Valproic acid disables the Nrf2 anti-oxidant response in acute myeloid leukaemia cells enhancing reactive oxygen species-mediated killing

BACKGROUND

We previously demonstrated the in vitro killing of AML cells by the combination of the lipid-lowering agent bezafibrate (BEZ) and the contraceptive hormone medroxyprogesterone acetate (MPA). A phase II trial demonstrated in vivo safety and efficacy of BEZ and MPA (BaP) in elderly, relapsed/refractory AML and high-risk myelodysplastic syndrome (MDS) patients. However, we observed dose-limiting toxicities in a second trial that attempted to improve outcomes via escalation of BaP doses. Thus we sought to identify a third repurposed drug that potentiates activity of low dose BaP (BaP 0.1 mM).

METHODS AND RESULTS

We demonstrate that addition of a commonly used anti-epileptic, valproic acid (VAL) to low dose BaP (BaP 0.1 mM)(VBaP) enhanced killing of AML cell lines/primary AML cells to levels similar to high dose BaP (BaP 0.5 mM). Similarly, addition of VAL to BaP 0.1 mM enhanced reactive oxygen species (ROS), lipid peroxidation and inhibition of de novo fatty acid synthesis. Overexpression of Nrf2 in K562 and KG1a completely inhibited ROS production and rescued cells from VAL/BaP 0.1 mM/VBaP killing.

CONCLUSIONS

Given the good safety data of low-dose BaP in elderly/relapsed/refractory AML patients, and that VAL alone is well-tolerated, we propose VBaP as a novel therapeutic combination for AML.

805 Eluting Electrodes for Hearing Preservation – the Future of Cochlear Implantation?

Introduction

Cochlear implants (CIs) utilising eluting electrodes are a relatively new phenomenon. CI surgery can lead to a variety of complications, namely electrode insertion trauma. This affects CI function leading to a loss of residual hearing. To minimise this, electrodes eluting anti-inflammatory or growth-promoting agents can be used to protect and enhance residual hearing through the sustained release of an agent. Eluting agents include glucocorticoids, steroids, growth factors and neurotrophins.

Method

Systematic review and narrative synthesis.

Databases

searched

Results

Searches identified 66 abstracts and 37 full texts. Of these, 15 studies met the inclusion criteria, reporting outcomes in 469 animals and 24 humans, with at least 233 implants. Eluting electrodes included dexamethasone (n = 13), growth factor (n = 1) and neurotrophins (n = 1). Audiological outcomes improved across all studies following cochlear implantation with an eluting electrode to a greater extent when compared to a standard electrode. Outcomes improved significantly when a higher concentration of dexamethasone was used.

Conclusions

Audiological outcomes with eluting electrodes following cochlear implantation are generally superior to the omission of medication following cochlear implantation. An electrode elution enables a sustained, localised release of anti-inflammatory or anti-apoptotic agents, therefore reducing the advent of fibrosis, scarring and subsequent impedance.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Effects of passive smoking on outcome in pregnancy

BACKGROUND

Adverse health effects of exposure to environmental tobacco smoke (ETS) among non-smokers have been studied occasionally in developing countries.

AIMS

To study the effects of exposure to ETS on outcome in pregnancy

SETTINGS AND DESIGN

A cross-sectional study at a secondary level teaching hospital Material and Methods: Consecutive 576 non-smoking women delivering a singleton live baby were studied. A pre-designed structured questionnaire was used to record the details of exposure to ETS at home. The maternal and foetal variables were compared among those who were exposed to ETS vis-à-vis not exposed. Unpaired Student t-test was used for the comparison of continuous variables and Fisher's Exact test was used for categorical variables. Multiple logistic regression analysis was performed after including all variables found to have significant differences on univariate analysis.

RESULTS

Of the 576 women studied 141 (24%) were exposed to ETS. In the mothers exposed to ETS, there was a significantly higher incidence of pre-term birth (24.1% vs. 16.1%; P = 0.027) and small-for-gestation babies (31.9% vs.17.2%; p<0.001) as compared to unexposed mothers. The mean birth weight of the babies born to the mothers exposed to ETS was 138 g less than that of babies in the unexposed group (2632 -/+577 g vs. 2770 -/+562 g respectively, p = 0.014). The multiple logistic regression analyses showed that ETS exposure during pregnancy was significantly associated with a higher risk of small-for-gestation babies (OR 2.10; 95% CI: 1.27-3.48).

CONCLUSION

Exposure to ETS during pregnancy is associated with higher risk of having a small-for-gestation baby.

Microbiological studies in mid-trimester abortion with Emcredil versus normal saline

In 40 mid-trimester abortion seekers, in whom abortion was induced by extra-amniotic normal saline or Emcredil, microbiological studies were carried out before induction and at 24 hours. It was observed that there was no difference in the isolation of organisms from vagina and cervix of these subjects between 0 hours and 24 hours. Thus, this study shows that leaving the catheter in the extra-amniotic space until it is expelled spontaneously does not increase the risk of ascending infection. At the same time, leaving the catheter in-situ until it is expelled spontaneously reduces the induction-abortion interval appreciably.