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Citrus greening, also known as Huanglongbing (HLB), is a devastating citrus plant disease caused predominantly by Liberibacter asiaticus. While nearly all Liberibacter species remain uncultured, here we used the culturable L. crescens BT-1 as a model to examine physiological changes in response to the variable osmotic conditions and nutrient availability encountered within the citrus host. Similarly, physiological responses to changes in growth temperature and dimethyl sulfoxide concentrations were also examined, due to their use in many of the currently employed therapies to control the spread of HLB. Sublethal heat stress was found to induce the expression of genes related to tryptophan biosynthesis, while repressing the expression of ribosomal proteins. Osmotic stress induces expression of transcriptional regulators involved in expression of extracellular structures, while repressing the biosynthesis of fatty acids and aromatic amino acids. The effects of osmotic stress were further evaluated by quantifying biofilm formation of L. crescens in presence of increasing sucrose concentrations at different stages of biofilm formation, where sucrose-induced osmotic stress delayed initial cell attachment while enhancing long-term biofilm viability. Our findings revealed that exposure to osmotic stress is a significant contributing factor to the long term survival of L. crescens and, possibly, to the pathogenicity of other Liberibacter species., (© 2022. The Author(s).)

Background: Characteristics of the neighborhood built environment are associated with physical activity (PA). However, few studies with representative samples have examined environmental correlates of domain-specific PA in Latin America. We examined the associations of the perceived neighborhood built environment with domain-specific PA in a large sample of adults from eight Latin American countries., Methods: This study examined data from 8185 adults (aged 18-65 years) from eight Latin American countries. The Neighbourhood Environment Walkability Survey - Abbreviated (NEWS-A) scale was used to assess perceptions of land use mix-diversity, land use mix-access, street connectivity, walking/cycling facilities, aesthetics, safety from traffic, and safety from crime. Perceived proximity from home to public open spaces (metropolitan parks, playgrounds, public squares) and to shopping centers was also measured. Transport-related and leisure-time PA were assessed using the long form of the International Physical Activity Questionnaire. Both logistic and linear regression models were estimated on pooled data., Results: Perceptions of higher land use mix-access (OR: 1.40; 95% CI: 1.22,1.61), the existence of many alternative routes in the neighbourhood (1.12; 1.04,1.20), slow speed of traffic (1.19; 1.03,1.35) and few drivers exceeding the speed limits (1.09; 1.03,1.15) were associated with greater odds of reporting at least 10 min/week of transport-related PA. Perceptions of higher levels of land use mix-diversity, better aesthetics and greater safety from crime, the presence of crosswalks and pedestrian signals, and greater proximity of shopping centers were associated with more min/week of transport-related PA. Perceptions of higher land use mix-diversity (1.12; 1.05,1.20), higher land use mix-access (1.27; 1.13,1.43), more walking/cycling facilities (1.18; 1.09,1.28), and better aesthetics (1.10; 1.02,1.18) were associated with greater odds of engaging in at least 10 min/week of leisure-time PA versus none. Perceptions of higher land use mix-diversity were associated with more min/week of leisure PA., Conclusions: Different perceived neighborhood built environment characteristics were associated with domain-specific PA among adults from Latin America countries. Interventions designed to modify perceptions of the neighbourhood built environment might influence initiation or maintenance of domain-specific PA., Trial Registration: ClinicalTrials. Gov NCT02226627 . Retrospectively registered on August 27, 2014.

Background: Young offenders are known to be a population with high prevalence of mental health disorders. In most cases, these disorders are neither identified nor treated properly, with the majority of them being chronic and difficult to treat. In many countries, the prevalence rates of psychopathology in male young offenders are still unknown and no psychotherapeutic interventions are delivered. Therefore, the main goal of the present study was to assess mental health problems in Portuguese male young offenders placed in either custodial or community-based programs and discuss treatment implications within the juvenile justice interventions., Methods: Participants in this study included 217 male young offenders aged between 14 and 20 years old that were randomly selected using a random number table. From the total sample, 122 (56.3 %) participants were placed in juvenile detention facilities, and 95 (43.7 %) were receiving community-based programs. Participants were interviewed with the Mini-International Neuropsychiatric Interview for Children and Adolescents, a structured interview that assesses DSM-IV Axis I Mental Disorders. Participants aged 18 years or older were also assessed with the antisocial personality disorder section from the Structured Clinical Interview for DSM-IV Axis II Personality Disorders., Results: Results showed a high prevalence of mental health disorders, with a global prevalence of 91.2 % in the total sample. In both groups, global prevalence rates were equally high (93.4 % in youth in custodial versus 88.4 % in youth in community-based programs). Substance-related disorders were more prevalent in youth placed in juvenile facilities, whereas anxiety and mood disorders were more often found in the community-based group. Moreover, oppositional defiant disorder was more prevalent in youth from the community, whereas antisocial personality disorder and conduct disorder were less prevalent than expected in this same group. A high comorbidity rate was also found, with the majority of participants from both groups' fulfilling criteria for two or more disorders. Additionally, participants with conduct disorder were over four times more likely to fulfill criteria for substance abuse., Conclusions: Our findings inform about specific needs concerning mental health intervention that should be taken into account when deciding and planning rehabilitation programs for male young offenders, either from custodial or community-based programs.