Recognition of Antimicrobial Peptides by a Bacterial Sensor Kinase

SummaryPhoQ is a membrane bound sensor kinase important for the pathogenesis of a number of Gram-negative bacterial species. PhoQ and its cognate response regulator PhoP constitute a signal-transduction cascade that controls inducible resistance to host antimicrobial peptides. We show that enzymatic activity of Salmonella typhimurium PhoQ is directly activated by antimicrobial peptides. A highly acidic surface of the PhoQ sensor domain participates in both divalent-cation and antimicrobial-peptide binding as a first step in signal transduction across the bacterial membrane. Identification of PhoQ signaling mutants, binding studies with the PhoQ sensor domain, and structural analysis of this domain can be incorporated into a model in which antimicrobial peptides displace divalent cations from PhoQ metal binding sites to initiate signal transduction. Our findings reveal a molecular mechanism by which bacteria sense small innate immune molecules to initiate a transcriptional program that promotes bacterial virulence

HIV/AIDS information promotion at the library: creative campaigns for young adults

Background: While rates of new HIV diagnoses have gone down nationally, Florida’s HIV-positive population is growing and remains one of the largest in the country. Given this landscape, it is clear that diverse, creative, and collaborative efforts are needed to better inform the public about HIV risks, prevention, and treatment and to encourage healthy behaviors. Case Presentation: Building on previous work, librarians at the University of Florida engaged in a yearlong project to raise awareness about HIV/AIDS risks, prevention, and treatment among university students and to improve their information-seeking behaviors related to this disease. The “Creative Campaigns” project included 3 distinct elements of activity and engagement, designed to complement one another: a graphic novel contest, a social media campaign, and training for campus health care providers. The contest yielded 4 high-quality submissions, and the monthlong social media campaign garnered over 50,000 views and utilized Facebook ads to extend beyond the library’s typical audience. The instruction proved useful to campus counseling and wellness staff. Conclusions: Overall, the team considered the project a success in terms of reaching new audiences in new ways, and several of its components have been integrated into subsequent projects and regular operations. Exploring new methods of outreach through social media and creative formats required careful planning and the development of new skill sets amongst project team members but proved to be a rewarding way to generate engagement in the local community

Metal ion-dependent, reversible, protein filament formation by designed beta-roll polypeptides

<p>Abstract</p> <p>Background</p> <p>A right-handed, calcium-dependent β-roll structure found in secreted proteases and repeat-in-toxin proteins was used as a template for the design of minimal, soluble, monomeric polypeptides that would fold in the presence of Ca²⁺. Two polypeptides were synthesised to contain two and four metal-binding sites, respectively, and exploit stacked tryptophan pairs to stabilise the fold and report on the conformational state of the polypeptide.</p> <p>Results</p> <p>Initial analysis of the two polypeptides in the presence of calcium suggested the polypeptides were disordered. The addition of lanthanum to these peptides caused aggregation. Upon further study by right angle light scattering and electron microscopy, the aggregates were identified as ordered protein filaments that required lanthanum to polymerize. These filaments could be disassembled by the addition of a chelating agent. A simple head-to-tail model is proposed for filament formation that explains the metal ion-dependency. The model is supported by the capping of one of the polypeptides with biotin, which disrupts filament formation and provides the ability to control the average length of the filaments.</p> <p>Conclusion</p> <p>Metal ion-dependent, reversible protein filament formation is demonstrated for two designed polypeptides. The polypeptides form filaments that are approximately 3 nm in diameter and several hundred nm in length. They are not amyloid-like in nature as demonstrated by their behaviour in the presence of congo red and thioflavin T. A capping strategy allows for the control of filament length and for potential applications including the "decoration" of a protein filament with various functional moieties.</p

In Support of a Patient-Driven Initiative and Petition to Lower the High Price of Cancer Drugs

Comment in Lowering the High Cost of Cancer Drugs--III. [Mayo Clin Proc. 2016] Lowering the High Cost of Cancer Drugs--I. [Mayo Clin Proc. 2016] Lowering the High Cost of Cancer Drugs--IV. [Mayo Clin Proc. 2016] In Reply--Lowering the High Cost of Cancer Drugs. [Mayo Clin Proc. 2016] US oncologists call for government regulation to curb drug price rises. [BMJ. 2015

An Individual Participant Data Meta-analysis: Behavioral Treatments for Children and Adolescents With Attention-Deficit/Hyperactivity Disorder

Objective: Behavioral interventions are well established treatments for children with attention-deficit/hyperactivity disorder (ADHD). However, insight into moderators of treatment outcome is limited.Method: We conducted an individual participant data meta-analysis [IPDMA], including data of randomized controlled behavioral intervention trials for individuals with ADHD[less than]18 years. Outcomes were symptoms of ADHD, oppositional defiant disorder (ODD), and conduct disorder (CD) and impairment. Moderators investigated were symptoms and impairment severity, medication use, age, IQ, sex, socioeconomic status, and single parenthood. Results: For raters most proximal to treatment, small to medium sized effects of behavioral interventions were found for symptoms of ADHD, inattention, hyperactivity/impulsivity (HI), ODD and CD, and impairment. Blinded outcomes were only available for small preschool subsamples and limited measures. CD symptoms and/or diagnosis moderated outcome on ADHD, HI, ODD, and CD symptoms. Single parenthood moderated ODD outcome, ADHD severity moderated impairment outcome. Higher baseline CD or ADHD symptoms, a CD diagnosis, and single parenthood were related to worsening of symptoms in the untreated, but not in the treated group, indicating a protective rather than an ameliorative effect of behavioral interventions for these children.Conclusion: Behavioral treatments are effective for reducing ADHD symptoms, behavioral problems, and impairment as reported by raters most proximal to treatment. Those with severe CD or ADHD symptoms, a CD diagnosis, or single parents, should be prioritized for treatment, as they may evidence worsening of symptoms in the absence of intervention

A comparison of the clinical effectiveness and cost of specialised individually-delivered parent training for preschool attention-deficit/hyperactivity disorder and a generic, group-based programme: a multi-centre, randomised controlled trial of the New Forest Parenting Programme versus Incredible Years

Objective: To compare the efficacy and cost of specialised individually-delivered parent training (PT) for preschool children with attention-deficit/ hyperactivity disorder (ADHD) against generic group-based PT and treatment as usual (TAU). Design: Multi-centre, three-arm parallel group randomised controlled trial. Research Setting: National Health Service Trusts. Participants: Preschool children (33-54 months) fulfilling ADHD research diagnostic criteria. Interventions: New Forest Parenting Programme (NFPP) – 12 week individual, home-delivered ADHD PT programme; Incredible Years (IY) – 12 week group-based, PT programme initially designed for children with behaviour problems. Main outcome measures: Primary outcome - Parent ratings of child’s ADHD symptoms (Swanson, Nolan & Pelham Questionnaire - SNAP-IV). Secondary outcomes - teacher ratings (SNAP-IV) and direct observations of ADHD symptoms and parent/teacher ratings of conduct problems. NFPP, IY and TAU outcomes were measured at baseline (T1) and post-treatment (T2). NFPP and IY outcomes only were measured 6 months post treatment (T3). Researchers, but not therapists or parents, were blind to treatment allocation. Analysis employed mixed effect regression models (multiple imputation). Intervention and other costs were estimated using standardized approaches. Results: NFPP and IY did not differ on parent-rated SNAP-IV, ADHD combined symptoms (mean difference -0.009 95%CI [-0.191, 0.173], p=0.921) or any other measure. Small, non-significant, benefits of NFPP over TAU were seen for parent-rated SNAP-IV, ADHD combined symptoms (-0.189 95%CI [-0.380, 0.003], p=0.053). NFPP significantly reduced parent-rated conduct-problems compared to TAU across scales (p-values.05). The cost per family of providing NFPP in the trial was significantly lower than IY (£1,591 versus £2,103). Conclusions: Although, there were no differences between NFPP and IY with regards clinical effectiveness, individually-delivered NFPP cost less. However, this difference may be reduced when implemented in routine clinical practice. Clinical decisions should take into account parental preferences between delivery approaches. Funding: National Institute of Health Research. Trial Registration: Trial name: COPPI Trial; ISRCTN39288126

Evidence generation and reproducibility in cell and gene therapy research: A call to action.

Editoria

Circulating microRNAs in sera correlate with soluble biomarkers of immune activation but do not predict mortality in ART treated individuals with HIV-1 infection: A case control study

Introduction: The use of anti-retroviral therapy (ART) has dramatically reduced HIV-1 associated morbidity and mortality. However, HIV-1 infected individuals have increased rates of morbidity and mortality compared to the non-HIV-1 infected population and this appears to be related to end-organ diseases collectively referred to as Serious Non-AIDS Events (SNAEs). Circulating miRNAs are reported as promising biomarkers for a number of human disease conditions including those that constitute SNAEs. Our study sought to investigate the potential of selected miRNAs in predicting mortality in HIV-1 infected ART treated individuals. Materials and Methods: A set of miRNAs was chosen based on published associations with human disease conditions that constitute SNAEs. This case: control study compared 126 cases (individuals who died whilst on therapy), and 247 matched controls (individuals who remained alive). Cases and controls were ART treated participants of two pivotal HIV-1 trials. The relative abundance of each miRNA in serum was measured, by RTqPCR. Associations with mortality (all-cause, cardiovascular and malignancy) were assessed by logistic regression analysis. Correlations between miRNAs and CD4+ T cell count, hs-CRP, IL-6 and D-dimer were also assessed. Results: None of the selected miRNAs was associated with all-cause, cardiovascular or malignancy mortality. The levels of three miRNAs (miRs -21, -122 and -200a) correlated with IL-6 while miR-21 also correlated with D-dimer. Additionally, the abundance of miRs -31, -150 and -223, correlated with baseline CD4+ T cell count while the same three miRNAs plus miR- 145 correlated with nadir CD4+ T cell count. Discussion: No associations with mortality were found with any circulating miRNA studied. These results cast doubt onto the effectiveness of circulating miRNA as early predictors of mortality or the major underlying diseases that contribute to mortality in participants treated for HIV-1 infection