Intrinsically disordered regions regulate RhlE RNA helicase functions in bacteria.

RNA helicases-central enzymes in RNA metabolism-often feature intrinsically disordered regions (IDRs) that enable phase separation and complex molecular interactions. In the bacterial pathogen Pseudomonas aeruginosa, the non-redundant RhlE1 and RhlE2 RNA helicases share a conserved REC catalytic core but differ in C-terminal IDRs. Here, we show how the IDR diversity defines RhlE RNA helicase specificity of function. Both IDRs facilitate RNA binding and phase separation, localizing proteins in cytoplasmic clusters. However, RhlE2 IDR is more efficient in enhancing REC core RNA unwinding, exhibits a greater tendency for phase separation, and interacts with the RNase E endonuclease, a crucial player in mRNA degradation. Swapping IDRs results in chimeric proteins that are biochemically active but functionally distinct as compared to their native counterparts. The RECRhlE1-IDRRhlE2 chimera improves cold growth of a rhlE1 mutant, gains interaction with RNase E and affects a subset of both RhlE1 and RhlE2 RNA targets. The RECRhlE2-IDRRhlE1 chimera instead hampers bacterial growth at low temperatures in the absence of RhlE1, with its detrimental effect linked to aberrant RNA droplets. By showing that IDRs modulate both protein core activities and subcellular localization, our study defines the impact of IDR diversity on the functional differentiation of RNA helicases.

Identification and characterisation of G-quadruplex DNA-forming sequences in the Pseudomonas aeruginosa genome.

A number of Gram-negative bacteria such as Pseudomonas aeruginosa are becoming resistant to front-line antibiotics. Consequently, there is a pressing need to find alternative bio-molecular targets for the development of new drugs. Since non-canonical DNA structures such as guanine-quadruplexes (G4s) have been implicated in regulating transcription, we were interested in determining whether there are putative quadruplex-forming sequences (PQS) in the genome of Pseudomonas aeruginosa. Using bioinformatic tools, we screened 36 genes potentially relevant to drug resistance for the presence of PQS and 10 of these were selected for biophysical characterisation (i.e. circular dichroism and thermal difference UV/Vis spectroscopy). These studies showed that three of these G-rich sequences (linked to murE, ftsB and mexC genes) form stable guanine-quadruplexes which were studied by NMR spectroscopy; detailed analysis of one of the sequences (mexC) confirmed that it adopts a two-quartet antiparallel quadruplex structure in the presence of K+ ions. We also show by FRET melting assays that small molecules can stabilise these three new G4 DNA structures under physiological conditions. These initial results could be of future interest in the development of new antibiotics with alternative bio-molecular targets which in turn would help tackle antimicrobial resistance.

A Zur-mediated transcriptional regulation of the zinc export system in Pseudomonas aeruginosa.

The control of cellular zinc (Zn) concentrations by dedicated import and export systems is essential for the survival and virulence of Pseudomonas aeruginosa. The transcription of its many Zn transporters is therefore tightly regulated by a known set of transcription factors involved in either the import or the export of Zn. In this work, we show that the Zur protein, a well-known repressor of Zn import, plays a dual role and functions in both import and export processes. In a situation of Zn excess, Zur represses Zn entry, but also activates the transcription of czcR, a positive regulator of the Zn export system. To achieve this, Zur binds at two sites, located by DNA footprinting in the region downstream the czcR transcription start site. In agreement with this regulation, a delay in induction of the efflux system is observed in the absence of Zur and Zn resistance is reduced. The discovery of this regulation highlights a new role of Zur as global regulator of Zn homeostasis in P. aeruginosa disclosing an important link between Zur and zinc export.

KaiC-like proteins contribute to stress resistance and biofilm formation in environmental Pseudomonas species.

KaiC is the central cog of the circadian clock in Cyanobacteria. Close homologues of this protein are widespread among nonphotosynthetic bacteria, but the function, interaction network, and mechanism of action of these proteins are still largely unknown. Here, we focus on KaiC homologues found in environmental Pseudomonas species. Using bioinformatics, we describe the distribution of this protein family in the genus and reveal a conserved interaction network comprising a histidine kinase and response regulator. We characterize experimentally the only KaiC homologue present in Pseudomonas putida KT2440 and Pseudomonas protegens CHA0. Through phenotypic assays and transcriptomics, we show that KaiC is involved in osmotic and oxidative stress resistance in P. putida and in biofilm production in both species. KaiC homologues are found in different phosphorylation states and physically interact with a cognate histidine kinase and response regulator. In contrast with cyanobacterial counterparts, the expression and phosphorylation of KaiC homologues do not correlate with light variations under 12:12 light: dark cycles in either Pseudomonas species, and KaiC itself is not required to support a light-driven behaviour in P. putida. Overall, this suggests that KaiC homologues in Pseudomonas species are involved in environmental stress resistance but not in responses to diurnal rhythms.

Role of Two-Component System Networks in Pseudomonas aeruginosa Pathogenesis.

Two-component systems (TCS) are the largest family of signaling systems in the bacterial kingdom. They enable bacteria to cope with a wide range of environmental conditions via the sensing of stimuli and the transduction of the signal into an appropriate cellular adaptation response. Pseudomonas aeruginosa possesses one of the richest arrays of TCSs in bacteria and they have been the subject of intense investigation for more than 20 years. Most of the P. aeruginosa TCSs characterized to date affect its pathogenesis, via the regulation of virulence factors expression, modulation of the synthesis of antibiotic/antimicrobial resistance mechanisms, and/or via linking virulence to energy metabolism. Here, we give an overview of the current knowledge on P. aeruginosa TCSs, citing key examples for each of the above-mentioned regulatory actions. We then conclude by mentioning few small molecule inhibitors of P. aeruginosa TCSs that have shown an antimicrobial action in vitro.

Mechanism of inhibition of bacterial RNA helicases by diazo dyes and implications for antimicrobial drug development.

RNA helicases represent attractive drug targets as their activity is linked to several human diseases and impacts microbial infectious processes. While some inhibitors of human RNA helicases demonstrated therapeutic potential as anticancer and antiviral drugs in preclinical trials, chemical inhibition of microbial RNA helicases is less investigated. Here, we address this matter by focusing on the RhlE proteobacterial group of RNA helicases. Having previously shown that the RhlE2 RNA helicase is important for the virulence of the opportunistic pathogen Pseudomonas aeruginosa, we screened a library of 1280 molecules for inhibitors of RhlE2 RNA-dependent ATP hydrolytic activity. The most potent inhibitor is the diazo compound Chicago Sky Blue (CSB). Using hydrogen-deuterium exchange mass spectrometry and biochemical assays, we mapped CSB binding to RhlE2 catalytic core and defined its inhibitory mechanism. Targeting microbial RNA helicases as therapeutic strategy is challenging due to potential side-effects linked to protein conservation across life kingdoms. Interestingly, our structure-activity relationship analysis delineates other diazo dyes closely related to CSB differentially affecting RhlE homologs. Our work could thus be exploited for future drug development studies, which are extremely timely considering the increasing spread of antibiotic resistance among bacterial pathogens.

Expert-based medication reviews to reduce polypharmacy in older patients in primary care: a northern-Italian cluster-randomised controlled trial.

BACKGROUND: Evidence regarding clinically relevant effects of interventions aiming at reducing polypharmacy is weak, especially for the primary care setting. This study was initiated with the objective to achieve clinical benefits for older patients (aged 75+) by means of evidence-based reduction of polypharmacy (defined as ≥8 prescribed drugs) and inappropriate prescribing in general practice. METHODS: The cluster-randomised controlled trial involved general practitioners and patients in a northern-Italian region. The intervention consisted of a review of patient's medication regimens by three experts who gave specific recommendations for drug discontinuation. Main outcome measures were non-elective hospital admissions or death within 24 months (composite primary endpoint). Secondary outcomes were drug numbers, hospital admissions, mortality, falls, fractures, quality of life, affective status, cognitive function. RESULTS: Twenty-two GPs/307 patients participated in the intervention group, 21 GPs/272 patients in the control group. One hundred twenty-five patients (40.7%) experienced the primary outcome in the intervention group, 87 patients (32.0%) in the control group. The adjusted rates of occurrence of the primary outcome did not differ significantly between the study groups (intention-to-treat analysis: adjusted odds ratio 1.46, 95%CI 0.99-2.18, p = 0.06; per-protocol analysis: adjusted OR 1.33, 95%CI 0.87-2.04, p = 0.2). Hospitalisations as single endpoint occurred more frequently in the intervention group according to the unadjusted analysis (OR 1.61, 95%CI 1.03-2.51, p = 0.04) but not in the adjusted analysis (OR 1.39, 95%CI 0.95-2.03, p = 0.09). Falls occurred less frequently in the intervention group (adjusted OR 0.55, 95%CI 0.31-0.98; p = 0.04). No significant differences were found regarding the other outcomes. Definitive discontinuation was obtained for 67 (16.0%) of 419 drugs rated as inappropriate. About 6% of the prescribed drugs were PIMs. CONCLUSIONS: No conclusive effects were found regarding mortality and non-elective hospitalisations as composite respectively single endpoints. Falls were significantly reduced in the intervention group, although definitive discontinuation was achieved for only one out of six inappropriate drugs. These results indicate that (1) even a modest reduction of inappropriate medications may entail positive clinical effects, and that (2) focusing on evidence-based new drug prescriptions and prevention of polypharmacy may be more effective than deprescribing. TRIAL REGISTRATION: Current Controlled Trials (ID ISRCTN: 38449870), date: 11/09/2013.

Global Analysis of the Zinc Homeostasis Network in Pseudomonas aeruginosa and Its Gene Expression Dynamics.

Zinc is one of the most important trace elements for life and its deficiency, like its excess, can be fatal. In the bacterial opportunistic pathogen Pseudomonas aeruginosa, Zn homeostasis is not only required for survival, but also for virulence and antibiotic resistance. Thus, the bacterium possesses multiple Zn import/export/storage systems. In this work, we determine the expression dynamics of the entire P. aeruginosa Zn homeostasis network at both transcript and protein levels. Precisely, we followed the switch from a Zn-deficient environment, mimicking the initial immune strategy to counteract bacterial infections, to a Zn-rich environment, representing the phagocyte metal boost used to eliminate an engulfed pathogen. Thanks to the use of the NanoString technology, we timed the global silencing of Zn import systems and the orchestrated induction of Zn export systems. We show that the induction of Zn export systems is hierarchically organized as a function of their impact on Zn homeostasis. Moreover, we identify PA2807 as a novel Zn resistance component in P. aeruginosa and highlight new regulatory links among Zn-homeostasis systems. Altogether, this work unveils a sophisticated and adaptive homeostasis network, which complexity is key in determining a pathogen spread in the environment and during host-colonization.

The DEAD-box RNA helicase RhlE2 is a global regulator of Pseudomonas aeruginosa lifestyle and pathogenesis.

RNA helicases perform essential housekeeping and regulatory functions in all domains of life by binding and unwinding RNA molecules. The bacterial RhlE-like DEAD-box RNA helicases are among the least well studied of these enzymes. They are widespread especially among Proteobacteria, whose genomes often encode multiple homologs. The significance of the expansion and diversification of RhlE-like proteins for bacterial fitness has not yet been established. Here, we study the two RhlE homologs present in the opportunistic pathogen Pseudomonas aeruginosa. We show that, in the course of evolution, RhlE1 and RhlE2 have diverged in their biological functions, molecular partners and RNA-dependent enzymatic activities. Whereas RhlE1 is mainly needed for growth in the cold, RhlE2 also acts as global post-transcriptional regulator, affecting the level of hundreds of cellular transcripts indispensable for both environmental adaptation and virulence. The global impact of RhlE2 is mediated by its unique C-terminal extension, which supports the RNA unwinding activity of the N-terminal domain as well as an RNA-dependent interaction with the RNase E endonuclease and the cellular RNA degradation machinery. Overall, our work reveals how the functional and molecular divergence between two homologous RNA helicases can contribute to bacterial fitness and pathogenesis.

Epidemiology and associated factors of polypharmacy in older patients in primary care: a northern Italian cross-sectional study.

BACKGROUND: A precondition for developing strategies to reduce polypharmacy and its well-known harmful consequences is to study its epidemiology and associated factors. The objective of this study was to analyse the prevalence of polypharmacy (defined as ≥8 prescribed drugs), of potentially inappropriate medications (PIMs) and major drug-drug interactions (DDIs) among community-dwelling general practice patients aged ≥75 years and to identify characteristics being associated with polypharmacy. METHODS: This cross-sectional study is derived from baseline data (patients' demographic/biometric characteristics, diagnoses, medication-related data, cognitive/affective status, quality of life) of a northern-Italian cluster-RCT. PIMs and DDIs were assessed using the 2012 Beers criteria and the Lexi-Interact® database. Data were analysed using descriptive methods, Wilcoxon rank-sum tests, Fisher's exact tests and Spearman correlations. RESULTS: Of the eligible patients aged 75+, 13.4% were on therapy with ≥8 drugs. Forty-three general practitioners and 579 patients participated in the study. Forty five point nine percent of patients were treated with ≥1 Beers-listed drugs. The most frequent PIMs were benzodiazepines/hypnotics (19.7% of patients) and NSAIDs (6.6%). Sixty seven point five percent of patients were exposed to ≥1 major DDI, 35.2% to ≥2 major DDIs. Antithrombotic/anticoagulant medications (30.4%) and antidepressants/antipsychotics (23.1%) were the most frequently interacting drugs. Polypharmacy was significantly associated with a higher number of major DDIs (Spearman's rho 0.33, p < 0.001) and chronic conditions (Spearman's rho 0.20, p < 0.001), higher 5-GDS scores (thus, lower affective status) (Spearman's rho 0.12, p = 0.003) and lower EQ-5D-5L scores (thus, lower quality of life) (Spearman's rho - 0.14, p = 0.001). Patients' age/sex, 6-CIT scores (cognitive status), BMI or PIM use were not correlated with the number of drugs. CONCLUSIONS: The prevalence of polypharmacy, PIMs and major DDIs was considerable. Results indicate that physicians should particularly observe their patients with multiple conditions, reduced health and affective status, independently from other patients' characteristics. Careful attention about indication, benefit and potential risk should be paid especially to patients on therapy with specific drug classes identified as potentially inappropriate or prone to major DDIs in older persons (e.g., benzodiazepines, NSAIDs, protonic pump inhibitors, antithrombotics/anticoagulants, antidepressants/antipsychotics). TRIAL REGISTRATION: The cluster-RCT on which this cross-sectional analysis is based was registered with Current Controlled Trials Ltd. (ID ISRCTN: 38449870 ) on 2013-09-11.

Dual role of a (p)ppGpp- and (p)ppApp-degrading enzyme in biofilm formation and interbacterial antagonism.

The guanosine nucleotide-based second messengers ppGpp and pppGpp (collectively: (p)ppGpp) enable adaptation of microorganisms to environmental changes and stress conditions. In contrast, the closely related adenosine nucleotides (p)ppApp are involved in type VI secretion system (T6SS)-mediated killing during bacterial competition. Long RelA-SpoT Homolog (RSH) enzymes regulate synthesis and degradation of (p)ppGpp (and potentially also (p)ppApp) through their synthetase and hydrolase domains, respectively. Small alarmone hydrolases (SAH) that consist of only a hydrolase domain are found in a variety of bacterial species, including the opportunistic human pathogen Pseudomonas aeruginosa. Here, we present the structure and mechanism of P. aeruginosa SAH showing that the enzyme promiscuously hydrolyses (p)ppGpp and (p)ppApp in a strictly manganese-dependent manner. While being dispensable for P. aeruginosa growth or swimming, swarming, and twitching motilities, its enzymatic activity is required for biofilm formation. Moreover, (p)ppApp-degradation by SAH provides protection against the T6SS (p)ppApp synthetase effector Tas1, suggesting that SAH enzymes can also serve as defense proteins during interbacterial competition.

Happy Birthday: 30 Years of RNA Helicases.

RNA helicases are ubiquitous, highly conserved RNA-binding enzymes that use the energy derived from the hydrolysis of nucleoside triphosphate to modify the structure of RNA molecules and/or the functionality of ribonucleoprotein complexes. Ultimately, the action of RNA helicases results in changes in gene expression that allow the cell to perform crucial functions. In this chapter, we review established and emerging concepts for DEAD-box and DExH-box RNA helicases. We mention examples from both eukaryotic and prokaryotic systems, in order to highlight common themes and specific actions.

The CzcCBA Efflux System Requires the CadA P-Type ATPase for Timely Expression Upon Zinc Excess in Pseudomonas aeruginosa.

Zinc (Zn) is a trace element essential for life but can be toxic if present in excess. While cells have import systems to guarantee a vital Zn intracellular concentration, they also rely on export systems to avoid lethal Zn overload. In particular, the opportunistic pathogen Pseudomonas aeruginosa possesses four Zn export systems: CadA, CzcCBA, CzcD, and YiiP. In this work, we compare the importance for bacterial survival of each export system at high Zn concentrations. We show that the P-type ATPase CadA, and the efflux pump CzcCBA are the main efflux systems affecting the bacterium tolerance to Zn. In addition, cadA and czcCBA genes expression kinetics revealed a hierarchical organization and interdependence. In the presence of high Zn concentrations, cadA expression is very rapidly induced (<1 min), while czcCBA expression occurs subsequently (>15 min). Our present data show that the fast responsiveness of cadA to Zn excess is due to its transcriptional activator, CadR, which is constitutively present on its promoter and promptly activating cadA gene expression upon Zn binding. Moreover, we showed that CadA is essential for a timely induction of the CzcCBA efflux system. Finally, we observed an induction of cadA and czcCBA efflux systems upon phagocytosis of P. aeruginosa by macrophages, in which a toxic metal boost is discharged into the phagolysosome to intoxicate microbes. Importantly, we demonstrated that the regulatory link between induction of the CzcCBA system and the repression of the OprD porin responsible for carbapenem antibiotic resistance, is maintained in the macrophage environment.

[Dimensional treatment of aggression, impulsivity, and activation: a study on psychiatric inpatients]. / Trattamento dimensionale dell'aggressività, impulsività e attivazione: uno studio su pazienti psichiatrici ospedalizzati.

INTRODUCTION: Most psychotropic drugs are effective for several mental disorders, rather than for specific diagnoses. The dimensional approach to psychiatric nosology can explain the non-specificity of drug action, and it could usefully integrate the traditional categorical approach and may help optimize personalised psychiatric treatment. This study aimed at examining the use of antiepileptic drugs, particularly valproate, for the treatment of prominent aggression, impulsivity, and activation, within the conceptual framework of a "dimensional pharmacotherapy" strategy. METHODS: This observational, naturalistic study included 846 adult psychiatric inpatients. Within 48 hours from admission and then again at discharge, each patient was administered the Brief Psychiatric Rating Scale (BPRS) and the SVARAD scale for rapid dimensional assessment. RESULTS: We found a statistically significant association between the prescription of an antiepileptic drug (valproate in the vast majority of cases) and the presence of high levels of aggression, impulsivity, and activation. In patients with high levels of these psychopathological dimensions, the prescription of an antiepileptic drug was significantly associated with a greater decrease in BPRS total score from admission to discharge. This finding remained significant after the exclusion of patients experiencing a manic or mixed episode. CONCLUSIONS: Although methodological limitations dictate caution in interpreting our results, these preliminary findings suggest that a "dimensional pharmacotherapy" strategy (i.e., selecting drugs based on neurobiological action rather than categorical diagnosis) for the treatment of aggression, impulsivity and activation is commonly used in daily practice and may lead to greater clinical improvement, in the absence of severe adverse effects.

Auxiliary domains of the HrpB bacterial DExH-box helicase shape its RNA preferences.

RNA helicases are fundamental players in RNA metabolism: they remodel RNA secondary structures and arrange ribonucleoprotein complexes. While DExH-box RNA helicases function in ribosome biogenesis and splicing in eukaryotes, information is scarce about bacterial homologs. HrpB is the only bacterial DExH-box protein whose structure is solved. Besides the catalytic core, HrpB possesses three accessory domains, conserved in all DExH-box helicases, plus a unique C-terminal extension (CTE). The function of these auxiliary domains remains unknown. Here, we characterize genetically and biochemically Pseudomonas aeruginosa HrpB homolog. We reveal that the auxiliary domains shape HrpB RNA preferences, affecting RNA species recognition and catalytic activity. We show that, among several types of RNAs, the single-stranded poly(A) and the highly structured MS2 RNA strongly stimulate HrpB ATPase activity. In addition, deleting the CTE affects only stimulation by structured RNAs like MS2 and rRNAs, while deletion of accessory domains results in gain of poly(U)-dependent activity. Finally, using hydrogen-deuterium exchange, we dissect the molecular details of HrpB interaction with poly(A) and MS2 RNAs. The catalytic core interacts with both RNAs, triggering a conformational change that reorients HrpB. Regions within the accessory domains and CTE are, instead, specifically responsive to MS2. Altogether, we demonstrate that in bacteria, like in eukaryotes, DExH-box helicase auxiliary domains are indispensable for RNA handling.

Multiple Roles of c-di-GMP Signaling in Bacterial Pathogenesis.

The intracellular signaling molecule cyclic di-GMP (c-di-GMP) regulates the lifestyle of bacteria and controls many key functions and mechanisms. In the case of bacterial pathogens, a wide variety of virulence lifestyle factors have been shown to be regulated by c-di-GMP. Evidence of the importance of this molecule for bacterial pathogenesis has become so great that new antimicrobial agents are tested for their capacity of targeting c-di-GMP signaling. This review summarizes the current knowledge on this topic and reveals its application for the development of new antivirulence intervention strategies.

[Problems and perspectives in psychiatric diagnosis]. / Problemi e prospettive in tema di diagnosi psichiatrica.

Diagnosis in psychiatry is a complex and difficult issue. A great many considerations have been made about the debatable ontological status of mental disorders and the difficulties in providing flawless definitions for them. While these considerations help appreciate the subtleties and difficulties of the topic, they do not imply that mental disorders do not exist or that nosological classification is unnecessary or useless. Although classifications have some inherent flaws and limitations, they can nevertheless be useful. The current psychiatric nosology, however, is based on a categorical approach that has been the object of much criticism. Alternatives include the prototype approach, which has some strong points but also a number of potential disadvantages, and the dimensional approach. The latter approach, though not solving all problems, has recently attracted increasing interest and has received substantial empirical support. There are several ways of conceptualising dimensions and using them in the context of assessment and diagnosis. One of these ways is represented by the SVARAD (Scala per la VAlutazione RApida Dimensionale, i.e., "rapid dimensional assessment scale"), which is an observer-rated scale that covers 10 psychopathological dimensions. Two decades of clinical and research experience have supported its reliability, validity, and ease of use. Dimensional approaches of this kind could easily integrate and enrich the traditional DSM or ICD assessment and may help optimize personalised psychiatric treatment.

Dimensional psychopathology of schizophrenia: SVARAD dimensional profiles in an acute inpatient sample

Objective: This study aimed at describing the dimensional profile of schizophrenia in an acute inpatient sample, and at exploring the different components of psychopathological suffering within this single diagnostic category according to a dimensional perspective. Methods: The sample consisted of 81 schizophrenic patients consecutively admitted to a psychiatric inpatient care unit. Each patient was administered the rapid dimensional assessment scale SVARAD (acronym for the Italian name "Scala per la VAlutazione RApida Dimensionale") and the Global Assessment of Functioning scale. Dimensional profiles were obtained from mean scores on each SVARAD item. Analysis of variance was used to test for differences between groups in mean SVARAD item scores. Results: The findings indicated that age, sex, psychosocial functioning, involuntary nature of the admission, and predominance of positive or disorganisation symptomatology are associated with differences in the mean dimensional profile. Also, sizable subgroups of patients with clinically significant levels of psychopathological dimensions (e.g., Sadness/Demoralisation, Anger/Aggressiveness, Impulsivity) that have limited overlap with the traditionally acknowledged domains of positive symptoms, negative symptoms, and disorganisation, were identified. No differences in any psychopathological dimension were found between the classical schizophrenia subtypes. Conclusions: The dimensional assessment with SVARAD helps appreciate the singularity of each patient within the same diagnostic category. The study suggests that recognising different dimensional profiles with the SVARAD may allow more personalised choices of treatment.

Preliminary findings on the association between attachment patterns and levels of growth hormone in a sample of children with non-organic failure to thrive

Introduction: Deficiency of growth hormone (GH) in absence of pituitary injuries is one of the causes of short stature and of the non organic failure to thrive (NOFTT) condition. Advances in developmental psychology have highlighted the role of emotions and caregiving behaviors in the organization of child's personality and psychobiology, with the mother-son attachment bond being considered a fundamental developmental experience. The objective of the present preliminary study was to assess whether there are significant correlations between attachment patterns and GH levels in a sample of subjects with NOFTT. Methods: Overall, 27 children (mean age 9.49±2.63 years) with NOFTT were enrolled. Perceived attachment security was assessed through the Security Scale (SS) and its subscales focused on maternal and paternal security. Pearson partial correlation was used to test associations between GH levels and SS measures adjusting for confounding factors (i.e. age, gender and body mass index). Results: Across all subjects, GH was significantly positively correlated with general security (r=0.425; p=0.038) and maternal security (r=0.451; p=0.027) and not significantly correlated with paternal security (r=0.237; p=0.264). Discussion: These findings preliminarily suggest that the association between GH levels and perceived attachment security may play a role in the pathophysiology of NOFTT and add to the accumulating evidence that attachment patterns may be related with specific psychoendocrine underpinnings.

Lifestyle transitions and adaptive pathogenesis of Pseudomonas aeruginosa.

Pseudomonas aeruginosa acute and chronic infections are of great concern to human health, especially in hospital settings. It is currently assumed that P. aeruginosa has two antagonistic pathogenic strategies that parallel two different lifestyles; free-living cells are predominantly cytotoxic and induce an acute inflammatory reaction, while biofilm-forming communities cause refractory chronic infections. Recent findings suggest that the planktonic-to-sessile transition is a complex, reversible and overall dynamic differentiation process. Here, we examine how the Gac/Rsm regulatory cascade, a key player in this lifestyle switch, endows P. aeruginosa with both a permissive lifecycle in nature and flexible virulence strategy during infection.