Nuclear Magnetic Resonance Chemical Shift as a Probe for Single-Molecule Charge Transport

Existing modelling tools, developed to aid the design of efficient molecular wires and to better understand their charge-transport behaviour and mechanism, have limitations in accuracy and computational cost. Further research is required to develop faster and more precise methods that can yield information on how charge transport properties are impacted by changes in the chemical structure of a molecular wire. In this study, we report a clear semilogarithmic correlation between charge transport efficiency and nuclear magnetic resonance chemical shifts in multiple series of molecular wires, also accounting for the presence of chemical substituents. The NMR data was used to inform a simple tight-binding model that accurately captures the experimental single-molecule conductance values, especially useful in this case as more sophisticated density functional theory calculations fail due to inherent limitations. Our study demonstrates the potential of NMR spectroscopy as a valuable tool for characterising, rationalising, and gaining additional insights on the charge transport properties of single-molecule junctions.

Fluorinated Isoindolinone-Based Glucosylceramide Synthase Inhibitors with Low Human Dose Projections

Inhibition of glucosylceramide synthase (GCS) has been proposed as a therapeutic strategy for the treatment of Parkinson's Disease (PD), particularly in patients where glycosphingolipid accumulation and lysosomal impairment are thought to be contributing to disease progression. Herein, we report the late-stage optimization of an orally bioavailable and CNS penetrant isoindolinone class of GCS inhibitors. Starting from advanced lead 1, we describe efforts to identify an improved compound with a lower human dose projection, minimal P-glycoprotein (P-gp) efflux, and acceptable pregnane X receptor (PXR) profile through fluorine substitution. Our strategy involved the use of predicted volume ligand efficiency to advance compounds with greater potential for low human doses down our screening funnel. We also applied minimized electrostatic potentials (Vmin) calculations for hydrogen bond acceptor sites to rationalize P-gp SAR. Together, our strategies enabled the alignment of a lower human dose with reduced P-gp efflux, and favorable PXR selectivity for the discovery of compound 12.

Lessons learnt from the COVID-19 pandemic in selected countries to inform strengthening of public health systems: a qualitative study

INTRODUCTION

The COVID-19 pandemic has prompted governments internationally to consider strengthening their public health systems. To support the work of Ireland's Public Health Reform Expert Advisory Group, the Health Information and Quality Authority, an independent governmental agency, was asked to describe the lessons learnt regarding the public health response to COVID-19 internationally and the applicability of this response for future pandemic preparedness.

METHODS

Semi-structured interviews with key public health representatives from nine countries were conducted. Interviews were conducted in March and April 2022 remotely via Zoom and were recorded. Notes were taken by two researchers, and a thematic analysis undertaken.

RESULTS

Lessons learnt from the COVID-19 pandemic related to three main themes: 1) setting policy; 2) delivering public health interventions; and 3) providing effective communication. Real-time surveillance, evidence synthesis, and cross-sectoral collaboration were reported as essential for policy setting; it was noted that having these functions established prior to the pandemic would lead to a more efficient implementation in a health emergency. Delivering public health interventions such as testing, contact tracing, and vaccination were key to limiting and or mitigating the spread of the SARS-CoV-2 virus. However, a number of challenges were highlighted such as staff capacity and burnout, delays in vaccination procurement, and reduced delivery of regular healthcare services. Clear, consistent, and regular communication of the scientific evidence was key to engaging citizens with mitigation strategies. However, these communication strategies had to compete with an infodemic of information being circulated, particularly through social media.

CONCLUSIONS

Overall, functions relating to policy setting, public health interventions, and communication are key to pandemic response. Ideally, these should be established in the preparedness phase so that they can be rapidly scaled-up during a pandemic.

Current preconception care practice in the Netherlands - An evaluation study among birth care professionals

OBJECTIVE

To evaluate the current practice of preconception care in the Netherlands and the perceptions of birth care professionals concerning preconception care.

METHODS

We have developed a digital questionnaire and conducted a cross-sectional study by distributing the questionnaire among 102 organisations: 90 primary care midwifery practices and obstetric departments of 12 hospitals in the Southwest region of the Netherlands between December 2020 and March 2021. One birth care professional per organization was asked to complete the questionnaire. Descriptive statistics were used to present the results.

FINDINGS

Respondents of eighty-three organisations (81.4 %) filled in the questionnaire, of whom 74 respondents were independent primary care midwives and 9 respondents were obstetricians. Preconception care mostly consisted of an individual consultation in which personalized health and lifestyle advice was given. Among the respondents, 44.4 % reported that the organization had a preconception care protocol. The way in which the consultation was carried out, as well as the health and lifestyle related questions asked, differed between respondents. More than 85 % of the respondents inquire about the following possible risk factors for complications: maternal illnesses, obstetric history, folic acid supplement intake, alcohol intake, smoking, substance abuse, hereditary disease, prescription medication, dietary habits, overweight, and birth defects in the family. The respondents acknowledged that preconception care should be offered to all couples who wish to become pregnant, as opposed to offering preconception care only to those with an increased risk of complications. Still, respondents do not receive many questions regarding the preconception period or requests for preconception care consultations.

KEY CONCLUSION

Birth care professionals acknowledge the need for preconception care for all couples. In the Netherlands, preconception care consists mostly of an individual consultation with recommendations for health and lifestyle advice. However, the identification of risk factors varies between birth care professionals and less than half of the respondents indicate that they have a protocol available in their practice. Furthermore, the demand of parents-to-be for preconception care is low. More research, that includes more obstetricians, is necessary to investigate if there is a difference between the care provided by primary care midwives and obstetricians.

IMPLICATIONS FOR PRACTICE

To increase the awareness and uptake of preconception care, it would be prudent to emphasize its importance to parents-to-be and professionals, and actively promote the use of widespread, standardized protocols for birth care professionals.

Magnetic resonance imaging detects white adipose tissue beiging in mice following PDE10A inhibitor treatment

Weight gain is a common harmful side effect of atypical antipsychotics used for schizophrenia treatment. Conversely, treatment with the novel phosphodiesterase-10A (PDE10A) inhibitor MK-8189 in clinical trials led to significant weight reduction, especially in patients with obesity. This study aimed to understand and describe the mechanism underlying this observation, which is essential to guide clinical decisions. We hypothesized that PDE10A inhibition causes beiging of white adipose tissue (WAT), leading to weight loss. Magnetic resonance imaging (MRI) methods were developed, validated, and applied in a diet-induced obesity mouse model treated with a PDE10A inhibitor THPP-6 or vehicle for measurement of fat content and vascularization of adipose tissue. Treated mice showed significantly lower fat fraction in white and brown adipose tissue, and increased perfusion and vascular density in WAT versus vehicle, confirming the hypothesis, and matching the effect of CL-316,243, a compound known to cause adipose tissue beiging. The in vivo findings were validated by qPCR revealing upregulation of Ucp1 and Pcg1-α genes, known markers of WAT beiging, and angiogenesis marker VegfA in the THPP-6 group. This work provides a detailed understanding of the mechanism of action of PDE10A inhibitor treatment on adipose tissue and body weight and will be valuable to guide both the use of MK-8189 in schizophrenia and the potential application of the target for weight loss indication.

Discovery of [11C]MK-8056: A Selective PET Imaging Agent for the Study of mGluR2 Negative Allosteric Modulators

Modification of potent, selective metabotropic glutamate receptor 2 negative allosteric modulator (mGluR₂ NAM) led to a series of analogues with excellent binding affinity, lipophilicity, and suitable physicochemical properties for a PET tracer with convenient chemical handles for incorporation of a ¹¹C or ¹⁸F radiolabel. [¹¹C]MK-8056 was synthesized and evaluated in vivo and demonstrated appropriate affinity, selectivity, and physicochemical properties to be used as a positron emission tomography tracer for mGluR₂.

Pyrazole Ureas as Low Dose, CNS Penetrant Glucosylceramide Synthase Inhibitors for the Treatment of Parkinson's Disease

Parkinson's disease is the second most prevalent progressive neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra. Loss-of-function mutations in GBA, the gene that encodes for the lysosomal enzyme glucosylcerebrosidase, are a major genetic risk factor for the development of Parkinson's disease potentially through the accumulation of glucosylceramide and glucosylsphingosine in the CNS. A therapeutic strategy to reduce glycosphingolipid accumulation in the CNS would entail inhibition of the enzyme responsible for their synthesis, glucosylceramide synthase (GCS). Herein, we report the optimization of a bicyclic pyrazole amide GCS inhibitor discovered through HTS to low dose, oral, CNS penetrant, bicyclic pyrazole urea GCSi's with in vivo activity in mouse models and ex vivo activity in iPSC neuronal models of synucleinopathy and lysosomal dysfunction. This was accomplished through the judicious use of parallel medicinal chemistry, direct-to-biology screening, physics-based rationalization of transporter profiles, pharmacophore modeling, and use a novel metric: volume ligand efficiency.

Discovery of MK-8189, a Highly Potent and Selective PDE10A Inhibitor for the Treatment of Schizophrenia

PDE10A is an important regulator of striatal signaling that, when inhibited, can normalize dysfunctional activity. Given the involvement of dysfunctional striatal activity with schizophrenia, PDE10A inhibition represents a potentially novel means for its treatment. With the goal of developing PDE10A inhibitors, early optimization of a fragment hit through rational design led to a series of potent pyrimidine PDE10A inhibitors that required further improvements in physicochemical properties, off-target activities, and pharmacokinetics. Herein we describe the discovery of an isomeric pyrimidine series that addresses the liabilities seen with earlier compounds and resulted in the invention of compound 18 (MK-8189), which is currently in Phase 2b clinical development for the treatment of schizophrenia.

From Fairies to Giants: Untangling the Effect of Body Size, Phylogeny, and Ecology on Vertebral Bone Microstructure of Xenarthran Mammals

Trabecular bone is a spongy bone tissue that serves as a scaffolding-like support inside many skeletal elements. Previous research found allometric variation in some aspects of trabecular bone architecture (TBA) and bone microstructure, whereas others scale isometrically. However, most of these studies examined very wide size and phylogenetic ranges or focused exclusively on primates or lab mice. We examined the impact of body size on TBA across a smaller size range in the mammalian clade Xenarthra (sloths, armadillos, and anteaters). We µCT-scanned the last six presacral vertebrae of 23 xenarthran specimens (body mass 120 g-35 kg). We collected ten gross-morphology measurements and seven TBA metrics and analyzed them using phylogenetic and nonphylogenetic methods. Most metrics had similar allometries to previous work. However, because ecology and phylogeny align closely in Xenarthra, the phylogenetic methods likely removed some covariance due to ecology; clarifying the impact of ecology on TBA in xenarthrans requires further work. Regressions for Folivora had high P-values and low R-squared values, indicating that the extant sloth sample either is too limited to determine patterns or that the unique way sloths load their vertebral columns causes unusually high TBA variation. The southern three-banded armadillo sits far below the regression lines, which may be related to its ability to roll into a ball. Body size, phylogeny, and ecology impact xenarthran TBA, but parsing these effects is highly complex.

The GBA1 D409V mutation exacerbates synuclein pathology to differing extents in two alpha-synuclein models

Heterozygous mutations in the GBA1 gene – encoding lysosomal glucocerebrosidase (GCase) – are the most common genetic risk factors for Parkinson's disease (PD). Experimental evidence suggests a correlation between decreased GCase activity and accumulation of alpha-synuclein (aSyn). To enable a better understanding of the relationship between aSyn and GCase activity, we developed and characterized two mouse models that investigate aSyn pathology in the context of reduced GCase activity. The first model used constitutive overexpression of wild-type human aSyn in the context of the homozygous GCase activity-reducing D409V mutant form of GBA1. Although increased aSyn pathology and grip strength reductions were observed in this model, the nigrostriatal system remained largely intact. The second model involved injection of aSyn preformed fibrils (PFFs) into the striatum of the homozygous GBA1 D409V knock-in mouse model. The GBA1 D409V mutation did not exacerbate the pathology induced by aSyn PFF injection. This study sheds light on the relationship between aSyn and GCase in mouse models, highlighting the impact of model design on the ability to model a relationship between these proteins in PD-related pathology.

Summary: Phenotyping data for two novel mouse models combining glucocerebrosidase (GCase) deficiencies and alpha-synuclein pathology reveal the extent to which alpha-synuclein pathology is exacerbated by GCase deficiency.

Media coverage of evidence outputs during the COVID-19 pandemic: findings from one national agency

Background

The COVID-19 Evidence Synthesis Team within the Health Information and Quality Authority (HIQA) in Ireland produced a range of evidence-based reports on a broad range of public health topics related to COVID-19. These evidence outputs (EO) arose directly from questions posed by policy makers and clinicians supporting Ireland's National Public Health Emergency Team (NPHET). Findings from these EOs informed the national response to the COVID-19 pandemic in Ireland and influenced international public health guidance. How research findings are presented through domestic news can influence behaviour and risk perceptions.

Methods

We investigated traditional media coverage of nine COVID-19 EOs and associated press releases, published (April to July 2020) by HIQA. NVivo was used for conceptual content analysis of manifest content. ‘Core messages' from each evidence output were proposed and 488 sources from national and regional broadcast, print, and online media were coded at the phrase level. The presence of political and public health actors in coverage were also coded.

Results

Coverage largely did not distort or misrepresent the results of the EOs, however, there was variability in terms of what content was reported on and to what extent different stakeholders were involved in the contextualization of the findings of the EOs. Coverage appeared to focus more on ‘human-interest' stories as opposed to more technical reports (e.g. focusing on viral load, antibodies, testing, etc.). Selective reporting and the variability in the use of quotes from governmental and public health stakeholders changed and contextualized results in different manners than perhaps originally intended in the press release.

Conclusions

Our findings provide a case-study of European media coverage of evidence reports produced by a national agency. Results highlighted several strengths and weaknesses of current communication efforts.

Evaluating rapid review provision to inform policy during the COVID-19 pandemic

Background

Evidence based decision making is central to population health, particularly during a pandemic. Few studies examine the production and use of evidence in decision-making during crisis management. This study describes and evaluates the provision of rapid evidence products by a single agency to support national decision making.

Methods

Semi-structured interviews were conducted with a convenience sample of evidence providers (who gathered and disseminated the required evidence) and service users (policy makers). Interviews were transcribed verbatim and analysed using thematic analysis. Quantitative data of work activity were summarised descriptively.

Results

Three themes were generated from the data: the work, the use and the future, with a fourth theme cross-cutting across these: the team. The work followed clear protocols and was centrally managed. The scope and changing nature of the evidence were highlighted as issues. The service providers reported a strong sense of team work and ‘being in this together', however, the majority of the participants felt that the workload was huge and exhausting and not sustainable long-term. Overall the service users thought the rapid evidence synthesis was indispensable to the decision-making process and had trust and confidence in the work, largely based on existing working relationships with the team. While they recognised that the evidence synthesis support would be an essential component of the continued pandemic response, they did query the sustainability of the process and reflected on the amount of work the team performed.

Conclusions

This evaluation, drawing on qualitative data, has highlighted that, across the services users and evidence providers, the support provided by HIQA was generally perceived as positive. From the service users' perspective, having access to the team was indispensable to the decision making process. However, the sustainability of the work load was identified as a major challenge.

COVID-19 - Interventions and lifestyle factors that prevent infection or minimise progression to severe disease

Background

This evidence summary synthesised the evidence relating to pharmacological and non-pharmacological interventions in the community to prevent COVID-19/progression to severe disease. An additional aim was to identify potentially modifiable lifestyle factors associated with reduced risk of infection/progression to severe disease.

Methods

A systematic search of published peer-reviewed articles and non-peer-reviewed pre-prints was undertaken from 1 January 2020 to 19 April 2021; no language restrictions were applied. All potentially eligible papers were exported to Covidence. Titles/abstracts and full texts were single screened for relevance. Data extraction and quality appraisal of included studies was completed by a single reviewer and checked by a second.

Results

In total, 50 studies, three randomised controlled trials (RCTs), one non-RCT and 46 cohort studies were included. The four included controlled trials tested variations of the pharmacological intervention, ivermectin. While these controlled trials reported a protective effect for ivermectin use, these trials were of poor quality and had serious risk of bias. Across 46 cohort studies, the modifiable lifestyle risk factors identified were obesity, smoking, vitamin D status, physical activity, alcohol consumption and processed meat consumption. These studies reported mixed results in terms of the association between modifiable lifestyle risk factors and poor COVID-19 outcomes.

Conclusions

At the time of writing there is no high quality evidence of benefit to support pharmacological interventions to prevent COVID-19. Although there were mixed results for the risk factors identified, maintenance of healthy weight, smoking cessation, engaging in physical activity and moderation of alcohol and processed meat consumption are likely to be beneficial to health and should continue to be encouraged.

A novel glucosylceramide synthase inhibitor attenuates alpha synuclein pathology and lysosomal dysfunction in preclinical models of synucleinopathy

Mutations in the lysosomal enzyme glucocerebrosidase (GCase, GBA1 gene) are the most common genetic risk factor for developing Parkinson's disease (PD). GCase metabolizes the glycosphingolipids glucosylceramide (GlcCer) and glucosylsphingosine (GlcSph). Mutations in GBA1 reduce enzyme activity and the resulting accumulation of glycosphingolipids may contribute to the underlying pathology of PD, possibly via altering lysosomal function. While reduction of GCase activity exacerbates α-synuclein (α-syn) aggregation, it has not been determined that this effect is the result of altered glycosphingolipid levels and lysosome function or some other effect of altering GCase. The glycosphingolipid GlcCer is synthesized by a single enzyme, glucosylceramide synthase (GCS), and small molecule inhibitors (GCSi) reduce cellular glycosphingolipid levels. In the present studies, we utilize a preformed fibril (PFF) rodent primary neuron in vitro model of α-syn pathology to investigate the relationship between glycosphingolipid levels, α-syn pathology, and lysosomal function. In primary cultures, pharmacological inhibition of GCase and D409V GBA1 mutation enhanced accumulation of glycosphingolipids and insoluble phosphorylated α-syn. Administration of a novel small molecule GCSi, benzoxazole 1 (BZ1), significantly decreased glycosphingolipid concentrations in rodent primary neurons and reduced α-syn pathology. BZ1 rescued lysosomal deficits associated with the D409V GBA1 mutation and α-syn PFF administration, and attenuated α-syn induced neurodegeneration of dopamine neurons. In vivo studies revealed BZ1 had pharmacological activity and reduced glycosphingolipids in the mouse brain to a similar extent observed in neuronal cultures. These data support the hypothesis that reduction of glycosphingolipids through GCS inhibition may impact progression of synucleinopathy and BZ1 is useful tool to further examine this important biology.

Intracranial administration of alpha-synuclein fibrils in A30P-synuclein transgenic mice causes robust synucleinopathy and microglial induction

Synucleinopathies are neurodegenerative disorders involving pathological alpha-synuclein (αSyn) protein, including dementia with Lewy bodies, multiple system atrophy and Parkinson's disease (PD). Current in vivo models of synucleinopathy include transgenic mice overexpressing αSyn variants and methods based on administration of aggregated, exogenous αSyn. Combining these techniques offers the ability to study consequences of introducing pathological αSyn into primed neuronal environments likely to develop synucleinopathy. Herein, we characterize the impacts pre-formed fibrils (PFFs) of recombinant, human αSyn have in mice overexpressing human A30P αSyn, a mutation associated with autosomal dominant PD. A30P mouse brain contains detergent insoluble αSyn biochemically similar to PD brain, and these mice develop Lewy-like synucleinopathy with age. Administration of PFFs in A30P mice resulted in regionally-specific accumulations of phosphorylated synuclein, microglial induction and a motor phenotype that differed from PFF-induced effects in wildtype mice. Surprisingly, PFF-induced losses of tyrosine hydroxylase were similar in A30P and wildtype mice. Thus, the PFF-A30P model recapitulates key aspects of synucleinopathy with induction of microglia, creating an appropriate system for evaluating neurodegenerative therapeutics.

Behavioural relevance of spontaneous, transient brain network interactions in fMRI

How spontaneously fluctuating functional magnetic resonance imaging (fMRI) signals in different brain regions relate to behaviour has been an open question for decades. Correlations in these signals, known as functional connectivity, can be averaged over several minutes of data to provide a stable representation of the functional network architecture for an individual. However, associations between these stable features and behavioural traits have been shown to be dominated by individual differences in anatomy. Here, using kernel learning tools, we propose methods to assess and compare the relation between time-varying functional connectivity, time-averaged functional connectivity, structural brain data, and non-imaging subject behavioural traits. We applied these methods to Human Connectome Project resting-state fMRI data to show that time-varying fMRI functional connectivity, detected at time-scales of a few seconds, has associations with some behavioural traits that are not dominated by anatomy. Despite time-averaged functional connectivity accounting for the largest proportion of variability in the fMRI signal between individuals, we found that some aspects of intelligence could only be explained by time-varying functional connectivity. The finding that time-varying fMRI functional connectivity has a unique relationship to population behavioural variability suggests that it might reflect transient neuronal communication fluctuating around a stable neural architecture.

Why do healthcare professionals fail to escalate as per the early warning system (EWS) protocol? A qualitative evidence synthesis of the barriers and facilitators of escalation

Background

Early warning systems (EWSs) are used to assist clinical judgment in the detection of acute deterioration to avoid or reduce adverse events including unanticipated cardiopulmonary arrest, admission to the intensive care unit and death. Sometimes healthcare professionals (HCPs) do not trigger the alarm and escalate for help according to the EWS protocol and it is unclear why this is the case. The aim of this qualitative evidence synthesis was to answer the question ‘why do HCPs fail to escalate care according to EWS protocols?’ The findings will inform the update of the National Clinical Effectiveness Committee (NCEC) National Clinical Guideline No. 1 Irish National Early Warning System (INEWS).

Methods

A systematic search of the published and grey literature was conducted (until February 2018). Data extraction and quality appraisal were conducted by two reviewers independently using standardised data extraction forms and quality appraisal tools. A thematic synthesis was conducted by two reviewers of the qualitative studies included and categorised into the barriers and facilitators of escalation. GRADE CERQual was used to assess the certainty of the evidence.

Results

Eighteen studies incorporating a variety of HCPs across seven countries were included. The barriers and facilitators to the escalation of care according to EWS protocols were developed into five overarching themes: Governance, Rapid Response Team (RRT) Response, Professional Boundaries, Clinical Experience, and EWS parameters. Barriers to escalation included: Lack of Standardisation, Resources, Lack of accountability, RRT behaviours, Fear, Hierarchy, Increased Conflict, Over confidence, Lack of confidence, and Patient variability. Facilitators included: Accountability, Standardisation, Resources, RRT behaviours, Expertise, Additional support, License to escalate, Bridge across boundaries, Clinical confidence, empowerment, Clinical judgment, and a tool for detecting deterioration. These are all individual yet inter-related barriers and facilitators to escalation.

Conclusions

The findings of this qualitative evidence synthesis provide insight into the real world experience of HCPs when using EWSs. This in turn has the potential to inform policy-makers and HCPs as well as hospital management about emergency response system-related issues in practice and the changes needed to address barriers and facilitators and improve patient safety and quality of care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-021-00403-9.

Beyond Description: The Many Facets of Dental Biomechanics

Teeth lie at the interface between an animal and its environment and, with some exceptions, act as a major component of resource procurement through food acquisition and processing. Therefore, the shape of a tooth is closely tied to the type of food being eaten. This tight relationship is of use to biologists describing the natural history of species and given the high instance of tooth preservation in the fossil record, is especially useful for paleontologists. However, correlating gross tooth morphology to diet is only part of the story, and much more can be learned through the study of dental biomechanics. We can explore the mechanics of how teeth work, how different shapes evolved, and the underlying forces that constrain tooth shape. This review aims to provide an overview of the research on dental biomechanics, in both mammalian and non-mammalian teeth, and to synthesize two main approaches to dental biomechanics to develop an integrative framework for classifying and evaluating dental functional morphology. This framework relates food material properties to the dynamics of food processing, in particular how teeth transfer energy to food items, and how these mechanical considerations may have shaped the evolution of tooth morphology. We also review advances in technology and new techniques that have allowed more in-depth studies of tooth form and function.

MK-8719, a Novel and Selective O-GlcNAcase Inhibitor That Reduces the Formation of Pathological Tau and Ameliorates Neurodegeneration in a Mouse Model of Tauopathy

Deposition of hyperphosphorylated and aggregated tau protein in the central nervous system is characteristic of Alzheimer disease and other tauopathies. Tau is subject to O-linked N-acetylglucosamine (O-GlcNAc) modification, and O-GlcNAcylation of tau has been shown to influence tau phosphorylation and aggregation. Inhibition of O-GlcNAcase (OGA), the enzyme that removes O-GlcNAc moieties, is a novel strategy to attenuate the formation of pathologic tau. Here we described the in vitro and in vivo pharmacological properties of a novel and selective OGA inhibitor, MK-8719. In vitro, this compound is a potent inhibitor of the human OGA enzyme with comparable activity against the corresponding enzymes from mouse, rat, and dog. In vivo, oral administration of MK-8719 elevates brain and peripheral blood mononuclear cell O-GlcNAc levels in a dose-dependent manner. In addition, positron emission tomography imaging studies demonstrate robust target engagement of MK-8719 in the brains of rats and rTg4510 mice. In the rTg4510 mouse model of human tauopathy, MK-8719 significantly increases brain O-GlcNAc levels and reduces pathologic tau. The reduction in tau pathology in rTg4510 mice is accompanied by attenuation of brain atrophy, including reduction of forebrain volume loss as revealed by volumetric magnetic resonance imaging analysis. These findings suggest that OGA inhibition may reduce tau pathology in tauopathies. However, since hundreds of O-GlcNAcylated proteins may be influenced by OGA inhibition, it will be critical to understand the physiologic and toxicological consequences of chronic O-GlcNAc elevation in vivo. SIGNIFICANCE STATEMENT: MK-8719 is a novel, selective, and potent O-linked N-acetylglucosamine (O-GlcNAc)-ase (OGA) inhibitor that inhibits OGA enzyme activity across multiple species with comparable in vitro potency. In vivo, MK-8719 elevates brain O-GlcNAc levels, reduces pathological tau, and ameliorates brain atrophy in the rTg4510 mouse model of tauopathy. These findings indicate that OGA inhibition may be a promising therapeutic strategy for the treatment of Alzheimer disease and other tauopathies.

Resistive exercise in astronauts on prolonged spaceflights provides partial protection against spaceflight-induced bone loss

Bone loss in astronauts during spaceflight may be a risk factor for osteoporosis, fractures and renal stone formation. We previously reported that the bisphosphonate alendronate, combined with exercise that included an Advanced Resistive Exercise Device (ARED), can prevent or attenuate group mean declines in areal bone mineral density (aBMD) measured soon after ~ 6-month spaceflights aboard the International Space Station (ISS). It is unclear however if the beneficial effects on postflight aBMD were due to individual or combined effects of alendronate and ARED. Hence, 10 additional ISS astronauts were recruited who used the ARED (ARED group) without drug administration using similar measurements in the previous study, i.e., densitometry, biochemical assays and analysis of finite element (FE) models. In addition densitometry data (DXA and QCT only) were compared to published data from crewmembers (n = 14-18) flown prior to in-flight access to the ARED (Pre-ARED). Group mean changes from preflight (± SD %) were used to evaluate effects of countermeasures as sequentially modified on the ISS (i.e., Pre-ARED vs. ARED; ARED vs. Bis+ARED). Spaceflight durations were not significantly different between groups. Postflight bone density measurements were significantly reduced from preflight in the Pre-ARED group. As previously reported, combined Bis+ARED prevented declines in all DXA and QCT hip densitometry and in estimates of FE hip strengths; increased the aBMD of lumbar spine; and prevented elevations in urinary markers for bone resorption during spaceflight. ARED without alendronate partially attenuated declines in bone mass but did not suppress biomarkers for bone resorption or prevent trabecular bone loss. Resistive exercise in the ARED group did not prevent declines in hip trabecular vBMD, but prevented reductions in cortical vBMD of the femoral neck, in FE estimate of hip strength for non-linear stance (NLS) and in aBMD of the femoral neck. We conclude that a bisphosphonate, when combined with resistive exercise, enhances the preservation of bone mass because of the added suppression of bone resorption in trabecular bone compartment not evident with ARED alone.

LRRK2 inhibition prevents endolysosomal deficits seen in human Parkinson's disease

LRRK2 has been implicated in endolysosomal function and likely plays a central role in idiopathic Parkinson’s disease (iPD). In iPD, dopaminergic neurons within the substantia nigra are characterized by increased LRRK2 kinase activity, endolysosomal deficits, and accumulation of autophagic vesicles with incompletely degraded substrates, including α-synuclein. Although LRRK2 has been implicated in endolysosomal and autophagic function, it remains unclear whether inhibition of LRRK2 kinase activity can prevent endolysosomal deficits or reduce dopaminergic neurodegeneration. In this study, we characterized the endolysosomal and autophagic defects in surviving dopaminergic neurons of iPD patient brain tissue. We next showed that these defects could be reproduced reliably in vivo using the rotenone model of iPD. Results suggested that there was impaired endosomal maturation, resulting in lysosomal dysfunction and deficits in protein degradation. A highly selective, brain-penetrant LRRK2 kinase inhibitor not only improved apparent endosomal maturation and lysosomal function, but also prevented rotenone-induced neurodegeneration in vivo. The fact that a LRRK2 kinase inhibitor was capable of preventing the neuropathological and endolysosomal abnormalities observed in human iPD suggests that LRRK2 inhibitors may have broad therapeutic utility in iPD, not only in those who carry a LRRK2 mutation.

P5730Do hypertensive women with coronary artery disease benefit from lowering systolic blood pressure under 130 mmHg? Long-term mortality in the INternational VErapamil SR-trandolapril STudy (INVEST)

Background

Hypertension (HTN) and coronary artery disease (CAD) are a prevalent combination in women, however limited data are available to guide blood pressure (BP) management. We hypothesize older women with HTN and CAD may not derive the same prognostic benefit from systolic BP (SBP) lowering <130 mmHg.

Purpose

To investigate the long-term mortality implications of different achieved SBP levels in hypertensive women with CAD.

Methods

Long-term, all-cause mortality data were analyzed for 9216 women, stratified by risk attributable to clinical severity of CAD (women with prior myocardial infarction or revascularization considered at high, all others at low risk) and by age (50 - <65 or ≥65 yo). The prognostic impact of achieving mean in-trial SBP <130 (referent group) was compared with 130 to <140 and ≥140 mmHg using Cox proportional hazards, adjusting for demographic and clinical characteristics.

Results

During 108,838 person-years of follow-up, 2945 deaths occurred. High risk women (n=3011) had increased long-term mortality in comparison to low risk women (n=6205) (adjusted HR 1.38, CI 1.28–1.5, p<0.001). Within risk groups, crude mortality percentages decreased according to BP values (table). As expected, high risk women were more likely to be ≥65 yo (68.68% vs. 50.51%, p<0.0001) or have SBP ≥140 mmHg (43.08% vs. 31.18%, p<0.0001). In adjusted analyses, an SBP ≥140 mmHg was associated with worse outcomes than SBP <130 mmHg in the entire cohort (HR 1.3, CI 1.2–1.5, p<0.0001) and when stratifying by risk (low risk group, HR = 1.47, CI 1.28–1.7, p<0.0001; high risk group, HR = 1.71, CI 1.01–1.35, p=0.03). In analyses stratified by age and risk, women ≥65 years and at high risk had decreased mortality in the 130 - <140 SBP category vs. <130 mmHg (HR 0.812, 95% CI 0.689–0.957, p=0.0133; figure).

Women and deaths by risk and SBP group Group SBP category Women (n) Mortality (n) Mortality (%) High risk <130 773 338 44 130–<140 941 414 44 ≥140 1297 694 54 Low risk <130 2187 390 18 130–<140 2083 451 22 ≥140 1935 658 34 SBP = systolic blood pressure; n = number; % = percent per each group.

Mortality adjusted HRs

Conclusion

In women ≥65 yo with hypertension and prior myocardial infarction and/or coronary revascularization enrolled in INVEST, a SBP between 130 to <140 mmHg was associated with lower all-cause, long-term mortality versus SBP <130 mmHg.

Acknowledgement/Funding

The main INVEST (International Verapamil [SR]/Trandolapril Study) was funded by grants from BASF Pharma, Ludwigshafen, Germany; Abbott Laboratories, A

Evidence supporting the best clinical management of patients with multimorbidity and polypharmacy: a systematic guideline review and expert consensus

The complexity and heterogeneity of patients with multimorbidity and polypharmacy renders traditional disease-oriented guidelines often inadequate and complicates clinical decision making. To address this challenge, guidelines have been developed on multimorbidity or polypharmacy. To systematically analyse their recommendations, we conducted a systematic guideline review using the Ariadne principles for managing multimorbidity as analytical framework. The information synthesis included a multistep consensus process involving 18 multidisciplinary experts from seven countries. We included eight guidelines (four each on multimorbidity and polypharmacy) and extracted about 250 recommendations. The guideline addressed (i) the identification of the target population (risk factors); (ii) the assessment of interacting conditions and treatments: medical history, clinical and psychosocial assessment including physiological status and frailty, reviews of medication and encounters with healthcare providers highlighting informational continuity; (iii) the need to incorporate patient preferences and goal setting: eliciting preferences and expectations, the process of shared decision making in relation to treatment options and the level of involvement of patients and carers; (iv) individualized management: guiding principles on optimization of treatment benefits over possible harms, treatment communication and the information content of medication/care plans; (v) monitoring and follow-up: strategies in care planning, self-management and medication-related aspects, communication with patients including safety instructions and adherence, coordination of care regarding referral and discharge management, medication appropriateness and safety concerns. The spectrum of clinical and self-management issues varied from guiding principles to specific recommendations and tools providing actionable support. The limited availability of reliable risk prediction models, feasible interventions of proven effectiveness and decision aids, and limited consensus on appropriate outcomes of care highlight major research deficits. An integrated approach to both multimorbidity and polypharmacy should be considered in future guidelines.

Leveraging the utility of pharmacogenomics in psychiatry through clinical decision support: a focus group study

BACKGROUND

Pharmacogenomics is starting to build momentum in clinical utility, perhaps the most in mental and behavioral healthcare. However, efficient delivery of this information to the point of prescribing remains a significant challenge. Clinical decision support has an opportunity to address this void by integrating pharmacogenomics into the clinician workflow.

METHODS

To address the specific needs of mental health clinicians at the point of care, we conducted 3 focus groups with a total of 16 mental health clinicians. Each 1-h focus group was designed to identify the desired clinical decision support features, with a particular interest in pharmacogenomics, and potential negative or unintended consequences of clinical decision support integration at the point of care in a mental healthcare setting. We implemented an iterative design to expand upon knowledge generated in prior focus groups. The results from the guided discussion in the first focus group were used to develop a mental health clinical decision support prototype. This prototype was then presented during the next two focus groups to drive the discussion.

RESULTS

This study has identified main themes related to the desired clinical decision support features of mental health clinicians, the use of pharmacogenomics in practice, and unintended and negative consequences of clinical decision support integration at the point of care. Clinicians desire a more complete picture of the medication history of patients and guidance to choose medications in relation to cost, insurance coverage, and pharmacogenetics interactions. Mental health clinicians agreed that pharmacogenetics is useful and impacts their prescribing decisions when the data are available. Several negative consequences of clinical decision support integration were identified including alert fatigue and frustration using the tool. Several points of contention were related to the integration of the clinical decision support with the electronic health record, including bidirectional flow of information, speed, location within workflow, and potential incompleteness of information.

CONCLUSIONS

We have identified general and unique considerations of mental health clinicians with regard to clinical decision support. Clinical decision support that incorporates desired features while avoiding negative and unintended consequences will increase clinician usage and will have the potential to improve the care of patients.

Barriers and facilitators to attendance at Type 2 diabetes structured education programmes: a qualitative study of educators and attendees

AIMS

Attendance at structured diabetes education has been recommended internationally for all people with Type 2 diabetes. However, attendance rates are consistently low. This qualitative study aimed to explore experiences of attending and delivering Type 2 diabetes structured education programmes in Ireland and barriers and facilitators to attendance.

METHODS

People with Type 2 diabetes who had attended one of the three programmes delivered in Ireland and educators from the three programmes took part in semi-structured telephone interviews. Interviews were audio-taped, transcribed and analysed using inductive thematic analysis.

RESULTS

Twelve attendees and 14 educators were interviewed. Two themes were identified in relation to experiences of programme attendance and delivery: 'Structured education: addressing an unmet need' and 'The problem of non-attendance'. The third theme 'Barriers to attendance: can't go, won't go, don't know and poor system flow' outlined how practicalities of attending, lack of knowledge of the existence and benefits, and limited resources and support for education within the diabetes care pathway impacts on attendance. The final theme 'Supporting attendance: healthcare professionals and the diabetes care pathway' describes facilitators to participants' attendance and the strategies educators perceived to be important in increasing attendance.

CONCLUSIONS

Healthcare professionals have an important role in improving attendance at structured diabetes education programmes. Improving attendance may require promotion by healthcare professionals and for education to be better embedded and supported within the diabetes care pathway.

Structure-Guided Design and Procognitive Assessment of a Potent and Selective Phosphodiesterase 2A Inhibitor

Herein we describe the development of a series of pyrazolopyrimidinone phosphodiesterase 2A (PDE2) inhibitors using structure-guided lead identification and design. The series was derived from informed chemotype replacement based on previously identified internal leads. The initially designed compound 3, while potent on PDE2, displayed unsatisfactory selectivity against the other PDE2 isoforms. Compound 3 was subsequently optimized for improved PDE2 activity and isoform selectivity. Insights into the origins of PDE2 selectivity are described and verified using cocrystallography. An optimized lead, 4, demonstrated improved performance in both a rodent and a nonhuman primate cognition model.

Supporting prescribing in Irish primary care: protocol for a non-randomised pilot study of a general practice pharmacist (GPP) intervention to optimise prescribing in primary care

Background

Prescribing for patients taking multiple medicines (i.e. polypharmacy) is challenging for general practitioners (GPs). Limited evidence suggests that the integration of pharmacists into the general practice team could improve the management of these patients. The aim of this study is to develop and test an intervention involving pharmacists, working within GP practices, to optimise prescribing in Ireland, which has a mixed public and private primary healthcare system.

Methods

This non-randomised pilot study will use a mixed-methods approach. Four general practices will be purposively sampled and recruited. A pharmacist will join the practice team for 6 months. They will participate in the management of repeat prescribing and undertake medication reviews (which will address high-risk prescribing and potentially inappropriate prescribing, deprescribing and cost-effective and generic prescribing) with adult patients. Pharmacists will also provide prescribing advice regarding the use of preferred drugs, undertake clinical audits, join practice team meetings and facilitate practice-based education. Throughout the 6-month intervention period, anonymised practice-level medication (e.g. medication changes) and cost data will be collected. A nested Patient Reported Outcome Measure (PROM) study will be undertaken during months 4 and 5 of the 6-month intervention period to explore the impact of the intervention in older adults (aged ≥ 65 years). For this, a sub-set of 50 patients aged ≥ 65 years with significant polypharmacy (≥ 10 repeat medicines) will be recruited from each practice and invited to a medication review with the pharmacist. PROMs and healthcare utilisation data will be collected using patient questionnaires, and a 6-week follow-up review conducted. Acceptability of the intervention will be explored using pre- and post-intervention semi-structured interviews with key stakeholders. Quantitative and qualitative data analysis will be undertaken and an economic evaluation conducted.

Discussion

This non-randomised pilot study will provide evidence regarding the feasibility and potential effectiveness of general practice-based pharmacists in Ireland and provide data on whether a randomised controlled trial of this intervention is indicated. It will also provide a deeper understanding as to how a pharmacist working as part of the general practice team will affect organisational processes and professional relationships in a mixed public and private primary healthcare system.

Early intervention of tau pathology prevents behavioral changes in the rTg4510 mouse model of tauopathy

Although tau pathology, behavioral deficits, and neuronal loss are observed in patients with tauopathies, the relationship between these endpoints has not been clearly established. Here we found that rTg4510 mice, which overexpress human mutant tau in the forebrain, develop progressive age-dependent increases in locomotor activity (LMA), which correlates with neurofibrillary tangle (NFT) pathology, hyperphosphorylated tau levels, and brain atrophy. To further clarify the relationship between these endpoints, we treated the rTg4510 mice with either doxycycline to reduce mutant tau expression or an O-GlcNAcase inhibitor Thiamet G, which has been shown to ameliorate tau pathology in animal models. We found that both doxycycline and Thiamet G treatments starting at 2 months of age prevented the progression of hyperactivity, slowed brain atrophy, and reduced brain hyperphosphorylated tau. In contrast, initiating doxycycline treatment at 4 months reduced neither brain hyperphosphorylated tau nor hyperactivity, further confirming the relationship between these measures. Collectively, our results demonstrate a unique behavioral phenotype in the rTg4510 mouse model of tauopathy that strongly correlates with disease progression, and that early interventions which reduce tau pathology ameliorate the progression of the locomotor dysfunction. These findings suggest that better understanding the relationship between locomotor deficits and tau pathology in the rTg4510 model may improve our understanding of the mechanisms underlying behavioral disturbances in patients with tauopathies.

Indole acids as a novel PDE2 inhibitor chemotype that demonstrate pro-cognitive activity in multiple species

An internal HTS effort identified a novel PDE2 inhibitor series that was subsequently optimized for improved PDE2 activity and off-target selectivity. The optimized lead, compound 4, improved cognitive performance in a rodent novel object recognition task as well as a non-human primate object retrieval task. In addition, co-crystallization studies of close analog of 4 in the PDE2 active site revealed unique binding interactions influencing the high PDE isoform selectivity.

Economic evaluation of chronic disease self-management for people with diabetes: a systematic review

AIMS

To systematically review the evidence on the costs and cost-effectiveness of self-management support interventions for people with diabetes.

BACKGROUND

Self-management support is the provision of education and supportive interventions to increase patients' skills and confidence in managing their health problems, potentially leading to improvements in HbA_1c levels in people with diabetes.

METHODS

Randomized controlled trials, observational studies or economic modelling studies were eligible for inclusion in the review. The target population was adults with diabetes. Interventions had to have a substantial component of self-management support and be compared with routine care. Study quality was evaluated using the Consensus on Health Economic Criteria and International Society of Pharmacoeconomic Outcomes Research questionnaires. A narrative review approach was used.

RESULTS

A total of 16 costing and 21 cost-effectiveness studies of a range of self-management support interventions were identified. There was reasonably consistent evidence across 22 studies evaluating education self-management support programmes suggesting these interventions are cost-effective or superior to usual care. Telemedicine-type interventions were more expensive than usual care and potentially not cost-effective. There was insufficient evidence regarding the other types of self-management interventions, including pharmacist-led and behavioural interventions. The identified studies were predominantly of poor quality, with outcomes based on short-term follow-up data and study designs at high risk of bias.

CONCLUSIONS

Self-management support education programmes may be cost-effective. There was limited evidence regarding other formats of self-management support interventions. The poor quality of many of the studies undermines the evidence base regarding the economic efficiency of self-management support interventions for people with diabetes.

Initial Response by a Native Beetle, Chrysochus auratus (Coleoptera: Chrysomelidae), to a Novel Introduced Host-Plant, Vincetoxicum rossicum (Gentianales: Apocynaceae)

Native insects can form novel associations with introduced invasive plants and use them as a food source. The recent introduction into eastern North America of a nonnative European vine, Vincetoxicum rossicum (Kleopow) Barbar., allows us to examine the initial response of a native chrysomelid beetle, Chrysochus auratus F., that feeds on native plants in the same family as V. rossicum (Apocynaceae). We tested C. auratus on V. rossicum and closely related or co-occurring native plants (Apocynum spp., Asclepias spp., and Solidago canadensis L.) using all life stages of the beetle in lab, garden, and field experiments. Experiments measured feeding (presence or absence and amount), survival, oviposition, and whether previous exposure to V. rossicum in the lab or field affected adult beetle feeding. Beetles fed significantly less on V. rossicum than on native Apocynum hosts. Adult beetles engaged in exploratory feeding on leaves of V. rossicum and survived up to 10 d. Females oviposited on V. rossicum, eggs hatched, and larvae fed initially on the roots; however, no larvae survived beyond second instar. Beetles collected from Apocynum cannabinum L. field sites intermixed with V. rossicum were less likely to feed on this novel nonnative host than those collected from colonies further from and less likely to be exposed to V. rossicum (>5 km). Our experimental work indicates that V. rossicum may act as an oviposition sink for C. auratus and that this native beetle has not adapted to survive on this recently introduced novel host plant.

The dual orexin receptor antagonist, DORA-22, lowers histamine levels in the lateral hypothalamus and prefrontal cortex without lowering hippocampal acetylcholine

Chronic insomnia is defined as a persistent difficulty with sleep initiation maintenance or non-restorative sleep. The therapeutic standard of care for this condition is treatment with gamma-aminobutyric acid (GABA)_A receptor modulators, which promote sleep but are associated with a panoply of side effects, including cognitive and memory impairment. Dual orexin receptor antagonists (DORAs) have recently emerged as an alternative therapeutic approach that acts via a distinct and more selective wake-attenuating mechanism with the potential to be associated with milder side effects. Given their distinct mechanism of action, the current work tested the hypothesis that DORAs and GABA_A receptor modulators differentially regulate neurochemical pathways associated with differences in sleep architecture and cognitive performance induced by these pharmacological mechanisms. Our findings showed that DORA-22 suppresses the release of the wake neurotransmitter histamine in the lateral hypothalamus, prefrontal cortex, and hippocampus with no significant alterations in acetylcholine levels. In contrast, eszopiclone, commonly used as a GABA_A modulator, inhibited acetylcholine secretion across brain regions with variable effects on histamine release depending on the extent of wakefulness induction. In normal waking rats, eszopiclone only transiently suppressed histamine secretion, whereas this suppression was more obvious under caffeine-induced wakefulness. Compared with the GABA_A modulator eszopiclone, DORA-22 elicits a neurotransmitter profile consistent with wake reduction that does not impinge on neurotransmitter levels associated with cognition and rapid eye movement sleep.

Paritaprevir/ritonavir/ombitasvir+dasabuvir plus ribavirin therapy and inhibition of the anticoagulant effect of warfarin: a case report

WHAT IS KNOWN AND OBJECTIVE

Paritaprevir/ritonavir/ombitasvir+dasabuvir (PrOD) is a direct-acting antiviral (DAA) approved for the treatment of chronic hepatitis C virus. We report on a probable interaction between PrOD with ribavirin and warfarin.

CASE DESCRIPTION

Two weeks after the start of PrOD with ribavirin, the patient's international normalized ratio (INR) became subtherapeutic. Eleven weeks into therapy and following a 125% total increase in the weekly warfarin dose, therapeutic INR was achieved. Thirteen days after DAA therapy was completed and discontinued, the patient's INR became critically supratherapeutic.

WHAT IS NEW AND CONCLUSION

Patients on PrOD plus ribavirin with warfarin should have INR followed closely upon initiation and discontinuation of therapy due to a probable drug interaction.

Locally limited inhibition of bone resorption and orthodontic relapse by recombinant osteoprotegerin protein

OBJECTIVES

To determine minimal dose levels required for local inhibition of orthodontic relapse by recombinant OPG protein (OPG-Fc), while also determining effects of injected OPG-Fc on alveolar bone and long bone.

SETTING AND SAMPLE POPULATION

The Department of Orthodontics and Pediatric Dentistry at the University of Michigan. Eighteen male Sprague Dawley rats.

MATERIALS & METHODS

Maxillary molars were moved with nickel-titanium springs and then allowed to relapse in Sprague Dawley rats. Upon appliance removal, animals were injected with a single dose of 1.0 mg/kg OPG-Fc, 0.1 mg/kg OPG-Fc, or phosphate-buffered saline (vehicle) just distal to the molar teeth. Tooth movement measurements were made from stone casts, which were scanned and digitally measured. Alveolar tissues were examined by histology. Micro-computed tomography was used to quantify changes in alveolar and femur bone.

RESULTS

Local injection of OPG-Fc inhibited molar but not incisor relapse, when compared to vehicle-injected animals. No significant differences in alveolar or femur bone were seen between the three treatment groups after 24 days of relapse.

CONCLUSIONS

Our results demonstrate that a single local injection of OPG-Fc effectively inhibits orthodontic relapse, with minimal systemic bone metabolic effects. Our results also show that a single injection of OPG-Fc will influence tooth movement only in teeth close to the injection site. These findings indicate that OPG-Fc has potential as a safe and effective pharmacological means to locally control osteoclasts, for uses such as maintaining anchorage during orthodontic tooth movement and preventing orthodontic relapse in humans.

Behavioral and qEEG effects of the PDE10A inhibitor THPP-1 in a novel rhesus model of antipsychotic activity

RATIONALE

Much preclinical data, almost exclusively using rodent, supports the notion that phosphodiesterase 10A (PDE10A) inhibition may offer an alternative to the current standard of care in schizophrenia. However, concerns persist regarding the clinical translatability of these models for newer drug classes like PDE10A inhibitors.

OBJECTIVES

We therefore sought to characterize the clinical standard risperidone and the PDE10A inhibitor THPP-1 in nonhuman primate, both alone and when used as a combination therapy.

METHODS

THPP-1 and risperidone were tested in a novel rhesus model of stimulant-induced motor activity (SIMA) and in rhesus electroencephalography (EEG).

RESULTS

Consistent with rodent data, both THPP-1 and risperidone significantly attenuated the stimulant effects in SIMA when administered alone, though some differences were noted. Combination therapy with a low dose of risperidone produced significantly more robust effects. THPP-1 and risperidone also produced a marked reduction of wake cycle time and gamma frequency power in EEG. However, THPP-1 differed from risperidone by reducing spectral power of lower frequencies (delta).

CONCLUSIONS

SIMA results suggest that PDE10A inhibition produces antipsychotic-like effects in higher species, and that combination therapy with PDE10A inhibitors may produce more robust efficacy compared to monotherapies. EEG and qEEG results confirm that PDE10A inhibition does share some central signaling effects with clinically effective antipsychotics. The present combination therapy results may carry implications for the manner in which clinical testing of PDE10A inhibitors is conducted.

How reliable are MEG resting-state connectivity metrics?

MEG offers dynamic and spectral resolution for resting-state connectivity which is unavailable in fMRI. However, there are a wide range of available network estimation methods for MEG, and little in the way of existing guidance on which ones to employ. In this technical note, we investigate the extent to which many popular measures of stationary connectivity are suitable for use in resting-state MEG, localising magnetic sources with a scalar beamformer. We use as empirical criteria that network measures for individual subjects should be repeatable, and that group-level connectivity estimation shows good reproducibility. Using publically-available data from the Human Connectome Project, we test the reliability of 12 network estimation techniques against these criteria. We find that the impact of magnetic field spread or spatial leakage artefact is profound, creates a major confound for many connectivity measures, and can artificially inflate measures of consistency. Among those robust to this effect, we find poor test-retest reliability in phase- or coherence-based metrics such as the phase lag index or the imaginary part of coherency. The most consistent methods for stationary connectivity estimation over all of our tests are simple amplitude envelope correlation and partial correlation measures.

Task-free MRI predicts individual differences in brain activity during task performance

When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent to the brain and can be predicted from task-independent measurements collected at rest. Using a large set of task conditions, spanning several behavioral domains, we train a simple model that relates task-independent measurements to task activity and evaluate the model by predicting task activation maps for unseen subjects using magnetic resonance imaging. Our model can accurately predict individual differences in brain activity and highlights a coupling between brain connectivity and function that can be captured at the level of individual subjects.

Discovery of pyrazolopyrimidine phosphodiesterase 10A inhibitors for the treatment of schizophrenia

Herein, we present the identification of a novel class of pyrazolopyrimidine phosphodiesterase 10A (PDE10A) inhibitors. Beginning with a lead molecule (1) identified through a fragment-based drug discovery (FBDD) effort, lead optimization was enabled by rational design, X-ray crystallography, metabolic and off-target profiling, and fragment scaffold-hopping. We highlight the discovery of PyP-1, a potent, highly selective, and orally bioavailable pyrazolopyrimidine inhibitor of PDE10A. PyP-1 exhibits sub-nanomolar potency (PDE10A Ki=0.23nM), excellent pharmacokinetic (PK) and physicochemical properties, and a clean off-target profile. It displays dose-dependent efficacy in numerous pharmacodynamic (PD) assays that measure potential for anti-psychotic activity and cognitive improvement. PyP-1 also has a clean preclinical profile with respect to cataleptic potential in rats, prolactin secretion, and weight gain, common adverse events associated with currently marketed therapeutics. Further, PyP-1 displays in vivo preclinical target engagement as measured by PET enzyme occupancy in concert with [(11)C]MK-8193, a novel PDE10A PET tracer.

Six-year follow-up of the SPHERE RCT: secondary prevention of heart disease in general practice

OBJECTIVE

To determine the long-term effectiveness of a complex intervention in primary care aimed at improving outcomes for patients with coronary heart disease.

DESIGN

A 6-year follow-up of a cluster randomised controlled trial, which found after 18 months that both total and cardiovascular hospital admissions were significantly reduced in intervention practices (8% absolute reduction).

SETTING

48 general practices in the Republic of Ireland and Northern Ireland.

PARTICIPANTS

903 patients with established coronary heart disease at baseline in the original trial.

INTERVENTION

The original intervention consisted of tailored practice and patient plans; training sessions for practitioners in medication prescribing and behavioural change; and regular patient recall system. Control practices provided usual care. Following the intervention period, all supports from the research team to intervention practices ceased.

PRIMARY OUTCOME

hospital admissions, all cause and cardiovascular; secondary outcomes: mortality; blood pressure and cholesterol control.

RESULTS

At 6-year follow-up, data were collected from practice records of 696 patients (77%). For those who had died, we censored their data at the point of death and cause of death was established. There were no significant differences between the intervention and control practices in either total (OR 0.83 (95% CI 0.54 to 1.28)) or cardiovascular hospital admissions (OR 0.91 (95% CI 0.49 to 1.65)). We confirmed mortality status of 886 of the original 903 patients (98%). There were no significant differences in mortality (15% in intervention and 16% in control) or in the proportions of patients above target control for systolic blood pressure or total cholesterol.

CONCLUSIONS

Initial significant differences in the numbers of total and cardiovascular hospital admissions were not maintained at 6 years and no differences were found in mortality or blood pressure and cholesterol control. Policymakers need to continue to assess the effectiveness of previously efficacious programmes.

TRIAL REGISTRATION NUMBER

Current Controlled Trials ISRCTN24081411.