason, several inter-institutional and multidisciplinary efforts have been made to support vector control actions through the use of geospatial technologies. This study presents the development of an operational system for the application of free access to remotely sensed products capable of assessing the oviposition activity of Ae. aegypti in all of Argentina's northern region with the specific aim to improve the current Argentine National Dengue risk system. Temporal modelling implemented includes remotely sensed variables like the normalized difference vegetation index, the normalized difference water index, day and night land surface temperature and precipitation data available from NASA's tropical rainfall measuring mission and global precipitation measurement. As a training data set, four years of weekly mosquito oviposition data from four different cities in Argentina were used. A series of satellite-generated variables was built, downloading and resampling the these products both spatially and temporally. From an initial set of 41 variables chosen based on the correlation between these products and the oviposition series, a subset of 11 variables were preserved to develop temporal forecasting models of oviposition using a lineal multivariate method in the four cities. Subsequently, a general model was generated using data from the cities. Finally, in order to obtain a model that could be broadly used, an extrapolation method using the concept of environmental distance was developed. Although the system was oriented towards the surveillance of dengue fever, the methodology could also be applied to other relevant vector-borne diseases as well as other geographical regions in Latin America.