Discovery of Resistance-Reversing Agents in Antibiotic Resistant Strains of Escherichia coli and Klebsiella pneumoniae from Natural Product Libraries

Objective: The objective of this exploratory research is to discover compounds, particularly from natural products, that inhibit ESBL, KPC, and NDM-1 mechanisms of antibiotic resistance in the Gram negative bacteria Escherichia coli and Klebsiella pneumoniae. Methods: This objective will be accomplished utilizing a high-volume bioassay testing natural product samples from the National Center for Natural Products Research. This assay tests samples against 6 different strains of bacteria known to express β-lactamases in the presence and absence of sub-inhibitory concentrations of the test antibiotic. By structuring the assay in this way, differentiation may be made between the inherent antibacterial activity of samples and the synergistic effects between the sample and the antibiotic. Optical density (OD) readings will be used to determine bacterial growth or the lack thereof. Samples showing pronounced activity only in the presence of the antibiotics will be considered active and will be tested in a checkerboard assay to confirm activity. Results: Of over 5,000 samples tested, 35 samples showed synergistic activity, giving a hit rate of 0.7%. Of these 35, the most promising three hits were tested in follow-up checkerboard assays. These three samples all demonstrated synergistic effects with fractional inhibitory concentrations (FIC) of <0.5. Of the samples tested in the checkerboard assays, one was a plant extract, one was a pure compound, and one was a fungal soil isolate obtained from the National Cancer Institute. Conclusions: This study showed the benefits of using a high-volume screen to test samples against resistant bacterial strains. Continued research in this field could prove to be beneficial to the discovery of new drugs for clinically relevant therapeutic applications

Exploiting immunological metaphors in the development of serial, parallel and distributed learning algorithms

This thesis examines the use of immunological metaphors in building serial, parallel, and distributed learning algorithms. It offers a basic study in the development of biologically-inspired algorithms which merge inspiration from biology with known, standard computing technology to examine robust methods of computing. This thesis begins by detailing key interactions found within the immune system that provide inspiration for the development of a learning system. It then exploits the use of more processing power for the development of faster algorithms. This leads to the exploration of distributed computing resources for the examination of more biologically plausible systems. This thesis offers the following main contributions. The components of the immune system that exhibit the capacity for learning are detailed. A framework for discussing learning algorithms is proposed. Three properties of every learning algorithm-memory, adaptation, and decision-making-are identified for this framework, and traditional learning algorithms are placed in the context of this framework. An investigation into the use of immunological components for learning is provided. This leads to an understanding of these components in terms of the learning framework. A simplification of the Artificial Immune Recognition System (AIRS) immune-inspired learning algorithm is provided by employing affinity-dependent somatic hypermutation. A parallel version of the Clonal Selection Algorithm (CLONALG) immune learning algorithm is developed. It is shown that basic parallel computing techniques can provide computational benefits for this algorithm. Exploring this technology further, a parallel version of AIRS is offered. It is shown that applying these same parallel computing techniques to AIRS, while less scalable than when applied to CLONALG, still provides computational gains. A distributed approach to AIRS is offered, and it is argued that this approach provides a more biologically appealing model. The simple distributed approach is proposed in terms of an initial step toward a more complex, distributed system. Biological immune systems exhibit complex cellular interactions. The mechanisms of these interactions, while often poorly understood, hint at an extremely powerful information processing/problem solving system. This thesis demonstrates how the use of immunological principles coupled with standard computing technology can lead to the development of robust, biologically inspired learning algorithms

The validity and reliability characteristics of the M-BACK Questionnaire to assess the barriers, attitudes, confidence, and knowledge of mental health staff regarding metabolic health of mental health service users

Background: Addressing the burden of poor physical health and the subsequent gap in life expectancy experienced by people with mental illness is a major priority in mental health services. To equip mental health staff with the competence to deliver evidence-based interventions, targeted staff training regarding metabolic health is required. In order to evaluate the effectiveness of staff training regarding metabolic health, we aimed to develop a succinct measure to determine the barriers, attitudes, confidence, and knowledge of health practitioners through the development and test–retest reliability of the Metabolic-Barriers, Attitudes, Confidence, and Knowledge Questionnaire (M-BACK). Methods: The M-BACK questionnaire was developed to evaluate the impact of special-ized training in metabolic health care for mental health nurses. Content of the M-BACK was developed from a literature review and refined by an expert review panel and validated via a piloting process. To determine the test–retest reliability of the M-BACK, 31 nursing students recruited from the University of Notre Dame, Sydney completed the questionnaire on two separate occasions, 7 days apart. Intraclass correlation coefficients (ICCs) were calculated for the total score, as well as each of the four domains. Results: Pilot testing was undertaken with a sample of 106 mental health nurses with a mean age 48.2, ranging from 24 to 63 years of age, who participated in six training courses. Questionnaire development resulted in a 16-item instrument, with each item is scored on a five-point Likert scale ranging from “strongly disagree” to “strongly agree.” Test–retest reliability of the M-BACK was completed by 30 of 31 nursing students recruited, ICCs ranged from 0.62 to 0.96. Conclusion: The M-BACK is a reliable measure of the key elements of practitioner perceptions of barriers, and their knowledge, attitudes, and confidence regarding metabolic monitoring in people with mental illness. It can be used to assess the effectiveness of interventions aimed at increasing uptake of metabolic monitoring, a key component of programs to reduce the life expectancy gap in people living with severe mental illness

Carbohydrate Conformation and Lipid Condensation in Monolayers Containing Glycosphingolipid Gb3: Influence of Acyl Chain Structure

AbstractGlobotriaosylceramide (Gb3), a glycosphingolipid found in the plasma membrane of animal cells, is the endocytic receptor of the bacterial Shiga toxin. Using x-ray reflectivity (XR) and grazing incidence x-ray diffraction (GIXD), lipid monolayers containing Gb3 were investigated at the air-water interface. XR probed Gb3 carbohydrate conformation normal to the interface, whereas GIXD precisely characterized Gb3’s influence on acyl chain in-plane packing and area per molecule (APM). Two phospholipids, 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE), were used to study Gb3 packing in different lipid environments. Furthermore, the impact on monolayer structure of a naturally extracted Gb3 mixture was compared to synthetic Gb3 species with uniquely defined acyl chain structures. XR results showed that lipid environment and Gb3 acyl chain structure impact carbohydrate conformation with greater solvent accessibility observed for smaller phospholipid headgroups and long Gb3 acyl chains. In general, GIXD showed that Gb3 condensed phospholipid packing resulting in smaller APM than predicted by ideal mixing. Gb3’s capacity to condense APM was larger for DSPC monolayers and exhibited different dependencies on acyl chain structure depending on the lipid environment. The interplay between Gb3-induced changes in lipid packing and the lipid environment’s impact on carbohydrate conformation has broad implications for glycosphingolipid macromolecule recognition and ligand binding

y-QUIT: Smoking Prevalence, Engagement, and Effectiveness of an Individualized Smoking Cessation Intervention in Youth With Severe Mental Illness

Introduction: Young people with psychosis are six times more likely to be tobacco smokers than their gender- and age-matched peers. Smoking is a major contributor to the 15-year reduced life expectancy among people experiencing severe mental illness (SMI). There is a lack of evidence-supported interventions for smoking cessation among young people with SMI.Material and Methods: The study comprised two phases and aimed to assess (i) the prevalence of smoking among a community sample of young people with psychotic illness or at high risk of developing psychosis; (ii) the proportion who engaged in the intervention; (iii) the proportion who achieved smoking cessation; and (iv) secondary smoking-related outcomes. In phase one, prevalence of smoking was assessed among young people with psychotic illness or at high risk of developing psychosis attending a community-based youth mental health service between 16/5/2017 and 16/11/2017. In phase two, over a 1-year period, individuals identified as smokers were invited to participate in a 12-week tailored smoking cessation intervention program that included pharmacological treatment, motivational interviewing, and behavioral change techniques. Those unwilling to participate in a full intervention were offered a brief intervention. Participants of the full intervention were assessed at baseline and at week 12 endpoint on: daily cigarettes smoked (self-report), exhaled CO, nicotine dependence, readiness to quit, and confidence to quit.Results: In phase one, smoking prevalence was 48.2% (53 of 110) among clients of the youth mental health service. Smokers were significantly more likely to be male (X2 = 6.41 p = 0.009). During phase two, 41 of 61 eligible clients engaged in a smoking cessation intervention (67.2%). Effectiveness: twenty-one clients participated in a full intervention (34.4%), of whom three (14.3%) received a brief intervention initially and during engagement converted to full intervention. Twenty participants (32.8%) received a brief intervention only. Ten participants in the full intervention (47.6%) and five in the brief intervention (25%) dropped out. Six (28.6% of full intervention) reported smoking cessation verified by CO monitoring. Participants who completed the full intervention (n = 9) reduced number of cigarettes smoked, nicotine dependence, and exhaled CO, while readiness to quit and confidence to quit increased. Pharmacotherapy was predominantly combination NRT (n = 18; 85.7%), varenicline (4.8%), oral NRT only (4.8%), or none (4.8%). No adverse events were reported.Conclusion: This pilot real-world study demonstrates that both screening for smoking and offering an effective smoking cessation intervention are achievable in youth experiencing or at risk of psychosis

Hachimoji DNA and RNA: A genetic system with eight building blocks

Reported here are DNA and RNA-like systems built from eight (hachi-) nucleotide letters (-moji) that form four orthogonal pairs. This synthetic genetic biopolymer meets the structural requirements needed to support Darwinism, including a polyelectrolyte backbone, predictable thermodynamic stability, and stereoregular building blocks that fit a Schrödinger aperiodic crystal. Measured thermodynamic parameters predict the stability of hachimoji duplexes, allowing hachimoji DNA to double the information density of natural terran DNA. Three crystal structures show that the synthetic building blocks do not perturb the aperiodic crystal seen in the DNA double helix. Hachimoji DNA was then transcribed to give hachimoji RNA in the form of a functioning fluorescent hachimoji aptamer. These results expand the scope of molecular structures that might support life, including life throughout the cosmos

Climate Risk and Early Warning Systems (CREWS) for Papua New Guinea

Developing and least developed countries are particularly vulnerable to the impact of climate change and climate extremes, including drought. In Papua New Guinea (PNG), severe drought caused by the strong El Niño in 2015–2016 affected about 40% of the population, with almost half a million people impacted by food shortages. Recognizing the urgency of enhancing early warning systems to assist vulnerable countries with climate change adaptation, the Climate Risk and Early Warning Systems (CREWS) international initiative has been established. In this chapter, the CREWS-PNG project is described. The CREWS-PNG project aims to develop an improved drought monitoring and early warning system, running operationally through a collaboration between PNG National Weather Services (NWS), the Australian Bureau of Meteorology and the World Meteorological Organization that will enable better strategic decision-making for agriculture, water management, health and other climate-sensitive sectors. It is shown that current dynamical climate models can provide skillful predictions of regional rainfall at least 3 months in advance. Dynamical climate model-based forecast products are disseminated through a range of Web-based information tools. It is demonstrated that seasonal climate prediction is an effective solution to assist governments and local communities with informed decision-making in adaptation to climate variability and change

Barriers, attitudes, confidence, and knowledge of nurses regarding metabolic health screening and intervention in people with mental illness: a pilot study from Uganda

Background: People with mental illness are at an increased risk for developing cardio-metabolic disorders. Routine screening following pharmacotherapy is however unacceptably low in sub-Saharan African countries with less than 1% adequately screened. It is unknown whether this is due to a lack of adequate competences. Objectives: The aim of this pilot study was to assess the barriers, attitudes, confidence, and knowledge of nurses regarding metabolic health, prevention and treatment in Uganda. Methods: Twenty-eight nurses (39% female, 30.9\ub16.9 years) completed the Metabolic \u2013 Barriers, Confidence, Attitudes and Knowledge Questionnaire and the physical activity prescription rate item of the Exercise in Mental Illness Questionnaire. Results: More than 75% had a positive attitude towards metabolic screening and intervention and more than 50% were confident in providing smoking cessation advice, and physical activity and nutritional counseling. However, 57% stated that their heavy workload prevented them from doing health screening and promotion activities. There was a negative correlation (\u3c1=-0.54, P=0.003) between the frequency of physical activity prescription and the perception of the inability of patients to change. Conclusion: The present findings suggest that nurses are generally supportive of metabolic health screening and intervention but their high workload prevents them from implementing metabolic health interventions

The molecular phenotype of human cardiac myosin associated with hypertrophic obstructive cardiomyopathy

AIM: The aim of the study was to compare the functional and structural properties of the motor protein, myosin, and isolated myocyte contractility in heart muscle excised from hypertrophic cardiomyopathy patients by surgical myectomy with explanted failing heart and non-failing donor heart muscle. METHODS: Myosin was isolated and studied using an in vitro motility assay. The distribution of myosin light chain-1 isoforms was measured by two-dimensional electrophoresis. Myosin light chain-2 phosphorylation was measured by sodium dodecyl sulphate-polyacrylamide gel electrophoresis using Pro-Q Diamond phosphoprotein stain. RESULTS: The fraction of actin filaments moving when powered by myectomy myosin was 21% less than with donor myosin (P = 0.006), whereas the sliding speed was not different (0.310 +/- 0.034 for myectomy myosin vs. 0.305 +/- 0.019 microm/s for donor myosin in six paired experiments). Failing heart myosin showed 18% reduced motility. One myectomy myosin sample produced a consistently higher sliding speed than donor heart myosin and was identified with a disease-causing heavy chain mutation (V606M). In myectomy myosin, the level of atrial light chain-1 relative to ventricular light chain-1 was 20 +/- 5% compared with 11 +/- 5% in donor heart myosin and the level of myosin light chain-2 phosphorylation was decreased by 30-45%. Isolated cardiomyocytes showed reduced contraction amplitude (1.61 +/- 0.25 vs. 3.58 +/- 0.40%) and reduced relaxation rates compared with donor myocytes (TT(50%) = 0.32 +/- 0.09 vs. 0.17 +/- 0.02 s). CONCLUSION: Contractility in myectomy samples resembles the hypocontractile phenotype found in end-stage failing heart muscle irrespective of the primary stimulus, and this phenotype is not a direct effect of the hypertrophy-inducing mutation. The presence of a myosin heavy chain mutation causing hypertrophic cardiomyopathy can be predicted from a simple functional assay