Enthalpy-Driven Stabilization of Transthyretin by AG10 Mimics a Naturally Occurring Genetic Variant That Protects from Transthyretin Amyloidosis

Transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) is a fatal disease with no available disease-modifying therapies. While pathogenic TTR mutations (TTRm) destabilize TTR tetramers, the T119M variant stabilizes TTRm and prevents disease. A comparison of potency for leading TTR stabilizers in clinic and structural features important for effective TTR stabilization is lacking. Here, we found that molecular interactions reflected in better binding enthalpy may be critical for development of TTR stabilizers with improved potency and selectivity. Our studies provide mechanistic insights into the unique binding mode of the TTR stabilizer, AG10, which could be attributed to mimicking the stabilizing T119M variant. Because of the lack of animal models for ATTR-CM, we developed an in vivo system in dogs which proved appropriate for assessing the pharmacokinetics-pharmacodynamics profile of TTR stabilizers. In addition to stabilizing TTR, we hypothesize that optimizing the binding enthalpy could have implications for designing therapeutic agents for other amyloid diseases.

Family health and income: A two-sample replication

The current study examined psychological and family health predictors of change over time in household income, using data from longitudinal studies of African American (N = 889, 93.5% female) and Mexican origin (N = 674, 100% female) families. Participants self-reported their household income, as well as their emotional, personality, and cognitive resources. Participant behavioral and physical resources were coded from observed family interactions. Although income did not predict change in any personal resources, all five classes of personal resources (i.e., emotional, personality, cognitive, behavioral, physical) predicted change in income across a 10-year span (Study 1) and a 6-year span (Study 2). Income is potentially caused by these personal resources, or both income and these personal resources share a common cause. The dominant approach of assuming income causes personal and family health needs stronger support. (PsycINFO Database Record

Predicting in-hospital mortality in older general surgical patients

Introduction A significant number of emergency general surgical admissions occur in older patients. Clinical decision making in this group is challenging and current risk prediction tools extrapolate data from cohorts of younger patients. This is the first UK study to examine risk factors predicting in-hospital mortality in older acute surgical patients undergoing comprehensive geriatric assessment. Methods This was a prospective study of consecutive patients aged ≥75 years admitted non-electively to general surgery wards between September 2014 and February 2017 who were reviewed by an elderly medicine in-reach service. Results A total of 577 patients were included with a mean age of 82.9 years. There was a female predominance (56%). The majority were living at home alone or with carers (93%) and most were independent in basic activities of daily living (79%). Over two-thirds (69%) were mobile with no walking aids or use of a walking stick and overt here-quarters (79%) had no cognitive impairment. Seventy-seven per cent of patients were managed non-operatively. The in-hospital mortality rate was 6.9%. Female sex (p=0.031), dependence in activities of daily living (p<0.001), cognitive impairment (p<0.001) and incontinence (p<0.001) were predictors of in-hospital mortality. ASA (American Society of Anesthesiologists) grade ≥3 was also associated with increased in-hospital mortality (odds ratio: 5.3, 95% confidence interval: 2.6-10.7). Conclusions Older general surgical patients present a high level of complexity. This study highlights the predictive role of mobility, functional and cognitive impairment when assessing this population. Accurate risk stratification requires global assessment by teams experienced in care of the older patient rather than the traditional focus on co-morbidities.

Community health workers and accountability: reflections from an international "think-in"

Community health workers (CHWs) are frequently put forward as a remedy for lack of health system capacity, including challenges associated with health service coverage and with low community engagement in the health system, and expected to enhance or embody health system accountability. During a ‘think in’, held in June of 2017, a diverse group of practitioners and researchers discussed the topic of CHWs and their possible roles in a larger “accountability ecosystem.” This jointly authored commentary resulted from our deliberations. While CHWs are often conceptualized as cogs in a mechanistic health delivery system, at the end of the day, CHWs are people embedded in families, communities, and the health system. CHWs’ social position and professional role influence how they are treated and trusted by the health sector and by community members, as well as when, where, and how they can exercise agency and promote accountability. To that end, we put forward several propositions for further conceptual development and research related to the question of CHWs and accountability.

Community health workers and accountability: reflections from an international "think-in"

Community health workers (CHWs) are frequently put forward as a remedy for lack of health system capacity, including challenges associated with health service coverage and with low community engagement in the health system, and expected to enhance or embody health system accountability. During a 'think in', held in June of 2017, a diverse group of practitioners and researchers discussed the topic of CHWs and their possible roles in a larger "accountability ecosystem." This jointly authored commentary resulted from our deliberations. While CHWs are often conceptualized as cogs in a mechanistic health delivery system, at the end of the day, CHWs are people embedded in families, communities, and the health system. CHWs' social position and professional role influence how they are treated and trusted by the health sector and by community members, as well as when, where, and how they can exercise agency and promote accountability. To that end, we put forward several propositions for further conceptual development and research related to the question of CHWs and accountability.

Is a Positive Relationship Between Fertility and Economic Development Emerging at the Sub-National Regional Level? Theoretical Considerations and Evidence from Europe

Evidence for nation-states suggests that the long-standing negative relationship between fertility and economic development might turn positive at high levels of development. The robustness of the reversal continues to be debated. We add to this discussion from a novel angle by considering whether such a reversal could also occur at the sub-national level within highly developed countries. Our contributions are both theoretical and empirical. We first discuss important trends which might foster the emergence of a positive fertility-development relationship across regions of highly developed countries. These include shifts in family policies, changes in the spatial organisation of the economic sphere, and selective international and internal migration processes. In order to explore whether we observe tendencies towards a reversal, we investigate data covering 20 European countries subdivided in 256 regions between 1990 and 2012. We document a weakening of the negative relationship between fertility and economic development within many countries, and among some countries the emergence of a positive relationship. These findings do not seem to be driven by postponement effects alone. However, there is substantial variation in the fertility and the economic development levels at which such tendencies towards a reversal are observed.

Knowledge Acquisition for Expert Systems: Experience in Leukaemia Diagnosis

EMYCIN was used to develop an expert system for the interpretation of immunological data obtained in the cell surface phenotyping of leukaemia. Access to a recognised expert, and a large quantity of data on the leukaemias, has facilitated a systematic study of knowledge acquisition and knowledge base refinement based on tape recorded commentaries made by the expert. System performance was analysed at six stages in its development, and ways in which it differed from that of the human diagnostician were identified. Among the most suggestive observations were differences in the way that “undiagnosable” patients were treated and a failure of the elicitation technique to reveal structural aspects of the task. The tools and techniques of knowledge engineering are a significant advance, but a better methodology for developing high quality knowledge bases is needed.

Abstract P4-08-01: Not presented

This abstract was not presented at the symposium.

Alternatives to Bayes?

Recent proposals have suggested that rule-based systems of diagnostic inference are an attractive medium for computer-aided diagnosis, in part because clinicians find their behaviour easy to understand. Bayesian systems have been more prominent in this field to date, but no direct comparison of their clinical abilities has been reported. A rule-based system that was closely modelled on clinical thinking is described and a quantitative comparison with a successful Bayesian system for the diagnosis of »dyspepsia« is presented. The results suggest that the rule-based approach may have considerable potential as an efficient alternative to Bayesian inference.

RAGs: A Novel Approach to Computerized Genetic Risk Assessment and Decision Support from Pedigrees

Objectives: To assist general practitioners in evaluating patients’ genetic risk of cancer on the basis of family history data.

Methods: A new computer application, RAGs (Risk Assessment in Genetics), has been developed to help doctors create graphical family trees and assess the genetic risk of breast and colorectal cancer. RAGs possesses two features that distinguish it from similar software: (i) a user-centred design, which takes into account the requirements of the doctor-patient encounter; (ii) effective and accessible risk reporting by employing qualitative evidence for or against increased risk, which is more easily understood than numerical probabilities. The system allows any rule-based genetic risk guideline to be implemented, and may be readily modified to cater for the varying degrees of information required by different specialists.

Results: RAGs permits fast, accurate data entry, and results in more appropriate management decisions than those made via other techniques. In addition, RAGs enables both the clinician and the patient to understand how it arrives at its conclusions, since the use of qualitative evidence allows the program to provide explanations for its reasoning.

Conclusions: The RAGs system promises to help practitioners be more effective gatekeepers to genetic services. It may empower doctors both to make an informed choice when deciding to refer patients who are at increased genetic risk of breast or colorectal cancer, and to reassure those who are at low risk.

The impact of immunoglobulin in acute HIV infection on the HIV reservoir: a randomized controlled trial

OBJECTIVES

Antiretroviral therapy (ART) during acute HIV infection (AHI) restricts the HIV reservoir, but additional interventions are necessary to induce a cure. Intravenous immunoglobulin (IVIG) is not HIV-specific but is safe and temporarily reduces the HIV reservoir in chronic HIV infection. We present a randomized controlled trial to investigate whether IVIG plus ART in AHI reduces the HIV reservoir and immune activation compared with ART alone.

METHODS

Ten men with AHI (Fiebig II-IV) initiated ART (tenofovir, entricitabine, ritonavir boosted darunavir and raltegravir) at HIV-1 diagnosis and were randomized to ART alone or ART plus 5 days of IVIG, once virally suppressed (week 19). Blood samples were evaluated for viral reservoir, immune activation, immune exhaustion and microbial translocation. Flexible sigmoidoscopy was performed at weeks 19, 24 and 48, and gut proviral DNA and cell numbers determined.

RESULTS

IVIG was well tolerated and no viral blips (> 50 HIV-1 RNA copies/mL) occurred during IVIG therapy. From baseline to week 48, total HIV DNA in peripheral blood mononuclear cells (PBMCs) (cases: -3.7 log₁₀ copies/10⁶ CD4 cells; controls: -3.87 log₁₀ copies/10⁶ CD4 cells) declined with no differences observed between the groups (P = 0.49). Declines were observed in both groups from week 19 to week 48 in total HIV DNA in PBMCs (P = 0.38), serum low copy RNA (P = 0.57) and gut total HIV DNA (P = 0.55), but again there were no significant differences between arms. Biomarkers of immune activation, immune exhaustion and microbial translocation and the CD4:CD8 ratio were similar between arms for all comparisons.

CONCLUSIONS

Although safe, IVIG in AHI did not impact total HIV DNA, immune function or microbial translocation in peripheral blood or gut tissue.