Positive reinforcement targeting abstinence in substance misuse (PRAISe): Study protocol for a Cluster RCT & process evaluation of contingency management

There are approximately 256,000 heroin and other opiate users in England of whom 155,000 are in treatment for heroin (or opiate) addiction. The majority of people in treatment receive opiate substitution treatment (OST) (methadone and buprenorphine). However, OST suffers from high attrition and persistent heroin use even whilst in treatment. Contingency management (CM) is a psychological intervention based on the principles of operant conditioning. It is delivered as an adjunct to existing evidence based treatments to amplify patient benefit and involves the systematic application of positive reinforcement (financial or material incentives) to promote behaviours consistent with treatment goals. With an international evidence base for CM, NICE recommended that CM be implemented in UK drug treatment settings alongside OST to target attendance and the reduction of illicit drug use. While there was a growing evidence base for CM, there had been no examination of its delivery in UK NHS addiction services. The PRAISe trial evaluates the feasibility, acceptability, clinical and cost effectiveness of CM in UK addiction services. It is a cluster randomised controlled effectiveness trial of CM (praise and financial incentives) targeted at either abstinence from opiates or attendance at treatment sessions versus no CM among individuals receiving OST. The trial includes an economic evaluation which explores the relative costs and cost effectiveness of the two CM intervention strategies compared to TAU and an embedded process evaluation to identify contextual factors and causal mechanisms associated with variations in outcome. This study will inform UK drug treatment policy and practice. Trial registration ISRCTN 01591254.

High-level production and purification in a functional state of an extrasynaptic gamma-aminobutyric acid type A receptor containing α4β3δ subunits

The inhibitory γ-aminobutyric acid type A receptors are implicated in numerous physiological processes, including cognition and inhibition of neurotransmission, rendering them important molecular targets for many classes of drugs. Functionally, the entire GABAAR family of receptors can be subdivided into phasic, fast acting synaptic receptors, composed of α-, β- and γ-subunits, and tonic extrasynaptic receptors, many of which contain the δ-subunit in addition to α- and β-subunits. Whereas the subunit arrangement of the former group is agreed upon, that of the αβδ GABAARs remains unresolved by electrophysiological and pharmacological research. To resolve such issues will require biophysical techniques that demand quantities of receptor that have been previously unavailable. Therefore, we have engineered a stable cell line with tetracycline inducible expression of human α4-, β3- and N-terminally Flag-tagged δ-subunits. This cell line achieved a specific activity between 15 and 20 pmol [3H]muscimol sites/mg of membrane protein, making it possible to obtain 1 nmole of purified α4β3δ GABAAR from sixty 15-cm culture dishes. When induced, these cells exhibited agonist-induced currents with characteristics comparable to those previously reported for this receptor and a pharmacology that included strong modulation by etomidate and the δ-subunit-specific ligand, DS2. Immunoaffinity purification and reconstitution in CHAPS/asolectin micelles resulted in the retention of equilibrium allosteric interactions between the separate agonist, anesthetic and DS2 sites. Moreover, all three subunits retained glycosylation. The establishment of this well-characterized cell line will allow molecular level studies of tonic receptors to be undertaken.

The association between biopsychosocial factors and disability in a national health survey in South Africa

The association between psychosocial factors and disability is less clear. This study investigated the biological and psychosocial (employment and psychological distress) factors associated with level of disability in an adult sample in South Africa. Data were analysed from a cross-sectional survey among adults aged 18-64 (n = 4974). Multiple linear regression was used to investigate the associations of the selected variables with disability. The mean percentage score on the WHODAS scale of disability was 5.31% (95% CI: 4.74-5.88). Age (p < 0.001) and race (p = 0.0002) were significantly associated with disability, and history of stroke (β = 7.19, 95% CI: 3.19-11.20) and heart-related conditions (β = 2.08, 95% CI: [0.23-3.93) showed positive associations. Of the psychosocial variables, psychological distress (β = 10.49 [8.63-12.35]) showed a strong positive association while employment (-1.62 [-2.36 to -0.88]) showed a negative association with disability. The association between demographic factors, medical conditions and increased disability confirms the findings in the literature. The finding that psychological distress is associated with increased disability has not been frequently reported. This study highlights specific psychosocial targets that may be usefully addressed by health policies and interventions in order to improve disability management.

Synthesis and pharmacological evaluation of neurosteroid photoaffinity ligands

Neuroactive steroids are potent positive allosteric modulators of GABA_A receptors (GABA_AR), but the locations of their GABA_AR binding sites remain poorly defined. To discover these sites, we synthesized two photoreactive analogs of alphaxalone, an anesthetic neurosteroid targeting GABA_AR, 11β-(4-azido-2,3,5,6-tetrafluorobenzoyloxy)allopregnanolone, (F4N3Bzoxy-AP) and 11-aziallopregnanolone (11-AziAP). Both photoprobes acted with equal or higher potency than alphaxalone as general anesthetics and potentiators of GABA_AR responses, left-shifting the GABA concentration - response curve for human α1β3γ2 GABA_ARs expressed in Xenopus oocytes, and enhancing [³H]muscimol binding to α1β3γ2 GABA_ARs expressed in HEK293 cells. With EC₅₀ of 110 nM, 11-AziAP is one the most potent general anesthetics reported. [³H]F4N3Bzoxy-AP and [³H]11-AziAP, at anesthetic concentrations, photoincorporated into α- and β-subunits of purified α1β3γ2 GABA_ARs, but labeling at the subunit level was not inhibited by alphaxalone (30 μM). The enhancement of photolabeling by ³H-azietomidate and ³H-mTFD-MPAB in the presence of either of the two steroid photoprobes indicates the neurosteroid binding site is different from, but allosterically related to, the etomidate and barbiturate sites. Our observations are consistent with two hypotheses. First, F4N3Bzoxy-AP and 11-aziAP bind to a high affinity site in such a pose that the 11-photoactivatable moiety, that is rigidly attached to the steroid backbone, points away from the protein. Second, F4N3Bzoxy-AP, 11-aziAP and other steroid anesthetics, which are present at very high concentration at the lipid-protein interface due to their high lipophilicity, act via low affinity sites, as proposed by Akk et al. (Psychoneuroendocrinology2009, 34S1, S59-S66).

Contrasting actions of a convulsant barbiturate and its anticonvulsant enantiomer on the α1 β3 γ2L GABAA receptor account for their in vivo effects

KEY POINTS

Most barbiturates are anaesthetics but unexpectedly a few are convulsants whose mechanism of action is poorly understood. We synthesized and characterized a novel pair of chiral barbiturates that are capable of photolabelling their binding sites on GABAA receptors. In mice the S-enantiomer is a convulsant, but the R-enantiomer is an anticonvulsant. The convulsant S-enantiomer binds solely at an inhibitory site. It is both an open state inhibitor and a resting state inhibitor. Its action is pH independent, suggesting the pyrimidine ring plays little part in binding. The inhibitory site is not enantioselective because the R-enantiomer inhibits with equal affinity. In contrast, only the anticonvulsant R-enantiomer binds to the enhancing site on open channels, causing them to stay open longer. The enhancing site is enantioselective. The in vivo actions of the convulsant S-enantiomer are accounted for by its interactions with GABAA receptors.

ABSTRACT

Most barbiturates are anaesthetics but a few unexpectedly are convulsants. We recently located the anaesthetic sites on GABAA receptors (GABAA Rs) by photolabelling with an anaesthetic barbiturate. To apply the same strategy to locate the convulsant sites requires the creation and mechanistic characterization of a suitable agent. We synthesized enantiomers of a novel, photoactivable barbiturate, 1-methyl-5-propyly-5-(m-trifluoromethyldiazirinyl) phenyl barbituric acid (mTFD-MPPB). In mice, S-mTFD-MPPB acted as a convulsant, whereas R-mTFD-MPPB acted as an anticonvulsant. Using patch clamp electrophysiology and fast solution exchange on recombinant human α1 β3 γ2L GABAA Rs expressed in HEK cells, we found that S-mTFD-MPPB inhibited GABA-induced currents, whereas R-mTFD-MPPB enhanced them. S-mTFD-MPPB caused inhibition by binding to either of two inhibitory sites on open channels with bimolecular kinetics. It also inhibited closed, resting state receptors at similar concentrations, decreasing the channel opening rate and shifting the GABA concentration-response curve to the right. R-mTFD-MPPB, like most anaesthetics, enhanced receptor gating by rapidly binding to allosteric sites on open channels, initiating a rate-limiting conformation change to stabilized open channel states. These states had slower closing rates, thus shifting the GABA concentration-response curve to the left. Under conditions when most GABAA Rs were open, an inhibitory action of R-mTFD-MPPB was revealed that had a similar IC50 to that of S-mTFD-MPPB. Thus, the inhibitory sites are not enantioselective, and the convulsant action of S-mTFD-MPPB results from its negligible affinity for the enhancing, anaesthetic sites. Interactions with these two classes of barbiturate binding sites on GABAA Rs underlie the enantiomers' different pharmacological activities in mice.

Kv3.3 Channels Bind Hax-1 and Arp2/3 to Assemble a Stable Local Actin Network that Regulates Channel Gating

Mutations in the Kv3.3 potassium channel (KCNC3) cause cerebellar neurodegeneration and impair auditory processing. The cytoplasmic C terminus of Kv3.3 contains a proline-rich domain conserved in proteins that activate actin nucleation through Arp2/3. We found that Kv3.3 recruits Arp2/3 to the plasma membrane, resulting in formation of a relatively stable cortical actin filament network resistant to cytochalasin D that inhibits fast barbed end actin assembly. These Kv3.3-associated actin structures are required to prevent very rapid N-type channel inactivation during short depolarizations of the plasma membrane. The effects of Kv3.3 on the actin cytoskeleton are mediated by the binding of the cytoplasmic C terminus of Kv3.3 to Hax-1, an anti-apoptotic protein that regulates actin nucleation through Arp2/3. A human Kv3.3 mutation within a conserved proline-rich domain produces channels that bind Hax-1 but are impaired in recruiting Arp2/3 to the plasma membrane, resulting in growth cones with deficient actin veils in stem cell-derived neurons.

ID: 74: A RETROSPECTIVE STUDY OF CORONARY ARTERY DISEASE IN PATIENTS WITH BODY MASS INDEX ≥30

Introduction

Coronary Artery Disease (CAD) is a major cause of morbidity and mortality worldwide, and although mortality is decreasing, prevalence of CAD is increasing. A number of modifiable risk factors (smoking) and non-modifiable risk factors (gender, age) have well established association with CAD, whereas other potential risk factors (such as obesity) are less well established. In this study, we evaluated the obesity as a single risk factor for CAD and evaluated the synergistic effect of obesity with the other risk factors.

Method

A retrospective study of 7,567 patients admitted to hospital for chest pain from 2005–2014 and underwent cardiac catheterization. Patients were divided into two groups: obese and normal with body mass index (BMI) calculated as ≥30 kg/m2 and ≤25, respectively. Patients with BMIs between 26 and 29 were excluded. We assessed the modifiable and non-modifiable risk factors in obese patients and the degree of CAD with coronary angiography as obstructive CAD (left main stenosis of ≥50% or any stenosis of ≥70%), non-obstructive CAD (≥1 stenosis ≥20% but no stenosis ≥70%) and normal coronaries.

Results

Of the 7,567 patients who underwent cardiac catheterization, 414 (5.5%) had a BMI ≥30. Of 414 obese patients, 332 (80%) had evidence of CAD. Obese patients displayed evidence of CAD at the age of 57 versus 63.3 in non-obese patients (p<0.001).

Of the 332 patients with CAD and obesity, 55.4% had obstructive CAD versus 44.6% with non-obstructive CAD. In obese patients with CAD, Male gender and history of smoking were major risk factors for development of obstructive CAD (p=0.001 and 0.01, respectively) while dyslipidemia was a major risk factor for non-obstructive CAD (p 0.01). Additionally, obese patients with more than one risk factor; developed obstructive CAD compared to non-obstructive CAD (p=0.003). Approximately 40% presented with STEMI, 30% with NSTEMI and 30% had stable angina as a primary diagnosis.

Of the 332 obese patients with CAD, 24% received medical treatment, 58% underwent percutaneous coronary intervention (PCI) and 18% obtained coronary artery bypass grafting (CABG).

In a gender comparison, average age of CAD in obese males were 55 years of age compared to 59 in females (p <0.001). Approximately 67% of males underwent PCI (OR: 2.4, 95% CI: 1.5–3.6, p<0.001) and 24% obtained CABG (OR: 3, 95% CI: 1.6–5.6, p<0.001), whereas in obese females 43% received medical therapy (OR: 9, 95% CI: 5–17, p<0.001).

Conclusion

Having a BMI ≥30 appears to correlate as a risk factor for early development of CAD. Severity of CAD in obese patients is depicted on non-modifiable and modifiable risk factors such as the male gender and smoking or greater than one risk factor, respectively. Early lifestyle modification and education may provide benefit in striving to aid decreasing incidents of CAD and possibly lowering cardiovascular events.

Biological and psychosocial risk factors for psychotic major depression

AIMS

Few studies have investigated risk factors for psychotic major depression (PMD). We aimed to investigate the biological and psychosocial risk factors associated with PMD compared with other psychotic disorders.

METHODS

Based on the aetiology and ethnicity in schizophrenia and other psychoses (ÆSOP) study, we used a case-control study to identify and recruit, at baseline and 10-year follow-up, all first episode cases of psychosis, presenting for the first time to specialist mental health services in defined catchment areas in the UK. Population-based controls were recruited from the same areas. Data were collected on: sociodemographics; social isolation; childhood adversity; life events; minor physical anomalies; and neurological soft signs.

RESULTS

Living alone (aOR = 2.26, CI = 1.21-4.23), basic level qualification (aOR = 2.89, CI = 1.08-7.74), being unemployed (aOR = 2.12, CI = 1.13-3.96), having contact with friends less than monthly (aOR = 4.24, CI = 1.62-11.14), having no close confidants (aOR = 4.71, CI = 2.08-10.68), having experienced childhood adversity (aOR = 2.57, CI = 1.02-6.44), family history of mental illness (aOR = 10.68, CI = 5.06-22.52), family history of psychosis (aOR = 12.85, CI = 5.24-31.51), and having more neurological soft signs (aOR = 1.15, CI = 1.07-1.24) were all associated with a follow-up diagnosis of PMD and schizophrenia. Few variables associated with PMD were also associated with a diagnosis of bipolar disorder. Minor physical anomalies were associated with a follow-up diagnosis of schizophrenia and bipolar disorder, but not PMD.

CONCLUSIONS

Risk factors associated with PMD appear to overlap with those for schizophrenia, but less so for bipolar disorder. Future work on the differential aetiology of PMD, from other psychoses is needed to find the 'specifier' between PMD and other psychoses. Future research on aetiology in PMD, and perhaps other psychoses, should account for diagnostic change.

Positive and Negative Allosteric Modulation of an α1β3γ2 γ-Aminobutyric Acid Type A (GABAA) Receptor by Binding to a Site in the Transmembrane Domain at the γ+-β- Interface

In the process of developing safer general anesthetics, isomers of anesthetic ethers and barbiturates have been discovered that act as convulsants and inhibitors of γ-aminobutyric acid type A receptors (GABAARs) rather than potentiators. It is unknown whether these convulsants act as negative allosteric modulators by binding to the intersubunit anesthetic-binding sites in the GABAAR transmembrane domain (Chiara, D. C., Jayakar, S. S., Zhou, X., Zhang, X., Savechenkov, P. Y., Bruzik, K. S., Miller, K. W., and Cohen, J. B. (2013) J. Biol. Chem. 288, 19343-19357) or to known convulsant sites in the ion channel or extracellular domains. Here, we show that S-1-methyl-5-propyl-5-(m-trifluoromethyl-diazirynylphenyl) barbituric acid (S-mTFD-MPPB), a photoreactive analog of the convulsant barbiturate S-MPPB, inhibits α1β3γ2 but potentiates α1β3 GABAAR responses. In the α1β3γ2 GABAAR, S-mTFD-MPPB binds in the transmembrane domain with high affinity to the γ(+)-β(-) subunit interface site with negative energetic coupling to GABA binding in the extracellular domain at the β(+)-α(-) subunit interfaces. GABA inhibits S-[(3)H]mTFD-MPPB photolabeling of γ2Ser-280 (γM2-15') in this site. In contrast, within the same site GABA enhances photolabeling of β3Met-227 in βM1 by an anesthetic barbiturate, R-[(3)H]methyl-5-allyl-5-(m-trifluoromethyl-diazirynylphenyl)barbituric acid (mTFD-MPAB), which differs from S-mTFD-MPPB in structure only by chirality and two hydrogens (propyl versus allyl). S-mTFD-MPPB and R-mTFD-MPAB are predicted to bind in different orientations at the γ(+)-β(-) site, based upon the distance in GABAAR homology models between γ2Ser-280 and β3Met-227. These results provide an explanation for S-mTFD-MPPB inhibition of α1β3γ2 GABAAR function and provide a first demonstration that an intersubunit-binding site in the GABAAR transmembrane domain binds negative and positive allosteric modulators.

Diagnostic Disparity in Solitary Cysticercosis of the Forearm in a Child

Solitary cysticercosis of muscle is a rare disease causing diagnostic dilemma. Cysticercosis commonly affects the central nervous system and other tissues by dissemination imposing a serious health problem. We report this rare presentation of solitary cysticercosis of flexor digitorum superficialis in a five year old otherwise healthy child. The fine needle aspiration cytology and histopathological diagnosis were inconclusive but ultrasonography of the muscle clinched the diagnosis.

Haplosufficient genomic androgen receptor signaling is adequate to protect female mice from induction of polycystic ovary syndrome features by prenatal hyperandrogenization

Polycystic ovary syndrome (PCOS) is associated with reproductive, endocrine, and metabolic abnormalities. Because hyperandrogenism is the most consistent PCOS feature, we used wild-type (WT) and androgen receptor (AR) knockout (ARKO) mice, together with a mouse model of PCOS, to investigate the contribution of genomic AR-mediated actions in the development of PCOS traits. PCOS features were induced by prenatal exposure to dihydrotestosterone (250 μg) or oil vehicle (control) on days 16-18 of gestation in WT, heterozygote, and homozygote ARKO mice. DHT treatment of WT mice induced ovarian cysts (100% vs 0%), disrupted estrous cycles (42% vs 100% cycling), and led to fewer corpora lutea (5.0±0.4 vs 9.8±1.8). However, diestrus serum LH and FSH, and estradiol-induced-negative feedback as well as hypothalamic expression of kisspeptin, neurokinin B, and dynorphin, were unaffected by DHT treatment in WT mice. DHT-treated WT mice exhibited a more than 48% increase in adipocyte area but without changes in body fat. In contrast, heterozygous and homozygous ARKO mice exposed to DHT maintained comparable ovarian (histo)morphology, estrous cycling, and corpora lutea numbers, without any increase in adipocyte size. These findings provide strong evidence that genomic AR signaling is an important mediator in the development of these PCOS traits with a dose dependency that allows even AR haplosufficiency to prevent induction by prenatal androgenization of PCOS features in adult life.

Predictors of complications in gynaecological oncological surgery: a prospective multicentre study (UKGOSOC-UK gynaecological oncology surgical outcomes and complications)

BACKGROUND

There are limited data on surgical outcomes in gynaecological oncology. We report on predictors of complications in a multicentre prospective study.

METHODS

Data on surgical procedures and resulting complications were contemporaneously recorded on consented patients in 10 participating UK gynaecological cancer centres. Patients were sent follow-up letters to capture any further complications. Post-operative (Post-op) complications were graded (I-V) in increasing severity using the Clavien-Dindo system. Grade I complications were excluded from the analysis. Univariable and multivariable regression was used to identify predictors of complications using all surgery for intra-operative (Intra-op) and only those with both hospital and patient-reported data for Post-op complications.

RESULTS

Prospective data were available on 2948 major operations undertaken between April 2010 and February 2012. Median age was 62 years, with 35% obese and 20.4% ASA grade ⩾3. Consultant gynaecological oncologists performed 74.3% of operations. Intra-op complications were reported in 139 of 2948 and Grade II-V Post-op complications in 379 of 1462 surgeries. The predictors of risk were different for Intra-op and Post-op complications. For Intra-op complications, previous abdominal surgery, metabolic/endocrine disorders (excluding diabetes), surgical complexity and final diagnosis were significant in univariable and multivariable regression (P<0.05), with diabetes only in multivariable regression (P=0.006). For Post-op complications, age, comorbidity status, diabetes, surgical approach, duration of surgery, and final diagnosis were significant in both univariable and multivariable regression (P<0.05).

CONCLUSIONS

This multicentre prospective audit benchmarks the considerable morbidity associated with gynaecological oncology surgery. There are significant patient and surgical factors that influence this risk.