Self-Efficacy and Well-Being in Professionals Working in Intimate Partner Violence: Recovery Experiences and Burnout as Associated Variables.

The negative consequences of intimate partner violence against women (IPVAW) are observed not only in the victims but also in the professionals who work in this field. Self-efficacy has been observed as a significant variable in the perception of work efficiency and general well-being, and in coping with work-related stress and burnout syndrome. Thus, we performed a correlational study (N = 200) to examine the mediating role of recovery experiences and emotional exhaustion in the relationship between self-efficacy and psychological well-being in these professionals. The mediating analyses revealed that self-efficacy was related to higher levels of well-being through its effects on the increase in recovery experiences and the decrease in burnout levels. These findings emphasize the need to develop intervention programs aimed at improving self-efficacy these professionals. This is necessary to improve their employment situations, increase their health, and optimize both institutional resources and the quality of the services offered.

#Instacomparison: Social Comparison and Envy as Correlates of Exposure to Instagram and Cyberbullying Perpetration.

Instagram is a popular social networking site (SNS) among adolescents that allows them to share visual content about their lives quickly and easily, increasing social connection, acceptation, and entertainment among others. Nevertheless, SNS exposure can also lead to negative counterparts such as judgments, envy, social comparison, or cyberbullying perpetration. This research aimed to analyze the possible psychosocial factors associated with Instagram use (i.e., social comparison and envy) that could lead to the perpetration of cyberbullying towards peers. The sample consisted of 254 adolescent students aged between 15 and 18 years old (Mage = 15.77, SD = 0.74). The results indicated that high connection time to Instagram, high levels of social comparison, and malicious envy were associated with an increased tendency to carry out cyberbullying perpetration's behaviors. Likewise, the main finding showed that a high connection time to Instagram was associated with increased social comparison, which in turn was associated with malicious envy, and consequently with an increased tendency to carry out cyberbullying perpetration's behaviors. These findings contribute to a better understanding of the psychosocial processes that might precede to perpetrate cyberbullying's behaviors, as well as to promote the development of educational programs intend to encourage the responsible use of SNSs during adolescence.

Does the Number of Likes Affect Adolescents' Emotions? The Moderating Role of Social Comparison and Feedback-Seeking on Instagram.

Instagram is a social networking site (SNS) that facilitate the social-comparison and feedback-seeking (SCFS) processes, which are particularly relevant during adolescence. Likes represent numeric evaluative feedback and seem to be considered as a form of social reward. In this research we examine some psychosocial factors that could influence the Instagram usage intensity (i.e. SCFS and motivations) and analyze the moderating role of SCFS in the relationship between the number of likes on posts and adolescents' emotions. The sample consisted of 182 adolescent students aged between 13 and 18 years (M = 15.35 years, SD = 1.11). The results show that the social interaction, storage, and gossip motivations mediate the relationship between SCFS and Instagram usage intensity, and that the influence of the number of likes on emotions depended on the degree of SCFS. The discussion of the findings emphasizes that likes have a special social and affective relevance for adolescents with high SCFS, who might become more emotionally susceptible to the feedback they received from their audience on Instagram. This research could be a precedent to future research and the development of intervention programs based on the responsible use of SNSs in an educative context.

A reconstituted system reveals how activating and inhibitory interactions control DDK dependent assembly of the eukaryotic replicative helicase.

During G1-phase of the cell-cycle the replicative MCM2-7 helicase becomes loaded onto DNA into pre-replicative complexes (pre-RCs), resulting in MCM2-7 double-hexamers on DNA. In S-phase, Dbf4-dependent kinase (DDK) and cyclin-dependent-kinase (CDK) direct with the help of a large number of helicase-activation factors the assembly of a Cdc45-MCM2-7-GINS (CMG) complex. However, in the absence of S-phase kinases complex assembly is inhibited, which is unexpected, as the MCM2-7 double-hexamer represents a very large interaction surface. Currently it is unclear what mechanisms restricts complex assembly and how DDK can overcome this inhibition to promote CMG-assembly. We developed an advanced reconstituted-system to study helicase activation in-solution and discovered that individual factors like Sld3 and Sld2 can bind directly to the pre-RC, while Cdc45 cannot. When Sld3 and Sld2 were incubated together with the pre-RC, we observed that competitive interactions restrict complex assembly. DDK stabilizes the Sld3/Sld2-pre-RC complex, but the complex is only short-lived, indicating an anti-cooperative mechanism. Yet, a Sld3/Cdc45-pre-RC can form in the presence of DDK and the addition of Sld2 enhances complex stability. Our results indicate that helicase activation is regulated by competitive and cooperative interactions, which restrict illegitimate complex formation and direct limiting helicase-activation factors into pre-initiation complexes.

Spanish adaptation of the Illinois sexual harassment myth acceptance

Sexual harassment is among the most serious forms of gender violence, and what all violent acts have in common are the many myths associated with them. Three studies were conducted to adapt a Spanish version of the Illinois Sexual Harassment Myth Acceptance (ISHMA) scale, which assesses myths about sexual harassment. The first study aimed to, for the first time, present psychometric data on the Spanish version of the ISHMA. The participants were 339 college students. After adapting the items and measuring their content validity, we examined the test’s dimensional structure, statistically analyzed the items, and determined the instrument’s reliability (α = .91 for the total scale and between .77 and .84 for the different dimensions). Study 2 involved 326 adult participants from the general population and its objective was to evaluate the scale’s dimensional structure through confirmatory factor analysis (χ2 143 = 244.860, p < .001; GFI = .952; CFI = .958; RMSEA = .034 [.026 - .041]). The third study was conducted in order to measure convergent validity in both students and adults from the general population. Differences by gender were found in all dimensions being the females' means higher than males (Cohen's d between .38 and .62). Our findings suggest the Spanish version of the ISHMA is a useful instrument to study myths about sexual harassment (AU)

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Stop Harassment Men's reactions to victims' confrontation / ¡Stop Acoso! Reacciones de los hombres a la confrontación de las víctimas

Sexual harassment is one of the most widespread forms of gender violence. Perceptions of sexual harassment depend on gender, context, the perceivers' ideology, and a host of other factors. Research has underscored the importance of coping strategies in raising a victim's self-confidence by making her feel that she plays an active role in overcoming her own problems. The aim of this study was to assess the men's perceptions of sexual harassment in relation to different victim responses. The study involved 101 men who were administered a questionnaire focusing on two of the most frequent types of harassment (gender harassment vs. unwanted sexual attention) and victim response (confrontation vs. non confrontation), both of which were manipulated. Moreover, the influences of ideological variables, ambivalent sexism, and the acceptance of myths of sexual harassment on perception were also assessed. The results highlight the complexities involved in recognizing certain behaviors as harassment and the implications of different victim responses to incidents of harassment. As the coping strategies used by women to confront harassment entail drawbacks that pose problems or hinder them, the design and implementation of prevention and/or education programs should strive to raise awareness among men and women to further their understanding of this construct (AU)

El acoso sexual es una de las formas más generalizadas de violencia de género. Las percepciones sobre el acoso sexual dependen de factores tales como el género, el contexto y la ideología del perceptor, entre otros. La investigación ha mostrado la importancia que tiene el afrontamiento de la víctima en su nivel de confianza, haciendo que sienta de esta manera que tiene un papel relevante en la solución del problema. El objetivo de este estudio fue indagar en la percepción que los hombres tienen acerca del acoso sexual y de las distintas medidas usadas como respuesta por parte de la víctima. Participaron en el estudio 101 hombres que contestaron un cuestionario en el que se manipulaban dos de los tipos de acoso más frecuentes (acoso de género vs. atención sexual no deseada) así como la respuesta de la víctima (confrontación vs. no confrontación). También se estudió la influencia en dicha percepción de variables ideológicas como el sexismo ambivalente y la aceptación de los mitos sobre el acoso sexual. Los resultados resaltan la dificultad de reconocer determinados comportamientos como acoso, así como las posibles consecuencias que puede sufrir la víctima en función de la respuesta que dé a estas situaciones de acoso. Las estrategias usadas por las mujeres para afrontar el acoso parecen presentar algún obstáculo o problema para ellas, por lo que se hace necesaria la implantación de programas preventivos y/o educativos con el fin de enseñar a hombres y mujeres a comprender mejor el constructo (AU)

A unique DNA entry gate serves for regulated loading of the eukaryotic replicative helicase MCM2-7 onto DNA.

The regulated loading of the replicative helicase minichromosome maintenance proteins 2-7 (MCM2-7) onto replication origins is a prerequisite for replication fork establishment and genomic stability. Origin recognition complex (ORC), Cdc6, and Cdt1 assemble two MCM2-7 hexamers into one double hexamer around dsDNA. Although the MCM2-7 hexamer can adopt a ring shape with a gap between Mcm2 and Mcm5, it is unknown which Mcm interface functions as the DNA entry gate during regulated helicase loading. Here, we establish that the Saccharomyces cerevisiae MCM2-7 hexamer assumes a closed ring structure, suggesting that helicase loading requires active ring opening. Using a chemical biology approach, we show that ORC-Cdc6-Cdt1-dependent helicase loading occurs through a unique DNA entry gate comprised of the Mcm2 and Mcm5 subunits. Controlled inhibition of DNA insertion triggers ATPase-driven complex disassembly in vitro, while in vivo analysis establishes that Mcm2/Mcm5 gate opening is essential for both helicase loading onto chromatin and cell cycle progression. Importantly, we demonstrate that the MCM2-7 helicase becomes loaded onto DNA as a single hexamer during ORC/Cdc6/Cdt1/MCM2-7 complex formation prior to MCM2-7 double hexamer formation. Our study establishes the existence of a unique DNA entry gate for regulated helicase loading, revealing key mechanisms in helicase loading, which has important implications for helicase activation.

Spanish adaptation of the Illinois Sexual Harassment Myth Acceptance.

Sexual harassment is among the most serious forms of gender violence, and what all violent acts have in common are the many myths associated with them. Three studies were conducted to adapt a Spanish version of the Illinois Sexual Harassment Myth Acceptance (ISHMA) scale, which assesses myths about sexual harassment. The first study aimed to, for the first time, present psychometric data on the Spanish version of the ISHMA. The participants were 339 college students. After adapting the items and measuring their content validity, we examined the test's dimensional structure, statistically analyzed the items, and determined the instrument's reliability (α = .91 for the total scale and between .77 and .84 for the different dimensions). Study 2 involved 326 adult participants from the general population and its objective was to evaluate the scale's dimensional structure through confirmatory factor analysis (χ2 143 = 244.860, p < .001; GFI = .952; CFI = .958; RMSEA = .034 [.026 - .041]). The third study was conducted in order to measure convergent validity in both students and adults from the general population. Differences by gender were found in all dimensions being the females' means higher than males (Cohen´s d between .38 and .62). Our findings suggest the Spanish version of the ISHMA is a useful instrument to study myths about sexual harassment.

Recaída de síndrome nefrótico por enfermedad de cambios mínimos tras administración de bevacizumab intravítreo / Relapse of minimal change disease nephrotic syndrome after administering intravitreal bevacizumab

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The ORC/Cdc6/MCM2-7 complex facilitates MCM2-7 dimerization during prereplicative complex formation.

The replicative mini-chromosome-maintenance 2-7 (MCM2-7) helicase is loaded in Saccharomyces cerevisiae and other eukaryotes as a head-to-head double-hexamer around origin DNA. At first, ORC/Cdc6 recruits with the help of Cdt1 a single MCM2-7 hexamer to form an 'initial' ORC/Cdc6/Cdt1/MCM2-7 complex. Then, on ATP hydrolysis and Cdt1 release, the 'initial' complex is transformed into an ORC/Cdc6/MCM2-7 (OCM) complex. However, it remains unclear how the OCM is subsequently converted into a MCM2-7 double-hexamer. Through analysis of MCM2-7 hexamer-interface mutants we discovered a complex competent for MCM2-7 dimerization. We demonstrate that these MCM2-7 mutants arrest during prereplicative complex (pre-RC) assembly after OCM formation, but before MCM2-7 double-hexamer assembly. Remarkably, only the OCM complex, but not the 'initial' ORC/Cdc6/Cdt1/MCM2-7 complex, is competent for MCM2-7 dimerization. The MCM2-7 dimer, in contrast to the MCM2-7 double-hexamer, interacts with ORC/Cdc6 and is salt-sensitive, classifying the arrested complex as a helicase-loading intermediate. Accordingly, we found that overexpression of the mutants cause cell-cycle arrest and dominant lethality. Our work identifies the OCM complex as competent for MCM2-7 dimerization, reveals MCM2-7 dimerization as a limiting step during pre-RC formation and defines critical mechanisms that explain how origins are licensed.

An ORC/Cdc6/MCM2-7 complex is formed in a multistep reaction to serve as a platform for MCM double-hexamer assembly.

In Saccharomyces cerevisiae and higher eukaryotes, the loading of the replicative helicase MCM2-7 onto DNA requires the combined activities of ORC, Cdc6, and Cdt1. These proteins load MCM2-7 in an unknown way into a double hexamer around DNA. Here we show that MCM2-7 recruitment by ORC/Cdc6 is blocked by an autoinhibitory domain in the C terminus of Mcm6. Interestingly, Cdt1 can overcome this inhibitory activity, and consequently the Cdt1-MCM2-7 complex activates ORC/Cdc6 ATP-hydrolysis to promote helicase loading. While Cdc6 ATPase activity is known to facilitate Cdt1 release and MCM2-7 loading, we discovered that Orc1 ATP-hydrolysis is equally important in this process. Moreover, we found that Orc1/Cdc6 ATP-hydrolysis promotes the formation of the ORC/Cdc6/MCM2-7 (OCM) complex, which functions in MCM2-7 double-hexamer assembly. Importantly, CDK-dependent phosphorylation of ORC inhibits OCM establishment to ensure once per cell cycle replication. In summary, this work reveals multiple critical mechanisms that redefine our understanding of DNA licensing.

In the absence of ATPase activity, pre-RC formation is blocked prior to MCM2-7 hexamer dimerization.

The origin recognition complex (ORC) of Saccharomyces cerevisiae binds origin DNA and cooperates with Cdc6 and Cdt1 to load the replicative helicase MCM2-7 onto DNA. Helicase loading involves two MCM2-7 hexamers that assemble into a double hexamer around double-stranded DNA. This reaction requires ORC and Cdc6 ATPase activity, but it is unknown how these proteins control MCM2-7 double hexamer formation. We demonstrate that mutations in Cdc6 sensor-2 and Walker A motifs, which are predicted to affect ATP binding, influence the ORC-Cdc6 interaction and MCM2-7 recruitment. In contrast, a Cdc6 sensor-1 mutant affects MCM2-7 loading and Cdt1 release, similar as a Cdc6 Walker B ATPase mutant. Moreover, we show that Orc1 ATP hydrolysis is not involved in helicase loading or in releasing ORC from loaded MCM2-7. To determine whether Cdc6 regulates MCM2-7 double hexamer formation, we analysed complex assembly. We discovered that inhibition of Cdc6 ATPase restricts MCM2-7 association with origin DNA to a single hexamer, while active Cdc6 ATPase promotes recruitment of two MCM2-7 hexamer to origin DNA. Our findings illustrate how conserved Cdc6 AAA+ motifs modulate MCM2-7 recruitment, show that ATPase activity is required for MCM2-7 hexamer dimerization and demonstrate that MCM2-7 hexamers are recruited to origins in a consecutive process.

Involvement of the global Crp regulator in cyclic AMP-dependent utilization of aromatic amino acids by Pseudomonas putida.

The phhAB operon encodes a phenylalanine hydroxylase involved in the conversion of L-phenylalanine into L-tyrosine in Pseudomonas putida. The phhAB promoter is transcribed by RNA polymerase sigma-70 and is unusual in that the specific regulator PhhR acts as an enhancer protein that binds to two distant upstream sites (-75 to -92 and -132 to -149). There is an integration host factor (IHF) binding site that overlaps the proximal PhhR box, and, consequently, IHF acts as an inhibitor of transcription. Use of L-phenylalanine is compromised in a crp-deficient background due to reduced expression from the phhAB promoter. Electrophoretic mobility shift assays and DNase I footprinting assays reveal that Crp binds at a site centered at -109 only in the presence of cyclic AMP (cAMP). We show, using circular permutation analysis, that the simultaneous binding of Crp/cAMP and PhhR bends DNA to bring positive regulators and RNA polymerase into close proximity. This nucleoprotein complex promotes transcription from phhA only in response to L-phenylalanine.

Identification of conditionally essential genes for growth of Pseudomonas putida KT2440 on minimal medium through the screening of a genome-wide mutant library.

In silico models for Pseudomonas putida KT2440 metabolism predict 68 genes to be essential for growth on minimal medium. In this study a genome-wide collection of single-gene P. putida KT2440 knockouts was generated by mini-Tn5 transposon mutagenesis and used to identify genes essential for growth in minimal medium with glucose. Our screening of the knockout library allowed us to rescue mutants for 48 different knockouts that were conditionally essential for growth on minimal medium. The in vivo screening showed that 24 of these mutants had a insertion in genes proposed to be conditionally essential based on in silico models, whereas another 24 newly implicated conditionally essential genes have been found. For 10 of the in silico proposed conditionally essential genes not found in the screening, knockout mutants were available at the Pseudomonas Reference Culture Collection. These mutants were tested for conditional growth on minimal medium, but none of them was shown to be essential, suggesting that the in silico proposal was inaccurate. Among the set of identified conditionally essential genes were a number of genes involved in the biosynthesis of certain amino acids and vitamins. Auxotrophs for all amino acids predicted by the in silico models were found and, in addition, we also found auxotrophs for proline, serine, threonine and methionine, as well as auxotrophs for biotin, nicotinate and vitamin B12 that were not predicted in silico. Metabolic tests were performed to validate the mutants' phenotypes. Auxotrophies for l-Arg, l-Leu, l-Pro and l-Cys were bypassed by external addition of the corresponding d-amino acids, suggesting the existence of number of d- to l-amino acid racemases encoded by the KT2440 genome. Therefore, the in vivo high-throughput analysis presented here provides relevant insights into the metabolic cross-road of biosynthetic pathways in this microorganism, as well as valuable information for the fine tuning of current in silico metabolic models.

Identification and characterization of the PhhR regulon in Pseudomonas putida.

Pseudomonas putida is a soil microorganism that utilizes aromatic amino acids present in root exudates as a nitrogen source. We have previously shown that the PhhR transcriptional regulator induces phhAB genes encoding a phenylalanine hydroxylase. In this study we show, using microarray assays and promoter fusions, that PhhR is a global regulator responsible for the activation of genes essential for phenylalanine degradation, phenylalanine homeostasis and other genes of unknown function. Recently, it has been shown that phenylalanine catabolism occurs through more than one pathway. One of these possible pathways involves the metabolism of phenylalanine via tyrosine, p-hydroxyphenylpyruvate, and homogentisate. We identified two genes within this pathway that encode an acyl-CoA transferase involved in the metabolism of acetoacetate. All genes in this pathway were induced in response to phenylalanine in a PhhR-proficient background. The second potential degradative pathway involves the degradation of phenylalanine to produce phenylpyruvate, which seems to be degraded via phenylacetyl-CoA. A number of mutants in the paa genes encoding phenylacetyl-CoA degradation enzymes fail to grow on phenylpyruvate or phenylacetate, further supporting the existence of this second pathway. We found that the PhhR regulon also includes genes involved in the biosynthesis of aromatic amino acids that are repressed in the presence of phenylalanine, suggesting the possibility of feedback at the transcriptional level. In addition, we found that PhhR modulates the level of expression of the broad-substrate-specificity MexEF/OprN efflux pump. Expression from this pump is under the control of mexT gene product because phenylalanine-dependent transcription from the mexE promoter does not occur in a mexT mutant background. These results place PhhR as an important regulator in the control of bacterial responses to aromatic amino acids.

PhhR binds to target sequences at different distances with respect to RNA polymerase in order to activate transcription.

The NtrC-family PhhR protein of Pseudomonas putida is involved in the control of the metabolism of aromatic amino acids, and it is a dual regulatory protein. When PhhR acts as an activator, it stimulates transcription from its cognate promoters with RNA polymerase/sigma(70) rather than with sigma(54), as is the case for most members of the family. The target binding sites in repressed and activated promoters are defined by the 5'-TGTAAAN(6)TTTACA-3' consensus sequence. PhhR binds to target sites as a dimer with affinity in the range of 0.03 to 6.6 microM, as shown by isothermal titration calorimetry. PhhR activates transcription from both the PP2827 and PP2078 promoters regardless of the absence or presence of aromatic amino acids, whereas PhhR stimulates transcription from certain positively regulated promoters (P(phhA), P(PP3122), P(PP3434), and P(hmg)) only in the presence of phenylalanine and tyrosine or their corresponding keto acids (i.e., phenylpyruvate and p-hydroxyphenylpyruvate). A surprising feature of PhhR-mediated transcriptional activation is that PhhR may bind to one or two upstream target sequences that are located at different distances from the RNA polymerase binding site. This allows PhhR to function as a class I regulator (target sites at -66/-83), a class II regulator (target sites around -40), as well as an enhancer protein (target sites >-128). When functioning as an enhancer protein, PhhR-mediated transcription is modulated by the integration host factor protein. PhhR represses transcription from its own promoter and the promoter of the paaY gene by steric hindrance.

Functional analysis of aromatic biosynthetic pathways in Pseudomonas putida KT2440.

Pseudomonas putida KT2440 is a non-pathogenic prototrophic bacterium with high potential for biotechnological applications. Despite all that is known about this strain, the biosynthesis of essential chemicals has not been fully analysed and auxotroph mutants are scarce. We carried out massive mini-Tn5 random mutagenesis and screened for auxotrophs that require aromatic amino acids. The biosynthesis of aromatic amino acids was analysed in detail including physical and transcriptional organization of genes, complementation assays and feeding experiments to establish pathway intermediates. There is a single pathway from chorismate leading to the biosynthesis of tryptophan, whereas the biosynthesis of phenylalanine and tyrosine is achieved through multiple convergent pathways. Genes for tryptophan biosynthesis are grouped in unlinked regions with the trpBA and trpGDE genes organized as operons and the trpI, trpE and trpF genes organized as single transcriptional units. The pheA and tyrA gene-encoding multifunctional enzymes for phenylalanine and tyrosine biosynthesis are linked in the chromosome and form an operon with the serC gene involved in serine biosynthesis. The last step in the biosynthesis of these two amino acids requires an amino transferase activity for which multiple tyrB-like genes are present in the host chromosome.

Catabolism of phenylalanine by Pseudomonas putida: the NtrC-family PhhR regulator binds to two sites upstream from the phhA gene and stimulates transcription with sigma70.

Pseudomonas putida uses L-phenylalanine as the sole nitrogen source for growth by converting L-phenylalanine to L-tyrosine, which acts as a donor of the amino group. This metabolic step requires the products of the phhA and phhB genes, which form an operon. Expression of the phhA promoter is mediated by the phhR gene product in the presence of L-phenylalanine or L-tyrosine. The PhhR protein belongs to the NtrC family of enhancers. In contrast with most members of this family of regulators, transcription from the promoter of the phhAB operon (P(phhA)) is mediated by RNA polymerase with sigma(70) rather than with sigma(54). The PhhR regulator binds two similar but non-identical upstream PhhR motifs (5'-TGTAAAATTATCGTTACG-3' and 5'-ACAAAAACTGTGTTTCCG-3') that are located 39 and 97 nucleotides upstream of the proposed -35 hexamer for RNA polymerase, respectively. These motifs are called PhhR proximal and PhhR distal binding motifs because of their position with respect to the RNA polymerase binding site. Affinity of PhhR for its target sequences was determined by isothermal titration calorimetry and was found to be around 30 nM for the proximal site and 2 microM for the distal site, and the binding stoichiometry is of a dimer per binding site. Both target sequences are sine qua non requirements for transcription, since inactivation of either of them resulted in no transcription from the phhA promoter. An IHF binding site overlaps the proximal PhhR proximal motif, which is recognized by IHF with a K(D) of around 1.2 microM. IHF may consequently compete with PhhR for binding and indeed inhibits PhhR-dependent phhAB operon expression.