Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Essential role of the Pax5 C-terminal domain in controlling B cell commitment and development

The B cell regulator Pax5 consists of multiple domains whose function we analyzed in vivo by deletion in Pax5. While B lymphopoiesis was minimally affected in mice with homozygous deletion of the octapeptide or partial homeodomain, both sequences were required for optimal B cell development. Deletion of the C-terminal regulatory domain 1 (CRD1) interfered with B cell development, while elimination of CRD2 modestly affected B-lymphopoiesis. Deletion of CRD1 and CRD2 arrested B cell development at an uncommitted pro-B cell stage. Most Pax5-regulated genes required CRD1 or both CRD1 and CRD2 for their activation or repression as these domains induced or eliminated open chromatin at Pax5-activated or Pax5-repressed genes, respectively. Co-immunoprecipitation experiments demonstrated that the activating function of CRD1 is mediated through interaction with the chromatin-remodeling BAF, H3K4-methylating Set1A-COMPASS, and H4K16-acetylating NSL complexes, while its repressing function depends on recruitment of the Sin3-HDAC and MiDAC complexes. These data provide novel molecular insight into how different Pax5 domains regulate gene expression to promote B cell commitment and development.

Enhancers of the PAIR4 regulatory module promote distal VH gene recombination at the Igh locus

While extended loop extrusion across the entire Igh locus controls V_H -DJ_H recombination, local regulatory sequences, such as the PAIR elements, may also activate V_H gene recombination in pro-B-cells. Here, we show that PAIR-associated V_H 8 genes contain a conserved putative regulatory element (V8E) in their downstream sequences. To investigate the function of PAIR4 and its V8.7E, we deleted 890 kb containing all 14 PAIRs in the Igh 5' region, which reduced distal V_H gene recombination over a 100-kb distance on either side of the deletion. Reconstitution by insertion of PAIR4-V8.7E strongly activated distal V_H gene recombination. PAIR4 alone resulted in lower induction of recombination, indicating that PAIR4 and V8.7E function as one regulatory unit. The pro-B-cell-specific activity of PAIR4 depends on CTCF, as mutation of its CTCF-binding site led to sustained PAIR4 activity in pre-B and immature B-cells and to PAIR4 activation in T-cells. Notably, insertion of V8.8E was sufficient to activate V_H gene recombination. Hence, enhancers of the PAIR4-V8.7E module and V8.8E element activate distal V_H gene recombination and thus contribute to the diversification of the BCR repertoire in the context of loop extrusion.

Igh and Igk loci use different folding principles for V gene recombination due to distinct chromosomal architectures of pro-B and pre-B cells

Extended loop extrusion across the immunoglobulin heavy-chain (Igh) locus facilitates V_H-DJ_H recombination following downregulation of the cohesin-release factor Wapl by Pax5, resulting in global changes in the chromosomal architecture of pro-B cells. Here, we demonstrate that chromatin looping and V_K-J_K recombination at the Igk locus were insensitive to Wapl upregulation in pre-B cells. Notably, the Wapl protein was expressed at a 2.2-fold higher level in pre-B cells compared with pro-B cells, which resulted in a distinct chromosomal architecture with normal loop sizes in pre-B cells. High-resolution chromosomal contact analysis of the Igk locus identified multiple internal loops, which likely juxtapose V_K and J_K elements to facilitate V_K-J_K recombination. The higher Wapl expression in Igμ-transgenic pre-B cells prevented extended loop extrusion at the Igh locus, leading to recombination of only the 6 most 3' proximal V_H genes and likely to allelic exclusion of all other V_H genes in pre-B cells. These results suggest that pro-B and pre-B cells with their distinct chromosomal architectures use different chromatin folding principles for V gene recombination, thereby enabling allelic exclusion at the Igh locus, when the Igk locus is recombined.

Performance improvement in sport through vitamin D - a narrative review

OBJECTIVE

It is well known that vitamin D deficiency can lead to various health problems. However, it is not common knowledge among athletes and doctors that vitamin D deficiency is prevalent in sports. This deficiency can severely impact performance, while vitamin D supplementation can alleviate this effect and potentially improve performance.

MATERIALS AND METHODS

This narrative review aims to compile the current state of knowledge about the importance of vitamin D in increasing performance for active people. To this end, we searched the 'Scopus' and 'PubMed' databases for the terms 'vitamin D - athlete - performance' with an end date of 30 June 2022.

RESULTS

Study results indicated that the therapeutic impact of vitamin D on aerobic capacity, recovery, strength and sprint performance remains controversial.

CONCLUSIONS

Based on the previous findings on recovery, strength and performance, 4,000-5,000 IU of vitamin D per day may be a safe dose that can improve athletic performance.

Biallelic PAX5 mutations cause hypogammaglobulinemia, sensorimotor deficits, and autism spectrum disorder

The genetic causes of primary antibody deficiencies and autism spectrum disorder (ASD) are largely unknown. Here, we report a patient with hypogammaglobulinemia and ASD who carries biallelic mutations in the transcription factor PAX5. A patient-specific Pax5 mutant mouse revealed an early B cell developmental block and impaired immune responses as the cause of hypogammaglobulinemia. Pax5 mutant mice displayed behavioral deficits in all ASD domains. The patient and the mouse model showed aberrant cerebellar foliation and severely impaired sensorimotor learning. PAX5 deficiency also caused profound hypoplasia of the substantia nigra and ventral tegmental area due to loss of GABAergic neurons, thus affecting two midbrain hubs, controlling motor function and reward processing, respectively. Heterozygous Pax5 mutant mice exhibited similar anatomic and behavioral abnormalities. Lineage tracing identified Pax5 as a crucial regulator of cerebellar morphogenesis and midbrain GABAergic neurogenesis. These findings reveal new roles of Pax5 in brain development and unravel the underlying mechanism of a novel immunological and neurodevelopmental syndrome.

The impact and experience of cardiac cachexia in advanced heart failure patients and their caregivers

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Northern Ireland Chest Heart & Stroke

Background

Cardiac cachexia is a multifactorial wasting syndrome, which is characterised by unintentional weight loss, a reduction in skeletal muscle mass, and reduced quality of life. There is a paucity of qualitative research outlining the impact and experience of cardiac cachexia in advanced heart failure patients and their caregivers. Research in this area may promote a better understanding of the syndrome, enhance current treatment strategies, and highlight priorities for patient care.

Purpose

To qualitatively investigate the impact and experience of cardiac cachexia in advanced heart failure patients and their caregivers.

Methods

Semi-structured interviews were performed with advanced heart failure (NYHA functional class III-IV) patients meeting diagnostic criteria for cardiac cachexia (number (n) = 8) and their caregivers (n = 5). Interview questions followed a "laddered style approach", with a focus on determining the experience of cachexia for patients and carers, and its impact on their daily lives. Interviews were digitally recorded and transcribed verbatim. Average interview duration was 43 (15-64) minutes. Data were thematically analysed, using the 6-step approach of Braun & Clarke. Themes were developed and refined by several members of the research team to ensure rigor.

Results

Four key themes were developed from the data. 1) "Changed relationship with food and eating": patients with cachexia referred to eating as something they now ‘make’ themselves do without enjoyment, often just to placate their caregiver. Caregivers noted this change in habit and were concerned about inadequate nutritional intake due to the patient’s lack of interest in food. 2) "Not me in the mirror": patients struggled with their appearance and had a negative perception of themselves, linked to their weight loss. Caregivers were similarly aware of the physical changes in their loved ones and emotionally impacted. 3) "Lack of understanding regarding cachexia": despite the patient and caregivers’ concerns, they had a perception that healthcare professionals were just ‘fobbing you off’. Even though weight loss was noted and distressing to patients and caregivers, there was little clinical recognition of it, nor any advice or support from the clinical team regarding management. 4) "Uncertainty regarding the future": patients and caregivers recognised cachexia as a bad sign, and many expressed concerns about their future health and prognosis.

Conclusion

These novel qualitative findings highlight the severe impact of cardiac cachexia on the daily lives of patients and caregivers, and demonstrate their limited understanding of the syndrome. To improve care, professionals need to recognise and discuss cachexia with heart failure patients and caregivers, supporting them to cope with prognostic implications and develop more effective management strategies.

The aspects of sex, age and nationality in winter swimming performance

OBJECTIVE

Winter swimming is a new sport discipline. Very little is known, however, about the sex differences, origin, participation and performance of the world's best winter swimmers. Therefore, the study aimed to investigate sex differences in performance and age. Furthermore, it should be determined which country has the fastest swimmers, the highest numbers of participants and the most successful age group athletes in winter swimming.

SUBJECTS AND METHODS

A total of 6,477 results from the 25 m events of the IWSA (International Winter Swimming Association) World Cups from 2016-2020 was collected from the official website of IWSA. Data were analyzed using a generalized linear model (GLM) with a gamma probability distribution and identity link function. The 25 m events were carried out in head-up breaststroke style, freestyle and butterfly. The nationalities were grouped into six groups, the five nationalities with the highest number of participants in the 25 m competitions and one group with the other nationalities. The mean time of 25 m races by sex and country of the total sample was compared. For the top 10 comparisons, the best ten athletes from the six groups were selected. The mean time of each top 10 groups was compared by sex and nationality.

RESULTS

Men were faster than women for all categories. Swimmers in age group 15-29 years were the fastest, where females were the fastest in age group 15-19 years and males in age group 20-29 years. Women from both Russia and Estonia and men from both Russia and China were the fastest. Both Russian and Chinese males were the fastest in all water categories in the top 10 section in the 25 m events.

CONCLUSIONS

In summary, males were faster than females in the IWSA World Cups between 2016 and 2020. The age group of 15-29 years old athletes was the most successful while females had their age of peak performance earlier than males. Russian and Estonian males and Russian females were the overall fastest in the 25 m events in all water categories. Future studies should investigate the optimal anthropometric characteristics of male and female winter swimming sprint athletes and whether there are distinct areas in Russia, Estonia and China, where many international winter swimming athletes originate.

Effect of two incremental intensity field tests on wellness indices, recovery state, and physical enjoyment in soccer players

OBJECTIVE

Competitive athletes must undergo fitness testing to monitor athlete progress and to create appropriate, progressive training programs. However, fitness testing adds to training stress; therefore, impacts of testing on wellness and recovery must be considered in test selection. This study investigated the effects of two incremental field tests [VAMEVAL test (T-VAM) and 20-m maximum shuttle test (20-m MST)] on wellness, total quality of recovery (TQR) and physical enjoyment (PE) in competitive soccer players.

SUBJECTS AND METHODS

Twenty-two soccer players (20.9±1.5 years) completed two T-VAM and two 20-m MST in a randomized order on separate days with a 1-week interval between tests. TQR and wellness indices (sleep, fatigue, stress and muscle soreness) measures were collected before and 24 hours after each test. Heart rate (HR) was continuously monitored during each test. Rating of perceived exertion (RPE) and PE were assessed after each test.

RESULTS

T-VAM resulted in higher PE, TQR and wellness scores than 20-m MST (p<0.05). T-VAM and 20-m MST resulted in similar HR and maximal aerobic speed. For T-VAM, TQR was correlated (p<0.01) with RPE and wellness indices. For 20-m MST, TQR was correlated (p<0.01) with wellness indices. HRmax and RPE were not correlated with wellness indices, TQR or PE.

CONCLUSIONS

Overall, T-VAM and 20-m MST produced similar aerobic fitness testing results, but athletes responded more favorably to T-VAM. Coaches can use T-VAM for evaluating aerobic fitness while maximizing well-being and physical enjoyment among soccer players.

A Kerr polarization controller

Kerr-effect-induced changes of the polarization state of light are well known in pulsed laser systems. An example is nonlinear polarization rotation, which is critical to the operation of many types of mode-locked lasers. Here, we demonstrate that the Kerr effect in a high-finesse Fabry-Pérot resonator can be utilized to control the polarization of a continuous wave laser. It is shown that a linearly-polarized input field is converted into a left- or right-circularly-polarized field, controlled via the optical power. The observations are explained by Kerr-nonlinearity induced symmetry breaking, which splits the resonance frequencies of degenerate modes with opposite polarization handedness in an otherwise symmetric resonator. The all-optical polarization control is demonstrated at threshold powers down to 7 mW. The physical principle of such Kerr effect-based polarization controllers is generic to high-Q Kerr-nonlinear resonators and could also be implemented in photonic integrated circuits. Beyond polarization control, the spontaneous symmetry breaking of polarization states could be used for polarization filters or highly sensitive polarization sensors when operating close to the symmetry-breaking point.

Hydrogel matrix presence and composition influence drug responses of encapsulated glioblastoma spheroids

Glioblastoma multiforme (GBM) is the most aggressive brain tumor with median patient survival of 12-15 months. To facilitate treatment development, bioengineered GBM models that adequately recapitulate the in vivo tumor microenvironment are needed. Matrix-encapsulated multicellular spheroids represent such model because they recapitulate solid tumor characteristics, such as dimensionality, cell-cell, and cell-matrix interactions. Yet, there is no consensus as to which matrix properties are key to improving the predictive capacity of spheroid-based drug screening platforms. We used a hydrogel-encapsulated GBM spheroid model, where matrix properties were independently altered to investigate their effect on GBM spheroid characteristics and drug responsiveness. We focused on hydrogel degradability, tuned via enzymatically degradable crosslinkers, and hydrogel adhesiveness, tuned via integrin ligands. We observed increased cellular infiltration of GBM spheroids and increased resistance to temozolomide in degradable, adhesive hydrogels compared to spheroids in non-degradable, non-adhesive hydrogels or to free-floating spheroids. Further, a higher infiltration index was noted for spheroids in adhesive compared to non-adhesive degradable hydrogels. For spheroids in degradable hydrogels, we determined that infiltrating cells were more susceptible to temozolomide compared to cells in the spheroid core. The temozolomide susceptibility of the infiltrating cells was independent of integrin adhesion. We could not attribute differential drug responses to differential cellular proliferation or to limited drug penetration into the hydrogel matrix. Our results suggest that cell-matrix interactions guide GBM spheroid drug responsiveness and that further elucidation of these interactions could enable the engineering of more predictive drug screening platforms. STATEMENT OF SIGNIFICANCE: Glioblastoma multiforme (GBM) multicellular spheroids hold promise for drug screening and development as they better mimic in vivo cellular responses to therapeutics compared to monolayer cultures. Traditional spheroid models lack an external extracellular matrix (ECM) and fail to mimic the mechanical, physical, and biochemical cues seen in the GBM microenvironment. While embedding spheroids in hydrogel matrices has been shown to better recapitulate the tumor microenvironment, there is still limited understanding as to the key matrix properties that govern spheroid responsiveness to drugs. Here we decoupled and independently altered matrix properties such as degradability, via an enzymatically degradable peptide crosslinker, and cell adhesion, via an adhesive ligand, giving further insight into what matrix properties contribute to GBM chemoresistance.

The feasibility and acceptability of a virtual six-week psychoeducational intervention for carers of patients with heart failure

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Northern Ireland Chest Heart and Stroke Queen"s University Belfast

Background

Globally, the number of individuals living with heart failure (HF) is increasing, with many living with additional comorbidities and complex health needs. Carers play an invaluable role in helping the patient with self-care at home, taking on the key responsibility for tasks critical in the management and monitoring of HF symptoms. As a result, carers can frequently experience poor quality of life attributed to this caring role, whilst simultaneously managing health problems of their own. Evidence has shown that many of these carers have unmet educational, social and emotional needs, that require urgent support and information.

Purpose

To assess the feasibility and acceptability of a six-week psychoeducational intervention tailored towards carers of patients with HF.

Methods

  The psychoeducational intervention was co-produced with involvement of carers, HF professionals and researchers. It was delivered over six weeks, with four support group sessions and an information booklet tailored specifically to the needs of carers. Carers were identified by the clinical HF team or through social media, with informed consent obtained before inclusion. Due to COVID-19 regulations, the support group sessions were delivered virtually via a secure online app (Zoom). Each session involved a member of the interdisciplinary research team and covered topics including: 1. Understanding HF, 2. Personal wellbeing, 3. Communication and Support, and 4. Practical skills to help manage HF. Validated questionnaires (SF-12, HADS,ZBI,PSS,MSPSS,CPS) measuring carer related outcomes were completed at baseline, at 6 weeks and 3 months post intervention. Qualitative data from focus group post-intervention explored the acceptability of the intervention. Data was analysed using SPSS (version 27) and NVivo (version 11).

Results

 Nine participants consented to participate, six of which were recruited from heart failure clinics, and three volunteered in response to social media advertisements. Two participants, due to personal health reasons, withdrew consent and did not attend the support group sessions. All carers were female, mean age 61 years, four spouses and three adult children. Preliminary qualitative findings show carers recalled information and advice included in the intervention as useful and easy to understand. With the intervention being described as, "a dimension that doesn’t already exist". The majority of participants (n = 5) preferred the convenience and flexibility of the online approach to the intervention, however some participants (n = 2) felt that they would have benefitted more from an in-person approach. A second  support group is currently underway. 

Conclusions

Preliminary results are promising and indicate that carers responded well to an online psychoeducational intervention.

Understanding needs and expectations of heart failure patients and their caregivers regarding digital health - the PASSION-HF project

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): INTERREG-NWE

Background/Introduction

Current heart failure (HF) healthcare provision is not sufficient. Due to demographic changes and subsequent increases in comorbidities, along with unequal distribution of medical care in rural areas, alternative approaches need be sought. The use of eHealth applications has potential to enable patients to become more self-sufficient. The "PASSION-HF" project aims to develop an interactive decision-making system – a virtual doctor – that provides solutions based on current guidelines and artificial intelligence. Patient independence is maximized through 24/7 access to personalized HF-management. Furthermore, the application defines decision points, where medical professionals need to be included.

Purpose

To understand needs and expectations of HF patients and their informal caregivers in regard to a virtual doctor.

Methods

We conducted an exploratory mixed-methods study within the Netherlands, UK, Ireland and Germany. Semi-structured qualitative interviews were supplemented by a standardized questionnaire. The interviews focused on i) acceptance and motivation to use a virtual doctor and ii) experience and perception of current health care provision. The interviews were analysed using the content analysis according to Mayring (2010) with the help of "ATLAS.TI" software. Additional information about the role of informal caregivers, technology acceptance and decision-making processes was collected via questionnaires.

Results

A total of 49 patients and 33 informal caregivers were interviewed. Most patients were male (76%), aged between 60 and 69 years (43%). Three key themes were identified in regard to an interactive decision-making system: 1) Reassurance, because patients felt uncertain about their condition and their symptoms, they had a strong desire for an application that could monitor their health 24/7, was able to spot deteriorations, before they occured and gave them instant feedback about their current health status; 2) Personalized advice, e.g. patients wanted the virtual doctor to adapt medication, sport activities and food recommendations to their current health status; and 3) Transparency, e.g. patients wanted to know, where the recommendations are coming from and justifications for management modifications. Interview findings also identified that the HF-nurses play a significant role in the care and management of the condition. Across all countries with HF-nurses, they were the primary point of contact, when patients had any HF related concerns. 

Conclusion

The findings provide valuable information for the development and implementation of eHealth solutions. Patients want reassurance, independently of the availability of healthcare services, combined with personalized advice regarding day-to-day management of their HF. For the next step, we are planning a multicentre clinical trial to test the prototype of the application. Here all decisions are examined by a clinical committee and benefits are evaluated.

Prevalence and effect of cardiac cachexia in advanced heart failure patients living in northern ireland

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Northern Ireland Chest Heart and Stroke

Background/Introduction: Cardiac cachexia (CC) is a multifactorial wasting syndrome, resulting in significant weight loss and reduction in muscle mass. This is reflected in a detrimental effect on the patients’ physical condition, quality of life and increases the patient’s risk of premature death. Nonetheless, cardiac cachexia remains frequently unrecognised in clinical practice and therefore understudied.

Purpose

To determine the prevalence and effect of cardiac cachexia in 200 patients with advanced heart failure (NYHA class III-IV) living in Northern Ireland.

Methods

A mixed methods cross sectional study of patients recruited from a regional heart failure centre. A total of 200 patients with NYHA class III-IV heart failure were consented, enrolled and detailed data collected from their records. Anthropometric measures were taken (i.e. measures of lean muscle mass and fat tissue) and each individual completed three validated questionnaires - EQ-5D-5L (quality of life), FACIT-Fatigue and FAACT (various wellbeing subscales).

Results

This population was predominately male (65.5%), with an average age of 74.4 years. Of the 200 NYHA class III-IV patients recruited, 30 were identified as cachectic (15%) Physically, cachectic patients were approximately 25 kg lighter than non-cachectic patients (p &lt; 0.01) with an average BMI of 21.8 ± 4.4. The cachectic group showed significant reductions in mid-upper arm circumference (p &lt; 0.01), skinfold thickness (p &lt; 0.01) and upper arm fat area (p &lt; 0.01), in comparison to the non-cachectic group. Measures of muscle mass were reduced, for example upper arm muscle circumference and area (p &lt; 0.01), as well as grip strength (p &lt; 0.01 for both right and left hands). Quality of life results from the EQ-5D-5L [see figure part b)] indicated an overall reduction for the cachectic group (p = 0.047). Of the EQ-5D-5L subscales, mobility and ‘usual activities’ were significantly reduced (p = 0.02 and p &lt; 0.01 respectively), highlighting a significant change in the daily routine and ability of these patients. The FACIT-Fatigue questionnaire showed cachectic patients to be significantly more fatigued (p &lt; 0.01) [see figure part a)], whilst the FAACT demonstrated reduced physical wellbeing (p = 0.02) and greater issues with diet and appetite (p &lt; 0.01).

Conclusions

This is the first prevalence study of cardiac cachexia within Northern Ireland. The 15% prevalence rate shows that the syndrome is relatively common in the advanced heart failure population. Cardiac Cachexia has severe physical consequences, attributed to an individual’s weight loss in both fat and muscle tissue. Such changes may explain the subsequent decrease in mobility and the ability of these patients to conduct their ‘usual activities’. Increased fatigue, reduced physical wellbeing and issues with diet and appetite only intensify these dire physical effects. It is hoped that these results will highlight the impact of this syndrome and promote targeted interventions.

An in vivo screen of noncoding loci reveals that Daedalus is a gatekeeper of an Ikaros-dependent checkpoint during haematopoiesis

Haematopoiesis relies on tightly controlled gene expression patterns as development proceeds through a series of progenitors. While the regulation of hematopoietic development has been well studied, the role of noncoding elements in this critical process is a developing field. In particular, the discovery of new regulators of lymphopoiesis could have important implications for our understanding of the adaptive immune system and disease. Here we elucidate how a noncoding element is capable of regulating a broadly expressed transcription factor, Ikaros, in a lymphoid lineage-specific manner, such that it imbues Ikaros with the ability to specify the lymphoid lineage over alternate fates. Deletion of the Daedalus locus, which is proximal to Ikaros, led to a severe reduction in early lymphoid progenitors, exerting control over the earliest fate decisions during lymphoid lineage commitment. Daedalus locus deletion led to alterations in Ikaros isoform expression and a significant reduction in Ikaros protein. The Daedalus locus may function through direct DNA interaction as Hi-C analysis demonstrated an interaction between the two loci. Finally, we identify an Ikaros-regulated erythroid-lymphoid checkpoint that is governed by Daedalus in a lymphoid-lineage-specific manner. Daedalus appears to act as a gatekeeper of Ikaros's broad lineage-specifying functions, selectively stabilizing Ikaros activity in the lymphoid lineage and permitting diversion to the erythroid fate in its absence. These findings represent a key illustration of how a transcription factor with broad lineage expression must work in concert with noncoding elements to orchestrate hematopoietic lineage commitment.

Wapl repression by Pax5 promotes V gene recombination by Igh loop extrusion

Nuclear processes, such as V(D)J recombination, are orchestrated by the three-dimensional organization of chromosomes at multiple levels, including compartments1 and topologically associated domains (TADs)2,3 consisting of chromatin loops4. TADs are formed by chromatin-loop extrusion5-7, which depends on the loop-extrusion function of the ring-shaped cohesin complex8-12. Conversely, the cohesin-release factor Wapl13,14 restricts loop extension10,15. The generation of a diverse antibody repertoire, providing humoral immunity to pathogens, requires the participation of all V genes in V(D)J recombination16, which depends on contraction of the 2.8-Mb-long immunoglobulin heavy chain (Igh) locus by Pax517,18. However, how Pax5 controls Igh contraction in pro-B cells remains unknown. Here we demonstrate that locus contraction is caused by loop extrusion across the entire Igh locus. Notably, the expression of Wapl is repressed by Pax5 specifically in pro-B and pre-B cells, facilitating extended loop extrusion by increasing the residence time of cohesin on chromatin. Pax5 mediates the transcriptional repression of Wapl through a single Pax5-binding site by recruiting the polycomb repressive complex 2 to induce bivalent chromatin at the Wapl promoter. Reduced Wapl expression causes global alterations in the chromosome architecture, indicating that the potential to recombine all V genes entails structural changes of the entire genome in pro-B cells.

A226 CHILD AND PARENT PERCEPTIONS OF FAECAL MICROBIOTA TRANSPLANT (FMT): QUALITATIVE PERSPECTIVES FROM PARTICIPANTS IN A TRIAL OF FMT FOR PEDIATRIC ULCERATIVE COLITIS

Background

Fecal microbiota transplant (FMT) is being increasingly studied across a range of therapeutic indications, including ulcerative colitis (UC). Pediatric patients may have unique responses to microbiome-based therapeutics, given their younger age, fewer comorbidities, and greater susceptibility to medication-related side effects.

Aims

We recently conducted the first pilot RCT of FMT in Canada for the treatment of pediatric ulcerative colitis (PediFETCh Trial) and conducted qualitative interviews post-study of participants and their parents. This study aims to describe the experience and perceptions of children who received FMT, and their parents.

Methods

Patients enrolled in the PediFETCh Trial (ClinicalTrials.gov: NCT02487238) and their parents were invited to participate in face-to-face, semi-structured interviews. Interviews were audiotaped, transcribed, and analyzed using open coding (NVivo 12 Pro).

Results

8 patients and 8 parents were interviewed. Our data has been summarized into 4 domains and 11 composite themes (Table 1). Most patients and parents saw FMT as a natural treatment. Pre-treatment, patients were concerned with receiving “someone else’s poo” and physical discomfort, while parents were concerned with transmission of enteric infections or psychiatric diseases. Both felt their decision to pursue FMT was influenced by frustration with previous lack of response to medications and a fear of medication side effects. Post-treatment, most patients and families expressed no concerns over potential future side effects as a result of the FMT, and all patients reported feeling “completely normal”. Patients were split between preferring FMT or medication, with convenience of medication being an important factor, while others favored FMT for its perceived naturality and symptomatic improvements. For most families, natural therapies and diet played an important role in influencing their decision to pursue FMT; however, several parents reported that alternative healthcare practitioners did not support their desire to pursue FMT.

Conclusions

The study offers valuable insights into pediatric patients’ and parents’ experiences receiving FMT across several themes. Our results suggest a high rate of acceptance and interest in FMT research by pediatric patients and their parents. These findings suggest strategies to improve future delivery of FMT in clinical trials, and should support inclusion of children in FMT-based studies.

Funding Agencies

Hamilton Health Sciences New Investigator Fund (2015, Spring); Innovation Fund of the Alternative Funding Plan for the Academic Health Sciences Centres of Ontario (HAH-17-002)

A242 EXERCISE AND PHYSICAL ACTIVITY IN PEDIATRIC INFLAMMATORY BOWEL DISEASE: A SYSTEMATIC REVIEW AND RECOMMENDATIONS

Background

Inflammatory bowel disease (IBD) is a chronic life-long condition affecting 0.25% of the North American population. Childhood onset IBD is particularly aggressive, with disease often characterised by poor growth, severe unpredictable abdominal pain and frequent school absences. Treatment involves lifelong medications, which do not always resolve symptoms and carry increased cumulative risks of infections, malignancy, or other adverse effects. Exercise has been suggested as a method of ameliorating some of the symptoms associated with IBD. To date, few studies have investigated the role of exercise and physical activity in paediatric IBD patients.

Aims

We conducted a systematic review assessing the role of exercise and physical activity in paediatric IBD.

Methods

This Level III systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. An electronic database search of Pubmed, Google Scholar, and Cochrane used the search terms “(physical activity or exercise), (Inflammatory Bowel Disease), and (children or paediatric)”. Of the 1458 articles identified during the two rounds of review, only 21 articles met final inclusion criteria.

Results

Three main themes emerged from the review: 1) prescriptive exercise and physical activity ameliorated symptoms IBD and improved physical well-being, 2) patients who actively engage in exercise and physical activity show improved markers of inflammation and decreased future risk of disease, 3) exercise and physical activity improves the mental health and well-being of paediatric IBD patients. The results recommended 30–60 minutes, 6 times per week of mild to moderate aerobic exercise activity. It was noted that vigorous and high intensity exercise was well-tolerated by most IBD patients. Further, exercise prescription should be tailored to individual needs.

Conclusions

Exercise and physical activity improves mental and physical health and well-being of paediatric IBD patients, including decreasing the risk of future disease exacerbation in patients with mild to moderate disease activity. Clinicians and practitioners should consider actively prescribing exercise and physical activity to IBD patients as part of a standard treatment algorithm.

Funding Agencies

None

Swimming during COVID-19: Operational recommendations and considerations for South African swimming venues

Swimming is one of the most popular recreational activities in South Africa. Since the emergence of the Coronavirus disease 2019 (COVID-19), South Africa imposed one of the strictest lockdown measures to contain and control the spread of the virus. These measures included the closure of gyms, fitness centres and swimming pools across the country. However, as the restrictions begin to ease, it is important to consider how swimming facilities can reopen whilst simultaneously ensuring appropriate measures are in place to reduce COVID-19 infections. Outlined are recommendations and considerations for swimming facilities in South Africa. Currently there is no evidence to suggest that COVID-19 transmission to humans is possible through water, making swimming one of the safer options for physical activity indoors. However, participation is still not without risk and compliance with government mandates and public health officials take precedent over the recommendations outlined in this article.

TECRA® Unique™ Test for Rapid Detection of Salmonella in Food: Collaborative Study

The TECRA® Unique™ Salmonella test uses the principle of immunoenrichment to allow rapid detection of Salmonellae in food. A collaborative study was conducted to compare the TECRA Salmonella Unique test with the reference culture method given in the U.S. Food and Drug Administration's Bacteriological Analytical Manual. Three food types (milk powder, pepper, and soy flour) were analyzed in Australia and 2 food types (milk chocolate and dried egg) were analyzed in the United States. Forty-one collaborators participated in the study. For each of the 5 foods at each of the 3 levels, a comparison showed no significant differences (p ≥ 0.05) in the proportion of positive test samples for Unique and that for the reference method using the Chi-square test for independence with continuity correction.

Towards a rapid assessment protocol for identifying pit lakes worthy of restoration

Before the introduction of reclamation legislation in South Africa, final cut lakes in mining areas were left without any restoration while the final excavation was not back filled. Characteristics of these lacustrine water bodies vary considerably, but they are often linear in shape, large (1-30 ha), deep (2-30 m) and have poorly developed littoral zones. With water tables often near the surface; a variety of vascular hydrophytes can colonize these bodies, thus establishing emerging wetland type ecosystems. These, man-made aquatic structures that are (unintentionally) created potentially offers some realistic and inexpensive mitigation options for some of the negative impacts associated with mining, i.e. these water bodies can become useful by yielding potentially valuable services. However, no method currently exists to compare and rank these water bodies according ecological integrity and the expected monetary value to be derived from them in order to select sites for restoration. To answer this need, we applied an index to determine the ability of these water bodies to provide useful services in their current state. The index was then used to derive estimates of the monetary value of potential services in order to allow comparison with the cost of restoring the water body in question or to compare with other pit lakes. We present a South African case study to illustrate the method. As far as could be established, this is the first attempt towards creating a rapid assessment tool as standardised way of comparing pit lakes that allows for the ranking and identification of those pit lakes worthy of restoration.

River catchment responses to anthropogenic acidification in relationship with sewage effluent: An ecotoxicology screening application

Rising environmental pressures on water resources and resource quality associated with urbanisation, industrialisation, mining and agriculture are a global concern. In the current study the upper Olifants River catchment as case study was used, to show that acid mine drainage (AMD) and acid precipitation were the two most important drivers of possible acidification during a four-year study period. Over the study period 59% of the precipitation sampled was classified as acidic with a pH value below 5.6. Traces of acidification in the river system using aquatic organisms at different trophic levels were only evident in areas of AMD point sources. Data gathered from the ecotoxicology screening tools, revealed that discharge of untreated and partially treated domestic sewage from municipal sewage treatment works and informal housing partially mitigate any traces of acidification by AMD and acid precipitation in the main stem of the upper Olifants River. The outcome of the study using phytoplankton and macroinvertebrates as indicator organisms revealed that the high loads of sewage effluent might have played a major role in the neutralization of acidic surface water conditions caused by AMD and acid precipitation. Although previous multi-stage and microcosm studies confirmed the decrease in acidity and metals concentrations by municipal wastewater, the current study is the first to provide supportive evidence of this co-attenuation on catchment scale. These findings are important for integrated water resource management on catchment level, especially in river systems with a complex mixture of pollutants.

Mixed drink increased carbohydrate oxidation but not performance during a 40 km time trial

Background: The present study aimed to determine whether consuming a glucose polymer (GP) and fructose would result in increased carbohydrate oxidation rates and improve 40 km time trial performance compared with an isocaloric GP-only drink.Methods: Eight well-trained male competitive cyclists (VO2max 62.7 ± 9.4 ml/kg/min, power output 5.1 ± 0.6 Watts/kg) participated in three visits consisting of a peak power output (Wmax) and VO2 max test and two separate visits of a 105 minute steady state ride (at 65% Wmax), followed by a 40 km time trial. Participants received 1.2 g/min of either a GP or mixed drink every 15 min.Results: No differences were found in the 40 km performance between GP (69:14 min ± 4.12, mean ± SD) and the mixed drink (66:58 min ± 4.51, mean ± SD) trials (p = 0.289). There were no differences in blood glucose or lactate between the trials. No differences in total oxidation were found in either carbohydrate or fat oxidation rates; however, exogenous carbohydrate oxidation was significantly different between the GP drink trials at t=90 min (GP: 0.96 ± 0.36 g/min; mixed drink: 1.53 ± 0.48 g/min; p = 0.041, mean ± SD).Conclusion: The present study found no improvement in 40 km time trial time between an isocaloric GP-only or a GP and fructose drink, and no differences in any of the measured variables other than exogenous carbohydrate oxidation at 90 minutes during the pre-time trial steady state ride.

Impact of white-tailed deer on the spread of Borrelia burgdorferi

There is a public perception that the white-tailed deer Odocoileus virginianus (Artiodactyla: Cervidae) is the main reservoir supporting the maintenance and spread of the causative agent of Lyme disease, Borrelia burgdorferi. This study examines the pathogen prevalence rate of Borrelia in adult Ixodes scapularis (Ixodida: Ixodidae), the black-legged tick, collected from white-tailed deer and compares it with pathogen prevalence rates in adult ticks gathered by dragging vegetation in two contiguous counties west of the Hudson Valley in upstate New York. In both Broome and Chenango Counties, attached and unattached ticks harvested from white-tailed deer had significantly lower prevalences of B. burgdorferi than those collected from vegetation. No attached ticks on deer (n = 148) in either county, and only 2.4 and 7.3% of unattached ticks (n = 389) in Broome and Chenango Counties, respectively, were harbouring the pathogen. This contrasts with the finding that 40.8% of ticks in Broome County and 46.8% of ticks in Chenango County collected from vegetation harboured the pathogen. These data suggest that a mechanism in white-tailed deer may aid in clearing the pathogen from attached deer ticks, although white-tailed deer do contribute to the spatial distribution of deer tick populations and also serve as deadend host breeding sites for ticks.

Abstract P3-13-20: Use of a 3-D bioabsorbable tissue marker in 61 patients over two years

Background: Breast conservation surgery (BCS) may preserve the breast but many women have less than optimal cosmetic outcomes. Increasingly, this has been addressed by the use of oncoplastic reconstruction.Now, targeting radiation treatment for boost or partial breast irradiation (PBI) using the seroma has become more difficult due to the adjacent tissue rearrangement and resultant “benign” seromas. Since the radiation dose generated increases by the third power of the radius (r3), there is a need to accurately focus radiation therapy to avoid chronic radiation side effects.We have used a 3-dimensional bioabsorbable tissue marker to accurately target the tumor bed while excluding inadvertent seromas caused by oncoplastic procedures. We report on tissue marker implantation on 61 consecutive breast conservation patients in regards to targeting, impact on cosmesis, imaging followup, ease of re-excision, as well as side effects and patient satisfaction.

METHODS: Consecutive lumpectomy patients who were candidates for targeted radiation therapy were considered for implantation with the 3-D bioabsorbable marker from May 2014 to June 2016. The tissue marker has a fixed array of 6 titanium clips and was sutured to the site of the excised breast cancer during lumpectomy.The framework of the implant resorbs slowly over time, while the clips remain permanently. All patients had oncoplastic reconstruction with total implant coverage. The marker was utilized for boost or partial breast irradiation (PBI) planning or treatment targeting. Data includes patient demographics, breast size, tumor characteristics, surgical and radiotherapy techniques, follow-up imaging, cosmesis and patient satisfaction.

Results:Data on 61 patients with median follow-up 12.7 months was analyzed (range 1.5–25.5). Median age was 62.4 years (range 33-74), 5 of women were postmenopausal and 15% had comorbidities. Cancer histology was in-situ (13%), invasive ductal (84%), invasive lobular (3%) of sizes T0 (13%), T1 (59%), T2 (25%), T3-4 (3%). Laterality and tumor location within the breast were typical. Re-excisions occurred in 11% of patients. No infections occurred in the postoperative period. One infection occurred with chemotherapy and another with repeated aspirations of oncoplastic area.No device was removed for infection, misplacement or patient-generated concerns. No cancer recurrences have been reported. Size of device used reflected size of the tumor; 2X2cm (44%), 2X3cm (34%) and 3X3cm (20%). The device was utilized by radiation oncologists for boost or PBI planning and treatment. Data on ease of setup and boost planning is being collected. Mammography at one year demonstrated marker clips coalescing as the bioabsorbable device dissolves. Evaluation of cosmetic appearance has shown good to excellent cosmesis as judged separately by both physicians and patients (92% and 94%).

Conclusions: Initial experience with 61 patients implanted with a novel 3-D absorbable device prospectively followed for an average of 12 months can be used in an array of breast cancer patients without device specific morbidity. Good to excellent cosmesis may be related to the addition of volume to the lumpectomy bed not seen with rearrangement of existing tissues.

Citation Format: Kaufman CS, Hall W, Behrndt V, Wolgamot G, Hill L, Zacharias K, Rogers A, Nix S, Schnell N. Use of a 3-D bioabsorbable tissue marker in 61 patients over two years [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-13-20.

Abstract P3-07-57: Development of a 6-gene qPCR RUO-validated assay as a predictive biomarker for response of vantictumab (OMP-18R5; anti-frizzled) in HER2- breast cancer patients

Background: We have developed a monoclonal antibody, vantictumab that blocks canonical WNT/β-catenin signaling through binding of five FZD receptors (1, 2, 5, 7, 8). This antibody inhibits the growth of several tumor types, including breast. Vantictumab reduces tumor-initiating cell frequency and exhibits synergistic activity with standard-of-care (SOC) agents (Gurney et al, 2012). To target breast cancer patients most likely to respond to vantictumab, we undertook a predictive biomarker study.

Methods: We have identified a 6-gene Wnt pathway-related signature, FBXW2, CCND2, RHOU, CTBP2, WIF1, and DKK1, based on microarray gene expression data from 8 breast cancer patient derived xenograft (PDX) models with established in vivo response to vantictumab plus SOC. This signature successfully predicted the response of 8 additional and independent PDX breast tumors. We further developed a qPCR Research Use Only (RUO) assay for the 6 genes to be used on FFPE human breast tumor samples. Multiple assays targeting different regions spanning each mRNA transcript were tested and selected based on PCR efficiency, specificity and sensitivity. We compared assay sensitivity under different cDNA synthesis and pre-amplification conditions: random vs. gene-specific priming, number of pre-amplification cycles, pre-amplification reaction volumes, and cDNA synthesis kits. A repeatability study was performed to test assay performance. The pre-amplification and PCR were repeated over three separate days and across two independent labs.

Results: Our results showed that cDNA synthesis by gene-specific priming followed by 18 cycles of pre-amplification performed the best and the assay is robust with minimal starting FFPE RNA input. The results of the repeatability study were consistent among the different days and the different labs (&lt;5% CV). Using the 6-gene qPCR RUO assay, the signature score from the microarray data was further refined using 12 PDX HER2- breast tumors with known in vivo response to vantictumab with SOC. The prevalence of the 6-gene signature was established using ∼100 HER2- breast cancer samples.

Conclusions: A robust 6-gene RUO-validated assay was developed as a predictive biomarker for vantictumab in HER2- breast cancer. The assay is currently being evaluated in a Phase 1b study of vantictumab with paclitaxel in HER2- breast cancer.

Citation Format: Zhang C, O'Young G, Wikstrom K, Davison T, Yeung P, Cattaruzza F, Yen W-C, Hoey T, Lewicki J, Rachmann R, Kerr P, Hill L, Eason R, McErlean S, Liu Y, Kapoun AM. Development of a 6-gene qPCR RUO-validated assay as a predictive biomarker for response of vantictumab (OMP-18R5; anti-frizzled) in HER2- breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-57.

Randomized controlled trial comparing impact on platelet reactivity of twice-daily with once-daily aspirin in people with Type 2 diabetes

AIMS

Reduced aspirin efficacy has been demonstrated in people with Type 2 diabetes. Because increased platelet reactivity and/or turnover are postulated mechanisms, we examined whether higher and/or more frequent aspirin dosing might reduce platelet reactivity more effectively.

METHODS

Participants with Type 2 diabetes (n = 24) but without known cardiovascular disease were randomized in a three-way crossover design to 2-week treatment periods with aspirin 100 mg once daily, 200 mg once daily or 100 mg twice daily. The primary outcome was platelet reactivity, assessed using the VerifyNow(™) ASA method. Relationships between platelet reactivity and aspirin dosing were examined using generalized linear mixed models with random subject effects.

RESULTS

Platelet reactivity decreased from baseline with all doses of aspirin. Modelled platelet reactivity was more effectively reduced with aspirin 100 mg twice daily vs. 100 mg once daily, but not vs. 200 mg once daily. Aspirin 200 mg once daily did not differ from 100 mg once daily. Aspirin 100 mg twice daily was also more effective than once daily as measured by collagen/epinephrine-stimulated platelet aggregation and urinary thromboxane levels, with a similar trend measured by serum thromboxane levels. No episodes of bleeding occurred.

CONCLUSIONS

In Type 2 diabetes, aspirin 100 mg twice daily reduced platelet reactivity more effectively than 100 mg once daily, and numerically more than 200 mg once daily. Clinical outcome trials evaluating primary cardiovascular disease prevention with aspirin in Type 2 diabetes may need to consider using a more frequent dosing schedule.

Spatial Regulation of V-(D)J Recombination at Antigen Receptor Loci

Lymphocytes express a diverse repertoire of antigen receptors, which are able to recognize a large variety of foreign pathogens. Functional antigen receptor genes are assembled by V(D)J recombination in immature B cells (Igh and Igk) and T cells (Tcr b and Tcra/d). V(D)J recombination takes place in the 3' proximal domain containing the D, J, and C gene segments, whereas 31 (Tcrb) to 200 (Igh) V genes are spread over a large region of 0.67 (Tcrb) to 3 (Igk) megabase pairs. The spatial regulation of V(D)J recombination has been best studied for the Igh locus, which undergoes reversible contraction by long-range looping in pro-B cells. This large-scale contraction brings distantly located VH genes into close proximity of the DJH-rearranged gene segment, which facilitates VH-DJH recombination. The B-cell-specific Pax5, ubiquitous YY1, and architectural CTCF/cohesin proteins regulate Igh locus contraction in pro-B cells by binding to multiple sites in the VH gene cluster. These regulators also control the pro-B-cell-specific activity of the distally located PAIR elements, which may be involved in the regulation of VH-DJH recombination by promoting locus contraction. Moreover, the large VH gene cluster of the Igh locus undergoes flexible long-range looping, which guarantees similar participation of all VH genes in VH-DJH recombination to generate a diverse antibody repertoire. Importantly, long-range looping is a more general regulatory principle, as other antigen receptor loci also undergo reversible contraction at the developmental stage, where they engage in V-(D)J recombination.